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

From: Yongqiang Niu
Date: Tue Dec 03 2019 - 02:43:57 EST


On Tue, 2019-12-03 at 13:48 +0800, CK Hu wrote:
> Hi, Yongqiang:
>
> On Wed, 2019-11-27 at 09:17 +0800, yongqiang.niu@xxxxxxxxxxxx wrote:
> > From: Yongqiang Niu <yongqiang.niu@xxxxxxxxxxxx>
> >
> > Problem:
> > overlay hangup when external display hotplut test
> >
> > Fix:
> > disable overlay when crtc disable
>
> I think you do two things in this patch. The first is to config layer
> before component start, and the second is disable layer when crtc
> disable. So separate to two patches.
>
> >
> > Signed-off-by: Yongqiang Niu <yongqiang.niu@xxxxxxxxxxxx>
> > ---
> > drivers/gpu/drm/mediatek/mtk_drm_crtc.c | 39 +++++++++++++++++++++------------
> > 1 file changed, 25 insertions(+), 14 deletions(-)
> >
> > 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);
>
> I'm confused with this part. The design of this loop is to set
> plane_state->pending.enable = false and wait for irq handler to write
> register. Why do you directly write register?
>
> Regards,
> CK

when cmdq enable, mtk_crtc->cmdq_client will be always true when crtc
create, there is no chance for mtk_crtc_ddp_config process in ddp irq
callback function
>
> > }
> > mtk_crtc->pending_planes = true;
> >
>
>