[STABLE 5.15][PATCH] thermal: devfreq_cooling: Fix perf state when calculate dfc res_util

[Lukasz Luba]

From: Ye Zhang <ye.zhang@xxxxxxxxxxxxxx>

The issue occurs when the devfreq cooling device uses the EM power model
and the get_real_power() callback is provided by the driver.

The EM power table is sorted ascending，can't index the table by cooling
device state，so convert cooling state to performance state by
dfc->max_state - dfc->capped_state.

Fixes: 615510fe13bd ("thermal: devfreq_cooling: remove old power model and use EM")
Cc: 5.11+ <stable@xxxxxxxxxxxxxxx> # 5.11+
Signed-off-by: Ye Zhang <ye.zhang@xxxxxxxxxxxxxx>
Reviewed-by: Dhruva Gole <d-gole@xxxxxx>
Reviewed-by: Lukasz Luba <lukasz.luba@xxxxxxx>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Signed-off-by: Lukasz Luba <lukasz.luba@xxxxxxx>
---

Hi Greg,

I have solved small backporting conflict to that v5.15.
The patch is based on tag v5.15.99 and it's for this
failing backport:
https://lore.kernel.org/stable/2024033050-imitation-unmixed-ef53@gregkh/

Regards,
Lukasz Luba



 drivers/thermal/devfreq_cooling.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/thermal/devfreq_cooling.c b/drivers/thermal/devfreq_cooling.c
index d38a80adec733..5be79b5d788e5 100644
--- a/drivers/thermal/devfreq_cooling.c
+++ b/drivers/thermal/devfreq_cooling.c
@@ -199,7 +199,7 @@ static int devfreq_cooling_get_requested_power(struct thermal_cooling_device *cd
 
 		res = dfc->power_ops->get_real_power(df, power, freq, voltage);
 		if (!res) {
-			state = dfc->capped_state;
+			state = dfc->max_state - dfc->capped_state;
 			dfc->res_util = dfc->em_pd->table[state].power;
 			dfc->res_util *= SCALE_ERROR_MITIGATION;
 
-- 
2.25.1