Loading...
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * pci_root.c - ACPI PCI Root Bridge Driver ($Revision: 40 $)
4 *
5 * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
6 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
7 */
8
9#include <linux/kernel.h>
10#include <linux/module.h>
11#include <linux/init.h>
12#include <linux/types.h>
13#include <linux/mutex.h>
14#include <linux/pm.h>
15#include <linux/pm_runtime.h>
16#include <linux/pci.h>
17#include <linux/pci-acpi.h>
18#include <linux/dmar.h>
19#include <linux/acpi.h>
20#include <linux/slab.h>
21#include <linux/dmi.h>
22#include <linux/platform_data/x86/apple.h>
23#include <acpi/apei.h> /* for acpi_hest_init() */
24
25#include "internal.h"
26
27#define _COMPONENT ACPI_PCI_COMPONENT
28ACPI_MODULE_NAME("pci_root");
29#define ACPI_PCI_ROOT_CLASS "pci_bridge"
30#define ACPI_PCI_ROOT_DEVICE_NAME "PCI Root Bridge"
31static int acpi_pci_root_add(struct acpi_device *device,
32 const struct acpi_device_id *not_used);
33static void acpi_pci_root_remove(struct acpi_device *device);
34
35static int acpi_pci_root_scan_dependent(struct acpi_device *adev)
36{
37 acpiphp_check_host_bridge(adev);
38 return 0;
39}
40
41#define ACPI_PCIE_REQ_SUPPORT (OSC_PCI_EXT_CONFIG_SUPPORT \
42 | OSC_PCI_ASPM_SUPPORT \
43 | OSC_PCI_CLOCK_PM_SUPPORT \
44 | OSC_PCI_MSI_SUPPORT)
45
46static const struct acpi_device_id root_device_ids[] = {
47 {"PNP0A03", 0},
48 {"", 0},
49};
50
51static struct acpi_scan_handler pci_root_handler = {
52 .ids = root_device_ids,
53 .attach = acpi_pci_root_add,
54 .detach = acpi_pci_root_remove,
55 .hotplug = {
56 .enabled = true,
57 .scan_dependent = acpi_pci_root_scan_dependent,
58 },
59};
60
61static DEFINE_MUTEX(osc_lock);
62
63/**
64 * acpi_is_root_bridge - determine whether an ACPI CA node is a PCI root bridge
65 * @handle - the ACPI CA node in question.
66 *
67 * Note: we could make this API take a struct acpi_device * instead, but
68 * for now, it's more convenient to operate on an acpi_handle.
69 */
70int acpi_is_root_bridge(acpi_handle handle)
71{
72 int ret;
73 struct acpi_device *device;
74
75 ret = acpi_bus_get_device(handle, &device);
76 if (ret)
77 return 0;
78
79 ret = acpi_match_device_ids(device, root_device_ids);
80 if (ret)
81 return 0;
82 else
83 return 1;
84}
85EXPORT_SYMBOL_GPL(acpi_is_root_bridge);
86
87static acpi_status
88get_root_bridge_busnr_callback(struct acpi_resource *resource, void *data)
89{
90 struct resource *res = data;
91 struct acpi_resource_address64 address;
92 acpi_status status;
93
94 status = acpi_resource_to_address64(resource, &address);
95 if (ACPI_FAILURE(status))
96 return AE_OK;
97
98 if ((address.address.address_length > 0) &&
99 (address.resource_type == ACPI_BUS_NUMBER_RANGE)) {
100 res->start = address.address.minimum;
101 res->end = address.address.minimum + address.address.address_length - 1;
102 }
103
104 return AE_OK;
105}
106
107static acpi_status try_get_root_bridge_busnr(acpi_handle handle,
108 struct resource *res)
109{
110 acpi_status status;
111
112 res->start = -1;
113 status =
114 acpi_walk_resources(handle, METHOD_NAME__CRS,
115 get_root_bridge_busnr_callback, res);
116 if (ACPI_FAILURE(status))
117 return status;
118 if (res->start == -1)
119 return AE_ERROR;
120 return AE_OK;
121}
122
123struct pci_osc_bit_struct {
124 u32 bit;
125 char *desc;
126};
127
128static struct pci_osc_bit_struct pci_osc_support_bit[] = {
129 { OSC_PCI_EXT_CONFIG_SUPPORT, "ExtendedConfig" },
130 { OSC_PCI_ASPM_SUPPORT, "ASPM" },
131 { OSC_PCI_CLOCK_PM_SUPPORT, "ClockPM" },
132 { OSC_PCI_SEGMENT_GROUPS_SUPPORT, "Segments" },
133 { OSC_PCI_MSI_SUPPORT, "MSI" },
134 { OSC_PCI_HPX_TYPE_3_SUPPORT, "HPX-Type3" },
135};
136
137static struct pci_osc_bit_struct pci_osc_control_bit[] = {
138 { OSC_PCI_EXPRESS_NATIVE_HP_CONTROL, "PCIeHotplug" },
139 { OSC_PCI_SHPC_NATIVE_HP_CONTROL, "SHPCHotplug" },
140 { OSC_PCI_EXPRESS_PME_CONTROL, "PME" },
141 { OSC_PCI_EXPRESS_AER_CONTROL, "AER" },
142 { OSC_PCI_EXPRESS_CAPABILITY_CONTROL, "PCIeCapability" },
143 { OSC_PCI_EXPRESS_LTR_CONTROL, "LTR" },
144};
145
146static void decode_osc_bits(struct acpi_pci_root *root, char *msg, u32 word,
147 struct pci_osc_bit_struct *table, int size)
148{
149 char buf[80];
150 int i, len = 0;
151 struct pci_osc_bit_struct *entry;
152
153 buf[0] = '\0';
154 for (i = 0, entry = table; i < size; i++, entry++)
155 if (word & entry->bit)
156 len += snprintf(buf + len, sizeof(buf) - len, "%s%s",
157 len ? " " : "", entry->desc);
158
159 dev_info(&root->device->dev, "_OSC: %s [%s]\n", msg, buf);
160}
161
162static void decode_osc_support(struct acpi_pci_root *root, char *msg, u32 word)
163{
164 decode_osc_bits(root, msg, word, pci_osc_support_bit,
165 ARRAY_SIZE(pci_osc_support_bit));
166}
167
168static void decode_osc_control(struct acpi_pci_root *root, char *msg, u32 word)
169{
170 decode_osc_bits(root, msg, word, pci_osc_control_bit,
171 ARRAY_SIZE(pci_osc_control_bit));
172}
173
174static u8 pci_osc_uuid_str[] = "33DB4D5B-1FF7-401C-9657-7441C03DD766";
175
176static acpi_status acpi_pci_run_osc(acpi_handle handle,
177 const u32 *capbuf, u32 *retval)
178{
179 struct acpi_osc_context context = {
180 .uuid_str = pci_osc_uuid_str,
181 .rev = 1,
182 .cap.length = 12,
183 .cap.pointer = (void *)capbuf,
184 };
185 acpi_status status;
186
187 status = acpi_run_osc(handle, &context);
188 if (ACPI_SUCCESS(status)) {
189 *retval = *((u32 *)(context.ret.pointer + 8));
190 kfree(context.ret.pointer);
191 }
192 return status;
193}
194
195static acpi_status acpi_pci_query_osc(struct acpi_pci_root *root,
196 u32 support,
197 u32 *control)
198{
199 acpi_status status;
200 u32 result, capbuf[3];
201
202 support &= OSC_PCI_SUPPORT_MASKS;
203 support |= root->osc_support_set;
204
205 capbuf[OSC_QUERY_DWORD] = OSC_QUERY_ENABLE;
206 capbuf[OSC_SUPPORT_DWORD] = support;
207 if (control) {
208 *control &= OSC_PCI_CONTROL_MASKS;
209 capbuf[OSC_CONTROL_DWORD] = *control | root->osc_control_set;
210 } else {
211 /* Run _OSC query only with existing controls. */
212 capbuf[OSC_CONTROL_DWORD] = root->osc_control_set;
213 }
214
215 status = acpi_pci_run_osc(root->device->handle, capbuf, &result);
216 if (ACPI_SUCCESS(status)) {
217 root->osc_support_set = support;
218 if (control)
219 *control = result;
220 }
221 return status;
222}
223
224static acpi_status acpi_pci_osc_support(struct acpi_pci_root *root, u32 flags)
225{
226 acpi_status status;
227
228 mutex_lock(&osc_lock);
229 status = acpi_pci_query_osc(root, flags, NULL);
230 mutex_unlock(&osc_lock);
231 return status;
232}
233
234struct acpi_pci_root *acpi_pci_find_root(acpi_handle handle)
235{
236 struct acpi_pci_root *root;
237 struct acpi_device *device;
238
239 if (acpi_bus_get_device(handle, &device) ||
240 acpi_match_device_ids(device, root_device_ids))
241 return NULL;
242
243 root = acpi_driver_data(device);
244
245 return root;
246}
247EXPORT_SYMBOL_GPL(acpi_pci_find_root);
248
249struct acpi_handle_node {
250 struct list_head node;
251 acpi_handle handle;
252};
253
254/**
255 * acpi_get_pci_dev - convert ACPI CA handle to struct pci_dev
256 * @handle: the handle in question
257 *
258 * Given an ACPI CA handle, the desired PCI device is located in the
259 * list of PCI devices.
