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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
45ACPI_MODULE_NAME("pci_root");
46#define ACPI_PCI_ROOT_CLASS "pci_bridge"
47#define ACPI_PCI_ROOT_DEVICE_NAME "PCI Root Bridge"
48static int acpi_pci_root_add(struct acpi_device *device);
49static int acpi_pci_root_remove(struct acpi_device *device, int type);
50static 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
57static const struct acpi_device_id root_device_ids[] = {
58 {"PNP0A03", 0},
59 {"", 0},
60};
61MODULE_DEVICE_TABLE(acpi, root_device_ids);
62
63static 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
74static LIST_HEAD(acpi_pci_roots);
75
76static struct acpi_pci_driver *sub_driver;
77static DEFINE_MUTEX(osc_lock);
78
79int 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
100EXPORT_SYMBOL(acpi_pci_register_driver);
101
102void 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
122EXPORT_SYMBOL(acpi_pci_unregister_driver);
123
124acpi_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
135EXPORT_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 */
144int 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}
159EXPORT_SYMBOL_GPL(acpi_is_root_bridge);
160
161static acpi_status
162get_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
182static 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
198static 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
213static u8 pci_osc_uuid_str[] = "33DB4D5B-1FF7-401C-9657-7441C03DD766";
214
215static 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
234static 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
263static 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
277struct 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}
287EXPORT_SYMBOL_GPL(acpi_pci_find_root);
288
289struct 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 */
306struct 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 }
373out:
374 list_for_each_entry_safe(node, tmp, &device_list, node)
375 kfree(node);
376
377 return pdev;
378}
379EXPORT_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 **/
396acpi_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;
446out:
447 mutex_unlock(&osc_lock);
448 return status;
449}
450EXPORT_SYMBOL(acpi_pci_osc_control_set);
451
452static 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,
489 NULL, &bus);
490 if (ACPI_SUCCESS(status))
491 root->secondary.start = bus;
492 else if (status == AE_NOT_FOUND)
493 root->secondary.start = 0;
494 else {
495 printk(KERN_ERR PREFIX "can't evaluate _BBN\n");
496 result = -ENODEV;
497 goto end;
498 }
499 }
500
501 INIT_LIST_HEAD(&root->node);
502 root->device = device;
503 root->segment = segment & 0xFFFF;
504 strcpy(acpi_device_name(device), ACPI_PCI_ROOT_DEVICE_NAME);
505 strcpy(acpi_device_class(device), ACPI_PCI_ROOT_CLASS);
506 device->driver_data = root;
507
508 /*
509 * All supported architectures that use ACPI have support for
510 * PCI domains, so we indicate this in _OSC support capabilities.
511 */
512 flags = base_flags = OSC_PCI_SEGMENT_GROUPS_SUPPORT;
513 acpi_pci_osc_support(root, flags);
514
515 /*
516 * TBD: Need PCI interface for enumeration/configuration of roots.
517 */
518
519 /* TBD: Locking */
520 list_add_tail(&root->node, &acpi_pci_roots);
521
522 printk(KERN_INFO PREFIX "%s [%s] (domain %04x %pR)\n",
523 acpi_device_name(device), acpi_device_bid(device),
524 root->segment, &root->secondary);
525
526 /*
527 * Scan the Root Bridge
528 * --------------------
529 * Must do this prior to any attempt to bind the root device, as the
530 * PCI namespace does not get created until this call is made (and
531 * thus the root bridge's pci_dev does not exist).
532 */
533 root->bus = pci_acpi_scan_root(root);
534 if (!root->bus) {
535 printk(KERN_ERR PREFIX
536 "Bus %04x:%02x not present in PCI namespace\n",
537 root->segment, (unsigned int)root->secondary.start);
538 result = -ENODEV;
539 goto end;
540 }
541
542 /*
543 * Attach ACPI-PCI Context
544 * -----------------------
545 * Thus binding the ACPI and PCI devices.
546 */
547 result = acpi_pci_bind_root(device);
548 if (result)
549 goto end;
550
551 /*
552 * PCI Routing Table
553 * -----------------
554 * Evaluate and parse _PRT, if exists.
