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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}
v4.10.11
 
  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 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 20 */
 21
 22#include <linux/kernel.h>
 23#include <linux/module.h>
 24#include <linux/init.h>
 25#include <linux/types.h>
 26#include <linux/mutex.h>
 27#include <linux/pm.h>
 28#include <linux/pm_runtime.h>
 29#include <linux/pci.h>
 30#include <linux/pci-acpi.h>
 31#include <linux/pci-aspm.h>
 32#include <linux/dmar.h>
 33#include <linux/acpi.h>
 34#include <linux/slab.h>
 35#include <linux/dmi.h>
 
 36#include <acpi/apei.h>	/* for acpi_hest_init() */
 37
 38#include "internal.h"
 39
 40#define _COMPONENT		ACPI_PCI_COMPONENT
 41ACPI_MODULE_NAME("pci_root");
 42#define ACPI_PCI_ROOT_CLASS		"pci_bridge"
 43#define ACPI_PCI_ROOT_DEVICE_NAME	"PCI Root Bridge"
 44static int acpi_pci_root_add(struct acpi_device *device,
 45			     const struct acpi_device_id *not_used);
 46static void acpi_pci_root_remove(struct acpi_device *device);
 47
 48static int acpi_pci_root_scan_dependent(struct acpi_device *adev)
 49{
 50	acpiphp_check_host_bridge(adev);
 51	return 0;
 52}
 53
 54#define ACPI_PCIE_REQ_SUPPORT (OSC_PCI_EXT_CONFIG_SUPPORT \
 55				| OSC_PCI_ASPM_SUPPORT \
 56				| OSC_PCI_CLOCK_PM_SUPPORT \
 57				| OSC_PCI_MSI_SUPPORT)
 58
 59static const struct acpi_device_id root_device_ids[] = {
 60	{"PNP0A03", 0},
 61	{"", 0},
 62};
 63
 64static struct acpi_scan_handler pci_root_handler = {
 65	.ids = root_device_ids,
 66	.attach = acpi_pci_root_add,
 67	.detach = acpi_pci_root_remove,
 68	.hotplug = {
 69		.enabled = true,
 70		.scan_dependent = acpi_pci_root_scan_dependent,
 71	},
 72};
 73
 74static DEFINE_MUTEX(osc_lock);
 75
 76/**
 77 * acpi_is_root_bridge - determine whether an ACPI CA node is a PCI root bridge
 78 * @handle - the ACPI CA node in question.
 79 *
 80 * Note: we could make this API take a struct acpi_device * instead, but
 81 * for now, it's more convenient to operate on an acpi_handle.
 82 */
 83int acpi_is_root_bridge(acpi_handle handle)
 84{
 85	int ret;
 86	struct acpi_device *device;
 87
 88	ret = acpi_bus_get_device(handle, &device);
 89	if (ret)
 90		return 0;
 91
 92	ret = acpi_match_device_ids(device, root_device_ids);
 93	if (ret)
 94		return 0;
 95	else
 96		return 1;
 97}
 98EXPORT_SYMBOL_GPL(acpi_is_root_bridge);
 99
100static acpi_status
101get_root_bridge_busnr_callback(struct acpi_resource *resource, void *data)
102{
103	struct resource *res = data;
104	struct acpi_resource_address64 address;
105	acpi_status status;
106
107	status = acpi_resource_to_address64(resource, &address);
108	if (ACPI_FAILURE(status))
109		return AE_OK;
110
111	if ((address.address.address_length > 0) &&
112	    (address.resource_type == ACPI_BUS_NUMBER_RANGE)) {
113		res->start = address.address.minimum;
114		res->end = address.address.minimum + address.address.address_length - 1;
115	}
116
117	return AE_OK;
118}
119
120static acpi_status try_get_root_bridge_busnr(acpi_handle handle,
121					     struct resource *res)
122{
123	acpi_status status;
124
125	res->start = -1;
126	status =
127	    acpi_walk_resources(handle, METHOD_NAME__CRS,
128				get_root_bridge_busnr_callback, res);
129	if (ACPI_FAILURE(status))
130		return status;
131	if (res->start == -1)
132		return AE_ERROR;
133	return AE_OK;
134}
135
136struct pci_osc_bit_struct {
137	u32 bit;
138	char *desc;
139};
140
141static struct pci_osc_bit_struct pci_osc_support_bit[] = {
142	{ OSC_PCI_EXT_CONFIG_SUPPORT, "ExtendedConfig" },
143	{ OSC_PCI_ASPM_SUPPORT, "ASPM" },
144	{ OSC_PCI_CLOCK_PM_SUPPORT, "ClockPM" },
145	{ OSC_PCI_SEGMENT_GROUPS_SUPPORT, "Segments" },
146	{ OSC_PCI_MSI_SUPPORT, "MSI" },
 
