From patchwork Thu Dec 13 11:41:23 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vipin Kumar X-Patchwork-Id: 205814 X-Patchwork-Delegate: jagannadh.teki@gmail.com Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from theia.denx.de (theia.denx.de [85.214.87.163]) by ozlabs.org (Postfix) with ESMTP id B3B1D2C008E for ; Thu, 13 Dec 2012 22:41:47 +1100 (EST) Received: from localhost (localhost [127.0.0.1]) by theia.denx.de (Postfix) with ESMTP id 566D74A159; Thu, 13 Dec 2012 12:41:46 +0100 (CET) X-Virus-Scanned: Debian amavisd-new at theia.denx.de Received: from theia.denx.de ([127.0.0.1]) by localhost (theia.denx.de [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id h6D+zRhn+3+Z; Thu, 13 Dec 2012 12:41:46 +0100 (CET) Received: from theia.denx.de (localhost [127.0.0.1]) by theia.denx.de (Postfix) with ESMTP id 88BEC4A15D; Thu, 13 Dec 2012 12:41:44 +0100 (CET) Received: from localhost (localhost [127.0.0.1]) by theia.denx.de (Postfix) with ESMTP id C46564A15D for ; Thu, 13 Dec 2012 12:41:41 +0100 (CET) X-Virus-Scanned: Debian amavisd-new at theia.denx.de Received: from theia.denx.de ([127.0.0.1]) by localhost (theia.denx.de [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id v-HmYd-lIaNs for ; Thu, 13 Dec 2012 12:41:40 +0100 (CET) X-policyd-weight: NOT_IN_SBL_XBL_SPAMHAUS=-1.5 NOT_IN_SPAMCOP=-1.5 NOT_IN_BL_NJABL=-1.5 (only DNSBL check requested) Received: from eu1sys200aog113.obsmtp.com (eu1sys200aog113.obsmtp.com [207.126.144.135]) by theia.denx.de (Postfix) with ESMTPS id F35694A159 for ; Thu, 13 Dec 2012 12:41:37 +0100 (CET) Received: from beta.dmz-ap.st.com ([138.198.100.35]) (using TLSv1) by eu1sys200aob113.postini.com ([207.126.147.11]) with SMTP ID DSNKUMm+71f741YHDI+CkMAoOt0tTBRnllrH@postini.com; Thu, 13 Dec 2012 11:41:39 UTC Received: from zeta.dmz-ap.st.com (ns6.st.com [138.198.234.13]) by beta.dmz-ap.st.com (STMicroelectronics) with ESMTP id 48532155; Thu, 13 Dec 2012 11:33:19 +0000 (GMT) Received: from Webmail-ap.st.com (eapex1hubcas4.st.com [10.80.176.69]) by zeta.dmz-ap.st.com (STMicroelectronics) with ESMTP id E069CBB4; Thu, 13 Dec 2012 11:41:30 +0000 (GMT) Received: from localhost (10.199.82.27) by Webmail-ap.st.com (10.80.176.7) with Microsoft SMTP Server (TLS) id 8.3.192.1; Thu, 13 Dec 2012 19:41:30 +0800 From: Vipin Kumar To: , Date: Thu, 13 Dec 2012 17:11:23 +0530 Message-ID: <1271842b3dc8825f6fbedf8556a21b4302ef5f07.1355398350.git.vipin.kumar@st.com> X-Mailer: git-send-email 1.8.0 MIME-Version: 1.0 Cc: Armando Visconti , spear-devel@list.st.com Subject: [U-Boot] [PATCH v3] spi/arm-pl022: Add support for ARM PL022 spi controller X-BeenThere: u-boot@lists.denx.de X-Mailman-Version: 2.1.11 Precedence: list List-Id: U-Boot discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: u-boot-bounces@lists.denx.de Errors-To: u-boot-bounces@lists.denx.de From: Armando Visconti This patch adds the support for the ARM PL022 SPI controller for the standard variant (0x00041022), which has a 16bit wide and 8 locations deep TX/RX FIFO. Signed-off-by: Armando Visconti Signed-off-by: Vipin Kumar Acked-by: Stefan Roese --- Changes in v3 Added void to spi_init arguments Used readl/writel in place of u16 accessors Fix: Provided address of register in place of value to readl/writel IO accessors Tested with spear1340-evb Stefan, I have not added your Acked-by because the patch has changed after you acked it. drivers/spi/Makefile | 1 + drivers/spi/pl022_spi.c | 310 ++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 311 insertions(+) create mode 100644 drivers/spi/pl022_spi.c diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile