watchdog: imx_sc_wdt: Pretimeout should follow SCU firmware format

[ Upstream commit 2c50a6b825b3463a7600d6e6acadba73211c3d2c ]

SCU firmware calculates pretimeout based on current time stamp
instead of watchdog timeout stamp, need to convert the pretimeout
to SCU firmware's timeout value.

Fixes: 15f7d7fc5542 ("watchdog: imx_sc: Add pretimeout support")
Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/watchdog/imx_sc_wdt.c b/drivers/watchdog/imx_sc_wdt.c
index 78eaaf75a263f369c99ef62c300004f695eea79f..9545d1e07421a5d358858e8d14c99aa6677f4401 100644 (file)
--- a/drivers/watchdog/imx_sc_wdt.c
+++ b/drivers/watchdog/imx_sc_wdt.c
@@ -99,8 +99,14 @@ static int imx_sc_wdt_set_pretimeout(struct watchdog_device *wdog,
 {
        struct arm_smccc_res res;
 
+       /*
+        * SCU firmware calculates pretimeout based on current time
+        * stamp instead of watchdog timeout stamp, need to convert
+        * the pretimeout to SCU firmware's timeout value.
+        */
        arm_smccc_smc(IMX_SIP_TIMER, IMX_SIP_TIMER_SET_PRETIME_WDOG,
-                     pretimeout * 1000, 0, 0, 0, 0, 0, &res);
+                     (wdog->timeout - pretimeout) * 1000, 0, 0, 0,
+                     0, 0, &res);
        if (res.a0)
                return -EACCES;