From:   Rob Clark <robdclark@gmail.com>
To:     dri-devel@lists.freedesktop.org
Cc:     freedreno@lists.freedesktop.org, intel-gfx@lists.freedesktop.org,
        Luben Tuikov <luben.tuikov@amd.com>,
        =?UTF-8?q?Christian=20K=C3=B6nig?= 
        <ckoenig.leichtzumerken@gmail.com>,
        Rodrigo Vivi <rodrigo.vivi@intel.com>,
        Matt Turner <mattst88@gmail.com>,
        Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>,
        Rob Clark <robdclark@chromium.org>,
        Daniel Vetter <daniel.vetter@ffwll.ch>,
        Maarten Lankhorst <maarten.lankhorst@linux.intel.com>,
        Maxime Ripard <mripard@kernel.org>,
        Thomas Zimmermann <tzimmermann@suse.de>,
        David Airlie <airlied@gmail.com>,
        Daniel Vetter <daniel@ffwll.ch>,
        linux-kernel@vger.kernel.org (open list)
Subject: [PATCH v10 11/15] drm/atomic-helper: Set fence deadline for vblank
Date:   Wed,  8 Mar 2023 07:53:02 -0800
Message-Id: <20230308155322.344664-12-robdclark@gmail.com>
In-Reply-To: <20230308155322.344664-1-robdclark@gmail.com>
References: <20230308155322.344664-1-robdclark@gmail.com>
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From: Rob Clark <robdclark@chromium.org>

For an atomic commit updating a single CRTC (ie. a pageflip) calculate
the next vblank time, and inform the fence(s) of that deadline.

v2: Comment typo fix (danvet)
v3: If there are multiple CRTCs, consider the time of the soonest vblank

Signed-off-by: Rob Clark <robdclark@chromium.org>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Rob Clark <robdclark@chromium.org>
---
 drivers/gpu/drm/drm_atomic_helper.c | 37 +++++++++++++++++++++++++++++
 1 file changed, 37 insertions(+)

diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c
index d579fd8f7cb8..28e3f2c8917e 100644
--- a/drivers/gpu/drm/drm_atomic_helper.c
+++ b/drivers/gpu/drm/drm_atomic_helper.c
@@ -1511,6 +1511,41 @@ void drm_atomic_helper_commit_modeset_enables(struct drm_device *dev,
 }
 EXPORT_SYMBOL(drm_atomic_helper_commit_modeset_enables);
 
+/*
+ * For atomic updates which touch just a single CRTC, calculate the time of the
+ * next vblank, and inform all the fences of the deadline.
+ */
+static void set_fence_deadline(struct drm_device *dev,
+			       struct drm_atomic_state *state)
+{
+	struct drm_crtc *crtc;
+	struct drm_crtc_state *new_crtc_state;
+	struct drm_plane *plane;
+	struct drm_plane_state *new_plane_state;
+	ktime_t vbltime = 0;
+	int i;
+
+	for_each_new_crtc_in_state (state, crtc, new_crtc_state, i) {
+		ktime_t v;
+
+		if (drm_crtc_next_vblank_start(crtc, &v))
+			continue;
+
+		if (!vbltime || ktime_before(v, vbltime))
+			vbltime = v;
+	}
+
+	/* If no CRTCs updated, then nothing to do: */
+	if (!vbltime)
+		return;
+
+	for_each_new_plane_in_state (state, plane, new_plane_state, i) {
+		if (!new_plane_state->fence)
+			continue;
+		dma_fence_set_deadline(new_plane_state->fence, vbltime);
+	}
+}
+
 /**
  * drm_atomic_helper_wait_for_fences - wait for fences stashed in plane state
  * @dev: DRM device
@@ -1540,6 +1575,8 @@ int drm_atomic_helper_wait_for_fences(struct drm_device *dev,
 	struct drm_plane_state *new_plane_state;
 	int i, ret;
 
+	set_fence_deadline(dev, state);
+
 	for_each_new_plane_in_state(state, plane, new_plane_state, i) {
 		if (!new_plane_state->fence)
 			continue;
-- 
2.39.2