[deliverable/linux.git] / drivers / acpi / acpi_memhotplug.c

/*
 * Copyright (C) 2004 Intel Corporation <naveen.b.s@intel.com>
 *
 * All rights reserved.
 *
 * 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, GOOD TITLE or
 * NON INFRINGEMENT.  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., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 *
 * ACPI based HotPlug driver that supports Memory Hotplug
 * This driver fields notifications from firmare for memory add
 * and remove operations and alerts the VM of the affected memory
 * ranges.
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/memory_hotplug.h>
#include <acpi/acpi_drivers.h>

#define ACPI_MEMORY_DEVICE_COMPONENT		0x08000000UL
#define ACPI_MEMORY_DEVICE_CLASS		"memory"
#define ACPI_MEMORY_DEVICE_HID			"PNP0C80"
#define ACPI_MEMORY_DEVICE_NAME			"Hotplug Mem Device"

#define _COMPONENT		ACPI_MEMORY_DEVICE_COMPONENT

ACPI_MODULE_NAME("acpi_memhotplug");
MODULE_AUTHOR("Naveen B S <naveen.b.s@intel.com>");
MODULE_DESCRIPTION("Hotplug Mem Driver");
MODULE_LICENSE("GPL");

/* ACPI _STA method values */
#define ACPI_MEMORY_STA_PRESENT		(0x00000001UL)
#define ACPI_MEMORY_STA_ENABLED		(0x00000002UL)
#define ACPI_MEMORY_STA_FUNCTIONAL	(0x00000008UL)

/* Memory Device States */
#define MEMORY_INVALID_STATE	0
#define MEMORY_POWER_ON_STATE	1
#define MEMORY_POWER_OFF_STATE	2

static int acpi_memory_device_add(struct acpi_device *device);
static int acpi_memory_device_remove(struct acpi_device *device, int type);
static int acpi_memory_device_start(struct acpi_device *device);

static struct acpi_driver acpi_memory_device_driver = {
	.name = "acpi_memhotplug",
	.class = ACPI_MEMORY_DEVICE_CLASS,
	.ids = ACPI_MEMORY_DEVICE_HID,
	.ops = {
		.add = acpi_memory_device_add,
		.remove = acpi_memory_device_remove,
		.start = acpi_memory_device_start,
		},
};

struct acpi_memory_info {
	struct list_head list;
	u64 start_addr;		/* Memory Range start physical addr */
	u64 length;		/* Memory Range length */
	unsigned short caching;	/* memory cache attribute */
	unsigned short write_protect;	/* memory read/write attribute */
	unsigned int enabled:1;
};

struct acpi_memory_device {
	struct acpi_device * device;
	unsigned int state;	/* State of the memory device */
	struct list_head res_list;
};

static int acpi_hotmem_initialized;

static acpi_status
acpi_memory_get_resource(struct acpi_resource *resource, void *context)
{
	struct acpi_memory_device *mem_device = context;
	struct acpi_resource_address64 address64;
	struct acpi_memory_info *info, *new;
	acpi_status status;

	status = acpi_resource_to_address64(resource, &address64);
	if (ACPI_FAILURE(status) ||
	    (address64.resource_type != ACPI_MEMORY_RANGE))
		return AE_OK;

	list_for_each_entry(info, &mem_device->res_list, list) {
		/* Can we combine the resource range information? */
		if ((info->caching == address64.info.mem.caching) &&
		    (info->write_protect == address64.info.mem.write_protect) &&
		    (info->start_addr + info->length == address64.minimum)) {
			info->length += address64.address_length;
			return AE_OK;
		}
	}

	new = kzalloc(sizeof(struct acpi_memory_info), GFP_KERNEL);
	if (!new)
		return AE_ERROR;

	INIT_LIST_HEAD(&new->list);
	new->caching = address64.info.mem.caching;
	new->write_protect = address64.info.mem.write_protect;
	new->start_addr = address64.minimum;
	new->length = address64.address_length;
	list_add_tail(&new->list, &mem_device->res_list);

	return AE_OK;
}

static int
acpi_memory_get_device_resources(struct acpi_memory_device *mem_device)
{
	acpi_status status;
	struct acpi_memory_info *info, *n;


	if (!list_empty(&mem_device->res_list))
		return 0;

	status = acpi_walk_resources(mem_device->device->handle, METHOD_NAME__CRS,
				     acpi_memory_get_resource, mem_device);
	if (ACPI_FAILURE(status)) {
		list_for_each_entry_safe(info, n, &mem_device->res_list, list)
			kfree(info);
		INIT_LIST_HEAD(&mem_device->res_list);
		return -EINVAL;
	}

	return 0;
}

static int
acpi_memory_get_device(acpi_handle handle,
		       struct acpi_memory_device **mem_device)
{
	acpi_status status;
	acpi_handle phandle;
	struct acpi_device *device = NULL;
	struct acpi_device *pdevice = NULL;


	if (!acpi_bus_get_device(handle, &device) && device)
		goto end;

	status = acpi_get_parent(handle, &phandle);
	if (ACPI_FAILURE(status)) {
		ACPI_EXCEPTION((AE_INFO, status, "Cannot find acpi parent"));
		return -EINVAL;
	}