260 *
261 * If the device is found, its reference count is increased and this
262 * function returns a pointer to its data structure. The caller must
263 * decrement the reference count by calling pci_dev_put().
264 * If no device is found, %NULL is returned.
265 */
266struct pci_dev *acpi_get_pci_dev(acpi_handle handle)
267{
268 int dev, fn;
269 unsigned long long adr;
270 acpi_status status;
271 acpi_handle phandle;
272 struct pci_bus *pbus;
273 struct pci_dev *pdev = NULL;
274 struct acpi_handle_node *node, *tmp;
275 struct acpi_pci_root *root;
276 LIST_HEAD(device_list);
277
278 /*
279 * Walk up the ACPI CA namespace until we reach a PCI root bridge.
280 */
281 phandle = handle;
282 while (!acpi_is_root_bridge(phandle)) {
283 node = kzalloc(sizeof(struct acpi_handle_node), GFP_KERNEL);
284 if (!node)
285 goto out;
286
287 INIT_LIST_HEAD(&node->node);
288 node->handle = phandle;
289 list_add(&node->node, &device_list);
290
291 status = acpi_get_parent(phandle, &phandle);
292 if (ACPI_FAILURE(status))
293 goto out;
294 }
295
296 root = acpi_pci_find_root(phandle);
297 if (!root)
298 goto out;
299
300 pbus = root->bus;
301
302 /*
303 * Now, walk back down the PCI device tree until we return to our
304 * original handle. Assumes that everything between the PCI root
305 * bridge and the device we're looking for must be a P2P bridge.
306 */
307 list_for_each_entry(node, &device_list, node) {
308 acpi_handle hnd = node->handle;
309 status = acpi_evaluate_integer(hnd, "_ADR", NULL, &adr);
310 if (ACPI_FAILURE(status))
311 goto out;
312 dev = (adr >> 16) & 0xffff;
313 fn = adr & 0xffff;
314
315 pdev = pci_get_slot(pbus, PCI_DEVFN(dev, fn));
316 if (!pdev || hnd == handle)
317 break;
318
319 pbus = pdev->subordinate;
320 pci_dev_put(pdev);
321
322 /*
323 * This function may be called for a non-PCI device that has a
324 * PCI parent (eg. a disk under a PCI SATA controller). In that
325 * case pdev->subordinate will be NULL for the parent.
326 */
327 if (!pbus) {
328 dev_dbg(&pdev->dev, "Not a PCI-to-PCI bridge\n");
329 pdev = NULL;
330 break;
331 }
332 }
333out:
334 list_for_each_entry_safe(node, tmp, &device_list, node)
335 kfree(node);
336
337 return pdev;
338}
339EXPORT_SYMBOL_GPL(acpi_get_pci_dev);
340
341/**
342 * acpi_pci_osc_control_set - Request control of PCI root _OSC features.
343 * @handle: ACPI handle of a PCI root bridge (or PCIe Root Complex).
344 * @mask: Mask of _OSC bits to request control of, place to store control mask.
345 * @req: Mask of _OSC bits the control of is essential to the caller.
346 *
347 * Run _OSC query for @mask and if that is successful, compare the returned
348 * mask of control bits with @req. If all of the @req bits are set in the
349 * returned mask, run _OSC request for it.
350 *
351 * The variable at the @mask address may be modified regardless of whether or
352 * not the function returns success. On success it will contain the mask of
353 * _OSC bits the BIOS has granted control of, but its contents are meaningless
354 * on failure.
355 **/
356acpi_status acpi_pci_osc_control_set(acpi_handle handle, u32 *mask, u32 req)
357{
358 struct acpi_pci_root *root;
359 acpi_status status = AE_OK;
360 u32 ctrl, capbuf[3];
361
362 if (!mask)
363 return AE_BAD_PARAMETER;
364
365 ctrl = *mask & OSC_PCI_CONTROL_MASKS;
366 if ((ctrl & req) != req)
367 return AE_TYPE;
368
369 root = acpi_pci_find_root(handle);
370 if (!root)
371 return AE_NOT_EXIST;
372
373 mutex_lock(&osc_lock);
374
375 *mask = ctrl | root->osc_control_set;
376 /* No need to evaluate _OSC if the control was already granted. */
377 if ((root->osc_control_set & ctrl) == ctrl)
378 goto out;
379
380 /* Need to check the available controls bits before requesting them. */
381 while (*mask) {
382 status = acpi_pci_query_osc(root, root->osc_support_set, mask);
383 if (ACPI_FAILURE(status))
384 goto out;
385 if (ctrl == *mask)
386 break;
387 decode_osc_control(root, "platform does not support",
388 ctrl & ~(*mask));
389 ctrl = *mask;
390 }
391
392 if ((ctrl & req) != req) {
393 decode_osc_control(root, "not requesting control; platform does not support",
394 req & ~(ctrl));
395 status = AE_SUPPORT;
396 goto out;
397 }
398
399 capbuf[OSC_QUERY_DWORD] = 0;
400 capbuf[OSC_SUPPORT_DWORD] = root->osc_support_set;
401 capbuf[OSC_CONTROL_DWORD] = ctrl;
402 status = acpi_pci_run_osc(handle, capbuf, mask);
403 if (ACPI_SUCCESS(status))
404 root->osc_control_set = *mask;
405out:
406 mutex_unlock(&osc_lock);
407 return status;
408}
409EXPORT_SYMBOL(acpi_pci_osc_control_set);
410
411static void negotiate_os_control(struct acpi_pci_root *root, int *no_aspm,
412 bool is_pcie)
413{
414 u32 support, control, requested;
415 acpi_status status;
416 struct acpi_device *device = root->device;
417 acpi_handle handle = device->handle;
418
419 /*
420 * Apple always return failure on _OSC calls when _OSI("Darwin") has
421 * been called successfully. We know the feature set supported by the
422 * platform, so avoid calling _OSC at all
423 */
424 if (x86_apple_machine) {
425 root->osc_control_set = ~OSC_PCI_EXPRESS_PME_CONTROL;
426 decode_osc_control(root, "OS assumes control of",
427 root->osc_control_set);
428 return;
429 }
430
431 /*
432 * All supported architectures that use ACPI have support for
433 * PCI domains, so we indicate this in _OSC support capabilities.
434 */
435 support = OSC_PCI_SEGMENT_GROUPS_SUPPORT;
436 support |= OSC_PCI_HPX_TYPE_3_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 *no_aspm = 1;
448
449 /* _OSC is optional for PCI host bridges */
450 if ((status == AE_NOT_FOUND) && !is_pcie)
451 return;
452
453 dev_info(&device->dev, "_OSC failed (%s)%s\n",
454 acpi_format_exception(status),
455 pcie_aspm_support_enabled() ? "; disabling ASPM" : "");
456 return;
457 }
458
459 if (pcie_ports_disabled) {
460 dev_info(&device->dev, "PCIe port services disabled; not requesting _OSC control\n");
461 return;
462 }
463
464 if ((support & ACPI_PCIE_REQ_SUPPORT) != ACPI_PCIE_REQ_SUPPORT) {
465 decode_osc_support(root, "not requesting OS control; OS requires",
466 ACPI_PCIE_REQ_SUPPORT);
467 return;
468 }
469
470 control = OSC_PCI_EXPRESS_CAPABILITY_CONTROL
471 | OSC_PCI_EXPRESS_PME_CONTROL;
472
473 if (IS_ENABLED(CONFIG_PCIEASPM))
474 control |= OSC_PCI_EXPRESS_LTR_CONTROL;
475
476 if (IS_ENABLED(CONFIG_HOTPLUG_PCI_PCIE))
477 control |= OSC_PCI_EXPRESS_NATIVE_HP_CONTROL;
478
479 if (IS_ENABLED(CONFIG_HOTPLUG_PCI_SHPC))
480 control |= OSC_PCI_SHPC_NATIVE_HP_CONTROL;
481
482 if (pci_aer_available()) {
483 if (aer_acpi_firmware_first())
484 dev_info(&device->dev,
485 "PCIe AER handled by firmware\n");
486 else
487 control |= OSC_PCI_EXPRESS_AER_CONTROL;
488 }
489
490 requested = control;
491 status = acpi_pci_osc_control_set(handle, &control,
492 OSC_PCI_EXPRESS_CAPABILITY_CONTROL);
493 if (ACPI_SUCCESS(status)) {
494 decode_osc_control(root, "OS now controls", control);
495 if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_ASPM) {
496 /*
497 * We have ASPM control, but the FADT indicates that
498 * it's unsupported. Leave existing configuration
499 * intact and prevent the OS from touching it.
