mowgli: disable flash side switch on watchdog (#202)

There is an unknown deadlock occurring intermittently in mowgli when
the host starts. The ideal recovery from this is to simply reset the
BMC and stay on the current side of BMC flash.

Currently, the hardware watchdog triggers a BMC flash switch during
the reboot. This patch removes the flash side switch but keeps the
reboot behavior.

Tested:
- Injected a watchdog hit during host boot and verified BMC came
  back up on same flash side and host was still up and running fine

Signed-off-by: Andrew Geissler <geissonator@yahoo.com>

meta-ibm/meta-witherspoon/recipes-kernel/linux/linux-aspeed/0001-dts-mowgli-disable-flash-side-switch-on-watchdog.patch

@@ -0,0 +1,32 @@
+From 053e60ef43555eebe21d49ae7bebdfd55232193a Mon Sep 17 00:00:00 2001
+From: Andrew Geissler <geissonator@yahoo.com>
+Date: Tue, 16 Nov 2021 15:55:13 +0000
+Subject: [PATCH] dts:mowgli: disable flash side switch on watchdog
+
+This feature is causing more confusion that solutions. Just have the
+watchdog reset the BMC and continue running on the current side of
+flash.
+
+Signed-off-by: Andrew Geissler <geissonator@yahoo.com>
+---
+ arch/arm/boot/dts/aspeed-bmc-opp-mowgli.dts | 4 ----
+ 1 file changed, 4 deletions(-)
+
+diff --git a/arch/arm/boot/dts/aspeed-bmc-opp-mowgli.dts b/arch/arm/boot/dts/aspeed-bmc-opp-mowgli.dts
+index f5b9027e13e0..141e1d61fd5b 100644
+--- a/arch/arm/boot/dts/aspeed-bmc-opp-mowgli.dts
++++ b/arch/arm/boot/dts/aspeed-bmc-opp-mowgli.dts
+@@ -647,10 +647,6 @@
+ 	pinctrl-0 = <&pinctrl_wdtrst1_default>;
+ };
+
+-&wdt2 {
+-	aspeed,alt-boot;
+-};
+-
+ &ibt {
+ 	status = "okay";
+ };
+-- 
+2.25.1
+

meta-ibm/meta-witherspoon/recipes-kernel/linux/linux-aspeed_%.bbappend

@@ -5,4 +5,5 @@ SRC_URI_append_mihawk += " file://0001-wistron-wps.patch"
 SRC_URI_append_mowgli += " file://mowgli.cfg"
 SRC_URI_append_mowgli += " file://0001-Fix-psu-signal-and-vout-issue.patch"
 SRC_URI_append_mowgli += " file://0001-Add-mowgli-platform.patch"
+SRC_URI_append_mowgli += " file://0001-dts-mowgli-disable-flash-side-switch-on-watchdog.patch"
 SRC_URI_append_witherspoon-128 = " file://0001-ARM-dts-Aspeed-Witherspoon-128-Update-BMC-partitioni.patch"