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
  18 #include <mach/pm.h>
  19
  20 struct pxa_cpu_pm_fns *pxa_cpu_pm_fns;
  21 static unsigned long *sleep_save;
  22
  23 int pxa_pm_enter(suspend_state_t state)
  24 {
  25         unsigned long sleep_save_checksum = 0, checksum = 0;
  26         int i;
  27
  28 #ifdef CONFIG_IWMMXT
  29         /* force any iWMMXt context to ram **/
  30         if (elf_hwcap & HWCAP_IWMMXT)
  31                 iwmmxt_task_disable(NULL);
  32 #endif
  33
  34         /* skip registers saving for standby */
  35         if (state != PM_SUSPEND_STANDBY) {
  36                 pxa_cpu_pm_fns->save(sleep_save);
  37                 /* before sleeping, calculate and save a checksum */
  38                 for (i = 0; i < pxa_cpu_pm_fns->save_count - 1; i++)
  39                         sleep_save_checksum += sleep_save[i];
  40         }
  41
  42         /* *** go zzz *** */
  43         pxa_cpu_pm_fns->enter(state);
  44         cpu_init();
  45
  46         if (state != PM_SUSPEND_STANDBY) {
  47                 /* after sleeping, validate the checksum */
  48                 for (i = 0; i < pxa_cpu_pm_fns->save_count - 1; i++)
  49                         checksum += sleep_save[i];
  50
  51                 /* if invalid, display message and wait for a hardware reset */
  52                 if (checksum != sleep_save_checksum) {
  53
  54                         lubbock_set_hexled(0xbadbadc5);
  55
  56                         while (1)
  57                                 pxa_cpu_pm_fns->enter(state);
  58                 }
  59                 pxa_cpu_pm_fns->restore(sleep_save);
  60         }
  61
  62         pr_debug("*** made it back from resume\n");
  63
  64         return 0;
  65 }
  66
  67 EXPORT_SYMBOL_GPL(pxa_pm_enter);
  68
  69 unsigned long sleep_phys_sp(void *sp)
  70 {
  71         return virt_to_phys(sp);
  72 }
  73
  74 static int pxa_pm_valid(suspend_state_t state)
  75 {
  76         if (pxa_cpu_pm_fns)
  77                 return pxa_cpu_pm_fns->valid(state);
  78
  79         return -EINVAL;
  80 }
  81
  82 int pxa_pm_prepare(void)
  83 {
  84         int ret = 0;
  85
  86         if (pxa_cpu_pm_fns && pxa_cpu_pm_fns->prepare)
  87                 ret = pxa_cpu_pm_fns->prepare();
  88
  89         return ret;
  90 }
  91
  92 void pxa_pm_finish(void)
  93 {
  94         if (pxa_cpu_pm_fns && pxa_cpu_pm_fns->finish)
  95                 pxa_cpu_pm_fns->finish();
  96 }
  97
  98 static struct platform_suspend_ops pxa_pm_ops = {
  99         .valid          = pxa_pm_valid,
 100         .enter          = pxa_pm_enter,
 101         .prepare        = pxa_pm_prepare,
 102         .finish         = pxa_pm_finish,
 103 };
 104
 105 static int __init pxa_pm_init(void)
 106 {
 107         if (!pxa_cpu_pm_fns) {
 108                 printk(KERN_ERR "no valid pxa_cpu_pm_fns defined\n");
 109                 return -EINVAL;
 110         }
 111
 112         sleep_save = kmalloc(pxa_cpu_pm_fns->save_count * sizeof(unsigned long),
 113                              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(&pxa_pm_ops);
 120         return 0;
 121 }
 122
 123 device_initcall(pxa_pm_init);