/*
* Copyright (C) 2010 Brian King IBM Corporation
*
* 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.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#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>
#include "../../kernel/cacheinfo.h"
static u64 stream_id;
static struct device suspend_dev;
static DECLARE_COMPLETION(suspend_work);
static struct rtas_suspend_me_data suspend_data;
static atomic_t suspending;
/**
* 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(suspend_state_t state)
{
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_cpu - Suspend a single CPU
*
* Makes the H_JOIN call to suspend the CPU
*
**/
static int pseries_suspend_cpu(void)
{
if (atomic_read(&suspending))
return rtas_suspend_cpu(&suspend_data);
return 0;
}
/**
* pseries_suspend_enable_irqs
*
* Post suspend configuration updates
*
**/
static void pseries_suspend_enable_irqs(void)
{
/*
* Update configuration which can be modified based on device tree
* changes during resume.
*/
cacheinfo_cpu_offline(smp_processor_id());
post_mobility_fixup();
cacheinfo_cpu_online(smp_processor_id());
}
/**
* pseries_suspend_enter - Final phase of hibernation
*
* Return value:
* 0 on success / other on failure
**/
static int pseries_suspend_enter(suspend_state_t state)
{
int rc = rtas_suspend_last_cpu(&suspend_data);
atomic_set(&suspending, 0);
atomic_set(&suspend_data.done, 1);
return rc;
}
/**
* pseries_prepare_late - Prepare to suspend all other CPUs
*
* Return value:
* 0 on success / other on failure
**/
static int pseries_prepare_late(void)
{
atomic_set(&suspending, 1);
atomic_set(&suspend_data.working, 0);
atomic_set(&suspend_data.done, 0);
atomic_set(&suspend_data.error, 0);
suspend_data.complete = &suspend_work;
reinit_completion(&suspend_work);
return 0;
}
/**
* 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)
{
cpumask_var_t offline_mask;
int rc;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
if (!alloc_cpumask_var(&offline_mask, GFP_TEMPORARY))
return -ENOMEM;
stream_id = simple_strtoul(buf, NULL, 16);
do {
rc = pseries_suspend_begin(PM_SUSPEND_MEM);
if (rc == -EAGAIN)
ssleep(1);
} while (rc == -EAGAIN);
if (!rc) {
/* All present CPUs must be online */
cpumask_andnot(offline_mask, cpu_present_mask,
cpu_online_mask);
rc = rtas_online_cpus_mask(offline_mask);
if (rc) {
pr_err("%s: Could not bring present CPUs online.\n",
__func__);
goto out;
}
stop_topology_update();
rc = pm_suspend(PM_SUSPEND_MEM);
start_topology_update();
/* Take down CPUs not online prior to suspend */
if (!rtas_offline_cpus_mask(offline_mask))
pr_warn("%s: Could not restore CPUs to offline "
"state.\n", __func__);
}
stream_id = 0;
if (!rc)
rc = count;
out:
free_cpumask_var(offline_mask);
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, S_IWUSR | S_IRUGO,
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,
.begin = pseries_suspend_begin,
.prepare_late = pseries_prepare_late,
.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)
{
int rc;
if ((rc = subsys_system_register(&suspend_subsys, NULL)))
return rc;
dev->id = 0;
dev->bus = &suspend_subsys;
if ((rc = device_create_file(suspend_subsys.dev_root, &dev_attr_hibernate)))
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;
suspend_data.token = rtas_token("ibm,suspend-me");
if (suspend_data.token == RTAS_UNKNOWN_SERVICE)
return 0;
if ((rc = pseries_suspend_sysfs_register(&suspend_dev)))
return rc;
ppc_md.suspend_disable_cpu = pseries_suspend_cpu;
ppc_md.suspend_enable_irqs = pseries_suspend_enable_irqs;
suspend_set_ops(&pseries_suspend_ops);
return 0;
}
machine_device_initcall(pseries, pseries_suspend_init);