From patchwork Fri Mar 26 20:33:55 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Asmaa Mnebhi X-Patchwork-Id: 1459033 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (no SPF record) smtp.mailfrom=lists.ubuntu.com (client-ip=91.189.94.19; helo=huckleberry.canonical.com; envelope-from=kernel-team-bounces@lists.ubuntu.com; receiver=) Received: from huckleberry.canonical.com (huckleberry.canonical.com [91.189.94.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 4F6Yc25Sr6z9sRK; Sat, 27 Mar 2021 07:34:26 +1100 (AEDT) Received: from localhost ([127.0.0.1] helo=huckleberry.canonical.com) by huckleberry.canonical.com with esmtp (Exim 4.86_2) (envelope-from ) id 1lPt9x-0000dy-Rl; Fri, 26 Mar 2021 20:34:21 +0000 Received: from mail-il-dmz.mellanox.com ([193.47.165.129] helo=mellanox.co.il) by huckleberry.canonical.com with esmtp (Exim 4.86_2) (envelope-from ) id 1lPt9h-0000cX-8B for kernel-team@lists.ubuntu.com; Fri, 26 Mar 2021 20:34:05 +0000 Received: from Internal Mail-Server by MTLPINE1 (envelope-from asmaa@mellanox.com) with SMTP; 26 Mar 2021 23:34:02 +0300 Received: from farm-0002.mtbu.labs.mlnx (farm-0002.mtbu.labs.mlnx [10.15.2.32]) by mtbu-labmailer.labs.mlnx (8.14.4/8.14.4) with ESMTP id 12QKY2W7018962; Fri, 26 Mar 2021 16:34:02 -0400 Received: (from asmaa@localhost) by farm-0002.mtbu.labs.mlnx (8.14.7/8.13.8/Submit) id 12QKY2sQ031650; Fri, 26 Mar 2021 16:34:02 -0400 From: Asmaa Mnebhi To: kernel-team@lists.ubuntu.com Subject: [SRU][F:linux-bluefield][PATCH 0/1] UBUNTU: SAUCE: Syncup i2c-mlx driver with upstreamed version Date: Fri, 26 Mar 2021 16:33:55 -0400 Message-Id: <1616790835-31608-2-git-send-email-asmaa@nvidia.com> X-Mailer: git-send-email 2.1.2 In-Reply-To: <1616790835-31608-1-git-send-email-asmaa@nvidia.com> References: <1616790835-31608-1-git-send-email-asmaa@nvidia.com> X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.20 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: asmaa@nvidia.com MIME-Version: 1.0 Errors-To: kernel-team-bounces@lists.ubuntu.com Sender: "kernel-team" BugLink: https://bugs.launchpad.net/bugs/1921506 This patch syncs up the i2c-mlx driver with the upstreamed version. It also adds the multi slave functionality on top of it and fixes a bug related to inaccurate core frequency. Signed-off-by: Asmaa Mnebhi Reviewed-by: Khalil Blaiech Signed-off-by: Asmaa Mnebhi Acked-by: Stefan Bader Acked-by: Stefan Bader --- Documentation/devicetree/bindings/i2c/i2c-mlx.txt | 42 - .../bindings/i2c/mellanox,i2c-mlxbf.yaml | 78 + drivers/i2c/busses/Kconfig | 11 +- drivers/i2c/busses/Makefile | 2 +- drivers/i2c/busses/i2c-mlx.c | 2555 -------------------- drivers/i2c/busses/i2c-mlxbf.c | 2454 +++++++++++++++++++ 6 files changed, 2539 insertions(+), 2603 deletions(-) delete mode 100644 Documentation/devicetree/bindings/i2c/i2c-mlx.txt create mode 100644 Documentation/devicetree/bindings/i2c/mellanox,i2c-mlxbf.yaml delete mode 100644 drivers/i2c/busses/i2c-mlx.c create mode 100644 drivers/i2c/busses/i2c-mlxbf.c diff --git a/Documentation/devicetree/bindings/i2c/i2c-mlx.txt b/Documentation/devicetree/bindings/i2c/i2c-mlx.txt deleted file mode 100644 index 056a094..0000000 --- a/Documentation/devicetree/bindings/i2c/i2c-mlx.txt +++ /dev/null @@ -1,42 +0,0 @@ -Device tree configuration for the Mellanox I2C SMBus on BlueField SoCs - -Required Properties: - -- compatible : should be "mellanox,i2c-mlxbf1" or "mellanox,i2c-mlxbf2". - -- reg : address offset and length of the device registers. The - registers consist of the following set of resources: - 1) Smbus block registers. - 2) Cause master registers. - 3) Cause slave registers. - 4) Cause coalesce registers (if compatible isn't set - to "mellanox,i2c-mlxbf1"). - -- interrupts : interrupt number. - -Optional Properties: - -- clock-frequency : bus frequency used to configure timing registers; - allowed values are 100000, 400000 and 1000000; - those are expressed in Hz. Default is 100000. - -Example: - -i2c@2804000 { - compatible = "mellanox,i2c-mlxbf1"; - reg = <0x02804000 0x800>, - <0x02801200 0x020>, - <0x02801260 0x020>; - interrupts = <57>; - clock-frequency = <100000>; -}; - -i2c@2808800 { - compatible = "mellanox,i2c-mlxbf2"; - reg = <0x02808800 0x600>, - <0x02808e00 0x020>, - <0x02808e20 0x020>, - <0x02808e40 0x010>; - interrupts = <57>; - clock-frequency = <400000>; -}; diff --git a/Documentation/devicetree/bindings/i2c/mellanox,i2c-mlxbf.yaml b/Documentation/devicetree/bindings/i2c/mellanox,i2c-mlxbf.yaml new file mode 100644 index 0000000..d2b401d --- /dev/null +++ b/Documentation/devicetree/bindings/i2c/mellanox,i2c-mlxbf.yaml @@ -0,0 +1,78 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/i2c/mellanox,i2c-mlxbf.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Mellanox I2C SMBus on BlueField SoCs + +maintainers: + - Khalil Blaiech + +allOf: + - $ref: /schemas/i2c/i2c-controller.yaml# + +properties: + compatible: + enum: + - mellanox,i2c-mlxbf1 + - mellanox,i2c-mlxbf2 + + reg: + minItems: 3 + maxItems: 4 + items: + - description: Smbus block registers + - description: Cause master registers + - description: Cause slave registers + - description: Cause coalesce registers + + interrupts: + maxItems: 1 + + clock-frequency: + enum: [ 100000, 400000, 1000000 ] + description: + bus frequency used to configure timing registers; + The frequency is expressed in Hz. Default is 100000. + +required: + - compatible + - reg + - interrupts + +unevaluatedProperties: false + +if: + properties: + compatible: + contains: + enum: + - mellanox,i2c-mlxbf1 + +then: + properties: + reg: + maxItems: 3 + +examples: + - | + i2c@2804000 { + compatible = "mellanox,i2c-mlxbf1"; + reg = <0x02804000 0x800>, + <0x02801200 0x020>, + <0x02801260 0x020>; + interrupts = <57>; + clock-frequency = <100000>; + }; + + - | + i2c@2808800 { + compatible = "mellanox,i2c-mlxbf2"; + reg = <0x02808800 0x600>, + <0x02808e00 0x020>, + <0x02808e20 0x020>, + <0x02808e40 0x010>; + interrupts = <57>; + clock-frequency = <400000>; + }; diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig index 39fbe01..8e17de4 100644 --- a/drivers/i2c/busses/Kconfig +++ b/drivers/i2c/busses/Kconfig @@ -722,15 +722,16 @@ config I2C_LPC2K This driver can also be built as a module. If so, the module will be called i2c-lpc2k. -config I2C_MELLANOX +config I2C_MLXBF tristate "Mellanox BlueField I2C controller" - depends on (MELLANOX_PLATFORM && ARM64) || COMPILE_TEST + depends on MELLANOX_PLATFORM && ARM64 + select I2C_SLAVE help - Enabling this option will add specific I2C SMBus support for Mellanox - BlueField system. + Enabling this option will add I2C SMBus support for Mellanox BlueField + system. This driver can also be built as a module. If so, the module will be - called i2c-mlx. + called i2c-mlxbf. This driver implements an I2C SMBus host controller and enables both master and slave functions. diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile index 0595976..00277b4 100644 --- a/drivers/i2c/busses/Makefile +++ b/drivers/i2c/busses/Makefile @@ -74,7 +74,7 @@ obj-$(CONFIG_I2C_IOP3XX) += i2c-iop3xx.o obj-$(CONFIG_I2C_JZ4780) += i2c-jz4780.o obj-$(CONFIG_I2C_KEMPLD) += i2c-kempld.o obj-$(CONFIG_I2C_LPC2K) += i2c-lpc2k.o -obj-$(CONFIG_I2C_MELLANOX) += i2c-mlx.o +obj-$(CONFIG_I2C_MLXBF) += i2c-mlxbf.o obj-$(CONFIG_I2C_MESON) += i2c-meson.o obj-$(CONFIG_I2C_MPC) += i2c-mpc.o obj-$(CONFIG_I2C_MT65XX) += i2c-mt65xx.o diff --git a/drivers/i2c/busses/i2c-mlx.c b/drivers/i2c/busses/i2c-mlx.c deleted file mode 100644 index f5e8a1b..0000000 --- a/drivers/i2c/busses/i2c-mlx.c +++ /dev/null @@ -1,2555 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -/* - * Mellanox i2c bus driver - * - * Copyright (C) 2019 Mellanox Technologies, Ltd. - */ - -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include - -/* Defines what functionality is present */ -#define MLX_I2C_FUNC_SMBUS_BLOCK \ - (I2C_FUNC_SMBUS_BLOCK_DATA | I2C_FUNC_SMBUS_BLOCK_PROC_CALL) - -#define MLX_I2C_FUNC_SMBUS_DEFAULT \ - (I2C_FUNC_SMBUS_BYTE | I2C_FUNC_SMBUS_BYTE_DATA | \ - I2C_FUNC_SMBUS_WORD_DATA | I2C_FUNC_SMBUS_I2C_BLOCK | \ - I2C_FUNC_SMBUS_PROC_CALL) - -#define MLX_I2C_FUNC_ALL \ - (MLX_I2C_FUNC_SMBUS_DEFAULT | MLX_I2C_FUNC_SMBUS_BLOCK | \ - I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SLAVE) - -#define MLX_I2C_SMBUS_MAX 3 - -/* - * Shared resources info in BlueField platforms - */ - -#define I2C_COALESCE_TYU_ADDR 0x02801300 -#define I2C_COALESCE_TYU_SIZE 0x010 - -#define I2C_GPIO_TYU_ADDR 0x02802000 -#define I2C_GPIO_TYU_SIZE 0x100 - -#define I2C_COREPLL_TYU_ADDR 0x02800358 -#define I2C_COREPLL_TYU_SIZE 0x008 - -#define I2C_COREPLL_YU_ADDR 0x02800c30 -#define I2C_COREPLL_YU_SIZE 0x00c - -#define I2C_SHARED_RES_MAX 3 - -/* - * Note that the following SMBus, CAUSE, GPIO and PLL register addresses - * refer to their respective offsets relative to the corresponding - * memory-mapped region whose addresses are specified in either the DT or - * the ACPI tables or above. - */ - -/* - * Configuration for PLL: - */ - -/* - * SMBus Master core clock frequency. Timing configurations are - * strongly dependent on the core clock frequency of the SMBus - * Master. Default value is set to 400MHz. - */ -#define BLUEFIELD_TYU_PLL_OUT_FREQ (400 * 1000 * 1000) -/* Reference clock - 156 MHz */ -#define BLUEFIELD_PLL_IN_FREQ 156250000 - -/* PLL registers */ -#define I2C_CORE_PLL_REG0 0x0 -#define I2C_CORE_PLL_REG1 0x4 -#define I2C_CORE_PLL_REG2 0x8 - -/* - * Configuration for cause: - */ - -/* OR cause register */ -#define I2C_CAUSE_OR_EVTEN2_BITS 0x0c -#define I2C_CAUSE_OR_EVTEN1_BITS 0x10 -#define I2C_CAUSE_OR_EVTEN0_BITS 0x14 -#define I2C_CAUSE_OR_CLEAR_BITS 0x18 - -/* Arbiter Cause Register */ -#define I2C_CAUSE_ARBITER_BITS 0x1c - -/* - * Cause Status flags. Note that those bits might be considered - * as interrupt enabled bits. - */ -#define CAUSE_TRANSACTION_ENDED 0x001 /* Transaction ended with STOP */ -#define CAUSE_M_ARBITRATION_LOST 0x002 /* Master arbitration lost */ -#define CAUSE_UNEXPECTED_START 0x004 /* Unexpected start detected */ -#define CAUSE_UNEXPECTED_STOP 0x008 /* Unexpected stop detected */ -#define CAUSE_WAIT_FOR_FW_DATA 0x010 /* Wait for transfer continuation */ -#define CAUSE_PUT_STOP_FAILED 0x020 /* Failed to generate STOP */ -#define CAUSE_PUT_START_FAILED 0x040 /* Failed to generate START */ -#define CAUSE_CLK_TOGGLE_DONE 0x080 /* Clock toggle completed */ -#define CAUSE_M_FW_TIMEOUT 0x100 /* Transfer timeout occurred */ -#define CAUSE_M_GW_BUSY_FALL 0x200 /* Master busy bit reset */ - -#define CAUSE_MASTER_ARBITER_BITS_MASK 0x000003ff /* 10 bits */ - -/* - * Slave cause status flags. Note that those bits might be considered - * as interrupt enabled bits. - */ - -/* Write transaction received successfully */ -#define CAUSE_WRITE_SUCCESS 0x000001 -/* Write transaction terminated due to unexpected token */ -#define CAUSE_WRITE_UNEXPECTED_TOK 0x000002 -/* External master is trying to write more than 128 Bytes */ -#define CAUSE_WRITE_TOO_LONG 0x000004 -/* Read transaction ended successfully with NACK */ -#define CAUSE_READ_SUCCESS_NACK 0x000008 -/* Read transaction ended unexpected with NACK */ -#define CAUSE_READ_UNEXPECTED_NACK 0x000010 -/* Transaction failed due to arbitration lost */ -#define CAUSE_S_ARBITRATION_LOST 0x000080 -/* Read transaction terminated due to unexpected start */ -#define CAUSE_READ_UNEXPECTED_START 0x000100 -/* Read transaction terminated due to unexpected stop */ -#define CAUSE_READ_UNEXPECTED_STOP 0x000200 -/* Read transaction aborted due to stretch timeout */ -#define CAUSE_READ_TIMEOUT 0x000400 -/* Waiting for ACK/NACK */ -#define CAUSE_WAIT_FOR_ACK_NACK 0x001000 -/* Read transaction received, waiting for response */ -#define CAUSE_READ_WAIT_FW_RESPONSE 0x002000 -/* Write transaction aborted due to stretch timeout */ -#define CAUSE_WRITE_TIMEOUT 0x004000 -/* Incorrect slave address at the beginning of read phase */ -#define CAUSE_BAD_SLAVE_ADDRESS 0x008000 -/* SCL is idle while SDA is driven by slave */ -#define CAUSE_SCL_IDLE_SLAVE_SDA 0x010000 -/* Timeout while waiting for response */ -#define CAUSE_S_FW_TIMEOUT 0x020000 -/* Slave busy bit reset */ -#define CAUSE_S_GW_BUSY_FALL 0x040000 -/* Master acked last written byte, need to supply more bytes */ -#define CAUSE_MASTER_EXPECTING_DATA 0x080000 -/* Master nacked byte but didn't generate stop */ -#define CAUSE_NO_STOP_AFTER_NACK 0x100000 - -#define CAUSE_SLAVE_ARBITER_BITS_MASK 0x001fffff /* 21 bits */ - -/* Cause Coalesce registers */ -#define I2C_CAUSE_COALESCE_0 0x00 -#define I2C_CAUSE_COALESCE_1 0x04 -#define I2C_CAUSE_COALESCE_2 0x08 - -#define I2C_CAUSE_TYU_SLAVE_BIT MLX_I2C_SMBUS_MAX -#define I2C_CAUSE_YU_SLAVE_BIT 1 - -/* - * Configuration for GPIO: - */ -/* Functional enable register */ -#define I2C_GPIO_0_FUNC_EN_0 0x28 -/* Force OE enable register */ -#define I2C_GPIO_0_FORCE_OE_EN 0x30 -/* - * Note that Smbus GWs are on GPIOs 30:25. Two pins are used to control - * SDA/SCL lines: - * - * SMBUS GW0 -> bits[26:25] - * SMBUS GW1 -> bits[28:27] - * SMBUS GW2 -> bits[30:29] - */ -#define I2C_GPIO_SMBUS_GW_PINS(num) (25 + ((num) << 1)) - -/* gw_id can be 0,1 or 2 */ -#define I2C_GPIO_SMBUS_GW_MASK(num) \ - (0xffffffff & (~(0x3 << I2C_GPIO_SMBUS_GW_PINS(num)))) - -#define I2C_GPIO_SMBUS_GW_RESET_PINS(num, val) \ - ((val) & I2C_GPIO_SMBUS_GW_MASK((num))) - -#define I2C_GPIO_SMBUS_GW_ASSERT_PINS(num, val) \ - ((val) | (0x3 << I2C_GPIO_SMBUS_GW_PINS((num)))) - -/* - * SMBus Timing Parameters: - */ -#define SMBUS_TIMER_SCL_LOW_SCL_HIGH 0x00 -#define SMBUS_TIMER_FALL_RISE_SPIKE 0x04 -#define SMBUS_TIMER_THOLD 0x08 -#define SMBUS_TIMER_TSETUP_START_STOP 0x0c -#define SMBUS_TIMER_TSETUP_DATA 0x10 -#define SMBUS_THIGH_MAX_TBUF 0x14 -#define SMBUS_SCL_LOW_TIMEOUT 0x18 - -/* - * Defines SMBus operating frequency and core clock frequency. - * According to ADB files, default values are compliant to 100KHz SMBus - * @ 400MHz core clock. The driver should be able to calculate core - * frequency based on PLL parameters. - */ -#define MLX_I2C_COREPLL_FREQ BLUEFIELD_TYU_PLL_OUT_FREQ - -#define MLX_I2C_TIMING_CONFIG_HZ 100000 - -/* Core PLL frequency */ -static u64 corepll_frequency; - -/* SMBus SCL clock high period setup */ -enum { - SMBUS_SCL_HIGH_100KHZ = 4810, - SMBUS_SCL_HIGH_400KHZ = 1011, - SMBUS_SCL_HIGH_1000KHZ = 600 -}; - -/* - * SMBus Master GW Registers: - */ - -/* SMBus Master GW */ -#define SMBUS_MASTER_GW 0x200 -/* Number of bytes received and sent */ -#define SMBUS_RS_BYTES 0x300 -/* Packet error check (PEC) value */ -#define SMBUS_MASTER_PEC 0x304 -/* Status bits (ACK/NACK/FW Timeout) */ -#define SMBUS_MASTER_STATUS 0x308 -/* Shift left GW data bytes */ -#define SMBUS_READ_SHIFT 0x30c -/* SMbus Master Finite State Machine */ -#define SMBUS_MASTER_FSM 0x310 -/* Toggle Clock */ -#define SMBUS_MASTER_CLK 0x314 -/* SDA and SCL configuration */ -#define SMBUS_MASTER_CFG 0x318 -/* - * When enabled, the master will issue a stop condition in case of - * timeout while waiting for FW response. - */ -#define SMBUS_EN_FW_TIMEOUT 0x31c - -/* SMBus Master GW control bits offset in SMBUS_MASTER_GW[31:3] */ -#define MASTER_LOCK_BIT_OFF 31 /* Lock bit */ -#define MASTER_BUSY_BIT_OFF 30 /* Busy bit */ -#define MASTER_START_BIT_OFF 29 /* Control start */ -#define MASTER_CTL_WRITE_BIT_OFF 28 /* Control write phase */ -#define MASTER_WRITE_BIT_OFF 21 /* Control write bytes */ -#define MASTER_SEND_PEC_BIT_OFF 20 /* Send PEC byte when set to 1 */ -#define MASTER_CTL_READ_BIT_OFF 19 /* Control read phase */ -#define MASTER_PARSE_EXP_BIT_OFF 11 /* Control parse expected bytes */ -#define MASTER_SLV_ADDR_BIT_OFF 12 /* Slave address */ -#define MASTER_READ_BIT_OFF 4 /* Control read bytes */ -#define MASTER_STOP_BIT_OFF 3 /* Control stop */ - -/* SMBus Master GW Data descriptor */ -#define MASTER_DATA_DESC_ADDR 0x280 /* Address */ -#define MASTER_DATA_DESC_SIZE 0x80 /* Data descriptor size in bytes */ -#define MASTER_CTL_DATA_MAX_SIZE 4 /* Control data size in bytes */ -#define MASTER_DATA_W_OFF \ - (MASTER_DATA_DESC_ADDR + MASTER_CTL_DATA_MAX_SIZE) - -/* Maximum bytes to read/write per SMBus transaction */ -#define MASTER_DATA_R_LENGTH MASTER_DATA_DESC_SIZE -#define MASTER_DATA_W_LENGTH (MASTER_DATA_DESC_SIZE - 1) - -/* SMBus Master GW Status flags */ -#define SMBUS_STATUS_BYTE_CNT_DONE 0x1 /* All bytes were transmitted */ -#define SMBUS_STATUS_NACK_RCV 0x2 /* NACK received */ -#define SMBUS_STATUS_READ_ERR 0x4 /* Slave's byte count > 128 bytes */ -#define SMBUS_STATUS_FW_TIMEOUT 0x8 /* Timeout occurred */ - -#define SMBUS_MASTER_STATUS_MASK 0x0000000f /* 4 bits */ - -#define SMBUS_MASTER_FSM_STOP_MASK 0x80000000 -#define SMBUS_MASTER_FSM_PS_STATE_MASK 0x00008000 - -/* - * SMBus Slave Parameters: - */ - -/* SMBus slave GW */ -#define SMBUS_SLAVE_GW 0x400 -/* Number of bytes received and sent from/to master */ -#define SMBUS_SLAVE_RS_MASTER_BYTES 0x500 -/* Packet error check (PEC) value */ -#define SMBUS_SLAVE_PEC 0x504 -/* Shift left GW data bytes */ -#define SMBUS_SLAVE_READ_SHIFT 0x508 -/* SMbus Slave Finite State Machine (FSM) */ -#define SMBUS_SLAVE_FSM 0x510 -/* SMBus CR Master configuration register */ -#define SMBUS_SLAVE_CRMASTER_CFG 0x524 -/* - * When enabled, FSM will return to idle in case of stretch timeout - * while waiting for FW response. - */ -#define SMBUS_SLAVE_EN_FW_TIMEOUT 0x528 -/* - * Should be set when all raised causes handled, and cleared by HW on - * every new cause. - */ -#define SMBUS_SLAVE_READY 0x52c -/* SMBus Device Default Address as defined in SMBus spec */ -#define SMBUS_SLAVE_ARP_ADDR 0x530 -/* If set, then the Slave is in middle of ARP transaction */ -#define SMBUS_SLAVE_ARP_STATUS 0x534 -/* Slave cause register */ -#define SMBUS_SLAVE_CAUSE 0x53c -/* SMBus CR Master FSM */ -#define SMBUS_SLAVE_CRMASTER_FSM 0x540 -/* Slave SDA and SCL output */ -#define SMBUS_SLAVE_CLK_OUTPUT 0x544 - -/* SMBus Slave GW control bits offset in SMBUS_SLAVE_GW[31:19] */ -#define SLAVE_LOCK_BIT_OFF 31 /* Lock bit */ -#define SLAVE_BUSY_BIT_OFF 30 /* Busy bit */ -#define SLAVE_WRITE_BIT_OFF 29 /* Control write enable */ -#define SLAVE_WRITE_BYTES_BIT_OFF 22 /* Number of bytes to write */ -#define SLAVE_SEND_PEC_BIT_OFF 21 /* Send PEC byte when set to 1 */ -#define SLAVE_NACK_BIT_OFF 20 /* Nack bit */ -#define SLAVE_CONT_WRITE_BIT_OFF 19 /* Continue write transaction */ - -/* SMBus Slave GW Data descriptor */ -#define SLAVE_DATA_DESC_ADDR 0x480 /* Address */ -#define SLAVE_DATA_DESC_SIZE 0x80 /* Data descriptor size in bytes */ -#define SLAVE_DATA_DESC_SKIP 1 /* Bytes to skip within data descriptor */ - -/* SMbus Slave configuration registers */ -#define SMBUS_SLAVE_ADDR_CFG 0x514 -#define SMBUS_SLAVE_ADDR_CNT 16 -#define SMBUS_SLAVE_ADDR_EN_BIT 7 -#define SMBUS_SLAVE_ADDR_MASK 0x7f - -/* - * Timeout is given in microsends. Note also that timeout handling is not - * exact. - */ -#define SMBUS_TIMEOUT (300 * 