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/spinlock.h>
31 #include <linux/pm.h>
32 #include <linux/pm_runtime.h>
33 #include <linux/pci.h>
34 #include <linux/pci-acpi.h>
35 #include <linux/pci-aspm.h>
36 #include <linux/acpi.h>
37 #include <linux/slab.h>
38 #include <acpi/acpi_bus.h>
39 #include <acpi/acpi_drivers.h>
40 #include <acpi/apei.h>
41
42 #define PREFIX "ACPI: "
43
44 #define _COMPONENT ACPI_PCI_COMPONENT
45 ACPI_MODULE_NAME("pci_root");
46 #define ACPI_PCI_ROOT_CLASS "pci_bridge"
47 #define ACPI_PCI_ROOT_DEVICE_NAME "PCI Root Bridge"
48 static int acpi_pci_root_add(struct acpi_device *device);
49 static int acpi_pci_root_remove(struct acpi_device *device, int type);
50 static int acpi_pci_root_start(struct acpi_device *device);
51
52 #define ACPI_PCIE_REQ_SUPPORT (OSC_EXT_PCI_CONFIG_SUPPORT \
53 | OSC_ACTIVE_STATE_PWR_SUPPORT \
54 | OSC_CLOCK_PWR_CAPABILITY_SUPPORT \
55 | OSC_MSI_SUPPORT)
56
57 static const struct acpi_device_id root_device_ids[] = {
58 {"PNP0A03", 0},
59 {"", 0},
60 };
61 MODULE_DEVICE_TABLE(acpi, root_device_ids);
62
63 static struct acpi_driver acpi_pci_root_driver = {
64 .name = "pci_root",
65 .class = ACPI_PCI_ROOT_CLASS,
66 .ids = root_device_ids,
67 .ops = {
68 .add = acpi_pci_root_add,
69 .remove = acpi_pci_root_remove,
70 .start = acpi_pci_root_start,
71 },
72 };
73
74 static LIST_HEAD(acpi_pci_roots);
75
76 static struct acpi_pci_driver *sub_driver;
77 static DEFINE_MUTEX(osc_lock);
78
acpi_pci_register_driver(struct acpi_pci_driver * driver)79 int acpi_pci_register_driver(struct acpi_pci_driver *driver)
80 {
81 int n = 0;
82 struct acpi_pci_root *root;
83
84 struct acpi_pci_driver **pptr = &sub_driver;
85 while (*pptr)
86 pptr = &(*pptr)->next;
87 *pptr = driver;
88
89 if (!driver->add)
90 return 0;
91
92 list_for_each_entry(root, &acpi_pci_roots, node) {
93 driver->add(root->device->handle);
94 n++;
95 }
96
97 return n;
98 }
99
100 EXPORT_SYMBOL(acpi_pci_register_driver);
101
acpi_pci_unregister_driver(struct acpi_pci_driver * driver)102 void acpi_pci_unregister_driver(struct acpi_pci_driver *driver)
103 {
104 struct acpi_pci_root *root;
105
106 struct acpi_pci_driver **pptr = &sub_driver;
107 while (*pptr) {
108 if (*pptr == driver)
109 break;
110 pptr = &(*pptr)->next;
111 }
112 BUG_ON(!*pptr);
113 *pptr = (*pptr)->next;
114
115 if (!driver->remove)
116 return;
117
118 list_for_each_entry(root, &acpi_pci_roots, node)
119 driver->remove(root->device->handle);
120 }
121
122 EXPORT_SYMBOL(acpi_pci_unregister_driver);
123
acpi_get_pci_rootbridge_handle(unsigned int seg,unsigned int bus)124 acpi_handle acpi_get_pci_rootbridge_handle(unsigned int seg, unsigned int bus)
125 {
126 struct acpi_pci_root *root;
127
128 list_for_each_entry(root, &acpi_pci_roots, node)
129 if ((root->segment == (u16) seg) &&
130 (root->secondary.start == (u16) bus))
131 return root->device->handle;
132 return NULL;
133 }
134
135 EXPORT_SYMBOL_GPL(acpi_get_pci_rootbridge_handle);
136
137 /**
138 * acpi_is_root_bridge - determine whether an ACPI CA node is a PCI root bridge
139 * @handle - the ACPI CA node in question.
