linux/drivers/acpi/acpi_memhotplug.c

526 lines
14 KiB
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_DRIVER_NAME "Hotplug Mem Driver"
#define ACPI_MEMORY_DEVICE_NAME "Hotplug Mem Device"
#define _COMPONENT ACPI_MEMORY_DEVICE_COMPONENT
ACPI_MODULE_NAME("acpi_memory")
MODULE_AUTHOR("Naveen B S <naveen.b.s@intel.com>");
MODULE_DESCRIPTION(ACPI_MEMORY_DEVICE_DRIVER_NAME);
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 struct acpi_driver acpi_memory_device_driver = {
.name = ACPI_MEMORY_DEVICE_DRIVER_NAME,
.class = ACPI_MEMORY_DEVICE_CLASS,
.ids = ACPI_MEMORY_DEVICE_HID,
.ops = {
.add = acpi_memory_device_add,
.remove = acpi_memory_device_remove,
},
};
struct acpi_memory_device {
acpi_handle handle;
unsigned int state; /* State of the memory device */
unsigned short cache_attribute; /* memory cache attribute */
unsigned short read_write_attribute; /* memory read/write attribute */
u64 start_addr; /* Memory Range start physical addr */
u64 end_addr; /* Memory Range end physical addr */
};
static int
acpi_memory_get_device_resources(struct acpi_memory_device *mem_device)
{
acpi_status status;
struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
struct acpi_resource *resource = NULL;
struct acpi_resource_address64 address64;
ACPI_FUNCTION_TRACE("acpi_memory_get_device_resources");
/* Get the range from the _CRS */
status = acpi_get_current_resources(mem_device->handle, &buffer);
if (ACPI_FAILURE(status))
return_VALUE(-EINVAL);
resource = (struct acpi_resource *)buffer.pointer;
status = acpi_resource_to_address64(resource, &address64);
if (ACPI_SUCCESS(status)) {
if (address64.resource_type == ACPI_MEMORY_RANGE) {
/* Populate the structure */
mem_device->cache_attribute =
address64.attribute.memory.cache_attribute;
mem_device->read_write_attribute =
address64.attribute.memory.read_write_attribute;
mem_device->start_addr = address64.min_address_range;
mem_device->end_addr = address64.max_address_range;
}
}
acpi_os_free(buffer.pointer);
return_VALUE(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;
ACPI_FUNCTION_TRACE("acpi_memory_get_device");
if (!acpi_bus_get_device(handle, &device) && device)
goto end;
status = acpi_get_parent(handle, &phandle);
if (ACPI_FAILURE(status)) {
ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error in acpi_get_parent\n"));
return_VALUE(-EINVAL);
}
/* Get the parent device */
status = acpi_bus_get_device(phandle, &pdevice);
if (ACPI_FAILURE(status)) {
ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
"Error in acpi_bus_get_device\n"));
return_VALUE(-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_DEBUG_PRINT((ACPI_DB_ERROR, "Error in acpi_bus_add\n"));
return_VALUE(-EINVAL);
}
end:
*mem_device = acpi_driver_data(device);
if (!(*mem_device)) {
printk(KERN_ERR "\n driver data not found");
return_VALUE(-ENODEV);
}
return_VALUE(0);
}
static int acpi_memory_check_device(struct acpi_memory_device *mem_device)
{
unsigned long current_status;
ACPI_FUNCTION_TRACE("acpi_memory_check_device");
/* Get device present/absent information from the _STA */
if (ACPI_FAILURE(acpi_evaluate_integer(mem_device->handle, "_STA",
NULL, &current_status)))
return_VALUE(-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_VALUE(-ENODEV);
return_VALUE(0);
}
static int acpi_memory_enable_device(struct acpi_memory_device *mem_device)
{
int result;
ACPI_FUNCTION_TRACE("acpi_memory_enable_device");
/* Get the range from the _CRS */
result = acpi_memory_get_device_resources(mem_device);
if (result) {
ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
"\nget_device_resources failed\n"));
mem_device->state = MEMORY_INVALID_STATE;
return result;
}
/*
* Tell the VM there is more memory here...
* Note: Assume that this function returns zero on success
*/
result = add_memory(mem_device->start_addr,
(mem_device->end_addr - mem_device->start_addr) + 1);
if (result) {
ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "\nadd_memory failed\n"));
mem_device->state = MEMORY_INVALID_STATE;
return result;
}
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;
ACPI_FUNCTION_TRACE("acpi_memory_powerdown_device");
/* 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->handle,
"_EJ0", &arg_list, NULL);
/* Return on _EJ0 failure */
if (ACPI_FAILURE(status)) {
ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "_EJ0 failed.\n"));
return_VALUE(-ENODEV);
}
/* Evalute _STA to check if the device is disabled */
status = acpi_evaluate_integer(mem_device->handle, "_STA",
NULL, &current_status);
if (ACPI_FAILURE(status))
return_VALUE(-ENODEV);
/* Check for device status. Device should be disabled */
if (current_status & ACPI_MEMORY_STA_ENABLED)
return_VALUE(-EINVAL);
return_VALUE(0);
}
static int acpi_memory_disable_device(struct acpi_memory_device *mem_device)
{
int result;
u64 start = mem_device->start_addr;
u64 len = mem_device->end_addr - start + 1;
unsigned long attr = mem_device->read_write_attribute;
ACPI_FUNCTION_TRACE("acpi_memory_disable_device");
/*
* Ask the VM to offline this memory range.
