drm/vc4: kms: Convert to atomic helpers

Now that the semaphore is gone, our atomic_commit implementation is
basically drm_atomic_helper_commit with a somewhat custom commit_tail,
the main difference being that we're using wait_for_flip_done instead of
wait_for_vblanks used in the drm_atomic_helper_commit_tail helper.

Let's switch to using drm_atomic_helper_commit.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20201204151138.1739736-8-maxime@cerno.tech

diff --git a/drivers/gpu/drm/vc4/vc4_kms.c b/drivers/gpu/drm/vc4/vc4_kms.c
index 48d07ea..f09254c 100644 (file)
--- a/drivers/gpu/drm/vc4/vc4_kms.c
+++ b/drivers/gpu/drm/vc4/vc4_kms.c
@@ -332,8 +332,7 @@ static void vc5_hvs_pv_muxing_commit(struct vc4_dev *vc4,
        }
 }
 
-static void
-vc4_atomic_complete_commit(struct drm_atomic_state *state)
+static void vc4_atomic_commit_tail(struct drm_atomic_state *state)
 {
        struct drm_device *dev = state->dev;
        struct vc4_dev *vc4 = to_vc4_dev(dev);
@@ -357,10 +356,6 @@ vc4_atomic_complete_commit(struct drm_atomic_state *state)
        if (vc4->hvs->hvs5)
                clk_set_min_rate(hvs->core_clk, 500000000);
 
-       drm_atomic_helper_wait_for_fences(dev, state, false);
-
-       drm_atomic_helper_wait_for_dependencies(state);
-
        old_hvs_state = vc4_hvs_get_old_global_state(state);
        if (!old_hvs_state)
                return;
@@ -412,20 +407,8 @@ vc4_atomic_complete_commit(struct drm_atomic_state *state)
 
        drm_atomic_helper_cleanup_planes(dev, state);
 
-       drm_atomic_helper_commit_cleanup_done(state);
-
        if (vc4->hvs->hvs5)
                clk_set_min_rate(hvs->core_clk, 0);
-
-       drm_atomic_state_put(state);
-}
-
-static void commit_work(struct work_struct *work)
-{
-       struct drm_atomic_state *state = container_of(work,
-                                                     struct drm_atomic_state,
-                                                     commit_work);
-       vc4_atomic_complete_commit(state);
 }
 
 static int vc4_atomic_commit_setup(struct drm_atomic_state *state)
@@ -458,94 +441,6 @@ static int vc4_atomic_commit_setup(struct drm_atomic_state *state)
        return 0;
 }
 
-/**
- * vc4_atomic_commit - commit validated state object
- * @dev: DRM device
- * @state: the driver state object
- * @nonblock: nonblocking commit
- *
- * This function commits a with drm_atomic_helper_check() pre-validated state
- * object. This can still fail when e.g. the framebuffer reservation fails. For
- * now this doesn't implement asynchronous commits.
- *
- * RETURNS
- * Zero for success or -errno.
- */
-static int vc4_atomic_commit(struct drm_device *dev,
-                            struct drm_atomic_state *state,
-                            bool nonblock)
-{
-       int ret;
-
-       if (state->async_update) {
-               ret = drm_atomic_helper_prepare_planes(dev, state);
-               if (ret)
-                       return ret;
-
-               drm_atomic_helper_async_commit(dev, state);
-
-               drm_atomic_helper_cleanup_planes(dev, state);
-
-               return 0;
-       }
-
-       /* We know for sure we don't want an async update here. Set
-        * state->legacy_cursor_update to false to prevent
-        * drm_atomic_helper_setup_commit() from auto-completing
-        * commit->flip_done.
-        */
-       state->legacy_cursor_update = false;
-       ret = drm_atomic_helper_setup_commit(state, nonblock);
-       if (ret)
-               return ret;
-
-       INIT_WORK(&state->commit_work, commit_work);
-
-       ret = drm_atomic_helper_prepare_planes(dev, state);
-       if (ret)
-               return ret;
-
-       if (!nonblock) {
-               ret = drm_atomic_helper_wait_for_fences(dev, state, true);
-               if (ret) {
-                       drm_atomic_helper_cleanup_planes(dev, state);
-                       return ret;
-               }
-       }
-
-       /*
-        * This is the point of no return - everything below never fails except
-        * when the hw goes bonghits. Which means we can commit the new state on
-        * the software side now.
-        */
-
-       BUG_ON(drm_atomic_helper_swap_state(state, false) < 0);
-
-       /*
-        * Everything below can be run asynchronously without the need to grab
-        * any modeset locks at all under one condition: It must be guaranteed
-        * that the asynchronous work has either been cancelled (if the driver
-        * supports it, which at least requires that the framebuffers get
-        * cleaned up with drm_atomic_helper_cleanup_planes()) or completed
-        * before the new state gets committed on the software side with
-        * drm_atomic_helper_swap_state().
-        *
-        * This scheme allows new atomic state updates to be prepared and
-        * checked in parallel to the asynchronous completion of the previous
-        * update. Which is important since compositors need to figure out the
-        * composition of the next frame right after having submitted the
-        * current layout.
-        */
-
-       drm_atomic_state_get(state);
-       if (nonblock)
-               queue_work(system_unbound_wq, &state->commit_work);
-       else
-               vc4_atomic_complete_commit(state);
-
-       return 0;
-}
-
 static struct drm_framebuffer *vc4_fb_create(struct drm_device *dev,
                                             struct drm_file *file_priv,
                                             const struct drm_mode_fb_cmd2 *mode_cmd)
@@ -966,11 +861,12 @@ vc4_atomic_check(struct drm_device *dev, struct drm_atomic_state *state)
 
 static struct drm_mode_config_helper_funcs vc4_mode_config_helpers = {
        .atomic_commit_setup    = vc4_atomic_commit_setup,
+       .atomic_commit_tail     = vc4_atomic_commit_tail,
 };
 
 static const struct drm_mode_config_funcs vc4_mode_funcs = {
        .atomic_check = vc4_atomic_check,
-       .atomic_commit = vc4_atomic_commit,
+       .atomic_commit = drm_atomic_helper_commit,
        .fb_create = vc4_fb_create,
 };