Linux Audio

Check our new training course

Loading...
v3.5.6
 
  1/*
  2 *  pci_root.c - ACPI PCI Root Bridge Driver ($Revision: 40 $)
  3 *
  4 *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
  5 *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
  6 *
  7 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  8 *
  9 *  This program is free software; you can redistribute it and/or modify
 10 *  it under the terms of the GNU General Public License as published by
 11 *  the Free Software Foundation; either version 2 of the License, or (at
 12 *  your option) any later version.
 13 *
 14 *  This program is distributed in the hope that it will be useful, but
 15 *  WITHOUT ANY WARRANTY; without even the implied warranty of
 16 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 17 *  General Public License for more details.
 18 *
 19 *  You should have received a copy of the GNU General Public License along
 20 *  with this program; if not, write to the Free Software Foundation, Inc.,
 21 *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
 22 *
 23 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 24 */
 25
 
 
 26#include <linux/kernel.h>
 27#include <linux/module.h>
 28#include <linux/init.h>
 29#include <linux/types.h>
 30#include <linux/spinlock.h>
 31#include <linux/pm.h>
 32#include <linux/pm_runtime.h>
 33#include <linux/pci.h>
 34#include <linux/pci-acpi.h>
 35#include <linux/pci-aspm.h>
 36#include <linux/acpi.h>
 37#include <linux/slab.h>
 38#include <acpi/acpi_bus.h>
 39#include <acpi/acpi_drivers.h>
 40#include <acpi/apei.h>
 41
 42#define PREFIX "ACPI: "
 43
 44#define _COMPONENT		ACPI_PCI_COMPONENT
 45ACPI_MODULE_NAME("pci_root");
 46#define ACPI_PCI_ROOT_CLASS		"pci_bridge"
 47#define ACPI_PCI_ROOT_DEVICE_NAME	"PCI Root Bridge"
 48static int acpi_pci_root_add(struct acpi_device *device);
 49static int acpi_pci_root_remove(struct acpi_device *device, int type);
 50static int acpi_pci_root_start(struct acpi_device *device);
 51
 52#define ACPI_PCIE_REQ_SUPPORT (OSC_EXT_PCI_CONFIG_SUPPORT \
 53				| OSC_ACTIVE_STATE_PWR_SUPPORT \
 54				| OSC_CLOCK_PWR_CAPABILITY_SUPPORT \
 55				| OSC_MSI_SUPPORT)
 
 
 
 
 
 
 56
 57static const struct acpi_device_id root_device_ids[] = {
 58	{"PNP0A03", 0},
 59	{"", 0},
 60};
 61MODULE_DEVICE_TABLE(acpi, root_device_ids);
 62
 63static struct acpi_driver acpi_pci_root_driver = {
 64	.name = "pci_root",
 65	.class = ACPI_PCI_ROOT_CLASS,
 66	.ids = root_device_ids,
 67	.ops = {
 68		.add = acpi_pci_root_add,
 69		.remove = acpi_pci_root_remove,
 70		.start = acpi_pci_root_start,
 71		},
 
 72};
 73
 74static LIST_HEAD(acpi_pci_roots);
 75
 76static struct acpi_pci_driver *sub_driver;
 77static DEFINE_MUTEX(osc_lock);
 78
 79int acpi_pci_register_driver(struct acpi_pci_driver *driver)
 80{
 81	int n = 0;
 82	struct acpi_pci_root *root;
 83
 84	struct acpi_pci_driver **pptr = &sub_driver;
 85	while (*pptr)
 86		pptr = &(*pptr)->next;
 87	*pptr = driver;
 88
 89	if (!driver->add)
 90		return 0;
 91
 92	list_for_each_entry(root, &acpi_pci_roots, node) {
 93		driver->add(root->device->handle);
 94		n++;
 95	}
 96
 97	return n;
 98}
 99
100EXPORT_SYMBOL(acpi_pci_register_driver);
101
102void acpi_pci_unregister_driver(struct acpi_pci_driver *driver)
103{
104	struct acpi_pci_root *root;
105
106	struct acpi_pci_driver **pptr = &sub_driver;
107	while (*pptr) {
108		if (*pptr == driver)
109			break;
110		pptr = &(*pptr)->next;
111	}
112	BUG_ON(!*pptr);
113	*pptr = (*pptr)->next;
114
115	if (!driver->remove)
116		return;
117
118	list_for_each_entry(root, &acpi_pci_roots, node)
119		driver->remove(root->device->handle);
120}
121
122EXPORT_SYMBOL(acpi_pci_unregister_driver);
123
124acpi_handle acpi_get_pci_rootbridge_handle(unsigned int seg, unsigned int bus)
125{
126	struct acpi_pci_root *root;
127	
128	list_for_each_entry(root, &acpi_pci_roots, node)
129		if ((root->segment == (u16) seg) &&
130		    (root->secondary.start == (u16) bus))
131			return root->device->handle;
132	return NULL;		
133}
134
135EXPORT_SYMBOL_GPL(acpi_get_pci_rootbridge_handle);
136
137/**
138 * acpi_is_root_bridge - determine whether an ACPI CA node is a PCI root bridge
139 * @handle - the ACPI CA node in question.
140 *
141 * Note: we could make this API take a struct acpi_device * instead, but
142 * for now, it's more convenient to operate on an acpi_handle.
143 */
144int acpi_is_root_bridge(acpi_handle handle)
145{
 
146	int ret;
147	struct acpi_device *device;
148
149	ret = acpi_bus_get_device(handle, &device);
150	if (ret)
151		return 0;
152
153	ret = acpi_match_device_ids(device, root_device_ids);
154	if (ret)
155		return 0;
156	else
157		return 1;
158}
159EXPORT_SYMBOL_GPL(acpi_is_root_bridge);
160
161static acpi_status
162get_root_bridge_busnr_callback(struct acpi_resource *resource, void *data)
163{
164	struct resource *res = data;
165	struct acpi_resource_address64 address;
 
166
167	if (resource->type != ACPI_RESOURCE_TYPE_ADDRESS16 &&
168	    resource->type != ACPI_RESOURCE_TYPE_ADDRESS32 &&
169	    resource->type != ACPI_RESOURCE_TYPE_ADDRESS64)
170		return AE_OK;
171
172	acpi_resource_to_address64(resource, &address);
173	if ((address.address_length > 0) &&
174	    (address.resource_type == ACPI_BUS_NUMBER_RANGE)) {
175		res->start = address.minimum;
176		res->end = address.minimum + address.address_length - 1;
177	}
178
179	return AE_OK;
180}
181
182static acpi_status try_get_root_bridge_busnr(acpi_handle handle,
183					     struct resource *res)
184{
185	acpi_status status;
186
187	res->start = -1;
188	status =
189	    acpi_walk_resources(handle, METHOD_NAME__CRS,
190				get_root_bridge_busnr_callback, res);
191	if (ACPI_FAILURE(status))
192		return status;
193	if (res->start == -1)
194		return AE_ERROR;
195	return AE_OK;
196}
197
198static void acpi_pci_bridge_scan(struct acpi_device *device)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
199{
200	int status;
201	struct acpi_device *child = NULL;
 
202
203	if (device->flags.bus_address)
204		if (device->parent && device->parent->ops.bind) {
205			status = device->parent->ops.bind(device);
206			if (!status) {
207				list_for_each_entry(child, &device->children, node)
208					acpi_pci_bridge_scan(child);
209			}
210		}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
211}
212
213static u8 pci_osc_uuid_str[] = "33DB4D5B-1FF7-401C-9657-7441C03DD766";
 
 
 
 
 
 
 
 
214
215static acpi_status acpi_pci_run_osc(acpi_handle handle,
216				    const u32 *capbuf, u32 *retval)
 
 
 
 
 
 
 
 
217{
218	struct acpi_osc_context context = {
219		.uuid_str = pci_osc_uuid_str,
220		.rev = 1,
221		.cap.length = 12,
222		.cap.pointer = (void *)capbuf,
223	};
224	acpi_status status;
225
226	status = acpi_run_osc(handle, &context);
227	if (ACPI_SUCCESS(status)) {
228		*retval = *((u32 *)(context.ret.pointer + 8));
 