	/* Get the parent device */
	status = acpi_bus_get_device(phandle, &pdevice);
	if (ACPI_FAILURE(status)) {
		ACPI_EXCEPTION((AE_INFO, status, "Cannot get acpi bus device"));
		return -EINVAL;
	}

	/*
	 * Now add the notified device.  This creates the acpi_device
	 * and invokes .add function
	 */
	status = acpi_bus_add(&device, pdevice, handle, ACPI_BUS_TYPE_DEVICE);
	if (ACPI_FAILURE(status)) {
		ACPI_EXCEPTION((AE_INFO, status, "Cannot add acpi bus"));
		return -EINVAL;
	}

      end:
	*mem_device = acpi_driver_data(device);
	if (!(*mem_device)) {
		printk(KERN_ERR "\n driver data not found");
		return -ENODEV;
	}

	return 0;
}

static int acpi_memory_check_device(struct acpi_memory_device *mem_device)
{
	unsigned long current_status;


	/* Get device present/absent information from the _STA */
	if (ACPI_FAILURE(acpi_evaluate_integer(mem_device->device->handle, "_STA",
					       NULL, &current_status)))
		return -ENODEV;
	/*
	 * Check for device status. Device should be
	 * present/enabled/functioning.
	 */
	if (!((current_status & ACPI_MEMORY_STA_PRESENT)
	      && (current_status & ACPI_MEMORY_STA_ENABLED)
	      && (current_status & ACPI_MEMORY_STA_FUNCTIONAL)))
		return -ENODEV;

	return 0;
}

static int acpi_memory_enable_device(struct acpi_memory_device *mem_device)
{
	int result, num_enabled = 0;
	struct acpi_memory_info *info;
	int node;


	/* Get the range from the _CRS */
	result = acpi_memory_get_device_resources(mem_device);
	if (result) {
		printk(KERN_ERR PREFIX "get_device_resources failed\n");
		mem_device->state = MEMORY_INVALID_STATE;
		return result;
	}

	node = acpi_get_node(mem_device->device->handle);
	/*
	 * Tell the VM there is more memory here...
	 * Note: Assume that this function returns zero on success
	 * We don't have memory-hot-add rollback function,now.
	 * (i.e. memory-hot-remove function)
	 */
	list_for_each_entry(info, &mem_device->res_list, list) {
		if (info->enabled) { /* just sanity check...*/
			num_enabled++;
			continue;
		}

		if (node < 0)
			node = memory_add_physaddr_to_nid(info->start_addr);

		result = add_memory(node, info->start_addr, info->length);
		if (result)
			continue;
		info->enabled = 1;
		num_enabled++;
	}
	if (!num_enabled) {
		printk(KERN_ERR PREFIX "add_memory failed\n");
		mem_device->state = MEMORY_INVALID_STATE;
		return -EINVAL;
	}

	return result;
}

static int acpi_memory_powerdown_device(struct acpi_memory_device *mem_device)
{
	acpi_status status;
	struct acpi_object_list arg_list;
	union acpi_object arg;
	unsigned long current_status;


	/* Issue the _EJ0 command */
	arg_list.count = 1;
	arg_list.pointer = &arg;
	arg.type = ACPI_TYPE_INTEGER;
	arg.integer.value = 1;
	status = acpi_evaluate_object(mem_device->device->handle,
				      "_EJ0", &arg_list, NULL);
	/* Return on _EJ0 failure */
	if (ACPI_FAILURE(status)) {
		ACPI_EXCEPTION((AE_INFO, status, "_EJ0 failed"));
		return -ENODEV;
	}

	/* Evalute _STA to check if the device is disabled */
	status = acpi_evaluate_integer(mem_device->device->handle, "_STA",
				       NULL, &current_status);
	if (ACPI_FAILURE(status))
		return -ENODEV;

	/* Check for device status.  Device should be disabled */
	if (current_status & ACPI_MEMORY_STA_ENABLED)
		return -EINVAL;

	return 0;
}

static int acpi_memory_disable_device(struct acpi_memory_device *mem_device)
{
	int result;
	struct acpi_memory_info *info, *n;


	/*
	 * Ask the VM to offline this memory range.
	 * Note: Assume that this function returns zero on success
	 */
	list_for_each_entry_safe(info, n, &mem_device->res_list, list) {
		if (info->enabled) {
			result = remove_memory(info->start_addr, info->length);
			if (result)
				return result;
		}
		kfree(info);
	}

	/* Power-off and eject the device */
	result = acpi_memory_powerdown_device(mem_device);
	if (result) {
		/* Set the status of the device to invalid */
		mem_device->state = MEMORY_INVALID_STATE;
		return result;
	}

	mem_device->state = MEMORY_POWER_OFF_STATE;
	return result;
}

static void acpi_memory_device_notify(acpi_handle handle, u32 event, void *data)
{
	struct acpi_memory_device *mem_device;
	struct acpi_device *device;


	switch (event) {
	case ACPI_NOTIFY_BUS_CHECK:
		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
				  "\nReceived BUS CHECK notification for device\n"));
		/* Fall Through */
	case ACPI_NOTIFY_DEVICE_CHECK:
		if (event == ACPI_NOTIFY_DEVICE_CHECK)
			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
					  "\nReceived DEVICE CHECK notification for device\n"));
		if (acpi_memory_get_device(handle, &mem_device)) {
			printk(KERN_ERR PREFIX "Cannot find driver data\n");
			return;
		}