 
147};
148
149static struct pci_osc_bit_struct pci_osc_control_bit[] = {
150	{ OSC_PCI_EXPRESS_NATIVE_HP_CONTROL, "PCIeHotplug" },
151	{ OSC_PCI_SHPC_NATIVE_HP_CONTROL, "SHPCHotplug" },
152	{ OSC_PCI_EXPRESS_PME_CONTROL, "PME" },
153	{ OSC_PCI_EXPRESS_AER_CONTROL, "AER" },
154	{ OSC_PCI_EXPRESS_CAPABILITY_CONTROL, "PCIeCapability" },
 
 
155};
156
157static void decode_osc_bits(struct acpi_pci_root *root, char *msg, u32 word,
158			    struct pci_osc_bit_struct *table, int size)
159{
160	char buf[80];
161	int i, len = 0;
162	struct pci_osc_bit_struct *entry;
163
164	buf[0] = '\0';
165	for (i = 0, entry = table; i < size; i++, entry++)
166		if (word & entry->bit)
167			len += snprintf(buf + len, sizeof(buf) - len, "%s%s",
168					len ? " " : "", entry->desc);
169
170	dev_info(&root->device->dev, "_OSC: %s [%s]\n", msg, buf);
171}
172
173static void decode_osc_support(struct acpi_pci_root *root, char *msg, u32 word)
174{
175	decode_osc_bits(root, msg, word, pci_osc_support_bit,
176			ARRAY_SIZE(pci_osc_support_bit));
177}
178
179static void decode_osc_control(struct acpi_pci_root *root, char *msg, u32 word)
180{
181	decode_osc_bits(root, msg, word, pci_osc_control_bit,
182			ARRAY_SIZE(pci_osc_control_bit));
183}
184
185static u8 pci_osc_uuid_str[] = "33DB4D5B-1FF7-401C-9657-7441C03DD766";
186
187static acpi_status acpi_pci_run_osc(acpi_handle handle,
188				    const u32 *capbuf, u32 *retval)
189{
190	struct acpi_osc_context context = {
191		.uuid_str = pci_osc_uuid_str,
192		.rev = 1,
193		.cap.length = 12,
194		.cap.pointer = (void *)capbuf,
195	};
196	acpi_status status;
197
198	status = acpi_run_osc(handle, &context);
199	if (ACPI_SUCCESS(status)) {
200		*retval = *((u32 *)(context.ret.pointer + 8));
201		kfree(context.ret.pointer);
202	}
203	return status;
204}
205
206static acpi_status acpi_pci_query_osc(struct acpi_pci_root *root,
207					u32 support,
208					u32 *control)
209{
210	acpi_status status;
211	u32 result, capbuf[3];
212
213	support &= OSC_PCI_SUPPORT_MASKS;
214	support |= root->osc_support_set;
215
216	capbuf[OSC_QUERY_DWORD] = OSC_QUERY_ENABLE;
217	capbuf[OSC_SUPPORT_DWORD] = support;
218	if (control) {
219		*control &= OSC_PCI_CONTROL_MASKS;
220		capbuf[OSC_CONTROL_DWORD] = *control | root->osc_control_set;
221	} else {
222		/* Run _OSC query only with existing controls. */
223		capbuf[OSC_CONTROL_DWORD] = root->osc_control_set;
224	}
225
226	status = acpi_pci_run_osc(root->device->handle, capbuf, &result);
227	if (ACPI_SUCCESS(status)) {
228		root->osc_support_set = support;
229		if (control)
230			*control = result;
231	}
232	return status;
233}
234
235static acpi_status acpi_pci_osc_support(struct acpi_pci_root *root, u32 flags)
236{
237	acpi_status status;
238
239	mutex_lock(&osc_lock);
240	status = acpi_pci_query_osc(root, flags, NULL);
241	mutex_unlock(&osc_lock);
242	return status;
243}
244
245struct acpi_pci_root *acpi_pci_find_root(acpi_handle handle)
246{
247	struct acpi_pci_root *root;
248	struct acpi_device *device;
249
250	if (acpi_bus_get_device(handle, &device) ||
251	    acpi_match_device_ids(device, root_device_ids))
252		return NULL;
253
254	root = acpi_driver_data(device);
255
256	return root;
257}
258EXPORT_SYMBOL_GPL(acpi_pci_find_root);
259
260struct acpi_handle_node {
261	struct list_head node;
262	acpi_handle handle;
263};
264
265/**
266 * acpi_get_pci_dev - convert ACPI CA handle to struct pci_dev
267 * @handle: the handle in question
268 *
269 * Given an ACPI CA handle, the desired PCI device is located in the
270 * list of PCI devices.
271 *
272 * If the device is found, its reference count is increased and this
273 * function returns a pointer to its data structure.  The caller must
274 * decrement the reference count by calling pci_dev_put().
275 * If no device is found, %NULL is returned.
276 */
277struct pci_dev *acpi_get_pci_dev(acpi_handle handle)
278{
279	int dev, fn;
280	unsigned long long adr;
281	acpi_status status;
282	acpi_handle phandle;
283	struct pci_bus *pbus;
284	struct pci_dev *pdev = NULL;
285	struct acpi_handle_node *node, *tmp;
286	struct acpi_pci_root *root;
287	LIST_HEAD(device_list);
