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         /* 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_size - 1; i++)
  46                         sleep_save_checksum += sleep_save[i];
  47         }
  48
  49         /* Clear sleep reset status */
  50         RCSR = RCSR_SMR;
  51
  52         /* *** go zzz *** */
  53         pxa_cpu_pm_fns->enter(state);
  54         cpu_init();
  55
  56         if (state != PM_SUSPEND_STANDBY) {
  57                 /* after sleeping, validate the checksum */
  58                 for (i = 0; i < pxa_cpu_pm_fns->save_size - 1; i++)
  59                         checksum += sleep_save[i];
  60
  61                 /* if invalid, display message and wait for a hardware reset */
  62                 if (checksum != sleep_save_checksum) {
  63 #ifdef CONFIG_ARCH_LUBBOCK
  64                         LUB_HEXLED = 0xbadbadc5;
  65 #endif
  66                         while (1)
  67                                 pxa_cpu_pm_fns->enter(state);
  68                 }
  69                 pxa_cpu_pm_fns->restore(sleep_save);
  70         }
  71
  72         pr_debug("*** made it back from resume\n");
  73
  74         return 0;
  75 }
  76
  77 EXPORT_SYMBOL_GPL(pxa_pm_enter);
  78
  79 unsigned long sleep_phys_sp(void *sp)
  80 {
  81         return virt_to_phys(sp);
  82 }
  83
  84 static int pxa_pm_valid(suspend_state_t state)
  85 {
  86         if (pxa_cpu_pm_fns)
  87                 return pxa_cpu_pm_fns->valid(state);
  88
  89         return -EINVAL;
  90 }
  91
  92 static struct platform_suspend_ops pxa_pm_ops = {
  93         .valid          = pxa_pm_valid,
  94         .enter          = pxa_pm_enter,
  95 };
  96
  97 static int __init pxa_pm_init(void)
  98 {
  99         if (!pxa_cpu_pm_fns) {
 100                 printk(KERN_ERR "no valid pxa_cpu_pm_fns defined\n");
 101                 return -EINVAL;
 102         }
 103
 104         sleep_save = kmalloc(pxa_cpu_pm_fns->save_size, GFP_KERNEL);
 105         if (!sleep_save) {
 106                 printk(KERN_ERR "failed to alloc memory for pm save\n");
 107                 return -ENOMEM;
 108         }
 109
 110         suspend_set_ops(&pxa_pm_ops);
 111         return 0;
 112 }
 113
 114 device_initcall(pxa_pm_init);