staging: drm/omap: defer unpin until scanout completes

When flipping, defer unpinning until scanout completes, as indicated
by the appropriate END_WIN irq.

This also re-organizes things a bit, in replacing omap_fb_{pin,unpin}
with omap_fb_replace(), to make it easier to add support for scanout
synchronized DMM refill mode (flipping by just reprogramming DMM
synchronized with DSS scanout).

Signed-off-by: Rob Clark <rob@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 49 insertions, 35 deletions

diff --git a/drivers/staging/omapdrm/omap_fb.c b/drivers/staging/omapdrm/omap_fb.c
index 08e2e35..fcb248f 100644
--- a/drivers/staging/omapdrm/omap_fb.c
+++ b/drivers/staging/omapdrm/omap_fb.c
@@ -137,41 +137,6 @@ static const struct drm_framebuffer_funcs omap_framebuffer_funcs = {
 	.dirty = omap_framebuffer_dirty,
 };
 
-/* pins buffer in preparation for scanout */
-int omap_framebuffer_pin(struct drm_framebuffer *fb)
-{
-	struct omap_framebuffer *omap_fb = to_omap_framebuffer(fb);
-	int ret, i, n = drm_format_num_planes(omap_fb->format->pixel_format);
-
-	for (i = 0; i < n; i++) {
-		struct plane *plane = &omap_fb->planes[i];
-		ret = omap_gem_get_paddr(plane->bo, &plane->paddr, true);
-		if (ret)
-			goto fail;
-	}
-
-	return 0;
-
-fail:
-	while (--i > 0) {
-		struct plane *plane = &omap_fb->planes[i];
-		omap_gem_put_paddr(plane->bo);
-	}
-	return ret;
-}
-
-/* releases buffer when done with scanout */
-void omap_framebuffer_unpin(struct drm_framebuffer *fb)
-{
-	struct omap_framebuffer *omap_fb = to_omap_framebuffer(fb);
-	int i, n = drm_format_num_planes(omap_fb->format->pixel_format);
-
-	for (i = 0; i < n; i++) {
-		struct plane *plane = &omap_fb->planes[i];
-		omap_gem_put_paddr(plane->bo);
-	}
-}
-
 /* update ovl info for scanout, handles cases of multi-planar fb's, etc.
  */
 void omap_framebuffer_update_scanout(struct drm_framebuffer *fb, int x, int y,
@@ -201,6 +166,55 @@ void omap_framebuffer_update_scanout(struct drm_framebuffer *fb, int x, int y,
 	}
 }
 
+/* Call for unpin 'a' (if not NULL), and pin 'b' (if not NULL).  Although
+ * buffers to unpin are just just pushed to the unpin fifo so that the
+ * caller can defer unpin until vblank.
+ *
+ * Note if this fails (ie. something went very wrong!), all buffers are
+ * unpinned, and the caller disables the overlay.  We could have tried
+ * to revert back to the previous set of pinned buffers but if things are
+ * hosed there is no guarantee that would succeed.
+ */
+int omap_framebuffer_replace(struct drm_framebuffer *a,
+		struct drm_framebuffer *b, void *arg,
+		void (*unpin)(void *arg, struct drm_gem_object *bo))
+{
+	int ret = 0, i, na, nb;
+	struct omap_framebuffer *ofba = to_omap_framebuffer(a);
+	struct omap_framebuffer *ofbb = to_omap_framebuffer(b);
+
+	na = a ? drm_format_num_planes(a->pixel_format) : 0;
+	nb = b ? drm_format_num_planes(b->pixel_format) : 0;
+
+	for (i = 0; i < max(na, nb); i++) {
+		struct plane *pa, *pb;
+
+		pa = (i < na) ? &ofba->planes[i] : NULL;
+		pb = (i < nb) ? &ofbb->planes[i] : NULL;
+
+		if (pa) {
+			unpin(arg, pa->bo);
+			pa->paddr = 0;
+		}
+
+		if (pb && !ret)
+			ret = omap_gem_get_paddr(pb->bo, &pb->paddr, true);
+	}
+
+	if (ret) {
+		/* something went wrong.. unpin what has been pinned */
+		for (i = 0; i < nb; i++) {
+			struct plane *pb = &ofba->planes[i];
+			if (pb->paddr) {
+				unpin(arg, pb->bo);
+				pb->paddr = 0;
+			}
+		}
+	}
+
+	return ret;
+}
+
 struct drm_gem_object *omap_framebuffer_bo(struct drm_framebuffer *fb, int p)
 {
 	struct omap_framebuffer *omap_fb = to_omap_framebuffer(fb);