drivers/gpu/drm/mediatek/mtk_crtc.c | 34 +++++++++++++++-------------- 1 file changed, 18 insertions(+), 16 deletions(-)
In mtk_crtc_ddp_config(), mtk_crtc will use some configuration flags to
generate instructions to cmdq_handle, such as:
state->pending_config
mtk_crtc->pending_planes
plane_state->pending.config
mtk_crtc->pending_async_planes
plane_state->pending.async_config
These configuration flags may be set to false when a GCE IRQ comes calling
ddp_cmdq_cb(). This may result in missing prepare instructions,
especially if mtk_crtc_update_config() with the flase need_vblank (no need
to wait for vblank) cases.
Therefore, use the mtk_crtc->config_updating flag set at the beginning of
mtk_crtc_update_config() to ensure that these configuration flags won't be
changed when the mtk_crtc_ddp_config() is preparing instructions.
Fixes: 7f82d9c43879 ("drm/mediatek: Clear pending flag when cmdq packet is done")
Signed-off-by: Jason-JH.Lin <jason-jh.lin@mediatek.com>
---
drivers/gpu/drm/mediatek/mtk_crtc.c | 34 +++++++++++++++--------------
1 file changed, 18 insertions(+), 16 deletions(-)
diff --git a/drivers/gpu/drm/mediatek/mtk_crtc.c b/drivers/gpu/drm/mediatek/mtk_crtc.c
index 6f34f573e127..bc3bf0c3edd9 100644
--- a/drivers/gpu/drm/mediatek/mtk_crtc.c
+++ b/drivers/gpu/drm/mediatek/mtk_crtc.c
@@ -314,30 +314,32 @@ static void ddp_cmdq_cb(struct mbox_client *cl, void *mssg)
state = to_mtk_crtc_state(mtk_crtc->base.state);
- state->pending_config = false;
+ if (!mtk_crtc->config_updating) {
+ state->pending_config = false;
- if (mtk_crtc->pending_planes) {
- for (i = 0; i < mtk_crtc->layer_nr; i++) {
- struct drm_plane *plane = &mtk_crtc->planes[i];
- struct mtk_plane_state *plane_state;
+ if (mtk_crtc->pending_planes) {
+ for (i = 0; i < mtk_crtc->layer_nr; i++) {
+ struct drm_plane *plane = &mtk_crtc->planes[i];
+ struct mtk_plane_state *plane_state;
- plane_state = to_mtk_plane_state(plane->state);
+ plane_state = to_mtk_plane_state(plane->state);
- plane_state->pending.config = false;
+ plane_state->pending.config = false;
+ }
+ mtk_crtc->pending_planes = false;
}
- mtk_crtc->pending_planes = false;
- }
- if (mtk_crtc->pending_async_planes) {
- for (i = 0; i < mtk_crtc->layer_nr; i++) {
- struct drm_plane *plane = &mtk_crtc->planes[i];
- struct mtk_plane_state *plane_state;
+ if (mtk_crtc->pending_async_planes) {
+ for (i = 0; i < mtk_crtc->layer_nr; i++) {
+ struct drm_plane *plane = &mtk_crtc->planes[i];
+ struct mtk_plane_state *plane_state;
- plane_state = to_mtk_plane_state(plane->state);
+ plane_state = to_mtk_plane_state(plane->state);
- plane_state->pending.async_config = false;
+ plane_state->pending.async_config = false;
+ }
+ mtk_crtc->pending_async_planes = false;
}
- mtk_crtc->pending_async_planes = false;
}
mtk_crtc->cmdq_vblank_cnt = 0;
--
2.18.0Hi, Jason:
Jason-JH.Lin <jason-jh.lin@mediatek.com> 於 2024年7月3日 週三 下午6:33寫道：
>
> In mtk_crtc_ddp_config(), mtk_crtc will use some configuration flags to
> generate instructions to cmdq_handle, such as:
> state->pending_config
> mtk_crtc->pending_planes
> plane_state->pending.config
> mtk_crtc->pending_async_planes
> plane_state->pending.async_config
>
> These configuration flags may be set to false when a GCE IRQ comes calling
> ddp_cmdq_cb(). This may result in missing prepare instructions,
> especially if mtk_crtc_update_config() with the flase need_vblank (no need
> to wait for vblank) cases.
