xref: /openbmc/linux/drivers/pci/pcie/portdrv.c (revision 7559e757)
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/dmi.h>
10 #include <linux/init.h>
11 #include <linux/module.h>
12 #include <linux/pci.h>
13 #include <linux/kernel.h>
14 #include <linux/errno.h>
15 #include <linux/pm.h>
16 #include <linux/pm_runtime.h>
17 #include <linux/string.h>
18 #include <linux/slab.h>
19 #include <linux/aer.h>
20 
21 #include "../pci.h"
22 #include "portdrv.h"
23 
24 /*
25  * The PCIe Capability Interrupt Message Number (PCIe r3.1, sec 7.8.2) must
26  * be one of the first 32 MSI-X entries.  Per PCI r3.0, sec 6.8.3.1, MSI
27  * supports a maximum of 32 vectors per function.
28  */
29 #define PCIE_PORT_MAX_MSI_ENTRIES	32
30 
31 #define get_descriptor_id(type, service) (((type - 4) << 8) | service)
32 
33 struct portdrv_service_data {
34 	struct pcie_port_service_driver *drv;
35 	struct device *dev;
36 	u32 service;
37 };
38 
39 /**
40  * release_pcie_device - free PCI Express port service device structure
41  * @dev: Port service device to release
42  *
43  * Invoked automatically when device is being removed in response to
44  * device_unregister(dev).  Release all resources being claimed.
45  */
46 static void release_pcie_device(struct device *dev)
47 {
48 	kfree(to_pcie_device(dev));
49 }
50 
51 /*
52  * Fill in *pme, *aer, *dpc with the relevant Interrupt Message Numbers if
53  * services are enabled in "mask".  Return the number of MSI/MSI-X vectors
54  * required to accommodate the largest Message Number.
55  */
56 static int pcie_message_numbers(struct pci_dev *dev, int mask,
57 				u32 *pme, u32 *aer, u32 *dpc)
58 {
59 	u32 nvec = 0, pos;
60 	u16 reg16;
61 
62 	/*
63 	 * The Interrupt Message Number indicates which vector is used, i.e.,
64 	 * the MSI-X table entry or the MSI offset between the base Message
65 	 * Data and the generated interrupt message.  See PCIe r3.1, sec
66 	 * 7.8.2, 7.10.10, 7.31.2.
67 	 */
68 
69 	if (mask & (PCIE_PORT_SERVICE_PME | PCIE_PORT_SERVICE_HP |
70 		    PCIE_PORT_SERVICE_BWNOTIF)) {
71 		pcie_capability_read_word(dev, PCI_EXP_FLAGS, &reg16);
72 		*pme = (reg16 & PCI_EXP_FLAGS_IRQ) >> 9;
73 		nvec = *pme + 1;
74 	}
75 
76 #ifdef CONFIG_PCIEAER
77 	if (mask & PCIE_PORT_SERVICE_AER) {
78 		u32 reg32;
79 
80 		pos = dev->aer_cap;
81 		if (pos) {
82 			pci_read_config_dword(dev, pos + PCI_ERR_ROOT_STATUS,
83 					      &reg32);
84 			*aer = (reg32 & PCI_ERR_ROOT_AER_IRQ) >> 27;
85 			nvec = max(nvec, *aer + 1);
86 		}
87 	}
88 #endif
89 
90 	if (mask & PCIE_PORT_SERVICE_DPC) {
91 		pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_DPC);
92 		if (pos) {
93 			pci_read_config_word(dev, pos + PCI_EXP_DPC_CAP,
94 					     &reg16);
95 			*dpc = reg16 & PCI_EXP_DPC_IRQ;
96 			nvec = max(nvec, *dpc + 1);
97 		}
98 	}
99 
100 	return nvec;
101 }
102 
103 /**
104  * pcie_port_enable_irq_vec - try to set up MSI-X or MSI as interrupt mode
105  * for given port
106  * @dev: PCI Express port to handle
107  * @irqs: Array of interrupt vectors to populate
108  * @mask: Bitmask of port capabilities returned by get_port_device_capability()
109  *
110  * Return value: 0 on success, error code on failure
111  */
112 static int pcie_port_enable_irq_vec(struct pci_dev *dev, int *irqs, int mask)
113 {
114 	int nr_entries, nvec, pcie_irq;
115 	u32 pme = 0, aer = 0, dpc = 0;
116 
117 	/* Allocate the maximum possible number of MSI/MSI-X vectors */
118 	nr_entries = pci_alloc_irq_vectors(dev, 1, PCIE_PORT_MAX_MSI_ENTRIES,
119 			PCI_IRQ_MSIX | PCI_IRQ_MSI);
120 	if (nr_entries < 0)
121 		return nr_entries;
122 
123 	/* See how many and which Interrupt Message Numbers we actually use */
124 	nvec = pcie_message_numbers(dev, mask, &pme, &aer, &dpc);
125 	if (nvec > nr_entries) {
126 		pci_free_irq_vectors(dev);
127 		return -EIO;
128 	}
129 
130 	/*
131 	 * If we allocated more than we need, free them and reallocate fewer.
