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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_EDR_SUPPORT, "EDR" },
135 { OSC_PCI_HPX_TYPE_3_SUPPORT, "HPX-Type3" },
136};
137
138static struct pci_osc_bit_struct pci_osc_control_bit[] = {
139 { OSC_PCI_EXPRESS_NATIVE_HP_CONTROL, "PCIeHotplug" },
140 { OSC_PCI_SHPC_NATIVE_HP_CONTROL, "SHPCHotplug" },
141 { OSC_PCI_EXPRESS_PME_CONTROL, "PME" },
142 { OSC_PCI_EXPRESS_AER_CONTROL, "AER" },
143 { OSC_PCI_EXPRESS_CAPABILITY_CONTROL, "PCIeCapability" },
144 { OSC_PCI_EXPRESS_LTR_CONTROL, "LTR" },
145 { OSC_PCI_EXPRESS_DPC_CONTROL, "DPC" },
146};
147
148static void decode_osc_bits(struct acpi_pci_root *root, char *msg, u32 word,
149 struct pci_osc_bit_struct *table, int size)
150{
151 char buf[80];
152 int i, len = 0;
153 struct pci_osc_bit_struct *entry;
154
155 buf[0] = '\0';
156 for (i = 0, entry = table; i < size; i++, entry++)
157 if (word & entry->bit)
158 len += scnprintf(buf + len, sizeof(buf) - len, "%s%s",
159 len ? " " : "", entry->desc);
160
161 dev_info(&root->device->dev, "_OSC: %s [%s]\n", msg, buf);
162}
163
164static void decode_osc_support(struct acpi_pci_root *root, char *msg, u32 word)
165{
166 decode_osc_bits(root, msg, word, pci_osc_support_bit,
167 ARRAY_SIZE(pci_osc_support_bit));
168}
169
170static void decode_osc_control(struct acpi_pci_root *root, char *msg, u32 word)
171{
172 decode_osc_bits(root, msg, word, pci_osc_control_bit,
173 ARRAY_SIZE(pci_osc_control_bit));
174}
175
176static u8 pci_osc_uuid_str[] = "33DB4D5B-1FF7-401C-9657-7441C03DD766";
177
178static acpi_status acpi_pci_run_osc(acpi_handle handle,
179 const u32 *capbuf, u32 *retval)
180{
181 struct acpi_osc_context context = {
182 .uuid_str = pci_osc_uuid_str,
183 .rev = 1,
184 .cap.length = 12,
185 .cap.pointer = (void *)capbuf,
186 };
187 acpi_status status;
188
189 status = acpi_run_osc(handle, &context);
190 if (ACPI_SUCCESS(status)) {
191 *retval = *((u32 *)(context.ret.pointer + 8));
192 kfree(context.ret.pointer);
193 }
194 return status;
195}
196
197static acpi_status acpi_pci_query_osc(struct acpi_pci_root *root,
198 u32 support,
199 u32 *control)
200{
201 acpi_status status;
202 u32 result, capbuf[3];
203
204 support &= OSC_PCI_SUPPORT_MASKS;
205 support |= root->osc_support_set;
206
207 capbuf[OSC_QUERY_DWORD] = OSC_QUERY_ENABLE;
208 capbuf[OSC_SUPPORT_DWORD] = support;
209 if (control) {
210 *control &= OSC_PCI_CONTROL_MASKS;
211 capbuf[OSC_CONTROL_DWORD] = *control | root->osc_control_set;
212 } else {
213 /* Run _OSC query only with existing controls. */
214 capbuf[OSC_CONTROL_DWORD] = root->osc_control_set;
215 }
216
217 status = acpi_pci_run_osc(root->device->handle, capbuf, &result);
218 if (ACPI_SUCCESS(status)) {
219 root->osc_support_set = support;
220 if (control)
221 *control = result;
222 }
223 return status;
224}
225
226static acpi_status acpi_pci_osc_support(struct acpi_pci_root *root, u32 flags)
227{
228 acpi_status status;
229
230 mutex_lock(&osc_lock);
231 status = acpi_pci_query_osc(root, flags, NULL);
232 mutex_unlock(&osc_lock);
233 return status;
234}
235
236struct acpi_pci_root *acpi_pci_find_root(acpi_handle handle)
237{
238 struct acpi_pci_root *root;
239 struct acpi_device *device;
240
241 if (acpi_bus_get_device(handle, &device) ||
242 acpi_match_device_ids(device, root_device_ids))
243 return NULL;
244
245 root = acpi_driver_data(device);
246
247 return root;
248}
249EXPORT_SYMBOL_GPL(acpi_pci_find_root);
250
251struct acpi_handle_node {
252 struct list_head node;
253 acpi_handle handle;
254};
255
256/**
257 * acpi_get_pci_dev - convert ACPI CA handle to struct pci_dev
258 * @handle: the handle in question
259 *
260 * Given an ACPI CA handle, the desired PCI device is located in the
261 * list of PCI devices.
262 *
263 * If the device is found, its reference count is increased and this
264 * function returns a pointer to its data structure. The caller must
265 * decrement the reference count by calling pci_dev_put().
266 * If no device is found, %NULL is returned.
267 */
268struct pci_dev *acpi_get_pci_dev(acpi_handle handle)
269{
270 int dev, fn;
271 unsigned long long adr;
272 acpi_status status;
273 acpi_handle phandle;
274 struct pci_bus *pbus;
275 struct pci_dev *pdev = NULL;
276 struct acpi_handle_node *node, *tmp;
277 struct acpi_pci_root *root;
278 LIST_HEAD(device_list);
279
280 /*
281 * Walk up the ACPI CA namespace until we reach a PCI root bridge.
282 */
283 phandle = handle;
284 while (!acpi_is_root_bridge(phandle)) {
285 node = kzalloc(sizeof(struct acpi_handle_node), GFP_KERNEL);
286 if (!node)
287 goto out;
288
289 INIT_LIST_HEAD(&node->node);
290 node->handle = phandle;
291 list_add(&node->node, &device_list);
292
293 status = acpi_get_parent(phandle, &phandle);
294 if (ACPI_FAILURE(status))
295 goto out;
296 }
297
298 root = acpi_pci_find_root(phandle);
299 if (!root)
300 goto out;
301
302 pbus = root->bus;
303
304 /*
305 * Now, walk back down the PCI device tree until we return to our
306 * original handle. Assumes that everything between the PCI root
307 * bridge and the device we're looking for must be a P2P bridge.
308 */
309 list_for_each_entry(node, &device_list, node) {
310 acpi_handle hnd = node->handle;
311 status = acpi_evaluate_integer(hnd, "_ADR", NULL, &adr);
312 if (ACPI_FAILURE(status))
313 goto out;
314 dev = (adr >> 16) & 0xffff;
315 fn = adr & 0xffff;
316
317 pdev = pci_get_slot(pbus, PCI_DEVFN(dev, fn));
318 if (!pdev || hnd == handle)
319 break;
320
321 pbus = pdev->subordinate;
322 pci_dev_put(pdev);
323
324 /*
325 * This function may be called for a non-PCI device that has a
326 * PCI parent (eg. a disk under a PCI SATA controller). In that
327 * case pdev->subordinate will be NULL for the parent.
328 */
329 if (!pbus) {
330 dev_dbg(&pdev->dev, "Not a PCI-to-PCI bridge\n");
331 pdev = NULL;
332 break;
333 }
334 }
335out:
336 list_for_each_entry_safe(node, tmp, &device_list, node)
337 kfree(node);
338
339 return pdev;
340}
341EXPORT_SYMBOL_GPL(acpi_get_pci_dev);
342
343/**
344 * acpi_pci_osc_control_set - Request control of PCI root _OSC features.
345 * @handle: ACPI handle of a PCI root bridge (or PCIe Root Complex).
346 * @mask: Mask of _OSC bits to request control of, place to store control mask.
347 * @req: Mask of _OSC bits the control of is essential to the caller.
348 *
349 * Run _OSC query for @mask and if that is successful, compare the returned
350 * mask of control bits with @req. If all of the @req bits are set in the
351 * returned mask, run _OSC request for it.
352 *
353 * The variable at the @mask address may be modified regardless of whether or
354 * not the function returns success. On success it will contain the mask of
355 * _OSC bits the BIOS has granted control of, but its contents are meaningless
356 * on failure.