index 824d357..3a4e4b0 100644 --- a/drivers/spi/Makefile +++ b/drivers/spi/Makefile @@ -42,6 +42,7 @@ COBJS-$(CONFIG_MXC_SPI) += mxc_spi.o COBJS-$(CONFIG_MXS_SPI) += mxs_spi.o COBJS-$(CONFIG_OC_TINY_SPI) += oc_tiny_spi.o COBJS-$(CONFIG_OMAP3_SPI) += omap3_spi.o +COBJS-$(CONFIG_PL022_SPI) += pl022_spi.o COBJS-$(CONFIG_SOFT_SPI) += soft_spi.o COBJS-$(CONFIG_SH_SPI) += sh_spi.o COBJS-$(CONFIG_FSL_ESPI) += fsl_espi.o diff --git a/drivers/spi/pl022_spi.c b/drivers/spi/pl022_spi.c new file mode 100644 index 0000000..86d65ae --- /dev/null +++ b/drivers/spi/pl022_spi.c @@ -0,0 +1,310 @@ +/* + * (C) Copyright 2012 + * Armando Visconti, ST Microelectronics, armando.visconti@st.com. + * + * Driver for ARM PL022 SPI Controller. Based on atmel_spi.c + * by Atmel Corporation. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of + * the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, + * MA 02111-1307 USA + */ + +#include +#include +#include +#include +#include + +/* SSP registers mapping */ +struct pl022 { + u32 ssp_cr0; /* 0x000 */ + u32 ssp_cr1; /* 0x004 */ + u32 ssp_dr; /* 0x008 */ + u32 ssp_sr; /* 0x00c */ + u32 ssp_cpsr; /* 0x010 */ + u32 ssp_imsc; /* 0x014 */ + u32 ssp_ris; /* 0x018 */ + u32 ssp_mis; /* 0x01c */ + u32 ssp_icr; /* 0x020 */ + u32 ssp_dmacr; /* 0x024 */ + u8 reserved_1[0x080 - 0x028]; + u32 ssp_itcr; /* 0x080 */ + u32 ssp_itip; /* 0x084 */ + u32 ssp_itop; /* 0x088 */ + u32 ssp_tdr; /* 0x08c */ + u8 reserved_2[0xFE0 - 0x090]; + u32 ssp_pid0; /* 0xfe0 */ + u32 ssp_pid1; /* 0xfe4 */ + u32 ssp_pid2; /* 0xfe8 */ + u32 ssp_pid3; /* 0xfec */ + u32 ssp_cid0; /* 0xff0 */ + u32 ssp_cid1; /* 0xff4 */ + u32 ssp_cid2; /* 0xff8 */ + u32 ssp_cid3; /* 0xffc */ +}; + +/* SSP Control Register 0 - SSP_CR0 */ +#define SSP_CR0_SPO (0x1 << 6) +#define SSP_CR0_SPH (0x1 << 7) +#define SSP_CR0_8BIT_MODE (0x07) +#define SSP_SCR_MAX (0xFF) +#define SSP_SCR_SHFT 8 + +/* SSP Control Register 0 - SSP_CR1 */ +#define SSP_CR1_MASK_SSE (0x1 << 1) + +#define SSP_CPSR_MAX (0xFE) + +/* SSP Status Register - SSP_SR */ +#define SSP_SR_MASK_TFE (0x1 << 0) /* Transmit FIFO empty */ +#define SSP_SR_MASK_TNF (0x1 << 1) /* Transmit FIFO not full */ +#define SSP_SR_MASK_RNE (0x1 << 2) /* Receive FIFO not empty */ +#define SSP_SR_MASK_RFF (0x1 << 3) /* Receive FIFO full */ +#define SSP_SR_MASK_BSY (0x1 << 4) /* Busy Flag */ + +struct pl022_spi_slave { + struct spi_slave slave; + void *regs; + unsigned int freq; +}; + +static inline struct pl022_spi_slave *to_pl022_spi(struct spi_slave *slave) +{ + return container_of(slave, struct pl022_spi_slave, slave); +} + +/* + * Following three functions should be provided by the + * board support package. + */ +int __weak spi_cs_is_valid(unsigned int bus, unsigned int cs) +{ + return 1; +} + +void __weak spi_cs_activate(struct spi_slave *slave) +{ + /* do nothing */ +} + +void __weak spi_cs_deactivate(struct spi_slave *slave) +{ + /* do nothing */ +} + +void spi_init(void) +{ + /* do nothing */ +} + +/* + * ARM PL022 exists in different 'flavors'. + * This drivers currently support the standard variant (0x00041022), that has a + * 16bit wide and 8 locations deep TX/RX FIFO. + */ +static int pl022_is_supported(struct pl022_spi_slave *ps) +{ + struct pl022 *pl022 = (struct pl022 *)ps->regs; + + /* PL022 version is 0x00041022 */ + if ((readl(&pl022->ssp_pid0) == 0x22) && + (readl(&pl022->ssp_pid1) == 0x10) && + ((readl(&pl022->ssp_pid2) & 0xf) == 0x04) && + (readl(&pl022->ssp_pid3) == 0x00)) + return 1; + + return 0; +} + +struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs, + unsigned int max_hz, unsigned int mode) +{ + struct