diff options
Diffstat (limited to 'drivers/watchdog/bcm2835_wdt.c')
| -rw-r--r-- | drivers/watchdog/bcm2835_wdt.c | 49 |
1 files changed, 27 insertions, 22 deletions
diff --git a/drivers/watchdog/bcm2835_wdt.c b/drivers/watchdog/bcm2835_wdt.c index dec6ca019bea..62937e6f83ca 100644 --- a/drivers/watchdog/bcm2835_wdt.c +++ b/drivers/watchdog/bcm2835_wdt.c @@ -32,13 +32,7 @@ #define PM_RSTC_WRCFG_SET 0x00000030 #define PM_RSTC_WRCFG_FULL_RESET 0x00000020 #define PM_RSTC_RESET 0x00000102 - -/* - * The Raspberry Pi firmware uses the RSTS register to know which partition - * to boot from. The partition value is spread into bits 0, 2, 4, 6, 8, 10. - * Partition 63 is a special partition used by the firmware to indicate halt. - */ -#define PM_RSTS_RASPBERRYPI_HALT 0x555 +#define PM_RSTS_PARTITION_CLR 0xfffffaaa #define SECS_TO_WDOG_TICKS(x) ((x) << 16) #define WDOG_TICKS_TO_SECS(x) ((x) >> 16) @@ -97,9 +91,24 @@ static unsigned int bcm2835_wdt_get_timeleft(struct watchdog_device *wdog) return WDOG_TICKS_TO_SECS(ret & PM_WDOG_TIME_SET); } -static void __bcm2835_restart(struct bcm2835_wdt *wdt) +/* + * The Raspberry Pi firmware uses the RSTS register to know which partiton + * to boot from. The partiton value is spread into bits 0, 2, 4, 6, 8, 10. + * Partiton 63 is a special partition used by the firmware to indicate halt. + */ + +static void __bcm2835_restart(struct bcm2835_wdt *wdt, u8 partition) { - u32 val; + u32 val, rsts; + + rsts = (partition & BIT(0)) | ((partition & BIT(1)) << 1) | + ((partition & BIT(2)) << 2) | ((partition & BIT(3)) << 3) | + ((partition & BIT(4)) << 4) | ((partition & BIT(5)) << 5); + + val = readl_relaxed(wdt->base + PM_RSTS); + val &= PM_RSTS_PARTITION_CLR; + val |= PM_PASSWORD | rsts; + writel_relaxed(val, wdt->base + PM_RSTS); /* use a timeout of 10 ticks (~150us) */ writel_relaxed(10 | PM_PASSWORD, wdt->base + PM_WDOG); @@ -117,7 +126,13 @@ static int bcm2835_restart(struct watchdog_device *wdog, { struct bcm2835_wdt *wdt = watchdog_get_drvdata(wdog); - __bcm2835_restart(wdt); + unsigned long long val; + u8 partition = 0; + + if (data && !kstrtoull(data, 0, &val) && val <= 63) + partition = val; + + __bcm2835_restart(wdt, partition); return 0; } @@ -152,19 +167,9 @@ static struct watchdog_device bcm2835_wdt_wdd = { static void bcm2835_power_off(void) { struct bcm2835_wdt *wdt = bcm2835_power_off_wdt; - u32 val; - - /* - * We set the watchdog hard reset bit here to distinguish this reset - * from the normal (full) reset. bootcode.bin will not reboot after a - * hard reset. - */ - val = readl_relaxed(wdt->base + PM_RSTS); - val |= PM_PASSWORD | PM_RSTS_RASPBERRYPI_HALT; - writel_relaxed(val, wdt->base + PM_RSTS); - /* Continue with normal reset mechanism */ - __bcm2835_restart(wdt); + /* Partition 63 tells the firmware that this is a halt */ + __bcm2835_restart(wdt, 63); } static int bcm2835_wdt_probe(struct platform_device *pdev) |