Re: [Intel-gfx] [PATCH 3/7] drm/i915/hwmon: Power PL1 limit and TDP setting

Gupta, Anshuman
2022-09-28T07:09:16Z

On 9/27/2022 11:20 AM, Badal Nilawar wrote:
> From: Dale B Stimson <dale.b.stimson@intel.com>
>
> Use i915 HWMON to display/modify dGfx power PL1 limit and TDP setting.
>
> v2:
> - Fix review comments (Ashutosh)
> - Do not restore power1_max upon module unload/load sequence
> because on production systems modules are always loaded
> and not unloaded/reloaded (Ashutosh)
> - Fix review comments (Jani)
> - Remove endianness conversion (Ashutosh)
> v3: Add power1_rated_max (Ashutosh)
> v4:
> - Use macro HWMON_CHANNEL_INFO to define power channel (Guenter)
> - Update the date and kernel version in Documentation (Badal)
> v5: Use hwm_ prefix for static functions (Ashutosh)
> v6: Fix review comments (Ashutosh)
> v7:
> - Define PCU_PACKAGE_POWER_SKU for DG1,DG2 and move
> PKG_PKG_TDP to intel_mchbar_regs.h (Anshuman)
> - KernelVersion: 6.2, Date: February 2023 in doc (Tvrtko)
>
> Cc: Guenter Roeck <linux@roeck-us.net>
> Signed-off-by: Dale B Stimson <dale.b.stimson@intel.com>
> Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
> Signed-off-by: Riana Tauro <riana.tauro@intel.com>
> Signed-off-by: Badal Nilawar <badal.nilawar@intel.com>
> Acked-by: Guenter Roeck <linux@roeck-us.net>
> Reviewed-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
LGTM,
Reviewed-by: Anshuman Gupta <anshuman.gupta@intel.com>
> ---
> .../ABI/testing/sysfs-driver-intel-i915-hwmon | 20 +++
> drivers/gpu/drm/i915/i915_hwmon.c | 158 +++++++++++++++++-
> drivers/gpu/drm/i915/intel_mchbar_regs.h | 12 ++
> 3 files changed, 188 insertions(+), 2 deletions(-)
>
> diff --git a/Documentation/ABI/testing/sysfs-driver-intel-i915-hwmon b/Documentation/ABI/testing/sysfs-driver-intel-i915-hwmon
> index cd9554c1a4f8..16e697b1db3d 100644
> --- a/Documentation/ABI/testing/sysfs-driver-intel-i915-hwmon
> +++ b/Documentation/ABI/testing/sysfs-driver-intel-i915-hwmon
> @@ -5,3 +5,23 @@ Contact: dri-devel@lists.freedesktop.org
> Description: RO. Current Voltage in millivolt.
>
> Only supported for particular Intel i915 graphics platforms.
> +
> +What: /sys/devices/.../hwmon/hwmon/power1_max
> +Date: February 2023
> +KernelVersion: 6.2
> +Contact: dri-devel@lists.freedesktop.org
> +Description: RW. Card reactive sustained (PL1/Tau) power limit in microwatts.
> +
> + The power controller will throttle the operating frequency
> + if the power averaged over a window (typically seconds)
> + exceeds this limit.
> +
> + Only supported for particular Intel i915 graphics platforms.
> +
> +What: /sys/devices/.../hwmon/hwmon/power1_rated_max
> +Date: February 2023
> +KernelVersion: 6.2
> +Contact: dri-devel@lists.freedesktop.org
> +Description: RO. Card default power limit (default TDP setting).
> +
> + Only supported for particular Intel i915 graphics platforms.
> diff --git a/drivers/gpu/drm/i915/i915_hwmon.c b/drivers/gpu/drm/i915/i915_hwmon.c
> index 9fcff6a884ee..53d34a7a86f7 100644
> --- a/drivers/gpu/drm/i915/i915_hwmon.c
> +++ b/drivers/gpu/drm/i915/i915_hwmon.c
> @@ -16,11 +16,16 @@
> /*
> * SF_* - scale factors for particular quantities according to hwmon spec.
> * - voltage - millivolts
> + * - power - microwatts
> */
> #define SF_VOLTAGE 1000
> +#define SF_POWER 1000000
>
> struct hwm_reg {
> i915_reg_t gt_perf_status;
> + i915_reg_t pkg_power_sku_unit;
> + i915_reg_t pkg_power_sku;
> + i915_reg_t pkg_rapl_limit;
> };
>
> struct hwm_drvdata {
> @@ -34,10 +39,68 @@ struct i915_hwmon {
> struct hwm_drvdata ddat;
> struct mutex hwmon_lock; /* counter overflow logic and rmw */
> struct hwm_reg rg;
> + int scl_shift_power;
> };
>
> +static void
> +hwm_locked_with_pm_intel_uncore_rmw(struct hwm_drvdata *ddat,
> + i915_reg_t reg, u32 clear, u32 set)
> +{
> + struct i915_hwmon *hwmon = ddat->hwmon;
> + struct intel_uncore *uncore = ddat->uncore;
> + intel_wakeref_t wakeref;
> +
> + mutex_lock(&hwmon->hwmon_lock);
> +
> + with_intel_runtime_pm(uncore->rpm, wakeref)
> + intel_uncore_rmw(uncore, reg, clear, set);
> +
> + mutex_unlock(&hwmon->hwmon_lock);
> +}
> +
> +/*
> + * This function's return type of u64 allows for the case where the scaling
> + * of the field taken from the 32-bit register value might cause a result to
> + * exceed 32 bits.
