LXR linux/arch/arm/mach-pxa/pm.c

   1/*
   2 * PXA250/210 Power Management Routines
   3 *
   4 * Original code for the SA11x0:
   5 * Copyright (c) 2001 Cliff Brake <cbrake@accelent.com>
   6 *
   7 * Modified for the PXA250 by Nicolas Pitre:
   8 * Copyright (c) 2002 Monta Vista Software, Inc.
   9 *
  10 * This program is free software; you can redistribute it and/or
  11 * modify it under the terms of the GNU General Public License.
  12 */
  13#include <linux/init.h>
  14#include <linux/module.h>
  15#include <linux/suspend.h>
  16#include <linux/errno.h>
  17#include <linux/time.h>
  18
  19#include <asm/hardware.h>
  20#include <asm/memory.h>
  21#include <asm/system.h>
  22#include <asm/arch/pm.h>
  23#include <asm/arch/pxa-regs.h>
  24#include <asm/arch/lubbock.h>
  25#include <asm/mach/time.h>
  26
  27struct pxa_cpu_pm_fns *pxa_cpu_pm_fns;
  28static unsigned long *sleep_save;
  29
  30int pxa_pm_enter(suspend_state_t state)
  31{
  32        unsigned long sleep_save_checksum = 0, checksum = 0;
  33        int i;
  34
  35#ifdef CONFIG_IWMMXT
  36        /* force any iWMMXt context to ram **/
  37        if (elf_hwcap & HWCAP_IWMMXT)
  38                iwmmxt_task_disable(NULL);
  39#endif
  40
  41        pxa_cpu_pm_fns->save(sleep_save);
  42
  43        /* Clear sleep reset status */
  44        RCSR = RCSR_SMR;
  45
  46        /* before sleeping, calculate and save a checksum */
  47        for (i = 0; i < pxa_cpu_pm_fns->save_size - 1; i++)
  48                sleep_save_checksum += sleep_save[i];
  49
  50        /* *** go zzz *** */
  51        pxa_cpu_pm_fns->enter(state);
  52        cpu_init();
  53
  54        /* after sleeping, validate the checksum */
  55        for (i = 0; i < pxa_cpu_pm_fns->save_size - 1; i++)
  56                checksum += sleep_save[i];
  57
  58        /* if invalid, display message and wait for a hardware reset */
  59        if (checksum != sleep_save_checksum) {
  60#ifdef CONFIG_ARCH_LUBBOCK
  61                LUB_HEXLED = 0xbadbadc5;
  62#endif
  63                while (1)
  64                        pxa_cpu_pm_fns->enter(state);
  65        }
  66
  67        pxa_cpu_pm_fns->restore(sleep_save);
  68
  69        pr_debug("*** made it back from resume\n");
  70
  71        return 0;
  72}
  73
  74EXPORT_SYMBOL_GPL(pxa_pm_enter);
  75
  76unsigned long sleep_phys_sp(void *sp)
  77{
  78        return virt_to_phys(sp);
  79}
  80
  81static int pxa_pm_valid(suspend_state_t state)
  82{
  83        if (pxa_cpu_pm_fns)
  84                return pxa_cpu_pm_fns->valid(state);
  85
  86        return -EINVAL;
  87}
  88
  89static struct platform_suspend_ops pxa_pm_ops = {
  90        .valid          = pxa_pm_valid,
  91        .enter          = pxa_pm_enter,
  92};
  93
  94static int __init pxa_pm_init(void)
  95{
  96        if (!pxa_cpu_pm_fns) {
  97                printk(KERN_ERR "no valid pxa_cpu_pm_fns defined\n");
  98                return -EINVAL;
  99        }
 100
 101        sleep_save = kmalloc(pxa_cpu_pm_fns->save_size, GFP_KERNEL);
 102        if (!sleep_save) {
 103                printk(KERN_ERR "failed to alloc memory for pm save\n");
 104                return -ENOMEM;
 105        }
 106
 107        suspend_set_ops(&pxa_pm_ops);
 108        return 0;
 109}
 110
 111device_initcall(pxa_pm_init);
 112