		if (!acpi_memory_check_device(mem_device)) {
			if (acpi_memory_enable_device(mem_device))
				printk(KERN_ERR PREFIX
					    "Cannot enable memory device\n");
		}
		break;
	case ACPI_NOTIFY_EJECT_REQUEST:
		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
				  "\nReceived EJECT REQUEST notification for device\n"));

		if (acpi_bus_get_device(handle, &device)) {
			printk(KERN_ERR PREFIX "Device doesn't exist\n");
			break;
		}
		mem_device = acpi_driver_data(device);
		if (!mem_device) {
			printk(KERN_ERR PREFIX "Driver Data is NULL\n");
			break;
		}

		/*
		 * Currently disabling memory device from kernel mode
		 * TBD: Can also be disabled from user mode scripts
		 * TBD: Can also be disabled by Callback registration
		 *      with generic sysfs driver
		 */
		if (acpi_memory_disable_device(mem_device))
			printk(KERN_ERR PREFIX
				    "Disable memory device\n");
		/*
		 * TBD: Invoke acpi_bus_remove to cleanup data structures
		 */
		break;
	default:
		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
				  "Unsupported event [0x%x]\n", event));
		break;
	}

	return;
}

static int acpi_memory_device_add(struct acpi_device *device)
{
	int result;
	struct acpi_memory_device *mem_device = NULL;


	if (!device)
		return -EINVAL;

	mem_device = kzalloc(sizeof(struct acpi_memory_device), GFP_KERNEL);
	if (!mem_device)
		return -ENOMEM;

	INIT_LIST_HEAD(&mem_device->res_list);
	mem_device->device = device;
	sprintf(acpi_device_name(device), "%s", ACPI_MEMORY_DEVICE_NAME);
	sprintf(acpi_device_class(device), "%s", ACPI_MEMORY_DEVICE_CLASS);
	acpi_driver_data(device) = mem_device;

	/* Get the range from the _CRS */
	result = acpi_memory_get_device_resources(mem_device);
	if (result) {
		kfree(mem_device);
		return result;
	}

	/* Set the device state */
	mem_device->state = MEMORY_POWER_ON_STATE;

	printk(KERN_DEBUG "%s \n", acpi_device_name(device));

	return result;
}

static int acpi_memory_device_remove(struct acpi_device *device, int type)
{
	struct acpi_memory_device *mem_device = NULL;


	if (!device || !acpi_driver_data(device))
		return -EINVAL;

	mem_device = acpi_driver_data(device);
	kfree(mem_device);

	return 0;
}

static int acpi_memory_device_start (struct acpi_device *device)
{
	struct acpi_memory_device *mem_device;
	int result = 0;

	/*
	 * Early boot code has recognized memory area by EFI/E820.
	 * If DSDT shows these memory devices on boot, hotplug is not necessary
	 * for them. So, it just returns until completion of this driver's
	 * start up.
	 */
	if (!acpi_hotmem_initialized)
		return 0;

	mem_device = acpi_driver_data(device);

	if (!acpi_memory_check_device(mem_device)) {
		/* call add_memory func */
		result = acpi_memory_enable_device(mem_device);
		if (result)
			ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
				"Error in acpi_memory_enable_device\n"));
	}
	return result;
}

/*
 * Helper function to check for memory device
 */
static acpi_status is_memory_device(acpi_handle handle)
{
	char *hardware_id;
	acpi_status status;
	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
	struct acpi_device_info *info;


	status = acpi_get_object_info(handle, &buffer);
	if (ACPI_FAILURE(status))
		return status;

	info = buffer.pointer;
	if (!(info->valid & ACPI_VALID_HID)) {
		kfree(buffer.pointer);
		return AE_ERROR;
	}

	hardware_id = info->hardware_id.value;
	if ((hardware_id == NULL) ||
	    (strcmp(hardware_id, ACPI_MEMORY_DEVICE_HID)))
		status = AE_ERROR;

	kfree(buffer.pointer);
	return status;
}

static acpi_status
acpi_memory_register_notify_handler(acpi_handle handle,
				    u32 level, void *ctxt, void **retv)
{
	acpi_status status;


	status = is_memory_device(handle);
	if (ACPI_FAILURE(status))
		return AE_OK;	/* continue */

	status = acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
					     acpi_memory_device_notify, NULL);
	/* continue */
	return AE_OK;
}

static acpi_status
acpi_memory_deregister_notify_handler(acpi_handle handle,
				      u32 level, void *ctxt, void **retv)
{
	acpi_status status;


	status = is_memory_device(handle);
	if (ACPI_FAILURE(status))
		return AE_OK;	/* continue */

	status = acpi_remove_notify_handler(handle,
					    ACPI_SYSTEM_NOTIFY,
					    acpi_memory_device_notify);

	return AE_OK;	/* continue */
}

static int __init acpi_memory_device_init(void)
{
	int result;
	acpi_status status;


	result = acpi_bus_register_driver(&acpi_memory_device_driver);

	if (result < 0)
		return -ENODEV;