132 	 *
133 	 * Reallocating may change the specific vectors we get, so
134 	 * pci_irq_vector() must be done *after* the reallocation.
135 	 *
136 	 * If we're using MSI, hardware is *allowed* to change the Interrupt
137 	 * Message Numbers when we free and reallocate the vectors, but we
138 	 * assume it won't because we allocate enough vectors for the
139 	 * biggest Message Number we found.
140 	 */
141 	if (nvec != nr_entries) {
142 		pci_free_irq_vectors(dev);
143 
144 		nr_entries = pci_alloc_irq_vectors(dev, nvec, nvec,
145 				PCI_IRQ_MSIX | PCI_IRQ_MSI);
146 		if (nr_entries < 0)
147 			return nr_entries;
148 	}
149 
150 	/* PME, hotplug and bandwidth notification share an MSI/MSI-X vector */
151 	if (mask & (PCIE_PORT_SERVICE_PME | PCIE_PORT_SERVICE_HP |
152 		    PCIE_PORT_SERVICE_BWNOTIF)) {
153 		pcie_irq = pci_irq_vector(dev, pme);
154 		irqs[PCIE_PORT_SERVICE_PME_SHIFT] = pcie_irq;
155 		irqs[PCIE_PORT_SERVICE_HP_SHIFT] = pcie_irq;
156 		irqs[PCIE_PORT_SERVICE_BWNOTIF_SHIFT] = pcie_irq;
157 	}
158 
159 	if (mask & PCIE_PORT_SERVICE_AER)
160 		irqs[PCIE_PORT_SERVICE_AER_SHIFT] = pci_irq_vector(dev, aer);
161 
162 	if (mask & PCIE_PORT_SERVICE_DPC)
163 		irqs[PCIE_PORT_SERVICE_DPC_SHIFT] = pci_irq_vector(dev, dpc);
164 
165 	return 0;
166 }
167 
168 /**
169  * pcie_init_service_irqs - initialize irqs for PCI Express port services
170  * @dev: PCI Express port to handle
171  * @irqs: Array of irqs to populate
172  * @mask: Bitmask of port capabilities returned by get_port_device_capability()
173  *
174  * Return value: Interrupt mode associated with the port
175  */
176 static int pcie_init_service_irqs(struct pci_dev *dev, int *irqs, int mask)
177 {
178 	int ret, i;
179 
180 	for (i = 0; i < PCIE_PORT_DEVICE_MAXSERVICES; i++)
181 		irqs[i] = -1;
182 
183 	/*
184 	 * If we support PME but can't use MSI/MSI-X for it, we have to
185 	 * fall back to INTx or other interrupts, e.g., a system shared
186 	 * interrupt.
