Re: [PATCH v2 25/36] platform/x86: intel_pmc_ipc: Start using SCU IPC

From: Andy Shevchenko
Date: Wed Jan 08 2020 - 11:52:36 EST


On Wed, Jan 08, 2020 at 02:41:50PM +0300, Mika Westerberg wrote:
> SCU IPC is pretty much the same IPC implemented in the intel_pmc_ipc
> driver so drop the duplicate implementation and call directly the SCU
> IPC.
>

Reviewed-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>

Couple of nits below.

> Signed-off-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>
> ---
> drivers/platform/x86/Kconfig | 1 +
> drivers/platform/x86/intel_pmc_ipc.c | 299 +++++----------------------
> 2 files changed, 48 insertions(+), 252 deletions(-)
>
> diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig
> index e9ba81fc1770..797683c5d005 100644
> --- a/drivers/platform/x86/Kconfig
> +++ b/drivers/platform/x86/Kconfig
> @@ -1193,6 +1193,7 @@ config INTEL_SMARTCONNECT
> config INTEL_PMC_IPC
> tristate "Intel PMC IPC Driver"
> depends on ACPI && PCI
> + select INTEL_SCU_IPC
> ---help---
> This driver provides support for PMC control on some Intel platforms.
> The PMC is an ARC processor which defines IPC commands for communication
> diff --git a/drivers/platform/x86/intel_pmc_ipc.c b/drivers/platform/x86/intel_pmc_ipc.c
> index 8527327d88c7..10505fbd01b5 100644
> --- a/drivers/platform/x86/intel_pmc_ipc.c
> +++ b/drivers/platform/x86/intel_pmc_ipc.c
> @@ -21,28 +21,10 @@
> #include <linux/platform_device.h>
>
> #include <asm/intel_pmc_ipc.h>
> +#include <asm/intel_scu_ipc.h>
>
> #include <linux/platform_data/itco_wdt.h>
>
> -/*
> - * IPC registers
> - * The IA write to IPC_CMD command register triggers an interrupt to the ARC,
> - * The ARC handles the interrupt and services it, writing optional data to
> - * the IPC1 registers, updates the IPC_STS response register with the status.
> - */
> -#define IPC_CMD 0x00
> -#define IPC_CMD_MSI BIT(8)
> -#define IPC_CMD_SIZE 16
> -#define IPC_CMD_SUBCMD 12
> -#define IPC_STATUS 0x04
> -#define IPC_STATUS_IRQ BIT(2)
> -#define IPC_STATUS_ERR BIT(1)
> -#define IPC_STATUS_BUSY BIT(0)
> -#define IPC_SPTR 0x08
> -#define IPC_DPTR 0x0C
> -#define IPC_WRITE_BUFFER 0x80
> -#define IPC_READ_BUFFER 0x90
> -
> /* Residency with clock rate at 19.2MHz to usecs */
> #define S0IX_RESIDENCY_IN_USECS(d, s) \
> ({ \
> @@ -51,16 +33,6 @@
> result; \
> })
>
> -/*
> - * 16-byte buffer for sending data associated with IPC command.
> - */
> -#define IPC_DATA_BUFFER_SIZE 16
> -
> -#define IPC_LOOP_CNT 3000000
> -#define IPC_MAX_SEC 3
> -
> -#define IPC_TRIGGER_MODE_IRQ true
> -
> /* exported resources from IFWI */
> #define PLAT_RESOURCE_IPC_INDEX 0
> #define PLAT_RESOURCE_IPC_SIZE 0x1000
> @@ -103,11 +75,6 @@
>