> + */
> +static u64
> +hwm_field_read_and_scale(struct hwm_drvdata *ddat, i915_reg_t rgadr,
> + u32 field_msk, int nshift, u32 scale_factor)
> +{
> + struct intel_uncore *uncore = ddat->uncore;
> + intel_wakeref_t wakeref;
> + u32 reg_value;
> +
> + with_intel_runtime_pm(uncore->rpm, wakeref)
> + reg_value = intel_uncore_read(uncore, rgadr);
> +
> + reg_value = REG_FIELD_GET(field_msk, reg_value);
> +
> + return mul_u64_u32_shr(reg_value, scale_factor, nshift);
> +}
> +
> +static void
> +hwm_field_scale_and_write(struct hwm_drvdata *ddat, i915_reg_t rgadr,
> + u32 field_msk, int nshift,
> + unsigned int scale_factor, long lval)
> +{
> + u32 nval;
> + u32 bits_to_clear;
> + u32 bits_to_set;
> +
> + /* Computation in 64-bits to avoid overflow. Round to nearest. */
> + nval = DIV_ROUND_CLOSEST_ULL((u64)lval << nshift, scale_factor);
> +
> + bits_to_clear = field_msk;
> + bits_to_set = FIELD_PREP(field_msk, nval);
> +
> + hwm_locked_with_pm_intel_uncore_rmw(ddat, rgadr,
> + bits_to_clear, bits_to_set);
> +}
> +
> static const struct hwmon_channel_info *hwm_info[] = {
> HWMON_CHANNEL_INFO(in, HWMON_I_INPUT),
> + HWMON_CHANNEL_INFO(power, HWMON_P_MAX | HWMON_P_RATED_MAX),
> NULL
> };
>
> @@ -71,6 +134,64 @@ hwm_in_read(struct hwm_drvdata *ddat, u32 attr, long *val)
> }
> }
>
> +static umode_t
> +hwm_power_is_visible(const struct hwm_drvdata *ddat, u32 attr, int chan)
> +{
> + struct i915_hwmon *hwmon = ddat->hwmon;
> +
> + switch (attr) {
> + case hwmon_power_max:
> + return i915_mmio_reg_valid(hwmon->rg.pkg_rapl_limit) ? 0664 : 0;
> + case hwmon_power_rated_max:
> + return i915_mmio_reg_valid(hwmon->rg.pkg_power_sku) ? 0444 : 0;
> + default:
> + return 0;
> + }
> +}
> +
> +static int
> +hwm_power_read(struct hwm_drvdata *ddat, u32 attr, int chan, long *val)
> +{
> + struct i915_hwmon *hwmon = ddat->hwmon;
> +
> + switch (attr) {
> + case hwmon_power_max:
> + *val = hwm_field_read_and_scale(ddat,
> + hwmon->rg.pkg_rapl_limit,
> + PKG_PWR_LIM_1,
> + hwmon->scl_shift_power,
> + SF_POWER);
> + return 0;
> + case hwmon_power_rated_max:
> + *val = hwm_field_read_and_scale(ddat,
> + hwmon->rg.pkg_power_sku,
> + PKG_PKG_TDP,
> + hwmon->scl_shift_power,
> + SF_POWER);
> + return 0;
> + default:
> + return -EOPNOTSUPP;
> + }
> +}
> +
> +static int
> +hwm_power_write(struct hwm_drvdata *ddat, u32 attr, int chan, long val)
> +{
> + struct i915_hwmon *hwmon = ddat->hwmon;
> +
> + switch (attr) {
> + case hwmon_power_max:
> + hwm_field_scale_and_write(ddat,
> + hwmon->rg.pkg_rapl_limit,
> + PKG_PWR_LIM_1,
> + hwmon->scl_shift_power,
> + SF_POWER, val);
> + return 0;
> + default:
> + return -EOPNOTSUPP;
> + }
> +}
> +
> static umode_t
> hwm_is_visible(const void *drvdata, enum hwmon_sensor_types type,
> u32 attr, int channel)
> @@ -80,6 +201,8 @@ hwm_is_visible(const void *drvdata, enum hwmon_sensor_types type,
> switch (type) {
> case hwmon_in:
> return hwm_in_is_visible(ddat, attr);
> + case hwmon_power:
> + return hwm_power_is_visible(ddat, attr, channel);
> default:
> return 0;
> }
> @@ -94,6 +217,8 @@ hwm_read(struct device *dev, enum hwmon_sensor_types type, u32 attr,
