| Message ID | 20210803113134.2262882-8-iwona.winiarska@intel.com |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
| Series | Introduce PECI subsystem | expand |
On Tue, Aug 3, 2021 at 4:35 AM Iwona Winiarska <iwona.winiarska@intel.com> wrote: > > From: Jae Hyun Yoo <jae.hyun.yoo@linux.intel.com> > > ASPEED AST24xx/AST25xx/AST26xx SoCs supports the PECI electrical > interface (a.k.a PECI wire). Maybe a one sentence blurb here and in the Kconfig reminding people why they should care if they have a PECI driver or not? > > Signed-off-by: Jae Hyun Yoo <jae.hyun.yoo@linux.intel.com> > Co-developed-by: Iwona Winiarska <iwona.winiarska@intel.com> > Signed-off-by: Iwona Winiarska <iwona.winiarska@intel.com> > Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> > --- > MAINTAINERS | 9 + > drivers/peci/Kconfig | 6 + > drivers/peci/Makefile | 3 + > drivers/peci/controller/Kconfig | 16 + > drivers/peci/controller/Makefile | 3 + > drivers/peci/controller/peci-aspeed.c | 445 ++++++++++++++++++++++++++ > 6 files changed, 482 insertions(+) > create mode 100644 drivers/peci/controller/Kconfig > create mode 100644 drivers/peci/controller/Makefile > create mode 100644 drivers/peci/controller/peci-aspeed.c > > diff --git a/MAINTAINERS b/MAINTAINERS > index d411974aaa5e..6e9d53ff68ab 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -2866,6 +2866,15 @@ S: Maintained > F: Documentation/hwmon/asc7621.rst > F: drivers/hwmon/asc7621.c > > +ASPEED PECI CONTROLLER > +M: Iwona Winiarska <iwona.winiarska@intel.com> > +M: Jae Hyun Yoo <jae.hyun.yoo@linux.intel.com> > +L: linux-aspeed@lists.ozlabs.org (moderated for non-subscribers) > +L: openbmc@lists.ozlabs.org (moderated for non-subscribers) > +S: Supported > +F: Documentation/devicetree/bindings/peci/peci-aspeed.yaml > +F: drivers/peci/controller/peci-aspeed.c > + > ASPEED PINCTRL DRIVERS > M: Andrew Jeffery <andrew@aj.id.au> > L: linux-aspeed@lists.ozlabs.org (moderated for non-subscribers) > diff --git a/drivers/peci/Kconfig b/drivers/peci/Kconfig > index 71a4ad81225a..99279df97a78 100644 > --- a/drivers/peci/Kconfig > +++ b/drivers/peci/Kconfig > @@ -13,3 +13,9 @@ menuconfig PECI > > This support is also available as a module. If so, the module > will be called peci. > + > +if PECI > + > +source "drivers/peci/controller/Kconfig" > + > +endif # PECI > diff --git a/drivers/peci/Makefile b/drivers/peci/Makefile > index e789a354e842..926d8df15cbd 100644 > --- a/drivers/peci/Makefile > +++ b/drivers/peci/Makefile > @@ -3,3 +3,6 @@ > # Core functionality > peci-y := core.o > obj-$(CONFIG_PECI) += peci.o > + > +# Hardware specific bus drivers > +obj-y += controller/ > diff --git a/drivers/peci/controller/Kconfig b/drivers/peci/controller/Kconfig > new file mode 100644 > index 000000000000..6d48df08db1c > --- /dev/null > +++ b/drivers/peci/controller/Kconfig > @@ -0,0 +1,16 @@ > +# SPDX-License-Identifier: GPL-2.0-only > + > +config PECI_ASPEED > + tristate "ASPEED PECI support" > + depends on ARCH_ASPEED || COMPILE_TEST > + depends on OF > + depends on HAS_IOMEM > + help > + This option enables PECI controller driver for ASPEED AST2400, > + AST2500 and AST2600 SoCs. > + > + Say Y here if your system runs on ASPEED SoC and you are using it > + as BMC for Intel platform. > + > + This driver can also be built as a module. If so, the module will > + be called peci-aspeed. > diff --git a/drivers/peci/controller/Makefile b/drivers/peci/controller/Makefile > new file mode 100644 > index 000000000000..022c28ef1bf0 > --- /dev/null > +++ b/drivers/peci/controller/Makefile > @@ -0,0 +1,3 @@ > +# SPDX-License-Identifier: GPL-2.0-only > + > +obj-$(CONFIG_PECI_ASPEED) += peci-aspeed.o > diff --git a/drivers/peci/controller/peci-aspeed.c b/drivers/peci/controller/peci-aspeed.c > new file mode 100644 > index 000000000000..1d708c983749 > --- /dev/null > +++ b/drivers/peci/controller/peci-aspeed.c > @@ -0,0 +1,445 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +// Copyright (C) 2012-2017 ASPEED Technology Inc. > +// Copyright (c) 2018-2021 Intel Corporation Why different copyright capitalization? > + > +#include <linux/bitfield.h> > +#include <linux/clk.h> > +#include <linux/delay.h> > +#include <linux/interrupt.h> > +#include <linux/io.h> > +#include <linux/iopoll.h> > +#include <linux/jiffies.h> > +#include <linux/module.h> > +#include <linux/of.h> > +#include <linux/peci.h> > +#include <linux/platform_device.h> > +#include <linux/reset.h> > + > +#include <asm/unaligned.h> Why is this included? > + > +/* ASPEED PECI Registers */ > +/* Control Register */ > +#define ASPEED_PECI_CTRL 0x00 > +#define ASPEED_PECI_CTRL_SAMPLING_MASK GENMASK(19, 16) > +#define ASPEED_PECI_CTRL_RD_MODE_MASK GENMASK(13, 12) > +#define ASPEED_PECI_CTRL_RD_MODE_DBG BIT(13) > +#define ASPEED_PECI_CTRL_RD_MODE_COUNT BIT(12) > +#define ASPEED_PECI_CTRL_CLK_SOURCE BIT(11) > +#define ASPEED_PECI_CTRL_CLK_DIV_MASK GENMASK(10, 8) > +#define ASPEED_PECI_CTRL_INVERT_OUT BIT(7) > +#define ASPEED_PECI_CTRL_INVERT_IN BIT(6) > +#define ASPEED_PECI_CTRL_BUS_CONTENTION_EN BIT(5) > +#define ASPEED_PECI_CTRL_PECI_EN BIT(4) > +#define ASPEED_PECI_CTRL_PECI_CLK_EN BIT(0) > + > +/* Timing Negotiation Register */ > +#define ASPEED_PECI_TIMING_NEGOTIATION 0x04 > +#define ASPEED_PECI_T_NEGO_MSG_MASK GENMASK(15, 8) > +#define ASPEED_PECI_T_NEGO_ADDR_MASK GENMASK(7, 0) > + > +/* Command Register */ > +#define ASPEED_PECI_CMD 0x08 > +#define ASPEED_PECI_CMD_PIN_MONITORING BIT(31) > +#define ASPEED_PECI_CMD_STS_MASK GENMASK(27, 24) > +#define ASPEED_PECI_CMD_STS_ADDR_T_NEGO 0x3 > +#define ASPEED_PECI_CMD_IDLE_MASK \ > + (ASPEED_PECI_CMD_STS_MASK | ASPEED_PECI_CMD_PIN_MONITORING) > +#define ASPEED_PECI_CMD_FIRE BIT(0) > + > +/* Read/Write Length Register */ > +#define ASPEED_PECI_RW_LENGTH 0x0c > +#define ASPEED_PECI_AW_FCS_EN BIT(31) > +#define ASPEED_PECI_RD_LEN_MASK GENMASK(23, 16) > +#define ASPEED_PECI_WR_LEN_MASK GENMASK(15, 8) > +#define ASPEED_PECI_TARGET_ADDR_MASK GENMASK(7, 0) > + > +/* Expected FCS Data Register */ > +#define ASPEED_PECI_EXPECTED_FCS 0x10 > +#define ASPEED_PECI_EXPECTED_RD_FCS_MASK GENMASK(23, 16) > +#define ASPEED_PECI_EXPECTED_AW_FCS_AUTO_MASK GENMASK(15, 8) > +#define ASPEED_PECI_EXPECTED_WR_FCS_MASK GENMASK(7, 0) > + > +/* Captured FCS Data Register */ > +#define ASPEED_PECI_CAPTURED_FCS 0x14 > +#define ASPEED_PECI_CAPTURED_RD_FCS_MASK GENMASK(23, 16) > +#define ASPEED_PECI_CAPTURED_WR_FCS_MASK GENMASK(7, 0) > + > +/* Interrupt Register */ > +#define ASPEED_PECI_INT_CTRL 0x18 > +#define ASPEED_PECI_TIMING_NEGO_SEL_MASK GENMASK(31, 30) > +#define ASPEED_PECI_1ST_BIT_OF_ADDR_NEGO 0 > +#define ASPEED_PECI_2ND_BIT_OF_ADDR_NEGO 1 > +#define ASPEED_PECI_MESSAGE_NEGO 2 > +#define ASPEED_PECI_INT_MASK GENMASK(4, 0) > +#define ASPEED_PECI_INT_BUS_TIMEOUT BIT(4) > +#define ASPEED_PECI_INT_BUS_CONTENTION BIT(3) > +#define ASPEED_PECI_INT_WR_FCS_BAD BIT(2) > +#define ASPEED_PECI_INT_WR_FCS_ABORT BIT(1) > +#define ASPEED_PECI_INT_CMD_DONE BIT(0) > + > +/* Interrupt Status Register */ > +#define ASPEED_PECI_INT_STS 0x1c > +#define ASPEED_PECI_INT_TIMING_RESULT_MASK GENMASK(29, 16) > + /* bits[4..0]: Same bit fields in the 'Interrupt Register' */ > + > +/* Rx/Tx Data Buffer Registers */ > +#define ASPEED_PECI_WR_DATA0 0x20 > +#define ASPEED_PECI_WR_DATA1 0x24 > +#define ASPEED_PECI_WR_DATA2 0x28 > +#define ASPEED_PECI_WR_DATA3 0x2c > +#define ASPEED_PECI_RD_DATA0 0x30 > +#define ASPEED_PECI_RD_DATA1 0x34 > +#define ASPEED_PECI_RD_DATA2 0x38 > +#define ASPEED_PECI_RD_DATA3 0x3c > +#define ASPEED_PECI_WR_DATA4 0x40 > +#define ASPEED_PECI_WR_DATA5 0x44 > +#define ASPEED_PECI_WR_DATA6 0x48 > +#define ASPEED_PECI_WR_DATA7 0x4c > +#define ASPEED_PECI_RD_DATA4 0x50 > +#define ASPEED_PECI_RD_DATA5 0x54 > +#define ASPEED_PECI_RD_DATA6 0x58 > +#define ASPEED_PECI_RD_DATA7 0x5c > +#define ASPEED_PECI_DATA_BUF_SIZE_MAX 32 > + > +/* Timing Negotiation */ > +#define ASPEED_PECI_RD_SAMPLING_POINT_DEFAULT 8 > +#define ASPEED_PECI_RD_SAMPLING_POINT_MAX (BIT(4) - 1) > +#define ASPEED_PECI_CLK_DIV_DEFAULT 0 > +#define ASPEED_PECI_CLK_DIV_MAX (BIT(3) - 1) > +#define ASPEED_PECI_MSG_TIMING_DEFAULT 1 > +#define ASPEED_PECI_MSG_TIMING_MAX (BIT(8) - 1) > +#define ASPEED_PECI_ADDR_TIMING_DEFAULT 1 > +#define ASPEED_PECI_ADDR_TIMING_MAX (BIT(8) - 1) > + > +/* Timeout */ > +#define ASPEED_PECI_IDLE_CHECK_TIMEOUT_US (50 * USEC_PER_MSEC) > +#define ASPEED_PECI_IDLE_CHECK_INTERVAL_US (10 * USEC_PER_MSEC) > +#define ASPEED_PECI_CMD_TIMEOUT_MS_DEFAULT (1000) > +#define ASPEED_PECI_CMD_TIMEOUT_MS_MAX (1000) > + > +struct aspeed_peci { > + struct peci_controller *controller; > + struct device *dev; > + void __iomem *base; > + struct clk *clk; > + struct reset_control *rst; > + int irq; > + spinlock_t lock; /* to sync completion status handling */ > + struct completion xfer_complete; > + u32 status; > + u32 cmd_timeout_ms; > + u32 msg_timing; > + u32 addr_timing; > + u32 rd_sampling_point; > + u32 clk_div; > +}; > + > +static void aspeed_peci_init_regs(struct aspeed_peci *priv) > +{ > + u32 val; > + > + val = FIELD_PREP(ASPEED_PECI_CTRL_CLK_DIV_MASK, ASPEED_PECI_CLK_DIV_DEFAULT); > + val |= ASPEED_PECI_CTRL_PECI_CLK_EN; > + writel(val, priv->base + ASPEED_PECI_CTRL); > + /* > + * Timing negotiation period setting. > + * The unit of the programmed value is 4 times of PECI clock period. > + */ > + val = FIELD_PREP(ASPEED_PECI_T_NEGO_MSG_MASK, priv->msg_timing); > + val |= FIELD_PREP(ASPEED_PECI_T_NEGO_ADDR_MASK, priv->addr_timing); > + writel(val, priv->base + ASPEED_PECI_TIMING_NEGOTIATION); > + > + /* Clear interrupts */ > + val = readl(priv->base + ASPEED_PECI_INT_STS) | ASPEED_PECI_INT_MASK; > + writel(val, priv->base + ASPEED_PECI_INT_STS); > + > + /* Set timing negotiation mode and enable interrupts */ > + val = FIELD_PREP(ASPEED_PECI_TIMING_NEGO_SEL_MASK, ASPEED_PECI_1ST_BIT_OF_ADDR_NEGO); > + val |= ASPEED_PECI_INT_MASK; > + writel(val, priv->base + ASPEED_PECI_INT_CTRL); > + > + val = FIELD_PREP(ASPEED_PECI_CTRL_SAMPLING_MASK, priv->rd_sampling_point); > + val |= FIELD_PREP(ASPEED_PECI_CTRL_CLK_DIV_MASK, priv->clk_div); > + val |= ASPEED_PECI_CTRL_PECI_EN; > + val |= ASPEED_PECI_CTRL_PECI_CLK_EN; > + writel(val, priv->base + ASPEED_PECI_CTRL); > +} > + > +static inline int aspeed_peci_check_idle(struct aspeed_peci *priv) > +{ > + u32 cmd_sts = readl(priv->base + ASPEED_PECI_CMD); > + > + if (FIELD_GET(ASPEED_PECI_CMD_STS_MASK, cmd_sts) == ASPEED_PECI_CMD_STS_ADDR_T_NEGO) > + aspeed_peci_init_regs(priv); > + > + return readl_poll_timeout(priv->base + ASPEED_PECI_CMD, > + cmd_sts, > + !