pm.c

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/*
 * linux/arch/unicore32/kernel/pm.c
 *
 * Code specific to PKUnity SoC and UniCore ISA
 *
 *  Maintained by GUAN Xue-tao <[email protected]>
 *  Copyright (C) 2001-2010 Guan Xuetao
 *
 * 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/init.h>
#include <linux/module.h>
#include <linux/suspend.h>
#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/io.h>

#include <mach/hardware.h>
#include <mach/pm.h>

#include "setup.h"

struct puv3_cpu_pm_fns *puv3_cpu_pm_fns;
static unsigned long *sleep_save;

int puv3_pm_enter(suspend_state_t state)
{
    unsigned long sleep_save_checksum = 0, checksum = 0;
    int i;

    /* skip registers saving for standby */
    if (state != PM_SUSPEND_STANDBY) {
        puv3_cpu_pm_fns->save(sleep_save);
        /* before sleeping, calculate and save a checksum */
        for (i = 0; i < puv3_cpu_pm_fns->save_count - 1; i++)
            sleep_save_checksum += sleep_save[i];
    }

    /* *** go zzz *** */
    puv3_cpu_pm_fns->enter(state);
    cpu_init();
#ifdef CONFIG_INPUT_KEYBOARD
    puv3_ps2_init();
#endif
#ifdef CONFIG_PCI
    pci_puv3_preinit();
#endif
    if (state != PM_SUSPEND_STANDBY) {
        /* after sleeping, validate the checksum */
        for (i = 0; i < puv3_cpu_pm_fns->save_count - 1; i++)
            checksum += sleep_save[i];

        /* if invalid, display message and wait for a hardware reset */
        if (checksum != sleep_save_checksum) {
            while (1)
                puv3_cpu_pm_fns->enter(state);
        }
        puv3_cpu_pm_fns->restore(sleep_save);
    }

    pr_debug("*** made it back from resume\n");

    return 0;
}
EXPORT_SYMBOL_GPL(puv3_pm_enter);

unsigned long sleep_phys_sp(void *sp)
{
    return virt_to_phys(sp);
}

static int puv3_pm_valid(suspend_state_t state)
{
    if (puv3_cpu_pm_fns)
        return puv3_cpu_pm_fns->valid(state);

    return -EINVAL;
}

static int puv3_pm_prepare(void)
{
    int ret = 0;

    if (puv3_cpu_pm_fns && puv3_cpu_pm_fns->prepare)
        ret = puv3_cpu_pm_fns->prepare();

    return ret;
}

static void puv3_pm_finish(void)
{
    if (puv3_cpu_pm_fns && puv3_cpu_pm_fns->finish)
        puv3_cpu_pm_fns->finish();
}

static struct platform_suspend_ops puv3_pm_ops = {
    .valid      = puv3_pm_valid,
    .enter      = puv3_pm_enter,
    .prepare    = puv3_pm_prepare,
    .finish     = puv3_pm_finish,
};

static int __init puv3_pm_init(void)
{
    if (!puv3_cpu_pm_fns) {
        printk(KERN_ERR "no valid puv3_cpu_pm_fns defined\n");
        return -EINVAL;
    }

    sleep_save = kmalloc(puv3_cpu_pm_fns->save_count
                * sizeof(unsigned long), GFP_KERNEL);
    if (!sleep_save) {
        printk(KERN_ERR "failed to alloc memory for pm save\n");
        return -ENOMEM;
    }

    suspend_set_ops(&puv3_pm_ops);
    return 0;
}

device_initcall(puv3_pm_init);