xref: /openbmc/linux/drivers/pci/pcie/aer.c (revision 78560d41)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Implement the AER root port service driver. The driver registers an IRQ
4  * handler. When a root port triggers an AER interrupt, the IRQ handler
5  * collects root port status and schedules work.
6  *
7  * Copyright (C) 2006 Intel Corp.
8  *	Tom Long Nguyen (tom.l.nguyen@intel.com)
9  *	Zhang Yanmin (yanmin.zhang@intel.com)
10  *
11  * (C) Copyright 2009 Hewlett-Packard Development Company, L.P.
12  *    Andrew Patterson <andrew.patterson@hp.com>
13  */
14 
15 #define pr_fmt(fmt) "AER: " fmt
16 #define dev_fmt pr_fmt
17 
18 #include <linux/bitops.h>
19 #include <linux/cper.h>
20 #include <linux/pci.h>
21 #include <linux/pci-acpi.h>
22 #include <linux/sched.h>
23 #include <linux/kernel.h>
24 #include <linux/errno.h>
25 #include <linux/pm.h>
26 #include <linux/init.h>
27 #include <linux/interrupt.h>
28 #include <linux/delay.h>
29 #include <linux/kfifo.h>
30 #include <linux/slab.h>
31 #include <acpi/apei.h>
32 #include <ras/ras_event.h>
33 
34 #include "../pci.h"
35 #include "portdrv.h"
36 
37 #define AER_ERROR_SOURCES_MAX		128
38 
39 #define AER_MAX_TYPEOF_COR_ERRS		16	/* as per PCI_ERR_COR_STATUS */
40 #define AER_MAX_TYPEOF_UNCOR_ERRS	27	/* as per PCI_ERR_UNCOR_STATUS*/
41 
42 struct aer_err_source {
43 	unsigned int status;
44 	unsigned int id;
45 };
46 
47 struct aer_rpc {
48 	struct pci_dev *rpd;		/* Root Port device */
49 	DECLARE_KFIFO(aer_fifo, struct aer_err_source, AER_ERROR_SOURCES_MAX);
50 };
51 
52 /* AER stats for the device */
53 struct aer_stats {
54 
55 	/*
56 	 * Fields for all AER capable devices. They indicate the errors
57 	 * "as seen by this device". Note that this may mean that if an
58 	 * end point is causing problems, the AER counters may increment
59 	 * at its link partner (e.g. root port) because the errors will be
60 	 * "seen" by the link partner and not the the problematic end point
61 	 * itself (which may report all counters as 0 as it never saw any
62 	 * problems).
63 	 */
64 	/* Counters for different type of correctable errors */
65 	u64 dev_cor_errs[AER_MAX_TYPEOF_COR_ERRS];
66 	/* Counters for different type of fatal uncorrectable errors */
67 	u64 dev_fatal_errs[AER_MAX_TYPEOF_UNCOR_ERRS];
68 	/* Counters for different type of nonfatal uncorrectable errors */
69 	u64 dev_nonfatal_errs[AER_MAX_TYPEOF_UNCOR_ERRS];
70 	/* Total number of ERR_COR sent by this device */
71 	u64 dev_total_cor_errs;
72 	/* Total number of ERR_FATAL sent by this device */
73 	u64 dev_total_fatal_errs;
74 	/* Total number of ERR_NONFATAL sent by this device */
75 	u64 dev_total_nonfatal_errs;
76 
77 	/*
78 	 * Fields for Root ports & root complex event collectors only, these
79 	 * indicate the total number of ERR_COR, ERR_FATAL, and ERR_NONFATAL
80 	 * messages received by the root port / event collector, INCLUDING the
81 	 * ones that are generated internally (by the rootport itself)
82 	 */
83 	u64 rootport_total_cor_errs;
84 	u64 rootport_total_fatal_errs;
85 	u64 rootport_total_nonfatal_errs;
86 };
87 
88 #define AER_LOG_TLP_MASKS		(PCI_ERR_UNC_POISON_TLP|	\
89 					PCI_ERR_UNC_ECRC|		\
90 					PCI_ERR_UNC_UNSUP|		\
91 					PCI_ERR_UNC_COMP_ABORT|		\
92 					PCI_ERR_UNC_UNX_COMP|		\
93 					PCI_ERR_UNC_MALF_TLP)
94 
95 #define SYSTEM_ERROR_INTR_ON_MESG_MASK	(PCI_EXP_RTCTL_SECEE|	\
96 					PCI_EXP_RTCTL_SENFEE|	\
97 					PCI_EXP_RTCTL_SEFEE)
98 #define ROOT_PORT_INTR_ON_MESG_MASK	(PCI_ERR_ROOT_CMD_COR_EN|	\
99 					PCI_ERR_ROOT_CMD_NONFATAL_EN|	\
100 					PCI_ERR_ROOT_CMD_FATAL_EN)
101 #define ERR_COR_ID(d)			(d & 0xffff)
102 #define ERR_UNCOR_ID(d)			(d >> 16)
103 
104 static int pcie_aer_disable;
105 
106 void pci_no_aer(void)
107 {
108 	pcie_aer_disable = 1;
109 }
110 
111 bool pci_aer_available(void)
112 {
113 	return !pcie_aer_disable && pci_msi_enabled();
114 }
115 
116 #ifdef CONFIG_PCIE_ECRC
117 
118 #define ECRC_POLICY_DEFAULT 0		/* ECRC set by BIOS */
119 #define ECRC_POLICY_OFF     1		/* ECRC off for performance */
120 #define ECRC_POLICY_ON      2		/* ECRC on for data integrity */
121 
122 static int ecrc_policy = ECRC_POLICY_DEFAULT;
123 
124 static const char * const ecrc_policy_str[] = {
125 	[ECRC_POLICY_DEFAULT] = "bios",
126 	[ECRC_POLICY_OFF] = "off",
127 	[ECRC_POLICY_ON] = "on"
128 };
129 
130 /**
131  * enable_ercr_checking - enable PCIe ECRC checking for a device
132  * @dev: the PCI device
133  *
134  * Returns 0 on success, or negative on failure.
135  */
136 static int enable_ecrc_checking(struct pci_dev *dev)
137 {
138 	int pos;
139 	u32 reg32;
140 
141 	if (!pci_is_pcie(dev))
142 		return -ENODEV;
143 
144 	pos = dev->aer_cap;
145 	if (!pos)
146 		return -ENODEV;
147 
148 	pci_read_config_dword(dev, pos + PCI_ERR_CAP, &reg32);
149 	if (reg32 & PCI_ERR_CAP_ECRC_GENC)
150 		reg32 |= PCI_ERR_CAP_ECRC_GENE;
151 	if (reg32 & PCI_ERR_CAP_ECRC_CHKC)
152 		reg32 |= PCI_ERR_CAP_ECRC_CHKE;
153 	pci_write_config_dword(dev, pos + PCI_ERR_CAP, reg32);
154 
155 	return 0;
156 }
157 
158 /**
159  * disable_ercr_checking - disables PCIe ECRC checking for a device
160  * @dev: the PCI device
161  *
162  * Returns 0 on success, or negative on failure.
