Re: [PATCH v1 2/2] platform/x86: intel_pmc_ipc: Use regmap calls for GCR updates
From: Andy Shevchenko
Date: Fri Jan 26 2018 - 11:18:36 EST
On Fri, Jan 26, 2018 at 12:53 AM,
<sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx> wrote:
> From: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx>
>
> This patch adds support for regmap based implementation for GCR
> read/write/update APIs.
>
Thanks. On the first glance this one looks okay.
> Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx>
> ---
> drivers/platform/x86/Kconfig | 1 +
> drivers/platform/x86/intel_pmc_ipc.c | 124 +++++++++++++----------------------
> 2 files changed, 46 insertions(+), 79 deletions(-)
>
> This patch was originally part of "SCU/PMC/PUNIT IPC driver clean up" series. But I have
> split them into two sets because we need more thorough review on generic IPC driver
> design patches (second set).
>
> https://www.spinics.net/lists/linux-watchdog/msg12796.html
>
> Changes since previous set version (v8):
> * Removed gcr_mem_base variable.
>
> diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig
> index 2c745e8..ac618fd 100644
> --- a/drivers/platform/x86/Kconfig
> +++ b/drivers/platform/x86/Kconfig
> @@ -1087,6 +1087,7 @@ config PVPANIC
> config INTEL_PMC_IPC
> tristate "Intel PMC IPC Driver"
> depends on ACPI
> + select REGMAP_MMIO
> ---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 fadf721..650144a 100644
> --- a/drivers/platform/x86/intel_pmc_ipc.c
> +++ b/drivers/platform/x86/intel_pmc_ipc.c
> @@ -35,6 +35,7 @@
> #include <linux/acpi.h>
> #include <linux/io-64-nonatomic-lo-hi.h>
> #include <linux/spinlock.h>
> +#include <linux/regmap.h>
>
> #include <asm/intel_pmc_ipc.h>
>
> @@ -125,9 +126,7 @@ static struct intel_pmc_ipc_dev {
> struct completion cmd_complete;
>
> /* gcr */
> - void __iomem *gcr_mem_base;
> - bool has_gcr_regs;
> - spinlock_t gcr_lock;
> + struct regmap *gcr_regs;
> } ipcdev;
>
> static char *ipc_err_sources[] = {
> @@ -149,6 +148,15 @@ static char *ipc_err_sources[] = {
> "Unsigned kernel",
> };
>
> +static struct regmap_config gcr_regmap_config = {
> + .name = "intel_pmc_gcr",
> + .reg_bits = 32,
> + .reg_stride = 4,
> + .val_bits = 32,
> + .fast_io = true,
> + .max_register = PLAT_RESOURCE_GCR_SIZE,
> +};
> +
> /* Prevent concurrent calls to the PMC */
> static DEFINE_MUTEX(ipclock);
>
> @@ -182,21 +190,6 @@ 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);
> -}
> -
> -static inline int is_gcr_valid(u32 offset)
> -{
> - if (!ipcdev.has_gcr_regs)
> - return -EACCES;
> -
> - if (offset > PLAT_RESOURCE_GCR_SIZE)
> - return -EINVAL;
> -
> - return 0;
> -}
>
> /**
> * intel_pmc_gcr_read() - Read PMC GCR register
> @@ -209,21 +202,12 @@ static inline int is_gcr_valid(u32 offset)
> */
> int intel_pmc_gcr_read(u32 offset, u32 *data)
> {
> - int ret;
> -
> - spin_lock(&ipcdev.gcr_lock);
> -
> - ret = is_gcr_valid(offset);
> - if (ret < 0) {
> - spin_unlock(&ipcdev.gcr_lock);
> - return ret;
> - }
> -
> - *data = readl(ipcdev.gcr_mem_base + offset);
> + struct intel_pmc_ipc_dev *pmc = &ipcdev;
>
> - spin_unlock(&ipcdev.gcr_lock);
> + if (!pmc->gcr_regs)
> + return -EACCES;
>
> - return 0;
> + return regmap_read(pmc->gcr_regs, offset, data);
> }
> EXPORT_SYMBOL_GPL(intel_pmc_gcr_read);
>
> @@ -239,21 +223,12 @@ EXPORT_SYMBOL_GPL(intel_pmc_gcr_read);
> */
> int intel_pmc_gcr_write(u32 offset, u32 data)
> {
> - int ret;
> -
> - spin_lock(&ipcdev.gcr_lock);
> -