357 **/
358acpi_status acpi_pci_osc_control_set(acpi_handle handle, u32 *mask, u32 req)
359{
360 struct acpi_pci_root *root;
361 acpi_status status = AE_OK;
362 u32 ctrl, capbuf[3];
363
364 if (!mask)
365 return AE_BAD_PARAMETER;
366
367 ctrl = *mask & OSC_PCI_CONTROL_MASKS;
368 if ((ctrl & req) != req)
369 return AE_TYPE;
370
371 root = acpi_pci_find_root(handle);
372 if (!root)
373 return AE_NOT_EXIST;
374
375 mutex_lock(&osc_lock);
376
377 *mask = ctrl | root->osc_control_set;
378 /* No need to evaluate _OSC if the control was already granted. */
379 if ((root->osc_control_set & ctrl) == ctrl)
380 goto out;
381
382 /* Need to check the available controls bits before requesting them. */
383 while (*mask) {
384 status = acpi_pci_query_osc(root, root->osc_support_set, mask);
385 if (ACPI_FAILURE(status))
386 goto out;
387 if (ctrl == *mask)
388 break;
389 decode_osc_control(root, "platform does not support",
390 ctrl & ~(*mask));
391 ctrl = *mask;
392 }
393
394 if ((ctrl & req) != req) {
395 decode_osc_control(root, "not requesting control; platform does not support",
396 req & ~(ctrl));
397 status = AE_SUPPORT;
398 goto out;
399 }
400
401 capbuf[OSC_QUERY_DWORD] = 0;
402 capbuf[OSC_SUPPORT_DWORD] = root->osc_support_set;
403 capbuf[OSC_CONTROL_DWORD] = ctrl;
404 status = acpi_pci_run_osc(handle, capbuf, mask);
405 if (ACPI_SUCCESS(status))
406 root->osc_control_set = *mask;
407out:
408 mutex_unlock(&osc_lock);
409 return status;
410}
411EXPORT_SYMBOL(acpi_pci_osc_control_set);
412
413static void negotiate_os_control(struct acpi_pci_root *root, int *no_aspm,
414 bool is_pcie)
415{
416 u32 support, control, requested;
417 acpi_status status;
418 struct acpi_device *device = root->device;
419 acpi_handle handle = device->handle;
420
421 /*
422 * Apple always return failure on _OSC calls when _OSI("Darwin") has
423 * been called successfully. We know the feature set supported by the
424 * platform, so avoid calling _OSC at all
425 */
426 if (x86_apple_machine) {
427 root->osc_control_set = ~OSC_PCI_EXPRESS_PME_CONTROL;
428 decode_osc_control(root, "OS assumes control of",
429 root->osc_control_set);
430 return;
431 }
432
433 /*
434 * All supported architectures that use ACPI have support for
435 * PCI domains, so we indicate this in _OSC support capabilities.
436 */
437 support = OSC_PCI_SEGMENT_GROUPS_SUPPORT;
438 support |= OSC_PCI_HPX_TYPE_3_SUPPORT;
439 if (pci_ext_cfg_avail())
440 support |= OSC_PCI_EXT_CONFIG_SUPPORT;
441 if (pcie_aspm_support_enabled())
442 support |= OSC_PCI_ASPM_SUPPORT | OSC_PCI_CLOCK_PM_SUPPORT;
443 if (pci_msi_enabled())
444 support |= OSC_PCI_MSI_SUPPORT;
445 if (IS_ENABLED(CONFIG_PCIE_EDR))
446 support |= OSC_PCI_EDR_SUPPORT;
447
448 decode_osc_support(root, "OS supports", support);
449 status = acpi_pci_osc_support(root, support);
450 if (ACPI_FAILURE(status)) {
451 *no_aspm = 1;
452
453 /* _OSC is optional for PCI host bridges */
454 if ((status == AE_NOT_FOUND) && !is_pcie)
455 return;
456
457 dev_info(&device->dev, "_OSC failed (%s)%s\n",
458 acpi_format_exception(status),
459 pcie_aspm_support_enabled() ? "; disabling ASPM" : "");
460 return;
461 }
462
463 if (pcie_ports_disabled) {
464 dev_info(&device->dev, "PCIe port services disabled; not requesting _OSC control\n");
465 return;
466 }
467
468 if ((support & ACPI_PCIE_REQ_SUPPORT) != ACPI_PCIE_REQ_SUPPORT) {
469 decode_osc_support(root, "not requesting OS control; OS requires",
470 ACPI_PCIE_REQ_SUPPORT);
471 return;
472 }
473
474 control = OSC_PCI_EXPRESS_CAPABILITY_CONTROL
475 | OSC_PCI_EXPRESS_PME_CONTROL;
476
477 if (IS_ENABLED(CONFIG_PCIEASPM))
478 control |= OSC_PCI_EXPRESS_LTR_CONTROL;
479
480 if (IS_ENABLED(CONFIG_HOTPLUG_PCI_PCIE))
481 control |= OSC_PCI_EXPRESS_NATIVE_HP_CONTROL;
482
483 if (IS_ENABLED(CONFIG_HOTPLUG_PCI_SHPC))
484 control |= OSC_PCI_SHPC_NATIVE_HP_CONTROL;
485
486 if (pci_aer_available())
487 control |= OSC_PCI_EXPRESS_AER_CONTROL;
488
489 /*
490 * Per the Downstream Port Containment Related Enhancements ECN to
491 * the PCI Firmware Spec, r3.2, sec 4.5.1, table 4-5,
492 * OSC_PCI_EXPRESS_DPC_CONTROL indicates the OS supports both DPC
493 * and EDR.
494 */
495 if (IS_ENABLED(CONFIG_PCIE_DPC) && IS_ENABLED(CONFIG_PCIE_EDR))
496 control |= OSC_PCI_EXPRESS_DPC_CONTROL;
497
498 requested = control;
499 status = acpi_pci_osc_control_set(handle, &control,
500 OSC_PCI_EXPRESS_CAPABILITY_CONTROL);
501 if (ACPI_SUCCESS(status)) {
502 decode_osc_control(root, "OS now controls", control);
503 if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_ASPM) {
504 /*
505 * We have ASPM control, but the FADT indicates that
506 * it's unsupported. Leave existing configuration
507 * intact and prevent the OS from touching it.
508 */
509 dev_info(&device->dev, "FADT indicates ASPM is unsupported, using BIOS configuration\n");
510 *no_aspm = 1;
511 }
512 } else {
513 decode_osc_control(root, "OS requested", requested);
514 decode_osc_control(root, "platform willing to grant", control);
515 dev_info(&device->dev, "_OSC failed (%s); disabling ASPM\n",
516 acpi_format_exception(status));
517
518 /*
519 * We want to disable ASPM here, but aspm_disabled
520 * needs to remain in its state from boot so that we
521 * properly handle PCIe 1.1 devices. So we set this
522 * flag here, to defer the action until after the ACPI
523 * root scan.
524 */
525 *no_aspm = 1;
526 }
527}
528
529static int acpi_pci_root_add(struct acpi_device *device,
530 const struct acpi_device_id *not_used)
531{
532 unsigned long long segment, bus;
533 acpi_status status;
534 int result;
535 struct acpi_pci_root *root;
536 acpi_handle handle = device->handle;
537 int no_aspm = 0;
538 bool hotadd = system_state == SYSTEM_RUNNING;
539 bool is_pcie;
540
541 root = kzalloc(sizeof(struct acpi_pci_root), GFP_KERNEL);
542 if (!root)
543 return -ENOMEM;
544
545 segment = 0;
546 status = acpi_evaluate_integer(handle, METHOD_NAME__SEG, NULL,
547 &segment);
548 if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
549 dev_err(&device->dev, "can't evaluate _SEG\n");
550 result = -ENODEV;
551 goto end;
552 }
553
554 /* Check _CRS first, then _BBN. If no _BBN, default to zero. */
555 root->secondary.flags = IORESOURCE_BUS;
556 status = try_get_root_bridge_busnr(handle, &root->secondary);
557 if (ACPI_FAILURE(status)) {
558 /*
559 * We need both the start and end of the downstream bus range
560 * to interpret _CBA (MMCONFIG base address), so it really is
561 * supposed to be in _CRS. If we don't find it there, all we
562 * can do is assume [_BBN-0xFF] or [0-0xFF].
563 */
564 root->secondary.end = 0xFF;
565 dev_warn(&device->dev,
566 FW_BUG "no secondary bus range in _CRS\n");
567 status = acpi_evaluate_integer(handle, METHOD_NAME__BBN,
568 NULL, &bus);
569 if (ACPI_SUCCESS(status))
570 root->secondary.start = bus;
571 else if (status == AE_NOT_FOUND)
572 root->secondary.start = 0;
573 else {
574 dev_err(&device->dev, "can't evaluate _BBN\n");
575 result = -ENODEV;
576 goto end;
577 }
578 }
579
580 root->device = device;
581 root->segment = segment & 0xFFFF;
582 strcpy(acpi_device_name(device), ACPI_PCI_ROOT_DEVICE_NAME);
583 strcpy(acpi_device_class(device), ACPI_PCI_ROOT_CLASS);
584 device->driver_data = root;
585
586 if (hotadd && dmar_device_add(handle)) {
587 result = -ENXIO;
588 goto end;
589 }
590
591 pr_info(PREFIX "%s [%s] (domain %04x %pR)\n",
592 acpi_device_name(device), acpi_device_bid(device),
593 root->segment, &root->secondary);
594
595 root->mcfg_addr = acpi_pci_root_get_mcfg_addr(handle);
596
597 is_pcie = strcmp(acpi_device_hid(device), "PNP0A08") == 0;
598 negotiate_os_control(root, &no_aspm, is_pcie);
599
600 /*
601 * TBD: Need PCI interface for enumeration/configuration of roots.