288
289	/*
290	 * Walk up the ACPI CA namespace until we reach a PCI root bridge.
291	 */
292	phandle = handle;
293	while (!acpi_is_root_bridge(phandle)) {
294		node = kzalloc(sizeof(struct acpi_handle_node), GFP_KERNEL);
295		if (!node)
296			goto out;
297
298		INIT_LIST_HEAD(&node->node);
299		node->handle = phandle;
300		list_add(&node->node, &device_list);
301
302		status = acpi_get_parent(phandle, &phandle);
303		if (ACPI_FAILURE(status))
304			goto out;
305	}
306
307	root = acpi_pci_find_root(phandle);
308	if (!root)
309		goto out;
310
311	pbus = root->bus;
312
313	/*
314	 * Now, walk back down the PCI device tree until we return to our
315	 * original handle. Assumes that everything between the PCI root
316	 * bridge and the device we're looking for must be a P2P bridge.
317	 */
318	list_for_each_entry(node, &device_list, node) {
319		acpi_handle hnd = node->handle;
320		status = acpi_evaluate_integer(hnd, "_ADR", NULL, &adr);
321		if (ACPI_FAILURE(status))
322			goto out;
323		dev = (adr >> 16) & 0xffff;
324		fn  = adr & 0xffff;
325
326		pdev = pci_get_slot(pbus, PCI_DEVFN(dev, fn));
327		if (!pdev || hnd == handle)
328			break;
329
330		pbus = pdev->subordinate;
331		pci_dev_put(pdev);
332
333		/*
334		 * This function may be called for a non-PCI device that has a
335		 * PCI parent (eg. a disk under a PCI SATA controller).  In that
336		 * case pdev->subordinate will be NULL for the parent.
337		 */
338		if (!pbus) {
339			dev_dbg(&pdev->dev, "Not a PCI-to-PCI bridge\n");
340			pdev = NULL;
341			break;
342		}
343	}
344out:
345	list_for_each_entry_safe(node, tmp, &device_list, node)
346		kfree(node);
347
348	return pdev;
349}
350EXPORT_SYMBOL_GPL(acpi_get_pci_dev);
351
352/**
353 * acpi_pci_osc_control_set - Request control of PCI root _OSC features.
354 * @handle: ACPI handle of a PCI root bridge (or PCIe Root Complex).
355 * @mask: Mask of _OSC bits to request control of, place to store control mask.
356 * @req: Mask of _OSC bits the control of is essential to the caller.
357 *
358 * Run _OSC query for @mask and if that is successful, compare the returned
359 * mask of control bits with @req.  If all of the @req bits are set in the
360 * returned mask, run _OSC request for it.
361 *
362 * The variable at the @mask address may be modified regardless of whether or
363 * not the function returns success.  On success it will contain the mask of
364 * _OSC bits the BIOS has granted control of, but its contents are meaningless
365 * on failure.
366 **/
367acpi_status acpi_pci_osc_control_set(acpi_handle handle, u32 *mask, u32 req)
368{
369	struct acpi_pci_root *root;
370	acpi_status status = AE_OK;
371	u32 ctrl, capbuf[3];
372
373	if (!mask)
374		return AE_BAD_PARAMETER;
375
376	ctrl = *mask & OSC_PCI_CONTROL_MASKS;
377	if ((ctrl & req) != req)
378		return AE_TYPE;
379
380	root = acpi_pci_find_root(handle);
381	if (!root)
382		return AE_NOT_EXIST;
383
384	mutex_lock(&osc_lock);
385
386	*mask = ctrl | root->osc_control_set;
387	/* No need to evaluate _OSC if the control was already granted. */
388	if ((root->osc_control_set & ctrl) == ctrl)
389		goto out;
390
391	/* Need to check the available controls bits before requesting them. */
392	while (*mask) {
393		status = acpi_pci_query_osc(root, root->osc_support_set, mask);
394		if (ACPI_FAILURE(status))
395			goto out;
396		if (ctrl == *mask)
397			break;
398		decode_osc_control(root, "platform does not support",
399				   ctrl & ~(*mask));
400		ctrl = *mask;
401	}
402
403	if ((ctrl & req) != req) {
404		decode_osc_control(root, "not requesting control; platform does not support",
405				   req & ~(ctrl));
406		status = AE_SUPPORT;
407		goto out;
408	}
409
410	capbuf[OSC_QUERY_DWORD] = 0;
411	capbuf[OSC_SUPPORT_DWORD] = root->osc_support_set;
412	capbuf[OSC_CONTROL_DWORD] = ctrl;
413	status = acpi_pci_run_osc(handle, capbuf, mask);
414	if (ACPI_SUCCESS(status))
415		root->osc_control_set = *mask;
416out:
417	mutex_unlock(&osc_lock);
418	return status;
419}
420EXPORT_SYMBOL(acpi_pci_osc_control_set);
421
422static void negotiate_os_control(struct acpi_pci_root *root, int *no_aspm)
 
