LXR linux/arch/mips/lantiq/xway/reset.c

   1/*
   2 *  This program is free software; you can redistribute it and/or modify it
   3 *  under the terms of the GNU General Public License version 2 as published
   4 *  by the Free Software Foundation.
   5 *
   6 *  Copyright (C) 2010 John Crispin <blogic@openwrt.org>
   7 */
   8
   9#include <linux/init.h>
  10#include <linux/io.h>
  11#include <linux/ioport.h>
  12#include <linux/pm.h>
  13#include <linux/export.h>
  14#include <asm/reboot.h>
  15
  16#include <lantiq_soc.h>
  17
  18#define ltq_rcu_w32(x, y)       ltq_w32((x), ltq_rcu_membase + (y))
  19#define ltq_rcu_r32(x)          ltq_r32(ltq_rcu_membase + (x))
  20
  21/* register definitions */
  22#define LTQ_RCU_RST             0x0010
  23#define LTQ_RCU_RST_ALL         0x40000000
  24
  25#define LTQ_RCU_RST_STAT        0x0014
  26#define LTQ_RCU_STAT_SHIFT      26
  27
  28static struct resource ltq_rcu_resource = {
  29        .name   = "rcu",
  30        .start  = LTQ_RCU_BASE_ADDR,
  31        .end    = LTQ_RCU_BASE_ADDR + LTQ_RCU_SIZE - 1,
  32        .flags  = IORESOURCE_MEM,
  33};
  34
  35/* remapped base addr of the reset control unit */
  36static void __iomem *ltq_rcu_membase;
  37
  38/* This function is used by the watchdog driver */
  39int ltq_reset_cause(void)
  40{
  41        u32 val = ltq_rcu_r32(LTQ_RCU_RST_STAT);
  42        return val >> LTQ_RCU_STAT_SHIFT;
  43}
  44EXPORT_SYMBOL_GPL(ltq_reset_cause);
  45
  46static void ltq_machine_restart(char *command)
  47{
  48        pr_notice("System restart\n");
  49        local_irq_disable();
  50        ltq_rcu_w32(ltq_rcu_r32(LTQ_RCU_RST) | LTQ_RCU_RST_ALL, LTQ_RCU_RST);
  51        unreachable();
  52}
  53
  54static void ltq_machine_halt(void)
  55{
  56        pr_notice("System halted.\n");
  57        local_irq_disable();
  58        unreachable();
  59}
  60
  61static void ltq_machine_power_off(void)
  62{
  63        pr_notice("Please turn off the power now.\n");
  64        local_irq_disable();
  65        unreachable();
  66}
  67
  68static int __init mips_reboot_setup(void)
  69{
  70        /* insert and request the memory region */
  71        if (insert_resource(&iomem_resource, &ltq_rcu_resource) < 0)
  72                panic("Failed to insert rcu memory\n");
  73
  74        if (request_mem_region(ltq_rcu_resource.start,
  75                        resource_size(&ltq_rcu_resource), "rcu") < 0)
  76                panic("Failed to request rcu memory\n");
  77
  78        /* remap rcu register range */
  79        ltq_rcu_membase = ioremap_nocache(ltq_rcu_resource.start,
  80                                resource_size(&ltq_rcu_resource));
  81        if (!ltq_rcu_membase)
  82                panic("Failed to remap rcu memory\n");
  83
  84        _machine_restart = ltq_machine_restart;
  85        _machine_halt = ltq_machine_halt;
  86        pm_power_off = ltq_machine_power_off;
  87
  88        return 0;
  89}
  90
  91arch_initcall(mips_reboot_setup);
  92