555 */
556 status = acpi_get_handle(device->handle, METHOD_NAME__PRT, &handle);
557 if (ACPI_SUCCESS(status))
558 result = acpi_pci_irq_add_prt(device->handle, root->bus);
559
560 /*
561 * Scan and bind all _ADR-Based Devices
562 */
563 list_for_each_entry(child, &device->children, node)
564 acpi_pci_bridge_scan(child);
565
566 /* Indicate support for various _OSC capabilities. */
567 if (pci_ext_cfg_avail(root->bus->self))
568 flags |= OSC_EXT_PCI_CONFIG_SUPPORT;
569 if (pcie_aspm_support_enabled())
570 flags |= OSC_ACTIVE_STATE_PWR_SUPPORT |
571 OSC_CLOCK_PWR_CAPABILITY_SUPPORT;
572 if (pci_msi_enabled())
573 flags |= OSC_MSI_SUPPORT;
574 if (flags != base_flags)
575 acpi_pci_osc_support(root, flags);
576
577 if (!pcie_ports_disabled
578 && (flags & ACPI_PCIE_REQ_SUPPORT) == ACPI_PCIE_REQ_SUPPORT) {
579 flags = OSC_PCI_EXPRESS_CAP_STRUCTURE_CONTROL
580 | OSC_PCI_EXPRESS_NATIVE_HP_CONTROL
581 | OSC_PCI_EXPRESS_PME_CONTROL;
582
583 if (pci_aer_available()) {
584 if (aer_acpi_firmware_first())
585 dev_dbg(root->bus->bridge,
586 "PCIe errors handled by BIOS.\n");
587 else
588 flags |= OSC_PCI_EXPRESS_AER_CONTROL;
589 }
590
591 dev_info(root->bus->bridge,
592 "Requesting ACPI _OSC control (0x%02x)\n", flags);
593
594 status = acpi_pci_osc_control_set(device->handle, &flags,
595 OSC_PCI_EXPRESS_CAP_STRUCTURE_CONTROL);
596 if (ACPI_SUCCESS(status)) {
597 dev_info(root->bus->bridge,
598 "ACPI _OSC control (0x%02x) granted\n", flags);
599 } else {
600 dev_info(root->bus->bridge,
601 "ACPI _OSC request failed (%s), "
602 "returned control mask: 0x%02x\n",
603 acpi_format_exception(status), flags);
604 pr_info("ACPI _OSC control for PCIe not granted, "
605 "disabling ASPM\n");
606 pcie_no_aspm();
607 }
608 } else {
609 dev_info(root->bus->bridge,
610 "Unable to request _OSC control "
611 "(_OSC support mask: 0x%02x)\n", flags);
612 }
613
614 pci_acpi_add_bus_pm_notifier(device, root->bus);
615 if (device->wakeup.flags.run_wake)
616 device_set_run_wake(root->bus->bridge, true);
617
618 return 0;
619
620end:
621 if (!list_empty(&root->node))
622 list_del(&root->node);
623 kfree(root);
624 return result;
625}
626
627static int acpi_pci_root_start(struct acpi_device *device)
628{
629 struct acpi_pci_root *root = acpi_driver_data(device);
630
631 pci_bus_add_devices(root->bus);
632 return 0;
633}
634
635static int acpi_pci_root_remove(struct acpi_device *device, int type)
636{
637 struct acpi_pci_root *root = acpi_driver_data(device);
638
639 device_set_run_wake(root->bus->bridge, false);
640 pci_acpi_remove_bus_pm_notifier(device);
641
642 kfree(root);
643 return 0;
644}
645
646static int __init acpi_pci_root_init(void)
647{
648 acpi_hest_init();
649
650 if (acpi_pci_disabled)
651 return 0;
652
653 pci_acpi_crs_quirks();
654 if (acpi_bus_register_driver(&acpi_pci_root_driver) < 0)
655 return -ENODEV;
656
657 return 0;
658}
659
660subsys_initcall(acpi_pci_root_init);
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/mutex.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/apei.h> /* for acpi_hest_init() */
39
40#include "internal.h"
41
42#define _COMPONENT ACPI_PCI_COMPONENT
43ACPI_MODULE_NAME("pci_root");
44#define ACPI_PCI_ROOT_CLASS "pci_bridge"
45#define ACPI_PCI_ROOT_DEVICE_NAME "PCI Root Bridge"
46static int acpi_pci_root_add(struct acpi_device *device,
47 const struct acpi_device_id *not_used);
48static void acpi_pci_root_remove(struct acpi_device *device);
49
50static int acpi_pci_root_scan_dependent(struct acpi_device *adev)
51{
52 acpiphp_check_host_bridge(adev);
53 return 0;
54}
55
56#define ACPI_PCIE_REQ_SUPPORT (OSC_PCI_EXT_CONFIG_SUPPORT \
57 | OSC_PCI_ASPM_SUPPORT \
58 | OSC_PCI_CLOCK_PM_SUPPORT \
59 | OSC_PCI_MSI_SUPPORT)
60
61static const struct acpi_device_id root_device_ids[] = {
62 {"PNP0A03", 0},
63 {"", 0},
64};
65
66static struct acpi_scan_handler pci_root_handler = {
67 .ids = root_device_ids,
68 .attach = acpi_pci_root_add,
69 .detach = acpi_pci_root_remove,
70 .hotplug = {
71 .enabled = true,
72 .scan_dependent = acpi_pci_root_scan_dependent,
73 },
74};
75
76static DEFINE_MUTEX(osc_lock);
77
78/**
79 * acpi_is_root_bridge - determine whether an ACPI CA node is a PCI root bridge
80 * @handle - the ACPI CA node in question.