 
229		kfree(context.ret.pointer);
230	}
231	return status;
232}
233
234static acpi_status acpi_pci_query_osc(struct acpi_pci_root *root,
235					u32 support,
236					u32 *control)
237{
238	acpi_status status;
239	u32 result, capbuf[3];
240
241	support &= OSC_PCI_SUPPORT_MASKS;
242	support |= root->osc_support_set;
243
244	capbuf[OSC_QUERY_TYPE] = OSC_QUERY_ENABLE;
245	capbuf[OSC_SUPPORT_TYPE] = support;
246	if (control) {
247		*control &= OSC_PCI_CONTROL_MASKS;
248		capbuf[OSC_CONTROL_TYPE] = *control | root->osc_control_set;
249	} else {
250		/* Run _OSC query for all possible controls. */
251		capbuf[OSC_CONTROL_TYPE] = OSC_PCI_CONTROL_MASKS;
252	}
253
254	status = acpi_pci_run_osc(root->device->handle, capbuf, &result);
 
255	if (ACPI_SUCCESS(status)) {
256		root->osc_support_set = support;
257		if (control)
258			*control = result;
 
 
 
 
 
 
 
 
 
 
259	}
260	return status;
261}
262
263static acpi_status acpi_pci_osc_support(struct acpi_pci_root *root, u32 flags)
264{
265	acpi_status status;
266	acpi_handle tmp;
267
268	status = acpi_get_handle(root->device->handle, "_OSC", &tmp);
269	if (ACPI_FAILURE(status))
270		return status;
271	mutex_lock(&osc_lock);
272	status = acpi_pci_query_osc(root, flags, NULL);
273	mutex_unlock(&osc_lock);
274	return status;
275}
276
277struct acpi_pci_root *acpi_pci_find_root(acpi_handle handle)
278{
 
279	struct acpi_pci_root *root;
280
281	list_for_each_entry(root, &acpi_pci_roots, node) {
282		if (root->device->handle == handle)
283			return root;
284	}
285	return NULL;
 
286}
287EXPORT_SYMBOL_GPL(acpi_pci_find_root);
288
289struct acpi_handle_node {
290	struct list_head node;
291	acpi_handle handle;
292};
293
294/**
295 * acpi_get_pci_dev - convert ACPI CA handle to struct pci_dev
296 * @handle: the handle in question
297 *
298 * Given an ACPI CA handle, the desired PCI device is located in the
299 * list of PCI devices.
300 *
301 * If the device is found, its reference count is increased and this
302 * function returns a pointer to its data structure.  The caller must
303 * decrement the reference count by calling pci_dev_put().
304 * If no device is found, %NULL is returned.
305 */
306struct pci_dev *acpi_get_pci_dev(acpi_handle handle)
307{
308	int dev, fn;
309	unsigned long long adr;
310	acpi_status status;
311	acpi_handle phandle;
312	struct pci_bus *pbus;
313	struct pci_dev *pdev = NULL;
314	struct acpi_handle_node *node, *tmp;
315	struct acpi_pci_root *root;
316	LIST_HEAD(device_list);
317
318	/*
319	 * Walk up the ACPI CA namespace until we reach a PCI root bridge.
320	 */
321	phandle = handle;
322	while (!acpi_is_root_bridge(phandle)) {
323		node = kzalloc(sizeof(struct acpi_handle_node), GFP_KERNEL);
324		if (!node)
325			goto out;
326
327		INIT_LIST_HEAD(&node->node);
328		node->handle = phandle;
329		list_add(&node->node, &device_list);
330
331		status = acpi_get_parent(phandle, &phandle);
332		if (ACPI_FAILURE(status))
333			goto out;
334	}
335
336	root = acpi_pci_find_root(phandle);
337	if (!root)
338		goto out;
339
340	pbus = root->bus;
341
342	/*
343	 * Now, walk back down the PCI device tree until we return to our
344	 * original handle. Assumes that everything between the PCI root
345	 * bridge and the device we're looking for must be a P2P bridge.
346	 */
347	list_for_each_entry(node, &device_list, node) {
348		acpi_handle hnd = node->handle;
349		status = acpi_evaluate_integer(hnd, "_ADR", NULL, &adr);
350		if (ACPI_FAILURE(status))
351			goto out;
352		dev = (adr >> 16) & 0xffff;
353		fn  = adr & 0xffff;
354
355		pdev = pci_get_slot(pbus, PCI_DEVFN(dev, fn));
356		if (!pdev || hnd == handle)
357			break;
358
359		pbus = pdev->subordinate;
360		pci_dev_put(pdev);
361
362		/*
363		 * This function may be called for a non-PCI device that has a
364		 * PCI parent (eg. a disk under a PCI SATA controller).  In that
365		 * case pdev->subordinate will be NULL for the parent.
366		 */
367		if (!pbus) {
368			dev_dbg(&pdev->dev, "Not a PCI-to-PCI bridge\n");
369			pdev = NULL;
370			break;
371		}
372	}
373out:
374	list_for_each_entry_safe(node, tmp, &device_list, node)
375		kfree(node);
376
377	return pdev;
 
 
378}
379EXPORT_SYMBOL_GPL(acpi_get_pci_dev);
380
381/**
382 * acpi_pci_osc_control_set - Request control of PCI root _OSC features.
383 * @handle: ACPI handle of a PCI root bridge (or PCIe Root Complex).
384 * @mask: Mask of _OSC bits to request control of, place to store control mask.
385 * @req: Mask of _OSC bits the control of is essential to the caller.
 
 
386 *
387 * Run _OSC query for @mask and if that is successful, compare the returned
388 * mask of control bits with @req.  If all of the @req bits are set in the
389 * returned mask, run _OSC request for it.
390 *
391 * The variable at the @mask address may be modified regardless of whether or
392 * not the function returns success.  On success it will contain the mask of
393 * _OSC bits the BIOS has granted control of, but its contents are meaningless
394 * on failure.
395 **/
396acpi_status acpi_pci_osc_control_set(acpi_handle handle, u32 *mask, u32 req)
 
 
397{
 
398	struct acpi_pci_root *root;
399	acpi_status status;
400	u32 ctrl, capbuf[3];
401	acpi_handle tmp;
402
403	if (!mask)
404		return AE_BAD_PARAMETER;
405
406	ctrl = *mask & OSC_PCI_CONTROL_MASKS;
407	if ((ctrl & req) != req)
408		return AE_TYPE;
409
410	root = acpi_pci_find_root(handle);
411	if (!root)
412		return AE_NOT_EXIST;
413
414	status = acpi_get_handle(handle, "_OSC", &tmp);
415	if (ACPI_FAILURE(status))
416		return status;
417
418	mutex_lock(&osc_lock);
419
420	*mask = ctrl | root->osc_control_set;
421	/* No need to evaluate _OSC if the control was already granted. */
422	if ((root->osc_control_set & ctrl) == ctrl)
423		goto out;
424
425	/* Need to check the available controls bits before requesting them. */
426	while (*mask) {
427		status = acpi_pci_query_osc(root, root->osc_support_set, mask);
 
 
 
428		if (ACPI_FAILURE(status))
429			goto out;
430		if (ctrl == *mask)
431			break;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
432		ctrl = *mask;
433	}
 
 
 
 
 
 
434
435	if ((ctrl & req) != req) {
436		status = AE_SUPPORT;
437		goto out;
 
438	}
439
440	capbuf[OSC_QUERY_TYPE] = 0;
441	capbuf[OSC_SUPPORT_TYPE] = root->osc_support_set;
442	capbuf[OSC_CONTROL_TYPE] = ctrl;
443	status = acpi_pci_run_osc(handle, capbuf, mask);
444	if (ACPI_SUCCESS(status))
445		root->osc_control_set = *mask;
446out:
447	mutex_unlock(&osc_lock);
448	return status;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
449}
450EXPORT_SYMBOL(acpi_pci_osc_control_set);
451
452static int __devinit acpi_pci_root_add(struct acpi_device *device)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
453{
454	unsigned long long segment, bus;
455	acpi_status status;
456	int result;
457	struct acpi_pci_root *root;
458	acpi_handle handle;
459	struct acpi_device *child;
460	u32 flags, base_flags;
 