1000) /* 300ms */ - -/* Encapsulates timing parameters */ -struct mlx_i2c_timings { - u16 scl_high; /* Clock high period */ - u16 scl_low; /* Clock low period */ - u8 sda_rise; /* Data Rise Time */ - u8 sda_fall; /* Data Fall Time */ - u8 scl_rise; /* Clock Rise Time */ - u8 scl_fall; /* Clock Fall Time */ - u16 hold_start; /* Hold time after (REPEATED) START */ - u16 hold_data; /* Data hold time */ - u16 setup_start; /* REPEATED START Condition setup time */ - u16 setup_stop; /* STOP Condition setup time */ - u16 setup_data; /* Data setup time */ - u16 pad; /* Padding */ - u16 buf; /* Bus free time between STOP and START */ - u16 thigh_max; /* Thigh max */ - u32 timeout; /* Detect clock low timeout */ -}; - -enum { - I2C_F_READ = 0x01, - I2C_F_WRITE = 0x02, - I2C_F_NORESTART = 0x08, - I2C_F_SMBUS_OPERATION = 0x10, - I2C_F_SMBUS_BLOCK = 0x20, - I2C_F_SMBUS_PEC = 0x40, - I2C_F_SMBUS_PROCESS_CALL = 0x80 -}; - -struct mlx_smbus_operation { - u32 flags; - u32 length; /* buffer length in bytes */ - u8 *buffer; -}; - -#define I2C_SMBUS_OPERATION_CNT 3 - -struct mlx_smbus_request { - u8 slave; - u8 operation_cnt; - struct mlx_smbus_operation operation[I2C_SMBUS_OPERATION_CNT]; -}; - -struct mlx_i2c_resource { - void __iomem *io; - struct resource *params; - struct mutex *lock; - u8 type; -}; - -/* List of chip resources that are being accessed by the driver. */ -enum { - I2C_SMBUS_RES, - I2C_MST_CAUSE_RES, - I2C_SLV_CAUSE_RES, - I2C_COALESCE_RES, - I2C_COREPLL_RES, - I2C_GPIO_RES, - I2C_END_RES -}; - -/* - * Helper macro to define an I2C resource parameters. - */ -#define MLX_I2C_RES_PARAMS(addr, size, str) \ - { \ - .start = (addr), \ - .end = (addr) + (size) - 1, \ - .name = (str) \ - } - -static struct resource coalesce_tyu_params = MLX_I2C_RES_PARAMS( - I2C_COALESCE_TYU_ADDR, I2C_COALESCE_TYU_SIZE, "COALESCE_MEM"); -static struct resource corepll_tyu_params = MLX_I2C_RES_PARAMS( - I2C_COREPLL_TYU_ADDR, I2C_COREPLL_TYU_SIZE, "COREPLL_MEM"); -static struct resource corepll_yu_params = MLX_I2C_RES_PARAMS( - I2C_COREPLL_YU_ADDR, I2C_COREPLL_YU_SIZE, "COREPLL_MEM"); -static struct resource gpio_tyu_params = MLX_I2C_RES_PARAMS( - I2C_GPIO_TYU_ADDR, I2C_GPIO_TYU_SIZE, "GPIO_MEM"); - -static DEFINE_MUTEX(coalesce_lock); -static DEFINE_MUTEX(corepll_lock); -static DEFINE_MUTEX(gpio_lock); - -/* Mellanox BlueField chip type. */ -enum mlx_chip_type { - MLX_BLUEFIELD1_CHIP, - MLX_BLUEFIELD2_CHIP -}; - -struct mlx_chip_info { - enum mlx_chip_type type; - /* Chip shared resources that are being used by the I2C controller. */ - struct mlx_i2c_resource *shared_res[I2C_SHARED_RES_MAX]; - - /* Callback to calculate the core PLL frequency. */ - u64 (*calculate_freq)(struct mlx_i2c_resource *corepll_res); -}; - -struct mlx_i2c_priv { - struct mlx_chip_info *chip; - struct i2c_adapter adap; - struct mlx_i2c_resource *smbus; - struct mlx_i2c_resource *mst_cause; - struct mlx_i2c_resource *slv_cause; - struct mlx_i2c_resource *coalesce; - u64 frequency; /* Core frequency in Hz */ - int bus; /* physical bus identifier */ - struct i2c_client *slave[SMBUS_SLAVE_ADDR_CNT]; -}; - -static struct mlx_i2c_resource g_coalesce_res[] = { - [MLX_BLUEFIELD1_CHIP] = { - .params = &coalesce_tyu_params, - .lock = &coalesce_lock, - .type = I2C_COALESCE_RES - }, - {} -}; - -static struct mlx_i2c_resource g_corepll_res[] = { - [MLX_BLUEFIELD1_CHIP] = { - .params = &corepll_tyu_params, - .lock = &corepll_lock, - .type = I2C_COREPLL_RES - }, - [MLX_BLUEFIELD2_CHIP] = { - .params = &corepll_yu_params, - .lock = &corepll_lock, - .type = I2C_COREPLL_RES, - } -}; - -static struct mlx_i2c_resource g_gpio_res[] = { - [MLX_BLUEFIELD1_CHIP] = { - .params = &gpio_tyu_params, - .lock = &gpio_lock, - .type = I2C_GPIO_RES - }, - {} -}; - -static u8 i2c_bus_count; - -static DEFINE_MUTEX(i2c_bus_lock); - -/* Polling frequency in microseconds */ -#define POLL_FREQ_IN_USEC 200 - -static void smbus_write(void __iomem *io, int reg, u32 val) -{ - writel(val, io + reg); -} - -static u32 smbus_read(void __iomem *io, int reg) -{ - return readl(io + reg); -} - -/* - * This function is used to read data from Master GW Data Descriptor. - * Data bytes in the Master GW Data Descriptor are shifted left so the - * data starts at the MSB of the descriptor registers as set by the - * underlying hardware. TYU_READ_DATA enables byte swapping while - * reading data bytes, and MUST be called by the SMBus read routines - * to copy data from the 32 * 32-bit HW Data registers a.k.a Master GW - * Data Descriptor. - */ -static u32 smbus_read_data(void __iomem *io, int reg) -{ - return be32_to_cpu(smbus_read(io, reg)); -} - -/* - * This function is used to write data to the Master GW Data Descriptor. - * Data copied to the Master GW Data Descriptor MUST be shifted left so - * the data starts at the MSB of the descriptor registers as required by - * the underlying hardware. TYU_WRITE_DATA enables byte swapping when - * writing data bytes, and MUST be called by the SMBus write routines to - * copy data to the 32 * 32-bit HW Data registers a.k.a Master GW Data - * Descriptor. - */ -static void smbus_write_data(void __iomem *io, int reg, u32 val) -{ - smbus_write(io, reg, cpu_to_be32(val)); -} - -/* - * I2C SMBus operations - */ - -/* - * Function to poll a set of bits at a specific address; it checks whether - * the bits are equal to zero when eq_zero is set to 'true', and not equal - * to zero when eq_zero is set to 'false'. - * Note that the timeout is given in microseconds. - */ -static u32 mlx_smbus_poll(void __iomem *io, u32 addr, u32 mask, - bool eq_zero, u32 timeout) -{ - u32 bits; - - timeout = (timeout / POLL_FREQ_IN_USEC) + 1; - - do { - bits = smbus_read(io, addr) & mask; - if (eq_zero ? bits == 0 : bits != 0) - return eq_zero ? 1 : bits; - udelay(POLL_FREQ_IN_USEC); - } while (timeout-- != 0); - - return 0; -} - -/* - * SW must make sure that the SMBus Master GW is idle before starting - * a transaction. Accordingly, this function polls the Master FSM stop - * bit; it returns false when the bit is asserted, true if not. - */ -static bool mlx_smbus_master_wait_for_idle(struct mlx_i2c_priv *priv) -{ - u32 addr = SMBUS_MASTER_FSM; - u32 mask = SMBUS_MASTER_FSM_STOP_MASK; - u32 timeout = SMBUS_TIMEOUT; - - if (mlx_smbus_poll(priv->smbus->io, addr, mask, true, timeout)) - return true; - - return false; -} - -/* - * Poll SMBus master status and return transaction status, - * i.e. whether succeeded or failed. I2C and SMBus fault codes - * are returned as negative numbers from most calls, with zero - * or some positive number indicating a non-fault return. - */ -static int mlx_i2c_smbus_check_status(struct mlx_i2c_priv *priv) -{ - u32 cause_status_bits; - u32 master_status_bits; - - /* - * GW busy bit is raised by the driver and cleared by the HW - * when the transaction is completed. The busy bit is a good - * indicator of transaction status. So poll the busy bit, and - * then read the cause and master status bits to determine if - * errors occurred during the transaction. - */ - mlx_smbus_poll(priv->smbus->io, SMBUS_MASTER_GW, - 1 << MASTER_BUSY_BIT_OFF, true, - SMBUS_TIMEOUT); - - /* Read cause status bits */ - cause_status_bits = - smbus_read(priv->mst_cause->io, I2C_CAUSE_ARBITER_BITS) & - CAUSE_MASTER_ARBITER_BITS_MASK; - - /* - * Parse both Cause and Master GW bits, then return transaction status. - */ - - master_status_bits = smbus_read(priv->smbus->io, SMBUS_MASTER_STATUS); - master_status_bits &= SMBUS_MASTER_STATUS_MASK; - - /* - * When transaction ended with STOP, all bytes were transmitted, - * and no NACK received, then the transaction ended successfully. - * On the other hand, when the GW is configured with the stop bit - * de-asserted then the SMBus expects the following GW configuration - * for transfer continuation. - */ - if ((cause_status_bits & CAUSE_WAIT_FOR_FW_DATA) || - ((cause_status_bits & CAUSE_TRANSACTION_ENDED) && - (master_status_bits & SMBUS_STATUS_BYTE_CNT_DONE) && - !(master_status_bits & SMBUS_STATUS_NACK_RCV))) - return 0; - - /* - * In case of timeout on GW busy, the ISR will clear busy bit but - * transaction ended bits cause will not be set so the transaction - * fails. Then, we must check Master GW status bits. - */ - if ((master_status_bits & (SMBUS_STATUS_NACK_RCV | - SMBUS_STATUS_READ_ERR | - SMBUS_STATUS_FW_TIMEOUT)) && - (cause_status_bits & (CAUSE_TRANSACTION_ENDED | - CAUSE_M_GW_BUSY_FALL))) - return -EIO; - - if (cause_status_bits & (CAUSE_M_ARBITRATION_LOST | - CAUSE_UNEXPECTED_START | - CAUSE_UNEXPECTED_STOP | - CAUSE_PUT_STOP_FAILED | - CAUSE_PUT_START_FAILED | - CAUSE_CLK_TOGGLE_DONE | - CAUSE_M_FW_TIMEOUT)) - return -EAGAIN; - - return -ETIMEDOUT; -} - -static void mlx_smbus_write_data(struct mlx_i2c_priv *priv, - const u8 *data, u8 length, u32 addr) -{ - u32 data32; - u8 offset; - - /* Copy data bytes from 4-byte aligned source buffer */ - for (offset = 0; offset < round_up(length, 4); offset += 4) { - data32 = *((u32 *)(data + offset)); - smbus_write_data(priv->smbus->io, addr + offset, data32); - } -} - -static void mlx_smbus_read_data(struct mlx_i2c_priv *priv, - u8 *data, u8 length, u32 addr) -{ - u32 data32; - u8 byte, offset; - - for (offset = 0; offset < (length & ~0x3); offset += 4) { - data32 = smbus_read_data(priv->smbus->io, addr + offset); - *((u32 *)(data + offset)) = data32; - } - - if (!(length & 0x3)) - return; - - data32 = smbus_read_data(priv->smbus->io, addr + offset); - - for (byte = 0; byte < (length & 0x3); byte++) { - data[offset + byte] = data32 & 0xff; - data32 >>= 8; - } -} - -static int mlx_smbus_enable(struct mlx_i2c_priv *priv, u8 slave, - u8 len, u8 block_en, u8 pec_en, bool read) -{ - u32 command; - - /* Set Master GW control word */ - command = 0; - command |= 0x1 << MASTER_LOCK_BIT_OFF; - command |= 0x1 << MASTER_BUSY_BIT_OFF; - command |= slave << MASTER_SLV_ADDR_BIT_OFF; - command |= 0x1 << MASTER_START_BIT_OFF; - command |= 0x1 << MASTER_STOP_BIT_OFF; - if (read) { - command |= len << MASTER_READ_BIT_OFF; - command |= 1 << MASTER_CTL_READ_BIT_OFF; - } else { - command |= len << MASTER_WRITE_BIT_OFF; - command |= 1 << MASTER_CTL_WRITE_BIT_OFF; - } - command |= block_en << MASTER_PARSE_EXP_BIT_OFF; - command |= pec_en << MASTER_SEND_PEC_BIT_OFF; - - /* Clear status bits */ - smbus_write(priv->smbus->io, SMBUS_MASTER_STATUS, 0x0); - /* Set the cause data */ - smbus_write(priv->smbus->io, I2C_CAUSE_OR_CLEAR_BITS, ~0x0); - /* Zero PEC byte */ - smbus_write(priv->smbus->io, SMBUS_MASTER_PEC, 0x0); - /* Zero byte count */ - smbus_write(priv->smbus->io, SMBUS_RS_BYTES, 0x0); - - /* GW activation */ - smbus_write(priv->smbus->io, SMBUS_MASTER_GW, command); - - /* - * Poll master status and check status bits. An ACK is sent when - * completing writing data to the bus (Master 'byte_count_done' bit - * is set to 1). - */ - return mlx_i2c_smbus_check_status(priv); -} - -static int mlx_smbus_start_transaction(struct mlx_i2c_priv *priv, - struct mlx_smbus_request *request) -{ - struct mlx_smbus_operation *operation; - u8 data_desc[MASTER_DATA_DESC_SIZE] = { 0 }; - u8 op_idx, data_idx, data_len, write_len, read_len; - u8 read_en, write_en, block_en, pec_en; - u8 slave, flags, addr; - u8 *read_buf; - int ret = 0; - - if (request->operation_cnt > I2C_SMBUS_OPERATION_CNT) - return -EINVAL; - - read_buf = NULL; - data_idx = 0; - read_en = write_en = 0; - write_len = read_len = 0; - block_en = 0; - pec_en = 0; - slave = request->slave & 0x7f; - addr = slave << 1; - - /* First of all, check whether the HW is idle */ - if (WARN_ON(!mlx_smbus_master_wait_for_idle(priv))) - return -EBUSY; - - /* Set first byte */ - data_desc[data_idx++] = addr; - - for (op_idx = 0; op_idx < request->operation_cnt; op_idx++) { - operation = &request->operation[op_idx]; - flags = operation->flags; - - /* - * Note that read and write operations might be handled by a - * single command. If the I2C_F_SMBUS_OPERATION is set then - * write command byte and set the optional SMBus specific bits - * such as block_en and pec_en. These bits MUST be submitted by - * the first operation only. - */ - if (op_idx == 0 && flags & I2C_F_SMBUS_OPERATION) { - block_en = flags & I2C_F_SMBUS_BLOCK; - pec_en = flags & I2C_F_SMBUS_PEC; - } - - if (flags & I2C_F_WRITE) { - write_en = 1; - write_len += operation->length; - memcpy(data_desc + data_idx, - operation->buffer, operation->length); - data_idx += operation->length; - } - /* - * We assume that read operations are performed only once per - * SMBus transaction. *TBD* protect this statement so it won't - * be executed twice? or return an error if we try to read more - * than once? - */ - if (flags & I2C_F_READ) { - read_en = 1; - /* Subtract 1 as required by HW */ - read_len = operation->length - 1; - read_buf = operation->buffer; - } - } - - /* Set Master GW data descriptor */ - data_len = write_len + 1; /* add one byte of the slave address */ - /* - * Note that data_len cannot be 0. Indeed, the slave address byte - * must be written to the data registers. - */ - mlx_smbus_write_data(priv, (const u8 *)data_desc, data_len, - MASTER_DATA_DESC_ADDR); - - if (write_en) { - ret = mlx_smbus_enable(priv, slave, write_len, block_en, - pec_en, 0); - if (ret != 0) - return ret; - } - - if (read_en) { - /* Write slave address to Master GW data descriptor */ - mlx_smbus_write_data(priv, (const u8 *)&addr, 1, - MASTER_DATA_DESC_ADDR); - ret = mlx_smbus_enable(priv, slave, read_len, block_en, - pec_en, 1); - if (ret == 0) { - /* Get Master GW data descriptor */ - mlx_smbus_read_data(priv, data_desc, read_len + 1, - MASTER_DATA_DESC_ADDR); - - /* Get data from Master GW data descriptor */ - memcpy(read_buf, data_desc, read_len + 1); - } - - /* - * After a read operation the SMBus FSM ps (present state) - * needs to be 'manually' reset. This should be removed in - * next tag integration. - */ - smbus_write(priv->smbus->io, SMBUS_MASTER_FSM, - SMBUS_MASTER_FSM_PS_STATE_MASK); - } - - return ret; -} - -/* - * I2C SMBus protocols - */ - -static void mlx_smbus_quick_command(struct mlx_smbus_request *request, - u8 read) -{ - /* - * QuickWrite: OperationCount=1, - * LengthInBytes=0, Flags=I2C_F_WRITE - * - * QuickRead: OperationCount=1, - * LengthInBytes=0, Flags=I2C_F_WRITE - * | I2C_F_READ - */ - request->operation_cnt = 1; - - request->operation[0].length = 0; - request->operation[0].flags = I2C_F_WRITE; - request->operation[0].flags |= (read) ? I2C_F_READ : 0; -} - -static void mlx_smbus_byte_func(struct mlx_smbus_request *request, - u8 *data, bool read, bool pec_check) -{ - /* - * ReceiveByte: OperationCount=1, - * LengthInBytes=1, Flags=I2C_F_SMBUS_OPERATION - * | I2C_F_READ - * ReceiveByte+PEC: OperationCount=1, - * LengthInBytes=2, Flags=I2C_F_SMBUS_OPERATION - * | I2C_F_READ - * | I2C_F_SMBUS_PEC - * - * - * SendByte: OperationCount=1, - * LengthInBytes=1, Flags=I2C_F_SMBUS_OPERATION - * | I2C_F_WRITE - * SendByte+PEC: OperationCount=1, - * LengthInBytes=2, Flags=I2C_F_SMBUS_OPERATION - * | I2C_F_WRITE - * | I2C_F_SMBUS_PEC - */ - - request->operation_cnt = 1; - - request->operation[0].length = 1; - request->operation[0].length += (pec_check); - - request->operation[0].flags = I2C_F_SMBUS_OPERATION; - request->operation[0].flags |= (read) ? I2C_F_READ : I2C_F_WRITE; - request->operation[0].flags |= (pec_check) ? I2C_F_SMBUS_PEC : 0; - - request->operation[0].buffer = data; -} - -static void mlx_smbus_data_byte_func(struct mlx_smbus_request *request, - u8 *command, - u8 *data, bool read, bool pec_check) -{ - /* - * ReadDataByte: OperationCount=2, - * LengthInBytes=1, Flags=I2C_F_SMBUS_OPERATION - * | I2C_F_WRITE - * LengthInBytes=1, Flags=I2C_F_READ - * ReadDataByte+PEC: OperationCount=2, - * LengthInBytes=1, Flags=I2C_F_SMBUS_OPERATION - * | I2C_F_WRITE - * | I2C_F_SMBUS_PEC - * LengthInBytes=2, Flags=I2C_F_READ - * - * - * WriteDataByte: OperationCount=2, - * LengthInBytes=1, Flags=I2C_F_SMBUS_OPERATION - * | I2C_F_WRITE - * LengthInBytes=1, Flags=I2C_F_WRITE - * WriteDataByte+PEC: OperationCount=2, - * LengthInBytes=1, Flags=I2C_F_SMBUS_OPERATION - * | I2C_F_WRITE - * | I2C_F_SMBUS_PEC - * LengthInBytes=2, Flags=I2C_F_WRITE - */ - - request->operation_cnt = 2; - - request->operation[0].length = 1; - request->operation[0].flags = I2C_F_SMBUS_OPERATION | I2C_F_WRITE; - request->operation[0].flags |= (pec_check) ? I2C_F_SMBUS_PEC : 0; - request->operation[0].buffer = command; - - request->operation[1].length = 1; - request->operation[1].length += (pec_check); - request->operation[1].flags = (read) ? I2C_F_READ : I2C_F_WRITE; - request->operation[1].buffer = data; -} - -static void mlx_smbus_data_word_func(struct mlx_smbus_request *request, - u8 *command, - u8 *data, bool read, bool pec_check) -{ - /* - * ReadDataWord: OperationCount=2, - * LengthInBytes=1, Flags=I2C_F_SMBUS_OPERATION - * | I2C_F_WRITE - * LengthInBytes=2, Flags=I2C_F_READ - * ReadDataWord+PEC: OperationCount=2, - * LengthInBytes=1, Flags=I2C_F_SMBUS_OPERATION - * | I2C_F_WRITE - * | I2C_F_SMBUS_PEC - * LengthInBytes=3, Flags=I2C_F_READ - * - * - * WriteDataWord: OperationCount=2, - * LengthInBytes=1, Flags=I2C_F_SMBUS_OPERATION - * | I2C_F_WRITE - * LengthInBytes=2, Flags=I2C_F_WRITE - * WriteDataWord+PEC: OperationCount=2, - * LengthInBytes=1, Flags=I2C_F_SMBUS_OPERATION - * | I2C_F_WRITE - * | I2C_F_SMBUS_PEC - * LengthInBytes=3, Flags=I2C_F_WRITE - */ - - request->operation_cnt = 2; - - request->operation[0].length = 1; - request->operation[0].flags = I2C_F_SMBUS_OPERATION | I2C_F_WRITE; - request->operation[0].flags |= (pec_check) ? I2C_F_SMBUS_PEC : 0; - request->operation[0].buffer = command; - - request->operation[1].length = 2; - request->operation[1].length += (pec_check); - request->operation[1].flags = (read) ? I2C_F_READ : I2C_F_WRITE; - request->operation[1].buffer = data; -} - -static void mlx_smbus_i2c_block_func(struct mlx_smbus_request *request, - u8 *command, - u8 *data, - u8 *data_len, bool read, bool pec_check) -{ - /* - * ReadBlock: OperationCount=2, - * LengthInBytes=1, Flags=I2C_F_SMBUS_OPERATION - * | I2C_F_WRITE - * LengthInBytes=N, Flags=I2C_F_READ - * ReadBlock+PEC: OperationCount=2, - * LengthInBytes=1, Flags=I2C_F_SMBUS_OPERATION - * | I2C_F_WRITE - * | I2C_F_SMBUS_PEC - * LengthInBytes=N+1, Flags=I2C_F_READ - * - * - * WriteBlock: OperationCount=2, - * LengthInBytes=1, Flags=I2C_F_SMBUS_OPERATION - * | I2C_F_WRITE - * LengthInBytes=N, Flags=I2C_F_WRITE - * WriteBlock+PEC: OperationCount=2, - * LengthInBytes=1, Flags=I2C_F_SMBUS_OPERATION - * | I2C_F_WRITE - * | I2C_F_SMBUS_PEC - * LengthInBytes=N+1, Flags=I2C_F_WRITE - */ - - request->operation_cnt = 2; - - request->operation[0].length = 1; - request->operation[0].flags = I2C_F_SMBUS_OPERATION | I2C_F_WRITE; - request->operation[0].flags |= (pec_check) ? I2C_F_SMBUS_PEC : 0; - request->operation[0].buffer = command; - - /* - * As specified in the standard, the max number of bytes to