cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
Log | Files | Refs | README | LICENSE | sfeed.txt

pm.c (2591B)

      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
     21struct pxa_cpu_pm_fns *pxa_cpu_pm_fns;
     22static unsigned long *sleep_save;
     23
     24int 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			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
     67EXPORT_SYMBOL_GPL(pxa_pm_enter);
     68
     69static int pxa_pm_valid(suspend_state_t state)
     70{
     71	if (pxa_cpu_pm_fns)
     72		return pxa_cpu_pm_fns->valid(state);
     73
     74	return -EINVAL;
     75}
     76
     77int pxa_pm_prepare(void)
     78{
     79	int ret = 0;
     80
     81	if (pxa_cpu_pm_fns && pxa_cpu_pm_fns->prepare)
     82		ret = pxa_cpu_pm_fns->prepare();
     83
     84	return ret;
     85}
     86
     87void pxa_pm_finish(void)
     88{
     89	if (pxa_cpu_pm_fns && pxa_cpu_pm_fns->finish)
     90		pxa_cpu_pm_fns->finish();
     91}
     92
     93static const struct platform_suspend_ops pxa_pm_ops = {
     94	.valid		= pxa_pm_valid,
     95	.enter		= pxa_pm_enter,
     96	.prepare	= pxa_pm_prepare,
     97	.finish		= pxa_pm_finish,
     98};
     99
    100static int __init pxa_pm_init(void)
    101{
    102	if (!pxa_cpu_pm_fns) {
    103		printk(KERN_ERR "no valid pxa_cpu_pm_fns defined\n");
    104		return -EINVAL;
    105	}
    106
    107	sleep_save = kmalloc_array(pxa_cpu_pm_fns->save_count,
    108				   sizeof(*sleep_save),
    109				   GFP_KERNEL);
    110	if (!sleep_save)
    111		return -ENOMEM;
    112
    113	suspend_set_ops(&pxa_pm_ops);
    114	return 0;
    115}
    116
    117device_initcall(pxa_pm_init);