2 * Copyright (C) 2004 Intel Corporation <naveen.b.s@intel.com>
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.
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
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.
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
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>
35 #define ACPI_MEMORY_DEVICE_COMPONENT 0x08000000UL
36 #define ACPI_MEMORY_DEVICE_CLASS "memory"
37 #define ACPI_MEMORY_DEVICE_HID "PNP0C80"
38 #define ACPI_MEMORY_DEVICE_DRIVER_NAME "Hotplug Mem Driver"
39 #define ACPI_MEMORY_DEVICE_NAME "Hotplug Mem Device"
41 #define _COMPONENT ACPI_MEMORY_DEVICE_COMPONENT
43 ACPI_MODULE_NAME("acpi_memory")
44 MODULE_AUTHOR("Naveen B S <naveen.b.s@intel.com>");
45 MODULE_DESCRIPTION(ACPI_MEMORY_DEVICE_DRIVER_NAME
);
46 MODULE_LICENSE("GPL");
48 /* ACPI _STA method values */
49 #define ACPI_MEMORY_STA_PRESENT (0x00000001UL)
50 #define ACPI_MEMORY_STA_ENABLED (0x00000002UL)
51 #define ACPI_MEMORY_STA_FUNCTIONAL (0x00000008UL)
53 /* Memory Device States */
54 #define MEMORY_INVALID_STATE 0
55 #define MEMORY_POWER_ON_STATE 1
56 #define MEMORY_POWER_OFF_STATE 2
58 static int acpi_memory_device_add(struct acpi_device
*device
);
59 static int acpi_memory_device_remove(struct acpi_device
*device
, int type
);
61 static struct acpi_driver acpi_memory_device_driver
= {
62 .name
= ACPI_MEMORY_DEVICE_DRIVER_NAME
,
63 .class = ACPI_MEMORY_DEVICE_CLASS
,
64 .ids
= ACPI_MEMORY_DEVICE_HID
,
66 .add
= acpi_memory_device_add
,
67 .remove
= acpi_memory_device_remove
,
71 struct acpi_memory_device
{
73 unsigned int state
; /* State of the memory device */
74 unsigned short cache_attribute
; /* memory cache attribute */
75 unsigned short read_write_attribute
; /* memory read/write attribute */
76 u64 start_addr
; /* Memory Range start physical addr */
77 u64 end_addr
; /* Memory Range end physical addr */
81 acpi_memory_get_device_resources(struct acpi_memory_device
*mem_device
)
84 struct acpi_buffer buffer
= { ACPI_ALLOCATE_BUFFER
, NULL
};
85 struct acpi_resource
*resource
= NULL
;
86 struct acpi_resource_address64 address64
;
88 ACPI_FUNCTION_TRACE("acpi_memory_get_device_resources");
90 /* Get the range from the _CRS */
91 status
= acpi_get_current_resources(mem_device
->handle
, &buffer
);
92 if (ACPI_FAILURE(status
))
93 return_VALUE(-EINVAL
);
95 resource
= (struct acpi_resource
*)buffer
.pointer
;
96 status
= acpi_resource_to_address64(resource
, &address64
);
97 if (ACPI_SUCCESS(status
)) {
98 if (address64
.resource_type
== ACPI_MEMORY_RANGE
) {
99 /* Populate the structure */
100 mem_device
->cache_attribute
=
101 address64
.attribute
.memory
.cache_attribute
;
102 mem_device
->read_write_attribute
=
103 address64
.attribute
.memory
.read_write_attribute
;
104 mem_device
->start_addr
= address64
.min_address_range
;
105 mem_device
->end_addr
= address64
.max_address_range
;
109 acpi_os_free(buffer
.pointer
);
114 acpi_memory_get_device(acpi_handle handle
,
115 struct acpi_memory_device
**mem_device
)
119 struct acpi_device
*device
= NULL
;
120 struct acpi_device
*pdevice
= NULL
;
122 ACPI_FUNCTION_TRACE("acpi_memory_get_device");
124 if (!acpi_bus_get_device(handle
, &device
) && device
)
127 status
= acpi_get_parent(handle
, &phandle
);
128 if (ACPI_FAILURE(status
)) {
129 ACPI_DEBUG_PRINT((ACPI_DB_ERROR
