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  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Purpose:	PCI Express Port Bus Driver
  4 *
  5 * Copyright (C) 2004 Intel
  6 * Copyright (C) Tom Long Nguyen (tom.l.nguyen@intel.com)
  7 */
  8
  9#include <linux/bitfield.h>
 10#include <linux/dmi.h>
 11#include <linux/init.h>
 12#include <linux/module.h>
 13#include <linux/pci.h>
 14#include <linux/kernel.h>
 15#include <linux/errno.h>
 16#include <linux/pm.h>
 17#include <linux/pm_runtime.h>
 18#include <linux/string.h>
 19#include <linux/slab.h>
 20#include <linux/aer.h>
 21
 22#include "../pci.h"
 23#include "portdrv.h"
 24
 25/*
 26 * The PCIe Capability Interrupt Message Number (PCIe r3.1, sec 7.8.2) must
 27 * be one of the first 32 MSI-X entries.  Per PCI r3.0, sec 6.8.3.1, MSI
 28 * supports a maximum of 32 vectors per function.
 29 */
 30#define PCIE_PORT_MAX_MSI_ENTRIES	32
 31
 32#define get_descriptor_id(type, service) (((type - 4) << 8) | service)
 33
 34struct portdrv_service_data {
 35	struct pcie_port_service_driver *drv;
 36	struct device *dev;
 37	u32 service;
 38};
 39
 40/**
 41 * release_pcie_device - free PCI Express port service device structure
 42 * @dev: Port service device to release
 43 *
 44 * Invoked automatically when device is being removed in response to
 45 * device_unregister(dev).  Release all resources being claimed.
 46 */
 47static void release_pcie_device(struct device *dev)
 48{
 49	kfree(to_pcie_device(dev));
 50}
 51
 52/*
 53 * Fill in *pme, *aer, *dpc with the relevant Interrupt Message Numbers if
 54 * services are enabled in "mask".  Return the number of MSI/MSI-X vectors
 55 * required to accommodate the largest Message Number.
 56 */
 57static int pcie_message_numbers(struct pci_dev *dev, int mask,
 58				u32 *pme, u32 *aer, u32 *dpc)
 59{
 60	u32 nvec = 0, pos;
 61	u16 reg16;
 62
 63	/*
 64	 * The Interrupt Message Number indicates which vector is used, i.e.,
 65	 * the MSI-X table entry or the MSI offset between the base Message
 66	 * Data and the generated interrupt message.  See PCIe r3.1, sec
 67	 * 7.8.2, 7.10.10, 7.31.2.
 68	 */
 69
 70	if (mask & (PCIE_PORT_SERVICE_PME | PCIE_PORT_SERVICE_HP |
 71		    PCIE_PORT_SERVICE_BWCTRL)) {
 72		pcie_capability_read_word(dev, PCI_EXP_FLAGS, &reg16);
 73		*pme = FIELD_GET(PCI_EXP_FLAGS_IRQ, reg16);
 74		nvec = *pme + 1;
 75	}
 76
 77#ifdef CONFIG_PCIEAER
 78	if (mask & PCIE_PORT_SERVICE_AER) {
 79		u32 reg32;
 80
 81		pos = dev->aer_cap;
 82		if (pos) {
 83			pci_read_config_dword(dev, pos + PCI_ERR_ROOT_STATUS,
 84					      &reg32);
 85			*aer = FIELD_GET(PCI_ERR_ROOT_AER_IRQ, reg32);
 86			nvec = max(nvec, *aer + 1);
 87		}
 88	}
 89#endif
 90
 91	if (mask & PCIE_PORT_SERVICE_DPC) {
 92		pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_DPC);
 93		if (pos) {
 94			pci_read_config_word(dev, pos + PCI_EXP_DPC_CAP,
 95					     &reg16);
 96			*dpc = FIELD_GET(PCI_EXP_DPC_IRQ, reg16);
 97			nvec = max(nvec, *dpc + 1);
 98		}
