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 "internal.h"
24
25#define ACPI_PCI_ROOT_CLASS		"pci_bridge"
26#define ACPI_PCI_ROOT_DEVICE_NAME	"PCI Root Bridge"
27static int acpi_pci_root_add(struct acpi_device *device,
28			     const struct acpi_device_id *not_used);
29static void acpi_pci_root_remove(struct acpi_device *device);
30
31static int acpi_pci_root_scan_dependent(struct acpi_device *adev)
32{
33	acpiphp_check_host_bridge(adev);
34	return 0;
35}
36
37#define ACPI_PCIE_REQ_SUPPORT (OSC_PCI_EXT_CONFIG_SUPPORT \
38				| OSC_PCI_ASPM_SUPPORT \
39				| OSC_PCI_CLOCK_PM_SUPPORT \
40				| OSC_PCI_MSI_SUPPORT)
41
42static const struct acpi_device_id root_device_ids[] = {
43	{"PNP0A03", 0},
44	{"", 0},
45};
46
47static struct acpi_scan_handler pci_root_handler = {
48	.ids = root_device_ids,
49	.attach = acpi_pci_root_add,
50	.detach = acpi_pci_root_remove,
51	.hotplug = {
52		.enabled = true,
53		.scan_dependent = acpi_pci_root_scan_dependent,
54	},
55};
56
57static DEFINE_MUTEX(osc_lock);
58
59/**
60 * acpi_is_root_bridge - determine whether an ACPI CA node is a PCI root bridge
61 * @handle:  the ACPI CA node in question.
62 *
63 * Note: we could make this API take a struct acpi_device * instead, but
64 * for now, it's more convenient to operate on an acpi_handle.
65 */
66int acpi_is_root_bridge(acpi_handle handle)
67{
68	int ret;
69	struct acpi_device *device;
70
71	ret = acpi_bus_get_device(handle, &device);
72	if (ret)
73		return 0;
74
75	ret = acpi_match_device_ids(device, root_device_ids);
76	if (ret)
77		return 0;
78	else
79		return 1;
80}
81EXPORT_SYMBOL_GPL(acpi_is_root_bridge);
82
83static acpi_status
84get_root_bridge_busnr_callback(struct acpi_resource *resource, void *data)
85{
86	struct resource *res = data;
87	struct acpi_resource_address64 address;
88	acpi_status status;
89
90	status = acpi_resource_to_address64(resource, &address);
91	if (ACPI_FAILURE(status))
92		return AE_OK;
93
94	if ((address.address.address_length > 0) &&
95	    (address.resource_type == ACPI_BUS_NUMBER_RANGE)) {
96		res->start = address.address.minimum;
97		res->end = address.address.minimum + address.address.address_length - 1;
98	}
99
100	return AE_OK;
101}
102
103static acpi_status try_get_root_bridge_busnr(acpi_handle handle,
104					     struct resource *res)
105{
106	acpi_status status;
107
108	res->start = -1;
109	status =
110	    acpi_walk_resources(handle, METHOD_NAME__CRS,
111				get_root_bridge_busnr_callback, res);
112	if (ACPI_FAILURE(status))
113		return status;
114	if (res->start == -1)
115		return AE_ERROR;
116	return AE_OK;
117}
118
119struct pci_osc_bit_struct {
120	u32 bit;
121	char *desc;
122};
123
124static struct pci_osc_bit_struct pci_osc_support_bit[] = {
125	{ OSC_PCI_EXT_CONFIG_SUPPORT, "ExtendedConfig" },
126	{ OSC_PCI_ASPM_SUPPORT, "ASPM" },
127	{ OSC_PCI_CLOCK_PM_SUPPORT, "ClockPM" },
128	{ OSC_PCI_SEGMENT_GROUPS_SUPPORT, "Segments" },
129	{ OSC_PCI_MSI_SUPPORT, "MSI" },
130	{ OSC_PCI_EDR_SUPPORT, "EDR" },
131	{ OSC_PCI_HPX_TYPE_3_SUPPORT, "HPX-Type3" },
132};
133
134static struct pci_osc_bit_struct pci_osc_control_bit[] = {
135	{ OSC_PCI_EXPRESS_NATIVE_HP_CONTROL, "PCIeHotplug" },
136	{ OSC_PCI_SHPC_NATIVE_HP_CONTROL, "SHPCHotplug" },
137	{ OSC_PCI_EXPRESS_PME_CONTROL, "PME" },
138	{ OSC_PCI_EXPRESS_AER_CONTROL, "AER" },
