FAILED: patch "[PATCH] drm/amd/display: Do not elevate mem_type change to full" failed to apply to 6.1-stable tree

FAILED: patch "[PATCH] drm/amd/display: Do not elevate mem_type change to full" failed to apply to 6.1-stable tree

[gregkh]

The patch below does not apply to the 6.1-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y
git checkout FETCH_HEAD
git cherry-pick -x 35ca53b7b0f0ffd16c6675fd76abac9409cf83e0
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2025012030-alongside-scenic-3cc9@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^..

Possible dependencies:



thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 35ca53b7b0f0ffd16c6675fd76abac9409cf83e0 Mon Sep 17 00:00:00 2001
From: Leo Li <sunpeng.li@amd.com>
Date: Wed, 11 Dec 2024 12:06:24 -0500
Subject: [PATCH] drm/amd/display: Do not elevate mem_type change to full
 update

[Why]

There should not be any need to revalidate bandwidth on memory placement
change, since the fb is expected to be pinned to DCN-accessable memory
before scanout. For APU it's DRAM, and DGPU, it's VRAM. However, async
flips + memory type change needs to be rejected.

[How]

Do not set lock_and_validation_needed on mem_type change. Instead,
reject an async_flip request if the crtc's buffer(s) changed mem_type.

This may fix stuttering/corruption experienced with PSR SU and PSR1
panels, if the compositor allocates fbs in both VRAM carveout and GTT
and flips between them.

Fixes: a7c0cad0dc06 ("drm/amd/display: ensure async flips are only accepted for fast updates")
Reviewed-by: Tom Chung <chiahsuan.chung@amd.com>
Signed-off-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Tom Chung <chiahsuan.chung@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit 4caacd1671b7a013ad04cd8b6398f002540bdd4d)
Cc: stable@vger.kernel.org

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index 56b47e02db0b..dcc5d8ded662 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -11379,6 +11379,25 @@ static int dm_crtc_get_cursor_mode(struct amdgpu_device *adev,
 	return 0;
 }
 
+static bool amdgpu_dm_crtc_mem_type_changed(struct drm_device *dev,
+					    struct drm_atomic_state *state,
+					    struct drm_crtc_state *crtc_state)
+{
+	struct drm_plane *plane;
+	struct drm_plane_state *new_plane_state, *old_plane_state;
+
+	drm_for_each_plane_mask(plane, dev, crtc_state->plane_mask) {
+		new_plane_state = drm_atomic_get_plane_state(state, plane);
+		old_plane_state = drm_atomic_get_plane_state(state, plane);
+
+		if (old_plane_state->fb && new_plane_state->fb &&
+		    get_mem_type(old_plane_state->fb) != get_mem_type(new_plane_state->fb))
+			return true;
+	}
+
+	return false;
+}
+
 /**
  * amdgpu_dm_atomic_check() - Atomic check implementation for AMDgpu DM.
  *
@@ -11576,10 +11595,6 @@ static int amdgpu_dm_atomic_check(struct drm_device *dev,
 
 	/* Remove exiting planes if they are modified */
 	for_each_oldnew_plane_in_descending_zpos(state, plane, old_plane_state, new_plane_state) {
-		if (old_plane_state->fb && new_plane_state->fb &&
-		    get_mem_type(old_plane_state->fb) !=
-		    get_mem_type(new_plane_state->fb))
-			lock_and_validation_needed = true;
 
 		ret = dm_update_plane_state(dc, state, plane,
 					    old_plane_state,
@@ -11874,9 +11889,11 @@ static int amdgpu_dm_atomic_check(struct drm_device *dev,
 
 		/*
 		 * Only allow async flips for fast updates that don't change
-		 * the FB pitch, the DCC state, rotation, etc.
+		 * the FB pitch, the DCC state, rotation, mem_type, etc.
 		 */
-		if (new_crtc_state->async_flip && lock_and_validation_needed) {
+		if (new_crtc_state->async_flip &&
+		    (lock_and_validation_needed ||
+		     amdgpu_dm_crtc_mem_type_changed(dev, state, new_crtc_state))) {
 			drm_dbg_atomic(crtc->dev,
 				       "[CRTC:%d:%s] async flips are only supported for fast updates\n",
 				       crtc->base.id, crtc->name);