> - ret = is_gcr_valid(offset);
> - if (ret < 0) {
> - spin_unlock(&ipcdev.gcr_lock);
> - return ret;
> - }
> -
> - writel(data, ipcdev.gcr_mem_base + offset);
> + struct intel_pmc_ipc_dev *pmc = &ipcdev;
>
> - spin_unlock(&ipcdev.gcr_lock);
> + if (!pmc->gcr_regs)
> + return -EACCES;
>
> - return 0;
> + return regmap_write(pmc->gcr_regs, offset, data);
> }
> EXPORT_SYMBOL_GPL(intel_pmc_gcr_write);
>
> @@ -270,33 +245,12 @@ EXPORT_SYMBOL_GPL(intel_pmc_gcr_write);
> */
> int intel_pmc_gcr_update(u32 offset, u32 mask, u32 val)
> {
> - u32 new_val;
> - int ret = 0;
> -
> - spin_lock(&ipcdev.gcr_lock);
> -
> - ret = is_gcr_valid(offset);
> - if (ret < 0)
> - goto gcr_ipc_unlock;
> -
> - new_val = readl(ipcdev.gcr_mem_base + offset);
> -
> - new_val &= ~mask;
> - new_val |= val & mask;
> -
> - writel(new_val, ipcdev.gcr_mem_base + offset);
> -
> - new_val = readl(ipcdev.gcr_mem_base + offset);
> + struct intel_pmc_ipc_dev *pmc = &ipcdev;
>
> - /* check whether the bit update is successful */
> - if ((new_val & mask) != (val & mask)) {
> - ret = -EIO;
> - goto gcr_ipc_unlock;
> - }
> + if (!pmc->gcr_regs)
> + return -EACCES;
>
> -gcr_ipc_unlock:
> - spin_unlock(&ipcdev.gcr_lock);
> - return ret;
> + return regmap_update_bits(pmc->gcr_regs, offset, mask, val);
> }
> EXPORT_SYMBOL_GPL(intel_pmc_gcr_update);
>
> @@ -475,8 +429,6 @@ static int ipc_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
>
> pmc->irq_mode = IPC_TRIGGER_MODE_IRQ;
>
> - spin_lock_init(&ipcdev.gcr_lock);
> -
> ret = pcim_enable_device(pdev);
> if (ret)
> return ret;
> @@ -759,7 +711,6 @@ static int ipc_plat_get_res(struct platform_device *pdev)
> return PTR_ERR(addr);
>
> ipcdev.ipc_base = addr;
> - ipcdev.gcr_mem_base = addr + PLAT_RESOURCE_GCR_OFFSET;
>
> return 0;
> }
> @@ -772,17 +723,26 @@ static int ipc_plat_get_res(struct platform_device *pdev)
> */
> int intel_pmc_s0ix_counter_read(u64 *data)
> {
> + struct intel_pmc_ipc_dev *pmc = &ipcdev;
> u64 deep, shlw;
> + int ret;
>
> - if (!ipcdev.has_gcr_regs)
> + if (!pmc->gcr_regs)
> return -EACCES;
>
> - deep = gcr_data_readq(PMC_GCR_TELEM_DEEP_S0IX_REG);
> - shlw = gcr_data_readq(PMC_GCR_TELEM_SHLW_S0IX_REG);
> + ret = regmap_bulk_read(pmc->gcr_regs, PMC_GCR_TELEM_DEEP_S0IX_REG,
> + &deep, 2);
> + if (ret)
> + return ret;
> +
> + ret = regmap_bulk_read(pmc->gcr_regs, PMC_GCR_TELEM_SHLW_S0IX_REG,
> + &shlw, 2);
> + if (ret)
> + return ret;
>
> *data = S0IX_RESIDENCY_IN_USECS(deep, shlw);
>
> - return 0;
> + return ret;
> }
> EXPORT_SYMBOL_GPL(intel_pmc_s0ix_counter_read);
>
> @@ -801,7 +761,6 @@ static int ipc_plat_probe(struct platform_device *pdev)
> 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) {
> @@ -815,6 +774,15 @@ static int ipc_plat_probe(struct platform_device *pdev)
> return ret;
> }
>
> + /* GCR base address is at ipc_base + PLAT_RESOURCE_GCR_OFFSET */
> + ipcdev.gcr_regs = devm_regmap_init_mmio_clk(ipcdev.dev, NULL,
> + ipcdev.ipc_base + PLAT_RESOURCE_GCR_OFFSET,
> + &gcr_regmap_config);
> + if (IS_ERR(ipcdev.gcr_regs)) {
> + dev_err(ipcdev.dev, "gcr_regs regmap init failed\n");
> + return PTR_ERR(ipcdev.gcr_regs);
> + }
> +
> ret = ipc_create_pmc_devices(pdev);
> if (ret) {
> dev_err(&pdev->dev, "Failed to create PMC devices\n");
> @@ -836,8 +804,6 @@ static int ipc_plat_probe(struct platform_device *pdev)
> return ret;
> }
>
> - ipcdev.has_gcr_regs = true;
> -
> return 0;
> }
>
> --
> 2.7.4
>
--
With Best Regards,
Andy Shevchenko