(cmd_sts & ASPEED_PECI_CMD_IDLE_MASK), > + ASPEED_PECI_IDLE_CHECK_INTERVAL_US, > + ASPEED_PECI_IDLE_CHECK_TIMEOUT_US); > +} > + > +static int aspeed_peci_xfer(struct peci_controller *controller, > + u8 addr, struct peci_request *req) > +{ > + struct aspeed_peci *priv = dev_get_drvdata(controller->dev.parent); > + unsigned long flags, timeout = msecs_to_jiffies(priv->cmd_timeout_ms); > + u32 peci_head; > + int ret; > + > + if (req->tx.len > ASPEED_PECI_DATA_BUF_SIZE_MAX || > + req->rx.len > ASPEED_PECI_DATA_BUF_SIZE_MAX) > + return -EINVAL; > + > + /* Check command sts and bus idle state */ > + ret = aspeed_peci_check_idle(priv); > + if (ret) > + return ret; /* -ETIMEDOUT */ > + > + spin_lock_irqsave(&priv->lock, flags); > + reinit_completion(&priv->xfer_complete); > + > + peci_head = FIELD_PREP(ASPEED_PECI_TARGET_ADDR_MASK, addr) | > + FIELD_PREP(ASPEED_PECI_WR_LEN_MASK, req->tx.len) | > + FIELD_PREP(ASPEED_PECI_RD_LEN_MASK, req->rx.len); > + > + writel(peci_head, priv->base + ASPEED_PECI_RW_LENGTH); > + > + memcpy_toio(priv->base + ASPEED_PECI_WR_DATA0, req->tx.buf, min_t(u8, req->tx.len, 16)); > + if (req->tx.len > 16) > + memcpy_toio(priv->base + ASPEED_PECI_WR_DATA4, req->tx.buf + 16, > + req->tx.len - 16); > + > + dev_dbg(priv->dev, "HEAD : 0x%08x\n", peci_head); > + print_hex_dump_bytes("TX : ", DUMP_PREFIX_NONE, req->tx.buf, req->tx.len); On CONFIG_DYNAMIC_DEBUG=n builds the kernel will do all the work of reading through this buffer, but skip emitting it. Are you sure you want to pay that overhead for every transaction? > + > + priv->status = 0; > + writel(ASPEED_PECI_CMD_FIRE, priv->base + ASPEED_PECI_CMD); > + spin_unlock_irqrestore(&priv->lock, flags); > + > + ret = wait_for_completion_interruptible_timeout(&priv->xfer_complete, timeout); spin_lock_irqsave() says "I don't know if interrupts are disabled already, so I'll save the state, whatever it is, and restore later" wait_for_completion_interruptible_timeout() says "I know I am in a sleepable context where interrupts are enabled" So, one of those is wrong, i.e. should it be spin_{lock,unlock}_irq()? > + if (ret < 0) > + return ret; > + > + if (ret == 0) { > + dev_dbg(priv->dev, "Timeout waiting for a response!\n"); > + return -ETIMEDOUT; > + } > + > + spin_lock_irqsave(&priv->lock, flags); > + > + writel(0, priv->base + ASPEED_PECI_CMD); > + > + if (priv->status != ASPEED_PECI_INT_CMD_DONE) { > + spin_unlock_irqrestore(&priv->lock, flags); > + dev_dbg(priv->dev, "No valid response!\n"); > + return -EIO; > + } > + > + spin_unlock_irqrestore(&priv->lock, flags); > + > + memcpy_fromio(req->rx.buf, priv->base + ASPEED_PECI_RD_DATA0, min_t(u8, req->rx.len, 16)); > + if (req->rx.len > 16) > + memcpy_fromio(req->rx.buf + 16, priv->base + ASPEED_PECI_RD_DATA4, > + req->rx.len - 16); > + > + print_hex_dump_bytes("RX : ", DUMP_PREFIX_NONE, req->rx.buf, req->rx.len); > + > + return 0; > +} > + > +static irqreturn_t aspeed_peci_irq_handler(int irq, void *arg) > +{ > + struct aspeed_peci *priv = arg; > + u32 status; > + > + spin_lock(&priv->lock); > + status = readl(priv->base + ASPEED_PECI_INT_STS); > + writel(status, priv->base + ASPEED_PECI_INT_STS); > + priv->status |= (status & ASPEED_PECI_INT_MASK); > + > + /* > + * In most cases, interrupt bits will be set one by one but also note > + * that multiple interrupt bits could be set at the same time. > + */ > + if (status & ASPEED_PECI_INT_BUS_TIMEOUT) > + dev_dbg_ratelimited(priv->dev, "ASPEED_PECI_INT_BUS_TIMEOUT\n"); > + > + if (status & ASPEED_PECI_INT_BUS_CONTENTION) > + dev_dbg_ratelimited(priv->dev, "ASPEED_PECI_INT_BUS_CONTENTION\n"); > + > + if (status & ASPEED_PECI_INT_WR_FCS_BAD) > + dev_dbg_ratelimited(priv->dev, "ASPEED_PECI_INT_WR_FCS_BAD\n"); > + > + if (status & ASPEED_PECI_INT_WR_FCS_ABORT) > + dev_dbg_ratelimited(priv->dev, "ASPEED_PECI_INT_WR_FCS_ABORT\n"); Are you sure these would not be better as tracepoints? If you're debugging an interrupt related failure, the ratelimiting might get in your way when you really need to know when one of these error interrupts fire relative to another event. > + > + /* > + * All commands should be ended up with a ASPEED_PECI_INT_CMD_DONE bit > + * set even in an error case. > + */ > + if (status & ASPEED_PECI_INT_CMD_DONE) > + complete(&priv->xfer_complete); Hmm, no need to check if there was a sequencing error, like a command was never submitted? > + > + spin_unlock(&priv->lock); > + > + return IRQ_HANDLED; > +} > + > +static void aspeed_peci_property_sanitize(struct device *dev, const char *propname, > + u32 min, u32 max, u32 default_val, u32 *propval) > +{ > + u32 val; > + int ret; > + > + ret = device_property_read_u32(dev, propname, &val); > + if (ret) { > + val = default_val; > + } else if (val > max || val < min) { > + dev_warn(dev, "Invalid %s: %u, falling back to: %u\n", > + propname, val, default_val); > + > + val = default_val; > + } > + > + *propval = val; > +} > + > +static void aspeed_peci_property_setup(struct aspeed_peci *priv) > +{ > + aspeed_peci_property_sanitize(priv->dev, "aspeed,clock-divider", > + 0, ASPEED_PECI_CLK_DIV_MAX, > + ASPEED_PECI_CLK_DIV_DEFAULT, &priv->clk_div); > + aspeed_peci_property_sanitize(priv->dev, "aspeed,msg-timing", > + 0, ASPEED_PECI_MSG_TIMING_MAX, > + ASPEED_PECI_MSG_TIMING_DEFAULT, &priv->msg_timing); > + aspeed_peci_property_sanitize(priv->dev, "aspeed,addr-timing", > + 0, ASPEED_PECI_ADDR_TIMING_MAX, > + ASPEED_PECI_ADDR_TIMING_DEFAULT, &priv->addr_timing); > + aspeed_peci_property_sanitize(priv->dev, "aspeed,rd-sampling-point", > + 0, ASPEED_PECI_RD_SAMPLING_POINT_MAX, > + ASPEED_PECI_RD_SAMPLING_POINT_DEFAULT, > + &priv->rd_sampling_point); > + aspeed_peci_property_sanitize(priv->dev, "cmd-timeout-ms", > + 1, ASPEED_PECI_CMD_TIMEOUT_MS_MAX, > + ASPEED_PECI_CMD_TIMEOUT_MS_DEFAULT, &priv->cmd_timeout_ms); > +} > + > +static struct peci_controller_ops aspeed_ops = { > + .xfer = aspeed_peci_xfer, > +}; > + > +static void aspeed_peci_reset_control_release(void *data) > +{ > + reset_control_assert(data); > +} > + > +int aspeed_peci_reset_control_deassert(struct device *dev, struct reset_control *rst) I'd recommend naming this devm_aspeed_peci_reset_control_deassert(), because I came looking here from reading probe for why there was no reassertion of reset on driver ->remove(). > +{ > + int ret; > + > + ret = reset_control_deassert(rst); > + if (ret) > + return ret; > + > + return devm_add_action_or_reset(dev, aspeed_peci_reset_control_release, rst); > +} > + > +static void aspeed_peci_clk_release(void *data) > +{ > + clk_disable_unprepare(data); > +} > + > +static int aspeed_peci_clk_enable(struct device *dev, struct clk *clk) ...ditto on the devm prefix, just to speed readability. > +{ > + int ret; > + > + ret = clk_prepare_enable(clk); > + if (ret) > + return ret; > + > + return devm_add_action_or_reset(dev, aspeed_peci_clk_release, clk); > +} > + > +static int aspeed_peci_probe(struct platform_device *pdev) > +{ > + struct peci_controller *controller; > + struct aspeed_peci *priv; > + int ret; > + > + priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); > + if (!priv) > + return -ENOMEM; > + > + priv->dev = &pdev->dev; > + dev_set_drvdata(priv->dev, priv); > + > + priv->base = devm_platform_ioremap_resource(pdev, 0); > + if (IS_ERR(priv->base)) > + return PTR_ERR(priv->base); > + > + priv->irq = platform_get_irq(pdev, 0); > + if (!priv->irq) > + return priv->irq; > + > + ret = devm_request_irq(&pdev->dev, priv->irq, aspeed_peci_irq_handler, > + 0, "peci-aspeed", priv); > + if (ret) > + return ret; > + > + init_completion(&priv->xfer_complete); > + spin_lock_init(&priv->lock); > + > + priv->rst = devm_reset_control_get(&pdev->dev, NULL); > + if (IS_ERR(priv->rst)) > + return dev_err_probe(priv->dev, PTR_ERR(priv->rst), > + "failed to get reset control\n"); > + > + ret = aspeed_peci_reset_control_deassert(priv->dev, priv->rst); > + if (ret) > + return