[PATCH linux dev-4.13 2/3] watchdog: aspeed: Allow configuring for alternate boot

[Eddie James]

From: Milton Miller <miltonm at us.ibm.com>

Allow the device tree to specify a watchdog to fallover to
the alternate boot source.

The aspeeed watchdog can set a latch directing flash chip select 0 to
chip select 1, allowing boot from an alternate media if the watchdog
is not reset in time.  On the ast2400 bank 1 also goes to flash bank 1,
while on the ast2500 the chip selects are swapped.

Signed-off-by: Milton Miller <miltonm at us.ibm.com>
Signed-off-by: Eddie James <eajames at linux.vnet.ibm.com>
---
 drivers/watchdog/aspeed_wdt.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/watchdog/aspeed_wdt.c b/drivers/watchdog/aspeed_wdt.c
index d1987d6..f41d246 100644
--- a/drivers/watchdog/aspeed_wdt.c
+++ b/drivers/watchdog/aspeed_wdt.c
@@ -46,6 +46,7 @@ struct aspeed_wdt_config {
 #define WDT_RELOAD_VALUE	0x04
 #define WDT_RESTART		0x08
 #define WDT_CTRL		0x0C
+#define   WDT_CTRL_BOOT_SECONDARY	BIT(7)
 #define   WDT_CTRL_RESET_MODE_SOC	(0x00 << 5)
 #define   WDT_CTRL_RESET_MODE_FULL_CHIP	(0x01 << 5)
 #define   WDT_CTRL_RESET_MODE_ARM_CPU	(0x10 << 5)
@@ -245,6 +246,8 @@ static int aspeed_wdt_probe(struct platform_device *pdev)
 	}
 	if (of_property_read_bool(np, "aspeed,external-signal"))
 		wdt->ctrl |= WDT_CTRL_WDT_EXT;
+	if (of_property_read_bool(np, "aspeed,alt-boot"))
+		wdt->ctrl |= WDT_CTRL_BOOT_SECONDARY;
 
 	if (readl(wdt->base + WDT_CTRL) & WDT_CTRL_ENABLE)  {
 		/*
-- 
1.8.3.1