Revert "watchdog: iTCO_wdt: Account for rebooting on second timeout"

This reverts commit 39ed17de8c6ff54c7ed4605a4a8e04a2e2f0b82e which is
commit cb011044e34c293e139570ce5c01aed66a34345c upstream.

It is reported to cause problems with systems and probably should not
have been backported in the first place :(

Link: https://lore.kernel.org/r/20210803165108.4154cd52@endymion
Reported-by: Jean Delvare <jdelvare@suse.de>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Wim Van Sebroeck <wim@linux-watchdog.org>
Cc: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/watchdog/iTCO_wdt.c b/drivers/watchdog/iTCO_wdt.c
index 519a539eeb9e8891d6297c84f89da1c52de774ad..a370a185a41c40811a8f0f3002b17f4678d91264 100644 (file)
--- a/drivers/watchdog/iTCO_wdt.c
+++ b/drivers/watchdog/iTCO_wdt.c
@@ -73,8 +73,6 @@
 #define TCOBASE(p)     ((p)->tco_res->start)
 /* SMI Control and Enable Register */
 #define SMI_EN(p)      ((p)->smi_res->start)
-#define TCO_EN         (1 << 13)
-#define GBL_SMI_EN     (1 << 0)
 
 #define TCO_RLD(p)     (TCOBASE(p) + 0x00) /* TCO Timer Reload/Curr. Value */
 #define TCOv1_TMR(p)   (TCOBASE(p) + 0x01) /* TCOv1 Timer Initial Value*/
@@ -359,12 +357,8 @@ static int iTCO_wdt_set_timeout(struct watchdog_device *wd_dev, unsigned int t)
 
        tmrval = seconds_to_ticks(p, t);
 
-       /*
-        * If TCO SMIs are off, the timer counts down twice before rebooting.
-        * Otherwise, the BIOS generally reboots when the SMI triggers.
-        */
-       if (p->smi_res &&
-           (SMI_EN(p) & (TCO_EN | GBL_SMI_EN)) != (TCO_EN | GBL_SMI_EN))
+       /* For TCO v1 the timer counts down twice before rebooting */
+       if (p->iTCO_version == 1)
                tmrval /= 2;
 
        /* from the specs: */
@@ -529,7 +523,7 @@ static int iTCO_wdt_probe(struct platform_device *pdev)
                 * Disables TCO logic generating an SMI#
                 */
                val32 = inl(SMI_EN(p));
-               val32 &= ~TCO_EN;       /* Turn off SMI clearing watchdog */
+               val32 &= 0xffffdfff;    /* Turn off SMI clearing watchdog */
                outl(val32, SMI_EN(p));
        }