From 3c9ea68cb61bd7e5bd312c06a12adada74ff5805 Mon Sep 17 00:00:00 2001
From: Alvin Lee <alvin.lee2@amd.com>
Date: Mon, 6 Nov 2023 11:20:15 -0500
Subject: [PATCH] drm/amd/display: Include udelay when waiting for INBOX0 ACK
Git-commit: 3c9ea68cb61bd7e5bd312c06a12adada74ff5805
Patch-mainline: v6.7-rc4
References: git-fixes

When waiting for the ACK for INBOX0 message,
we have to ensure to include the udelay
for proper wait time

Cc: stable@vger.kernel.org # 6.1+
Reviewed-by: Samson Tam <samson.tam@amd.com>
Acked-by: Hamza Mahfooz <hamza.mahfooz@amd.com>
Signed-off-by: Alvin Lee <alvin.lee2@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/gpu/drm/amd/display/dmub/src/dmub_srv.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/gpu/drm/amd/display/dmub/src/dmub_srv.c b/drivers/gpu/drm/amd/display/dmub/src/dmub_srv.c
index 22fc4ba96def..38360adc53d9 100644
--- a/drivers/gpu/drm/amd/display/dmub/src/dmub_srv.c
+++ b/drivers/gpu/drm/amd/display/dmub/src/dmub_srv.c
@@ -1077,6 +1077,7 @@ enum dmub_status dmub_srv_wait_for_inbox0_ack(struct dmub_srv *dmub, uint32_t ti
 		ack = dmub->hw_funcs.read_inbox0_ack_register(dmub);
 		if (ack)
 			return DMUB_STATUS_OK;
+		udelay(1);
 	}
 	return DMUB_STATUS_TIMEOUT;
 }
-- 
2.43.0