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v5.9
  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}
v5.4
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 *  pci_root.c - ACPI PCI Root Bridge Driver ($Revision: 40 $)
  4 *
  5 *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
  6 *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
  7 */
  8
  9#include <linux/kernel.h>
 10#include <linux/module.h>
 11#include <linux/init.h>
 12#include <linux/types.h>
 13#include <linux/mutex.h>
 14#include <linux/pm.h>
 15#include <linux/pm_runtime.h>
 16#include <linux/pci.h>
 17#include <linux/pci-acpi.h>
 18#include <linux/dmar.h>
 19#include <linux/acpi.h>
 20#include <linux/slab.h>
 21#include <linux/dmi.h>
 22#include <linux/platform_data/x86/apple.h>
 23#include <acpi/apei.h>	/* for acpi_hest_init() */
 24
 25#include "internal.h"
 26
 27#define _COMPONENT		ACPI_PCI_COMPONENT
 28ACPI_MODULE_NAME("pci_root");
 29#define ACPI_PCI_ROOT_CLASS		"pci_bridge"
 30#define ACPI_PCI_ROOT_DEVICE_NAME	"PCI Root Bridge"
 31static int acpi_pci_root_add(struct acpi_device *device,
 32			     const struct acpi_device_id *not_used);
 33static void acpi_pci_root_remove(struct acpi_device *device);
 34
 35static int acpi_pci_root_scan_dependent(struct acpi_device *adev)
 36{
 37	acpiphp_check_host_bridge(adev);
 38	return 0;
 39}
 40
 41#define ACPI_PCIE_REQ_SUPPORT (OSC_PCI_EXT_CONFIG_SUPPORT \
 42				| OSC_PCI_ASPM_SUPPORT \
 43				| OSC_PCI_CLOCK_PM_SUPPORT \
 44				| OSC_PCI_MSI_SUPPORT)
 45
 46static const struct acpi_device_id root_device_ids[] = {
 47	{"PNP0A03", 0},
 48	{"", 0},
 49};
 50
 51static struct acpi_scan_handler pci_root_handler = {
 52	.ids = root_device_ids,
 53	.attach = acpi_pci_root_add,
 54	.detach = acpi_pci_root_remove,
 55	.hotplug = {
 56		.enabled = true,
 57		.scan_dependent = acpi_pci_root_scan_dependent,
 58	},
 59};
 60
 61static DEFINE_MUTEX(osc_lock);
 62
 63/**
 64 * acpi_is_root_bridge - determine whether an ACPI CA node is a PCI root bridge
 65 * @handle - the ACPI CA node in question.
 66 *
 67 * Note: we could make this API take a struct acpi_device * instead, but
 68 * for now, it's more convenient to operate on an acpi_handle.
 69 */
 70int acpi_is_root_bridge(acpi_handle handle)
 71{
 72	int ret;
 73	struct acpi_device *device;
 74
 75	ret = acpi_bus_get_device(handle, &device);
 76	if (ret)
 77		return 0;
 78
 79	ret = acpi_match_device_ids(device, root_device_ids);
 80	if (ret)
 81		return 0;
 82	else
 83		return 1;
 84}
 85EXPORT_SYMBOL_GPL(acpi_is_root_bridge);
 86
 87static acpi_status
 88get_root_bridge_busnr_callback(struct acpi_resource *resource, void *data)
 89{
 90	struct resource *res = data;
 91	struct acpi_resource_address64 address;
 92	acpi_status status;
 93
 94	status = acpi_resource_to_address64(resource, &address);
 95	if (ACPI_FAILURE(status))
 96		return AE_OK;
 97
 98	if ((address.address.address_length > 0) &&
 99	    (address.resource_type == ACPI_BUS_NUMBER_RANGE)) {
100		res->start = address.address.minimum;
101		res->end = address.address.minimum + address.address.address_length - 1;
102	}
103
104	return AE_OK;
105}
106
107static acpi_status try_get_root_bridge_busnr(acpi_handle handle,
108					     struct resource *res)
109{
110	acpi_status status;
111
112	res->start = -1;
113	status =
114	    acpi_walk_resources(handle, METHOD_NAME__CRS,
115				get_root_bridge_busnr_callback, res);
116	if (ACPI_FAILURE(status))
117		return status;
118	if (res->start == -1)
119		return AE_ERROR;
120	return AE_OK;
121}
122
123struct pci_osc_bit_struct {
124	u32 bit;
125	char *desc;
126};
127
128static struct pci_osc_bit_struct pci_osc_support_bit[] = {
129	{ OSC_PCI_EXT_CONFIG_SUPPORT, "ExtendedConfig" },
130	{ OSC_PCI_ASPM_SUPPORT, "ASPM" },
