[PATCH 2/2] drm/sti: do not post HQVDP command if no update

[Benjamin Gaignard]

Acked-by: Benjamin Gaignard <benjamin.gaignard at linaro.org>

2016-12-05 16:09 GMT+01:00 Fabien Dessenne <fabien.dessenne at st.com>:
> Do not process update requests with unmodified parameters.
>
> Since the HQVDP command queue is limited to 2, we shall take care of
> not posting unneeded commands, which would abusively fill the command
> queue leading to frame update skip.
> This typically happens when the driver is called with legacy
> (non-atomic) IOCTL : in that case atomic_update() is called multiple
> times with the same parameters.
>
> Signed-off-by: Fabien Dessenne <fabien.dessenne at st.com>
> ---
>  drivers/gpu/drm/sti/sti_hqvdp.c | 15 +++++++++++++++
>  1 file changed, 15 insertions(+)
>
> diff --git a/drivers/gpu/drm/sti/sti_hqvdp.c b/drivers/gpu/drm/sti/sti_hqvdp.c
> index a547723..55cbaea 100644
> --- a/drivers/gpu/drm/sti/sti_hqvdp.c
> +++ b/drivers/gpu/drm/sti/sti_hqvdp.c
> @@ -1117,6 +1117,21 @@ static void sti_hqvdp_atomic_update(struct drm_plane *drm_plane,
>         if (!crtc || !fb)
>                 return;
>
> +       if ((oldstate->fb == state->fb) &&
> +           (oldstate->crtc_x == state->crtc_x) &&
> +           (oldstate->crtc_y == state->crtc_y) &&
> +           (oldstate->crtc_w == state->crtc_w) &&
> +           (oldstate->crtc_h == state->crtc_h) &&
> +           (oldstate->src_x == state->src_x) &&
> +           (oldstate->src_y == state->src_y) &&
> +           (oldstate->src_w == state->src_w) &&
> +           (oldstate->src_h == state->src_h)) {
> +               /* No change since last update, do not post cmd */
> +               DRM_DEBUG_DRIVER("No change, not posting cmd\n");
> +               plane->status = STI_PLANE_UPDATED;
> +               return;
> +       }
> +
>         mode = &crtc->mode;
>         dst_x = state->crtc_x;
>         dst_y = state->crtc_y;
> --
> 2.7.4
>



-- 
Benjamin Gaignard

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