From: Dale B Stimson <dale.b.stimson@xxxxxxxxx>
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)
- Update date, kernel version in documentation
Cc: Guenter Roeck <linux@xxxxxxxxxxxx>
Signed-off-by: Dale B Stimson <dale.b.stimson@xxxxxxxxx>
Signed-off-by: Ashutosh Dixit <ashutosh.dixit@xxxxxxxxx>
Signed-off-by: Riana Tauro <riana.tauro@xxxxxxxxx>
Signed-off-by: Badal Nilawar <badal.nilawar@xxxxxxxxx>
Acked-by: Guenter Roeck <linux@xxxxxxxxxxxx>
---
.../ABI/testing/sysfs-driver-intel-i915-hwmon | 20 +++
drivers/gpu/drm/i915/i915_hwmon.c | 158 +++++++++++++++++-
drivers/gpu/drm/i915/i915_reg.h | 5 +
drivers/gpu/drm/i915/intel_mchbar_regs.h | 6 +
4 files changed, 187 insertions(+), 2 deletions(-)
diff --git a/Documentation/ABI/testing/sysfs-driver-intel-i915-hwmon
b/Documentation/ABI/testing/sysfs-driver-intel-i915-hwmon
index e2974f928e58..bc061238e35c 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@xxxxxxxxxxxxxxxxxxxxx
Description: RO. Current Voltage in millivolt.
Only supported for particular Intel i915 graphics platforms.
+
+What: /sys/devices/.../hwmon/hwmon<i>/power1_max
+Date: September 2022
+KernelVersion: 6
+Contact: dri-devel@xxxxxxxxxxxxxxxxxxxxx
+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<i>/power1_rated_max
+Date: September 2022
+KernelVersion: 6
+Contact: dri-devel@xxxxxxxxxxxxxxxxxxxxx
+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 45745afa5c5b..5183cf51a49b 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,It seems a dead code,
pkg_power_sky register in initialized with