139	{ OSC_PCI_EXPRESS_CAPABILITY_CONTROL, "PCIeCapability" },
140	{ OSC_PCI_EXPRESS_LTR_CONTROL, "LTR" },
141	{ OSC_PCI_EXPRESS_DPC_CONTROL, "DPC" },
142};
143
144static void decode_osc_bits(struct acpi_pci_root *root, char *msg, u32 word,
145			    struct pci_osc_bit_struct *table, int size)
146{
147	char buf[80];
148	int i, len = 0;
149	struct pci_osc_bit_struct *entry;
150
151	buf[0] = '\0';
152	for (i = 0, entry = table; i < size; i++, entry++)
153		if (word & entry->bit)
154			len += scnprintf(buf + len, sizeof(buf) - len, "%s%s",
155					len ? " " : "", entry->desc);
156
157	dev_info(&root->device->dev, "_OSC: %s [%s]\n", msg, buf);
158}
159
160static void decode_osc_support(struct acpi_pci_root *root, char *msg, u32 word)
161{
162	decode_osc_bits(root, msg, word, pci_osc_support_bit,
163			ARRAY_SIZE(pci_osc_support_bit));
164}
165
166static void decode_osc_control(struct acpi_pci_root *root, char *msg, u32 word)
167{
168	decode_osc_bits(root, msg, word, pci_osc_control_bit,
169			ARRAY_SIZE(pci_osc_control_bit));
170}
171
172static u8 pci_osc_uuid_str[] = "33DB4D5B-1FF7-401C-9657-7441C03DD766";
173
174static acpi_status acpi_pci_run_osc(acpi_handle handle,
175				    const u32 *capbuf, u32 *retval)
176{
177	struct acpi_osc_context context = {
178		.uuid_str = pci_osc_uuid_str,
179		.rev = 1,
180		.cap.length = 12,
181		.cap.pointer = (void *)capbuf,
182	};
183	acpi_status status;
184
185	status = acpi_run_osc(handle, &context);
186	if (ACPI_SUCCESS(status)) {
187		*retval = *((u32 *)(context.ret.pointer + 8));
188		kfree(context.ret.pointer);
189	}
190	return status;
191}
192
193static acpi_status acpi_pci_query_osc(struct acpi_pci_root *root,
194					u32 support,
195					u32 *control)
196{
197	acpi_status status;
198	u32 result, capbuf[3];
199
200	support &= OSC_PCI_SUPPORT_MASKS;
201	support |= root->osc_support_set;
202
203	capbuf[OSC_QUERY_DWORD] = OSC_QUERY_ENABLE;
204	capbuf[OSC_SUPPORT_DWORD] = support;
205	if (control) {
206		*control &= OSC_PCI_CONTROL_MASKS;
207		capbuf[OSC_CONTROL_DWORD] = *control | root->osc_control_set;
208	} else {
209		/* Run _OSC query only with existing controls. */
210		capbuf[OSC_CONTROL_DWORD] = root->osc_control_set;
211	}
212
213	status = acpi_pci_run_osc(root->device->handle, capbuf, &result);
214	if (ACPI_SUCCESS(status)) {
215		root->osc_support_set = support;
216		if (control)
217			*control = result;
218	}
219	return status;
220}
221
222static acpi_status acpi_pci_osc_support(struct acpi_pci_root *root, u32 flags)
223{
224	acpi_status status;
225
226	mutex_lock(&osc_lock);
227	status = acpi_pci_query_osc(root, flags, NULL);
228	mutex_unlock(&osc_lock);
229	return status;
230}
231
232struct acpi_pci_root *acpi_pci_find_root(acpi_handle handle)
233{
234	struct acpi_pci_root *root;
235	struct acpi_device *device;
236
237	if (acpi_bus_get_device(handle, &device) ||
238	    acpi_match_device_ids(device, root_device_ids))
239		return NULL;
240
241	root = acpi_driver_data(device);
242
243	return root;
244}
245EXPORT_SYMBOL_GPL(acpi_pci_find_root);
246
247struct acpi_handle_node {
248	struct list_head node;
249	acpi_handle handle;
250};
251
252/**
253 * acpi_get_pci_dev - convert ACPI CA handle to struct pci_dev
254 * @handle: the handle in question
255 *
256 * Given an ACPI CA handle, the desired PCI device is located in the
257 * list of PCI devices.
