ACPI: pci_root: simplify list traversals
[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 acpi_pci_root *root;
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(root, &acpi_pci_roots, node) {
96                 driver->add(root->device->handle);
97                 n++;
98         }
99
100         return n;
101 }
102
103 EXPORT_SYMBOL(acpi_pci_register_driver);
104
105 void acpi_pci_unregister_driver(struct acpi_pci_driver *driver)
106 {
107         struct acpi_pci_root *root;
108
109         struct acpi_pci_driver **pptr = &sub_driver;
110         while (*pptr) {
111                 if (*pptr == driver)
112                         break;
113                 pptr = &(*pptr)->next;
114         }
115         BUG_ON(!*pptr);
116         *pptr = (*pptr)->next;
117
118         if (!driver->remove)
119                 return;
120
121         list_for_each_entry(root, &acpi_pci_roots, node)
122                 driver->remove(root->device->handle);
123 }
124
125 EXPORT_SYMBOL(acpi_pci_unregister_driver);
126
127 acpi_handle acpi_get_pci_rootbridge_handle(unsigned int seg, unsigned int bus)
128 {
129         struct acpi_pci_root *root;
130         
131         list_for_each_entry(root, &acpi_pci_roots, node)
132                 if ((root->id.segment == (u16) seg) && (root->id.bus == (u16) bus))
133                         return root->device->handle;
134         return NULL;            
135 }
136
137 EXPORT_SYMBOL_GPL(acpi_get_pci_rootbridge_handle);
138
139 static acpi_status
140 get_root_bridge_busnr_callback(struct acpi_resource *resource, void *data)
141 {
142         int *busnr = data;
143         struct acpi_resource_address64 address;
144
145         if (resource->type != ACPI_RESOURCE_TYPE_ADDRESS16 &&
146             resource->type != ACPI_RESOURCE_TYPE_ADDRESS32 &&
147             resource->type != ACPI_RESOURCE_TYPE_ADDRESS64)
148                 return AE_OK;
149
150         acpi_resource_to_address64(resource, &address);
151         if ((address.address_length > 0) &&
152             (address.resource_type == ACPI_BUS_NUMBER_RANGE))
153                 *busnr = address.minimum;
154
155         return AE_OK;
156 }
157
158 static acpi_status try_get_root_bridge_busnr(acpi_handle handle,
159                                              unsigned long long *bus)
160 {
161         acpi_status status;
162         int busnum;
163
164         busnum = -1;
165         status =
166             acpi_walk_resources(handle, METHOD_NAME__CRS,
167                                 get_root_bridge_busnr_callback, &busnum);
168         if (ACPI_FAILURE(status))
169                 return status;
170         /* Check if we really get a bus number from _CRS */
171         if (busnum == -1)
172                 return AE_ERROR;
173         *bus = busnum;
174         return AE_OK;
175 }
176
177 static void acpi_pci_bridge_scan(struct acpi_device *device)
178 {
179         int status;
180         struct acpi_device *child = NULL;
181
182         if (device->flags.bus_address)
183                 if (device->parent && device->parent->ops.bind) {
184                         status = device->parent->ops.bind(device);
185                         if (!status) {
186                                 list_for_each_entry(child, &device->children, node)
187                                         acpi_pci_bridge_scan(child);
188                         }
189                 }
190 }
191
192 static u8 OSC_UUID[16] = {0x5B, 0x4D, 0xDB, 0x33, 0xF7, 0x1F, 0x1C, 0x40,
193                           0x96, 0x57, 0x74, 0x41, 0xC0, 0x3D, 0xD7, 0x66};
194
195 static acpi_status acpi_pci_run_osc(acpi_handle handle,
196                                     const u32 *capbuf, u32 *retval)
197 {
198         acpi_status status;
199         struct acpi_object_list input;
200         union acpi_object in_params[4];
201         struct acpi_buffer output = {ACPI_ALLOCATE_BUFFER, NULL};
202         union acpi_object *out_obj;
203         u32 errors;
204
205         /* Setting up input parameters */
206         input.count = 4;
207         input.pointer = in_params;
208         in_params[0].type               = ACPI_TYPE_BUFFER;
