diff options
Diffstat (limited to 'drivers/watchdog/cdns_wdt.c')
| -rw-r--r-- | drivers/watchdog/cdns_wdt.c | 41 |
1 files changed, 40 insertions, 1 deletions
diff --git a/drivers/watchdog/cdns_wdt.c b/drivers/watchdog/cdns_wdt.c index 966d010e40d..6dfdd31c8b8 100644 --- a/drivers/watchdog/cdns_wdt.c +++ b/drivers/watchdog/cdns_wdt.c @@ -215,6 +215,45 @@ static int cdns_wdt_stop(struct udevice *dev) } /** + * cdns_wdt_expire_now - Expire the watchdog. + * + * @dev: Watchdog device + * @flags: Driver flags + * + * Access WDT and configure with minimal counter value to expire ASAP. + * Expiration issues system reset. When DEBUG is enabled count should be + * bigger to at least see debug message. + * + * Return: Always 0 + */ +static int cdns_wdt_expire_now(struct udevice *dev, ulong flags) +{ + struct cdns_wdt_priv *priv = dev_get_priv(dev); + u32 data, count = 0; + +#if defined(DEBUG) + count = 0x40; /* Increase the value if you need more time */ + debug("%s: Expire wdt%u\n", __func__, dev_seq(dev)); +#endif + + cdns_wdt_writereg(&priv->regs->zmr, CDNS_WDT_ZMR_ZKEY_VAL); + + count = (count << 2) & CDNS_WDT_CCR_CRV_MASK; + + /* Write counter access key first to be able write to register */ + data = count | CDNS_WDT_REGISTER_ACCESS_KEY; + cdns_wdt_writereg(&priv->regs->ccr, data); + + data = CDNS_WDT_ZMR_WDEN_MASK | CDNS_WDT_ZMR_RSTEN_MASK | + CDNS_WDT_ZMR_ZKEY_VAL; + + cdns_wdt_writereg(&priv->regs->zmr, data); + cdns_wdt_writereg(&priv->regs->restart, CDNS_WDT_RESTART_KEY); + + return 0; +} + +/** * cdns_wdt_probe - Probe call for the device. * * @dev: Handle to the udevice structure. @@ -247,7 +286,7 @@ static const struct wdt_ops cdns_wdt_ops = { .start = cdns_wdt_start, .reset = cdns_wdt_reset, .stop = cdns_wdt_stop, - /* There is no bit/reg/support in IP for expire_now functionality */ + .expire_now = cdns_wdt_expire_now, }; static const struct udevice_id cdns_wdt_ids[] = { |