This commit adds PECI adapter driver implementation for Aspeed AST24xx/AST25xx SoCs. Cc: Joel Stanley <joel@xxxxxxxxx> Cc: Andrew Jeffery <andrew@xxxxxxxx> Cc: Andy Shevchenko <andriy.shevchenko@xxxxxxxxx> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Cc: Robin Murphy <robin.murphy@xxxxxxx> Cc: Ryan Chen <ryan_chen@xxxxxxxxxxxxxx> Signed-off-by: Jae Hyun Yoo <jae.hyun.yoo@xxxxxxxxxxxxxxx> Reviewed-by: Haiyue Wang <haiyue.wang@xxxxxxxxxxxxxxx> Reviewed-by: James Feist <james.feist@xxxxxxxxxxxxxxx> Reviewed-by: Vernon Mauery <vernon.mauery@xxxxxxxxxxxxxxx> --- drivers/peci/Kconfig | 27 ++ drivers/peci/Makefile | 3 + drivers/peci/peci-aspeed.c | 505 +++++++++++++++++++++++++++++++++++++ 3 files changed, 535 insertions(+) create mode 100644 drivers/peci/peci-aspeed.c diff --git a/drivers/peci/Kconfig b/drivers/peci/Kconfig index 4ccacb22a356..9e9845ebcff4 100644 --- a/drivers/peci/Kconfig +++ b/drivers/peci/Kconfig @@ -10,3 +10,30 @@ config PECI The Platform Environment Control Interface (PECI) is a one-wire bus interface that provides a communication channel from Intel processors and chipset components to external monitoring or control devices. + + If you want PECI support, you should say Y here and also to the + specific driver for your bus adapter(s) below. + +if PECI + +# +# PECI hardware bus configuration +# + +menu "PECI Hardware Bus support" + +config PECI_ASPEED + tristate "ASPEED PECI support" + select REGMAP_MMIO + depends on OF + depends on ARCH_ASPEED || COMPILE_TEST + help + Say Y here if you want support for the Platform Environment Control + Interface (PECI) bus adapter driver on the ASPEED SoCs. + + This support is also available as a module. If so, the module + will be called peci-aspeed. + +endmenu + +endif # PECI diff --git a/drivers/peci/Makefile b/drivers/peci/Makefile index 9e8615e0d3ff..886285e69765 100644 --- a/drivers/peci/Makefile +++ b/drivers/peci/Makefile @@ -4,3 +4,6 @@ # Core functionality obj-$(CONFIG_PECI) += peci-core.o + +# Hardware specific bus drivers +obj-$(CONFIG_PECI_ASPEED) += peci-aspeed.o diff --git a/drivers/peci/peci-aspeed.c b/drivers/peci/peci-aspeed.c new file mode 100644 index 000000000000..2293d4e56e63 --- /dev/null +++ b/drivers/peci/peci-aspeed.c @@ -0,0 +1,505 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (C) 2012-2017 ASPEED Technology Inc. +// Copyright (c) 2018-2019 Intel Corporation + +#include <linux/bitfield.h> +#include <linux/clk.h> +#include <linux/interrupt.h> +#include <linux/jiffies.