140 *
141 * Note: we could make this API take a struct acpi_device * instead, but
142 * for now, it's more convenient to operate on an acpi_handle.
143 */
acpi_is_root_bridge(acpi_handle handle)144 int acpi_is_root_bridge(acpi_handle handle)
145 {
146 int ret;
147 struct acpi_device *device;
148
149 ret = acpi_bus_get_device(handle, &device);
150 if (ret)
151 return 0;
152
153 ret = acpi_match_device_ids(device, root_device_ids);
154 if (ret)
155 return 0;
156 else
157 return 1;
158 }
159 EXPORT_SYMBOL_GPL(acpi_is_root_bridge);
160
161 static acpi_status
get_root_bridge_busnr_callback(struct acpi_resource * resource,void * data)162 get_root_bridge_busnr_callback(struct acpi_resource *resource, void *data)
163 {
164 struct resource *res = data;
165 struct acpi_resource_address64 address;
166
167 if (resource->type != ACPI_RESOURCE_TYPE_ADDRESS16 &&
168 resource->type != ACPI_RESOURCE_TYPE_ADDRESS32 &&
169 resource->type != ACPI_RESOURCE_TYPE_ADDRESS64)
170 return AE_OK;
171
172 acpi_resource_to_address64(resource, &address);
173 if ((address.address_length > 0) &&
174 (address.resource_type == ACPI_BUS_NUMBER_RANGE)) {
175 res->start = address.minimum;
176 res->end = address.minimum + address.address_length - 1;
177 }
178
179 return AE_OK;
180 }
181
try_get_root_bridge_busnr(acpi_handle handle,struct resource * res)182 static acpi_status try_get_root_bridge_busnr(acpi_handle handle,
183 struct resource *res)
184 {
185 acpi_status status;
186
187 res->start = -1;
188 status =
189 acpi_walk_resources(handle, METHOD_NAME__CRS,
190 get_root_bridge_busnr_callback, res);
191 if (ACPI_FAILURE(status))
192 return status;
193 if (res->start == -1)
194 return AE_ERROR;
195 return AE_OK;
196 }
197
acpi_pci_bridge_scan(struct acpi_device * device)198 static void acpi_pci_bridge_scan(struct acpi_device *device)
199 {
200 int status;
201 struct acpi_device *child = NULL;
202
203 if (device->flags.bus_address)
204 if (device->parent && device->parent->ops.bind) {
205 status = device->parent->ops.bind(device);
206 if (!status) {
207 list_for_each_entry(child, &device->children, node)
208 acpi_pci_bridge_scan(child);
209 }
210 }
211 }
212
213 static u8 pci_osc_uuid_str[] = "33DB4D5B-1FF7-401C-9657-7441C03DD766";
214
acpi_pci_run_osc(acpi_handle handle,const u32 * capbuf,u32 * retval)215 static acpi_status acpi_pci_run_osc(acpi_handle handle,
216 const u32 *capbuf, u32 *retval)
217 {
218 struct acpi_osc_context context = {
219 .uuid_str = pci_osc_uuid_str,
220 .rev = 1,
221 .cap.length = 12,
222 .cap.pointer = (void *)capbuf,
223 };
224 acpi_status status;
225
226 status = acpi_run_osc(handle, &context);
227 if (ACPI_SUCCESS(status)) {
228 *retval = *((u32 *)(context.ret.pointer + 8));
229 kfree(context.ret.pointer);
230 }
231 return status;
232 }
233
acpi_pci_query_osc(struct acpi_pci_root * root,u32 support,u32 * control)234 static acpi_status acpi_pci_query_osc(struct acpi_pci_root *root,
235 u32 support,
236 u32 *control)
237 {
238 acpi_status status;
239 u32 result, capbuf[3];
240
241 support &= OSC_PCI_SUPPORT_MASKS;
