FAILED: patch "[PATCH] scsi: ufs: core: Add a quirk to suppress link_startup_again" failed to apply to 6.6-stable tree

[<gregkh@linuxfoundation.org>]

The patch below does not apply to the 6.6-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-6.6.y
git checkout FETCH_HEAD
git cherry-pick -x d34caa89a132cd69efc48361d4772251546fdb88
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2025110906-retrieval-daunting-5fa7@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^..

Possible dependencies:



thanks,

greg k-h

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

From d34caa89a132cd69efc48361d4772251546fdb88 Mon Sep 17 00:00:00 2001
From: Adrian Hunter <adrian.hunter@intel.com>
Date: Fri, 24 Oct 2025 11:59:16 +0300
Subject: [PATCH] scsi: ufs: core: Add a quirk to suppress link_startup_again

ufshcd_link_startup() has a facility (link_startup_again) to issue
DME_LINKSTARTUP a 2nd time even though the 1st time was successful.

Some older hardware benefits from that, however the behaviour is
non-standard, and has been found to cause link startup to be unreliable
for some Intel Alder Lake based host controllers.

Add UFSHCD_QUIRK_PERFORM_LINK_STARTUP_ONCE to suppress
link_startup_again, in preparation for setting the quirk for affected
controllers.

Fixes: 7dc9fb47bc9a ("scsi: ufs: ufs-pci: Add support for Intel ADL")
Cc: stable@vger.kernel.org
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Link: https://patch.msgid.link/20251024085918.31825-3-adrian.hunter@intel.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
index 2b76f543d072..453a99ec6282 100644
--- a/drivers/ufs/core/ufshcd.c
+++ b/drivers/ufs/core/ufshcd.c
@@ -5066,7 +5066,8 @@ static int ufshcd_link_startup(struct ufs_hba *hba)
 	 * If UFS device isn't active then we will have to issue link startup
 	 * 2 times to make sure the device state move to active.
 	 */
-	if (!ufshcd_is_ufs_dev_active(hba))
+	if (!(hba->quirks & UFSHCD_QUIRK_PERFORM_LINK_STARTUP_ONCE) &&
+	    !ufshcd_is_ufs_dev_active(hba))
 		link_startup_again = true;
 
 link_startup:
diff --git a/include/ufs/ufshcd.h b/include/ufs/ufshcd.h
index 9425cfd9d00e..0f95576bf1f6 100644
--- a/include/ufs/ufshcd.h
+++ b/include/ufs/ufshcd.h
@@ -688,6 +688,13 @@ enum ufshcd_quirks {
 	 * single doorbell mode.
 	 */
 	UFSHCD_QUIRK_BROKEN_LSDBS_CAP			= 1 << 25,
+
+	/*
+	 * This quirk indicates that DME_LINKSTARTUP should not be issued a 2nd
+	 * time (refer link_startup_again) after the 1st time was successful,
+	 * because it causes link startup to become unreliable.
+	 */
+	UFSHCD_QUIRK_PERFORM_LINK_STARTUP_ONCE		= 1 << 26,
 };
 
 enum ufshcd_caps {