dev_err_probe(priv->dev, ret, "cannot deassert reset control\n"); > + > + priv->clk = devm_clk_get(priv->dev, NULL); > + if (IS_ERR(priv->clk)) > + return dev_err_probe(priv->dev, PTR_ERR(priv->clk), "failed to get clk\n"); > + > + ret = aspeed_peci_clk_enable(priv->dev, priv->clk); > + if (ret) > + return dev_err_probe(priv->dev, ret, "failed to enable clock\n"); > + > + aspeed_peci_property_setup(priv); > + > + aspeed_peci_init_regs(priv); > + > + controller = devm_peci_controller_add(priv->dev, &aspeed_ops); > + if (IS_ERR(controller)) > + return dev_err_probe(priv->dev, PTR_ERR(controller), > + "failed to add aspeed peci controller\n"); > + > + priv->controller = controller; > + > + return 0; > +} > + > +static const struct of_device_id aspeed_peci_of_table[] = { > + { .compatible = "aspeed,ast2400-peci", }, > + { .compatible = "aspeed,ast2500-peci", }, > + { .compatible = "aspeed,ast2600-peci", }, > + { } > +}; > +MODULE_DEVICE_TABLE(of, aspeed_peci_of_table); > + > +static struct platform_driver aspeed_peci_driver = { > + .probe = aspeed_peci_probe, > + .driver = { > + .name = "peci-aspeed", > + .of_match_table = aspeed_peci_of_table, > + }, > +}; > +module_platform_driver(aspeed_peci_driver); > + > +MODULE_AUTHOR("Ryan Chen <ryan_chen@aspeedtech.com>"); > +MODULE_AUTHOR("Jae Hyun Yoo <jae.hyun.yoo@linux.intel.com>"); > +MODULE_DESCRIPTION("ASPEED PECI driver"); > +MODULE_LICENSE("GPL"); > +MODULE_IMPORT_NS(PECI); > -- > 2.31.1 >
On Wed, 2021-08-25 at 18:35 -0700, Dan Williams wrote: > On Tue, Aug 3, 2021 at 4:35 AM Iwona Winiarska > <iwona.winiarska@intel.com> wrote: > > > > From: Jae Hyun Yoo <jae.hyun.yoo@linux.intel.com> > > > > ASPEED AST24xx/AST25xx/AST26xx SoCs supports the PECI electrical > > interface (a.k.a PECI wire). > > Maybe a one sentence blurb here and in the Kconfig reminding people > why they should care if they have a PECI driver or not? Ok, I'll expand it a bit. > > > > > Signed-off-by: Jae Hyun Yoo <jae.hyun.yoo@linux.intel.com> > > Co-developed-by: Iwona Winiarska <iwona.winiarska@intel.com> > > Signed-off-by: Iwona Winiarska <iwona.winiarska@intel.com> > > Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> > > --- > > MAINTAINERS | 9 + > > drivers/peci/Kconfig | 6 + > > drivers/peci/Makefile | 3 + > > drivers/peci/controller/Kconfig | 16 + > > drivers/peci/controller/Makefile | 3 + > > drivers/peci/controller/peci-aspeed.c | 445 ++++++++++++++++++++++++++ > > 6 files changed, 482 insertions(+) > > create mode 100644 drivers/peci/controller/Kconfig > > create mode 100644 drivers/peci/controller/Makefile > > create mode 100644 drivers/peci/controller/peci-aspeed.c > > > > diff --git a/MAINTAINERS b/MAINTAINERS > > index d411974aaa5e..6e9d53ff68ab 100644 > > --- a/MAINTAINERS > > +++ b/MAINTAINERS > > @@ -2866,6 +2866,15 @@ S: Maintained > > F: Documentation/hwmon/asc7621.rst > > F: drivers/hwmon/asc7621.c > > > > +ASPEED PECI CONTROLLER > > +M: Iwona Winiarska <iwona.winiarska@intel.com> > > +M: Jae Hyun Yoo <jae.hyun.yoo@linux.intel.com> > > +L: linux-aspeed@lists.ozlabs.org (moderated for non-subscribers) > > +L: openbmc@lists.ozlabs.org (moderated for non-subscribers) > > +S: Supported > > +F: Documentation/devicetree/bindings/peci/peci-aspeed.yaml > > +F: drivers/peci/controller/peci-aspeed.c > > + > > ASPEED PINCTRL DRIVERS > > M: Andrew Jeffery <andrew@aj.id.au> > > L: linux-aspeed@lists.ozlabs.org (moderated for non-subscribers) > > diff --git a/drivers/peci/Kconfig b/drivers/peci/Kconfig > > index 71a4ad81225a..99279df97a78 100644 > > --- a/drivers/peci/Kconfig > > +++ b/drivers/peci/Kconfig > > @@ -13,3 +13,9 @@ menuconfig PECI > > > > This support is also available as a module. If so, the module > > will be called peci. > > + > > +if PECI > > + > > +source "drivers/peci/controller/Kconfig" > > + > > +endif # PECI > > diff --git a/drivers/peci/Makefile b/drivers/peci/Makefile > > index e789a354e842..926d8df15cbd 100644 > > --- a/drivers/peci/Makefile > > +++ b/drivers/peci/Makefile > > @@ -3,3 +3,6 @@ > > # Core functionality > > peci-y := core.o > > obj-$(CONFIG_PECI) += peci.o > > + > > +# Hardware specific bus drivers > > +obj-y += controller/ > > diff --git a/drivers/peci/controller/Kconfig > > b/drivers/peci/controller/Kconfig > > new file mode 100644 > > index 000000000000..6d48df08db1c > > --- /dev/null > > +++ b/drivers/peci/controller/Kconfig > > @@ -0,0 +1,16 @@ > > +# SPDX-License-Identifier: GPL-2.0-only > > + > > +config PECI_ASPEED > > + tristate "ASPEED PECI support" > > + depends on ARCH_ASPEED || COMPILE_TEST > > + depends on OF > > + depends on HAS_IOMEM > > + help > > + This option enables PECI controller driver for ASPEED AST2400, > > + AST2500 and AST2600 SoCs. > > + > > + Say Y here if your system runs on ASPEED SoC and you are using it > > + as BMC for Intel platform. > > + > > + This driver can also be built as a module. If so, the module will > > + be called peci-aspeed. > > diff --git a/drivers/peci/controller/Makefile > > b/drivers/peci/controller/Makefile > > new file mode 100644 > > index 000000000000..022c28ef1bf0 > > --- /dev/null > > +++ b/drivers/peci/controller/Makefile > > @@ -0,0 +1,3 @@ > > +# SPDX-License-Identifier: GPL-2.0-only > > + > > +obj-$(CONFIG_PECI_ASPEED) += peci-aspeed.o > > diff --git a/drivers/peci/controller/peci-aspeed.c > > b/drivers/peci/controller/peci-aspeed.c > > new file mode 100644 > > index 000000000000..1d708c983749 > > --- /dev/null > > +++ b/drivers/peci/controller/peci-aspeed.c > > @@ -0,0 +1,445 @@ > > +// SPDX-License-Identifier: GPL-2.0-only > > +// Copyright (C) 2012-2017 ASPEED Technology Inc. > > +// Copyright (c) 2018-2021 Intel Corporation > > Why different copyright capitalization? I'll make them consistent. > > > + > > +#include <linux/bitfield.h> > > +#include <linux/clk.h> > > +#include <linux/delay.h> > > +#include <linux/interrupt.h> > > +#include <linux/io.h> > > +#include <linux/iopoll.h> > > +#include <linux/jiffies.h> > > +#include <linux/module.h> > > +#include <linux/of.h> > > +#include <linux/peci.h> > > +#include <linux/platform_device.h> > > +#include <linux/reset.h> > > + > > +#include <asm/unaligned.h> > > Why is this included? Leftover - I'll remove it. > > > + > > +/* ASPEED PECI Registers */ > > +/* Control Register */ > > +#define ASPEED_PECI_CTRL 0x00 > > +#define ASPEED_PECI_CTRL_SAMPLING_MASK GENMASK(19, 16) > > +#define ASPEED_PECI_CTRL_RD_MODE_MASK GENMASK(13, 12) > > +#define ASPEED_PECI_CTRL_RD_MODE_DBG BIT(13) > > +#define ASPEED_PECI_CTRL_RD_MODE_COUNT BIT(12) > > +#define ASPEED_PECI_CTRL_CLK_SOURCE BIT(11) > > +#define ASPEED_PECI_CTRL_CLK_DIV_MASK GENMASK(10, 8) > > +#define ASPEED_PECI_CTRL_INVERT_OUT BIT(7) > > +#define ASPEED_PECI_CTRL_INVERT_IN BIT(6) > > +#define ASPEED_PECI_CTRL_BUS_CONTENTION_EN BIT(5) > > +#define ASPEED_PECI_CTRL_PECI_EN BIT(4) > > +#define ASPEED_PECI_CTRL_PECI_CLK_EN BIT(0) > > + > > +/* Timing Negotiation Register */ > > +#define ASPEED_PECI_TIMING_NEGOTIATION 0x04 > > +#define ASPEED_PECI_T_NEGO_MSG_MASK GENMASK(15, 8) > > +#define ASPEED_PECI_T_NEGO_ADDR_MASK GENMASK(7, 0) > > + > > +/* Command Register */ > > +#define ASPEED_PECI_CMD 0x08 > > +#define ASPEED_PECI_CMD_PIN_MONITORING BIT(31) > > +#define ASPEED_PECI_CMD_STS_MASK GENMASK(27, 24) > > +#define ASPEED_PECI_CMD_STS_ADDR_T_NEGO 0x3 > > +#define ASPEED_PECI_CMD_IDLE_MASK \ > > + (ASPEED_PECI_CMD_STS_MASK | ASPEED_PECI_CMD_PIN_MONITORING) > > +#define ASPEED_PECI_CMD_FIRE BIT(0) > > + > > +/* Read/Write Length Register */ > > +#define ASPEED_PECI_RW_LENGTH 0x0c > > +#define ASPEED_PECI_AW_FCS_EN BIT(31) > > +#define ASPEED_PECI_RD_LEN_MASK GENMASK(23, 16) > > +#define ASPEED_PECI_WR_LEN_MASK GENMASK(15, 8) > > +#define ASPEED_PECI_TARGET_ADDR_MASK GENMASK(7, 0) > > + > > +/* Expected FCS Data Register */ > > +#define ASPEED_PECI_EXPECTED_FCS 0x10 > > +#define ASPEED_PECI_EXPECTED_RD_FCS_MASK GENMASK(23, 16) > > +#define ASPEED_PECI_EXPECTED_AW_FCS_AUTO_MASK GENMASK(15, 8) > > +#define ASPEED_PECI_EXPECTED_WR_FCS_MASK GENMASK(7, 0) > > + > > +/* Captured FCS Data Register */ > > +#define ASPEED_PECI_CAPTURED_FCS 0x14 > > +#define ASPEED_PECI_CAPTURED_RD_FCS_MASK GENMASK(23, 16) > > +#define ASPEED_PECI_CAPTURED_WR_FCS_MASK GENMASK(7, 0) > > + > > +/* Interrupt Register */ > > +#define ASPEED_PECI_INT_CTRL 0x18 > > +#define ASPEED_PECI_TIMING_NEGO_SEL_MASK GENMASK(31, 30) > > +#define ASPEED_PECI_1ST_BIT_OF_ADDR_NEGO 0 > > +#define ASPEED_PECI_2ND_BIT_OF_ADDR_NEGO 1 > > +#define ASPEED_PECI_MESSAGE_NEGO 2 > > +#define ASPEED_PECI_INT_MASK GENMASK(4, 0) > > +#define ASPEED_PECI_INT_BUS_TIMEOUT BIT(4) > > +#define ASPEED_PECI_INT_BUS_CONTENTION BIT(3) > > +#define ASPEED_PECI_INT_WR_FCS_BAD BIT(2) > > +#define ASPEED_PECI_INT_WR_FCS_ABORT BIT(1) > > +#define ASPEED_PECI_INT_CMD_DONE BIT(0) > > + > > +/* Interrupt Status Register */ > > +#define ASPEED_PECI_INT_STS 0x1c > > +#define ASPEED_PECI_INT_TIMING_RESULT_MASK GENMASK(29, 16) > > + /* bits[4..0]: Same bit fields in the 'Interrupt Register' */ > > + > > +/* Rx/Tx Data Buffer Registers */ > > +#define ASPEED_PECI_WR_DATA0 0x20 > > +#define ASPEED_PECI_WR_DATA1 0x24 > > +#define ASPEED_PECI_WR_DATA2 0x28 > > +#define ASPEED_PECI_WR_DATA3 0x2c > > +#define ASPEED_PECI_RD_DATA0 0x30 > > +#define