xref: /linux/drivers/pci/pcie/aer.c (revision e812928be2ee1c2744adf20ed04e0ce1e2fc5c13)
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/dev_printk.h>
21 #include <linux/pci.h>
22 #include <linux/pci-acpi.h>
23 #include <linux/sched.h>
24 #include <linux/kernel.h>
25 #include <linux/errno.h>
26 #include <linux/pm.h>
27 #include <linux/init.h>
28 #include <linux/interrupt.h>
29 #include <linux/delay.h>
30 #include <linux/kfifo.h>
31 #include <linux/ratelimit.h>
32 #include <linux/slab.h>
33 #include <linux/vmcore_info.h>
34 #include <acpi/apei.h>
35 #include <acpi/ghes.h>
36 #include <ras/ras_event.h>
37 
38 #include "../pci.h"
39 #include "portdrv.h"
40 
41 #define aer_printk(level, pdev, fmt, arg...) \
42 	dev_printk(level, &(pdev)->dev, fmt, ##arg)
43 
44 #define AER_ERROR_SOURCES_MAX		128
45 
46 #define AER_MAX_TYPEOF_COR_ERRS		16	/* as per PCI_ERR_COR_STATUS */
47 #define AER_MAX_TYPEOF_UNCOR_ERRS	32	/* as per PCI_ERR_UNCOR_STATUS*/
48 
49 struct aer_err_source {
50 	u32 status;			/* PCI_ERR_ROOT_STATUS */
51 	u32 id;				/* PCI_ERR_ROOT_ERR_SRC */
52 };
53 
54 struct aer_rpc {
55 	struct pci_dev *rpd;		/* Root Port device */
56 	DECLARE_KFIFO(aer_fifo, struct aer_err_source, AER_ERROR_SOURCES_MAX);
57 };
58 
59 /* AER info for the device */
60 struct aer_info {
61 
62 	/*
63 	 * Fields for all AER capable devices. They indicate the errors
64 	 * "as seen by this device". Note that this may mean that if an
65 	 * Endpoint is causing problems, the AER counters may increment
66 	 * at its link partner (e.g. Root Port) because the errors will be
67 	 * "seen" by the link partner and not the problematic Endpoint
68 	 * itself (which may report all counters as 0 as it never saw any
69 	 * problems).
70 	 */
71 	/* Counters for different type of correctable errors */
72 	u64 dev_cor_errs[AER_MAX_TYPEOF_COR_ERRS];
73 	/* Counters for different type of fatal uncorrectable errors */
74 	u64 dev_fatal_errs[AER_MAX_TYPEOF_UNCOR_ERRS];
75 	/* Counters for different type of nonfatal uncorrectable errors */
76 	u64 dev_nonfatal_errs[AER_MAX_TYPEOF_UNCOR_ERRS];
77 	/* Total number of ERR_COR sent by this device */
78 	u64 dev_total_cor_errs;
79 	/* Total number of ERR_FATAL sent by this device */
80 	u64 dev_total_fatal_errs;
81 	/* Total number of ERR_NONFATAL sent by this device */
82 	u64 dev_total_nonfatal_errs;
83 
84 	/*
85 	 * Fields for Root Ports & Root Complex Event Collectors only; these
86 	 * indicate the total number of ERR_COR, ERR_FATAL, and ERR_NONFATAL
87 	 * messages received by the Root Port / Event Collector, INCLUDING the
88 	 * ones that are generated internally (by the Root Port itself)
89 	 */
90 	u64 rootport_total_cor_errs;
91 	u64 rootport_total_fatal_errs;
92 	u64 rootport_total_nonfatal_errs;
93 
94 	/* Ratelimits for errors */
95 	struct ratelimit_state correctable_ratelimit;
96 	struct ratelimit_state nonfatal_ratelimit;
97 };
98 
99 #define AER_LOG_TLP_MASKS		(PCI_ERR_UNC_POISON_TLP|	\
100 					PCI_ERR_UNC_POISON_BLK |	\
101 					PCI_ERR_UNC_ECRC|		\
102 					PCI_ERR_UNC_UNSUP|		\
103 					PCI_ERR_UNC_COMP_ABORT|		\
104 					PCI_ERR_UNC_UNX_COMP|		\
105 					PCI_ERR_UNC_ACSV |		\
106 					PCI_ERR_UNC_MCBTLP |		\
107 					PCI_ERR_UNC_ATOMEG |		\
108 					PCI_ERR_UNC_DMWR_BLK |		\
109 					PCI_ERR_UNC_XLAT_BLK |		\
110 					PCI_ERR_UNC_TLPPRE |		\
111 					PCI_ERR_UNC_MALF_TLP |		\
112 					PCI_ERR_UNC_IDE_CHECK |		\
113 					PCI_ERR_UNC_MISR_IDE |		\
114 					PCI_ERR_UNC_PCRC_CHECK)
115 
116 #define SYSTEM_ERROR_INTR_ON_MESG_MASK	(PCI_EXP_RTCTL_SECEE|	\
117 					PCI_EXP_RTCTL_SENFEE|	\
118 					PCI_EXP_RTCTL_SEFEE)
119 #define ROOT_PORT_INTR_ON_MESG_MASK	(PCI_ERR_ROOT_CMD_COR_EN|	\
120 					PCI_ERR_ROOT_CMD_NONFATAL_EN|	\
121 					PCI_ERR_ROOT_CMD_FATAL_EN)
122 #define ERR_COR_ID(d)			(d & 0xffff)
123 #define ERR_UNCOR_ID(d)			(d >> 16)
124 
125 #define AER_ERR_STATUS_MASK		(PCI_ERR_ROOT_UNCOR_RCV |	\
126 					PCI_ERR_ROOT_COR_RCV |		\
127 					PCI_ERR_ROOT_MULTI_COR_RCV |	\
128 					PCI_ERR_ROOT_MULTI_UNCOR_RCV)
129 
130 static bool pcie_aer_disable;
131 static pci_ers_result_t aer_root_reset(struct pci_dev *dev);
132 
133 void pci_no_aer(void)
134 {
135 	pcie_aer_disable = true;
136 }
137 
138 bool pci_aer_available(void)
139 {
140 	return !pcie_aer_disable && pci_msi_enabled();
141 }
142 
143 #ifdef CONFIG_PCIE_ECRC
144 
145 #define ECRC_POLICY_DEFAULT 0		/* ECRC set by BIOS */
146 #define ECRC_POLICY_OFF     1		/* ECRC off for performance */
147 #define ECRC_POLICY_ON      2		/* ECRC on for data integrity */
148 
149 static int ecrc_policy = ECRC_POLICY_DEFAULT;
150 
151 static const char * const ecrc_policy_str[] = {
152 	[ECRC_POLICY_DEFAULT] = "bios",
153 	[ECRC_POLICY_OFF] = "off",
154 	[ECRC_POLICY_ON] = "on"
155 };
156 
157 /**
158  * enable_ecrc_checking - enable PCIe ECRC checking for a device
159  * @dev: the PCI device
160  *
161  * Return: 0 on success, or negative on failure.
162  */
163 static int enable_ecrc_checking(struct pci_dev *dev)
164 {
165 	int aer = dev->aer_cap;
166 	u32 reg32;
167 
168 	if (!aer)
169 		return -ENODEV;
170 
171 	pci_read_config_dword(dev, aer + PCI_ERR_CAP, &reg32);
172 	if (reg32 & PCI_ERR_CAP_ECRC_GENC)
173 		reg32 |= PCI_ERR_CAP_ECRC_GENE;
174 	if (reg32 & PCI_ERR_CAP_ECRC_CHKC)
175 		reg32 |= PCI_ERR_CAP_ECRC_CHKE;
176 	pci_write_config_dword(dev, aer + PCI_ERR_CAP, reg32);
177 
178 	return 0;
179 }
180 
181 /**
182  * disable_ecrc_checking - disable PCIe ECRC checking for a device
183  * @dev: the PCI device
184  *
185  * Return: 0 on success, or negative on failure.