258 *
259 * If the device is found, its reference count is increased and this
260 * function returns a pointer to its data structure.  The caller must
261 * decrement the reference count by calling pci_dev_put().
262 * If no device is found, %NULL is returned.
263 */
264struct pci_dev *acpi_get_pci_dev(acpi_handle handle)
265{
266	int dev, fn;
267	unsigned long long adr;
268	acpi_status status;
269	acpi_handle phandle;
270	struct pci_bus *pbus;
271	struct pci_dev *pdev = NULL;
272	struct acpi_handle_node *node, *tmp;
273	struct acpi_pci_root *root;
274	LIST_HEAD(device_list);
275
276	/*
277	 * Walk up the ACPI CA namespace until we reach a PCI root bridge.
278	 */
279	phandle = handle;
280	while (!acpi_is_root_bridge(phandle)) {
281		node = kzalloc(sizeof(struct acpi_handle_node), GFP_KERNEL);
282		if (!node)
283			goto out;
284
285		INIT_LIST_HEAD(&node->node);
286		node->handle = phandle;
287		list_add(&node->node, &device_list);
288
289		status = acpi_get_parent(phandle, &phandle);
290		if (ACPI_FAILURE(status))
291			goto out;
292	}
293
294	root = acpi_pci_find_root(phandle);
295	if (!root)
296		goto out;
297
298	pbus = root->bus;
299
300	/*
301	 * Now, walk back down the PCI device tree until we return to our
302	 * original handle. Assumes that everything between the PCI root
303	 * bridge and the device we're looking for must be a P2P bridge.
304	 */
305	list_for_each_entry(node, &device_list, node) {
306		acpi_handle hnd = node->handle;
307		status = acpi_evaluate_integer(hnd, "_ADR", NULL, &adr);
308		if (ACPI_FAILURE(status))
309			goto out;
310		dev = (adr >> 16) & 0xffff;
311		fn  = adr & 0xffff;
312
313		pdev = pci_get_slot(pbus, PCI_DEVFN(dev, fn));
314		if (!pdev || hnd == handle)
315			break;
316
317		pbus = pdev->subordinate;
318		pci_dev_put(pdev);
319
320		/*
321		 * This function may be called for a non-PCI device that has a
322		 * PCI parent (eg. a disk under a PCI SATA controller).  In that
323		 * case pdev->subordinate will be NULL for the parent.
324		 */
325		if (!pbus) {
326			dev_dbg(&pdev->dev, "Not a PCI-to-PCI bridge\n");
327			pdev = NULL;
328			break;
329		}
330	}
331out:
332	list_for_each_entry_safe(node, tmp, &device_list, node)
333		kfree(node);
334
335	return pdev;
336}
337EXPORT_SYMBOL_GPL(acpi_get_pci_dev);
338
339/**
340 * acpi_pci_osc_control_set - Request control of PCI root _OSC features.
341 * @handle: ACPI handle of a PCI root bridge (or PCIe Root Complex).
342 * @mask: Mask of _OSC bits to request control of, place to store control mask.
343 * @req: Mask of _OSC bits the control of is essential to the caller.
344 *
345 * Run _OSC query for @mask and if that is successful, compare the returned
346 * mask of control bits with @req.  If all of the @req bits are set in the
347 * returned mask, run _OSC request for it.
348 *
349 * The variable at the @mask address may be modified regardless of whether or
350 * not the function returns success.  On success it will contain the mask of
351 * _OSC bits the BIOS has granted control of, but its contents are meaningless
352 * on failure.
