Re: [PATCH] drm/amdgpu: switch DM to atomic fence helpers v2

["Christian König" <christian.koenig@amd.com>]

Harry, Nicholas once more a gentle ping on this.

Any objections/comments? Otherwise I'm going to push this through 
drm-misc-next.

Thanks,
Christian.

Am 09.05.22 um 09:47 schrieb Christian König:
> This gives us the standard atomic implicit and explicit fencing rules.
>
> v2: move the wait to amdgpu_dm_atomic_commit_tail
>
> Signed-off-by: Christian König <christian.koenig@amd.com>
> Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
> Cc: Harry Wentland <harry.wentland@amd.com>
> Cc: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
> Cc: Roman Li <Roman.Li@amd.com>
> Cc: Qingqing Zhuo <qingqing.zhuo@amd.com>
> Cc: Jude Shih <shenshih@amd.com>
> Cc: Wayne Lin <Wayne.Lin@amd.com>
> Cc: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
> ---
>   .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 23 ++++++++-----------
>   1 file changed, 10 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> index a6880dd9c0bb..f9ce8cb45e6d 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> @@ -83,6 +83,7 @@
>   #include <drm/drm_edid.h>
>   #include <drm/drm_vblank.h>
>   #include <drm/drm_audio_component.h>
> +#include <drm/drm_gem_atomic_helper.h>
>   
>   #if defined(CONFIG_DRM_AMD_DC_DCN)
>   #include "ivsrcid/dcn/irqsrcs_dcn_1_0.h"
> @@ -7627,6 +7628,10 @@ static int dm_plane_helper_prepare_fb(struct drm_plane *plane,
>   		goto error_unpin;
>   	}
>   
> +	r = drm_gem_plane_helper_prepare_fb(plane, new_state);
> +	if (unlikely(r != 0))
> +		goto error_unpin;
> +
>   	amdgpu_bo_unreserve(rbo);
>   
>   	afb->address = amdgpu_bo_gpu_offset(rbo);
> @@ -9160,7 +9165,6 @@ static void amdgpu_dm_commit_planes(struct drm_atomic_state *state,
>   	struct dm_crtc_state *dm_old_crtc_state =
>   			to_dm_crtc_state(drm_atomic_get_old_crtc_state(state, pcrtc));
>   	int planes_count = 0, vpos, hpos;
> -	long r;
>   	unsigned long flags;
>   	struct amdgpu_bo *abo;
>   	uint32_t target_vblank, last_flip_vblank;
> @@ -9235,18 +9239,6 @@ static void amdgpu_dm_commit_planes(struct drm_atomic_state *state,
>   		}
>   
>   		abo = gem_to_amdgpu_bo(fb->obj[0]);
> -
> -		/*
> -		 * Wait for all fences on this FB. Do limited wait to avoid
> -		 * deadlock during GPU reset when this fence will not signal
> -		 * but we hold reservation lock for the BO.
> -		 */
> -		r = dma_resv_wait_timeout(abo->tbo.base.resv,
> -					  DMA_RESV_USAGE_WRITE, false,
> -					  msecs_to_jiffies(5000));
> -		if (unlikely(r <= 0))
> -			DRM_ERROR("Waiting for fences timed out!");
> -
>   		fill_dc_plane_info_and_addr(
>   			dm->adev, new_plane_state,
>   			afb->tiling_flags,
> @@ -9591,9 +9583,14 @@ static void amdgpu_dm_atomic_commit_tail(struct drm_atomic_state *state)
>   	struct dm_crtc_state *dm_old_crtc_state, *dm_new_crtc_state;
>   	int crtc_disable_count = 0;
>   	bool mode_set_reset_required = false;
> +	int r;
>   
>   	trace_amdgpu_dm_atomic_commit_tail_begin(state);
>   
> +	r = drm_atomic_helper_wait_for_fences(dev, state, false);
> +	if (unlikely(r))
> +		DRM_ERROR("Waiting for fences timed out!");
> +
>   	drm_atomic_helper_update_legacy_modeset_state(dev, state);
>   
>   	dm_state = dm_atomic_get_new_state(state);