81 *
82 * Note: we could make this API take a struct acpi_device * instead, but
83 * for now, it's more convenient to operate on an acpi_handle.
84 */
85int acpi_is_root_bridge(acpi_handle handle)
86{
87 int ret;
88 struct acpi_device *device;
89
90 ret = acpi_bus_get_device(handle, &device);
91 if (ret)
92 return 0;
93
94 ret = acpi_match_device_ids(device, root_device_ids);
95 if (ret)
96 return 0;
97 else
98 return 1;
99}
100EXPORT_SYMBOL_GPL(acpi_is_root_bridge);
101
102static acpi_status
103get_root_bridge_busnr_callback(struct acpi_resource *resource, void *data)
104{
105 struct resource *res = data;
106 struct acpi_resource_address64 address;
107 acpi_status status;
108
109 status = acpi_resource_to_address64(resource, &address);
110 if (ACPI_FAILURE(status))
111 return AE_OK;
112
113 if ((address.address_length > 0) &&
114 (address.resource_type == ACPI_BUS_NUMBER_RANGE)) {
115 res->start = address.minimum;
116 res->end = address.minimum + address.address_length - 1;
117 }
118
119 return AE_OK;
120}
121
122static acpi_status try_get_root_bridge_busnr(acpi_handle handle,
123 struct resource *res)
124{
125 acpi_status status;
126
127 res->start = -1;
128 status =
129 acpi_walk_resources(handle, METHOD_NAME__CRS,
130 get_root_bridge_busnr_callback, res);
131 if (ACPI_FAILURE(status))
132 return status;
133 if (res->start == -1)
134 return AE_ERROR;
135 return AE_OK;
136}
137
138struct pci_osc_bit_struct {
139 u32 bit;
140 char *desc;
141};
142
143static struct pci_osc_bit_struct pci_osc_support_bit[] = {
144 { OSC_PCI_EXT_CONFIG_SUPPORT, "ExtendedConfig" },
145 { OSC_PCI_ASPM_SUPPORT, "ASPM" },
146 { OSC_PCI_CLOCK_PM_SUPPORT, "ClockPM" },
147 { OSC_PCI_SEGMENT_GROUPS_SUPPORT, "Segments" },
148 { OSC_PCI_MSI_SUPPORT, "MSI" },
149};
150
151static struct pci_osc_bit_struct pci_osc_control_bit[] = {
152 { OSC_PCI_EXPRESS_NATIVE_HP_CONTROL, "PCIeHotplug" },
153 { OSC_PCI_SHPC_NATIVE_HP_CONTROL, "SHPCHotplug" },
154 { OSC_PCI_EXPRESS_PME_CONTROL, "PME" },
155 { OSC_PCI_EXPRESS_AER_CONTROL, "AER" },
156 { OSC_PCI_EXPRESS_CAPABILITY_CONTROL, "PCIeCapability" },
157};
158
159static void decode_osc_bits(struct acpi_pci_root *root, char *msg, u32 word,
160 struct pci_osc_bit_struct *table, int size)
161{
162 char buf[80];
163 int i, len = 0;
164 struct pci_osc_bit_struct *entry;
165
166 buf[0] = '\0';
167 for (i = 0, entry = table; i < size; i++, entry++)
168 if (word & entry->bit)
169 len += snprintf(buf + len, sizeof(buf) - len, "%s%s",
170 len ? " " : "", entry->desc);
171
172 dev_info(&root->device->dev, "_OSC: %s [%s]\n", msg, buf);
173}
174
175static void decode_osc_support(struct acpi_pci_root *root, char *msg, u32 word)
176{
177 decode_osc_bits(root, msg, word, pci_osc_support_bit,
178 ARRAY_SIZE(pci_osc_support_bit));
179}
180
181static void decode_osc_control(struct acpi_pci_root *root, char *msg, u32 word)
182{
183 decode_osc_bits(root, msg, word, pci_osc_control_bit,
184 ARRAY_SIZE(pci_osc_control_bit));