163  */
164 static int disable_ecrc_checking(struct pci_dev *dev)
165 {
166 	int pos;
167 	u32 reg32;
168 
169 	if (!pci_is_pcie(dev))
170 		return -ENODEV;
171 
172 	pos = dev->aer_cap;
173 	if (!pos)
174 		return -ENODEV;
175 
176 	pci_read_config_dword(dev, pos + PCI_ERR_CAP, &reg32);
177 	reg32 &= ~(PCI_ERR_CAP_ECRC_GENE | PCI_ERR_CAP_ECRC_CHKE);
178 	pci_write_config_dword(dev, pos + PCI_ERR_CAP, reg32);
179 
180 	return 0;
181 }
182 
183 /**
184  * pcie_set_ecrc_checking - set/unset PCIe ECRC checking for a device based on global policy
185  * @dev: the PCI device
186  */
187 void pcie_set_ecrc_checking(struct pci_dev *dev)
188 {
189 	switch (ecrc_policy) {
190 	case ECRC_POLICY_DEFAULT:
191 		return;
192 	case ECRC_POLICY_OFF:
193 		disable_ecrc_checking(dev);
194 		break;
195 	case ECRC_POLICY_ON:
196 		enable_ecrc_checking(dev);
197 		break;
198 	default:
199 		return;
200 	}
201 }
202 
203 /**
204  * pcie_ecrc_get_policy - parse kernel command-line ecrc option
205  * @str: ECRC policy from kernel command line to use
206  */
207 void pcie_ecrc_get_policy(char *str)
208 {
209 	int i;
210 
211 	i = match_string(ecrc_policy_str, ARRAY_SIZE(ecrc_policy_str), str);
212 	if (i < 0)
213 		return;
214 
215 	ecrc_policy = i;
216 }
217 #endif	/* CONFIG_PCIE_ECRC */
218 
219 #ifdef CONFIG_ACPI_APEI
220 static inline int hest_match_pci(struct acpi_hest_aer_common *p,
221 				 struct pci_dev *pci)
222 {
223 	return   ACPI_HEST_SEGMENT(p->bus) == pci_domain_nr(pci->bus) &&
224 		 ACPI_HEST_BUS(p->bus)     == pci->bus->number &&
225 		 p->device                 == PCI_SLOT(pci->devfn) &&
226 		 p->function               == PCI_FUNC(pci->devfn);
227 }
228 
229 static inline bool hest_match_type(struct acpi_hest_header *hest_hdr,
230 				struct pci_dev *dev)
231 {
232 	u16 hest_type = hest_hdr->type;
233 	u8 pcie_type = pci_pcie_type(dev);
234 
235 	if ((hest_type == ACPI_HEST_TYPE_AER_ROOT_PORT &&
236 		pcie_type == PCI_EXP_TYPE_ROOT_PORT) ||
237 	    (hest_type == ACPI_HEST_TYPE_AER_ENDPOINT &&
238 		pcie_type == PCI_EXP_TYPE_ENDPOINT) ||
239 	    (hest_type == ACPI_HEST_TYPE_AER_BRIDGE &&
240 		(dev->class >> 16) == PCI_BASE_CLASS_BRIDGE))
241 		return true;
242 	return false;
243 }
244 
245 struct aer_hest_parse_info {
246 	struct pci_dev *pci_dev;
247 	int firmware_first;
248 };
249 
250 static int hest_source_is_pcie_aer(struct acpi_hest_header *hest_hdr)
251 {
252 	if (hest_hdr->type == ACPI_HEST_TYPE_AER_ROOT_PORT ||
253 	    hest_hdr->type == ACPI_HEST_TYPE_AER_ENDPOINT ||
254 	    hest_hdr->type == ACPI_HEST_TYPE_AER_BRIDGE)
255 		return 1;
256 	return 0;
257 }
258 
259 static int aer_hest_parse(struct acpi_hest_header *hest_hdr, void *data)
260 {
261 	struct aer_hest_parse_info *info = data;
262 	struct acpi_hest_aer_common *p;
263 	int ff;
264 
265 	if (!hest_source_is_pcie_aer(hest_hdr))
266 		return 0;
267 
268 	p = (struct acpi_hest_aer_common *)(hest_hdr + 1);
269 	ff = !!(p->flags & ACPI_HEST_FIRMWARE_FIRST);
270 
271 	/*
272 	 * If no specific device is supplied, determine whether
273 	 * FIRMWARE_FIRST is set for *any* PCIe device.
274 	 */
275 	if (!info->pci_dev) {
276 		info->firmware_first |= ff;
277 		return 0;
278 	}
279 
280 	/* Otherwise, check the specific device */
281 	if (p->flags & ACPI_HEST_GLOBAL) {
282 		if (hest_match_type(hest_hdr, info->pci_dev))
283 			info->firmware_first = ff;
284 	} else
285 		if (hest_match_pci(p, info->pci_dev))
286 			info->firmware_first = ff;
287 
288 	return 0;
289 }
290 
291 static void aer_set_firmware_first(struct pci_dev *pci_dev)
292 {
293 	int rc;
294 	struct aer_hest_parse_info info = {
295 		.pci_dev	= pci_dev,
296 		.firmware_first	= 0,
297 	};
298 
299 	rc = apei_hest_parse(aer_hest_parse, &info);
300 
301 	if (rc)
302 		pci_dev->__aer_firmware_first = 0;
303 	else
304 		pci_dev->__aer_firmware_first = info.firmware_first;
305 	pci_dev->__aer_firmware_first_valid = 1;
306 }
307 
308 int pcie_aer_get_firmware_first(struct pci_dev *dev)
309 {
310 	if (!pci_is_pcie(dev))
311 		return 0;
312 
313 	if (pcie_ports_native)
314 		return 0;
315 
316 	if (!dev->__aer_firmware_first_valid)
317 		aer_set_firmware_first(dev);
318 	return dev->__aer_firmware_first;
319 }
320 
321 static bool aer_firmware_first;
322 
323 /**
324  * aer_acpi_firmware_first - Check if APEI should control AER.
325  */
326 bool aer_acpi_firmware_first(void)
327 {
328 	static bool parsed = false;
329 	struct aer_hest_parse_info info = {
330 		.pci_dev	= NULL,	/* Check all PCIe devices */
331 		.firmware_first	= 0,
332 	};
333 
334 	if (pcie_ports_native)
335 		return false;
336 
337 	if (!parsed) {
338 		apei_hest_parse(aer_hest_parse, &info);
339 		aer_firmware_first = info.firmware_first;
340 		parsed = true;
341 	}
342 	return aer_firmware_first;
343 }
344 #endif
345 
346 #define	PCI_EXP_AER_FLAGS	(PCI_EXP_DEVCTL_CERE | PCI_EXP_DEVCTL_NFERE | \
347 				 PCI_EXP_DEVCTL_FERE | PCI_EXP_DEVCTL_URRE)
348 
349 int pci_enable_pcie_error_reporting(struct pci_dev *dev)
350 {
351 	if (pcie_aer_get_firmware_first(dev))
352 		return -EIO;
353 
354 	if (!dev->aer_cap)
355 		return -EIO;
356 
357 	return pcie_capability_set_word(dev, PCI_EXP_DEVCTL, PCI_EXP_AER_FLAGS);
358 }
359 EXPORT_SYMBOL_GPL(pci_enable_pcie_error_reporting);
360 
361 int pci_disable_pcie_error_reporting(struct pci_dev *dev)
362 {
363 	if (pcie_aer_get_firmware_first(dev))
364 		return -EIO;
365 
366 	return pcie_capability_clear_word(dev, PCI_EXP_DEVCTL,
367 					  PCI_EXP_AER_FLAGS);
368 }
369 EXPORT_SYMBOL_GPL(pci_disable_pcie_error_reporting);
370 
371 void pci_aer_clear_device_status(struct pci_dev *dev)
372 {
373 	u16 sta;
374 
375 	pcie_capability_read_word(dev, PCI_EXP_DEVSTA, &sta);
376 	pcie_capability_write_word(dev, PCI_EXP_DEVSTA, sta);
377 }
378 
379 int pci_cleanup_aer_uncorrect_error_status(struct pci_dev *dev)
380 {
381 	int pos;
382 	u32 status, sev;
383 
384 	pos = dev->aer_cap;
385 	if (!pos)
386 		return -EIO;
387 
388 	if (pcie_aer_get_firmware_first(dev))
389 		return -EIO;
390 
391 	/* Clear status bits for ERR_NONFATAL errors only */
392 	pci_read_config_dword(dev, pos + PCI_ERR_UNCOR_STATUS, &status);