ASPEED_PECI_RD_DATA1 0x34 > > +#define ASPEED_PECI_RD_DATA2 0x38 > > +#define ASPEED_PECI_RD_DATA3 0x3c > > +#define ASPEED_PECI_WR_DATA4 0x40 > > +#define ASPEED_PECI_WR_DATA5 0x44 > > +#define ASPEED_PECI_WR_DATA6 0x48 > > +#define ASPEED_PECI_WR_DATA7 0x4c > > +#define ASPEED_PECI_RD_DATA4 0x50 > > +#define ASPEED_PECI_RD_DATA5 0x54 > > +#define ASPEED_PECI_RD_DATA6 0x58 > > +#define ASPEED_PECI_RD_DATA7 0x5c > > +#define ASPEED_PECI_DATA_BUF_SIZE_MAX 32 > > + > > +/* Timing Negotiation */ > > +#define ASPEED_PECI_RD_SAMPLING_POINT_DEFAULT 8 > > +#define ASPEED_PECI_RD_SAMPLING_POINT_MAX (BIT(4) - 1) > > +#define ASPEED_PECI_CLK_DIV_DEFAULT 0 > > +#define ASPEED_PECI_CLK_DIV_MAX (BIT(3) - 1) > > +#define ASPEED_PECI_MSG_TIMING_DEFAULT 1 > > +#define ASPEED_PECI_MSG_TIMING_MAX (BIT(8) - 1) > > +#define ASPEED_PECI_ADDR_TIMING_DEFAULT 1 > > +#define ASPEED_PECI_ADDR_TIMING_MAX (BIT(8) - 1) > > + > > +/* Timeout */ > > +#define ASPEED_PECI_IDLE_CHECK_TIMEOUT_US (50 * USEC_PER_MSEC) > > +#define ASPEED_PECI_IDLE_CHECK_INTERVAL_US (10 * USEC_PER_MSEC) > > +#define ASPEED_PECI_CMD_TIMEOUT_MS_DEFAULT (1000) > > +#define ASPEED_PECI_CMD_TIMEOUT_MS_MAX (1000) > > + > > +struct aspeed_peci { > > + struct peci_controller *controller; > > + struct device *dev; > > + void __iomem *base; > > + struct clk *clk; > > + struct reset_control *rst; > > + int irq; > > + spinlock_t lock; /* to sync completion status handling */ > > + struct completion xfer_complete; > > + u32 status; > > + u32 cmd_timeout_ms; > > + u32 msg_timing; > > + u32 addr_timing; > > + u32 rd_sampling_point; > > + u32 clk_div; > > +}; > > + > > +static void aspeed_peci_init_regs(struct aspeed_peci *priv) > > +{ > > + u32 val; > > + > > + val = FIELD_PREP(ASPEED_PECI_CTRL_CLK_DIV_MASK, > > ASPEED_PECI_CLK_DIV_DEFAULT); > > + val |= ASPEED_PECI_CTRL_PECI_CLK_EN; > > + writel(val, priv->base + ASPEED_PECI_CTRL); > > + /* > > + * Timing negotiation period setting. > > + * The unit of the programmed value is 4 times of PECI clock period. > > + */ > > + val = FIELD_PREP(ASPEED_PECI_T_NEGO_MSG_MASK, priv->msg_timing); > > + val |= FIELD_PREP(ASPEED_PECI_T_NEGO_ADDR_MASK, priv->addr_timing); > > + writel(val, priv->base + ASPEED_PECI_TIMING_NEGOTIATION); > > + > > + /* Clear interrupts */ > > + val = readl(priv->base + ASPEED_PECI_INT_STS) | > > ASPEED_PECI_INT_MASK; > > + writel(val, priv->base + ASPEED_PECI_INT_STS); > > + > > + /* Set timing negotiation mode and enable interrupts */ > > + val = FIELD_PREP(ASPEED_PECI_TIMING_NEGO_SEL_MASK, > > ASPEED_PECI_1ST_BIT_OF_ADDR_NEGO); > > + val |= ASPEED_PECI_INT_MASK; > > + writel(val, priv->base + ASPEED_PECI_INT_CTRL); > > + > > + val = FIELD_PREP(ASPEED_PECI_CTRL_SAMPLING_MASK, priv- > > >rd_sampling_point); > > + val |= FIELD_PREP(ASPEED_PECI_CTRL_CLK_DIV_MASK, priv->clk_div); > > + val |= ASPEED_PECI_CTRL_PECI_EN; > > + val |= ASPEED_PECI_CTRL_PECI_CLK_EN; > > + writel(val, priv->base + ASPEED_PECI_CTRL); > > +} > > + > > +static inline int aspeed_peci_check_idle(struct aspeed_peci *priv) > > +{ > > + u32 cmd_sts = readl(priv->base + ASPEED_PECI_CMD); > > + > > + if (FIELD_GET(ASPEED_PECI_CMD_STS_MASK, cmd_sts) == > > ASPEED_PECI_CMD_STS_ADDR_T_NEGO) > > + aspeed_peci_init_regs(priv); > > + > > + return readl_poll_timeout(priv->base + ASPEED_PECI_CMD, > > + cmd_sts, > > + !(cmd_sts & ASPEED_PECI_CMD_IDLE_MASK), > > + ASPEED_PECI_IDLE_CHECK_INTERVAL_US, > > + ASPEED_PECI_IDLE_CHECK_TIMEOUT_US); > > +} > > + > > +static int aspeed_peci_xfer(struct peci_controller *controller, > > + u8 addr, struct peci_request *req) > > +{ > > + struct aspeed_peci *priv = dev_get_drvdata(controller->dev.parent); > > + unsigned long flags, timeout = msecs_to_jiffies(priv- > > >cmd_timeout_ms); > > + u32 peci_head; > > + int ret; > > + > > + if (req->tx.len > ASPEED_PECI_DATA_BUF_SIZE_MAX || > > + req->rx.len > ASPEED_PECI_DATA_BUF_SIZE_MAX) > > + return -EINVAL; > > + > > + /* Check command sts and bus idle state */ > > + ret = aspeed_peci_check_idle(priv); > > + if (ret) > > + return ret; /* -ETIMEDOUT */ > > + > > + spin_lock_irqsave(&priv->lock, flags); > > + reinit_completion(&priv->xfer_complete); > > + > > + peci_head = FIELD_PREP(ASPEED_PECI_TARGET_ADDR_MASK, addr) | > > + FIELD_PREP(ASPEED_PECI_WR_LEN_MASK, req->tx.len) | > > + FIELD_PREP(ASPEED_PECI_RD_LEN_MASK, req->rx.len); > > + > > + writel(peci_head, priv->base + ASPEED_PECI_RW_LENGTH); > > + > > + memcpy_toio(priv->base + ASPEED_PECI_WR_DATA0, req->tx.buf, > > min_t(u8, req->tx.len, 16)); > > + if (req->tx.len > 16) > > + memcpy_toio(priv->base + ASPEED_PECI_WR_DATA4, req->tx.buf + > > 16, > > + req->tx.len - 16); > > + > > + dev_dbg(priv->dev, "HEAD : 0x%08x\n", peci_head); > > + print_hex_dump_bytes("TX : ", DUMP_PREFIX_NONE, req->tx.buf, req- > > >tx.len); > > On CONFIG_DYNAMIC_DEBUG=n builds the kernel will do all the work of > reading through this buffer, but skip emitting it. Are you sure you > want to pay that overhead for every transaction? I can remove it or I can add something like: #if IS_ENABLED(CONFIG_PECI_DEBUG) #define peci_debug(fmt, ...) pr_debug(fmt, ##__VA_ARGS__) #else #define peci_debug(...) do { } while (0) #endif (and similar peci_trace with trace_printk for usage in IRQ handlers and such). What do you think? > > > + > > + priv->status = 0; > > + writel(ASPEED_PECI_CMD_FIRE, priv->base + ASPEED_PECI_CMD); > > + spin_unlock_irqrestore(&priv->lock, flags); > > + > > + ret = wait_for_completion_interruptible_timeout(&priv- > > >xfer_complete, timeout); > > spin_lock_irqsave() says "I don't know if interrupts are disabled > already, so I'll save the state, whatever it is, and restore later" > > wait_for_completion_interruptible_timeout() says "I know I am in a > sleepable context where interrupts are enabled" > > So, one of those is wrong, i.e. should it be spin_{lock,unlock}_irq()? You're right - I'll fix it. > > > > + if (ret < 0) > > + return ret; > > + > > + if (ret == 0) { > > + dev_dbg(priv->dev, "Timeout waiting for a response!\n"); > > + return -ETIMEDOUT; > > + } > > + > > + spin_lock_irqsave(&priv->lock, flags); > > + > > + writel(0, priv->base + ASPEED_PECI_CMD); > > + > > + if (priv->status != ASPEED_PECI_INT_CMD_DONE) { > > + spin_unlock_irqrestore(&priv->lock, flags); > > + dev_dbg(priv->dev, "No valid response!\n"); > > + return -EIO; > > + } > > + > > + spin_unlock_irqrestore(&priv->lock, flags); > > + > > + memcpy_fromio(req->rx.buf, priv->base + ASPEED_PECI_RD_DATA0, > > min_t(u8, req->rx.len, 16)); > > + if (req->rx.len > 16) > > + memcpy_fromio(req->rx.buf + 16, priv->base + > > ASPEED_PECI_RD_DATA4, > > + req->rx.len - 16); > > + > > + print_hex_dump_bytes("RX : ", DUMP_PREFIX_NONE, req->rx.buf, req- > > >rx.len); > > + > > + return 0; > > +} > > + > > +static irqreturn_t aspeed_peci_irq_handler(int irq, void *arg) > > +{ > > + struct aspeed_peci *priv = arg; > > + u32 status; > > + > > + spin_lock(&priv->lock); > > + status = readl(priv->base + ASPEED_PECI_INT_STS); > > + writel(status, priv->base + ASPEED_PECI_INT_STS); > > + priv->status |= (status & ASPEED_PECI_INT_MASK); > > + > > + /* > > + * In most cases, interrupt bits will be set one by one but also > > note > > + * that multiple interrupt bits could be set at the same time. > > + */ > > + if (status & ASPEED_PECI_INT_BUS_TIMEOUT) > > + dev_dbg_ratelimited(priv->dev, > > "ASPEED_PECI_INT_BUS_TIMEOUT\n"); > > + > > + if (status & ASPEED_PECI_INT_BUS_CONTENTION) > > + dev_dbg_ratelimited(priv->dev, > > "ASPEED_PECI_INT_BUS_CONTENTION\n"); > > + > > + if (status & ASPEED_PECI_INT_WR_FCS_BAD) > > + dev_dbg_ratelimited(priv->dev, > > "ASPEED_PECI_INT_WR_FCS_BAD\n"); > > + > > + if (status & ASPEED_PECI_INT_WR_FCS_ABORT) > > + dev_dbg_ratelimited(priv->dev, > > "ASPEED_PECI_INT_WR_FCS_ABORT\n"); > > Are you sure these would not be better as tracepoints? If you're > debugging an interrupt related failure, the ratelimiting might get in > your way when you really need to know when one of these error > interrupts fire relative to another event. Tracepoints are ABI(ish), and using a full blown tracepoint just for IRQ status would probably be too much. I was thinking about something like trace_printk hidden under a "CONFIG_PECI_DEBUG" (see above), but perhaps that's something for the future improvement? > > > + > > + /* > > + * All commands should be ended up with a ASPEED_PECI_INT_CMD_DONE > > bit > > + * set even in an error case. > > + */ > > + if (status & ASPEED_PECI_INT_CMD_DONE) > > + complete(&priv->xfer_complete); > > Hmm, no need to check if there was a sequencing error, like a command > was never submitted? It's handled by checking if HW is idle in xfer before a command is sent, where we just expect a single interrupt per command. > > > + > > + spin_unlock(&priv->lock); > > + > > + return IRQ_HANDLED; > > +} > > + > > +static void aspeed_peci_property_sanitize(struct device *dev, const char > > *propname, > > + u32 min, u32 max, u32 default_val, > > u32 *propval) > > +{ > > + u32 val; > > + int ret; > > + > > + ret = device_property_read_u32(dev, propname, &val); > > + if (ret) { > > + val = default_val; > > + } else if (val > max || val < min) { > > + dev_warn(dev, "Invalid %s: %u, falling back to: %u\n", > > + propname, val, default_val); > > + > > + val = default_val; > > + } > > + > > + *propval = val; > > +} > > + > > +static void aspeed_peci_property_setup(struct aspeed_peci *priv) > > +{ > > + aspeed_peci_property_sanitize(priv->dev, "aspeed,clock-divider", > > + 0, ASPEED_PECI_CLK_DIV_MAX, > > + ASPEED_PECI_CLK_DIV_DEFAULT, &priv- > > >clk_div); > > + aspeed_peci_property_sanitize(priv->dev, "aspeed,msg-timing", > > + 0, ASPEED_PECI_MSG_TIMING_MAX, > > + ASPEED_PECI_MSG_TIMING_DEFAULT, &priv- > > >msg_timing); > > + aspeed_peci_property_sanitize(priv->dev, "aspeed,addr-timing", > > + 0, ASPEED_PECI_ADDR_TIMING_MAX, > > + ASPEED_PECI_ADDR_TIMING_DEFAULT, > > &priv->addr_timing); > > + aspeed_peci_property_sanitize(priv->dev, "aspeed,rd-sampling-point", > > + 0, ASPEED_PECI_RD_SAMPLING_POINT_MAX, > > + ASPEED_PECI_RD_SAMPLING_POINT_DEFAULT, > > + &priv->rd_sampling_point); > > + aspeed_peci_property_sanitize(priv->dev, "cmd-timeout-ms", > > + 1, ASPEED_PECI_CMD_TIMEOUT_MS_MAX, > > + ASPEED_PECI_CMD_TIMEOUT_MS_DEFAULT, > > &priv->cmd_timeout_ms); > > +} > > + > > +static struct peci_controller_ops aspeed_ops = { > > + .xfer = aspeed_peci_xfer, > > +}; > > + > > +static void aspeed_peci_reset_control_release(void *data) > > +{ > > + reset_control_assert(data); > > +} > > + > > +int aspeed_peci_reset_control_deassert(struct device *dev, struct > > reset_control *rst) > > I'd recommend naming this devm_aspeed_peci_reset_control_deassert(), > because I came looking here from reading probe for why there was no > reassertion of reset on driver ->remove(). Ok. > > > +{ > > + int ret; > > + > > + ret = reset_control_deassert(rst); > > + if (ret) > > + return ret; > > + > > + return devm_add_action_or_reset(dev, > > aspeed_peci_reset_control_release, rst); > > +} > > + > > +static void aspeed_peci_clk_release(void *data) > > +{ > > + clk_disable_unprepare(data); > > +} > > + > > +static int aspeed_peci_clk_enable(struct device *dev, struct clk *clk) > > ...ditto on the devm prefix, just to speed readability. Ok. Thanks -Iwona > > > +{ > > + int ret; > > + > > + ret = clk_prepare_enable(clk); > > + if (ret) > > + return ret; > > + > > + return devm_add_action_or_reset(dev, aspeed_peci_clk_release, clk); > > +} > > + > > +static int aspeed_peci_probe(struct platform_device *pdev) > > +{ > > + struct peci_controller *controller; > > + struct aspeed_peci *priv; > > + int ret; > > + > > + priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); > > + if (!priv) > > + return -ENOMEM; > > + > > + priv->dev = &pdev->dev; > > + dev_set_drvdata(priv->dev, priv); > > + > > + priv->base = devm_platform_ioremap_resource(pdev, 0); > > + if (IS_ERR(priv->base)) > > + return PTR_ERR(priv->base); > > + > > + priv->irq = platform_get_irq(pdev, 0); > > + if (!priv->irq) > > + return priv->irq; > > + > > + ret = devm_request_irq(&pdev->dev, priv->irq, > > aspeed_peci_irq_handler, > > + 0, "peci-aspeed", priv); > > + if (ret) > > + return ret; > > + > > + init_completion(&priv->xfer_complete); > > + spin_lock_init(&priv->lock); > > + > > + priv->rst = devm_reset_control_get(&pdev->dev, NULL); > > + if (IS_ERR(priv->rst)) > > + return dev_err_probe(priv->dev, PTR_ERR(priv->rst), > > + "failed to get reset control\n"); > > + > > + ret = aspeed_peci_reset_control_deassert(priv->dev, priv->rst); > > + if (ret) > > + return dev_err_probe(priv->dev, ret, "cannot deassert reset > > control\n"); > > + > > + priv->clk = devm_clk_get(priv->dev, NULL); > > + if (IS_ERR(priv->clk)) > > + return dev_err_probe(priv->dev, PTR_ERR(priv->clk), "failed > > to get clk\n"); > > + > > + ret = aspeed_peci_clk_enable(priv->dev, priv->clk); > > + if (ret) > > + return dev_err_probe(priv->dev, ret, "failed to enable > > clock\n"); > > + > > + aspeed_peci_property_setup(priv); > > + > > + aspeed_peci_init_regs(priv); > > + > > + controller = devm_peci_controller_add(priv->dev, &aspeed_ops); > > + if (IS_ERR(controller)) > > + return dev_err_probe(priv->dev, PTR_ERR(controller), > > + "failed to add aspeed peci > > controller\n"); > > + > > + priv->controller = controller; > > + > > + return 0; > > +} > > + > > +static const struct of_device_id aspeed_peci_of_table[] = { > > + { .compatible = "aspeed,ast2400-peci", }, > > + { .compatible = "aspeed,ast2500-peci", }, > > + { .compatible = "aspeed,ast2600-peci", }, > > + { } > > +}; > > +MODULE_DEVICE_TABLE(of, aspeed_peci_of_table); > > + > > +static struct platform_driver aspeed_peci_driver = { > > + .probe = aspeed_peci_probe, > > + .driver = { > > + .name = "peci-aspeed", > > + .of_match_table = aspeed_peci_of_table, > > + }, > > +}; > > +module_platform_driver(aspeed_peci_driver); > > + > > +MODULE_AUTHOR("Ryan Chen <ryan_chen@aspeedtech.com>"); > > +MODULE_AUTHOR("Jae Hyun Yoo <jae.hyun.yoo@linux.intel.com>"); > > +MODULE_DESCRIPTION("ASPEED PECI driver"); > > +MODULE_LICENSE("GPL"); > > +MODULE_IMPORT_NS(PECI); > > -- > > 2.31.1 > >
On Thu, Aug 26, 2021 at 4:55 PM Winiarska, Iwona <iwona.winiarska@intel.com> wrote: > > On Wed, 2021-08-25 at 18:35 -0700, Dan Williams wrote: > > On Tue, Aug 3, 2021 at 4:35 AM Iwona Winiarska > > <iwona.winiarska@intel.com> wrote: > > > > > > From: Jae Hyun Yoo <jae.hyun.yoo@linux.intel.com> > > > > > > ASPEED AST24xx/AST25xx/AST26xx SoCs supports the PECI electrical > > > interface (a.k.a PECI wire). > > > > Maybe a one sentence blurb here and in the Kconfig reminding people > > why they should care if they have a PECI driver or not? > > Ok, I'll expand it a bit. [..] > > > +static int aspeed_peci_xfer(struct peci_controller *controller, > > > + u8 addr, struct peci_request *req) > > > +{ > > > + struct aspeed_peci *priv = dev_get_drvdata(controller->dev.parent); > > > + unsigned long flags, timeout = msecs_to_jiffies(priv- > > > >cmd_timeout_ms); > > > + u32 peci_head; > > > + int ret; > > > + > > > + if (req->tx.len > ASPEED_PECI_DATA_BUF_SIZE_MAX || > > > + req->rx.len > ASPEED_PECI_DATA_BUF_SIZE_MAX) > > > + return -EINVAL; > > > + > > > + /* Check command sts and bus idle state */ > > > + ret = aspeed_peci_check_idle(priv); > > > + if (ret) > > > + return ret; /* -ETIMEDOUT */ > > > + > > > + spin_lock_irqsave(&priv->lock, flags); > > > + reinit_completion(&priv->xfer_complete); > > > + > > > + peci_head = FIELD_PREP(ASPEED_PECI_TARGET_ADDR_MASK, addr) | > > > + FIELD_PREP(ASPEED_PECI_WR_LEN_MASK, req->tx.len) | > > > + FIELD_PREP(ASPEED_PECI_RD_LEN_MASK, req->rx.len); > > > + > > > + writel(peci_head, priv->base + ASPEED_PECI_RW_LENGTH); > > > + > > > + memcpy_toio(priv->base + ASPEED_PECI_WR_DATA0, req->tx.buf, > > > min_t(u8, req->tx.len, 16)); > > > + if (req->tx.len > 16) > > > + memcpy_toio(priv->base + ASPEED_PECI_WR_DATA4, req->tx.buf + > > > 16, > > > + req->tx.len - 16); > > > + > > > + dev_dbg(priv->dev, "HEAD : 0x%08x\n", peci_head); > > > + print_hex_dump_bytes("TX : ", DUMP_PREFIX_NONE, req->tx.buf, req- > > > >tx.len); > > > > On CONFIG_DYNAMIC_DEBUG=n builds the kernel will do all the work of > > reading through this buffer, but skip emitting it. Are you sure you > > want to pay that overhead for every transaction? > > I can remove it or I can add something like: > > #if IS_ENABLED(CONFIG_PECI_DEBUG) > #define peci_debug(fmt, ...) pr_debug(fmt, ##__VA_ARGS__) > #else > #define peci_debug(...) do { } while (0) > #endif It's the hex dump I'm worried about, not the debug statements as much. I think the choices are remove the print_hex_dump_bytes(), put it behind an IS_ENABLED(CONFIG_DYNAMIC_DEBUG) to ensure the overhead is skipped in the CONFIG_DYNAMIC_DEBUG=n case, or live with the overhead if this is not a fast path / infrequently used. > > (and similar peci_trace with trace_printk for usage in IRQ handlers and such). > > What do you think? In general, no, don't wrap the base level print routines with driver-specific ones. Also, trace_printk() is only for debug builds. Note that trace points are built to be even less overhead than dev_dbg(), so there's no overhead concern with disabled tracepoints, they literally translate to nops when disabled. > > > > > > + > > > + priv->status = 0; > > > + writel(ASPEED_PECI_CMD_FIRE, priv->base + ASPEED_PECI_CMD); > > > + spin_unlock_irqrestore(&priv->lock, flags); > > > + > > > + ret = wait_for_completion_interruptible_timeout(&priv- > > > >xfer_complete, timeout); > > > > spin_lock_irqsave() says "I don't know if interrupts are disabled > > already, so I'll save the state, whatever it is, and restore later" > > > > wait_for_completion_interruptible_timeout() says "I know I am in a > > sleepable context where interrupts are enabled" > > > > So, one of those is wrong, i.e. should it be spin_{lock,unlock}_irq()? > > You're right - I'll fix it. > > > > > > > > + if (ret < 0) > > > + return ret; > > > + > > > + if (ret == 0) { > > > + dev_dbg(priv->dev, "Timeout waiting for a response!\n"); > > > + return -ETIMEDOUT; > > > + } > > > + > > > + spin_lock_irqsave(&priv->lock, flags); > > > + > > > + writel(0, priv->base + ASPEED_PECI_CMD); > > > + > > > + if (priv->status != ASPEED_PECI_INT_CMD_DONE) { > > > + spin_unlock_irqrestore(&priv->lock, flags); > > > + dev_dbg(priv->dev, "No valid response!