arch/powerpc/platforms/pseries/suspend.c - third_party/linux - Git at Google

 /*
   * 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>

 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.
 	 */
 	post_mobility_fixup();
 }

 /**
  * 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_KERNEL))
 		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, 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,
 	.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);
	/*
	* 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>

	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.
	*/
	post_mobility_fixup();
	}

	/**
	* 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_KERNEL))
	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, 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,
	.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);