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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/*
2 * pci_root.c - ACPI PCI Root Bridge Driver ($Revision: 40 $)
3 *
4 * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
5 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
6 *
7 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or (at
12 * your option) any later version.
13 *
14 * This program is distributed in the hope that it will be useful, but
15 * WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * General Public License for more details.
18 *
19 * You should have received a copy of the GNU General Public License along
20 * with this program; if not, write to the Free Software Foundation, Inc.,
21 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
22 *
23 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
24 */
25
26#include <linux/kernel.h>
27#include <linux/module.h>
28#include <linux/init.h>
29#include <linux/types.h>
30#include <linux/mutex.h>
31#include <linux/pm.h>
32#include <linux/pm_runtime.h>
33#include <linux/pci.h>
34#include <linux/pci-acpi.h>
35#include <linux/pci-aspm.h>
36#include <linux/acpi.h>
37#include <linux/slab.h>
38#include <acpi/apei.h> /* for acpi_hest_init() */
39
40#include "internal.h"
41
42#define _COMPONENT ACPI_PCI_COMPONENT
43ACPI_MODULE_NAME("pci_root");
44#define ACPI_PCI_ROOT_CLASS "pci_bridge"
45#define ACPI_PCI_ROOT_DEVICE_NAME "PCI Root Bridge"
46static int acpi_pci_root_add(struct acpi_device *device,
47 const struct acpi_device_id *not_used);
48static void acpi_pci_root_remove(struct acpi_device *device);
49
50static int acpi_pci_root_scan_dependent(struct acpi_device *adev)
51{
52 acpiphp_check_host_bridge(adev);
53 return 0;
54}
55
56#define ACPI_PCIE_REQ_SUPPORT (OSC_PCI_EXT_CONFIG_SUPPORT \
57 | OSC_PCI_ASPM_SUPPORT \
58 | OSC_PCI_CLOCK_PM_SUPPORT \
59 | OSC_PCI_MSI_SUPPORT)
60
61static const struct acpi_device_id root_device_ids[] = {
62 {"PNP0A03", 0},
63 {"", 0},
64};
65
66static struct acpi_scan_handler pci_root_handler = {
67 .ids = root_device_ids,
68 .attach = acpi_pci_root_add,
69 .detach = acpi_pci_root_remove,
70 .hotplug = {
71 .enabled = true,
72 .scan_dependent = acpi_pci_root_scan_dependent,
73 },
74};
75
76static DEFINE_MUTEX(osc_lock);
77
78/**
79 * acpi_is_root_bridge - determine whether an ACPI CA node is a PCI root bridge
80 * @handle - the ACPI CA node in question.
81 *
82 * Note: we could make this API take a struct acpi_device * instead, but
83 * for now, it's more convenient to operate on an acpi_handle.
84 */
85int acpi_is_root_bridge(acpi_handle handle)
86{
87 int ret;
88 struct acpi_device *device;
89
90 ret = acpi_bus_get_device(handle, &device);
91 if (ret)
92 return 0;
93
94 ret = acpi_match_device_ids(device, root_device_ids);
95 if (ret)
96 return 0;
97 else
98 return 1;
99}
100EXPORT_SYMBOL_GPL(acpi_is_root_bridge);
101
102static acpi_status
103get_root_bridge_busnr_callback(struct acpi_resource *resource, void *data)
104{
105 struct resource *res = data;
106 struct acpi_resource_address64 address;
107 acpi_status status;
108
109 status = acpi_resource_to_address64(resource, &address);
110 if (ACPI_FAILURE(status))
111 return AE_OK;
112
113 if ((address.address_length > 0) &&
114 (address.resource_type == ACPI_BUS_NUMBER_RANGE)) {
115 res->start = address.minimum;
116 res->end = address.minimum + address.address_length - 1;
117 }
118
119 return AE_OK;
120}
121
122static acpi_status try_get_root_bridge_busnr(acpi_handle handle,
123 struct resource *res)
124{
125 acpi_status status;
126
127 res->start = -1;
128 status =
129 acpi_walk_resources(handle, METHOD_NAME__CRS,
130 get_root_bridge_busnr_callback, res);
131 if (ACPI_FAILURE(status))
132 return status;
133 if (res->start == -1)
134 return AE_ERROR;
135 return AE_OK;
136}
137
138struct pci_osc_bit_struct {
