Hi, On Fri, Jul 8, 2022 at 11:00 PM Akhil P Oommen <quic_akhilpo@xxxxxxxxxxx> wrote: > > There are some hardware logic under CX domain. For a successful > recovery, we should ensure cx headswitch collapses to ensure all the > stale states are cleard out. This is especially true to for a6xx family > where we can GMU co-processor. > > Currently, cx doesn't collapse due to a devlink between gpu and its > smmu. So the *struct gpu device* needs to be runtime suspended to ensure > that the iommu driver removes its vote on cx gdsc. > > Signed-off-by: Akhil P Oommen <quic_akhilpo@xxxxxxxxxxx> > --- > > (no changes since v1) > > drivers/gpu/drm/msm/adreno/a6xx_gpu.c | 16 ++++++++++++++-- > drivers/gpu/drm/msm/msm_gpu.c | 2 -- > 2 files changed, 14 insertions(+), 4 deletions(-) > > diff --git a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c > index 4d50110..7ed347c 100644 > --- a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c > +++ b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c > @@ -1278,8 +1278,20 @@ static void a6xx_recover(struct msm_gpu *gpu) > */ > gmu_write(&a6xx_gpu->gmu, REG_A6XX_GMU_GMU_PWR_COL_KEEPALIVE, 0); > > - gpu->funcs->pm_suspend(gpu); > - gpu->funcs->pm_resume(gpu); > + /* > + * Now drop all the pm_runtime usage count to allow cx gdsc to collapse. > + * First drop the usage count from all active submits > + */ > + for (i = gpu->active_submits; i > 0; i--) > + pm_runtime_put(&gpu->pdev->dev); > + > + /* And the final one from recover worker */ > + pm_runtime_put_sync(&gpu->pdev->dev); > + > + for (i = gpu->active_submits; i > 0; i--) > + pm_runtime_get(&gpu->pdev->dev); > + > + pm_runtime_get_sync(&gpu->pdev->dev); In response to v1, Rob suggested pm_runtime_force_suspend/resume(). Those seem like they would work to me, too. Why not use them?