187 	 */
188 	if ((mask & PCIE_PORT_SERVICE_PME) && pcie_pme_no_msi())
189 		goto legacy_irq;
190 
191 	/* Try to use MSI-X or MSI if supported */
192 	if (pcie_port_enable_irq_vec(dev, irqs, mask) == 0)
193 		return 0;
194 
195 legacy_irq:
196 	/* fall back to legacy IRQ */
197 	ret = pci_alloc_irq_vectors(dev, 1, 1, PCI_IRQ_LEGACY);
198 	if (ret < 0)
199 		return -ENODEV;
200 
201 	for (i = 0; i < PCIE_PORT_DEVICE_MAXSERVICES; i++)
202 		irqs[i] = pci_irq_vector(dev, 0);
203 
204 	return 0;
205 }
206 
207 /**
208  * get_port_device_capability - discover capabilities of a PCI Express port
209  * @dev: PCI Express port to examine
210  *
211  * The capabilities are read from the port's PCI Express configuration registers
212  * as described in PCI Express Base Specification 1.0a sections 7.8.2, 7.8.9 and
213  * 7.9 - 7.11.
214  *
215  * Return value: Bitmask of discovered port capabilities
216  */
217 static int get_port_device_capability(struct pci_dev *dev)
218 {
219 	struct pci_host_bridge *host = pci_find_host_bridge(dev->bus);
220 	int services = 0;
221 
222 	if (dev->is_hotplug_bridge &&
223 	    (pci_pcie_type(dev) == PCI_EXP_TYPE_ROOT_PORT ||
224 	     pci_pcie_type(dev) == PCI_EXP_TYPE_DOWNSTREAM) &&
225 	    (pcie_ports_native || host->native_pcie_hotplug)) {
226 		services |= PCIE_PORT_SERVICE_HP;
227 
228 		/*
229 		 * Disable hot-plug interrupts in case they have been enabled
230 		 * by the BIOS and the hot-plug service driver is not loaded.
231 		 */
232 		pcie_capability_clear_word(dev, PCI_EXP_SLTCTL,
233 			  PCI_EXP_SLTCTL_CCIE | PCI_EXP_SLTCTL_HPIE);
234 	}
235 
236 #ifdef CONFIG_PCIEAER
237 	if ((pci_pcie_type(dev) == PCI_EXP_TYPE_ROOT_PORT ||
238              pci_pcie_type(dev) == PCI_EXP_TYPE_RC_EC) &&
239 	    dev->aer_cap && pci_aer_available() &&
240 	    (pcie_ports_native || host->native_aer))
241 		services |= PCIE_PORT_SERVICE_AER;
242 #endif
243 
244 	/* Root Ports and Root Complex Event Collectors may generate PMEs */
245 	if ((pci_pcie_type(dev) == PCI_EXP_TYPE_ROOT_PORT ||
246 	     pci_pcie_type(dev) == PCI_EXP_TYPE_RC_EC) &&
247 	    (pcie_ports_native || host->native_pme)) {
248 		services |= PCIE_PORT_SERVICE_PME;
249 
250 		/*
251 		 * Disable PME interrupt on this port in case it's been enabled
252 		 * by the BIOS (the PME service driver will enable it when
253 		 * necessary).
254 		 */
255 		pcie_pme_interrupt_enable(dev, false);
256 	}
257 
258 	/*
259 	 * With dpc-native, allow Linux to use DPC even if it doesn't have
260 	 * permission to use AER.