 99	}
100
101	return nvec;
102}
103
104/**
105 * pcie_port_enable_irq_vec - try to set up MSI-X or MSI as interrupt mode
106 * for given port
107 * @dev: PCI Express port to handle
108 * @irqs: Array of interrupt vectors to populate
109 * @mask: Bitmask of port capabilities returned by get_port_device_capability()
110 *
111 * Return value: 0 on success, error code on failure
112 */
113static int pcie_port_enable_irq_vec(struct pci_dev *dev, int *irqs, int mask)
114{
115	int nr_entries, nvec, pcie_irq;
116	u32 pme = 0, aer = 0, dpc = 0;
117
118	/* Allocate the maximum possible number of MSI/MSI-X vectors */
119	nr_entries = pci_alloc_irq_vectors(dev, 1, PCIE_PORT_MAX_MSI_ENTRIES,
120			PCI_IRQ_MSIX | PCI_IRQ_MSI);
121	if (nr_entries < 0)
122		return nr_entries;
123
124	/* See how many and which Interrupt Message Numbers we actually use */
125	nvec = pcie_message_numbers(dev, mask, &pme, &aer, &dpc);
126	if (nvec > nr_entries) {
127		pci_free_irq_vectors(dev);
128		return -EIO;
129	}
130
131	/*
132	 * If we allocated more than we need, free them and reallocate fewer.
133	 *
134	 * Reallocating may change the specific vectors we get, so
135	 * pci_irq_vector() must be done *after* the reallocation.
136	 *
137	 * If we're using MSI, hardware is *allowed* to change the Interrupt
138	 * Message Numbers when we free and reallocate the vectors, but we
139	 * assume it won't because we allocate enough vectors for the
140	 * biggest Message Number we found.
141	 */
142	if (nvec != nr_entries) {
143		pci_free_irq_vectors(dev);
144
145		nr_entries = pci_alloc_irq_vectors(dev, nvec, nvec,
146				PCI_IRQ_MSIX | PCI_IRQ_MSI);
147		if (nr_entries < 0)
148			return nr_entries;
149	}
150
151	/* PME, hotplug and bandwidth notification share an MSI/MSI-X vector */
152	if (mask & (PCIE_PORT_SERVICE_PME | PCIE_PORT_SERVICE_HP |
153		    PCIE_PORT_SERVICE_BWCTRL)) {
154		pcie_irq = pci_irq_vector(dev, pme);
155		irqs[PCIE_PORT_SERVICE_PME_SHIFT] = pcie_irq;
156		irqs[PCIE_PORT_SERVICE_HP_SHIFT] = pcie_irq;
157		irqs[PCIE_PORT_SERVICE_BWCTRL_SHIFT] = pcie_irq;
158	}
159
160	if (mask & PCIE_PORT_SERVICE_AER)
161		irqs[PCIE_PORT_SERVICE_AER_SHIFT] = pci_irq_vector(dev, aer);
162
163	if (mask & PCIE_PORT_SERVICE_DPC)
164		irqs[PCIE_PORT_SERVICE_DPC_SHIFT] = pci_irq_vector(dev, dpc);
165
166	return 0;
167}
168
169/**
170 * pcie_init_service_irqs - initialize irqs for PCI Express port services
171 * @dev: PCI Express port to handle
172 * @irqs: Array of irqs to populate
173 * @mask: Bitmask of port capabilities returned by get_port_device_capability()
174 *
175 * Return value: Interrupt mode associated with the port
176 */
177static int pcie_init_service_irqs(struct pci_dev *dev, int *irqs, int mask)
178{
179	int ret, i;
180
181	for (i = 0; i < PCIE_PORT_DEVICE_MAXSERVICES; i++)
182		irqs[i] = -1;
183
184	/*
185	 * If we support PME but can't use MSI/MSI-X for it, we have to
186	 * fall back to INTx or other interrupts, e.g., a system shared
187	 * interrupt.
