linux/linux-5.4.31/arch/mips/vr41xx/common/pmu.c

124 lines
2.5 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* pmu.c, Power Management Unit routines for NEC VR4100 series.
*
* Copyright (C) 2003-2007 Yoichi Yuasa <yuasa@linux-mips.org>
*/
#include <linux/cpu.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/ioport.h>
#include <linux/kernel.h>
#include <linux/pm.h>
#include <linux/sched.h>
#include <linux/types.h>
#include <asm/cacheflush.h>
#include <asm/cpu.h>
#include <asm/idle.h>
#include <asm/io.h>
#include <asm/processor.h>
#include <asm/reboot.h>
#define PMU_TYPE1_BASE 0x0b0000a0UL
#define PMU_TYPE1_SIZE 0x0eUL
#define PMU_TYPE2_BASE 0x0f0000c0UL
#define PMU_TYPE2_SIZE 0x10UL
#define PMUCNT2REG 0x06
#define SOFTRST 0x0010
static void __iomem *pmu_base;
#define pmu_read(offset) readw(pmu_base + (offset))
#define pmu_write(offset, value) writew((value), pmu_base + (offset))
static void __cpuidle vr41xx_cpu_wait(void)
{
local_irq_disable();
if (!need_resched())
/*
* "standby" sets IE bit of the CP0_STATUS to 1.
*/
__asm__("standby;\n");
else
local_irq_enable();
}
static inline void software_reset(void)
{
uint16_t pmucnt2;
switch (current_cpu_type()) {
case CPU_VR4122:
case CPU_VR4131:
case CPU_VR4133:
pmucnt2 = pmu_read(PMUCNT2REG);
pmucnt2 |= SOFTRST;
pmu_write(PMUCNT2REG, pmucnt2);
break;
default:
set_c0_status(ST0_BEV | ST0_ERL);
change_c0_config(CONF_CM_CMASK, CONF_CM_UNCACHED);
__flush_cache_all();
write_c0_wired(0);
__asm__("jr %0"::"r"(0xbfc00000));
break;
}
}
static void vr41xx_restart(char *command)
{
local_irq_disable();
software_reset();
while (1) ;
}
static void vr41xx_halt(void)
{
local_irq_disable();
printk(KERN_NOTICE "\nYou can turn off the power supply\n");
__asm__("hibernate;\n");
}
static int __init vr41xx_pmu_init(void)
{
unsigned long start, size;
switch (current_cpu_type()) {
case CPU_VR4111:
case CPU_VR4121:
start = PMU_TYPE1_BASE;
size = PMU_TYPE1_SIZE;
break;
case CPU_VR4122:
case CPU_VR4131:
case CPU_VR4133:
start = PMU_TYPE2_BASE;
size = PMU_TYPE2_SIZE;
break;
default:
printk("Unexpected CPU of NEC VR4100 series\n");
return -ENODEV;
}
if (request_mem_region(start, size, "PMU") == NULL)
return -EBUSY;
pmu_base = ioremap(start, size);
if (pmu_base == NULL) {
release_mem_region(start, size);
return -EBUSY;
}
cpu_wait = vr41xx_cpu_wait;
_machine_restart = vr41xx_restart;
_machine_halt = vr41xx_halt;
pm_power_off = vr41xx_halt;
return 0;
}
core_initcall(vr41xx_pmu_init);