131	{ OSC_PCI_CLOCK_PM_SUPPORT, "ClockPM" },
132	{ OSC_PCI_SEGMENT_GROUPS_SUPPORT, "Segments" },
133	{ OSC_PCI_MSI_SUPPORT, "MSI" },
 
134	{ OSC_PCI_HPX_TYPE_3_SUPPORT, "HPX-Type3" },
135};
136
137static struct pci_osc_bit_struct pci_osc_control_bit[] = {
138	{ OSC_PCI_EXPRESS_NATIVE_HP_CONTROL, "PCIeHotplug" },
139	{ OSC_PCI_SHPC_NATIVE_HP_CONTROL, "SHPCHotplug" },
140	{ OSC_PCI_EXPRESS_PME_CONTROL, "PME" },
141	{ OSC_PCI_EXPRESS_AER_CONTROL, "AER" },
142	{ OSC_PCI_EXPRESS_CAPABILITY_CONTROL, "PCIeCapability" },
143	{ OSC_PCI_EXPRESS_LTR_CONTROL, "LTR" },
 
144};
145
146static void decode_osc_bits(struct acpi_pci_root *root, char *msg, u32 word,
147			    struct pci_osc_bit_struct *table, int size)
148{
149	char buf[80];
150	int i, len = 0;
151	struct pci_osc_bit_struct *entry;
152
153	buf[0] = '\0';
154	for (i = 0, entry = table; i < size; i++, entry++)
155		if (word & entry->bit)
156			len += snprintf(buf + len, sizeof(buf) - len, "%s%s",
157					len ? " " : "", entry->desc);
158
159	dev_info(&root->device->dev, "_OSC: %s [%s]\n", msg, buf);
160}
161
162static void decode_osc_support(struct acpi_pci_root *root, char *msg, u32 word)
163{
164	decode_osc_bits(root, msg, word, pci_osc_support_bit,
165			ARRAY_SIZE(pci_osc_support_bit));
166}
167
168static void decode_osc_control(struct acpi_pci_root *root, char *msg, u32 word)
169{
170	decode_osc_bits(root, msg, word, pci_osc_control_bit,
171			ARRAY_SIZE(pci_osc_control_bit));
172}
173
174static u8 pci_osc_uuid_str[] = "33DB4D5B-1FF7-401C-9657-7441C03DD766";
175
176static acpi_status acpi_pci_run_osc(acpi_handle handle,
177				    const u32 *capbuf, u32 *retval)
178{
179	struct acpi_osc_context context = {
180		.uuid_str = pci_osc_uuid_str,
181		.rev = 1,
182		.cap.length = 12,
183		.cap.pointer = (void *)capbuf,
184	};
185	acpi_status status;
186
187	status = acpi_run_osc(handle, &context);
188	if (ACPI_SUCCESS(status)) {
189		*retval = *((u32 *)(context.ret.pointer + 8));
190		kfree(context.ret.pointer);
191	}
192	return status;
193}
194
195static acpi_status acpi_pci_query_osc(struct acpi_pci_root *root,
196					u32 support,
197					u32 *control)
198{
199	acpi_status status;
200	u32 result, capbuf[3];
201
202	support &= OSC_PCI_SUPPORT_MASKS;
203	support |= root->osc_support_set;
204
205	capbuf[OSC_QUERY_DWORD] = OSC_QUERY_ENABLE;
206	capbuf[OSC_SUPPORT_DWORD] = support;
207	if (control) {
208		*control &= OSC_PCI_CONTROL_MASKS;
209		capbuf[OSC_CONTROL_DWORD] = *control | root->osc_control_set;
210	} else {
211		/* Run _OSC query only with existing controls. */
212		capbuf[OSC_CONTROL_DWORD] = root->osc_control_set;
213	}
214
215	status = acpi_pci_run_osc(root->device->handle, capbuf, &result);
216	if (ACPI_SUCCESS(status)) {
217		root->osc_support_set = support;
218		if (control)
219			*control = result;
220	}
221	return status;
222}
223
224static acpi_status acpi_pci_osc_support(struct acpi_pci_root *root, u32 flags)
225{
226	acpi_status status;
227
228	mutex_lock(&osc_lock);
229	status = acpi_pci_query_osc(root, flags, NULL);
230	mutex_unlock(&osc_lock);
231	return status;
232}
233
234struct acpi_pci_root *acpi_pci_find_root(acpi_handle handle)
235{
236	struct acpi_pci_root *root;
237	struct acpi_device *device;
238
239	if (acpi_bus_get_device(handle, &device) ||
240	    acpi_match_device_ids(device, root_device_ids))
241		return NULL;
242
243	root = acpi_driver_data(device);
244
245	return root;
246}
247EXPORT_SYMBOL_GPL(acpi_pci_find_root);
248
249struct acpi_handle_node {
250	struct list_head node;
251	acpi_handle handle;
252};
253
254/**
255 * acpi_get_pci_dev - convert ACPI CA handle to struct pci_dev
256 * @handle: the handle in question
257 *
258 * Given an ACPI CA handle, the desired PCI device is located in the
259 * list of PCI devices.
