From: Rob Clark robdclark@chromium.org
Because system suspend uses pm_runtime_force_suspend() we can't rely runpm refcnt's to protect us if the GPU is active, etc. Fortunately *usually* the GPU is idle when system suspend is triggered. But that isn't quite good enough.
The first patch attempts to block for a modest amount of time until GPU is idle (and failing that, returns -EBUSY). We could have taken a slightly easier approach and just returned -EBUSY if GPU is not idle, but that would cause system suspend to fail. And no one likes pulling a hot laptop out of their backpack.
The second patch avoids getting devfreq callbacks after suspend, since pm_runtime_force_suspend() breaks the pm_runtime_get_if_in_use() tricks used to deal with devfreq callbacks while suspended.
Rob Clark (2): drm/msm/gpu: Wait for idle before suspending drm/msm/gpu: Cancel idle/boost work on suspend
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 +++ drivers/gpu/drm/msm/msm_gpu_devfreq.c | 21 +++++++++++++++++++-- 4 files changed, 43 insertions(+), 2 deletions(-)
From: Rob Clark robdclark@chromium.org
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.
Signed-off-by: Rob Clark robdclark@chromium.org Reviewed-by: Bjorn Andersson bjorn.andersson@linaro.org Reviewed-by: AngeloGioacchino Del Regno angelogioacchino.delregno@collabora.com --- 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 93005839b5da..a502ffafb739 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 0f78c2615272..2c1049c0ea14 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 445c6bfd4b6b..92aa1e9196c6 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;
From: Rob Clark robdclark@chromium.org
With system suspend using pm_runtime_force_suspend() we can't rely on the pm_runtime_get_if_in_use() trick to deal with devfreq callbacks after (or racing with) suspend. So flush any pending idle or boost work in the suspend path.
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)
Signed-off-by: Rob Clark robdclark@chromium.org --- drivers/gpu/drm/msm/msm_gpu_devfreq.c | 21 +++++++++++++++++++-- 1 file changed, 19 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/msm/msm_gpu_devfreq.c b/drivers/gpu/drm/msm/msm_gpu_devfreq.c index 62405e980925..9bf319be11f6 100644 --- a/drivers/gpu/drm/msm/msm_gpu_devfreq.c +++ b/drivers/gpu/drm/msm/msm_gpu_devfreq.c @@ -133,6 +133,18 @@ void msm_devfreq_init(struct msm_gpu *gpu) CLOCK_MONOTONIC, HRTIMER_MODE_REL); }
+static void cancel_idle_work(struct msm_gpu_devfreq *df) +{ + hrtimer_cancel(&df->idle_work.timer); + kthread_cancel_work_sync(&df->idle_work.work); +} + +static void cancel_boost_work(struct msm_gpu_devfreq *df) +{ + hrtimer_cancel(&df->boost_work.timer); + kthread_cancel_work_sync(&df->boost_work.work); +} + void msm_devfreq_cleanup(struct msm_gpu *gpu) { struct msm_gpu_devfreq *df = &gpu->devfreq; @@ -152,7 +164,12 @@ void msm_devfreq_resume(struct msm_gpu *gpu)
void msm_devfreq_suspend(struct msm_gpu *gpu) { - devfreq_suspend_device(gpu->devfreq.devfreq); + struct msm_gpu_devfreq *df = &gpu->devfreq; + + devfreq_suspend_device(df->devfreq); + + cancel_idle_work(df); + cancel_boost_work(df); }
static void msm_devfreq_boost_work(struct kthread_work *work) @@ -196,7 +213,7 @@ void msm_devfreq_active(struct msm_gpu *gpu) /* * Cancel any pending transition to idle frequency: */ - hrtimer_cancel(&df->idle_work.timer); + cancel_idle_work(df);
idle_time = ktime_to_ms(ktime_sub(ktime_get(), df->idle_time));
dri-devel@lists.freedesktop.org
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Rob Clark