188	 */
189	if ((mask & PCIE_PORT_SERVICE_PME) && pcie_pme_no_msi())
190		goto intx_irq;
191
192	/* Try to use MSI-X or MSI if supported */
193	if (pcie_port_enable_irq_vec(dev, irqs, mask) == 0)
194		return 0;
195
196intx_irq:
197	/* fall back to INTX IRQ */
198	ret = pci_alloc_irq_vectors(dev, 1, 1, PCI_IRQ_INTX);
199	if (ret < 0)
200		return -ENODEV;
201
202	for (i = 0; i < PCIE_PORT_DEVICE_MAXSERVICES; i++)
203		irqs[i] = pci_irq_vector(dev, 0);
204
205	return 0;
206}
207
208/**
209 * get_port_device_capability - discover capabilities of a PCI Express port
210 * @dev: PCI Express port to examine
211 *
212 * The capabilities are read from the port's PCI Express configuration registers
213 * as described in PCI Express Base Specification 1.0a sections 7.8.2, 7.8.9 and
214 * 7.9 - 7.11.
215 *
216 * Return value: Bitmask of discovered port capabilities
217 */
218static int get_port_device_capability(struct pci_dev *dev)
219{
220	struct pci_host_bridge *host = pci_find_host_bridge(dev->bus);
221	int services = 0;
222
223	if (dev->is_hotplug_bridge &&
224	    (pci_pcie_type(dev) == PCI_EXP_TYPE_ROOT_PORT ||
225	     pci_pcie_type(dev) == PCI_EXP_TYPE_DOWNSTREAM) &&
226	    (pcie_ports_native || host->native_pcie_hotplug)) {
227		services |= PCIE_PORT_SERVICE_HP;
228
229		/*
230		 * Disable hot-plug interrupts in case they have been enabled
231		 * by the BIOS and the hot-plug service driver is not loaded.
232		 */
233		pcie_capability_clear_word(dev, PCI_EXP_SLTCTL,
234			  PCI_EXP_SLTCTL_CCIE | PCI_EXP_SLTCTL_HPIE);
235	}
236
237#ifdef CONFIG_PCIEAER
238	if ((pci_pcie_type(dev) == PCI_EXP_TYPE_ROOT_PORT ||
239             pci_pcie_type(dev) == PCI_EXP_TYPE_RC_EC) &&
240	    dev->aer_cap && pci_aer_available() &&
241	    (pcie_ports_native || host->native_aer))
242		services |= PCIE_PORT_SERVICE_AER;
243#endif
244
245	/* Root Ports and Root Complex Event Collectors may generate PMEs */
246	if ((pci_pcie_type(dev) == PCI_EXP_TYPE_ROOT_PORT ||
247	     pci_pcie_type(dev) == PCI_EXP_TYPE_RC_EC) &&
248	    (pcie_ports_native || host->native_pme)) {
249		services |= PCIE_PORT_SERVICE_PME;
250
251		/*
252		 * Disable PME interrupt on this port in case it's been enabled
253		 * by the BIOS (the PME service driver will enable it when
254		 * necessary).
255		 */
256		pcie_pme_interrupt_enable(dev, false);
257	}
258
259	/*
260	 * With dpc-native, allow Linux to use DPC even if it doesn't have
261	 * permission to use AER.
