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/slab.h> 18 19 #include "pm.h" 20 21 struct pxa_cpu_pm_fns *pxa_cpu_pm_fns; 22 static unsigned long *sleep_save; 23 24 int pxa_pm_enter(suspend_state_t state) 25 { 26 unsigned long sleep_save_checksum = 0, checksum = 0; 27 int i; 28 29 #ifdef CONFIG_IWMMXT 30 /* force any iWMMXt context to ram **/ 31 if (elf_hwcap & HWCAP_IWMMXT) 32 iwmmxt_task_disable(NULL); 33 #endif 34 35 /* skip registers saving for standby */ 36 if (state != PM_SUSPEND_STANDBY && pxa_cpu_pm_fns->save) { 37 pxa_cpu_pm_fns->save(sleep_save); 38 /* before sleeping, calculate and save a checksum */ 39 for (i = 0; i < pxa_cpu_pm_fns->save_count - 1; i++) 40 sleep_save_checksum += sleep_save[i]; 41 } 42 43 /* *** go zzz *** */ 44 pxa_cpu_pm_fns->enter(state); 45 46 if (state != PM_SUSPEND_STANDBY && pxa_cpu_pm_fns->restore) { 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 while (1) 55 pxa_cpu_pm_fns->enter(state); 56 } 57 pxa_cpu_pm_fns->restore(sleep_save); 58 } 59 60 pr_debug("*** made it back from resume\n"); 61 62 return 0; 63 } 64 65 EXPORT_SYMBOL_GPL(pxa_pm_enter); 66 67 static int pxa_pm_valid(suspend_state_t state) 68 { 69 if (pxa_cpu_pm_fns) 70 return pxa_cpu_pm_fns->valid(state); 71 72 return -EINVAL; 73 } 74 75 int pxa_pm_prepare(void) 76 { 77 int ret = 0; 78 79 if (pxa_cpu_pm_fns && pxa_cpu_pm_fns->prepare) 80 ret = pxa_cpu_pm_fns->prepare(); 81 82 return ret; 83 } 84 85 void pxa_pm_finish(void) 86 { 87 if (pxa_cpu_pm_fns && pxa_cpu_pm_fns->finish) 88 pxa_cpu_pm_fns->finish(); 89 } 90 91 static const struct platform_suspend_ops pxa_pm_ops = { 92 .valid = pxa_pm_valid, 93 .enter = pxa_pm_enter, 94 .prepare = pxa_pm_prepare, 95 .finish = pxa_pm_finish, 96 }; 97 98 static int __init pxa_pm_init(void) 99 { 100 if (!pxa_cpu_pm_fns) { 101 printk(KERN_ERR "no valid pxa_cpu_pm_fns defined\n"); 102 return -EINVAL; 103 } 104 105 sleep_save = kmalloc_array(pxa_cpu_pm_fns->save_count, 106 sizeof(*sleep_save), 107 GFP_KERNEL); 108 if (!sleep_save) 109 return -ENOMEM; 110 111 suspend_set_ops(&pxa_pm_ops); 112 return 0; 113 } 114 115 device_initcall(pxa_pm_init); 116