139 u32 bit;
140 char *desc;
141};
142
143static struct pci_osc_bit_struct pci_osc_support_bit[] = {
144 { OSC_PCI_EXT_CONFIG_SUPPORT, "ExtendedConfig" },
145 { OSC_PCI_ASPM_SUPPORT, "ASPM" },
146 { OSC_PCI_CLOCK_PM_SUPPORT, "ClockPM" },
147 { OSC_PCI_SEGMENT_GROUPS_SUPPORT, "Segments" },
148 { OSC_PCI_MSI_SUPPORT, "MSI" },
149};
150
151static struct pci_osc_bit_struct pci_osc_control_bit[] = {
152 { OSC_PCI_EXPRESS_NATIVE_HP_CONTROL, "PCIeHotplug" },
153 { OSC_PCI_SHPC_NATIVE_HP_CONTROL, "SHPCHotplug" },
154 { OSC_PCI_EXPRESS_PME_CONTROL, "PME" },
155 { OSC_PCI_EXPRESS_AER_CONTROL, "AER" },
156 { OSC_PCI_EXPRESS_CAPABILITY_CONTROL, "PCIeCapability" },
157};
158
159static void decode_osc_bits(struct acpi_pci_root *root, char *msg, u32 word,
160 struct pci_osc_bit_struct *table, int size)
161{
162 char buf[80];
163 int i, len = 0;
164 struct pci_osc_bit_struct *entry;
165
166 buf[0] = '\0';
167 for (i = 0, entry = table; i < size; i++, entry++)
168 if (word & entry->bit)
169 len += snprintf(buf + len, sizeof(buf) - len, "%s%s",
170 len ? " " : "", entry->desc);
171
172 dev_info(&root->device->dev, "_OSC: %s [%s]\n", msg, buf);
173}
174
175static void decode_osc_support(struct acpi_pci_root *root, char *msg, u32 word)
176{
177 decode_osc_bits(root, msg, word, pci_osc_support_bit,
178 ARRAY_SIZE(pci_osc_support_bit));
179}
180
181static void decode_osc_control(struct acpi_pci_root *root, char *msg, u32 word)
182{
183 decode_osc_bits(root, msg, word, pci_osc_control_bit,
184 ARRAY_SIZE(pci_osc_control_bit));
185}
186
187static u8 pci_osc_uuid_str[] = "33DB4D5B-1FF7-401C-9657-7441C03DD766";
188
189static acpi_status acpi_pci_run_osc(acpi_handle handle,
190 const u32 *capbuf, u32 *retval)
191{
192 struct acpi_osc_context context = {
193 .uuid_str = pci_osc_uuid_str,
194 .rev = 1,
195 .cap.length = 12,
196 .cap.pointer = (void *)capbuf,
197 };
198 acpi_status status;
199
200 status = acpi_run_osc(handle, &context);
201 if (ACPI_SUCCESS(status)) {
202 *retval = *((u32 *)(context.ret.pointer + 8));
203 kfree(context.ret.pointer);
204 }
205 return status;
206}
207
208static acpi_status acpi_pci_query_osc(struct acpi_pci_root *root,
209 u32 support,
210 u32 *control)
211{
212 acpi_status status;
213 u32 result, capbuf[3];
214
215 support &= OSC_PCI_SUPPORT_MASKS;
216 support |= root->osc_support_set;
217
218 capbuf[OSC_QUERY_DWORD] = OSC_QUERY_ENABLE;
219 capbuf[OSC_SUPPORT_DWORD] = support;
220 if (control) {
221 *control &= OSC_PCI_CONTROL_MASKS;
222 capbuf[OSC_CONTROL_DWORD] = *control | root->osc_control_set;
223 } else {
224 /* Run _OSC query only with existing controls. */
225 capbuf[OSC_CONTROL_DWORD] = root->osc_control_set;
226 }
227
228 status = acpi_pci_run_osc(root->device->handle, capbuf, &result);
229 if (ACPI_SUCCESS(status)) {
230 root->osc_support_set = support;
231 if (control)
232 *control = result;
233 }
234 return status;
235}
236
237static acpi_status acpi_pci_osc_support(struct acpi_pci_root *root, u32 flags)
238{
239 acpi_status status;
240
241 mutex_lock(&osc_lock);
242 status = acpi_pci_query_osc(root, flags, NULL);
243 mutex_unlock(&osc_lock);
244 return status;
245}
246
247struct acpi_pci_root *acpi_pci_find_root(acpi_handle handle)
248{
249 struct acpi_pci_root *root;
250 struct acpi_device *device;
251
252 if (acpi_bus_get_device(handle, &device) ||
253 acpi_match_device_ids(device, root_device_ids))
254 return NULL;
255
256 root = acpi_driver_data(device);
257
258 return root;
259}
260EXPORT_SYMBOL_GPL(acpi_pci_find_root);
261
262struct acpi_handle_node {
263 struct list_head node;
264 acpi_handle handle;
265};
266
267/**
268 * acpi_get_pci_dev - convert ACPI CA handle to struct pci_dev
269 * @handle: the handle in question
270 *
271 * Given an ACPI CA handle, the desired PCI device is located in the
272 * list of PCI devices.