209         in_params[0].buffer.length      = 16;
210         in_params[0].buffer.pointer     = OSC_UUID;
211         in_params[1].type               = ACPI_TYPE_INTEGER;
212         in_params[1].integer.value      = 1;
213         in_params[2].type               = ACPI_TYPE_INTEGER;
214         in_params[2].integer.value      = 3;
215         in_params[3].type               = ACPI_TYPE_BUFFER;
216         in_params[3].buffer.length      = 12;
217         in_params[3].buffer.pointer     = (u8 *)capbuf;
218
219         status = acpi_evaluate_object(handle, "_OSC", &input, &output);
220         if (ACPI_FAILURE(status))
221                 return status;
222
223         if (!output.length)
224                 return AE_NULL_OBJECT;
225
226         out_obj = output.pointer;
227         if (out_obj->type != ACPI_TYPE_BUFFER) {
228                 printk(KERN_DEBUG "_OSC evaluation returned wrong type\n");
229                 status = AE_TYPE;
230                 goto out_kfree;
231         }
232         /* Need to ignore the bit0 in result code */
233         errors = *((u32 *)out_obj->buffer.pointer) & ~(1 << 0);
234         if (errors) {
235                 if (errors & OSC_REQUEST_ERROR)
236                         printk(KERN_DEBUG "_OSC request failed\n");
237                 if (errors & OSC_INVALID_UUID_ERROR)
238                         printk(KERN_DEBUG "_OSC invalid UUID\n");
239                 if (errors & OSC_INVALID_REVISION_ERROR)
240                         printk(KERN_DEBUG "_OSC invalid revision\n");
241                 if (errors & OSC_CAPABILITIES_MASK_ERROR) {
242                         if (capbuf[OSC_QUERY_TYPE] & OSC_QUERY_ENABLE)
243                                 goto out_success;
244                         printk(KERN_DEBUG
245                                "Firmware did not grant requested _OSC control\n");
246                         status = AE_SUPPORT;
247                         goto out_kfree;
248                 }
249                 status = AE_ERROR;
250                 goto out_kfree;
251         }
252 out_success:
253         *retval = *((u32 *)(out_obj->buffer.pointer + 8));
254         status = AE_OK;
255
256 out_kfree:
257         kfree(output.pointer);
258         return status;
259 }
260
261 static acpi_status acpi_pci_query_osc(struct acpi_pci_root *root, u32 flags)
262 {
263         acpi_status status;
264         u32 support_set, result, capbuf[3];
265
266         /* do _OSC query for all possible controls */
267         support_set = root->osc_support_set | (flags & OSC_SUPPORT_MASKS);
268         capbuf[OSC_QUERY_TYPE] = OSC_QUERY_ENABLE;
269         capbuf[OSC_SUPPORT_TYPE] = support_set;
270         capbuf[OSC_CONTROL_TYPE] = OSC_CONTROL_MASKS;
271
272         status = acpi_pci_run_osc(root->device->handle, capbuf, &result);
273         if (ACPI_SUCCESS(status)) {
274                 root->osc_support_set = support_set;
275                 root->osc_control_qry = result;
276                 root->osc_queried = 1;
277         }
278         return status;
279 }
280
281 static acpi_status acpi_pci_osc_support(struct acpi_pci_root *root, u32 flags)
282 {
283         acpi_status status;
284         acpi_handle tmp;
285
286         status = acpi_get_handle(root->device->handle, "_OSC", &tmp);
287         if (ACPI_FAILURE(status))
288                 return status;
289         mutex_lock(&osc_lock);
290         status = acpi_pci_query_osc(root, flags);
291         mutex_unlock(&osc_lock);
292         return status;
293 }
294
295 static struct acpi_pci_root *acpi_pci_find_root(acpi_handle handle)
296 {
297         struct acpi_pci_root *root;
298
299         list_for_each_entry(root, &acpi_pci_roots, node) {
300                 if (root->device->handle == handle)
301                         return root;
302         }
303         return NULL;
304 }
305
306 /**
307  * acpi_pci_osc_control_set - commit requested control to Firmware
308  * @handle: acpi_handle for the target ACPI object
309  * @flags: driver's requested control bits
310  *
311  * Attempt to take control from Firmware on requested control bits.