260 *
261 * If the device is found, its reference count is increased and this
262 * function returns a pointer to its data structure.  The caller must
263 * decrement the reference count by calling pci_dev_put().
264 * If no device is found, %NULL is returned.
265 */
266struct pci_dev *acpi_get_pci_dev(acpi_handle handle)
267{
268	int dev, fn;
269	unsigned long long adr;
270	acpi_status status;
271	acpi_handle phandle;
272	struct pci_bus *pbus;
273	struct pci_dev *pdev = NULL;
274	struct acpi_handle_node *node, *tmp;
275	struct acpi_pci_root *root;
276	LIST_HEAD(device_list);
277
278	/*
279	 * Walk up the ACPI CA namespace until we reach a PCI root bridge.
280	 */
281	phandle = handle;
282	while (!acpi_is_root_bridge(phandle)) {
283		node = kzalloc(sizeof(struct acpi_handle_node), GFP_KERNEL);
284		if (!node)
285			goto out;
286
287		INIT_LIST_HEAD(&node->node);
288		node->handle = phandle;
289		list_add(&node->node, &device_list);
290
291		status = acpi_get_parent(phandle, &phandle);
292		if (ACPI_FAILURE(status))
293			goto out;
294	}
295
296	root = acpi_pci_find_root(phandle);
297	if (!root)
298		goto out;
299
300	pbus = root->bus;
301
302	/*
303	 * Now, walk back down the PCI device tree until we return to our
304	 * original handle. Assumes that everything between the PCI root
305	 * bridge and the device we're looking for must be a P2P bridge.
306	 */
307	list_for_each_entry(node, &device_list, node) {
308		acpi_handle hnd = node->handle;
309		status = acpi_evaluate_integer(hnd, "_ADR", NULL, &adr);
310		if (ACPI_FAILURE(status))
311			goto out;
312		dev = (adr >> 16) & 0xffff;
313		fn  = adr & 0xffff;
314
315		pdev = pci_get_slot(pbus, PCI_DEVFN(dev, fn));
316		if (!pdev || hnd == handle)
317			break;
318
319		pbus = pdev->subordinate;
320		pci_dev_put(pdev);
321
322		/*
323		 * This function may be called for a non-PCI device that has a
324		 * PCI parent (eg. a disk under a PCI SATA controller).  In that
325		 * case pdev->subordinate will be NULL for the parent.
326		 */
327		if (!pbus) {
328			dev_dbg(&pdev->dev, "Not a PCI-to-PCI bridge\n");
329			pdev = NULL;
330			break;
331		}
332	}
333out:
334	list_for_each_entry_safe(node, tmp, &device_list, node)
335		kfree(node);
336
337	return pdev;
338}
339EXPORT_SYMBOL_GPL(acpi_get_pci_dev);
340
341/**
342 * acpi_pci_osc_control_set - Request control of PCI root _OSC features.
343 * @handle: ACPI handle of a PCI root bridge (or PCIe Root Complex).
344 * @mask: Mask of _OSC bits to request control of, place to store control mask.
345 * @req: Mask of _OSC bits the control of is essential to the caller.
346 *
347 * Run _OSC query for @mask and if that is successful, compare the returned
348 * mask of control bits with @req.  If all of the @req bits are set in the
349 * returned mask, run _OSC request for it.
350 *
351 * The variable at the @mask address may be modified regardless of whether or
352 * not the function returns success.  On success it will contain the mask of
353 * _OSC bits the BIOS has granted control of, but its contents are meaningless
354 * on failure.