273 *
274 * If the device is found, its reference count is increased and this
275 * function returns a pointer to its data structure. The caller must
276 * decrement the reference count by calling pci_dev_put().
277 * If no device is found, %NULL is returned.
278 */
279struct pci_dev *acpi_get_pci_dev(acpi_handle handle)
280{
281 int dev, fn;
282 unsigned long long adr;
283 acpi_status status;
284 acpi_handle phandle;
285 struct pci_bus *pbus;
286 struct pci_dev *pdev = NULL;
287 struct acpi_handle_node *node, *tmp;
288 struct acpi_pci_root *root;
289 LIST_HEAD(device_list);
290
291 /*
292 * Walk up the ACPI CA namespace until we reach a PCI root bridge.
293 */
294 phandle = handle;
295 while (!acpi_is_root_bridge(phandle)) {
296 node = kzalloc(sizeof(struct acpi_handle_node), GFP_KERNEL);
297 if (!node)
298 goto out;
299
300 INIT_LIST_HEAD(&node->node);
301 node->handle = phandle;
302 list_add(&node->node, &device_list);
303
304 status = acpi_get_parent(phandle, &phandle);
305 if (ACPI_FAILURE(status))
306 goto out;
307 }
308
309 root = acpi_pci_find_root(phandle);
310 if (!root)
311 goto out;
312
313 pbus = root->bus;
314
315 /*
316 * Now, walk back down the PCI device tree until we return to our
317 * original handle. Assumes that everything between the PCI root
318 * bridge and the device we're looking for must be a P2P bridge.
319 */
320 list_for_each_entry(node, &device_list, node) {
321 acpi_handle hnd = node->handle;
322 status = acpi_evaluate_integer(hnd, "_ADR", NULL, &adr);
323 if (ACPI_FAILURE(status))
324 goto out;
325 dev = (adr >> 16) & 0xffff;
326 fn = adr & 0xffff;
327
328 pdev = pci_get_slot(pbus, PCI_DEVFN(dev, fn));
329 if (!pdev || hnd == handle)
330 break;
331
332 pbus = pdev->subordinate;
333 pci_dev_put(pdev);
334
335 /*
336 * This function may be called for a non-PCI device that has a
337 * PCI parent (eg. a disk under a PCI SATA controller). In that
338 * case pdev->subordinate will be NULL for the parent.
339 */
340 if (!pbus) {
341 dev_dbg(&pdev->dev, "Not a PCI-to-PCI bridge\n");
342 pdev = NULL;
343 break;
344 }
345 }
346out:
347 list_for_each_entry_safe(node, tmp, &device_list, node)
348 kfree(node);
349
350 return pdev;
351}
352EXPORT_SYMBOL_GPL(acpi_get_pci_dev);
353
354/**
355 * acpi_pci_osc_control_set - Request control of PCI root _OSC features.
356 * @handle: ACPI handle of a PCI root bridge (or PCIe Root Complex).
357 * @mask: Mask of _OSC bits to request control of, place to store control mask.
358 * @req: Mask of _OSC bits the control of is essential to the caller.
359 *
360 * Run _OSC query for @mask and if that is successful, compare the returned
361 * mask of control bits with @req. If all of the @req bits are set in the
362 * returned mask, run _OSC request for it.
363 *
364 * The variable at the @mask address may be modified regardless of whether or
365 * not the function returns success. On success it will contain the mask of
366 * _OSC bits the BIOS has granted control of, but its contents are meaningless
367 * on failure.