	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
				     ACPI_UINT32_MAX,
				     acpi_memory_register_notify_handler,
				     NULL, NULL);

	if (ACPI_FAILURE(status)) {
		ACPI_EXCEPTION((AE_INFO, status, "walk_namespace failed"));
		acpi_bus_unregister_driver(&acpi_memory_device_driver);
		return -ENODEV;
	}

	acpi_hotmem_initialized = 1;
	return 0;
}

static void __exit acpi_memory_device_exit(void)
{
	acpi_status status;


	/*
	 * Adding this to un-install notification handlers for all the device
	 * handles.
	 */
	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
				     ACPI_UINT32_MAX,
				     acpi_memory_deregister_notify_handler,
				     NULL, NULL);

	if (ACPI_FAILURE(status))
		ACPI_EXCEPTION((AE_INFO, status, "walk_namespace failed"));

	acpi_bus_unregister_driver(&acpi_memory_device_driver);

	return;
}

module_init(acpi_memory_device_init);
module_exit(acpi_memory_device_exit);
Commit	Line	Data
1da177e4 LT	1	/*
	2	* Copyright (C) 2004 Intel Corporation <naveen.b.s@intel.com>
	3	*
	4	* All rights reserved.
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License as published by
	8	* the Free Software Foundation; either version 2 of the License, or (at
	9	* your option) any later version.
	10	*
	11	* This program is distributed in the hope that it will be useful, but
	12	* WITHOUT ANY WARRANTY; without even the implied warranty of
	13	* MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
	14	* NON INFRINGEMENT. See the GNU General Public License for more
	15	* details.
	16	*
	17	* You should have received a copy of the GNU General Public License
	18	* along with this program; if not, write to the Free Software
	19	* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
	20	*
	21	*
	22	* ACPI based HotPlug driver that supports Memory Hotplug
	23	* This driver fields notifications from firmare for memory add
	24	* and remove operations and alerts the VM of the affected memory
	25	* ranges.
	26	*/
	27
	28	#include <linux/kernel.h>
	29	#include <linux/module.h>
	30	#include <linux/init.h>
	31	#include <linux/types.h>
	32	#include <linux/memory_hotplug.h>
	33	#include <acpi/acpi_drivers.h>
	34
1da177e4 LT	35	#define ACPI_MEMORY_DEVICE_COMPONENT 0x08000000UL
	36	#define ACPI_MEMORY_DEVICE_CLASS "memory"
	37	#define ACPI_MEMORY_DEVICE_HID "PNP0C80"
1da177e4 LT	38	#define ACPI_MEMORY_DEVICE_NAME "Hotplug Mem Device"
	39
	40	#define _COMPONENT ACPI_MEMORY_DEVICE_COMPONENT
	41
f52fd66d LB	42	ACPI_MODULE_NAME("acpi_memhotplug");
f52fd66d LB	43	MODULE_AUTHOR("Naveen B S <naveen.b.s@intel.com>");
7cda93e0	44	MODULE_DESCRIPTION("Hotplug Mem Driver");
1da177e4 LT	45	MODULE_LICENSE("GPL");
	46
	47	/* ACPI _STA method values */
	48	#define ACPI_MEMORY_STA_PRESENT (0x00000001UL)
	49	#define ACPI_MEMORY_STA_ENABLED (0x00000002UL)
	50	#define ACPI_MEMORY_STA_FUNCTIONAL (0x00000008UL)
	51
	52	/* Memory Device States */
	53	#define MEMORY_INVALID_STATE 0
	54	#define MEMORY_POWER_ON_STATE 1
	55	#define MEMORY_POWER_OFF_STATE 2
	56
4be44fcd LB	57	static int acpi_memory_device_add(struct acpi_device *device);
4be44fcd LB	58	static int acpi_memory_device_remove(struct acpi_device *device, int type);
1f425994	59	static int acpi_memory_device_start(struct acpi_device *device);
1da177e4 LT	60
1da177e4 LT	61	static struct acpi_driver acpi_memory_device_driver = {
c2b6705b	62	.name = "acpi_memhotplug",
4be44fcd LB	63	.class = ACPI_MEMORY_DEVICE_CLASS,
	64	.ids = ACPI_MEMORY_DEVICE_HID,
	65	.ops = {
	66	.add = acpi_memory_device_add,
	67	.remove = acpi_memory_device_remove,
1f425994	68	.start = acpi_memory_device_start,
4be44fcd	69	},
1da177e4 LT	70	};
1da177e4 LT	71
9ac02398 KH	72	struct acpi_memory_info {
	73	struct list_head list;
	74	u64 start_addr; /* Memory Range start physical addr */
	75	u64 length; /* Memory Range length */
	76	unsigned short caching; /* memory cache attribute */
	77	unsigned short write_protect; /* memory read/write attribute */
	78	unsigned int enabled:1;
	79	};
	80
1da177e4	81	struct acpi_memory_device {
3b74863d	82	struct acpi_device * device;