353 **/
354acpi_status acpi_pci_osc_control_set(acpi_handle handle, u32 *mask, u32 req)
355{
356	struct acpi_pci_root *root;
357	acpi_status status = AE_OK;
358	u32 ctrl, capbuf[3];
359
360	if (!mask)
361		return AE_BAD_PARAMETER;
362
363	ctrl = *mask & OSC_PCI_CONTROL_MASKS;
364	if ((ctrl & req) != req)
365		return AE_TYPE;
366
367	root = acpi_pci_find_root(handle);
368	if (!root)
369		return AE_NOT_EXIST;
370
371	mutex_lock(&osc_lock);
372
373	*mask = ctrl | root->osc_control_set;
374	/* No need to evaluate _OSC if the control was already granted. */
375	if ((root->osc_control_set & ctrl) == ctrl)
376		goto out;
377
378	/* Need to check the available controls bits before requesting them. */
379	while (*mask) {
380		status = acpi_pci_query_osc(root, root->osc_support_set, mask);
381		if (ACPI_FAILURE(status))
382			goto out;
383		if (ctrl == *mask)
384			break;
385		decode_osc_control(root, "platform does not support",
386				   ctrl & ~(*mask));
387		ctrl = *mask;
388	}
389
390	if ((ctrl & req) != req) {
391		decode_osc_control(root, "not requesting control; platform does not support",
392				   req & ~(ctrl));
393		status = AE_SUPPORT;
394		goto out;
395	}
396
397	capbuf[OSC_QUERY_DWORD] = 0;
398	capbuf[OSC_SUPPORT_DWORD] = root->osc_support_set;
399	capbuf[OSC_CONTROL_DWORD] = ctrl;
400	status = acpi_pci_run_osc(handle, capbuf, mask);
401	if (ACPI_SUCCESS(status))
402		root->osc_control_set = *mask;
403out:
404	mutex_unlock(&osc_lock);
405	return status;
406}
407EXPORT_SYMBOL(acpi_pci_osc_control_set);
408
409static void negotiate_os_control(struct acpi_pci_root *root, int *no_aspm,
410				 bool is_pcie)
411{
412	u32 support, control, requested;
413	acpi_status status;
414	struct acpi_device *device = root->device;
415	acpi_handle handle = device->handle;
416
417	/*
418	 * Apple always return failure on _OSC calls when _OSI("Darwin") has
419	 * been called successfully. We know the feature set supported by the
420	 * platform, so avoid calling _OSC at all
421	 */
422	if (x86_apple_machine) {
423		root->osc_control_set = ~OSC_PCI_EXPRESS_PME_CONTROL;
424		decode_osc_control(root, "OS assumes control of",
425				   root->osc_control_set);
426		return;
427	}
428
429	/*
430	 * All supported architectures that use ACPI have support for
431	 * PCI domains, so we indicate this in _OSC support capabilities.
432	 */
433	support = OSC_PCI_SEGMENT_GROUPS_SUPPORT;
434	support |= OSC_PCI_HPX_TYPE_3_SUPPORT;
435	if (pci_ext_cfg_avail())
436		support |= OSC_PCI_EXT_CONFIG_SUPPORT;
437	if (pcie_aspm_support_enabled())
438		support |= OSC_PCI_ASPM_SUPPORT | OSC_PCI_CLOCK_PM_SUPPORT;
439	if (pci_msi_enabled())
440		support |= OSC_PCI_MSI_SUPPORT;
441	if (IS_ENABLED(CONFIG_PCIE_EDR))
442		support |= OSC_PCI_EDR_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		control |= OSC_PCI_EXPRESS_AER_CONTROL;
484
485	/*
486	 * Per the Downstream Port Containment Related Enhancements ECN to
487	 * the PCI Firmware Spec, r3.2, sec 4.5.1, table 4-5,
488	 * OSC_PCI_EXPRESS_DPC_CONTROL indicates the OS supports both DPC
489	 * and EDR.
490	 */
491	if (IS_ENABLED(CONFIG_PCIE_DPC) && IS_ENABLED(CONFIG_PCIE_EDR))
492		control |= OSC_PCI_EXPRESS_DPC_CONTROL;
493
494	requested = control;
495	status = acpi_pci_osc_control_set(handle, &control,
496					  OSC_PCI_EXPRESS_CAPABILITY_CONTROL);
497	if (ACPI_SUCCESS(status)) {
498		decode_osc_control(root, "OS now controls", control);
499		if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_ASPM) {
500			/*
501			 * We have ASPM control, but the FADT indicates that
502			 * it's unsupported. Leave existing configuration
503			 * intact and prevent the OS from touching it.