> static struct intel_pmc_ipc_dev {
> struct device *dev;
> - void __iomem *ipc_base;
> - bool irq_mode;
> - int irq;
> - int cmd;
> - struct completion cmd_complete;
>
> /* The following PMC BARs share the same ACPI device with the IPC */
> resource_size_t acpi_io_base;
> @@ -132,53 +99,6 @@ static struct intel_pmc_ipc_dev {
> struct platform_device *telemetry_dev;
> } ipcdev;
>
> -static char *ipc_err_sources[] = {
> - [IPC_ERR_NONE] =
> - "no error",
> - [IPC_ERR_CMD_NOT_SUPPORTED] =
> - "command not supported",
> - [IPC_ERR_CMD_NOT_SERVICED] =
> - "command not serviced",
> - [IPC_ERR_UNABLE_TO_SERVICE] =
> - "unable to service",
> - [IPC_ERR_CMD_INVALID] =
> - "command invalid",
> - [IPC_ERR_CMD_FAILED] =
> - "command failed",
> - [IPC_ERR_EMSECURITY] =
> - "Invalid Battery",
> - [IPC_ERR_UNSIGNEDKERNEL] =
> - "Unsigned kernel",
> -};
> -
> -/* Prevent concurrent calls to the PMC */
> -static DEFINE_MUTEX(ipclock);
> -
> -static inline void ipc_send_command(u32 cmd)
> -{
> - ipcdev.cmd = cmd;
> - if (ipcdev.irq_mode) {
> - reinit_completion(&ipcdev.cmd_complete);
> - cmd |= IPC_CMD_MSI;
> - }
> - writel(cmd, ipcdev.ipc_base + IPC_CMD);
> -}
> -
> -static inline u32 ipc_read_status(void)
> -{
> - return readl(ipcdev.ipc_base + IPC_STATUS);
> -}
> -
> -static inline void ipc_data_writel(u32 data, u32 offset)
> -{
> - writel(data, ipcdev.ipc_base + IPC_WRITE_BUFFER + offset);
> -}
> -
> -static inline u32 ipc_data_readl(u32 offset)
> -{
> - return readl(ipcdev.ipc_base + IPC_READ_BUFFER + offset);
> -}
> -
> static inline u64 gcr_data_readq(u32 offset)
> {
> return readq(ipcdev.gcr_mem_base + offset);
> @@ -274,127 +194,6 @@ static int update_no_reboot_bit(void *priv, bool set)
> PMC_CFG_NO_REBOOT_MASK, value);
> }
>
> -static int intel_pmc_ipc_check_status(void)
> -{
> - int status;
> - int ret = 0;
> -
> - if (ipcdev.irq_mode) {
> - if (0 == wait_for_completion_timeout(
> - &ipcdev.cmd_complete, IPC_MAX_SEC * HZ))
> - ret = -ETIMEDOUT;
> - } else {
> - int loop_count = IPC_LOOP_CNT;
> -
> - while ((ipc_read_status() & IPC_STATUS_BUSY) && --loop_count)
> - udelay(1);
> - if (loop_count == 0)
> - ret = -ETIMEDOUT;
> - }
> -
> - status = ipc_read_status();
> - if (ret == -ETIMEDOUT) {
> - dev_err(ipcdev.dev,
> - "IPC timed out, TS=0x%x, CMD=0x%x\n",
> - status, ipcdev.cmd);
> - return ret;
> - }
> -
> - if (status & IPC_STATUS_ERR) {
> - int i;
> -
> - ret = -EIO;
> - i = (status >> IPC_CMD_SIZE) & 0xFF;
> - if (i < ARRAY_SIZE(ipc_err_sources))
> - dev_err(ipcdev.dev,
> - "IPC failed: %s, STS=0x%x, CMD=0x%x\n",
> - ipc_err_sources[i], status, ipcdev.cmd);
> - else
> - dev_err(ipcdev.dev,
> - "IPC failed: unknown, STS=0x%x, CMD=0x%x\n",
> - status, ipcdev.cmd);