186  */
187 static int disable_ecrc_checking(struct pci_dev *dev)
188 {
189 	int aer = dev->aer_cap;
190 	u32 reg32;
191 
192 	if (!aer)
193 		return -ENODEV;
194 
195 	pci_read_config_dword(dev, aer + PCI_ERR_CAP, &reg32);
196 	reg32 &= ~(PCI_ERR_CAP_ECRC_GENE | PCI_ERR_CAP_ECRC_CHKE);
197 	pci_write_config_dword(dev, aer + PCI_ERR_CAP, reg32);
198 
199 	return 0;
200 }
201 
202 /**
203  * pcie_set_ecrc_checking - set/unset PCIe ECRC checking for a device based
204  * on global policy
205  * @dev: the PCI device
206  */
207 void pcie_set_ecrc_checking(struct pci_dev *dev)
208 {
209 	if (!pcie_aer_is_native(dev))
210 		return;
211 
212 	switch (ecrc_policy) {
213 	case ECRC_POLICY_DEFAULT:
214 		return;
215 	case ECRC_POLICY_OFF:
216 		disable_ecrc_checking(dev);
217 		break;
218 	case ECRC_POLICY_ON:
219 		enable_ecrc_checking(dev);
220 		break;
221 	default:
222 		return;
223 	}
224 }
225 
226 /**
227  * pcie_ecrc_get_policy - parse kernel command-line ecrc option
228  * @str: ECRC policy from kernel command line to use
229  */
230 void pcie_ecrc_get_policy(char *str)
231 {
232 	int i;
233 
234 	i = match_string(ecrc_policy_str, ARRAY_SIZE(ecrc_policy_str), str);
235 	if (i < 0)
236 		return;
237 
238 	ecrc_policy = i;
239 }
240 #endif	/* CONFIG_PCIE_ECRC */
241 
242 int pcie_aer_is_native(struct pci_dev *dev)
243 {
244 	struct pci_host_bridge *host = pci_find_host_bridge(dev->bus);
245 
246 	if (!dev->aer_cap)
247 		return 0;
248 
249 	return pcie_ports_native || host->native_aer;
250 }
251 EXPORT_SYMBOL_NS_GPL(pcie_aer_is_native, "CXL");
252 
253 static int pci_enable_pcie_error_reporting(struct pci_dev *dev)
254 {
255 	int rc;
256 
257 	if (!pcie_aer_is_native(dev))
258 		return -EIO;
259 
260 	rc = pcie_capability_set_word(dev, PCI_EXP_DEVCTL, PCI_EXP_AER_FLAGS);
261 	return pcibios_err_to_errno(rc);
262 }
263 
264 int pci_aer_clear_nonfatal_status(struct pci_dev *dev)
265 {
266 	int aer = dev->aer_cap;
267 	u32 status, sev;
268 
269 	if (!pcie_aer_is_native(dev))
270 		return -EIO;
271 
272 	/* Clear status bits for ERR_NONFATAL errors only */
273 	pci_read_config_dword(dev, aer + PCI_ERR_UNCOR_STATUS, &status);
274 	pci_read_config_dword(dev, aer + PCI_ERR_UNCOR_SEVER, &sev);
275 	status &= ~sev;
276 	if (status)
277 		pci_write_config_dword(dev, aer + PCI_ERR_UNCOR_STATUS, status);
278 
279 	return 0;
280 }
281 EXPORT_SYMBOL_GPL(pci_aer_clear_nonfatal_status);
282 
283 void pci_aer_clear_fatal_status(struct pci_dev *dev)
284 {
285 	int aer = dev->aer_cap;
286 	u32 status, sev;
287 
288 	if (!pcie_aer_is_native(dev))
289 		return;
290 
291 	/* Clear status bits for ERR_FATAL errors only */
292 	pci_read_config_dword(dev, aer + PCI_ERR_UNCOR_STATUS, &status);
293 	pci_read_config_dword(dev, aer + PCI_ERR_UNCOR_SEVER, &sev);
294 	status &= sev;
295 	if (status)
296 		pci_write_config_dword(dev, aer + PCI_ERR_UNCOR_STATUS, status);
297 }
298 
299 /**
300  * pci_aer_raw_clear_status - Clear AER error registers.
301  * @dev: the PCI device
302  *
303  * Clear AER error status registers unconditionally, regardless of
304  * whether they're owned by firmware or the OS.
305  *
306  * Return: 0 on success, or negative on failure.
307  */
308 int pci_aer_raw_clear_status(struct pci_dev *dev)
309 {
310 	int aer = dev->aer_cap;
311 	u32 status;
312 	int port_type;
313 
314 	if (!aer)
315 		return -EIO;
316 
317 	port_type = pci_pcie_type(dev);
318 	if (port_type == PCI_EXP_TYPE_ROOT_PORT ||
319 	    port_type == PCI_EXP_TYPE_RC_EC) {
320 		pci_read_config_dword(dev, aer + PCI_ERR_ROOT_STATUS, &status);
321 		pci_write_config_dword(dev, aer + PCI_ERR_ROOT_STATUS, status);
322 	}
323 
324 	pci_read_config_dword(dev, aer + PCI_ERR_COR_STATUS, &status);
325 	pci_write_config_dword(dev, aer + PCI_ERR_COR_STATUS, status);
326 
327 	pci_read_config_dword(dev, aer + PCI_ERR_UNCOR_STATUS, &status);
328 	pci_write_config_dword(dev, aer + PCI_ERR_UNCOR_STATUS, status);
329 
330 	return 0;
331 }
332 
333 int pci_aer_clear_status(struct pci_dev *dev)
334 {
335 	if (!pcie_aer_is_native(dev))
336 		return -EIO;
337 
338 	return pci_aer_raw_clear_status(dev);
339 }
340 
341 void pci_save_aer_state(struct pci_dev *dev)
342 {
343 	int aer = dev->aer_cap;
344 	struct pci_cap_saved_state *save_state;
345 	u32 *cap;
346 
347 	if (!aer)
348 		return;
349 
350 	save_state = pci_find_saved_ext_cap(dev, PCI_EXT_CAP_ID_ERR);
351 	if (!save_state)
352 		return;
353 
354 	cap = &save_state->cap.data[0];
355 	pci_read_config_dword(dev, aer + PCI_ERR_UNCOR_MASK, cap++);
356 	pci_read_config_dword(dev, aer + PCI_ERR_UNCOR_SEVER, cap++);
357 	pci_read_config_dword(dev, aer + PCI_ERR_COR_MASK, cap++);
358 	pci_read_config_dword(dev, aer + PCI_ERR_CAP, cap++);
359 	if (pcie_cap_has_rtctl(dev))
360 		pci_read_config_dword(dev, aer + PCI_ERR_ROOT_COMMAND, cap++);
361 }
362 
363 void pci_restore_aer_state(struct pci_dev *dev)
364 {
365 	int aer = dev->aer_cap;
366 	struct pci_cap_saved_state *save_state;
367 	u32 *cap;
368 
369 	if (!aer)
370 		return;
371 
372 	save_state = pci_find_saved_ext_cap(dev, PCI_EXT_CAP_ID_ERR);
373 	if (!save_state)
374 		return;
375 
376 	cap = &save_state->cap.data[0];
377 	pci_write_config_dword(dev, aer + PCI_ERR_UNCOR_MASK, *cap++);
378 	pci_write_config_dword(dev, aer + PCI_ERR_UNCOR_SEVER, *cap++);
379 	pci_write_config_dword(dev, aer + PCI_ERR_COR_MASK, *cap++);
380 	pci_write_config_dword(dev, aer + PCI_ERR_CAP, *cap++);
381 	if (pcie_cap_has_rtctl(dev))
382 		pci_write_config_dword(dev, aer + PCI_ERR_ROOT_COMMAND, *cap++);
383 }
384 
385 void pci_aer_init(struct pci_dev *dev)
386 {
387 	int n;
388 
389 	dev->aer_cap = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ERR);
390 	if (!dev->aer_cap)
391 		return;
392 
393 	dev->aer_info = kzalloc(sizeof(*dev->aer_info), GFP_KERNEL);
394 	if (!dev->aer_info) {
395 		dev->aer_cap = 0;
396 		return;
397 	}
398 
399 	ratelimit_state_init(&dev->aer_info->correctable_ratelimit,
400 			     DEFAULT_RATELIMIT_INTERVAL, DEFAULT_RATELIMIT_BURST);
401 	ratelimit_state_init(&dev->aer_info->nonfatal_ratelimit,
402 			     DEFAULT_RATELIMIT_INTERVAL, DEFAULT_RATELIMIT_BURST);
403 
404 	/*
405 	 * We save/restore PCI_ERR_UNCOR_MASK, PCI_ERR_UNCOR_SEVER,
406 	 * PCI_ERR_COR_MASK, and PCI_ERR_CAP.  Root and Root Complex Event
407 	 * Collectors also implement PCI_ERR_ROOT_COMMAND (PCIe r6.0, sec
408 	 * 7.8.4.9).
