[PATCH 4/8] drm/msm/devfreq: Record idle_time at GPU idle onset

[Akhil P Oommen <akhilpo@oss.qualcomm.com>]

From: Jie Zhang <jie.zhang@oss.qualcomm.com>

Setting df->idle_time in msm_devfreq_idle_work() means a cancelled
idle_work leaves a stale timestamp, causing idle_time to accumulate
across idle cycles and potentially trigger a spurious devfreq boost.

Move the assignment to msm_devfreq_idle() so the timestamp always
reflects the actual GPU idle onset.

Fixes: 658f4c829688 ("drm/msm/devfreq: Add 1ms delay before clamping freq")
Cc: stable@vger.kernel.org
Signed-off-by: Jie Zhang <jie.zhang@oss.qualcomm.com>
Signed-off-by: Akhil P Oommen <akhilpo@oss.qualcomm.com>
---
 drivers/gpu/drm/msm/msm_gpu_devfreq.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/msm/msm_gpu_devfreq.c b/drivers/gpu/drm/msm/msm_gpu_devfreq.c
index 2e1d5c343272..f3c664b20a1b 100644
--- a/drivers/gpu/drm/msm/msm_gpu_devfreq.c
+++ b/drivers/gpu/drm/msm/msm_gpu_devfreq.c
@@ -357,7 +357,6 @@ static void msm_devfreq_idle_work(struct kthread_work *work)
 	if (priv->gpu_clamp_to_idle)
 		msm_devfreq_target(&gpu->pdev->dev, &target_freq, 0);
 
-	df->idle_time = ktime_get();
 	df->idle_freq = idle_freq;
 
 	mutex_unlock(&df->devfreq->lock);
@@ -370,6 +369,8 @@ void msm_devfreq_idle(struct msm_gpu *gpu)
 	if (!has_devfreq(gpu))
 		return;
 
+	df->idle_time = ktime_get();
+
 	msm_hrtimer_queue_work(&df->idle_work, ms_to_ktime(1),
 			       HRTIMER_MODE_REL);
 }

-- 
2.55.0