500 */
501 dev_info(&device->dev, "FADT indicates ASPM is unsupported, using BIOS configuration\n");
502 *no_aspm = 1;
503 }
504 } else {
505 decode_osc_control(root, "OS requested", requested);
506 decode_osc_control(root, "platform willing to grant", control);
507 dev_info(&device->dev, "_OSC failed (%s); disabling ASPM\n",
508 acpi_format_exception(status));
509
510 /*
511 * We want to disable ASPM here, but aspm_disabled
512 * needs to remain in its state from boot so that we
513 * properly handle PCIe 1.1 devices. So we set this
514 * flag here, to defer the action until after the ACPI
515 * root scan.
516 */
517 *no_aspm = 1;
518 }
519}
520
521static int acpi_pci_root_add(struct acpi_device *device,
522 const struct acpi_device_id *not_used)
523{
524 unsigned long long segment, bus;
525 acpi_status status;
526 int result;
527 struct acpi_pci_root *root;
528 acpi_handle handle = device->handle;
529 int no_aspm = 0;
530 bool hotadd = system_state == SYSTEM_RUNNING;
531 bool is_pcie;
532
533 root = kzalloc(sizeof(struct acpi_pci_root), GFP_KERNEL);
534 if (!root)
535 return -ENOMEM;
536
537 segment = 0;
538 status = acpi_evaluate_integer(handle, METHOD_NAME__SEG, NULL,
539 &segment);
540 if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
541 dev_err(&device->dev, "can't evaluate _SEG\n");
542 result = -ENODEV;
543 goto end;
544 }
545
546 /* Check _CRS first, then _BBN. If no _BBN, default to zero. */
547 root->secondary.flags = IORESOURCE_BUS;
548 status = try_get_root_bridge_busnr(handle, &root->secondary);
549 if (ACPI_FAILURE(status)) {
550 /*
551 * We need both the start and end of the downstream bus range
552 * to interpret _CBA (MMCONFIG base address), so it really is
553 * supposed to be in _CRS. If we don't find it there, all we
554 * can do is assume [_BBN-0xFF] or [0-0xFF].
555 */
556 root->secondary.end = 0xFF;
557 dev_warn(&device->dev,
558 FW_BUG "no secondary bus range in _CRS\n");
559 status = acpi_evaluate_integer(handle, METHOD_NAME__BBN,
560 NULL, &bus);
561 if (ACPI_SUCCESS(status))
562 root->secondary.start = bus;
563 else if (status == AE_NOT_FOUND)
564 root->secondary.start = 0;
565 else {
566 dev_err(&device->dev, "can't evaluate _BBN\n");
567 result = -ENODEV;
568 goto end;
569 }
570 }
571
572 root->device = device;
573 root->segment = segment & 0xFFFF;
574 strcpy(acpi_device_name(device), ACPI_PCI_ROOT_DEVICE_NAME);
575 strcpy(acpi_device_class(device), ACPI_PCI_ROOT_CLASS);
576 device->driver_data = root;
577
578 if (hotadd && dmar_device_add(handle)) {
579 result = -ENXIO;
580 goto end;
581 }
582
583 pr_info(PREFIX "%s [%s] (domain %04x %pR)\n",
584 acpi_device_name(device), acpi_device_bid(device),
585 root->segment, &root->secondary);
586
587 root->mcfg_addr = acpi_pci_root_get_mcfg_addr(handle);
588
589 is_pcie = strcmp(acpi_device_hid(device), "PNP0A08") == 0;
590 negotiate_os_control(root, &no_aspm, is_pcie);
591
592 /*
593 * TBD: Need PCI interface for enumeration/configuration of roots.
594 */
595
596 /*
597 * Scan the Root Bridge
598 * --------------------
599 * Must do this prior to any attempt to bind the root device, as the
600 * PCI namespace does not get created until this call is made (and
601 * thus the root bridge's pci_dev does not exist).
602 */
603 root->bus = pci_acpi_scan_root(root);
604 if (!root->bus) {
605 dev_err(&device->dev,
606 "Bus %04x:%02x not present in PCI namespace\n",
607 root->segment, (unsigned int)root->secondary.start);
608 device->driver_data = NULL;
609 result = -ENODEV;
610 goto remove_dmar;
611 }
612
613 if (no_aspm)
614 pcie_no_aspm();
615
616 pci_acpi_add_bus_pm_notifier(device);
617 device_set_wakeup_capable(root->bus->bridge, device->wakeup.flags.valid);
618
619 if (hotadd) {
620 pcibios_resource_survey_bus(root->bus);
621 pci_assign_unassigned_root_bus_resources(root->bus);
622 /*
623 * This is only called for the hotadd case. For the boot-time
624 * case, we need to wait until after PCI initialization in
625 * order to deal with IOAPICs mapped in on a PCI BAR.
626 *
627 * This is currently x86-specific, because acpi_ioapic_add()
628 * is an empty function without CONFIG_ACPI_HOTPLUG_IOAPIC.
629 * And CONFIG_ACPI_HOTPLUG_IOAPIC depends on CONFIG_X86_IO_APIC
630 * (see drivers/acpi/Kconfig).
631 */
632 acpi_ioapic_add(root->device->handle);
633 }
634
635 pci_lock_rescan_remove();
636 pci_bus_add_devices(root->bus);
637 pci_unlock_rescan_remove();
638 return 1;
639
640remove_dmar:
641 if (hotadd)
642 dmar_device_remove(handle);
643end:
644 kfree(root);
645 return result;
646}
647
648static void acpi_pci_root_remove(struct acpi_device *device)
649{
650 struct acpi_pci_root *root = acpi_driver_data(device);
651
652 pci_lock_rescan_remove();
653
654 pci_stop_root_bus(root->bus);
655
656 pci_ioapic_remove(root);
657 device_set_wakeup_capable(root->bus->bridge, false);
658 pci_acpi_remove_bus_pm_notifier(device);
659
660 pci_remove_root_bus(root->bus);
661 WARN_ON(acpi_ioapic_remove(root));
662
663 dmar_device_remove(device->handle);
664
665 pci_unlock_rescan_remove();
666
667 kfree(root);
668}
669
670/*
671 * Following code to support acpi_pci_root_create() is copied from
672 * arch/x86/pci/acpi.c and modified so it could be reused by x86, IA64
673 * and ARM64.
674 */
675static void acpi_pci_root_validate_resources(struct device *dev,
676 struct list_head *resources,
677 unsigned long type)
678{
679 LIST_HEAD(list);
680 struct resource *res1, *res2, *root = NULL;
681 struct resource_entry *tmp, *entry, *entry2;
682
683 BUG_ON((type & (IORESOURCE_MEM | IORESOURCE_IO)) == 0);
684 root = (type & IORESOURCE_MEM) ? &iomem_resource : &ioport_resource;
685
686 list_splice_init(resources, &list);
687 resource_list_for_each_entry_safe(entry, tmp, &list) {
688 bool free = false;
689 resource_size_t end;
690
691 res1 = entry->res;
692 if (!(res1->flags & type))
693 goto next;
694
695 /* Exclude non-addressable range or non-addressable portion */
696 end = min(res1->end, root->end);
697 if (end <= res1->start) {
698 dev_info(dev, "host bridge window %pR (ignored, not CPU addressable)\n",
699 res1);
700 free = true;
701 goto next;
702 } else if (res1->end != end) {
703 dev_info(dev, "host bridge window %pR ([%#llx-%#llx] ignored, not CPU addressable)\n",
704 res1, (unsigned long long)end + 1,
705 (unsigned long long)res1->end);
706 res1->end = end;
707 }
708
709 resource_list_for_each_entry(entry2, resources) {
710 res2 = entry2->res;
711 if (!(res2->flags & type))
712 continue;
713
714 /*
715 * I don't like throwing away windows because then
716 * our resources no longer match the ACPI _CRS, but
717 * the kernel resource tree doesn't allow overlaps.