262	 */
263	if (pci_find_ext_capability(dev, PCI_EXT_CAP_ID_DPC) &&
264	    pci_aer_available() &&
265	    (pcie_ports_dpc_native || (services & PCIE_PORT_SERVICE_AER)))
266		services |= PCIE_PORT_SERVICE_DPC;
267
268	/* Enable bandwidth control if more than one speed is supported. */
269	if (pci_pcie_type(dev) == PCI_EXP_TYPE_DOWNSTREAM ||
270	    pci_pcie_type(dev) == PCI_EXP_TYPE_ROOT_PORT) {
271		u32 linkcap;
272
273		pcie_capability_read_dword(dev, PCI_EXP_LNKCAP, &linkcap);
274		if (linkcap & PCI_EXP_LNKCAP_LBNC &&
275		    hweight8(dev->supported_speeds) > 1)
276			services |= PCIE_PORT_SERVICE_BWCTRL;
277	}
278
279	return services;
280}
281
282/**
283 * pcie_device_init - allocate and initialize PCI Express port service device
284 * @pdev: PCI Express port to associate the service device with
285 * @service: Type of service to associate with the service device
286 * @irq: Interrupt vector to associate with the service device
287 */
288static int pcie_device_init(struct pci_dev *pdev, int service, int irq)
289{
290	int retval;
291	struct pcie_device *pcie;
292	struct device *device;
293
294	pcie = kzalloc(sizeof(*pcie), GFP_KERNEL);
295	if (!pcie)
296		return -ENOMEM;
297	pcie->port = pdev;
298	pcie->irq = irq;
299	pcie->service = service;
300
301	/* Initialize generic device interface */
302	device = &pcie->device;
303	device->bus = &pcie_port_bus_type;
304	device->release = release_pcie_device;	/* callback to free pcie dev */
305	dev_set_name(device, "%s:pcie%03x",
306		     pci_name(pdev),
307		     get_descriptor_id(pci_pcie_type(pdev), service));
308	device->parent = &pdev->dev;
309	device_enable_async_suspend(device);
310
311	retval = device_register(device);
312	if (retval) {
313		put_device(device);
314		return retval;
315	}
316
317	pm_runtime_no_callbacks(device);
318
319	return 0;
320}
321
322/**
323 * pcie_port_device_register - register PCI Express port
324 * @dev: PCI Express port to register
325 *
326 * Allocate the port extension structure and register services associated with
327 * the port.
328 */
329static int pcie_port_device_register(struct pci_dev *dev)
330{
331	int status, capabilities, i, nr_service;
332	int irqs[PCIE_PORT_DEVICE_MAXSERVICES];
333
334	/* Enable PCI Express port device */
335	status = pci_enable_device(dev);
336	if (status)
337		return status;
338
339	/* Get and check PCI Express port services */
340	capabilities = get_port_device_capability(dev);
341	if (!capabilities)
342		return 0;
343
344	pci_set_master(dev);
345	/*
346	 * Initialize service irqs. Don't use service devices that
347	 * require interrupts if there is no way to generate them.
348	 * However, some drivers may have a polling mode (e.g. pciehp_poll_mode)
349	 * that can be used in the absence of irqs.  Allow them to determine
350	 * if that is to be used.
351	 */
352	status = pcie_init_service_irqs(dev, irqs, capabilities);
353	if (status) {
354		capabilities &= PCIE_PORT_SERVICE_HP;
355		if (!capabilities)
356			goto error_disable;
357	}
358
359	/* Allocate child services if any */
360	status = -ENODEV;
361	nr_service = 0;
362	for (i = 0; i < PCIE_PORT_DEVICE_MAXSERVICES; i++) {
363		int service = 1 << i;
364		if (!(capabilities & service))
365			continue;
366		if (!pcie_device_init(dev, service, irqs[i]))
367			nr_service++;
368	}
369	if (!nr_service)
370		goto error_cleanup_irqs;
371
372	return 0;
373
374error_cleanup_irqs:
375	pci_free_irq_vectors(dev);
376error_disable:
377	pci_disable_device(dev);
378	return status;
379}
380
381typedef int (*pcie_callback_t)(struct pcie_device *);
382
383static int pcie_port_device_iter(struct device *dev, void *data)
384{
385	struct pcie_port_service_driver *service_driver;
386	size_t offset = *(size_t *)data;
387	pcie_callback_t cb;
388
389	if ((dev->bus == &pcie_port_bus_type) && dev->driver) {
390		service_driver = to_service_driver(dev->driver);
391		cb = *(pcie_callback_t *)((void *)service_driver + offset);
