[RFC 7/7] drm/vc4: update cursors asynchronously through atomic

[Robert Foss]

Hey,

I ran the series on a RPi2 and the cursor seems to behave correctly.

Tested-by: Robert Foss <robert.foss at collabora.com>

On 2017-04-09 08:24 PM, Gustavo Padovan wrote:
> From: Gustavo Padovan <gustavo.padovan at collabora.com>
> 
> Add support to async updates of cursors by using the new atomic
> interface for that. Basically what this commit does is do what
> vc4_update_plane() did but through atomic.
> 
> Cc: Eric Anholt <eric at anholt.net>
> Signed-off-by: Gustavo Padovan <gustavo.padovan at collabora.com>
> ---
>   drivers/gpu/drm/vc4/vc4_plane.c | 94 ++++++++++++-----------------------------
>   1 file changed, 27 insertions(+), 67 deletions(-)
> 
> diff --git a/drivers/gpu/drm/vc4/vc4_plane.c b/drivers/gpu/drm/vc4/vc4_plane.c
> index d34cd53..e33c75b 100644
> --- a/drivers/gpu/drm/vc4/vc4_plane.c
> +++ b/drivers/gpu/drm/vc4/vc4_plane.c
> @@ -735,70 +735,27 @@ void vc4_plane_async_set_fb(struct drm_plane *plane, struct drm_framebuffer *fb)
>   	vc4_state->dlist[vc4_state->ptr0_offset] = addr;
>   }
>   
> -static const struct drm_plane_helper_funcs vc4_plane_helper_funcs = {
> -	.atomic_check = vc4_plane_atomic_check,
> -	.atomic_update = vc4_plane_atomic_update,
> -};
> -
> -static void vc4_plane_destroy(struct drm_plane *plane)
> -{
> -	drm_plane_helper_disable(plane);
> -	drm_plane_cleanup(plane);
> -}
> -
> -/* Implements immediate (non-vblank-synced) updates of the cursor
> - * position, or falls back to the atomic helper otherwise.
> - */
> -static int
> -vc4_update_plane(struct drm_plane *plane,
> -		 struct drm_crtc *crtc,
> -		 struct drm_framebuffer *fb,
> -		 int crtc_x, int crtc_y,
> -		 unsigned int crtc_w, unsigned int crtc_h,
> -		 uint32_t src_x, uint32_t src_y,
> -		 uint32_t src_w, uint32_t src_h,
> -		 struct drm_modeset_acquire_ctx *ctx)
> +static int vc4_plane_atomic_async_check(struct drm_plane *plane,
> +					struct drm_plane_state *state)
>   {
> -	struct drm_plane_state *plane_state;
> -	struct vc4_plane_state *vc4_state;
> -
> -	if (plane != crtc->cursor)
> -		goto out;
> -
> -	plane_state = plane->state;
> -	vc4_state = to_vc4_plane_state(plane_state);
> -
> -	if (!plane_state)
> -		goto out;
> +	if (plane != state->crtc->cursor)
> +		return -EINVAL;
>   
> -	/* No configuring new scaling in the fast path. */
> -	if (crtc_w != plane_state->crtc_w ||
> -	    crtc_h != plane_state->crtc_h ||
> -	    src_w != plane_state->src_w ||
> -	    src_h != plane_state->src_h) {
> -		goto out;
> -	}
> +	if (!plane->state)
> +		return -EINVAL;
>   
> -	if (fb != plane_state->fb) {
> -		drm_atomic_set_fb_for_plane(plane->state, fb);
> -		vc4_plane_async_set_fb(plane, fb);
> -	}
> +	return 0;
> +}
>   
> -	/* Set the cursor's position on the screen.  This is the
> -	 * expected change from the drm_mode_cursor_universal()
> -	 * helper.
> -	 */
> -	plane_state->crtc_x = crtc_x;
> -	plane_state->crtc_y = crtc_y;
> +static void vc4_plane_atomic_async_update(struct drm_plane *plane,
> +					  struct drm_plane_state *new_state)
> +{
> +	struct vc4_plane_state *vc4_state = to_vc4_plane_state(plane->state);
>   
> -	/* Allow changing the start position within the cursor BO, if
> -	 * that matters.
> -	 */
> -	plane_state->src_x = src_x;
> -	plane_state->src_y = src_y;
> +	if (plane->state->fb != new_state->fb)
> +		vc4_plane_async_set_fb(plane, new_state->fb);
>   
> -	/* Update the display list based on the new crtc_x/y. */
> -	vc4_plane_atomic_check(plane, plane_state);
> +	plane->state->fb = new_state->fb;
>   
>   	/* Note that we can't just call vc4_plane_write_dlist()
>   	 * because that would smash the context data that the HVS is
> @@ -810,20 +767,23 @@ vc4_update_plane(struct drm_plane *plane,
>   	       &vc4_state->hw_dlist[vc4_state->pos2_offset]);
>   	writel(vc4_state->dlist[vc4_state->ptr0_offset],
>   	       &vc4_state->hw_dlist[vc4_state->ptr0_offset]);
> +}
>   
> -	return 0;
> +static const struct drm_plane_helper_funcs vc4_plane_helper_funcs = {
> +	.atomic_check = vc4_plane_atomic_check,
> +	.atomic_update = vc4_plane_atomic_update,
> +	.atomic_async_check = vc4_plane_atomic_async_check,
> +	.atomic_async_update = vc4_plane_atomic_async_update,
> +};
>   
> -out:
> -	return drm_atomic_helper_update_plane(plane, crtc, fb,
> -					      crtc_x, crtc_y,
> -					      crtc_w, crtc_h,
> -					      src_x, src_y,
> -					      src_w, src_h,
> -					      ctx);
> +static void vc4_plane_destroy(struct drm_plane *plane)
> +{
> +	drm_plane_helper_disable(plane);
> +	drm_plane_cleanup(plane);
>   }
>   
>   static const struct drm_plane_funcs vc4_plane_funcs = {
> -	.update_plane = vc4_update_plane,
> +	.update_plane = drm_atomic_helper_update_plane,
>   	.disable_plane = drm_atomic_helper_disable_plane,
>   	.destroy = vc4_plane_destroy,
>   	.set_property = NULL,
>