718 */
719 if (resource_overlaps(res1, res2)) {
720 res2->start = min(res1->start, res2->start);
721 res2->end = max(res1->end, res2->end);
722 dev_info(dev, "host bridge window expanded to %pR; %pR ignored\n",
723 res2, res1);
724 free = true;
725 goto next;
726 }
727 }
728
729next:
730 resource_list_del(entry);
731 if (free)
732 resource_list_free_entry(entry);
733 else
734 resource_list_add_tail(entry, resources);
735 }
736}
737
738static void acpi_pci_root_remap_iospace(struct fwnode_handle *fwnode,
739 struct resource_entry *entry)
740{
741#ifdef PCI_IOBASE
742 struct resource *res = entry->res;
743 resource_size_t cpu_addr = res->start;
744 resource_size_t pci_addr = cpu_addr - entry->offset;
745 resource_size_t length = resource_size(res);
746 unsigned long port;
747
748 if (pci_register_io_range(fwnode, cpu_addr, length))
749 goto err;
750
751 port = pci_address_to_pio(cpu_addr);
752 if (port == (unsigned long)-1)
753 goto err;
754
755 res->start = port;
756 res->end = port + length - 1;
757 entry->offset = port - pci_addr;
758
759 if (pci_remap_iospace(res, cpu_addr) < 0)
760 goto err;
761
762 pr_info("Remapped I/O %pa to %pR\n", &cpu_addr, res);
763 return;
764err:
765 res->flags |= IORESOURCE_DISABLED;
766#endif
767}
768
769int acpi_pci_probe_root_resources(struct acpi_pci_root_info *info)
770{
771 int ret;
772 struct list_head *list = &info->resources;
773 struct acpi_device *device = info->bridge;
774 struct resource_entry *entry, *tmp;
775 unsigned long flags;
776
777 flags = IORESOURCE_IO | IORESOURCE_MEM | IORESOURCE_MEM_8AND16BIT;
778 ret = acpi_dev_get_resources(device, list,
779 acpi_dev_filter_resource_type_cb,
780 (void *)flags);
781 if (ret < 0)
782 dev_warn(&device->dev,
783 "failed to parse _CRS method, error code %d\n", ret);
784 else if (ret == 0)
785 dev_dbg(&device->dev,
786 "no IO and memory resources present in _CRS\n");
787 else {
788 resource_list_for_each_entry_safe(entry, tmp, list) {
789 if (entry->res->flags & IORESOURCE_IO)
790 acpi_pci_root_remap_iospace(&device->fwnode,
791 entry);
792
793 if (entry->res->flags & IORESOURCE_DISABLED)
794 resource_list_destroy_entry(entry);
795 else
796 entry->res->name = info->name;
797 }
798 acpi_pci_root_validate_resources(&device->dev, list,
799 IORESOURCE_MEM);
800 acpi_pci_root_validate_resources(&device->dev, list,
801 IORESOURCE_IO);
802 }
803
804 return ret;
805}
806
807static void pci_acpi_root_add_resources(struct acpi_pci_root_info *info)
808{
809 struct resource_entry *entry, *tmp;
810 struct resource *res, *conflict, *root = NULL;
811
812 resource_list_for_each_entry_safe(entry, tmp, &info->resources) {
813 res = entry->res;
814 if (res->flags & IORESOURCE_MEM)
815 root = &iomem_resource;
816 else if (res->flags & IORESOURCE_IO)
817 root = &ioport_resource;
818 else
819 continue;
820
821 /*
822 * Some legacy x86 host bridge drivers use iomem_resource and
823 * ioport_resource as default resource pool, skip it.
824 */
825 if (res == root)
826 continue;
827
828 conflict = insert_resource_conflict(root, res);
829 if (conflict) {
830 dev_info(&info->bridge->dev,
831 "ignoring host bridge window %pR (conflicts with %s %pR)\n",
832 res, conflict->name, conflict);
833 resource_list_destroy_entry(entry);
834 }
835 }
836}
837
838static void __acpi_pci_root_release_info(struct acpi_pci_root_info *info)
839{
840 struct resource *res;
841 struct resource_entry *entry, *tmp;
842
843 if (!info)
844 return;
845
846 resource_list_for_each_entry_safe(entry, tmp, &info->resources) {
847 res = entry->res;
848 if (res->parent &&
849 (res->flags & (IORESOURCE_MEM | IORESOURCE_IO)))
850 release_resource(res);
851 resource_list_destroy_entry(entry);
852 }
853
854 info->ops->release_info(info);
855}
856
857static void acpi_pci_root_release_info(struct pci_host_bridge *bridge)
858{
859 struct resource *res;
860 struct resource_entry *entry;
861
862 resource_list_for_each_entry(entry, &bridge->windows) {
863 res = entry->res;
864 if (res->flags & IORESOURCE_IO)
865 pci_unmap_iospace(res);
866 if (res->parent &&
867 (res->flags & (IORESOURCE_MEM | IORESOURCE_IO)))
868 release_resource(res);
869 }
870 __acpi_pci_root_release_info(bridge->release_data);
871}
872
873struct pci_bus *acpi_pci_root_create(struct acpi_pci_root *root,
874 struct acpi_pci_root_ops *ops,
875 struct acpi_pci_root_info *info,
876 void *sysdata)
877{
878 int ret, busnum = root->secondary.start;
879 struct acpi_device *device = root->device;
880 int node = acpi_get_node(device->handle);
881 struct pci_bus *bus;
882 struct pci_host_bridge *host_bridge;
883 union acpi_object *obj;
884
885 info->root = root;
886 info->bridge = device;
887 info->ops = ops;
888 INIT_LIST_HEAD(&info->resources);
889 snprintf(info->name, sizeof(info->name), "PCI Bus %04x:%02x",
890 root->segment, busnum);
891
892 if (ops->init_info && ops->init_info(info))
893 goto out_release_info;
894 if (ops->prepare_resources)
895 ret = ops->prepare_resources(info);
896 else
897 ret = acpi_pci_probe_root_resources(info);
898 if (ret < 0)
899 goto out_release_info;
900
901 pci_acpi_root_add_resources(info);
902 pci_add_resource(&info->resources, &root->secondary);
903 bus = pci_create_root_bus(NULL, busnum, ops->pci_ops,
904 sysdata, &info->resources);
905 if (!bus)
906 goto out_release_info;
907
908 host_bridge = to_pci_host_bridge(bus->bridge);
909 if (!(root->osc_control_set & OSC_PCI_EXPRESS_NATIVE_HP_CONTROL))
910 host_bridge->native_pcie_hotplug = 0;
911 if (!(root->osc_control_set & OSC_PCI_SHPC_NATIVE_HP_CONTROL))
912 host_bridge->native_shpc_hotplug = 0;
913 if (!(root->osc_control_set & OSC_PCI_EXPRESS_AER_CONTROL))
914 host_bridge->native_aer = 0;
915 if (!(root->osc_control_set & OSC_PCI_EXPRESS_PME_CONTROL))
916 host_bridge->native_pme = 0;
917 if (!(root->osc_control_set & OSC_PCI_EXPRESS_LTR_CONTROL))
918 host_bridge->native_ltr = 0;
919
920 /*
921 * Evaluate the "PCI Boot Configuration" _DSM Function. If it
922 * exists and returns 0, we must preserve any PCI resource
923 * assignments made by firmware for this host bridge.