504			 */
505			dev_info(&device->dev, "FADT indicates ASPM is unsupported, using BIOS configuration\n");
506			*no_aspm = 1;
507		}
508	} else {
509		decode_osc_control(root, "OS requested", requested);
510		decode_osc_control(root, "platform willing to grant", control);
511		dev_info(&device->dev, "_OSC failed (%s); disabling ASPM\n",
512			acpi_format_exception(status));
513
514		/*
515		 * We want to disable ASPM here, but aspm_disabled
516		 * needs to remain in its state from boot so that we
517		 * properly handle PCIe 1.1 devices.  So we set this
518		 * flag here, to defer the action until after the ACPI
519		 * root scan.
520		 */
521		*no_aspm = 1;
522	}
523}
524
525static int acpi_pci_root_add(struct acpi_device *device,
526			     const struct acpi_device_id *not_used)
527{
528	unsigned long long segment, bus;
529	acpi_status status;
530	int result;
531	struct acpi_pci_root *root;
532	acpi_handle handle = device->handle;
533	int no_aspm = 0;
534	bool hotadd = system_state == SYSTEM_RUNNING;
535	bool is_pcie;
536
537	root = kzalloc(sizeof(struct acpi_pci_root), GFP_KERNEL);
538	if (!root)
539		return -ENOMEM;
540
541	segment = 0;
542	status = acpi_evaluate_integer(handle, METHOD_NAME__SEG, NULL,
543				       &segment);
544	if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
545		dev_err(&device->dev,  "can't evaluate _SEG\n");
546		result = -ENODEV;
547		goto end;
548	}
549
550	/* Check _CRS first, then _BBN.  If no _BBN, default to zero. */
551	root->secondary.flags = IORESOURCE_BUS;
552	status = try_get_root_bridge_busnr(handle, &root->secondary);
553	if (ACPI_FAILURE(status)) {
554		/*
555		 * We need both the start and end of the downstream bus range
556		 * to interpret _CBA (MMCONFIG base address), so it really is
557		 * supposed to be in _CRS.  If we don't find it there, all we
558		 * can do is assume [_BBN-0xFF] or [0-0xFF].
559		 */
560		root->secondary.end = 0xFF;
561		dev_warn(&device->dev,
562			 FW_BUG "no secondary bus range in _CRS\n");
563		status = acpi_evaluate_integer(handle, METHOD_NAME__BBN,
564					       NULL, &bus);
565		if (ACPI_SUCCESS(status))
566			root->secondary.start = bus;
567		else if (status == AE_NOT_FOUND)
568			root->secondary.start = 0;
569		else {
570			dev_err(&device->dev, "can't evaluate _BBN\n");
571			result = -ENODEV;
572			goto end;
573		}
574	}
575
576	root->device = device;
577	root->segment = segment & 0xFFFF;
578	strcpy(acpi_device_name(device), ACPI_PCI_ROOT_DEVICE_NAME);
579	strcpy(acpi_device_class(device), ACPI_PCI_ROOT_CLASS);
580	device->driver_data = root;
581
582	if (hotadd && dmar_device_add(handle)) {
583		result = -ENXIO;
584		goto end;
585	}
586
587	pr_info(PREFIX "%s [%s] (domain %04x %pR)\n",
588	       acpi_device_name(device), acpi_device_bid(device),
589	       root->segment, &root->secondary);
590
591	root->mcfg_addr = acpi_pci_root_get_mcfg_addr(handle);
592
593	is_pcie = strcmp(acpi_device_hid(device), "PNP0A08") == 0;
594	negotiate_os_control(root, &no_aspm, is_pcie);
595
596	/*
597	 * TBD: Need PCI interface for enumeration/configuration of roots.
598	 */
599
600	/*
601	 * Scan the Root Bridge
602	 * --------------------
603	 * Must do this prior to any attempt to bind the root device, as the
604	 * PCI namespace does not get created until this call is made (and
605	 * thus the root bridge's pci_dev does not exist).
