1 files changed, 102 insertions, 0 deletions
diff --git a/drivers/watchdog/jz4740.c b/drivers/watchdog/jz4740.c
new file mode 100644
index 0000000000..8ac51e060a
--- /dev/null
+++ b/drivers/watchdog/jz4740.c
@@ -0,0 +1,102 @@
+/*
+ *  JZ4740 Watchdog driver
+ *
+ *  Copyright (C) 2014 Antony Pavlov <antonynpavlov@gmail.com>
+ *
+ *  Based on jz4740_wdt.c from linux-3.15.
+ *
+ *  Copyright (C) 2010, Paul Cercueil <paul@crapouillou.net>
+ *
+ *  This program is free software; you can redistribute it and/or modify it
+ *  under  the terms of the GNU General  Public License as published by the
+ *  Free Software Foundation;  either version 2 of the License, or (at your
+ *  option) any later version.
+ *
+ */
+
+#include <common.h>
+#include <init.h>
+#include <io.h>
+
+#define JZ_REG_WDT_TIMER_DATA     0x0
+#define JZ_REG_WDT_COUNTER_ENABLE 0x4
+#define JZ_REG_WDT_TIMER_COUNTER  0x8
+#define JZ_REG_WDT_TIMER_CONTROL  0xC
+
+#define JZ_WDT_CLOCK_PCLK 0x1
+#define JZ_WDT_CLOCK_RTC  0x2
+#define JZ_WDT_CLOCK_EXT  0x4
+
+#define JZ_WDT_CLOCK_DIV_SHIFT   3
+
+#define JZ_WDT_CLOCK_DIV_1    (0 << JZ_WDT_CLOCK_DIV_SHIFT)
+#define JZ_WDT_CLOCK_DIV_4    (1 << JZ_WDT_CLOCK_DIV_SHIFT)
+#define JZ_WDT_CLOCK_DIV_16   (2 << JZ_WDT_CLOCK_DIV_SHIFT)
+#define JZ_WDT_CLOCK_DIV_64   (3 << JZ_WDT_CLOCK_DIV_SHIFT)
+#define JZ_WDT_CLOCK_DIV_256  (4 << JZ_WDT_CLOCK_DIV_SHIFT)
+#define JZ_WDT_CLOCK_DIV_1024 (5 << JZ_WDT_CLOCK_DIV_SHIFT)
+
+#define JZ_EXTAL 24000000
+
+struct jz4740_wdt_drvdata {
+	void __iomem *base;
+};
+
+static struct jz4740_wdt_drvdata *reset_wd;
+
+void __noreturn reset_cpu(unsigned long addr)
+{
+	if (reset_wd) {
+		void __iomem *base = reset_wd->base;
+
+		writew(JZ_WDT_CLOCK_DIV_4 | JZ_WDT_CLOCK_EXT,
+				base + JZ_REG_WDT_TIMER_CONTROL);
+		writew(0, base + JZ_REG_WDT_TIMER_COUNTER);
+
+		/* reset after 4ms */
+		writew(JZ_EXTAL / 1000, base + JZ_REG_WDT_TIMER_DATA);
+
+		/* start wdt */
+		writeb(0x1, base + JZ_REG_WDT_COUNTER_ENABLE);
+
+		mdelay(1000);
+	} else
+		pr_err("%s: can't reset cpu\n", __func__);
+
+	hang();
+}
+EXPORT_SYMBOL(reset_cpu);
+
+static int jz4740_wdt_probe(struct device_d *dev)
+{
+	struct jz4740_wdt_drvdata *priv;
+
+	priv = xzalloc(sizeof(struct jz4740_wdt_drvdata));
+	priv->base = dev_request_mem_region(dev, 0);
+	if (!priv->base) {
+		dev_err(dev, "could not get memory region\n");
+		return -ENODEV;
+	}
+
+	if (!reset_wd)
+		reset_wd = priv;
+
+	dev->priv = priv;
+
+	return 0;
+}
+
+static __maybe_unused struct of_device_id jz4740_wdt_dt_ids[] = {
+	{
+		.compatible = "ingenic,jz4740-wdt",
+	}, {
+		/* sentinel */
+	}
+};
+
+static struct driver_d jz4740_wdt_driver = {
+	.name   = "jz4740-wdt",
+	.probe  = jz4740_wdt_probe,
+	.of_compatible = DRV_OF_COMPAT(jz4740_wdt_dt_ids),
+};
+device_platform_driver(jz4740_wdt_driver);