, "Error in acpi_get_parent\n"));
130 return_VALUE(-EINVAL
);
133 /* Get the parent device */
134 status
= acpi_bus_get_device(phandle
, &pdevice
);
135 if (ACPI_FAILURE(status
)) {
136 ACPI_DEBUG_PRINT((ACPI_DB_ERROR
,
137 "Error in acpi_bus_get_device\n"));
138 return_VALUE(-EINVAL
);
142 * Now add the notified device. This creates the acpi_device
143 * and invokes .add function
145 status
= acpi_bus_add(&device
, pdevice
, handle
, ACPI_BUS_TYPE_DEVICE
);
146 if (ACPI_FAILURE(status
)) {
147 ACPI_DEBUG_PRINT((ACPI_DB_ERROR
, "Error in acpi_bus_add\n"));
148 return_VALUE(-EINVAL
);
152 *mem_device
= acpi_driver_data(device
);
153 if (!(*mem_device
)) {
154 printk(KERN_ERR
"\n driver data not found");
155 return_VALUE(-ENODEV
);
161 static int acpi_memory_check_device(struct acpi_memory_device
*mem_device
)
163 unsigned long current_status
;
165 ACPI_FUNCTION_TRACE("acpi_memory_check_device");
167 /* Get device present/absent information from the _STA */
168 if (ACPI_FAILURE(acpi_evaluate_integer(mem_device
->handle
, "_STA",
169 NULL
, ¤t_status
)))
170 return_VALUE(-ENODEV
);
172 * Check for device status. Device should be
173 * present/enabled/functioning.
175 if (!((current_status
& ACPI_MEMORY_STA_PRESENT
)
176 && (current_status
& ACPI_MEMORY_STA_ENABLED
)
177 && (current_status
& ACPI_MEMORY_STA_FUNCTIONAL
)))
178 return_VALUE(-ENODEV
);
183 static int acpi_memory_enable_device(struct acpi_memory_device
*mem_device
)
187 ACPI_FUNCTION_TRACE("acpi_memory_enable_device");
189 /* Get the range from the _CRS */
190 result
= acpi_memory_get_device_resources(mem_device
);
192 ACPI_DEBUG_PRINT((ACPI_DB_ERROR
,
193 "\nget_device_resources failed\n"));
194 mem_device
->state
= MEMORY_INVALID_STATE
;
199 * Tell the VM there is more memory here...
200 * Note: Assume that this function returns zero on success
202 result
= add_memory(mem_device
->start_addr
,
203 (mem_device
->end_addr
- mem_device
->start_addr
) + 1);
205 ACPI_DEBUG_PRINT((ACPI_DB_ERROR
, "\nadd_memory failed\n"));
206 mem_device
->state
= MEMORY_INVALID_STATE
;
213 static int acpi_memory_powerdown_device(struct acpi_memory_device
*mem_device
)
216 struct acpi_object_list arg_list
;
217 union acpi_object arg
;
218 unsigned long current_status
;
220 ACPI_FUNCTION_TRACE("acpi_memory_powerdown_device");
222 /* Issue the _EJ0 command */
224 arg_list
.pointer
= &arg
;
225 arg
.type
= ACPI_TYPE_INTEGER
;
226 arg
.integer
.value
= 1;
227 status
= acpi_evaluate_object(mem_device
->handle
,
228 "_EJ0", &arg_list
, NULL
);
229 /* Return on _EJ0 failure */
230 if (ACPI_FAILURE(status
)) {
231 ACPI_DEBUG_PRINT((ACPI_DB_ERROR
, "_EJ0 failed.\n"));
232 return_VALUE(-ENODEV
);
235 /* Evalute _STA to check if the device is disabled */
236 status
= acpi_evaluate_integer(mem_device
->handle
, "_STA",
237 NULL
, ¤t_status
);
238 if (ACPI_FAILURE(status
))
239 return_VALUE(-ENODEV
);
241 /* Check for device status. Device should be disabled */
242 if (current_status
& ACPI_MEMORY_STA_ENABLED
)
243 return_VALUE(-EINVAL
);
248 static int acpi_memory_disable_device(struct acpi_memory_device
*mem_device
)
251 u64 start
= mem_device
->start_addr
;
252 u64 len
= mem_device
->end_addr
- start
+ 1;
253 unsigned long attr
= mem_device
->read_write_attribute
;
255 ACPI_FUNCTION_TRACE("acpi_memory_disable_device");
258 * Ask the VM to offline this memory range.