602 */
603
604 /*
605 * Scan the Root Bridge
606 * --------------------
607 * Must do this prior to any attempt to bind the root device, as the
608 * PCI namespace does not get created until this call is made (and
609 * thus the root bridge's pci_dev does not exist).
610 */
611 root->bus = pci_acpi_scan_root(root);
612 if (!root->bus) {
613 dev_err(&device->dev,
614 "Bus %04x:%02x not present in PCI namespace\n",
615 root->segment, (unsigned int)root->secondary.start);
616 device->driver_data = NULL;
617 result = -ENODEV;
618 goto remove_dmar;
619 }
620
621 if (no_aspm)
622 pcie_no_aspm();
623
624 pci_acpi_add_bus_pm_notifier(device);
625 device_set_wakeup_capable(root->bus->bridge, device->wakeup.flags.valid);
626
627 if (hotadd) {
628 pcibios_resource_survey_bus(root->bus);
629 pci_assign_unassigned_root_bus_resources(root->bus);
630 /*
631 * This is only called for the hotadd case. For the boot-time
632 * case, we need to wait until after PCI initialization in
633 * order to deal with IOAPICs mapped in on a PCI BAR.
634 *
635 * This is currently x86-specific, because acpi_ioapic_add()
636 * is an empty function without CONFIG_ACPI_HOTPLUG_IOAPIC.
637 * And CONFIG_ACPI_HOTPLUG_IOAPIC depends on CONFIG_X86_IO_APIC
638 * (see drivers/acpi/Kconfig).
639 */
640 acpi_ioapic_add(root->device->handle);
641 }
642
643 pci_lock_rescan_remove();
644 pci_bus_add_devices(root->bus);
645 pci_unlock_rescan_remove();
646 return 1;
647
648remove_dmar:
649 if (hotadd)
650 dmar_device_remove(handle);
651end:
652 kfree(root);
653 return result;
654}
655
656static void acpi_pci_root_remove(struct acpi_device *device)
657{
658 struct acpi_pci_root *root = acpi_driver_data(device);
659
660 pci_lock_rescan_remove();
661
662 pci_stop_root_bus(root->bus);
663
664 pci_ioapic_remove(root);
665 device_set_wakeup_capable(root->bus->bridge, false);
666 pci_acpi_remove_bus_pm_notifier(device);
667
668 pci_remove_root_bus(root->bus);
669 WARN_ON(acpi_ioapic_remove(root));
670
671 dmar_device_remove(device->handle);
672
673 pci_unlock_rescan_remove();
674
675 kfree(root);
676}
677
678/*
679 * Following code to support acpi_pci_root_create() is copied from
680 * arch/x86/pci/acpi.c and modified so it could be reused by x86, IA64
681 * and ARM64.
682 */
683static void acpi_pci_root_validate_resources(struct device *dev,
684 struct list_head *resources,
685 unsigned long type)
686{
687 LIST_HEAD(list);
688 struct resource *res1, *res2, *root = NULL;
689 struct resource_entry *tmp, *entry, *entry2;
690
691 BUG_ON((type & (IORESOURCE_MEM | IORESOURCE_IO)) == 0);
692 root = (type & IORESOURCE_MEM) ? &iomem_resource : &ioport_resource;
693
694 list_splice_init(resources, &list);
695 resource_list_for_each_entry_safe(entry, tmp, &list) {
696 bool free = false;
697 resource_size_t end;
698
699 res1 = entry->res;
700 if (!(res1->flags & type))
701 goto next;
702
703 /* Exclude non-addressable range or non-addressable portion */
704 end = min(res1->end, root->end);
705 if (end <= res1->start) {
706 dev_info(dev, "host bridge window %pR (ignored, not CPU addressable)\n",
707 res1);
708 free = true;
709 goto next;
710 } else if (res1->end != end) {
711 dev_info(dev, "host bridge window %pR ([%#llx-%#llx] ignored, not CPU addressable)\n",
712 res1, (unsigned long long)end + 1,
713 (unsigned long long)res1->end);
714 res1->end = end;
715 }
716
717 resource_list_for_each_entry(entry2, resources) {
718 res2 = entry2->res;
719 if (!(res2->flags & type))
720 continue;
721
722 /*
723 * I don't like throwing away windows because then
724 * our resources no longer match the ACPI _CRS, but
725 * the kernel resource tree doesn't allow overlaps.
726 */
727 if (resource_overlaps(res1, res2)) {
728 res2->start = min(res1->start, res2->start);
729 res2->end = max(res1->end, res2->end);
730 dev_info(dev, "host bridge window expanded to %pR; %pR ignored\n",
731 res2, res1);
732 free = true;
733 goto next;
734 }
735 }
736
737next:
738 resource_list_del(entry);
739 if (free)
740 resource_list_free_entry(entry);
741 else
742 resource_list_add_tail(entry, resources);
743 }
744}
745
746static void acpi_pci_root_remap_iospace(struct fwnode_handle *fwnode,
747 struct resource_entry *entry)
748{
749#ifdef PCI_IOBASE
750 struct resource *res = entry->res;
751 resource_size_t cpu_addr = res->start;
752 resource_size_t pci_addr = cpu_addr - entry->offset;
753 resource_size_t length = resource_size(res);
754 unsigned long port;
755
756 if (pci_register_io_range(fwnode, cpu_addr, length))
757 goto err;
758
759 port = pci_address_to_pio(cpu_addr);
760 if (port == (unsigned long)-1)
761 goto err;
762
763 res->start = port;
764 res->end = port + length - 1;
765 entry->offset = port - pci_addr;
766
767 if (pci_remap_iospace(res, cpu_addr) < 0)
768 goto err;
769
770 pr_info("Remapped I/O %pa to %pR\n", &cpu_addr, res);
771 return;
772err:
773 res->flags |= IORESOURCE_DISABLED;
774#endif
775}
776
777int acpi_pci_probe_root_resources(struct acpi_pci_root_info *info)
778{
779 int ret;
780 struct list_head *list = &info->resources;
781 struct acpi_device *device = info->bridge;
782 struct resource_entry *entry, *tmp;
783 unsigned long flags;
784
785 flags = IORESOURCE_IO | IORESOURCE_MEM | IORESOURCE_MEM_8AND16BIT;
786 ret = acpi_dev_get_resources(device, list,
787 acpi_dev_filter_resource_type_cb,
788 (void *)flags);
789 if (ret < 0)
790 dev_warn(&device->dev,
791 "failed to parse _CRS method, error code %d\n", ret);
792 else if (ret == 0)
793 dev_dbg(&device->dev,
794 "no IO and memory resources present in _CRS\n");
795 else {
796 resource_list_for_each_entry_safe(entry, tmp, list) {
797 if (entry->res->flags & IORESOURCE_IO)
798 acpi_pci_root_remap_iospace(&device->fwnode,
799 entry);
800
801 if (entry->res->flags & IORESOURCE_DISABLED)
802 resource_list_destroy_entry(entry);
803 else
804 entry->res->name = info->name;
805 }
806 acpi_pci_root_validate_resources(&device->dev, list,
807 IORESOURCE_MEM);
808 acpi_pci_root_validate_resources(&device->dev, list,
809 IORESOURCE_IO);
810 }
811
812 return ret;
813}
814
815static void pci_acpi_root_add_resources(struct acpi_pci_root_info *info)
816{
817 struct resource_entry *entry, *tmp;
818 struct resource *res, *conflict, *root = NULL;
819
820 resource_list_for_each_entry_safe(entry, tmp, &info->resources) {
821 res = entry->res;
822 if (res->flags & IORESOURCE_MEM)
823 root = &iomem_resource;
824 else if (res->flags & IORESOURCE_IO)
825 root = &ioport_resource;
826 else
827 continue;
828
829 /*
830 * Some legacy x86 host bridge drivers use iomem_resource and
831 * ioport_resource as default resource pool, skip it.