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/peci.h> +#include <linux/platform_device.h> +#include <linux/regmap.h> +#include <linux/reset.h> + +/* ASPEED PECI Registers */ +#define ASPEED_PECI_CTRL 0x00 +#define ASPEED_PECI_TIMING 0x04 +#define ASPEED_PECI_CMD 0x08 +#define ASPEED_PECI_CMD_CTRL 0x0c +#define ASPEED_PECI_EXP_FCS 0x10 +#define ASPEED_PECI_CAP_FCS 0x14 +#define ASPEED_PECI_INT_CTRL 0x18 +#define ASPEED_PECI_INT_STS 0x1c +#define ASPEED_PECI_W_DATA0 0x20 +#define ASPEED_PECI_W_DATA1 0x24 +#define ASPEED_PECI_W_DATA2 0x28 +#define ASPEED_PECI_W_DATA3 0x2c +#define ASPEED_PECI_R_DATA0 0x30 +#define ASPEED_PECI_R_DATA1 0x34 +#define ASPEED_PECI_R_DATA2 0x38 +#define ASPEED_PECI_R_DATA3 0x3c +#define ASPEED_PECI_W_DATA4 0x40 +#define ASPEED_PECI_W_DATA5 0x44 +#define ASPEED_PECI_W_DATA6 0x48 +#define ASPEED_PECI_W_DATA7 0x4c +#define ASPEED_PECI_R_DATA4 0x50 +#define ASPEED_PECI_R_DATA5 0x54 +#define ASPEED_PECI_R_DATA6 0x58 +#define ASPEED_PECI_R_DATA7 0x5c + +/* ASPEED_PECI_CTRL - 0x00 : Control Register */ +#define PECI_CTRL_SAMPLING_MASK GENMASK(19, 16) +#define PECI_CTRL_READ_MODE_MASK GENMASK(13, 12) +#define PECI_CTRL_READ_MODE_COUNT BIT(12) +#define PECI_CTRL_READ_MODE_DBG BIT(13) +#define PECI_CTRL_CLK_SOURCE_MASK BIT(11) +#define PECI_CTRL_CLK_DIV_MASK GENMASK(10, 8) +#define PECI_CTRL_INVERT_OUT BIT(7) +#define PECI_CTRL_INVERT_IN BIT(6) +#define PECI_CTRL_BUS_CONTENT_EN BIT(5) +#define PECI_CTRL_PECI_EN BIT(4) +#define PECI_CTRL_PECI_CLK_EN BIT(0) + +/* ASPEED_PECI_TIMING - 0x04 : Timing Negotiation Register */ +#define PECI_TIMING_MESSAGE_MASK GENMASK(15, 8) +#define PECI_TIMING_ADDRESS_MASK GENMASK(7, 0) + +/* ASPEED_PECI_CMD - 0x08 : Command Register */ +#define PECI_CMD_PIN_MON BIT(31) +#define PECI_CMD_STS_MASK GENMASK(27, 24) +#define PECI_CMD_IDLE_MASK (PECI_CMD_STS_MASK | PECI_CMD_PIN_MON) +#define PECI_CMD_FIRE BIT(0) + +/* ASPEED_PECI_LEN - 0x0C : Read/Write Length Register */ +#define PECI_AW_FCS_EN BIT(31) +#define PECI_READ_LEN_MASK GENMASK(23, 16) +#define PECI_WRITE_LEN_MASK GENMASK(15, 8) +#define PECI_TAGET_ADDR_MASK GENMASK(7, 0) + +/* ASPEED_PECI_EXP_FCS - 0x10 : Expected FCS Data Register */ +#define PECI_EXPECT_READ_FCS_MASK GENMASK(23, 16) +#define PECI_EXPECT_AW_FCS_AUTO_MASK GENMASK(15, 8) +#define PECI_EXPECT_WRITE_FCS_MASK GENMASK(7, 0) + +/* ASPEED_PECI_CAP_FCS - 0x14 : Captured FCS Data Register */ +#define PECI_CAPTURE_READ_FCS_MASK GENMASK(23, 16) +#define PECI_CAPTURE_WRITE_FCS_MASK GENMASK(7, 0) + +/* ASPEED_PECI_INT_CTRL/STS - 0x18/0x1c : Interrupt Register */ +#define PECI_INT_TIMING_RESULT_MASK GENMASK(31, 30) +#define PECI_INT_TIMEOUT BIT(4) +#define PECI_INT_CONNECT BIT(3) +#define PECI_INT_W_FCS_BAD BIT(2) +#define PECI_INT_W_FCS_ABORT BIT(1) +#define PECI_INT_CMD_DONE BIT(0) + +#define PECI_INT_MASK (PECI_INT_TIMEOUT | PECI_INT_CONNECT | \ + PECI_INT_W_FCS_BAD | PECI_INT_W_FCS_ABORT | \ + PECI_INT_CMD_DONE) + +#define PECI_IDLE_CHECK_TIMEOUT_USEC 50000 +#define PECI_IDLE_CHECK_INTERVAL_USEC 10000 + +#define PECI_RD_SAMPLING_POINT_DEFAULT 