>
> Therefore, use the mtk_crtc->config_updating flag set at the beginning of
> mtk_crtc_update_config() to ensure that these configuration flags won't be
> changed when the mtk_crtc_ddp_config() is preparing instructions.
>
> Fixes: 7f82d9c43879 ("drm/mediatek: Clear pending flag when cmdq packet is done")
> Signed-off-by: Jason-JH.Lin <jason-jh.lin@mediatek.com>
> ---
> drivers/gpu/drm/mediatek/mtk_crtc.c | 34 +++++++++++++++--------------
> 1 file changed, 18 insertions(+), 16 deletions(-)
>
> diff --git a/drivers/gpu/drm/mediatek/mtk_crtc.c b/drivers/gpu/drm/mediatek/mtk_crtc.c
> index 6f34f573e127..bc3bf0c3edd9 100644
> --- a/drivers/gpu/drm/mediatek/mtk_crtc.c
> +++ b/drivers/gpu/drm/mediatek/mtk_crtc.c
> @@ -314,30 +314,32 @@ static void ddp_cmdq_cb(struct mbox_client *cl, void *mssg)
>
> state = to_mtk_crtc_state(mtk_crtc->base.state);
>
> - state->pending_config = false;
> + if (!mtk_crtc->config_updating) {
> + state->pending_config = false;
I think if mtk_crtc->config_updating == true, the whole clear job
could be skipped.
And use spin_lock to protect the clear job in irq.
/*
spin_lock():
if (mtk_crtc->config_updating) {
spin_unlock();
goto out;
}
/* clear job */
spin_unlock();
*/
out:
In mtk_crtc_config_update(), use spin_lock to protect mtk_crtc->config_updating:
spin_lock();
mtk_crtc->config_updating = true;
spin_unlock();
...
spin_lock();
mtk_crtc->config_updating = false;
spin_unlock();
Regards,
Chun-Kuang.
>
> - if (mtk_crtc->pending_planes) {
> - for (i = 0; i < mtk_crtc->layer_nr; i++) {
> - struct drm_plane *plane = &mtk_crtc->planes[i];
> - struct mtk_plane_state *plane_state;
> + if (mtk_crtc->pending_planes) {
> + for (i = 0; i < mtk_crtc->layer_nr; i++) {
> + struct drm_plane *plane = &mtk_crtc->planes[i];
> + struct mtk_plane_state *plane_state;
>
> - plane_state = to_mtk_plane_state(plane->state);
> + plane_state = to_mtk_plane_state(plane->state);
>
> - plane_state->pending.config = false;
> + plane_state->pending.config = false;
> + }
> + mtk_crtc->pending_planes = false;
> }
> - mtk_crtc->pending_planes = false;
> - }
>
> - if (mtk_crtc->pending_async_planes) {
> - for (i = 0; i < mtk_crtc->layer_nr; i++) {
> - struct drm_plane *plane = &mtk_crtc->planes[i];
> - struct mtk_plane_state *plane_state;
> + if (mtk_crtc->pending_async_planes) {
> + for (i = 0; i < mtk_crtc->layer_nr; i++) {
> + struct drm_plane *plane = &mtk_crtc->planes[i];
> + struct mtk_plane_state *plane_state;
>
> - plane_state = to_mtk_plane_state(plane->state);
> + plane_state = to_mtk_plane_state(plane->state);
>
> - plane_state->pending.async_config = false;
> + plane_state->pending.async_config = false;
> + }
> + mtk_crtc->pending_async_planes = false;
> }
> - mtk_crtc->pending_async_planes = false;
> }
>
> mtk_crtc->cmdq_vblank_cnt = 0;
> --
> 2.18.0
>
Hi CK,
> > --- a/drivers/gpu/drm/mediatek/mtk_crtc.c
> > +++ b/drivers/gpu/drm/mediatek/mtk_crtc.c
> > @@ -314,30 +314,32 @@ static void ddp_cmdq_cb(struct mbox_client
> *cl, void *mssg)
> >
> > state = to_mtk_crtc_state(mtk_crtc->base.state);
> >
> > - state->pending_config = false;
> > + if (!mtk_crtc->config_updating) {
> > + state->pending_config = false;
>
> I think if mtk_crtc->config_updating == true, the whole clear job
> could be skipped.