606	 */
607	root->bus = pci_acpi_scan_root(root);
608	if (!root->bus) {
609		dev_err(&device->dev,
610			"Bus %04x:%02x not present in PCI namespace\n",
611			root->segment, (unsigned int)root->secondary.start);
612		device->driver_data = NULL;
613		result = -ENODEV;
614		goto remove_dmar;
615	}
616
617	if (no_aspm)
618		pcie_no_aspm();
619
620	pci_acpi_add_bus_pm_notifier(device);
621	device_set_wakeup_capable(root->bus->bridge, device->wakeup.flags.valid);
622
623	if (hotadd) {
624		pcibios_resource_survey_bus(root->bus);
625		pci_assign_unassigned_root_bus_resources(root->bus);
626		/*
627		 * This is only called for the hotadd case. For the boot-time
628		 * case, we need to wait until after PCI initialization in
629		 * order to deal with IOAPICs mapped in on a PCI BAR.
630		 *
631		 * This is currently x86-specific, because acpi_ioapic_add()
632		 * is an empty function without CONFIG_ACPI_HOTPLUG_IOAPIC.
633		 * And CONFIG_ACPI_HOTPLUG_IOAPIC depends on CONFIG_X86_IO_APIC
634		 * (see drivers/acpi/Kconfig).
635		 */
636		acpi_ioapic_add(root->device->handle);
637	}
638
639	pci_lock_rescan_remove();
640	pci_bus_add_devices(root->bus);
641	pci_unlock_rescan_remove();
642	return 1;
643
644remove_dmar:
645	if (hotadd)
646		dmar_device_remove(handle);
647end:
648	kfree(root);
649	return result;
650}
651
652static void acpi_pci_root_remove(struct acpi_device *device)
653{
654	struct acpi_pci_root *root = acpi_driver_data(device);
655
656	pci_lock_rescan_remove();
657
658	pci_stop_root_bus(root->bus);
659
660	pci_ioapic_remove(root);
661	device_set_wakeup_capable(root->bus->bridge, false);
662	pci_acpi_remove_bus_pm_notifier(device);
663
664	pci_remove_root_bus(root->bus);
665	WARN_ON(acpi_ioapic_remove(root));
666
667	dmar_device_remove(device->handle);
668
669	pci_unlock_rescan_remove();
670
671	kfree(root);
672}
673
674/*
675 * Following code to support acpi_pci_root_create() is copied from
676 * arch/x86/pci/acpi.c and modified so it could be reused by x86, IA64
677 * and ARM64.
678 */
679static void acpi_pci_root_validate_resources(struct device *dev,
680					     struct list_head *resources,
681					     unsigned long type)
682{
683	LIST_HEAD(list);
684	struct resource *res1, *res2, *root = NULL;
685	struct resource_entry *tmp, *entry, *entry2;
686
687	BUG_ON((type & (IORESOURCE_MEM | IORESOURCE_IO)) == 0);
688	root = (type & IORESOURCE_MEM) ? &iomem_resource : &ioport_resource;
689
690	list_splice_init(resources, &list);
691	resource_list_for_each_entry_safe(entry, tmp, &list) {
692		bool free = false;
693		resource_size_t end;
694
695		res1 = entry->res;
696		if (!(res1->flags & type))
697			goto next;
698
699		/* Exclude non-addressable range or non-addressable portion */
700		end = min(res1->end, root->end);
701		if (end <= res1->start) {
702			dev_info(dev, "host bridge window %pR (ignored, not CPU addressable)\n",
703				 res1);
704			free = true;
705			goto next;
706		} else if (res1->end != end) {
707			dev_info(dev, "host bridge window %pR ([%#llx-%#llx] ignored, not CPU addressable)\n",
708				 res1, (unsigned long long)end + 1,
709				 (unsigned long long)res1->end);
710			res1->end = end;
711		}
712
713		resource_list_for_each_entry(entry2, resources) {
714			res2 = entry2->res;
715			if (!(res2->flags & type))
716				continue;
717
718			/*
719			 * I don't like throwing away windows because then
720			 * our resources no longer match the ACPI _CRS, but
721			 * the kernel resource tree doesn't allow overlaps.