393 	pci_read_config_dword(dev, pos + PCI_ERR_UNCOR_SEVER, &sev);
394 	status &= ~sev;
395 	if (status)
396 		pci_write_config_dword(dev, pos + PCI_ERR_UNCOR_STATUS, status);
397 
398 	return 0;
399 }
400 EXPORT_SYMBOL_GPL(pci_cleanup_aer_uncorrect_error_status);
401 
402 void pci_aer_clear_fatal_status(struct pci_dev *dev)
403 {
404 	int pos;
405 	u32 status, sev;
406 
407 	pos = dev->aer_cap;
408 	if (!pos)
409 		return;
410 
411 	if (pcie_aer_get_firmware_first(dev))
412 		return;
413 
414 	/* Clear status bits for ERR_FATAL errors only */
415 	pci_read_config_dword(dev, pos + PCI_ERR_UNCOR_STATUS, &status);
416 	pci_read_config_dword(dev, pos + PCI_ERR_UNCOR_SEVER, &sev);
417 	status &= sev;
418 	if (status)
419 		pci_write_config_dword(dev, pos + PCI_ERR_UNCOR_STATUS, status);
420 }
421 
422 int pci_cleanup_aer_error_status_regs(struct pci_dev *dev)
423 {
424 	int pos;
425 	u32 status;
426 	int port_type;
427 
428 	if (!pci_is_pcie(dev))
429 		return -ENODEV;
430 
431 	pos = dev->aer_cap;
432 	if (!pos)
433 		return -EIO;
434 
435 	if (pcie_aer_get_firmware_first(dev))
436 		return -EIO;
437 
438 	port_type = pci_pcie_type(dev);
439 	if (port_type == PCI_EXP_TYPE_ROOT_PORT) {
440 		pci_read_config_dword(dev, pos + PCI_ERR_ROOT_STATUS, &status);
441 		pci_write_config_dword(dev, pos + PCI_ERR_ROOT_STATUS, status);
442 	}
443 
444 	pci_read_config_dword(dev, pos + PCI_ERR_COR_STATUS, &status);
445 	pci_write_config_dword(dev, pos + PCI_ERR_COR_STATUS, status);
446 
447 	pci_read_config_dword(dev, pos + PCI_ERR_UNCOR_STATUS, &status);
448 	pci_write_config_dword(dev, pos + PCI_ERR_UNCOR_STATUS, status);
449 
450 	return 0;
451 }
452 
453 void pci_save_aer_state(struct pci_dev *dev)
454 {
455 	struct pci_cap_saved_state *save_state;
456 	u32 *cap;
457 	int pos;
458 
459 	pos = dev->aer_cap;
460 	if (!pos)
461 		return;
462 
463 	save_state = pci_find_saved_ext_cap(dev, PCI_EXT_CAP_ID_ERR);
464 	if (!save_state)
465 		return;
466 
467 	cap = &save_state->cap.data[0];
468 	pci_read_config_dword(dev, pos + PCI_ERR_UNCOR_MASK, cap++);
469 	pci_read_config_dword(dev, pos + PCI_ERR_UNCOR_SEVER, cap++);
470 	pci_read_config_dword(dev, pos + PCI_ERR_COR_MASK, cap++);
471 	pci_read_config_dword(dev, pos + PCI_ERR_CAP, cap++);
472 	if (pcie_cap_has_rtctl(dev))
473 		pci_read_config_dword(dev, pos + PCI_ERR_ROOT_COMMAND, cap++);
474 }
475 
476 void pci_restore_aer_state(struct pci_dev *dev)
477 {
478 	struct pci_cap_saved_state *save_state;
479 	u32 *cap;
480 	int pos;
481 
482 	pos = dev->aer_cap;
483 	if (!pos)
484 		return;
485 
486 	save_state = pci_find_saved_ext_cap(dev, PCI_EXT_CAP_ID_ERR);
487 	if (!save_state)
488 		return;
489 
490 	cap = &save_state->cap.data[0];
491 	pci_write_config_dword(dev, pos + PCI_ERR_UNCOR_MASK, *cap++);
492 	pci_write_config_dword(dev, pos + PCI_ERR_UNCOR_SEVER, *cap++);
493 	pci_write_config_dword(dev, pos + PCI_ERR_COR_MASK, *cap++);
494 	pci_write_config_dword(dev, pos + PCI_ERR_CAP, *cap++);
495 	if (pcie_cap_has_rtctl(dev))
496 		pci_write_config_dword(dev, pos + PCI_ERR_ROOT_COMMAND, *cap++);
497 }
498 
499 void pci_aer_init(struct pci_dev *dev)
500 {
501 	int n;
502 
503 	dev->aer_cap = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ERR);
504 	if (!dev->aer_cap)
505 		return;
506 
507 	dev->aer_stats = kzalloc(sizeof(struct aer_stats), GFP_KERNEL);
508 
509 	/*
510 	 * We save/restore PCI_ERR_UNCOR_MASK, PCI_ERR_UNCOR_SEVER,
511 	 * PCI_ERR_COR_MASK, and PCI_ERR_CAP.  Root and Root Complex Event
512 	 * Collectors also implement PCI_ERR_ROOT_COMMAND (PCIe r5.0, sec
513 	 * 7.8.4).
514 	 */
515 	n = pcie_cap_has_rtctl(dev) ? 5 : 4;
516 	pci_add_ext_cap_save_buffer(dev, PCI_EXT_CAP_ID_ERR, sizeof(u32) * n);
517 
518 	pci_cleanup_aer_error_status_regs(dev);
519 }
520 
521 void pci_aer_exit(struct pci_dev *dev)
522 {
523 	kfree(dev->aer_stats);
524 	dev->aer_stats = NULL;
525 }
526 
527 #define AER_AGENT_RECEIVER		0
528 #define AER_AGENT_REQUESTER		1
529 #define AER_AGENT_COMPLETER		2
530 #define AER_AGENT_TRANSMITTER		3
531 
532 #define AER_AGENT_REQUESTER_MASK(t)	((t == AER_CORRECTABLE) ?	\
533 	0 : (PCI_ERR_UNC_COMP_TIME|PCI_ERR_UNC_UNSUP))
534 #define AER_AGENT_COMPLETER_MASK(t)	((t == AER_CORRECTABLE) ?	\
535 	0 : PCI_ERR_UNC_COMP_ABORT)
536 #define AER_AGENT_TRANSMITTER_MASK(t)	((t == AER_CORRECTABLE) ?	\
537 	(PCI_ERR_COR_REP_ROLL|PCI_ERR_COR_REP_TIMER) : 0)
538 
539 #define AER_GET_AGENT(t, e)						\
540 	((e & AER_AGENT_COMPLETER_MASK(t)) ? AER_AGENT_COMPLETER :	\
541 	(e & AER_AGENT_REQUESTER_MASK(t)) ? AER_AGENT_REQUESTER :	\
542 	(e & AER_AGENT_TRANSMITTER_MASK(t)) ? AER_AGENT_TRANSMITTER :	\
543 	AER_AGENT_RECEIVER)
544 
545 #define AER_PHYSICAL_LAYER_ERROR	0
546 #define AER_DATA_LINK_LAYER_ERROR	1
547 #define AER_TRANSACTION_LAYER_ERROR	2
548 
549 #define AER_PHYSICAL_LAYER_ERROR_MASK(t) ((t == AER_CORRECTABLE) ?	\
550 	PCI_ERR_COR_RCVR : 0)
551 #define AER_DATA_LINK_LAYER_ERROR_MASK(t) ((t == AER_CORRECTABLE) ?	\
552 	(PCI_ERR_COR_BAD_TLP|						\
553 	PCI_ERR_COR_BAD_DLLP|						\
554 	PCI_ERR_COR_REP_ROLL|						\
555 	PCI_ERR_COR_REP_TIMER) : PCI_ERR_UNC_DLP)
556 
557 #define AER_GET_LAYER_ERROR(t, e)					\
558 	((e & AER_PHYSICAL_LAYER_ERROR_MASK(t)) ? AER_PHYSICAL_LAYER_ERROR : \
559 	(e & AER_DATA_LINK_LAYER_ERROR_MASK(t)) ? AER_DATA_LINK_LAYER_ERROR : \
560 	AER_TRANSACTION_LAYER_ERROR)
561 
562 /*
563  * AER error strings
564  */
565 static const char *aer_error_severity_string[] = {
566 	"Uncorrected (Non-Fatal)",
567 	"Uncorrected (Fatal)",
568 	"Corrected"
569 };
570 
571 static const char *aer_error_layer[] = {
572 	"Physical Layer",
573 	"Data Link Layer",
574 	"Transaction Layer"
575 };
576 
577 static const char *aer_correctable_error_string[AER_MAX_TYPEOF_COR_ERRS] = {
578 	"RxErr",			/* Bit Position 0	*/
579 	NULL,
580 	NULL,
581 	NULL,
582 	NULL,
583 	NULL,
584 	"BadTLP",			/* Bit Position 6	*/
585 	"BadDLLP",			/* Bit Position 7	*/
586 	"Rollover",			/* Bit Position 8	*/
587 	NULL,
588 	NULL,
589 	NULL,
590 	"Timeout",			/* Bit Position 12	*/
591 	"NonFatalErr",			/* Bit Position 13	*/
592 	"CorrIntErr",			/* Bit Position 14	*/
593 	"HeaderOF",			/* Bit Position 15	*/
594 };
595 