924 */
925 obj = acpi_evaluate_dsm(ACPI_HANDLE(bus->bridge), &pci_acpi_dsm_guid, 1,
926 IGNORE_PCI_BOOT_CONFIG_DSM, NULL);
927 if (obj && obj->type == ACPI_TYPE_INTEGER && obj->integer.value == 0)
928 host_bridge->preserve_config = 1;
929 ACPI_FREE(obj);
930
931 pci_scan_child_bus(bus);
932 pci_set_host_bridge_release(host_bridge, acpi_pci_root_release_info,
933 info);
934 if (node != NUMA_NO_NODE)
935 dev_printk(KERN_DEBUG, &bus->dev, "on NUMA node %d\n", node);
936 return bus;
937
938out_release_info:
939 __acpi_pci_root_release_info(info);
940 return NULL;
941}
942
943void __init acpi_pci_root_init(void)
944{
945 acpi_hest_init();
946 if (acpi_pci_disabled)
947 return;
948
949 pci_acpi_crs_quirks();
950 acpi_scan_add_handler_with_hotplug(&pci_root_handler, "pci_root");
951}
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * pci_root.c - ACPI PCI Root Bridge Driver ($Revision: 40 $)
4 *
5 * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
6 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
7 */
8
9#define pr_fmt(fmt) "ACPI: " fmt
10
11#include <linux/kernel.h>
12#include <linux/module.h>
13#include <linux/init.h>
14#include <linux/types.h>
15#include <linux/mutex.h>
16#include <linux/pm.h>
17#include <linux/pm_runtime.h>
18#include <linux/pci.h>
19#include <linux/pci-acpi.h>
20#include <linux/dmar.h>
21#include <linux/acpi.h>
22#include <linux/slab.h>
23#include <linux/dmi.h>
24#include <linux/platform_data/x86/apple.h>
25#include <acpi/apei.h> /* for acpi_hest_init() */
26
27#include "internal.h"
28
29#define ACPI_PCI_ROOT_CLASS "pci_bridge"
30#define ACPI_PCI_ROOT_DEVICE_NAME "PCI Root Bridge"
31static int acpi_pci_root_add(struct acpi_device *device,
32 const struct acpi_device_id *not_used);
33static void acpi_pci_root_remove(struct acpi_device *device);
34
35static int acpi_pci_root_scan_dependent(struct acpi_device *adev)
36{
37 acpiphp_check_host_bridge(adev);
38 return 0;
39}
40
41#define ACPI_PCIE_REQ_SUPPORT (OSC_PCI_EXT_CONFIG_SUPPORT \
42 | OSC_PCI_ASPM_SUPPORT \
43 | OSC_PCI_CLOCK_PM_SUPPORT \
44 | OSC_PCI_MSI_SUPPORT)
45
46static const struct acpi_device_id root_device_ids[] = {
47 {"PNP0A03", 0},
48 {"", 0},
49};
50
51static struct acpi_scan_handler pci_root_handler = {
52 .ids = root_device_ids,
53 .attach = acpi_pci_root_add,
54 .detach = acpi_pci_root_remove,
55 .hotplug = {
56 .enabled = true,
57 .scan_dependent = acpi_pci_root_scan_dependent,
58 },
59};
60
61/**
62 * acpi_is_root_bridge - determine whether an ACPI CA node is a PCI root bridge
63 * @handle: the ACPI CA node in question.
64 *
65 * Note: we could make this API take a struct acpi_device * instead, but
66 * for now, it's more convenient to operate on an acpi_handle.
67 */
68int acpi_is_root_bridge(acpi_handle handle)
69{
70 int ret;
71 struct acpi_device *device;
72
73 ret = acpi_bus_get_device(handle, &device);
74 if (ret)
75 return 0;
76
77 ret = acpi_match_device_ids(device, root_device_ids);
78 if (ret)
79 return 0;
80 else
81 return 1;
82}
83EXPORT_SYMBOL_GPL(acpi_is_root_bridge);
84
85static acpi_status
86get_root_bridge_busnr_callback(struct acpi_resource *resource, void *data)
87{
88 struct resource *res = data;
89 struct acpi_resource_address64 address;
90 acpi_status status;
91
92 status = acpi_resource_to_address64(resource, &address);
93 if (ACPI_FAILURE(status))
94 return AE_OK;
95
96 if ((address.address.address_length > 0) &&
97 (address.resource_type == ACPI_BUS_NUMBER_RANGE)) {
98 res->start = address.address.minimum;
99 res->end = address.address.minimum + address.address.address_length - 1;
100 }
101
102 return AE_OK;
103}
104
105static acpi_status try_get_root_bridge_busnr(acpi_handle handle,
106 struct resource *res)
107{
108 acpi_status status;
109
110 res->start = -1;
111 status =
112 acpi_walk_resources(handle, METHOD_NAME__CRS,
113 get_root_bridge_busnr_callback, res);
114 if (ACPI_FAILURE(status))
115 return status;
116 if (res->start == -1)
117 return AE_ERROR;
118 return AE_OK;
119}
120
121struct pci_osc_bit_struct {
122 u32 bit;
123 char *desc;
124};
125
126static struct pci_osc_bit_struct pci_osc_support_bit[] = {
127 { OSC_PCI_EXT_CONFIG_SUPPORT, "ExtendedConfig" },
128 { OSC_PCI_ASPM_SUPPORT, "ASPM" },
129 { OSC_PCI_CLOCK_PM_SUPPORT, "ClockPM" },
130 { OSC_PCI_SEGMENT_GROUPS_SUPPORT, "Segments" },
131 { OSC_PCI_MSI_SUPPORT, "MSI" },
132 { OSC_PCI_EDR_SUPPORT, "EDR" },
133 { OSC_PCI_HPX_TYPE_3_SUPPORT, "HPX-Type3" },
134};
135
136static struct pci_osc_bit_struct pci_osc_control_bit[] = {
137 { OSC_PCI_EXPRESS_NATIVE_HP_CONTROL, "PCIeHotplug" },
138 { OSC_PCI_SHPC_NATIVE_HP_CONTROL, "SHPCHotplug" },
139 { OSC_PCI_EXPRESS_PME_CONTROL, "PME" },
140 { OSC_PCI_EXPRESS_AER_CONTROL, "AER" },
141 { OSC_PCI_EXPRESS_CAPABILITY_CONTROL, "PCIeCapability" },
142 { OSC_PCI_EXPRESS_LTR_CONTROL, "LTR" },
143 { OSC_PCI_EXPRESS_DPC_CONTROL, "DPC" },
144};
145
146static void decode_osc_bits(struct acpi_pci_root *root, char *msg, u32 word,
147 struct pci_osc_bit_struct *table, int size)
148{
149 char buf[80];
150 int i, len = 0;
151 struct pci_osc_bit_struct *entry;
152
153 buf[0] = '\0';
154 for (i = 0, entry = table; i < size; i++, entry++)
155 if (word & entry->bit)
156 len += scnprintf(buf + len, sizeof(buf) - len, "%s%s",
157 len ? " " : "", entry->desc);
158
159 dev_info(&root->device->dev, "_OSC: %s [%s]\n", msg, buf);
160}
161
162static void decode_osc_support(struct acpi_pci_root *root, char *msg, u32 word)
163{
164 decode_osc_bits(root, msg, word, pci_osc_support_bit,
165 ARRAY_SIZE(pci_osc_support_bit));
166}
167
168static void decode_osc_control(struct acpi_pci_root *root, char *msg, u32 word)
169{
170 decode_osc_bits(root, msg, word, pci_osc_control_bit,
171 ARRAY_SIZE(pci_osc_control_bit));
172}
173
174static u8 pci_osc_uuid_str[] = "33DB4D5B-1FF7-401C-9657-7441C03DD766";
175
176static acpi_status acpi_pci_run_osc(acpi_handle handle,
177 const u32 *capbuf, u32 *retval)
178{
179 struct acpi_osc_context context = {
180 .uuid_str = pci_osc_uuid_str,
181 .rev = 1,
182 .cap.length = 12,
183 .cap.pointer = (void *)capbuf,
184 };
185 acpi_status status;
186
187 status = acpi_run_osc(handle, &context);
188 if (ACPI_SUCCESS(status)) {
189 *retval = *((u32 *)(context.ret.pointer + 8));
190 kfree(context.ret.pointer);
191 }
192 return status;
193}
194
195static acpi_status acpi_pci_query_osc(struct acpi_pci_root *root,
196 u32 support,
197 u32 *control)
198{
199 acpi_status status;
200 u32 result, capbuf[3];
201
202 support &= OSC_PCI_SUPPORT_MASKS;
203 support |= root->osc_support_set;
204
205 capbuf[OSC_QUERY_DWORD] = OSC_QUERY_ENABLE;
206 capbuf[OSC_SUPPORT_DWORD] = support;
207 if (control) {
208 *control &= OSC_PCI_CONTROL_MASKS;
209 capbuf[OSC_CONTROL_DWORD] = *control | root->osc_control_set;
210 } else {
211 /* Run _OSC query only with existing controls. */
212 capbuf[OSC_CONTROL_DWORD] = root->osc_control_set;
213 }
214
215 status = acpi_pci_run_osc(root->device->handle, capbuf, &result);
216 if (ACPI_SUCCESS(status)) {
217 root->osc_support_set = support;
218 if (control)
219 *control = result;
220 }
221 return status;
222}
223
224static acpi_status acpi_pci_osc_support(struct acpi_pci_root *root, u32 flags)
225{
226 return acpi_pci_query_osc(root, flags, NULL);
227}
228
229struct acpi_pci_root *acpi_pci_find_root(acpi_handle handle)
230{
231 struct acpi_pci_root *root;
232 struct acpi_device *device;
233
234 if (acpi_bus_get_device(handle, &device) ||
235 acpi_match_device_ids(device, root_device_ids))
236 return NULL;
237
238 root = acpi_driver_data(device);
239
240 return root;
241}
242EXPORT_SYMBOL_GPL(acpi_pci_find_root);
243
244struct acpi_handle_node {
245 struct list_head node;
246 acpi_handle handle;
247};
248
249/**
250 * acpi_get_pci_dev - convert ACPI CA handle to struct pci_dev
251 * @handle: the handle in question
252 *
253 * Given an ACPI CA handle, the desired PCI device is located in the
254 * list of PCI devices.