722			 */
723			if (resource_overlaps(res1, res2)) {
724				res2->start = min(res1->start, res2->start);
725				res2->end = max(res1->end, res2->end);
726				dev_info(dev, "host bridge window expanded to %pR; %pR ignored\n",
727					 res2, res1);
728				free = true;
729				goto next;
730			}
731		}
732
733next:
734		resource_list_del(entry);
735		if (free)
736			resource_list_free_entry(entry);
737		else
738			resource_list_add_tail(entry, resources);
739	}
740}
741
742static void acpi_pci_root_remap_iospace(struct fwnode_handle *fwnode,
743			struct resource_entry *entry)
744{
745#ifdef PCI_IOBASE
746	struct resource *res = entry->res;
747	resource_size_t cpu_addr = res->start;
748	resource_size_t pci_addr = cpu_addr - entry->offset;
749	resource_size_t length = resource_size(res);
750	unsigned long port;
751
752	if (pci_register_io_range(fwnode, cpu_addr, length))
753		goto err;
754
755	port = pci_address_to_pio(cpu_addr);
756	if (port == (unsigned long)-1)
757		goto err;
758
759	res->start = port;
760	res->end = port + length - 1;
761	entry->offset = port - pci_addr;
762
763	if (pci_remap_iospace(res, cpu_addr) < 0)
764		goto err;
765
766	pr_info("Remapped I/O %pa to %pR\n", &cpu_addr, res);
767	return;
768err:
769	res->flags |= IORESOURCE_DISABLED;
770#endif
771}
772
773int acpi_pci_probe_root_resources(struct acpi_pci_root_info *info)
774{
775	int ret;
776	struct list_head *list = &info->resources;
777	struct acpi_device *device = info->bridge;
778	struct resource_entry *entry, *tmp;
779	unsigned long flags;
780
781	flags = IORESOURCE_IO | IORESOURCE_MEM | IORESOURCE_MEM_8AND16BIT;
782	ret = acpi_dev_get_resources(device, list,
783				     acpi_dev_filter_resource_type_cb,
784				     (void *)flags);
785	if (ret < 0)
786		dev_warn(&device->dev,
787			 "failed to parse _CRS method, error code %d\n", ret);
788	else if (ret == 0)
789		dev_dbg(&device->dev,
790			"no IO and memory resources present in _CRS\n");
791	else {
792		resource_list_for_each_entry_safe(entry, tmp, list) {
793			if (entry->res->flags & IORESOURCE_IO)
794				acpi_pci_root_remap_iospace(&device->fwnode,
795						entry);
796
797			if (entry->res->flags & IORESOURCE_DISABLED)
798				resource_list_destroy_entry(entry);
799			else
800				entry->res->name = info->name;
801		}
802		acpi_pci_root_validate_resources(&device->dev, list,
803						 IORESOURCE_MEM);
804		acpi_pci_root_validate_resources(&device->dev, list,
805						 IORESOURCE_IO);
806	}
807
808	return ret;
809}
810
811static void pci_acpi_root_add_resources(struct acpi_pci_root_info *info)
812{
813	struct resource_entry *entry, *tmp;
814	struct resource *res, *conflict, *root = NULL;
815
816	resource_list_for_each_entry_safe(entry, tmp, &info->resources) {
817		res = entry->res;
818		if (res->flags & IORESOURCE_MEM)
819			root = &iomem_resource;
820		else if (res->flags & IORESOURCE_IO)
821			root = &ioport_resource;
822		else
823			continue;
824
825		/*
826		 * Some legacy x86 host bridge drivers use iomem_resource and
827		 * ioport_resource as default resource pool, skip it.
