1 files changed, 85 insertions, 0 deletions

diff --git a/drivers/power/reset/sun6i-reboot.c b/drivers/power/reset/sun6i-reboot.c
new file mode 100644
index 000000000000..af2cd7ff2fe8
--- /dev/null
+++ b/drivers/power/reset/sun6i-reboot.c
@@ -0,0 +1,85 @@
+/*
+ * Allwinner A31 SoCs reset code
+ *
+ * Copyright (C) 2012-2014 Maxime Ripard
+ *
+ * Maxime Ripard <maxime.ripard@free-electrons.com>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2.  This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/platform_device.h>
+#include <linux/reboot.h>
+
+#include <asm/system_misc.h>
+
+#define SUN6I_WATCHDOG1_IRQ_REG         0x00
+#define SUN6I_WATCHDOG1_CTRL_REG        0x10
+#define SUN6I_WATCHDOG1_CTRL_RESTART            BIT(0)
+#define SUN6I_WATCHDOG1_CONFIG_REG      0x14
+#define SUN6I_WATCHDOG1_CONFIG_RESTART          BIT(0)
+#define SUN6I_WATCHDOG1_CONFIG_IRQ              BIT(1)
+#define SUN6I_WATCHDOG1_MODE_REG        0x18
+#define SUN6I_WATCHDOG1_MODE_ENABLE             BIT(0)
+
+static void __iomem *wdt_base;
+
+static void sun6i_wdt_restart(enum reboot_mode mode, const char *cmd)
+{
+        if (!wdt_base)
+                return;
+
+        /* Disable interrupts */
+        writel(0, wdt_base + SUN6I_WATCHDOG1_IRQ_REG);
+
+        /* We want to disable the IRQ and just reset the whole system */
+        writel(SUN6I_WATCHDOG1_CONFIG_RESTART,
+                wdt_base + SUN6I_WATCHDOG1_CONFIG_REG);
+
+        /* Enable timer. The default and lowest interval value is 0.5s */
+        writel(SUN6I_WATCHDOG1_MODE_ENABLE,
+                wdt_base + SUN6I_WATCHDOG1_MODE_REG);
+
+        /* Restart the watchdog. */
+        writel(SUN6I_WATCHDOG1_CTRL_RESTART,
+                wdt_base + SUN6I_WATCHDOG1_CTRL_REG);
+
+        while (1) {
+                mdelay(5);
+                writel(SUN6I_WATCHDOG1_MODE_ENABLE,
+                        wdt_base + SUN6I_WATCHDOG1_MODE_REG);
+        }
+}
+
+static int sun6i_reboot_probe(struct platform_device *pdev)
+{
+        wdt_base = of_iomap(pdev->dev.of_node, 0);
+        if (!wdt_base) {
+                WARN(1, "failed to map watchdog base address");
+                return -ENODEV;
+        }
+
+        arm_pm_restart = sun6i_wdt_restart;
+
+        return 0;
+}
+
+static struct of_device_id sun6i_reboot_of_match[] = {
+        { .compatible = "allwinner,sun6i-a31-wdt" },
+        {}
+};
+
+static struct platform_driver sun6i_reboot_driver = {
+        .probe = sun6i_reboot_probe,
+        .driver = {
+                .name = "sun6i-reboot",
+                .of_match_table = sun6i_reboot_of_match,
+        },
+};
+module_platform_driver(sun6i_reboot_driver);