409 	 */
410 	n = pcie_cap_has_rtctl(dev) ? 5 : 4;
411 	pci_add_ext_cap_save_buffer(dev, PCI_EXT_CAP_ID_ERR, sizeof(u32) * n);
412 
413 	pci_aer_clear_status(dev);
414 
415 	if (pci_aer_available())
416 		pci_enable_pcie_error_reporting(dev);
417 
418 	pcie_set_ecrc_checking(dev);
419 }
420 
421 void pci_aer_exit(struct pci_dev *dev)
422 {
423 	kfree(dev->aer_info);
424 	dev->aer_info = NULL;
425 }
426 
427 #define AER_AGENT_RECEIVER		0
428 #define AER_AGENT_REQUESTER		1
429 #define AER_AGENT_COMPLETER		2
430 #define AER_AGENT_TRANSMITTER		3
431 
432 #define AER_AGENT_REQUESTER_MASK(t)	((t == AER_CORRECTABLE) ?	\
433 	0 : (PCI_ERR_UNC_COMP_TIME|PCI_ERR_UNC_UNSUP))
434 #define AER_AGENT_COMPLETER_MASK(t)	((t == AER_CORRECTABLE) ?	\
435 	0 : PCI_ERR_UNC_COMP_ABORT)
436 #define AER_AGENT_TRANSMITTER_MASK(t)	((t == AER_CORRECTABLE) ?	\
437 	(PCI_ERR_COR_REP_ROLL|PCI_ERR_COR_REP_TIMER) : 0)
438 
439 #define AER_GET_AGENT(t, e)						\
440 	((e & AER_AGENT_COMPLETER_MASK(t)) ? AER_AGENT_COMPLETER :	\
441 	(e & AER_AGENT_REQUESTER_MASK(t)) ? AER_AGENT_REQUESTER :	\
442 	(e & AER_AGENT_TRANSMITTER_MASK(t)) ? AER_AGENT_TRANSMITTER :	\
443 	AER_AGENT_RECEIVER)
444 
445 #define AER_PHYSICAL_LAYER_ERROR	0
446 #define AER_DATA_LINK_LAYER_ERROR	1
447 #define AER_TRANSACTION_LAYER_ERROR	2
448 
449 #define AER_PHYSICAL_LAYER_ERROR_MASK(t) ((t == AER_CORRECTABLE) ?	\
450 	PCI_ERR_COR_RCVR : 0)
451 #define AER_DATA_LINK_LAYER_ERROR_MASK(t) ((t == AER_CORRECTABLE) ?	\
452 	(PCI_ERR_COR_BAD_TLP|						\
453 	PCI_ERR_COR_BAD_DLLP|						\
454 	PCI_ERR_COR_REP_ROLL|						\
455 	PCI_ERR_COR_REP_TIMER) : PCI_ERR_UNC_DLP)
456 
457 #define AER_GET_LAYER_ERROR(t, e)					\
458 	((e & AER_PHYSICAL_LAYER_ERROR_MASK(t)) ? AER_PHYSICAL_LAYER_ERROR : \
459 	(e & AER_DATA_LINK_LAYER_ERROR_MASK(t)) ? AER_DATA_LINK_LAYER_ERROR : \
460 	AER_TRANSACTION_LAYER_ERROR)
461 
462 /*
463  * AER error strings
464  */
465 static const char * const aer_error_severity_string[] = {
466 	"Uncorrectable (Non-Fatal)",
467 	"Uncorrectable (Fatal)",
468 	"Correctable"
469 };
470 
471 static const char *aer_error_layer[] = {
472 	"Physical Layer",
473 	"Data Link Layer",
474 	"Transaction Layer"
475 };
476 
477 static const char *aer_correctable_error_string[] = {
478 	"RxErr",			/* Bit Position 0	*/
479 	NULL,
480 	NULL,
481 	NULL,
482 	NULL,
483 	NULL,
484 	"BadTLP",			/* Bit Position 6	*/
485 	"BadDLLP",			/* Bit Position 7	*/
486 	"Rollover",			/* Bit Position 8	*/
487 	NULL,
488 	NULL,
489 	NULL,
490 	"Timeout",			/* Bit Position 12	*/
491 	"NonFatalErr",			/* Bit Position 13	*/
492 	"CorrIntErr",			/* Bit Position 14	*/
493 	"HeaderOF",			/* Bit Position 15	*/
494 	NULL,				/* Bit Position 16	*/
495 	NULL,				/* Bit Position 17	*/
496 	NULL,				/* Bit Position 18	*/
497 	NULL,				/* Bit Position 19	*/
498 	NULL,				/* Bit Position 20	*/
499 	NULL,				/* Bit Position 21	*/
500 	NULL,				/* Bit Position 22	*/
501 	NULL,				/* Bit Position 23	*/
502 	NULL,				/* Bit Position 24	*/
503 	NULL,				/* Bit Position 25	*/
504 	NULL,				/* Bit Position 26	*/
505 	NULL,				/* Bit Position 27	*/
506 	NULL,				/* Bit Position 28	*/
507 	NULL,				/* Bit Position 29	*/
508 	NULL,				/* Bit Position 30	*/
509 	NULL,				/* Bit Position 31	*/
510 };
511 
512 static const char *aer_uncorrectable_error_string[] = {
513 	"Undefined",			/* Bit Position 0	*/
514 	NULL,
515 	NULL,
516 	NULL,
517 	"DLP",				/* Bit Position 4	*/
518 	"SDES",				/* Bit Position 5	*/
519 	NULL,
520 	NULL,
521 	NULL,
522 	NULL,
523 	NULL,
524 	NULL,
525 	"TLP",				/* Bit Position 12	*/
526 	"FCP",				/* Bit Position 13	*/
527 	"CmpltTO",			/* Bit Position 14	*/
528 	"CmpltAbrt",			/* Bit Position 15	*/
529 	"UnxCmplt",			/* Bit Position 16	*/
530 	"RxOF",				/* Bit Position 17	*/
531 	"MalfTLP",			/* Bit Position 18	*/
532 	"ECRC",				/* Bit Position 19	*/
533 	"UnsupReq",			/* Bit Position 20	*/
534 	"ACSViol",			/* Bit Position 21	*/
535 	"UncorrIntErr",			/* Bit Position 22	*/
536 	"BlockedTLP",			/* Bit Position 23	*/
537 	"AtomicOpBlocked",		/* Bit Position 24	*/
538 	"TLPBlockedErr",		/* Bit Position 25	*/
539 	"PoisonTLPBlocked",		/* Bit Position 26	*/
540 	"DMWrReqBlocked",		/* Bit Position 27	*/
541 	"IDECheck",			/* Bit Position 28	*/
542 	"MisIDETLP",			/* Bit Position 29	*/
543 	"PCRC_CHECK",			/* Bit Position 30	*/
544 	"TLPXlatBlocked",		/* Bit Position 31	*/
545 };
546 
547 static const char *aer_agent_string[] = {
548 	"Receiver ID",
549 	"Requester ID",
550 	"Completer ID",
551 	"Transmitter ID"
552 };
553 
554 #define aer_stats_dev_attr(name, stats_array, strings_array,		\
555 			   total_string, total_field)			\
556 	static ssize_t							\
557 	name##_show(struct device *dev, struct device_attribute *attr,	\
558 		     char *buf)						\
559 {									\
560 	unsigned int i;							\
561 	struct pci_dev *pdev = to_pci_dev(dev);				\
562 	u64 *stats = pdev->aer_info->stats_array;			\
563 	size_t len = 0;							\
564 									\
565 	for (i = 0; i < ARRAY_SIZE(pdev->aer_info->stats_array); i++) {	\
566 		if (strings_array[i])					\
567 			len += sysfs_emit_at(buf, len, "%s %llu\n",	\
568 					     strings_array[i],		\
569 					     stats[i]);			\
570 		else if (stats[i])					\
571 			len += sysfs_emit_at(buf, len,			\
572 					     #stats_array "_bit[%d] %llu\n",\
573 					     i, stats[i]);		\
574 	}								\
575 	len += sysfs_emit_at(buf, len, "TOTAL_%s %llu\n", total_string,	\
576 			     pdev->aer_info->total_field);		\
577 	return len;							\
578 }									\
579 static DEVICE_ATTR_RO(name)
580 
581 aer_stats_dev_attr(aer_dev_correctable, dev_cor_errs,
582 		   aer_correctable_error_string, "ERR_COR",
583 		   dev_total_cor_errs);
584 aer_stats_dev_attr(aer_dev_fatal, dev_fatal_errs,
585 		   aer_uncorrectable_error_string, "ERR_FATAL",
586 		   dev_total_fatal_errs);
587 aer_stats_dev_attr(aer_dev_nonfatal, dev_nonfatal_errs,
588 		   aer_uncorrectable_error_string, "ERR_NONFATAL",
589 		   dev_total_nonfatal_errs);
590 
591 #define aer_stats_rootport_attr(name, field)				\
592 	static ssize_t							\
593 	name##_show(struct device *dev, struct device_attribute *attr,	\
594 		     char *buf)						\
595 {									\
596 	struct pci_dev *pdev = to_pci_dev(dev);				\
597 	return sysfs_emit(buf, "%llu\n", pdev->aer_info->field);	\