4be44fcd	83	unsigned int state; /* State of the memory device */
9ac02398	84	struct list_head res_list;
1da177e4 LT	85	};
1da177e4 LT	86
887b9593 YG	87	static int acpi_hotmem_initialized;
887b9593 YG	88
9ac02398 KH	89	static acpi_status
	90	acpi_memory_get_resource(struct acpi_resource resource, void context)
	91	{
	92	struct acpi_memory_device *mem_device = context;
	93	struct acpi_resource_address64 address64;
	94	struct acpi_memory_info info, new;
	95	acpi_status status;
	96
	97	status = acpi_resource_to_address64(resource, &address64);
	98	if (ACPI_FAILURE(status) \|\|
	99	(address64.resource_type != ACPI_MEMORY_RANGE))
	100	return AE_OK;
	101
	102	list_for_each_entry(info, &mem_device->res_list, list) {
	103	/* Can we combine the resource range information? */
	104	if ((info->caching == address64.info.mem.caching) &&
	105	(info->write_protect == address64.info.mem.write_protect) &&
	106	(info->start_addr + info->length == address64.minimum)) {
	107	info->length += address64.address_length;
	108	return AE_OK;
	109	}
	110	}
	111
	112	new = kzalloc(sizeof(struct acpi_memory_info), GFP_KERNEL);
	113	if (!new)
	114	return AE_ERROR;
	115
	116	INIT_LIST_HEAD(&new->list);
	117	new->caching = address64.info.mem.caching;
	118	new->write_protect = address64.info.mem.write_protect;
	119	new->start_addr = address64.minimum;
	120	new->length = address64.address_length;
	121	list_add_tail(&new->list, &mem_device->res_list);
	122
	123	return AE_OK;
	124	}
	125
1da177e4 LT	126	static int
	127	acpi_memory_get_device_resources(struct acpi_memory_device *mem_device)
	128	{
	129	acpi_status status;
9ac02398	130	struct acpi_memory_info info, n;
1da177e4	131
1da177e4	132
5d2870fa KH	133	if (!list_empty(&mem_device->res_list))
	134	return 0;
	135
b8632785	136	status = acpi_walk_resources(mem_device->device->handle, METHOD_NAME__CRS,
9ac02398 KH	137	acpi_memory_get_resource, mem_device);
	138	if (ACPI_FAILURE(status)) {
	139	list_for_each_entry_safe(info, n, &mem_device->res_list, list)
	140	kfree(info);
5d2870fa	141	INIT_LIST_HEAD(&mem_device->res_list);
d550d98d	142	return -EINVAL;
1da177e4 LT	143	}
1da177e4 LT	144
d550d98d	145	return 0;
1da177e4 LT	146	}
	147
	148	static int
	149	acpi_memory_get_device(acpi_handle handle,
4be44fcd	150	struct acpi_memory_device **mem_device)
1da177e4 LT	151	{
	152	acpi_status status;
	153	acpi_handle phandle;
	154	struct acpi_device *device = NULL;
	155	struct acpi_device *pdevice = NULL;
	156
1da177e4 LT	157
	158	if (!acpi_bus_get_device(handle, &device) && device)
	159	goto end;
	160
	161	status = acpi_get_parent(handle, &phandle);
	162	if (ACPI_FAILURE(status)) {
a6fc6720	163	ACPI_EXCEPTION((AE_INFO, status, "Cannot find acpi parent"));
d550d98d	164	return -EINVAL;
1da177e4 LT	165	}
	166
	167	/* Get the parent device */
	168	status = acpi_bus_get_device(phandle, &pdevice);
	169	if (ACPI_FAILURE(status)) {
a6fc6720	170	ACPI_EXCEPTION((AE_INFO, status, "Cannot get acpi bus device"));
d550d98d	171	return -EINVAL;
1da177e4 LT	172	}
	173
	174	/*
	175	* Now add the notified device. This creates the acpi_device
	176	* and invokes .add function
	177	*/
	178	status = acpi_bus_add(&device, pdevice, handle, ACPI_BUS_TYPE_DEVICE);
	179	if (ACPI_FAILURE(status)) {
a6fc6720	180	ACPI_EXCEPTION((AE_INFO, status, "Cannot add acpi bus"));
d550d98d	181	return -EINVAL;
1da177e4 LT	182	}
1da177e4 LT	183
4be44fcd	184	end:
1da177e4 LT	185	*mem_device = acpi_driver_data(device);
1da177e4 LT	186	if (!(*mem_device)) {
4be44fcd	187	printk(KERN_ERR "\n driver data not found");
d550d98d	188	return -ENODEV;
1da177e4 LT	189	}
1da177e4 LT	190
d550d98d	191	return 0;
1da177e4 LT	192	}
1da177e4 LT	193
4be44fcd	194	static int acpi_memory_check_device(struct acpi_memory_device *mem_device)
1da177e4 LT	195	{
	196	unsigned long current_status;
	197
1da177e4 LT	198
1da177e4 LT	199	/* Get device present/absent information from the _STA */
b8632785	200	if (ACPI_FAILURE(acpi_evaluate_integer(mem_device->device->handle, "_STA",
4be44fcd	201	NULL, &current_status)))
d550d98d	202	return -ENODEV;
1da177e4 LT	203	/*
	204	* Check for device status. Device should be
