From 71d1f058844de6052835549f06c113f5014a8290 Mon Sep 17 00:00:00 2001 From: David Lechner Date: Mon, 11 Dec 2017 11:21:08 -0600 Subject: watchdog: davinci_wdt: add restart function This adds a restart function to the davinci watchdog timer driver. This is copied from arch/arm/mach-davinci/time.c and will allow us to remove the code from there. Signed-off-by: David Lechner Reviewed-by: Guenter Roeck Signed-off-by: Guenter Roeck Signed-off-by: Wim Van Sebroeck --- drivers/watchdog/davinci_wdt.c | 38 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 38 insertions(+) diff --git a/drivers/watchdog/davinci_wdt.c b/drivers/watchdog/davinci_wdt.c index 2f46487af86d..3e4c592c239f 100644 --- a/drivers/watchdog/davinci_wdt.c +++ b/drivers/watchdog/davinci_wdt.c @@ -140,6 +140,42 @@ static unsigned int davinci_wdt_get_timeleft(struct watchdog_device *wdd) return wdd->timeout - timer_counter; } +static int davinci_wdt_restart(struct watchdog_device *wdd, + unsigned long action, void *data) +{ + struct davinci_wdt_device *davinci_wdt = watchdog_get_drvdata(wdd); + u32 tgcr, wdtcr; + + /* disable, internal clock source */ + iowrite32(0, davinci_wdt->base + TCR); + + /* reset timer, set mode to 64-bit watchdog, and unreset */ + tgcr = 0; + iowrite32(tgcr, davinci_wdt->base + TGCR); + tgcr = TIMMODE_64BIT_WDOG | TIM12RS_UNRESET | TIM34RS_UNRESET; + iowrite32(tgcr, davinci_wdt->base + TGCR); + + /* clear counter and period regs */ + iowrite32(0, davinci_wdt->base + TIM12); + iowrite32(0, davinci_wdt->base + TIM34); + iowrite32(0, davinci_wdt->base + PRD12); + iowrite32(0, davinci_wdt->base + PRD34); + + /* put watchdog in pre-active state */ + wdtcr = WDKEY_SEQ0 | WDEN; + iowrite32(wdtcr, davinci_wdt->base + WDTCR); + + /* put watchdog in active state */ + wdtcr = WDKEY_SEQ1 | WDEN; + iowrite32(wdtcr, davinci_wdt->base + WDTCR); + + /* write an invalid value to the WDKEY field to trigger a restart */ + wdtcr = 0x00004000; + iowrite32(wdtcr, davinci_wdt->base + WDTCR); + + return 0; +} + static const struct watchdog_info davinci_wdt_info = { .options = WDIOF_KEEPALIVEPING, .identity = "DaVinci/Keystone Watchdog", @@ -151,6 +187,7 @@ static const struct watchdog_ops davinci_wdt_ops = { .stop = davinci_wdt_ping, .ping = davinci_wdt_ping, .get_timeleft = davinci_wdt_get_timeleft, + .restart = davinci_wdt_restart, }; static int davinci_wdt_probe(struct platform_device *pdev) @@ -195,6 +232,7 @@ static int davinci_wdt_probe(struct platform_device *pdev) watchdog_set_drvdata(wdd, davinci_wdt); watchdog_set_nowayout(wdd, 1); + watchdog_set_restart_priority(wdd, 128); wdt_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); davinci_wdt->base = devm_ioremap_resource(dev, wdt_mem); -- cgit v1.2.3