185}
186
187static u8 pci_osc_uuid_str[] = "33DB4D5B-1FF7-401C-9657-7441C03DD766";
188
189static acpi_status acpi_pci_run_osc(acpi_handle handle,
190 const u32 *capbuf, u32 *retval)
191{
192 struct acpi_osc_context context = {
193 .uuid_str = pci_osc_uuid_str,
194 .rev = 1,
195 .cap.length = 12,
196 .cap.pointer = (void *)capbuf,
197 };
198 acpi_status status;
199
200 status = acpi_run_osc(handle, &context);
201 if (ACPI_SUCCESS(status)) {
202 *retval = *((u32 *)(context.ret.pointer + 8));
203 kfree(context.ret.pointer);
204 }
205 return status;
206}
207
208static acpi_status acpi_pci_query_osc(struct acpi_pci_root *root,
209 u32 support,
210 u32 *control)
211{
212 acpi_status status;
213 u32 result, capbuf[3];
214
215 support &= OSC_PCI_SUPPORT_MASKS;
216 support |= root->osc_support_set;
217
218 capbuf[OSC_QUERY_DWORD] = OSC_QUERY_ENABLE;
219 capbuf[OSC_SUPPORT_DWORD] = support;
220 if (control) {
221 *control &= OSC_PCI_CONTROL_MASKS;
222 capbuf[OSC_CONTROL_DWORD] = *control | root->osc_control_set;
223 } else {
224 /* Run _OSC query only with existing controls. */
225 capbuf[OSC_CONTROL_DWORD] = root->osc_control_set;
226 }
227
228 status = acpi_pci_run_osc(root->device->handle, capbuf, &result);
229 if (ACPI_SUCCESS(status)) {
230 root->osc_support_set = support;
231 if (control)
232 *control = result;
233 }
234 return status;
235}
236
237static acpi_status acpi_pci_osc_support(struct acpi_pci_root *root, u32 flags)
238{
239 acpi_status status;
240
241 mutex_lock(&osc_lock);
242 status = acpi_pci_query_osc(root, flags, NULL);
243 mutex_unlock(&osc_lock);
244 return status;
245}
246
247struct acpi_pci_root *acpi_pci_find_root(acpi_handle handle)
248{
249 struct acpi_pci_root *root;
250 struct acpi_device *device;
251
252 if (acpi_bus_get_device(handle, &device) ||
253 acpi_match_device_ids(device, root_device_ids))
254 return NULL;
255
256 root = acpi_driver_data(device);
257
258 return root;
259}
260EXPORT_SYMBOL_GPL(acpi_pci_find_root);
261
262struct acpi_handle_node {
263 struct list_head node;
264 acpi_handle handle;
265};
266
267/**
268 * acpi_get_pci_dev - convert ACPI CA handle to struct pci_dev
269 * @handle: the handle in question
270 *
271 * Given an ACPI CA handle, the desired PCI device is located in the
272 * list of PCI devices.
273 *
274 * If the device is found, its reference count is increased and this
275 * function returns a pointer to its data structure. The caller must
276 * decrement the reference count by calling pci_dev_put().
277 * If no device is found, %NULL is returned.
278 */
279struct pci_dev *acpi_get_pci_dev(acpi_handle handle)
280{
281 int dev, fn;
282 unsigned long long adr;
283 acpi_status status;
284 acpi_handle phandle;
285 struct pci_bus *pbus;
286 struct pci_dev *pdev = NULL;
287 struct acpi_handle_node *node, *tmp;
288 struct acpi_pci_root *root;
289 LIST_HEAD(device_list);
290
291 /*
292 * Walk up the ACPI CA namespace until we reach a PCI root bridge.