423{
424	u32 support, control, requested;
425	acpi_status status;
426	struct acpi_device *device = root->device;
427	acpi_handle handle = device->handle;
428
429	/*
430	 * Apple always return failure on _OSC calls when _OSI("Darwin") has
431	 * been called successfully. We know the feature set supported by the
432	 * platform, so avoid calling _OSC at all
433	 */
434
435	if (dmi_match(DMI_SYS_VENDOR, "Apple Inc.")) {
436		root->osc_control_set = ~OSC_PCI_EXPRESS_PME_CONTROL;
437		decode_osc_control(root, "OS assumes control of",
438				   root->osc_control_set);
439		return;
440	}
441
442	/*
443	 * All supported architectures that use ACPI have support for
444	 * PCI domains, so we indicate this in _OSC support capabilities.
445	 */
446	support = OSC_PCI_SEGMENT_GROUPS_SUPPORT;
 
447	if (pci_ext_cfg_avail())
448		support |= OSC_PCI_EXT_CONFIG_SUPPORT;
449	if (pcie_aspm_support_enabled())
450		support |= OSC_PCI_ASPM_SUPPORT | OSC_PCI_CLOCK_PM_SUPPORT;
451	if (pci_msi_enabled())
452		support |= OSC_PCI_MSI_SUPPORT;
 