828		 */
829		if (res == root)
830			continue;
831
832		conflict = insert_resource_conflict(root, res);
833		if (conflict) {
834			dev_info(&info->bridge->dev,
835				 "ignoring host bridge window %pR (conflicts with %s %pR)\n",
836				 res, conflict->name, conflict);
837			resource_list_destroy_entry(entry);
838		}
839	}
840}
841
842static void __acpi_pci_root_release_info(struct acpi_pci_root_info *info)
843{
844	struct resource *res;
845	struct resource_entry *entry, *tmp;
846
847	if (!info)
848		return;
849
850	resource_list_for_each_entry_safe(entry, tmp, &info->resources) {
851		res = entry->res;
852		if (res->parent &&
853		    (res->flags & (IORESOURCE_MEM | IORESOURCE_IO)))
854			release_resource(res);
855		resource_list_destroy_entry(entry);
856	}
857
858	info->ops->release_info(info);
859}
860
861static void acpi_pci_root_release_info(struct pci_host_bridge *bridge)
862{
863	struct resource *res;
864	struct resource_entry *entry;
865
866	resource_list_for_each_entry(entry, &bridge->windows) {
867		res = entry->res;
868		if (res->flags & IORESOURCE_IO)
869			pci_unmap_iospace(res);
870		if (res->parent &&
871		    (res->flags & (IORESOURCE_MEM | IORESOURCE_IO)))
872			release_resource(res);
873	}
874	__acpi_pci_root_release_info(bridge->release_data);
875}
876
877struct pci_bus *acpi_pci_root_create(struct acpi_pci_root *root,
878				     struct acpi_pci_root_ops *ops,
879				     struct acpi_pci_root_info *info,
880				     void *sysdata)
881{
882	int ret, busnum = root->secondary.start;
883	struct acpi_device *device = root->device;
884	int node = acpi_get_node(device->handle);
885	struct pci_bus *bus;
886	struct pci_host_bridge *host_bridge;
887	union acpi_object *obj;
888
889	info->root = root;
890	info->bridge = device;
891	info->ops = ops;
892	INIT_LIST_HEAD(&info->resources);
893	snprintf(info->name, sizeof(info->name), "PCI Bus %04x:%02x",
894		 root->segment, busnum);
895
896	if (ops->init_info && ops->init_info(info))
897		goto out_release_info;
898	if (ops->prepare_resources)
899		ret = ops->prepare_resources(info);
900	else
901		ret = acpi_pci_probe_root_resources(info);
902	if (ret < 0)
903		goto out_release_info;
904
905	pci_acpi_root_add_resources(info);
906	pci_add_resource(&info->resources, &root->secondary);
907	bus = pci_create_root_bus(NULL, busnum, ops->pci_ops,
908				  sysdata, &info->resources);
909	if (!bus)
910		goto out_release_info;
911
912	host_bridge = to_pci_host_bridge(bus->bridge);
913	if (!(root->osc_control_set & OSC_PCI_EXPRESS_NATIVE_HP_CONTROL))
914		host_bridge->native_pcie_hotplug = 0;
915	if (!(root->osc_control_set & OSC_PCI_SHPC_NATIVE_HP_CONTROL))
916		host_bridge->native_shpc_hotplug = 0;
917	if (!(root->osc_control_set & OSC_PCI_EXPRESS_AER_CONTROL))
918		host_bridge->native_aer = 0;
919	if (!(root->osc_control_set & OSC_PCI_EXPRESS_PME_CONTROL))
920		host_bridge->native_pme = 0;
921	if (!(root->osc_control_set & OSC_PCI_EXPRESS_LTR_CONTROL))
922		host_bridge->native_ltr = 0;
923	if (!(root->osc_control_set & OSC_PCI_EXPRESS_DPC_CONTROL))
924		host_bridge->native_dpc = 0;
925
926	/*
927	 * Evaluate the "PCI Boot Configuration" _DSM Function.  If it
928	 * exists and returns 0, we must preserve any PCI resource
929	 * assignments made by firmware for this host bridge.
930	 */
931	obj = acpi_evaluate_dsm(ACPI_HANDLE(bus->bridge), &pci_acpi_dsm_guid, 1,
932				DSM_PCI_PRESERVE_BOOT_CONFIG, NULL);
933	if (obj && obj->type == ACPI_TYPE_INTEGER && obj->integer.value == 0)
934		host_bridge->preserve_config = 1;
935	ACPI_FREE(obj);
936
937	pci_scan_child_bus(bus);
938	pci_set_host_bridge_release(host_bridge, acpi_pci_root_release_info,
939				    info);
940	if (node != NUMA_NO_NODE)
941		dev_printk(KERN_DEBUG, &bus->dev, "on NUMA node %d\n", node);
942	return bus;
943
944out_release_info:
945	__acpi_pci_root_release_info(info);
946	return NULL;
947}
948
949void __init acpi_pci_root_init(void)
950{
951	if (acpi_pci_disabled)
952		return;
953
954	pci_acpi_crs_quirks();
955	acpi_scan_add_handler_with_hotplug(&pci_root_handler, "pci_root");
956}
957