ACPI: pci_root: simplify acpi_pci_root_add() control flow
[linux-2.6.git] / drivers / acpi / pci_root.c
1 /*
2  *  pci_root.c - ACPI PCI Root Bridge Driver ($Revision: 40 $)
3  *
4  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
5  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
6  *
7  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
8  *
9  *  This program is free software; you can redistribute it and/or modify
10  *  it under the terms of the GNU General Public License as published by
11  *  the Free Software Foundation; either version 2 of the License, or (at
12  *  your option) any later version.
13  *
14  *  This program is distributed in the hope that it will be useful, but
15  *  WITHOUT ANY WARRANTY; without even the implied warranty of
16  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17  *  General Public License for more details.
18  *
19  *  You should have received a copy of the GNU General Public License along
20  *  with this program; if not, write to the Free Software Foundation, Inc.,
21  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
22  *
23  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
24  */
25
26 #include <linux/kernel.h>
27 #include <linux/module.h>
28 #include <linux/init.h>
29 #include <linux/types.h>
30 #include <linux/proc_fs.h>
31 #include <linux/spinlock.h>
32 #include <linux/pm.h>
33 #include <linux/pci.h>
34 #include <linux/pci-acpi.h>
35 #include <linux/acpi.h>
36 #include <acpi/acpi_bus.h>
37 #include <acpi/acpi_drivers.h>
38
39 #define _COMPONENT              ACPI_PCI_COMPONENT
40 ACPI_MODULE_NAME("pci_root");
41 #define ACPI_PCI_ROOT_CLASS             "pci_bridge"
42 #define ACPI_PCI_ROOT_DEVICE_NAME       "PCI Root Bridge"
43 static int acpi_pci_root_add(struct acpi_device *device);
44 static int acpi_pci_root_remove(struct acpi_device *device, int type);
45 static int acpi_pci_root_start(struct acpi_device *device);
46
47 static struct acpi_device_id root_device_ids[] = {
48         {"PNP0A03", 0},
49         {"", 0},
50 };
51 MODULE_DEVICE_TABLE(acpi, root_device_ids);
52
53 static struct acpi_driver acpi_pci_root_driver = {
54         .name = "pci_root",
55         .class = ACPI_PCI_ROOT_CLASS,
56         .ids = root_device_ids,
57         .ops = {
58                 .add = acpi_pci_root_add,
59                 .remove = acpi_pci_root_remove,
60                 .start = acpi_pci_root_start,
61                 },
62 };
63
64 struct acpi_pci_root {
65         struct list_head node;
66         struct acpi_device * device;
67         struct acpi_pci_id id;
68         struct pci_bus *bus;
69
70         u32 osc_support_set;    /* _OSC state of support bits */
71         u32 osc_control_set;    /* _OSC state of control bits */
72         u32 osc_control_qry;    /* the latest _OSC query result */
73
74         u32 osc_queried:1;      /* has _OSC control been queried? */
75 };
76
77 static LIST_HEAD(acpi_pci_roots);
78
79 static struct acpi_pci_driver *sub_driver;
80 static DEFINE_MUTEX(osc_lock);
81
82 int acpi_pci_register_driver(struct acpi_pci_driver *driver)
83 {
84         int n = 0;
85         struct list_head *entry;
86
87         struct acpi_pci_driver **pptr = &sub_driver;
88         while (*pptr)
89                 pptr = &(*pptr)->next;
90         *pptr = driver;
91
92         if (!driver->add)
93                 return 0;
94
95         list_for_each(entry, &acpi_pci_roots) {
96                 struct acpi_pci_root *root;
97                 root = list_entry(entry, struct acpi_pci_root, node);
98                 driver->add(root->device->handle);
99                 n++;
100         }
101
102         return n;
103 }
104
105 EXPORT_SYMBOL(acpi_pci_register_driver);
106
107 void acpi_pci_unregister_driver(struct acpi_pci_driver *driver)
108 {
109         struct list_head *entry;
110
111         struct acpi_pci_driver **pptr = &sub_driver;
112         while (*pptr) {