read/write - * per block operation is 32 bytes. In Golan code, the controller can - * read up to 128 bytes and write up to 127 bytes. - */ - request->operation[1].length = - (((*data_len) + (pec_check)) > I2C_SMBUS_BLOCK_MAX) ? - I2C_SMBUS_BLOCK_MAX : ((*data_len) + (pec_check)); - request->operation[1].flags = (read) ? I2C_F_READ : I2C_F_WRITE; - /* - * Skip the first data byte, which corresponds to the number of bytes - * to read/write. - */ - request->operation[1].buffer = data + 1; - - *data_len = request->operation[1].length; - - /* Set the number of byte to read. This will be used by userspace. */ - if (read) - data[0] = *data_len; -} - -static void mlx_smbus_block_func(struct mlx_smbus_request *request, - u8 *command, - u8 *data, - u8 *data_len, bool read, bool pec_check) -{ - /* - * ReadBlock: OperationCount=2, - * LengthInBytes=1, Flags=I2C_F_SMBUS_OPERATION - * | I2C_F_WRITE - * | I2C_F_SMBUS_BLOCK - * LengthInBytes=N, Flags=I2C_F_READ - * ReadBlock+PEC: OperationCount=2, - * LengthInBytes=1, Flags=I2C_F_SMBUS_OPERATION - * | I2C_F_WRITE - * | I2C_F_SMBUS_BLOCK - * | I2C_F_SMBUS_PEC - * LengthInBytes=N+1, Flags=I2C_F_READ - * - * - * WriteBlock: OperationCount=2, - * LengthInBytes=1, Flags=I2C_F_SMBUS_OPERATION - * | I2C_F_WRITE - * | I2C_F_SMBUS_BLOCK - * LengthInBytes=N, Flags=I2C_F_WRITE - * WriteBlock+PEC: OperationCount=2, - * LengthInBytes=1, Flags=I2C_F_SMBUS_OPERATION - * | I2C_F_WRITE - * | I2C_F_SMBUS_BLOCK - * | I2C_F_SMBUS_PEC - * LengthInBytes=N+1, Flags=I2C_F_WRITE - */ - - request->operation_cnt = 2; - - request->operation[0].length = 1; - request->operation[0].flags = I2C_F_SMBUS_OPERATION | I2C_F_WRITE; - request->operation[0].flags |= I2C_F_SMBUS_BLOCK; - request->operation[0].flags |= (pec_check) ? I2C_F_SMBUS_PEC : 0; - request->operation[0].buffer = command; - - request->operation[1].length = - (((*data_len) + (pec_check)) > I2C_SMBUS_BLOCK_MAX) ? - I2C_SMBUS_BLOCK_MAX : ((*data_len) + (pec_check)); - request->operation[1].flags = (read) ? I2C_F_READ : I2C_F_WRITE; - request->operation[1].buffer = data + 1; - - *data_len = request->operation[1].length; - - /* Set the number of bytes to read. This will be used by userspace. */ - if (read) - data[0] = *data_len; -} - -static void -mlx_smbus_process_call_func(struct mlx_smbus_request *request, - u8 *command, u8 *data, bool pec_check) -{ - /* - * ProcessCall: OperationCount=3, - * LengthInBytes=2, Flags=I2C_F_SMBUS_OPERATION - * | I2C_F_WRITE - * LengthInBytes=2, Flags=I2C_F_WRITE - * LengthInBytes=2, Flags=I2C_F_READ - * ProcessCall+PEC: OperationCount=3, - * LengthInBytes=1, Flags=I2C_F_SMBUS_OPERATION - * | I2C_F_WRITE - * | I2C_F_SMBUS_PEC - * LengthInBytes=2, Flags=I2C_F_WRITE - * LengthInBytes=3, Flags=I2C_F_READ - */ - - request->operation_cnt = 3; - - request->operation[0].length = 1; - request->operation[0].flags = I2C_F_SMBUS_OPERATION | I2C_F_WRITE; - request->operation[0].flags |= I2C_F_SMBUS_BLOCK; - request->operation[0].flags |= (pec_check) ? I2C_F_SMBUS_PEC : 0; - request->operation[0].buffer = command; - - request->operation[1].length = 2; - request->operation[1].flags = I2C_F_WRITE; - request->operation[1].buffer = data; - - request->operation[2].length = 3; - request->operation[2].flags = I2C_F_READ; - request->operation[2].buffer = data; -} - -static void -mlx_smbus_blk_process_call_func(struct mlx_smbus_request *request, - u8 *command, - u8 *data, u8 *data_len, bool pec_check) -{ - /* - * BlkProcessCall: OperationCount=3, - * LengthInBytes=2, Flags=I2C_F_SMBUS_OPERATION - * | I2C_F_WRITE - * | I2C_F_SMBUS_BLOCK - * LengthInBytes=N, Flags=I2C_F_WRITE - * LengthInBytes=N, Flags=I2C_F_READ - * BlkProcessCall+PEC: OperationCount=3, - * LengthInBytes=1, Flags=I2C_F_SMBUS_OPERATION - * | I2C_F_WRITE - * | I2C_F_SMBUS_BLOCK - * | I2C_F_SMBUS_PEC - * LengthInBytes=N, Flags=I2C_F_WRITE - * LengthInBytes=N+1, Flags=I2C_F_READ - */ - - u32 length; - - request->operation_cnt = 3; - - request->operation[0].length = 1; - request->operation[0].flags = I2C_F_SMBUS_OPERATION | I2C_F_WRITE; - request->operation[0].flags |= I2C_F_SMBUS_BLOCK; - request->operation[0].flags |= (pec_check) ? I2C_F_SMBUS_PEC : 0; - request->operation[0].buffer = command; - - length = (((*data_len) + (pec_check)) > I2C_SMBUS_BLOCK_MAX) ? - I2C_SMBUS_BLOCK_MAX : ((*data_len) + (pec_check)); - - request->operation[1].length = length - (pec_check); - request->operation[1].flags = I2C_F_WRITE; - request->operation[1].buffer = data; - - request->operation[2].length = length; - request->operation[2].flags = I2C_F_READ; - request->operation[2].buffer = data; - - *data_len = length; /* including PEC byte */ -} - -/* - * Initialization functions - */ - -static bool mlx_i2c_has_chip_type(struct mlx_i2c_priv *priv, u8 type) -{ - return (priv->chip->type == type); -} - -static -struct mlx_i2c_resource *mlx_i2c_get_shared_resource(struct mlx_i2c_priv *priv, - u8 type) -{ - struct mlx_chip_info *chip = priv->chip; - struct mlx_i2c_resource *res; - u8 res_idx = 0; - - for (res_idx = 0; res_idx < I2C_SHARED_RES_MAX; res_idx++) { - res = chip->shared_res[res_idx]; - if (res && (res->type == type)) - return res; - } - - return NULL; -} - -static int mlx_i2c_init_resource(struct platform_device *pdev, - struct mlx_i2c_resource **res, - u8 type) -{ - struct device *dev = &pdev->dev; - struct mlx_i2c_resource *tmp_res; - - if (!res || *res || type >= I2C_END_RES) - return -EINVAL; - - tmp_res = devm_kzalloc(dev, sizeof(struct mlx_i2c_resource), - GFP_KERNEL); - if (!tmp_res) - return -ENOMEM; - - tmp_res->params = platform_get_resource(pdev, IORESOURCE_MEM, type); - if (!tmp_res->params) { - devm_kfree(dev, tmp_res); - return -EIO; - } - - tmp_res->io = devm_ioremap_resource(dev, tmp_res->params); - if (IS_ERR(tmp_res->io)) { - devm_kfree(dev, tmp_res); - return PTR_ERR(tmp_res->io); - } - - tmp_res->type = type; - - *res = tmp_res; - - return 0; -} - -static u32 mlx_i2c_get_ticks(struct mlx_i2c_priv *priv, u64 nanoseconds, - bool minimum) -{ - u64 frequency; - u32 ticks; - - /* - * Compute ticks as follow: - * - * Ticks - * Time = --------- x 10^9 => Ticks = Time x Frequency x 10^-9 - * Frequency - * - */ - - frequency = priv->frequency; - - ticks = (nanoseconds * frequency) / 1000000000; - /* - * The number of ticks is rounded down and if minimum is equal to 1 - * then add one tick - */ - if (minimum) - ticks += 1; - - return ticks; -} - -static u32 mlx_i2c_set_timer(struct mlx_i2c_priv *priv, - u64 nsec, - bool opt, - u32 mask, - u8 offset) -{ - return ((mlx_i2c_get_ticks(priv, nsec, opt) & mask) << offset); -} - -static void mlx_i2c_set_timings(struct mlx_i2c_priv *priv, - struct mlx_i2c_timings *timings) -{ - u32 timer; - - timer = mlx_i2c_set_timer(priv, timings->scl_high, - false, 0xffff, 0); - timer |= mlx_i2c_set_timer(priv, timings->scl_low, - false, 0xffff, 16); - smbus_write(priv->smbus->io, SMBUS_TIMER_SCL_LOW_SCL_HIGH, timer); - - timer = mlx_i2c_set_timer(priv, timings->sda_rise, false, 0xff, 0); - timer |= mlx_i2c_set_timer(priv, timings->sda_fall, false, 0xff, 8); - timer |= mlx_i2c_set_timer(priv, timings->scl_rise, false, 0xff, 16); - timer |= mlx_i2c_set_timer(priv, timings->scl_fall, false, 0xff, 24); - smbus_write(priv->smbus->io, SMBUS_TIMER_FALL_RISE_SPIKE, timer); - - timer = mlx_i2c_set_timer(priv, timings->hold_start, - true, 0xffff, 0); - timer |= mlx_i2c_set_timer(priv, timings->hold_data, - true, 0xffff, 16); - smbus_write(priv->smbus->io, SMBUS_TIMER_THOLD, timer); - - timer = mlx_i2c_set_timer(priv, timings->setup_start, - true, 0xffff, 0); - timer |= mlx_i2c_set_timer(priv, timings->setup_stop, - true, 0xffff, 16); - smbus_write(priv->smbus->io, SMBUS_TIMER_TSETUP_START_STOP, timer); - - timer = mlx_i2c_set_timer(priv, timings->setup_data, true, 0xffff, 0); - smbus_write(priv->smbus->io, SMBUS_TIMER_TSETUP_DATA, timer); - - timer = mlx_i2c_set_timer(priv, timings->buf, - false, 0xffff, 0); - timer |= mlx_i2c_set_timer(priv, timings->thigh_max, - false, 0xffff, 16); - smbus_write(priv->smbus->io, SMBUS_THIGH_MAX_TBUF, timer); - - timer = timings->timeout; - smbus_write(priv->smbus->io, SMBUS_SCL_LOW_TIMEOUT, timer); -} - -static int mlx_i2c_init_timings(struct platform_device *pdev, - struct mlx_i2c_priv *priv) -{ - struct device *dev = &pdev->dev; - struct mlx_i2c_timings timings; - u32 config_khz; - int ret; - - /* - * Smbus Timing initialization - */ - - ret = device_property_read_u32(dev, "clock-frequency", &config_khz); - if (ret < 0) - config_khz = MLX_I2C_TIMING_CONFIG_HZ; - - switch (config_khz) { - default: - /* Default settings is 100 KHz */ - pr_warn("Illegal value %d: defaulting to 100 KHz\n", - config_khz); - - /* FALLTHROUGH */ - - case 100000: - timings.scl_high = SMBUS_SCL_HIGH_100KHZ; - timings.scl_low = 5000; - timings.hold_start = 4000; - timings.setup_start = 4800; - timings.setup_stop = 4000; - timings.setup_data = 250; - break; - - case 400000: - timings.scl_high = SMBUS_SCL_HIGH_400KHZ; - timings.scl_low = 1300; - timings.hold_start = 600; - timings.setup_start = 700; - timings.setup_stop = 600; - timings.setup_data = 100; - break; - - case 1000000: - timings.scl_high = SMBUS_SCL_HIGH_1000KHZ; - timings.scl_low = 1300; - timings.hold_start = 600; - timings.setup_start = 600; - timings.setup_stop = 600; - timings.setup_data = 100; - break; - } - - timings.sda_rise = timings.sda_fall = 50; - timings.scl_rise = timings.scl_fall = 50; - timings.hold_data = 300; - timings.buf = 20000; - timings.thigh_max = 5000; - /* - * Note that the SCL_LOW_TIMEOUT value is not related to the bus - * frequency, it is impacted by the time it takes the driver to - * complete data transmission before transaction abort. - */ - timings.timeout = 106500; - - mlx_i2c_set_timings(priv, &timings); - - return 0; -} - -static int mlx_i2c_get_gpio(struct platform_device *pdev, - struct mlx_i2c_priv *priv) -{ - struct device *dev = &pdev->dev; - struct mlx_i2c_resource *gpio_res; - struct resource *params; - resource_size_t size; - - gpio_res = mlx_i2c_get_shared_resource(priv, I2C_GPIO_RES); - if (!gpio_res) - return -EPERM; - - /* - * The GPIO region in TYU space is shared among I2C busses. - * This function MUST be serialized to avoid racing when - * claiming the memory region and/or setting up the GPIO. - */ - lockdep_assert_held(gpio_res->lock); - - /* Check whether the memory map exist */ - if (gpio_res->io) - return 0; - - params = gpio_res->params; - size = resource_size(params); - - if (!devm_request_mem_region(dev, params->start, size, params->name)) - return -EFAULT; - - gpio_res->io = devm_ioremap_nocache(dev, params->start, size); - if (IS_ERR(gpio_res->io)) { - devm_release_mem_region(dev, params->start, size); - return PTR_ERR(gpio_res->io); - } - - return 0; -} - -static int mlx_i2c_release_gpio(struct platform_device *pdev, - struct mlx_i2c_priv *priv) -{ - struct device *dev = &pdev->dev; - struct mlx_i2c_resource *gpio_res; - struct resource *params; - - gpio_res = mlx_i2c_get_shared_resource(priv, I2C_GPIO_RES); - if (!gpio_res) - return 0; - - mutex_lock(gpio_res->lock); - - if (gpio_res->io) { - /* Release the GPIO resource */ - params = gpio_res->params; - devm_iounmap(dev, gpio_res->io); - devm_release_mem_region(dev, params->start, - resource_size(params)); - } - - mutex_unlock(gpio_res->lock); - - return 0; -} - -static int mlx_i2c_get_corepll(struct platform_device *pdev, - struct mlx_i2c_priv *priv) -{ - struct device *dev = &pdev->dev; - struct mlx_i2c_resource *corepll_res; - struct resource *params; - resource_size_t size; - - corepll_res = mlx_i2c_get_shared_resource(priv, I2C_COREPLL_RES); - if (!corepll_res) - return -EPERM; - - /* - * The COREPLL region in TYU space is shared among I2C busses. - * This function MUST be serialized to avoid racing when - * claiming the memory region. - */ - lockdep_assert_held(corepll_res->lock); - - /* Check whether the memory map exist */ - if (corepll_res->io) - return 0; - - params = corepll_res->params; - size = resource_size(params); - - if (!devm_request_mem_region(dev, params->start, size, params->name)) - return -EFAULT; - - corepll_res->io = devm_ioremap_nocache(dev, params->start, size); - if (IS_ERR(corepll_res->io)) { - devm_release_mem_region(dev, params->start, size); - return PTR_ERR(corepll_res->io); - } - - return 0; -} - -static int mlx_i2c_release_corepll(struct platform_device *pdev, - struct mlx_i2c_priv *priv) -{ - struct device *dev = &pdev->dev; - struct mlx_i2c_resource *corepll_res; - struct resource *params; - - corepll_res = mlx_i2c_get_shared_resource(priv, I2C_COREPLL_RES); - - mutex_lock(corepll_res->lock); - - if (corepll_res->io) { - /* Release the CorePLL resource */ - params = corepll_res->params; - devm_iounmap(dev, corepll_res->io); - devm_release_mem_region(dev, params->start, - resource_size(params)); - } - - mutex_unlock(corepll_res->lock); - - return 0; -} - -static int mlx_i2c_init_master(struct platform_device *pdev, - struct mlx_i2c_priv *priv) -{ - struct device *dev = &pdev->dev; - struct mlx_i2c_resource *gpio_res; - u32 config_reg; - int ret; - - /* This configuration is only needed for BlueField 1. */ - if (!mlx_i2c_has_chip_type(priv, MLX_BLUEFIELD1_CHIP)) - return 0; - - gpio_res = mlx_i2c_get_shared_resource(priv, I2C_GPIO_RES); - if (!gpio_res) - return -EPERM; - - /* - * The GPIO region in TYU space is shared among I2C busses. - * This function MUST be serialized to avoid racing when - * claiming the memory region and/or setting up the GPIO. - */ - - mutex_lock(gpio_res->lock); - - ret = mlx_i2c_get_gpio(pdev, priv); - if (ret < 0) { - dev_err(dev, "Failed to get gpio resource"); - mutex_unlock(gpio_res->lock); - return ret; - } - - /* - * Smbus master initialization - */ - - /* - * TYU - Configuration for GPIO pins. Those pins must be asserted in - * I2C_GPIO_0_FUNC_EN_0, i.e. GPIO 0 is controlled by HW, and must - * be reset in I2C_GPIO_0_FORCE_OE_EN, i.e. GPIO_OE will be driven - * instead of HW_OE. - * For now, we do not reset the GPIO state when the driver is removed. - * First, it is not necessary to disable the bus since we are using - * the same busses. Then, some busses might be shared among Linux and - * platform firmware; disabling the bus might compromise the system - * functionality. - */ - config_reg = smbus_read(gpio_res->io, I2C_GPIO_0_FUNC_EN_0); - config_reg = I2C_GPIO_SMBUS_GW_ASSERT_PINS(priv->bus, config_reg); - smbus_write(gpio_res->io, I2C_GPIO_0_FUNC_EN_0, config_reg); - - config_reg = smbus_read(gpio_res->io, I2C_GPIO_0_FORCE_OE_EN); - config_reg = I2C_GPIO_SMBUS_GW_RESET_PINS(priv->bus, config_reg); - smbus_write(gpio_res->io, I2C_GPIO_0_FORCE_OE_EN, config_reg); - - mutex_unlock(gpio_res->lock); - - return 0; -} - -static u64 calculate_freq_from_tyu(struct mlx_i2c_resource *corepll_res) -{ - u64 core_frequency, pad_frequency; - u32 corepll_val; - u16 core_f; - u8 core_od, core_r; - - pad_frequency = BLUEFIELD_PLL_IN_FREQ; - - corepll_val = smbus_read(corepll_res->io, I2C_CORE_PLL_REG1); - - /* Get Core PLL configuration bits */ - core_f = (corepll_val >> 3) & 0x1fff; /* 13 bits */ - core_od = (corepll_val >> 16) & 0x000f; /* 4 bits */ - core_r = (corepll_val >> 20) & 0x003f; /* 6 bits */ - - /* - * Compute PLL output frequency as follow: - * - * CORE_F + 1 - * PLL_OUT_FREQ = PLL_IN_FREQ * ---------------------------- - * (CORE_R + 1) * (CORE_OD + 1) - * - * Where PLL_OUT_FREQ and PLL_IN_FREQ refer to CoreFrequency - * and PadFrequency, respectively. - */ - core_frequency = pad_frequency * (core_f + 1); - core_frequency /= ((core_r + 1) * (core_od + 1)); - - return core_frequency; -} - -static u64 calculate_freq_from_yu(struct mlx_i2c_resource *corepll_res) -{ - u64 corepll_frequency, pad_frequency; - u32 corepll_reg1_val, corepll_reg2_val; - u32 core_f; - u8 core_od, core_r; - - pad_frequency = BLUEFIELD_PLL_IN_FREQ; - - corepll_reg1_val = smbus_read(corepll_res->io, I2C_CORE_PLL_REG1); - corepll_reg2_val = smbus_read(corepll_res->io, I2C_CORE_PLL_REG2); - - /* Get Core PLL configuration bits */ - core_f = corepll_reg1_val & 0x3ffffff; /* 26 bits */ - core_r = (corepll_reg1_val >> 26) & 0x000003f; /* 6 bits */ - core_od = corepll_reg2_val & 0x000000f; /* 4 bits */ - - /* - * Compute PLL output frequency as follow: - * - * CORE_F / 16384 - * PLL_OUT_FREQ = PLL_IN_FREQ * ---------------------------- - * (CORE_R + 1) * (CORE_OD + 1) - * - * Where PLL_OUT_FREQ and PLL_IN_FREQ refer to CoreFrequency - * and PadFrequency, respectively. - */ - corepll_frequency = (pad_frequency * core_f) / 16384; - corepll_frequency /= ((core_r + 1) * (core_od + 1)); - - return corepll_frequency; -} - -static int mlx_i2c_calculate_corepll_freq(struct platform_device *pdev, - struct mlx_i2c_priv *priv) -{ - struct device *dev = &pdev->dev; - struct mlx_chip_info *chip = priv->chip; - struct mlx_i2c_resource *corepll_res; - u64 *freq = &priv->frequency; - int ret; - - corepll_res = mlx_i2c_get_shared_resource(priv, I2C_COREPLL_RES); - if (!corepll_res) - return -EPERM; - - /* - * First, check whether the TYU core Clock frequency is set. - * The TYU core frequency is the same for all I2C busses; when - * the first device gets probed the frequency is determined and - * stored into a globally visible variable. So, first of all, - * check whether the frequency is already set. Here, we assume - * that the frequency is expected to be greater than 0. - */ - mutex_lock(corepll_res->lock); - if (!corepll_frequency) { - if (!chip->calculate_freq) { - mutex_unlock(corepll_res->lock); - return -EPERM; - } - - ret = mlx_i2c_get_corepll(pdev, priv); - if (ret < 0) { - dev_err(dev, "Failed to get corePLL resource"); - mutex_unlock(corepll_res->lock); - return ret; - } - - corepll_frequency = chip->calculate_freq(corepll_res); - } - mutex_unlock(corepll_res->lock); - - *freq = corepll_frequency; - - return 0; -} - -static int mlx_slave_enable(struct mlx_i2c_priv *priv, - struct i2c_client *slave) -{ - u8 reg, reg_cnt, byte, addr_tmp; - u32 slave_reg, slave_reg_tmp; - - if (!priv) - return -EPERM; - - reg_cnt = SMBUS_SLAVE_ADDR_CNT >> 2; - - /* - * Read the slave registers. There are 4 * 32-bit slave registers. - * Each slave register can hold up to 4 * 8-bit slave configuration: - * 1) A 7-bit address - * 2) And a status bit (1 if enabled, 0 if not). - * Look for the next available slave register slot. - */ - for (reg = 0; reg < reg_cnt; reg++) { - slave_reg = smbus_read(priv->smbus->io, - SMBUS_SLAVE_ADDR_CFG + (reg * 0x4)); - /* - * Each register holds 4 slave addresses. So, we have to keep - * the byte order consistent with the value read in order to - * update the register correctly, if needed. - */ - slave_reg_tmp = slave_reg; - for (byte = 0; byte < 4; byte++) { - addr_tmp = slave_reg_tmp & 0xff; - - /* - * If an enable bit is not set in the SMBUS_SLAVE_ADDR_CFG - * register, then the slave address slot associated with - * that bit is free. So set the enable bit and write the - * slave address bits. - */ - if (!