> - if ((i == IPC_ERR_UNSIGNEDKERNEL) || (i == IPC_ERR_EMSECURITY))
> - ret = -EACCES;
> - }
> -
> - return ret;
> -}
> -
> -/**
> - * intel_pmc_ipc_simple_command() - Simple IPC command
> - * @cmd: IPC command code.
> - * @sub: IPC command sub type.
> - *
> - * Send a simple IPC command to PMC when don't need to specify
> - * input/output data and source/dest pointers.
> - *
> - * Return: an IPC error code or 0 on success.
> - */
> -static int intel_pmc_ipc_simple_command(int cmd, int sub)
> -{
> - int ret;
> -
> - mutex_lock(&ipclock);
> - if (ipcdev.dev == NULL) {
> - mutex_unlock(&ipclock);
> - return -ENODEV;
> - }
> - ipc_send_command(sub << IPC_CMD_SUBCMD | cmd);
> - ret = intel_pmc_ipc_check_status();
> - mutex_unlock(&ipclock);
> -
> - return ret;
> -}
> -
> -/**
> - * intel_pmc_ipc_raw_cmd() - IPC command with data and pointers
> - * @cmd: IPC command code.
> - * @sub: IPC command sub type.
> - * @in: input data of this IPC command.
> - * @inlen: input data length in bytes.
> - * @out: output data of this IPC command.
> - * @outlen: output data length in dwords.
> - * @sptr: data writing to SPTR register.
> - * @dptr: data writing to DPTR register.
> - *
> - * Send an IPC command to PMC with input/output data and source/dest pointers.
> - *
> - * Return: an IPC error code or 0 on success.
> - */
> -static int intel_pmc_ipc_raw_cmd(u32 cmd, u32 sub, u8 *in, u32 inlen, u32 *out,
> - u32 outlen, u32 dptr, u32 sptr)
> -{
> - u32 wbuf[4] = { 0 };
> - int ret;
> - int i;
> -
> - if (inlen > IPC_DATA_BUFFER_SIZE || outlen > IPC_DATA_BUFFER_SIZE / 4)
> - return -EINVAL;
> -
> - mutex_lock(&ipclock);
> - if (ipcdev.dev == NULL) {
> - mutex_unlock(&ipclock);
> - return -ENODEV;
> - }
> - memcpy(wbuf, in, inlen);
> - writel(dptr, ipcdev.ipc_base + IPC_DPTR);
> - writel(sptr, ipcdev.ipc_base + IPC_SPTR);
> - /* The input data register is 32bit register and inlen is in Byte */
> - for (i = 0; i < ((inlen + 3) / 4); i++)
> - ipc_data_writel(wbuf[i], 4 * i);
> - ipc_send_command((inlen << IPC_CMD_SIZE) |
> - (sub << IPC_CMD_SUBCMD) | cmd);
> - ret = intel_pmc_ipc_check_status();
> - if (!ret) {
> - /* out is read from 32bit register and outlen is in 32bit */
> - for (i = 0; i < outlen; i++)
> - *out++ = ipc_data_readl(4 * i);
> - }
> - mutex_unlock(&ipclock);
> -
> - return ret;
> -}
> -
> /**
> * intel_pmc_ipc_command() - IPC command with input/output data
> * @cmd: IPC command code.
> @@ -411,34 +210,23 @@ static int intel_pmc_ipc_raw_cmd(u32 cmd, u32 sub, u8 *in, u32 inlen, u32 *out,
> int intel_pmc_ipc_command(u32 cmd, u32 sub, u8 *in, u32 inlen,
> u32 *out, u32 outlen)
> {
> - return intel_pmc_ipc_raw_cmd(cmd, sub, in, inlen, out, outlen, 0, 0);