261 	 */
262 	if (pci_find_ext_capability(dev, PCI_EXT_CAP_ID_DPC) &&
263 	    pci_aer_available() &&
264 	    (pcie_ports_dpc_native || (services & PCIE_PORT_SERVICE_AER)))
265 		services |= PCIE_PORT_SERVICE_DPC;
266 
267 	if (pci_pcie_type(dev) == PCI_EXP_TYPE_DOWNSTREAM ||
268 	    pci_pcie_type(dev) == PCI_EXP_TYPE_ROOT_PORT) {
269 		u32 linkcap;
270 
271 		pcie_capability_read_dword(dev, PCI_EXP_LNKCAP, &linkcap);
272 		if (linkcap & PCI_EXP_LNKCAP_LBNC)
273 			services |= PCIE_PORT_SERVICE_BWNOTIF;
274 	}
275 
276 	return services;
277 }
278 
279 /**
280  * pcie_device_init - allocate and initialize PCI Express port service device
281  * @pdev: PCI Express port to associate the service device with
282  * @service: Type of service to associate with the service device
283  * @irq: Interrupt vector to associate with the service device
284  */
285 static int pcie_device_init(struct pci_dev *pdev, int service, int irq)
286 {
287 	int retval;
288 	struct pcie_device *pcie;
289 	struct device *device;
290 
291 	pcie = kzalloc(sizeof(*pcie), GFP_KERNEL);
292 	if (!pcie)
293 		return -ENOMEM;
294 	pcie->port = pdev;
295 	pcie->irq = irq;
296 	pcie->service = service;
297 
298 	/* Initialize generic device interface */
299 	device = &pcie->device;
300 	device->bus = &pcie_port_bus_type;
301 	device->release = release_pcie_device;	/* callback to free pcie dev */
302 	dev_set_name(device, "%s:pcie%03x",
303 		     pci_name(pdev),
304 		     get_descriptor_id(pci_pcie_type(pdev), service));
305 	device->parent = &pdev->dev;
306 	device_enable_async_suspend(device);
307 
308 	retval = device_register(device);
309 	if (retval) {
310 		put_device(device);
311 		return retval;
312 	}
313 
314 	pm_runtime_no_callbacks(device);
315 
316 	return 0;
317 }
318 
319 /**
320  * pcie_port_device_register - register PCI Express port
321  * @dev: PCI Express port to register
322  *
323  * Allocate the port extension structure and register services associated with
324  * the port.
325  */
326 static int pcie_port_device_register(struct pci_dev *dev)
327 {
328 	int status, capabilities, i, nr_service;
329 	int irqs[PCIE_PORT_DEVICE_MAXSERVICES];
330 
331 	/* Enable PCI Express port device */
332 	status = pci_enable_device(dev);
333 	if (status)
334 		return status;
335 
336 	/* Get and check PCI Express port services */
337 	capabilities = get_port_device_capability(dev);
338 	if (!capabilities)
339 		return 0;
340 
341 	pci_set_master(dev);
342 	/*
343 	 * Initialize service irqs. Don't use service devices that
344 	 * require interrupts if there is no way to generate them.
345 	 * However, some drivers may have a polling mode (e.g. pciehp_poll_mode)
346 	 * that can be used in the absence of irqs.  Allow them to determine
347 	 * if that is to be used.
348 	 */
349 	status = pcie_init_service_irqs(dev, irqs, capabilities);
350 	if (status) {
351 		capabilities &= PCIE_PORT_SERVICE_HP;
352 		if (!capabilities)
353 			goto error_disable;
354 	}
355 
356 	/* Allocate child services if any */
357 	status = -ENODEV;
358 	nr_service = 0;
359 	for (i = 0; i < PCIE_PORT_DEVICE_MAXSERVICES; i++) {
360 		int service = 1 << i;
361 		if (!(capabilities & service))
362 			continue;
363 		if (!pcie_device_init(dev, service, irqs[i]))
364 			nr_service++;
365 	}
366 	if (!nr_service)
367 		goto error_cleanup_irqs;
368 
369 	return 0;
370 
371 error_cleanup_irqs:
372 	pci_free_irq_vectors(dev);
373 error_disable:
374 	pci_disable_device(dev);
375 	return status;
376 }
377 
378 typedef int (*pcie_callback_t)(struct pcie_device *);
379 
380 static int pcie_port_device_iter(struct device *dev, void *data)
381 {
382 	struct pcie_port_service_driver *service_driver;
383 	size_t offset = *(size_t *)data;
384 	pcie_callback_t cb;
385 
386 	if ((dev->bus == &pcie_port_bus_type) && dev->driver) {
387 		service_driver = to_service_driver(dev->driver);
388 		cb = *(pcie_callback_t *)((void *)service_driver + offset);
389 		if (cb)
390 			return cb(to_pcie_device(dev));