 
453
454	decode_osc_support(root, "OS supports", support);
455	status = acpi_pci_osc_support(root, support);
456	if (ACPI_FAILURE(status)) {
457		dev_info(&device->dev, "_OSC failed (%s); disabling ASPM\n",
458			 acpi_format_exception(status));
459		*no_aspm = 1;
 
 
 
 
 
 
 
 
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_NATIVE_HP_CONTROL
476		| OSC_PCI_EXPRESS_PME_CONTROL;
477
478	if (pci_aer_available()) {
479		if (aer_acpi_firmware_first())
480			dev_info(&device->dev,
481				 "PCIe AER handled by firmware\n");
482		else
483			control |= OSC_PCI_EXPRESS_AER_CONTROL;
484	}
 
 
 
 
 
 
 
 
 
 
 
 
 
485
486	requested = control;
487	status = acpi_pci_osc_control_set(handle, &control,
488					  OSC_PCI_EXPRESS_CAPABILITY_CONTROL);
489	if (ACPI_SUCCESS(status)) {
490		decode_osc_control(root, "OS now controls", control);
491		if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_ASPM) {
492			/*
493			 * We have ASPM control, but the FADT indicates that
494			 * it's unsupported. Leave existing configuration
495			 * intact and prevent the OS from touching it.
496			 */
497			dev_info(&device->dev, "FADT indicates ASPM is unsupported, using BIOS configuration\n");
498			*no_aspm = 1;
499		}
500	} else {
501		decode_osc_control(root, "OS requested", requested);
502		decode_osc_control(root, "platform willing to grant", control);
503		dev_info(&device->dev, "_OSC failed (%s); disabling ASPM\n",
504			acpi_format_exception(status));
505
506		/*
507		 * We want to disable ASPM here, but aspm_disabled
508		 * needs to remain in its state from boot so that we
509		 * properly handle PCIe 1.1 devices.  So we set this
510		 * flag here, to defer the action until after the ACPI
511		 * root scan.
512		 */
513		*no_aspm = 1;
514	}
515}
516
517static int acpi_pci_root_add(struct acpi_device *device,
518			     const struct acpi_device_id *not_used)
519{
520	unsigned long long segment, bus;
521	acpi_status status;
522	int result;
523	struct acpi_pci_root *root;
524	acpi_handle handle = device->handle;
525	int no_aspm = 0;
526	bool hotadd = system_state != SYSTEM_BOOTING;
 
527
528	root = kzalloc(sizeof(struct acpi_pci_root), GFP_KERNEL);
529	if (!root)
530		return -ENOMEM;
531
532	segment = 0;
533	status = acpi_evaluate_integer(handle, METHOD_NAME__SEG, NULL,
534				       &segment);
535	if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
536		dev_err(&device->dev,  "can't evaluate _SEG\n");
537		result = -ENODEV;
538		goto end;
539	}
540
541	/* Check _CRS first, then _BBN.  If no _BBN, default to zero. */
542	root->secondary.flags = IORESOURCE_BUS;
543	status = try_get_root_bridge_busnr(handle, &root->secondary);
544	if (ACPI_FAILURE(status)) {
545		/*
546		 * We need both the start and end of the downstream bus range
547		 * to interpret _CBA (MMCONFIG base address), so it really is
548		 * supposed to be in _CRS.  If we don't find it there, all we
549		 * can do is assume [_BBN-0xFF] or [0-0xFF].
550		 */
551		root->secondary.end = 0xFF;
552		dev_warn(&device->dev,
553			 FW_BUG "no secondary bus range in _CRS\n");
554		status = acpi_evaluate_integer(handle, METHOD_NAME__BBN,
555					       NULL, &bus);
556		if (ACPI_SUCCESS(status))
557			root->secondary.start = bus;
558		else if (status == AE_NOT_FOUND)
559			root->secondary.start = 0;
560		else {
561			dev_err(&device->dev, "can't evaluate _BBN\n");
562			result = -ENODEV;
563			goto end;
564		}
565	}
566
567	root->device = device;
568	root->segment = segment & 0xFFFF;
569	strcpy(acpi_device_name(device), ACPI_PCI_ROOT_DEVICE_NAME);
570	strcpy(acpi_device_class(device), ACPI_PCI_ROOT_CLASS);
571	device->driver_data = root;
572
573	if (hotadd && dmar_device_add(handle)) {
574		result = -ENXIO;
575		goto end;
576	}
577
578	pr_info(PREFIX "%s [%s] (domain %04x %pR)\n",
579	       acpi_device_name(device), acpi_device_bid(device),
580	       root->segment, &root->secondary);
581
582	root->mcfg_addr = acpi_pci_root_get_mcfg_addr(handle);
583
584	negotiate_os_control(root, &no_aspm);
 