355 **/
356acpi_status acpi_pci_osc_control_set(acpi_handle handle, u32 *mask, u32 req)
357{
358	struct acpi_pci_root *root;
359	acpi_status status = AE_OK;
360	u32 ctrl, capbuf[3];
361
362	if (!mask)
363		return AE_BAD_PARAMETER;
364
365	ctrl = *mask & OSC_PCI_CONTROL_MASKS;
366	if ((ctrl & req) != req)
367		return AE_TYPE;
368
369	root = acpi_pci_find_root(handle);
370	if (!root)
371		return AE_NOT_EXIST;
372
373	mutex_lock(&osc_lock);
374
375	*mask = ctrl | root->osc_control_set;
376	/* No need to evaluate _OSC if the control was already granted. */
377	if ((root->osc_control_set & ctrl) == ctrl)
378		goto out;
379
380	/* Need to check the available controls bits before requesting them. */
381	while (*mask) {
382		status = acpi_pci_query_osc(root, root->osc_support_set, mask);
383		if (ACPI_FAILURE(status))
384			goto out;
385		if (ctrl == *mask)
386			break;
387		decode_osc_control(root, "platform does not support",
388				   ctrl & ~(*mask));
389		ctrl = *mask;
390	}
391
392	if ((ctrl & req) != req) {
393		decode_osc_control(root, "not requesting control; platform does not support",
394				   req & ~(ctrl));
395		status = AE_SUPPORT;
396		goto out;
397	}
398
399	capbuf[OSC_QUERY_DWORD] = 0;
400	capbuf[OSC_SUPPORT_DWORD] = root->osc_support_set;
401	capbuf[OSC_CONTROL_DWORD] = ctrl;
402	status = acpi_pci_run_osc(handle, capbuf, mask);
403	if (ACPI_SUCCESS(status))
404		root->osc_control_set = *mask;
405out:
406	mutex_unlock(&osc_lock);
407	return status;
408}
409EXPORT_SYMBOL(acpi_pci_osc_control_set);
410
411static void negotiate_os_control(struct acpi_pci_root *root, int *no_aspm,
412				 bool is_pcie)
413{
414	u32 support, control, requested;
415	acpi_status status;
416	struct acpi_device *device = root->device;
417	acpi_handle handle = device->handle;
418
419	/*
420	 * Apple always return failure on _OSC calls when _OSI("Darwin") has
421	 * been called successfully. We know the feature set supported by the
422	 * platform, so avoid calling _OSC at all
423	 */
424	if (x86_apple_machine) {
425		root->osc_control_set = ~OSC_PCI_EXPRESS_PME_CONTROL;
426		decode_osc_control(root, "OS assumes control of",
427				   root->osc_control_set);
428		return;
429	}
430
431	/*
432	 * All supported architectures that use ACPI have support for
433	 * PCI domains, so we indicate this in _OSC support capabilities.
434	 */
435	support = OSC_PCI_SEGMENT_GROUPS_SUPPORT;
436	support |= OSC_PCI_HPX_TYPE_3_SUPPORT;
437	if (pci_ext_cfg_avail())
438		support |= OSC_PCI_EXT_CONFIG_SUPPORT;
439	if (pcie_aspm_support_enabled())
440		support |= OSC_PCI_ASPM_SUPPORT | OSC_PCI_CLOCK_PM_SUPPORT;
441	if (pci_msi_enabled())
442		support |= OSC_PCI_MSI_SUPPORT;
 
 
443
444	decode_osc_support(root, "OS supports", support);
445	status = acpi_pci_osc_support(root, support);
446	if (ACPI_FAILURE(status)) {
447		*no_aspm = 1;
448
449		/* _OSC is optional for PCI host bridges */
450		if ((status == AE_NOT_FOUND) && !is_pcie)
451			return;
452
453		dev_info(&device->dev, "_OSC failed (%s)%s\n",
454			 acpi_format_exception(status),
455			 pcie_aspm_support_enabled() ? "; disabling ASPM" : "");
456		return;
457	}
458
459	if (pcie_ports_disabled) {
460		dev_info(&device->dev, "PCIe port services disabled; not requesting _OSC control\n");
461		return;
462	}
463
464	if ((support & ACPI_PCIE_REQ_SUPPORT) != ACPI_PCIE_REQ_SUPPORT) {
465		decode_osc_support(root, "not requesting OS control; OS requires",
466				   ACPI_PCIE_REQ_SUPPORT);
467		return;
468	}
469
470	control = OSC_PCI_EXPRESS_CAPABILITY_CONTROL
471		| OSC_PCI_EXPRESS_PME_CONTROL;
472
473	if (IS_ENABLED(CONFIG_PCIEASPM))
474		control |= OSC_PCI_EXPRESS_LTR_CONTROL;
475
476	if (IS_ENABLED(CONFIG_HOTPLUG_PCI_PCIE))
477		control |= OSC_PCI_EXPRESS_NATIVE_HP_CONTROL;
478
479	if (IS_ENABLED(CONFIG_HOTPLUG_PCI_SHPC))
480		control |= OSC_PCI_SHPC_NATIVE_HP_CONTROL;
481
482	if (pci_aer_available()) {
483		if (aer_acpi_firmware_first())
484			dev_info(&device->dev,
485				 "PCIe AER handled by firmware\n");
486		else
487			control |= OSC_PCI_EXPRESS_AER_CONTROL;
488	}
 
 
 
 
489
490	requested = control;
491	status = acpi_pci_osc_control_set(handle, &control,
492					  OSC_PCI_EXPRESS_CAPABILITY_CONTROL);
493	if (ACPI_SUCCESS(status)) {
494		decode_osc_control(root, "OS now controls", control);
495		if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_ASPM) {
496			/*
497			 * We have ASPM control, but the FADT indicates that
498			 * it's unsupported. Leave existing configuration
499			 * intact and prevent the OS from touching it.