598 }									\
599 static DEVICE_ATTR_RO(name)
600 
601 aer_stats_rootport_attr(aer_rootport_total_err_cor,
602 			 rootport_total_cor_errs);
603 aer_stats_rootport_attr(aer_rootport_total_err_fatal,
604 			 rootport_total_fatal_errs);
605 aer_stats_rootport_attr(aer_rootport_total_err_nonfatal,
606 			 rootport_total_nonfatal_errs);
607 
608 static struct attribute *aer_stats_attrs[] __ro_after_init = {
609 	&dev_attr_aer_dev_correctable.attr,
610 	&dev_attr_aer_dev_fatal.attr,
611 	&dev_attr_aer_dev_nonfatal.attr,
612 	&dev_attr_aer_rootport_total_err_cor.attr,
613 	&dev_attr_aer_rootport_total_err_fatal.attr,
614 	&dev_attr_aer_rootport_total_err_nonfatal.attr,
615 	NULL
616 };
617 
618 static umode_t aer_stats_attrs_are_visible(struct kobject *kobj,
619 					   struct attribute *a, int n)
620 {
621 	struct device *dev = kobj_to_dev(kobj);
622 	struct pci_dev *pdev = to_pci_dev(dev);
623 
624 	if (!pdev->aer_info)
625 		return 0;
626 
627 	if ((a == &dev_attr_aer_rootport_total_err_cor.attr ||
628 	     a == &dev_attr_aer_rootport_total_err_fatal.attr ||
629 	     a == &dev_attr_aer_rootport_total_err_nonfatal.attr) &&
630 	    ((pci_pcie_type(pdev) != PCI_EXP_TYPE_ROOT_PORT) &&
631 	     (pci_pcie_type(pdev) != PCI_EXP_TYPE_RC_EC)))
632 		return 0;
633 
634 	return a->mode;
635 }
636 
637 const struct attribute_group aer_stats_attr_group = {
638 	.attrs  = aer_stats_attrs,
639 	.is_visible = aer_stats_attrs_are_visible,
640 };
641 
642 /*
643  * Ratelimit interval
644  * <=0: disabled with ratelimit.interval = 0
645  * >0: enabled with ratelimit.interval in ms
646  */
647 #define aer_ratelimit_interval_attr(name, ratelimit)			\
648 	static ssize_t							\
649 	name##_show(struct device *dev, struct device_attribute *attr,	\
650 					 char *buf)			\
651 	{								\
652 		struct pci_dev *pdev = to_pci_dev(dev);			\
653 									\
654 		return sysfs_emit(buf, "%d\n",				\
655 				  pdev->aer_info->ratelimit.interval);	\
656 	}								\
657 									\
658 	static ssize_t							\
659 	name##_store(struct device *dev, struct device_attribute *attr, \
660 		     const char *buf, size_t count) 			\
661 	{								\
662 		struct pci_dev *pdev = to_pci_dev(dev);			\
663 		int interval;						\
664 									\
665 		if (!capable(CAP_SYS_ADMIN))				\
666 			return -EPERM;					\
667 									\
668 		if (kstrtoint(buf, 0, &interval) < 0)			\
669 			return -EINVAL;					\
670 									\
671 		if (interval <= 0)					\
672 			interval = 0;					\
673 		else							\
674 			interval = msecs_to_jiffies(interval); 		\
675 									\
676 		pdev->aer_info->ratelimit.interval = interval;		\
677 									\
678 		return count;						\
679 	}								\
680 	static DEVICE_ATTR_RW(name);
681 
682 #define aer_ratelimit_burst_attr(name, ratelimit)			\
683 	static ssize_t							\
684 	name##_show(struct device *dev, struct device_attribute *attr,	\
685 		    char *buf)						\
686 	{								\
687 		struct pci_dev *pdev = to_pci_dev(dev);			\
688 									\
689 		return sysfs_emit(buf, "%d\n",				\
690 				  pdev->aer_info->ratelimit.burst);	\
691 	}								\
692 									\
693 	static ssize_t							\
694 	name##_store(struct device *dev, struct device_attribute *attr,	\
695 		     const char *buf, size_t count)			\
696 	{								\
697 		struct pci_dev *pdev = to_pci_dev(dev);			\
698 		int burst;						\
699 									\
700 		if (!capable(CAP_SYS_ADMIN))				\
701 			return -EPERM;					\
702 									\
703 		if (kstrtoint(buf, 0, &burst) < 0)			\
704 			return -EINVAL;					\
705 									\
706 		pdev->aer_info->ratelimit.burst = burst;		\
707 									\
708 		return count;						\
709 	}								\
710 	static DEVICE_ATTR_RW(name);
711 
712 #define aer_ratelimit_attrs(name)					\
713 	aer_ratelimit_interval_attr(name##_ratelimit_interval_ms,	\
714 				    name##_ratelimit)			\
715 	aer_ratelimit_burst_attr(name##_ratelimit_burst,		\
716 				 name##_ratelimit)
717 
718 aer_ratelimit_attrs(correctable)
719 aer_ratelimit_attrs(nonfatal)
720 
721 static struct attribute *aer_attrs[] = {
722 	&dev_attr_correctable_ratelimit_interval_ms.attr,
723 	&dev_attr_correctable_ratelimit_burst.attr,
724 	&dev_attr_nonfatal_ratelimit_interval_ms.attr,
725 	&dev_attr_nonfatal_ratelimit_burst.attr,
726 	NULL
727 };
728 
729 static umode_t aer_attrs_are_visible(struct kobject *kobj,
730 				     struct attribute *a, int n)
731 {
732 	struct device *dev = kobj_to_dev(kobj);
733 	struct pci_dev *pdev = to_pci_dev(dev);
734 
735 	if (!pdev->aer_info)
736 		return 0;
737 
738 	return a->mode;
739 }
740 
741 const struct attribute_group aer_attr_group = {
742 	.name = "aer",
743 	.attrs = aer_attrs,
744 	.is_visible = aer_attrs_are_visible,
745 };
746 
747 static void pci_dev_aer_stats_incr(struct pci_dev *pdev,
748 				   struct aer_err_info *info)
749 {
750 	unsigned long status = info->status & ~info->mask;
751 	int i, max = -1;
752 	u64 *counter = NULL;
753 	struct aer_info *aer_info = pdev->aer_info;
754 
755 	if (!aer_info)
756 		return;
757 
758 	switch (info->severity) {
759 	case AER_CORRECTABLE:
760 		aer_info->dev_total_cor_errs++;
761 		counter = &aer_info->dev_cor_errs[0];
762 		max = AER_MAX_TYPEOF_COR_ERRS;
763 		break;
764 	case AER_NONFATAL:
765 		aer_info->dev_total_nonfatal_errs++;
766 		hwerr_log_error_type(HWERR_RECOV_PCI);
767 		counter = &aer_info->dev_nonfatal_errs[0];
768 		max = AER_MAX_TYPEOF_UNCOR_ERRS;
769 		break;
770 	case AER_FATAL:
771 		aer_info->dev_total_fatal_errs++;
772 		counter = &aer_info->dev_fatal_errs[0];
773 		max = AER_MAX_TYPEOF_UNCOR_ERRS;
774 		break;
775 	}
776 
777 	for_each_set_bit(i, &status, max)
778 		counter[i]++;
779 }
780 
781 static void pci_rootport_aer_stats_incr(struct pci_dev *pdev,
782 				 struct aer_err_source *e_src)
783 {
784 	struct aer_info *aer_info = pdev->aer_info;
785 
786 	if (!aer_info)
787 		return;
788 
789 	if (e_src->status & PCI_ERR_ROOT_COR_RCV)
790 		aer_info->rootport_total_cor_errs++;
791 
792 	if (e_src->status & PCI_ERR_ROOT_UNCOR_RCV) {
793 		if (e_src->status & PCI_ERR_ROOT_FATAL_RCV)
794 			aer_info->rootport_total_fatal_errs++;
795 		else
796 			aer_info->rootport_total_nonfatal_errs++;
797 	}
798 }
799 
800 static int aer_ratelimit(struct pci_dev *dev, unsigned int severity)
801 {
802 	if (!dev->aer_info)
803 		return 1;