113                 if (*pptr == driver)
114                         break;
115                 pptr = &(*pptr)->next;
116         }
117         BUG_ON(!*pptr);
118         *pptr = (*pptr)->next;
119
120         if (!driver->remove)
121                 return;
122
123         list_for_each(entry, &acpi_pci_roots) {
124                 struct acpi_pci_root *root;
125                 root = list_entry(entry, struct acpi_pci_root, node);
126                 driver->remove(root->device->handle);
127         }
128 }
129
130 EXPORT_SYMBOL(acpi_pci_unregister_driver);
131
132 acpi_handle acpi_get_pci_rootbridge_handle(unsigned int seg, unsigned int bus)
133 {
134         struct acpi_pci_root *tmp;
135         
136         list_for_each_entry(tmp, &acpi_pci_roots, node) {
137                 if ((tmp->id.segment == (u16) seg) && (tmp->id.bus == (u16) bus))
138                         return tmp->device->handle;
139         }
140         return NULL;            
141 }
142
143 EXPORT_SYMBOL_GPL(acpi_get_pci_rootbridge_handle);
144
145 static acpi_status
146 get_root_bridge_busnr_callback(struct acpi_resource *resource, void *data)
147 {
148         int *busnr = data;
149         struct acpi_resource_address64 address;
150
151         if (resource->type != ACPI_RESOURCE_TYPE_ADDRESS16 &&
152             resource->type != ACPI_RESOURCE_TYPE_ADDRESS32 &&
153             resource->type != ACPI_RESOURCE_TYPE_ADDRESS64)
154                 return AE_OK;
155
156         acpi_resource_to_address64(resource, &address);
157         if ((address.address_length > 0) &&
158             (address.resource_type == ACPI_BUS_NUMBER_RANGE))
159                 *busnr = address.minimum;
160
161         return AE_OK;
162 }
163
164 static acpi_status try_get_root_bridge_busnr(acpi_handle handle,
165                                              unsigned long long *bus)
166 {
167         acpi_status status;
168         int busnum;
169
170         busnum = -1;
171         status =
172             acpi_walk_resources(handle, METHOD_NAME__CRS,
173                                 get_root_bridge_busnr_callback, &busnum);
174         if (ACPI_FAILURE(status))
175                 return status;
176         /* Check if we really get a bus number from _CRS */
177         if (busnum == -1)
178                 return AE_ERROR;
179         *bus = busnum;
180         return AE_OK;
181 }
182
183 static void acpi_pci_bridge_scan(struct acpi_device *device)
184 {
185         int status;
186         struct acpi_device *child = NULL;
187
188         if (device->flags.bus_address)
189                 if (device->parent && device->parent->ops.bind) {
190                         status = device->parent->ops.bind(device);
191                         if (!status) {
192                                 list_for_each_entry(child, &device->children, node)
193                                         acpi_pci_bridge_scan(child);
194                         }
195                 }
196 }
197
198 static u8 OSC_UUID[16] = {0x5B, 0x4D, 0xDB, 0x33, 0xF7, 0x1F, 0x1C, 0x40,
199                           0x96, 0x57, 0x74, 0x41, 0xC0, 0x3D, 0xD7, 0x66};
200
201 static acpi_status acpi_pci_run_osc(acpi_handle handle,
202                                     const u32 *capbuf, u32 *retval)
203 {
204         acpi_status status;
205         struct acpi_object_list input;
206         union acpi_object in_params[4];
207         struct acpi_buffer output = {ACPI_ALLOCATE_BUFFER, NULL};
208         union acpi_object *out_obj;
209         u32 errors;
210
211         /* Setting up input parameters */
212         input.count = 4;
213         input.pointer = in_params;
214         in_params[0].type               = ACPI_TYPE_BUFFER;
215         in_params[0].buffer.length      = 16;
216         in_params[0].buffer.pointer     = OSC_UUID;
217         in_params[1].type               = ACPI_TYPE_INTEGER;
218         in_params[1].integer.value      = 1;