832 */
833 if (res == root)
834 continue;
835
836 conflict = insert_resource_conflict(root, res);
837 if (conflict) {
838 dev_info(&info->bridge->dev,
839 "ignoring host bridge window %pR (conflicts with %s %pR)\n",
840 res, conflict->name, conflict);
841 resource_list_destroy_entry(entry);
842 }
843 }
844}
845
846static void __acpi_pci_root_release_info(struct acpi_pci_root_info *info)
847{
848 struct resource *res;
849 struct resource_entry *entry, *tmp;
850
851 if (!info)
852 return;
853
854 resource_list_for_each_entry_safe(entry, tmp, &info->resources) {
855 res = entry->res;
856 if (res->parent &&
857 (res->flags & (IORESOURCE_MEM | IORESOURCE_IO)))
858 release_resource(res);
859 resource_list_destroy_entry(entry);
860 }
861
862 info->ops->release_info(info);
863}
864
865static void acpi_pci_root_release_info(struct pci_host_bridge *bridge)
866{
867 struct resource *res;
868 struct resource_entry *entry;
869
870 resource_list_for_each_entry(entry, &bridge->windows) {
871 res = entry->res;
872 if (res->flags & IORESOURCE_IO)
873 pci_unmap_iospace(res);
874 if (res->parent &&
875 (res->flags & (IORESOURCE_MEM | IORESOURCE_IO)))
876 release_resource(res);
877 }
878 __acpi_pci_root_release_info(bridge->release_data);
879}
880
881struct pci_bus *acpi_pci_root_create(struct acpi_pci_root *root,
882 struct acpi_pci_root_ops *ops,
883 struct acpi_pci_root_info *info,
884 void *sysdata)
885{
886 int ret, busnum = root->secondary.start;
887 struct acpi_device *device = root->device;
888 int node = acpi_get_node(device->handle);
889 struct pci_bus *bus;
890 struct pci_host_bridge *host_bridge;
891 union acpi_object *obj;
892
893 info->root = root;
894 info->bridge = device;
895 info->ops = ops;
896 INIT_LIST_HEAD(&info->resources);
897 snprintf(info->name, sizeof(info->name), "PCI Bus %04x:%02x",
898 root->segment, busnum);
899
900 if (ops->init_info && ops->init_info(info))
901 goto out_release_info;
902 if (ops->prepare_resources)
903 ret = ops->prepare_resources(info);
904 else
905 ret = acpi_pci_probe_root_resources(info);
906 if (ret < 0)
907 goto out_release_info;
908
909 pci_acpi_root_add_resources(info);
910 pci_add_resource(&info->resources, &root->secondary);
911 bus = pci_create_root_bus(NULL, busnum, ops->pci_ops,
912 sysdata, &info->resources);
913 if (!bus)
914 goto out_release_info;
915
916 host_bridge = to_pci_host_bridge(bus->bridge);
917 if (!(root->osc_control_set & OSC_PCI_EXPRESS_NATIVE_HP_CONTROL))
918 host_bridge->native_pcie_hotplug = 0;
919 if (!(root->osc_control_set & OSC_PCI_SHPC_NATIVE_HP_CONTROL))
920 host_bridge->native_shpc_hotplug = 0;
921 if (!(root->osc_control_set & OSC_PCI_EXPRESS_AER_CONTROL))
922 host_bridge->native_aer = 0;
923 if (!(root->osc_control_set & OSC_PCI_EXPRESS_PME_CONTROL))
924 host_bridge->native_pme = 0;
925 if (!(root->osc_control_set & OSC_PCI_EXPRESS_LTR_CONTROL))
926 host_bridge->native_ltr = 0;
927 if (!(root->osc_control_set & OSC_PCI_EXPRESS_DPC_CONTROL))
928 host_bridge->native_dpc = 0;
929
930 /*
931 * Evaluate the "PCI Boot Configuration" _DSM Function. If it
932 * exists and returns 0, we must preserve any PCI resource
933 * assignments made by firmware for this host bridge.
934 */
935 obj = acpi_evaluate_dsm(ACPI_HANDLE(bus->bridge), &pci_acpi_dsm_guid, 1,
936 DSM_PCI_PRESERVE_BOOT_CONFIG, NULL);
937 if (obj && obj->type == ACPI_TYPE_INTEGER && obj->integer.value == 0)
938 host_bridge->preserve_config = 1;
939 ACPI_FREE(obj);
940
941 pci_scan_child_bus(bus);
942 pci_set_host_bridge_release(host_bridge, acpi_pci_root_release_info,
943 info);
944 if (node != NUMA_NO_NODE)
945 dev_printk(KERN_DEBUG, &bus->dev, "on NUMA node %d\n", node);
946 return bus;
947
948out_release_info:
949 __acpi_pci_root_release_info(info);
950 return NULL;
951}
952
953void __init acpi_pci_root_init(void)
954{
955 acpi_hest_init();
956 if (acpi_pci_disabled)
957 return;
958
959 pci_acpi_crs_quirks();
960 acpi_scan_add_handler_with_hotplug(&pci_root_handler, "pci_root");
961}
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 "internal.h"
26
27#define ACPI_PCI_ROOT_CLASS "pci_bridge"
28#define ACPI_PCI_ROOT_DEVICE_NAME "PCI Root Bridge"
29static int acpi_pci_root_add(struct acpi_device *device,
30 const struct acpi_device_id *not_used);
31static void acpi_pci_root_remove(struct acpi_device *device);
32
33static int acpi_pci_root_scan_dependent(struct acpi_device *adev)
34{
35 acpiphp_check_host_bridge(adev);
36 return 0;
37}
38
39#define ACPI_PCIE_REQ_SUPPORT (OSC_PCI_EXT_CONFIG_SUPPORT \
40 | OSC_PCI_ASPM_SUPPORT \
41 | OSC_PCI_CLOCK_PM_SUPPORT \
42 | OSC_PCI_MSI_SUPPORT)
43
44static const struct acpi_device_id root_device_ids[] = {
45 {"PNP0A03", 0},
46 {"", 0},
47};
48
49static struct acpi_scan_handler pci_root_handler = {
50 .ids = root_device_ids,
51 .attach = acpi_pci_root_add,
52 .detach = acpi_pci_root_remove,
53 .hotplug = {
54 .enabled = true,
55 .scan_dependent = acpi_pci_root_scan_dependent,
56 },
57};
58
59/**
60 * acpi_is_root_bridge - determine whether an ACPI CA node is a PCI root bridge
61 * @handle: the ACPI CA node in question.
62 *
63 * Note: we could make this API take a struct acpi_device * instead, but
64 * for now, it's more convenient to operate on an acpi_handle.
65 */
66int acpi_is_root_bridge(acpi_handle handle)
67{
68 struct acpi_device *device = acpi_fetch_acpi_dev(handle);
69 int ret;
70
71 if (!device)
72 return 0;
73
74 ret = acpi_match_device_ids(device, root_device_ids);
75 if (ret)
76 return 0;
77 else
78 return 1;
79}
80EXPORT_SYMBOL_GPL(acpi_is_root_bridge);
81
82static acpi_status
83get_root_bridge_busnr_callback(struct acpi_resource *resource, void *data)
84{
85 struct resource *res = data;
86 struct acpi_resource_address64 address;
87 acpi_status status;
88
89 status = acpi_resource_to_address64(resource, &address);
90 if (ACPI_FAILURE(status))
91 return AE_OK;
92
93 if ((address.address.address_length > 0) &&
94 (address.resource_type == ACPI_BUS_NUMBER_RANGE)) {
95 res->start = address.address.minimum;
96 res->end = address.address.minimum + address.address.address_length - 1;
97 }
98
99 return AE_OK;
100}
101
102static acpi_status try_get_root_bridge_busnr(acpi_handle handle,
103 struct resource *res)
104{
105 acpi_status status;
106
107 res->start = -1;
108 status =
109 acpi_walk_resources(handle, METHOD_NAME__CRS,
110 get_root_bridge_busnr_callback, res);
111 if (ACPI_FAILURE(status))
112 return status;
113 if (res->start == -1)
114 return AE_ERROR;
115 return AE_OK;
116}
117
118struct pci_osc_bit_struct {
119 u32 bit;
120 char *desc;
121};
122
123static struct pci_osc_bit_struct pci_osc_support_bit[] = {
124 { OSC_PCI_EXT_CONFIG_SUPPORT, "ExtendedConfig" },
125 { OSC_PCI_ASPM_SUPPORT, "ASPM" },
126 { OSC_PCI_CLOCK_PM_SUPPORT, "ClockPM" },
127 { OSC_PCI_SEGMENT_GROUPS_SUPPORT, "Segments" },
128 { OSC_PCI_MSI_SUPPORT, "MSI" },
129 { OSC_PCI_EDR_SUPPORT, "EDR" },
130 { OSC_PCI_HPX_TYPE_3_SUPPORT, "HPX-Type3" },
131};
132
133static struct pci_osc_bit_struct pci_osc_control_bit[] = {
134 { OSC_PCI_EXPRESS_NATIVE_HP_CONTROL, "PCIeHotplug" },