259 * Note: Assume that this function returns zero on success
261 result
= remove_memory(start
, len
);
263 ACPI_DEBUG_PRINT((ACPI_DB_ERROR
, "Hot-Remove failed.\n"));
264 return_VALUE(result
);
267 /* Power-off and eject the device */
268 result
= acpi_memory_powerdown_device(mem_device
);
270 ACPI_DEBUG_PRINT((ACPI_DB_ERROR
,
271 "Device Power Down failed.\n"));
272 /* Set the status of the device to invalid */
273 mem_device
->state
= MEMORY_INVALID_STATE
;
277 mem_device
->state
= MEMORY_POWER_OFF_STATE
;
281 static void acpi_memory_device_notify(acpi_handle handle
, u32 event
, void *data
)
283 struct acpi_memory_device
*mem_device
;
284 struct acpi_device
*device
;
286 ACPI_FUNCTION_TRACE("acpi_memory_device_notify");
289 case ACPI_NOTIFY_BUS_CHECK
:
290 ACPI_DEBUG_PRINT((ACPI_DB_INFO
,
291 "\nReceived BUS CHECK notification for device\n"));
293 case ACPI_NOTIFY_DEVICE_CHECK
:
294 if (event
== ACPI_NOTIFY_DEVICE_CHECK
)
295 ACPI_DEBUG_PRINT((ACPI_DB_INFO
,
296 "\nReceived DEVICE CHECK notification for device\n"));
297 if (acpi_memory_get_device(handle
, &mem_device
)) {
298 ACPI_DEBUG_PRINT((ACPI_DB_ERROR
,
299 "Error in finding driver data\n"));
303 if (!acpi_memory_check_device(mem_device
)) {
304 if (acpi_memory_enable_device(mem_device
))
305 ACPI_DEBUG_PRINT((ACPI_DB_ERROR
,
306 "Error in acpi_memory_enable_device\n"));
309 case ACPI_NOTIFY_EJECT_REQUEST
:
310 ACPI_DEBUG_PRINT((ACPI_DB_INFO
,
311 "\nReceived EJECT REQUEST notification for device\n"));
313 if (acpi_bus_get_device(handle
, &device
)) {
314 ACPI_DEBUG_PRINT((ACPI_DB_ERROR
,
315 "Device doesn't exist\n"));
318 mem_device
= acpi_driver_data(device
);
320 ACPI_DEBUG_PRINT((ACPI_DB_ERROR
,
321 "Driver Data is NULL\n"));
326 * Currently disabling memory device from kernel mode
327 * TBD: Can also be disabled from user mode scripts
328 * TBD: Can also be disabled by Callback registration
329 * with generic sysfs driver
331 if (acpi_memory_disable_device(mem_device
))
332 ACPI_DEBUG_PRINT((ACPI_DB_ERROR
,
333 "Error in acpi_memory_disable_device\n"));
335 * TBD: Invoke acpi_bus_remove to cleanup data structures
339 ACPI_DEBUG_PRINT((ACPI_DB_INFO
,
340 "Unsupported event [0x%x]\n", event
));
347 static int acpi_memory_device_add(struct acpi_device
*device
)
350 struct acpi_memory_device
*mem_device
= NULL
;
352 ACPI_FUNCTION_TRACE("acpi_memory_device_add");
355 return_VALUE(-EINVAL
);
357 mem_device
= kmalloc(sizeof(struct acpi_memory_device
), GFP_KERNEL
);
359 return_VALUE(-ENOMEM
);
360 memset(mem_device
, 0, sizeof(struct acpi_memory_device
));
362 mem_device
->handle
= device
->handle
;
363 sprintf(acpi_device_name(device
), "%s", ACPI_MEMORY_DEVICE_NAME
);
364 sprintf(acpi_device_class(device
), "%s", ACPI_MEMORY_DEVICE_CLASS
);
365 acpi_driver_data(device
) = mem_device
;
367 /* Get the range from the _CRS */
368 result
= acpi_memory_get_device_resources(mem_device
);
371 return_VALUE(result
);
374 /* Set the device state */
375 mem_device
->state
= MEMORY_POWER_ON_STATE
;
377 printk(KERN_INFO
"%s \n", acpi_device_name(device
));
379 return_VALUE(result
);
382 static int acpi_memory_device_remove(struct acpi_device
*device
, int type
)