585
586	/*
587	 * TBD: Need PCI interface for enumeration/configuration of roots.
588	 */
589
590	/*
591	 * Scan the Root Bridge
592	 * --------------------
593	 * Must do this prior to any attempt to bind the root device, as the
594	 * PCI namespace does not get created until this call is made (and
595	 * thus the root bridge's pci_dev does not exist).
596	 */
597	root->bus = pci_acpi_scan_root(root);
598	if (!root->bus) {
599		dev_err(&device->dev,
600			"Bus %04x:%02x not present in PCI namespace\n",
601			root->segment, (unsigned int)root->secondary.start);
602		device->driver_data = NULL;
603		result = -ENODEV;
604		goto remove_dmar;
605	}
606
607	if (no_aspm)
608		pcie_no_aspm();
609
610	pci_acpi_add_bus_pm_notifier(device);
611	if (device->wakeup.flags.run_wake)
612		device_set_run_wake(root->bus->bridge, true);
613
614	if (hotadd) {
615		pcibios_resource_survey_bus(root->bus);
616		pci_assign_unassigned_root_bus_resources(root->bus);
617		/*
618		 * This is only called for the hotadd case. For the boot-time
619		 * case, we need to wait until after PCI initialization in
620		 * order to deal with IOAPICs mapped in on a PCI BAR.
621		 *
622		 * This is currently x86-specific, because acpi_ioapic_add()
623		 * is an empty function without CONFIG_ACPI_HOTPLUG_IOAPIC.
624		 * And CONFIG_ACPI_HOTPLUG_IOAPIC depends on CONFIG_X86_IO_APIC
625		 * (see drivers/acpi/Kconfig).
626		 */
627		acpi_ioapic_add(root->device->handle);
628	}
629
630	pci_lock_rescan_remove();
631	pci_bus_add_devices(root->bus);
632	pci_unlock_rescan_remove();
633	return 1;
634
635remove_dmar:
636	if (hotadd)
637		dmar_device_remove(handle);
638end:
639	kfree(root);
640	return result;
641}
642
643static void acpi_pci_root_remove(struct acpi_device *device)
644{
645	struct acpi_pci_root *root = acpi_driver_data(device);
646
647	pci_lock_rescan_remove();
648
649	pci_stop_root_bus(root->bus);
650
651	WARN_ON(acpi_ioapic_remove(root));
652
653	device_set_run_wake(root->bus->bridge, false);
654	pci_acpi_remove_bus_pm_notifier(device);
655
656	pci_remove_root_bus(root->bus);
 
