FAILED: patch "[PATCH] drm/amd/display: Use HW lock mgr for PSR1 when only one eDP" failed to apply to 6.1-stable tree

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 <[email protected]>.

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 acbf16a6ae775b4db86f537448cc466288aa307e
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2025032440-purifier-stand-0619@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^..

Possible dependencies:

thanks,

greg k-h

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

From acbf16a6ae775b4db86f537448cc466288aa307e Mon Sep 17 00:00:00 2001
From: Mario Limonciello <[email protected]>
Date: Fri, 7 Mar 2025 15:55:20 -0600
Subject: [PATCH] drm/amd/display: Use HW lock mgr for PSR1 when only one eDP

[WHY]
DMUB locking is important to make sure that registers aren't accessed while in PSR. Previously it was enabled but caused a deadlock in situations with multiple eDP panels.

[HOW]
Detect if multiple eDP panels are in use to decide whether to use lock. Refactor the function so that the first check is for PSR-SU and then replay is in use to prevent having to look up number of eDP panels for those configurations.

index bf636b28e3e1..6e2fce329d73 100644
@@ -69,5 +69,16 @@ bool should_use_dmub_lock(struct dc_link *link)
 	if (link->replay_settings.replay_feature_enabled)
 		return true;
 
+	/* only use HW lock for PSR1 on single eDP */
+	if (link->psr_settings.psr_version == DC_PSR_VERSION_1) {
+		struct dc_link *edp_links[MAX_NUM_EDP];
+		int edp_num;
+
+		dc_get_edp_links(link->dc, edp_links, &edp_num);
+
+		if (edp_num == 1)
+			return true;
+	}
+
 	return false;
 }