461
462	root = kzalloc(sizeof(struct acpi_pci_root), GFP_KERNEL);
463	if (!root)
464		return -ENOMEM;
465
466	segment = 0;
467	status = acpi_evaluate_integer(device->handle, METHOD_NAME__SEG, NULL,
468				       &segment);
469	if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
470		printk(KERN_ERR PREFIX "can't evaluate _SEG\n");
471		result = -ENODEV;
472		goto end;
473	}
474
475	/* Check _CRS first, then _BBN.  If no _BBN, default to zero. */
476	root->secondary.flags = IORESOURCE_BUS;
477	status = try_get_root_bridge_busnr(device->handle, &root->secondary);
478	if (ACPI_FAILURE(status)) {
479		/*
480		 * We need both the start and end of the downstream bus range
481		 * to interpret _CBA (MMCONFIG base address), so it really is
482		 * supposed to be in _CRS.  If we don't find it there, all we
483		 * can do is assume [_BBN-0xFF] or [0-0xFF].
484		 */
485		root->secondary.end = 0xFF;
486		printk(KERN_WARNING FW_BUG PREFIX
487		       "no secondary bus range in _CRS\n");
488		status = acpi_evaluate_integer(device->handle, METHOD_NAME__BBN,
489					       NULL, &bus);
490		if (ACPI_SUCCESS(status))
491			root->secondary.start = bus;
492		else if (status == AE_NOT_FOUND)
493			root->secondary.start = 0;
494		else {
495			printk(KERN_ERR PREFIX "can't evaluate _BBN\n");
496			result = -ENODEV;
497			goto end;
498		}
499	}
500
501	INIT_LIST_HEAD(&root->node);
502	root->device = device;
503	root->segment = segment & 0xFFFF;
504	strcpy(acpi_device_name(device), ACPI_PCI_ROOT_DEVICE_NAME);
505	strcpy(acpi_device_class(device), ACPI_PCI_ROOT_CLASS);
506	device->driver_data = root;
507
508	/*
509	 * All supported architectures that use ACPI have support for
510	 * PCI domains, so we indicate this in _OSC support capabilities.
511	 */
512	flags = base_flags = OSC_PCI_SEGMENT_GROUPS_SUPPORT;
513	acpi_pci_osc_support(root, flags);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
514
515	/*
516	 * TBD: Need PCI interface for enumeration/configuration of roots.
517	 */
518
519	/* TBD: Locking */
520	list_add_tail(&root->node, &acpi_pci_roots);
521
522	printk(KERN_INFO PREFIX "%s [%s] (domain %04x %pR)\n",
523	       acpi_device_name(device), acpi_device_bid(device),
524	       root->segment, &root->secondary);
525
526	/*
527	 * Scan the Root Bridge
528	 * --------------------
529	 * Must do this prior to any attempt to bind the root device, as the
530	 * PCI namespace does not get created until this call is made (and 
531	 * thus the root bridge's pci_dev does not exist).
532	 */
533	root->bus = pci_acpi_scan_root(root);
534	if (!root->bus) {
535		printk(KERN_ERR PREFIX
536			    "Bus %04x:%02x not present in PCI namespace\n",
537			    root->segment, (unsigned int)root->secondary.start);
 
538		result = -ENODEV;
539		goto end;
540	}
541
542	/*
543	 * Attach ACPI-PCI Context
544	 * -----------------------
545	 * Thus binding the ACPI and PCI devices.
546	 */
547	result = acpi_pci_bind_root(device);
548	if (result)
549		goto end;
550
551	/*
552	 * PCI Routing Table
553	 * -----------------
554	 * Evaluate and parse _PRT, if exists.
555	 */
556	status = acpi_get_handle(device->handle, METHOD_NAME__PRT, &handle);
557	if (ACPI_SUCCESS(status))
558		result = acpi_pci_irq_add_prt(device->handle, root->bus);
559
560	/*
561	 * Scan and bind all _ADR-Based Devices
562	 */
563	list_for_each_entry(child, &device->children, node)
564		acpi_pci_bridge_scan(child);
 
 
 
 
 
 
 
 
 
 
565
566	/* Indicate support for various _OSC capabilities. */
567	if (pci_ext_cfg_avail(root->bus->self))
568		flags |= OSC_EXT_PCI_CONFIG_SUPPORT;
569	if (pcie_aspm_support_enabled())
570		flags |= OSC_ACTIVE_STATE_PWR_SUPPORT |
571			OSC_CLOCK_PWR_CAPABILITY_SUPPORT;
572	if (pci_msi_enabled())
573		flags |= OSC_MSI_SUPPORT;
574	if (flags != base_flags)
575		acpi_pci_osc_support(root, flags);
576
577	if (!pcie_ports_disabled
578	    && (flags & ACPI_PCIE_REQ_SUPPORT) == ACPI_PCIE_REQ_SUPPORT) {
579		flags = OSC_PCI_EXPRESS_CAP_STRUCTURE_CONTROL
580			| OSC_PCI_EXPRESS_NATIVE_HP_CONTROL
581			| OSC_PCI_EXPRESS_PME_CONTROL;
582
583		if (pci_aer_available()) {
584			if (aer_acpi_firmware_first())
585				dev_dbg(root->bus->bridge,
586					"PCIe errors handled by BIOS.\n");
587			else
588				flags |= OSC_PCI_EXPRESS_AER_CONTROL;
589		}
 
 
 
590
591		dev_info(root->bus->bridge,
592			"Requesting ACPI _OSC control (0x%02x)\n", flags);
593
594		status = acpi_pci_osc_control_set(device->handle, &flags,
595					OSC_PCI_EXPRESS_CAP_STRUCTURE_CONTROL);
596		if (ACPI_SUCCESS(status)) {
597			dev_info(root->bus->bridge,
598				"ACPI _OSC control (0x%02x) granted\n", flags);
599			if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_ASPM) {
600				/*
601				 * We have ASPM control, but the FADT indicates
602				 * that it's unsupported. Clear it.
603				 */
604				pcie_clear_aspm(root->bus);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
605			}
606		} else {
607			dev_info(root->bus->bridge,
608				"ACPI _OSC request failed (%s), "
609				"returned control mask: 0x%02x\n",
610				acpi_format_exception(status), flags);
611			pr_info("ACPI _OSC control for PCIe not granted, "
612				"disabling ASPM\n");
613			pcie_no_aspm();
614		}
615	} else {
616		dev_info(root->bus->bridge,
617			 "Unable to request _OSC control "
618			 "(_OSC support mask: 0x%02x)\n", flags);
 
 
 
619	}
 
620
621	pci_acpi_add_bus_pm_notifier(device, root->bus);
622	if (device->wakeup.flags.run_wake)
623		device_set_run_wake(root->bus->bridge, true);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
624
625	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
626
627end:
628	if (!list_empty(&root->node))
629		list_del(&root->node);
630	kfree(root);
631	return result;
 
 
 
 
 
 
 
632}
633
634static int acpi_pci_root_start(struct acpi_device *device)
635{
636	struct acpi_pci_root *root = acpi_driver_data(device);
 
637
638	pci_bus_add_devices(root->bus);
639	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
640}
641
642static int acpi_pci_root_remove(struct acpi_device *device, int type)
643{
644	struct acpi_pci_root *root = acpi_driver_data(device);
 
645
646	device_set_run_wake(root->bus->bridge, false);
647	pci_acpi_remove_bus_pm_notifier(device);
648
649	kfree(root);
650	return 0;
 
 
 
 
 
 
 
651}
652
653static int __init acpi_pci_root_init(void)
654{
655	acpi_hest_init();
 
656
657	if (acpi_pci_disabled)
658		return 0;
 
 
 
 
 
 
 
 
659
660	pci_acpi_crs_quirks();
661	if (acpi_bus_register_driver(&acpi_pci_root_driver) < 0)
662		return -ENODEV;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
663
664	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
665}
666
667subsys_initcall(acpi_pci_root_init);
 
 
 
 
 
 
 
v6.2
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 *  pci_root.c - ACPI PCI Root Bridge Driver ($Revision: 40 $)
   4 *
   5 *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
   6 *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
   7 */
   8
   9#define pr_fmt(fmt) "ACPI: " fmt
  10
  11#include <linux/kernel.h>
  12#include <linux/module.h>
  13#include <linux/init.h>
  14#include <linux/types.h>
  15#include <linux/mutex.h>
  16#include <linux/pm.h>
  17#include <linux/pm_runtime.h>
  18#include <linux/pci.h>
  19#include <linux/pci-acpi.h>
  20#include <linux/dmar.h>
  21#include <linux/acpi.h>
  22#include <linux/slab.h>
  23#include <linux/dmi.h>
  24#include <linux/platform_data/x86/apple.h>
  25#include "internal.h"
 
 
  26
 
 
  27#define ACPI_PCI_ROOT_CLASS		"pci_bridge"
  28#define ACPI_PCI_ROOT_DEVICE_NAME	"PCI Root Bridge"
  29static int acpi_pci_root_add(struct acpi_device *device,
  30			     const struct acpi_device_id *not_used);
  31static void acpi_pci_root_remove(struct acpi_device *device);
  32
  33static int acpi_pci_root_scan_dependent(struct acpi_device *adev)
  34{
  35	acpiphp_check_host_bridge(adev);
  36	return 0;
  37}
  38
  39#define ACPI_PCIE_REQ_SUPPORT (OSC_PCI_EXT_CONFIG_SUPPORT \
  40				| OSC_PCI_ASPM_SUPPORT \
  41				| OSC_PCI_CLOCK_PM_SUPPORT \
  42				| OSC_PCI_MSI_SUPPORT)
  43
  44static const struct acpi_device_id root_device_ids[] = {
  45	{"PNP0A03", 0},
  46	{"", 0},
  47};
 