392		if (cb)
393			return cb(to_pcie_device(dev));
394	}
395	return 0;
396}
397
398#ifdef CONFIG_PM
399/**
400 * pcie_port_device_suspend - suspend port services associated with a PCIe port
401 * @dev: PCI Express port to handle
402 */
403static int pcie_port_device_suspend(struct device *dev)
404{
405	size_t off = offsetof(struct pcie_port_service_driver, suspend);
406	return device_for_each_child(dev, &off, pcie_port_device_iter);
407}
408
409static int pcie_port_device_resume_noirq(struct device *dev)
410{
411	size_t off = offsetof(struct pcie_port_service_driver, resume_noirq);
412	return device_for_each_child(dev, &off, pcie_port_device_iter);
413}
414
415/**
416 * pcie_port_device_resume - resume port services associated with a PCIe port
417 * @dev: PCI Express port to handle
418 */
419static int pcie_port_device_resume(struct device *dev)
420{
421	size_t off = offsetof(struct pcie_port_service_driver, resume);
422	return device_for_each_child(dev, &off, pcie_port_device_iter);
423}
424
425/**
426 * pcie_port_device_runtime_suspend - runtime suspend port services
427 * @dev: PCI Express port to handle
428 */
429static int pcie_port_device_runtime_suspend(struct device *dev)
430{
431	size_t off = offsetof(struct pcie_port_service_driver, runtime_suspend);
432	return device_for_each_child(dev, &off, pcie_port_device_iter);
433}
434
435/**
436 * pcie_port_device_runtime_resume - runtime resume port services
437 * @dev: PCI Express port to handle
438 */
439static int pcie_port_device_runtime_resume(struct device *dev)
440{
441	size_t off = offsetof(struct pcie_port_service_driver, runtime_resume);
442	return device_for_each_child(dev, &off, pcie_port_device_iter);
443}
444#endif /* PM */
445
446static int remove_iter(struct device *dev, void *data)
447{
448	if (dev->bus == &pcie_port_bus_type)
449		device_unregister(dev);
450	return 0;
451}
452
453static int find_service_iter(struct device *device, void *data)
454{
455	struct pcie_port_service_driver *service_driver;
456	struct portdrv_service_data *pdrvs;
457	u32 service;
458
459	pdrvs = (struct portdrv_service_data *) data;
460	service = pdrvs->service;
461
462	if (device->bus == &pcie_port_bus_type && device->driver) {
463		service_driver = to_service_driver(device->driver);
464		if (service_driver->service == service) {
465			pdrvs->drv = service_driver;
466			pdrvs->dev = device;
467			return 1;
468		}
469	}
470
471	return 0;
472}
473
474/**
475 * pcie_port_find_device - find the struct device
476 * @dev: PCI Express port the service is associated with
477 * @service: For the service to find
478 *
479 * Find the struct device associated with given service on a pci_dev
480 */
481struct device *pcie_port_find_device(struct pci_dev *dev,
482				      u32 service)
483{
484	struct device *device;
485	struct portdrv_service_data pdrvs;
486
487	pdrvs.dev = NULL;
488	pdrvs.service = service;
489	device_for_each_child(&dev->dev, &pdrvs, find_service_iter);
490
491	device = pdrvs.dev;
492	return device;
493}
494EXPORT_SYMBOL_GPL(pcie_port_find_device);
495
496/**
497 * pcie_port_device_remove - unregister PCI Express port service devices
498 * @dev: PCI Express port the service devices to unregister are associated with
499 *
500 * Remove PCI Express port service devices associated with given port and
501 * disable MSI-X or MSI for the port.
502 */
503static void pcie_port_device_remove(struct pci_dev *dev)
504{
505	device_for_each_child(&dev->dev, NULL, remove_iter);
506	pci_free_irq_vectors(dev);
507}
508
509/**
510 * pcie_port_probe_service - probe driver for given PCI Express port service
511 * @dev: PCI Express port service device to probe against
512 *
513 * If PCI Express port service driver is registered with
514 * pcie_port_service_register(), this function will be called by the driver core
515 * whenever match is found between the driver and a port service device.