219         in_params[2].type               = ACPI_TYPE_INTEGER;
220         in_params[2].integer.value      = 3;
221         in_params[3].type               = ACPI_TYPE_BUFFER;
222         in_params[3].buffer.length      = 12;
223         in_params[3].buffer.pointer     = (u8 *)capbuf;
224
225         status = acpi_evaluate_object(handle, "_OSC", &input, &output);
226         if (ACPI_FAILURE(status))
227                 return status;
228
229         if (!output.length)
230                 return AE_NULL_OBJECT;
231
232         out_obj = output.pointer;
233         if (out_obj->type != ACPI_TYPE_BUFFER) {
234                 printk(KERN_DEBUG "_OSC evaluation returned wrong type\n");
235                 status = AE_TYPE;
236                 goto out_kfree;
237         }
238         /* Need to ignore the bit0 in result code */
239         errors = *((u32 *)out_obj->buffer.pointer) & ~(1 << 0);
240         if (errors) {
241                 if (errors & OSC_REQUEST_ERROR)
242                         printk(KERN_DEBUG "_OSC request failed\n");
243                 if (errors & OSC_INVALID_UUID_ERROR)
244                         printk(KERN_DEBUG "_OSC invalid UUID\n");
245                 if (errors & OSC_INVALID_REVISION_ERROR)
246                         printk(KERN_DEBUG "_OSC invalid revision\n");
247                 if (errors & OSC_CAPABILITIES_MASK_ERROR) {
248                         if (capbuf[OSC_QUERY_TYPE] & OSC_QUERY_ENABLE)
249                                 goto out_success;
250                         printk(KERN_DEBUG
251                                "Firmware did not grant requested _OSC control\n");
252                         status = AE_SUPPORT;
253                         goto out_kfree;
254                 }
255                 status = AE_ERROR;
256                 goto out_kfree;
257         }
258 out_success:
259         *retval = *((u32 *)(out_obj->buffer.pointer + 8));
260         status = AE_OK;
261
262 out_kfree:
263         kfree(output.pointer);
264         return status;
265 }
266
267 static acpi_status acpi_pci_query_osc(struct acpi_pci_root *root, u32 flags)
268 {
269         acpi_status status;
270         u32 support_set, result, capbuf[3];
271
272         /* do _OSC query for all possible controls */
273         support_set = root->osc_support_set | (flags & OSC_SUPPORT_MASKS);
274         capbuf[OSC_QUERY_TYPE] = OSC_QUERY_ENABLE;
275         capbuf[OSC_SUPPORT_TYPE] = support_set;
276         capbuf[OSC_CONTROL_TYPE] = OSC_CONTROL_MASKS;
277
278         status = acpi_pci_run_osc(root->device->handle, capbuf, &result);
279         if (ACPI_SUCCESS(status)) {
280                 root->osc_support_set = support_set;
281                 root->osc_control_qry = result;
282                 root->osc_queried = 1;
283         }
284         return status;
285 }
286
287 static acpi_status acpi_pci_osc_support(struct acpi_pci_root *root, u32 flags)
288 {
289         acpi_status status;
290         acpi_handle tmp;
291
292         status = acpi_get_handle(root->device->handle, "_OSC", &tmp);
293         if (ACPI_FAILURE(status))
294                 return status;
295         mutex_lock(&osc_lock);
296         status = acpi_pci_query_osc(root, flags);
297         mutex_unlock(&osc_lock);
298         return status;
299 }
300
301 static struct acpi_pci_root *acpi_pci_find_root(acpi_handle handle)
302 {
303         struct acpi_pci_root *root;
304         list_for_each_entry(root, &acpi_pci_roots, node) {
305                 if (root->device->handle == handle)
306                         return root;
307         }
308         return NULL;
309 }
310
311 /**
312  * acpi_pci_osc_control_set - commit requested control to Firmware
313  * @handle: acpi_handle for the target ACPI object
314  * @flags: driver's requested control bits
315  *
316  * Attempt to take control from Firmware on requested control bits.
