| Message ID | 20230706153823.201943-6-nfraprado@collabora.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | thermal/drivers/mediatek/lvts_thermal: Fixes to the interrupt handling | expand |
Il 06/07/23 17:37, Nícolas F. R. A. Prado ha scritto: > The thermal framework might leave the low threshold unset if there > aren't any lower trip points. This leaves the register zeroed, which > translates to a very high temperature for the low threshold. The > interrupt for this threshold is then immediately triggered, and the > state machine gets stuck, preventing any other temperature monitoring > interrupts to ever trigger. > > (The same happens by not setting the Cold or Hot to Normal thresholds > when using those) > > Set the unused threshold to a valid low value. This value was chosen so > that for any valid golden temperature read from the efuse, when the > value is converted to raw and back again to milliCelsius, the result > doesn't underflow. > > Fixes: f5f633b18234 ("thermal/drivers/mediatek: Add the Low Voltage Thermal Sensor driver") > Signed-off-by: Nícolas F. R. A. Prado <nfraprado@collabora.com> > Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
On 06/07/2023 17:37, Nícolas F. R. A. Prado wrote: > The thermal framework might leave the low threshold unset if there > aren't any lower trip points. This leaves the register zeroed, which > translates to a very high temperature for the low threshold. The > interrupt for this threshold is then immediately triggered, and the > state machine gets stuck, preventing any other temperature monitoring > interrupts to ever trigger. > > (The same happens by not setting the Cold or Hot to Normal thresholds > when using those) > > Set the unused threshold to a valid low value. This value was chosen so > that for any valid golden temperature read from the efuse, when the > value is converted to raw and back again to milliCelsius, the result > doesn't underflow. Reviewed-by: Alexandre Mergnat <amergnat@baylibre.com>
diff --git a/drivers/thermal/mediatek/lvts_thermal.c b/drivers/thermal/mediatek/lvts_thermal.c index e6dd4d120e54..7552e1d59dc9 100644 --- a/drivers/thermal/mediatek/lvts_thermal.c +++ b/drivers/thermal/mediatek/lvts_thermal.c @@ -83,6 +83,8 @@ #define LVTS_HW_SHUTDOWN_MT8195 105000 +#define LVTS_MINIMUM_THRESHOLD 20000 + static int golden_temp = LVTS_GOLDEN_TEMP_DEFAULT; static int coeff_b = LVTS_COEFF_B; @@ -294,7 +296,7 @@ static int lvts_set_trips(struct thermal_zone_device *tz, int low, int high) { struct lvts_sensor *lvts_sensor = thermal_zone_device_priv(tz); void __iomem *base = lvts_sensor->base; - u32 raw_low = lvts_temp_to_raw(low); + u32 raw_low = lvts_temp_to_raw(low != -INT_MAX ? low : LVTS_MINIMUM_THRESHOLD); u32 raw_high = lvts_temp_to_raw(high); /* @@ -306,11 +308,9 @@ static int lvts_set_trips(struct thermal_zone_device *tz, int low, int high) * * 14-0 : Raw temperature for threshold */ - if (low != -INT_MAX) { - pr_debug("%s: Setting low limit temperature interrupt: %d\n", - thermal_zone_device_type(tz), low); - writel(raw_low, LVTS_OFFSETL(base)); - } + pr_debug("%s: Setting low limit temperature interrupt: %d\n", + thermal_zone_device_type(tz), low); + writel(raw_low, LVTS_OFFSETL(base)); /* * High offset temperature threshold
The thermal framework might leave the low threshold unset if there aren't any lower trip points. This leaves the register zeroed, which translates to a very high temperature for the low threshold. The interrupt for this threshold is then immediately triggered, and the state machine gets stuck, preventing any other temperature monitoring interrupts to ever trigger. (The same happens by not setting the Cold or Hot to Normal thresholds when using those) Set the unused threshold to a valid low value. This value was chosen so that for any valid golden temperature read from the efuse, when the value is converted to raw and back again to milliCelsius, the result doesn't underflow. Fixes: f5f633b18234 ("thermal/drivers/mediatek: Add the Low Voltage Thermal Sensor driver") Signed-off-by: Nícolas F. R. A. Prado <nfraprado@collabora.com> --- Changes in v3: - Converted MINIMUM_THRESHOLD earlier to eliminate need for extra branch - Fixed typo: MINIUM -> MINIMUM Changes in v2: - Added this commit drivers/thermal/mediatek/lvts_thermal.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-)