	205	* present/enabled/functioning.
	206	*/
	207	if (!((current_status & ACPI_MEMORY_STA_PRESENT)
4be44fcd LB	208	&& (current_status & ACPI_MEMORY_STA_ENABLED)
4be44fcd LB	209	&& (current_status & ACPI_MEMORY_STA_FUNCTIONAL)))
d550d98d	210	return -ENODEV;
1da177e4	211
d550d98d	212	return 0;
1da177e4 LT	213	}
1da177e4 LT	214
4be44fcd	215	static int acpi_memory_enable_device(struct acpi_memory_device *mem_device)
1da177e4	216	{
9ac02398 KH	217	int result, num_enabled = 0;
9ac02398 KH	218	struct acpi_memory_info *info;
1e3590e2	219	int node;
1da177e4	220
1da177e4 LT	221
	222	/* Get the range from the _CRS */
	223	result = acpi_memory_get_device_resources(mem_device);
	224	if (result) {
6468463a	225	printk(KERN_ERR PREFIX "get_device_resources failed\n");
1da177e4 LT	226	mem_device->state = MEMORY_INVALID_STATE;
	227	return result;
	228	}
	229
b8632785	230	node = acpi_get_node(mem_device->device->handle);
1da177e4 LT	231	/*
	232	* Tell the VM there is more memory here...
	233	* Note: Assume that this function returns zero on success
9ac02398 KH	234	* We don't have memory-hot-add rollback function,now.
9ac02398 KH	235	* (i.e. memory-hot-remove function)
1da177e4	236	*/
9ac02398	237	list_for_each_entry(info, &mem_device->res_list, list) {
fa25d8d6	238	if (info->enabled) { /* just sanity check...*/
dd56a8e3 YG	239	num_enabled++;
	240	continue;
	241	}
8c2676a5 KM	242
	243	if (node < 0)
	244	node = memory_add_physaddr_to_nid(info->start_addr);
	245
bc02af93	246	result = add_memory(node, info->start_addr, info->length);
9ac02398 KH	247	if (result)
	248	continue;
	249	info->enabled = 1;
	250	num_enabled++;
	251	}
	252	if (!num_enabled) {
0a1f1ab8	253	printk(KERN_ERR PREFIX "add_memory failed\n");
1da177e4	254	mem_device->state = MEMORY_INVALID_STATE;
9ac02398	255	return -EINVAL;
1da177e4 LT	256	}
	257
	258	return result;
	259	}
	260
4be44fcd	261	static int acpi_memory_powerdown_device(struct acpi_memory_device *mem_device)
1da177e4 LT	262	{
1da177e4 LT	263	acpi_status status;
4be44fcd	264	struct acpi_object_list arg_list;
1da177e4 LT	265	union acpi_object arg;
	266	unsigned long current_status;
	267
1da177e4 LT	268
	269	/* Issue the _EJ0 command */
	270	arg_list.count = 1;
	271	arg_list.pointer = &arg;
	272	arg.type = ACPI_TYPE_INTEGER;
	273	arg.integer.value = 1;
b8632785	274	status = acpi_evaluate_object(mem_device->device->handle,
4be44fcd	275	"_EJ0", &arg_list, NULL);
1da177e4 LT	276	/* Return on _EJ0 failure */
1da177e4 LT	277	if (ACPI_FAILURE(status)) {
a6fc6720	278	ACPI_EXCEPTION((AE_INFO, status, "_EJ0 failed"));
d550d98d	279	return -ENODEV;
1da177e4 LT	280	}
	281
	282	/* Evalute _STA to check if the device is disabled */
b8632785	283	status = acpi_evaluate_integer(mem_device->device->handle, "_STA",
4be44fcd	284	NULL, &current_status);
1da177e4	285	if (ACPI_FAILURE(status))
d550d98d	286	return -ENODEV;
1da177e4 LT	287
	288	/* Check for device status. Device should be disabled */
	289	if (current_status & ACPI_MEMORY_STA_ENABLED)
d550d98d	290	return -EINVAL;
1da177e4	291
d550d98d	292	return 0;
1da177e4 LT	293	}
1da177e4 LT	294
4be44fcd	295	static int acpi_memory_disable_device(struct acpi_memory_device *mem_device)
1da177e4 LT	296	{
1da177e4 LT	297	int result;
9ac02398	298	struct acpi_memory_info info, n;
1da177e4	299
1da177e4 LT	300
	301	/*
	302	* Ask the VM to offline this memory range.
	303	* Note: Assume that this function returns zero on success
	304	*/
9ac02398 KH	305	list_for_each_entry_safe(info, n, &mem_device->res_list, list) {
	306	if (info->enabled) {
	307	result = remove_memory(info->start_addr, info->length);
	308	if (result)
	309	return result;
	310	}
	311	kfree(info);
1da177e4 LT	312	}
	313
	314	/* Power-off and eject the device */
	315	result = acpi_memory_powerdown_device(mem_device);
	316	if (result) {
1da177e4 LT	317	/* Set the status of the device to invalid */
	318	mem_device->state = MEMORY_INVALID_STATE;
	319	return result;
	320	}
	321
	322	mem_device->state = MEMORY_POWER_OFF_STATE;
	323	return result;
	324	}
	325
4be44fcd	326	static void acpi_memory_device_notify(acpi_handle handle, u32 event, void *data)
