forked from Qortal/Brooklyn
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
95 lines
2.0 KiB
95 lines
2.0 KiB
// SPDX-License-Identifier: GPL-2.0-or-later |
|
/* |
|
* Copyright (C) 2014 Imagination Technologies Ltd. |
|
* |
|
* CPU PM notifiers for saving/restoring general CPU state. |
|
*/ |
|
|
|
#include <linux/cpu_pm.h> |
|
#include <linux/init.h> |
|
|
|
#include <asm/dsp.h> |
|
#include <asm/fpu.h> |
|
#include <asm/mmu_context.h> |
|
#include <asm/pm.h> |
|
#include <asm/watch.h> |
|
|
|
/* Used by PM helper macros in asm/pm.h */ |
|
struct mips_static_suspend_state mips_static_suspend_state; |
|
|
|
/** |
|
* mips_cpu_save() - Save general CPU state. |
|
* Ensures that general CPU context is saved, notably FPU and DSP. |
|
*/ |
|
static int mips_cpu_save(void) |
|
{ |
|
/* Save FPU state */ |
|
lose_fpu(1); |
|
|
|
/* Save DSP state */ |
|
save_dsp(current); |
|
|
|
return 0; |
|
} |
|
|
|
/** |
|
* mips_cpu_restore() - Restore general CPU state. |
|
* Restores important CPU context. |
|
*/ |
|
static void mips_cpu_restore(void) |
|
{ |
|
unsigned int cpu = smp_processor_id(); |
|
|
|
/* Restore ASID */ |
|
if (current->mm) |
|
write_c0_entryhi(cpu_asid(cpu, current->mm)); |
|
|
|
/* Restore DSP state */ |
|
restore_dsp(current); |
|
|
|
/* Restore UserLocal */ |
|
if (cpu_has_userlocal) |
|
write_c0_userlocal(current_thread_info()->tp_value); |
|
|
|
/* Restore watch registers */ |
|
__restore_watch(current); |
|
} |
|
|
|
/** |
|
* mips_pm_notifier() - Notifier for preserving general CPU context. |
|
* @self: Notifier block. |
|
* @cmd: CPU PM event. |
|
* @v: Private data (unused). |
|
* |
|
* This is called when a CPU power management event occurs, and is used to |
|
* ensure that important CPU context is preserved across a CPU power down. |
|
*/ |
|
static int mips_pm_notifier(struct notifier_block *self, unsigned long cmd, |
|
void *v) |
|
{ |
|
int ret; |
|
|
|
switch (cmd) { |
|
case CPU_PM_ENTER: |
|
ret = mips_cpu_save(); |
|
if (ret) |
|
return NOTIFY_STOP; |
|
break; |
|
case CPU_PM_ENTER_FAILED: |
|
case CPU_PM_EXIT: |
|
mips_cpu_restore(); |
|
break; |
|
} |
|
|
|
return NOTIFY_OK; |
|
} |
|
|
|
static struct notifier_block mips_pm_notifier_block = { |
|
.notifier_call = mips_pm_notifier, |
|
}; |
|
|
|
static int __init mips_pm_init(void) |
|
{ |
|
return cpu_pm_register_notifier(&mips_pm_notifier_block); |
|
} |
|
arch_initcall(mips_pm_init);
|
|
|