pl022_spi_slave *ps; + struct pl022 *pl022; + u16 scr = 1, prescaler, cr0 = 0, cpsr = 0; + + if (!spi_cs_is_valid(bus, cs)) + return NULL; + + ps = malloc(sizeof(*ps)); + if (!ps) + return NULL; + + ps->slave.bus = bus; + ps->slave.cs = cs; + ps->freq = max_hz; + + switch (bus) { + case 0: + ps->regs = (void *)CONFIG_SYS_SPI_BASE; + break; +#ifdef CONFIG_SYS_SPI_BASE1 + case 1: + ps->regs = (void *)CONFIG_SYS_SPI_BASE1; + break; +#endif +#ifdef CONFIG_SYS_SPI_BASE2 + case 2: + ps->regs = (void *)CONFIG_SYS_SPI_BASE2; + break; +#endif +#ifdef CONFIG_SYS_SPI_BASE3 + case 3: + ps->regs = (void *)CONFIG_SYS_SPI_BASE3; + break; +#endif + default: + free(ps); + return NULL; + } + + pl022 = (struct pl022 *)ps->regs; + + /* Check the PL022 version */ + if (!pl022_is_supported(ps)) { + free(ps); + return NULL; + } + + /* Set requested polarity and 8bit mode */ + cr0 = SSP_CR0_8BIT_MODE; + cr0 |= (mode & SPI_CPHA) ? SSP_CR0_SPH : 0; + cr0 |= (mode & SPI_CPOL) ? SSP_CR0_SPO : 0; + + writel(cr0, &pl022->ssp_cr0); + + /* Program the SSPClk frequency */ + prescaler = CONFIG_SYS_SPI_CLK / ps->freq; + + if (prescaler <= 0xFF) + cpsr = prescaler; + else { + for (scr = 1; scr <= SSP_SCR_MAX; scr++) { + if (!(prescaler % scr)) { + cpsr = prescaler / scr; + if (cpsr <= SSP_CPSR_MAX) + break; + } + } + + if (scr > SSP_SCR_MAX) { + scr = SSP_SCR_MAX; + cpsr = prescaler / scr; + cpsr &= SSP_CPSR_MAX; + } + } + + if (cpsr & 0x1) + cpsr++; + + writel(cpsr, &pl022->ssp_cpsr); + cr0 = readl(&pl022->ssp_cr0); + writel(cr0 | (scr - 1) << SSP_SCR_SHFT, &pl022->ssp_cr0); + + return &ps->slave; +} + +void spi_free_slave(struct spi_slave *slave) +{ + struct pl022_spi_slave *ps = to_pl022_spi(slave); + + free(ps); +} + +int spi_claim_bus(struct spi_slave *slave) +{ + struct pl022_spi_slave *ps = to_pl022_spi(slave); + struct pl022 *pl022 = (struct pl022 *)ps->regs; + + /* Enable the SPI hardware */ + setbits_le32(&pl022->ssp_cr1, SSP_CR1_MASK_SSE); + + return 0; +} + +void spi_release_bus(struct spi_slave *slave) +{ + struct pl022_spi_slave *ps = to_pl022_spi(slave); + struct pl022 *pl022 = (struct pl022 *)ps->regs; + + /* Disable the SPI hardware */ + writel(0x0, &pl022->ssp_cr1); +} + +int spi_xfer(struct spi_slave *slave, unsigned int bitlen, + const void *dout, void *din, unsigned long flags) +{ + struct pl022_spi_slave *ps = to_pl022_spi(slave); + struct pl022 *pl022 = (struct pl022 *)ps->regs; + u32 len_tx = 0, len_rx = 0, len; + u32 ret = 0; + const u8 *txp = dout; + u8 *rxp = din, value; + + if (bitlen == 0) + /* Finish any previously submitted transfers */ + goto out; + + /* + * TODO: The controller can do non-multiple-of-8 bit + * transfers, but this driver currently doesn't support it. + * + * It's also not clear how such transfers are supposed to be + * represented as a stream of bytes...this is a limitation of + * the current SPI interface. + */ + if (bitlen % 8) { + ret = -1; + + /* Errors always terminate an ongoing transfer */ + flags |= SPI_XFER_END; + goto out; + } + + len = bitlen / 8; + + if (flags & SPI_XFER_BEGIN) + spi_cs_activate(slave); + + while (len_tx < len) { + if (readl(&pl022->ssp_sr) & SSP_SR_MASK_TNF) { + value = (txp != NULL) ? *txp++ : 0; + writel(value, &pl022->ssp_dr); + len_tx++; + } + + if (readl(&pl022->ssp_sr) & SSP_SR_MASK_RNE) { + value = readl(&pl022->ssp_dr); + if (rxp) + *rxp++ = value; + len_rx++; + } + } + + while (len_rx < len_tx) { + if (readl(&pl022->ssp_sr) & SSP_SR_MASK_RNE) { + value = readl(&pl022->ssp_dr); + if (rxp) + *rxp++ = value; + len_rx++; + } + } + +out: + if (flags & SPI_XFER_END) + spi_cs_deactivate(slave); + + return ret; +}