  48
  49static struct acpi_scan_handler pci_root_handler = {
 
 
  50	.ids = root_device_ids,
  51	.attach = acpi_pci_root_add,
  52	.detach = acpi_pci_root_remove,
  53	.hotplug = {
  54		.enabled = true,
  55		.scan_dependent = acpi_pci_root_scan_dependent,
  56	},
  57};
  58
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  59/**
  60 * acpi_is_root_bridge - determine whether an ACPI CA node is a PCI root bridge
  61 * @handle:  the ACPI CA node in question.
  62 *
  63 * Note: we could make this API take a struct acpi_device * instead, but
  64 * for now, it's more convenient to operate on an acpi_handle.
  65 */
  66int acpi_is_root_bridge(acpi_handle handle)
  67{
  68	struct acpi_device *device = acpi_fetch_acpi_dev(handle);
  69	int ret;
 
  70
  71	if (!device)
 
  72		return 0;
  73
  74	ret = acpi_match_device_ids(device, root_device_ids);
  75	if (ret)
  76		return 0;
  77	else
  78		return 1;
  79}
  80EXPORT_SYMBOL_GPL(acpi_is_root_bridge);
  81
  82static acpi_status
  83get_root_bridge_busnr_callback(struct acpi_resource *resource, void *data)
  84{
  85	struct resource *res = data;
  86	struct acpi_resource_address64 address;
  87	acpi_status status;
  88
  89	status = acpi_resource_to_address64(resource, &address);
  90	if (ACPI_FAILURE(status))
 
  91		return AE_OK;
  92
  93	if ((address.address.address_length > 0) &&
 
  94	    (address.resource_type == ACPI_BUS_NUMBER_RANGE)) {
  95		res->start = address.address.minimum;
  96		res->end = address.address.minimum + address.address.address_length - 1;
  97	}
  98
  99	return AE_OK;
 100}
 101
 102static acpi_status try_get_root_bridge_busnr(acpi_handle handle,
 103					     struct resource *res)
 104{
 105	acpi_status status;
 106
 107	res->start = -1;
 108	status =
 109	    acpi_walk_resources(handle, METHOD_NAME__CRS,
 110				get_root_bridge_busnr_callback, res);
 111	if (ACPI_FAILURE(status))
 112		return status;
 113	if (res->start == -1)
 114		return AE_ERROR;
 115	return AE_OK;
 116}
 117
 118struct pci_osc_bit_struct {
 119	u32 bit;
 120	char *desc;
 121};
 122
 123static struct pci_osc_bit_struct pci_osc_support_bit[] = {
 124	{ OSC_PCI_EXT_CONFIG_SUPPORT, "ExtendedConfig" },
 125	{ OSC_PCI_ASPM_SUPPORT, "ASPM" },
 126	{ OSC_PCI_CLOCK_PM_SUPPORT, "ClockPM" },
 127	{ OSC_PCI_SEGMENT_GROUPS_SUPPORT, "Segments" },
 128	{ OSC_PCI_MSI_SUPPORT, "MSI" },
 129	{ OSC_PCI_EDR_SUPPORT, "EDR" },
 130	{ OSC_PCI_HPX_TYPE_3_SUPPORT, "HPX-Type3" },
 131};
 132
 133static struct pci_osc_bit_struct pci_osc_control_bit[] = {
 134	{ OSC_PCI_EXPRESS_NATIVE_HP_CONTROL, "PCIeHotplug" },
 135	{ OSC_PCI_SHPC_NATIVE_HP_CONTROL, "SHPCHotplug" },
 136	{ OSC_PCI_EXPRESS_PME_CONTROL, "PME" },
 137	{ OSC_PCI_EXPRESS_AER_CONTROL, "AER" },
 138	{ OSC_PCI_EXPRESS_CAPABILITY_CONTROL, "PCIeCapability" },
 139	{ OSC_PCI_EXPRESS_LTR_CONTROL, "LTR" },
 140	{ OSC_PCI_EXPRESS_DPC_CONTROL, "DPC" },
 141};
 142
 143static struct pci_osc_bit_struct cxl_osc_support_bit[] = {
 144	{ OSC_CXL_1_1_PORT_REG_ACCESS_SUPPORT, "CXL11PortRegAccess" },
 145	{ OSC_CXL_2_0_PORT_DEV_REG_ACCESS_SUPPORT, "CXL20PortDevRegAccess" },
 146	{ OSC_CXL_PROTOCOL_ERR_REPORTING_SUPPORT, "CXLProtocolErrorReporting" },
 147	{ OSC_CXL_NATIVE_HP_SUPPORT, "CXLNativeHotPlug" },
 148};
 149
 150static struct pci_osc_bit_struct cxl_osc_control_bit[] = {
 151	{ OSC_CXL_ERROR_REPORTING_CONTROL, "CXLMemErrorReporting" },
 152};
 153
 154static void decode_osc_bits(struct acpi_pci_root *root, char *msg, u32 word,
 155			    struct pci_osc_bit_struct *table, int size)
 156{
 157	char buf[80];
 158	int i, len = 0;
 159	struct pci_osc_bit_struct *entry;
 160
 161	buf[0] = '\0';
 162	for (i = 0, entry = table; i < size; i++, entry++)
 163		if (word & entry->bit)
 164			len += scnprintf(buf + len, sizeof(buf) - len, "%s%s",
 165					len ? " " : "", entry->desc);
 166
 167	dev_info(&root->device->dev, "_OSC: %s [%s]\n", msg, buf);
 168}
 169
 170static void decode_osc_support(struct acpi_pci_root *root, char *msg, u32 word)
 171{
 172	decode_osc_bits(root, msg, word, pci_osc_support_bit,
 173			ARRAY_SIZE(pci_osc_support_bit));
 174}
 175
 176static void decode_osc_control(struct acpi_pci_root *root, char *msg, u32 word)
 177{
 178	decode_osc_bits(root, msg, word, pci_osc_control_bit,
 179			ARRAY_SIZE(pci_osc_control_bit));
 180}
 181
 182static void decode_cxl_osc_support(struct acpi_pci_root *root, char *msg, u32 word)
 183{
 184	decode_osc_bits(root, msg, word, cxl_osc_support_bit,
 185			ARRAY_SIZE(cxl_osc_support_bit));
 186}
 187
 188static void decode_cxl_osc_control(struct acpi_pci_root *root, char *msg, u32 word)
 189{
 190	decode_osc_bits(root, msg, word, cxl_osc_control_bit,
 191			ARRAY_SIZE(cxl_osc_control_bit));
 192}
 193
 194static inline bool is_pcie(struct acpi_pci_root *root)
 195{
 196	return root->bridge_type == ACPI_BRIDGE_TYPE_PCIE;
 197}
 198
 199static inline bool is_cxl(struct acpi_pci_root *root)
 200{
 201	return root->bridge_type == ACPI_BRIDGE_TYPE_CXL;
 202}
 203
 204static u8 pci_osc_uuid_str[] = "33DB4D5B-1FF7-401C-9657-7441C03DD766";
 205static u8 cxl_osc_uuid_str[] = "68F2D50B-C469-4d8A-BD3D-941A103FD3FC";
 206
 207static char *to_uuid(struct acpi_pci_root *root)
 208{
 209	if (is_cxl(root))
 210		return cxl_osc_uuid_str;
 211	return pci_osc_uuid_str;
 212}
 213
 214static int cap_length(struct acpi_pci_root *root)
 215{
 216	if (is_cxl(root))
 217		return sizeof(u32) * OSC_CXL_CAPABILITY_DWORDS;
 218	return sizeof(u32) * OSC_PCI_CAPABILITY_DWORDS;
 219}
 220
 221static acpi_status acpi_pci_run_osc(struct acpi_pci_root *root,
 222				    const u32 *capbuf, u32 *pci_control,
 223				    u32 *cxl_control)
 224{
 225	struct acpi_osc_context context = {
 226		.uuid_str = to_uuid(root),
 227		.rev = 1,
 228		.cap.length = cap_length(root),
 229		.cap.pointer = (void *)capbuf,
 230	};
 231	acpi_status status;
 232
 233	status = acpi_run_osc(root->device->handle, &context);
 234	if (ACPI_SUCCESS(status)) {
 235		*pci_control = acpi_osc_ctx_get_pci_control(&context);
 236		if (is_cxl(root))
 237			*cxl_control = acpi_osc_ctx_get_cxl_control(&context);
 238		kfree(context.ret.pointer);
 239	}
 240	return status;
 241}
 242
 243static acpi_status acpi_pci_query_osc(struct acpi_pci_root *root, u32 support,
 244				      u32 *control, u32 cxl_support,
 245				      u32 *cxl_control)
 246{
 247	acpi_status status;
 248	u32 pci_result, cxl_result, capbuf[OSC_CXL_CAPABILITY_DWORDS];
 249
 