596 static const char *aer_uncorrectable_error_string[AER_MAX_TYPEOF_UNCOR_ERRS] = {
597 	"Undefined",			/* Bit Position 0	*/
598 	NULL,
599 	NULL,
600 	NULL,
601 	"DLP",				/* Bit Position 4	*/
602 	"SDES",				/* Bit Position 5	*/
603 	NULL,
604 	NULL,
605 	NULL,
606 	NULL,
607 	NULL,
608 	NULL,
609 	"TLP",				/* Bit Position 12	*/
610 	"FCP",				/* Bit Position 13	*/
611 	"CmpltTO",			/* Bit Position 14	*/
612 	"CmpltAbrt",			/* Bit Position 15	*/
613 	"UnxCmplt",			/* Bit Position 16	*/
614 	"RxOF",				/* Bit Position 17	*/
615 	"MalfTLP",			/* Bit Position 18	*/
616 	"ECRC",				/* Bit Position 19	*/
617 	"UnsupReq",			/* Bit Position 20	*/
618 	"ACSViol",			/* Bit Position 21	*/
619 	"UncorrIntErr",			/* Bit Position 22	*/
620 	"BlockedTLP",			/* Bit Position 23	*/
621 	"AtomicOpBlocked",		/* Bit Position 24	*/
622 	"TLPBlockedErr",		/* Bit Position 25	*/
623 	"PoisonTLPBlocked",		/* Bit Position 26	*/
624 };
625 
626 static const char *aer_agent_string[] = {
627 	"Receiver ID",
628 	"Requester ID",
629 	"Completer ID",
630 	"Transmitter ID"
631 };
632 
633 #define aer_stats_dev_attr(name, stats_array, strings_array,		\
634 			   total_string, total_field)			\
635 	static ssize_t							\
636 	name##_show(struct device *dev, struct device_attribute *attr,	\
637 		     char *buf)						\
638 {									\
639 	unsigned int i;							\
640 	char *str = buf;						\
641 	struct pci_dev *pdev = to_pci_dev(dev);				\
642 	u64 *stats = pdev->aer_stats->stats_array;			\
643 									\
644 	for (i = 0; i < ARRAY_SIZE(strings_array); i++) {		\
645 		if (strings_array[i])					\
646 			str += sprintf(str, "%s %llu\n",		\
647 				       strings_array[i], stats[i]);	\
648 		else if (stats[i])					\
649 			str += sprintf(str, #stats_array "_bit[%d] %llu\n",\
650 				       i, stats[i]);			\
651 	}								\
652 	str += sprintf(str, "TOTAL_%s %llu\n", total_string,		\
653 		       pdev->aer_stats->total_field);			\
654 	return str-buf;							\
655 }									\
656 static DEVICE_ATTR_RO(name)
657 
658 aer_stats_dev_attr(aer_dev_correctable, dev_cor_errs,
659 		   aer_correctable_error_string, "ERR_COR",
660 		   dev_total_cor_errs);
661 aer_stats_dev_attr(aer_dev_fatal, dev_fatal_errs,
662 		   aer_uncorrectable_error_string, "ERR_FATAL",
663 		   dev_total_fatal_errs);
664 aer_stats_dev_attr(aer_dev_nonfatal, dev_nonfatal_errs,
665 		   aer_uncorrectable_error_string, "ERR_NONFATAL",
666 		   dev_total_nonfatal_errs);
667 
668 #define aer_stats_rootport_attr(name, field)				\
669 	static ssize_t							\
670 	name##_show(struct device *dev, struct device_attribute *attr,	\
671 		     char *buf)						\
672 {									\
673 	struct pci_dev *pdev = to_pci_dev(dev);				\
674 	return sprintf(buf, "%llu\n", pdev->aer_stats->field);		\
675 }									\
676 static DEVICE_ATTR_RO(name)
677 
678 aer_stats_rootport_attr(aer_rootport_total_err_cor,
679 			 rootport_total_cor_errs);
680 aer_stats_rootport_attr(aer_rootport_total_err_fatal,
681 			 rootport_total_fatal_errs);
682 aer_stats_rootport_attr(aer_rootport_total_err_nonfatal,
683 			 rootport_total_nonfatal_errs);
684 
685 static struct attribute *aer_stats_attrs[] __ro_after_init = {
686 	&dev_attr_aer_dev_correctable.attr,
687 	&dev_attr_aer_dev_fatal.attr,
688 	&dev_attr_aer_dev_nonfatal.attr,
689 	&dev_attr_aer_rootport_total_err_cor.attr,
690 	&dev_attr_aer_rootport_total_err_fatal.attr,
691 	&dev_attr_aer_rootport_total_err_nonfatal.attr,
692 	NULL
693 };
694 
695 static umode_t aer_stats_attrs_are_visible(struct kobject *kobj,
696 					   struct attribute *a, int n)
697 {
698 	struct device *dev = kobj_to_dev(kobj);
699 	struct pci_dev *pdev = to_pci_dev(dev);
700 
701 	if (!pdev->aer_stats)
702 		return 0;
703 
704 	if ((a == &dev_attr_aer_rootport_total_err_cor.attr ||
705 	     a == &dev_attr_aer_rootport_total_err_fatal.attr ||
706 	     a == &dev_attr_aer_rootport_total_err_nonfatal.attr) &&
707 	    pci_pcie_type(pdev) != PCI_EXP_TYPE_ROOT_PORT)
708 		return 0;
709 
710 	return a->mode;
711 }
712 
713 const struct attribute_group aer_stats_attr_group = {
714 	.attrs  = aer_stats_attrs,
715 	.is_visible = aer_stats_attrs_are_visible,
716 };
717 
718 static void pci_dev_aer_stats_incr(struct pci_dev *pdev,
719 				   struct aer_err_info *info)
720 {
721 	unsigned long status = info->status & ~info->mask;
722 	int i, max = -1;
723 	u64 *counter = NULL;
724 	struct aer_stats *aer_stats = pdev->aer_stats;
725 
726 	if (!aer_stats)
727 		return;
728 
729 	switch (info->severity) {
730 	case AER_CORRECTABLE:
731 		aer_stats->dev_total_cor_errs++;
732 		counter = &aer_stats->dev_cor_errs[0];
733 		max = AER_MAX_TYPEOF_COR_ERRS;
734 		break;
735 	case AER_NONFATAL:
736 		aer_stats->dev_total_nonfatal_errs++;
737 		counter = &aer_stats->dev_nonfatal_errs[0];
738 		max = AER_MAX_TYPEOF_UNCOR_ERRS;
739 		break;
740 	case AER_FATAL:
741 		aer_stats->dev_total_fatal_errs++;
742 		counter = &aer_stats->dev_fatal_errs[0];
743 		max = AER_MAX_TYPEOF_UNCOR_ERRS;
744 		break;
745 	}
746 
747 	for_each_set_bit(i, &status, max)
748 		counter[i]++;
749 }
750 
751 static void pci_rootport_aer_stats_incr(struct pci_dev *pdev,
752 				 struct aer_err_source *e_src)
753 {
754 	struct aer_stats *aer_stats = pdev->aer_stats;
755 
756 	if (!aer_stats)
757 		return;
758 
759 	if (e_src->status & PCI_ERR_ROOT_COR_RCV)
760 		aer_stats->rootport_total_cor_errs++;
761 
762 	if (e_src->status & PCI_ERR_ROOT_UNCOR_RCV) {
763 		if (e_src->status & PCI_ERR_ROOT_FATAL_RCV)
764 			aer_stats->rootport_total_fatal_errs++;
765 		else
766 			aer_stats->rootport_total_nonfatal_errs++;
767 	}
768 }
769 
770 static void __print_tlp_header(struct pci_dev *dev,
771 			       struct aer_header_log_regs *t)
772 {
773 	pci_err(dev, "  TLP Header: %08x %08x %08x %08x\n",
774 		t->dw0, t->dw1, t->dw2, t->dw3);
775 }
776 
777 static void __aer_print_error(struct pci_dev *dev,
778 			      struct aer_err_info *info)
779 {
780 	unsigned long status = info->status & ~info->mask;
781 	const char *errmsg = NULL;
782 	int i;
783 
784 	for_each_set_bit(i, &status, 32) {
785 		if (info->severity == AER_CORRECTABLE)
786 			errmsg = i < ARRAY_SIZE(aer_correctable_error_string) ?
