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
  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         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
  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 struct pm_ops pxa_pm_ops = {
  90         .valid          = pxa_pm_valid,
  91         .enter          = pxa_pm_enter,
  92 };
  93
  94 static 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         pm_set_ops(&pxa_pm_ops);
 108         return 0;
 109 }
 110
 111 device_initcall(pxa_pm_init);