391 	}
392 	return 0;
393 }
394 
395 #ifdef CONFIG_PM
396 /**
397  * pcie_port_device_suspend - suspend port services associated with a PCIe port
398  * @dev: PCI Express port to handle
399  */
400 static int pcie_port_device_suspend(struct device *dev)
401 {
402 	size_t off = offsetof(struct pcie_port_service_driver, suspend);
403 	return device_for_each_child(dev, &off, pcie_port_device_iter);
404 }
405 
406 static int pcie_port_device_resume_noirq(struct device *dev)
407 {
408 	size_t off = offsetof(struct pcie_port_service_driver, resume_noirq);
409 	return device_for_each_child(dev, &off, pcie_port_device_iter);
410 }
411 
412 /**
413  * pcie_port_device_resume - resume port services associated with a PCIe port
414  * @dev: PCI Express port to handle
415  */
416 static int pcie_port_device_resume(struct device *dev)
417 {
418 	size_t off = offsetof(struct pcie_port_service_driver, resume);
419 	return device_for_each_child(dev, &off, pcie_port_device_iter);
420 }
421 
422 /**
423  * pcie_port_device_runtime_suspend - runtime suspend port services
424  * @dev: PCI Express port to handle
425  */
426 static int pcie_port_device_runtime_suspend(struct device *dev)
427 {
428 	size_t off = offsetof(struct pcie_port_service_driver, runtime_suspend);
429 	return device_for_each_child(dev, &off, pcie_port_device_iter);
430 }
431 
432 /**
433  * pcie_port_device_runtime_resume - runtime resume port services
434  * @dev: PCI Express port to handle
435  */
436 static int pcie_port_device_runtime_resume(struct device *dev)
437 {
438 	size_t off = offsetof(struct pcie_port_service_driver, runtime_resume);
439 	return device_for_each_child(dev, &off, pcie_port_device_iter);
440 }
441 #endif /* PM */
442 
443 static int remove_iter(struct device *dev, void *data)
444 {
445 	if (dev->bus == &pcie_port_bus_type)
446 		device_unregister(dev);
447 	return 0;
448 }
449 
450 static int find_service_iter(struct device *device, void *data)
451 {
452 	struct pcie_port_service_driver *service_driver;
453 	struct portdrv_service_data *pdrvs;
454 	u32 service;
455 
456 	pdrvs = (struct portdrv_service_data *) data;
457 	service = pdrvs->service;
458 
459 	if (device->bus == &pcie_port_bus_type && device->driver) {
460 		service_driver = to_service_driver(device->driver);
461 		if (service_driver->service == service) {
462 			pdrvs->drv = service_driver;
463 			pdrvs->dev = device;
464 			return 1;
465 		}
466 	}
467 
468 	return 0;
469 }
470 
471 /**
472  * pcie_port_find_device - find the struct device
473  * @dev: PCI Express port the service is associated with
474  * @service: For the service to find
475  *
476  * Find the struct device associated with given service on a pci_dev
477  */
478 struct device *pcie_port_find_device(struct pci_dev *dev,
479 				      u32 service)
480 {
481 	struct device *device;
482 	struct portdrv_service_data pdrvs;
483 
484 	pdrvs.dev = NULL;
485 	pdrvs.service = service;
486 	device_for_each_child(&dev->dev, &pdrvs, find_service_iter);
487 
488 	device = pdrvs.dev;
489 	return device;
490 }
491 EXPORT_SYMBOL_GPL(pcie_port_find_device);
492 
493 /**
494  * pcie_port_device_remove - unregister PCI Express port service devices
495  * @dev: PCI Express port the service devices to unregister are associated with
496  *
497  * Remove PCI Express port service devices associated with given port and
498  * disable MSI-X or MSI for the port.
499  */
500 static void pcie_port_device_remove(struct pci_dev *dev)
501 {
502 	device_for_each_child(&dev->dev, NULL, remove_iter);
503 	pci_free_irq_vectors(dev);
504 }
505 
506 /**
507  * pcie_port_probe_service - probe driver for given PCI Express port service
508  * @dev: PCI Express port service device to probe against
509  *
510  * If PCI Express port service driver is registered with
511  * pcie_port_service_register(), this function will be called by the driver core
512  * whenever match is found between the driver and a port service device.
