[PATCH] hwmon: (k10temp): Check range scale when CUR_TEMP register is read-write

From: Babu Moger
Date: Thu Apr 13 2023 - 17:40:19 EST


From: Babu Moger <Babu.Moger@xxxxxxx>

Spec says, when CUR_TEMP_TJ_SEL == 3 and CUR_TEMP_RANGE_SEL == 0,
it should use RangeUnadjusted is 0, which is (CurTmp*0.125 -49) C. The
CUR_TEMP register is read-write when CUR_TEMP_TJ_SEL == 3 (bit 17-16).

Add the check to detect it.

Sensors command's output before the patch.
$sensors
k10temp-pci-00c3
Adapter: PCI adapter
Tctl: +76.6°C <- Wrong value
Tccd1: +26.5°C
Tccd2: +27.5°C
Tccd3: +27.2°C
Tccd4: +27.5°C
Tccd5: +26.0°C
Tccd6: +26.2°C
Tccd7: +25.0°C
Tccd8: +26.5°C

Sensors command's output after the patch.
$sensors
k10temp-pci-00c3
Adapter: PCI adapter
Tctl: +28.8°C <- corrected value
Tccd1: +27.5°C
Tccd2: +28.5°C
Tccd3: +28.5°C
Tccd4: +28.5°C
Tccd5: +27.0°C
Tccd6: +27.5°C
Tccd7: +27.0°C
Tccd8: +27.5°C

Signed-off-by: Babu Moger <babu.moger@xxxxxxx>
---
drivers/hwmon/k10temp.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/hwmon/k10temp.c b/drivers/hwmon/k10temp.c
index 5a9d47a229e4..be8bbb1c3a02 100644
--- a/drivers/hwmon/k10temp.c
+++ b/drivers/hwmon/k10temp.c
@@ -75,6 +75,7 @@ static DEFINE_MUTEX(nb_smu_ind_mutex);

#define ZEN_CUR_TEMP_SHIFT 21
#define ZEN_CUR_TEMP_RANGE_SEL_MASK BIT(19)
+#define ZEN_CUR_TEMP_TJ_SEL_MASK GENMASK(17, 16)

struct k10temp_data {
struct pci_dev *pdev;
@@ -155,7 +156,8 @@ static long get_raw_temp(struct k10temp_data *data)

data->read_tempreg(data->pdev, &regval);
temp = (regval >> ZEN_CUR_TEMP_SHIFT) * 125;
- if (regval & data->temp_adjust_mask)
+ if ((regval & data->temp_adjust_mask) ||
+ (regval & ZEN_CUR_TEMP_TJ_SEL_MASK) == ZEN_CUR_TEMP_TJ_SEL_MASK)
temp -= 49000;
return temp;
}
--
2.34.1