657
658	dmar_device_remove(device->handle);
659
660	pci_unlock_rescan_remove();
661
662	kfree(root);
663}
664
665/*
666 * Following code to support acpi_pci_root_create() is copied from
667 * arch/x86/pci/acpi.c and modified so it could be reused by x86, IA64
668 * and ARM64.
669 */
670static void acpi_pci_root_validate_resources(struct device *dev,
671					     struct list_head *resources,
672					     unsigned long type)
673{
674	LIST_HEAD(list);
675	struct resource *res1, *res2, *root = NULL;
676	struct resource_entry *tmp, *entry, *entry2;
677
678	BUG_ON((type & (IORESOURCE_MEM | IORESOURCE_IO)) == 0);
679	root = (type & IORESOURCE_MEM) ? &iomem_resource : &ioport_resource;
680
681	list_splice_init(resources, &list);
682	resource_list_for_each_entry_safe(entry, tmp, &list) {
683		bool free = false;
684		resource_size_t end;
685
686		res1 = entry->res;
687		if (!(res1->flags & type))
688			goto next;
689
690		/* Exclude non-addressable range or non-addressable portion */
691		end = min(res1->end, root->end);
692		if (end <= res1->start) {
693			dev_info(dev, "host bridge window %pR (ignored, not CPU addressable)\n",
694				 res1);
695			free = true;
696			goto next;
697		} else if (res1->end != end) {
698			dev_info(dev, "host bridge window %pR ([%#llx-%#llx] ignored, not CPU addressable)\n",
699				 res1, (unsigned long long)end + 1,
700				 (unsigned long long)res1->end);
701			res1->end = end;
702		}
703
704		resource_list_for_each_entry(entry2, resources) {
705			res2 = entry2->res;
706			if (!(res2->flags & type))
707				continue;
708
709			/*
710			 * I don't like throwing away windows because then
711			 * our resources no longer match the ACPI _CRS, but
712			 * the kernel resource tree doesn't allow overlaps.
713			 */
714			if (resource_overlaps(res1, res2)) {
715				res2->start = min(res1->start, res2->start);
716				res2->end = max(res1->end, res2->end);
717				dev_info(dev, "host bridge window expanded to %pR; %pR ignored\n",
718					 res2, res1);
719				free = true;
720				goto next;
721			}
722		}
723
724next:
725		resource_list_del(entry);
726		if (free)
727			resource_list_free_entry(entry);
728		else
729			resource_list_add_tail(entry, resources);
730	}
731}
732
733static void acpi_pci_root_remap_iospace(struct resource_entry *entry)
 
734{
735#ifdef PCI_IOBASE
736	struct resource *res = entry->res;
737	resource_size_t cpu_addr = res->start;
738	resource_size_t pci_addr = cpu_addr - entry->offset;
739	resource_size_t length = resource_size(res);
740	unsigned long port;
741
742	if (pci_register_io_range(cpu_addr, length))
743		goto err;
744
745	port = pci_address_to_pio(cpu_addr);
746	if (port == (unsigned long)-1)
747		goto err;
748
749	res->start = port;
750	res->end = port + length - 1;
751	entry->offset = port - pci_addr;
752
753	if (pci_remap_iospace(res, cpu_addr) < 0)
754		goto err;
755
756	pr_info("Remapped I/O %pa to %pR\n", &cpu_addr, res);
757	return;
758err:
759	res->flags |= IORESOURCE_DISABLED;
760#endif
761}
762
763int acpi_pci_probe_root_resources(struct acpi_pci_root_info *info)
764{
765	int ret;
766	struct list_head *list = &info->resources;
767	struct acpi_device *device = info->bridge;
768	struct resource_entry *entry, *tmp;
769	unsigned long flags;
770
771	flags = IORESOURCE_IO | IORESOURCE_MEM | IORESOURCE_MEM_8AND16BIT;
772	ret = acpi_dev_get_resources(device, list,
773				     acpi_dev_filter_resource_type_cb,
774				     (void *)flags);
775	if (ret < 0)
776		dev_warn(&device->dev,
777			 "failed to parse _CRS method, error code %d\n", ret);
778	else if (ret == 0)
779		dev_dbg(&device->dev,
780			"no IO and memory resources present in _CRS\n");
781	else {
782		resource_list_for_each_entry_safe(entry, tmp, list) {
783			if (entry->res->flags & IORESOURCE_IO)
784				acpi_pci_root_remap_iospace(entry);
 