135 { OSC_PCI_SHPC_NATIVE_HP_CONTROL, "SHPCHotplug" },
136 { OSC_PCI_EXPRESS_PME_CONTROL, "PME" },
137 { OSC_PCI_EXPRESS_AER_CONTROL, "AER" },
138 { OSC_PCI_EXPRESS_CAPABILITY_CONTROL, "PCIeCapability" },
139 { OSC_PCI_EXPRESS_LTR_CONTROL, "LTR" },
140 { OSC_PCI_EXPRESS_DPC_CONTROL, "DPC" },
141};
142
143static struct pci_osc_bit_struct cxl_osc_support_bit[] = {
144 { OSC_CXL_1_1_PORT_REG_ACCESS_SUPPORT, "CXL11PortRegAccess" },
145 { OSC_CXL_2_0_PORT_DEV_REG_ACCESS_SUPPORT, "CXL20PortDevRegAccess" },
146 { OSC_CXL_PROTOCOL_ERR_REPORTING_SUPPORT, "CXLProtocolErrorReporting" },
147 { OSC_CXL_NATIVE_HP_SUPPORT, "CXLNativeHotPlug" },
148};
149
150static struct pci_osc_bit_struct cxl_osc_control_bit[] = {
151 { OSC_CXL_ERROR_REPORTING_CONTROL, "CXLMemErrorReporting" },
152};
153
154static void decode_osc_bits(struct acpi_pci_root *root, char *msg, u32 word,
155 struct pci_osc_bit_struct *table, int size)
156{
157 char buf[80];
158 int i, len = 0;
159 struct pci_osc_bit_struct *entry;
160
161 buf[0] = '\0';
162 for (i = 0, entry = table; i < size; i++, entry++)
163 if (word & entry->bit)
164 len += scnprintf(buf + len, sizeof(buf) - len, "%s%s",
165 len ? " " : "", entry->desc);
166
167 dev_info(&root->device->dev, "_OSC: %s [%s]\n", msg, buf);
168}
169
170static void decode_osc_support(struct acpi_pci_root *root, char *msg, u32 word)
171{
172 decode_osc_bits(root, msg, word, pci_osc_support_bit,
173 ARRAY_SIZE(pci_osc_support_bit));
174}
175
176static void decode_osc_control(struct acpi_pci_root *root, char *msg, u32 word)
177{
178 decode_osc_bits(root, msg, word, pci_osc_control_bit,
179 ARRAY_SIZE(pci_osc_control_bit));
180}
181
182static void decode_cxl_osc_support(struct acpi_pci_root *root, char *msg, u32 word)
183{
184 decode_osc_bits(root, msg, word, cxl_osc_support_bit,
185 ARRAY_SIZE(cxl_osc_support_bit));
186}
187
188static void decode_cxl_osc_control(struct acpi_pci_root *root, char *msg, u32 word)
189{
190 decode_osc_bits(root, msg, word, cxl_osc_control_bit,
191 ARRAY_SIZE(cxl_osc_control_bit));
192}
193
194static inline bool is_pcie(struct acpi_pci_root *root)
195{
196 return root->bridge_type == ACPI_BRIDGE_TYPE_PCIE;
197}
198
199static inline bool is_cxl(struct acpi_pci_root *root)
200{
201 return root->bridge_type == ACPI_BRIDGE_TYPE_CXL;
202}
203
204static u8 pci_osc_uuid_str[] = "33DB4D5B-1FF7-401C-9657-7441C03DD766";
205static u8 cxl_osc_uuid_str[] = "68F2D50B-C469-4d8A-BD3D-941A103FD3FC";
206
207static char *to_uuid(struct acpi_pci_root *root)
208{
209 if (is_cxl(root))
210 return cxl_osc_uuid_str;
211 return pci_osc_uuid_str;
212}
213
214static int cap_length(struct acpi_pci_root *root)
215{
216 if (is_cxl(root))
217 return sizeof(u32) * OSC_CXL_CAPABILITY_DWORDS;
218 return sizeof(u32) * OSC_PCI_CAPABILITY_DWORDS;
219}
220
221static acpi_status acpi_pci_run_osc(struct acpi_pci_root *root,
222 const u32 *capbuf, u32 *pci_control,
223 u32 *cxl_control)
224{
225 struct acpi_osc_context context = {
226 .uuid_str = to_uuid(root),
227 .rev = 1,
228 .cap.length = cap_length(root),
229 .cap.pointer = (void *)capbuf,
230 };
231 acpi_status status;
232
233 status = acpi_run_osc(root->device->handle, &context);
234 if (ACPI_SUCCESS(status)) {
235 *pci_control = acpi_osc_ctx_get_pci_control(&context);
236 if (is_cxl(root))
237 *cxl_control = acpi_osc_ctx_get_cxl_control(&context);
238 kfree(context.ret.pointer);
239 }
240 return status;
241}
242
243static acpi_status acpi_pci_query_osc(struct acpi_pci_root *root, u32 support,
244 u32 *control, u32 cxl_support,
245 u32 *cxl_control)
246{
247 acpi_status status;
248 u32 pci_result, cxl_result, capbuf[OSC_CXL_CAPABILITY_DWORDS];
249
250 support |= root->osc_support_set;
251
252 capbuf[OSC_QUERY_DWORD] = OSC_QUERY_ENABLE;
253 capbuf[OSC_SUPPORT_DWORD] = support;
254 capbuf[OSC_CONTROL_DWORD] = *control | root->osc_control_set;
255
256 if (is_cxl(root)) {
257 cxl_support |= root->osc_ext_support_set;
258 capbuf[OSC_EXT_SUPPORT_DWORD] = cxl_support;
259 capbuf[OSC_EXT_CONTROL_DWORD] = *cxl_control | root->osc_ext_control_set;
260 }
261
262retry:
263 status = acpi_pci_run_osc(root, capbuf, &pci_result, &cxl_result);
264 if (ACPI_SUCCESS(status)) {
265 root->osc_support_set = support;
266 *control = pci_result;
267 if (is_cxl(root)) {
268 root->osc_ext_support_set = cxl_support;
269 *cxl_control = cxl_result;
270 }
271 } else if (is_cxl(root)) {
272 /*
273 * CXL _OSC is optional on CXL 1.1 hosts. Fall back to PCIe _OSC
274 * upon any failure using CXL _OSC.
275 */
276 root->bridge_type = ACPI_BRIDGE_TYPE_PCIE;
277 goto retry;
278 }
279 return status;
280}
281
282struct acpi_pci_root *acpi_pci_find_root(acpi_handle handle)
283{
284 struct acpi_device *device = acpi_fetch_acpi_dev(handle);
285 struct acpi_pci_root *root;
286
287 if (!device || acpi_match_device_ids(device, root_device_ids))
288 return NULL;
289
290 root = acpi_driver_data(device);
291
292 return root;
293}
294EXPORT_SYMBOL_GPL(acpi_pci_find_root);
295
296struct acpi_handle_node {
297 struct list_head node;
298 acpi_handle handle;
299};
300
301/**
302 * acpi_get_pci_dev - convert ACPI CA handle to struct pci_dev
303 * @handle: the handle in question
304 *
305 * Given an ACPI CA handle, the desired PCI device is located in the
306 * list of PCI devices.
307 *
308 * If the device is found, its reference count is increased and this
309 * function returns a pointer to its data structure. The caller must
310 * decrement the reference count by calling pci_dev_put().
311 * If no device is found, %NULL is returned.
312 */
313struct pci_dev *acpi_get_pci_dev(acpi_handle handle)
314{
315 struct acpi_device *adev = acpi_fetch_acpi_dev(handle);
316 struct acpi_device_physical_node *pn;
317 struct pci_dev *pci_dev = NULL;
318
319 if (!adev)
320 return NULL;
321
322 mutex_lock(&adev->physical_node_lock);
323
324 list_for_each_entry(pn, &adev->physical_node_list, node) {
325 if (dev_is_pci(pn->dev)) {
326 get_device(pn->dev);
327 pci_dev = to_pci_dev(pn->dev);
328 break;
329 }
330 }
331
332 mutex_unlock(&adev->physical_node_lock);
333
334 return pci_dev;
335}
336EXPORT_SYMBOL_GPL(acpi_get_pci_dev);
337
338/**
339 * acpi_pci_osc_control_set - Request control of PCI root _OSC features.
340 * @handle: ACPI handle of a PCI root bridge (or PCIe Root Complex).
341 * @mask: Mask of _OSC bits to request control of, place to store control mask.
342 * @support: _OSC supported capability.
343 * @cxl_mask: Mask of CXL _OSC control bits, place to store control mask.
344 * @cxl_support: CXL _OSC supported capability.
345 *
346 * Run _OSC query for @mask and if that is successful, compare the returned
347 * mask of control bits with @req. If all of the @req bits are set in the
348 * returned mask, run _OSC request for it.
349 *
350 * The variable at the @mask address may be modified regardless of whether or
351 * not the function returns success. On success it will contain the mask of
352 * _OSC bits the BIOS has granted control of, but its contents are meaningless
353 * on failure.