513  */
514 static int pcie_port_probe_service(struct device *dev)
515 {
516 	struct pcie_device *pciedev;
517 	struct pcie_port_service_driver *driver;
518 	int status;
519 
520 	if (!dev || !dev->driver)
521 		return -ENODEV;
522 
523 	driver = to_service_driver(dev->driver);
524 	if (!driver || !driver->probe)
525 		return -ENODEV;
526 
527 	pciedev = to_pcie_device(dev);
528 	status = driver->probe(pciedev);
529 	if (status)
530 		return status;
531 
532 	get_device(dev);
533 	return 0;
534 }
535 
536 /**
537  * pcie_port_remove_service - detach driver from given PCI Express port service
538  * @dev: PCI Express port service device to handle
539  *
540  * If PCI Express port service driver is registered with
541  * pcie_port_service_register(), this function will be called by the driver core
542  * when device_unregister() is called for the port service device associated
543  * with the driver.
544  */
545 static int pcie_port_remove_service(struct device *dev)
546 {
547 	struct pcie_device *pciedev;
548 	struct pcie_port_service_driver *driver;
549 
550 	if (!dev || !dev->driver)
551 		return 0;
552 
553 	pciedev = to_pcie_device(dev);
554 	driver = to_service_driver(dev->driver);
555 	if (driver && driver->remove) {
556 		driver->remove(pciedev);
557 		put_device(dev);
558 	}
559 	return 0;
560 }
561 
562 /**
563  * pcie_port_shutdown_service - shut down given PCI Express port service
564  * @dev: PCI Express port service device to handle
565  *
566  * If PCI Express port service driver is registered with
567  * pcie_port_service_register(), this function will be called by the driver core
568  * when device_shutdown() is called for the port service device associated
569  * with the driver.
570  */
571 static void pcie_port_shutdown_service(struct device *dev) {}
572 
573 /**
574  * pcie_port_service_register - register PCI Express port service driver
575  * @new: PCI Express port service driver to register
576  */
577 int pcie_port_service_register(struct pcie_port_service_driver *new)
578 {
579 	if (pcie_ports_disabled)
580 		return -ENODEV;
581 
582 	new->driver.name = new->name;
583 	new->driver.bus = &pcie_port_bus_type;
584 	new->driver.probe = pcie_port_probe_service;
585 	new->driver.remove = pcie_port_remove_service;
586 	new->driver.shutdown = pcie_port_shutdown_service;
587 
588 	return driver_register(&new->driver);
589 }
590 
591 /**
592  * pcie_port_service_unregister - unregister PCI Express port service driver
593  * @drv: PCI Express port service driver to unregister
594  */
595 void pcie_port_service_unregister(struct pcie_port_service_driver *drv)
596 {
597 	driver_unregister(&drv->driver);
598 }
599 
600 /* If this switch is set, PCIe port native services should not be enabled. */
601 bool pcie_ports_disabled;
602 
603 /*
604  * If the user specified "pcie_ports=native", use the PCIe services regardless
605  * of whether the platform has given us permission.  On ACPI systems, this
606  * means we ignore _OSC.
607  */
608 bool pcie_ports_native;
609 
610 /*
611  * If the user specified "pcie_ports=dpc-native", use the Linux DPC PCIe
612  * service even if the platform hasn't given us permission.
613  */
614 bool pcie_ports_dpc_native;
615 
616 static int __init pcie_port_setup(char *str)
617 {
618 	if (!strncmp(str, "compat", 6))
619 		pcie_ports_disabled = true;
620 	else if (!strncmp(str, "native", 6))
621 		pcie_ports_native = true;
622 	else if (!strncmp(str, "dpc-native", 10))
623 		pcie_ports_dpc_native = true;
624 
625 	return 1;
626 }
627 __setup("pcie_ports=", pcie_port_setup);
628 
629 /* global data */
630 
631 #ifdef CONFIG_PM
632 static int pcie_port_runtime_suspend(struct device *dev)
633 {
634 	if (!to_pci_dev(dev)->bridge_d3)
635 		return -EBUSY;
636 
637 	return pcie_port_device_runtime_suspend(dev);
638 }
639 
640 static int pcie_port_runtime_idle(struct device *dev)
641 {
642 	/*
643 	 * Assume the PCI core has set bridge_d3 whenever it thinks the port
644 	 * should be good to go to D3.  Everything else, including moving
645 	 * the port to D3, is handled by the PCI core.
