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

   1/*
   2 * Hisilicon SoC reset code
   3 *
   4 * Copyright (c) 2014 Hisilicon Ltd.
   5 * Copyright (c) 2014 Linaro Ltd.
   6 *
   7 * Author: Haojian Zhuang <haojian.zhuang@linaro.org>
   8 *
   9 * This program is free software; you can redistribute it and/or modify
  10 * it under the terms of the GNU General Public License version 2 as
  11 * published by the Free Software Foundation.
  12 */
  13
  14#include <linux/delay.h>
  15#include <linux/io.h>
  16#include <linux/module.h>
  17#include <linux/of_address.h>
  18#include <linux/platform_device.h>
  19#include <linux/reboot.h>
  20
  21#include <asm/proc-fns.h>
  22#include <asm/system_misc.h>
  23
  24static void __iomem *base;
  25static u32 reboot_offset;
  26
  27static void hisi_restart(enum reboot_mode mode, const char *cmd)
  28{
  29        writel_relaxed(0xdeadbeef, base + reboot_offset);
  30
  31        while (1)
  32                cpu_do_idle();
  33}
  34
  35static int hisi_reboot_probe(struct platform_device *pdev)
  36{
  37        struct device_node *np = pdev->dev.of_node;
  38
  39        base = of_iomap(np, 0);
  40        if (!base) {
  41                WARN(1, "failed to map base address");
  42                return -ENODEV;
  43        }
  44
  45        if (of_property_read_u32(np, "reboot-offset", &reboot_offset) < 0) {
  46                pr_err("failed to find reboot-offset property\n");
  47                return -EINVAL;
  48        }
  49
  50        arm_pm_restart = hisi_restart;
  51
  52        return 0;
  53}
  54
  55static struct of_device_id hisi_reboot_of_match[] = {
  56        { .compatible = "hisilicon,sysctrl" },
  57        {}
  58};
  59
  60static struct platform_driver hisi_reboot_driver = {
  61        .probe = hisi_reboot_probe,
  62        .driver = {
  63                .name = "hisi-reboot",
  64                .of_match_table = hisi_reboot_of_match,
  65        },
  66};
  67module_platform_driver(hisi_reboot_driver);
  68