[Intel-gfx] [PATCH 5/7] drm/i915/hwmon: Expose card reactive critical power

Badal Nilawar
2022-09-26T17:50:28Z

From: Ashutosh Dixit <ashutosh.dixit@intel.com>

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)

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>
---
.../ABI/testing/sysfs-driver-intel-i915-hwmon | 26 +++++
drivers/gpu/drm/i915/i915_hwmon.c | 95 ++++++++++++++++++-
drivers/gpu/drm/i915/i915_reg.h | 6 ++
3 files changed, 126 insertions(+), 1 deletion(-)

diff --git a/Documentation/ABI/testing/sysfs-driver-intel-i915-hwmon b/Documentation/ABI/testing/sysfs-driver-intel-i915-hwmon
index 7525db243d74..f9d6d3b08bba 100644
--- 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/power1_crit
+Date: February 2023
+KernelVersion: 6.2
+Contact: dri-devel@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/curr1_crit
+Date: February 2023
+KernelVersion: 6.2
+Contact: dri-devel@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/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 9a49521b358a..2394fa789793 100644
--- 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 {
@@ -160,11 +163,25 @@ 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;
}
@@ -279,6 +316,56 @@ 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)
@@ -292,6 +379,8 @@ 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;
}
@@ -310,6 +399,8 @@ 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;
}
@@ -324,6 +415,8 @@ 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 5003a5ffbc6a..ff3b352c51cd 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -6655,6 +6655,12 @@
#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) */
--
2.25.1