The Stage 3 thermal threshold is currently configured during the controller initialization to 105 Celsius. From the kernel perspective, this configuration is harmful because: * The stage 3 interrupt that gets triggered when the threshold is crossed is not handled in any way by the IRQ handler, it just gets cleared. Besides, the temperature used for stage 3 comes from the sensors, and the critical thermal trip points described in the Devicetree will already cause a shutdown when crossed (at a lower temperature, of 100 Celsius, for all SoCs currently using this driver). * The only effect of crossing the stage 3 threshold that has been observed is that it causes the machine to no longer be able to enter suspend. Even if that was a result of a momentary glitch in the temperature reading of a sensor (as has been observed on the MT8192-based Chromebooks).
For those reasons, disable the Stage 3 thermal threshold configuration.
Cc: stable@vger.kernel.org Reported-by: Hsin-Te Yuan yuanhsinte@chromium.org Closes: https://lore.kernel.org/all/20241108-lvts-v1-1-eee339c6ca20@chromium.org/ Fixes: f5f633b18234 ("thermal/drivers/mediatek: Add the Low Voltage Thermal Sensor driver") Reviewed-by: AngeloGioacchino Del Regno angelogioacchino.delregno@collabora.com Signed-off-by: Nícolas F. R. A. Prado nfraprado@collabora.com --- drivers/thermal/mediatek/lvts_thermal.c | 16 ++-------------- 1 file changed, 2 insertions(+), 14 deletions(-)
diff --git a/drivers/thermal/mediatek/lvts_thermal.c b/drivers/thermal/mediatek/lvts_thermal.c index a1a438ebad33c1fff8ca9781e12ef9e278eef785..0aaa44b734ca43e6abfd97b2ca4ce34dc6f15826 100644 --- a/drivers/thermal/mediatek/lvts_thermal.c +++ b/drivers/thermal/mediatek/lvts_thermal.c @@ -65,7 +65,7 @@ #define LVTS_HW_FILTER 0x0 #define LVTS_TSSEL_CONF 0x13121110 #define LVTS_CALSCALE_CONF 0x300 -#define LVTS_MONINT_CONF 0x8300318C +#define LVTS_MONINT_CONF 0x0300318C
#define LVTS_MONINT_OFFSET_SENSOR0 0xC #define LVTS_MONINT_OFFSET_SENSOR1 0x180 @@ -91,8 +91,6 @@ #define LVTS_MSR_READ_TIMEOUT_US 400 #define LVTS_MSR_READ_WAIT_US (LVTS_MSR_READ_TIMEOUT_US / 2)
-#define LVTS_HW_TSHUT_TEMP 105000 - #define LVTS_MINIMUM_THRESHOLD 20000
static int golden_temp = LVTS_GOLDEN_TEMP_DEFAULT; @@ -145,7 +143,6 @@ struct lvts_ctrl { struct lvts_sensor sensors[LVTS_SENSOR_MAX]; const struct lvts_data *lvts_data; u32 calibration[LVTS_SENSOR_MAX]; - u32 hw_tshut_raw_temp; u8 valid_sensor_mask; int mode; void __iomem *base; @@ -837,14 +834,6 @@ static int lvts_ctrl_init(struct device *dev, struct lvts_domain *lvts_td, */ lvts_ctrl[i].mode = lvts_data->lvts_ctrl[i].mode;
- /* - * The temperature to raw temperature must be done - * after initializing the calibration. - */ - lvts_ctrl[i].hw_tshut_raw_temp = - lvts_temp_to_raw(LVTS_HW_TSHUT_TEMP, - lvts_data->temp_factor); - lvts_ctrl[i].low_thresh = INT_MIN; lvts_ctrl[i].high_thresh = INT_MIN; } @@ -919,7 +908,6 @@ static int lvts_irq_init(struct lvts_ctrl *lvts_ctrl) * 10 : Selected sensor with bits 19-18 * 11 : Reserved */ - writel(BIT(16), LVTS_PROTCTL(lvts_ctrl->base));
/* * LVTS_PROTTA : Stage 1 temperature threshold @@ -932,8 +920,8 @@ static int lvts_irq_init(struct lvts_ctrl *lvts_ctrl) * * writel(0x0, LVTS_PROTTA(lvts_ctrl->base)); * writel(0x0, LVTS_PROTTB(lvts_ctrl->base)); + * writel(0x0, LVTS_PROTTC(lvts_ctrl->base)); */ - writel(lvts_ctrl->hw_tshut_raw_temp, LVTS_PROTTC(lvts_ctrl->base));
/* * LVTS_MONINT : Interrupt configuration register