293 */
294 phandle = handle;
295 while (!acpi_is_root_bridge(phandle)) {
296 node = kzalloc(sizeof(struct acpi_handle_node), GFP_KERNEL);
297 if (!node)
298 goto out;
299
300 INIT_LIST_HEAD(&node->node);
301 node->handle = phandle;
302 list_add(&node->node, &device_list);
303
304 status = acpi_get_parent(phandle, &phandle);
305 if (ACPI_FAILURE(status))
306 goto out;
307 }
308
309 root = acpi_pci_find_root(phandle);
310 if (!root)
311 goto out;
312
313 pbus = root->bus;
314
315 /*
316 * Now, walk back down the PCI device tree until we return to our
317 * original handle. Assumes that everything between the PCI root
318 * bridge and the device we're looking for must be a P2P bridge.
319 */
320 list_for_each_entry(node, &device_list, node) {
321 acpi_handle hnd = node->handle;
322 status = acpi_evaluate_integer(hnd, "_ADR", NULL, &adr);
323 if (ACPI_FAILURE(status))
324 goto out;
325 dev = (adr >> 16) & 0xffff;
326 fn = adr & 0xffff;
327
328 pdev = pci_get_slot(pbus, PCI_DEVFN(dev, fn));
329 if (!pdev || hnd == handle)
330 break;
331
332 pbus = pdev->subordinate;
333 pci_dev_put(pdev);
334
335 /*
336 * This function may be called for a non-PCI device that has a
337 * PCI parent (eg. a disk under a PCI SATA controller). In that
338 * case pdev->subordinate will be NULL for the parent.
339 */
340 if (!pbus) {
341 dev_dbg(&pdev->dev, "Not a PCI-to-PCI bridge\n");
342 pdev = NULL;
343 break;
344 }
345 }
346out:
347 list_for_each_entry_safe(node, tmp, &device_list, node)
348 kfree(node);
349
350 return pdev;
351}
352EXPORT_SYMBOL_GPL(acpi_get_pci_dev);
353
354/**
355 * acpi_pci_osc_control_set - Request control of PCI root _OSC features.
356 * @handle: ACPI handle of a PCI root bridge (or PCIe Root Complex).
357 * @mask: Mask of _OSC bits to request control of, place to store control mask.
358 * @req: Mask of _OSC bits the control of is essential to the caller.
359 *
360 * Run _OSC query for @mask and if that is successful, compare the returned
361 * mask of control bits with @req. If all of the @req bits are set in the
362 * returned mask, run _OSC request for it.
363 *
364 * The variable at the @mask address may be modified regardless of whether or
365 * not the function returns success. On success it will contain the mask of
366 * _OSC bits the BIOS has granted control of, but its contents are meaningless
367 * on failure.
368 **/
369acpi_status acpi_pci_osc_control_set(acpi_handle handle, u32 *mask, u32 req)
370{
371 struct acpi_pci_root *root;
372 acpi_status status = AE_OK;
373 u32 ctrl, capbuf[3];
374
375 if (!mask)
376 return AE_BAD_PARAMETER;
377
378 ctrl = *mask & OSC_PCI_CONTROL_MASKS;
379 if ((ctrl & req) != req)
380 return AE_TYPE;
381
382 root = acpi_pci_find_root(handle);
383 if (!root)
384 return AE_NOT_EXIST;
385
386 mutex_lock(&osc_lock);
387
388 *mask = ctrl | root->osc_control_set;
389 /* No need to evaluate _OSC if the control was already granted. */
390 if ((root->osc_control_set & ctrl) == ctrl)
391 goto out;
392
393 /* Need to check the available controls bits before requesting them. */
394 while (*mask) {
395 status = acpi_pci_query_osc(root, root->osc_support_set, mask);
396 if (ACPI_FAILURE(status))
397 goto out;
398 if (ctrl == *mask)
399 break;
400 decode_osc_control(root, "platform does not support",
401 ctrl & ~(*mask));
402 ctrl = *mask;
403 }
404
405 if ((ctrl & req) != req) {
406 decode_osc_control(root, "not requesting control; platform does not support",
407 req & ~(ctrl));
408 status = AE_SUPPORT;
409 goto out;
410 }
411
412 capbuf[OSC_QUERY_DWORD] = 0;
413 capbuf[OSC_SUPPORT_DWORD] = root->osc_support_set;
414 capbuf[OSC_CONTROL_DWORD] = ctrl;
415 status = acpi_pci_run_osc(handle, capbuf, mask);
416 if (ACPI_SUCCESS(status))
417 root->osc_control_set = *mask;
418out:
419 mutex_unlock(&osc_lock);
420 return status;
421}
422EXPORT_SYMBOL(acpi_pci_osc_control_set);
423
424static void negotiate_os_control(struct acpi_pci_root *root, int *no_aspm,
425 int *clear_aspm)
426{
427 u32 support, control, requested;
428 acpi_status status;
429 struct acpi_device *device = root->device;
430 acpi_handle handle = device->handle;
431
432 /*
433 * All supported architectures that use ACPI have support for
434 * PCI domains, so we indicate this in _OSC support capabilities.