* Note: Assume that this function returns zero on success
*/
result = remove_memory(start, len);
if (result) {
ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Hot-Remove failed.\n"));
return_VALUE(result);
}
/* Power-off and eject the device */
result = acpi_memory_powerdown_device(mem_device);
if (result) {
ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
"Device Power Down failed.\n"));
/* 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;
ACPI_FUNCTION_TRACE("acpi_memory_device_notify");
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)) {
ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
"Error in finding driver data\n"));
return_VOID;
}
if (!acpi_memory_check_device(mem_device)) {
if (acpi_memory_enable_device(mem_device))
ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
"Error in acpi_memory_enable_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)) {
ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
"Device doesn't exist\n"));
break;
}
mem_device = acpi_driver_data(device);
if (!mem_device) {
ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
"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))
ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
"Error in acpi_memory_disable_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_VOID;
}
static int acpi_memory_device_add(struct acpi_device *device)
{
int result;
struct acpi_memory_device *mem_device = NULL;
ACPI_FUNCTION_TRACE("acpi_memory_device_add");
if (!device)
return_VALUE(-EINVAL);
mem_device = kmalloc(sizeof(struct acpi_memory_device), GFP_KERNEL);
if (!mem_device)
return_VALUE(-ENOMEM);
memset(mem_device, 0, sizeof(struct acpi_memory_device));
mem_device->handle = device->handle;
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_VALUE(result);
}
/* Set the device state */
mem_device->state = MEMORY_POWER_ON_STATE;
printk(KERN_INFO "%s \n", acpi_device_name(device));
return_VALUE(result);
}
static int acpi_memory_device_remove(struct acpi_device *device, int type)
{
struct acpi_memory_device *mem_device = NULL;
ACPI_FUNCTION_TRACE("acpi_memory_device_remove");
if (!device || !acpi_driver_data(device))
return_VALUE(-EINVAL);
mem_device = (struct acpi_memory_device *)acpi_driver_data(device);
kfree(mem_device);
return_VALUE(0);
}
/*
* 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;
ACPI_FUNCTION_TRACE("is_memory_device");
status = acpi_get_object_info(handle, &buffer);
if (ACPI_FAILURE(status))
return_ACPI_STATUS(AE_ERROR);
info = buffer.pointer;
if (!(info->valid & ACPI_VALID_HID)) {
acpi_os_free(buffer.pointer);
return_ACPI_STATUS(AE_ERROR);
}
hardware_id = info->hardware_id.value;
if ((hardware_id == NULL) ||
(strcmp(hardware_id, ACPI_MEMORY_DEVICE_HID)))
status = AE_ERROR;
acpi_os_free(buffer.pointer);
return_ACPI_STATUS(status);
}
static acpi_status
acpi_memory_register_notify_handler(acpi_handle handle,
u32 level, void *ctxt, void **retv)
{
acpi_status status;
ACPI_FUNCTION_TRACE("acpi_memory_register_notify_handler");
status = is_memory_device(handle);
if (ACPI_FAILURE(status))
return_ACPI_STATUS(AE_OK); /* continue */
status = acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
acpi_memory_device_notify, NULL);
if (ACPI_FAILURE(status)) {
ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
"Error installing notify handler\n"));
return_ACPI_STATUS(AE_OK); /* continue */
}
return_ACPI_STATUS(status);
}
static acpi_status
acpi_memory_deregister_notify_handler(acpi_handle handle,
u32 level, void *ctxt, void **retv)
{
acpi_status status;
ACPI_FUNCTION_TRACE("acpi_memory_deregister_notify_handler");
status = is_memory_device(handle);
if (ACPI_FAILURE(status))
return_ACPI_STATUS(AE_OK); /* continue */
status = acpi_remove_notify_handler(handle,
ACPI_SYSTEM_NOTIFY,
acpi_memory_device_notify);
if (ACPI_FAILURE(status)) {
ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
"Error removing notify handler\n"));
return_ACPI_STATUS(AE_OK); /* continue */
}
return_ACPI_STATUS(status);
}
static int __init acpi_memory_device_init(void)
{
int result;
acpi_status status;
ACPI_FUNCTION_TRACE("acpi_memory_device_init");
result = acpi_bus_register_driver(&acpi_memory_device_driver);
if (result < 0)
return_VALUE(-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_DEBUG_PRINT((ACPI_DB_ERROR, "walk_namespace failed\n"));
acpi_bus_unregister_driver(&acpi_memory_device_driver);
return_VALUE(-ENODEV);
}
return_VALUE(0);
}
static void __exit acpi_memory_device_exit(void)
{
acpi_status status;
ACPI_FUNCTION_TRACE("acpi_memory_device_exit");
/*
* 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_DEBUG_PRINT((ACPI_DB_ERROR, "walk_namespace failed\n"));
acpi_bus_unregister_driver(&acpi_memory_device_driver);
return_VOID;
}
module_init(acpi_memory_device_init);
module_exit(acpi_memory_device_exit);