255 *
256 * If the device is found, its reference count is increased and this
257 * function returns a pointer to its data structure. The caller must
258 * decrement the reference count by calling pci_dev_put().
259 * If no device is found, %NULL is returned.
260 */
261struct pci_dev *acpi_get_pci_dev(acpi_handle handle)
262{
263 int dev, fn;
264 unsigned long long adr;
265 acpi_status status;
266 acpi_handle phandle;
267 struct pci_bus *pbus;
268 struct pci_dev *pdev = NULL;
269 struct acpi_handle_node *node, *tmp;
270 struct acpi_pci_root *root;
271 LIST_HEAD(device_list);
272
273 /*
274 * Walk up the ACPI CA namespace until we reach a PCI root bridge.
275 */
276 phandle = handle;
277 while (!acpi_is_root_bridge(phandle)) {
278 node = kzalloc(sizeof(struct acpi_handle_node), GFP_KERNEL);
279 if (!node)
280 goto out;
281
282 INIT_LIST_HEAD(&node->node);
283 node->handle = phandle;
284 list_add(&node->node, &device_list);
285
286 status = acpi_get_parent(phandle, &phandle);
287 if (ACPI_FAILURE(status))
288 goto out;
289 }
290
291 root = acpi_pci_find_root(phandle);
292 if (!root)
293 goto out;
294
295 pbus = root->bus;
296
297 /*
298 * Now, walk back down the PCI device tree until we return to our
299 * original handle. Assumes that everything between the PCI root
300 * bridge and the device we're looking for must be a P2P bridge.
301 */
302 list_for_each_entry(node, &device_list, node) {
303 acpi_handle hnd = node->handle;
304 status = acpi_evaluate_integer(hnd, "_ADR", NULL, &adr);
305 if (ACPI_FAILURE(status))
306 goto out;
307 dev = (adr >> 16) & 0xffff;
308 fn = adr & 0xffff;
309
310 pdev = pci_get_slot(pbus, PCI_DEVFN(dev, fn));
311 if (!pdev || hnd == handle)
312 break;
313
314 pbus = pdev->subordinate;
315 pci_dev_put(pdev);
316
317 /*
318 * This function may be called for a non-PCI device that has a
319 * PCI parent (eg. a disk under a PCI SATA controller). In that
320 * case pdev->subordinate will be NULL for the parent.
321 */
322 if (!pbus) {
323 dev_dbg(&pdev->dev, "Not a PCI-to-PCI bridge\n");
324 pdev = NULL;
325 break;
326 }
327 }
328out:
329 list_for_each_entry_safe(node, tmp, &device_list, node)
330 kfree(node);
331
332 return pdev;
333}
334EXPORT_SYMBOL_GPL(acpi_get_pci_dev);
335
336/**
337 * acpi_pci_osc_control_set - Request control of PCI root _OSC features.
338 * @handle: ACPI handle of a PCI root bridge (or PCIe Root Complex).
339 * @mask: Mask of _OSC bits to request control of, place to store control mask.
340 * @req: Mask of _OSC bits the control of is essential to the caller.
341 *
342 * Run _OSC query for @mask and if that is successful, compare the returned
343 * mask of control bits with @req. If all of the @req bits are set in the
344 * returned mask, run _OSC request for it.
345 *
346 * The variable at the @mask address may be modified regardless of whether or
347 * not the function returns success. On success it will contain the mask of
348 * _OSC bits the BIOS has granted control of, but its contents are meaningless
349 * on failure.
350 **/
351static acpi_status acpi_pci_osc_control_set(acpi_handle handle, u32 *mask, u32 req)
352{
353 struct acpi_pci_root *root;
354 acpi_status status;
355 u32 ctrl, capbuf[3];
356
357 if (!mask)
358 return AE_BAD_PARAMETER;
359
360 ctrl = *mask & OSC_PCI_CONTROL_MASKS;
361 if ((ctrl & req) != req)
362 return AE_TYPE;
363
364 root = acpi_pci_find_root(handle);
365 if (!root)
366 return AE_NOT_EXIST;
367
368 *mask = ctrl | root->osc_control_set;
369 /* No need to evaluate _OSC if the control was already granted. */
370 if ((root->osc_control_set & ctrl) == ctrl)
371 return AE_OK;
372
373 /* Need to check the available controls bits before requesting them. */
374 while (*mask) {
375 status = acpi_pci_query_osc(root, root->osc_support_set, mask);
376 if (ACPI_FAILURE(status))
377 return status;
378 if (ctrl == *mask)
379 break;
380 decode_osc_control(root, "platform does not support",
381 ctrl & ~(*mask));
382 ctrl = *mask;
383 }
384
385 if ((ctrl & req) != req) {
386 decode_osc_control(root, "not requesting control; platform does not support",
387 req & ~(ctrl));
388 return AE_SUPPORT;
389 }
390
391 capbuf[OSC_QUERY_DWORD] = 0;
392 capbuf[OSC_SUPPORT_DWORD] = root->osc_support_set;
393 capbuf[OSC_CONTROL_DWORD] = ctrl;
394 status = acpi_pci_run_osc(handle, capbuf, mask);
395 if (ACPI_FAILURE(status))
396 return status;
397
398 root->osc_control_set = *mask;
399 return AE_OK;
400}
401
402static void negotiate_os_control(struct acpi_pci_root *root, int *no_aspm,
403 bool is_pcie)
404{
405 u32 support, control, requested;
406 acpi_status status;
407 struct acpi_device *device = root->device;
408 acpi_handle handle = device->handle;
409
410 /*
411 * Apple always return failure on _OSC calls when _OSI("Darwin") has
412 * been called successfully. We know the feature set supported by the
413 * platform, so avoid calling _OSC at all
414 */
415 if (x86_apple_machine) {
416 root->osc_control_set = ~OSC_PCI_EXPRESS_PME_CONTROL;
417 decode_osc_control(root, "OS assumes control of",
418 root->osc_control_set);
419 return;
420 }
421
422 /*
423 * All supported architectures that use ACPI have support for
424 * PCI domains, so we indicate this in _OSC support capabilities.
425 */
426 support = OSC_PCI_SEGMENT_GROUPS_SUPPORT;
427 support |= OSC_PCI_HPX_TYPE_3_SUPPORT;
428 if (pci_ext_cfg_avail())
429 support |= OSC_PCI_EXT_CONFIG_SUPPORT;
430 if (pcie_aspm_support_enabled())
431 support |= OSC_PCI_ASPM_SUPPORT | OSC_PCI_CLOCK_PM_SUPPORT;
432 if (pci_msi_enabled())
433 support |= OSC_PCI_MSI_SUPPORT;
434 if (IS_ENABLED(CONFIG_PCIE_EDR))
435 support |= OSC_PCI_EDR_SUPPORT;
436
437 decode_osc_support(root, "OS supports", support);
438 status = acpi_pci_osc_support(root, support);
439 if (ACPI_FAILURE(status)) {
440 *no_aspm = 1;
441
442 /* _OSC is optional for PCI host bridges */
443 if ((status == AE_NOT_FOUND) && !is_pcie)
444 return;
445
446 dev_info(&device->dev, "_OSC: platform retains control of PCIe features (%s)\n",
447 acpi_format_exception(status));
448 return;
449 }
450
451 if (pcie_ports_disabled) {
452 dev_info(&device->dev, "PCIe port services disabled; not requesting _OSC control\n");
453 return;
454 }
455
456 if ((support & ACPI_PCIE_REQ_SUPPORT) != ACPI_PCIE_REQ_SUPPORT) {
457 decode_osc_support(root, "not requesting OS control; OS requires",
458 ACPI_PCIE_REQ_SUPPORT);
459 return;
460 }
461
462 control = OSC_PCI_EXPRESS_CAPABILITY_CONTROL
463 | OSC_PCI_EXPRESS_PME_CONTROL;
464
465 if (IS_ENABLED(CONFIG_PCIEASPM))
466 control |= OSC_PCI_EXPRESS_LTR_CONTROL;
467
468 if (IS_ENABLED(CONFIG_HOTPLUG_PCI_PCIE))
469 control |= OSC_PCI_EXPRESS_NATIVE_HP_CONTROL;
470
471 if (IS_ENABLED(CONFIG_HOTPLUG_PCI_SHPC))
472 control |= OSC_PCI_SHPC_NATIVE_HP_CONTROL;
473
474 if (pci_aer_available())
475 control |= OSC_PCI_EXPRESS_AER_CONTROL;
476
477 /*
478 * Per the Downstream Port Containment Related Enhancements ECN to
479 * the PCI Firmware Spec, r3.2, sec 4.5.1, table 4-5,
480 * OSC_PCI_EXPRESS_DPC_CONTROL indicates the OS supports both DPC
481 * and EDR.