516 */
517static int pcie_port_probe_service(struct device *dev)
518{
519	struct pcie_device *pciedev;
520	struct pcie_port_service_driver *driver;
521	int status;
522
523	if (!dev || !dev->driver)
524		return -ENODEV;
525
526	driver = to_service_driver(dev->driver);
527	if (!driver || !driver->probe)
528		return -ENODEV;
529
530	pciedev = to_pcie_device(dev);
531	status = driver->probe(pciedev);
532	if (status)
533		return status;
534
535	get_device(dev);
536	return 0;
537}
538
539/**
540 * pcie_port_remove_service - detach driver from given PCI Express port service
541 * @dev: PCI Express port service device to handle
542 *
543 * If PCI Express port service driver is registered with
544 * pcie_port_service_register(), this function will be called by the driver core
545 * when device_unregister() is called for the port service device associated
546 * with the driver.
547 */
548static int pcie_port_remove_service(struct device *dev)
549{
550	struct pcie_device *pciedev;
551	struct pcie_port_service_driver *driver;
552
553	if (!dev || !dev->driver)
554		return 0;
555
556	pciedev = to_pcie_device(dev);
557	driver = to_service_driver(dev->driver);
558	if (driver && driver->remove) {
559		driver->remove(pciedev);
560		put_device(dev);
561	}
562	return 0;
563}
564
565/**
566 * pcie_port_shutdown_service - shut down given PCI Express port service
567 * @dev: PCI Express port service device to handle
568 *
569 * If PCI Express port service driver is registered with
570 * pcie_port_service_register(), this function will be called by the driver core
571 * when device_shutdown() is called for the port service device associated
572 * with the driver.
573 */
574static void pcie_port_shutdown_service(struct device *dev) {}
575
576/**
577 * pcie_port_service_register - register PCI Express port service driver
578 * @new: PCI Express port service driver to register
579 */
580int pcie_port_service_register(struct pcie_port_service_driver *new)
581{
582	if (pcie_ports_disabled)
583		return -ENODEV;
584
585	new->driver.name = new->name;
586	new->driver.bus = &pcie_port_bus_type;
587	new->driver.probe = pcie_port_probe_service;
588	new->driver.remove = pcie_port_remove_service;
589	new->driver.shutdown = pcie_port_shutdown_service;
590
591	return driver_register(&new->driver);
592}
593
594/**
595 * pcie_port_service_unregister - unregister PCI Express port service driver
596 * @drv: PCI Express port service driver to unregister
597 */
598void pcie_port_service_unregister(struct pcie_port_service_driver *drv)
599{
600	driver_unregister(&drv->driver);
601}
602
603/* If this switch is set, PCIe port native services should not be enabled. */
604bool pcie_ports_disabled;
605
606/*
607 * If the user specified "pcie_ports=native", use the PCIe services regardless
608 * of whether the platform has given us permission.  On ACPI systems, this
609 * means we ignore _OSC.
610 */
611bool pcie_ports_native;
612
613/*
614 * If the user specified "pcie_ports=dpc-native", use the Linux DPC PCIe
615 * service even if the platform hasn't given us permission.
616 */
617bool pcie_ports_dpc_native;
618
619static int __init pcie_port_setup(char *str)
620{
621	if (!strncmp(str, "compat", 6))
622		pcie_ports_disabled = true;
623	else if (!strncmp(str, "native", 6))
624		pcie_ports_native = true;
625	else if (!strncmp(str, "dpc-native", 10))
626		pcie_ports_dpc_native = true;
627
628	return 1;
629}
630__setup("pcie_ports=", pcie_port_setup);
631
632/* global data */
633
634#ifdef CONFIG_PM
635static int pcie_port_runtime_suspend(struct device *dev)
636{
637	if (!to_pci_dev(dev)->bridge_d3)
638		return -EBUSY;
639
640	return pcie_port_device_runtime_suspend(dev);
641}
642
643static int pcie_port_runtime_idle(struct device *dev)
644{
645	/*
646	 * Assume the PCI core has set bridge_d3 whenever it thinks the port
647	 * should be good to go to D3.  Everything else, including moving
648	 * the port to D3, is handled by the PCI core.
