drm/i915/hwmon: Expose card reactive critical power

Expose the card reactive critical (I1) power. I1 is exposed as
power1_crit in microwatts (typically for client products) or as
curr1_crit in milliamperes (typically for server).

v2: Add curr1_crit functionality (Ashutosh)
v3: Use HWMON_CHANNEL_INFO to define power1_crit, curr1_crit (Badal)
v4: Use hwm_ prefix for static functions (Ashutosh)
v5: KernelVersion: 6.2, Date: February 2023 in doc (Tvrtko)
v6: Change contact to intel-gfx (Rodrigo)

Cc: Sujaritha Sundaresan <sujaritha.sundaresan@intel.com>
Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: Badal Nilawar <badal.nilawar@intel.com>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Anshuman Gupta <anshuman.gupta@intel.com>
Signed-off-by: Anshuman Gupta <anshuman.gupta@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221013154526.2105579-6-ashutosh.dixit@intel.com

diff --git a/Documentation/ABI/testing/sysfs-driver-intel-i915-hwmon b/Documentation/ABI/testing/sysfs-driver-intel-i915-hwmon
index aa00c55..a7a6512 100644 (file)
--- a/Documentation/ABI/testing/sysfs-driver-intel-i915-hwmon
+++ b/Documentation/ABI/testing/sysfs-driver-intel-i915-hwmon
@@ -26,6 +26,32 @@ Description: RO. Card default power limit (default TDP setting).
 
                Only supported for particular Intel i915 graphics platforms.
 
+What:          /sys/devices/.../hwmon/hwmon<i>/power1_crit
+Date:          February 2023
+KernelVersion: 6.2
+Contact:       intel-gfx@lists.freedesktop.org
+Description:   RW. Card reactive critical (I1) power limit in microwatts.
+
+               Card reactive critical (I1) power limit in microwatts is exposed
+               for client products. The power controller will throttle the
+               operating frequency if the power averaged over a window exceeds
+               this limit.
+
+               Only supported for particular Intel i915 graphics platforms.
+
+What:          /sys/devices/.../hwmon/hwmon<i>/curr1_crit
+Date:          February 2023
+KernelVersion: 6.2
+Contact:       intel-gfx@lists.freedesktop.org
+Description:   RW. Card reactive critical (I1) power limit in milliamperes.
+
+               Card reactive critical (I1) power limit in milliamperes is
+               exposed for server products. The power controller will throttle
+               the operating frequency if the power averaged over a window
+               exceeds this limit.
+
+               Only supported for particular Intel i915 graphics platforms.
+
 What:          /sys/devices/.../hwmon/hwmon<i>/energy1_input
 Date:          February 2023
 KernelVersion: 6.2

diff --git a/drivers/gpu/drm/i915/i915_hwmon.c b/drivers/gpu/drm/i915/i915_hwmon.c
index d8d30da..2b24a7a 100644 (file)
--- a/drivers/gpu/drm/i915/i915_hwmon.c
+++ b/drivers/gpu/drm/i915/i915_hwmon.c
@@ -11,16 +11,19 @@
 #include "i915_hwmon.h"
 #include "i915_reg.h"
 #include "intel_mchbar_regs.h"
+#include "intel_pcode.h"
 #include "gt/intel_gt_regs.h"
 
 /*
  * SF_* - scale factors for particular quantities according to hwmon spec.
  * - voltage  - millivolts
  * - power  - microwatts
+ * - curr   - milliamperes
  * - energy - microjoules
  */
 #define SF_VOLTAGE     1000
 #define SF_POWER       1000000
+#define SF_CURR                1000
 #define SF_ENERGY      1000000
 
 struct hwm_reg {
@@ -158,11 +161,25 @@ hwm_energy(struct hwm_drvdata *ddat, long *energy)
 
 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),
+       HWMON_CHANNEL_INFO(power, HWMON_P_MAX | HWMON_P_RATED_MAX | HWMON_P_CRIT),
        HWMON_CHANNEL_INFO(energy, HWMON_E_INPUT),
+       HWMON_CHANNEL_INFO(curr, HWMON_C_CRIT),
        NULL
 };
 
+/* I1 is exposed as power_crit or as curr_crit depending on bit 31 */
+static int hwm_pcode_read_i1(struct drm_i915_private *i915, u32 *uval)
+{
+       return snb_pcode_read_p(&i915->uncore, PCODE_POWER_SETUP,
+                               POWER_SETUP_SUBCOMMAND_READ_I1, 0, uval);
+}
+
+static int hwm_pcode_write_i1(struct drm_i915_private *i915, u32 uval)
+{
+       return  snb_pcode_write_p(&i915->uncore, PCODE_POWER_SETUP,
+                                 POWER_SETUP_SUBCOMMAND_WRITE_I1, 0, uval);
+}
+
 static umode_t
 hwm_in_is_visible(const struct hwm_drvdata *ddat, u32 attr)
 {
@@ -198,13 +215,18 @@ 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 drm_i915_private *i915 = ddat->uncore->i915;
        struct i915_hwmon *hwmon = ddat->hwmon;
+       u32 uval;
 