312  **/
313 acpi_status acpi_pci_osc_control_set(acpi_handle handle, u32 flags)
314 {
315         acpi_status status;
316         u32 control_req, result, capbuf[3];
317         acpi_handle tmp;
318         struct acpi_pci_root *root;
319
320         status = acpi_get_handle(handle, "_OSC", &tmp);
321         if (ACPI_FAILURE(status))
322                 return status;
323
324         control_req = (flags & OSC_CONTROL_MASKS);
325         if (!control_req)
326                 return AE_TYPE;
327
328         root = acpi_pci_find_root(handle);
329         if (!root)
330                 return AE_NOT_EXIST;
331
332         mutex_lock(&osc_lock);
333         /* No need to evaluate _OSC if the control was already granted. */
334         if ((root->osc_control_set & control_req) == control_req)
335                 goto out;
336
337         /* Need to query controls first before requesting them */
338         if (!root->osc_queried) {
339                 status = acpi_pci_query_osc(root, root->osc_support_set);
340                 if (ACPI_FAILURE(status))
341                         goto out;
342         }
343         if ((root->osc_control_qry & control_req) != control_req) {
344                 printk(KERN_DEBUG
345                        "Firmware did not grant requested _OSC control\n");
346                 status = AE_SUPPORT;
347                 goto out;
348         }
349
350         capbuf[OSC_QUERY_TYPE] = 0;
351         capbuf[OSC_SUPPORT_TYPE] = root->osc_support_set;
352         capbuf[OSC_CONTROL_TYPE] = root->osc_control_set | control_req;
353         status = acpi_pci_run_osc(handle, capbuf, &result);
354         if (ACPI_SUCCESS(status))
355                 root->osc_control_set = result;
356 out:
357         mutex_unlock(&osc_lock);
358         return status;
359 }
360 EXPORT_SYMBOL(acpi_pci_osc_control_set);
361
362 static int __devinit acpi_pci_root_add(struct acpi_device *device)
363 {
364         unsigned long long segment, bus;
365         acpi_status status;
366         int result;
367         struct acpi_pci_root *root;
368         acpi_handle handle;
369         struct acpi_device *child;
370         u32 flags, base_flags;
371
372         segment = 0;
373         status = acpi_evaluate_integer(device->handle, METHOD_NAME__SEG, NULL,
374                                        &segment);
375         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
376                 printk(KERN_ERR PREFIX "can't evaluate _SEG\n");
377                 return -ENODEV;
378         }
379
380         /* Check _CRS first, then _BBN.  If no _BBN, default to zero. */
381         bus = 0;
382         status = try_get_root_bridge_busnr(device->handle, &bus);
383         if (ACPI_FAILURE(status)) {
384                 status = acpi_evaluate_integer(device->handle, METHOD_NAME__BBN,                                               NULL, &bus);
385                 if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
386                         printk(KERN_ERR PREFIX
387                              "no bus number in _CRS and can't evaluate _BBN\n");
388                         return -ENODEV;
389                 }
390         }
391
392         root = kzalloc(sizeof(struct acpi_pci_root), GFP_KERNEL);
393         if (!root)
394                 return -ENOMEM;
395
396         INIT_LIST_HEAD(&root->node);
397         root->device = device;
398         strcpy(acpi_device_name(device), ACPI_PCI_ROOT_DEVICE_NAME);
399         strcpy(acpi_device_class(device), ACPI_PCI_ROOT_CLASS);
400         device->driver_data = root;
401
402         device->ops.bind = acpi_pci_bind;
403
404         /*
405          * All supported architectures that use ACPI have support for
406          * PCI domains, so we indicate this in _OSC support capabilities.
