diff options
Diffstat (limited to 'drivers/acpi/acpi_memhotplug.c')
| -rw-r--r-- | drivers/acpi/acpi_memhotplug.c | 542 |
1 files changed, 542 insertions, 0 deletions
diff --git a/drivers/acpi/acpi_memhotplug.c b/drivers/acpi/acpi_memhotplug.c new file mode 100644 index 000000000000..77285ffe41c5 --- /dev/null +++ b/drivers/acpi/acpi_memhotplug.c @@ -0,0 +1,542 @@ +/* + * 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, ¤t_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, + mem_device->read_write_attribute); + 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, ¤t_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, attr); + 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); + + |