435 */
436 support = OSC_PCI_SEGMENT_GROUPS_SUPPORT;
437 if (pci_ext_cfg_avail())
438 support |= OSC_PCI_EXT_CONFIG_SUPPORT;
439 if (pcie_aspm_support_enabled())
440 support |= OSC_PCI_ASPM_SUPPORT | OSC_PCI_CLOCK_PM_SUPPORT;
441 if (pci_msi_enabled())
442 support |= OSC_PCI_MSI_SUPPORT;
443
444 decode_osc_support(root, "OS supports", support);
445 status = acpi_pci_osc_support(root, support);
446 if (ACPI_FAILURE(status)) {
447 dev_info(&device->dev, "_OSC failed (%s); disabling ASPM\n",
448 acpi_format_exception(status));
449 *no_aspm = 1;
450 return;
451 }
452
453 if (pcie_ports_disabled) {
454 dev_info(&device->dev, "PCIe port services disabled; not requesting _OSC control\n");
455 return;
456 }
457
458 if ((support & ACPI_PCIE_REQ_SUPPORT) != ACPI_PCIE_REQ_SUPPORT) {
459 decode_osc_support(root, "not requesting OS control; OS requires",
460 ACPI_PCIE_REQ_SUPPORT);
461 return;
462 }
463
464 control = OSC_PCI_EXPRESS_CAPABILITY_CONTROL
465 | OSC_PCI_EXPRESS_NATIVE_HP_CONTROL
466 | OSC_PCI_EXPRESS_PME_CONTROL;
467
468 if (pci_aer_available()) {
469 if (aer_acpi_firmware_first())
470 dev_info(&device->dev,
471 "PCIe AER handled by firmware\n");
472 else
473 control |= OSC_PCI_EXPRESS_AER_CONTROL;
474 }
475
476 requested = control;
477 status = acpi_pci_osc_control_set(handle, &control,
478 OSC_PCI_EXPRESS_CAPABILITY_CONTROL);
479 if (ACPI_SUCCESS(status)) {
480 decode_osc_control(root, "OS now controls", control);
481 if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_ASPM) {
482 /*
483 * We have ASPM control, but the FADT indicates
484 * that it's unsupported. Clear it.
485 */
486 *clear_aspm = 1;
487 }
488 } else {
489 decode_osc_control(root, "OS requested", requested);
490 decode_osc_control(root, "platform willing to grant", control);
491 dev_info(&device->dev, "_OSC failed (%s); disabling ASPM\n",
492 acpi_format_exception(status));
493
494 /*
495 * We want to disable ASPM here, but aspm_disabled
496 * needs to remain in its state from boot so that we
497 * properly handle PCIe 1.1 devices. So we set this
498 * flag here, to defer the action until after the ACPI
499 * root scan.
