tegrakernel/kernel/kernel-4.9/arch/arm/mach-pxa/pm.c

120 lines
2.6 KiB
C

/*
* PXA250/210 Power Management Routines
*
* Original code for the SA11x0:
* Copyright (c) 2001 Cliff Brake <cbrake@accelent.com>
*
* Modified for the PXA250 by Nicolas Pitre:
* Copyright (c) 2002 Monta Vista Software, Inc.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License.
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/suspend.h>
#include <linux/errno.h>
#include <linux/slab.h>
#include "pm.h"
struct pxa_cpu_pm_fns *pxa_cpu_pm_fns;
static unsigned long *sleep_save;
int pxa_pm_enter(suspend_state_t state)
{
unsigned long sleep_save_checksum = 0, checksum = 0;
int i;
#ifdef CONFIG_IWMMXT
/* force any iWMMXt context to ram **/
if (elf_hwcap & HWCAP_IWMMXT)
iwmmxt_task_disable(NULL);
#endif
/* skip registers saving for standby */
if (state != PM_SUSPEND_STANDBY && pxa_cpu_pm_fns->save) {
pxa_cpu_pm_fns->save(sleep_save);
/* before sleeping, calculate and save a checksum */
for (i = 0; i < pxa_cpu_pm_fns->save_count - 1; i++)
sleep_save_checksum += sleep_save[i];
}
/* *** go zzz *** */
pxa_cpu_pm_fns->enter(state);
if (state != PM_SUSPEND_STANDBY && pxa_cpu_pm_fns->restore) {
/* after sleeping, validate the checksum */
for (i = 0; i < pxa_cpu_pm_fns->save_count - 1; i++)
checksum += sleep_save[i];
/* if invalid, display message and wait for a hardware reset */
if (checksum != sleep_save_checksum) {
lubbock_set_hexled(0xbadbadc5);
while (1)
pxa_cpu_pm_fns->enter(state);
}
pxa_cpu_pm_fns->restore(sleep_save);
}
pr_debug("*** made it back from resume\n");
return 0;
}
EXPORT_SYMBOL_GPL(pxa_pm_enter);
static int pxa_pm_valid(suspend_state_t state)
{
if (pxa_cpu_pm_fns)
return pxa_cpu_pm_fns->valid(state);
return -EINVAL;
}
int pxa_pm_prepare(void)
{
int ret = 0;
if (pxa_cpu_pm_fns && pxa_cpu_pm_fns->prepare)
ret = pxa_cpu_pm_fns->prepare();
return ret;
}
void pxa_pm_finish(void)
{
if (pxa_cpu_pm_fns && pxa_cpu_pm_fns->finish)
pxa_cpu_pm_fns->finish();
}
static const struct platform_suspend_ops pxa_pm_ops = {
.valid = pxa_pm_valid,
.enter = pxa_pm_enter,
.prepare = pxa_pm_prepare,
.finish = pxa_pm_finish,
};
static int __init pxa_pm_init(void)
{
if (!pxa_cpu_pm_fns) {
printk(KERN_ERR "no valid pxa_cpu_pm_fns defined\n");
return -EINVAL;
}
sleep_save = kmalloc_array(pxa_cpu_pm_fns->save_count,
sizeof(*sleep_save),
GFP_KERNEL);
if (!sleep_save) {
printk(KERN_ERR "failed to alloc memory for pm save\n");
return -ENOMEM;
}
suspend_set_ops(&pxa_pm_ops);
return 0;
}
device_initcall(pxa_pm_init);