804 
805 	switch (severity) {
806 	case AER_NONFATAL:
807 		return __ratelimit(&dev->aer_info->nonfatal_ratelimit);
808 	case AER_CORRECTABLE:
809 		return __ratelimit(&dev->aer_info->correctable_ratelimit);
810 	default:
811 		return 1;	/* Don't ratelimit fatal errors */
812 	}
813 }
814 
815 static bool tlp_header_logged(u32 status, u32 capctl)
816 {
817 	/* Errors for which a header is always logged (PCIe r7.0 sec 6.2.7) */
818 	if (status & AER_LOG_TLP_MASKS)
819 		return true;
820 
821 	/* Completion Timeout header is only logged on capable devices */
822 	if (status & PCI_ERR_UNC_COMP_TIME &&
823 	    capctl & PCI_ERR_CAP_COMP_TIME_LOG)
824 		return true;
825 
826 	return false;
827 }
828 
829 static void __aer_print_error(struct pci_dev *dev, struct aer_err_info *info)
830 {
831 	const char **strings;
832 	unsigned long status = info->status & ~info->mask;
833 	const char *level = info->level;
834 	const char *errmsg;
835 	int i;
836 
837 	if (info->severity == AER_CORRECTABLE)
838 		strings = aer_correctable_error_string;
839 	else
840 		strings = aer_uncorrectable_error_string;
841 
842 	for_each_set_bit(i, &status, 32) {
843 		errmsg = strings[i];
844 		if (!errmsg)
845 			errmsg = "Unknown Error Bit";
846 
847 		aer_printk(level, dev, "   [%2d] %-22s%s\n", i, errmsg,
848 				info->first_error == i ? " (First)" : "");
849 	}
850 }
851 
852 static void aer_print_source(struct pci_dev *dev, struct aer_err_info *info,
853 			     bool found)
854 {
855 	u16 source = info->id;
856 
857 	pci_info(dev, "%s%s error message received from %04x:%02x:%02x.%d%s\n",
858 		 info->multi_error_valid ? "Multiple " : "",
859 		 aer_error_severity_string[info->severity],
860 		 pci_domain_nr(dev->bus), PCI_BUS_NUM(source),
861 		 PCI_SLOT(source), PCI_FUNC(source),
862 		 found ? "" : " (no details found");
863 }
864 
865 void aer_print_error(struct aer_err_info *info, int i)
866 {
867 	struct pci_dev *dev;
868 	int layer, agent, id;
869 	const char *level = info->level;
870 	const char *bus_type = aer_err_bus(info);
871 
872 	if (WARN_ON_ONCE(i >= AER_MAX_MULTI_ERR_DEVICES))
873 		return;
874 
875 	dev = info->dev[i];
876 	id = pci_dev_id(dev);
877 
878 	pci_dev_aer_stats_incr(dev, info);
879 	trace_aer_event(pci_name(dev), (info->status & ~info->mask),
880 			info->severity, info->tlp_header_valid, &info->tlp, bus_type);
881 
882 	if (!info->ratelimit_print[i])
883 		return;
884 
885 	if (!info->status) {
886 		pci_err(dev, "%s Bus Error: severity=%s, type=Inaccessible, (Unregistered Agent ID)\n",
887 			bus_type, aer_error_severity_string[info->severity]);
888 		goto out;
889 	}
890 
891 	layer = AER_GET_LAYER_ERROR(info->severity, info->status);
892 	agent = AER_GET_AGENT(info->severity, info->status);
893 
894 	aer_printk(level, dev, "%s Bus Error: severity=%s, type=%s, (%s)\n",
895 		   bus_type, aer_error_severity_string[info->severity],
896 		   aer_error_layer[layer], aer_agent_string[agent]);
897 
898 	aer_printk(level, dev, "  device [%04x:%04x] error status/mask=%08x/%08x\n",
899 		   dev->vendor, dev->device, info->status, info->mask);
900 
901 	__aer_print_error(dev, info);
902 
903 	if (info->tlp_header_valid)
904 		pcie_print_tlp_log(dev, &info->tlp, level, dev_fmt("  "));
905 
906 out:
907 	if (info->id && info->error_dev_num > 1 && info->id == id)
908 		pci_err(dev, "  Error of this Agent is reported first\n");
909 }
910 
911 #ifdef CONFIG_ACPI_APEI_PCIEAER
912 int cper_severity_to_aer(int cper_severity)
913 {
914 	switch (cper_severity) {
915 	case CPER_SEV_RECOVERABLE:
916 		return AER_NONFATAL;
917 	case CPER_SEV_FATAL:
918 		return AER_FATAL;
919 	default:
920 		return AER_CORRECTABLE;
921 	}
922 }
923 EXPORT_SYMBOL_GPL(cper_severity_to_aer);
924 #endif
925 
926 void pci_print_aer(struct pci_dev *dev, int aer_severity,
927 		   struct aer_capability_regs *aer)
928 {
929 	const char *bus_type;
930 	int layer, agent, tlp_header_valid = 0;
931 	u32 status, mask;
932 	struct aer_err_info info = {
933 		.severity = aer_severity,
934 		.first_error = PCI_ERR_CAP_FEP(aer->cap_control),
935 	};
936 
937 	if (aer_severity == AER_CORRECTABLE) {
938 		status = aer->cor_status;
939 		mask = aer->cor_mask;
940 		info.level = KERN_WARNING;
941 	} else {
942 		status = aer->uncor_status;
943 		mask = aer->uncor_mask;
944 		info.level = KERN_ERR;
945 		tlp_header_valid = tlp_header_logged(status, aer->cap_control);
946 	}
947 
948 	info.status = status;
949 	info.mask = mask;
950 	info.is_cxl = pcie_is_cxl(dev);
951 
952 	bus_type = aer_err_bus(&info);
953 
954 	pci_dev_aer_stats_incr(dev, &info);
955 	trace_aer_event(pci_name(dev), (status & ~mask), aer_severity,
956 			tlp_header_valid, &aer->header_log, bus_type);
957 
958 	if (!aer_ratelimit(dev, info.severity))
959 		return;
960 
961 	layer = AER_GET_LAYER_ERROR(aer_severity, status);
962 	agent = AER_GET_AGENT(aer_severity, status);
963 
964 	aer_printk(info.level, dev, "aer_status: 0x%08x, aer_mask: 0x%08x\n",
965 		   status, mask);
966 	__aer_print_error(dev, &info);
967 	aer_printk(info.level, dev, "aer_layer=%s, aer_agent=%s\n",
968 		   aer_error_layer[layer], aer_agent_string[agent]);
969 
970 	if (aer_severity != AER_CORRECTABLE)
971 		aer_printk(info.level, dev, "aer_uncor_severity: 0x%08x\n",
972 			   aer->uncor_severity);
973 
974 	if (tlp_header_valid)
975 		pcie_print_tlp_log(dev, &aer->header_log, info.level,
976 				   dev_fmt("  "));
977 }
978 EXPORT_SYMBOL_GPL(pci_print_aer);
979 
980 /**
981  * add_error_device - list device to be handled
982  * @e_info: pointer to error info
983  * @dev: pointer to pci_dev to be added
984  */
985 static int add_error_device(struct aer_err_info *e_info, struct pci_dev *dev)
986 {
987 	int i = e_info->error_dev_num;
988 
989 	if (i >= AER_MAX_MULTI_ERR_DEVICES)
990 		return -ENOSPC;
991 
992 	e_info->dev[i] = pci_dev_get(dev);
993 	e_info->error_dev_num++;
994 
995 	/*
996 	 * Ratelimit AER log messages.  "dev" is either the source
997 	 * identified by the root's Error Source ID or it has an unmasked
998 	 * error logged in its own AER Capability.  Messages are emitted
999 	 * when "ratelimit_print[i]" is non-zero.  If we will print detail
1000 	 * for a downstream device, make sure we print the Error Source ID
1001 	 * from the root as well.
