[PATCH] drm/xe/hwmon: Update xe hwmon with couple of fixes

From: Karthik Poosa <karthik.poosa@intel.com>
To: intel-xe@lists.freedesktop.org
Cc: anshuman.gupta@intel.com, badal.nilawar@intel.com,
	rodrigo.vivi@intel.com, Karthik Poosa <karthik.poosa@intel.com>
Subject: [PATCH] drm/xe/hwmon: Update xe hwmon with couple of fixes
Date: Thu, 28 Mar 2024 19:32:22 +0530	[thread overview]
Message-ID: <20240328140222.3796853-1-karthik.poosa@intel.com> (raw)

Fix potential overflows with upcasting.
Initialize variables which were being used uninitialized.

Fixes: 4446fcf220ce ("drm/xe/hwmon: Expose power1_max_interval")
Signed-off-by: Karthik Poosa <karthik.poosa@intel.com>
---
 drivers/gpu/drm/xe/xe_hwmon.c | 18 +++++++++---------
 1 file changed, 9 insertions(+), 9 deletions(-)

diff --git a/drivers/gpu/drm/xe/xe_hwmon.c b/drivers/gpu/drm/xe/xe_hwmon.c
index a256af8c2012..6ed9d5c4f6b1 100644
--- a/drivers/gpu/drm/xe/xe_hwmon.c
+++ b/drivers/gpu/drm/xe/xe_hwmon.c
@@ -153,7 +153,7 @@ static void xe_hwmon_process_reg(struct xe_hwmon *hwmon, enum xe_hwmon_reg hwmon
  */
 static void xe_hwmon_power_max_read(struct xe_hwmon *hwmon, long *value)
 {
-	u64 reg_val, min, max;
+	u64 reg_val = 0, min, max;
 
 	mutex_lock(&hwmon->hwmon_lock);
 
@@ -182,7 +182,7 @@ static void xe_hwmon_power_max_read(struct xe_hwmon *hwmon, long *value)
 static int xe_hwmon_power_max_write(struct xe_hwmon *hwmon, long value)
 {
 	int ret = 0;
-	u64 reg_val;
+	u64 reg_val = 0;
 
 	mutex_lock(&hwmon->hwmon_lock);
 
@@ -212,7 +212,7 @@ static int xe_hwmon_power_max_write(struct xe_hwmon *hwmon, long value)
 
 static void xe_hwmon_power_rated_max_read(struct xe_hwmon *hwmon, long *value)
 {
-	u64 reg_val;
+	u64 reg_val = 0;
 
 	xe_hwmon_process_reg(hwmon, REG_PKG_POWER_SKU, REG_READ32, &reg_val, 0, 0);
 	reg_val = REG_FIELD_GET(PKG_TDP, reg_val);
@@ -243,7 +243,7 @@ static void
 xe_hwmon_energy_get(struct xe_hwmon *hwmon, long *energy)
 {
 	struct xe_hwmon_energy_info *ei = &hwmon->ei;
-	u64 reg_val;
+	u64 reg_val = 0;
 
 	xe_hwmon_process_reg(hwmon, REG_PKG_ENERGY_STATUS, REG_READ32,
 			     &reg_val, 0, 0);
@@ -264,8 +264,8 @@ xe_hwmon_power1_max_interval_show(struct device *dev, struct device_attribute *a
 				  char *buf)
 {
 	struct xe_hwmon *hwmon = dev_get_drvdata(dev);
-	u32 x, y, x_w = 2; /* 2 bits */
-	u64 r, tau4, out;
+	u32 x = 0, y = 0, x_w = 2; /* 2 bits */
+	u64 r = 0, tau4, out;
 
 	xe_pm_runtime_get(gt_to_xe(hwmon->gt));
 
@@ -291,7 +291,7 @@ xe_hwmon_power1_max_interval_show(struct device *dev, struct device_attribute *a
 	 * As y can be < 2, we compute tau4 = (4 | x) << y
 	 * and then add 2 when doing the final right shift to account for units
 	 */
-	tau4 = ((1 << x_w) | x) << y;
+	tau4 = (u64)((1 << x_w) | x) << y;
 
 	/* val in hwmon interface units (millisec) */
 	out = mul_u64_u32_shr(tau4, SF_TIME, hwmon->scl_shift_time + x_w);
@@ -331,7 +331,7 @@ xe_hwmon_power1_max_interval_store(struct device *dev, struct device_attribute *
 	r = FIELD_PREP(PKG_MAX_WIN, PKG_MAX_WIN_DEFAULT);
 	x = REG_FIELD_GET(PKG_MAX_WIN_X, r);
 	y = REG_FIELD_GET(PKG_MAX_WIN_Y, r);
-	tau4 = ((1 << x_w) | x) << y;
+	tau4 = (u64)((1 << x_w) | x) << y;
 	max_win = mul_u64_u32_shr(tau4, SF_TIME, hwmon->scl_shift_time + x_w);
 
 	if (val > max_win)
@@ -466,7 +466,7 @@ static int xe_hwmon_power_curr_crit_write(struct xe_hwmon *hwmon, long value, u3
 
 static void xe_hwmon_get_voltage(struct xe_hwmon *hwmon, long *value)
 {
-	u64 reg_val;
+	u64 reg_val = 0;
 
 	xe_hwmon_process_reg(hwmon, REG_GT_PERF_STATUS,
 			     REG_READ32, &reg_val, 0, 0);
-- 
2.25.1