500			 */
501			dev_info(&device->dev, "FADT indicates ASPM is unsupported, using BIOS configuration\n");
502			*no_aspm = 1;
503		}
504	} else {
505		decode_osc_control(root, "OS requested", requested);
506		decode_osc_control(root, "platform willing to grant", control);
507		dev_info(&device->dev, "_OSC failed (%s); disabling ASPM\n",
508			acpi_format_exception(status));
509
510		/*
511		 * We want to disable ASPM here, but aspm_disabled
512		 * needs to remain in its state from boot so that we
513		 * properly handle PCIe 1.1 devices.  So we set this
514		 * flag here, to defer the action until after the ACPI
515		 * root scan.
516		 */
517		*no_aspm = 1;
518	}
519}
520
521static int acpi_pci_root_add(struct acpi_device *device,
522			     const struct acpi_device_id *not_used)
523{
524	unsigned long long segment, bus;
525	acpi_status status;
526	int result;
527	struct acpi_pci_root *root;
528	acpi_handle handle = device->handle;
529	int no_aspm = 0;
530	bool hotadd = system_state == SYSTEM_RUNNING;
531	bool is_pcie;
532
533	root = kzalloc(sizeof(struct acpi_pci_root), GFP_KERNEL);
534	if (!root)
535		return -ENOMEM;
536
537	segment = 0;
538	status = acpi_evaluate_integer(handle, METHOD_NAME__SEG, NULL,
539				       &segment);
540	if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
541		dev_err(&device->dev,  "can't evaluate _SEG\n");
542		result = -ENODEV;
543		goto end;
544	}
545
546	/* Check _CRS first, then _BBN.  If no _BBN, default to zero. */
547	root->secondary.flags = IORESOURCE_BUS;
548	status = try_get_root_bridge_busnr(handle, &root->secondary);
549	if (ACPI_FAILURE(status)) {
550		/*
551		 * We need both the start and end of the downstream bus range
552		 * to interpret _CBA (MMCONFIG base address), so it really is
553		 * supposed to be in _CRS.  If we don't find it there, all we
554		 * can do is assume [_BBN-0xFF] or [0-0xFF].
555		 */
556		root->secondary.end = 0xFF;
557		dev_warn(&device->dev,
558			 FW_BUG "no secondary bus range in _CRS\n");
559		status = acpi_evaluate_integer(handle, METHOD_NAME__BBN,
560					       NULL, &bus);
561		if (ACPI_SUCCESS(status))
562			root->secondary.start = bus;
563		else if (status == AE_NOT_FOUND)
564			root->secondary.start = 0;
565		else {
566			dev_err(&device->dev, "can't evaluate _BBN\n");
567			result = -ENODEV;
568			goto end;
569		}
570	}
571
572	root->device = device;
573	root->segment = segment & 0xFFFF;
574	strcpy(acpi_device_name(device), ACPI_PCI_ROOT_DEVICE_NAME);
575	strcpy(acpi_device_class(device), ACPI_PCI_ROOT_CLASS);
576	device->driver_data = root;
577
578	if (hotadd && dmar_device_add(handle)) {
579		result = -ENXIO;
580		goto end;
581	}
582
583	pr_info(PREFIX "%s [%s] (domain %04x %pR)\n",
584	       acpi_device_name(device), acpi_device_bid(device),
585	       root->segment, &root->secondary);
586
587	root->mcfg_addr = acpi_pci_root_get_mcfg_addr(handle);
588
589	is_pcie = strcmp(acpi_device_hid(device), "PNP0A08") == 0;
590	negotiate_os_control(root, &no_aspm, is_pcie);
591
592	/*
593	 * TBD: Need PCI interface for enumeration/configuration of roots.