384 struct acpi_memory_device
*mem_device
= NULL
;
386 ACPI_FUNCTION_TRACE("acpi_memory_device_remove");
388 if (!device
|| !acpi_driver_data(device
))
389 return_VALUE(-EINVAL
);
391 mem_device
= (struct acpi_memory_device
*)acpi_driver_data(device
);
398 * Helper function to check for memory device
400 static acpi_status
is_memory_device(acpi_handle handle
)
404 struct acpi_buffer buffer
= { ACPI_ALLOCATE_BUFFER
, NULL
};
405 struct acpi_device_info
*info
;
407 ACPI_FUNCTION_TRACE("is_memory_device");
409 status
= acpi_get_object_info(handle
, &buffer
);
410 if (ACPI_FAILURE(status
))
411 return_ACPI_STATUS(AE_ERROR
);
413 info
= buffer
.pointer
;
414 if (!(info
->valid
& ACPI_VALID_HID
)) {
415 acpi_os_free(buffer
.pointer
);
416 return_ACPI_STATUS(AE_ERROR
);
419 hardware_id
= info
->hardware_id
.value
;
420 if ((hardware_id
== NULL
) ||
421 (strcmp(hardware_id
, ACPI_MEMORY_DEVICE_HID
)))
424 acpi_os_free(buffer
.pointer
);
425 return_ACPI_STATUS(status
);
429 acpi_memory_register_notify_handler(acpi_handle handle
,
430 u32 level
, void *ctxt
, void **retv
)
434 ACPI_FUNCTION_TRACE("acpi_memory_register_notify_handler");
436 status
= is_memory_device(handle
);
437 if (ACPI_FAILURE(status
))
438 return_ACPI_STATUS(AE_OK
); /* continue */
440 status
= acpi_install_notify_handler(handle
, ACPI_SYSTEM_NOTIFY
,
441 acpi_memory_device_notify
, NULL
);
442 if (ACPI_FAILURE(status
)) {
443 ACPI_DEBUG_PRINT((ACPI_DB_ERROR
,
444 "Error installing notify handler\n"));
445 return_ACPI_STATUS(AE_OK
); /* continue */
448 return_ACPI_STATUS(status
);
452 acpi_memory_deregister_notify_handler(acpi_handle handle
,
453 u32 level
, void *ctxt
, void **retv
)
457 ACPI_FUNCTION_TRACE("acpi_memory_deregister_notify_handler");
459 status
= is_memory_device(handle
);
460 if (ACPI_FAILURE(status
))
461 return_ACPI_STATUS(AE_OK
); /* continue */
463 status
= acpi_remove_notify_handler(handle
,
465 acpi_memory_device_notify
);
466 if (ACPI_FAILURE(status
)) {
467 ACPI_DEBUG_PRINT((ACPI_DB_ERROR
,
468 "Error removing notify handler\n"));
469 return_ACPI_STATUS(AE_OK
); /* continue */
472 return_ACPI_STATUS(status
);
475 static int __init
acpi_memory_device_init(void)
480 ACPI_FUNCTION_TRACE("acpi_memory_device_init");
482 result
= acpi_bus_register_driver(&acpi_memory_device_driver
);
485 return_VALUE(-ENODEV
);
487 status
= acpi_walk_namespace(ACPI_TYPE_DEVICE
, ACPI_ROOT_OBJECT
,
489 acpi_memory_register_notify_handler
,
492 if (ACPI_FAILURE(status
)) {
493 ACPI_DEBUG_PRINT((ACPI_DB_ERROR
, "walk_namespace failed\n"));
494 acpi_bus_unregister_driver(&acpi_memory_device_driver
);
495 return_VALUE(-ENODEV
);
501 static void __exit
acpi_memory_device_exit(void)
505 ACPI_FUNCTION_TRACE("acpi_memory_device_exit");
508 * Adding this to un-install notification handlers for all the device
511 status
= acpi_walk_namespace(ACPI_TYPE_DEVICE
, ACPI_ROOT_OBJECT
,
513 acpi_memory_deregister_notify_handler
,
516 if (ACPI_FAILURE(status
))
517 ACPI_DEBUG_PRINT((ACPI_DB_ERROR
, "walk_namespace failed\n"));
519 acpi_bus_unregister_driver(&acpi_memory_device_driver
);
524 module_init(acpi_memory_device_init
);
525 module_exit(acpi_memory_device_exit
);