diff options
Diffstat (limited to 'drivers/watchdog/renesas_wdt.c')
| -rw-r--r-- | drivers/watchdog/renesas_wdt.c | 87 |
1 files changed, 82 insertions, 5 deletions
diff --git a/drivers/watchdog/renesas_wdt.c b/drivers/watchdog/renesas_wdt.c index 831ef83f6de1..6b8c6ddfe30b 100644 --- a/drivers/watchdog/renesas_wdt.c +++ b/drivers/watchdog/renesas_wdt.c @@ -16,6 +16,8 @@ #include <linux/of.h> #include <linux/platform_device.h> #include <linux/pm_runtime.h> +#include <linux/smp.h> +#include <linux/sys_soc.h> #include <linux/watchdog.h> #define RWTCNT 0 @@ -49,6 +51,7 @@ struct rwdt_priv { void __iomem *base; struct watchdog_device wdev; unsigned long clk_rate; + u16 time_left; u8 cks; }; @@ -107,6 +110,16 @@ static unsigned int rwdt_get_timeleft(struct watchdog_device *wdev) return DIV_BY_CLKS_PER_SEC(priv, 65536 - val); } +static int rwdt_restart(struct watchdog_device *wdev, unsigned long action, + void *data) +{ + struct rwdt_priv *priv = watchdog_get_drvdata(wdev); + + rwdt_start(wdev); + rwdt_write(priv, 0xffff, RWTCNT); + return 0; +} + static const struct watchdog_info rwdt_ident = { .options = WDIOF_MAGICCLOSE | WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT, .identity = "Renesas WDT Watchdog", @@ -118,8 +131,47 @@ static const struct watchdog_ops rwdt_ops = { .stop = rwdt_stop, .ping = rwdt_init_timeout, .get_timeleft = rwdt_get_timeleft, + .restart = rwdt_restart, }; +#if defined(CONFIG_ARCH_RCAR_GEN2) && defined(CONFIG_SMP) +/* + * Watchdog-reset integration is broken on early revisions of R-Car Gen2 SoCs + */ +static const struct soc_device_attribute rwdt_quirks_match[] = { + { + .soc_id = "r8a7790", + .revision = "ES1.*", + .data = (void *)1, /* needs single CPU */ + }, { + .soc_id = "r8a7791", + .revision = "ES[12].*", + .data = (void *)1, /* needs single CPU */ + }, { + .soc_id = "r8a7792", + .revision = "*", + .data = (void *)0, /* needs SMP disabled */ + }, + { /* sentinel */ } +}; + +static bool rwdt_blacklisted(struct device *dev) +{ + const struct soc_device_attribute *attr; + + attr = soc_device_match(rwdt_quirks_match); + if (attr && setup_max_cpus > (uintptr_t)attr->data) { + dev_info(dev, "Watchdog blacklisted on %s %s\n", attr->soc_id, + attr->revision); + return true; + } + + return false; +} +#else /* !CONFIG_ARCH_RCAR_GEN2 || !CONFIG_SMP */ +static inline bool rwdt_blacklisted(struct device *dev) { return false; } +#endif /* !CONFIG_ARCH_RCAR_GEN2 || !CONFIG_SMP */ + static int rwdt_probe(struct platform_device *pdev) { struct rwdt_priv *priv; @@ -128,6 +180,9 @@ static int rwdt_probe(struct platform_device *pdev) unsigned long clks_per_sec; int ret, i; + if (rwdt_blacklisted(&pdev->dev)) + return -ENODEV; + priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); if (!priv) return -ENOMEM; @@ -176,6 +231,7 @@ static int rwdt_probe(struct platform_device *pdev) platform_set_drvdata(pdev, priv); watchdog_set_drvdata(&priv->wdev, priv); watchdog_set_nowayout(&priv->wdev, nowayout); + watchdog_set_restart_priority(&priv->wdev, 0); /* This overrides the default timeout only if DT configuration was found */ ret = watchdog_init_timeout(&priv->wdev, 0, &pdev->dev); @@ -203,12 +259,32 @@ static int rwdt_remove(struct platform_device *pdev) return 0; } -/* - * This driver does also fit for R-Car Gen2 (r8a779[0-4]) WDT. However, for SMP - * to work there, one also needs a RESET (RST) driver which does not exist yet - * due to HW issues. This needs to be solved before adding compatibles here. - */ +static int __maybe_unused rwdt_suspend(struct device *dev) +{ + struct rwdt_priv *priv = dev_get_drvdata(dev); + + if (watchdog_active(&priv->wdev)) { + priv->time_left = readw(priv->base + RWTCNT); + rwdt_stop(&priv->wdev); + } + return 0; +} + +static int __maybe_unused rwdt_resume(struct device *dev) +{ + struct rwdt_priv *priv = dev_get_drvdata(dev); + + if (watchdog_active(&priv->wdev)) { + rwdt_start(&priv->wdev); + rwdt_write(priv, priv->time_left, RWTCNT); + } + return 0; +} + +static SIMPLE_DEV_PM_OPS(rwdt_pm_ops, rwdt_suspend, rwdt_resume); + static const struct of_device_id rwdt_ids[] = { + { .compatible = "renesas,rcar-gen2-wdt", }, { .compatible = "renesas,rcar-gen3-wdt", }, { /* sentinel */ } }; @@ -218,6 +294,7 @@ static struct platform_driver rwdt_driver = { .driver = { .name = "renesas_wdt", .of_match_table = rwdt_ids, + .pm = &rwdt_pm_ops, }, .probe = rwdt_probe, .remove = rwdt_remove, |