1 files changed, 29 insertions, 0 deletions

diff --git a/drivers/gpu/drm/xe/xe_hwmon.c b/drivers/gpu/drm/xe/xe_hwmon.c
index f08fc4377d25..c17ed1ae8649 100644
--- a/drivers/gpu/drm/xe/xe_hwmon.c
+++ b/drivers/gpu/drm/xe/xe_hwmon.c
@@ -332,6 +332,7 @@ static int xe_hwmon_power_max_write(struct xe_hwmon *hwmon, u32 attr, int channe
 	int ret = 0;
 	u32 reg_val, max;
 	struct xe_reg rapl_limit;
+	u64 max_supp_power_limit = 0;
 
 	mutex_lock(&hwmon->hwmon_lock);
 
@@ -356,6 +357,20 @@ static int xe_hwmon_power_max_write(struct xe_hwmon *hwmon, u32 attr, int channe
 		goto unlock;
 	}
 
+	/*
+	 * If the sysfs value exceeds the maximum pcode supported power limit value, clamp it to
+	 * the supported maximum (U12.3 format).
+	 * This is to avoid truncation during reg_val calculation below and ensure the valid
+	 * power limit is sent for pcode which would clamp it to card-supported value.
+	 */
+	max_supp_power_limit = ((PWR_LIM_VAL) >> hwmon->scl_shift_power) * SF_POWER;
+	if (value > max_supp_power_limit) {
+		value = max_supp_power_limit;
+		drm_info(&hwmon->xe->drm,
+			 "Power limit clamped as selected %s exceeds channel %d limit\n",
+			 PWR_ATTR_TO_STR(attr), channel);
+	}
+
 	/* Computation in 64-bits to avoid overflow. Round to nearest. */
 	reg_val = DIV_ROUND_CLOSEST_ULL((u64)value << hwmon->scl_shift_power, SF_POWER);
 
@@ -739,9 +754,23 @@ static int xe_hwmon_power_curr_crit_write(struct xe_hwmon *hwmon, int channel,
 {
 	int ret;
 	u32 uval;
+	u64 max_crit_power_curr = 0;
 
 	mutex_lock(&hwmon->hwmon_lock);
 
+	/*
+	 * If the sysfs value exceeds the pcode mailbox cmd POWER_SETUP_SUBCOMMAND_WRITE_I1
+	 * max supported value, clamp it to the command's max (U10.6 format).
+	 * This is to avoid truncation during uval calculation below and ensure the valid power
+	 * limit is sent for pcode which would clamp it to card-supported value.
+	 */
+	max_crit_power_curr = (POWER_SETUP_I1_DATA_MASK >> POWER_SETUP_I1_SHIFT) * scale_factor;
+	if (value > max_crit_power_curr) {
+		value = max_crit_power_curr;
+		drm_info(&hwmon->xe->drm,
+			 "Power limit clamped as selected exceeds channel %d limit\n",
+			 channel);
+	}
 	uval = DIV_ROUND_CLOSEST_ULL(value << POWER_SETUP_I1_SHIFT, scale_factor);
 	ret = xe_hwmon_pcode_write_i1(hwmon, uval);