785
786			if (entry->res->flags & IORESOURCE_DISABLED)
787				resource_list_destroy_entry(entry);
788			else
789				entry->res->name = info->name;
790		}
791		acpi_pci_root_validate_resources(&device->dev, list,
792						 IORESOURCE_MEM);
793		acpi_pci_root_validate_resources(&device->dev, list,
794						 IORESOURCE_IO);
795	}
796
797	return ret;
798}
799
800static void pci_acpi_root_add_resources(struct acpi_pci_root_info *info)
801{
802	struct resource_entry *entry, *tmp;
803	struct resource *res, *conflict, *root = NULL;
804
805	resource_list_for_each_entry_safe(entry, tmp, &info->resources) {
806		res = entry->res;
807		if (res->flags & IORESOURCE_MEM)
808			root = &iomem_resource;
809		else if (res->flags & IORESOURCE_IO)
810			root = &ioport_resource;
811		else
812			continue;
813
814		/*
815		 * Some legacy x86 host bridge drivers use iomem_resource and
816		 * ioport_resource as default resource pool, skip it.
817		 */
818		if (res == root)
819			continue;
820
821		conflict = insert_resource_conflict(root, res);
822		if (conflict) {
823			dev_info(&info->bridge->dev,
824				 "ignoring host bridge window %pR (conflicts with %s %pR)\n",
825				 res, conflict->name, conflict);
826			resource_list_destroy_entry(entry);
827		}
828	}
829}
830
831static void __acpi_pci_root_release_info(struct acpi_pci_root_info *info)
832{
833	struct resource *res;
834	struct resource_entry *entry, *tmp;
835
836	if (!info)
837		return;
838
839	resource_list_for_each_entry_safe(entry, tmp, &info->resources) {
840		res = entry->res;
841		if (res->parent &&
842		    (res->flags & (IORESOURCE_MEM | IORESOURCE_IO)))
843			release_resource(res);
844		resource_list_destroy_entry(entry);
845	}
846
847	info->ops->release_info(info);
848}
849
850static void acpi_pci_root_release_info(struct pci_host_bridge *bridge)
851{
852	struct resource *res;
853	struct resource_entry *entry;
854
855	resource_list_for_each_entry(entry, &bridge->windows) {
856		res = entry->res;
857		if (res->flags & IORESOURCE_IO)
858			pci_unmap_iospace(res);
859		if (res->parent &&
860		    (res->flags & (IORESOURCE_MEM | IORESOURCE_IO)))
861			release_resource(res);
862	}
863	__acpi_pci_root_release_info(bridge->release_data);
864}
865
866struct pci_bus *acpi_pci_root_create(struct acpi_pci_root *root,
867				     struct acpi_pci_root_ops *ops,
868				     struct acpi_pci_root_info *info,
869				     void *sysdata)
870{
871	int ret, busnum = root->secondary.start;
872	struct acpi_device *device = root->device;
873	int node = acpi_get_node(device->handle);
874	struct pci_bus *bus;
 
 
875
876	info->root = root;
877	info->bridge = device;
878	info->ops = ops;
879	INIT_LIST_HEAD(&info->resources);
880	snprintf(info->name, sizeof(info->name), "PCI Bus %04x:%02x",
881		 root->segment, busnum);
882
883	if (ops->init_info && ops->init_info(info))
884		goto out_release_info;
885	if (ops->prepare_resources)
886		ret = ops->prepare_resources(info);
887	else
888		ret = acpi_pci_probe_root_resources(info);
889	if (ret < 0)
890		goto out_release_info;
891
892	pci_acpi_root_add_resources(info);
893	pci_add_resource(&info->resources, &root->secondary);
894	bus = pci_create_root_bus(NULL, busnum, ops->pci_ops,
895				  sysdata, &info->resources);
896	if (!bus)
897		goto out_release_info;
898
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
899	pci_scan_child_bus(bus);
900	pci_set_host_bridge_release(to_pci_host_bridge(bus->bridge),
901				    acpi_pci_root_release_info, info);
902	if (node != NUMA_NO_NODE)
903		dev_printk(KERN_DEBUG, &bus->dev, "on NUMA node %d\n", node);
904	return bus;
905
906out_release_info:
907	__acpi_pci_root_release_info(info);
908	return NULL;
909}
910
911void __init acpi_pci_root_init(void)
912{
913	acpi_hest_init();
914	if (acpi_pci_disabled)
915		return;
916
917	pci_acpi_crs_quirks();
918	acpi_scan_add_handler_with_hotplug(&pci_root_handler, "pci_root");
919}