242 support |= root->osc_support_set;
243
244 capbuf[OSC_QUERY_TYPE] = OSC_QUERY_ENABLE;
245 capbuf[OSC_SUPPORT_TYPE] = support;
246 if (control) {
247 *control &= OSC_PCI_CONTROL_MASKS;
248 capbuf[OSC_CONTROL_TYPE] = *control | root->osc_control_set;
249 } else {
250 /* Run _OSC query for all possible controls. */
251 capbuf[OSC_CONTROL_TYPE] = OSC_PCI_CONTROL_MASKS;
252 }
253
254 status = acpi_pci_run_osc(root->device->handle, capbuf, &result);
255 if (ACPI_SUCCESS(status)) {
256 root->osc_support_set = support;
257 if (control)
258 *control = result;
259 }
260 return status;
261 }
262
acpi_pci_osc_support(struct acpi_pci_root * root,u32 flags)263 static acpi_status acpi_pci_osc_support(struct acpi_pci_root *root, u32 flags)
264 {
265 acpi_status status;
266 acpi_handle tmp;
267
268 status = acpi_get_handle(root->device->handle, "_OSC", &tmp);
269 if (ACPI_FAILURE(status))
270 return status;
271 mutex_lock(&osc_lock);
272 status = acpi_pci_query_osc(root, flags, NULL);
273 mutex_unlock(&osc_lock);
274 return status;
275 }
276
acpi_pci_find_root(acpi_handle handle)277 struct acpi_pci_root *acpi_pci_find_root(acpi_handle handle)
278 {
279 struct acpi_pci_root *root;
280
281 list_for_each_entry(root, &acpi_pci_roots, node) {
282 if (root->device->handle == handle)
283 return root;
284 }
285 return NULL;
286 }
287 EXPORT_SYMBOL_GPL(acpi_pci_find_root);
288
289 struct acpi_handle_node {
290 struct list_head node;
291 acpi_handle handle;
292 };
293
294 /**
295 * acpi_get_pci_dev - convert ACPI CA handle to struct pci_dev
296 * @handle: the handle in question
297 *
298 * Given an ACPI CA handle, the desired PCI device is located in the
299 * list of PCI devices.
300 *
301 * If the device is found, its reference count is increased and this
302 * function returns a pointer to its data structure. The caller must
303 * decrement the reference count by calling pci_dev_put().
304 * If no device is found, %NULL is returned.
305 */
acpi_get_pci_dev(acpi_handle handle)306 struct pci_dev *acpi_get_pci_dev(acpi_handle handle)
307 {
308 int dev, fn;
309 unsigned long long adr;
310 acpi_status status;
311 acpi_handle phandle;
312 struct pci_bus *pbus;
313 struct pci_dev *pdev = NULL;
314 struct acpi_handle_node *node, *tmp;
315 struct acpi_pci_root *root;
316 LIST_HEAD(device_list);
317
318 /*
319 * Walk up the ACPI CA namespace until we reach a PCI root bridge.
320 */
321 phandle = handle;
322 while (!acpi_is_root_bridge(phandle)) {
323 node = kzalloc(sizeof(struct acpi_handle_node), GFP_KERNEL);
324 if (!node)
325 goto out;
326
327 INIT_LIST_HEAD(&node->node);
328 node->handle = phandle;
329 list_add(&node->node, &device_list);
330
331 status = acpi_get_parent(phandle, &phandle);
332 if (ACPI_FAILURE(status))
333 goto out;
334 }
335
336 root = acpi_pci_find_root(phandle);
337 if (!root)
338 goto out;
339
340 pbus = root->bus;
341
342 /*
343 * Now, walk back down the PCI device tree until we return to our
344 * original handle. Assumes that everything between the PCI root
345 * bridge and the device we're looking for must be a P2P bridge.
