From 167a668ab0edf92bfd043bafd24e7f895d074173 Mon Sep 17 00:00:00 2001 From: Rob Clark Date: Sat, 8 Jan 2022 10:09:10 -0800 Subject: [PATCH] drm/msm/gpu: Wait for idle before suspending System suspend uses pm_runtime_force_suspend(), which cheekily bypasses the runpm reference counts. This doesn't actually work so well when the GPU is active. So add a reasonable delay waiting for the GPU to become idle. Alternatively we could just return -EBUSY in this case, but that has the disadvantage of causing system suspend to fail. v2: s/ret/remaining [sboyd], and switch to using active_submits count to ensure we aren't racing with submit cleanup (and devfreq idle work getting scheduled, etc) v3: fix inverted logic Signed-off-by: Rob Clark Reviewed-by: Bjorn Andersson Reviewed-by: AngeloGioacchino Del Regno Link: https://lore.kernel.org/r/20220108180913.814448-2-robdclark@gmail.com Signed-off-by: Rob Clark --- drivers/gpu/drm/msm/adreno/adreno_device.c | 18 ++++++++++++++++++ drivers/gpu/drm/msm/msm_gpu.c | 3 +++ drivers/gpu/drm/msm/msm_gpu.h | 3 +++ 3 files changed, 24 insertions(+) diff --git a/drivers/gpu/drm/msm/adreno/adreno_device.c b/drivers/gpu/drm/msm/adreno/adreno_device.c index 9300583..fb26193 100644 --- a/drivers/gpu/drm/msm/adreno/adreno_device.c +++ b/drivers/gpu/drm/msm/adreno/adreno_device.c @@ -608,9 +608,27 @@ static int adreno_resume(struct device *dev) return gpu->funcs->pm_resume(gpu); } +static int active_submits(struct msm_gpu *gpu) +{ + int active_submits; + mutex_lock(&gpu->active_lock); + active_submits = gpu->active_submits; + mutex_unlock(&gpu->active_lock); + return active_submits; +} + static int adreno_suspend(struct device *dev) { struct msm_gpu *gpu = dev_to_gpu(dev); + int remaining; + + remaining = wait_event_timeout(gpu->retire_event, + active_submits(gpu) == 0, + msecs_to_jiffies(1000)); + if (remaining == 0) { + dev_err(dev, "Timeout waiting for GPU to suspend\n"); + return -EBUSY; + } return gpu->funcs->pm_suspend(gpu); } diff --git a/drivers/gpu/drm/msm/msm_gpu.c b/drivers/gpu/drm/msm/msm_gpu.c index 0f78c26..2c1049c 100644 --- a/drivers/gpu/drm/msm/msm_gpu.c +++ b/drivers/gpu/drm/msm/msm_gpu.c @@ -703,6 +703,8 @@ static void retire_submits(struct msm_gpu *gpu) } } } + + wake_up_all(&gpu->retire_event); } static void retire_worker(struct kthread_work *work) @@ -848,6 +850,7 @@ int msm_gpu_init(struct drm_device *drm, struct platform_device *pdev, INIT_LIST_HEAD(&gpu->active_list); mutex_init(&gpu->active_lock); mutex_init(&gpu->lock); + init_waitqueue_head(&gpu->retire_event); kthread_init_work(&gpu->retire_work, retire_worker); kthread_init_work(&gpu->recover_work, recover_worker); kthread_init_work(&gpu->fault_work, fault_worker); diff --git a/drivers/gpu/drm/msm/msm_gpu.h b/drivers/gpu/drm/msm/msm_gpu.h index 445c6bf..92aa1e9 100644 --- a/drivers/gpu/drm/msm/msm_gpu.h +++ b/drivers/gpu/drm/msm/msm_gpu.h @@ -230,6 +230,9 @@ struct msm_gpu { /* work for handling GPU recovery: */ struct kthread_work recover_work; + /** retire_event: notified when submits are retired: */ + wait_queue_head_t retire_event; + /* work for handling active-list retiring: */ struct kthread_work retire_work; -- 2.7.4