> + return intel_scu_ipc_dev_command(NULL, cmd, sub, in, inlen, out,
> + outlen);

I would leave it on one line.

> }
> EXPORT_SYMBOL_GPL(intel_pmc_ipc_command);
>
> -static irqreturn_t ioc(int irq, void *dev_id)
> -{
> - int status;
> -
> - if (ipcdev.irq_mode) {
> - status = ipc_read_status();
> - writel(status | IPC_STATUS_IRQ, ipcdev.ipc_base + IPC_STATUS);
> - }
> - complete(&ipcdev.cmd_complete);
> -
> - return IRQ_HANDLED;
> -}
> -
> static int ipc_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
> {
> struct intel_pmc_ipc_dev *pmc = &ipcdev;
> + struct intel_scu_ipc_pdata pdata;
> + struct intel_scu_ipc_dev *scu;
> int ret;
>
> /* Only one PMC is supported */
> if (pmc->dev)
> return -EBUSY;
>
> - pmc->irq_mode = IPC_TRIGGER_MODE_IRQ;
> -
> + memset(&pdata, 0, sizeof(pdata));
> spin_lock_init(&ipcdev.gcr_lock);
>
> ret = pcim_enable_device(pdev);
> @@ -449,24 +237,25 @@ static int ipc_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
> if (ret)
> return ret;
>
> - init_completion(&pmc->cmd_complete);
> -
> - pmc->ipc_base = pcim_iomap_table(pdev)[0];
> + pdata.ipc_regs = pcim_iomap_table(pdev)[0];
>
> - ret = devm_request_irq(&pdev->dev, pdev->irq, ioc, 0, "intel_pmc_ipc",
> - pmc);
> - if (ret) {
> - dev_err(&pdev->dev, "Failed to request irq\n");
> - return ret;
> - }
> + scu = intel_scu_ipc_probe(&pdev->dev, &pdata);
> + if (IS_ERR(scu))
> + return PTR_ERR(scu);
>
> pmc->dev = &pdev->dev;
>
> - pci_set_drvdata(pdev, pmc);
> + pci_set_drvdata(pdev, scu);
>
> return 0;
> }
>
> +static void ipc_pci_remove(struct pci_dev *pdev)
> +{
> + intel_scu_ipc_remove(pci_get_drvdata(pdev));
> + ipcdev.dev = NULL;
> +}
> +
> static const struct pci_device_id ipc_pci_ids[] = {
> {PCI_VDEVICE(INTEL, 0x0a94), 0},
> {PCI_VDEVICE(INTEL, 0x1a94), 0},
> @@ -479,12 +268,14 @@ static struct pci_driver ipc_pci_driver = {
> .name = "intel_pmc_ipc",
> .id_table = ipc_pci_ids,
> .probe = ipc_pci_probe,
> + .remove = ipc_pci_remove,
> };
>
> static ssize_t intel_pmc_ipc_simple_cmd_store(struct device *dev,
> struct device_attribute *attr,
> const char *buf, size_t count)
> {
> + struct intel_scu_ipc_dev *scu = dev_get_drvdata(dev);
> int subcmd;
> int cmd;
> int ret;
> @@ -495,7 +286,7 @@ static ssize_t intel_pmc_ipc_simple_cmd_store(struct device *dev,
> return -EINVAL;
> }
>
> - ret = intel_pmc_ipc_simple_command(cmd, subcmd);
> + ret = intel_scu_ipc_dev_simple_command(scu, cmd, subcmd);
> if (ret) {
> dev_err(dev, "command %d error with %d\n", cmd, ret);
> return ret;
> @@ -507,6 +298,7 @@ static ssize_t intel_pmc_ipc_northpeak_store(struct device *dev,
> struct device_attribute *attr,
> const char *buf, size_t count)
> {
> + struct intel_scu_ipc_dev *scu = dev_get_drvdata(dev);
> unsigned long val;
> int subcmd;
> int ret;
> @@ -518,7 +310,8 @@ static ssize_t intel_pmc_ipc_northpeak_store(struct device *dev,
> subcmd = 1;
> else
> subcmd = 0;
> - ret = intel_pmc_ipc_simple_command(PMC_IPC_NORTHPEAK_CTRL, subcmd);

> + ret = intel_scu_ipc_dev_simple_command(scu, PMC_IPC_NORTHPEAK_CTRL,
> + subcmd);

I would leave it on one line.