(addr_tmp & (1 << SMBUS_SLAVE_ADDR_EN_BIT))) { - slave_reg &= ~(SMBUS_SLAVE_ADDR_MASK << - (byte * 8)); - slave_reg |= (slave->addr << (byte * 8)); - slave_reg |= ((1 << SMBUS_SLAVE_ADDR_EN_BIT) - << (byte * 8)); - smbus_write(priv->smbus->io, - SMBUS_SLAVE_ADDR_CFG + (reg * 0x4), - slave_reg); - - /* - * Set the slave at the corresponding index. - */ - priv->slave[(reg * 4) + byte] = slave; - - return 0; - } - - /* Parse next byte */ - slave_reg_tmp >>= 8; - } - } - - return -EBUSY; -} - -static int mlx_slave_disable(struct mlx_i2c_priv *priv, u8 addr) -{ - u8 addr_tmp, reg, reg_cnt, byte; - u32 slave_reg, slave_reg_tmp; - - reg_cnt = SMBUS_SLAVE_ADDR_CNT >> 2; - - /* - * Read the slave registers. There are 4 * 32-bit slave registers. - * Each slave register can hold up to 4 * 8-bit slave configuration: - * 1) A 7-bit address - * 2) And a status bit (1 if enabled, 0 if not). - * Check if addr is present in the registers. - */ - for (reg = 0; reg < reg_cnt; reg++) { - slave_reg = smbus_read(priv->smbus->io, - SMBUS_SLAVE_ADDR_CFG + (reg * 0x4)); - - /* Check whether the address slots are empty */ - if (slave_reg == 0) - continue; - - /* - * Check if addr matches any of the 4 slave addresses - * in the register. - */ - slave_reg_tmp = slave_reg; - for (byte = 0; byte < 4; byte++) { - addr_tmp = slave_reg_tmp & SMBUS_SLAVE_ADDR_MASK; - /* - * Parse slave address bytes and check whether the - * slave address exists. - */ - if (addr_tmp == addr) { - /* Clear the slave address slot. */ - slave_reg &= ~(0xFF << (byte * 8)); - smbus_write(priv->smbus->io, - SMBUS_SLAVE_ADDR_CFG + (reg * 0x4), - slave_reg); - /* Free slave at the corresponding index */ - priv->slave[(reg * 4) + byte] = NULL; - - return 0; - } - - /* Parse next byte */ - slave_reg_tmp >>= 8; - } - } - - return -ENXIO; -} - -static int mlx_i2c_init_coalesce(struct platform_device *pdev, - struct mlx_i2c_priv *priv) -{ - struct mlx_i2c_resource *coalesce_res; - struct resource *params; - resource_size_t size; - int ret = 0; - - /* - * Unlike BlueField-1 platform, the coalesce registers is expected - * as a dedicated resource in the next generations of BlueField. - */ - if (mlx_i2c_has_chip_type(priv, MLX_BLUEFIELD1_CHIP)) { - coalesce_res = - mlx_i2c_get_shared_resource(priv, I2C_COALESCE_RES); - if (!coalesce_res) - return -EPERM; - - /* - * The Cause Coalesce group in TYU space is shared among - * I2C busses. This function MUST be serialized to avoid - * racing when claiming the memory region. - */ - lockdep_assert_held(g_gpio_res->lock); - - /* Check whether the memory map exist */ - if (coalesce_res->io) { - priv->coalesce = coalesce_res; - return 0; - } - - params = coalesce_res->params; - size = resource_size(params); - - if (!request_mem_region(params->start, size, params->name)) - return -EFAULT; - - coalesce_res->io = ioremap_nocache(params->start, size); - if (IS_ERR(coalesce_res->io)) { - release_mem_region(params->start, size); - return PTR_ERR(coalesce_res->io); - } - - priv->coalesce = coalesce_res; - - } else { - ret = mlx_i2c_init_resource(pdev, &priv->coalesce, - I2C_COALESCE_RES); - } - - return ret; -} - -static int mlx_i2c_release_coalesce(struct platform_device *pdev, - struct mlx_i2c_priv *priv) -{ - struct device *dev = &pdev->dev; - struct mlx_i2c_resource *coalesce_res; - struct resource *params; - resource_size_t size; - - coalesce_res = priv->coalesce; - - if (coalesce_res->io) { - params = coalesce_res->params; - size = resource_size(params); - if (mlx_i2c_has_chip_type(priv, MLX_BLUEFIELD1_CHIP)) { - mutex_lock(coalesce_res->lock); - iounmap(coalesce_res->io); - release_mem_region(params->start, size); - mutex_unlock(coalesce_res->lock); - } else { - devm_release_mem_region(dev, params->start, size); - } - } - - return 0; -} - -static int mlx_i2c_init_slave(struct platform_device *pdev, - struct mlx_i2c_priv *priv) -{ - struct device *dev = &pdev->dev; - u32 int_reg; - int ret; - - /* - * Smbus slave initialization - */ - - smbus_write(priv->smbus->io, SMBUS_SLAVE_FSM, 0); /* reset FSM */ - - /* - * Enable slave cause interrupt bits. Drive CAUSE_READ_WAIT_FW_RESPONSE - * and CAUSE_WRITE_SUCCESS, these are enabled when an external masters - * issue a Read and Write, respectively. But, clear all interrupts - * first. - */ - smbus_write(priv->slv_cause->io, I2C_CAUSE_OR_CLEAR_BITS, ~0); - int_reg = CAUSE_READ_WAIT_FW_RESPONSE | CAUSE_WRITE_SUCCESS; - smbus_write(priv->slv_cause->io, I2C_CAUSE_OR_EVTEN0_BITS, int_reg); - - /* Finally, set the 'ready' bit to start handling transactions */ - smbus_write(priv->smbus->io, SMBUS_SLAVE_READY, 0x1); - - /* Initialize the cause coalesce resource */ - ret = mlx_i2c_init_coalesce(pdev, priv); - if (ret < 0) { - dev_err(dev, "failed to initialize cause coalesce\n"); - return ret; - } - - return 0; -} - -static bool mlnx_i2c_has_coalesce(struct mlx_i2c_priv *priv, bool *read, - bool *write) -{ - struct mlx_chip_info *chip = priv->chip; - u32 coalesce0_reg, cause_reg; - u8 slave_shift, is_set; - - *read = *write = false; - - slave_shift = (chip->type != MLX_BLUEFIELD1_CHIP) ? - I2C_CAUSE_YU_SLAVE_BIT : - (priv->bus + I2C_CAUSE_TYU_SLAVE_BIT); - - coalesce0_reg = smbus_read(priv->coalesce->io, I2C_CAUSE_COALESCE_0); - is_set = coalesce0_reg & (1 << slave_shift); - - if (!is_set) - return false; - - /* Check the source of the interrupt, i.e. whether a Read or Write */ - cause_reg = smbus_read(priv->slv_cause->io, I2C_CAUSE_ARBITER_BITS); - if (cause_reg & CAUSE_READ_WAIT_FW_RESPONSE) - *read = true; - else if (cause_reg & CAUSE_WRITE_SUCCESS) - *write = true; - - /* Clear cause bits */ - smbus_write(priv->slv_cause->io, I2C_CAUSE_OR_CLEAR_BITS, ~0x0); - - return true; -} - -static bool mlx_smbus_slave_wait_for_idle(struct mlx_i2c_priv *priv, - u32 timeout) -{ - u32 addr = I2C_CAUSE_ARBITER_BITS; - u32 mask = CAUSE_S_GW_BUSY_FALL; - - if (mlx_smbus_poll(priv->slv_cause->io, addr, mask, false, timeout)) - return true; - - return false; -} - -static struct i2c_client *mlxbf_i2c_get_slave_from_addr( - struct mlx_i2c_priv *priv, - u8 addr) -{ - int i; - - for (i = 0; i < SMBUS_SLAVE_ADDR_CNT; i++) { - if (!priv->slave[i]) - continue; - - if (priv->slave[i]->addr == addr) - return priv->slave[i]; - } - - return NULL; -} - -/* - * Send byte to 'external' smbus master. This function is executed when - * an external smbus master wants to read data from the BlueField. - */ -static int mlx_smbus_irq_send(struct mlx_i2c_priv *priv, u8 recv_bytes) -{ - struct i2c_client *slave; - u8 data_desc[SLAVE_DATA_DESC_SIZE] = { 0 }; - u32 control32, data32; - u8 write_size, pec_en, addr, value, byte_cnt; - int ret = 0; - - /* - * Read the first byte received from the external master to - * determine the slave address. This byte is located in the - * first data descriptor register of the slave GW. - */ - data32 = smbus_read_data(priv->smbus->io, SLAVE_DATA_DESC_ADDR); - addr = (data32 & 0xff) >> 1; - - /* - * Check if the slave address received in the data descriptor register - * matches any of the slave addresses registered. If there is a match, - * set the slave. - */ - slave = mlxbf_i2c_get_slave_from_addr(priv, addr); - if (!slave) { - ret = -ENXIO; - goto clear_csr; - } - - /* - * An I2C read can consist of a WRITE bit transaction followed by - * a READ bit transaction. Indeed, slave devices often expect - * the slave address to be followed by the internal address. - * So, write the internal address byte first, and then, send the - * requested data to the master. - */ - if (recv_bytes > 1) { - i2c_slave_event(slave, I2C_SLAVE_WRITE_REQUESTED, &value); - - value = (data32 >> 8) & 0xff; - ret = i2c_slave_event(slave, I2C_SLAVE_WRITE_RECEIVED, - &value); - i2c_slave_event(slave, I2C_SLAVE_STOP, &value); - - if (ret < 0) - goto clear_csr; - } - - /* - * Send data to the master. Currently, the driver supports - * READ_BYTE, READ_WORD and BLOCK READ protocols. The - * hardware can send up to 128 bytes per transfer which is - * the total size of the data registers. - */ - i2c_slave_event(slave, I2C_SLAVE_READ_REQUESTED, &value); - for (byte_cnt = 0; byte_cnt < SLAVE_DATA_DESC_SIZE; byte_cnt++) { - data_desc[byte_cnt] = value; - i2c_slave_event(slave, I2C_SLAVE_READ_PROCESSED, &value); - } - - /* Send a stop condition to the backend. */ - i2c_slave_event(slave, I2C_SLAVE_STOP, &value); - - /* Set the number of bytes to write to master */ - write_size = (byte_cnt - 1) & 0x7f; - - /* Write data to Slave GW data descriptor */ - mlx_smbus_write_data(priv, data_desc, byte_cnt, SLAVE_DATA_DESC_ADDR); - - pec_en = 0; /* Disable PEC since it is not supported */ - - /* Prepare control word */ - control32 = 0; - control32 |= 0 << SLAVE_LOCK_BIT_OFF; - control32 |= 1 << SLAVE_BUSY_BIT_OFF; - control32 |= 1 << SLAVE_WRITE_BIT_OFF; - control32 |= write_size << SLAVE_WRITE_BYTES_BIT_OFF; - control32 |= pec_en << SLAVE_SEND_PEC_BIT_OFF; - - smbus_write(priv->smbus->io, SMBUS_SLAVE_GW, control32); - - /* - * Wait until the transfer is completed; the driver will wait - * until the GW is idle, a cause will rise on fall of GW busy. - */ - mlx_smbus_slave_wait_for_idle(priv, SMBUS_TIMEOUT); - -clear_csr: - /* Release the Slave GW */ - smbus_write(priv->smbus->io, SMBUS_SLAVE_RS_MASTER_BYTES, 0x0); - smbus_write(priv->smbus->io, SMBUS_SLAVE_PEC, 0x0); - smbus_write(priv->smbus->io, SMBUS_SLAVE_READY, 0x1); - - return ret; -} - -/* - * Receive bytes from 'external' smbus master. This function is executed when - * an external smbus master wants to write data to the BlueField. - */ -static int mlx_smbus_irq_recv(struct mlx_i2c_priv *priv, u8 recv_bytes) -{ - struct i2c_client *slave; - u8 data_desc[SLAVE_DATA_DESC_SIZE] = { 0 }; - u8 value, byte, addr; - int ret = 0; - - /* Read data from Slave GW data descriptor */ - mlx_smbus_read_data(priv, data_desc, recv_bytes, SLAVE_DATA_DESC_ADDR); - addr = data_desc[0] >> 1; - - /* - * Check if the slave address received in the data descriptor register - * matches any of the slave addresses registered. - */ - slave = mlxbf_i2c_get_slave_from_addr(priv, addr); - if (!slave) { - ret = -EINVAL; - goto clear_csr; - } - - /* - * Notify the slave backend that an smbus master wants to write data - * to the BlueField. - */ - i2c_slave_event(slave, I2C_SLAVE_WRITE_REQUESTED, &value); - - /* Send the received data to the slave backend. */ - for (byte = 1; byte < recv_bytes; byte++) { - value = data_desc[byte]; - ret = i2c_slave_event(slave, I2C_SLAVE_WRITE_RECEIVED, - &value); - if (ret < 0) - break; - } - - /* - * Send a stop event to the slave backend, to signal - * the end of the write transactions. - */ - i2c_slave_event(slave, I2C_SLAVE_STOP, &value); - -clear_csr: - /* Release the Slave GW */ - smbus_write(priv->smbus->io, SMBUS_SLAVE_RS_MASTER_BYTES, 0x0); - smbus_write(priv->smbus->io, SMBUS_SLAVE_PEC, 0x0); - smbus_write(priv->smbus->io, SMBUS_SLAVE_READY, 0x1); - - return ret; -} - -static irqreturn_t mlx_smbus_irq(int irq, void *ptr) -{ - struct mlx_i2c_priv *priv = ptr; - bool read, write, irq_is_set; - u32 rw_bytes_reg; - u8 recv_bytes; - - /* - * Read TYU interrupt register and determine the source of the - * interrupt. Based on the source of the interrupt one of the - * following actions are performed: - * - Receive data and send response to master. - * - Send data and release slave GW. - * - * Handle read/write transaction only. CRmaster and Iarp requests - * are ignored for now. - */ - irq_is_set = mlnx_i2c_has_coalesce(priv, &read, &write); - if (!irq_is_set || (!read && !write)) { - /* Nothing to do here, interrupt was not from this device */ - return IRQ_NONE; - } - - /* - * The SMBUS_SLAVE_RS_MASTER_BYTES includes the number of bytes - * from/to master. These are defined by 8-bits each. If the lower - * 8 bits are set, then the master expect to read N bytes from the - * slave, if the higher 8 bits are sent then the slave expect N - * bytes from the master. - */ - rw_bytes_reg = smbus_read(priv->smbus->io, SMBUS_SLAVE_RS_MASTER_BYTES); - recv_bytes = (rw_bytes_reg >> 8) & 0xff; - - /* - * For now, the slave supports 128 bytes transfer. Discard remaining - * data bytes if the master wrote more than SLAVE_DATA_DESC_SIZE, i.e, - * the actual size of the slave data descriptor. - * - * Note that we will never expect to transfer more than 128 bytes; as - * specified in the SMBus standard, block transactions cannot exceed - * 32 bytes. - */ - recv_bytes = (recv_bytes > SLAVE_DATA_DESC_SIZE) ? - SLAVE_DATA_DESC_SIZE : recv_bytes; - - if (read) - mlx_smbus_irq_send(priv, recv_bytes); - - if (write) - mlx_smbus_irq_recv(priv, recv_bytes); - - return IRQ_HANDLED; -} - -/* Return negative errno on error */ -static s32 mlx_i2c_smbus_xfer(struct i2c_adapter *adap, u16 addr, - unsigned short flags, char read_write, - u8 command, int size, - union i2c_smbus_data *data) -{ - struct mlx_smbus_request request = { 0 }; - struct mlx_i2c_priv *priv; - bool read, pec; - u8 byte_cnt; - - request.slave = addr; - - read = (read_write == I2C_SMBUS_READ); - pec = flags & I2C_FUNC_SMBUS_PEC; - - switch (size) { - case I2C_SMBUS_QUICK: - mlx_smbus_quick_command(&request, read); - dev_dbg(&adap->dev, "smbus quick, slave 0x%02x\n", addr); - break; - - case I2C_SMBUS_BYTE: - mlx_smbus_byte_func(&request, (read) ? &data->byte : &command, - read, pec); - dev_dbg(&adap->dev, "smbus %s byte, slave 0x%02x.\n", - (read) ? "read" : "write", addr); - break; - - case I2C_SMBUS_BYTE_DATA: - mlx_smbus_data_byte_func(&request, &command, &data->byte, - read, pec); - dev_dbg(&adap->dev, - "smbus %s byte data at 0x%02x, slave 0x%02x.\n", - (read) ? "read" : "write", command, addr); - break; - - case I2C_SMBUS_WORD_DATA: - mlx_smbus_data_word_func(&request, &command, - (u8 *)&data->word, read, pec); - dev_dbg(&adap->dev, - "smbus %s word data at 0x%02x, slave 0x%02x.\n", - (read) ? "read" : "write", command, addr); - break; - - case I2C_SMBUS_I2C_BLOCK_DATA: - byte_cnt = data->block[0]; - mlx_smbus_i2c_block_func(&request, &command, data->block, - &byte_cnt, read, pec); - dev_dbg(&adap->dev, - "i2c %s block data, %d bytes at 0x%02x, slave 0x%02x.\n", - (read) ? "read" : "write", byte_cnt, command, addr); - break; - - case I2C_SMBUS_BLOCK_DATA: - byte_cnt = (read) ? I2C_SMBUS_BLOCK_MAX : data->block[0]; - mlx_smbus_block_func(&request, &command, data->block, - &byte_cnt, read, pec); - dev_dbg(&adap->dev, - "smbus %s block data, %d bytes at 0x%02x, slave 0x%02x.\n", - (read) ? "read" : "write", byte_cnt, command, addr); - break; - - case I2C_FUNC_SMBUS_PROC_CALL: - mlx_smbus_process_call_func(&request, &command, - (u8 *)&data->word, pec); - dev_dbg(&adap->dev, - "process call, wr/rd at 0x%02x, slave 0x%02x.\n", - command, addr); - break; - - case I2C_FUNC_SMBUS_BLOCK_PROC_CALL: - byte_cnt = data->block[0]; - mlx_smbus_blk_process_call_func(&request, &command, - data->block, &byte_cnt, pec); - dev_dbg(&adap->dev, - "block process call, wr/rd %d bytes, slave 0x%02x.\n", - byte_cnt, addr); - break; - - default: - dev_dbg(&adap->dev, "Unsupported I2C/SMBus command %d\n", - size); - return -EOPNOTSUPP; - } - - priv = i2c_get_adapdata(adap); - - return mlx_smbus_start_transaction(priv, &request); -} - -static int mlx_i2c_reg_slave(struct i2c_client *slave) -{ - struct mlx_i2c_priv *priv = i2c_get_adapdata(slave->adapter); - struct device *dev = &slave->dev; - int ret; - - /* - * Do not support ten bit chip address and do not use Packet Error - * Checking (PEC). - */ - if (slave->flags & (I2C_CLIENT_TEN | I2C_CLIENT_PEC)) { - dev_err(dev, "SMBus PEC and 10 bit address not supported\n"); - return -EAFNOSUPPORT; - } - - ret = mlx_slave_enable(priv, slave); - - if (ret) - dev_err(dev, "Surpassed max number of registered slaves allowed\n"); - - return ret; -} - -static int mlx_i2c_unreg_slave(struct i2c_client *slave) -{ - struct mlx_i2c_priv *priv = i2c_get_adapdata(slave->adapter); - struct device *dev = &slave->dev; - int ret; - - /* - * Unregister slave by: - * 1) Disabling the slave address in hardware - * 2) Freeing priv->slave at the corresponding index - */ - ret = mlx_slave_disable(priv, slave->addr); - if (ret) - dev_err(dev, "Unable to find slave 0x%x\n", slave->addr); - - return ret; -} - -static u32 mlx_i2c_functionality(struct i2c_adapter *adap) -{ - return MLX_I2C_FUNC_ALL; -} - -static struct mlx_chip_info chip[] = { - [MLX_BLUEFIELD1_CHIP] = { - .type = MLX_BLUEFIELD1_CHIP, - .shared_res = { - [0] = &g_coalesce_res[MLX_BLUEFIELD1_CHIP], - [1] = &g_corepll_res[MLX_BLUEFIELD1_CHIP], - [2] = &g_gpio_res[MLX_BLUEFIELD1_CHIP] - }, - .calculate_freq = calculate_freq_from_tyu - }, - [MLX_BLUEFIELD2_CHIP] = { - .type = MLX_BLUEFIELD2_CHIP, - .shared_res = { - [0] = &g_corepll_res[MLX_BLUEFIELD2_CHIP] - }, - .calculate_freq = calculate_freq_from_yu - } -}; - -static const struct i2c_algorithm mlx_i2c_algo = { - .smbus_xfer = mlx_i2c_smbus_xfer, - .functionality = mlx_i2c_functionality, - .reg_slave = mlx_i2c_reg_slave, - .unreg_slave = mlx_i2c_unreg_slave, -}; - -static const struct of_device_id mlx_i2c_dt_ids[] = { - { - .compatible = "mellanox,i2c-mlxbf1", - .data = &chip[MLX_BLUEFIELD1_CHIP] - }, - { - .compatible = "mellanox,i2c-mlxbf2", - .data = &chip[MLX_BLUEFIELD2_CHIP] - }, - {}, -}; - -MODULE_DEVICE_TABLE(of, mlx_i2c_dt_ids); - -static const struct acpi_device_id mlx_i2c_acpi_ids[] = { - { "MLNXBF03", (kernel_ulong_t)&chip[MLX_BLUEFIELD1_CHIP] }, - { "MLNXBF23", (kernel_ulong_t)&chip[MLX_BLUEFIELD2_CHIP] }, - {}, -}; - -MODULE_DEVICE_TABLE(acpi, mlx_i2c_acpi_ids); - -static int mlx_i2c_acpi_probe(struct device *dev, struct mlx_i2c_priv *priv) -{ - struct acpi_device *adev; - const struct acpi_device_id *aid; - unsigned long bus_id = 0; - const char *uid; - int ret; - - if (acpi_disabled) - return -ENOENT; - - adev = ACPI_COMPANION(dev); - if (!adev) - return -ENODEV; - - aid = acpi_match_device(mlx_i2c_acpi_ids, dev); - if (!aid) - return -ENODEV; - - priv->chip = (struct mlx_chip_info *)aid->driver_data; - - uid = acpi_device_uid(adev); - if (!uid || !