787 				aer_correctable_error_string[i] : NULL;
788 		else
789 			errmsg = i < ARRAY_SIZE(aer_uncorrectable_error_string) ?
790 				aer_uncorrectable_error_string[i] : NULL;
791 
792 		if (errmsg)
793 			pci_err(dev, "   [%2d] %-22s%s\n", i, errmsg,
794 				info->first_error == i ? " (First)" : "");
795 		else
796 			pci_err(dev, "   [%2d] Unknown Error Bit%s\n",
797 				i, info->first_error == i ? " (First)" : "");
798 	}
799 	pci_dev_aer_stats_incr(dev, info);
800 }
801 
802 void aer_print_error(struct pci_dev *dev, struct aer_err_info *info)
803 {
804 	int layer, agent;
805 	int id = ((dev->bus->number << 8) | dev->devfn);
806 
807 	if (!info->status) {
808 		pci_err(dev, "PCIe Bus Error: severity=%s, type=Inaccessible, (Unregistered Agent ID)\n",
809 			aer_error_severity_string[info->severity]);
810 		goto out;
811 	}
812 
813 	layer = AER_GET_LAYER_ERROR(info->severity, info->status);
814 	agent = AER_GET_AGENT(info->severity, info->status);
815 
816 	pci_err(dev, "PCIe Bus Error: severity=%s, type=%s, (%s)\n",
817 		aer_error_severity_string[info->severity],
818 		aer_error_layer[layer], aer_agent_string[agent]);
819 
820 	pci_err(dev, "  device [%04x:%04x] error status/mask=%08x/%08x\n",
821 		dev->vendor, dev->device,
822 		info->status, info->mask);
823 
824 	__aer_print_error(dev, info);
825 
826 	if (info->tlp_header_valid)
827 		__print_tlp_header(dev, &info->tlp);
828 
829 out:
830 	if (info->id && info->error_dev_num > 1 && info->id == id)
831 		pci_err(dev, "  Error of this Agent is reported first\n");
832 
833 	trace_aer_event(dev_name(&dev->dev), (info->status & ~info->mask),
834 			info->severity, info->tlp_header_valid, &info->tlp);
835 }
836 
837 static void aer_print_port_info(struct pci_dev *dev, struct aer_err_info *info)
838 {
839 	u8 bus = info->id >> 8;
840 	u8 devfn = info->id & 0xff;
841 
842 	pci_info(dev, "%s%s error received: %04x:%02x:%02x.%d\n",
843 		 info->multi_error_valid ? "Multiple " : "",
844 		 aer_error_severity_string[info->severity],
845 		 pci_domain_nr(dev->bus), bus, PCI_SLOT(devfn),
846 		 PCI_FUNC(devfn));
847 }
848 
849 #ifdef CONFIG_ACPI_APEI_PCIEAER
850 int cper_severity_to_aer(int cper_severity)
851 {
852 	switch (cper_severity) {
853 	case CPER_SEV_RECOVERABLE:
854 		return AER_NONFATAL;
855 	case CPER_SEV_FATAL:
856 		return AER_FATAL;
857 	default:
858 		return AER_CORRECTABLE;
859 	}
860 }
861 EXPORT_SYMBOL_GPL(cper_severity_to_aer);
862 
863 void cper_print_aer(struct pci_dev *dev, int aer_severity,
864 		    struct aer_capability_regs *aer)
865 {
866 	int layer, agent, tlp_header_valid = 0;
867 	u32 status, mask;
868 	struct aer_err_info info;
869 
870 	if (aer_severity == AER_CORRECTABLE) {
871 		status = aer->cor_status;
872 		mask = aer->cor_mask;
873 	} else {
874 		status = aer->uncor_status;
875 		mask = aer->uncor_mask;
876 		tlp_header_valid = status & AER_LOG_TLP_MASKS;
877 	}
878 
879 	layer = AER_GET_LAYER_ERROR(aer_severity, status);
880 	agent = AER_GET_AGENT(aer_severity, status);
881 
882 	memset(&info, 0, sizeof(info));
883 	info.severity = aer_severity;
884 	info.status = status;
885 	info.mask = mask;
886 	info.first_error = PCI_ERR_CAP_FEP(aer->cap_control);
887 
888 	pci_err(dev, "aer_status: 0x%08x, aer_mask: 0x%08x\n", status, mask);
889 	__aer_print_error(dev, &info);
890 	pci_err(dev, "aer_layer=%s, aer_agent=%s\n",
891 		aer_error_layer[layer], aer_agent_string[agent]);
892 
893 	if (aer_severity != AER_CORRECTABLE)
894 		pci_err(dev, "aer_uncor_severity: 0x%08x\n",
895 			aer->uncor_severity);
896 
897 	if (tlp_header_valid)
898 		__print_tlp_header(dev, &aer->header_log);
899 
900 	trace_aer_event(dev_name(&dev->dev), (status & ~mask),
901 			aer_severity, tlp_header_valid, &aer->header_log);
902 }
903 #endif
904 
905 /**
906  * add_error_device - list device to be handled
907  * @e_info: pointer to error info
908  * @dev: pointer to pci_dev to be added
909  */
910 static int add_error_device(struct aer_err_info *e_info, struct pci_dev *dev)
911 {
912 	if (e_info->error_dev_num < AER_MAX_MULTI_ERR_DEVICES) {
913 		e_info->dev[e_info->error_dev_num] = pci_dev_get(dev);
914 		e_info->error_dev_num++;
915 		return 0;
916 	}
917 	return -ENOSPC;
918 }
919 
920 /**
921  * is_error_source - check whether the device is source of reported error
922  * @dev: pointer to pci_dev to be checked
923  * @e_info: pointer to reported error info
924  */
925 static bool is_error_source(struct pci_dev *dev, struct aer_err_info *e_info)
926 {
927 	int pos;
928 	u32 status, mask;
929 	u16 reg16;
930 
931 	/*
932 	 * When bus id is equal to 0, it might be a bad id
933 	 * reported by root port.
934 	 */
935 	if ((PCI_BUS_NUM(e_info->id) != 0) &&
936 	    !(dev->bus->bus_flags & PCI_BUS_FLAGS_NO_AERSID)) {
937 		/* Device ID match? */
938 		if (e_info->id == ((dev->bus->number << 8) | dev->devfn))
939 			return true;
940 
941 		/* Continue id comparing if there is no multiple error */
942 		if (!e_info->multi_error_valid)
943 			return false;
944 	}
945 
946 	/*
947 	 * When either
948 	 *      1) bus id is equal to 0. Some ports might lose the bus
949 	 *              id of error source id;
950 	 *      2) bus flag PCI_BUS_FLAGS_NO_AERSID is set
951 	 *      3) There are multiple errors and prior ID comparing fails;
952 	 * We check AER status registers to find possible reporter.
