1 files changed, 93 insertions, 0 deletions
diff --git a/drivers/watchdog/kvx_wdt.c b/drivers/watchdog/kvx_wdt.c
new file mode 100644
index 0000000000..be6b08b71c
--- /dev/null
+++ b/drivers/watchdog/kvx_wdt.c
@@ -0,0 +1,93 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2018 Kalray Inc.
+ */
+
+#include <common.h>
+#include <init.h>
+#include <io.h>
+#include <of.h>
+#include <watchdog.h>
+
+#include <linux/clk.h>
+#include <linux/err.h>
+
+#include <asm/sfr.h>
+
+struct kvx_wdt {
+	uint64_t clk_rate;
+	struct watchdog wdd;
+};
+
+static void kvx_watchdog_disable(void)
+{
+	kvx_sfr_set_field(TCR, WUI, 0);
+	kvx_sfr_set_field(TCR, WCE, 0);
+}
+
+static int kvx_wdt_set_timeout(struct watchdog *wdd, unsigned int timeout)
+{
+	struct kvx_wdt *wdt = container_of(wdd, struct kvx_wdt, wdd);
+	uint64_t cycle_timeout = wdt->clk_rate * timeout;
+
+	/* Disable watchdog */
+	if (timeout == 0) {
+		kvx_watchdog_disable();
+		return 0;
+	}
+
+	kvx_sfr_set(WDV, cycle_timeout);
+	kvx_sfr_set(WDR, 0);
+
+	/* Start watchdog counting */
+	kvx_sfr_set_field(TCR, WUI, 1);
+	kvx_sfr_set_field(TCR, WCE, 1);
+
+	return 0;
+}
+
+static int count;
+
+static int kvx_wdt_drv_probe(struct device *dev)
+{
+	struct watchdog *wdd;
+	struct clk *clk;
+	struct kvx_wdt *kvx_wdt;
+
+	if (count != 0) {
+		dev_warn(dev, "Tried to register core watchdog twice\n");
+		return -EINVAL;
+	}
+	count++;
+
+	kvx_wdt = xzalloc(sizeof(*kvx_wdt));
+	clk = clk_get(dev, NULL);
+	if (IS_ERR(clk))
+		return PTR_ERR(clk);
+
+	kvx_wdt->clk_rate = clk_get_rate(clk);
+	clk_put(clk);
+
+	wdd = &kvx_wdt->wdd;
+	wdd->name = "kvx_wdt";
+	wdd->hwdev = dev;
+	wdd->set_timeout = kvx_wdt_set_timeout;
+
+	/* Be sure that interrupt are disabled */
+	kvx_sfr_set_field(TCR, WIE, 0);
+
+	return watchdog_register(wdd);
+}
+
+static struct of_device_id kvx_wdt_of_match[] = {
+	{ .compatible = "kalray,kvx-core-watchdog", },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, kvx_wdt_of_match);
+
+static struct driver kvx_wdt_driver = {
+	.name		= "kvx-wdt",
+	.probe		= kvx_wdt_drv_probe,
+	.of_compatible	= DRV_OF_COMPAT(kvx_wdt_of_match),
+};
+device_platform_driver(kvx_wdt_driver);