LXR linux/arch/unicore32/kernel/pm.c

   1/*
   2 * linux/arch/unicore32/kernel/pm.c
   3 *
   4 * Code specific to PKUnity SoC and UniCore ISA
   5 *
   6 *      Maintained by GUAN Xue-tao <gxt@mprc.pku.edu.cn>
   7 *      Copyright (C) 2001-2010 Guan Xuetao
   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#include <linux/init.h>
  14#include <linux/module.h>
  15#include <linux/suspend.h>
  16#include <linux/errno.h>
  17#include <linux/slab.h>
  18#include <linux/io.h>
  19
  20#include <mach/hardware.h>
  21#include <mach/pm.h>
  22
  23#include "setup.h"
  24
  25struct puv3_cpu_pm_fns *puv3_cpu_pm_fns;
  26static unsigned long *sleep_save;
  27
  28int puv3_pm_enter(suspend_state_t state)
  29{
  30        unsigned long sleep_save_checksum = 0, checksum = 0;
  31        int i;
  32
  33        /* skip registers saving for standby */
  34        if (state != PM_SUSPEND_STANDBY) {
  35                puv3_cpu_pm_fns->save(sleep_save);
  36                /* before sleeping, calculate and save a checksum */
  37                for (i = 0; i < puv3_cpu_pm_fns->save_count - 1; i++)
  38                        sleep_save_checksum += sleep_save[i];
  39        }
  40
  41        /* *** go zzz *** */
  42        puv3_cpu_pm_fns->enter(state);
  43        cpu_init();
  44#ifdef CONFIG_INPUT_KEYBOARD
  45        puv3_ps2_init();
  46#endif
  47#ifdef CONFIG_PCI
  48        pci_puv3_preinit();
  49#endif
  50        if (state != PM_SUSPEND_STANDBY) {
  51                /* after sleeping, validate the checksum */
  52                for (i = 0; i < puv3_cpu_pm_fns->save_count - 1; i++)
  53                        checksum += sleep_save[i];
  54
  55                /* if invalid, display message and wait for a hardware reset */
  56                if (checksum != sleep_save_checksum) {
  57                        while (1)
  58                                puv3_cpu_pm_fns->enter(state);
  59                }
  60                puv3_cpu_pm_fns->restore(sleep_save);
  61        }
  62
  63        pr_debug("*** made it back from resume\n");
  64
  65        return 0;
  66}
  67EXPORT_SYMBOL_GPL(puv3_pm_enter);
  68
  69unsigned long sleep_phys_sp(void *sp)
  70{
  71        return virt_to_phys(sp);
  72}
  73
  74static int puv3_pm_valid(suspend_state_t state)
  75{
  76        if (puv3_cpu_pm_fns)
  77                return puv3_cpu_pm_fns->valid(state);
  78
  79        return -EINVAL;
  80}
  81
  82static int puv3_pm_prepare(void)
  83{
  84        int ret = 0;
  85
  86        if (puv3_cpu_pm_fns && puv3_cpu_pm_fns->prepare)
  87                ret = puv3_cpu_pm_fns->prepare();
  88
  89        return ret;
  90}
  91
  92static void puv3_pm_finish(void)
  93{
  94        if (puv3_cpu_pm_fns && puv3_cpu_pm_fns->finish)
  95                puv3_cpu_pm_fns->finish();
  96}
  97
  98static struct platform_suspend_ops puv3_pm_ops = {
  99        .valid          = puv3_pm_valid,
 100        .enter          = puv3_pm_enter,
 101        .prepare        = puv3_pm_prepare,
 102        .finish         = puv3_pm_finish,
 103};
 104
 105static int __init puv3_pm_init(void)
 106{
 107        if (!puv3_cpu_pm_fns) {
 108                printk(KERN_ERR "no valid puv3_cpu_pm_fns defined\n");
 109                return -EINVAL;
 110        }
 111
 112        sleep_save = kmalloc(puv3_cpu_pm_fns->save_count
 113                                * sizeof(unsigned long), GFP_KERNEL);
 114        if (!sleep_save) {
 115                printk(KERN_ERR "failed to alloc memory for pm save\n");
 116                return -ENOMEM;
 117        }
 118
 119        suspend_set_ops(&puv3_pm_ops);
 120        return 0;
 121}
 122
 123device_initcall(puv3_pm_init);
 124