482 */
483 if (IS_ENABLED(CONFIG_PCIE_DPC) && IS_ENABLED(CONFIG_PCIE_EDR))
484 control |= OSC_PCI_EXPRESS_DPC_CONTROL;
485
486 requested = control;
487 status = acpi_pci_osc_control_set(handle, &control,
488 OSC_PCI_EXPRESS_CAPABILITY_CONTROL);
489 if (ACPI_SUCCESS(status)) {
490 decode_osc_control(root, "OS now controls", control);
491 if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_ASPM) {
492 /*
493 * We have ASPM control, but the FADT indicates that
494 * it's unsupported. Leave existing configuration
495 * intact and prevent the OS from touching it.
496 */
497 dev_info(&device->dev, "FADT indicates ASPM is unsupported, using BIOS configuration\n");
498 *no_aspm = 1;
499 }
500 } else {
501 decode_osc_control(root, "OS requested", requested);
502 decode_osc_control(root, "platform willing to grant", control);
503 dev_info(&device->dev, "_OSC: platform retains control of PCIe features (%s)\n",
504 acpi_format_exception(status));
505
506 /*
507 * We want to disable ASPM here, but aspm_disabled
508 * needs to remain in its state from boot so that we
509 * properly handle PCIe 1.1 devices. So we set this
510 * flag here, to defer the action until after the ACPI
511 * root scan.
512 */
513 *no_aspm = 1;
514 }
515}
516
517static int acpi_pci_root_add(struct acpi_device *device,
518 const struct acpi_device_id *not_used)
519{
520 unsigned long long segment, bus;
521 acpi_status status;
522 int result;
523 struct acpi_pci_root *root;
524 acpi_handle handle = device->handle;
525 int no_aspm = 0;
526 bool hotadd = system_state == SYSTEM_RUNNING;
527 bool is_pcie;
528
529 root = kzalloc(sizeof(struct acpi_pci_root), GFP_KERNEL);
530 if (!root)
531 return -ENOMEM;
532
533 segment = 0;
534 status = acpi_evaluate_integer(handle, METHOD_NAME__SEG, NULL,
535 &segment);
536 if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
537 dev_err(&device->dev, "can't evaluate _SEG\n");
538 result = -ENODEV;
539 goto end;
540 }
541
542 /* Check _CRS first, then _BBN. If no _BBN, default to zero. */
543 root->secondary.flags = IORESOURCE_BUS;
544 status = try_get_root_bridge_busnr(handle, &root->secondary);
545 if (ACPI_FAILURE(status)) {
546 /*
547 * We need both the start and end of the downstream bus range
548 * to interpret _CBA (MMCONFIG base address), so it really is
549 * supposed to be in _CRS. If we don't find it there, all we
550 * can do is assume [_BBN-0xFF] or [0-0xFF].
551 */
552 root->secondary.end = 0xFF;
553 dev_warn(&device->dev,
554 FW_BUG "no secondary bus range in _CRS\n");
555 status = acpi_evaluate_integer(handle, METHOD_NAME__BBN,
556 NULL, &bus);
557 if (ACPI_SUCCESS(status))
558 root->secondary.start = bus;
559 else if (status == AE_NOT_FOUND)
560 root->secondary.start = 0;
561 else {
562 dev_err(&device->dev, "can't evaluate _BBN\n");
563 result = -ENODEV;
564 goto end;
565 }
566 }
567
568 root->device = device;
569 root->segment = segment & 0xFFFF;
570 strcpy(acpi_device_name(device), ACPI_PCI_ROOT_DEVICE_NAME);
571 strcpy(acpi_device_class(device), ACPI_PCI_ROOT_CLASS);
572 device->driver_data = root;
573
574 if (hotadd && dmar_device_add(handle)) {
575 result = -ENXIO;
576 goto end;
577 }
578
579 pr_info("%s [%s] (domain %04x %pR)\n",
580 acpi_device_name(device), acpi_device_bid(device),
581 root->segment, &root->secondary);
582
583 root->mcfg_addr = acpi_pci_root_get_mcfg_addr(handle);
584
585 is_pcie = strcmp(acpi_device_hid(device), "PNP0A08") == 0;
586 negotiate_os_control(root, &no_aspm, is_pcie);
587
588 /*
589 * TBD: Need PCI interface for enumeration/configuration of roots.
590 */
591
592 /*
593 * Scan the Root Bridge
594 * --------------------
595 * Must do this prior to any attempt to bind the root device, as the
596 * PCI namespace does not get created until this call is made (and
597 * thus the root bridge's pci_dev does not exist).
598 */
599 root->bus = pci_acpi_scan_root(root);
600 if (!root->bus) {
601 dev_err(&device->dev,
602 "Bus %04x:%02x not present in PCI namespace\n",
603 root->segment, (unsigned int)root->secondary.start);
604 device->driver_data = NULL;
605 result = -ENODEV;
606 goto remove_dmar;
607 }
608
609 if (no_aspm)
610 pcie_no_aspm();
611
612 pci_acpi_add_bus_pm_notifier(device);
613 device_set_wakeup_capable(root->bus->bridge, device->wakeup.flags.valid);
614
615 if (hotadd) {
616 pcibios_resource_survey_bus(root->bus);
617 pci_assign_unassigned_root_bus_resources(root->bus);
618 /*
619 * This is only called for the hotadd case. For the boot-time
620 * case, we need to wait until after PCI initialization in
621 * order to deal with IOAPICs mapped in on a PCI BAR.
622 *
623 * This is currently x86-specific, because acpi_ioapic_add()
624 * is an empty function without CONFIG_ACPI_HOTPLUG_IOAPIC.
625 * And CONFIG_ACPI_HOTPLUG_IOAPIC depends on CONFIG_X86_IO_APIC
626 * (see drivers/acpi/Kconfig).
627 */
628 acpi_ioapic_add(root->device->handle);
629 }
630
631 pci_lock_rescan_remove();
632 pci_bus_add_devices(root->bus);
633 pci_unlock_rescan_remove();
634 return 1;
635
636remove_dmar:
637 if (hotadd)
638 dmar_device_remove(handle);
639end:
640 kfree(root);
641 return result;
642}
643
644static void acpi_pci_root_remove(struct acpi_device *device)
645{
646 struct acpi_pci_root *root = acpi_driver_data(device);
647
648 pci_lock_rescan_remove();
649
650 pci_stop_root_bus(root->bus);
651
652 pci_ioapic_remove(root);
653 device_set_wakeup_capable(root->bus->bridge, false);
654 pci_acpi_remove_bus_pm_notifier(device);
655
656 pci_remove_root_bus(root->bus);
657 WARN_ON(acpi_ioapic_remove(root));
658
659 dmar_device_remove(device->handle);
660
661 pci_unlock_rescan_remove();
662
663 kfree(root);
664}
665
666/*
667 * Following code to support acpi_pci_root_create() is copied from
668 * arch/x86/pci/acpi.c and modified so it could be reused by x86, IA64
669 * and ARM64.
670 */
671static void acpi_pci_root_validate_resources(struct device *dev,
672 struct list_head *resources,
673 unsigned long type)
674{
675 LIST_HEAD(list);
676 struct resource *res1, *res2, *root = NULL;
677 struct resource_entry *tmp, *entry, *entry2;
678
679 BUG_ON((type & (IORESOURCE_MEM | IORESOURCE_IO)) == 0);
680 root = (type & IORESOURCE_MEM) ? &iomem_resource : &ioport_resource;
681
682 list_splice_init(resources, &list);
683 resource_list_for_each_entry_safe(entry, tmp, &list) {
684 bool free = false;
685 resource_size_t end;
686
687 res1 = entry->res;
688 if (!(res1->flags & type))
689 goto next;
690
691 /* Exclude non-addressable range or non-addressable portion */
692 end = min(res1->end, root->end);
693 if (end <= res1->start) {
694 dev_info(dev, "host bridge window %pR (ignored, not CPU addressable)\n",
695 res1);
696 free = true;
697 goto next;
698 } else if (res1->end != end) {
699 dev_info(dev, "host bridge window %pR ([%#llx-%#llx] ignored, not CPU addressable)\n",
700 res1, (unsigned long long)end + 1,
701 (unsigned long long)res1->end);
702 res1->end = end;
703 }
704
705 resource_list_for_each_entry(entry2, resources) {
706 res2 = entry2->res;
707 if (!(res2->flags & type))
708 continue;
709
710 /*
711 * I don't like throwing away windows because then
712 * our resources no longer match the ACPI _CRS, but
713 * the kernel resource tree doesn't allow overlaps.