(*uid)) { - dev_err(dev, "cannot retrieve _UID\n"); - return -ENODEV; - } - - ret = kstrtoul(uid, 0, &bus_id); - if (ret == 0) - priv->bus = bus_id; - - return ret; -} - -static int mlx_i2c_of_probe(struct device *dev, struct mlx_i2c_priv *priv) -{ - const struct of_device_id *oid; - int bus_id = -1; - - if (IS_ENABLED(CONFIG_OF) && dev->of_node) { - oid = of_match_node(mlx_i2c_dt_ids, dev->of_node); - if (!oid) - return -ENODEV; - - priv->chip = (struct mlx_chip_info *)oid->data; - - bus_id = of_alias_get_id(dev->of_node, "i2c"); - if (bus_id >= 0) - priv->bus = bus_id; - } - - if (WARN(bus_id < 0, "couldn't get bus id")) - return bus_id; - - return 0; -} - -static int mlx_i2c_probe(struct platform_device *pdev) -{ - struct mlx_i2c_priv *priv; - struct i2c_adapter *adap; - struct device *dev = &pdev->dev; - int irq, ret; - - priv = devm_kzalloc(dev, sizeof(struct mlx_i2c_priv), GFP_KERNEL); - if (!priv) - return -ENOMEM; - - ret = mlx_i2c_acpi_probe(dev, priv); - if (ret < 0) - ret = mlx_i2c_of_probe(dev, priv); - - if (ret < 0) - return ret; - - /* Smbus region */ - ret = mlx_i2c_init_resource(pdev, &priv->smbus, - I2C_SMBUS_RES); - if (ret < 0) { - dev_err(dev, "Cannot fetch smbus resource info"); - return ret; - } - - /* Smbus master cause region */ - ret = mlx_i2c_init_resource(pdev, &priv->mst_cause, - I2C_MST_CAUSE_RES); - if (ret < 0) { - dev_err(dev, "Cannot fetch cause master resource info"); - return ret; - } - - /* Smbus slave cause region */ - ret = mlx_i2c_init_resource(pdev, &priv->slv_cause, - I2C_SLV_CAUSE_RES); - if (ret < 0) { - dev_err(dev, "Cannot fetch cause slave resource info"); - return ret; - } - - adap = &priv->adap; - adap->owner = THIS_MODULE; - adap->class = I2C_CLASS_HWMON; - adap->algo = &mlx_i2c_algo; - adap->dev.parent = dev; - adap->dev.of_node = dev->of_node; - adap->nr = priv->bus; - - snprintf(adap->name, sizeof(adap->name), "i2c%d", adap->nr); - i2c_set_adapdata(adap, priv); - - /* Read Core PLL frequency */ - ret = mlx_i2c_calculate_corepll_freq(pdev, priv); - if (ret < 0) { - dev_err(dev, "cannot get core clock frequency\n"); - /* Set to default value */ - priv->frequency = MLX_I2C_COREPLL_FREQ; - } - - /* - * Initialize master. - * Note that a physical bus might be shared among Linux and firmware - * (e.g., ATF). Thus, the bus should be initialized and ready and - * bus initialization would be unnecessary. This requires additional - * knowledge about physical busses. But, since an extra initialization - * does not really hurt, then keep the code as is. - */ - ret = mlx_i2c_init_master(pdev, priv); - if (ret < 0) { - dev_err(dev, "failed to initialize smbus master %d", - priv->bus); - return ret; - } - - /* Configure timing */ - mlx_i2c_init_timings(pdev, priv); - - /* Initialize slave gw */ - mlx_i2c_init_slave(pdev, priv); - - irq = platform_get_irq(pdev, 0); - ret = devm_request_irq(dev, irq, mlx_smbus_irq, - IRQF_ONESHOT | IRQF_SHARED | IRQF_PROBE_SHARED, - dev_name(dev), priv); - if (ret < 0) { - dev_err(dev, "cannot get irq %d\n", irq); - return ret; - } - - platform_set_drvdata(pdev, priv); - - ret = i2c_add_numbered_adapter(adap); - if (ret < 0) - return ret; - - mutex_lock(&i2c_bus_lock); - i2c_bus_count++; - mutex_unlock(&i2c_bus_lock); - dev_info(dev, "probed\n"); - - return 0; -} - -static int mlx_i2c_remove(struct platform_device *pdev) -{ - struct mlx_i2c_priv *priv = platform_get_drvdata(pdev); - struct device *dev = &pdev->dev; - struct resource *params; - - /* Release the smbus region */ - params = priv->smbus->params; - devm_release_mem_region(dev, params->start, resource_size(params)); - - /* Release the cause master region */ - params = priv->mst_cause->params; - devm_release_mem_region(dev, params->start, resource_size(params)); - - /* Release the cause slave region */ - params = priv->slv_cause->params; - devm_release_mem_region(dev, params->start, resource_size(params)); - - /* - * Release shared resources. This should be done when releasing - * the I2C controller. - */ - mutex_lock(&i2c_bus_lock); - if (--i2c_bus_count == 0) { - mlx_i2c_release_coalesce(pdev, priv); - mlx_i2c_release_corepll(pdev, priv); - mlx_i2c_release_gpio(pdev, priv); - } - mutex_unlock(&i2c_bus_lock); - - i2c_del_adapter(&priv->adap); - - return 0; -} - -static struct platform_driver mlx_i2c_driver = { - .probe = mlx_i2c_probe, - .remove = mlx_i2c_remove, - .driver = { - .name = "i2c-mlx", - .of_match_table = mlx_i2c_dt_ids, - .acpi_match_table = ACPI_PTR(mlx_i2c_acpi_ids), - }, -}; - -module_platform_driver(mlx_i2c_driver); - -MODULE_DESCRIPTION("Mellanox I2C bus driver"); -MODULE_AUTHOR("Mellanox Technologies"); -MODULE_LICENSE("GPL v2"); diff --git a/drivers/i2c/busses/i2c-mlxbf.c b/drivers/i2c/busses/i2c-mlxbf.c new file mode 100644 index 0000000..ec38fa2f --- /dev/null +++ b/drivers/i2c/busses/i2c-mlxbf.c @@ -0,0 +1,2454 @@ +// SPDX-License-Identifier: GPL-2.0 or BSD-3-Clause +/* Copyright (c) 2020 NVIDIA CORPORATION. All rights reserved. */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +/* Defines what functionality is present. */ +#define MLXBF_I2C_FUNC_SMBUS_BLOCK \ + (I2C_FUNC_SMBUS_BLOCK_DATA | I2C_FUNC_SMBUS_BLOCK_PROC_CALL) + +#define MLXBF_I2C_FUNC_SMBUS_DEFAULT \ + (I2C_FUNC_SMBUS_BYTE | I2C_FUNC_SMBUS_BYTE_DATA | \ + I2C_FUNC_SMBUS_WORD_DATA | I2C_FUNC_SMBUS_I2C_BLOCK | \ + I2C_FUNC_SMBUS_PROC_CALL) + +#define MLXBF_I2C_FUNC_ALL \ + (MLXBF_I2C_FUNC_SMBUS_DEFAULT | MLXBF_I2C_FUNC_SMBUS_BLOCK | \ + I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SLAVE) + +#define MLXBF_I2C_SMBUS_MAX 3 + +/* Shared resources info in BlueField platforms. */ + +#define MLXBF_I2C_COALESCE_TYU_ADDR 0x02801300 +#define MLXBF_I2C_COALESCE_TYU_SIZE 0x010 + +#define MLXBF_I2C_GPIO_TYU_ADDR 0x02802000 +#define MLXBF_I2C_GPIO_TYU_SIZE 0x100 + +#define MLXBF_I2C_COREPLL_TYU_ADDR 0x02800358 +#define MLXBF_I2C_COREPLL_TYU_SIZE 0x008 + +#define MLXBF_I2C_COREPLL_YU_ADDR 0x02800c30 +#define MLXBF_I2C_COREPLL_YU_SIZE 0x00c + +#define MLXBF_I2C_SHARED_RES_MAX 3 + +/* + * Note that the following SMBus, CAUSE, GPIO and PLL register addresses + * refer to their respective offsets relative to the corresponding + * memory-mapped region whose addresses are specified in either the DT or + * the ACPI tables or above. + */ + +/* + * SMBus Master core clock frequency. Timing configurations are + * strongly dependent on the core clock frequency of the SMBus + * Master. Default value is set to 400MHz. + */ +#define MLXBF_I2C_TYU_PLL_OUT_FREQ (400 * 1000 * 1000) +/* Reference clock for Bluefield - 156 MHz. */ +#define MLXBF_I2C_PLL_IN_FREQ 156250000 + +/* Constant used to determine the PLL frequency. */ +#define MLNXBF_I2C_COREPLL_CONST 16384 + +/* PLL registers. */ +#define MLXBF_I2C_CORE_PLL_REG0 0x0 +#define MLXBF_I2C_CORE_PLL_REG1 0x4 +#define MLXBF_I2C_CORE_PLL_REG2 0x8 + +/* OR cause register. */ +#define MLXBF_I2C_CAUSE_OR_EVTEN0 0x14 +#define MLXBF_I2C_CAUSE_OR_CLEAR 0x18 + +/* Arbiter Cause Register. */ +#define MLXBF_I2C_CAUSE_ARBITER 0x1c + +/* + * Cause Status flags. Note that those bits might be considered + * as interrupt enabled bits. + */ + +/* Transaction ended with STOP. */ +#define MLXBF_I2C_CAUSE_TRANSACTION_ENDED BIT(0) +/* Master arbitration lost. */ +#define MLXBF_I2C_CAUSE_M_ARBITRATION_LOST BIT(1) +/* Unexpected start detected. */ +#define MLXBF_I2C_CAUSE_UNEXPECTED_START BIT(2) +/* Unexpected stop detected. */ +#define MLXBF_I2C_CAUSE_UNEXPECTED_STOP BIT(3) +/* Wait for transfer continuation. */ +#define MLXBF_I2C_CAUSE_WAIT_FOR_FW_DATA BIT(4) +/* Failed to generate STOP. */ +#define MLXBF_I2C_CAUSE_PUT_STOP_FAILED BIT(5) +/* Failed to generate START. */ +#define MLXBF_I2C_CAUSE_PUT_START_FAILED BIT(6) +/* Clock toggle completed. */ +#define MLXBF_I2C_CAUSE_CLK_TOGGLE_DONE BIT(7) +/* Transfer timeout occurred. */ +#define MLXBF_I2C_CAUSE_M_FW_TIMEOUT BIT(8) +/* Master busy bit reset. */ +#define MLXBF_I2C_CAUSE_M_GW_BUSY_FALL BIT(9) + +#define MLXBF_I2C_CAUSE_MASTER_ARBITER_BITS_MASK GENMASK(9, 0) + +#define MLXBF_I2C_CAUSE_MASTER_STATUS_ERROR \ + (MLXBF_I2C_CAUSE_M_ARBITRATION_LOST | \ + MLXBF_I2C_CAUSE_UNEXPECTED_START | \ + MLXBF_I2C_CAUSE_UNEXPECTED_STOP | \ + MLXBF_I2C_CAUSE_PUT_STOP_FAILED | \ + MLXBF_I2C_CAUSE_PUT_START_FAILED | \ + MLXBF_I2C_CAUSE_CLK_TOGGLE_DONE | \ + MLXBF_I2C_CAUSE_M_FW_TIMEOUT) + +/* + * Slave cause status flags. Note that those bits might be considered + * as interrupt enabled bits. + */ + +/* Write transaction received successfully. */ +#define MLXBF_I2C_CAUSE_WRITE_SUCCESS BIT(0) +/* Read transaction received, waiting for response. */ +#define MLXBF_I2C_CAUSE_READ_WAIT_FW_RESPONSE BIT(13) +/* Slave busy bit reset. */ +#define MLXBF_I2C_CAUSE_S_GW_BUSY_FALL BIT(18) + +#define MLXBF_I2C_CAUSE_SLAVE_ARBITER_BITS_MASK GENMASK(20, 0) + +/* Cause coalesce registers. */ +#define MLXBF_I2C_CAUSE_COALESCE_0 0x00 +#define MLXBF_I2C_CAUSE_COALESCE_1 0x04 +#define MLXBF_I2C_CAUSE_COALESCE_2 0x08 + +#define MLXBF_I2C_CAUSE_TYU_SLAVE_BIT MLXBF_I2C_SMBUS_MAX +#define MLXBF_I2C_CAUSE_YU_SLAVE_BIT 1 + +/* Functional enable register. */ +#define MLXBF_I2C_GPIO_0_FUNC_EN_0 0x28 +/* Force OE enable register. */ +#define MLXBF_I2C_GPIO_0_FORCE_OE_EN 0x30 +/* + * Note that Smbus GWs are on GPIOs 30:25. Two pins are used to control + * SDA/SCL lines: + * + * SMBUS GW0 -> bits[26:25] + * SMBUS GW1 -> bits[28:27] + * SMBUS GW2 -> bits[30:29] + */ +#define MLXBF_I2C_GPIO_SMBUS_GW_PINS(num) (25 + ((num) << 1)) + +/* Note that gw_id can be 0,1 or 2. */ +#define MLXBF_I2C_GPIO_SMBUS_GW_MASK(num) \ + (0xffffffff & (~(0x3 << MLXBF_I2C_GPIO_SMBUS_GW_PINS(num)))) + +#define MLXBF_I2C_GPIO_SMBUS_GW_RESET_PINS(num, val) \ + ((val) & MLXBF_I2C_GPIO_SMBUS_GW_MASK(num)) + +#define MLXBF_I2C_GPIO_SMBUS_GW_ASSERT_PINS(num, val) \ + ((val) | (0x3 << MLXBF_I2C_GPIO_SMBUS_GW_PINS(num))) + +/* SMBus timing parameters. */ +#define MLXBF_I2C_SMBUS_TIMER_SCL_LOW_SCL_HIGH 0x00 +#define MLXBF_I2C_SMBUS_TIMER_FALL_RISE_SPIKE 0x04 +#define MLXBF_I2C_SMBUS_TIMER_THOLD 0x08 +#define MLXBF_I2C_SMBUS_TIMER_TSETUP_START_STOP 0x0c +#define MLXBF_I2C_SMBUS_TIMER_TSETUP_DATA 0x10 +#define MLXBF_I2C_SMBUS_THIGH_MAX_TBUF 0x14 +#define MLXBF_I2C_SMBUS_SCL_LOW_TIMEOUT 0x18 + +enum { + MLXBF_I2C_TIMING_100KHZ = 100000, + MLXBF_I2C_TIMING_400KHZ = 400000, + MLXBF_I2C_TIMING_1000KHZ = 1000000, +}; + +/* + * Defines SMBus operating frequency and core clock frequency. + * According to ADB files, default values are compliant to 100KHz SMBus + * @ 400MHz core clock. The driver should be able to calculate core + * frequency based on PLL parameters. + */ +#define MLXBF_I2C_COREPLL_FREQ MLXBF_I2C_TYU_PLL_OUT_FREQ + +/* Core PLL TYU configuration. */ +#define MLXBF_I2C_COREPLL_CORE_F_TYU_MASK GENMASK(12, 0) +#define MLXBF_I2C_COREPLL_CORE_OD_TYU_MASK GENMASK(3, 0) +#define MLXBF_I2C_COREPLL_CORE_R_TYU_MASK GENMASK(5, 0) + +#define MLXBF_I2C_COREPLL_CORE_F_TYU_SHIFT 3 +#define MLXBF_I2C_COREPLL_CORE_OD_TYU_SHIFT 16 +#define MLXBF_I2C_COREPLL_CORE_R_TYU_SHIFT 20 + +/* Core PLL YU configuration. */ +#define MLXBF_I2C_COREPLL_CORE_F_YU_MASK GENMASK(25, 0) +#define MLXBF_I2C_COREPLL_CORE_OD_YU_MASK GENMASK(3, 0) +#define MLXBF_I2C_COREPLL_CORE_R_YU_MASK GENMASK(5, 0) + +#define MLXBF_I2C_COREPLL_CORE_F_YU_SHIFT 0 +#define MLXBF_I2C_COREPLL_CORE_OD_YU_SHIFT 0 +#define MLXBF_I2C_COREPLL_CORE_R_YU_SHIFT 26 + +/* Core PLL frequency. */ +static u64 mlxbf_i2c_corepll_frequency; + +/* SMBus Master GW. */ +#define MLXBF_I2C_SMBUS_MASTER_GW 0x200 +/* Number of bytes received and sent. */ +#define MLXBF_I2C_SMBUS_RS_BYTES 0x300 +/* Packet error check (PEC) value. */ +#define MLXBF_I2C_SMBUS_MASTER_PEC 0x304 +/* Status bits (ACK/NACK/FW Timeout). */ +#define MLXBF_I2C_SMBUS_MASTER_STATUS 0x308 +/* SMbus Master Finite State Machine. */ +#define MLXBF_I2C_SMBUS_MASTER_FSM 0x310 + +/* + * When enabled, the master will issue a stop condition in case of + * timeout while waiting for FW response. + */ +#define MLXBF_I2C_SMBUS_EN_FW_TIMEOUT 0x31c + +/* SMBus master GW control bits offset in MLXBF_I2C_SMBUS_MASTER_GW[31:3]. */ +#define MLXBF_I2C_MASTER_LOCK_BIT BIT(31) /* Lock bit. */ +#define MLXBF_I2C_MASTER_BUSY_BIT BIT(30) /* Busy bit. */ +#define MLXBF_I2C_MASTER_START_BIT BIT(29) /* Control start. */ +#define MLXBF_I2C_MASTER_CTL_WRITE_BIT BIT(28) /* Control write phase. */ +#define MLXBF_I2C_MASTER_CTL_READ_BIT BIT(19) /* Control read phase. */ +#define MLXBF_I2C_MASTER_STOP_BIT BIT(3) /* Control stop. */ + +#define MLXBF_I2C_MASTER_ENABLE \ + (MLXBF_I2C_MASTER_LOCK_BIT | MLXBF_I2C_MASTER_BUSY_BIT | \ + MLXBF_I2C_MASTER_START_BIT | MLXBF_I2C_MASTER_STOP_BIT) + +#define MLXBF_I2C_MASTER_ENABLE_WRITE \ + (MLXBF_I2C_MASTER_ENABLE | MLXBF_I2C_MASTER_CTL_WRITE_BIT) + +#define MLXBF_I2C_MASTER_ENABLE_READ \ + (MLXBF_I2C_MASTER_ENABLE | MLXBF_I2C_MASTER_CTL_READ_BIT) + +#define MLXBF_I2C_MASTER_SLV_ADDR_SHIFT 12 /* Slave address shift. */ +#define MLXBF_I2C_MASTER_WRITE_SHIFT 21 /* Control write bytes shift. */ +#define MLXBF_I2C_MASTER_SEND_PEC_SHIFT 20 /* Send PEC byte shift. */ +#define MLXBF_I2C_MASTER_PARSE_EXP_SHIFT 11 /* Parse expected bytes shift. */ +#define MLXBF_I2C_MASTER_READ_SHIFT 4 /* Control read bytes shift. */ + +/* SMBus master GW Data descriptor. */ +#define MLXBF_I2C_MASTER_DATA_DESC_ADDR 0x280 +#define MLXBF_I2C_MASTER_DATA_DESC_SIZE 0x80 /* Size in bytes. */ + +/* Maximum bytes to read/write per SMBus transaction. */ +#define MLXBF_I2C_MASTER_DATA_R_LENGTH MLXBF_I2C_MASTER_DATA_DESC_SIZE +#define MLXBF_I2C_MASTER_DATA_W_LENGTH (MLXBF_I2C_MASTER_DATA_DESC_SIZE - 1) + +/* All bytes were transmitted. */ +#define MLXBF_I2C_SMBUS_STATUS_BYTE_CNT_DONE BIT(0) +/* NACK received. */ +#define MLXBF_I2C_SMBUS_STATUS_NACK_RCV BIT(1) +/* Slave's byte count >128 bytes. */ +#define MLXBF_I2C_SMBUS_STATUS_READ_ERR BIT(2) +/* Timeout occurred. */ +#define MLXBF_I2C_SMBUS_STATUS_FW_TIMEOUT BIT(3) + +#define MLXBF_I2C_SMBUS_MASTER_STATUS_MASK GENMASK(3, 0) + +#define MLXBF_I2C_SMBUS_MASTER_STATUS_ERROR \ + (MLXBF_I2C_SMBUS_STATUS_NACK_RCV | \ + MLXBF_I2C_SMBUS_STATUS_READ_ERR | \ + MLXBF_I2C_SMBUS_STATUS_FW_TIMEOUT) + +#define MLXBF_I2C_SMBUS_MASTER_FSM_STOP_MASK BIT(31) +#define MLXBF_I2C_SMBUS_MASTER_FSM_PS_STATE_MASK BIT(15) + +/* SMBus slave GW. */ +#define MLXBF_I2C_SMBUS_SLAVE_GW 0x400 +/* Number of bytes received and sent from/to master. */ +#define MLXBF_I2C_SMBUS_SLAVE_RS_MASTER_BYTES 0x500 +/* Packet error check (PEC) value. */ +#define MLXBF_I2C_SMBUS_SLAVE_PEC 0x504 +/* SMBus slave Finite State Machine (FSM). */ +#define MLXBF_I2C_SMBUS_SLAVE_FSM 0x510 +/* + * Should be set when all raised causes handled, and cleared by HW on + * every new cause. + */ +#define MLXBF_I2C_SMBUS_SLAVE_READY 0x52c + +/* SMBus slave GW control bits offset in MLXBF_I2C_SMBUS_SLAVE_GW[31:19]. */ +#define MLXBF_I2C_SLAVE_BUSY_BIT BIT(30) /* Busy bit. */ +#define MLXBF_I2C_SLAVE_WRITE_BIT BIT(29) /* Control write enable. */ + +#define MLXBF_I2C_SLAVE_ENABLE \ + (MLXBF_I2C_SLAVE_BUSY_BIT | MLXBF_I2C_SLAVE_WRITE_BIT) + +#define MLXBF_I2C_SLAVE_WRITE_BYTES_SHIFT 22 /* Number of bytes to write. */ +#define MLXBF_I2C_SLAVE_SEND_PEC_SHIFT 21 /* Send PEC byte shift. */ + +/* SMBus slave GW Data descriptor. */ +#define MLXBF_I2C_SLAVE_DATA_DESC_ADDR 0x480 +#define MLXBF_I2C_SLAVE_DATA_DESC_SIZE 0x80 /* Size in bytes. */ + +/* SMbus slave configuration registers. */ +#define MLXBF_I2C_SMBUS_SLAVE_ADDR_CFG 0x514 +#define MLXBF_I2C_SMBUS_SLAVE_ADDR_CNT 16 +#define MLXBF_I2C_SMBUS_SLAVE_ADDR_EN_BIT 7 +#define MLXBF_I2C_SMBUS_SLAVE_ADDR_MASK GENMASK(6, 0) + +#define MLXBF_I2C_SLAVE_ADDR_ENABLED(addr) \ + ((addr) & (1 << MLXBF_I2C_SMBUS_SLAVE_ADDR_EN_BIT)) + +/* + * Timeout is given in microsends. Note also that timeout handling is not + * exact. + */ +#define MLXBF_I2C_SMBUS_TIMEOUT (300 * 1000) /* 300ms */ + +/* Encapsulates timing parameters. */ +struct mlxbf_i2c_timings { + u16 scl_high; /* Clock high period. */ + u16 scl_low; /* Clock low period. */ + u8 sda_rise; /* Data rise time. */ + u8 sda_fall; /* Data fall time. */ + u8 scl_rise; /* Clock rise time. */ + u8 scl_fall; /* Clock fall time. */ + u16 hold_start; /* Hold time after (REPEATED) START. */ + u16 hold_data; /* Data hold time. */ + u16 setup_start; /* REPEATED START condition setup time. */ + u16 setup_stop; /* STOP condition setup time. */ + u16 setup_data; /* Data setup time. */ + u16 pad; /* Padding. */ + u16 buf; /* Bus free time between STOP and START. */ + u16 thigh_max; /* Thigh max. */ + u32 timeout; /* Detect clock low timeout. */ +}; + +enum { + MLXBF_I2C_F_READ = BIT(0), + MLXBF_I2C_F_WRITE = BIT(1), + MLXBF_I2C_F_NORESTART = BIT(3), + MLXBF_I2C_F_SMBUS_OPERATION = BIT(4), + MLXBF_I2C_F_SMBUS_BLOCK = BIT(5), + MLXBF_I2C_F_SMBUS_PEC = BIT(6), + MLXBF_I2C_F_SMBUS_PROCESS_CALL = BIT(7), +}; + +struct mlxbf_i2c_smbus_operation { + u32 flags; + u32 length; /* Buffer length in bytes. */ + u8 *buffer; +}; + +#define MLXBF_I2C_SMBUS_OP_CNT_1 1 +#define MLXBF_I2C_SMBUS_OP_CNT_2 2 +#define MLXBF_I2C_SMBUS_OP_CNT_3 3 +#define MLXBF_I2C_SMBUS_MAX_OP_CNT MLXBF_I2C_SMBUS_OP_CNT_3 + +struct mlxbf_i2c_smbus_request { + u8 slave; + u8 operation_cnt; + struct mlxbf_i2c_smbus_operation operation[MLXBF_I2C_SMBUS_MAX_OP_CNT]; +}; + +struct mlxbf_i2c_resource { + void __iomem *io; + struct resource *params; + struct mutex *lock; /* Mutex to protect mlxbf_i2c_resource. */ + u8 type; +}; + +/* List of chip resources that are being accessed by the driver. */ +enum { + MLXBF_I2C_SMBUS_RES, + MLXBF_I2C_MST_CAUSE_RES, + MLXBF_I2C_SLV_CAUSE_RES, + MLXBF_I2C_COALESCE_RES, + MLXBF_I2C_COREPLL_RES, + MLXBF_I2C_GPIO_RES, + MLXBF_I2C_END_RES, +}; + +/* Helper macro to define an I2C resource parameters. */ +#define MLXBF_I2C_RES_PARAMS(addr, size, str) \ + { \ + .start = (addr), \ + .end = (addr) + (size) - 1, \ + .name = (str) \ + } + +static struct resource mlxbf_i2c_coalesce_tyu_params = + MLXBF_I2C_RES_PARAMS(MLXBF_I2C_COALESCE_TYU_ADDR, + MLXBF_I2C_COALESCE_TYU_SIZE, + "COALESCE_MEM"); +static struct resource mlxbf_i2c_corepll_tyu_params = + MLXBF_I2C_RES_PARAMS(MLXBF_I2C_COREPLL_TYU_ADDR, + MLXBF_I2C_COREPLL_TYU_SIZE, + "COREPLL_MEM"); +static struct resource mlxbf_i2c_corepll_yu_params = + MLXBF_I2C_RES_PARAMS(MLXBF_I2C_COREPLL_YU_ADDR, + MLXBF_I2C_COREPLL_YU_SIZE, + "COREPLL_MEM"); +static struct resource mlxbf_i2c_gpio_tyu_params = + MLXBF_I2C_RES_PARAMS(MLXBF_I2C_GPIO_TYU_ADDR, + MLXBF_I2C_GPIO_TYU_SIZE, + "GPIO_MEM"); + +static struct mutex mlxbf_i2c_coalesce_lock; +static struct mutex mlxbf_i2c_corepll_lock; +static struct mutex mlxbf_i2c_gpio_lock; + +/* Mellanox BlueField chip type. */ +enum mlxbf_i2c_chip_type { + MLXBF_I2C_CHIP_TYPE_1, /* Mellanox BlueField-1 chip. */ + MLXBF_I2C_CHIP_TYPE_2, /* Mallanox BlueField-2 chip. */ +}; + +struct mlxbf_i2c_chip_info { + enum mlxbf_i2c_chip_type type; + /* Chip shared resources that are being used by the I2C controller. */ + struct mlxbf_i2c_resource *shared_res[MLXBF_I2C_SHARED_RES_MAX]; + + /* Callback to calculate the core PLL frequency. */ + u64 (*calculate_freq)(struct mlxbf_i2c_resource *corepll_res); +}; + +struct mlxbf_i2c_priv { + const struct mlxbf_i2c_chip_info *chip; + struct i2c_adapter adap; + struct mlxbf_i2c_resource *smbus; + struct mlxbf_i2c_resource *mst_cause; + struct mlxbf_i2c_resource *slv_cause; + struct mlxbf_i2c_resource *coalesce; + u64 frequency; /* Core frequency in Hz. */ + int bus; /* Physical bus identifier. */ + int irq; + struct i2c_client *slave[MLXBF_I2C_SMBUS_SLAVE_ADDR_CNT]; +}; + +static struct mlxbf_i2c_resource mlxbf_i2c_coalesce_res[] = { + [MLXBF_I2C_CHIP_TYPE_1] = { + .params = &mlxbf_i2c_coalesce_tyu_params, + .lock = &mlxbf_i2c_coalesce_lock, + .type = MLXBF_I2C_COALESCE_RES + }, + {} +}; + +static struct mlxbf_i2c_resource mlxbf_i2c_corepll_res[] = { + [MLXBF_I2C_CHIP_TYPE_1] = { + .params = &mlxbf_i2c_corepll_tyu_params, + .lock = &mlxbf_i2c_corepll_lock, + .type = MLXBF_I2C_COREPLL_RES + }, + [MLXBF_I2C_CHIP_TYPE_2] = { + .params = &mlxbf_i2c_corepll_yu_params, + .lock = &mlxbf_i2c_corepll_lock, + .type = MLXBF_I2C_COREPLL_RES, + } +}; + +static struct mlxbf_i2c_resource mlxbf_i2c_gpio_res[] = { + [MLXBF_I2C_CHIP_TYPE_1] = { + .params = &mlxbf_i2c_gpio_tyu_params, + .lock = &mlxbf_i2c_gpio_lock, + .type = MLXBF_I2C_GPIO_RES + }, + {} +}; + +static u8 mlxbf_i2c_bus_count; + +static struct mutex mlxbf_i2c_bus_lock; + +/* Polling frequency in microseconds. */ +#define MLXBF_I2C_POLL_FREQ_IN_USEC 200 + +#define MLXBF_I2C_SHIFT_0 0 +#define MLXBF_I2C_SHIFT_8 8 +#define MLXBF_I2C_SHIFT_16 16 +#define MLXBF_I2C_SHIFT_24 24 + +#define MLXBF_I2C_MASK_8 GENMASK(7, 0) +#define MLXBF_I2C_MASK_16 GENMASK(15, 0) + +#define MLXBF_I2C_FREQUENCY_1GHZ 1000000000 + +/* + * Function to poll a set of bits at a specific address; it checks whether + * the bits are equal to zero when eq_zero is set to 'true', and not equal + * to zero when eq_zero is set to 'false'. + * Note that the timeout is given in microseconds. + */ +static u32 mlxbf_smbus_poll(void __iomem *io, u32 addr, u32 mask, + bool eq_zero, u32 timeout) +{ + u32 bits; + + timeout = (timeout / MLXBF_I2C_POLL_FREQ_IN_USEC) + 1; + + do { + bits = readl(io + addr) & mask; + if (eq_zero ? bits == 0 : bits != 0) + return eq_zero ? 