953 	 */
954 	if (atomic_read(&dev->enable_cnt) == 0)
955 		return false;
956 
957 	/* Check if AER is enabled */
958 	pcie_capability_read_word(dev, PCI_EXP_DEVCTL, &reg16);
959 	if (!(reg16 & PCI_EXP_AER_FLAGS))
960 		return false;
961 
962 	pos = dev->aer_cap;
963 	if (!pos)
964 		return false;
965 
966 	/* Check if error is recorded */
967 	if (e_info->severity == AER_CORRECTABLE) {
968 		pci_read_config_dword(dev, pos + PCI_ERR_COR_STATUS, &status);
969 		pci_read_config_dword(dev, pos + PCI_ERR_COR_MASK, &mask);
970 	} else {
971 		pci_read_config_dword(dev, pos + PCI_ERR_UNCOR_STATUS, &status);
972 		pci_read_config_dword(dev, pos + PCI_ERR_UNCOR_MASK, &mask);
973 	}
974 	if (status & ~mask)
975 		return true;
976 
977 	return false;
978 }
979 
980 static int find_device_iter(struct pci_dev *dev, void *data)
981 {
982 	struct aer_err_info *e_info = (struct aer_err_info *)data;
983 
984 	if (is_error_source(dev, e_info)) {
985 		/* List this device */
986 		if (add_error_device(e_info, dev)) {
987 			/* We cannot handle more... Stop iteration */
988 			/* TODO: Should print error message here? */
989 			return 1;
990 		}
991 
992 		/* If there is only a single error, stop iteration */
993 		if (!e_info->multi_error_valid)
994 			return 1;
995 	}
996 	return 0;
997 }
998 
999 /**
1000  * find_source_device - search through device hierarchy for source device
1001  * @parent: pointer to Root Port pci_dev data structure
1002  * @e_info: including detailed error information such like id
1003  *
1004  * Return true if found.
1005  *
1006  * Invoked by DPC when error is detected at the Root Port.
1007  * Caller of this function must set id, severity, and multi_error_valid of
1008  * struct aer_err_info pointed by @e_info properly.  This function must fill
1009  * e_info->error_dev_num and e_info->dev[], based on the given information.
1010  */
1011 static bool find_source_device(struct pci_dev *parent,
1012 		struct aer_err_info *e_info)
1013 {
1014 	struct pci_dev *dev = parent;
1015 	int result;
1016 
1017 	/* Must reset in this function */
1018 	e_info->error_dev_num = 0;
1019 
1020 	/* Is Root Port an agent that sends error message? */
1021 	result = find_device_iter(dev, e_info);
1022 	if (result)
1023 		return true;
1024 
1025 	pci_walk_bus(parent->subordinate, find_device_iter, e_info);
1026 
1027 	if (!e_info->error_dev_num) {
1028 		pci_info(parent, "can't find device of ID%04x\n", e_info->id);
1029 		return false;
1030 	}
1031 	return true;
1032 }
1033 
1034 /**
1035  * handle_error_source - handle logging error into an event log
1036  * @dev: pointer to pci_dev data structure of error source device
1037  * @info: comprehensive error information
1038  *
1039  * Invoked when an error being detected by Root Port.
1040  */
1041 static void handle_error_source(struct pci_dev *dev, struct aer_err_info *info)
1042 {
1043 	int pos;
1044 
1045 	if (info->severity == AER_CORRECTABLE) {
1046 		/*
1047 		 * Correctable error does not need software intervention.
1048 		 * No need to go through error recovery process.
1049 		 */
1050 		pos = dev->aer_cap;
1051 		if (pos)
1052 			pci_write_config_dword(dev, pos + PCI_ERR_COR_STATUS,
1053 					info->status);
1054 		pci_aer_clear_device_status(dev);
1055 	} else if (info->severity == AER_NONFATAL)
1056 		pcie_do_recovery(dev, pci_channel_io_normal,
1057 				 PCIE_PORT_SERVICE_AER);
1058 	else if (info->severity == AER_FATAL)
1059 		pcie_do_recovery(dev, pci_channel_io_frozen,
1060 				 PCIE_PORT_SERVICE_AER);
1061 	pci_dev_put(dev);
1062 }
1063 
1064 #ifdef CONFIG_ACPI_APEI_PCIEAER
1065 
1066 #define AER_RECOVER_RING_ORDER		4
1067 #define AER_RECOVER_RING_SIZE		(1 << AER_RECOVER_RING_ORDER)
1068 
1069 struct aer_recover_entry {
1070 	u8	bus;
1071 	u8	devfn;
1072 	u16	domain;
1073 	int	severity;
1074 	struct aer_capability_regs *regs;
1075 };
1076 
1077 static DEFINE_KFIFO(aer_recover_ring, struct aer_recover_entry,
1078 		    AER_RECOVER_RING_SIZE);
1079 
1080 static void aer_recover_work_func(struct work_struct *work)
1081 {
1082 	struct aer_recover_entry entry;
1083 	struct pci_dev *pdev;
1084 
1085 	while (kfifo_get(&aer_recover_ring, &entry)) {
1086 		pdev = pci_get_domain_bus_and_slot(entry.domain, entry.bus,
1087 						   entry.devfn);
1088 		if (!pdev) {
1089 			pr_err("AER recover: Can not find pci_dev for %04x:%02x:%02x:%x\n",
1090 			       entry.domain, entry.bus,
1091 			       PCI_SLOT(entry.devfn), PCI_FUNC(entry.devfn));
1092 			continue;
1093 		}
1094 		cper_print_aer(pdev, entry.severity, entry.regs);
1095 		if (entry.severity == AER_NONFATAL)
1096 			pcie_do_recovery(pdev, pci_channel_io_normal,
1097 					 PCIE_PORT_SERVICE_AER);
1098 		else if (entry.severity == AER_FATAL)
1099 			pcie_do_recovery(pdev, pci_channel_io_frozen,
1100 					 PCIE_PORT_SERVICE_AER);
1101 		pci_dev_put(pdev);
1102 	}
1103 }
1104 
1105 /*
1106  * Mutual exclusion for writers of aer_recover_ring, reader side don't
1107  * need lock, because there is only one reader and lock is not needed
1108  * between reader and writer.
1109  */
1110 static DEFINE_SPINLOCK(aer_recover_ring_lock);
1111 static DECLARE_WORK(aer_recover_work, aer_recover_work_func);
1112 
1113 void aer_recover_queue(int domain, unsigned int bus, unsigned int devfn,
1114 		       int severity, struct aer_capability_regs *aer_regs)
1115 {
1116 	struct aer_recover_entry entry = {
1117 		.bus		= bus,
1118 		.devfn		= devfn,
1119 		.domain		= domain,
1120 		.severity	= severity,
1121 		.regs		= aer_regs,
1122 	};
1123 
1124 	if (kfifo_in_spinlocked(&aer_recover_ring, &entry, 1,
1125 				 &aer_recover_ring_lock))
1126 		schedule_work(&aer_recover_work);
1127 	else
1128 		pr_err("AER recover: Buffer overflow when recovering AER for %04x:%02x:%02x:%x\n",
1129 		       domain, bus, PCI_SLOT(devfn), PCI_FUNC(devfn));
1130 }
1131 EXPORT_SYMBOL_GPL(aer_recover_queue);
1132 #endif
1133 
1134 /**
1135  * aer_get_device_error_info - read error status from dev and store it to info
1136  * @dev: pointer to the device expected to have a error record
1137  * @info: pointer to structure to store the error record
1138  *
1139  * Return 1 on success, 0 on error.
1140  *
1141  * Note that @info is reused among all error devices. Clear fields properly.
