linux/drivers/power/reset/hisi-reboot.c

83 lines
1.8 KiB
C

/*
* Hisilicon SoC reset code
*
* Copyright (c) 2014 Hisilicon Ltd.
* Copyright (c) 2014 Linaro Ltd.
*
* Author: Haojian Zhuang <haojian.zhuang@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 u32 reboot_offset;
static int hisi_restart_handler(struct notifier_block *this,
unsigned long mode, void *cmd)
{
writel_relaxed(0xdeadbeef, base + reboot_offset);
while (1)
cpu_do_idle();
return NOTIFY_DONE;
}
static struct notifier_block hisi_restart_nb = {
.notifier_call = hisi_restart_handler,
.priority = 128,
};
static int hisi_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;
}
if (of_property_read_u32(np, "reboot-offset", &reboot_offset) < 0) {
pr_err("failed to find reboot-offset property\n");
iounmap(base);
return -EINVAL;
}
err = register_restart_handler(&hisi_restart_nb);
if (err) {
dev_err(&pdev->dev, "cannot register restart handler (err=%d)\n",
err);
iounmap(base);
}
return err;
}
static const struct of_device_id hisi_reboot_of_match[] = {
{ .compatible = "hisilicon,sysctrl" },
{}
};
static struct platform_driver hisi_reboot_driver = {
.probe = hisi_reboot_probe,
.driver = {
.name = "hisi-reboot",
.of_match_table = hisi_reboot_of_match,
},
};
module_platform_driver(hisi_reboot_driver);