646 	 */
647 	return to_pci_dev(dev)->bridge_d3 ? 0 : -EBUSY;
648 }
649 
650 static const struct dev_pm_ops pcie_portdrv_pm_ops = {
651 	.suspend	= pcie_port_device_suspend,
652 	.resume_noirq	= pcie_port_device_resume_noirq,
653 	.resume		= pcie_port_device_resume,
654 	.freeze		= pcie_port_device_suspend,
655 	.thaw		= pcie_port_device_resume,
656 	.poweroff	= pcie_port_device_suspend,
657 	.restore_noirq	= pcie_port_device_resume_noirq,
658 	.restore	= pcie_port_device_resume,
659 	.runtime_suspend = pcie_port_runtime_suspend,
660 	.runtime_resume	= pcie_port_device_runtime_resume,
661 	.runtime_idle	= pcie_port_runtime_idle,
662 };
663 
664 #define PCIE_PORTDRV_PM_OPS	(&pcie_portdrv_pm_ops)
665 
666 #else /* !PM */
667 
668 #define PCIE_PORTDRV_PM_OPS	NULL
669 #endif /* !PM */
670 
671 /*
672  * pcie_portdrv_probe - Probe PCI-Express port devices
673  * @dev: PCI-Express port device being probed
674  *
675  * If detected invokes the pcie_port_device_register() method for
676  * this port device.
677  *
678  */
679 static int pcie_portdrv_probe(struct pci_dev *dev,
680 					const struct pci_device_id *id)
681 {
682 	int type = pci_pcie_type(dev);
683 	int status;
684 
685 	if (!pci_is_pcie(dev) ||
686 	    ((type != PCI_EXP_TYPE_ROOT_PORT) &&
687 	     (type != PCI_EXP_TYPE_UPSTREAM) &&
688 	     (type != PCI_EXP_TYPE_DOWNSTREAM) &&
689 	     (type != PCI_EXP_TYPE_RC_EC)))
690 		return -ENODEV;
691 
692 	if (type == PCI_EXP_TYPE_RC_EC)
693 		pcie_link_rcec(dev);
694 
695 	status = pcie_port_device_register(dev);
696 	if (status)
697 		return status;
698 
699 	pci_save_state(dev);
700 
701 	dev_pm_set_driver_flags(&dev->dev, DPM_FLAG_NO_DIRECT_COMPLETE |
702 					   DPM_FLAG_SMART_SUSPEND);
703 
704 	if (pci_bridge_d3_possible(dev)) {
705 		/*
706 		 * Keep the port resumed 100ms to make sure things like
707 		 * config space accesses from userspace (lspci) will not
708 		 * cause the port to repeatedly suspend and resume.
709 		 */
710 		pm_runtime_set_autosuspend_delay(&dev->dev, 100);
711 		pm_runtime_use_autosuspend(&dev->dev);
712 		pm_runtime_mark_last_busy(&dev->dev);
713 		pm_runtime_put_autosuspend(&dev->dev);
714 		pm_runtime_allow(&dev->dev);
715 	}
716 
717 	return 0;
718 }
719 
720 static void pcie_portdrv_remove(struct pci_dev *dev)
721 {
722 	if (pci_bridge_d3_possible(dev)) {
723 		pm_runtime_forbid(&dev->dev);
724 		pm_runtime_get_noresume(&dev->dev);
725 		pm_runtime_dont_use_autosuspend(&dev->dev);
726 	}
727 
728 	pcie_port_device_remove(dev);
729 
730 	pci_disable_device(dev);
731 }
732 
733 static void pcie_portdrv_shutdown(struct pci_dev *dev)
734 {
735 	if (pci_bridge_d3_possible(dev)) {
736 		pm_runtime_forbid(&dev->dev);
737 		pm_runtime_get_noresume(&dev->dev);
738 		pm_runtime_dont_use_autosuspend(&dev->dev);
739 	}
740 
741 	pcie_port_device_remove(dev);
742 }
743 