649	 */
650	return to_pci_dev(dev)->bridge_d3 ? 0 : -EBUSY;
651}
652
653static const struct dev_pm_ops pcie_portdrv_pm_ops = {
654	.suspend	= pcie_port_device_suspend,
655	.resume_noirq	= pcie_port_device_resume_noirq,
656	.resume		= pcie_port_device_resume,
657	.freeze		= pcie_port_device_suspend,
658	.thaw		= pcie_port_device_resume,
659	.poweroff	= pcie_port_device_suspend,
660	.restore_noirq	= pcie_port_device_resume_noirq,
661	.restore	= pcie_port_device_resume,
662	.runtime_suspend = pcie_port_runtime_suspend,
663	.runtime_resume	= pcie_port_device_runtime_resume,
664	.runtime_idle	= pcie_port_runtime_idle,
665};
666
667#define PCIE_PORTDRV_PM_OPS	(&pcie_portdrv_pm_ops)
668
669#else /* !PM */
670
671#define PCIE_PORTDRV_PM_OPS	NULL
672#endif /* !PM */
673
674/*
675 * pcie_portdrv_probe - Probe PCI-Express port devices
676 * @dev: PCI-Express port device being probed
677 *
678 * If detected invokes the pcie_port_device_register() method for
679 * this port device.
680 *
681 */
682static int pcie_portdrv_probe(struct pci_dev *dev,
683					const struct pci_device_id *id)
684{
685	int type = pci_pcie_type(dev);
686	int status;
687
688	if (!pci_is_pcie(dev) ||
689	    ((type != PCI_EXP_TYPE_ROOT_PORT) &&
690	     (type != PCI_EXP_TYPE_UPSTREAM) &&
691	     (type != PCI_EXP_TYPE_DOWNSTREAM) &&
692	     (type != PCI_EXP_TYPE_RC_EC)))
693		return -ENODEV;
694
695	if (type == PCI_EXP_TYPE_RC_EC)
696		pcie_link_rcec(dev);
697
698	status = pcie_port_device_register(dev);
699	if (status)
700		return status;
701
702	pci_save_state(dev);
703
704	dev_pm_set_driver_flags(&dev->dev, DPM_FLAG_NO_DIRECT_COMPLETE |
705					   DPM_FLAG_SMART_SUSPEND);
706
707	if (pci_bridge_d3_possible(dev)) {
708		/*
709		 * Keep the port resumed 100ms to make sure things like
710		 * config space accesses from userspace (lspci) will not
711		 * cause the port to repeatedly suspend and resume.