 250	support |= root->osc_support_set;
 251
 252	capbuf[OSC_QUERY_DWORD] = OSC_QUERY_ENABLE;
 253	capbuf[OSC_SUPPORT_DWORD] = support;
 254	capbuf[OSC_CONTROL_DWORD] = *control | root->osc_control_set;
 255
 256	if (is_cxl(root)) {
 257		cxl_support |= root->osc_ext_support_set;
 258		capbuf[OSC_EXT_SUPPORT_DWORD] = cxl_support;
 259		capbuf[OSC_EXT_CONTROL_DWORD] = *cxl_control | root->osc_ext_control_set;
 260	}
 261
 262retry:
 263	status = acpi_pci_run_osc(root, capbuf, &pci_result, &cxl_result);
 264	if (ACPI_SUCCESS(status)) {
 265		root->osc_support_set = support;
 266		*control = pci_result;
 267		if (is_cxl(root)) {
 268			root->osc_ext_support_set = cxl_support;
 269			*cxl_control = cxl_result;
 270		}
 271	} else if (is_cxl(root)) {
 272		/*
 273		 * CXL _OSC is optional on CXL 1.1 hosts. Fall back to PCIe _OSC
 274		 * upon any failure using CXL _OSC.
 275		 */
 276		root->bridge_type = ACPI_BRIDGE_TYPE_PCIE;
 277		goto retry;
 278	}
 279	return status;
 280}
 281
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 282struct acpi_pci_root *acpi_pci_find_root(acpi_handle handle)
 283{
 284	struct acpi_device *device = acpi_fetch_acpi_dev(handle);
 285	struct acpi_pci_root *root;
 286
 287	if (!device || acpi_match_device_ids(device, root_device_ids))
 288		return NULL;
 289
 290	root = acpi_driver_data(device);
 291
 292	return root;
 293}
 294EXPORT_SYMBOL_GPL(acpi_pci_find_root);
 295
 296struct acpi_handle_node {
 297	struct list_head node;
 298	acpi_handle handle;
 299};
 300
 301/**
 302 * acpi_get_pci_dev - convert ACPI CA handle to struct pci_dev
 303 * @handle: the handle in question
 304 *
 305 * Given an ACPI CA handle, the desired PCI device is located in the
 306 * list of PCI devices.
 307 *
 308 * If the device is found, its reference count is increased and this
 309 * function returns a pointer to its data structure.  The caller must
 310 * decrement the reference count by calling pci_dev_put().
 311 * If no device is found, %NULL is returned.
 312 */
 313struct pci_dev *acpi_get_pci_dev(acpi_handle handle)
 314{
 315	struct acpi_device *adev = acpi_fetch_acpi_dev(handle);
 316	struct acpi_device_physical_node *pn;
 317	struct pci_dev *pci_dev = NULL;
 318
 319	if (!adev)
 320		return NULL;
 321
 322	mutex_lock(&adev->physical_node_lock);
 323
 324	list_for_each_entry(pn, &adev->physical_node_list, node) {
 325		if (dev_is_pci(pn->dev)) {
 326			get_device(pn->dev);
 327			pci_dev = to_pci_dev(pn->dev);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 328			break;
 329		}
 330	}
 
 
 
 331
 332	mutex_unlock(&adev->physical_node_lock);
 333
 334	return pci_dev;
 335}
 336EXPORT_SYMBOL_GPL(acpi_get_pci_dev);
 337
 338/**
 339 * acpi_pci_osc_control_set - Request control of PCI root _OSC features.
 340 * @handle: ACPI handle of a PCI root bridge (or PCIe Root Complex).
 341 * @mask: Mask of _OSC bits to request control of, place to store control mask.
 342 * @support: _OSC supported capability.
 343 * @cxl_mask: Mask of CXL _OSC control bits, place to store control mask.
 344 * @cxl_support: CXL _OSC supported capability.
 345 *
 346 * Run _OSC query for @mask and if that is successful, compare the returned
 347 * mask of control bits with @req.  If all of the @req bits are set in the
 348 * returned mask, run _OSC request for it.
 349 *
 350 * The variable at the @mask address may be modified regardless of whether or
 351 * not the function returns success.  On success it will contain the mask of
 352 * _OSC bits the BIOS has granted control of, but its contents are meaningless
 353 * on failure.
 354 **/
 355static acpi_status acpi_pci_osc_control_set(acpi_handle handle, u32 *mask,
 356					    u32 support, u32 *cxl_mask,
 357					    u32 cxl_support)
 358{
 359	u32 req = OSC_PCI_EXPRESS_CAPABILITY_CONTROL;
 360	struct acpi_pci_root *root;
 361	acpi_status status;
 362	u32 ctrl, cxl_ctrl = 0, capbuf[OSC_CXL_CAPABILITY_DWORDS];
 
 363
 364	if (!mask)
 365		return AE_BAD_PARAMETER;
 366
 
 
 
 
 367	root = acpi_pci_find_root(handle);
 368	if (!root)
 369		return AE_NOT_EXIST;
 370
 371	ctrl   = *mask;
 372	*mask |= root->osc_control_set;
 
 
 
