linux/arch/mips/loongson2ef/common/pm.c

159 lines
3.1 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* loongson-specific suspend support
*
* Copyright (C) 2009 Lemote Inc.
* Author: Wu Zhangjin <wuzhangjin@gmail.com>
*/
#include <linux/suspend.h>
#include <linux/interrupt.h>
#include <linux/pm.h>
#include <asm/i8259.h>
#include <asm/mipsregs.h>
#include <loongson.h>
static unsigned int __maybe_unused cached_master_mask; /* i8259A */
static unsigned int __maybe_unused cached_slave_mask;
static unsigned int __maybe_unused cached_bonito_irq_mask; /* bonito */
void arch_suspend_disable_irqs(void)
{
/* disable all mips events */
local_irq_disable();
#ifdef CONFIG_I8259
/* disable all events of i8259A */
cached_slave_mask = inb(PIC_SLAVE_IMR);
cached_master_mask = inb(PIC_MASTER_IMR);
outb(0xff, PIC_SLAVE_IMR);
inb(PIC_SLAVE_IMR);
outb(0xff, PIC_MASTER_IMR);
inb(PIC_MASTER_IMR);
#endif
/* disable all events of bonito */
cached_bonito_irq_mask = LOONGSON_INTEN;
LOONGSON_INTENCLR = 0xffff;
(void)LOONGSON_INTENCLR;
}
void arch_suspend_enable_irqs(void)
{
/* enable all mips events */
local_irq_enable();
#ifdef CONFIG_I8259
/* only enable the cached events of i8259A */
outb(cached_slave_mask, PIC_SLAVE_IMR);
outb(cached_master_mask, PIC_MASTER_IMR);
#endif
/* enable all cached events of bonito */
LOONGSON_INTENSET = cached_bonito_irq_mask;
(void)LOONGSON_INTENSET;
}
/*
* Setup the board-specific events for waking up loongson from wait mode
*/
void __weak setup_wakeup_events(void)
{
}
/*
* Check wakeup events
*/
int __weak wakeup_loongson(void)
{
return 1;
}
/*
* If the events are really what we want to wakeup the CPU, wake it up
* otherwise put the CPU asleep again.
*/
static void wait_for_wakeup_events(void)
{
while (!wakeup_loongson())
writel(readl(LOONGSON_CHIPCFG) & ~0x7, LOONGSON_CHIPCFG);
}
/*
* Stop all perf counters
*
* $24 is the control register of Loongson perf counter
*/
static inline void stop_perf_counters(void)
{
__write_64bit_c0_register($24, 0, 0);
}
static void loongson_suspend_enter(void)
{
unsigned int cached_cpu_freq;
/* setup wakeup events via enabling the IRQs */
setup_wakeup_events();
stop_perf_counters();
cached_cpu_freq = readl(LOONGSON_CHIPCFG);
/* Put CPU into wait mode */
writel(readl(LOONGSON_CHIPCFG) & ~0x7, LOONGSON_CHIPCFG);
/* wait for the given events to wakeup cpu from wait mode */
wait_for_wakeup_events();
writel(cached_cpu_freq, LOONGSON_CHIPCFG);
mmiowb();
}
void __weak mach_suspend(void)
{
}
void __weak mach_resume(void)
{
}
static int loongson_pm_enter(suspend_state_t state)
{
mach_suspend();
/* processor specific suspend */
loongson_suspend_enter();
mach_resume();
return 0;
}
static int loongson_pm_valid_state(suspend_state_t state)
{
switch (state) {
case PM_SUSPEND_ON:
case PM_SUSPEND_STANDBY:
case PM_SUSPEND_MEM:
return 1;
default:
return 0;
}
}
static const struct platform_suspend_ops loongson_pm_ops = {
.valid = loongson_pm_valid_state,
.enter = loongson_pm_enter,
};
static int __init loongson_pm_init(void)
{
suspend_set_ops(&loongson_pm_ops);
return 0;
}
arch_initcall(loongson_pm_init);