317  **/
318 acpi_status acpi_pci_osc_control_set(acpi_handle handle, u32 flags)
319 {
320         acpi_status status;
321         u32 control_req, result, capbuf[3];
322         acpi_handle tmp;
323         struct acpi_pci_root *root;
324
325         status = acpi_get_handle(handle, "_OSC", &tmp);
326         if (ACPI_FAILURE(status))
327                 return status;
328
329         control_req = (flags & OSC_CONTROL_MASKS);
330         if (!control_req)
331                 return AE_TYPE;
332
333         root = acpi_pci_find_root(handle);
334         if (!root)
335                 return AE_NOT_EXIST;
336
337         mutex_lock(&osc_lock);
338         /* No need to evaluate _OSC if the control was already granted. */
339         if ((root->osc_control_set & control_req) == control_req)
340                 goto out;
341
342         /* Need to query controls first before requesting them */
343         if (!root->osc_queried) {
344                 status = acpi_pci_query_osc(root, root->osc_support_set);
345                 if (ACPI_FAILURE(status))
346                         goto out;
347         }
348         if ((root->osc_control_qry & control_req) != control_req) {
349                 printk(KERN_DEBUG
350                        "Firmware did not grant requested _OSC control\n");
351                 status = AE_SUPPORT;
352                 goto out;
353         }
354
355         capbuf[OSC_QUERY_TYPE] = 0;
356         capbuf[OSC_SUPPORT_TYPE] = root->osc_support_set;
357         capbuf[OSC_CONTROL_TYPE] = root->osc_control_set | control_req;
358         status = acpi_pci_run_osc(handle, capbuf, &result);
359         if (ACPI_SUCCESS(status))
360                 root->osc_control_set = result;
361 out:
362         mutex_unlock(&osc_lock);
363         return status;
364 }
365 EXPORT_SYMBOL(acpi_pci_osc_control_set);
366
367 static int __devinit acpi_pci_root_add(struct acpi_device *device)
368 {
369         unsigned long long segment, bus;
370         acpi_status status;
371         int result;
372         struct acpi_pci_root *root;
373         acpi_handle handle;
374         struct acpi_device *child;
375         u32 flags, base_flags;
376
377         segment = 0;
378         status = acpi_evaluate_integer(device->handle, METHOD_NAME__SEG, NULL,
379                                        &segment);
380         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
381                 printk(KERN_ERR PREFIX "can't evaluate _SEG\n");
382                 return -ENODEV;
383         }
384
385         /* Check _CRS first, then _BBN.  If no _BBN, default to zero. */
386         bus = 0;
387         status = try_get_root_bridge_busnr(device->handle, &bus);
388         if (ACPI_FAILURE(status)) {
389                 status = acpi_evaluate_integer(device->handle, METHOD_NAME__BBN,                                               NULL, &bus);
390                 if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
391                         printk(KERN_ERR PREFIX
392                              "no bus number in _CRS and can't evaluate _BBN\n");
393                         return -ENODEV;
394                 }
395         }
396
397         root = kzalloc(sizeof(struct acpi_pci_root), GFP_KERNEL);
398         if (!root)
399                 return -ENOMEM;
400
401         INIT_LIST_HEAD(&root->node);
402         root->device = device;
403         strcpy(acpi_device_name(device), ACPI_PCI_ROOT_DEVICE_NAME);
404         strcpy(acpi_device_class(device), ACPI_PCI_ROOT_CLASS);
405         device->driver_data = root;
406
407         device->ops.bind = acpi_pci_bind;
408
409         /*
410          * All supported architectures that use ACPI have support for
411          * PCI domains, so we indicate this in _OSC support capabilities.
412          */
413         flags = base_flags = OSC_PCI_SEGMENT_GROUPS_SUPPORT;
414         acpi_pci_osc_support(root, flags);
415
416         /*
417          * Device & Function
418          * -----------------
419          * Obtained from _ADR (which has already been evaluated for us).