368 **/
369acpi_status acpi_pci_osc_control_set(acpi_handle handle, u32 *mask, u32 req)
370{
371 struct acpi_pci_root *root;
372 acpi_status status = AE_OK;
373 u32 ctrl, capbuf[3];
374
375 if (!mask)
376 return AE_BAD_PARAMETER;
377
378 ctrl = *mask & OSC_PCI_CONTROL_MASKS;
379 if ((ctrl & req) != req)
380 return AE_TYPE;
381
382 root = acpi_pci_find_root(handle);
383 if (!root)
384 return AE_NOT_EXIST;
385
386 mutex_lock(&osc_lock);
387
388 *mask = ctrl | root->osc_control_set;
389 /* No need to evaluate _OSC if the control was already granted. */
390 if ((root->osc_control_set & ctrl) == ctrl)
391 goto out;
392
393 /* Need to check the available controls bits before requesting them. */
394 while (*mask) {
395 status = acpi_pci_query_osc(root, root->osc_support_set, mask);
396 if (ACPI_FAILURE(status))
397 goto out;
398 if (ctrl == *mask)
399 break;
400 decode_osc_control(root, "platform does not support",
401 ctrl & ~(*mask));
402 ctrl = *mask;
403 }
404
405 if ((ctrl & req) != req) {
406 decode_osc_control(root, "not requesting control; platform does not support",
407 req & ~(ctrl));
408 status = AE_SUPPORT;
409 goto out;
410 }
411
412 capbuf[OSC_QUERY_DWORD] = 0;
413 capbuf[OSC_SUPPORT_DWORD] = root->osc_support_set;
414 capbuf[OSC_CONTROL_DWORD] = ctrl;
415 status = acpi_pci_run_osc(handle, capbuf, mask);
416 if (ACPI_SUCCESS(status))
417 root->osc_control_set = *mask;
418out:
419 mutex_unlock(&osc_lock);
420 return status;
421}
422EXPORT_SYMBOL(acpi_pci_osc_control_set);
423
424static void negotiate_os_control(struct acpi_pci_root *root, int *no_aspm,
425 int *clear_aspm)
426{
427 u32 support, control, requested;
428 acpi_status status;
429 struct acpi_device *device = root->device;
430 acpi_handle handle = device->handle;
431
432 /*
433 * All supported architectures that use ACPI have support for
434 * PCI domains, so we indicate this in _OSC support capabilities.
435 */
436 support = OSC_PCI_SEGMENT_GROUPS_SUPPORT;
437 if (pci_ext_cfg_avail())
438 support |= OSC_PCI_EXT_CONFIG_SUPPORT;
439 if (pcie_aspm_support_enabled())
440 support |= OSC_PCI_ASPM_SUPPORT | OSC_PCI_CLOCK_PM_SUPPORT;
441 if (pci_msi_enabled())
442 support |= OSC_PCI_MSI_SUPPORT;
443
444 decode_osc_support(root, "OS supports", support);
445 status = acpi_pci_osc_support(root, support);
446 if (ACPI_FAILURE(status)) {
447 dev_info(&device->dev, "_OSC failed (%s); disabling ASPM\n",
448 acpi_format_exception(status));
449 *no_aspm = 1;
450 return;
451 }
452
453 if (pcie_ports_disabled) {
454 dev_info(&device->dev, "PCIe port services disabled; not requesting _OSC control\n");
455 return;
456 }
457
458 if ((support & ACPI_PCIE_REQ_SUPPORT) != ACPI_PCIE_REQ_SUPPORT) {
459 decode_osc_support(root, "not requesting OS control; OS requires",
460 ACPI_PCIE_REQ_SUPPORT);
461 return;
462 }
463
464 control = OSC_PCI_EXPRESS_CAPABILITY_CONTROL
465 | OSC_PCI_EXPRESS_NATIVE_HP_CONTROL
466 | OSC_PCI_EXPRESS_PME_CONTROL;
467
468 if (pci_aer_available()) {
469 if (aer_acpi_firmware_first())
470 dev_info(&device->dev,
471 "PCIe AER handled by firmware\n");
472 else
473 control |= OSC_PCI_EXPRESS_AER_CONTROL;
474 }
475
476 requested = control;
477 status = acpi_pci_osc_control_set(handle, &control,
478 OSC_PCI_EXPRESS_CAPABILITY_CONTROL);
479 if (ACPI_SUCCESS(status)) {
480 decode_osc_control(root, "OS now controls", control);
481 if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_ASPM) {
482 /*
483 * We have ASPM control, but the FADT indicates
484 * that it's unsupported. Clear it.
485 */
486 *clear_aspm = 1;
487 }
488 } else {
489 decode_osc_control(root, "OS requested", requested);
490 decode_osc_control(root, "platform willing to grant", control);
491 dev_info(&device->dev, "_OSC failed (%s); disabling ASPM\n",
492 acpi_format_exception(status));
493
494 /*
495 * We want to disable ASPM here, but aspm_disabled
496 * needs to remain in its state from boot so that we
497 * properly handle PCIe 1.1 devices. So we set this
498 * flag here, to defer the action until after the ACPI
499 * root scan.
