From b90cef338f1e11e97ef4d180f2b4167af6d7da09 Mon Sep 17 00:00:00 2001
From: Jacky Bai <ping.bai@nxp.com>
Date: Mon, 18 Jan 2021 15:25:03 +0800
Subject: [PATCH] LF-3211 watchdog: imx7ulp: Add explict memory barrier for
 unlock sequence

Add explict memory barrier for the wdog unlock sequence.

Suggested-by: Ye Li <ye.li@nxp.com>
Signed-off-by: Jacky Bai <ping.bai@nxp.com>
Reviewed-by: Ye Li <ye.li@nxp.com>
(cherry picked from commit 59ec9bb1baaad40175aac6da16e1b000e5d5ee70)
Signed-off-by: Andrey Zhizhikin <andrey.zhizhikin@leica-geosystems.com>
---
 drivers/watchdog/imx7ulp_wdt.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/watchdog/imx7ulp_wdt.c b/drivers/watchdog/imx7ulp_wdt.c
index 014f497ea0dc..b8ac0cb04d2f 100644
--- a/drivers/watchdog/imx7ulp_wdt.c
+++ b/drivers/watchdog/imx7ulp_wdt.c
@@ -179,9 +179,13 @@ static int imx7ulp_wdt_init(void __iomem *base, unsigned int timeout)
 	int ret;
 
 	local_irq_disable();
+
+	mb();
 	/* unlock the wdog for reconfiguration */
 	writel_relaxed(UNLOCK_SEQ0, base + WDOG_CNT);
 	writel_relaxed(UNLOCK_SEQ1, base + WDOG_CNT);
+	mb();
+
 	ret = imx7ulp_wdt_wait(base, WDOG_CS_ULK);
 	if (ret)
 		goto init_out;