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 <david@lechnology.com>
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>
This commit is contained in:
David Lechner 2017-12-11 11:21:08 -06:00 committed by Wim Van Sebroeck
parent 8bc86475a0
commit 71d1f05884
1 changed files with 38 additions and 0 deletions

View File

@ -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);