reset.c

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/*
 * 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.
 *
 * Copyright (C) 2012 Thomas Langer <[email protected]>
 * Copyright (C) 2012 John Crispin <[email protected]>
 */

#include <linux/init.h>
#include <linux/io.h>
#include <linux/pm.h>
#include <asm/reboot.h>
#include <linux/export.h>

#include <lantiq_soc.h>

/* CPU0 Reset Source Register */
#define SYS1_CPU0RS     0x0040
/* reset cause mask */
#define CPU0RS_MASK     0x0003
/* CPU0 Boot Mode Register */
#define SYS1_BM         0x00a0
/* boot mode mask */
#define BM_MASK         0x0005

/* allow platform code to find out what surce we booted from */
unsigned char ltq_boot_select(void)
{
    return ltq_sys1_r32(SYS1_BM) & BM_MASK;
}

/* allow the watchdog driver to find out what the boot reason was */
int ltq_reset_cause(void)
{
    return ltq_sys1_r32(SYS1_CPU0RS) & CPU0RS_MASK;
}
EXPORT_SYMBOL_GPL(ltq_reset_cause);

#define BOOT_REG_BASE   (KSEG1 | 0x1F200000)
#define BOOT_PW1_REG    (BOOT_REG_BASE | 0x20)
#define BOOT_PW2_REG    (BOOT_REG_BASE | 0x24)
#define BOOT_PW1    0x4C545100
#define BOOT_PW2    0x0051544C

#define WDT_REG_BASE    (KSEG1 | 0x1F8803F0)
#define WDT_PW1     0x00BE0000
#define WDT_PW2     0x00DC0000

static void machine_restart(char *command)
{
    local_irq_disable();

    /* reboot magic */
    ltq_w32(BOOT_PW1, (void *)BOOT_PW1_REG); /* 'LTQ\0' */
    ltq_w32(BOOT_PW2, (void *)BOOT_PW2_REG); /* '\0QTL' */
    ltq_w32(0, (void *)BOOT_REG_BASE); /* reset Bootreg RVEC */

    /* watchdog magic */
    ltq_w32(WDT_PW1, (void *)WDT_REG_BASE);
    ltq_w32(WDT_PW2 |
        (0x3 << 26) | /* PWL */
        (0x2 << 24) | /* CLKDIV */
        (0x1 << 31) | /* enable */
        (1), /* reload */
        (void *)WDT_REG_BASE);
    unreachable();
}

static void machine_halt(void)
{
    local_irq_disable();
    unreachable();
}

static void machine_power_off(void)
{
    local_irq_disable();
    unreachable();
}

static int __init mips_reboot_setup(void)
{
    _machine_restart = machine_restart;
    _machine_halt = machine_halt;
    pm_power_off = machine_power_off;
    return 0;
}

arch_initcall(mips_reboot_setup);