\n"); > > > + return -EIO; > > > + } > > > + > > > + spin_unlock_irqrestore(&priv->lock, flags); > > > + > > > + memcpy_fromio(req->rx.buf, priv->base + ASPEED_PECI_RD_DATA0, > > > min_t(u8, req->rx.len, 16)); > > > + if (req->rx.len > 16) > > > + memcpy_fromio(req->rx.buf + 16, priv->base + > > > ASPEED_PECI_RD_DATA4, > > > + req->rx.len - 16); > > > + > > > + print_hex_dump_bytes("RX : ", DUMP_PREFIX_NONE, req->rx.buf, req- > > > >rx.len); > > > + > > > + return 0; > > > +} > > > + > > > +static irqreturn_t aspeed_peci_irq_handler(int irq, void *arg) > > > +{ > > > + struct aspeed_peci *priv = arg; > > > + u32 status; > > > + > > > + spin_lock(&priv->lock); > > > + status = readl(priv->base + ASPEED_PECI_INT_STS); > > > + writel(status, priv->base + ASPEED_PECI_INT_STS); > > > + priv->status |= (status & ASPEED_PECI_INT_MASK); > > > + > > > + /* > > > + * In most cases, interrupt bits will be set one by one but also > > > note > > > + * that multiple interrupt bits could be set at the same time. > > > + */ > > > + if (status & ASPEED_PECI_INT_BUS_TIMEOUT) > > > + dev_dbg_ratelimited(priv->dev, > > > "ASPEED_PECI_INT_BUS_TIMEOUT\n"); > > > + > > > + if (status & ASPEED_PECI_INT_BUS_CONTENTION) > > > + dev_dbg_ratelimited(priv->dev, > > > "ASPEED_PECI_INT_BUS_CONTENTION\n"); > > > + > > > + if (status & ASPEED_PECI_INT_WR_FCS_BAD) > > > + dev_dbg_ratelimited(priv->dev, > > > "ASPEED_PECI_INT_WR_FCS_BAD\n"); > > > + > > > + if (status & ASPEED_PECI_INT_WR_FCS_ABORT) > > > + dev_dbg_ratelimited(priv->dev, > > > "ASPEED_PECI_INT_WR_FCS_ABORT\n"); > > > > Are you sure these would not be better as tracepoints? If you're > > debugging an interrupt related failure, the ratelimiting might get in > > your way when you really need to know when one of these error > > interrupts fire relative to another event. > > Tracepoints are ABI(ish), and using a full blown tracepoint just for IRQ status > would probably be too much. Tracepoints become ABI once someone ships tooling that depends on them being there. These don't look attractive for a tool, and they don't look difficult to maintain if the interrupt handler needs to be reworked. I.e. it would be trivial to keep a dead tracepoint around if worse came to worse to keep a tool from failing to load. > I was thinking about something like trace_printk hidden under a > "CONFIG_PECI_DEBUG" (see above), but perhaps that's something for the future > improvement? Again trace_printk() is only for private builds. > > > > > > + > > > + /* > > > + * All commands should be ended up with a ASPEED_PECI_INT_CMD_DONE > > > bit > > > + * set even in an error case. > > > + */ > > > + if (status & ASPEED_PECI_INT_CMD_DONE) > > > + complete(&priv->xfer_complete); > > > > Hmm, no need to check if there was a sequencing error, like a command > > was never submitted? > > It's handled by checking if HW is idle in xfer before a command is sent, where > we just expect a single interrupt per command. I'm asking how do you determine if this status was spurious, or there was a sequencing error in the driver?
On Fri, 2021-08-27 at 09:24 -0700, Dan Williams wrote: > On Thu, Aug 26, 2021 at 4:55 PM Winiarska, Iwona > <iwona.winiarska@intel.com> wrote: > > > > On Wed, 2021-08-25 at 18:35 -0700, Dan Williams wrote: > > > On Tue, Aug 3, 2021 at 4:35 AM Iwona Winiarska > > > <iwona.winiarska@intel.com> wrote: > > > > > > > > From: Jae Hyun Yoo <jae.hyun.yoo@linux.intel.com> > > > > > > > > ASPEED AST24xx/AST25xx/AST26xx SoCs supports the PECI electrical > > > > interface (a.k.a PECI wire). > > > > > > Maybe a one sentence blurb here and in the Kconfig reminding people > > > why they should care if they have a PECI driver or not? > > > > Ok, I'll expand it a bit. > [..] > > > > +static int aspeed_peci_xfer(struct peci_controller *controller, > > > > + u8 addr, struct peci_request *req) > > > > +{ > > > > + struct aspeed_peci *priv = dev_get_drvdata(controller- > > > > >dev.parent); > > > > + unsigned long flags, timeout = msecs_to_jiffies(priv- > > > > > cmd_timeout_ms); > > > > + u32 peci_head; > > > > + int ret; > > > > + > > > > + if (req->tx.len > ASPEED_PECI_DATA_BUF_SIZE_MAX || > > > > + req->rx.len > ASPEED_PECI_DATA_BUF_SIZE_MAX) > > > > + return -EINVAL; > > > > + > > > > + /* Check command sts and bus idle state */ > > > > + ret = aspeed_peci_check_idle(priv); > > > > + if (ret) > > > > + return ret; /* -ETIMEDOUT */ > > > > + > > > > + spin_lock_irqsave(&priv->lock, flags); > > > > + reinit_completion(&priv->xfer_complete); > > > > + > > > > + peci_head = FIELD_PREP(ASPEED_PECI_TARGET_ADDR_MASK, addr) | > > > > + FIELD_PREP(ASPEED_PECI_WR_LEN_MASK, req->tx.len) | > > > > + FIELD_PREP(ASPEED_PECI_RD_LEN_MASK, req->rx.len); > > > > + > > > > + writel(peci_head, priv->base + ASPEED_PECI_RW_LENGTH); > > > > + > > > > + memcpy_toio(priv->base + ASPEED_PECI_WR_DATA0, req->tx.buf, > > > > min_t(u8, req->tx.len, 16)); > > > > + if (req->tx.len > 16) > > > > + memcpy_toio(priv->base + ASPEED_PECI_WR_DATA4, req- > > > > >tx.buf + > > > > 16, > > > > + req->tx.len - 16); > > > > + > > > > + dev_dbg(priv->dev, "HEAD : 0x%08x\n", peci_head); > > > > + print_hex_dump_bytes("TX : ", DUMP_PREFIX_NONE, req->tx.buf, > > > > req- > > > > > tx.len); > > > > > > On CONFIG_DYNAMIC_DEBUG=n builds the kernel will do all the work of > > > reading through this buffer, but skip emitting it. Are you sure you > > > want to pay that overhead for every transaction? > > > > I can remove it or I can add something like: > > > > #if IS_ENABLED(CONFIG_PECI_DEBUG) > > #define peci_debug(fmt, ...) pr_debug(fmt, ##__VA_ARGS__) > > #else > > #define peci_debug(...) do { } while (0) > > #endif > > It's the hex dump I'm worried about, not the debug statements as much. > > I think the choices are remove the print_hex_dump_bytes(), put it > behind an IS_ENABLED(CONFIG_DYNAMIC_DEBUG) to ensure the overhead is > skipped in the CONFIG_DYNAMIC_DEBUG=n case, or live with the overhead > if this is not a fast path / infrequently used. I will place it behind IS_ENABLED(CONFIG_DYNAMIC_DEBUG). > > > > > (and similar peci_trace with trace_printk for usage in IRQ handlers and > > such). > > > > What do you think? > > In general, no, don't wrap the base level print routines with > driver-specific ones. Also, trace_printk() is only for debug builds. > Note that trace points are built to be even less overhead than > dev_dbg(), so there's no overhead concern with disabled tracepoints, > they literally translate to nops when disabled. Ack. > > > > > > > > > > + > > > > + priv->status = 0; > > > > + writel(ASPEED_PECI_CMD_FIRE, priv->base + ASPEED_PECI_CMD); > > > > + spin_unlock_irqrestore(&priv->lock, flags); > > > > + > > > > + ret = wait_for_completion_interruptible_timeout(&priv- > > > > > xfer_complete, timeout); > > > > > > spin_lock_irqsave() says "I don't know if interrupts are disabled > > > already, so I'll save the state, whatever it is, and restore later" > > > > > > wait_for_completion_interruptible_timeout() says "I know I am in a > > > sleepable context where interrupts are enabled" > > > > > > So, one of those is wrong, i.e. should it be spin_{lock,unlock}_irq()? > > > > You're right - I'll fix it. > > > > > > > > > > > > + if (ret < 0) > > > > + return ret; > > > > + > > > > + if (ret == 0) { > > > > + dev_dbg(priv->dev, "Timeout waiting for a response!\n"); > > > > + return -ETIMEDOUT; > > > > + } > > > > + > > > > + spin_lock_irqsave(&priv->lock, flags); > > > > + > > > > + writel(0, priv->base + ASPEED_PECI_CMD); > > > > + > > > > + if (priv->status != ASPEED_PECI_INT_CMD_DONE) { > > > > + spin_unlock_irqrestore(&priv->lock, flags); > > > > + dev_dbg(priv->dev, "No valid response!\n"); > > > > + return -EIO; > > > > + } > > > > + > > > > + spin_unlock_irqrestore(&priv->lock, flags); > > > > + > > > > + memcpy_fromio(req->rx.buf, priv->base + ASPEED_PECI_RD_DATA0, > > > > min_t(u8, req->rx.len, 16)); > > > > + if (req->rx.len > 16) > > > > + memcpy_fromio(req->rx.buf + 16, priv->base + > > > > ASPEED_PECI_RD_DATA4, > > > > + req->rx.len - 16); > > > > + > > > > + print_hex_dump_bytes("RX : ", DUMP_PREFIX_NONE, req->rx.buf, > > > > req- > > > > > rx.len); > > > > + > > > > + return 0; > > > > +} > > > > + > > > > +static irqreturn_t aspeed_peci_irq_handler(int irq, void *arg) > > > > +{ > > > > + struct aspeed_peci *priv = arg; > > > > + u32 status; > > > > + > > > > + spin_lock(&priv->lock); > > > > + status = readl(priv->base + ASPEED_PECI_INT_STS); > > > > + writel(status, priv->base + ASPEED_PECI_INT_STS); > > > > + priv->status |= (status & ASPEED_PECI_INT_MASK); > > > > + > > > > + /* > > > > + * In most cases, interrupt bits will be set one by one but also > > > > note > > > > + * that multiple interrupt bits could be set at the same time. > > > > + */ > > > > + if (status & ASPEED_PECI_INT_BUS_TIMEOUT) > > > > + dev_dbg_ratelimited(priv->dev, > > > > "ASPEED_PECI_INT_BUS_TIMEOUT\n"); > > > > + > > > > + if (status & ASPEED_PECI_INT_BUS_CONTENTION) > > > > + dev_dbg_ratelimited(priv->dev, > > > > "ASPEED_PECI_INT_BUS_CONTENTION\n"); > > > > + > > > > + if (status & ASPEED_PECI_INT_WR_FCS_BAD) > > > > + dev_dbg_ratelimited(priv->dev, > > > > "ASPEED_PECI_INT_WR_FCS_BAD\n"); > > > > + > > > > + if (status & ASPEED_PECI_INT_WR_FCS_ABORT) > > > > + dev_dbg_ratelimited(priv->dev, > > > > "ASPEED_PECI_INT_WR_FCS_ABORT\n"); > > > > > > Are you sure these would not be better as tracepoints? If you're > > > debugging an interrupt related failure, the ratelimiting might get in > > > your way when you really need to know when one of these error > > > interrupts fire relative to another event. > > > > Tracepoints are ABI(ish), and using a full blown tracepoint just for IRQ > > status > > would probably be too much. > > Tracepoints become ABI once someone ships tooling that depends on them > being there. These don't look attractive for a tool, and they don't > look difficult to maintain if the interrupt handler needs to be > reworked. I.e. it would be trivial to keep a dead tracepoint around if > worse came to worse to keep a tool from failing to load. After more consideration, I would prefer to remove these logs for now - in case of error I'll log full status in xfer(). > > > I was thinking about something like trace_printk hidden under a > > "CONFIG_PECI_DEBUG" (see above), but perhaps that's something for the future > > improvement? > > Again trace_printk() is only for private builds. > > > > > > > > > > + > > > > + /* > > > > + * All commands should be ended up with a > > > > ASPEED_PECI_INT_CMD_DONE > > > > bit > > > > + * set even in an error case. > > > > + */ > > > > + if (status & ASPEED_PECI_INT_CMD_DONE) > > > > + complete(&priv->xfer_complete); > > > > > > Hmm, no need to check if there was a sequencing error, like a command > > > was never submitted? > > > > It's handled by checking if HW is idle in xfer before a command is sent, > > where > > we just expect a single interrupt per command. > > I'm asking how do you determine if this status was spurious, or there > was a sequencing error in the driver? I don't think we have any means to determine it. PECI itself doesn't provide any mechanism to verify it (there is no sequence number or tag to match request/response). We're relying on the fact that BMC is a requester and initiates communication with CPU - the interrupt won't be generated if BMC doesn't send any request. Thanks -Iwona
diff --git a/MAINTAINERS b/MAINTAINERS index d411974aaa5e..6e9d53ff68ab 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -2866,6 +2866,15 @@ S: Maintained F: Documentation/hwmon/asc7621.rst F: drivers/hwmon/asc7621.c +ASPEED PECI CONTROLLER +M: Iwona Winiarska <iwona.winiarska@intel.com> +M: Jae Hyun Yoo <jae.hyun.yoo@linux.intel.com> +L: linux-aspeed@lists.ozlabs.org (moderated for non-subscribers) +L: openbmc@lists.ozlabs.org (moderated for non-subscribers) +S: Supported +F: Documentation/devicetree/bindings/peci/peci-aspeed.yaml +F: drivers/peci/controller/peci-aspeed.c + ASPEED PINCTRL DRIVERS M: Andrew Jeffery <andrew@aj.id.au> L: linux-aspeed@lists.ozlabs.org (moderated for non-subscribers) diff --git a/drivers/peci/Kconfig b/drivers/peci/Kconfig index 71a4ad81225a..99279df97a78 100644 --- a/drivers/peci/Kconfig +++ b/drivers/peci/Kconfig @@ -13,3 +13,9 @@ menuconfig PECI This support is also available as a module. If so, the module will be called peci. + +if PECI + +source "drivers/peci/controller/Kconfig" + +endif # PECI diff --git a/drivers/peci/Makefile b/drivers/peci/Makefile index e789a354e842..926d8df15cbd 100644 --- a/drivers/peci/Makefile +++ b/drivers/peci/Makefile @@ -3,3 +3,6 @@ # Core functionality peci-y := core.o obj-$(CONFIG_PECI) += peci.o + +# Hardware specific bus drivers +obj-y += controller/ diff --git a/drivers/peci/controller/Kconfig b/drivers/peci/controller/Kconfig new file mode 100644 index 000000000000..6d48df08db1c --- /dev/null +++ b/drivers/peci/controller/Kconfig @@ -0,0 +1,16 @@ +# SPDX-License-Identifier: GPL-2.0-only + +config PECI_ASPEED + tristate "ASPEED PECI support" + depends on ARCH_ASPEED || COMPILE_TEST + depends on OF + depends on HAS_IOMEM + help + This option enables PECI controller driver for ASPEED AST2400, + AST2500 and AST2600 SoCs. + + Say Y here if your system runs on ASPEED SoC and you are using it + as BMC for Intel platform. + + This driver can also be built as a module. If so, the module will + be called peci-aspeed. diff --git a/drivers/peci/controller/Makefile b/drivers/peci/controller/Makefile new file mode 100644 index 000000000000..022c28ef1bf0 --- /dev/null +++ b/drivers/peci/controller/Makefile @@ -0,0 +1,3 @@ +# SPDX-License-Identifier: GPL-2.0-only + +obj-$(CONFIG_PECI_ASPEED) += peci-aspeed.o diff --git a/drivers/peci/controller/peci-aspeed.c b/drivers/peci/controller/peci-aspeed.c new file mode 100644 index 000000000000..1d708c983749 --- /dev/null +++ b/drivers/peci/controller/peci-aspeed.c @@ -0,0 +1,445 @@ +// SPDX-License-Identifier: GPL-2.0-only +// Copyright (C) 2012-2017 ASPEED Technology Inc. +// Copyright (c) 2018-2021 Intel Corporation + +#include <linux/bitfield.h> +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/iopoll.h> +#include <linux/jiffies.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/peci.h> +#include <linux/platform_device.h> +#include <linux/reset.h> + +#include <asm/unaligned.h> + +/* ASPEED PECI Registers */ +/* Control Register */ +#define ASPEED_PECI_CTRL 0x00 +#define ASPEED_PECI_CTRL_SAMPLING_MASK GENMASK(19, 16) +#define ASPEED_PECI_CTRL_RD_MODE_MASK GENMASK(13, 12) +#define ASPEED_PECI_CTRL_RD_MODE_DBG BIT(13) +#define ASPEED_PECI_CTRL_RD_MODE_COUNT BIT(12) +#define ASPEED_PECI_CTRL_CLK_SOURCE BIT(11) +#define ASPEED_PECI_CTRL_CLK_DIV_MASK GENMASK(10, 8) +#define ASPEED_PECI_CTRL_INVERT_OUT BIT(7) +#define ASPEED_PECI_CTRL_INVERT_IN BIT(6) +#define ASPEED_PECI_CTRL_BUS_CONTENTION_EN BIT(5) +#define ASPEED_PECI_CTRL_PECI_EN BIT(4) +#define ASPEED_PECI_CTRL_PECI_CLK_EN BIT(0) + +/* Timing Negotiation Register */ +#define ASPEED_PECI_TIMING_NEGOTIATION 0x04 +#define ASPEED_PECI_T_NEGO_MSG_MASK GENMASK(15, 8) +#define ASPEED_PECI_T_NEGO_ADDR_MASK GENMASK(7, 0) + +/* Command Register */ +#define ASPEED_PECI_CMD 0x08 +#define ASPEED_PECI_CMD_PIN_MONITORING BIT(31) +#define ASPEED_PECI_CMD_STS_MASK GENMASK(27, 24) +#define ASPEED_PECI_CMD_STS_ADDR_T_NEGO 0x3 +#define ASPEED_PECI_CMD_IDLE_MASK \ + (ASPEED_PECI_CMD_STS_MASK | ASPEED_PECI_CMD_PIN_MONITORING) +#define ASPEED_PECI_CMD_FIRE BIT(0) + +/* Read/Write Length Register */ +#define ASPEED_PECI_RW_LENGTH 0x0c +#define ASPEED_PECI_AW_FCS_EN BIT(31) +#define ASPEED_PECI_RD_LEN_MASK GENMASK(23, 16) +#define ASPEED_PECI_WR_LEN_MASK GENMASK(15, 8) +#define ASPEED_PECI_TARGET_ADDR_MASK GENMASK(7, 0) + +/* Expected FCS Data Register */ +#define ASPEED_PECI_EXPECTED_FCS 0x10 +#define ASPEED_PECI_EXPECTED_RD_FCS_MASK GENMASK(23, 16) +#define ASPEED_PECI_EXPECTED_AW_FCS_AUTO_MASK GENMASK(15, 8) +#define ASPEED_PECI_EXPECTED_WR_FCS_MASK GENMASK(7, 0) + +/* Captured FCS Data Register */ +#define ASPEED_PECI_CAPTURED_FCS 0x14 +#define ASPEED_PECI_CAPTURED_RD_FCS_MASK GENMASK(23, 16) +#define ASPEED_PECI_CAPTURED_WR_FCS_MASK GENMASK(7, 0) + +/* Interrupt Register */ +#define ASPEED_PECI_INT_CTRL 0x18 +#define ASPEED_PECI_TIMING_NEGO_SEL_MASK GENMASK(31, 30) +#define ASPEED_PECI_1ST_BIT_OF_ADDR_NEGO 0 +#define ASPEED_PECI_2ND_BIT_OF_ADDR_NEGO 1 +#define ASPEED_PECI_MESSAGE_NEGO 2 +#define ASPEED_PECI_INT_MASK GENMASK(4, 0) +#define ASPEED_PECI_INT_BUS_TIMEOUT BIT(4) +#define ASPEED_PECI_INT_BUS_CONTENTION BIT(3) +#define ASPEED_PECI_INT_WR_FCS_BAD BIT(2) +#define ASPEED_PECI_INT_WR_FCS_ABORT BIT(1) +#define ASPEED_PECI_INT_CMD_DONE BIT(0) + +/* Interrupt Status Register */ +#define ASPEED_PECI_INT_STS 0x1c +#define ASPEED_PECI_INT_TIMING_RESULT_MASK GENMASK(29, 16) + /* bits[4..0]: Same bit fields in the 'Interrupt Register' */ + +/* Rx/Tx Data Buffer Registers */ +#define ASPEED_PECI_WR_DATA0 0x20 +#define ASPEED_PECI_WR_DATA1 0x24 +#define ASPEED_PECI_WR_DATA2 0x28 +#define ASPEED_PECI_WR_DATA3 0x2c +#define ASPEED_PECI_RD_DATA0 0x30 +#define ASPEED_PECI_RD_DATA1 0x34 +#define ASPEED_PECI_RD_DATA2 0x38 +#define ASPEED_PECI_RD_DATA3 0x3c +#define ASPEED_PECI_WR_DATA4 0x40 +#define ASPEED_PECI_WR_DATA5 0x44 +#define ASPEED_PECI_WR_DATA6 0x48 +#define ASPEED_PECI_WR_DATA7 0x4c +#define ASPEED_PECI_RD_DATA4 0x50 +#define ASPEED_PECI_RD_DATA5 0x54 +#define ASPEED_PECI_RD_DATA6 0x58 +#define ASPEED_PECI_RD_DATA7 0x5c +#define ASPEED_PECI_DATA_BUF_SIZE_MAX 32 + +/* Timing Negotiation */ +#define ASPEED_PECI_RD_SAMPLING_POINT_DEFAULT 8 +#define ASPEED_PECI_RD_SAMPLING_POINT_MAX (BIT(4) - 1) +#define ASPEED_PECI_CLK_DIV_DEFAULT 0 +#define ASPEED_PECI_CLK_DIV_MAX (BIT(3) - 1) +#define ASPEED_PECI_MSG_TIMING_DEFAULT 1 +#define ASPEED_PECI_MSG_TIMING_MAX (BIT(8) - 1) +#define ASPEED_PECI_ADDR_TIMING_DEFAULT 1 +#define ASPEED_PECI_ADDR_TIMING_MAX (BIT(8) - 1) + +/* Timeout */ +#define ASPEED_PECI_IDLE_CHECK_TIMEOUT_US (50 * USEC_PER_MSEC) +#define ASPEED_PECI_IDLE_CHECK_INTERVAL_US (10 * USEC_PER_MSEC) +#define ASPEED_PECI_CMD_TIMEOUT_MS_DEFAULT (1000) +#define ASPEED_PECI_CMD_TIMEOUT_MS_MAX (1000) + +struct aspeed_peci { + struct peci_controller *controller; + struct device *dev; + void __iomem *base; + struct clk *clk; + struct reset_control *rst; + int irq; + spinlock_t lock; /* to sync completion status handling */ + struct completion xfer_complete; + u32 status; + u32 cmd_timeout_ms; + u32 msg_timing; + u32 addr_timing; + u32 rd_sampling_point; + u32 