[Intel-gfx] [PATCH 3/7] drm: Extract page_flip_{internal, atomic}()

[Ville Syrjala]

From: Ville Syrjälä <ville.syrjala at linux.intel.com>

Yank out the code for the plane->fb/old_fb/crtc handling from
the page flip path into page_flip_internal(), and provide a
simpler variant for atomic drivers.

We'll also move the fb vs. src viewport checks into the new
functions as they are slightly different between the two paths.
If the atomic .page_flip() implementations are guaranteed
to call drm_atomic_plane_check() we could even drop the check
entirely from page_flip_atomic(). For now toss in a FIXME.

v2: Bit more polish in page_flip_internal()

Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
---
 drivers/gpu/drm/drm_plane.c | 159 +++++++++++++++++++++++-------------
 1 file changed, 102 insertions(+), 57 deletions(-)

diff --git a/drivers/gpu/drm/drm_plane.c b/drivers/gpu/drm/drm_plane.c
index 38878da5b704..6052475a20a5 100644
--- a/drivers/gpu/drm/drm_plane.c
+++ b/drivers/gpu/drm/drm_plane.c
@@ -1031,13 +1031,109 @@ int drm_mode_cursor2_ioctl(struct drm_device *dev,
 	return drm_mode_cursor_common(dev, req, file_priv);
 }
 
+static int page_flip_check_fbs(const struct drm_framebuffer *fb,
+			       const struct drm_framebuffer *old_fb)
+{
+	/* The framebuffer is currently unbound, presumably
+	 * due to a hotplug event, that userspace has not
+	 * yet discovered.
+	 */
+	if (!old_fb)
+		return -EBUSY;
+
+	if (old_fb->format != fb->format) {
+		DRM_DEBUG_KMS("Page flip is not allowed to change frame buffer format.\n");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int page_flip_internal(struct drm_crtc *crtc,
+			      struct drm_framebuffer *fb,
+			      struct drm_pending_vblank_event *e,
+			      u32 flags,
+			      u32 target_vblank,
+			      struct drm_modeset_acquire_ctx *ctx)
+{
+	struct drm_plane *plane = crtc->primary;
+	int ret;
+
+	WARN_ON(drm_drv_uses_atomic_modeset(crtc->dev));
+
+	ret = drm_crtc_check_viewport(crtc, crtc->x, crtc->y,
+				      &crtc->mode, fb);
+	if (ret)
+		return ret;
+
+	ret = page_flip_check_fbs(fb, plane->fb);
+	if (ret)
+		return ret;
+
+	plane->old_fb = plane->fb;
+	if (crtc->funcs->page_flip_target)
+		ret = crtc->funcs->page_flip_target(crtc, fb, e, flags,
+						    target_vblank, ctx);
+	else
+		ret = crtc->funcs->page_flip(crtc, fb, e, flags, ctx);
+	if (ret) {
+		plane->old_fb = NULL;
+		return ret;
+	}
+
+	plane->fb = fb;
+	drm_framebuffer_get(plane->fb);
+
+	drm_framebuffer_put(plane->old_fb);
+	plane->old_fb = NULL;
+
+	return 0;
+}
+
+static int page_flip_atomic(struct drm_crtc *crtc,
+			    struct drm_framebuffer *fb,
+			    struct drm_pending_vblank_event *e,
+			    u32 flags,
+			    u32 target_vblank,
+			    struct drm_modeset_acquire_ctx *ctx)
+{
+	struct drm_plane *plane = crtc->primary;
+	struct drm_plane_state *plane_state = plane->state;
+	int ret;
+
+	WARN_ON(!drm_drv_uses_atomic_modeset(crtc->dev));
+
+	/*
+	 * FIXME: Can we assume all drivers end up calling
+	 * drm_atomic_plane_check() in their page flip paths?
+	 * If so we could remove this.
+	 */
+	ret = drm_framebuffer_check_src_coords(plane_state->src_x,
+					       plane_state->src_y,
+					       plane_state->src_w,
+					       plane_state->src_h,
+					       fb);
+	if (ret)
+		return ret;
+
+	ret = page_flip_check_fbs(fb, plane_state->fb);
+	if (ret)
+		return ret;
+
+	if (crtc->funcs->page_flip_target)
+		return crtc->funcs->page_flip_target(crtc, fb, e, flags,
+						     target_vblank, ctx);
+	else
+		return crtc->funcs->page_flip(crtc, fb, e, flags, ctx);
+}
+
 int drm_mode_page_flip_ioctl(struct drm_device *dev,
 			     void *data, struct drm_file *file_priv)
 {
 	struct drm_mode_crtc_page_flip_target *page_flip = data;
 	struct drm_crtc *crtc;
 	struct drm_plane *plane;
-	struct drm_framebuffer *fb, *old_fb;
+	struct drm_framebuffer *fb;
 	struct drm_pending_vblank_event *e = NULL;
 	u32 target_vblank = page_flip->sequence;
 	struct drm_modeset_acquire_ctx ctx;
@@ -1145,65 +1241,14 @@ int drm_mode_page_flip_ioctl(struct drm_device *dev,
 	if (ret)
 		goto out;
 
-	if (plane->state)
-		old_fb = plane->state->fb;
+	if (drm_drv_uses_atomic_modeset(dev))
+		ret = page_flip_atomic(crtc, fb, e, page_flip->flags,
+				       target_vblank, &ctx);
 	else
-		old_fb = plane->fb;
-
-	if (old_fb == NULL) {
-		/* The framebuffer is currently unbound, presumably
-		 * due to a hotplug event, that userspace has not
-		 * yet discovered.
-		 */
-		ret = -EBUSY;
-		goto out;
-	}
-
-	if (plane->state) {
-		const struct drm_plane_state *state = plane->state;
-
-		ret = drm_framebuffer_check_src_coords(state->src_x,
-						       state->src_y,
-						       state->src_w,
-						       state->src_h,
-						       fb);
-	} else {
-		ret = drm_crtc_check_viewport(crtc, crtc->x, crtc->y,
-					      &crtc->mode, fb);
-	}
-	if (ret)
-		goto out;
-
-	if (old_fb->format != fb->format) {
-		DRM_DEBUG_KMS("Page flip is not allowed to change frame buffer format.\n");
-		ret = -EINVAL;
-		goto out;
-	}
-
-	plane->old_fb = plane->fb;
-	if (crtc->funcs->page_flip_target)
-		ret = crtc->funcs->page_flip_target(crtc, fb, e,
-						    page_flip->flags,
-						    target_vblank,
-						    &ctx);
-	else
-		ret = crtc->funcs->page_flip(crtc, fb, e, page_flip->flags,
-					     &ctx);
-	if (ret) {
-		/* Keep the old fb, don't unref it. */
-		plane->old_fb = NULL;
-	} else {
-		if (!plane->state) {
-			plane->fb = fb;
-			drm_framebuffer_get(fb);
-		}
-	}
+		ret = page_flip_internal(crtc, fb, e, page_flip->flags,
+					 target_vblank, &ctx);
 
 out:
-	if (plane->old_fb)
-		drm_framebuffer_put(plane->old_fb);
-	plane->old_fb = NULL;
-
 	if (ret == -EDEADLK) {
 		ret = drm_modeset_backoff(&ctx);
 		if (!ret)
-- 
2.23.0