714 */
715 if (resource_union(res1, res2, res2)) {
716 dev_info(dev, "host bridge window expanded to %pR; %pR ignored\n",
717 res2, res1);
718 free = true;
719 goto next;
720 }
721 }
722
723next:
724 resource_list_del(entry);
725 if (free)
726 resource_list_free_entry(entry);
727 else
728 resource_list_add_tail(entry, resources);
729 }
730}
731
732static void acpi_pci_root_remap_iospace(struct fwnode_handle *fwnode,
733 struct resource_entry *entry)
734{
735#ifdef PCI_IOBASE
736 struct resource *res = entry->res;
737 resource_size_t cpu_addr = res->start;
738 resource_size_t pci_addr = cpu_addr - entry->offset;
739 resource_size_t length = resource_size(res);
740 unsigned long port;
741
742 if (pci_register_io_range(fwnode, cpu_addr, length))
743 goto err;
744
745 port = pci_address_to_pio(cpu_addr);
746 if (port == (unsigned long)-1)
747 goto err;
748
749 res->start = port;
750 res->end = port + length - 1;
751 entry->offset = port - pci_addr;
752
753 if (pci_remap_iospace(res, cpu_addr) < 0)
754 goto err;
755
756 pr_info("Remapped I/O %pa to %pR\n", &cpu_addr, res);
757 return;
758err:
759 res->flags |= IORESOURCE_DISABLED;
760#endif
761}
762
763int acpi_pci_probe_root_resources(struct acpi_pci_root_info *info)
764{
765 int ret;
766 struct list_head *list = &info->resources;
767 struct acpi_device *device = info->bridge;
768 struct resource_entry *entry, *tmp;
769 unsigned long flags;
770
771 flags = IORESOURCE_IO | IORESOURCE_MEM | IORESOURCE_MEM_8AND16BIT;
772 ret = acpi_dev_get_resources(device, list,
773 acpi_dev_filter_resource_type_cb,
774 (void *)flags);
775 if (ret < 0)
776 dev_warn(&device->dev,
777 "failed to parse _CRS method, error code %d\n", ret);
778 else if (ret == 0)
779 dev_dbg(&device->dev,
780 "no IO and memory resources present in _CRS\n");
781 else {
782 resource_list_for_each_entry_safe(entry, tmp, list) {
783 if (entry->res->flags & IORESOURCE_IO)
784 acpi_pci_root_remap_iospace(&device->fwnode,
785 entry);
786
787 if (entry->res->flags & IORESOURCE_DISABLED)
788 resource_list_destroy_entry(entry);
789 else
790 entry->res->name = info->name;
791 }
792 acpi_pci_root_validate_resources(&device->dev, list,
793 IORESOURCE_MEM);
794 acpi_pci_root_validate_resources(&device->dev, list,
795 IORESOURCE_IO);
796 }
797
798 return ret;
799}
800
801static void pci_acpi_root_add_resources(struct acpi_pci_root_info *info)
802{
803 struct resource_entry *entry, *tmp;
804 struct resource *res, *conflict, *root = NULL;
805
806 resource_list_for_each_entry_safe(entry, tmp, &info->resources) {
807 res = entry->res;
808 if (res->flags & IORESOURCE_MEM)
809 root = &iomem_resource;
810 else if (res->flags & IORESOURCE_IO)
811 root = &ioport_resource;
812 else
813 continue;
814
815 /*
816 * Some legacy x86 host bridge drivers use iomem_resource and
817 * ioport_resource as default resource pool, skip it.
818 */
819 if (res == root)
820 continue;
821
822 conflict = insert_resource_conflict(root, res);
823 if (conflict) {
824 dev_info(&info->bridge->dev,
825 "ignoring host bridge window %pR (conflicts with %s %pR)\n",
826 res, conflict->name, conflict);
827 resource_list_destroy_entry(entry);
828 }
829 }
830}
831
832static void __acpi_pci_root_release_info(struct acpi_pci_root_info *info)
833{
834 struct resource *res;
835 struct resource_entry *entry, *tmp;
836
837 if (!info)
838 return;
839
840 resource_list_for_each_entry_safe(entry, tmp, &info->resources) {
841 res = entry->res;
842 if (res->parent &&
843 (res->flags & (IORESOURCE_MEM | IORESOURCE_IO)))
844 release_resource(res);
845 resource_list_destroy_entry(entry);
846 }
847
848 info->ops->release_info(info);
849}
850
851static void acpi_pci_root_release_info(struct pci_host_bridge *bridge)
852{
853 struct resource *res;
854 struct resource_entry *entry;
855
856 resource_list_for_each_entry(entry, &bridge->windows) {
857 res = entry->res;
858 if (res->flags & IORESOURCE_IO)
859 pci_unmap_iospace(res);
860 if (res->parent &&
861 (res->flags & (IORESOURCE_MEM | IORESOURCE_IO)))
862 release_resource(res);
863 }
864 __acpi_pci_root_release_info(bridge->release_data);
865}
866
867struct pci_bus *acpi_pci_root_create(struct acpi_pci_root *root,
868 struct acpi_pci_root_ops *ops,
869 struct acpi_pci_root_info *info,
870 void *sysdata)
871{
872 int ret, busnum = root->secondary.start;
873 struct acpi_device *device = root->device;
874 int node = acpi_get_node(device->handle);
875 struct pci_bus *bus;
876 struct pci_host_bridge *host_bridge;
877 union acpi_object *obj;
878
879 info->root = root;
880 info->bridge = device;
881 info->ops = ops;
882 INIT_LIST_HEAD(&info->resources);
883 snprintf(info->name, sizeof(info->name), "PCI Bus %04x:%02x",
884 root->segment, busnum);
885
886 if (ops->init_info && ops->init_info(info))
887 goto out_release_info;
888 if (ops->prepare_resources)
889 ret = ops->prepare_resources(info);
890 else
891 ret = acpi_pci_probe_root_resources(info);
892 if (ret < 0)
893 goto out_release_info;
894
895 pci_acpi_root_add_resources(info);
896 pci_add_resource(&info->resources, &root->secondary);
897 bus = pci_create_root_bus(NULL, busnum, ops->pci_ops,
898 sysdata, &info->resources);
899 if (!bus)
900 goto out_release_info;
901
902 host_bridge = to_pci_host_bridge(bus->bridge);
903 if (!(root->osc_control_set & OSC_PCI_EXPRESS_NATIVE_HP_CONTROL))
904 host_bridge->native_pcie_hotplug = 0;
905 if (!(root->osc_control_set & OSC_PCI_SHPC_NATIVE_HP_CONTROL))
906 host_bridge->native_shpc_hotplug = 0;
907 if (!(root->osc_control_set & OSC_PCI_EXPRESS_AER_CONTROL))
908 host_bridge->native_aer = 0;
909 if (!(root->osc_control_set & OSC_PCI_EXPRESS_PME_CONTROL))
910 host_bridge->native_pme = 0;
911 if (!(root->osc_control_set & OSC_PCI_EXPRESS_LTR_CONTROL))
912 host_bridge->native_ltr = 0;
913 if (!(root->osc_control_set & OSC_PCI_EXPRESS_DPC_CONTROL))
914 host_bridge->native_dpc = 0;
915
916 /*
917 * Evaluate the "PCI Boot Configuration" _DSM Function. If it
918 * exists and returns 0, we must preserve any PCI resource
919 * assignments made by firmware for this host bridge.
920 */
921 obj = acpi_evaluate_dsm(ACPI_HANDLE(bus->bridge), &pci_acpi_dsm_guid, 1,
922 DSM_PCI_PRESERVE_BOOT_CONFIG, NULL);
923 if (obj && obj->type == ACPI_TYPE_INTEGER && obj->integer.value == 0)
924 host_bridge->preserve_config = 1;
925 ACPI_FREE(obj);
926
927 pci_scan_child_bus(bus);
928 pci_set_host_bridge_release(host_bridge, acpi_pci_root_release_info,
929 info);
930 if (node != NUMA_NO_NODE)
931 dev_printk(KERN_DEBUG, &bus->dev, "on NUMA node %d\n", node);
932 return bus;
933
934out_release_info:
935 __acpi_pci_root_release_info(info);
936 return NULL;
937}
938
939void __init acpi_pci_root_init(void)
940{
941 acpi_hest_init();
942 if (acpi_pci_disabled)
943 return;
944
945 pci_acpi_crs_quirks();
946 acpi_scan_add_handler_with_hotplug(&pci_root_handler, "pci_root");
947}