1da177e4 LT	327	{
	328	struct acpi_memory_device *mem_device;
	329	struct acpi_device *device;
	330
1da177e4 LT	331
	332	switch (event) {
	333	case ACPI_NOTIFY_BUS_CHECK:
	334	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
4be44fcd	335	"\nReceived BUS CHECK notification for device\n"));
1da177e4 LT	336	/* Fall Through */
	337	case ACPI_NOTIFY_DEVICE_CHECK:
	338	if (event == ACPI_NOTIFY_DEVICE_CHECK)
	339	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
4be44fcd	340	"\nReceived DEVICE CHECK notification for device\n"));
1da177e4	341	if (acpi_memory_get_device(handle, &mem_device)) {
6468463a	342	printk(KERN_ERR PREFIX "Cannot find driver data\n");
d550d98d	343	return;
1da177e4 LT	344	}
	345
	346	if (!acpi_memory_check_device(mem_device)) {
	347	if (acpi_memory_enable_device(mem_device))
6468463a LB	348	printk(KERN_ERR PREFIX
6468463a LB	349	"Cannot enable memory device\n");
1da177e4 LT	350	}
	351	break;
	352	case ACPI_NOTIFY_EJECT_REQUEST:
	353	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
4be44fcd	354	"\nReceived EJECT REQUEST notification for device\n"));
1da177e4 LT	355
1da177e4 LT	356	if (acpi_bus_get_device(handle, &device)) {
6468463a	357	printk(KERN_ERR PREFIX "Device doesn't exist\n");
1da177e4 LT	358	break;
	359	}
	360	mem_device = acpi_driver_data(device);
	361	if (!mem_device) {
6468463a	362	printk(KERN_ERR PREFIX "Driver Data is NULL\n");
1da177e4 LT	363	break;
	364	}
	365
	366	/*
	367	* Currently disabling memory device from kernel mode
	368	* TBD: Can also be disabled from user mode scripts
	369	* TBD: Can also be disabled by Callback registration
4be44fcd	370	* with generic sysfs driver
1da177e4 LT	371	*/
1da177e4 LT	372	if (acpi_memory_disable_device(mem_device))
6468463a LB	373	printk(KERN_ERR PREFIX
6468463a LB	374	"Disable memory device\n");
1da177e4 LT	375	/*
	376	* TBD: Invoke acpi_bus_remove to cleanup data structures
	377	*/
	378	break;
	379	default:
	380	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
4be44fcd	381	"Unsupported event [0x%x]\n", event));
1da177e4 LT	382	break;
	383	}
	384
d550d98d	385	return;
1da177e4 LT	386	}
1da177e4 LT	387
4be44fcd	388	static int acpi_memory_device_add(struct acpi_device *device)
1da177e4 LT	389	{
	390	int result;
	391	struct acpi_memory_device *mem_device = NULL;
	392
1da177e4 LT	393
1da177e4 LT	394	if (!device)
d550d98d	395	return -EINVAL;
1da177e4	396
36bcbec7	397	mem_device = kzalloc(sizeof(struct acpi_memory_device), GFP_KERNEL);
1da177e4	398	if (!mem_device)
d550d98d	399	return -ENOMEM;
1da177e4	400
9ac02398	401	INIT_LIST_HEAD(&mem_device->res_list);
3b74863d	402	mem_device->device = device;
1da177e4 LT	403	sprintf(acpi_device_name(device), "%s", ACPI_MEMORY_DEVICE_NAME);
	404	sprintf(acpi_device_class(device), "%s", ACPI_MEMORY_DEVICE_CLASS);
	405	acpi_driver_data(device) = mem_device;
	406
	407	/* Get the range from the _CRS */
	408	result = acpi_memory_get_device_resources(mem_device);
	409	if (result) {
	410	kfree(mem_device);
d550d98d	411	return result;
1da177e4 LT	412	}
	413
	414	/* Set the device state */
	415	mem_device->state = MEMORY_POWER_ON_STATE;
	416
6cbe44cd	417	printk(KERN_DEBUG "%s \n", acpi_device_name(device));
1da177e4	418
d550d98d	419	return result;
1da177e4 LT	420	}
1da177e4 LT	421
4be44fcd	422	static int acpi_memory_device_remove(struct acpi_device *device, int type)
1da177e4 LT	423	{
	424	struct acpi_memory_device *mem_device = NULL;
	425
1da177e4 LT	426
1da177e4 LT	427	if (!device \|\| !acpi_driver_data(device))
d550d98d	428	return -EINVAL;
1da177e4	429
50dd0969	430	mem_device = acpi_driver_data(device);
1da177e4 LT	431	kfree(mem_device);
1da177e4 LT	432
d550d98d	433	return 0;
1da177e4 LT	434	}
1da177e4 LT	435
1f425994 YG	436	static int acpi_memory_device_start (struct acpi_device *device)
	437	{
	438	struct acpi_memory_device *mem_device;
	439	int result = 0;
	440
887b9593 YG	441	/*
	442	* Early boot code has recognized memory area by EFI/E820.
	443	* If DSDT shows these memory devices on boot, hotplug is not necessary
	444	* for them. So, it just returns until completion of this driver's