 373
 374	if (is_cxl(root)) {
 375		cxl_ctrl = *cxl_mask;
 376		*cxl_mask |= root->osc_ext_control_set;
 377	}
 378
 379	/* Need to check the available controls bits before requesting them. */
 380	do {
 381		u32 pci_missing = 0, cxl_missing = 0;
 382
 383		status = acpi_pci_query_osc(root, support, mask, cxl_support,
 384					    cxl_mask);
 385		if (ACPI_FAILURE(status))
 386			return status;
 387		if (is_cxl(root)) {
 388			if (ctrl == *mask && cxl_ctrl == *cxl_mask)
 389				break;
 390			pci_missing = ctrl & ~(*mask);
 391			cxl_missing = cxl_ctrl & ~(*cxl_mask);
 392		} else {
 393			if (ctrl == *mask)
 394				break;
 395			pci_missing = ctrl & ~(*mask);
 396		}
 397		if (pci_missing)
 398			decode_osc_control(root, "platform does not support",
 399					   pci_missing);
 400		if (cxl_missing)
 401			decode_cxl_osc_control(root, "CXL platform does not support",
 402					   cxl_missing);
 403		ctrl = *mask;
 404		cxl_ctrl = *cxl_mask;
 405	} while (*mask || *cxl_mask);
 406
 407	/* No need to request _OSC if the control was already granted. */
 408	if ((root->osc_control_set & ctrl) == ctrl &&
 409	    (root->osc_ext_control_set & cxl_ctrl) == cxl_ctrl)
 410		return AE_OK;
 411
 412	if ((ctrl & req) != req) {
 413		decode_osc_control(root, "not requesting control; platform does not support",
 414				   req & ~(ctrl));
 415		return AE_SUPPORT;
 416	}
 417
 418	capbuf[OSC_QUERY_DWORD] = 0;
 419	capbuf[OSC_SUPPORT_DWORD] = root->osc_support_set;
 420	capbuf[OSC_CONTROL_DWORD] = ctrl;
 421	if (is_cxl(root)) {
 422		capbuf[OSC_EXT_SUPPORT_DWORD] = root->osc_ext_support_set;
 423		capbuf[OSC_EXT_CONTROL_DWORD] = cxl_ctrl;
 424	}
 425
 426	status = acpi_pci_run_osc(root, capbuf, mask, cxl_mask);
 427	if (ACPI_FAILURE(status))
 428		return status;
 429
 430	root->osc_control_set = *mask;
 431	root->osc_ext_control_set = *cxl_mask;
 432	return AE_OK;
 433}
 434
 435static u32 calculate_support(void)
 436{
 437	u32 support;
 438
 439	/*
 440	 * All supported architectures that use ACPI have support for
 441	 * PCI domains, so we indicate this in _OSC support capabilities.
 442	 */
 443	support = OSC_PCI_SEGMENT_GROUPS_SUPPORT;
 444	support |= OSC_PCI_HPX_TYPE_3_SUPPORT;
 445	if (pci_ext_cfg_avail())
 446		support |= OSC_PCI_EXT_CONFIG_SUPPORT;
 447	if (pcie_aspm_support_enabled())
 448		support |= OSC_PCI_ASPM_SUPPORT | OSC_PCI_CLOCK_PM_SUPPORT;
 449	if (pci_msi_enabled())
 450		support |= OSC_PCI_MSI_SUPPORT;
 451	if (IS_ENABLED(CONFIG_PCIE_EDR))
 452		support |= OSC_PCI_EDR_SUPPORT;
 453
 454	return support;
 455}
 456
 457/*
 458 * Background on hotplug support, and making it depend on only
 459 * CONFIG_HOTPLUG_PCI_PCIE vs. also considering CONFIG_MEMORY_HOTPLUG:
 460 *
 461 * CONFIG_ACPI_HOTPLUG_MEMORY does depend on CONFIG_MEMORY_HOTPLUG, but
 462 * there is no existing _OSC for memory hotplug support. The reason is that
 463 * ACPI memory hotplug requires the OS to acknowledge / coordinate with
 464 * memory plug events via a scan handler. On the CXL side the equivalent
 465 * would be if Linux supported the Mechanical Retention Lock [1], or
 466 * otherwise had some coordination for the driver of a PCI device
 467 * undergoing hotplug to be consulted on whether the hotplug should
 468 * proceed or not.
 469 *
 470 * The concern is that if Linux says no to supporting CXL hotplug then
 471 * the BIOS may say no to giving the OS hotplug control of any other PCIe
 472 * device. So the question here is not whether hotplug is enabled, it's
 473 * whether it is handled natively by the at all OS, and if
 474 * CONFIG_HOTPLUG_PCI_PCIE is enabled then the answer is "yes".
 475 *
 476 * Otherwise, the plan for CXL coordinated remove, since the kernel does
 477 * not support blocking hotplug, is to require the memory device to be
 478 * disabled before hotplug is attempted. When CONFIG_MEMORY_HOTPLUG is
 479 * disabled that step will fail and the remove attempt cancelled by the
 480 * user. If that is not honored and the card is removed anyway then it
 481 * does not matter if CONFIG_MEMORY_HOTPLUG is enabled or not, it will
 482 * cause a crash and other badness.
 483 *
 484 * Therefore, just say yes to CXL hotplug and require removal to
 485 * be coordinated by userspace unless and until the kernel grows better
 486 * mechanisms for doing "managed" removal of devices in consultation with
 487 * the driver.
 488 *
 489 * [1]: https://lore.kernel.org/all/20201122014203.4706-1-ashok.raj@intel.com/
 490 */
 491static u32 calculate_cxl_support(void)
 492{
 493	u32 support;
 494
 495	support = OSC_CXL_2_0_PORT_DEV_REG_ACCESS_SUPPORT;
 496	support |= OSC_CXL_1_1_PORT_REG_ACCESS_SUPPORT;
 497	if (pci_aer_available())
 498		support |= OSC_CXL_PROTOCOL_ERR_REPORTING_SUPPORT;
 499	if (IS_ENABLED(CONFIG_HOTPLUG_PCI_PCIE))
 500		support |= OSC_CXL_NATIVE_HP_SUPPORT;
 501
 502	return support;
 503}
 504
 505static u32 calculate_control(void)
 506{
 507	u32 control;
 508
 509	control = OSC_PCI_EXPRESS_CAPABILITY_CONTROL
 510		| OSC_PCI_EXPRESS_PME_CONTROL;
 511
 512	if (IS_ENABLED(CONFIG_PCIEASPM))
 513		control |= OSC_PCI_EXPRESS_LTR_CONTROL;
 514
 515	if (IS_ENABLED(CONFIG_HOTPLUG_PCI_PCIE))
 516		control |= OSC_PCI_EXPRESS_NATIVE_HP_CONTROL;
 517
 518	if (IS_ENABLED(CONFIG_HOTPLUG_PCI_SHPC))
 519		control |= OSC_PCI_SHPC_NATIVE_HP_CONTROL;
 520
 521	if (pci_aer_available())
 522		control |= OSC_PCI_EXPRESS_AER_CONTROL;
 523
 524	/*
 525	 * Per the Downstream Port Containment Related Enhancements ECN to
 526	 * the PCI Firmware Spec, r3.2, sec 4.5.1, table 4-5,
 527	 * OSC_PCI_EXPRESS_DPC_CONTROL indicates the OS supports both DPC
 528	 * and EDR.
 529	 */
 530	if (IS_ENABLED(CONFIG_PCIE_DPC) && IS_ENABLED(CONFIG_PCIE_EDR))
 531		control |= OSC_PCI_EXPRESS_DPC_CONTROL;
 532
 533	return control;
 534}
 535
 536static u32 calculate_cxl_control(void)
 537{
 538	u32 control = 0;
 539
 540	if (IS_ENABLED(CONFIG_MEMORY_FAILURE))
 541		control |= OSC_CXL_ERROR_REPORTING_CONTROL;
 542
 543	return control;
 544}
 545
 546static bool os_control_query_checks(struct acpi_pci_root *root, u32 support)
 547{
 548	struct acpi_device *device = root->device;
 549
 550	if (pcie_ports_disabled) {
 551		dev_info(&device->dev, "PCIe port services disabled; not requesting _OSC control\n");
 552		return false;
 553	}
 554
 555	if ((support & ACPI_PCIE_REQ_SUPPORT) != ACPI_PCIE_REQ_SUPPORT) {
 556		decode_osc_support(root, "not requesting OS control; OS requires",
 557				   ACPI_PCIE_REQ_SUPPORT);
 558		return false;
 559	}
 560
 561	return true;
 562}
 
 563
 564static void negotiate_os_control(struct acpi_pci_root *root, int *no_aspm)
 565{
 566	u32 support, control = 0, requested = 0;
 567	u32 cxl_support = 0, cxl_control = 0, cxl_requested = 0;
 568	acpi_status status;
 569	struct acpi_device *device = root->device;
 570	acpi_handle handle = device->handle;
 571
 572	/*
 573	 * Apple always return failure on _OSC calls when _OSI("Darwin") has
 574	 * been called successfully. We know the feature set supported by the
 575	 * platform, so avoid calling _OSC at all
 576	 */
 577	if (x86_apple_machine) {
 578		root->osc_control_set = ~OSC_PCI_EXPRESS_PME_CONTROL;
 579		decode_osc_control(root, "OS assumes control of",
 580				   root->osc_control_set);
 581		return;
 582	}
 583
 584	support = calculate_support();
 585
 586	decode_osc_support(root, "OS supports", support);
 587
 588	if (os_control_query_checks(root, support))
 589		requested = control = calculate_control();
 590
 591	if (is_cxl(root)) {
 592		cxl_support = calculate_cxl_support();
 593		decode_cxl_osc_support(root, "OS supports", cxl_support);
 594		cxl_requested = cxl_control = calculate_cxl_control();
 595	}
 596
 597	status = acpi_pci_osc_control_set(handle, &control, support,
 598					  &cxl_control, cxl_support);
 599	if (ACPI_SUCCESS(status)) {
 600		if (control)
 601			decode_osc_control(root, "OS now controls", control);
 602		if (cxl_control)
 603			decode_cxl_osc_control(root, "OS now controls",
 604					   cxl_control);
 605
 606		if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_ASPM) {
 607			/*
 608			 * We have ASPM control, but the FADT indicates that
 609			 * it's unsupported. Leave existing configuration
 610			 * intact and prevent the OS from touching it.
 611			 */
 612			dev_info(&device->dev, "FADT indicates ASPM is unsupported, using BIOS configuration\n");
 613			*no_aspm = 1;
 614		}
 615	} else {
 616		/*
 617		 * We want to disable ASPM here, but aspm_disabled
 618		 * needs to remain in its state from boot so that we
 619		 * properly handle PCIe 1.1 devices.  So we set this
 620		 * flag here, to defer the action until after the ACPI
 621		 * root scan.
 622		 */
 623		*no_aspm = 1;
 624
 625		/* _OSC is optional for PCI host bridges */
 626		if (status == AE_NOT_FOUND && !is_pcie(root))
 627			return;
 628
 629		if (control) {
 630			decode_osc_control(root, "OS requested", requested);
 631			decode_osc_control(root, "platform willing to grant", control);
 632		}
 633		if (cxl_control) {
 634			decode_cxl_osc_control(root, "OS requested", cxl_requested);
 635			decode_cxl_osc_control(root, "platform willing to grant",
 636					   cxl_control);
 637		}
 638
 639		dev_info(&device->dev, "_OSC: platform retains control of PCIe features (%s)\n",
 640			 acpi_format_exception(status));
 641	}
 642}
 643
 644static int acpi_pci_root_add(struct acpi_device *device,
 645			     const struct acpi_device_id *not_used)
 646{
 647	unsigned long long segment, bus;
 648	acpi_status status;
 649	int result;
 650	struct acpi_pci_root *root;
 651	acpi_handle handle = device->handle;
 652	int no_aspm = 0;
 653	bool hotadd = system_state == SYSTEM_RUNNING;
 654	const char *acpi_hid;
 655
 656	root = kzalloc(sizeof(struct acpi_pci_root), GFP_KERNEL);
 657	if (!root)
 658		return -ENOMEM;
 659
 660	segment = 0;
 661	status = acpi_evaluate_integer(handle, METHOD_NAME__SEG, NULL,
 662				       &segment);
 663	if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
 664		dev_err(&device->dev,  "can't evaluate _SEG\n");
 665		result = -ENODEV;
 666		goto end;
 667	}
 668
 669	/* Check _CRS first, then _BBN.  If no _BBN, default to zero. */
 670	root->secondary.flags = IORESOURCE_BUS;
 671	status = try_get_root_bridge_busnr(handle, &root->secondary);
 672	if (ACPI_FAILURE(status)) {
 673		/*
 674		 * We need both the start and end of the downstream bus range
 675		 * to interpret _CBA (MMCONFIG base address), so it really is
 676		 * supposed to be in _CRS.  If we don't find it there, all we
 677		 * can do is assume [_BBN-0xFF] or [0-0xFF].
 678		 */
 679		root->secondary.end = 0xFF;
 680		dev_warn(&device->dev,
 681			 FW_BUG "no secondary bus range in _CRS\n");
 682		status = acpi_evaluate_integer(handle, METHOD_NAME__BBN,
 683					       NULL, &bus);
 684		if (ACPI_SUCCESS(status))
 685			root->secondary.start = bus;
 686		else if (status == AE_NOT_FOUND)
 687			root->secondary.start = 0;
 688		else {
 689			dev_err(&device->dev, "can't evaluate _BBN\n");
 690			result = -ENODEV;
 691			goto end;
 692		}
 693	}
 694
 