1142  */
1143 int aer_get_device_error_info(struct pci_dev *dev, struct aer_err_info *info)
1144 {
1145 	int pos, temp;
1146 
1147 	/* Must reset in this function */
1148 	info->status = 0;
1149 	info->tlp_header_valid = 0;
1150 
1151 	pos = dev->aer_cap;
1152 
1153 	/* The device might not support AER */
1154 	if (!pos)
1155 		return 0;
1156 
1157 	if (info->severity == AER_CORRECTABLE) {
1158 		pci_read_config_dword(dev, pos + PCI_ERR_COR_STATUS,
1159 			&info->status);
1160 		pci_read_config_dword(dev, pos + PCI_ERR_COR_MASK,
1161 			&info->mask);
1162 		if (!(info->status & ~info->mask))
1163 			return 0;
1164 	} else if (pci_pcie_type(dev) == PCI_EXP_TYPE_ROOT_PORT ||
1165 	           pci_pcie_type(dev) == PCI_EXP_TYPE_DOWNSTREAM ||
1166 		   info->severity == AER_NONFATAL) {
1167 
1168 		/* Link is still healthy for IO reads */
1169 		pci_read_config_dword(dev, pos + PCI_ERR_UNCOR_STATUS,
1170 			&info->status);
1171 		pci_read_config_dword(dev, pos + PCI_ERR_UNCOR_MASK,
1172 			&info->mask);
1173 		if (!(info->status & ~info->mask))
1174 			return 0;
1175 
1176 		/* Get First Error Pointer */
1177 		pci_read_config_dword(dev, pos + PCI_ERR_CAP, &temp);
1178 		info->first_error = PCI_ERR_CAP_FEP(temp);
1179 
1180 		if (info->status & AER_LOG_TLP_MASKS) {
1181 			info->tlp_header_valid = 1;
1182 			pci_read_config_dword(dev,
1183 				pos + PCI_ERR_HEADER_LOG, &info->tlp.dw0);
1184 			pci_read_config_dword(dev,
1185 				pos + PCI_ERR_HEADER_LOG + 4, &info->tlp.dw1);
1186 			pci_read_config_dword(dev,
1187 				pos + PCI_ERR_HEADER_LOG + 8, &info->tlp.dw2);
1188 			pci_read_config_dword(dev,
1189 				pos + PCI_ERR_HEADER_LOG + 12, &info->tlp.dw3);
1190 		}
1191 	}
1192 
1193 	return 1;
1194 }
1195 
1196 static inline void aer_process_err_devices(struct aer_err_info *e_info)
1197 {
1198 	int i;
1199 
1200 	/* Report all before handle them, not to lost records by reset etc. */
1201 	for (i = 0; i < e_info->error_dev_num && e_info->dev[i]; i++) {
1202 		if (aer_get_device_error_info(e_info->dev[i], e_info))
1203 			aer_print_error(e_info->dev[i], e_info);
1204 	}
1205 	for (i = 0; i < e_info->error_dev_num && e_info->dev[i]; i++) {
1206 		if (aer_get_device_error_info(e_info->dev[i], e_info))
1207 			handle_error_source(e_info->dev[i], e_info);
1208 	}
1209 }
1210 
1211 /**
1212  * aer_isr_one_error - consume an error detected by root port
1213  * @rpc: pointer to the root port which holds an error
1214  * @e_src: pointer to an error source
1215  */
1216 static void aer_isr_one_error(struct aer_rpc *rpc,
1217 		struct aer_err_source *e_src)
1218 {
1219 	struct pci_dev *pdev = rpc->rpd;
1220 	struct aer_err_info e_info;
1221 
1222 	pci_rootport_aer_stats_incr(pdev, e_src);
1223 
1224 	/*
1225 	 * There is a possibility that both correctable error and
1226 	 * uncorrectable error being logged. Report correctable error first.
1227 	 */
1228 	if (e_src->status & PCI_ERR_ROOT_COR_RCV) {
1229 		e_info.id = ERR_COR_ID(e_src->id);
1230 		e_info.severity = AER_CORRECTABLE;
1231 
1232 		if (e_src->status & PCI_ERR_ROOT_MULTI_COR_RCV)
1233 			e_info.multi_error_valid = 1;
1234 		else
1235 			e_info.multi_error_valid = 0;
1236 		aer_print_port_info(pdev, &e_info);
1237 
1238 		if (find_source_device(pdev, &e_info))
1239 			aer_process_err_devices(&e_info);
1240 	}
1241 
1242 	if (e_src->status & PCI_ERR_ROOT_UNCOR_RCV) {
1243 		e_info.id = ERR_UNCOR_ID(e_src->id);
1244 
1245 		if (e_src->status & PCI_ERR_ROOT_FATAL_RCV)
1246 			e_info.severity = AER_FATAL;
1247 		else
1248 			e_info.severity = AER_NONFATAL;
1249 
1250 		if (e_src->status & PCI_ERR_ROOT_MULTI_UNCOR_RCV)
1251 			e_info.multi_error_valid = 1;
1252 		else
1253 			e_info.multi_error_valid = 0;
1254 
1255 		aer_print_port_info(pdev, &e_info);
1256 
1257 		if (find_source_device(pdev, &e_info))
1258 			aer_process_err_devices(&e_info);
1259 	}
1260 }
1261 
1262 /**
1263  * aer_isr - consume errors detected by root port
1264  * @irq: IRQ assigned to Root Port
1265  * @context: pointer to Root Port data structure
1266  *
1267  * Invoked, as DPC, when root port records new detected error
1268  */
1269 static irqreturn_t aer_isr(int irq, void *context)
1270 {
1271 	struct pcie_device *dev = (struct pcie_device *)context;
1272 	struct aer_rpc *rpc = get_service_data(dev);
1273 	struct aer_err_source uninitialized_var(e_src);
1274 
1275 	if (kfifo_is_empty(&rpc->aer_fifo))
1276 		return IRQ_NONE;
1277 
1278 	while (kfifo_get(&rpc->aer_fifo, &e_src))
1279 		aer_isr_one_error(rpc, &e_src);
1280 	return IRQ_HANDLED;
1281 }
1282 
1283 /**
1284  * aer_irq - Root Port's ISR
1285  * @irq: IRQ assigned to Root Port
1286  * @context: pointer to Root Port data structure
1287  *
1288  * Invoked when Root Port detects AER messages.
1289  */
1290 static irqreturn_t aer_irq(int irq, void *context)
1291 {
1292 	struct pcie_device *pdev = (struct pcie_device *)context;
1293 	struct aer_rpc *rpc = get_service_data(pdev);
1294 	struct pci_dev *rp = rpc->rpd;
1295 	struct aer_err_source e_src = {};
1296 	int pos = rp->aer_cap;
1297 
1298 	pci_read_config_dword(rp, pos + PCI_ERR_ROOT_STATUS, &e_src.status);
1299 	if (!(e_src.status & (PCI_ERR_ROOT_UNCOR_RCV|PCI_ERR_ROOT_COR_RCV)))
1300 		return IRQ_NONE;
1301 
1302 	pci_read_config_dword(rp, pos + PCI_ERR_ROOT_ERR_SRC, &e_src.id);
1303 	pci_write_config_dword(rp, pos + PCI_ERR_ROOT_STATUS, e_src.status);
1304 
1305 	if (!kfifo_put(&rpc->aer_fifo, e_src))
1306 		return IRQ_HANDLED;
1307 
1308 	return IRQ_WAKE_THREAD;
1309 }
1310 
1311 static int set_device_error_reporting(struct pci_dev *dev, void *data)
1312 {
1313 	bool enable = *((bool *)data);
1314 	int type = pci_pcie_type(dev);
1315 
1316 	if ((type == PCI_EXP_TYPE_ROOT_PORT) ||
1317 	    (type == PCI_EXP_TYPE_UPSTREAM) ||
1318 	    (type == PCI_EXP_TYPE_DOWNSTREAM)) {
1319 		if (enable)
1320 			pci_enable_pcie_error_reporting(dev);
1321 		else
1322 			pci_disable_pcie_error_reporting(dev);
1323 	}
1324 
1325 	if (enable)
1326 		pcie_set_ecrc_checking(dev);
1327 
1328 	return 0;
1329 }
1330 
1331 /**
1332  * set_downstream_devices_error_reporting - enable/disable the error reporting  bits on the root port and its downstream ports.
1333  * @dev: pointer to root port's pci_dev data structure
1334  * @enable: true = enable error reporting, false = disable error reporting.