	445	* start up.
	446	*/
	447	if (!acpi_hotmem_initialized)
	448	return 0;
	449
1f425994 YG	450	mem_device = acpi_driver_data(device);
	451
	452	if (!acpi_memory_check_device(mem_device)) {
	453	/* call add_memory func */
	454	result = acpi_memory_enable_device(mem_device);
	455	if (result)
	456	ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
	457	"Error in acpi_memory_enable_device\n"));
	458	}
d120cfb5	459	return result;
1f425994 YG	460	}
1f425994 YG	461
1da177e4 LT	462	/*
	463	* Helper function to check for memory device
	464	*/
4be44fcd	465	static acpi_status is_memory_device(acpi_handle handle)
1da177e4 LT	466	{
	467	char *hardware_id;
	468	acpi_status status;
4be44fcd	469	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1da177e4 LT	470	struct acpi_device_info *info;
1da177e4 LT	471
1da177e4 LT	472
	473	status = acpi_get_object_info(handle, &buffer);
	474	if (ACPI_FAILURE(status))
d550d98d	475	return status;
1da177e4 LT	476
	477	info = buffer.pointer;
	478	if (!(info->valid & ACPI_VALID_HID)) {
02438d87	479	kfree(buffer.pointer);
d550d98d	480	return AE_ERROR;
1da177e4 LT	481	}
	482
	483	hardware_id = info->hardware_id.value;
	484	if ((hardware_id == NULL) \|\|
4be44fcd	485	(strcmp(hardware_id, ACPI_MEMORY_DEVICE_HID)))
1da177e4 LT	486	status = AE_ERROR;
1da177e4 LT	487
02438d87	488	kfree(buffer.pointer);
d550d98d	489	return status;
1da177e4 LT	490	}
	491
	492	static acpi_status
4be44fcd LB	493	acpi_memory_register_notify_handler(acpi_handle handle,
4be44fcd LB	494	u32 level, void ctxt, void *retv)
1da177e4 LT	495	{
	496	acpi_status status;
	497
1da177e4 LT	498
1da177e4 LT	499	status = is_memory_device(handle);
07dd4855	500	if (ACPI_FAILURE(status))
d550d98d	501	return AE_OK; /* continue */
1da177e4 LT	502
1da177e4 LT	503	status = acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
4be44fcd	504	acpi_memory_device_notify, NULL);
a6fc6720	505	/* continue */
d550d98d	506	return AE_OK;
1da177e4 LT	507	}
	508
	509	static acpi_status
4be44fcd LB	510	acpi_memory_deregister_notify_handler(acpi_handle handle,
4be44fcd LB	511	u32 level, void ctxt, void *retv)
1da177e4 LT	512	{
	513	acpi_status status;
	514
1da177e4 LT	515
1da177e4 LT	516	status = is_memory_device(handle);
07dd4855	517	if (ACPI_FAILURE(status))
d550d98d	518	return AE_OK; /* continue */
1da177e4 LT	519
1da177e4 LT	520	status = acpi_remove_notify_handler(handle,
4be44fcd LB	521	ACPI_SYSTEM_NOTIFY,
4be44fcd LB	522	acpi_memory_device_notify);
1da177e4	523
d550d98d	524	return AE_OK; /* continue */
1da177e4 LT	525	}
1da177e4 LT	526
4be44fcd	527	static int __init acpi_memory_device_init(void)
1da177e4 LT	528	{
	529	int result;
	530	acpi_status status;
	531
1da177e4 LT	532
	533	result = acpi_bus_register_driver(&acpi_memory_device_driver);
	534
	535	if (result < 0)
d550d98d	536	return -ENODEV;
1da177e4 LT	537
1da177e4 LT	538	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
4be44fcd LB	539	ACPI_UINT32_MAX,
	540	acpi_memory_register_notify_handler,
	541	NULL, NULL);
1da177e4	542
4be44fcd	543	if (ACPI_FAILURE(status)) {
a6fc6720	544	ACPI_EXCEPTION((AE_INFO, status, "walk_namespace failed"));
1da177e4	545	acpi_bus_unregister_driver(&acpi_memory_device_driver);
d550d98d	546	return -ENODEV;
4be44fcd	547	}
1da177e4	548
887b9593	549	acpi_hotmem_initialized = 1;
d550d98d	550	return 0;
1da177e4 LT	551	}
1da177e4 LT	552
4be44fcd	553	static void __exit acpi_memory_device_exit(void)
1da177e4 LT	554	{
	555	acpi_status status;
	556
1da177e4 LT	557
	558	/*
	559	* Adding this to un-install notification handlers for all the device
	560	* handles.
	561	*/
	562	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
4be44fcd LB	563	ACPI_UINT32_MAX,
	564	acpi_memory_deregister_notify_handler,
	565	NULL, NULL);
1da177e4	566
4be44fcd	567	if (ACPI_FAILURE(status))
a6fc6720	568	ACPI_EXCEPTION((AE_INFO, status, "walk_namespace failed"));
1da177e4 LT	569
	570	acpi_bus_unregister_driver(&acpi_memory_device_driver);
	571
d550d98d	572	return;
1da177e4 LT	573	}
	574
	575	module_init(acpi_memory_device_init);
	576	module_exit(acpi_memory_device_exit);