> switch (type) {
> case hwmon_in:
> return hwm_in_read(ddat, attr, val);
> + case hwmon_power:
> + return hwm_power_read(ddat, attr, channel, val);
> default:
> return -EOPNOTSUPP;
> }
> @@ -103,7 +228,11 @@ static int
> hwm_write(struct device *dev, enum hwmon_sensor_types type, u32 attr,
> int channel, long val)
> {
> + struct hwm_drvdata *ddat = dev_get_drvdata(dev);
> +
> switch (type) {
> + case hwmon_power:
> + return hwm_power_write(ddat, attr, channel, val);
> default:
> return -EOPNOTSUPP;
> }
> @@ -124,11 +253,36 @@ static void
> hwm_get_preregistration_info(struct drm_i915_private *i915)
> {
> struct i915_hwmon *hwmon = i915->hwmon;
> + struct intel_uncore *uncore = &i915->uncore;
> + intel_wakeref_t wakeref;
> + u32 val_sku_unit;
>
> - if (IS_DG1(i915) || IS_DG2(i915))
> + if (IS_DG1(i915) || IS_DG2(i915)) {
> hwmon->rg.gt_perf_status = GEN12_RPSTAT1;
> - else
> + hwmon->rg.pkg_power_sku_unit = PCU_PACKAGE_POWER_SKU_UNIT;
> + hwmon->rg.pkg_power_sku = PCU_PACKAGE_POWER_SKU;
> + hwmon->rg.pkg_rapl_limit = PCU_PACKAGE_RAPL_LIMIT;
> + } else {
> hwmon->rg.gt_perf_status = INVALID_MMIO_REG;
> + hwmon->rg.pkg_power_sku_unit = INVALID_MMIO_REG;
> + hwmon->rg.pkg_power_sku = INVALID_MMIO_REG;
> + hwmon->rg.pkg_rapl_limit = INVALID_MMIO_REG;
> + }
> +
> + with_intel_runtime_pm(uncore->rpm, wakeref) {
> + /*
> + * The contents of register hwmon->rg.pkg_power_sku_unit do not change,
> + * so read it once and store the shift values.
> + */
> + if (i915_mmio_reg_valid(hwmon->rg.pkg_power_sku_unit)) {
> + val_sku_unit = intel_uncore_read(uncore,
> + hwmon->rg.pkg_power_sku_unit);
> + } else {
> + val_sku_unit = 0;
> + }
> +
> + hwmon->scl_shift_power = REG_FIELD_GET(PKG_PWR_UNIT, val_sku_unit);
> + }
> }
>
> void i915_hwmon_register(struct drm_i915_private *i915)
> diff --git a/drivers/gpu/drm/i915/intel_mchbar_regs.h b/drivers/gpu/drm/i915/intel_mchbar_regs.h
> index ffc702b79579..d7e2e4711792 100644
> --- a/drivers/gpu/drm/i915/intel_mchbar_regs.h
> +++ b/drivers/gpu/drm/i915/intel_mchbar_regs.h
> @@ -189,6 +189,16 @@
> #define DG1_QCLK_RATIO_MASK REG_GENMASK(9, 2)
> #define DG1_QCLK_REFERENCE REG_BIT(10)
>
> +/*
> + * *_PACKAGE_POWER_SKU - SKU power and timing parameters.
> + */
> +#define PCU_PACKAGE_POWER_SKU _MMIO(MCHBAR_MIRROR_BASE_SNB + 0x5930)
> +#define PKG_PKG_TDP GENMASK_ULL(14, 0)
> +
> +#define PCU_PACKAGE_POWER_SKU_UNIT _MMIO(MCHBAR_MIRROR_BASE_SNB + 0x5938)
> +#define PKG_PWR_UNIT REG_GENMASK(3, 0)
> +#define PKG_TIME_UNIT REG_GENMASK(19, 16)
> +
> #define GEN6_GT_PERF_STATUS _MMIO(MCHBAR_MIRROR_BASE_SNB + 0x5948)
> #define GEN6_RP_STATE_LIMITS _MMIO(MCHBAR_MIRROR_BASE_SNB + 0x5994)
> #define GEN6_RP_STATE_CAP _MMIO(MCHBAR_MIRROR_BASE_SNB + 0x5998)
> @@ -198,6 +208,8 @@
>
> #define GEN10_FREQ_INFO_REC _MMIO(MCHBAR_MIRROR_BASE_SNB + 0x5ef0)
> #define RPE_MASK REG_GENMASK(15, 8)
> +#define PCU_PACKAGE_RAPL_LIMIT _MMIO(MCHBAR_MIRROR_BASE_SNB + 0x59a0)
> +#define PKG_PWR_LIM_1 REG_GENMASK(14, 0)
>
> /* snb MCH registers for priority tuning */
> #define MCH_SSKPD _MMIO(MCHBAR_MIRROR_BASE_SNB + 0x5d10)