Pull acpi_device_handle_cleanup into release branch
[linux-2.6.git] / drivers / acpi / acpi_memhotplug.c
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
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"
40
41 #define _COMPONENT              ACPI_MEMORY_DEVICE_COMPONENT
42
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");
47
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)
52
53 /* Memory Device States */
54 #define MEMORY_INVALID_STATE    0
55 #define MEMORY_POWER_ON_STATE   1
56 #define MEMORY_POWER_OFF_STATE  2
57
58 static int acpi_memory_device_add(struct acpi_device *device);
59 static int acpi_memory_device_remove(struct acpi_device *device, int type);
60 static int acpi_memory_device_start(struct acpi_device *device);
61
62 static struct acpi_driver acpi_memory_device_driver = {
63         .name = ACPI_MEMORY_DEVICE_DRIVER_NAME,
64         .class = ACPI_MEMORY_DEVICE_CLASS,
65         .ids = ACPI_MEMORY_DEVICE_HID,
66         .ops = {
67                 .add = acpi_memory_device_add,
68                 .remove = acpi_memory_device_remove,
69                 .start = acpi_memory_device_start,
70                 },
71 };
72
73 struct acpi_memory_info {
74         struct list_head list;
75         u64 start_addr;         /* Memory Range start physical addr */
76         u64 length;             /* Memory Range length */
77         unsigned short caching; /* memory cache attribute */
78         unsigned short write_protect;   /* memory read/write attribute */
79         unsigned int enabled:1;
80 };
81
82 struct acpi_memory_device {
83         struct acpi_device * device;
84         unsigned int state;     /* State of the memory device */
85         struct list_head res_list;
86 };
87
88 static acpi_status
89 acpi_memory_get_resource(struct acpi_resource *resource, void *context)
90 {
91         struct acpi_memory_device *mem_device = context;
92         struct acpi_resource_address64 address64;
93         struct acpi_memory_info *info, *new;
94         acpi_status status;
95
96         status = acpi_resource_to_address64(resource, &address64);
97         if (ACPI_FAILURE(status) ||
98             (address64.resource_type != ACPI_MEMORY_RANGE))
99                 return AE_OK;
100
101         list_for_each_entry(info, &mem_device->res_list, list) {
102                 /* Can we combine the resource range information? */
103                 if ((info->caching == address64.info.mem.caching) &&
104                     (info->write_protect == address64.info.mem.write_protect) &&
105                     (info->start_addr + info->length == address64.minimum)) {
106                         info->length += address64.address_length;
107                         return AE_OK;
108                 }
109         }
110
111         new = kzalloc(sizeof(struct acpi_memory_info), GFP_KERNEL);
112         if (!new)
113                 return AE_ERROR;
114
115         INIT_LIST_HEAD(&new->list);
116         new->caching = address64.info.mem.caching;
117         new->write_protect = address64.info.mem.write_protect;
118         new->start_addr = address64.minimum;
119         new->length = address64.address_length;
120         list_add_tail(&new->list, &mem_device->res_list);
121
122         return AE_OK;
123 }
124
125 static int
126 acpi_memory_get_device_resources(struct acpi_memory_device *mem_device)
127 {
128         acpi_status status;
129         struct acpi_memory_info *info, *n;
130
131
132         status = acpi_walk_resources(mem_device->device->handle, METHOD_NAME__CRS,
133                                      acpi_memory_get_resource, mem_device);
134         if (ACPI_FAILURE(status)) {
135                 list_for_each_entry_safe(info, n, &mem_device->res_list, list)
136                         kfree(info);
137                 return -EINVAL;
138         }
139
140         return 0;
141 }
142
143 static int
144 acpi_memory_get_device(acpi_handle handle,
145                        struct acpi_memory_device **mem_device)
146 {
147         acpi_status status;
148         acpi_handle phandle;
149         struct acpi_device *device = NULL;
150         struct acpi_device *pdevice = NULL;
151
152
153         if (!acpi_bus_get_device(handle, &device) && device)
154                 goto end;
155
156         status = acpi_get_parent(handle, &phandle);
157         if (ACPI_FAILURE(status)) {
158                 ACPI_EXCEPTION((AE_INFO, status, "Cannot find acpi parent"));
159                 return -EINVAL;
160         }
161
162         /* Get the parent device */
163         status = acpi_bus_get_device(phandle, &pdevice);
164         if (ACPI_FAILURE(status)) {
165                 ACPI_EXCEPTION((AE_INFO, status, "Cannot get acpi bus device"));
166                 return -EINVAL;
167         }
168
169         /*
170          * Now add the notified device.  This creates the acpi_device
171          * and invokes .add function
172          */
173         status = acpi_bus_add(&device, pdevice, handle, ACPI_BUS_TYPE_DEVICE);
174         if (ACPI_FAILURE(status)) {
175                 ACPI_EXCEPTION((AE_INFO, status, "Cannot add acpi bus"));
176                 return -EINVAL;
177         }
178
179       end:
180         *mem_device = acpi_driver_data(device);
181         if (!(*mem_device)) {
182                 printk(KERN_ERR "\n driver data not found");
183                 return -ENODEV;
184         }
185
186         return 0;
187 }
188
189 static int acpi_memory_check_device(struct acpi_memory_device *mem_device)
190 {
191         unsigned long current_status;
192
193
194         /* Get device present/absent information from the _STA */
195         if (ACPI_FAILURE(acpi_evaluate_integer(mem_device->device->handle, "_STA",
196                                                NULL, &current_status)))
197                 return -ENODEV;
198         /*
199          * Check for device status. Device should be
200          * present/enabled/functioning.