clk_div; +}; + +static void aspeed_peci_init_regs(struct aspeed_peci *priv) +{ + u32 val; + + val = FIELD_PREP(ASPEED_PECI_CTRL_CLK_DIV_MASK, ASPEED_PECI_CLK_DIV_DEFAULT); + val |= ASPEED_PECI_CTRL_PECI_CLK_EN; + writel(val, priv->base + ASPEED_PECI_CTRL); + /* + * Timing negotiation period setting. + * The unit of the programmed value is 4 times of PECI clock period. + */ + val = FIELD_PREP(ASPEED_PECI_T_NEGO_MSG_MASK, priv->msg_timing); + val |= FIELD_PREP(ASPEED_PECI_T_NEGO_ADDR_MASK, priv->addr_timing); + writel(val, priv->base + ASPEED_PECI_TIMING_NEGOTIATION); + + /* Clear interrupts */ + val = readl(priv->base + ASPEED_PECI_INT_STS) | ASPEED_PECI_INT_MASK; + writel(val, priv->base + ASPEED_PECI_INT_STS); + + /* Set timing negotiation mode and enable interrupts */ + val = FIELD_PREP(ASPEED_PECI_TIMING_NEGO_SEL_MASK, ASPEED_PECI_1ST_BIT_OF_ADDR_NEGO); + val |= ASPEED_PECI_INT_MASK; + writel(val, priv->base + ASPEED_PECI_INT_CTRL); + + val = FIELD_PREP(ASPEED_PECI_CTRL_SAMPLING_MASK, priv->rd_sampling_point); + val |= FIELD_PREP(ASPEED_PECI_CTRL_CLK_DIV_MASK, priv->clk_div); + val |= ASPEED_PECI_CTRL_PECI_EN; + val |= ASPEED_PECI_CTRL_PECI_CLK_EN; + writel(val, priv->base + ASPEED_PECI_CTRL); +} + +static inline int aspeed_peci_check_idle(struct aspeed_peci *priv) +{ + u32 cmd_sts = readl(priv->base + ASPEED_PECI_CMD); + + if (FIELD_GET(ASPEED_PECI_CMD_STS_MASK, cmd_sts) == ASPEED_PECI_CMD_STS_ADDR_T_NEGO) + aspeed_peci_init_regs(priv); + + return readl_poll_timeout(priv->base + ASPEED_PECI_CMD, + cmd_sts, + !(cmd_sts & ASPEED_PECI_CMD_IDLE_MASK), + ASPEED_PECI_IDLE_CHECK_INTERVAL_US, + ASPEED_PECI_IDLE_CHECK_TIMEOUT_US); +} + +static int aspeed_peci_xfer(struct peci_controller *controller, + u8 addr, struct peci_request *req) +{ + struct aspeed_peci *priv = dev_get_drvdata(controller->dev.parent); + unsigned long flags, timeout = msecs_to_jiffies(priv->cmd_timeout_ms); + u32 peci_head; + int ret; + + if (req->tx.len > ASPEED_PECI_DATA_BUF_SIZE_MAX || + req->rx.len > ASPEED_PECI_DATA_BUF_SIZE_MAX) + return -EINVAL; + + /* Check command sts and bus idle state */ + ret = aspeed_peci_check_idle(priv); + if (ret) + return ret; /* -ETIMEDOUT */ + + spin_lock_irqsave(&priv->lock, flags); + reinit_completion(&priv->xfer_complete); + + peci_head = FIELD_PREP(ASPEED_PECI_TARGET_ADDR_MASK, addr) | + FIELD_PREP(ASPEED_PECI_WR_LEN_MASK, req->tx.len) | + FIELD_PREP(ASPEED_PECI_RD_LEN_MASK, req->rx.len); + + writel(peci_head, priv->base + ASPEED_PECI_RW_LENGTH); + + memcpy_toio(priv->base + ASPEED_PECI_WR_DATA0, req->tx.buf, min_t(u8, req->tx.len, 16)); + if (req->tx.len > 16) + memcpy_toio(priv->base + ASPEED_PECI_WR_DATA4, req->tx.buf + 16, + req->tx.len - 16); + + dev_dbg(priv->dev, "HEAD : 0x%08x\n", peci_head); + print_hex_dump_bytes("TX : ", DUMP_PREFIX_NONE, req->tx.buf, req->tx.len); + + priv->status = 0; + writel(ASPEED_PECI_CMD_FIRE, priv->base + ASPEED_PECI_CMD); + spin_unlock_irqrestore(&priv->lock, flags); + + ret = wait_for_completion_interruptible_timeout(&priv->xfer_complete, timeout); + if (ret < 0) + return ret; + + if (ret == 0) { + dev_dbg(priv->dev, "Timeout waiting for a response!\n"); + return -ETIMEDOUT; + } + + spin_lock_irqsave(&priv->lock, flags); + + writel(0, priv->base + ASPEED_PECI_CMD); + + if (priv->status != ASPEED_PECI_INT_CMD_DONE) { + spin_unlock_irqrestore(&priv->lock, flags); + dev_dbg(priv->dev, "No valid response!\n"); + return -EIO; + } + + spin_unlock_irqrestore(&priv->lock, flags); + + memcpy_fromio(req->rx.buf, priv->base + ASPEED_PECI_RD_DATA0, min_t(u8, req->rx.len, 16)); + if (req->rx.len > 16) + memcpy_fromio(req->rx.buf + 16, priv->base + ASPEED_PECI_RD_DATA4, + req->rx.len - 16); + + print_hex_dump_bytes("RX : ", DUMP_PREFIX_NONE, req->rx.buf, req->rx.len); + + return 0; +} + +static irqreturn_t aspeed_peci_irq_handler(int irq, void *arg) +{ + struct aspeed_peci *priv = arg; + u32 status; + + spin_lock(&priv->lock); + status = readl(priv->base + ASPEED_PECI_INT_STS); + writel(status, priv->base + ASPEED_PECI_INT_STS); + priv->status |= (status & ASPEED_PECI_INT_MASK); + + /* + * In most cases, interrupt bits will be set one by one but also note + * that multiple interrupt bits could be set at the same time. + */ + if (status & ASPEED_PECI_INT_BUS_TIMEOUT) + dev_dbg_ratelimited(priv->dev, "ASPEED_PECI_INT_BUS_TIMEOUT\n"); + + if (status & ASPEED_PECI_INT_BUS_CONTENTION) + dev_dbg_ratelimited(priv->dev, "ASPEED_PECI_INT_BUS_CONTENTION\n"); + + if (status & ASPEED_PECI_INT_WR_FCS_BAD) + dev_dbg_ratelimited(priv->dev, "ASPEED_PECI_INT_WR_FCS_BAD\n"); + + if (status & ASPEED_PECI_INT_WR_FCS_ABORT) + dev_dbg_ratelimited(priv->dev, "ASPEED_PECI_INT_WR_FCS_ABORT\n"); + + /* + * All commands should be ended up with a ASPEED_PECI_INT_CMD_DONE bit + * set even in an error case. + */ + if (status & ASPEED_PECI_INT_CMD_DONE) + complete(&priv->xfer_complete); + + spin_unlock(&priv->lock); + + return IRQ_HANDLED; +} + +static void aspeed_peci_property_sanitize(struct device *dev, const char *propname, + u32 min, u32 max, u32 default_val, u32 *propval) +{ + u32 val; + int ret; + + ret = device_property_read_u32(dev, propname, &val); + if (ret) { + val = default_val; + } else if (val > max || val < min) { + dev_warn(dev, "Invalid %s: %u, falling back to: %u\n", + propname, val, default_val); + + val = default_val; + } + + *propval = val; +} + +static void aspeed_peci_property_setup(struct aspeed_peci *priv) +{ + aspeed_peci_property_sanitize(priv->dev, "aspeed,clock-divider", + 0, ASPEED_PECI_CLK_DIV_MAX, + ASPEED_PECI_CLK_DIV_DEFAULT, &priv->clk_div); + aspeed_peci_property_sanitize(priv->dev, "aspeed,msg-timing", + 0, ASPEED_PECI_MSG_TIMING_MAX, + ASPEED_PECI_MSG_TIMING_DEFAULT, &priv->msg_timing); + aspeed_peci_property_sanitize(priv->dev, "aspeed,addr-timing", + 0, ASPEED_PECI_ADDR_TIMING_MAX, + ASPEED_PECI_ADDR_TIMING_DEFAULT, &priv->addr_timing); + aspeed_peci_property_sanitize(priv->dev, "aspeed,rd-sampling-point", + 0, ASPEED_PECI_RD_SAMPLING_POINT_MAX, + ASPEED_PECI_RD_SAMPLING_POINT_DEFAULT, + &priv->rd_sampling_point); + aspeed_peci_property_sanitize(priv->dev, "cmd-timeout-ms", + 1, ASPEED_PECI_CMD_TIMEOUT_MS_MAX, + ASPEED_PECI_CMD_TIMEOUT_MS_DEFAULT, &priv->cmd_timeout_ms); +} + +static struct peci_controller_ops aspeed_ops = { + .xfer = aspeed_peci_xfer, +}; + +static void aspeed_peci_reset_control_release(void *data) +{ + reset_control_assert(data); +} + +int aspeed_peci_reset_control_deassert(struct device *dev, struct reset_control *rst) +{ + int ret; + + ret = reset_control_deassert(rst); + if (ret) + return ret; + + return devm_add_action_or_reset(dev, aspeed_peci_reset_control_release, rst); +} + +static void aspeed_peci_clk_release(void *data) +{ + clk_disable_unprepare(data); +} + +static int aspeed_peci_clk_enable(struct device *dev, struct clk *clk) +{ + int ret; + + ret = clk_prepare_enable(clk); + if (ret) + return ret; + + return devm_add_action_or_reset(dev, aspeed_peci_clk_release, clk); +} + +static int aspeed_peci_probe(struct platform_device *pdev) +{ + struct peci_controller *controller; + struct aspeed_peci *priv; + int ret; + + priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->dev = &pdev->dev; + dev_set_drvdata(priv->dev, priv); + + priv->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(priv->base)) + return PTR_ERR(priv->base); + + priv->irq = platform_get_irq(pdev, 0); + if (!priv->irq) + return priv->irq; + + ret = devm_request_irq(&pdev->dev, priv->irq, aspeed_peci_irq_handler, + 0, "peci-aspeed", priv); + if (ret) + return ret; + + init_completion(&priv->xfer_complete); + spin_lock_init(&priv->lock); + + priv->rst = devm_reset_control_get(&pdev->dev, NULL); + if (IS_ERR(priv->rst)) + return dev_err_probe(priv->dev, PTR_ERR(priv->rst), + "failed to get reset control\n"); + + ret = aspeed_peci_reset_control_deassert(priv->dev, priv->rst); + if (ret) + return dev_err_probe(priv->dev, ret, "cannot deassert reset control\n"); + + priv->clk = devm_clk_get(priv->dev, NULL); + if (IS_ERR(priv->clk)) + return dev_err_probe(priv->dev, PTR_ERR(priv->clk), "failed to get clk\n"); + + ret = aspeed_peci_clk_enable(priv->dev, priv->clk); + if (ret) + return dev_err_probe(priv->dev, ret, "failed to enable clock\n"); + + aspeed_peci_property_setup(priv); + + aspeed_peci_init_regs(priv); + + controller = devm_peci_controller_add(priv->dev, &aspeed_ops); + if (IS_ERR(controller)) + return dev_err_probe(priv->dev, PTR_ERR(controller), + "failed to add aspeed peci controller\n"); + + priv->controller = controller; + + return 0; +} + +static const struct of_device_id aspeed_peci_of_table[] = { + { .compatible = "aspeed,ast2400-peci", }, + { .compatible = "aspeed,ast2500-peci", }, + { .compatible = "aspeed,ast2600-peci", }, + { } +}; +MODULE_DEVICE_TABLE(of, aspeed_peci_of_table); + +static struct platform_driver aspeed_peci_driver = { + .probe = aspeed_peci_probe, + .driver = { + .name = "peci-aspeed", + .of_match_table = aspeed_peci_of_table, + }, +}; +module_platform_driver(aspeed_peci_driver); + +MODULE_AUTHOR("Ryan Chen <ryan_chen@aspeedtech.com>"); +MODULE_AUTHOR("Jae Hyun Yoo <jae.hyun.yoo@linux.intel.com>"); +MODULE_DESCRIPTION("ASPEED PECI driver"); +MODULE_LICENSE("GPL"); +MODULE_IMPORT_NS(PECI);