blob: 5c43435472cc3b29ddc3c08c74014f9c2663cc9d [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (C) 2010 Brian King IBM Corporation
*/
#include <linux/cpu.h>
#include <linux/delay.h>
#include <linux/suspend.h>
#include <linux/stat.h>
#include <asm/firmware.h>
#include <asm/hvcall.h>
#include <asm/machdep.h>
#include <asm/mmu.h>
#include <asm/rtas.h>
#include <asm/topology.h>
static struct device suspend_dev;
/**
* pseries_suspend_begin - First phase of hibernation
*
* Check to ensure we are in a valid state to hibernate
*
* Return value:
* 0 on success / other on failure
**/
static int pseries_suspend_begin(u64 stream_id)
{
long vasi_state, rc;
unsigned long retbuf[PLPAR_HCALL_BUFSIZE];
/* Make sure the state is valid */
rc = plpar_hcall(H_VASI_STATE, retbuf, stream_id);
vasi_state = retbuf[0];
if (rc) {
pr_err("pseries_suspend_begin: vasi_state returned %ld\n",rc);
return rc;
} else if (vasi_state == H_VASI_ENABLED) {
return -EAGAIN;
} else if (vasi_state != H_VASI_SUSPENDING) {
pr_err("pseries_suspend_begin: vasi_state returned state %ld\n",
vasi_state);
return -EIO;
}
return 0;
}
/**
* pseries_suspend_enter - Final phase of hibernation
*
* Return value:
* 0 on success / other on failure
**/
static int pseries_suspend_enter(suspend_state_t state)
{
return rtas_ibm_suspend_me(NULL);
}
/**
* store_hibernate - Initiate partition hibernation
* @dev: subsys root device
* @attr: device attribute struct
* @buf: buffer
* @count: buffer size
*
* Write the stream ID received from the HMC to this file
* to trigger hibernating the partition
*
* Return value:
* number of bytes printed to buffer / other on failure
**/
static ssize_t store_hibernate(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
u64 stream_id;
int rc;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
stream_id = simple_strtoul(buf, NULL, 16);
do {
rc = pseries_suspend_begin(stream_id);
if (rc == -EAGAIN)
ssleep(1);
} while (rc == -EAGAIN);
if (!rc)
rc = pm_suspend(PM_SUSPEND_MEM);
if (!rc) {
rc = count;
post_mobility_fixup();
}
return rc;
}
#define USER_DT_UPDATE 0
#define KERN_DT_UPDATE 1
/**
* show_hibernate - Report device tree update responsibilty
* @dev: subsys root device
* @attr: device attribute struct
* @buf: buffer
*
* Report whether a device tree update is performed by the kernel after a
* resume, or if drmgr must coordinate the update from user space.
*
* Return value:
* 0 if drmgr is to initiate update, and 1 otherwise
**/
static ssize_t show_hibernate(struct device *dev,
struct device_attribute *attr,
char *buf)
{
return sprintf(buf, "%d\n", KERN_DT_UPDATE);
}
static DEVICE_ATTR(hibernate, 0644, show_hibernate, store_hibernate);
static struct bus_type suspend_subsys = {
.name = "power",
.dev_name = "power",
};
static const struct platform_suspend_ops pseries_suspend_ops = {
.valid = suspend_valid_only_mem,
.enter = pseries_suspend_enter,
};
/**
* pseries_suspend_sysfs_register - Register with sysfs
*
* Return value:
* 0 on success / other on failure
**/
static int pseries_suspend_sysfs_register(struct device *dev)
{
struct device *dev_root;
int rc;
if ((rc = subsys_system_register(&suspend_subsys, NULL)))
return rc;
dev->id = 0;
dev->bus = &suspend_subsys;
dev_root = bus_get_dev_root(&suspend_subsys);
if (dev_root) {
rc = device_create_file(dev_root, &dev_attr_hibernate);
put_device(dev_root);
if (rc)
goto subsys_unregister;
}
return 0;
subsys_unregister:
bus_unregister(&suspend_subsys);
return rc;
}
/**
* pseries_suspend_init - initcall for pSeries suspend
*
* Return value:
* 0 on success / other on failure
**/
static int __init pseries_suspend_init(void)
{
int rc;
if (!firmware_has_feature(FW_FEATURE_LPAR))
return 0;
if ((rc = pseries_suspend_sysfs_register(&suspend_dev)))
return rc;
suspend_set_ops(&pseries_suspend_ops);
return 0;
}
machine_device_initcall(pseries, pseries_suspend_init);