[PATCH 4/6][SRU][OEM-5.17] drm/mgag200: Optimize damage clips

[AceLan Kao]

From: Jocelyn Falempe <jfalempe at redhat.com>

BugLink: https://launchpad.net/bugs/1995573

When there are multiple damage clips, previous code merged them into one
big rectangle. As the Matrox memory is very slow, it's faster to copy each
damage clip.

Signed-off-by: Jocelyn Falempe <jfalempe at redhat.com>
Reviewed-by: Lyude Paul <lyude at redhat.com>
Reviewed-by: Thomas Zimmermann <tzimmermann at suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20220504134026.283417-2-jfalempe@redhat.com
(cherry picked from commit c48a363016349352dac7e66cd1e823f73bff1fc4)
Signed-off-by: Chia-Lin Kao (AceLan) <acelan.kao at canonical.com>
---
 drivers/gpu/drm/mgag200/mgag200_mode.c | 16 +++++++++++-----
 1 file changed, 11 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/mgag200/mgag200_mode.c b/drivers/gpu/drm/mgag200/mgag200_mode.c
index 4bdc1fc388a9..4c09485d3ef8 100644
--- a/drivers/gpu/drm/mgag200/mgag200_mode.c
+++ b/drivers/gpu/drm/mgag200/mgag200_mode.c
@@ -865,10 +865,6 @@ mgag200_handle_damage(struct mga_device *mdev, struct drm_framebuffer *fb,
 
 	dst += drm_fb_clip_offset(fb->pitches[0], fb->format, clip);
 	drm_fb_memcpy_toio(dst, fb->pitches[0], vmap, fb, clip);
-
-	/* Always scanout image at VRAM offset 0 */
-	mgag200_set_startadd(mdev, (u32)0);
-	mgag200_set_offset(mdev, fb);
 }
 
 static void
@@ -923,6 +919,10 @@ mgag200_simple_display_pipe_enable(struct drm_simple_display_pipe *pipe,
 
 	mgag200_handle_damage(mdev, fb, &fullscreen, &shadow_plane_state->data[0]);
 
+	/* Always scanout image at VRAM offset 0 */
+	mgag200_set_startadd(mdev, (u32)0);
+	mgag200_set_offset(mdev, fb);
+
 	mutex_unlock(&mdev->rmmio_lock);
 }
 
@@ -979,14 +979,20 @@ mgag200_simple_display_pipe_update(struct drm_simple_display_pipe *pipe,
 	struct drm_shadow_plane_state *shadow_plane_state = to_drm_shadow_plane_state(state);
 	struct drm_framebuffer *fb = state->fb;
 	struct drm_rect damage;
+	struct drm_atomic_helper_damage_iter iter;
 
 	if (!fb)
 		return;
 
 	mutex_lock(&mdev->rmmio_lock);
 
-	if (drm_atomic_helper_damage_merged(old_state, state, &damage))
+	drm_atomic_helper_damage_iter_init(&iter, old_state, state);
+	drm_atomic_for_each_plane_damage(&iter, &damage) {
 		mgag200_handle_damage(mdev, fb, &damage, &shadow_plane_state->data[0]);
+	}
+	/* Always scanout image at VRAM offset 0 */
+	mgag200_set_startadd(mdev, (u32)0);
+	mgag200_set_offset(mdev, fb);
 
 	mutex_unlock(&mdev->rmmio_lock);
 }
-- 
2.34.1