201          */
202         if (!((current_status & ACPI_MEMORY_STA_PRESENT)
203               && (current_status & ACPI_MEMORY_STA_ENABLED)
204               && (current_status & ACPI_MEMORY_STA_FUNCTIONAL)))
205                 return -ENODEV;
206
207         return 0;
208 }
209
210 static int acpi_memory_enable_device(struct acpi_memory_device *mem_device)
211 {
212         int result, num_enabled = 0;
213         struct acpi_memory_info *info;
214         int node;
215
216
217         /* Get the range from the _CRS */
218         result = acpi_memory_get_device_resources(mem_device);
219         if (result) {
220                 printk(KERN_ERR PREFIX "get_device_resources failed\n");
221                 mem_device->state = MEMORY_INVALID_STATE;
222                 return result;
223         }
224
225         node = acpi_get_node(mem_device->device->handle);
226         /*
227          * Tell the VM there is more memory here...
228          * Note: Assume that this function returns zero on success
229          * We don't have memory-hot-add rollback function,now.
230          * (i.e. memory-hot-remove function)
231          */
232         list_for_each_entry(info, &mem_device->res_list, list) {
233                 u64 start_pfn, end_pfn;
234
235                 start_pfn = info->start_addr >> PAGE_SHIFT;
236                 end_pfn = (info->start_addr + info->length - 1) >> PAGE_SHIFT;
237
238                 if (pfn_valid(start_pfn) || pfn_valid(end_pfn)) {
239                         /* already enabled. try next area */
240                         num_enabled++;
241                         continue;
242                 }
243
244                 result = add_memory(node, info->start_addr, info->length);
245                 if (result)
246                         continue;
247                 info->enabled = 1;
248                 num_enabled++;
249         }
250         if (!num_enabled) {
251                 printk(KERN_ERR PREFIX "add_memory failed\n");
252                 mem_device->state = MEMORY_INVALID_STATE;
253                 return -EINVAL;
254         }
255
256         return result;
257 }
258
259 static int acpi_memory_powerdown_device(struct acpi_memory_device *mem_device)
260 {
261         acpi_status status;
262         struct acpi_object_list arg_list;
263         union acpi_object arg;
264         unsigned long current_status;
265
266
267         /* Issue the _EJ0 command */
268         arg_list.count = 1;
269         arg_list.pointer = &arg;
270         arg.type = ACPI_TYPE_INTEGER;
271         arg.integer.value = 1;
272         status = acpi_evaluate_object(mem_device->device->handle,
273                                       "_EJ0", &arg_list, NULL);
274         /* Return on _EJ0 failure */
275         if (ACPI_FAILURE(status)) {
276                 ACPI_EXCEPTION((AE_INFO, status, "_EJ0 failed"));
277                 return -ENODEV;
278         }
279
280         /* Evalute _STA to check if the device is disabled */
281         status = acpi_evaluate_integer(mem_device->device->handle, "_STA",
282                                        NULL, &current_status);
283         if (ACPI_FAILURE(status))
284                 return -ENODEV;
285
286         /* Check for device status.  Device should be disabled */
287         if (current_status & ACPI_MEMORY_STA_ENABLED)
288                 return -EINVAL;
289
290         return 0;
291 }
292
293 static int acpi_memory_disable_device(struct acpi_memory_device *mem_device)
294 {
295         int result;
296         struct acpi_memory_info *info, *n;
297
298
299         /*
300          * Ask the VM to offline this memory range.