354 **/
355static acpi_status acpi_pci_osc_control_set(acpi_handle handle, u32 *mask,
356 u32 support, u32 *cxl_mask,
357 u32 cxl_support)
358{
359 u32 req = OSC_PCI_EXPRESS_CAPABILITY_CONTROL;
360 struct acpi_pci_root *root;
361 acpi_status status;
362 u32 ctrl, cxl_ctrl = 0, capbuf[OSC_CXL_CAPABILITY_DWORDS];
363
364 if (!mask)
365 return AE_BAD_PARAMETER;
366
367 root = acpi_pci_find_root(handle);
368 if (!root)
369 return AE_NOT_EXIST;
370
371 ctrl = *mask;
372 *mask |= root->osc_control_set;
373
374 if (is_cxl(root)) {
375 cxl_ctrl = *cxl_mask;
376 *cxl_mask |= root->osc_ext_control_set;
377 }
378
379 /* Need to check the available controls bits before requesting them. */
380 do {
381 u32 pci_missing = 0, cxl_missing = 0;
382
383 status = acpi_pci_query_osc(root, support, mask, cxl_support,
384 cxl_mask);
385 if (ACPI_FAILURE(status))
386 return status;
387 if (is_cxl(root)) {
388 if (ctrl == *mask && cxl_ctrl == *cxl_mask)
389 break;
390 pci_missing = ctrl & ~(*mask);
391 cxl_missing = cxl_ctrl & ~(*cxl_mask);
392 } else {
393 if (ctrl == *mask)
394 break;
395 pci_missing = ctrl & ~(*mask);
396 }
397 if (pci_missing)
398 decode_osc_control(root, "platform does not support",
399 pci_missing);
400 if (cxl_missing)
401 decode_cxl_osc_control(root, "CXL platform does not support",
402 cxl_missing);
403 ctrl = *mask;
404 cxl_ctrl = *cxl_mask;
405 } while (*mask || *cxl_mask);
406
407 /* No need to request _OSC if the control was already granted. */
408 if ((root->osc_control_set & ctrl) == ctrl &&
409 (root->osc_ext_control_set & cxl_ctrl) == cxl_ctrl)
410 return AE_OK;
411
412 if ((ctrl & req) != req) {
413 decode_osc_control(root, "not requesting control; platform does not support",
414 req & ~(ctrl));
415 return AE_SUPPORT;
416 }
417
418 capbuf[OSC_QUERY_DWORD] = 0;
419 capbuf[OSC_SUPPORT_DWORD] = root->osc_support_set;
420 capbuf[OSC_CONTROL_DWORD] = ctrl;
421 if (is_cxl(root)) {
422 capbuf[OSC_EXT_SUPPORT_DWORD] = root->osc_ext_support_set;
423 capbuf[OSC_EXT_CONTROL_DWORD] = cxl_ctrl;
424 }
425
426 status = acpi_pci_run_osc(root, capbuf, mask, cxl_mask);
427 if (ACPI_FAILURE(status))
428 return status;
429
430 root->osc_control_set = *mask;
431 root->osc_ext_control_set = *cxl_mask;
432 return AE_OK;
433}
434
435static u32 calculate_support(void)
436{
437 u32 support;
438
439 /*
440 * All supported architectures that use ACPI have support for
441 * PCI domains, so we indicate this in _OSC support capabilities.
442 */
443 support = OSC_PCI_SEGMENT_GROUPS_SUPPORT;
444 support |= OSC_PCI_HPX_TYPE_3_SUPPORT;
445 if (pci_ext_cfg_avail())
446 support |= OSC_PCI_EXT_CONFIG_SUPPORT;
447 if (pcie_aspm_support_enabled())
448 support |= OSC_PCI_ASPM_SUPPORT | OSC_PCI_CLOCK_PM_SUPPORT;
449 if (pci_msi_enabled())
450 support |= OSC_PCI_MSI_SUPPORT;
451 if (IS_ENABLED(CONFIG_PCIE_EDR))
452 support |= OSC_PCI_EDR_SUPPORT;
453
454 return support;
455}
456
457/*
458 * Background on hotplug support, and making it depend on only
459 * CONFIG_HOTPLUG_PCI_PCIE vs. also considering CONFIG_MEMORY_HOTPLUG:
460 *
461 * CONFIG_ACPI_HOTPLUG_MEMORY does depend on CONFIG_MEMORY_HOTPLUG, but
462 * there is no existing _OSC for memory hotplug support. The reason is that
463 * ACPI memory hotplug requires the OS to acknowledge / coordinate with
464 * memory plug events via a scan handler. On the CXL side the equivalent
465 * would be if Linux supported the Mechanical Retention Lock [1], or
466 * otherwise had some coordination for the driver of a PCI device
467 * undergoing hotplug to be consulted on whether the hotplug should
468 * proceed or not.
469 *
470 * The concern is that if Linux says no to supporting CXL hotplug then
471 * the BIOS may say no to giving the OS hotplug control of any other PCIe
472 * device. So the question here is not whether hotplug is enabled, it's
473 * whether it is handled natively by the at all OS, and if
474 * CONFIG_HOTPLUG_PCI_PCIE is enabled then the answer is "yes".
475 *
476 * Otherwise, the plan for CXL coordinated remove, since the kernel does
477 * not support blocking hotplug, is to require the memory device to be
478 * disabled before hotplug is attempted. When CONFIG_MEMORY_HOTPLUG is
479 * disabled that step will fail and the remove attempt cancelled by the
480 * user. If that is not honored and the card is removed anyway then it
481 * does not matter if CONFIG_MEMORY_HOTPLUG is enabled or not, it will
482 * cause a crash and other badness.
483 *
484 * Therefore, just say yes to CXL hotplug and require removal to
485 * be coordinated by userspace unless and until the kernel grows better
486 * mechanisms for doing "managed" removal of devices in consultation with
487 * the driver.
488 *
489 * [1]: https://lore.kernel.org/all/20201122014203.4706-1-ashok.raj@intel.com/
490 */
491static u32 calculate_cxl_support(void)
492{
493 u32 support;
494
495 support = OSC_CXL_2_0_PORT_DEV_REG_ACCESS_SUPPORT;
496 support |= OSC_CXL_1_1_PORT_REG_ACCESS_SUPPORT;
497 if (pci_aer_available())
498 support |= OSC_CXL_PROTOCOL_ERR_REPORTING_SUPPORT;
499 if (IS_ENABLED(CONFIG_HOTPLUG_PCI_PCIE))
500 support |= OSC_CXL_NATIVE_HP_SUPPORT;
501
502 return support;
503}
504
505static u32 calculate_control(void)
506{
507 u32 control;
508
509 control = OSC_PCI_EXPRESS_CAPABILITY_CONTROL
510 | OSC_PCI_EXPRESS_PME_CONTROL;
511
512 if (IS_ENABLED(CONFIG_PCIEASPM))
513 control |= OSC_PCI_EXPRESS_LTR_CONTROL;
514
515 if (IS_ENABLED(CONFIG_HOTPLUG_PCI_PCIE))
516 control |= OSC_PCI_EXPRESS_NATIVE_HP_CONTROL;
517
518 if (IS_ENABLED(CONFIG_HOTPLUG_PCI_SHPC))
519 control |= OSC_PCI_SHPC_NATIVE_HP_CONTROL;
520
521 if (pci_aer_available())
522 control |= OSC_PCI_EXPRESS_AER_CONTROL;
523
524 /*
525 * Per the Downstream Port Containment Related Enhancements ECN to
526 * the PCI Firmware Spec, r3.2, sec 4.5.1, table 4-5,
527 * OSC_PCI_EXPRESS_DPC_CONTROL indicates the OS supports both DPC
528 * and EDR.
529 */
530 if (IS_ENABLED(CONFIG_PCIE_DPC) && IS_ENABLED(CONFIG_PCIE_EDR))
531 control |= OSC_PCI_EXPRESS_DPC_CONTROL;
532
533 return control;
534}
535
536static u32 calculate_cxl_control(void)
537{
538 u32 control = 0;
539
540 if (IS_ENABLED(CONFIG_MEMORY_FAILURE))
541 control |= OSC_CXL_ERROR_REPORTING_CONTROL;
542
543 return control;
544}
545
546static bool os_control_query_checks(struct acpi_pci_root *root, u32 support)
547{
548 struct acpi_device *device = root->device;
549
550 if (pcie_ports_disabled) {
551 dev_info(&device->dev, "PCIe port services disabled; not requesting _OSC control\n");
552 return false;
553 }
554
555 if ((support & ACPI_PCIE_REQ_SUPPORT) != ACPI_PCIE_REQ_SUPPORT) {
556 decode_osc_support(root, "not requesting OS control; OS requires",
557 ACPI_PCIE_REQ_SUPPORT);
558 return false;
559 }
560
561 return true;
562}
563
564static void negotiate_os_control(struct acpi_pci_root *root, int *no_aspm)
565{
566 u32 support, control = 0, requested = 0;
567 u32 cxl_support = 0, cxl_control = 0, cxl_requested = 0;
568 acpi_status status;
569 struct acpi_device *device = root->device;
570 acpi_handle handle = device->handle;
571
572 /*
573 * Apple always return failure on _OSC calls when _OSI("Darwin") has
574 * been called successfully. We know the feature set supported by the
575 * platform, so avoid calling _OSC at all
576 */
577 if (x86_apple_machine) {
578 root->osc_control_set = ~OSC_PCI_EXPRESS_PME_CONTROL;
579 decode_osc_control(root, "OS assumes control of",
580 root->osc_control_set);
581 return;
582 }
583
584 support = calculate_support();
585
586 decode_osc_support(root, "OS supports", support);
587
588 if (os_control_query_checks(root, support))
589 requested = control = calculate_control();
590
591 if (is_cxl(root)) {
592 cxl_support = calculate_cxl_support();
593 decode_cxl_osc_support(root, "OS supports", cxl_support);
594 cxl_requested = cxl_control = calculate_cxl_control();
595 }
596
597 status = acpi_pci_osc_control_set(handle, &control, support,
598 &cxl_control, cxl_support);
599 if (ACPI_SUCCESS(status)) {
600 if (control)
601 decode_osc_control(root, "OS now controls", control);
602 if (cxl_control)
603 decode_cxl_osc_control(root, "OS now controls",
604 cxl_control);
605
606 if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_ASPM) {
607 /*
608 * We have ASPM control, but the FADT indicates that
609 * it's unsupported. Leave existing configuration
610 * intact and prevent the OS from touching it.