594	 */
595
596	/*
597	 * Scan the Root Bridge
598	 * --------------------
599	 * Must do this prior to any attempt to bind the root device, as the
600	 * PCI namespace does not get created until this call is made (and
601	 * thus the root bridge's pci_dev does not exist).
602	 */
603	root->bus = pci_acpi_scan_root(root);
604	if (!root->bus) {
605		dev_err(&device->dev,
606			"Bus %04x:%02x not present in PCI namespace\n",
607			root->segment, (unsigned int)root->secondary.start);
608		device->driver_data = NULL;
609		result = -ENODEV;
610		goto remove_dmar;
611	}
612
613	if (no_aspm)
614		pcie_no_aspm();
615
616	pci_acpi_add_bus_pm_notifier(device);
617	device_set_wakeup_capable(root->bus->bridge, device->wakeup.flags.valid);
618
619	if (hotadd) {
620		pcibios_resource_survey_bus(root->bus);
621		pci_assign_unassigned_root_bus_resources(root->bus);
622		/*
623		 * This is only called for the hotadd case. For the boot-time
624		 * case, we need to wait until after PCI initialization in
625		 * order to deal with IOAPICs mapped in on a PCI BAR.
626		 *
627		 * This is currently x86-specific, because acpi_ioapic_add()
628		 * is an empty function without CONFIG_ACPI_HOTPLUG_IOAPIC.
629		 * And CONFIG_ACPI_HOTPLUG_IOAPIC depends on CONFIG_X86_IO_APIC
630		 * (see drivers/acpi/Kconfig).
631		 */
632		acpi_ioapic_add(root->device->handle);
633	}
634
635	pci_lock_rescan_remove();
636	pci_bus_add_devices(root->bus);
637	pci_unlock_rescan_remove();
638	return 1;
639
640remove_dmar:
641	if (hotadd)
642		dmar_device_remove(handle);
643end:
644	kfree(root);
645	return result;
646}
647
648static void acpi_pci_root_remove(struct acpi_device *device)
649{
650	struct acpi_pci_root *root = acpi_driver_data(device);
651
652	pci_lock_rescan_remove();
653
654	pci_stop_root_bus(root->bus);
655
656	pci_ioapic_remove(root);
657	device_set_wakeup_capable(root->bus->bridge, false);
658	pci_acpi_remove_bus_pm_notifier(device);
659
660	pci_remove_root_bus(root->bus);
661	WARN_ON(acpi_ioapic_remove(root));
662
663	dmar_device_remove(device->handle);
664
665	pci_unlock_rescan_remove();
666
667	kfree(root);
668}
669
670/*
671 * Following code to support acpi_pci_root_create() is copied from
672 * arch/x86/pci/acpi.c and modified so it could be reused by x86, IA64
673 * and ARM64.
674 */
675static void acpi_pci_root_validate_resources(struct device *dev,
676					     struct list_head *resources,
677					     unsigned long type)
678{
679	LIST_HEAD(list);
680	struct resource *res1, *res2, *root = NULL;
681	struct resource_entry *tmp, *entry, *entry2;
682
683	BUG_ON((type & (IORESOURCE_MEM | IORESOURCE_IO)) == 0);
684	root = (type & IORESOURCE_MEM) ? &iomem_resource : &ioport_resource;
685
686	list_splice_init(resources, &list);
687	resource_list_for_each_entry_safe(entry, tmp, &list) {
688		bool free = false;
689		resource_size_t end;
690
691		res1 = entry->res;
692		if (!(res1->flags & type))
693			goto next;
694
695		/* Exclude non-addressable range or non-addressable portion */
696		end = min(res1->end, root->end);
697		if (end <= res1->start) {
698			dev_info(dev, "host bridge window %pR (ignored, not CPU addressable)\n",
699				 res1);
700			free = true;
701			goto next;
702		} else if (res1->end != end) {
703			dev_info(dev, "host bridge window %pR ([%#llx-%#llx] ignored, not CPU addressable)\n",
704				 res1, (unsigned long long)end + 1,
705				 (unsigned long long)res1->end);
706			res1->end = end;
707		}
708
709		resource_list_for_each_entry(entry2, resources) {
710			res2 = entry2->res;
711			if (!(res2->flags & type))
712				continue;
713
714			/*
715			 * I don't like throwing away windows because then
716			 * our resources no longer match the ACPI _CRS, but
717			 * the kernel resource tree doesn't allow overlaps.
