mirror of https://gitee.com/openkylin/linux.git
114 lines
2.9 KiB
C
114 lines
2.9 KiB
C
|
/*
|
||
|
|
* Copyright (C) 2016 Imagination Technologies
|
||
|
|
* Author: Paul Burton <paul.burton@imgtec.com>
|
||
|
|
*
|
||
|
|
* This program is free software; you can redistribute it and/or modify it
|
||
|
|
* under the terms of the GNU General Public License as published by the
|
||
|
|
* Free Software Foundation; either version 2 of the License, or (at your
|
||
|
|
* option) any later version.
|
||
|
|
*/
|
||
|
|
|
||
|
|
#include <linux/delay.h>
|
||
|
|
#include <linux/io.h>
|
||
|
|
#include <linux/module.h>
|
||
|
|
#include <linux/pci.h>
|
||
|
|
#include <linux/pm.h>
|
||
|
|
|
||
|
|
static struct pci_dev *pm_dev;
|
||
|
|
static resource_size_t io_offset;
|
||
|
|
|
||
|
|
enum piix4_pm_io_reg {
|
||
|
|
PIIX4_FUNC3IO_PMSTS = 0x00,
|
||
|
|
#define PIIX4_FUNC3IO_PMSTS_PWRBTN_STS BIT(8)
|
||
|
|
PIIX4_FUNC3IO_PMCNTRL = 0x04,
|
||
|
|
#define PIIX4_FUNC3IO_PMCNTRL_SUS_EN BIT(13)
|
||
|
|
#define PIIX4_FUNC3IO_PMCNTRL_SUS_TYP_SOFF (0x0 << 10)
|
||
|
|
};
|
||
|
|
|
||
|
|
#define PIIX4_SUSPEND_MAGIC 0x00120002
|
||
|
|
|
||
|
|
static const int piix4_pm_io_region = PCI_BRIDGE_RESOURCES;
|
||
|
|
|
||
|
|
static void piix4_poweroff(void)
|
||
|
|
{
|
||
|
|
int spec_devid;
|
||
|
|
u16 sts;
|
||
|
|
|
||
|
|
/* Ensure the power button status is clear */
|
||
|
|
while (1) {
|
||
|
|
sts = inw(io_offset + PIIX4_FUNC3IO_PMSTS);
|
||
|
|
if (!(sts & PIIX4_FUNC3IO_PMSTS_PWRBTN_STS))
|
||
|
|
break;
|
||
|
|
outw(sts, io_offset + PIIX4_FUNC3IO_PMSTS);
|
||
|
|
}
|
||
|
|
|
||
|
|
/* Enable entry to suspend */
|
||
|
|
outw(PIIX4_FUNC3IO_PMCNTRL_SUS_TYP_SOFF | PIIX4_FUNC3IO_PMCNTRL_SUS_EN,
|
||
|
|
io_offset + PIIX4_FUNC3IO_PMCNTRL);
|
||
|
|
|
||
|
|
/* If the special cycle occurs too soon this doesn't work... */
|
||
|
|
mdelay(10);
|
||
|
|
|
||
|
|
/*
|
||
|
|
* The PIIX4 will enter the suspend state only after seeing a special
|
||
|
|
* cycle with the correct magic data on the PCI bus. Generate that
|
||
|
|
* cycle now.
|
||
|
|
*/
|
||
|
|
spec_devid = PCI_DEVID(0, PCI_DEVFN(0x1f, 0x7));
|
||
|
|
pci_bus_write_config_dword(pm_dev->bus, spec_devid, 0,
|
||
|
|
PIIX4_SUSPEND_MAGIC);
|
||
|
|
|
||
|
|
/* Give the system some time to power down, then error */
|
||
|
|
mdelay(1000);
|
||
|
|
pr_emerg("Unable to poweroff system\n");
|
||
|
|
}
|
||
|
|
|
||
|
|
static int piix4_poweroff_probe(struct pci_dev *dev,
|
||
|
|
const struct pci_device_id *id)
|
||
|
|
{
|
||
|
|
int res;
|
||
|
|
|
||
|
|
if (pm_dev)
|
||
|
|
return -EINVAL;
|
||
|
|
|
||
|
|
/* Request access to the PIIX4 PM IO registers */
|
||
|
|
res = pci_request_region(dev, piix4_pm_io_region,
|
||
|
|
"PIIX4 PM IO registers");
|
||
|
|
if (res) {
|
||
|
|
dev_err(&dev->dev, "failed to request PM IO registers: %d\n",
|
||
|
|
res);
|
||
|
|
return res;
|
||
|
|
}
|
||
|
|
|
||
|
|
pm_dev = dev;
|
||
|
|
io_offset = pci_resource_start(dev, piix4_pm_io_region);
|
||
|
|
pm_power_off = piix4_poweroff;
|
||
|
|
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
static void piix4_poweroff_remove(struct pci_dev *dev)
|
||
|
|
{
|
||
|
|
if (pm_power_off == piix4_poweroff)
|
||
|
|
pm_power_off = NULL;
|
||
|
|
|
||
|
|
pci_release_region(dev, piix4_pm_io_region);
|
||
|
|
pm_dev = NULL;
|
||
|
|
}
|
||
|
|
|
||
|
|
static const struct pci_device_id piix4_poweroff_ids[] = {
|
||
|
|
{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82371AB_3) },
|
||
|
|
{ 0 },
|
||
|
|
};
|
||
|
|
|
||
|
|
static struct pci_driver piix4_poweroff_driver = {
|
||
|
|
.name = "piix4-poweroff",
|
||
|
|
.id_table = piix4_poweroff_ids,
|
||
|
|
.probe = piix4_poweroff_probe,
|
||
|
|
.remove = piix4_poweroff_remove,
|
||
|
|
};
|
||
|
|
|
||
|
|
module_pci_driver(piix4_poweroff_driver);
|
||
|
|
MODULE_AUTHOR("Paul Burton <paul.burton@imgtec.com>");
|
||
|
|
MODULE_LICENSE("GPL");
|