        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;
+       case hwmon_power_crit:
+               return (hwm_pcode_read_i1(i915, &uval) ||
+                       !(uval & POWER_SETUP_I1_WATTS)) ? 0 : 0644;
        default:
                return 0;
        }
@@ -214,6 +236,8 @@ static int
 hwm_power_read(struct hwm_drvdata *ddat, u32 attr, int chan, long *val)
 {
        struct i915_hwmon *hwmon = ddat->hwmon;
+       int ret;
+       u32 uval;
 
        switch (attr) {
        case hwmon_power_max:
@@ -230,6 +254,15 @@ hwm_power_read(struct hwm_drvdata *ddat, u32 attr, int chan, long *val)
                                                hwmon->scl_shift_power,
                                                SF_POWER);
                return 0;
+       case hwmon_power_crit:
+               ret = hwm_pcode_read_i1(ddat->uncore->i915, &uval);
+               if (ret)
+                       return ret;
+               if (!(uval & POWER_SETUP_I1_WATTS))
+                       return -ENODEV;
+               *val = mul_u64_u32_shr(REG_FIELD_GET(POWER_SETUP_I1_DATA_MASK, uval),
+                                      SF_POWER, POWER_SETUP_I1_SHIFT);
+               return 0;
        default:
                return -EOPNOTSUPP;
        }
@@ -239,6 +272,7 @@ static int
 hwm_power_write(struct hwm_drvdata *ddat, u32 attr, int chan, long val)
 {
        struct i915_hwmon *hwmon = ddat->hwmon;
+       u32 uval;
 
        switch (attr) {
        case hwmon_power_max:
@@ -248,6 +282,9 @@ hwm_power_write(struct hwm_drvdata *ddat, u32 attr, int chan, long val)
                                          hwmon->scl_shift_power,
                                          SF_POWER, val);
                return 0;
+       case hwmon_power_crit:
+               uval = DIV_ROUND_CLOSEST_ULL(val << POWER_SETUP_I1_SHIFT, SF_POWER);
+               return hwm_pcode_write_i1(ddat->uncore->i915, uval);
        default:
                return -EOPNOTSUPP;
        }
@@ -280,6 +317,56 @@ hwm_energy_read(struct hwm_drvdata *ddat, u32 attr, long *val)
        }
 }
 
+static umode_t
+hwm_curr_is_visible(const struct hwm_drvdata *ddat, u32 attr)
+{
+       struct drm_i915_private *i915 = ddat->uncore->i915;
+       u32 uval;
+
+       switch (attr) {
+       case hwmon_curr_crit:
+               return (hwm_pcode_read_i1(i915, &uval) ||
+                       (uval & POWER_SETUP_I1_WATTS)) ? 0 : 0644;
+       default:
+               return 0;
+       }
+}
+
+static int
+hwm_curr_read(struct hwm_drvdata *ddat, u32 attr, long *val)
+{
+       int ret;
+       u32 uval;
+
+       switch (attr) {
+       case hwmon_curr_crit:
+               ret = hwm_pcode_read_i1(ddat->uncore->i915, &uval);
+               if (ret)
+                       return ret;
+               if (uval & POWER_SETUP_I1_WATTS)
+                       return -ENODEV;
+               *val = mul_u64_u32_shr(REG_FIELD_GET(POWER_SETUP_I1_DATA_MASK, uval),
+                                      SF_CURR, POWER_SETUP_I1_SHIFT);
+               return 0;
+       default:
+               return -EOPNOTSUPP;
+       }
+}
+
+static int
+hwm_curr_write(struct hwm_drvdata *ddat, u32 attr, long val)
+{
+       u32 uval;
+
+       switch (attr) {
+       case hwmon_curr_crit:
+               uval = DIV_ROUND_CLOSEST_ULL(val << POWER_SETUP_I1_SHIFT, SF_CURR);
+               return hwm_pcode_write_i1(ddat->uncore->i915, uval);
+       default:
+               return -EOPNOTSUPP;
+       }
+}
+
 static umode_t
 hwm_is_visible(const void *drvdata, enum hwmon_sensor_types type,
               u32 attr, int channel)
@@ -293,6 +380,8 @@ hwm_is_visible(const void *drvdata, enum hwmon_sensor_types type,
                return hwm_power_is_visible(ddat, attr, channel);
        case hwmon_energy:
                return hwm_energy_is_visible(ddat, attr);
+       case hwmon_curr:
+               return hwm_curr_is_visible(ddat, attr);
        default:
                return 0;
        }
@@ -311,6 +400,8 @@ hwm_read(struct device *dev, enum hwmon_sensor_types type, u32 attr,
                return hwm_power_read(ddat, attr, channel, val);
        case hwmon_energy:
                return hwm_energy_read(ddat, attr, val);
+       case hwmon_curr:
+               return hwm_curr_read(ddat, attr, val);
        default:
                return -EOPNOTSUPP;
        }
@@ -325,6 +416,8 @@ hwm_write(struct device *dev, enum hwmon_sensor_types type, u32 attr,
        switch (type) {
        case hwmon_power:
                return hwm_power_write(ddat, attr, channel, val);
+       case hwmon_curr:
+               return hwm_curr_write(ddat, attr, val);
        default:
                return -EOPNOTSUPP;
        }

diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index fc7b096..ab0823e 100644 (file)
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -6650,6 +6650,12 @@
 #define   DG1_PCODE_STATUS                     0x7E
 #define     DG1_UNCORE_GET_INIT_STATUS         0x0
 #define     DG1_UNCORE_INIT_STATUS_COMPLETE    0x1
+#define   PCODE_POWER_SETUP                    0x7C
+#define     POWER_SETUP_SUBCOMMAND_READ_I1     0x4
+#define     POWER_SETUP_SUBCOMMAND_WRITE_I1    0x5
+#define            POWER_SETUP_I1_WATTS                REG_BIT(31)
+#define            POWER_SETUP_I1_SHIFT                6       /* 10.6 fixed point format */
+#define            POWER_SETUP_I1_DATA_MASK            REG_GENMASK(15, 0)
 #define GEN12_PCODE_READ_SAGV_BLOCK_TIME_US    0x23
 #define   XEHP_PCODE_FREQUENCY_CONFIG          0x6e    /* xehpsdv, pvc */
 /* XEHP_PCODE_FREQUENCY_CONFIG sub-commands (param1) */