718			 */
719			if (resource_overlaps(res1, res2)) {
720				res2->start = min(res1->start, res2->start);
721				res2->end = max(res1->end, res2->end);
722				dev_info(dev, "host bridge window expanded to %pR; %pR ignored\n",
723					 res2, res1);
724				free = true;
725				goto next;
726			}
727		}
728
729next:
730		resource_list_del(entry);
731		if (free)
732			resource_list_free_entry(entry);
733		else
734			resource_list_add_tail(entry, resources);
735	}
736}
737
738static void acpi_pci_root_remap_iospace(struct fwnode_handle *fwnode,
739			struct resource_entry *entry)
740{
741#ifdef PCI_IOBASE
742	struct resource *res = entry->res;
743	resource_size_t cpu_addr = res->start;
744	resource_size_t pci_addr = cpu_addr - entry->offset;
745	resource_size_t length = resource_size(res);
746	unsigned long port;
747
748	if (pci_register_io_range(fwnode, cpu_addr, length))
749		goto err;
750
751	port = pci_address_to_pio(cpu_addr);
752	if (port == (unsigned long)-1)
753		goto err;
754
755	res->start = port;
756	res->end = port + length - 1;
757	entry->offset = port - pci_addr;
758
759	if (pci_remap_iospace(res, cpu_addr) < 0)
760		goto err;
761
762	pr_info("Remapped I/O %pa to %pR\n", &cpu_addr, res);
763	return;
764err:
765	res->flags |= IORESOURCE_DISABLED;
766#endif
767}
768
769int acpi_pci_probe_root_resources(struct acpi_pci_root_info *info)
770{
771	int ret;
772	struct list_head *list = &info->resources;
773	struct acpi_device *device = info->bridge;
774	struct resource_entry *entry, *tmp;
775	unsigned long flags;
776
777	flags = IORESOURCE_IO | IORESOURCE_MEM | IORESOURCE_MEM_8AND16BIT;
778	ret = acpi_dev_get_resources(device, list,
779				     acpi_dev_filter_resource_type_cb,
780				     (void *)flags);
781	if (ret < 0)
782		dev_warn(&device->dev,
783			 "failed to parse _CRS method, error code %d\n", ret);
784	else if (ret == 0)
785		dev_dbg(&device->dev,
786			"no IO and memory resources present in _CRS\n");
787	else {
788		resource_list_for_each_entry_safe(entry, tmp, list) {
789			if (entry->res->flags & IORESOURCE_IO)
790				acpi_pci_root_remap_iospace(&device->fwnode,
791						entry);
792
793			if (entry->res->flags & IORESOURCE_DISABLED)
794				resource_list_destroy_entry(entry);
795			else
796				entry->res->name = info->name;
797		}
798		acpi_pci_root_validate_resources(&device->dev, list,
799						 IORESOURCE_MEM);
800		acpi_pci_root_validate_resources(&device->dev, list,
801						 IORESOURCE_IO);
802	}
803
804	return ret;
805}
806
807static void pci_acpi_root_add_resources(struct acpi_pci_root_info *info)
808{
809	struct resource_entry *entry, *tmp;
810	struct resource *res, *conflict, *root = NULL;
811
812	resource_list_for_each_entry_safe(entry, tmp, &info->resources) {
813		res = entry->res;
814		if (res->flags & IORESOURCE_MEM)
815			root = &iomem_resource;
816		else if (res->flags & IORESOURCE_IO)
817			root = &ioport_resource;
818		else
819			continue;
820
821		/*
822		 * Some legacy x86 host bridge drivers use iomem_resource and
823		 * ioport_resource as default resource pool, skip it.