1 : bits; + udelay(MLXBF_I2C_POLL_FREQ_IN_USEC); + } while (timeout-- != 0); + + return 0; +} + +/* + * SW must make sure that the SMBus Master GW is idle before starting + * a transaction. Accordingly, this function polls the Master FSM stop + * bit; it returns false when the bit is asserted, true if not. + */ +static bool mlxbf_smbus_master_wait_for_idle(struct mlxbf_i2c_priv *priv) +{ + u32 mask = MLXBF_I2C_SMBUS_MASTER_FSM_STOP_MASK; + u32 addr = MLXBF_I2C_SMBUS_MASTER_FSM; + u32 timeout = MLXBF_I2C_SMBUS_TIMEOUT; + + if (mlxbf_smbus_poll(priv->smbus->io, addr, mask, true, timeout)) + return true; + + return false; +} + +static bool mlxbf_i2c_smbus_transaction_success(u32 master_status, + u32 cause_status) +{ + /* + * When transaction ended with STOP, all bytes were transmitted, + * and no NACK received, then the transaction ended successfully. + * On the other hand, when the GW is configured with the stop bit + * de-asserted then the SMBus expects the following GW configuration + * for transfer continuation. + */ + if ((cause_status & MLXBF_I2C_CAUSE_WAIT_FOR_FW_DATA) || + ((cause_status & MLXBF_I2C_CAUSE_TRANSACTION_ENDED) && + (master_status & MLXBF_I2C_SMBUS_STATUS_BYTE_CNT_DONE) && + !(master_status & MLXBF_I2C_SMBUS_STATUS_NACK_RCV))) + return true; + + return false; +} + +/* + * Poll SMBus master status and return transaction status, + * i.e. whether succeeded or failed. I2C and SMBus fault codes + * are returned as negative numbers from most calls, with zero + * or some positive number indicating a non-fault return. + */ +static int mlxbf_i2c_smbus_check_status(struct mlxbf_i2c_priv *priv) +{ + u32 master_status_bits; + u32 cause_status_bits; + + /* + * GW busy bit is raised by the driver and cleared by the HW + * when the transaction is completed. The busy bit is a good + * indicator of transaction status. So poll the busy bit, and + * then read the cause and master status bits to determine if + * errors occurred during the transaction. + */ + mlxbf_smbus_poll(priv->smbus->io, MLXBF_I2C_SMBUS_MASTER_GW, + MLXBF_I2C_MASTER_BUSY_BIT, true, + MLXBF_I2C_SMBUS_TIMEOUT); + + /* Read cause status bits. */ + cause_status_bits = readl(priv->mst_cause->io + + MLXBF_I2C_CAUSE_ARBITER); + cause_status_bits &= MLXBF_I2C_CAUSE_MASTER_ARBITER_BITS_MASK; + + /* + * Parse both Cause and Master GW bits, then return transaction status. + */ + + master_status_bits = readl(priv->smbus->io + + MLXBF_I2C_SMBUS_MASTER_STATUS); + master_status_bits &= MLXBF_I2C_SMBUS_MASTER_STATUS_MASK; + + if (mlxbf_i2c_smbus_transaction_success(master_status_bits, + cause_status_bits)) + return 0; + + /* + * In case of timeout on GW busy, the ISR will clear busy bit but + * transaction ended bits cause will not be set so the transaction + * fails. Then, we must check Master GW status bits. + */ + if ((master_status_bits & MLXBF_I2C_SMBUS_MASTER_STATUS_ERROR) && + (cause_status_bits & (MLXBF_I2C_CAUSE_TRANSACTION_ENDED | + MLXBF_I2C_CAUSE_M_GW_BUSY_FALL))) + return -EIO; + + if (cause_status_bits & MLXBF_I2C_CAUSE_MASTER_STATUS_ERROR) + return -EAGAIN; + + return -ETIMEDOUT; +} + +static void mlxbf_i2c_smbus_write_data(struct mlxbf_i2c_priv *priv, + const u8 *data, u8 length, u32 addr) +{ + u8 offset, aligned_length; + u32 data32; + + aligned_length = round_up(length, 4); + + /* + * Copy data bytes from 4-byte aligned source buffer. + * Data copied to the Master GW Data Descriptor MUST be shifted + * left so the data starts at the MSB of the descriptor registers + * as required by the underlying hardware. Enable byte swapping + * when writing data bytes to the 32 * 32-bit HW Data registers + * a.k.a Master GW Data Descriptor. + */ + for (offset = 0; offset < aligned_length; offset += sizeof(u32)) { + data32 = *((u32 *)(data + offset)); + iowrite32be(data32, priv->smbus->io + addr + offset); + } +} + +static void mlxbf_i2c_smbus_read_data(struct mlxbf_i2c_priv *priv, + u8 *data, u8 length, u32 addr) +{ + u32 data32, mask; + u8 byte, offset; + + mask = sizeof(u32) - 1; + + /* + * Data bytes in the Master GW Data Descriptor are shifted left + * so the data starts at the MSB of the descriptor registers as + * set by the underlying hardware. Enable byte swapping while + * reading data bytes from the 32 * 32-bit HW Data registers + * a.k.a Master GW Data Descriptor. + */ + + for (offset = 0; offset < (length & ~mask); offset += sizeof(u32)) { + data32 = ioread32be(priv->smbus->io + addr + offset); + *((u32 *)(data + offset)) = data32; + } + + if (!(length & mask)) + return; + + data32 = ioread32be(priv->smbus->io + addr + offset); + + for (byte = 0; byte < (length & mask); byte++) { + data[offset + byte] = data32 & GENMASK(7, 0); + data32 = ror32(data32, MLXBF_I2C_SHIFT_8); + } +} + +static int mlxbf_i2c_smbus_enable(struct mlxbf_i2c_priv *priv, u8 slave, + u8 len, u8 block_en, u8 pec_en, bool read) +{ + u32 command; + + /* Set Master GW control word. */ + if (read) { + command = MLXBF_I2C_MASTER_ENABLE_READ; + command |= rol32(len, MLXBF_I2C_MASTER_READ_SHIFT); + } else { + command = MLXBF_I2C_MASTER_ENABLE_WRITE; + command |= rol32(len, MLXBF_I2C_MASTER_WRITE_SHIFT); + } + command |= rol32(slave, MLXBF_I2C_MASTER_SLV_ADDR_SHIFT); + command |= rol32(block_en, MLXBF_I2C_MASTER_PARSE_EXP_SHIFT); + command |= rol32(pec_en, MLXBF_I2C_MASTER_SEND_PEC_SHIFT); + + /* Clear status bits. */ + writel(0x0, priv->smbus->io + MLXBF_I2C_SMBUS_MASTER_STATUS); + /* Set the cause data. */ + writel(~0x0, priv->smbus->io + MLXBF_I2C_CAUSE_OR_CLEAR); + /* Zero PEC byte. */ + writel(0x0, priv->smbus->io + MLXBF_I2C_SMBUS_MASTER_PEC); + /* Zero byte count. */ + writel(0x0, priv->smbus->io + MLXBF_I2C_SMBUS_RS_BYTES); + + /* GW activation. */ + writel(command, priv->smbus->io + MLXBF_I2C_SMBUS_MASTER_GW); + + /* + * Poll master status and check status bits. An ACK is sent when + * completing writing data to the bus (Master 'byte_count_done' bit + * is set to 1). + */ + return mlxbf_i2c_smbus_check_status(priv); +} + +static int +mlxbf_i2c_smbus_start_transaction(struct mlxbf_i2c_priv *priv, + struct mlxbf_i2c_smbus_request *request) +{ + u8 data_desc[MLXBF_I2C_MASTER_DATA_DESC_SIZE] = { 0 }; + u8 op_idx, data_idx, data_len, write_len, read_len; + struct mlxbf_i2c_smbus_operation *operation; + u8 read_en, write_en, block_en, pec_en; + u8 slave, flags, addr; + u8 *read_buf; + int ret = 0; + + if (request->operation_cnt > MLXBF_I2C_SMBUS_MAX_OP_CNT) + return -EINVAL; + + read_buf = NULL; + data_idx = 0; + read_en = 0; + write_en = 0; + write_len = 0; + read_len = 0; + block_en = 0; + pec_en = 0; + slave = request->slave & GENMASK(6, 0); + addr = slave << 1; + + /* First of all, check whether the HW is idle. */ + if (WARN_ON(!mlxbf_smbus_master_wait_for_idle(priv))) + return -EBUSY; + + /* Set first byte. */ + data_desc[data_idx++] = addr; + + for (op_idx = 0; op_idx < request->operation_cnt; op_idx++) { + operation = &request->operation[op_idx]; + flags = operation->flags; + + /* + * Note that read and write operations might be handled by a + * single command. If the MLXBF_I2C_F_SMBUS_OPERATION is set + * then write command byte and set the optional SMBus specific + * bits such as block_en and pec_en. These bits MUST be + * submitted by the first operation only. + */ + if (op_idx == 0 && flags & MLXBF_I2C_F_SMBUS_OPERATION) { + block_en = flags & MLXBF_I2C_F_SMBUS_BLOCK; + pec_en = flags & MLXBF_I2C_F_SMBUS_PEC; + } + + if (flags & MLXBF_I2C_F_WRITE) { + write_en = 1; + write_len += operation->length; + memcpy(data_desc + data_idx, + operation->buffer, operation->length); + data_idx += operation->length; + } + /* + * We assume that read operations are performed only once per + * SMBus transaction. *TBD* protect this statement so it won't + * be executed twice? or return an error if we try to read more + * than once? + */ + if (flags & MLXBF_I2C_F_READ) { + read_en = 1; + /* Subtract 1 as required by HW. */ + read_len = operation->length - 1; + read_buf = operation->buffer; + } + } + + /* Set Master GW data descriptor. */ + data_len = write_len + 1; /* Add one byte of the slave address. */ + /* + * Note that data_len cannot be 0. Indeed, the slave address byte + * must be written to the data registers. + */ + mlxbf_i2c_smbus_write_data(priv, (const u8 *)data_desc, data_len, + MLXBF_I2C_MASTER_DATA_DESC_ADDR); + + if (write_en) { + ret = mlxbf_i2c_smbus_enable(priv, slave, write_len, block_en, + pec_en, 0); + if (ret) + return ret; + } + + if (read_en) { + /* Write slave address to Master GW data descriptor. */ + mlxbf_i2c_smbus_write_data(priv, (const u8 *)&addr, 1, + MLXBF_I2C_MASTER_DATA_DESC_ADDR); + ret = mlxbf_i2c_smbus_enable(priv, slave, read_len, block_en, + pec_en, 1); + if (!ret) { + /* Get Master GW data descriptor. */ + mlxbf_i2c_smbus_read_data(priv, data_desc, read_len + 1, + MLXBF_I2C_MASTER_DATA_DESC_ADDR); + + /* Get data from Master GW data descriptor. */ + memcpy(read_buf, data_desc, read_len + 1); + } + + /* + * After a read operation the SMBus FSM ps (present state) + * needs to be 'manually' reset. This should be removed in + * next tag integration. + */ + writel(MLXBF_I2C_SMBUS_MASTER_FSM_PS_STATE_MASK, + priv->smbus->io + MLXBF_I2C_SMBUS_MASTER_FSM); + } + + return ret; +} + +/* I2C SMBus protocols. */ + +static void +mlxbf_i2c_smbus_quick_command(struct mlxbf_i2c_smbus_request *request, + u8 read) +{ + request->operation_cnt = MLXBF_I2C_SMBUS_OP_CNT_1; + + request->operation[0].length = 0; + request->operation[0].flags = MLXBF_I2C_F_WRITE; + request->operation[0].flags |= read ? MLXBF_I2C_F_READ : 0; +} + +static void mlxbf_i2c_smbus_byte_func(struct mlxbf_i2c_smbus_request *request, + u8 *data, bool read, bool pec_check) +{ + request->operation_cnt = MLXBF_I2C_SMBUS_OP_CNT_1; + + request->operation[0].length = 1; + request->operation[0].length += pec_check; + + request->operation[0].flags = MLXBF_I2C_F_SMBUS_OPERATION; + request->operation[0].flags |= read ? + MLXBF_I2C_F_READ : MLXBF_I2C_F_WRITE; + request->operation[0].flags |= pec_check ? MLXBF_I2C_F_SMBUS_PEC : 0; + + request->operation[0].buffer = data; +} + +static void +mlxbf_i2c_smbus_data_byte_func(struct mlxbf_i2c_smbus_request *request, + u8 *command, u8 *data, bool read, bool pec_check) +{ + request->operation_cnt = MLXBF_I2C_SMBUS_OP_CNT_2; + + request->operation[0].length = 1; + request->operation[0].flags = + MLXBF_I2C_F_SMBUS_OPERATION | MLXBF_I2C_F_WRITE; + request->operation[0].flags |= pec_check ? MLXBF_I2C_F_SMBUS_PEC : 0; + request->operation[0].buffer = command; + + request->operation[1].length = 1; + request->operation[1].length += pec_check; + request->operation[1].flags = read ? + MLXBF_I2C_F_READ : MLXBF_I2C_F_WRITE; + request->operation[1].buffer = data; +} + +static void +mlxbf_i2c_smbus_data_word_func(struct mlxbf_i2c_smbus_request *request, + u8 *command, u8 *data, bool read, bool pec_check) +{ + request->operation_cnt = MLXBF_I2C_SMBUS_OP_CNT_2; + + request->operation[0].length = 1; + request->operation[0].flags = + MLXBF_I2C_F_SMBUS_OPERATION | MLXBF_I2C_F_WRITE; + request->operation[0].flags |= pec_check ? MLXBF_I2C_F_SMBUS_PEC : 0; + request->operation[0].buffer = command; + + request->operation[1].length = 2; + request->operation[1].length += pec_check; + request->operation[1].flags = read ? + MLXBF_I2C_F_READ : MLXBF_I2C_F_WRITE; + request->operation[1].buffer = data; +} + +static void +mlxbf_i2c_smbus_i2c_block_func(struct mlxbf_i2c_smbus_request *request, + u8 *command, u8 *data, u8 *data_len, bool read, + bool pec_check) +{ + request->operation_cnt = MLXBF_I2C_SMBUS_OP_CNT_2; + + request->operation[0].length = 1; + request->operation[0].flags = + MLXBF_I2C_F_SMBUS_OPERATION | MLXBF_I2C_F_WRITE; + request->operation[0].flags |= pec_check ? MLXBF_I2C_F_SMBUS_PEC : 0; + request->operation[0].buffer = command; + + /* + * As specified in the standard, the max number of bytes to read/write + * per block operation is 32 bytes. In Golan code, the controller can + * read up to 128 bytes and write up to 127 bytes. + */ + request->operation[1].length = + (*data_len + pec_check > I2C_SMBUS_BLOCK_MAX) ? + I2C_SMBUS_BLOCK_MAX : *data_len + pec_check; + request->operation[1].flags = read ? + MLXBF_I2C_F_READ : MLXBF_I2C_F_WRITE; + /* + * Skip the first data byte, which corresponds to the number of bytes + * to read/write. + */ + request->operation[1].buffer = data + 1; + + *data_len = request->operation[1].length; + + /* Set the number of byte to read. This will be used by userspace. */ + if (read) + data[0] = *data_len; +} + +static void mlxbf_i2c_smbus_block_func(struct mlxbf_i2c_smbus_request *request, + u8 *command, u8 *data, u8 *data_len, + bool read, bool pec_check) +{ + request->operation_cnt = MLXBF_I2C_SMBUS_OP_CNT_2; + + request->operation[0].length = 1; + request->operation[0].flags = + MLXBF_I2C_F_SMBUS_OPERATION | MLXBF_I2C_F_WRITE; + request->operation[0].flags |= MLXBF_I2C_F_SMBUS_BLOCK; + request->operation[0].flags |= pec_check ? MLXBF_I2C_F_SMBUS_PEC : 0; + request->operation[0].buffer = command; + + request->operation[1].length = + (*data_len + pec_check > I2C_SMBUS_BLOCK_MAX) ? + I2C_SMBUS_BLOCK_MAX : *data_len + pec_check; + request->operation[1].flags = read ? + MLXBF_I2C_F_READ : MLXBF_I2C_F_WRITE; + request->operation[1].buffer = data + 1; + + *data_len = request->operation[1].length; + + /* Set the number of bytes to read. This will be used by userspace. */ + if (read) + data[0] = *data_len; +} + +static void +mlxbf_i2c_smbus_process_call_func(struct mlxbf_i2c_smbus_request *request, + u8 *command, u8 *data, bool pec_check) +{ + request->operation_cnt = MLXBF_I2C_SMBUS_OP_CNT_3; + + request->operation[0].length = 1; + request->operation[0].flags = + MLXBF_I2C_F_SMBUS_OPERATION | MLXBF_I2C_F_WRITE; + request->operation[0].flags |= MLXBF_I2C_F_SMBUS_BLOCK; + request->operation[0].flags |= pec_check ? MLXBF_I2C_F_SMBUS_PEC : 0; + request->operation[0].buffer = command; + + request->operation[1].length = 2; + request->operation[1].flags = MLXBF_I2C_F_WRITE; + request->operation[1].buffer = data; + + request->operation[2].length = 3; + request->operation[2].flags = MLXBF_I2C_F_READ; + request->operation[2].buffer = data; +} + +static void +mlxbf_i2c_smbus_blk_process_call_func(struct mlxbf_i2c_smbus_request *request, + u8 *command, u8 *data, u8 *data_len, + bool pec_check) +{ + u32 length; + + request->operation_cnt = MLXBF_I2C_SMBUS_OP_CNT_3; + + request->operation[0].length = 1; + request->operation[0].flags = + MLXBF_I2C_F_SMBUS_OPERATION | MLXBF_I2C_F_WRITE; + request->operation[0].flags |= MLXBF_I2C_F_SMBUS_BLOCK; + request->operation[0].flags |= (pec_check) ? MLXBF_I2C_F_SMBUS_PEC : 0; + request->operation[0].buffer = command; + + length = (*data_len + pec_check > I2C_SMBUS_BLOCK_MAX) ? + I2C_SMBUS_BLOCK_MAX : *data_len + pec_check; + + request->operation[1].length = length - pec_check; + request->operation[1].flags = MLXBF_I2C_F_WRITE; + request->operation[1].buffer = data; + + request->operation[2].length = length; + request->operation[2].flags = MLXBF_I2C_F_READ; + request->operation[2].buffer = data; + + *data_len = length; /* including PEC byte. */ +} + +/* Initialization functions. */ + +static bool mlxbf_i2c_has_chip_type(struct mlxbf_i2c_priv *priv, u8 type) +{ + return priv->chip->type == type; +} + +static struct mlxbf_i2c_resource * +mlxbf_i2c_get_shared_resource(struct mlxbf_i2c_priv *priv, u8 type) +{ + const struct mlxbf_i2c_chip_info *chip = priv->chip; + struct mlxbf_i2c_resource *res; + u8 res_idx = 0; + + for (res_idx = 0; res_idx < MLXBF_I2C_SHARED_RES_MAX; res_idx++) { + res = chip->shared_res[res_idx]; + if (res && res->type == type) + return res; + } + + return NULL; +} + +static int mlxbf_i2c_init_resource(struct platform_device *pdev, + struct mlxbf_i2c_resource **res, + u8 type) +{ + struct mlxbf_i2c_resource *tmp_res; + struct device *dev = &pdev->dev; + + if (!res || *res || type >= MLXBF_I2C_END_RES) + return -EINVAL; + + tmp_res = devm_kzalloc(dev, sizeof(struct mlxbf_i2c_resource), + GFP_KERNEL); + if (!tmp_res) + return -ENOMEM; + + tmp_res->params = platform_get_resource(pdev, IORESOURCE_MEM, type); + if (!tmp_res->params) { + devm_kfree(dev, tmp_res); + return -EIO; + } + + tmp_res->io = devm_ioremap_resource(dev, tmp_res->params); + if (IS_ERR(tmp_res->io)) { + devm_kfree(dev, tmp_res); + return PTR_ERR(tmp_res->io); + } + + tmp_res->type = type; + + *res = tmp_res; + + return 0; +} + +static u32 mlxbf_i2c_get_ticks(struct mlxbf_i2c_priv *priv, u64 nanoseconds, + bool minimum) +{ + u64 frequency; + u32 ticks; + + /* + * Compute ticks as follow: + * + * Ticks + * Time = --------- x 10^9 => Ticks = Time x Frequency x 10^-9 + * Frequency + */ + frequency = priv->frequency; + ticks = (nanoseconds * frequency) / MLXBF_I2C_FREQUENCY_1GHZ; + /* + * The number of ticks is rounded down and if minimum is equal to 1 + * then add one tick. + */ + if (minimum) + ticks++; + + return ticks; +} + +static u32 mlxbf_i2c_set_timer(struct mlxbf_i2c_priv *priv, u64 nsec, bool opt, + u32 mask, u8 shift) +{ + u32 val = (mlxbf_i2c_get_ticks(priv, nsec, opt) & mask) << shift; + + return val; +} + +static void mlxbf_i2c_set_timings(struct mlxbf_i2c_priv *priv, + const struct mlxbf_i2c_timings *timings) +{ + u32 timer; + + timer = mlxbf_i2c_set_timer(priv, timings->scl_high, + false, MLXBF_I2C_MASK_16, + MLXBF_I2C_SHIFT_0); + timer |= mlxbf_i2c_set_timer(priv, timings->scl_low, + false, MLXBF_I2C_MASK_16, + MLXBF_I2C_SHIFT_16); + writel(timer, priv->smbus->io + + MLXBF_I2C_SMBUS_TIMER_SCL_LOW_SCL_HIGH); + + timer = mlxbf_i2c_set_timer(priv, timings->sda_rise, false, + MLXBF_I2C_MASK_8, MLXBF_I2C_SHIFT_0); + timer |= mlxbf_i2c_set_timer(priv, timings->sda_fall, false, + MLXBF_I2C_MASK_8, MLXBF_I2C_SHIFT_8); + timer |= mlxbf_i2c_set_timer(priv, timings->scl_rise, false, + MLXBF_I2C_MASK_8, MLXBF_I2C_SHIFT_16); + timer |= mlxbf_i2c_set_timer(priv, timings->scl_fall, false, + MLXBF_I2C_MASK_8, MLXBF_I2C_SHIFT_24); + writel(timer, priv->smbus->io + + MLXBF_I2C_SMBUS_TIMER_FALL_RISE_SPIKE); + + timer = mlxbf_i2c_set_timer(priv, timings->hold_start, true, + MLXBF_I2C_MASK_16, MLXBF_I2C_SHIFT_0); + timer |= mlxbf_i2c_set_timer(priv, timings->hold_data, true, + MLXBF_I2C_MASK_16, MLXBF_I2C_SHIFT_16); + writel(timer, priv->smbus->io + MLXBF_I2C_SMBUS_TIMER_THOLD); + + timer = mlxbf_i2c_set_timer(priv, timings->setup_start, true, + MLXBF_I2C_MASK_16, MLXBF_I2C_SHIFT_0); + timer |= mlxbf_i2c_set_timer(priv, timings->setup_stop, true, + MLXBF_I2C_MASK_16, MLXBF_I2C_SHIFT_16); + writel(timer, priv->smbus->io + + MLXBF_I2C_SMBUS_TIMER_TSETUP_START_STOP); + + timer = mlxbf_i2c_set_timer(priv, timings->setup_data, true, + MLXBF_I2C_MASK_16, MLXBF_I2C_SHIFT_0); + writel(timer, priv->smbus->io + MLXBF_I2C_SMBUS_TIMER_TSETUP_DATA); + + timer = mlxbf_i2c_set_timer(priv, timings->buf, false, + MLXBF_I2C_MASK_16, MLXBF_I2C_SHIFT_0); + timer |= mlxbf_i2c_set_timer(priv, timings->thigh_max, false, + MLXBF_I2C_MASK_16, MLXBF_I2C_SHIFT_16); + writel(timer, priv->smbus->io + MLXBF_I2C_SMBUS_THIGH_MAX_TBUF); + + timer = timings->timeout; + writel(timer, priv->smbus->io + MLXBF_I2C_SMBUS_SCL_LOW_TIMEOUT); +} + +enum mlxbf_i2c_timings_config { + MLXBF_I2C_TIMING_CONFIG_100KHZ, + MLXBF_I2C_TIMING_CONFIG_400KHZ, + MLXBF_I2C_TIMING_CONFIG_1000KHZ, +}; + +/* + * Note that the mlxbf_i2c_timings->timeout value is not related to the + * bus frequency, it is impacted by the time it takes the driver to + * complete data transmission before transaction abort. + */ +static const struct mlxbf_i2c_timings mlxbf_i2c_timings[] = { + [MLXBF_I2C_TIMING_CONFIG_100KHZ] = { + .scl_high = 4810, + .scl_low = 5000, + .hold_start = 4000, + .setup_start = 4800, + .setup_stop = 4000, + .setup_data = 250, + .sda_rise = 50, + .sda_fall = 50, + .scl_rise = 50, + .scl_fall = 50, + .hold_data = 300, + .buf = 20000, + .thigh_max = 5000, + .timeout = 106500 + }, + [MLXBF_I2C_TIMING_CONFIG_400KHZ] = { + .scl_high = 1011, + .scl_low = 1300, + .hold_start = 600, + .setup_start = 700, + .setup_stop = 600, + .setup_data = 100, + .sda_rise = 50, + .sda_fall = 50, + .scl_rise = 50, + .scl_fall = 50, + .hold_data = 300, + .buf = 20000, + .thigh_max = 5000, + .timeout = 106500 + }, + [MLXBF_I2C_TIMING_CONFIG_1000KHZ] = { + .scl_high = 600, + .scl_low = 1300, + .hold_start = 600, + .setup_start = 600, + .setup_stop = 600, + .setup_data = 100, + .sda_rise = 50, + .sda_fall = 50, + .scl_rise = 50, + .scl_fall = 50, + .hold_data = 300, + .buf = 20000, + .thigh_max = 5000, + .timeout = 106500 + } +}; + +static int mlxbf_i2c_init_timings(struct platform_device *pdev, + struct mlxbf_i2c_priv *priv) +{ + enum mlxbf_i2c_timings_config config_idx; + struct device *dev = &pdev->dev; + u32 config_khz; + + int ret; + + ret = device_property_read_u32(dev, "clock-frequency", &config_khz); + if (ret < 0) + config_khz = MLXBF_I2C_TIMING_100KHZ; + + switch (config_khz) { + default: + /* Default settings is 100 KHz. */ + pr_warn("Illegal value %d: defaulting to 100 KHz\n", + config_khz); + fallthrough; + case MLXBF_I2C_TIMING_100KHZ: + config_idx = MLXBF_I2C_TIMING_CONFIG_100KHZ; + break; + + case MLXBF_I2C_TIMING_400KHZ: + config_idx = MLXBF_I2C_TIMING_CONFIG_400KHZ; + break; + + case MLXBF_I2C_TIMING_1000KHZ: + config_idx = MLXBF_I2C_TIMING_CONFIG_1000KHZ; + break; + } + + mlxbf_i2c_set_timings(priv, &mlxbf_i2c_timings[config_idx]); + + return 0; +} + +static int mlxbf_i2c_get_gpio(struct platform_device *pdev, + struct mlxbf_i2c_priv *priv) +{ + struct mlxbf_i2c_resource *gpio_res; + struct device *dev = &pdev->dev; + struct resource *params; + resource_size_t size; + + gpio_res = mlxbf_i2c_get_shared_resource(priv, MLXBF_I2C_GPIO_RES); + if (!gpio_res) + return -EPERM; + + /* + * The GPIO region in TYU space is shared among I2C busses. + * This function MUST be serialized to avoid racing when + * claiming the memory region and/or setting up the GPIO. + */ + lockdep_assert_held(gpio_res->lock); + + /* Check whether the memory map exist. */ + if (gpio_res->io) + return 0; + + params = gpio_res->params; + size = resource_size(params); + + if (!devm_request_mem_region(dev, params->start, size, params->name)) + return -EFAULT; + + gpio_res->io = devm_ioremap(dev, params->start, size); + if (!gpio_res->io) { + devm_release_mem_region(dev, params->start, size); + return -ENOMEM; + } + + return 0; +} + +static int mlxbf_i2c_release_gpio(struct platform_device *pdev, + struct mlxbf_i2c_priv *priv) +{ + struct mlxbf_i2c_resource *gpio_res; + struct device *dev = &pdev->dev; + struct resource *params; + + gpio_res = mlxbf_i2c_get_shared_resource(priv, MLXBF_I2C_GPIO_RES); + if (!gpio_res) + return 0; + + mutex_lock(gpio_res->lock); + + if (gpio_res->io) { + /* Release the GPIO resource. */ + params = gpio_res->params; + devm_iounmap(dev, gpio_res->io); + devm_release_mem_region(dev, params->start, + resource_size(params)); + } + + mutex_unlock(gpio_res->lock); + + return 0; +} + +static int mlxbf_i2c_get_corepll(struct platform_device *pdev, + struct mlxbf_i2c_priv *priv) +{ + struct mlxbf_i2c_resource *corepll_res; + struct device *dev = &pdev->dev; + struct resource *params; + resource_size_t size; + + corepll_res = mlxbf_i2c_get_shared_resource(priv, + MLXBF_I2C_COREPLL_RES); + if (!corepll_res) + return -EPERM; + + /* + * The COREPLL region in TYU space is shared among I2C busses. + * This function MUST be serialized to avoid racing when + * claiming the memory region. + */ + lockdep_assert_held(corepll_res->lock); + + /* Check whether the memory map exist. */ + if (corepll_res->io) + return 0; + + params = corepll_res->params; + size = resource_size(params); + + if (!devm_request_mem_region(dev, params->start, size, params->name)) + return -EFAULT; + + corepll_res->io = devm_ioremap(dev, params->start, size); + if (!corepll_res->io) { + devm_release_mem_region(dev, params->start, size); + return -ENOMEM; + } + + return 0; +} + +static int mlxbf_i2c_release_corepll(struct platform_device *pdev, + struct mlxbf_i2c_priv *priv) +{ + struct mlxbf_i2c_resource *corepll_res; + struct device *dev = &pdev->dev; + struct resource *params; + + corepll_res = mlxbf_i2c_get_shared_resource(priv, + MLXBF_I2C_COREPLL_RES); + + mutex_lock(corepll_res->lock); + + if (corepll_res->io) { + /* Release the CorePLL resource. */ + params = corepll_res->params; + devm_iounmap(dev, corepll_res->io); + devm_release_mem_region(dev, params->start, + resource_size(params)); + } + + mutex_unlock(corepll_res->lock); + + return 0; +} + +static int mlxbf_i2c_init_master(struct platform_device *pdev, + struct mlxbf_i2c_priv *priv) +{ + struct mlxbf_i2c_resource *gpio_res; + struct device *dev = &pdev->dev; + u32 config_reg; + int ret; + + /* This configuration is only needed for BlueField 1. */ + if (!mlxbf_i2c_has_chip_type(priv, MLXBF_I2C_CHIP_TYPE_1)) + return 0; + + gpio_res = mlxbf_i2c_get_shared_resource(priv, MLXBF_I2C_GPIO_RES); + if (!gpio_res) + return -EPERM; + + /* + * The GPIO region in TYU space is shared among I2C busses. + * This function MUST be serialized to avoid racing when + * claiming the memory region and/or setting up the GPIO. + */ + + mutex_lock(gpio_res->lock); + + ret = mlxbf_i2c_get_gpio(pdev, priv); + if (ret < 0) { + dev_err(dev, "Failed to get gpio resource"); + mutex_unlock(gpio_res->lock); + return ret; + } + + /* + * TYU - Configuration for GPIO pins. Those pins must be asserted in + * MLXBF_I2C_GPIO_0_FUNC_EN_0, i.e. GPIO 0 is controlled by HW, and must + * be reset in MLXBF_I2C_GPIO_0_FORCE_OE_EN, i.e. GPIO_OE will be driven + * instead of HW_OE. + * For now, we do not reset the GPIO state when the driver is removed. + * First, it is not necessary to disable the bus since we are using + * the same busses. Then, some busses might be shared among Linux and + * platform firmware; disabling the bus might compromise the system + * functionality. + */ + config_reg = readl(gpio_res->io + MLXBF_I2C_GPIO_0_FUNC_EN_0); + config_reg = MLXBF_I2C_GPIO_SMBUS_GW_ASSERT_PINS(priv->bus, + config_reg); + writel(config_reg, gpio_res->io + MLXBF_I2C_GPIO_0_FUNC_EN_0); + + config_reg = readl(gpio_res->io + MLXBF_I2C_GPIO_0_FORCE_OE_EN); + config_reg = MLXBF_I2C_GPIO_SMBUS_GW_RESET_PINS(priv->bus, + config_reg); + writel(config_reg, gpio_res->io + MLXBF_I2C_GPIO_0_FORCE_OE_EN); + + mutex_unlock(gpio_res->lock); + + return 0; +} + +static u64 mlxbf_calculate_freq_from_tyu(struct mlxbf_i2c_resource *corepll_res) +{ + u64 core_frequency, pad_frequency; + u8 core_od, core_r; + u32 corepll_val; + u16 core_f; + + pad_frequency = MLXBF_I2C_PLL_IN_FREQ; + + corepll_val = readl(corepll_res->io + MLXBF_I2C_CORE_PLL_REG1); + + /* Get Core PLL configuration bits. */ + core_f = rol32(corepll_val, MLXBF_I2C_COREPLL_CORE_F_TYU_SHIFT) & + MLXBF_I2C_COREPLL_CORE_F_TYU_MASK; + core_od = rol32(corepll_val, MLXBF_I2C_COREPLL_CORE_OD_TYU_SHIFT) & + MLXBF_I2C_COREPLL_CORE_OD_TYU_MASK; + core_r = rol32(corepll_val, MLXBF_I2C_COREPLL_CORE_R_TYU_SHIFT) & + MLXBF_I2C_COREPLL_CORE_R_TYU_MASK; + + /* + * Compute PLL output frequency as follow: + * + * CORE_F + 1 + * PLL_OUT_FREQ = PLL_IN_FREQ * ---------------------------- + * (CORE_R + 1) * (CORE_OD + 1) + * + * Where PLL_OUT_FREQ and PLL_IN_FREQ refer to CoreFrequency + * and PadFrequency, respectively. + */ + core_frequency = pad_frequency * (++core_f); + core_frequency /= (++core_r) * (++core_od); + + return core_frequency; +} + +static u64 mlxbf_calculate_freq_from_yu(struct mlxbf_i2c_resource *corepll_res) +{ + u32 corepll_reg1_val, corepll_reg2_val; + u64 corepll_frequency, pad_frequency; + u8 core_od, core_r; + u32 core_f; + + pad_frequency = MLXBF_I2C_PLL_IN_FREQ; + + corepll_reg1_val = readl(corepll_res->io + MLXBF_I2C_CORE_PLL_REG1); + corepll_reg2_val = readl(corepll_res->io + MLXBF_I2C_CORE_PLL_REG2); + + /* Get Core PLL configuration bits */ + core_f = rol32(corepll_reg1_val, MLXBF_I2C_COREPLL_CORE_F_YU_SHIFT) & + MLXBF_I2C_COREPLL_CORE_F_YU_MASK; + core_r = rol32(corepll_reg1_val, MLXBF_I2C_COREPLL_CORE_R_YU_SHIFT) & + MLXBF_I2C_COREPLL_CORE_R_YU_MASK; + core_od = rol32(corepll_reg2_val, MLXBF_I2C_COREPLL_CORE_OD_YU_SHIFT) & + MLXBF_I2C_COREPLL_CORE_OD_YU_MASK; + + /* + * Compute PLL output frequency as follow: + * + * CORE_F / 16384 + * PLL_OUT_FREQ = PLL_IN_FREQ * ---------------------------- + * (CORE_R + 1) * (CORE_OD + 1) + * + * Where PLL_OUT_FREQ and PLL_IN_FREQ refer to CoreFrequency + * and PadFrequency, respectively. + */ + corepll_frequency = (pad_frequency * core_f) / MLNXBF_I2C_COREPLL_CONST; + corepll_frequency /= (++core_r) * (++core_od); + + return corepll_frequency; +} + +static int mlxbf_i2c_calculate_corepll_freq(struct platform_device *pdev, + struct mlxbf_i2c_priv *priv) +{ + const struct mlxbf_i2c_chip_info *chip = priv->chip; + struct mlxbf_i2c_resource *corepll_res; + struct device *dev = &pdev->dev; + u64 *freq = &priv->frequency; + int ret; + + corepll_res = mlxbf_i2c_get_shared_resource(priv, + MLXBF_I2C_COREPLL_RES); + if (!corepll_res) + return -EPERM; + + /* + * First, check whether the TYU core Clock frequency is set. + * The TYU core frequency is the same for all I2C busses; when + * the first device gets probed the frequency is determined and + * stored into a globally visible variable. So, first of all, + * check whether the frequency is already set. Here, we assume + * that the frequency is expected to be greater than 0. + */ + mutex_lock(corepll_res->lock); + if (!mlxbf_i2c_corepll_frequency) { + if (!chip->calculate_freq) { + mutex_unlock(corepll_res->lock); + return -EPERM; + } + + ret = mlxbf_i2c_get_corepll(pdev, priv); + if (ret < 0) { + dev_err(dev, "Failed to get corePLL resource"); + mutex_unlock(corepll_res->lock); + return ret; + } + + mlxbf_i2c_corepll_frequency = chip->calculate_freq(corepll_res); + } + mutex_unlock(corepll_res->lock); + + *freq = mlxbf_i2c_corepll_frequency; + + return 0; +} + +static int mlxbf_slave_enable(struct mlxbf_i2c_priv *priv, + struct i2c_client *slave) +{ + u32 slave_reg, slave_reg_tmp, slave_addr_mask; + u8 reg, reg_cnt, byte, addr_tmp; + + if (!priv) + return -EPERM; + + reg_cnt = MLXBF_I2C_SMBUS_SLAVE_ADDR_CNT >> 2; + slave_addr_mask = MLXBF_I2C_SMBUS_SLAVE_ADDR_MASK; + + /* + * Read the slave registers. There are 4 * 32-bit slave registers. + * Each slave register can hold up to 4 * 8-bit slave configuration: + * 1) A 7-bit address + * 2) And a status bit (1 if enabled, 0 if not). + * Look for the next available slave register slot. + */ + for (reg = 0; reg < reg_cnt; reg++) { + slave_reg = readl(priv->smbus->io + + MLXBF_I2C_SMBUS_SLAVE_ADDR_CFG + reg * 0x4); + /* + * Each register holds 4 slave addresses. So, we have to keep + * the byte order consistent with the value read in order to + * update the register correctly, if needed. + */ + slave_reg_tmp = slave_reg; + for (byte = 0; byte < 4; byte++) { + addr_tmp = slave_reg_tmp & GENMASK(7, 0); + + /* + * If an enable bit is not set in the + * MLXBF_I2C_SMBUS_SLAVE_ADDR_CFG register, then the + * slave address slot associated with that bit is + * free. So set the enable bit and write the + * slave address bits. + */ + if (!MLXBF_I2C_SLAVE_ADDR_ENABLED(addr_tmp)) { + slave_reg &= ~(slave_addr_mask << (byte * 8)); + slave_reg |= (slave->addr << (byte * 8)); + slave_reg |= ((1 << + MLXBF_I2C_SMBUS_SLAVE_ADDR_EN_BIT) + << (byte * 8)); + writel(slave_reg, priv->smbus->io + + MLXBF_I2C_SMBUS_SLAVE_ADDR_CFG + + (reg * 0x4)); + + /* + * Set the slave at the corresponding index. + */ + priv->slave[(reg * 4) + byte] = slave; + + return 0; + } + + /* Parse next byte. */ + slave_reg_tmp >>= 8; + } + } + + return -EBUSY; +} + +static int mlxbf_slave_disable(struct mlxbf_i2c_priv *priv, u8 addr) +{ + u32 slave_reg, slave_reg_tmp, slave_addr_mask; + u8 addr_tmp, reg, reg_cnt, byte; + + reg_cnt = MLXBF_I2C_SMBUS_SLAVE_ADDR_CNT >> 2; + slave_addr_mask = MLXBF_I2C_SMBUS_SLAVE_ADDR_MASK; + + /* + * Read the slave registers. There are 4 * 32-bit slave registers. + * Each slave register can hold up to 4 * 8-bit slave configuration: + * 1) A 7-bit address + * 2) And a status bit (1 if enabled, 0 if not). + * Check if addr is present in the registers. + */ + for (reg = 0; reg < reg_cnt; reg++) { + slave_reg = readl(priv->smbus->io + + MLXBF_I2C_SMBUS_SLAVE_ADDR_CFG + (reg * 0x4)); + + /* Check whether the address slots are empty. */ + if (!slave_reg) + continue; + + /* + * Check if addr matches any of the 4 slave addresses + * in the register. + */ + slave_reg_tmp = slave_reg; + for (byte = 0; byte < 4; byte++) { + addr_tmp = slave_reg_tmp & slave_addr_mask; + /* + * Parse slave address bytes and check whether the + * slave address already exists. + */ + if (addr_tmp == addr) { + /* Clear the slave address slot. */ + slave_reg &= ~(GENMASK(7, 0) << (byte * 8)); + writel(slave_reg, priv->smbus->io + + MLXBF_I2C_SMBUS_SLAVE_ADDR_CFG + + (reg * 0x4)); + /* Free slave at the corresponding index */ + priv->slave[(reg * 4) + byte] = NULL; + + return 0; + } + + /* Parse next byte. */ + slave_reg_tmp >>= 8; + } + } + + return -ENXIO; +} + +static int mlxbf_i2c_init_coalesce(struct platform_device *pdev, + struct mlxbf_i2c_priv *priv) +{ + struct mlxbf_i2c_resource *coalesce_res; + struct resource *params; + resource_size_t size; + int ret = 0; + + /* + * Unlike BlueField-1 platform, the coalesce registers is a dedicated + * resource in the next generations of BlueField. + */ + if (mlxbf_i2c_has_chip_type(priv, MLXBF_I2C_CHIP_TYPE_1)) { + coalesce_res = mlxbf_i2c_get_shared_resource(priv, + MLXBF_I2C_COALESCE_RES); + if (!coalesce_res) + return -EPERM; + + /* + * The Cause Coalesce group in TYU space is shared among + * I2C busses. This function MUST be serialized to avoid + * racing when claiming the memory region. + */ + lockdep_assert_held(mlxbf_i2c_gpio_res->lock); + + /* Check whether the memory map exist. */ + if (coalesce_res->io) { + priv->coalesce = coalesce_res; + return 0; + } + + params = coalesce_res->params; + size = resource_size(params); + + if (!request_mem_region(params->start, size, params->name)) + return -EFAULT; + + coalesce_res->io = ioremap(params->start, size); + if (!coalesce_res->io) { + release_mem_region(params->start, size); + return -ENOMEM; + } + + priv->coalesce = coalesce_res; + + } else { + ret = mlxbf_i2c_init_resource(pdev, &priv->coalesce, + MLXBF_I2C_COALESCE_RES); + } + + return ret; +} + +static int mlxbf_i2c_release_coalesce(struct platform_device *pdev, + struct mlxbf_i2c_priv *priv) +{ + struct mlxbf_i2c_resource *coalesce_res; + struct device *dev = &pdev->dev; + struct resource *params; + resource_size_t size; + + coalesce_res = priv->coalesce; + + if (coalesce_res->io) { + params = coalesce_res->params; + size = resource_size(params); + if (mlxbf_i2c_has_chip_type(priv, MLXBF_I2C_CHIP_TYPE_1)) { + mutex_lock(coalesce_res->lock); + iounmap(coalesce_res->io); + release_mem_region(params->start, size); + mutex_unlock(coalesce_res->lock); + } else { + devm_release_mem_region(dev, params->start, size); + } + } + + return 0; +} + +static int mlxbf_i2c_init_slave(struct platform_device *pdev, + struct mlxbf_i2c_priv *priv) +{ + struct device *dev = &pdev->dev; + u32 int_reg; + int ret; + + /* Reset FSM. */ + writel(0, priv->smbus->io + MLXBF_I2C_SMBUS_SLAVE_FSM); + + /* + * Enable slave cause interrupt bits. Drive + * MLXBF_I2C_CAUSE_READ_WAIT_FW_RESPONSE and + * MLXBF_I2C_CAUSE_WRITE_SUCCESS, these are enabled when an external + * masters issue a Read and Write, respectively. But, clear all + * interrupts first. + */ + writel(~0, priv->slv_cause->io + MLXBF_I2C_CAUSE_OR_CLEAR); + int_reg = MLXBF_I2C_CAUSE_READ_WAIT_FW_RESPONSE; + int_reg |= MLXBF_I2C_CAUSE_WRITE_SUCCESS; + writel(int_reg, priv->slv_cause->io + MLXBF_I2C_CAUSE_OR_EVTEN0); + + /* Finally, set the 'ready' bit to start handling transactions. */ + writel(0x1, priv->smbus->io + MLXBF_I2C_SMBUS_SLAVE_READY); + + /* Initialize the cause coalesce resource. */ + ret = mlxbf_i2c_init_coalesce(pdev, priv); + if (ret < 0) { + dev_err(dev, "failed to initialize cause coalesce\n"); + return ret; + } + + return 0; +} + +static bool mlxbf_i2c_has_coalesce(struct mlxbf_i2c_priv *priv, bool *read, + bool *write) +{ + const struct mlxbf_i2c_chip_info *chip = priv->chip; + u32 coalesce0_reg, cause_reg; + u8 slave_shift, is_set; + + *write = false; + *read = false; + + slave_shift = chip->type != MLXBF_I2C_CHIP_TYPE_1 ? + MLXBF_I2C_CAUSE_YU_SLAVE_BIT : + priv->bus + MLXBF_I2C_CAUSE_TYU_SLAVE_BIT; + + coalesce0_reg = readl(priv->coalesce->io + MLXBF_I2C_CAUSE_COALESCE_0); + is_set = coalesce0_reg & (1 << slave_shift); + + if (!is_set) + return false; + + /* Check the source of the interrupt, i.e. whether a Read or Write. */ + cause_reg = readl(priv->slv_cause->io + MLXBF_I2C_CAUSE_ARBITER); + if (cause_reg & MLXBF_I2C_CAUSE_READ_WAIT_FW_RESPONSE) + *read = true; + else if (cause_reg & MLXBF_I2C_CAUSE_WRITE_SUCCESS) + *write = true; + + /* Clear cause bits. */ + writel(~0x0, priv->slv_cause->io + MLXBF_I2C_CAUSE_OR_CLEAR); + + return true; +} + +static bool mlxbf_smbus_slave_wait_for_idle(struct mlxbf_i2c_priv *priv, + u32 timeout) +{ + u32 mask = MLXBF_I2C_CAUSE_S_GW_BUSY_FALL; + u32 addr = MLXBF_I2C_CAUSE_ARBITER; + + if (mlxbf_smbus_poll(priv->slv_cause->io, addr, mask, false, timeout)) + return true; + + return false; +} + +static struct i2c_client *mlxbf_smbus_get_slave_from_addr( + struct mlxbf_i2c_priv *priv, u8 addr) +{ + int i; + + for (i = 0; i < MLXBF_I2C_SMBUS_SLAVE_ADDR_CNT; i++) { + if (!priv->slave[i]) + continue; + + if (priv->slave[i]->addr == addr) + return priv->slave[i]; + } + + return NULL; +} + +/* + * Send byte to 'external' smbus master. This function is executed when + * an external smbus master wants to read data from the BlueField. + */ +static int mlxbf_smbus_irq_send(struct mlxbf_i2c_priv *priv, u8 recv_bytes) +{ + u8 write_size, pec_en, addr, value, byte_cnt, desc_size; + u8 data_desc[MLXBF_I2C_SLAVE_DATA_DESC_SIZE] = { 0 }; + struct i2c_client *slave; + u32 control32, data32; + int ret = 0; + + desc_size = MLXBF_I2C_SLAVE_DATA_DESC_SIZE; + + /* + * Read the first byte received from the external master to + * determine the slave address. This byte is located in the + * first data descriptor register of the slave GW. + */ + data32 = ioread32be(priv->smbus->io + + MLXBF_I2C_SLAVE_DATA_DESC_ADDR); + addr = (data32 & GENMASK(7, 0)) >> 1; + + /* + * Check if the slave address received in the data descriptor register + * matches any of the slave addresses registered. If there is a match, + * set the slave. + */ + slave = mlxbf_smbus_get_slave_from_addr(priv, addr); + if (!slave) { + ret = -ENXIO; + goto clear_csr; + } + + /* + * An I2C read can consist of a WRITE bit transaction followed by + * a READ bit transaction. Indeed, slave devices often expect + * the slave address to be followed by the internal address. + * So, write the internal address byte first, and then, send the + * requested data to the master. + */ + if (recv_bytes > 1) { + i2c_slave_event(slave, I2C_SLAVE_WRITE_REQUESTED, &value); + value = (data32 >> 8) & GENMASK(7, 0); + ret = i2c_slave_event(slave, I2C_SLAVE_WRITE_RECEIVED, + &value); + i2c_slave_event(slave, I2C_SLAVE_STOP, &value); + + if (ret < 0) + goto clear_csr; + } + + /* + * Send data to the master. Currently, the driver supports + * READ_BYTE, READ_WORD and BLOCK READ protocols. The + * hardware can send up to 128 bytes per transfer which is + * the total size of the data registers. + */ + i2c_slave_event(slave, I2C_SLAVE_READ_REQUESTED, &value); + + for (byte_cnt = 0; byte_cnt < desc_size; byte_cnt++) { + data_desc[byte_cnt] = value; + i2c_slave_event(slave, I2C_SLAVE_READ_PROCESSED, &value); + } + + /* Send a stop condition to the backend. */ + i2c_slave_event(slave, I2C_SLAVE_STOP, &value); + + /* Set the number of bytes to write to master. */ + write_size = (byte_cnt - 1) & 0x7f; + + /* Write data to Slave GW data descriptor. */ + mlxbf_i2c_smbus_write_data(priv, data_desc, byte_cnt, + MLXBF_I2C_SLAVE_DATA_DESC_ADDR); + + pec_en = 0; /* Disable PEC since it is not supported. */ + + /* Prepare control word. */ + control32 = MLXBF_I2C_SLAVE_ENABLE; + control32 |= rol32(write_size, MLXBF_I2C_SLAVE_WRITE_BYTES_SHIFT); + control32 |= rol32(pec_en, MLXBF_I2C_SLAVE_SEND_PEC_SHIFT); + + writel(control32, priv->smbus->io + MLXBF_I2C_SMBUS_SLAVE_GW); + + /* + * Wait until the transfer is completed; the driver will wait + * until the GW is idle, a cause will rise on fall of GW busy. + */ + mlxbf_smbus_slave_wait_for_idle(priv, MLXBF_I2C_SMBUS_TIMEOUT); + +clear_csr: + /* Release the Slave GW. */ + writel(0x0, priv->smbus->io + MLXBF_I2C_SMBUS_SLAVE_RS_MASTER_BYTES); + writel(0x0, priv->smbus->io + MLXBF_I2C_SMBUS_SLAVE_PEC); + writel(0x1, priv->smbus->io + MLXBF_I2C_SMBUS_SLAVE_READY); + + return ret; +} + +/* + * Receive bytes from 'external' smbus master. This function is executed when + * an external smbus master wants to write data to the BlueField. + */ +static int mlxbf_smbus_irq_recv(struct mlxbf_i2c_priv *priv, u8 recv_bytes) +{ + u8 data_desc[MLXBF_I2C_SLAVE_DATA_DESC_SIZE] = { 0 }; + struct i2c_client *slave; + u8 value, byte, addr; + int ret = 0; + + /* Read data from Slave GW data descriptor. */ + mlxbf_i2c_smbus_read_data(priv, data_desc, recv_bytes, + MLXBF_I2C_SLAVE_DATA_DESC_ADDR); + addr = data_desc[0] >> 1; + + /* + * Check if the slave address received in the data descriptor register + * matches any of the slave addresses registered. + */ + slave = mlxbf_smbus_get_slave_from_addr(priv, addr); + if (!slave) { + ret = -EINVAL; + goto clear_csr; + } + + /* + * Notify the slave backend that an smbus master wants to write data + * to the BlueField. + */ + i2c_slave_event(slave, I2C_SLAVE_WRITE_REQUESTED, &value); + + /* Send the received data to the slave backend. */ + for (byte = 1; byte < recv_bytes; byte++) { + value = data_desc[byte]; + ret = i2c_slave_event(slave, I2C_SLAVE_WRITE_RECEIVED, + &value); + if (ret < 0) + break; + } + + /* + * Send a stop event to the slave backend, to signal + * the end of the write transactions. + */ + i2c_slave_event(slave, I2C_SLAVE_STOP, &value); + +clear_csr: + /* Release the Slave GW. */ + writel(0x0, priv->smbus->io + MLXBF_I2C_SMBUS_SLAVE_RS_MASTER_BYTES); + writel(0x0, priv->smbus->io + MLXBF_I2C_SMBUS_SLAVE_PEC); + writel(0x1, priv->smbus->io + MLXBF_I2C_SMBUS_SLAVE_READY); + + return ret; +} + +static irqreturn_t mlxbf_smbus_irq(int irq, void *ptr) +{ + struct mlxbf_i2c_priv *priv = ptr; + bool read, write, irq_is_set; + u32 rw_bytes_reg; + u8 recv_bytes; + + /* + * Read TYU interrupt register and determine the source of the + * interrupt. Based on the source of the interrupt one of the + * following actions are performed: + * - Receive data and send response to master. + * - Send data and release slave GW. + * + * Handle read/write transaction only. CRmaster and Iarp requests + * are ignored for now. + */ + irq_is_set = mlxbf_i2c_has_coalesce(priv, &read, &write); + if (!irq_is_set || (!read && !write)) { + /* Nothing to do here, interrupt was not from this device. */ + return IRQ_NONE; + } + + /* + * The MLXBF_I2C_SMBUS_SLAVE_RS_MASTER_BYTES includes the number of + * bytes from/to master. These are defined by 8-bits each. If the lower + * 8 bits are set, then the master expect to read N bytes from the + * slave, if the higher 8 bits are sent then the slave expect N bytes + * from the master. + */ + rw_bytes_reg = readl(priv->smbus->io + + MLXBF_I2C_SMBUS_SLAVE_RS_MASTER_BYTES); + recv_bytes = (rw_bytes_reg >> 8) & GENMASK(7, 0); + + /* + * For now, the slave supports 128 bytes transfer. Discard remaining + * data bytes if the master wrote more than + * MLXBF_I2C_SLAVE_DATA_DESC_SIZE, i.e, the actual size of the slave + * data descriptor. + * + * Note that we will never expect to transfer more than 128 bytes; as + * specified in the SMBus standard, block transactions cannot exceed + * 32 bytes. + */ + recv_bytes = recv_bytes > MLXBF_I2C_SLAVE_DATA_DESC_SIZE ? + MLXBF_I2C_SLAVE_DATA_DESC_SIZE : recv_bytes; + + if (read) + mlxbf_smbus_irq_send(priv, recv_bytes); + else + mlxbf_smbus_irq_recv(priv, recv_bytes); + + return IRQ_HANDLED; +} + +/* Return negative errno on error. */ +static s32 mlxbf_i2c_smbus_xfer(struct i2c_adapter *adap, u16 addr, + unsigned short flags, char read_write, + u8 command, int size, + union i2c_smbus_data *data) +{ + struct mlxbf_i2c_smbus_request request = { 0 }; + struct mlxbf_i2c_priv *priv; + bool read, pec; + u8 byte_cnt; + + request.slave = addr; + + read = (read_write == I2C_SMBUS_READ); + pec = flags & I2C_FUNC_SMBUS_PEC; + + switch (size) { + case I2C_SMBUS_QUICK: + mlxbf_i2c_smbus_quick_command(&request, read); + dev_dbg(&adap->dev, "smbus quick, slave 0x%02x\n", addr); + break; + + case I2C_SMBUS_BYTE: + mlxbf_i2c_smbus_byte_func(&request, + read ? &data->byte : &command, read, + pec); + dev_dbg(&adap->dev, "smbus %s byte, slave 0x%02x.\n", + read ? "read" : "write", addr); + break; + + case I2C_SMBUS_BYTE_DATA: + mlxbf_i2c_smbus_data_byte_func(&request, &command, &data->byte, + read, pec); + dev_dbg(&adap->dev, "smbus %s byte data at 0x%02x, slave 0x%02x.\n", + read ? "read" : "write", command, addr); + break; + + case I2C_SMBUS_WORD_DATA: + mlxbf_i2c_smbus_data_word_func(&request, &command, + (u8 *)&data->word, read, pec); + dev_dbg(&adap->dev, "smbus %s word data at 0x%02x, slave 0x%02x.\n", + read ? "read" : "write", command, addr); + break; + + case I2C_SMBUS_I2C_BLOCK_DATA: + byte_cnt = data->block[0]; + mlxbf_i2c_smbus_i2c_block_func(&request, &command, data->block, + &byte_cnt, read, pec); + dev_dbg(&adap->dev, "i2c %s block data, %d bytes at 0x%02x, slave 0x%02x.\n", + read ? "read" : "write", byte_cnt, command, addr); + break; + + case I2C_SMBUS_BLOCK_DATA: + byte_cnt = read ? I2C_SMBUS_BLOCK_MAX : data->block[0]; + mlxbf_i2c_smbus_block_func(&request, &command, data->block, + &byte_cnt, read, pec); + dev_dbg(&adap->dev, "smbus %s block data, %d bytes at 0x%02x, slave 0x%02x.\n", + read ? "read" : "write", byte_cnt, command, addr); + break; + + case I2C_FUNC_SMBUS_PROC_CALL: + mlxbf_i2c_smbus_process_call_func(&request, &command, + (u8 *)&data->word, pec); + dev_dbg(&adap->dev, "process call, wr/rd at 0x%02x, slave 0x%02x.\n", + command, addr); + break; + + case I2C_FUNC_SMBUS_BLOCK_PROC_CALL: + byte_cnt = data->block[0]; + mlxbf_i2c_smbus_blk_process_call_func(&request, &command, + data->block, &byte_cnt, + pec); + dev_dbg(&adap->dev, "block process call, wr/rd %d bytes, slave 0x%02x.\n", + byte_cnt, addr); + break; + + default: + dev_dbg(&adap->dev, "Unsupported I2C/SMBus command %d\n", + size); + return -EOPNOTSUPP; + } + + priv = i2c_get_adapdata(adap); + + return mlxbf_i2c_smbus_start_transaction(priv, &request); +} + +static int mlxbf_i2c_reg_slave(struct i2c_client *slave) +{ + struct mlxbf_i2c_priv *priv = i2c_get_adapdata(slave->adapter); + struct device *dev = &slave->dev; + int ret; + + /* + * Do not support ten bit chip address and do not use Packet Error + * Checking (PEC). + */ + if (slave->flags & (I2C_CLIENT_TEN | I2C_CLIENT_PEC)) { + dev_err(dev, "SMBus PEC and 10 bit address not supported\n"); + return -EAFNOSUPPORT; + } + + ret = mlxbf_slave_enable(priv, slave); + if (ret) + dev_err(dev, "Surpassed max number of registered slaves allowed\n"); + + return 0; +} + +static int mlxbf_i2c_unreg_slave(struct i2c_client *slave) +{ + struct mlxbf_i2c_priv *priv = i2c_get_adapdata(slave->adapter); + struct device *dev = &slave->dev; + int ret; + + /* + * Unregister slave by: + * 1) Disabling the slave address in hardware + * 2) Freeing priv->slave at the corresponding index + */ + ret = mlxbf_slave_disable(priv, slave->addr); + if (ret) + dev_err(dev, "Unable to find slave 0x%x\n", slave->addr); + + return ret; +} + +static u32 mlxbf_i2c_functionality(struct i2c_adapter *adap) +{ + return MLXBF_I2C_FUNC_ALL; +} + +static struct mlxbf_i2c_chip_info mlxbf_i2c_chip[] = { + [MLXBF_I2C_CHIP_TYPE_1] = { + .type = MLXBF_I2C_CHIP_TYPE_1, + .shared_res = { + [0] = &mlxbf_i2c_coalesce_res[MLXBF_I2C_CHIP_TYPE_1], + [1] = &mlxbf_i2c_corepll_res[MLXBF_I2C_CHIP_TYPE_1], + [2] = &mlxbf_i2c_gpio_res[MLXBF_I2C_CHIP_TYPE_1] + }, + .calculate_freq = mlxbf_calculate_freq_from_tyu + }, + [MLXBF_I2C_CHIP_TYPE_2] = { + .type = MLXBF_I2C_CHIP_TYPE_2, + .shared_res = { + [0] = &mlxbf_i2c_corepll_res[MLXBF_I2C_CHIP_TYPE_2] + }, + .calculate_freq = mlxbf_calculate_freq_from_yu + } +}; + +static const struct i2c_algorithm mlxbf_i2c_algo = { + .smbus_xfer = mlxbf_i2c_smbus_xfer, + .functionality = mlxbf_i2c_functionality, + .reg_slave = mlxbf_i2c_reg_slave, + .unreg_slave = mlxbf_i2c_unreg_slave, +}; + +static struct i2c_adapter_quirks mlxbf_i2c_quirks = { + .max_read_len = MLXBF_I2C_MASTER_DATA_R_LENGTH, + .max_write_len = MLXBF_I2C_MASTER_DATA_W_LENGTH, +}; + +static const struct of_device_id mlxbf_i2c_dt_ids[] = { + { + .compatible = "mellanox,i2c-mlxbf1", + .data = &mlxbf_i2c_chip[MLXBF_I2C_CHIP_TYPE_1] + }, + { + .compatible = "mellanox,i2c-mlxbf2", + .data = &mlxbf_i2c_chip[MLXBF_I2C_CHIP_TYPE_2] + }, + {}, +}; + +MODULE_DEVICE_TABLE(of, mlxbf_i2c_dt_ids); + +#ifdef CONFIG_ACPI +static const struct acpi_device_id mlxbf_i2c_acpi_ids[] = { + { "MLNXBF03", (kernel_ulong_t)&mlxbf_i2c_chip[MLXBF_I2C_CHIP_TYPE_1] }, + { "MLNXBF23", (kernel_ulong_t)&mlxbf_i2c_chip[MLXBF_I2C_CHIP_TYPE_2] }, + {}, +}; + +MODULE_DEVICE_TABLE(acpi, mlxbf_i2c_acpi_ids); + +static int mlxbf_i2c_acpi_probe(struct device *dev, struct mlxbf_i2c_priv *priv) +{ + const struct acpi_device_id *aid; + struct acpi_device *adev; + unsigned long bus_id = 0; + const char *uid; + int ret; + + if (acpi_disabled) + return -ENOENT; + + adev = ACPI_COMPANION(dev); + if (!adev) + return -ENXIO; + + aid = acpi_match_device(mlxbf_i2c_acpi_ids, dev); + if (!aid) + return -ENODEV; + + priv->chip = (struct mlxbf_i2c_chip_info *)aid->driver_data; + + uid = acpi_device_uid(adev); + if (!uid || !(*uid)) { + dev_err(dev, "Cannot retrieve UID\n"); + return -ENODEV; + } + + ret = kstrtoul(uid, 0, &bus_id); + if (!ret) + priv->bus = bus_id; + + return ret; +} +#else +static int mlxbf_i2c_acpi_probe(struct device *dev, struct mlxbf_i2c_priv *priv) +{ + return -ENOENT; +} +#endif /* CONFIG_ACPI */ + +static int mlxbf_i2c_of_probe(struct device *dev, struct mlxbf_i2c_priv *priv) +{ + const struct of_device_id *oid; + int bus_id = -1; + + if (IS_ENABLED(CONFIG_OF) && dev->of_node) { + oid = of_match_node(mlxbf_i2c_dt_ids, dev->of_node); + if (!oid) + return -ENODEV; + + priv->chip = oid->data; + + bus_id = of_alias_get_id(dev->of_node, "i2c"); + if (bus_id >= 0) + priv->bus = bus_id; + } + + if (bus_id < 0) { + dev_err(dev, "Cannot get bus id"); + return bus_id; + } + + return 0; +} + +static int mlxbf_i2c_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct mlxbf_i2c_priv *priv; + struct i2c_adapter *adap; + int irq, ret; + + priv = devm_kzalloc(dev, sizeof(struct mlxbf_i2c_priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + ret = mlxbf_i2c_acpi_probe(dev, priv); + if (ret < 0 && ret != -ENOENT && ret != -ENXIO) + ret = mlxbf_i2c_of_probe(dev, priv); + + if (ret < 0) + return ret; + + ret = mlxbf_i2c_init_resource(pdev, &priv->smbus, + MLXBF_I2C_SMBUS_RES); + if (ret < 0) { + dev_err(dev, "Cannot fetch smbus resource info"); + return ret; + } + + ret = mlxbf_i2c_init_resource(pdev, &priv->mst_cause, + MLXBF_I2C_MST_CAUSE_RES); + if (ret < 0) { + dev_err(dev, "Cannot fetch cause master resource info"); + return ret; + } + + ret = mlxbf_i2c_init_resource(pdev, &priv->slv_cause, + MLXBF_I2C_SLV_CAUSE_RES); + if (ret < 0) { + dev_err(dev, "Cannot fetch cause slave resource info"); + return ret; + } + + adap = &priv->adap; + adap->owner = THIS_MODULE; + adap->class = I2C_CLASS_HWMON; + adap->algo = &mlxbf_i2c_algo; + adap->quirks = &mlxbf_i2c_quirks; + adap->dev.parent = dev; + adap->dev.of_node = dev->of_node; + adap->nr = priv->bus; + + snprintf(adap->name, sizeof(adap->name), "i2c%d", adap->nr); + i2c_set_adapdata(adap, priv); + + /* Read Core PLL frequency. */ + ret = mlxbf_i2c_calculate_corepll_freq(pdev, priv); + if (ret < 0) { + dev_err(dev, "cannot get core clock frequency\n"); + /* Set to default value. */ + priv->frequency = MLXBF_I2C_COREPLL_FREQ; + } + + /* + * Initialize master. + * Note that a physical bus might be shared among Linux and firmware + * (e.g., ATF). Thus, the bus should be initialized and ready and + * bus initialization would be unnecessary. This requires additional + * knowledge about physical busses. But, since an extra initialization + * does not really hurt, then keep the code as is. + */ + ret = mlxbf_i2c_init_master(pdev, priv); + if (ret < 0) { + dev_err(dev, "failed to initialize smbus master %d", + priv->bus); + return ret; + } + + mlxbf_i2c_init_timings(pdev, priv); + + mlxbf_i2c_init_slave(pdev, priv); + + irq = platform_get_irq(pdev, 0); + ret = devm_request_irq(dev, irq, mlxbf_smbus_irq, + IRQF_ONESHOT | IRQF_SHARED | IRQF_PROBE_SHARED, + dev_name(dev), priv); + if (ret < 0) { + dev_err(dev, "Cannot get irq %d\n", irq); + return ret; + } + + priv->irq = irq; + + platform_set_drvdata(pdev, priv); + + ret = i2c_add_numbered_adapter(adap); + if (ret < 0) + return ret; + + mutex_lock(&mlxbf_i2c_bus_lock); + mlxbf_i2c_bus_count++; + mutex_unlock(&mlxbf_i2c_bus_lock); + + return 0; +} + +static int mlxbf_i2c_remove(struct platform_device *pdev) +{ + struct mlxbf_i2c_priv *priv = platform_get_drvdata(pdev); + struct device *dev = &pdev->dev; + struct resource *params; + + params = priv->smbus->params; + devm_release_mem_region(dev, params->start, resource_size(params)); + + params = priv->mst_cause->params; + devm_release_mem_region(dev, params->start, resource_size(params)); + + params = priv->slv_cause->params; + devm_release_mem_region(dev, params->start, resource_size(params)); + + /* + * Release shared resources. This should be done when releasing + * the I2C controller. + */ + mutex_lock(&mlxbf_i2c_bus_lock); + if (--mlxbf_i2c_bus_count == 0) { + mlxbf_i2c_release_coalesce(pdev, priv); + mlxbf_i2c_release_corepll(pdev, priv); + mlxbf_i2c_release_gpio(pdev, priv); + } + mutex_unlock(&mlxbf_i2c_bus_lock); + + i2c_del_adapter(&priv->adap); + + return 0; +} + +static struct platform_driver mlxbf_i2c_driver = { + .probe = mlxbf_i2c_probe, + .remove = mlxbf_i2c_remove, + .driver = { + .name = "i2c-mlxbf", + .of_match_table = mlxbf_i2c_dt_ids, +#ifdef CONFIG_ACPI + .acpi_match_table = ACPI_PTR(mlxbf_i2c_acpi_ids), +#endif /* CONFIG_ACPI */ + }, +}; + +static int __init mlxbf_i2c_init(void) +{ + mutex_init(&mlxbf_i2c_coalesce_lock); + mutex_init(&mlxbf_i2c_corepll_lock); + mutex_init(&mlxbf_i2c_gpio_lock); + + mutex_init(&mlxbf_i2c_bus_lock); + + return platform_driver_register(&mlxbf_i2c_driver); +} +module_init(mlxbf_i2c_init); + +static void __exit mlxbf_i2c_exit(void) +{ + platform_driver_unregister(&mlxbf_i2c_driver); + + mutex_destroy(&mlxbf_i2c_bus_lock); + + mutex_destroy(&mlxbf_i2c_gpio_lock); + mutex_destroy(&mlxbf_i2c_corepll_lock); + mutex_destroy(&mlxbf_i2c_coalesce_lock); +} +module_exit(mlxbf_i2c_exit); + +MODULE_DESCRIPTION("Mellanox BlueField I2C bus driver"); +MODULE_AUTHOR("Khalil Blaiech "); +MODULE_LICENSE("GPL v2");