8 +#define PECI_RD_SAMPLING_POINT_MAX 15 +#define PECI_CLK_DIV_DEFAULT 0 +#define PECI_CLK_DIV_MAX 7 +#define PECI_MSG_TIMING_DEFAULT 1 +#define PECI_MSG_TIMING_MAX 255 +#define PECI_ADDR_TIMING_DEFAULT 1 +#define PECI_ADDR_TIMING_MAX 255 +#define PECI_CMD_TIMEOUT_MS_DEFAULT 1000 +#define PECI_CMD_TIMEOUT_MS_MAX 60000 + +struct aspeed_peci { + struct peci_adapter *adapter; + struct device *dev; + struct regmap *regmap; + 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; +}; + +static int aspeed_peci_xfer_native(struct aspeed_peci *priv, + struct peci_xfer_msg *msg) +{ + long err, timeout = msecs_to_jiffies(priv->cmd_timeout_ms); + u32 peci_head, peci_state, rx_data, cmd_sts; + unsigned long flags; + int i, rc; + uint reg; + + /* Check command sts and bus idle state */ + rc = regmap_read_poll_timeout(priv->regmap, ASPEED_PECI_CMD, cmd_sts, + !(cmd_sts & PECI_CMD_IDLE_MASK), + PECI_IDLE_CHECK_INTERVAL_USEC, + PECI_IDLE_CHECK_TIMEOUT_USEC); + if (rc) + return rc; /* -ETIMEDOUT */ + + spin_lock_irqsave(&priv->lock, flags); + reinit_completion(&priv->xfer_complete); + + peci_head = FIELD_PREP(PECI_TAGET_ADDR_MASK, msg->addr) | + FIELD_PREP(PECI_WRITE_LEN_MASK, msg->tx_len) | + FIELD_PREP(PECI_READ_LEN_MASK, msg->rx_len); + + regmap_write(priv->regmap, ASPEED_PECI_CMD_CTRL, peci_head); + + for (i = 0; i < msg->tx_len; i += 4) { + reg = i < 16 ? ASPEED_PECI_W_DATA0 + i % 16 : + ASPEED_PECI_W_DATA4 + i % 16; + regmap_write(priv->regmap, reg, + le32_to_cpup((__le32 *)&msg->tx_buf[i])); + } + + dev_dbg(priv->dev, "HEAD : 0x%08x\n", peci_head); + print_hex_dump_debug("TX : ", DUMP_PREFIX_NONE, 16, 1, + msg->tx_buf, msg->tx_len, true); + + priv->status = 0; + regmap_write(priv->regmap, ASPEED_PECI_CMD, PECI_CMD_FIRE); + spin_unlock_irqrestore(&priv->lock, flags); + + err = wait_for_completion_interruptible_timeout(&priv->xfer_complete, + timeout); + + spin_lock_irqsave(&priv->lock, flags); + dev_dbg(priv->dev, "INT_STS : 0x%08x\n", priv->status); + regmap_read(priv->regmap, ASPEED_PECI_CMD, &peci_state); + dev_dbg(priv->dev, "PECI_STATE : 0x%lx\n", + FIELD_GET(PECI_CMD_STS_MASK, peci_state)); + + regmap_write(priv->regmap, ASPEED_PECI_CMD, 0); + + if (err <= 0 || priv->status != PECI_INT_CMD_DONE) { + if (err < 0) { /* -ERESTARTSYS */ + rc = (int)err; + goto err_irqrestore; + } else if (err == 0) { + dev_dbg(priv->dev, "Timeout waiting for a response!\n"); + rc = -ETIMEDOUT; + goto err_irqrestore; + } + + dev_dbg(priv->dev, "No valid response!