 695	root->device = device;
 696	root->segment = segment & 0xFFFF;
 697	strcpy(acpi_device_name(device), ACPI_PCI_ROOT_DEVICE_NAME);
 698	strcpy(acpi_device_class(device), ACPI_PCI_ROOT_CLASS);
 699	device->driver_data = root;
 700
 701	if (hotadd && dmar_device_add(handle)) {
 702		result = -ENXIO;
 703		goto end;
 704	}
 705
 706	pr_info("%s [%s] (domain %04x %pR)\n",
 707	       acpi_device_name(device), acpi_device_bid(device),
 708	       root->segment, &root->secondary);
 709
 710	root->mcfg_addr = acpi_pci_root_get_mcfg_addr(handle);
 711
 712	acpi_hid = acpi_device_hid(root->device);
 713	if (strcmp(acpi_hid, "PNP0A08") == 0)
 714		root->bridge_type = ACPI_BRIDGE_TYPE_PCIE;
 715	else if (strcmp(acpi_hid, "ACPI0016") == 0)
 716		root->bridge_type = ACPI_BRIDGE_TYPE_CXL;
 717	else
 718		dev_dbg(&device->dev, "Assuming non-PCIe host bridge\n");
 719
 720	negotiate_os_control(root, &no_aspm);
 721
 722	/*
 723	 * TBD: Need PCI interface for enumeration/configuration of roots.
 724	 */
 725
 
 
 
 
 
 
 
 726	/*
 727	 * Scan the Root Bridge
 728	 * --------------------
 729	 * Must do this prior to any attempt to bind the root device, as the
 730	 * PCI namespace does not get created until this call is made (and
 731	 * thus the root bridge's pci_dev does not exist).
 732	 */
 733	root->bus = pci_acpi_scan_root(root);
 734	if (!root->bus) {
 735		dev_err(&device->dev,
 736			"Bus %04x:%02x not present in PCI namespace\n",
 737			root->segment, (unsigned int)root->secondary.start);
 738		device->driver_data = NULL;
 739		result = -ENODEV;
 740		goto remove_dmar;
 741	}
 742
 743	if (no_aspm)
 744		pcie_no_aspm();
 
 
 
 
 
 
 745
 746	pci_acpi_add_bus_pm_notifier(device);
 747	device_set_wakeup_capable(root->bus->bridge, device->wakeup.flags.valid);
 
 
 
 
 
 
 748
 749	if (hotadd) {
 750		pcibios_resource_survey_bus(root->bus);
 751		pci_assign_unassigned_root_bus_resources(root->bus);
 752		/*
 753		 * This is only called for the hotadd case. For the boot-time
 754		 * case, we need to wait until after PCI initialization in
 755		 * order to deal with IOAPICs mapped in on a PCI BAR.
 756		 *
 757		 * This is currently x86-specific, because acpi_ioapic_add()
 758		 * is an empty function without CONFIG_ACPI_HOTPLUG_IOAPIC.
 759		 * And CONFIG_ACPI_HOTPLUG_IOAPIC depends on CONFIG_X86_IO_APIC
 760		 * (see drivers/acpi/Kconfig).
 761		 */
 762		acpi_ioapic_add(root->device->handle);
 763	}
 764
 765	pci_lock_rescan_remove();
 766	pci_bus_add_devices(root->bus);
 767	pci_unlock_rescan_remove();
 768	return 1;
 769
 770remove_dmar:
 771	if (hotadd)
 772		dmar_device_remove(handle);
 773end:
 774	kfree(root);
 775	return result;
 776}
 777
 778static void acpi_pci_root_remove(struct acpi_device *device)
 779{
 780	struct acpi_pci_root *root = acpi_driver_data(device);
 781
 782	pci_lock_rescan_remove();
 783
 784	pci_stop_root_bus(root->bus);
 785
 786	pci_ioapic_remove(root);
 787	device_set_wakeup_capable(root->bus->bridge, false);
 788	pci_acpi_remove_bus_pm_notifier(device);
 789
 790	pci_remove_root_bus(root->bus);
 791	WARN_ON(acpi_ioapic_remove(root));
 792
 793	dmar_device_remove(device->handle);
 
 794
 795	pci_unlock_rescan_remove();
 796
 797	kfree(root);
 798}
 799
 800/*
 801 * Following code to support acpi_pci_root_create() is copied from
 802 * arch/x86/pci/acpi.c and modified so it could be reused by x86, IA64
 803 * and ARM64.
 804 */
 805static void acpi_pci_root_validate_resources(struct device *dev,
 806					     struct list_head *resources,
 807					     unsigned long type)
 808{
 809	LIST_HEAD(list);
 810	struct resource *res1, *res2, *root = NULL;
 811	struct resource_entry *tmp, *entry, *entry2;
 812
 813	BUG_ON((type & (IORESOURCE_MEM | IORESOURCE_IO)) == 0);
 814	root = (type & IORESOURCE_MEM) ? &iomem_resource : &ioport_resource;
 815
 816	list_splice_init(resources, &list);
 817	resource_list_for_each_entry_safe(entry, tmp, &list) {
 818		bool free = false;
 819		resource_size_t end;
 820
 821		res1 = entry->res;
 822		if (!(res1->flags & type))
 823			goto next;
 824
 825		/* Exclude non-addressable range or non-addressable portion */
 826		end = min(res1->end, root->end);
 827		if (end <= res1->start) {
 828			dev_info(dev, "host bridge window %pR (ignored, not CPU addressable)\n",
 829				 res1);
 830			free = true;
 831			goto next;
 832		} else if (res1->end != end) {
 833			dev_info(dev, "host bridge window %pR ([%#llx-%#llx] ignored, not CPU addressable)\n",
 834				 res1, (unsigned long long)end + 1,
 835				 (unsigned long long)res1->end);
 836			res1->end = end;
 837		}
 838
 839		resource_list_for_each_entry(entry2, resources) {
 840			res2 = entry2->res;
 841			if (!(res2->flags & type))
 842				continue;
 843
 844			/*
 845			 * I don't like throwing away windows because then
 846			 * our resources no longer match the ACPI _CRS, but
 847			 * the kernel resource tree doesn't allow overlaps.
 848			 */
 849			if (resource_union(res1, res2, res2)) {
 850				dev_info(dev, "host bridge window expanded to %pR; %pR ignored\n",
 851					 res2, res1);
 852				free = true;
 853				goto next;
 854			}
 
 
 
 
 
 
 