1002 	 */
1003 	if (aer_ratelimit(dev, e_info->severity)) {
1004 		e_info->ratelimit_print[i] = 1;
1005 		e_info->root_ratelimit_print = 1;
1006 	}
1007 	return 0;
1008 }
1009 
1010 /**
1011  * is_error_source - check whether the device is source of reported error
1012  * @dev: pointer to pci_dev to be checked
1013  * @e_info: pointer to reported error info
1014  */
1015 static bool is_error_source(struct pci_dev *dev, struct aer_err_info *e_info)
1016 {
1017 	int aer = dev->aer_cap;
1018 	u32 status, mask;
1019 	u16 reg16;
1020 
1021 	/*
1022 	 * When bus ID is equal to 0, it might be a bad ID
1023 	 * reported by Root Port.
1024 	 */
1025 	if ((PCI_BUS_NUM(e_info->id) != 0) &&
1026 	    !(dev->bus->bus_flags & PCI_BUS_FLAGS_NO_AERSID)) {
1027 		/* Device ID match? */
1028 		if (e_info->id == pci_dev_id(dev))
1029 			return true;
1030 
1031 		/* Continue ID comparing if there is no multiple error */
1032 		if (!e_info->multi_error_valid)
1033 			return false;
1034 	}
1035 
1036 	/*
1037 	 * When either
1038 	 *      1) bus ID is equal to 0. Some ports might lose the bus
1039 	 *              ID of error source id;
1040 	 *      2) bus flag PCI_BUS_FLAGS_NO_AERSID is set
1041 	 *      3) There are multiple errors and prior ID comparing fails;
1042 	 * We check AER status registers to find possible reporter.
1043 	 */
1044 	if (atomic_read(&dev->enable_cnt) == 0)
1045 		return false;
1046 
1047 	/* Check if AER is enabled */
1048 	pcie_capability_read_word(dev, PCI_EXP_DEVCTL, &reg16);
1049 	if (!(reg16 & PCI_EXP_AER_FLAGS))
1050 		return false;
1051 
1052 	if (!aer)
1053 		return false;
1054 
1055 	/* Check if error is recorded */
1056 	if (e_info->severity == AER_CORRECTABLE) {
1057 		pci_read_config_dword(dev, aer + PCI_ERR_COR_STATUS, &status);
1058 		pci_read_config_dword(dev, aer + PCI_ERR_COR_MASK, &mask);
1059 	} else {
1060 		pci_read_config_dword(dev, aer + PCI_ERR_UNCOR_STATUS, &status);
1061 		pci_read_config_dword(dev, aer + PCI_ERR_UNCOR_MASK, &mask);
1062 	}
1063 	if (status & ~mask)
1064 		return true;
1065 
1066 	return false;
1067 }
1068 
1069 static int find_device_iter(struct pci_dev *dev, void *data)
1070 {
1071 	struct aer_err_info *e_info = (struct aer_err_info *)data;
1072 
1073 	if (is_error_source(dev, e_info)) {
1074 		/* List this device */
1075 		if (add_error_device(e_info, dev)) {
1076 			/* We cannot handle more... Stop iteration */
1077 			pci_err(dev, "Exceeded max supported (%d) devices with errors logged\n",
1078 				AER_MAX_MULTI_ERR_DEVICES);
1079 			return 1;
1080 		}
1081 
1082 		/* If there is only a single error, stop iteration */
1083 		if (!e_info->multi_error_valid)
1084 			return 1;
1085 	}
1086 	return 0;
1087 }
1088 
1089 /**
1090  * find_source_device - search through device hierarchy for source device
1091  * @parent: pointer to Root Port pci_dev data structure
1092  * @e_info: including detailed error information such as ID
1093  *
1094  * Return: true if found.
1095  *
1096  * Invoked by DPC when error is detected at the Root Port.
1097  * Caller of this function must set id, severity, and multi_error_valid of
1098  * struct aer_err_info pointed by @e_info properly.  This function must fill
1099  * e_info->error_dev_num and e_info->dev[], based on the given information.
1100  */
1101 static bool find_source_device(struct pci_dev *parent,
1102 			       struct aer_err_info *e_info)
1103 {
1104 	struct pci_dev *dev = parent;
1105 	int result;
1106 
1107 	/* Must reset in this function */
1108 	e_info->error_dev_num = 0;
1109 
1110 	/* Is Root Port an agent that sends error message? */
1111 	result = find_device_iter(dev, e_info);
1112 	if (result)
1113 		return true;
1114 
1115 	if (pci_pcie_type(parent) == PCI_EXP_TYPE_RC_EC)
1116 		pcie_walk_rcec(parent, find_device_iter, e_info);
1117 	else
1118 		pci_walk_bus(parent->subordinate, find_device_iter, e_info);
1119 
1120 	if (!e_info->error_dev_num)
1121 		return false;
1122 	return true;
1123 }
1124 
1125 /**
1126  * pci_aer_unmask_internal_errors - unmask internal errors
1127  * @dev: pointer to the pci_dev data structure
1128  *
1129  * Unmask internal errors in the Uncorrectable and Correctable Error
1130  * Mask registers.
1131  *
1132  * Note: AER must be enabled and supported by the device which must be
1133  * checked in advance, e.g. with pcie_aer_is_native().
1134  */
1135 void pci_aer_unmask_internal_errors(struct pci_dev *dev)
1136 {
1137 	int aer = dev->aer_cap;
1138 	u32 mask;
1139 
1140 	pci_read_config_dword(dev, aer + PCI_ERR_UNCOR_MASK, &mask);
1141 	mask &= ~PCI_ERR_UNC_INTN;
1142 	pci_write_config_dword(dev, aer + PCI_ERR_UNCOR_MASK, mask);
1143 
1144 	pci_read_config_dword(dev, aer + PCI_ERR_COR_MASK, &mask);
1145 	mask &= ~PCI_ERR_COR_INTERNAL;
1146 	pci_write_config_dword(dev, aer + PCI_ERR_COR_MASK, mask);
1147 }
1148 
1149 /*
1150  * Internal errors are too device-specific to enable generally, however for CXL
1151  * their behavior is standardized for conveying CXL protocol errors.
1152  */
1153 EXPORT_SYMBOL_FOR_MODULES(pci_aer_unmask_internal_errors, "cxl_core");
1154 
1155 #ifdef CONFIG_CXL_RAS
1156 bool is_aer_internal_error(struct aer_err_info *info)
1157 {
1158 	if (info->severity == AER_CORRECTABLE)
1159 		return info->status & PCI_ERR_COR_INTERNAL;
1160 
1161 	return info->status & PCI_ERR_UNC_INTN;
1162 }
1163 #endif
1164 
1165 /**
1166  * pci_aer_handle_error - handle logging error into an event log
1167  * @dev: pointer to pci_dev data structure of error source device
1168  * @info: comprehensive error information
1169  *
1170  * Invoked when an error being detected by Root Port.
1171  */
1172 static void pci_aer_handle_error(struct pci_dev *dev, struct aer_err_info *info)
1173 {
1174 	int aer = dev->aer_cap;
1175 
1176 	if (info->severity == AER_CORRECTABLE) {
1177 		/*
1178 		 * Correctable error does not need software intervention.
1179 		 * No need to go through error recovery process.