744 static pci_ers_result_t pcie_portdrv_error_detected(struct pci_dev *dev,
745 					pci_channel_state_t error)
746 {
747 	if (error == pci_channel_io_frozen)
748 		return PCI_ERS_RESULT_NEED_RESET;
749 	return PCI_ERS_RESULT_CAN_RECOVER;
750 }
751 
752 static pci_ers_result_t pcie_portdrv_slot_reset(struct pci_dev *dev)
753 {
754 	size_t off = offsetof(struct pcie_port_service_driver, slot_reset);
755 	device_for_each_child(&dev->dev, &off, pcie_port_device_iter);
756 
757 	pci_restore_state(dev);
758 	pci_save_state(dev);
759 	return PCI_ERS_RESULT_RECOVERED;
760 }
761 
762 static pci_ers_result_t pcie_portdrv_mmio_enabled(struct pci_dev *dev)
763 {
764 	return PCI_ERS_RESULT_RECOVERED;
765 }
766 
767 /*
768  * LINUX Device Driver Model
769  */
770 static const struct pci_device_id port_pci_ids[] = {
771 	/* handle any PCI-Express port */
772 	{ PCI_DEVICE_CLASS(PCI_CLASS_BRIDGE_PCI_NORMAL, ~0) },
773 	/* subtractive decode PCI-to-PCI bridge, class type is 060401h */
774 	{ PCI_DEVICE_CLASS(PCI_CLASS_BRIDGE_PCI_SUBTRACTIVE, ~0) },
775 	/* handle any Root Complex Event Collector */
776 	{ PCI_DEVICE_CLASS(((PCI_CLASS_SYSTEM_RCEC << 8) | 0x00), ~0) },
777 	{ },
778 };
779 
780 static const struct pci_error_handlers pcie_portdrv_err_handler = {
781 	.error_detected = pcie_portdrv_error_detected,
782 	.slot_reset = pcie_portdrv_slot_reset,
783 	.mmio_enabled = pcie_portdrv_mmio_enabled,
784 };
785 
786 static struct pci_driver pcie_portdriver = {
787 	.name		= "pcieport",
788 	.id_table	= &port_pci_ids[0],
789 
790 	.probe		= pcie_portdrv_probe,
791 	.remove		= pcie_portdrv_remove,
792 	.shutdown	= pcie_portdrv_shutdown,
793 
794 	.err_handler	= &pcie_portdrv_err_handler,
795 
796 	.driver_managed_dma = true,
797 
798 	.driver.pm	= PCIE_PORTDRV_PM_OPS,
799 };
800 
801 static int __init dmi_pcie_pme_disable_msi(const struct dmi_system_id *d)
802 {
803 	pr_notice("%s detected: will not use MSI for PCIe PME signaling\n",
804 		  d->ident);
805 	pcie_pme_disable_msi();
806 	return 0;
807 }
808 
809 static const struct dmi_system_id pcie_portdrv_dmi_table[] __initconst = {
810 	/*
811 	 * Boxes that should not use MSI for PCIe PME signaling.
812 	 */
813 	{
814 	 .callback = dmi_pcie_pme_disable_msi,
815 	 .ident = "MSI Wind U-100",
816 	 .matches = {
817 		     DMI_MATCH(DMI_SYS_VENDOR,
818 				"MICRO-STAR INTERNATIONAL CO., LTD"),
819 		     DMI_MATCH(DMI_PRODUCT_NAME, "U-100"),
820 		     },
821 	 },
822 	 {}
823 };
824 
825 static void __init pcie_init_services(void)
826 {
827 	pcie_aer_init();
828 	pcie_pme_init();
829 	pcie_dpc_init();
830 	pcie_hp_init();
831 }
832 
833 static int __init pcie_portdrv_init(void)
834 {
835 	if (pcie_ports_disabled)
836 		return -EACCES;
837 
838 	pcie_init_services();
839 	dmi_check_system(pcie_portdrv_dmi_table);
840 
841 	return pci_register_driver(&pcie_portdriver);
842 }
843 device_initcall(pcie_portdrv_init);
844