Re: [v1,1/2] drm/mediatek: Fixup external display black screen issue

[Hsin-Yi Wang]

On Wed, Nov 27, 2019 at 1:17 AM <yongqiang.niu@xxxxxxxxxxxx> wrote:
>
> From: Yongqiang Niu <yongqiang.niu@xxxxxxxxxxxx>
>
> Problem:
> overlay hangup when external display hotplut test
>
> Fix:
> disable overlay when crtc disable
>
> Signed-off-by: Yongqiang Niu <yongqiang.niu@xxxxxxxxxxxx>
> ---
>  drivers/gpu/drm/mediatek/mtk_drm_crtc.c | 39 +++++++++++++++++++++------------
>  1 file changed, 25 insertions(+), 14 deletions(-)
>
> --
> 1.8.1.1.dirty
>
> diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> index 4fb346c..7eca02f 100644
> --- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> +++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> @@ -369,6 +369,20 @@ static int mtk_crtc_ddp_hw_init(struct mtk_drm_crtc *mtk_crtc)
>         mtk_disp_mutex_add_comp(mtk_crtc->mutex, mtk_crtc->ddp_comp[i]->id);
>         mtk_disp_mutex_enable(mtk_crtc->mutex);
>
> +       /* Initially configure all planes */
> +       for (i = 0; i < mtk_crtc->layer_nr; i++) {
> +               struct drm_plane *plane = &mtk_crtc->planes[i];
> +               struct mtk_plane_state *plane_state;
> +               struct mtk_ddp_comp *comp;
> +               unsigned int local_layer;
> +
> +               plane_state = to_mtk_plane_state(plane->state);
> +               comp = mtk_drm_ddp_comp_for_plane(crtc, plane, &local_layer);
> +               if (comp)
> +                       mtk_ddp_comp_layer_config(comp, local_layer,
> +                                                 plane_state, NULL);
> +       }
> +
>         for (i = 0; i < mtk_crtc->ddp_comp_nr; i++) {
>                 struct mtk_ddp_comp *comp = mtk_crtc->ddp_comp[i];
>                 enum mtk_ddp_comp_id prev;
> @@ -385,20 +399,6 @@ static int mtk_crtc_ddp_hw_init(struct mtk_drm_crtc *mtk_crtc)
>                 mtk_ddp_comp_start(comp);
>         }
>
> -       /* Initially configure all planes */
> -       for (i = 0; i < mtk_crtc->layer_nr; i++) {
> -               struct drm_plane *plane = &mtk_crtc->planes[i];
> -               struct mtk_plane_state *plane_state;
> -               struct mtk_ddp_comp *comp;
> -               unsigned int local_layer;
> -
> -               plane_state = to_mtk_plane_state(plane->state);
> -               comp = mtk_drm_ddp_comp_for_plane(crtc, plane, &local_layer);
> -               if (comp)
> -                       mtk_ddp_comp_layer_config(comp, local_layer,
> -                                                 plane_state, NULL);
> -       }
> -
>         return 0;
>
>  err_mutex_unprepare:
> @@ -607,10 +607,21 @@ static void mtk_drm_crtc_atomic_disable(struct drm_crtc *crtc,
>         for (i = 0; i < mtk_crtc->layer_nr; i++) {
>                 struct drm_plane *plane = &mtk_crtc->planes[i];
>                 struct mtk_plane_state *plane_state;
> +               struct mtk_ddp_comp *comp = mtk_crtc->ddp_comp[0];
> +               unsigned int comp_layer_nr = mtk_ddp_comp_layer_nr(comp);
> +               unsigned int local_layer;
>
>                 plane_state = to_mtk_plane_state(plane->state);
>                 plane_state->pending.enable = false;
>                 plane_state->pending.config = true;
> +
> +               if (i >= comp_layer_nr) {
> +                       comp = mtk_crtc->ddp_comp[1];
> +                       local_layer = i - comp_layer_nr;
> +               } else
> +                       local_layer = i;
> +               mtk_ddp_comp_layer_config(comp, local_layer,
> +                                         plane_state, NULL);
This part should be moved to mtk_crtc_ddp_hw_fini(), or at least
called after drm_crtc_vblank_off(). Otherwise we would see
drm_wait_one_vblank warnings on 8173 when display turns off.

[   25.696182] Call trace:
[   25.698624]  drm_wait_one_vblank+0x1f0/0x1fc
[   25.702886]  drm_crtc_wait_one_vblank+0x20/0x2c
[   25.707415]  mtk_drm_crtc_atomic_disable+0xf0/0x308
[   25.712287]  drm_atomic_helper_commit_modeset_disables+0x1b8/0x3c0
[   25.718461]  mtk_atomic_complete+0x88/0x16c
[   25.722638]  mtk_atomic_commit+0xa8/0xb0
[   25.726553]  drm_atomic_commit+0x50/0x5c
[   25.730469]  drm_atomic_helper_set_config+0x98/0xa0
[   25.735341]  drm_mode_setcrtc+0x280/0x608
[   25.739344]  drm_ioctl_kernel+0xcc/0x10c
[   25.743261]  drm_ioctl+0x240/0x3c0
[   25.746658]  drm_compat_ioctl+0xd8/0xe8
[   25.750487]  __se_compat_sys_ioctl+0x100/0x26fc
[   25.755009]  __arm64_compat_sys_ioctl+0x20/0x2c
[   25.759534]  el0_svc_common+0xa4/0x154
[   25.763277]  el0_svc_compat_handler+0x2c/0x38
[   25.767628]  el0_svc_compat+0x8/0x18
[   25.771195] ---[ end trace f4619fdac8f1c0ff ]---

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