[PATCH 4.19 14/16] Revert "watchdog: iTCO_wdt: Account for rebooting on second timeout"

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

This reverts commit 5bfbacfeadf864cb23dfe66c610ed036d5e48879 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>
---
 drivers/watchdog/iTCO_wdt.c |   12 +++---------
 1 file changed, 3 insertions(+), 9 deletions(-)

--- a/drivers/watchdog/iTCO_wdt.c
+++ b/drivers/watchdog/iTCO_wdt.c
@@ -75,8 +75,6 @@
 #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*/
@@ -332,12 +330,8 @@ static int iTCO_wdt_set_timeout(struct w
 
 	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: */
@@ -499,7 +493,7 @@ static int iTCO_wdt_probe(struct platfor
 		 * 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));
 	}