500 */
501 *no_aspm = 1;
502 }
503}
504
505static int acpi_pci_root_add(struct acpi_device *device,
506 const struct acpi_device_id *not_used)
507{
508 unsigned long long segment, bus;
509 acpi_status status;
510 int result;
511 struct acpi_pci_root *root;
512 acpi_handle handle = device->handle;
513 int no_aspm = 0, clear_aspm = 0;
514
515 root = kzalloc(sizeof(struct acpi_pci_root), GFP_KERNEL);
516 if (!root)
517 return -ENOMEM;
518
519 segment = 0;
520 status = acpi_evaluate_integer(handle, METHOD_NAME__SEG, NULL,
521 &segment);
522 if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
523 dev_err(&device->dev, "can't evaluate _SEG\n");
524 result = -ENODEV;
525 goto end;
526 }
527
528 /* Check _CRS first, then _BBN. If no _BBN, default to zero. */
529 root->secondary.flags = IORESOURCE_BUS;
530 status = try_get_root_bridge_busnr(handle, &root->secondary);
531 if (ACPI_FAILURE(status)) {
532 /*
533 * We need both the start and end of the downstream bus range
534 * to interpret _CBA (MMCONFIG base address), so it really is
535 * supposed to be in _CRS. If we don't find it there, all we
536 * can do is assume [_BBN-0xFF] or [0-0xFF].
537 */
538 root->secondary.end = 0xFF;
539 dev_warn(&device->dev,
540 FW_BUG "no secondary bus range in _CRS\n");
541 status = acpi_evaluate_integer(handle, METHOD_NAME__BBN,
542 NULL, &bus);
543 if (ACPI_SUCCESS(status))
544 root->secondary.start = bus;
545 else if (status == AE_NOT_FOUND)
546 root->secondary.start = 0;
547 else {
548 dev_err(&device->dev, "can't evaluate _BBN\n");
549 result = -ENODEV;
550 goto end;
551 }
552 }
553
554 root->device = device;
555 root->segment = segment & 0xFFFF;
556 strcpy(acpi_device_name(device), ACPI_PCI_ROOT_DEVICE_NAME);
557 strcpy(acpi_device_class(device), ACPI_PCI_ROOT_CLASS);
558 device->driver_data = root;
559
560 pr_info(PREFIX "%s [%s] (domain %04x %pR)\n",
561 acpi_device_name(device), acpi_device_bid(device),
562 root->segment, &root->secondary);
563
564 root->mcfg_addr = acpi_pci_root_get_mcfg_addr(handle);
565
566 negotiate_os_control(root, &no_aspm, &clear_aspm);
567
568 /*
569 * TBD: Need PCI interface for enumeration/configuration of roots.
570 */
571
572 /*
573 * Scan the Root Bridge
574 * --------------------
575 * Must do this prior to any attempt to bind the root device, as the
576 * PCI namespace does not get created until this call is made (and
577 * thus the root bridge's pci_dev does not exist).
578 */
579 root->bus = pci_acpi_scan_root(root);
580 if (!root->bus) {
581 dev_err(&device->dev,
582 "Bus %04x:%02x not present in PCI namespace\n",
583 root->segment, (unsigned int)root->secondary.start);
584 device->driver_data = NULL;
585 result = -ENODEV;
586 goto end;
587 }
588
589 if (clear_aspm) {
590 dev_info(&device->dev, "Disabling ASPM (FADT indicates it is unsupported)\n");
591 pcie_clear_aspm(root->bus);
592 }
593 if (no_aspm)
594 pcie_no_aspm();
595
596 pci_acpi_add_bus_pm_notifier(device, root->bus);
597 if (device->wakeup.flags.run_wake)
598 device_set_run_wake(root->bus->bridge, true);
599
600 if (system_state != SYSTEM_BOOTING) {
601 pcibios_resource_survey_bus(root->bus);
602 pci_assign_unassigned_root_bus_resources(root->bus);
603 }
604
605 pci_lock_rescan_remove();
606 pci_bus_add_devices(root->bus);
607 pci_unlock_rescan_remove();
608 return 1;
609
610end:
611 kfree(root);
612 return result;
613}
614
615static void acpi_pci_root_remove(struct acpi_device *device)
616{
617 struct acpi_pci_root *root = acpi_driver_data(device);
618
619 pci_lock_rescan_remove();
620
621 pci_stop_root_bus(root->bus);
622
623 device_set_run_wake(root->bus->bridge, false);
624 pci_acpi_remove_bus_pm_notifier(device);
625
626 pci_remove_root_bus(root->bus);
627
628 pci_unlock_rescan_remove();
629
630 kfree(root);
631}
632
633void __init acpi_pci_root_init(void)
634{
635 acpi_hest_init();
636 if (acpi_pci_disabled)
637 return;
638
639 pci_acpi_crs_quirks();
640 acpi_scan_add_handler_with_hotplug(&pci_root_handler, "pci_root");
641}