 
 855		}
 856
 857next:
 858		resource_list_del(entry);
 859		if (free)
 860			resource_list_free_entry(entry);
 861		else
 862			resource_list_add_tail(entry, resources);
 863	}
 864}
 865
 866static void acpi_pci_root_remap_iospace(struct fwnode_handle *fwnode,
 867			struct resource_entry *entry)
 868{
 869#ifdef PCI_IOBASE
 870	struct resource *res = entry->res;
 871	resource_size_t cpu_addr = res->start;
 872	resource_size_t pci_addr = cpu_addr - entry->offset;
 873	resource_size_t length = resource_size(res);
 874	unsigned long port;
 875
 876	if (pci_register_io_range(fwnode, cpu_addr, length))
 877		goto err;
 878
 879	port = pci_address_to_pio(cpu_addr);
 880	if (port == (unsigned long)-1)
 881		goto err;
 882
 883	res->start = port;
 884	res->end = port + length - 1;
 885	entry->offset = port - pci_addr;
 886
 887	if (pci_remap_iospace(res, cpu_addr) < 0)
 888		goto err;
 889
 890	pr_info("Remapped I/O %pa to %pR\n", &cpu_addr, res);
 891	return;
 892err:
 893	res->flags |= IORESOURCE_DISABLED;
 894#endif
 895}
 896
 897int acpi_pci_probe_root_resources(struct acpi_pci_root_info *info)
 898{
 899	int ret;
 900	struct list_head *list = &info->resources;
 901	struct acpi_device *device = info->bridge;
 902	struct resource_entry *entry, *tmp;
 903	unsigned long flags;
 904
 905	flags = IORESOURCE_IO | IORESOURCE_MEM | IORESOURCE_MEM_8AND16BIT;
 906	ret = acpi_dev_get_resources(device, list,
 907				     acpi_dev_filter_resource_type_cb,
 908				     (void *)flags);
 909	if (ret < 0)
 910		dev_warn(&device->dev,
 911			 "failed to parse _CRS method, error code %d\n", ret);
 912	else if (ret == 0)
 913		dev_dbg(&device->dev,
 914			"no IO and memory resources present in _CRS\n");
 915	else {
 916		resource_list_for_each_entry_safe(entry, tmp, list) {
 917			if (entry->res->flags & IORESOURCE_IO)
 918				acpi_pci_root_remap_iospace(&device->fwnode,
 919						entry);
 920
 921			if (entry->res->flags & IORESOURCE_DISABLED)
 922				resource_list_destroy_entry(entry);
 923			else
 924				entry->res->name = info->name;
 925		}
 926		acpi_pci_root_validate_resources(&device->dev, list,
 927						 IORESOURCE_MEM);
 928		acpi_pci_root_validate_resources(&device->dev, list,
 929						 IORESOURCE_IO);
 930	}
 931
 932	return ret;
 933}
 934
 935static void pci_acpi_root_add_resources(struct acpi_pci_root_info *info)
 936{
 937	struct resource_entry *entry, *tmp;
 938	struct resource *res, *conflict, *root = NULL;
 939
 940	resource_list_for_each_entry_safe(entry, tmp, &info->resources) {
 941		res = entry->res;
 942		if (res->flags & IORESOURCE_MEM)
 943			root = &iomem_resource;
 944		else if (res->flags & IORESOURCE_IO)
 945			root = &ioport_resource;
 946		else
 947			continue;
 948
 949		/*
 950		 * Some legacy x86 host bridge drivers use iomem_resource and
 951		 * ioport_resource as default resource pool, skip it.
 952		 */
 953		if (res == root)
 954			continue;
 955
 956		conflict = insert_resource_conflict(root, res);
 957		if (conflict) {
 958			dev_info(&info->bridge->dev,
 959				 "ignoring host bridge window %pR (conflicts with %s %pR)\n",
 960				 res, conflict->name, conflict);
 961			resource_list_destroy_entry(entry);
 962		}
 963	}
 964}
 965
 966static void __acpi_pci_root_release_info(struct acpi_pci_root_info *info)
 967{
 968	struct resource *res;
 969	struct resource_entry *entry, *tmp;
 970
 971	if (!info)
 972		return;
 973
 974	resource_list_for_each_entry_safe(entry, tmp, &info->resources) {
 975		res = entry->res;
 976		if (res->parent &&
 977		    (res->flags & (IORESOURCE_MEM | IORESOURCE_IO)))
 978			release_resource(res);
 979		resource_list_destroy_entry(entry);
 980	}
 981
 982	info->ops->release_info(info);
 983}
 984
 985static void acpi_pci_root_release_info(struct pci_host_bridge *bridge)
 986{
 987	struct resource *res;
 988	struct resource_entry *entry;
 989
 990	resource_list_for_each_entry(entry, &bridge->windows) {
 991		res = entry->res;
 992		if (res->flags & IORESOURCE_IO)
 993			pci_unmap_iospace(res);
 994		if (res->parent &&
 995		    (res->flags & (IORESOURCE_MEM | IORESOURCE_IO)))
 996			release_resource(res);
 997	}
 998	__acpi_pci_root_release_info(bridge->release_data);
 999}
1000
1001struct pci_bus *acpi_pci_root_create(struct acpi_pci_root *root,
1002				     struct acpi_pci_root_ops *ops,
1003				     struct acpi_pci_root_info *info,
1004				     void *sysdata)
1005{
1006	int ret, busnum = root->secondary.start;
1007	struct acpi_device *device = root->device;
1008	int node = acpi_get_node(device->handle);
1009	struct pci_bus *bus;
1010	struct pci_host_bridge *host_bridge;
1011	union acpi_object *obj;
1012
1013	info->root = root;
1014	info->bridge = device;
1015	info->ops = ops;
1016	INIT_LIST_HEAD(&info->resources);
1017	snprintf(info->name, sizeof(info->name), "PCI Bus %04x:%02x",
1018		 root->segment, busnum);
1019
1020	if (ops->init_info && ops->init_info(info))
1021		goto out_release_info;
1022	if (ops->prepare_resources)
1023		ret = ops->prepare_resources(info);
1024	else
1025		ret = acpi_pci_probe_root_resources(info);
1026	if (ret < 0)
1027		goto out_release_info;
1028
1029	pci_acpi_root_add_resources(info);
1030	pci_add_resource(&info->resources, &root->secondary);
1031	bus = pci_create_root_bus(NULL, busnum, ops->pci_ops,
1032				  sysdata, &info->resources);
1033	if (!bus)
1034		goto out_release_info;
1035
1036	host_bridge = to_pci_host_bridge(bus->bridge);
1037	if (!(root->osc_control_set & OSC_PCI_EXPRESS_NATIVE_HP_CONTROL))
1038		host_bridge->native_pcie_hotplug = 0;
1039	if (!(root->osc_control_set & OSC_PCI_SHPC_NATIVE_HP_CONTROL))
1040		host_bridge->native_shpc_hotplug = 0;
1041	if (!(root->osc_control_set & OSC_PCI_EXPRESS_AER_CONTROL))
1042		host_bridge->native_aer = 0;
1043	if (!(root->osc_control_set & OSC_PCI_EXPRESS_PME_CONTROL))
1044		host_bridge->native_pme = 0;
1045	if (!(root->osc_control_set & OSC_PCI_EXPRESS_LTR_CONTROL))
1046		host_bridge->native_ltr = 0;
1047	if (!(root->osc_control_set & OSC_PCI_EXPRESS_DPC_CONTROL))
1048		host_bridge->native_dpc = 0;
1049
1050	/*
1051	 * Evaluate the "PCI Boot Configuration" _DSM Function.  If it
1052	 * exists and returns 0, we must preserve any PCI resource
1053	 * assignments made by firmware for this host bridge.
1054	 */
1055	obj = acpi_evaluate_dsm(ACPI_HANDLE(bus->bridge), &pci_acpi_dsm_guid, 1,
1056				DSM_PCI_PRESERVE_BOOT_CONFIG, NULL);
1057	if (obj && obj->type == ACPI_TYPE_INTEGER && obj->integer.value == 0)
1058		host_bridge->preserve_config = 1;
1059	ACPI_FREE(obj);
1060
1061	acpi_dev_power_up_children_with_adr(device);
1062
1063	pci_scan_child_bus(bus);
1064	pci_set_host_bridge_release(host_bridge, acpi_pci_root_release_info,
1065				    info);
1066	if (node != NUMA_NO_NODE)
1067		dev_printk(KERN_DEBUG, &bus->dev, "on NUMA node %d\n", node);
1068	return bus;
1069
1070out_release_info:
1071	__acpi_pci_root_release_info(info);
1072	return NULL;
1073}
1074
1075void __init acpi_pci_root_init(void)
1076{
1077	if (acpi_pci_disabled)
1078		return;
1079
1080	pci_acpi_crs_quirks();
1081	acpi_scan_add_handler_with_hotplug(&pci_root_handler, "pci_root");
1082}