500 */
501 *no_aspm = 1;
502 }
503}
504
505static int acpi_pci_root_add(struct acpi_device *device,
506 const struct acpi_device_id *not_used)
507{
508 unsigned long long segment, bus;
509 acpi_status status;
510 int result;
511 struct acpi_pci_root *root;
512 acpi_handle handle = device->handle;
513 int no_aspm = 0, clear_aspm = 0;
514
515 root = kzalloc(sizeof(struct acpi_pci_root), GFP_KERNEL);
516 if (!root)
517 return -ENOMEM;
518
519 segment = 0;
520 status = acpi_evaluate_integer(handle, METHOD_NAME__SEG, NULL,
521 &segment);
522 if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
523 dev_err(&device->dev, "can't evaluate _SEG\n");
524 result = -ENODEV;
525 goto end;
526 }
527
528 /* Check _CRS first, then _BBN. If no _BBN, default to zero. */
529 root->secondary.flags = IORESOURCE_BUS;
530 status = try_get_root_bridge_busnr(handle, &root->secondary);
531 if (ACPI_FAILURE(status)) {
532 /*
533 * We need both the start and end of the downstream bus range
534 * to interpret _CBA (MMCONFIG base address), so it really is
535 * supposed to be in _CRS. If we don't find it there, all we
536 * can do is assume [_BBN-0xFF] or [0-0xFF].
537 */
538 root->secondary.end = 0xFF;
539 dev_warn(&device->dev,
540 FW_BUG "no secondary bus range in _CRS\n");
541 status = acpi_evaluate_integer(handle, METHOD_NAME__BBN,
542 NULL, &bus);
543 if (ACPI_SUCCESS(status))
544 root->secondary.start = bus;
545 else if (status == AE_NOT_FOUND)
546 root->secondary.start = 0;
547 else {
548 dev_err(&device->dev, "can't evaluate _BBN\n");
549 result = -ENODEV;
550 goto end;
551 }
552 }
553
554 root->device = device;
555 root->segment = segment & 0xFFFF;
556 strcpy(acpi_device_name(device), ACPI_PCI_ROOT_DEVICE_NAME);
557 strcpy(acpi_device_class(device), ACPI_PCI_ROOT_CLASS);
558 device->driver_data = root;
559
560 pr_info(PREFIX "%s [%s] (domain %04x %pR)\n",
561 acpi_device_name(device), acpi_device_bid(device),
562 root->segment, &root->secondary);
563
564 root->mcfg_addr = acpi_pci_root_get_mcfg_addr(handle);
565
566 negotiate_os_control(root, &no_aspm, &clear_aspm);
567
568 /*
569 * TBD: Need PCI interface for enumeration/configuration of roots.
570 */
571
572 /*
573 * Scan the Root Bridge
574 * --------------------
575 * Must do this prior to any attempt to bind the root device, as the
576 * PCI namespace does not get created until this call is made (and
577 * thus the root bridge's pci_dev does not exist).
578 */
579 root->bus = pci_acpi_scan_root(root);
580 if (!root->bus) {
581 dev_err(&device->dev,
582 "Bus %04x:%02x not present in PCI namespace\n",
583 root->segment, (unsigned int)root->secondary.start);
584 device->driver_data = NULL;
585 result = -ENODEV;
586 goto end;
587 }
588
589 if (clear_aspm) {
590 dev_info(&device->dev, "Disabling ASPM (FADT indicates it is unsupported)\n");
591 pcie_clear_aspm(root->bus);
592 }
593 if (no_aspm)
594 pcie_no_aspm();
595
596 pci_acpi_add_bus_pm_notifier(device, root->bus);
597 if (device->wakeup.flags.run_wake)
598 device_set_run_wake(root->bus->bridge, true);
599
600 if (system_state != SYSTEM_BOOTING) {
601 pcibios_resource_survey_bus(root->bus);
602 pci_assign_unassigned_root_bus_resources(root->bus);
603 }
604
605 pci_lock_rescan_remove();
606 pci_bus_add_devices(root->bus);
607 pci_unlock_rescan_remove();
608 return 1;
609
610end:
611 kfree(root);
612 return result;
613}
614
615static void acpi_pci_root_remove(struct acpi_device *device)
616{
617 struct acpi_pci_root *root = acpi_driver_data(device);
618
619 pci_lock_rescan_remove();
620
621 pci_stop_root_bus(root->bus);
622
623 device_set_run_wake(root->bus->bridge, false);
624 pci_acpi_remove_bus_pm_notifier(device);
625
626 pci_remove_root_bus(root->bus);
627
628 pci_unlock_rescan_remove();
629
630 kfree(root);
631}
632
633void __init acpi_pci_root_init(void)
634{
635 acpi_hest_init();
636 if (acpi_pci_disabled)
637 return;
638
639 pci_acpi_crs_quirks();
640 acpi_scan_add_handler_with_hotplug(&pci_root_handler, "pci_root");
641}