301          * Note: Assume that this function returns zero on success
302          */
303         list_for_each_entry_safe(info, n, &mem_device->res_list, list) {
304                 if (info->enabled) {
305                         result = remove_memory(info->start_addr, info->length);
306                         if (result)
307                                 return result;
308                 }
309                 kfree(info);
310         }
311
312         /* Power-off and eject the device */
313         result = acpi_memory_powerdown_device(mem_device);
314         if (result) {
315                 /* Set the status of the device to invalid */
316                 mem_device->state = MEMORY_INVALID_STATE;
317                 return result;
318         }
319
320         mem_device->state = MEMORY_POWER_OFF_STATE;
321         return result;
322 }
323
324 static void acpi_memory_device_notify(acpi_handle handle, u32 event, void *data)
325 {
326         struct acpi_memory_device *mem_device;
327         struct acpi_device *device;
328
329
330         switch (event) {
331         case ACPI_NOTIFY_BUS_CHECK:
332                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
333                                   "\nReceived BUS CHECK notification for device\n"));
334                 /* Fall Through */
335         case ACPI_NOTIFY_DEVICE_CHECK:
336                 if (event == ACPI_NOTIFY_DEVICE_CHECK)
337                         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
338                                           "\nReceived DEVICE CHECK notification for device\n"));
339                 if (acpi_memory_get_device(handle, &mem_device)) {
340                         printk(KERN_ERR PREFIX "Cannot find driver data\n");
341                         return;
342                 }
343
344                 if (!acpi_memory_check_device(mem_device)) {
345                         if (acpi_memory_enable_device(mem_device))
346                                 printk(KERN_ERR PREFIX
347                                             "Cannot enable memory device\n");
348                 }
349                 break;
350         case ACPI_NOTIFY_EJECT_REQUEST:
351                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
352                                   "\nReceived EJECT REQUEST notification for device\n"));
353
354                 if (acpi_bus_get_device(handle, &device)) {
355                         printk(KERN_ERR PREFIX "Device doesn't exist\n");
356                         break;
357                 }
358                 mem_device = acpi_driver_data(device);
359                 if (!mem_device) {
360                         printk(KERN_ERR PREFIX "Driver Data is NULL\n");
361                         break;
362                 }
363
364                 /*
365                  * Currently disabling memory device from kernel mode
366                  * TBD: Can also be disabled from user mode scripts
367                  * TBD: Can also be disabled by Callback registration
368                  *      with generic sysfs driver
369                  */
370                 if (acpi_memory_disable_device(mem_device))
371                         printk(KERN_ERR PREFIX
372                                     "Disable memory device\n");
373                 /*
374                  * TBD: Invoke acpi_bus_remove to cleanup data structures
375                  */
376                 break;
377         default:
378                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
379                                   "Unsupported event [0x%x]\n", event));
380                 break;
381         }
382
383         return;
384 }
385
386 static int acpi_memory_device_add(struct acpi_device *device)
387 {
388         int result;
389         struct acpi_memory_device *mem_device = NULL;
390
391
392         if (!device)
393                 return -EINVAL;
394
395         mem_device = kmalloc(sizeof(struct acpi_memory_device), GFP_KERNEL);
396         if (!mem_device)
397                 return -ENOMEM;
398         memset(mem_device, 0, sizeof(struct acpi_memory_device));
399
400         INIT_LIST_HEAD(&mem_device->res_list);
401         mem_device->device = device;
402         sprintf(acpi_device_name(device), "%s", ACPI_MEMORY_DEVICE_NAME);
403         sprintf(acpi_device_class(device), "%s", ACPI_MEMORY_DEVICE_CLASS);
404         acpi_driver_data(device) = mem_device;
405
406         /* Get the range from the _CRS */
407         result = acpi_memory_get_device_resources(mem_device);
408         if (result) {
409                 kfree(mem_device);
410                 return result;
411         }
412
413         /* Set the device state */
414         mem_device->state = MEMORY_POWER_ON_STATE;
415
416         printk(KERN_INFO "%s \n", acpi_device_name(device));
417
418         return result;
419 }
420