420          */
421         root->id.segment = segment & 0xFFFF;
422         root->id.bus = bus & 0xFF;
423         root->id.device = device->pnp.bus_address >> 16;
424         root->id.function = device->pnp.bus_address & 0xFFFF;
425
426         /*
427          * TBD: Need PCI interface for enumeration/configuration of roots.
428          */
429
430         /* TBD: Locking */
431         list_add_tail(&root->node, &acpi_pci_roots);
432
433         printk(KERN_INFO PREFIX "%s [%s] (%04x:%02x)\n",
434                acpi_device_name(device), acpi_device_bid(device),
435                root->id.segment, root->id.bus);
436
437         /*
438          * Scan the Root Bridge
439          * --------------------
440          * Must do this prior to any attempt to bind the root device, as the
441          * PCI namespace does not get created until this call is made (and 
442          * thus the root bridge's pci_dev does not exist).
443          */
444         root->bus = pci_acpi_scan_root(device, root->id.segment, root->id.bus);
445         if (!root->bus) {
446                 printk(KERN_ERR PREFIX
447                             "Bus %04x:%02x not present in PCI namespace\n",
448                             root->id.segment, root->id.bus);
449                 result = -ENODEV;
450                 goto end;
451         }
452
453         /*
454          * Attach ACPI-PCI Context
455          * -----------------------
456          * Thus binding the ACPI and PCI devices.
457          */
458         result = acpi_pci_bind_root(device, &root->id, root->bus);
459         if (result)
460                 goto end;
461
462         /*
463          * PCI Routing Table
464          * -----------------
465          * Evaluate and parse _PRT, if exists.
466          */
467         status = acpi_get_handle(device->handle, METHOD_NAME__PRT, &handle);
468         if (ACPI_SUCCESS(status))
469                 result = acpi_pci_irq_add_prt(device->handle, root->id.segment,
470                                               root->id.bus);
471
472         /*
473          * Scan and bind all _ADR-Based Devices
474          */
475         list_for_each_entry(child, &device->children, node)
476                 acpi_pci_bridge_scan(child);
477
478         /* Indicate support for various _OSC capabilities. */
479         if (pci_ext_cfg_avail(root->bus->self))
480                 flags |= OSC_EXT_PCI_CONFIG_SUPPORT;
481         if (pcie_aspm_enabled())
482                 flags |= OSC_ACTIVE_STATE_PWR_SUPPORT |
483                         OSC_CLOCK_PWR_CAPABILITY_SUPPORT;
484         if (pci_msi_enabled())
485                 flags |= OSC_MSI_SUPPORT;
486         if (flags != base_flags)
487                 acpi_pci_osc_support(root, flags);
488
489         return 0;
490
491 end:
492         if (!list_empty(&root->node))
493                 list_del(&root->node);
494         kfree(root);
495         return result;
496 }
497
498 static int acpi_pci_root_start(struct acpi_device *device)
499 {
500         struct acpi_pci_root *root;
501
502
503         list_for_each_entry(root, &acpi_pci_roots, node) {
504                 if (root->device == device) {
505                         pci_bus_add_devices(root->bus);
506                         return 0;
507                 }
508         }
509         return -ENODEV;
510 }
511
512 static int acpi_pci_root_remove(struct acpi_device *device, int type)
513 {
514         struct acpi_pci_root *root = NULL;
515
516
517         if (!device || !acpi_driver_data(device))
518                 return -EINVAL;
519
520         root = acpi_driver_data(device);
521
522         kfree(root);
523
524         return 0;
525 }
526
527 static int __init acpi_pci_root_init(void)
528 {
529         if (acpi_pci_disabled)
530                 return 0;
531
532         if (acpi_bus_register_driver(&acpi_pci_root_driver) < 0)
533                 return -ENODEV;
534
535         return 0;
536 }
537
538 subsys_initcall(acpi_pci_root_init);