712		 */
713		pm_runtime_set_autosuspend_delay(&dev->dev, 100);
714		pm_runtime_use_autosuspend(&dev->dev);
715		pm_runtime_mark_last_busy(&dev->dev);
716		pm_runtime_put_autosuspend(&dev->dev);
717		pm_runtime_allow(&dev->dev);
718	}
719
720	return 0;
721}
722
723static void pcie_portdrv_remove(struct pci_dev *dev)
724{
725	if (pci_bridge_d3_possible(dev)) {
726		pm_runtime_forbid(&dev->dev);
727		pm_runtime_get_noresume(&dev->dev);
728		pm_runtime_dont_use_autosuspend(&dev->dev);
729	}
730
731	pcie_port_device_remove(dev);
732
733	pci_disable_device(dev);
734}
735
736static void pcie_portdrv_shutdown(struct pci_dev *dev)
737{
738	if (pci_bridge_d3_possible(dev)) {
739		pm_runtime_forbid(&dev->dev);
740		pm_runtime_get_noresume(&dev->dev);
741		pm_runtime_dont_use_autosuspend(&dev->dev);
742	}
743
744	pcie_port_device_remove(dev);
745}
746
747static pci_ers_result_t pcie_portdrv_error_detected(struct pci_dev *dev,
748					pci_channel_state_t error)
749{
750	if (error == pci_channel_io_frozen)
751		return PCI_ERS_RESULT_NEED_RESET;
752	return PCI_ERS_RESULT_CAN_RECOVER;
753}
754
755static pci_ers_result_t pcie_portdrv_slot_reset(struct pci_dev *dev)
756{
757	size_t off = offsetof(struct pcie_port_service_driver, slot_reset);
758	device_for_each_child(&dev->dev, &off, pcie_port_device_iter);
759
760	pci_restore_state(dev);
761	pci_save_state(dev);
762	return PCI_ERS_RESULT_RECOVERED;
763}
764
765static pci_ers_result_t pcie_portdrv_mmio_enabled(struct pci_dev *dev)
766{
767	return PCI_ERS_RESULT_RECOVERED;
768}
769
770/*
771 * LINUX Device Driver Model
772 */
773static const struct pci_device_id port_pci_ids[] = {
774	/* handle any PCI-Express port */
775	{ PCI_DEVICE_CLASS(PCI_CLASS_BRIDGE_PCI_NORMAL, ~0) },
776	/* subtractive decode PCI-to-PCI bridge, class type is 060401h */
777	{ PCI_DEVICE_CLASS(PCI_CLASS_BRIDGE_PCI_SUBTRACTIVE, ~0) },
778	/* handle any Root Complex Event Collector */
779	{ PCI_DEVICE_CLASS(((PCI_CLASS_SYSTEM_RCEC << 8) | 0x00), ~0) },
780	{ },
781};
782
783static const struct pci_error_handlers pcie_portdrv_err_handler = {
784	.error_detected = pcie_portdrv_error_detected,
785	.slot_reset = pcie_portdrv_slot_reset,
786	.mmio_enabled = pcie_portdrv_mmio_enabled,
787};
788
789static struct pci_driver pcie_portdriver = {
790	.name		= "pcieport",
791	.id_table	= port_pci_ids,
792
793	.probe		= pcie_portdrv_probe,
794	.remove		= pcie_portdrv_remove,
795	.shutdown	= pcie_portdrv_shutdown,
796
797	.err_handler	= &pcie_portdrv_err_handler,
798
799	.driver_managed_dma = true,
800
801	.driver.pm	= PCIE_PORTDRV_PM_OPS,
802};
803
804static int __init dmi_pcie_pme_disable_msi(const struct dmi_system_id *d)
805{
806	pr_notice("%s detected: will not use MSI for PCIe PME signaling\n",
807		  d->ident);
808	pcie_pme_disable_msi();
809	return 0;
810}
811
812static const struct dmi_system_id pcie_portdrv_dmi_table[] __initconst = {
813	/*
814	 * Boxes that should not use MSI for PCIe PME signaling.
815	 */
816	{
817	 .callback = dmi_pcie_pme_disable_msi,
818	 .ident = "MSI Wind U-100",
819	 .matches = {
820		     DMI_MATCH(DMI_SYS_VENDOR,
821				"MICRO-STAR INTERNATIONAL CO., LTD"),
822		     DMI_MATCH(DMI_PRODUCT_NAME, "U-100"),
823		     },
824	 },
825	 {}
826};
827
828static void __init pcie_init_services(void)
829{
830	pcie_aer_init();
831	pcie_pme_init();
832	pcie_dpc_init();
833	pcie_bwctrl_init();
834	pcie_hp_init();
835}
836
837static int __init pcie_portdrv_init(void)
838{
839	if (pcie_ports_disabled)
840		return -EACCES;
841
842	pcie_init_services();
843	dmi_check_system(pcie_portdrv_dmi_table);
844
845	return pci_register_driver(&pcie_portdriver);
846}
847device_initcall(pcie_portdrv_init);