824		 */
825		if (res == root)
826			continue;
827
828		conflict = insert_resource_conflict(root, res);
829		if (conflict) {
830			dev_info(&info->bridge->dev,
831				 "ignoring host bridge window %pR (conflicts with %s %pR)\n",
832				 res, conflict->name, conflict);
833			resource_list_destroy_entry(entry);
834		}
835	}
836}
837
838static void __acpi_pci_root_release_info(struct acpi_pci_root_info *info)
839{
840	struct resource *res;
841	struct resource_entry *entry, *tmp;
842
843	if (!info)
844		return;
845
846	resource_list_for_each_entry_safe(entry, tmp, &info->resources) {
847		res = entry->res;
848		if (res->parent &&
849		    (res->flags & (IORESOURCE_MEM | IORESOURCE_IO)))
850			release_resource(res);
851		resource_list_destroy_entry(entry);
852	}
853
854	info->ops->release_info(info);
855}
856
857static void acpi_pci_root_release_info(struct pci_host_bridge *bridge)
858{
859	struct resource *res;
860	struct resource_entry *entry;
861
862	resource_list_for_each_entry(entry, &bridge->windows) {
863		res = entry->res;
864		if (res->flags & IORESOURCE_IO)
865			pci_unmap_iospace(res);
866		if (res->parent &&
867		    (res->flags & (IORESOURCE_MEM | IORESOURCE_IO)))
868			release_resource(res);
869	}
870	__acpi_pci_root_release_info(bridge->release_data);
871}
872
873struct pci_bus *acpi_pci_root_create(struct acpi_pci_root *root,
874				     struct acpi_pci_root_ops *ops,
875				     struct acpi_pci_root_info *info,
876				     void *sysdata)
877{
878	int ret, busnum = root->secondary.start;
879	struct acpi_device *device = root->device;
880	int node = acpi_get_node(device->handle);
881	struct pci_bus *bus;
882	struct pci_host_bridge *host_bridge;
883	union acpi_object *obj;
884
885	info->root = root;
886	info->bridge = device;
887	info->ops = ops;
888	INIT_LIST_HEAD(&info->resources);
889	snprintf(info->name, sizeof(info->name), "PCI Bus %04x:%02x",
890		 root->segment, busnum);
891
892	if (ops->init_info && ops->init_info(info))
893		goto out_release_info;
894	if (ops->prepare_resources)
895		ret = ops->prepare_resources(info);
896	else
897		ret = acpi_pci_probe_root_resources(info);
898	if (ret < 0)
899		goto out_release_info;
900
901	pci_acpi_root_add_resources(info);
902	pci_add_resource(&info->resources, &root->secondary);
903	bus = pci_create_root_bus(NULL, busnum, ops->pci_ops,
904				  sysdata, &info->resources);
905	if (!bus)
906		goto out_release_info;
907
908	host_bridge = to_pci_host_bridge(bus->bridge);
909	if (!(root->osc_control_set & OSC_PCI_EXPRESS_NATIVE_HP_CONTROL))
910		host_bridge->native_pcie_hotplug = 0;
911	if (!(root->osc_control_set & OSC_PCI_SHPC_NATIVE_HP_CONTROL))
912		host_bridge->native_shpc_hotplug = 0;
913	if (!(root->osc_control_set & OSC_PCI_EXPRESS_AER_CONTROL))
914		host_bridge->native_aer = 0;
915	if (!(root->osc_control_set & OSC_PCI_EXPRESS_PME_CONTROL))
916		host_bridge->native_pme = 0;
917	if (!(root->osc_control_set & OSC_PCI_EXPRESS_LTR_CONTROL))
918		host_bridge->native_ltr = 0;
 
 
919
920	/*
921	 * Evaluate the "PCI Boot Configuration" _DSM Function.  If it
922	 * exists and returns 0, we must preserve any PCI resource
923	 * assignments made by firmware for this host bridge.
924	 */
925	obj = acpi_evaluate_dsm(ACPI_HANDLE(bus->bridge), &pci_acpi_dsm_guid, 1,
926	                        IGNORE_PCI_BOOT_CONFIG_DSM, NULL);
927	if (obj && obj->type == ACPI_TYPE_INTEGER && obj->integer.value == 0)
928		host_bridge->preserve_config = 1;
929	ACPI_FREE(obj);
930
931	pci_scan_child_bus(bus);
932	pci_set_host_bridge_release(host_bridge, acpi_pci_root_release_info,
933				    info);
934	if (node != NUMA_NO_NODE)
935		dev_printk(KERN_DEBUG, &bus->dev, "on NUMA node %d\n", node);
936	return bus;
937
938out_release_info:
939	__acpi_pci_root_release_info(info);
940	return NULL;
941}
942
943void __init acpi_pci_root_init(void)
944{
945	acpi_hest_init();
946	if (acpi_pci_disabled)
947		return;
948
949	pci_acpi_crs_quirks();
950	acpi_scan_add_handler_with_hotplug(&pci_root_handler, "pci_root");
951}