power/reset: zx: Register restart handler

Register with kernel restart handler instead of setting arm_pm_restart
directly.

Signed-off-by: Jun Nie <jun.nie@linaro.org>
Signed-off-by: Sebastian Reichel <sre@kernel.org>

drivers/power/reset/Kconfig

@@ -166,5 +166,12 @@ config POWER_RESET_RMOBILE
 	help
 	  Reboot support for Renesas R-Mobile and SH-Mobile SoCs.
 
+config POWER_RESET_ZX
+	tristate "ZTE SoCs reset driver"
+	depends on ARCH_ZX || COMPILE_TEST
+	depends on HAS_IOMEM
+	help
+	  Reboot support for ZTE SoCs.
+
 endif
 

drivers/power/reset/Makefile

@@ -19,3 +19,4 @@ obj-$(CONFIG_POWER_RESET_KEYSTONE) += keystone-reset.o
 obj-$(CONFIG_POWER_RESET_SYSCON) += syscon-reboot.o
 obj-$(CONFIG_POWER_RESET_SYSCON_POWEROFF) += syscon-poweroff.o
 obj-$(CONFIG_POWER_RESET_RMOBILE) += rmobile-reset.o
+obj-$(CONFIG_POWER_RESET_ZX) += zx-reboot.o

drivers/power/reset/zx-reboot.c

@@ -0,0 +1,82 @@
+/*
+ * ZTE zx296702 SoC reset code
+ *
+ * Copyright (c) 2015 Linaro Ltd.
+ *
+ * Author: Jun Nie <jun.nie@linaro.org>
+ *
+ * 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.
+ */
+
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/notifier.h>
+#include <linux/of_address.h>
+#include <linux/platform_device.h>
+#include <linux/reboot.h>
+
+#include <asm/proc-fns.h>
+
+static void __iomem *base;
+static void __iomem *pcu_base;
+
+static int zx_restart_handler(struct notifier_block *this,
+			      unsigned long mode, void *cmd)
+{
+	writel_relaxed(1, base + 0xb0);
+	writel_relaxed(1, pcu_base + 0x34);
+
+	mdelay(50);
+	pr_emerg("Unable to restart system\n");
+
+	return NOTIFY_DONE;
+}
+
+static struct notifier_block zx_restart_nb = {
+	.notifier_call = zx_restart_handler,
+	.priority = 128,
+};
+
+static int zx_reboot_probe(struct platform_device *pdev)
+{
+	struct device_node *np = pdev->dev.of_node;
+	int err;
+
+	base = of_iomap(np, 0);
+	if (!base) {
+		WARN(1, "failed to map base address");
+		return -ENODEV;
+	}
+
+	np = of_find_compatible_node(NULL, NULL, "zte,zx296702-pcu");
+	pcu_base = of_iomap(np, 0);
+	if (!pcu_base) {
+		iounmap(base);
+		WARN(1, "failed to map pcu_base address");
+		return -ENODEV;
+	}
+
+	err = register_restart_handler(&zx_restart_nb);
+	if (err)
+		dev_err(&pdev->dev, "Register restart handler failed(err=%d)\n",
+			err);
+
+	return err;
+}
+
+static const struct of_device_id zx_reboot_of_match[] = {
+	{ .compatible = "zte,sysctrl" },
+	{}
+};
+
+static struct platform_driver zx_reboot_driver = {
+	.probe = zx_reboot_probe,
+	.driver = {
+		.name = "zx-reboot",
+		.of_match_table = zx_reboot_of_match,
+	},
+};
+module_platform_driver(zx_reboot_driver);