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 <mach/hardware.h>
  20 #include <asm/memory.h>
  21 #include <asm/system.h>
  22 #include <mach/pm.h>
  23 #include <mach/pxa-regs.h>
  24 #include <mach/lubbock.h>
  25 #include <asm/mach/time.h>
  26
  27 struct pxa_cpu_pm_fns *pxa_cpu_pm_fns;
  28 static unsigned long *sleep_save;
  29
  30 int 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         /* skip registers saving for standby */
  42         if (state != PM_SUSPEND_STANDBY) {
  43                 pxa_cpu_pm_fns->save(sleep_save);
  44                 /* before sleeping, calculate and save a checksum */
  45                 for (i = 0; i < pxa_cpu_pm_fns->save_count - 1; i++)
  46                         sleep_save_checksum += sleep_save[i];
  47         }
  48
  49         /* *** go zzz *** */
  50         pxa_cpu_pm_fns->enter(state);
  51         cpu_init();
  52
  53         if (state != PM_SUSPEND_STANDBY) {
  54                 /* after sleeping, validate the checksum */
  55                 for (i = 0; i < pxa_cpu_pm_fns->save_count - 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                 pxa_cpu_pm_fns->restore(sleep_save);
  67         }
  68
  69         pr_debug("*** made it back from resume\n");
  70
  71         return 0;
  72 }
  73
  74 EXPORT_SYMBOL_GPL(pxa_pm_enter);
  75
  76 unsigned long sleep_phys_sp(void *sp)
  77 {
  78         return virt_to_phys(sp);
  79 }
  80
  81 static 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
  89 static int pxa_pm_prepare(void)
  90 {
  91         int ret = 0;
  92
  93         if (pxa_cpu_pm_fns && pxa_cpu_pm_fns->prepare)
  94                 ret = pxa_cpu_pm_fns->prepare();
  95
  96         return ret;
  97 }
  98
  99 static void pxa_pm_finish(void)
 100 {
 101         if (pxa_cpu_pm_fns && pxa_cpu_pm_fns->finish)
 102                 pxa_cpu_pm_fns->finish();
 103 }
 104
 105 static struct platform_suspend_ops pxa_pm_ops = {
 106         .valid          = pxa_pm_valid,
 107         .enter          = pxa_pm_enter,
 108         .prepare        = pxa_pm_prepare,
 109         .finish         = pxa_pm_finish,
 110 };
 111
 112 static int __init pxa_pm_init(void)
 113 {
 114         if (!pxa_cpu_pm_fns) {
 115                 printk(KERN_ERR "no valid pxa_cpu_pm_fns defined\n");
 116                 return -EINVAL;
 117         }
 118
 119         sleep_save = kmalloc(pxa_cpu_pm_fns->save_count * sizeof(unsigned long),
 120                              GFP_KERNEL);
 121         if (!sleep_save) {
 122                 printk(KERN_ERR "failed to alloc memory for pm save\n");
 123                 return -ENOMEM;
 124         }
 125
 126         suspend_set_ops(&pxa_pm_ops);
 127         return 0;
 128 }
 129
 130 device_initcall(pxa_pm_init);