407          */
408         flags = base_flags = OSC_PCI_SEGMENT_GROUPS_SUPPORT;
409         acpi_pci_osc_support(root, flags);
410
411         /*
412          * Device & Function
413          * -----------------
414          * Obtained from _ADR (which has already been evaluated for us).
415          */
416         root->id.segment = segment & 0xFFFF;
417         root->id.bus = bus & 0xFF;
418         root->id.device = device->pnp.bus_address >> 16;
419         root->id.function = device->pnp.bus_address & 0xFFFF;
420
421         /*
422          * TBD: Need PCI interface for enumeration/configuration of roots.
423          */
424
425         /* TBD: Locking */
426         list_add_tail(&root->node, &acpi_pci_roots);
427
428         printk(KERN_INFO PREFIX "%s [%s] (%04x:%02x)\n",
429                acpi_device_name(device), acpi_device_bid(device),
430                root->id.segment, root->id.bus);
431
432         /*
433          * Scan the Root Bridge
434          * --------------------
435          * Must do this prior to any attempt to bind the root device, as the
436          * PCI namespace does not get created until this call is made (and 
437          * thus the root bridge's pci_dev does not exist).
438          */
439         root->bus = pci_acpi_scan_root(device, root->id.segment, root->id.bus);
440         if (!root->bus) {
441                 printk(KERN_ERR PREFIX
442                             "Bus %04x:%02x not present in PCI namespace\n",
443                             root->id.segment, root->id.bus);
444                 result = -ENODEV;
445                 goto end;
446         }
447
448         /*
449          * Attach ACPI-PCI Context
450          * -----------------------
451          * Thus binding the ACPI and PCI devices.
452          */
453         result = acpi_pci_bind_root(device, &root->id, root->bus);
454         if (result)
455                 goto end;
456
457         /*
458          * PCI Routing Table
459          * -----------------
460          * Evaluate and parse _PRT, if exists.
461          */
462         status = acpi_get_handle(device->handle, METHOD_NAME__PRT, &handle);
463         if (ACPI_SUCCESS(status))
464                 result = acpi_pci_irq_add_prt(device->handle, root->id.segment,
465                                               root->id.bus);
466
467         /*
468          * Scan and bind all _ADR-Based Devices
469          */
470         list_for_each_entry(child, &device->children, node)
471                 acpi_pci_bridge_scan(child);
472
473         /* Indicate support for various _OSC capabilities. */
474         if (pci_ext_cfg_avail(root->bus->self))
475                 flags |= OSC_EXT_PCI_CONFIG_SUPPORT;
476         if (pcie_aspm_enabled())
477                 flags |= OSC_ACTIVE_STATE_PWR_SUPPORT |
478                         OSC_CLOCK_PWR_CAPABILITY_SUPPORT;
479         if (pci_msi_enabled())
480                 flags |= OSC_MSI_SUPPORT;
481         if (flags != base_flags)
482                 acpi_pci_osc_support(root, flags);
483
484         return 0;
485
486 end:
487         if (!list_empty(&root->node))
488                 list_del(&root->node);
489         kfree(root);
490         return result;
491 }
492
493 static int acpi_pci_root_start(struct acpi_device *device)
494 {
495         struct acpi_pci_root *root = acpi_driver_data(device);
496
497         pci_bus_add_devices(root->bus);
498         return 0;
499 }
500
501 static int acpi_pci_root_remove(struct acpi_device *device, int type)
502 {
503         struct acpi_pci_root *root = acpi_driver_data(device);
504
505         kfree(root);
506         return 0;
507 }
508
509 static int __init acpi_pci_root_init(void)
510 {
511         if (acpi_pci_disabled)
512                 return 0;
513
514         if (acpi_bus_register_driver(&acpi_pci_root_driver) < 0)
515                 return -ENODEV;
516
517         return 0;
518 }
519
520 subsys_initcall(acpi_pci_root_init);