346 */
347 list_for_each_entry(node, &device_list, node) {
348 acpi_handle hnd = node->handle;
349 status = acpi_evaluate_integer(hnd, "_ADR", NULL, &adr);
350 if (ACPI_FAILURE(status))
351 goto out;
352 dev = (adr >> 16) & 0xffff;
353 fn = adr & 0xffff;
354
355 pdev = pci_get_slot(pbus, PCI_DEVFN(dev, fn));
356 if (!pdev || hnd == handle)
357 break;
358
359 pbus = pdev->subordinate;
360 pci_dev_put(pdev);
361
362 /*
363 * This function may be called for a non-PCI device that has a
364 * PCI parent (eg. a disk under a PCI SATA controller). In that
365 * case pdev->subordinate will be NULL for the parent.
366 */
367 if (!pbus) {
368 dev_dbg(&pdev->dev, "Not a PCI-to-PCI bridge\n");
369 pdev = NULL;
370 break;
371 }
372 }
373 out:
374 list_for_each_entry_safe(node, tmp, &device_list, node)
375 kfree(node);
376
377 return pdev;
378 }
379 EXPORT_SYMBOL_GPL(acpi_get_pci_dev);
380
381 /**
382 * acpi_pci_osc_control_set - Request control of PCI root _OSC features.
383 * @handle: ACPI handle of a PCI root bridge (or PCIe Root Complex).
384 * @mask: Mask of _OSC bits to request control of, place to store control mask.
385 * @req: Mask of _OSC bits the control of is essential to the caller.
386 *
387 * Run _OSC query for @mask and if that is successful, compare the returned
388 * mask of control bits with @req. If all of the @req bits are set in the
389 * returned mask, run _OSC request for it.
390 *
391 * The variable at the @mask address may be modified regardless of whether or
392 * not the function returns success. On success it will contain the mask of
393 * _OSC bits the BIOS has granted control of, but its contents are meaningless
394 * on failure.
395 **/
acpi_pci_osc_control_set(acpi_handle handle,u32 * mask,u32 req)396 acpi_status acpi_pci_osc_control_set(acpi_handle handle, u32 *mask, u32 req)
397 {
398 struct acpi_pci_root *root;
399 acpi_status status;
400 u32 ctrl, capbuf[3];
401 acpi_handle tmp;
402
403 if (!mask)
404 return AE_BAD_PARAMETER;
405
406 ctrl = *mask & OSC_PCI_CONTROL_MASKS;
407 if ((ctrl & req) != req)
408 return AE_TYPE;
409
410 root = acpi_pci_find_root(handle);
411 if (!root)
412 return AE_NOT_EXIST;
413
414 status = acpi_get_handle(handle, "_OSC", &tmp);
415 if (ACPI_FAILURE(status))
416 return status;
417
418 mutex_lock(&osc_lock);
419
420 *mask = ctrl | root->osc_control_set;
421 /* No need to evaluate _OSC if the control was already granted. */
422 if ((root->osc_control_set & ctrl) == ctrl)
423 goto out;
424
425 /* Need to check the available controls bits before requesting them. */
426 while (*mask) {
427 status = acpi_pci_query_osc(root, root->osc_support_set, mask);
428 if (ACPI_FAILURE(status))
429 goto out;
430 if (ctrl == *mask)
431 break;
432 ctrl = *mask;
433 }
434
435 if ((ctrl & req) != req) {
436 status = AE_SUPPORT;
437 goto out;
438 }
439
440 capbuf[OSC_QUERY_TYPE] = 0;
441 capbuf[OSC_SUPPORT_TYPE] = root->osc_support_set;
442 capbuf[OSC_CONTROL_TYPE] = ctrl;
443 status = acpi_pci_run_osc(handle, capbuf, mask);
444 if (ACPI_SUCCESS(status))
445 root->osc_control_set = *mask;
446 out:
447 mutex_unlock(&osc_lock);
448 return status;
449 }
450 EXPORT_SYMBOL(acpi_pci_osc_control_set);
451