1180 		 */
1181 		if (aer)
1182 			pci_write_config_dword(dev, aer + PCI_ERR_COR_STATUS,
1183 					info->status);
1184 		if (pcie_aer_is_native(dev)) {
1185 			struct pci_driver *pdrv = dev->driver;
1186 
1187 			if (pdrv && pdrv->err_handler &&
1188 			    pdrv->err_handler->cor_error_detected)
1189 				pdrv->err_handler->cor_error_detected(dev);
1190 			pcie_clear_device_status(dev);
1191 		}
1192 	} else if (info->severity == AER_NONFATAL)
1193 		pcie_do_recovery(dev, pci_channel_io_normal, aer_root_reset);
1194 	else if (info->severity == AER_FATAL)
1195 		pcie_do_recovery(dev, pci_channel_io_frozen, aer_root_reset);
1196 }
1197 
1198 static void handle_error_source(struct pci_dev *dev, struct aer_err_info *info)
1199 {
1200 	cxl_rch_handle_error(dev, info);
1201 	pci_aer_handle_error(dev, info);
1202 	pci_dev_put(dev);
1203 }
1204 
1205 #ifdef CONFIG_ACPI_APEI_PCIEAER
1206 
1207 #define AER_RECOVER_RING_SIZE		16
1208 
1209 struct aer_recover_entry {
1210 	u8	bus;
1211 	u8	devfn;
1212 	u16	domain;
1213 	int	severity;
1214 	struct aer_capability_regs *regs;
1215 };
1216 
1217 static DEFINE_KFIFO(aer_recover_ring, struct aer_recover_entry,
1218 		    AER_RECOVER_RING_SIZE);
1219 
1220 static void aer_recover_work_func(struct work_struct *work)
1221 {
1222 	struct aer_recover_entry entry;
1223 	struct pci_dev *pdev;
1224 
1225 	while (kfifo_get(&aer_recover_ring, &entry)) {
1226 		pdev = pci_get_domain_bus_and_slot(entry.domain, entry.bus,
1227 						   entry.devfn);
1228 		if (!pdev) {
1229 			pr_err_ratelimited("%04x:%02x:%02x.%x: no pci_dev found\n",
1230 					   entry.domain, entry.bus,
1231 					   PCI_SLOT(entry.devfn),
1232 					   PCI_FUNC(entry.devfn));
1233 			continue;
1234 		}
1235 		pci_print_aer(pdev, entry.severity, entry.regs);
1236 
1237 		/*
1238 		 * Memory for aer_capability_regs(entry.regs) is being
1239 		 * allocated from the ghes_estatus_pool to protect it from
1240 		 * overwriting when multiple sections are present in the
1241 		 * error status. Thus free the same after processing the
1242 		 * data.
1243 		 */
1244 		ghes_estatus_pool_region_free((unsigned long)entry.regs,
1245 					    sizeof(struct aer_capability_regs));
1246 
1247 		if (entry.severity == AER_NONFATAL)
1248 			pcie_do_recovery(pdev, pci_channel_io_normal,
1249 					 aer_root_reset);
1250 		else if (entry.severity == AER_FATAL)
1251 			pcie_do_recovery(pdev, pci_channel_io_frozen,
1252 					 aer_root_reset);
1253 		pci_dev_put(pdev);
1254 	}
1255 }
1256 
1257 /*
1258  * Mutual exclusion for writers of aer_recover_ring, reader side don't
1259  * need lock, because there is only one reader and lock is not needed
1260  * between reader and writer.
1261  */
1262 static DEFINE_SPINLOCK(aer_recover_ring_lock);
1263 static DECLARE_WORK(aer_recover_work, aer_recover_work_func);
1264 
1265 void aer_recover_queue(int domain, unsigned int bus, unsigned int devfn,
1266 		       int severity, struct aer_capability_regs *aer_regs)
1267 {
1268 	struct aer_recover_entry entry = {
1269 		.bus		= bus,
1270 		.devfn		= devfn,
1271 		.domain		= domain,
1272 		.severity	= severity,
1273 		.regs		= aer_regs,
1274 	};
1275 
1276 	if (kfifo_in_spinlocked(&aer_recover_ring, &entry, 1,
1277 				 &aer_recover_ring_lock))
1278 		schedule_work(&aer_recover_work);
1279 	else
1280 		pr_err("buffer overflow in recovery for %04x:%02x:%02x.%x\n",
1281 		       domain, bus, PCI_SLOT(devfn), PCI_FUNC(devfn));
1282 }
1283 EXPORT_SYMBOL_GPL(aer_recover_queue);
1284 #endif
1285 
1286 /**
1287  * aer_get_device_error_info - read error status from dev and store it to info
1288  * @info: pointer to structure to store the error record
1289  * @i: index into info->dev[]
1290  *
1291  * Return: 1 on success, 0 on error.
1292  *
1293  * Note that @info is reused among all error devices. Clear fields properly.
1294  */
1295 int aer_get_device_error_info(struct aer_err_info *info, int i)
1296 {
1297 	struct pci_dev *dev;
1298 	int type, aer;
1299 	u32 aercc;
1300 
1301 	if (i >= AER_MAX_MULTI_ERR_DEVICES)
1302 		return 0;
1303 
1304 	dev = info->dev[i];
1305 	aer = dev->aer_cap;
1306 	type = pci_pcie_type(dev);
1307 
1308 	/* Must reset in this function */
1309 	info->status = 0;
1310 	info->tlp_header_valid = 0;
1311 	info->is_cxl = pcie_is_cxl(dev);
1312 
1313 	/* The device might not support AER */
1314 	if (!aer)
1315 		return 0;
1316 
1317 	if (info->severity == AER_CORRECTABLE) {
1318 		pci_read_config_dword(dev, aer + PCI_ERR_COR_STATUS,
1319 			&info->status);
1320 		pci_read_config_dword(dev, aer + PCI_ERR_COR_MASK,
1321 			&info->mask);
1322 		if (!(info->status & ~info->mask))
1323 			return 0;
1324 	} else if (type == PCI_EXP_TYPE_ROOT_PORT ||
1325 		   type == PCI_EXP_TYPE_RC_EC ||
1326 		   type == PCI_EXP_TYPE_DOWNSTREAM ||
1327 		   info->severity == AER_NONFATAL) {
1328 
1329 		/* Link is still healthy for IO reads */
1330 		pci_read_config_dword(dev, aer + PCI_ERR_UNCOR_STATUS,
1331 			&info->status);
1332 		pci_read_config_dword(dev, aer + PCI_ERR_UNCOR_MASK,
1333 			&info->mask);
1334 		if (!(info->status & ~info->mask))
1335 			return 0;
1336 
1337 		/* Get First Error Pointer */
1338 		pci_read_config_dword(dev, aer + PCI_ERR_CAP, &aercc);
1339 		info->first_error = PCI_ERR_CAP_FEP(aercc);
1340 
1341 		if (tlp_header_logged(info->status, aercc)) {
1342 			info->tlp_header_valid = 1;
1343 			pcie_read_tlp_log(dev, aer + PCI_ERR_HEADER_LOG,
1344 					  aer + PCI_ERR_PREFIX_LOG,
1345 					  aer_tlp_log_len(dev, aercc),
1346 					  aercc & PCI_ERR_CAP_TLP_LOG_FLIT,
1347 					  &info->tlp);
1348 		}
1349 	}
1350 
1351 	return 1;
1352 }
1353 
1354 static inline void aer_process_err_devices(struct aer_err_info *e_info)
1355 {
1356 	int i;
1357 
1358 	/* Report all before handling them, to not lose records by reset etc. */
1359 	for (i = 0; i < e_info->error_dev_num && e_info->dev[i]; i++) {
1360 		if (aer_get_device_error_info(e_info, i))
1361 			aer_print_error(e_info, i);
1362 	}
1363 	for (i = 0; i < e_info->error_dev_num && e_info->dev[i]; i++) {
1364 		if (aer_get_device_error_info(e_info, i))
1365 			handle_error_source(e_info->dev[i], e_info);
1366 	}
1367 }
1368 
1369 /**
1370  * aer_isr_one_error_type - consume a Correctable or Uncorrectable Error
1371  *			    detected by Root Port or RCEC
1372  * @root: pointer to Root Port or RCEC that signaled AER interrupt
1373  * @info: pointer to AER error info
1374  */
1375 static void aer_isr_one_error_type(struct pci_dev *root,
1376 				   struct aer_err_info *info)
1377 {
1378 	bool found;
1379 
1380 	found = find_source_device(root, info);
1381 
1382 	/*
1383 	 * If we're going to log error messages, we've already set
1384 	 * "info->root_ratelimit_print" and "info->ratelimit_print[i]" to
1385 	 * non-zero (which enables printing) because this is either an
1386 	 * ERR_FATAL or we found a device with an error logged in its AER
1387 	 * Capability.
