Re: [PATCH v2 3/6] drm/mediatek: update cursors by using async atomic update

Hi, Bibby:

You move the mutex protection to [PATCH v2 6/6] drm/mediatek: apply CMDQ control flow, but the race condition exist in this patch. So you should move that back in this patch.

Regards, CK

On Tue, 2019-12-03 at 15:10 +0800, Bibby Hsieh wrote:

Support to async updates of cursors by using the new atomic interface for that.

Signed-off-by: Bibby Hsieh bibby.hsieh@mediatek.com

drivers/gpu/drm/mediatek/mtk_drm_crtc.c | 33 ++++++++++++++++ drivers/gpu/drm/mediatek/mtk_drm_crtc.h | 2 + drivers/gpu/drm/mediatek/mtk_drm_plane.c | 50 ++++++++++++++++++++++++ drivers/gpu/drm/mediatek/mtk_drm_plane.h | 2 + 4 files changed, 87 insertions(+)

diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c index 4c25ad2182b0..b23fe74b8b0a 100644 --- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c +++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c @@ -422,6 +422,39 @@ int mtk_drm_crtc_plane_check(struct drm_crtc *crtc, struct drm_plane *plane, return 0; }

+void mtk_drm_crtc_async_update(struct drm_crtc *crtc, struct drm_plane *plane,

• 	       struct drm_plane_state *new_state)
  

+{

• struct mtk_drm_private *priv = crtc->dev->dev_private;
• struct mtk_drm_crtc *mtk_crtc = to_mtk_crtc(crtc);
• const struct drm_plane_helper_funcs *plane_helper_funcs =

• 	plane->helper_private;
  

• int i;
• if (!mtk_crtc->enabled)

• return;
  

• plane_helper_funcs->atomic_update(plane, new_state);
• 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);
  

• if (plane_state->pending.async_dirty) {
  

• 	plane_state->pending.config = true;
  

• 	plane_state->pending.async_update = false;
  

• 	plane_state->pending.async_dirty = false;
  

• }
  

• }
• mtk_crtc->pending_planes = true;
• if (priv->data->shadow_register) {

• mtk_disp_mutex_acquire(mtk_crtc->mutex);
  

• mtk_crtc_ddp_config(crtc);
  

• mtk_disp_mutex_release(mtk_crtc->mutex);
  

• }

+}

static void mtk_drm_crtc_atomic_enable(struct drm_crtc *crtc, struct drm_crtc_state *old_state) { diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.h b/drivers/gpu/drm/mediatek/mtk_drm_crtc.h index 6afe1c19557a..a2b4677a451c 100644 --- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.h +++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.h @@ -21,5 +21,7 @@ int mtk_drm_crtc_create(struct drm_device *drm_dev, unsigned int path_len); int mtk_drm_crtc_plane_check(struct drm_crtc *crtc, struct drm_plane *plane, struct mtk_plane_state *state); +void mtk_drm_crtc_async_update(struct drm_crtc *crtc, struct drm_plane *plane,

• 	       struct drm_plane_state *plane_state);
  
  

#endif /* MTK_DRM_CRTC_H */ diff --git a/drivers/gpu/drm/mediatek/mtk_drm_plane.c b/drivers/gpu/drm/mediatek/mtk_drm_plane.c index cd7c97eb7ee6..6bdb42f068fb 100644 --- a/drivers/gpu/drm/mediatek/mtk_drm_plane.c +++ b/drivers/gpu/drm/mediatek/mtk_drm_plane.c @@ -7,6 +7,7 @@ #include <drm/drm_atomic.h> #include <drm/drm_atomic_helper.h> #include <drm/drm_fourcc.h> +#include <drm/drm_atomic_uapi.h> #include <drm/drm_plane_helper.h> #include <drm/drm_gem_framebuffer_helper.h>

@@ -70,6 +71,50 @@ static void mtk_drm_plane_destroy_state(struct drm_plane *plane, kfree(to_mtk_plane_state(state)); }

+static int mtk_plane_atomic_async_check(struct drm_plane *plane,

• 			struct drm_plane_state *state)
  

+{

• struct drm_crtc_state *crtc_state;
• if (plane != state->crtc->cursor)

• return -EINVAL;
  

• if (!plane->state)

• return -EINVAL;
  

• if (!plane->state->fb)

• return -EINVAL;
  

• if (state->state)

• crtc_state = drm_atomic_get_existing_crtc_state(state->state,
  

• 						state->crtc);
  

• else /* Special case for asynchronous cursor updates. */

• crtc_state = state->crtc->state;
  

• return drm_atomic_helper_check_plane_state(plane->state, crtc_state,

• 				   DRM_PLANE_HELPER_NO_SCALING,
  

• 				   DRM_PLANE_HELPER_NO_SCALING,
  

• 				   true, true);
  

+}

+static void mtk_plane_atomic_async_update(struct drm_plane *plane,

• 			  struct drm_plane_state *new_state)
  

+{

• struct mtk_plane_state *state = to_mtk_plane_state(plane->state);
• plane->state->crtc_x = new_state->crtc_x;
• plane->state->crtc_y = new_state->crtc_y;
• plane->state->crtc_h = new_state->crtc_h;
• plane->state->crtc_w = new_state->crtc_w;
• plane->state->src_x = new_state->src_x;
• plane->state->src_y = new_state->src_y;
• plane->state->src_h = new_state->src_h;
• plane->state->src_w = new_state->src_w;
• state->pending.async_update = true;
• mtk_drm_crtc_async_update(new_state->crtc, plane, new_state);

+}

static const struct drm_plane_funcs mtk_plane_funcs = { .update_plane = drm_atomic_helper_update_plane, .disable_plane = drm_atomic_helper_disable_plane, @@ -141,6 +186,9 @@ static void mtk_plane_atomic_update(struct drm_plane *plane, state->pending.rotation = plane->state->rotation; wmb(); /* Make sure the above parameters are set before update */ state->pending.dirty = true;

• if (state->pending.async_update)

• state->pending.async_dirty = true;
  

}

static void mtk_plane_atomic_disable(struct drm_plane *plane, @@ -158,6 +206,8 @@ static const struct drm_plane_helper_funcs mtk_plane_helper_funcs = { .atomic_check = mtk_plane_atomic_check, .atomic_update = mtk_plane_atomic_update, .atomic_disable = mtk_plane_atomic_disable,

• .atomic_async_update = mtk_plane_atomic_async_update,
• .atomic_async_check = mtk_plane_atomic_async_check,

};

int mtk_plane_init(struct drm_device *dev, struct drm_plane *plane, diff --git a/drivers/gpu/drm/mediatek/mtk_drm_plane.h b/drivers/gpu/drm/mediatek/mtk_drm_plane.h index 760885e35b27..41882465dd67 100644 --- a/drivers/gpu/drm/mediatek/mtk_drm_plane.h +++ b/drivers/gpu/drm/mediatek/mtk_drm_plane.h @@ -22,6 +22,8 @@ struct mtk_plane_pending_state { unsigned int height; unsigned int rotation; bool dirty;

• bool async_dirty;
• bool async_update;

};

struct mtk_plane_state {