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-rw-r--r--drivers/watchdog/Kconfig6
-rw-r--r--drivers/watchdog/Makefile1
-rw-r--r--drivers/watchdog/at91sam9_wdt.c109
3 files changed, 116 insertions, 0 deletions
diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index d9734ef588..cf83b6a15b 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -22,6 +22,12 @@ config WATCHDOG_AR9344
help
Add support for watchdog on the QCA AR9344 SoC.
+config WATCHDOG_AT91SAM9
+ bool "Watchdog for AT91SAM9 and SAMA5 SoCs"
+ depends on ARCH_AT91
+ help
+ Support for the watchdog in AT91SAM9X and SAMA5D{2,3,4} SoCs.
+
config WATCHDOG_EFI
bool "Generic EFI Watchdog Driver"
depends on EFI_BOOTUP
diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
index 3af64db3f2..dc9842770a 100644
--- a/drivers/watchdog/Makefile
+++ b/drivers/watchdog/Makefile
@@ -1,5 +1,6 @@
obj-$(CONFIG_WATCHDOG) += wd_core.o
obj-$(CONFIG_WATCHDOG_AR9344) += ar9344_wdt.o
+obj-$(CONFIG_WATCHDOG_AT91SAM9) += at91sam9_wdt.o
obj-$(CONFIG_WATCHDOG_EFI) += efi_wdt.o
obj-$(CONFIG_WATCHDOG_DAVINCI) += davinci_wdt.o
obj-$(CONFIG_WATCHDOG_OMAP) += omap_wdt.o
diff --git a/drivers/watchdog/at91sam9_wdt.c b/drivers/watchdog/at91sam9_wdt.c
new file mode 100644
index 0000000000..3f554bf47b
--- /dev/null
+++ b/drivers/watchdog/at91sam9_wdt.c
@@ -0,0 +1,109 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2019 Pengutronix, Ahmad Fatoum <a.fatoum@pengutronix.de>
+ */
+
+#include <common.h>
+#include <init.h>
+#include <io.h>
+#include <watchdog.h>
+#include <linux/clk.h>
+#include <mach/at91_wdt.h>
+
+#define MIN_WDT_TIMEOUT 1
+#define MAX_WDT_TIMEOUT 16
+#define SECS_TO_WDOG_TICKS(s) ((s) ? (((s) << 8) - 1) : 0)
+
+struct at91sam9x_wdt {
+ struct watchdog wdd;
+ void __iomem *base;
+};
+
+static inline void at91sam9x_wdt_ping(struct at91sam9x_wdt *wdt)
+{
+ writel(AT91_WDT_WDRSTT | AT91_WDT_KEY, wdt->base + AT91_WDT_CR);
+}
+
+static int at91sam9x_wdt_set_timeout(struct watchdog *wdd, unsigned timeout)
+{
+ struct at91sam9x_wdt *wdt = container_of(wdd, struct at91sam9x_wdt, wdd);
+ u32 mr_old, mr_new;
+
+ mr_old = readl(wdt->base + AT91_WDT_MR);
+
+ if (!timeout) {
+ mr_new = mr_old | AT91_WDT_WDDIS;
+ writel(mr_new, wdt->base + AT91_WDT_MR);
+ return 0;
+ }
+
+ mr_new = AT91_WDT_WDRSTEN
+ | AT91_WDT_WDDBGHLT | AT91_WDT_WDIDLEHLT
+ | AT91_WDT_WDD
+ | (SECS_TO_WDOG_TICKS(timeout) & AT91_WDT_WDV);
+
+ if (mr_new != mr_old)
+ writel(mr_new, wdt->base + AT91_WDT_MR);
+
+ at91sam9x_wdt_ping(wdt);
+ return 0;
+}
+
+static inline bool at91sam9x_wdt_is_disabled(struct at91sam9x_wdt *wdt)
+{
+ return readl(wdt->base + AT91_WDT_MR) & AT91_WDT_WDDIS;
+}
+
+static int at91sam9x_wdt_probe(struct device_d *dev)
+{
+ struct at91sam9x_wdt *wdt;
+ struct resource *iores;
+ struct clk *clk;
+ int ret;
+
+ wdt = xzalloc(sizeof(*wdt));
+ iores = dev_request_mem_resource(dev, 0);
+ if (IS_ERR(iores)) {
+ dev_err(dev, "could not get watchdog memory region\n");
+ return PTR_ERR(iores);
+ }
+ wdt->base = IOMEM(iores->start);
+ clk = clk_get(dev, NULL);
+ if (WARN_ON(IS_ERR(clk)))
+ return PTR_ERR(clk);
+
+ clk_enable(clk);
+
+ wdt->wdd.set_timeout = at91sam9x_wdt_set_timeout;
+ wdt->wdd.timeout_max = MAX_WDT_TIMEOUT;
+ wdt->wdd.hwdev = dev;
+
+ if (at91sam9x_wdt_is_disabled(wdt))
+ wdt->wdd.running = WDOG_HW_NOT_RUNNING;
+ else
+ wdt->wdd.running = WDOG_HW_RUNNING;
+
+ ret = watchdog_register(&wdt->wdd);
+ if (ret)
+ free(wdt);
+
+ return ret;
+}
+
+static const __maybe_unused struct of_device_id at91sam9x_wdt_dt_ids[] = {
+ { .compatible = "atmel,at91sam9260-wdt", },
+ { .compatible = "atmel,sama5d4-wdt", },
+ { /* sentinel */ },
+};
+
+static struct driver_d at91sam9x_wdt_driver = {
+ .name = "at91sam9x-wdt",
+ .of_compatible = DRV_OF_COMPAT(at91sam9x_wdt_dt_ids),
+ .probe = at91sam9x_wdt_probe,
+};
+
+static int __init at91sam9x_wdt_init(void)
+{
+ return platform_driver_register(&at91sam9x_wdt_driver);
+}
+device_initcall(at91sam9x_wdt_init);