> if (ret) {
> dev_err(dev, "command north %d error with %d\n", subcmd, ret);
> return ret;
> @@ -711,7 +504,8 @@ static int ipc_create_pmc_devices(void)
> return ret;
> }
>
> -static int ipc_plat_get_res(struct platform_device *pdev)
> +static int ipc_plat_get_res(struct platform_device *pdev,
> + struct intel_scu_ipc_pdata *pdata)
> {
> struct resource *res, *punit_res = punit_res_array;
> void __iomem *addr;
> @@ -795,7 +589,7 @@ static int ipc_plat_get_res(struct platform_device *pdev)
> if (IS_ERR(addr))
> return PTR_ERR(addr);
>
> - ipcdev.ipc_base = addr;
> + pdata->ipc_regs = addr;
>
> ipcdev.gcr_mem_base = addr + PLAT_RESOURCE_GCR_OFFSET;
> dev_info(&pdev->dev, "ipc res: %pR\n", res);
> @@ -851,49 +645,50 @@ MODULE_DEVICE_TABLE(acpi, ipc_acpi_ids);
>
> static int ipc_plat_probe(struct platform_device *pdev)
> {
> + struct intel_scu_ipc_pdata pdata;
> + struct intel_scu_ipc_dev *scu;
> int ret;
>
> + memset(&pdata, 0, sizeof(pdata));
> + pdata.irq = platform_get_irq(pdev, 0);
> + if (pdata.irq < 0)
> + return -EINVAL;
> +
> ipcdev.dev = &pdev->dev;
> - ipcdev.irq_mode = IPC_TRIGGER_MODE_IRQ;
> - init_completion(&ipcdev.cmd_complete);
> spin_lock_init(&ipcdev.gcr_lock);
>
> - ipcdev.irq = platform_get_irq(pdev, 0);
> - if (ipcdev.irq < 0)
> - return -EINVAL;
> -
> - ret = ipc_plat_get_res(pdev);
> + ret = ipc_plat_get_res(pdev, &pdata);
> if (ret) {
> dev_err(&pdev->dev, "Failed to request resource\n");
> return ret;
> }
>
> + scu = intel_scu_ipc_probe(&pdev->dev, &pdata);
> + if (IS_ERR(scu))
> + return PTR_ERR(scu);
> +
> + platform_set_drvdata(pdev, scu);
> +
> ret = ipc_create_pmc_devices();
> if (ret) {
> dev_err(&pdev->dev, "Failed to create pmc devices\n");
> - return ret;
> - }
> -
> - if (devm_request_irq(&pdev->dev, ipcdev.irq, ioc, IRQF_NO_SUSPEND,
> - "intel_pmc_ipc", &ipcdev)) {
> - dev_err(&pdev->dev, "Failed to request irq\n");
> - ret = -EBUSY;
> - goto err_irq;
> + goto err_ipc;
> }
>
> ret = sysfs_create_group(&pdev->dev.kobj, &intel_ipc_group);
> if (ret) {
> dev_err(&pdev->dev, "Failed to create sysfs group %d\n",
> ret);
> - goto err_sys;
> + goto err_devs;
> }
>
> ipcdev.has_gcr_regs = true;
>
> return 0;
> -err_sys:
> - devm_free_irq(&pdev->dev, ipcdev.irq, &ipcdev);
> -err_irq:
> +
> +err_ipc:
> + intel_scu_ipc_remove(scu);
> +err_devs:
> platform_device_unregister(ipcdev.tco_dev);
> platform_device_unregister(ipcdev.punit_dev);
> platform_device_unregister(ipcdev.telemetry_dev);
> @@ -904,10 +699,10 @@ static int ipc_plat_probe(struct platform_device *pdev)
> static int ipc_plat_remove(struct platform_device *pdev)
> {
> sysfs_remove_group(&pdev->dev.kobj, &intel_ipc_group);
> - devm_free_irq(&pdev->dev, ipcdev.irq, &ipcdev);
> platform_device_unregister(ipcdev.tco_dev);
> platform_device_unregister(ipcdev.punit_dev);
> platform_device_unregister(ipcdev.telemetry_dev);
> + intel_scu_ipc_remove(platform_get_drvdata(pdev));
> ipcdev.dev = NULL;
> return 0;
> }
> --
> 2.24.1
>

--
With Best Regards,
Andy Shevchenko