Re: [PATCH 04/14] drm: add helper to implement legacy dirtyfb

On Wed, Sep 05, 2018 at 04:38:51PM -0700, Deepak Rawat wrote:

From: Rob Clark robdclark@gmail.com

Add an atomic helper to implement dirtyfb support. This is needed to support DSI command-mode panels with x11 userspace (ie. when we can't rely on pageflips to trigger a flush to the panel).

v2: Modified the helper to use plane fb_damage_clips property and removed plane_state::dirty flag.

Signed-off-by: Rob Clark robdclark@gmail.com Signed-off-by: Deepak Rawat drawat@vmware.com

---

drivers/gpu/drm/drm_damage_helper.c | 116 ++++++++++++++++++++++++++++ include/drm/drm_damage_helper.h | 4 + 2 files changed, 120 insertions(+)

diff --git a/drivers/gpu/drm/drm_damage_helper.c b/drivers/gpu/drm/drm_damage_helper.c index 7d70f6001889..b016ec375295 100644 --- a/drivers/gpu/drm/drm_damage_helper.c +++ b/drivers/gpu/drm/drm_damage_helper.c @@ -26,6 +26,7 @@

• Authors:
• Deepak Rawat drawat@vmware.com

• • Rob Clark robdclark@gmail.com
  **************************************************************************/

@@ -81,6 +82,21 @@ static int convert_fixed_to_32(int fixed) return ((fixed >> 15) & 1) + (fixed >> 16); }

+static void convert_clip_rect_to_rect(const struct drm_clip_rect *src,

• 		      struct drm_rect *dest,
  

• 		      uint32_t num_clips)
  

I think we need to use drm_mode_rect here, because it's essentially the uapi one.

+{

• while (num_clips > 0) {

• dest->x1 = src->x1;
  

• dest->y1 = src->y1;
  

• dest->x2 = src->x2;
  

• dest->y2 = src->y2;
  

• src++;
  

• dest++;
  

• num_clips--;
  

• }

+}

/**

• drm_plane_enable_fb_damage_clips - enables plane fb damage clips property
• @plane: plane on which to enable damage clips property

@@ -183,3 +199,103 @@ drm_atomic_helper_damage_iter_next(struct drm_atomic_helper_damage_iter *iter, return ret; } EXPORT_SYMBOL(drm_atomic_helper_damage_iter_next);

+/**

• • drm_atomic_helper_dirtyfb - helper for dirtyfb
• • @fb: DRM framebuffer
• • @file_priv: drm file for the ioctl call
• • @flags: dirty fb annotate flags
• • @color: color for annotate fill
• • @clips: dirty region
• • @num_clips: count of clip in clips
• • A helper to implement drm_framebuffer_funcs::dirty. This helper will do a
• • full update in case of annotate flags.
• • Returns: Zero on success, negative errno on failure.
• */

+int drm_atomic_helper_dirtyfb(struct drm_framebuffer *fb,

• 	      struct drm_file *file_priv, unsigned flags,
  

• 	      unsigned color, struct drm_clip_rect *clips,
  

• 	      unsigned num_clips)
  

+{

• struct drm_modeset_acquire_ctx ctx;
• struct drm_property_blob *damage = NULL;
• struct drm_atomic_state *state;
• struct drm_plane *plane;
• struct drm_rect *rects = NULL;
• int ret = 0;
• /*

• * When called from ioctl, we are interruptable, but not when called
  

• * internally (ie. defio worker)
  

• */
  

• drm_modeset_acquire_init(&ctx,

• file_priv ? DRM_MODESET_ACQUIRE_INTERRUPTIBLE : 0);
  

• state = drm_atomic_state_alloc(fb->dev);
• if (!state) {

• ret = -ENOMEM;
  

• goto out;
  

• }
• state->acquire_ctx = &ctx;
• WARN_ONCE(flags & DRM_MODE_FB_DIRTY_FLAGS,

•   "Full update for dirtyfb with DRM_MODE_FB_DIRTY_FLAGS\n");
  

User-triggerable backtrace isn't good. I think you just need to handle the FILL/COPY meaning.

For COPY we need to ignore all the odd rects (iirc those are the sources). FILL we can just handle. See e.g. what tinydrm_merge_clips does.

Otherwise I think this looks good. -Daniel

• if (!(flags & DRM_MODE_FB_DIRTY_FLAGS)) {

• rects = kcalloc(num_clips, sizeof(*rects), GFP_KERNEL);
  

• if (!rects) {
  

• 	ret = -ENOMEM;
  

• 	goto out;
  

• }
  

• convert_clip_rect_to_rect(clips, rects, num_clips);
  

• damage = drm_property_create_blob(fb->dev,
  

• 				  num_clips * sizeof(*rects),
  

• 				  rects);
  

• if (IS_ERR(damage)) {
  

• 	ret = PTR_ERR(damage);
  

• 	damage = NULL;
  

• 	goto out;
  

• }
  

• }

+retry:

• drm_for_each_plane(plane, fb->dev) {

• struct drm_plane_state *plane_state;
  

• if (plane->state->fb != fb)
  

• 	continue;
  

• plane_state = drm_atomic_get_plane_state(state, plane);
  

• if (IS_ERR(plane_state)) {
  

• 	ret = PTR_ERR(plane_state);
  

• 	goto out;
  

• }
  

• drm_property_replace_blob(&plane_state->fb_damage_clips,
  

• 			  damage);
  

• }
• ret = drm_atomic_commit(state);

+out:

• if (ret == -EDEADLK) {

• drm_atomic_state_clear(state);
  

• ret = drm_modeset_backoff(&ctx);
  

• if (!ret)
  

• 	goto retry;
  

• }
• drm_property_blob_put(damage);
• kfree(rects);
• drm_atomic_state_put(state);
• drm_modeset_drop_locks(&ctx);
• drm_modeset_acquire_fini(&ctx);
• return ret;

+} +EXPORT_SYMBOL(drm_atomic_helper_dirtyfb); diff --git a/include/drm/drm_damage_helper.h b/include/drm/drm_damage_helper.h index 1f988f7fdd72..9d5c9444761b 100644 --- a/include/drm/drm_damage_helper.h +++ b/include/drm/drm_damage_helper.h @@ -89,5 +89,9 @@ drm_atomic_helper_damage_iter_init(struct drm_atomic_helper_damage_iter *iter, bool drm_atomic_helper_damage_iter_next(struct drm_atomic_helper_damage_iter *iter, struct drm_rect *rect); +int drm_atomic_helper_dirtyfb(struct drm_framebuffer *fb,

• 	      struct drm_file *file_priv, unsigned flags,
  

• 	      unsigned color, struct drm_clip_rect *clips,
  

• 	      unsigned num_clips);
  
  

#endif

2.17.1