\n"); + rc = -EIO; + goto err_irqrestore; + } + + /** + * Note that rx_len and rx_buf size can be an odd number. + * Byte handling is more efficient. + */ + for (i = 0; i < msg->rx_len; i++) { + u8 byte_offset = i % 4; + + if (byte_offset == 0) { + reg = i < 16 ? ASPEED_PECI_R_DATA0 + i % 16 : + ASPEED_PECI_R_DATA4 + i % 16; + regmap_read(priv->regmap, reg, &rx_data); + } + + msg->rx_buf[i] = (u8)(rx_data >> (byte_offset << 3)); + } + + print_hex_dump_debug("RX : ", DUMP_PREFIX_NONE, 16, 1, + msg->rx_buf, msg->rx_len, true); + + regmap_read(priv->regmap, ASPEED_PECI_CMD, &peci_state); + dev_dbg(priv->dev, "PECI_STATE : 0x%lx\n", + FIELD_GET(PECI_CMD_STS_MASK, peci_state)); + dev_dbg(priv->dev, "------------------------\n"); + +err_irqrestore: + spin_unlock_irqrestore(&priv->lock, flags); + return rc; +} + +static irqreturn_t aspeed_peci_irq_handler(int irq, void *arg) +{ + struct aspeed_peci *priv = arg; + u32 status_ack = 0; + u32 status; + + spin_lock(&priv->lock); + regmap_read(priv->regmap, ASPEED_PECI_INT_STS, &status); + priv->status |= (status & 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 & PECI_INT_TIMEOUT) { + dev_dbg(priv->dev, "PECI_INT_TIMEOUT\n"); + status_ack |= PECI_INT_TIMEOUT; + } + + if (status & PECI_INT_CONNECT) { + dev_dbg(priv->dev, "PECI_INT_CONNECT\n"); + status_ack |= PECI_INT_CONNECT; + } + + if (status & PECI_INT_W_FCS_BAD) { + dev_dbg(priv->dev, "PECI_INT_W_FCS_BAD\n"); + status_ack |= PECI_INT_W_FCS_BAD; + } + + if (status & PECI_INT_W_FCS_ABORT) { + dev_dbg(priv->dev, "PECI_INT_W_FCS_ABORT\n"); + status_ack |= PECI_INT_W_FCS_ABORT; + } + + /** + * All commands should be ended up with a PECI_INT_CMD_DONE bit set + * even in an error case. + */ + if (status & PECI_INT_CMD_DONE) { + dev_dbg(priv->dev, "PECI_INT_CMD_DONE\n"); + status_ack |= PECI_INT_CMD_DONE; + complete(&priv->xfer_complete); + } + + regmap_write(priv->regmap, ASPEED_PECI_INT_STS, status_ack); + spin_unlock(&priv->lock); + return IRQ_HANDLED; +} + +static int aspeed_peci_init_ctrl(struct aspeed_peci *priv) +{ + u32 msg_timing, addr_timing, rd_sampling_point; + u32 clk_freq, clk_divisor, clk_div_val = 0; + int ret; + + priv->clk = devm_clk_get(priv->dev, NULL); + if (IS_ERR(priv->clk)) { + dev_err(priv->dev, "Failed to get clk source.\n"); + return PTR_ERR(priv->clk); + } + + ret = clk_prepare_enable(priv->clk); + if (ret) { + dev_err(priv->dev, "Failed to enable clock.\n"); + return ret; + } + + ret = of_property_read_u32(priv->dev->of_node, "clock-frequency", + &clk_freq); + if (ret) { + dev_err(priv->dev, + "Could not read clock-frequency property.\n"); + clk_disable_unprepare(priv->clk); + return ret; + } + + clk_divisor = clk_get_rate(priv->clk) / clk_freq; + + while ((clk_divisor >> 1) && (clk_div_val < PECI_CLK_DIV_MAX)) + clk_div_val++; + + ret = of_property_read_u32(priv->dev->of_node, "msg-timing", + &msg_timing); + if (ret || msg_timing > PECI_MSG_TIMING_MAX) { + if (!ret) + dev_warn(priv->dev, + "Invalid msg-timing : %u, Use default : %u\n", + msg_timing, PECI_MSG_TIMING_DEFAULT); + msg_timing = PECI_MSG_TIMING_DEFAULT; + } + + ret = of_property_read_u32(priv->dev->of_node, "addr-timing", + &addr_timing); + if (ret || addr_timing > PECI_ADDR_TIMING_MAX) { + if (!ret) + dev_warn(priv->dev, + "Invalid addr-timing : %u, Use default : %u\n", + addr_timing, PECI_ADDR_TIMING_DEFAULT); + addr_timing = PECI_ADDR_TIMING_DEFAULT; + } + + ret = of_property_read_u32(priv->dev->of_node, "rd-sampling-point", + &rd_sampling_point); + if (ret || rd_sampling_point > PECI_RD_SAMPLING_POINT_MAX) { + if (!ret) + dev_warn(priv->dev, + "Invalid rd-sampling-point : %u. Use default : %u\n", + rd_sampling_point, + PECI_RD_SAMPLING_POINT_DEFAULT); + rd_sampling_point = PECI_RD_SAMPLING_POINT_DEFAULT; + } + + ret = of_property_read_u32(priv->dev->of_node, "cmd-timeout-ms", + &priv->cmd_timeout_ms); + if (ret || priv->cmd_timeout_ms > PECI_CMD_TIMEOUT_MS_MAX || + priv->cmd_timeout_ms == 0) { + if (!ret) + dev_warn(priv->dev, + "Invalid cmd-timeout-ms : %u. Use default : %u\n", + priv->cmd_timeout_ms, + PECI_CMD_TIMEOUT_MS_DEFAULT); + priv->cmd_timeout_ms = PECI_CMD_TIMEOUT_MS_DEFAULT; + } + + regmap_write(priv->regmap, ASPEED_PECI_CTRL, + FIELD_PREP(PECI_CTRL_CLK_DIV_MASK, PECI_CLK_DIV_DEFAULT) | + PECI_CTRL_PECI_CLK_EN); + + /** + * Timing negotiation period setting. + * The unit of the programmed value is 4 times of PECI clock period. + */ + regmap_write(priv->regmap, ASPEED_PECI_TIMING, + FIELD_PREP(PECI_TIMING_MESSAGE_MASK, msg_timing) | + FIELD_PREP(PECI_TIMING_ADDRESS_MASK, addr_timing)); + + /* Clear interrupts */ + regmap_write(priv->regmap, ASPEED_PECI_INT_STS, PECI_INT_MASK); + + /* Enable interrupts */ + regmap_write(priv->regmap, ASPEED_PECI_INT_CTRL, PECI_INT_MASK); + + /* Read sampling point and clock speed setting */ + regmap_write(priv->regmap, ASPEED_PECI_CTRL, + FIELD_PREP(PECI_CTRL_SAMPLING_MASK, rd_sampling_point) | + FIELD_PREP(PECI_CTRL_CLK_DIV_MASK, clk_div_val) | + PECI_CTRL_PECI_EN | PECI_CTRL_PECI_CLK_EN); + + return 0; +} + +static const struct regmap_config aspeed_peci_regmap_config = { + .reg_bits = 32, + .val_bits = 32, + .reg_stride = 4, + .max_register = ASPEED_PECI_R_DATA7, + .val_format_endian = REGMAP_ENDIAN_LITTLE, + .fast_io = true, +}; + +static int aspeed_peci_xfer(struct peci_adapter *adapter, + struct peci_xfer_msg *msg) +{ + struct aspeed_peci *priv = peci_get_adapdata(adapter); + + return aspeed_peci_xfer_native(priv, msg); +} + +static int aspeed_peci_probe(struct platform_device *pdev) +{ + struct peci_adapter *adapter; + struct aspeed_peci *priv; + struct resource *res; + void __iomem *base; + u32 cmd_sts; + int ret; + + adapter = peci_alloc_adapter(&pdev->dev, sizeof(*priv)); + if (!adapter) + return -ENOMEM; + + priv = peci_get_adapdata(adapter); + priv->adapter = adapter; + priv->dev = &pdev->dev; + dev_set_drvdata(&pdev->dev, priv); + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(base)) { + ret = PTR_ERR(base); + goto err_put_adapter_dev; + } + + priv->regmap = devm_regmap_init_mmio(&pdev->dev, base, + &aspeed_peci_regmap_config); + if (IS_ERR(priv->regmap)) { + ret = PTR_ERR(priv->regmap); + goto err_put_adapter_dev; + } + + /** + * We check that the regmap works on this very first access, + * but as this is an MMIO-backed regmap, subsequent regmap + * access is not going to fail and we skip error checks from + * this point. + */ + ret = regmap_read(priv->regmap, ASPEED_PECI_CMD, &cmd_sts); + if (ret) { + ret = -EIO; + goto err_put_adapter_dev; + } + + priv->irq = platform_get_irq(pdev, 0); + if (!priv->irq) { + ret = -ENODEV; + goto err_put_adapter_dev; + } + + ret = devm_request_irq(&pdev->dev, priv->irq, aspeed_peci_irq_handler, + 0, "peci-aspeed-irq", priv); + if (ret) + goto err_put_adapter_dev; + + init_completion(&priv->xfer_complete); + spin_lock_init(&priv->lock); + + priv->adapter->owner = THIS_MODULE; + priv->adapter->dev.of_node = of_node_get(dev_of_node(priv->dev)); + strlcpy(priv->adapter->name, pdev->name, sizeof(priv->adapter->name)); + priv->adapter->xfer = aspeed_peci_xfer; + + priv->rst = devm_reset_control_get(&pdev->dev, NULL); + if (IS_ERR(priv->rst)) { + dev_err(&pdev->dev, + "missing or invalid reset controller entry"); + ret = PTR_ERR(priv->rst); + goto err_put_adapter_dev; + } + reset_control_deassert(priv->rst); + + ret = aspeed_peci_init_ctrl(priv); + if (ret) + goto err_put_adapter_dev; + + ret = peci_add_adapter(priv->adapter); + if (ret) + goto err_put_adapter_dev; + + dev_info(&pdev->dev, "peci bus %d registered, irq %d\n", + priv->adapter->nr, priv->irq); + + return 0; + +err_put_adapter_dev: + put_device(&adapter->dev); + return ret; +} + +static int aspeed_peci_remove(struct platform_device *pdev) +{ + struct aspeed_peci *priv = dev_get_drvdata(&pdev->dev); + + clk_disable_unprepare(priv->clk); + reset_control_assert(priv->rst); + peci_del_adapter(priv->adapter); + of_node_put(priv->adapter->dev.of_node); + + return 0; +} + +static const struct of_device_id aspeed_peci_of_table[] = { + { .compatible = "aspeed,ast2400-peci", }, + { .compatible = "aspeed,ast2500-peci", }, + { } +}; +MODULE_DEVICE_TABLE(of, aspeed_peci_of_table); + +static struct platform_driver aspeed_peci_driver = { + .probe = aspeed_peci_probe, + .remove = aspeed_peci_remove, + .driver = { + .name = "peci-aspeed", + .of_match_table = of_match_ptr(aspeed_peci_of_table), + }, +}; +module_platform_driver(aspeed_peci_driver); + +MODULE_AUTHOR("Ryan Chen <ryan_chen@xxxxxxxxxxxxxx>"); +MODULE_AUTHOR("Jae Hyun Yoo <jae.hyun.yoo@xxxxxxxxxxxxxxx>"); +MODULE_DESCRIPTION("ASPEED PECI driver"); +MODULE_LICENSE("GPL v2"); -- 2.20.1