421 static int acpi_memory_device_remove(struct acpi_device *device, int type)
422 {
423         struct acpi_memory_device *mem_device = NULL;
424
425
426         if (!device || !acpi_driver_data(device))
427                 return -EINVAL;
428
429         mem_device = (struct acpi_memory_device *)acpi_driver_data(device);
430         kfree(mem_device);
431
432         return 0;
433 }
434
435 static int acpi_memory_device_start (struct acpi_device *device)
436 {
437         struct acpi_memory_device *mem_device;
438         int result = 0;
439
440         mem_device = acpi_driver_data(device);
441
442         if (!acpi_memory_check_device(mem_device)) {
443                 /* call add_memory func */
444                 result = acpi_memory_enable_device(mem_device);
445                 if (result)
446                         ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
447                                 "Error in acpi_memory_enable_device\n"));
448         }
449         return result;
450 }
451
452 /*
453  * Helper function to check for memory device
454  */
455 static acpi_status is_memory_device(acpi_handle handle)
456 {
457         char *hardware_id;
458         acpi_status status;
459         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
460         struct acpi_device_info *info;
461
462
463         status = acpi_get_object_info(handle, &buffer);
464         if (ACPI_FAILURE(status))
465                 return status;
466
467         info = buffer.pointer;
468         if (!(info->valid & ACPI_VALID_HID)) {
469                 kfree(buffer.pointer);
470                 return AE_ERROR;
471         }
472
473         hardware_id = info->hardware_id.value;
474         if ((hardware_id == NULL) ||
475             (strcmp(hardware_id, ACPI_MEMORY_DEVICE_HID)))
476                 status = AE_ERROR;
477
478         kfree(buffer.pointer);
479         return status;
480 }
481
482 static acpi_status
483 acpi_memory_register_notify_handler(acpi_handle handle,
484                                     u32 level, void *ctxt, void **retv)
485 {
486         acpi_status status;
487
488
489         status = is_memory_device(handle);
490         if (ACPI_FAILURE(status)){
491                 ACPI_EXCEPTION((AE_INFO, status, "handle is no memory device"));
492                 return AE_OK;   /* continue */
493         }
494
495         status = acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
496                                              acpi_memory_device_notify, NULL);
497         /* continue */
498         return AE_OK;
499 }
500
501 static acpi_status
502 acpi_memory_deregister_notify_handler(acpi_handle handle,
503                                       u32 level, void *ctxt, void **retv)
504 {
505         acpi_status status;
506
507
508         status = is_memory_device(handle);
509         if (ACPI_FAILURE(status)){
510                 ACPI_EXCEPTION((AE_INFO, status, "handle is no memory device"));
511                 return AE_OK;   /* continue */
512         }
513
514         status = acpi_remove_notify_handler(handle,
515                                             ACPI_SYSTEM_NOTIFY,
516                                             acpi_memory_device_notify);
517
518         return AE_OK;   /* continue */
519 }
520
521 static int __init acpi_memory_device_init(void)
522 {
523         int result;
524         acpi_status status;
525
526
527         result = acpi_bus_register_driver(&acpi_memory_device_driver);
528
529         if (result < 0)
530                 return -ENODEV;
531
532         status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
533                                      ACPI_UINT32_MAX,
534                                      acpi_memory_register_notify_handler,
535                                      NULL, NULL);
536
537         if (ACPI_FAILURE(status)) {
538                 ACPI_EXCEPTION((AE_INFO, status, "walk_namespace failed"));
539                 acpi_bus_unregister_driver(&acpi_memory_device_driver);
540                 return -ENODEV;
541         }
542
543         return 0;
544 }
545
546 static void __exit acpi_memory_device_exit(void)
547 {
548         acpi_status status;
549
550
551         /*
552          * Adding this to un-install notification handlers for all the device
553          * handles.
554          */
555         status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
556                                      ACPI_UINT32_MAX,
557                                      acpi_memory_deregister_notify_handler,
558                                      NULL, NULL);
559
560         if (ACPI_FAILURE(status))
561                 ACPI_EXCEPTION((AE_INFO, status, "walk_namespace failed"));
562
563         acpi_bus_unregister_driver(&acpi_memory_device_driver);
564
565         return;
566 }
567
568 module_init(acpi_memory_device_init);
569 module_exit(acpi_memory_device_exit);