[PATCH 4/5] drm/repaper: Implement {begin,end}_fb_access helpers

[Noralf Trønnes]

Den 17.10.2022 13.15, skrev Thomas Zimmermann:
> Call drm_gem_fb_begin_cpu_access() and drm_gem_fb_end_cpu_access() in
> the simple pipe's {begin,end}_fb_access helpers. This allows to abort
> commits correctly after observing an error.
> 
> Remove the corresponding CPU-access calls from the driver's damage
> handler. It runs during the atomic-apply phase when it's already too
> late to handle errors.
> 
> Signed-off-by: Thomas Zimmermann <tzimmermann at suse.de>
> ---
>  drivers/gpu/drm/tiny/repaper.c | 30 ++++++++++++++++++++++++------
>  1 file changed, 24 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/gpu/drm/tiny/repaper.c b/drivers/gpu/drm/tiny/repaper.c
> index e62f4d16b2c6b..e0f1ac8ab2186 100644
> --- a/drivers/gpu/drm/tiny/repaper.c
> +++ b/drivers/gpu/drm/tiny/repaper.c
> @@ -539,10 +539,6 @@ static int repaper_fb_dirty(struct drm_framebuffer *fb)
>  		goto out_exit;
>  	}
>  
> -	ret = drm_gem_fb_begin_cpu_access(fb, DMA_FROM_DEVICE);
> -	if (ret)
> -		goto out_free;
> -
>  	iosys_map_set_vaddr(&dst, buf);
>  	iosys_map_set_vaddr(&vmap, dma_obj->vaddr);
>  	drm_fb_xrgb8888_to_mono(&dst, &dst_pitch, &vmap, fb, &clip);

You forgot to remove the drm_gem_fb_end_cpu_access() call here.

> @@ -596,8 +592,6 @@ static int repaper_fb_dirty(struct drm_framebuffer *fb)
>  			}
>  	}
>  
> -out_free:
> -	kfree(buf);

The kfree() needs to stay.

With that fixed:

Acked-by: Noralf Trønnes <noralf at tronnes.org>

>  out_exit:
>  	drm_dev_exit(idx);
>  
> @@ -839,11 +833,35 @@ static void repaper_pipe_update(struct drm_simple_display_pipe *pipe,
>  		repaper_fb_dirty(state->fb);
>  }
>  
> +static int repaper_pipe_begin_fb_access(struct drm_simple_display_pipe *pipe,
> +					struct drm_plane_state *plane_state)
> +{
> +	struct drm_framebuffer *fb = plane_state->fb;
> +
> +	if (!fb)
> +		return 0;
> +
> +	return drm_gem_fb_begin_cpu_access(fb, DMA_FROM_DEVICE);
> +}
> +
> +static void repaper_pipe_end_fb_access(struct drm_simple_display_pipe *pipe,
> +				       struct drm_plane_state *plane_state)
> +{
> +	struct drm_framebuffer *fb = plane_state->fb;
> +
> +	if (!fb)
> +		return;
> +
> +	drm_gem_fb_end_cpu_access(fb, DMA_FROM_DEVICE);
> +}
> +
>  static const struct drm_simple_display_pipe_funcs repaper_pipe_funcs = {
>  	.mode_valid = repaper_pipe_mode_valid,
>  	.enable = repaper_pipe_enable,
>  	.disable = repaper_pipe_disable,
>  	.update = repaper_pipe_update,
> +	.begin_fb_access = repaper_pipe_begin_fb_access,
> +	.end_fb_access = repaper_pipe_end_fb_access,
>  };
>  
>  static int repaper_connector_get_modes(struct drm_connector *connector)