> And use spin_lock to protect the clear job in irq.
>
> /*
> spin_lock():
> if (mtk_crtc->config_updating) {
> spin_unlock();
> goto out;
> }
>
> /* clear job */
>
> spin_unlock();
> */
> out:
>
> In mtk_crtc_config_update(), use spin_lock to protect mtk_crtc-
> >config_updating:
>
> spin_lock();
> mtk_crtc->config_updating = true;
> spin_unlock();
> ...
> spin_lock();
> mtk_crtc->config_updating = false;
> spin_unlock();
>
Thanks for the reviews.
I think that's more solid to protect the updating config of cmd buffer.
I will also add spin_lock for the whole statement in
mtk_drm_finish_page_flip() because config_updating flag is covered the
pending_need_vblank flag.
Regards,
Jason-JH.Lin
> Regards,
> Chun-Kuang.
>
>
> >
> > - if (mtk_crtc->pending_planes) {
> > - for (i = 0; i < mtk_crtc->layer_nr; i++) {
> > - struct drm_plane *plane = &mtk_crtc-
> >planes[i];
> > - struct mtk_plane_state *plane_state;
> > + if (mtk_crtc->pending_planes) {
> > + for (i = 0; i < mtk_crtc->layer_nr; i++) {
> > + struct drm_plane *plane =
> &mtk_crtc->planes[i];
> > + struct mtk_plane_state
> *plane_state;
> >
> > - plane_state = to_mtk_plane_state(plane-
> >state);
> > + plane_state =
> to_mtk_plane_state(plane->state);
> >
> > - plane_state->pending.config = false;
> > + plane_state->pending.config =
> false;
> > + }
> > + mtk_crtc->pending_planes = false;
> > }
> > - mtk_crtc->pending_planes = false;
> > - }
> >
> > - if (mtk_crtc->pending_async_planes) {
> > - for (i = 0; i < mtk_crtc->layer_nr; i++) {
> > - struct drm_plane *plane = &mtk_crtc-
> >planes[i];
> > - struct mtk_plane_state *plane_state;
> > + if (mtk_crtc->pending_async_planes) {
> > + for (i = 0; i < mtk_crtc->layer_nr; i++) {
> > + struct drm_plane *plane =
> &mtk_crtc->planes[i];
> > + struct mtk_plane_state
> *plane_state;
> >
> > - plane_state = to_mtk_plane_state(plane-
> >state);
> > + plane_state =
> to_mtk_plane_state(plane->state);
> >
> > - plane_state->pending.async_config = false;
> > + plane_state->pending.async_config =
> false;
> > + }
> > + mtk_crtc->pending_async_planes = false;
> > }
> > - mtk_crtc->pending_async_planes = false;
> > }
> >
> > mtk_crtc->cmdq_vblank_cnt = 0;
> > --
> > 2.18.0
> >
Il 03/07/24 12:33, Jason-JH.Lin ha scritto:
> In mtk_crtc_ddp_config(), mtk_crtc will use some configuration flags to
> generate instructions to cmdq_handle, such as:
> state->pending_config
> mtk_crtc->pending_planes
> plane_state->pending.config
> mtk_crtc->pending_async_planes
> plane_state->pending.async_config
>
> These configuration flags may be set to false when a GCE IRQ comes calling
> ddp_cmdq_cb(). This may result in missing prepare instructions,
> especially if mtk_crtc_update_config() with the flase need_vblank (no need
> to wait for vblank) cases.
>
> Therefore, use the mtk_crtc->config_updating flag set at the beginning of
> mtk_crtc_update_config() to ensure that these configuration flags won't be
> changed when the mtk_crtc_ddp_config() is preparing instructions.
>
> Fixes: 7f82d9c43879 ("drm/mediatek: Clear pending flag when cmdq packet is done")
> Signed-off-by: Jason-JH.Lin <jason-jh.lin@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
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