4.14-stable review patch. If anyone has any objections, please let me know.
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From: Milton Miller miltonm@us.ibm.com
[ Upstream commit 6ffa3402211acc30e47e691e14d62f3fd065a54e ]
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.
Also clear the secondary boot bit during the machine restart operation. Otherwise, the system will switch to the alternate boot after every reboot, which is not desired.
Signed-off-by: Milton Miller miltonm@us.ibm.com Signed-off-by: Eddie James eajames@linux.vnet.ibm.com Reviewed-by: Joel Stanley joel@jms.id.au Reviewed-by: Guenter Roeck linux@roeck-us.net Signed-off-by: Guenter Roeck linux@roeck-us.net Signed-off-by: Wim Van Sebroeck wim@iguana.be Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/watchdog/aspeed_wdt.c | 4 ++++ 1 file changed, 4 insertions(+)
--- a/drivers/watchdog/aspeed_wdt.c +++ b/drivers/watchdog/aspeed_wdt.c @@ -46,6 +46,7 @@ MODULE_DEVICE_TABLE(of, aspeed_wdt_of_ta #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) @@ -158,6 +159,7 @@ static int aspeed_wdt_restart(struct wat { struct aspeed_wdt *wdt = to_aspeed_wdt(wdd);
+ wdt->ctrl &= ~WDT_CTRL_BOOT_SECONDARY; aspeed_wdt_enable(wdt, 128 * WDT_RATE_1MHZ / 1000);
mdelay(1000); @@ -242,6 +244,8 @@ static int aspeed_wdt_probe(struct platf } 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;
writel(wdt->ctrl, wdt->base + WDT_CTRL);