611 */
612 dev_info(&device->dev, "FADT indicates ASPM is unsupported, using BIOS configuration\n");
613 *no_aspm = 1;
614 }
615 } else {
616 /*
617 * We want to disable ASPM here, but aspm_disabled
618 * needs to remain in its state from boot so that we
619 * properly handle PCIe 1.1 devices. So we set this
620 * flag here, to defer the action until after the ACPI
621 * root scan.
622 */
623 *no_aspm = 1;
624
625 /* _OSC is optional for PCI host bridges */
626 if (status == AE_NOT_FOUND && !is_pcie(root))
627 return;
628
629 if (control) {
630 decode_osc_control(root, "OS requested", requested);
631 decode_osc_control(root, "platform willing to grant", control);
632 }
633 if (cxl_control) {
634 decode_cxl_osc_control(root, "OS requested", cxl_requested);
635 decode_cxl_osc_control(root, "platform willing to grant",
636 cxl_control);
637 }
638
639 dev_info(&device->dev, "_OSC: platform retains control of PCIe features (%s)\n",
640 acpi_format_exception(status));
641 }
642}
643
644static int acpi_pci_root_add(struct acpi_device *device,
645 const struct acpi_device_id *not_used)
646{
647 unsigned long long segment, bus;
648 acpi_status status;
649 int result;
650 struct acpi_pci_root *root;
651 acpi_handle handle = device->handle;
652 int no_aspm = 0;
653 bool hotadd = system_state == SYSTEM_RUNNING;
654 const char *acpi_hid;
655
656 root = kzalloc(sizeof(struct acpi_pci_root), GFP_KERNEL);
657 if (!root)
658 return -ENOMEM;
659
660 segment = 0;
661 status = acpi_evaluate_integer(handle, METHOD_NAME__SEG, NULL,
662 &segment);
663 if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
664 dev_err(&device->dev, "can't evaluate _SEG\n");
665 result = -ENODEV;
666 goto end;
667 }
668
669 /* Check _CRS first, then _BBN. If no _BBN, default to zero. */
670 root->secondary.flags = IORESOURCE_BUS;
671 status = try_get_root_bridge_busnr(handle, &root->secondary);
672 if (ACPI_FAILURE(status)) {
673 /*
674 * We need both the start and end of the downstream bus range
675 * to interpret _CBA (MMCONFIG base address), so it really is
676 * supposed to be in _CRS. If we don't find it there, all we
677 * can do is assume [_BBN-0xFF] or [0-0xFF].
678 */
679 root->secondary.end = 0xFF;
680 dev_warn(&device->dev,
681 FW_BUG "no secondary bus range in _CRS\n");
682 status = acpi_evaluate_integer(handle, METHOD_NAME__BBN,
683 NULL, &bus);
684 if (ACPI_SUCCESS(status))
685 root->secondary.start = bus;
686 else if (status == AE_NOT_FOUND)
687 root->secondary.start = 0;
688 else {
689 dev_err(&device->dev, "can't evaluate _BBN\n");
690 result = -ENODEV;
691 goto end;
692 }
693 }
694
695 root->device = device;
696 root->segment = segment & 0xFFFF;
697 strcpy(acpi_device_name(device), ACPI_PCI_ROOT_DEVICE_NAME);
698 strcpy(acpi_device_class(device), ACPI_PCI_ROOT_CLASS);
699 device->driver_data = root;
700
701 if (hotadd && dmar_device_add(handle)) {
702 result = -ENXIO;
703 goto end;
704 }
705
706 pr_info("%s [%s] (domain %04x %pR)\n",
707 acpi_device_name(device), acpi_device_bid(device),
708 root->segment, &root->secondary);
709
710 root->mcfg_addr = acpi_pci_root_get_mcfg_addr(handle);
711
712 acpi_hid = acpi_device_hid(root->device);
713 if (strcmp(acpi_hid, "PNP0A08") == 0)
714 root->bridge_type = ACPI_BRIDGE_TYPE_PCIE;
715 else if (strcmp(acpi_hid, "ACPI0016") == 0)
716 root->bridge_type = ACPI_BRIDGE_TYPE_CXL;
717 else
718 dev_dbg(&device->dev, "Assuming non-PCIe host bridge\n");
719
720 negotiate_os_control(root, &no_aspm);
721
722 /*
723 * TBD: Need PCI interface for enumeration/configuration of roots.
724 */
725
726 /*
727 * Scan the Root Bridge
728 * --------------------
729 * Must do this prior to any attempt to bind the root device, as the
730 * PCI namespace does not get created until this call is made (and
731 * thus the root bridge's pci_dev does not exist).
732 */
733 root->bus = pci_acpi_scan_root(root);
734 if (!root->bus) {
735 dev_err(&device->dev,
736 "Bus %04x:%02x not present in PCI namespace\n",
737 root->segment, (unsigned int)root->secondary.start);
738 device->driver_data = NULL;
739 result = -ENODEV;
740 goto remove_dmar;
741 }
742
743 if (no_aspm)
744 pcie_no_aspm();
745
746 pci_acpi_add_bus_pm_notifier(device);
747 device_set_wakeup_capable(root->bus->bridge, device->wakeup.flags.valid);
748
749 if (hotadd) {
750 pcibios_resource_survey_bus(root->bus);
751 pci_assign_unassigned_root_bus_resources(root->bus);
752 /*
753 * This is only called for the hotadd case. For the boot-time
754 * case, we need to wait until after PCI initialization in
755 * order to deal with IOAPICs mapped in on a PCI BAR.
756 *
757 * This is currently x86-specific, because acpi_ioapic_add()
758 * is an empty function without CONFIG_ACPI_HOTPLUG_IOAPIC.
759 * And CONFIG_ACPI_HOTPLUG_IOAPIC depends on CONFIG_X86_IO_APIC
760 * (see drivers/acpi/Kconfig).
761 */
762 acpi_ioapic_add(root->device->handle);
763 }
764
765 pci_lock_rescan_remove();
766 pci_bus_add_devices(root->bus);
767 pci_unlock_rescan_remove();
768 return 1;
769
770remove_dmar:
771 if (hotadd)
772 dmar_device_remove(handle);
773end:
774 kfree(root);
775 return result;
776}
777
778static void acpi_pci_root_remove(struct acpi_device *device)
779{
780 struct acpi_pci_root *root = acpi_driver_data(device);
781
782 pci_lock_rescan_remove();
783
784 pci_stop_root_bus(root->bus);
785
786 pci_ioapic_remove(root);
787 device_set_wakeup_capable(root->bus->bridge, false);
788 pci_acpi_remove_bus_pm_notifier(device);
789
790 pci_remove_root_bus(root->bus);
791 WARN_ON(acpi_ioapic_remove(root));
792
793 dmar_device_remove(device->handle);
794
795 pci_unlock_rescan_remove();
796
797 kfree(root);
798}
799
800/*
801 * Following code to support acpi_pci_root_create() is copied from
802 * arch/x86/pci/acpi.c and modified so it could be reused by x86, IA64
803 * and ARM64.
804 */
805static void acpi_pci_root_validate_resources(struct device *dev,
806 struct list_head *resources,
807 unsigned long type)
808{
809 LIST_HEAD(list);
810 struct resource *res1, *res2, *root = NULL;
811 struct resource_entry *tmp, *entry, *entry2;
812
813 BUG_ON((type & (IORESOURCE_MEM | IORESOURCE_IO)) == 0);
814 root = (type & IORESOURCE_MEM) ? &iomem_resource : &ioport_resource;
815
816 list_splice_init(resources, &list);
817 resource_list_for_each_entry_safe(entry, tmp, &list) {
818 bool free = false;
819 resource_size_t end;
820
821 res1 = entry->res;
822 if (!(res1->flags & type))
823 goto next;
824
825 /* Exclude non-addressable range or non-addressable portion */
826 end = min(res1->end, root->end);
827 if (end <= res1->start) {
828 dev_info(dev, "host bridge window %pR (ignored, not CPU addressable)\n",
829 res1);
830 free = true;
831 goto next;
832 } else if (res1->end != end) {
833 dev_info(dev, "host bridge window %pR ([%#llx-%#llx] ignored, not CPU addressable)\n",
834 res1, (unsigned long long)end + 1,
835 (unsigned long long)res1->end);
836 res1->end = end;
837 }
838
839 resource_list_for_each_entry(entry2, resources) {
840 res2 = entry2->res;
841 if (!(res2->flags & type))
842 continue;
843
844 /*
845 * I don't like throwing away windows because then
846 * our resources no longer match the ACPI _CRS, but
847 * the kernel resource tree doesn't allow overlaps.
