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-rw-r--r--drivers/watchdog/orion_wdt.c123
1 files changed, 123 insertions, 0 deletions
diff --git a/drivers/watchdog/orion_wdt.c b/drivers/watchdog/orion_wdt.c
new file mode 100644
index 0000000000..2802033f71
--- /dev/null
+++ b/drivers/watchdog/orion_wdt.c
@@ -0,0 +1,123 @@
+/*
+ * Watchdog driver for Marvell Armada XP.
+ *
+ * Copyright (C) 2017 Pengutronix, Uwe Kleine-König <kernel@pengutronix.de>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <common.h>
+#include <errno.h>
+#include <init.h>
+#include <io.h>
+#include <malloc.h>
+#include <of.h>
+#include <watchdog.h>
+
+#define CLKRATE 25000000
+
+/* registers relative to timer_base (i.e. first reg property) */
+#define TIMER_CTRL 0x00
+#define TIMER_CTRL_WD_TIMER_25MHZ_EN BIT(10)
+#define TIMER_CTRL_WD_TIMER_EN BIT(8)
+
+#define TIMER_STATUS 0x04
+#define TIMER_STATUS_WD_EXPIRED BIT(31)
+
+#define TIMER_WD_TIMER 0x34
+
+/* registers relative to rstout_base (i.e. second reg property) */
+#define WD_RSTOUTn_MASK 0x00
+#define WD_RSTOUTn_MASK_GLOBAL_WD BIT(8)
+
+struct orion_wdt_ddata {
+ struct watchdog wd;
+ void __iomem *timer_base;
+ void __iomem *rstout_base;
+};
+
+static int armada_xp_set_timeout(struct watchdog *wd, unsigned timeout)
+{
+ struct orion_wdt_ddata *ddata =
+ container_of(wd, struct orion_wdt_ddata, wd);
+ u32 ctrl;
+
+ if (0xffffffff / CLKRATE < timeout)
+ return -EINVAL;
+
+ ctrl = readl(ddata->timer_base + TIMER_CTRL);
+
+ if (timeout == 0) {
+ /* disable timer */
+ ctrl &= ~TIMER_CTRL_WD_TIMER_EN;
+ writel(ctrl, ddata->timer_base + TIMER_CTRL);
+
+ return 0;
+ }
+
+ /* setup duration */
+ writel(CLKRATE * timeout, ddata->timer_base + TIMER_WD_TIMER);
+
+ /* clear expiration status */
+ writel(readl(ddata->timer_base + TIMER_STATUS) & ~TIMER_STATUS_WD_EXPIRED,
+ ddata->timer_base + TIMER_STATUS);
+
+ /* assert reset on expiration */
+ writel(WD_RSTOUTn_MASK_GLOBAL_WD, ddata->rstout_base + WD_RSTOUTn_MASK);
+
+ /* enable */
+ ctrl |= TIMER_CTRL_WD_TIMER_25MHZ_EN | TIMER_CTRL_WD_TIMER_EN;
+ writel(ctrl, ddata->timer_base + TIMER_CTRL);
+
+ return 0;
+}
+
+static int orion_wdt_probe(struct device_d *dev)
+{
+ struct orion_wdt_ddata* ddata;
+ struct resource *res_timer, *res_rstout;
+
+ ddata = xzalloc(sizeof(*ddata));
+
+ ddata->wd.set_timeout = armada_xp_set_timeout;
+ ddata->wd.name = "orion_wdt";
+ ddata->wd.dev = dev;
+
+ res_timer = dev_request_mem_resource(dev, 0);
+ if (IS_ERR(res_timer)) {
+ dev_err(dev, "could not get timer memory region\n");
+ return PTR_ERR(res_timer);
+ }
+ ddata->timer_base = IOMEM(res_timer->start);
+
+ res_rstout = dev_request_mem_resource(dev, 1);
+ if (IS_ERR(res_rstout)) {
+ dev_err(dev, "could not get rstout memory region\n");
+ release_region(res_timer);
+
+ return PTR_ERR(res_rstout);
+ }
+ ddata->rstout_base = IOMEM(res_rstout->start);
+
+ return watchdog_register(&ddata->wd);
+}
+
+static const struct of_device_id orion_wdt_of_match[] = {
+ {
+ .compatible = "marvell,armada-xp-wdt",
+ }, { /* sentinel */ }
+};
+
+static struct driver_d orion_wdt_driver = {
+ .probe = orion_wdt_probe,
+ .name = "orion_wdt",
+ .of_compatible = DRV_OF_COMPAT(orion_wdt_of_match),
+};
+device_platform_driver(orion_wdt_driver);