acpi_pci_root_add(struct acpi_device * device)452 static int __devinit acpi_pci_root_add(struct acpi_device *device)
453 {
454 unsigned long long segment, bus;
455 acpi_status status;
456 int result;
457 struct acpi_pci_root *root;
458 acpi_handle handle;
459 struct acpi_device *child;
460 u32 flags, base_flags;
461
462 root = kzalloc(sizeof(struct acpi_pci_root), GFP_KERNEL);
463 if (!root)
464 return -ENOMEM;
465
466 segment = 0;
467 status = acpi_evaluate_integer(device->handle, METHOD_NAME__SEG, NULL,
468 &segment);
469 if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
470 printk(KERN_ERR PREFIX "can't evaluate _SEG\n");
471 result = -ENODEV;
472 goto end;
473 }
474
475 /* Check _CRS first, then _BBN. If no _BBN, default to zero. */
476 root->secondary.flags = IORESOURCE_BUS;
477 status = try_get_root_bridge_busnr(device->handle, &root->secondary);
478 if (ACPI_FAILURE(status)) {
479 /*
480 * We need both the start and end of the downstream bus range
481 * to interpret _CBA (MMCONFIG base address), so it really is
482 * supposed to be in _CRS. If we don't find it there, all we
483 * can do is assume [_BBN-0xFF] or [0-0xFF].
484 */
485 root->secondary.end = 0xFF;
486 printk(KERN_WARNING FW_BUG PREFIX
487 "no secondary bus range in _CRS\n");
488 status = acpi_evaluate_integer(device->handle, METHOD_NAME__BBN, NULL, &bus);
489 if (ACPI_SUCCESS(status))
490 root->secondary.start = bus;
491 else if (status == AE_NOT_FOUND)
492 root->secondary.start = 0;
493 else {
494 printk(KERN_ERR PREFIX "can't evaluate _BBN\n");
495 result = -ENODEV;
496 goto end;
497 }
498 }
499
500 INIT_LIST_HEAD(&root->node);
501 root->device = device;
502 root->segment = segment & 0xFFFF;
503 strcpy(acpi_device_name(device), ACPI_PCI_ROOT_DEVICE_NAME);
504 strcpy(acpi_device_class(device), ACPI_PCI_ROOT_CLASS);
505 device->driver_data = root;
506
507 /*
508 * All supported architectures that use ACPI have support for
509 * PCI domains, so we indicate this in _OSC support capabilities.
510 */
511 flags = base_flags = OSC_PCI_SEGMENT_GROUPS_SUPPORT;
512 acpi_pci_osc_support(root, flags);
513
514 /*
515 * TBD: Need PCI interface for enumeration/configuration of roots.
516 */
517
518 /* TBD: Locking */
519 list_add_tail(&root->node, &acpi_pci_roots);
520
521 printk(KERN_INFO PREFIX "%s [%s] (domain %04x %pR)\n",
522 acpi_device_name(device), acpi_device_bid(device),
523 root->segment, &root->secondary);
524
525 /*
526 * Scan the Root Bridge
527 * --------------------
528 * Must do this prior to any attempt to bind the root device, as the
529 * PCI namespace does not get created until this call is made (and
530 * thus the root bridge's pci_dev does not exist).
531 */
532 root->bus = pci_acpi_scan_root(root);
533 if (!root->bus) {
534 printk(KERN_ERR PREFIX
535 "Bus %04x:%02x not present in PCI namespace\n",
536 root->segment, (unsigned int)root->secondary.start);
537 result = -ENODEV;
538 goto end;
539 }
540
541 /*
542 * Attach ACPI-PCI Context
543 * -----------------------
544 * Thus binding the ACPI and PCI devices.
545 */
546 result = acpi_pci_bind_root(device);
547 if (result)
548 goto end;
549
550 /*
551 * PCI Routing Table
552 * -----------------
553 * Evaluate and parse _PRT, if exists.