848 */
849 if (resource_union(res1, res2, res2)) {
850 dev_info(dev, "host bridge window expanded to %pR; %pR ignored\n",
851 res2, res1);
852 free = true;
853 goto next;
854 }
855 }
856
857next:
858 resource_list_del(entry);
859 if (free)
860 resource_list_free_entry(entry);
861 else
862 resource_list_add_tail(entry, resources);
863 }
864}
865
866static void acpi_pci_root_remap_iospace(struct fwnode_handle *fwnode,
867 struct resource_entry *entry)
868{
869#ifdef PCI_IOBASE
870 struct resource *res = entry->res;
871 resource_size_t cpu_addr = res->start;
872 resource_size_t pci_addr = cpu_addr - entry->offset;
873 resource_size_t length = resource_size(res);
874 unsigned long port;
875
876 if (pci_register_io_range(fwnode, cpu_addr, length))
877 goto err;
878
879 port = pci_address_to_pio(cpu_addr);
880 if (port == (unsigned long)-1)
881 goto err;
882
883 res->start = port;
884 res->end = port + length - 1;
885 entry->offset = port - pci_addr;
886
887 if (pci_remap_iospace(res, cpu_addr) < 0)
888 goto err;
889
890 pr_info("Remapped I/O %pa to %pR\n", &cpu_addr, res);
891 return;
892err:
893 res->flags |= IORESOURCE_DISABLED;
894#endif
895}
896
897int acpi_pci_probe_root_resources(struct acpi_pci_root_info *info)
898{
899 int ret;
900 struct list_head *list = &info->resources;
901 struct acpi_device *device = info->bridge;
902 struct resource_entry *entry, *tmp;
903 unsigned long flags;
904
905 flags = IORESOURCE_IO | IORESOURCE_MEM | IORESOURCE_MEM_8AND16BIT;
906 ret = acpi_dev_get_resources(device, list,
907 acpi_dev_filter_resource_type_cb,
908 (void *)flags);
909 if (ret < 0)
910 dev_warn(&device->dev,
911 "failed to parse _CRS method, error code %d\n", ret);
912 else if (ret == 0)
913 dev_dbg(&device->dev,
914 "no IO and memory resources present in _CRS\n");
915 else {
916 resource_list_for_each_entry_safe(entry, tmp, list) {
917 if (entry->res->flags & IORESOURCE_IO)
918 acpi_pci_root_remap_iospace(&device->fwnode,
919 entry);
920
921 if (entry->res->flags & IORESOURCE_DISABLED)
922 resource_list_destroy_entry(entry);
923 else
924 entry->res->name = info->name;
925 }
926 acpi_pci_root_validate_resources(&device->dev, list,
927 IORESOURCE_MEM);
928 acpi_pci_root_validate_resources(&device->dev, list,
929 IORESOURCE_IO);
930 }
931
932 return ret;
933}
934
935static void pci_acpi_root_add_resources(struct acpi_pci_root_info *info)
936{
937 struct resource_entry *entry, *tmp;
938 struct resource *res, *conflict, *root = NULL;
939
940 resource_list_for_each_entry_safe(entry, tmp, &info->resources) {
941 res = entry->res;
942 if (res->flags & IORESOURCE_MEM)
943 root = &iomem_resource;
944 else if (res->flags & IORESOURCE_IO)
945 root = &ioport_resource;
946 else
947 continue;
948
949 /*
950 * Some legacy x86 host bridge drivers use iomem_resource and
951 * ioport_resource as default resource pool, skip it.
952 */
953 if (res == root)
954 continue;
955
956 conflict = insert_resource_conflict(root, res);
957 if (conflict) {
958 dev_info(&info->bridge->dev,
959 "ignoring host bridge window %pR (conflicts with %s %pR)\n",
960 res, conflict->name, conflict);
961 resource_list_destroy_entry(entry);
962 }
963 }
964}
965
966static void __acpi_pci_root_release_info(struct acpi_pci_root_info *info)
967{
968 struct resource *res;
969 struct resource_entry *entry, *tmp;
970
971 if (!info)
972 return;
973
974 resource_list_for_each_entry_safe(entry, tmp, &info->resources) {
975 res = entry->res;
976 if (res->parent &&
977 (res->flags & (IORESOURCE_MEM | IORESOURCE_IO)))
978 release_resource(res);
979 resource_list_destroy_entry(entry);
980 }
981
982 info->ops->release_info(info);
983}
984
985static void acpi_pci_root_release_info(struct pci_host_bridge *bridge)
986{
987 struct resource *res;
988 struct resource_entry *entry;
989
990 resource_list_for_each_entry(entry, &bridge->windows) {
991 res = entry->res;
992 if (res->flags & IORESOURCE_IO)
993 pci_unmap_iospace(res);
994 if (res->parent &&
995 (res->flags & (IORESOURCE_MEM | IORESOURCE_IO)))
996 release_resource(res);
997 }
998 __acpi_pci_root_release_info(bridge->release_data);
999}
1000
1001struct pci_bus *acpi_pci_root_create(struct acpi_pci_root *root,
1002 struct acpi_pci_root_ops *ops,
1003 struct acpi_pci_root_info *info,
1004 void *sysdata)
1005{
1006 int ret, busnum = root->secondary.start;
1007 struct acpi_device *device = root->device;
1008 int node = acpi_get_node(device->handle);
1009 struct pci_bus *bus;
1010 struct pci_host_bridge *host_bridge;
1011 union acpi_object *obj;
1012
1013 info->root = root;
1014 info->bridge = device;
1015 info->ops = ops;
1016 INIT_LIST_HEAD(&info->resources);
1017 snprintf(info->name, sizeof(info->name), "PCI Bus %04x:%02x",
1018 root->segment, busnum);
1019
1020 if (ops->init_info && ops->init_info(info))
1021 goto out_release_info;
1022 if (ops->prepare_resources)
1023 ret = ops->prepare_resources(info);
1024 else
1025 ret = acpi_pci_probe_root_resources(info);
1026 if (ret < 0)
1027 goto out_release_info;
1028
1029 pci_acpi_root_add_resources(info);
1030 pci_add_resource(&info->resources, &root->secondary);
1031 bus = pci_create_root_bus(NULL, busnum, ops->pci_ops,
1032 sysdata, &info->resources);
1033 if (!bus)
1034 goto out_release_info;
1035
1036 host_bridge = to_pci_host_bridge(bus->bridge);
1037 if (!(root->osc_control_set & OSC_PCI_EXPRESS_NATIVE_HP_CONTROL))
1038 host_bridge->native_pcie_hotplug = 0;
1039 if (!(root->osc_control_set & OSC_PCI_SHPC_NATIVE_HP_CONTROL))
1040 host_bridge->native_shpc_hotplug = 0;
1041 if (!(root->osc_control_set & OSC_PCI_EXPRESS_AER_CONTROL))
1042 host_bridge->native_aer = 0;
1043 if (!(root->osc_control_set & OSC_PCI_EXPRESS_PME_CONTROL))
1044 host_bridge->native_pme = 0;
1045 if (!(root->osc_control_set & OSC_PCI_EXPRESS_LTR_CONTROL))
1046 host_bridge->native_ltr = 0;
1047 if (!(root->osc_control_set & OSC_PCI_EXPRESS_DPC_CONTROL))
1048 host_bridge->native_dpc = 0;
1049
1050 /*
1051 * Evaluate the "PCI Boot Configuration" _DSM Function. If it
1052 * exists and returns 0, we must preserve any PCI resource
1053 * assignments made by firmware for this host bridge.
1054 */
1055 obj = acpi_evaluate_dsm(ACPI_HANDLE(bus->bridge), &pci_acpi_dsm_guid, 1,
1056 DSM_PCI_PRESERVE_BOOT_CONFIG, NULL);
1057 if (obj && obj->type == ACPI_TYPE_INTEGER && obj->integer.value == 0)
1058 host_bridge->preserve_config = 1;
1059 ACPI_FREE(obj);
1060
1061 acpi_dev_power_up_children_with_adr(device);
1062
1063 pci_scan_child_bus(bus);
1064 pci_set_host_bridge_release(host_bridge, acpi_pci_root_release_info,
1065 info);
1066 if (node != NUMA_NO_NODE)
1067 dev_printk(KERN_DEBUG, &bus->dev, "on NUMA node %d\n", node);
1068 return bus;
1069
1070out_release_info:
1071 __acpi_pci_root_release_info(info);
1072 return NULL;
1073}
1074
1075void __init acpi_pci_root_init(void)
1076{
1077 if (acpi_pci_disabled)
1078 return;
1079
1080 pci_acpi_crs_quirks();
1081 acpi_scan_add_handler_with_hotplug(&pci_root_handler, "pci_root");
1082}