1335  */
1336 static void set_downstream_devices_error_reporting(struct pci_dev *dev,
1337 						   bool enable)
1338 {
1339 	set_device_error_reporting(dev, &enable);
1340 
1341 	if (!dev->subordinate)
1342 		return;
1343 	pci_walk_bus(dev->subordinate, set_device_error_reporting, &enable);
1344 }
1345 
1346 /**
1347  * aer_enable_rootport - enable Root Port's interrupts when receiving messages
1348  * @rpc: pointer to a Root Port data structure
1349  *
1350  * Invoked when PCIe bus loads AER service driver.
1351  */
1352 static void aer_enable_rootport(struct aer_rpc *rpc)
1353 {
1354 	struct pci_dev *pdev = rpc->rpd;
1355 	int aer_pos;
1356 	u16 reg16;
1357 	u32 reg32;
1358 
1359 	/* Clear PCIe Capability's Device Status */
1360 	pcie_capability_read_word(pdev, PCI_EXP_DEVSTA, &reg16);
1361 	pcie_capability_write_word(pdev, PCI_EXP_DEVSTA, reg16);
1362 
1363 	/* Disable system error generation in response to error messages */
1364 	pcie_capability_clear_word(pdev, PCI_EXP_RTCTL,
1365 				   SYSTEM_ERROR_INTR_ON_MESG_MASK);
1366 
1367 	aer_pos = pdev->aer_cap;
1368 	/* Clear error status */
1369 	pci_read_config_dword(pdev, aer_pos + PCI_ERR_ROOT_STATUS, &reg32);
1370 	pci_write_config_dword(pdev, aer_pos + PCI_ERR_ROOT_STATUS, reg32);
1371 	pci_read_config_dword(pdev, aer_pos + PCI_ERR_COR_STATUS, &reg32);
1372 	pci_write_config_dword(pdev, aer_pos + PCI_ERR_COR_STATUS, reg32);
1373 	pci_read_config_dword(pdev, aer_pos + PCI_ERR_UNCOR_STATUS, &reg32);
1374 	pci_write_config_dword(pdev, aer_pos + PCI_ERR_UNCOR_STATUS, reg32);
1375 
1376 	/*
1377 	 * Enable error reporting for the root port device and downstream port
1378 	 * devices.
1379 	 */
1380 	set_downstream_devices_error_reporting(pdev, true);
1381 
1382 	/* Enable Root Port's interrupt in response to error messages */
1383 	pci_read_config_dword(pdev, aer_pos + PCI_ERR_ROOT_COMMAND, &reg32);
1384 	reg32 |= ROOT_PORT_INTR_ON_MESG_MASK;
1385 	pci_write_config_dword(pdev, aer_pos + PCI_ERR_ROOT_COMMAND, reg32);
1386 }
1387 
1388 /**
1389  * aer_disable_rootport - disable Root Port's interrupts when receiving messages
1390  * @rpc: pointer to a Root Port data structure
1391  *
1392  * Invoked when PCIe bus unloads AER service driver.
1393  */
1394 static void aer_disable_rootport(struct aer_rpc *rpc)
1395 {
1396 	struct pci_dev *pdev = rpc->rpd;
1397 	u32 reg32;
1398 	int pos;
1399 
1400 	/*
1401 	 * Disable error reporting for the root port device and downstream port
1402 	 * devices.
1403 	 */
1404 	set_downstream_devices_error_reporting(pdev, false);
1405 
1406 	pos = pdev->aer_cap;
1407 	/* Disable Root's interrupt in response to error messages */
1408 	pci_read_config_dword(pdev, pos + PCI_ERR_ROOT_COMMAND, &reg32);
1409 	reg32 &= ~ROOT_PORT_INTR_ON_MESG_MASK;
1410 	pci_write_config_dword(pdev, pos + PCI_ERR_ROOT_COMMAND, reg32);
1411 
1412 	/* Clear Root's error status reg */
1413 	pci_read_config_dword(pdev, pos + PCI_ERR_ROOT_STATUS, &reg32);
1414 	pci_write_config_dword(pdev, pos + PCI_ERR_ROOT_STATUS, reg32);
1415 }
1416 
1417 /**
1418  * aer_remove - clean up resources
1419  * @dev: pointer to the pcie_dev data structure
1420  *
1421  * Invoked when PCI Express bus unloads or AER probe fails.
1422  */
1423 static void aer_remove(struct pcie_device *dev)
1424 {
1425 	struct aer_rpc *rpc = get_service_data(dev);
1426 
1427 	aer_disable_rootport(rpc);
1428 }
1429 
1430 /**
1431  * aer_probe - initialize resources
1432  * @dev: pointer to the pcie_dev data structure
1433  *
1434  * Invoked when PCI Express bus loads AER service driver.
1435  */
1436 static int aer_probe(struct pcie_device *dev)
1437 {
1438 	int status;
1439 	struct aer_rpc *rpc;
1440 	struct device *device = &dev->device;
1441 	struct pci_dev *port = dev->port;
1442 
1443 	rpc = devm_kzalloc(device, sizeof(struct aer_rpc), GFP_KERNEL);
1444 	if (!rpc)
1445 		return -ENOMEM;
1446 
1447 	rpc->rpd = port;
1448 	INIT_KFIFO(rpc->aer_fifo);
1449 	set_service_data(dev, rpc);
1450 
1451 	status = devm_request_threaded_irq(device, dev->irq, aer_irq, aer_isr,
1452 					   IRQF_SHARED, "aerdrv", dev);
1453 	if (status) {
1454 		pci_err(port, "request AER IRQ %d failed\n", dev->irq);
1455 		return status;
1456 	}
1457 
1458 	aer_enable_rootport(rpc);
1459 	pci_info(port, "enabled with IRQ %d\n", dev->irq);
1460 	return 0;
1461 }
1462 
1463 /**
1464  * aer_root_reset - reset link on Root Port
1465  * @dev: pointer to Root Port's pci_dev data structure
1466  *
1467  * Invoked by Port Bus driver when performing link reset at Root Port.
1468  */
1469 static pci_ers_result_t aer_root_reset(struct pci_dev *dev)
1470 {
1471 	u32 reg32;
1472 	int pos;
1473 	int rc;
1474 
1475 	pos = dev->aer_cap;
1476 
1477 	/* Disable Root's interrupt in response to error messages */
1478 	pci_read_config_dword(dev, pos + PCI_ERR_ROOT_COMMAND, &reg32);
1479 	reg32 &= ~ROOT_PORT_INTR_ON_MESG_MASK;
1480 	pci_write_config_dword(dev, pos + PCI_ERR_ROOT_COMMAND, reg32);
1481 
1482 	rc = pci_bus_error_reset(dev);
1483 	pci_info(dev, "Root Port link has been reset\n");
1484 
1485 	/* Clear Root Error Status */
1486 	pci_read_config_dword(dev, pos + PCI_ERR_ROOT_STATUS, &reg32);
1487 	pci_write_config_dword(dev, pos + PCI_ERR_ROOT_STATUS, reg32);
1488 
1489 	/* Enable Root Port's interrupt in response to error messages */
1490 	pci_read_config_dword(dev, pos + PCI_ERR_ROOT_COMMAND, &reg32);
1491 	reg32 |= ROOT_PORT_INTR_ON_MESG_MASK;
1492 	pci_write_config_dword(dev, pos + PCI_ERR_ROOT_COMMAND, reg32);
1493 
1494 	return rc ? PCI_ERS_RESULT_DISCONNECT : PCI_ERS_RESULT_RECOVERED;
1495 }
1496 
1497 static struct pcie_port_service_driver aerdriver = {
1498 	.name		= "aer",
1499 	.port_type	= PCI_EXP_TYPE_ROOT_PORT,
1500 	.service	= PCIE_PORT_SERVICE_AER,
1501 
1502 	.probe		= aer_probe,
1503 	.remove		= aer_remove,
1504 	.reset_link	= aer_root_reset,
1505 };
1506 
1507 /**
1508  * aer_service_init - register AER root service driver
1509  *
1510  * Invoked when AER root service driver is loaded.
1511  */
1512 int __init pcie_aer_init(void)
1513 {
1514 	if (!pci_aer_available() || aer_acpi_firmware_first())
1515 		return -ENXIO;
1516 	return pcie_port_service_register(&aerdriver);
1517 }
1518