acrn-kernel/arch/sparc/kernel/pmc.c

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/* pmc - Driver implementation for power management functions
* of Power Management Controller (PMC) on SPARCstation-Voyager.
*
* Copyright (c) 2002 Eric Brower (ebrower@usa.net)
*/
#include <linux/kernel.h>
#include <linux/fs.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/miscdevice.h>
#include <linux/pm.h>
#include <asm/io.h>
#include <asm/sbus.h>
#include <asm/oplib.h>
#include <asm/uaccess.h>
#include <asm/auxio.h>
/* Debug
*
* #define PMC_DEBUG_LED
* #define PMC_NO_IDLE
*/
#define PMC_MINOR MISC_DYNAMIC_MINOR
#define PMC_OBPNAME "SUNW,pmc"
#define PMC_DEVNAME "pmc"
#define PMC_IDLE_REG 0x00
#define PMC_IDLE_ON 0x01
volatile static u8 __iomem *regs;
static int pmc_regsize;
#define pmc_readb(offs) (sbus_readb(regs+offs))
#define pmc_writeb(val, offs) (sbus_writeb(val, regs+offs))
/*
* CPU idle callback function
* See .../arch/sparc/kernel/process.c
*/
void pmc_swift_idle(void)
{
#ifdef PMC_DEBUG_LED
set_auxio(0x00, AUXIO_LED);
#endif
pmc_writeb(pmc_readb(PMC_IDLE_REG) | PMC_IDLE_ON, PMC_IDLE_REG);
#ifdef PMC_DEBUG_LED
set_auxio(AUXIO_LED, 0x00);
#endif
}
static inline void pmc_free(void)
{
sbus_iounmap(regs, pmc_regsize);
}
static int __init pmc_probe(void)
{
struct sbus_bus *sbus = NULL;
struct sbus_dev *sdev = NULL;
for_each_sbus(sbus) {
for_each_sbusdev(sdev, sbus) {
if (!strcmp(sdev->prom_name, PMC_OBPNAME)) {
goto sbus_done;
}
}
}
sbus_done:
if (!sdev) {
return -ENODEV;
}
pmc_regsize = sdev->reg_addrs[0].reg_size;
regs = sbus_ioremap(&sdev->resource[0], 0,
pmc_regsize, PMC_OBPNAME);
if (!regs) {
printk(KERN_ERR "%s: unable to map registers\n", PMC_DEVNAME);
return -ENODEV;
}
#ifndef PMC_NO_IDLE
/* Assign power management IDLE handler */
pm_idle = pmc_swift_idle;
#endif
printk(KERN_INFO "%s: power management initialized\n", PMC_DEVNAME);
return 0;
}
/* This driver is not critical to the boot process
* and is easiest to ioremap when SBus is already
* initialized, so we install ourselves thusly:
*/
__initcall(pmc_probe);