554 */
555 status = acpi_get_handle(device->handle, METHOD_NAME__PRT, &handle);
556 if (ACPI_SUCCESS(status))
557 result = acpi_pci_irq_add_prt(device->handle, root->bus);
558
559 /*
560 * Scan and bind all _ADR-Based Devices
561 */
562 list_for_each_entry(child, &device->children, node)
563 acpi_pci_bridge_scan(child);
564
565 /* Indicate support for various _OSC capabilities. */
566 if (pci_ext_cfg_avail(root->bus->self))
567 flags |= OSC_EXT_PCI_CONFIG_SUPPORT;
568 if (pcie_aspm_support_enabled())
569 flags |= OSC_ACTIVE_STATE_PWR_SUPPORT |
570 OSC_CLOCK_PWR_CAPABILITY_SUPPORT;
571 if (pci_msi_enabled())
572 flags |= OSC_MSI_SUPPORT;
573 if (flags != base_flags)
574 acpi_pci_osc_support(root, flags);
575
576 if (!pcie_ports_disabled
577 && (flags & ACPI_PCIE_REQ_SUPPORT) == ACPI_PCIE_REQ_SUPPORT) {
578 flags = OSC_PCI_EXPRESS_CAP_STRUCTURE_CONTROL
579 | OSC_PCI_EXPRESS_NATIVE_HP_CONTROL
580 | OSC_PCI_EXPRESS_PME_CONTROL;
581
582 if (pci_aer_available()) {
583 if (aer_acpi_firmware_first())
584 dev_dbg(root->bus->bridge,
585 "PCIe errors handled by BIOS.\n");
586 else
587 flags |= OSC_PCI_EXPRESS_AER_CONTROL;
588 }
589
590 dev_info(root->bus->bridge,
591 "Requesting ACPI _OSC control (0x%02x)\n", flags);
592
593 status = acpi_pci_osc_control_set(device->handle, &flags,
594 OSC_PCI_EXPRESS_CAP_STRUCTURE_CONTROL);
595 if (ACPI_SUCCESS(status)) {
596 dev_info(root->bus->bridge,
597 "ACPI _OSC control (0x%02x) granted\n", flags);
598 } else {
599 dev_dbg(root->bus->bridge,
600 "ACPI _OSC request failed (code %d)\n", status);
601 printk(KERN_INFO "Unable to assume _OSC PCIe control. "
602 "Disabling ASPM\n");
603 pcie_no_aspm();
604 }
605 }
606
607 pci_acpi_add_bus_pm_notifier(device, root->bus);
608 if (device->wakeup.flags.run_wake)
609 device_set_run_wake(root->bus->bridge, true);
610
611 return 0;
612
613 end:
614 if (!list_empty(&root->node))
615 list_del(&root->node);
616 kfree(root);
617 return result;
618 }
619
acpi_pci_root_start(struct acpi_device * device)620 static int acpi_pci_root_start(struct acpi_device *device)
621 {
622 struct acpi_pci_root *root = acpi_driver_data(device);
623
624 pci_bus_add_devices(root->bus);
625 return 0;
626 }
627
acpi_pci_root_remove(struct acpi_device * device,int type)628 static int acpi_pci_root_remove(struct acpi_device *device, int type)
629 {
630 struct acpi_pci_root *root = acpi_driver_data(device);
631
632 device_set_run_wake(root->bus->bridge, false);
633 pci_acpi_remove_bus_pm_notifier(device);
634
635 kfree(root);
636 return 0;
637 }
638
acpi_pci_root_init(void)639 static int __init acpi_pci_root_init(void)
640 {
641 acpi_hest_init();
642
643 if (acpi_pci_disabled)
644 return 0;
645
646 pci_acpi_crs_quirks();
647 if (acpi_bus_register_driver(&acpi_pci_root_driver) < 0)
648 return -ENODEV;
649
650 return 0;
651 }
652
653 subsys_initcall(acpi_pci_root_init);
654