1388 	 *
1389 	 * If we didn't find the Error Source device, at least log the
1390 	 * Requester ID from the ERR_* Message received by the Root Port or
1391 	 * RCEC, ratelimited by the RP or RCEC.
1392 	 */
1393 	if (info->root_ratelimit_print ||
1394 	    (!found && aer_ratelimit(root, info->severity)))
1395 		aer_print_source(root, info, found);
1396 
1397 	if (found)
1398 		aer_process_err_devices(info);
1399 }
1400 
1401 /**
1402  * aer_isr_one_error - consume error(s) signaled by an AER interrupt from
1403  *		       Root Port or RCEC
1404  * @root: pointer to Root Port or RCEC that signaled AER interrupt
1405  * @e_src: pointer to an error source
1406  */
1407 static void aer_isr_one_error(struct pci_dev *root,
1408 			      struct aer_err_source *e_src)
1409 {
1410 	u32 status = e_src->status;
1411 
1412 	pci_rootport_aer_stats_incr(root, e_src);
1413 
1414 	/*
1415 	 * There is a possibility that both correctable error and
1416 	 * uncorrectable error being logged. Report correctable error first.
1417 	 */
1418 	if (status & PCI_ERR_ROOT_COR_RCV) {
1419 		int multi = status & PCI_ERR_ROOT_MULTI_COR_RCV;
1420 		struct aer_err_info e_info = {
1421 			.id = ERR_COR_ID(e_src->id),
1422 			.severity = AER_CORRECTABLE,
1423 			.level = KERN_WARNING,
1424 			.multi_error_valid = multi ? 1 : 0,
1425 		};
1426 
1427 		aer_isr_one_error_type(root, &e_info);
1428 	}
1429 
1430 	if (status & PCI_ERR_ROOT_UNCOR_RCV) {
1431 		int fatal = status & PCI_ERR_ROOT_FATAL_RCV;
1432 		int multi = status & PCI_ERR_ROOT_MULTI_UNCOR_RCV;
1433 		struct aer_err_info e_info = {
1434 			.id = ERR_UNCOR_ID(e_src->id),
1435 			.severity = fatal ? AER_FATAL : AER_NONFATAL,
1436 			.level = KERN_ERR,
1437 			.multi_error_valid = multi ? 1 : 0,
1438 		};
1439 
1440 		aer_isr_one_error_type(root, &e_info);
1441 	}
1442 }
1443 
1444 /**
1445  * aer_isr - consume errors detected by Root Port
1446  * @irq: IRQ assigned to Root Port
1447  * @context: pointer to Root Port data structure
1448  *
1449  * Invoked, as DPC, when Root Port records new detected error
1450  */
1451 static irqreturn_t aer_isr(int irq, void *context)
1452 {
1453 	struct pcie_device *dev = (struct pcie_device *)context;
1454 	struct aer_rpc *rpc = get_service_data(dev);
1455 	struct aer_err_source e_src;
1456 
1457 	if (kfifo_is_empty(&rpc->aer_fifo))
1458 		return IRQ_NONE;
1459 
1460 	while (kfifo_get(&rpc->aer_fifo, &e_src))
1461 		aer_isr_one_error(rpc->rpd, &e_src);
1462 	return IRQ_HANDLED;
1463 }
1464 
1465 /**
1466  * aer_irq - Root Port's ISR
1467  * @irq: IRQ assigned to Root Port
1468  * @context: pointer to Root Port data structure
1469  *
1470  * Invoked when Root Port detects AER messages.
1471  */
1472 static irqreturn_t aer_irq(int irq, void *context)
1473 {
1474 	struct pcie_device *pdev = (struct pcie_device *)context;
1475 	struct aer_rpc *rpc = get_service_data(pdev);
1476 	struct pci_dev *rp = rpc->rpd;
1477 	int aer = rp->aer_cap;
1478 	struct aer_err_source e_src = {};
1479 
1480 	pci_read_config_dword(rp, aer + PCI_ERR_ROOT_STATUS, &e_src.status);
1481 	if (!(e_src.status & AER_ERR_STATUS_MASK))
1482 		return IRQ_NONE;
1483 
1484 	pci_read_config_dword(rp, aer + PCI_ERR_ROOT_ERR_SRC, &e_src.id);
1485 	pci_write_config_dword(rp, aer + PCI_ERR_ROOT_STATUS, e_src.status);
1486 
1487 	if (!kfifo_put(&rpc->aer_fifo, e_src))
1488 		return IRQ_HANDLED;
1489 
1490 	return IRQ_WAKE_THREAD;
1491 }
1492 
1493 static void aer_enable_irq(struct pci_dev *pdev)
1494 {
1495 	int aer = pdev->aer_cap;
1496 	u32 reg32;
1497 
1498 	/* Enable Root Port's interrupt in response to error messages */
1499 	pci_read_config_dword(pdev, aer + PCI_ERR_ROOT_COMMAND, &reg32);
1500 	reg32 |= ROOT_PORT_INTR_ON_MESG_MASK;
1501 	pci_write_config_dword(pdev, aer + PCI_ERR_ROOT_COMMAND, reg32);
1502 }
1503 
1504 static void aer_disable_irq(struct pci_dev *pdev)
1505 {
1506 	int aer = pdev->aer_cap;
1507 	u32 reg32;
1508 
1509 	/* Disable Root Port's interrupt in response to error messages */
1510 	pci_read_config_dword(pdev, aer + PCI_ERR_ROOT_COMMAND, &reg32);
1511 	reg32 &= ~ROOT_PORT_INTR_ON_MESG_MASK;
1512 	pci_write_config_dword(pdev, aer + PCI_ERR_ROOT_COMMAND, reg32);
1513 }
1514 
1515 static int clear_status_iter(struct pci_dev *dev, void *data)
1516 {
1517 	u16 devctl;
1518 
1519 	/* Skip if pci_enable_pcie_error_reporting() hasn't been called yet */
1520 	pcie_capability_read_word(dev, PCI_EXP_DEVCTL, &devctl);
1521 	if (!(devctl & PCI_EXP_AER_FLAGS))
1522 		return 0;
1523 
1524 	pci_aer_clear_status(dev);
1525 	pcie_clear_device_status(dev);
1526 	return 0;
1527 }
1528 
1529 /**
1530  * aer_enable_rootport - enable Root Port's interrupts when receiving messages
1531  * @rpc: pointer to a Root Port data structure
1532  *
1533  * Invoked when PCIe bus loads AER service driver.
1534  */
1535 static void aer_enable_rootport(struct aer_rpc *rpc)
1536 {
1537 	struct pci_dev *pdev = rpc->rpd;
1538 	int aer = pdev->aer_cap;
1539 	u16 reg16;
1540 	u32 reg32;
1541 
1542 	/* Clear PCIe Capability's Device Status */
1543 	pcie_capability_read_word(pdev, PCI_EXP_DEVSTA, &reg16);
1544 	pcie_capability_write_word(pdev, PCI_EXP_DEVSTA, reg16);
1545 
1546 	/* Disable system error generation in response to error messages */
1547 	pcie_capability_clear_word(pdev, PCI_EXP_RTCTL,
1548 				   SYSTEM_ERROR_INTR_ON_MESG_MASK);
1549 
1550 	/* Clear error status of this Root Port or RCEC */
1551 	pci_read_config_dword(pdev, aer + PCI_ERR_ROOT_STATUS, &reg32);
1552 	pci_write_config_dword(pdev, aer + PCI_ERR_ROOT_STATUS, reg32);
1553 
1554 	/* Clear error status of agents reporting to this Root Port or RCEC */
1555 	if (reg32 & AER_ERR_STATUS_MASK) {
1556 		if (pci_pcie_type(pdev) == PCI_EXP_TYPE_RC_EC)
1557 			pcie_walk_rcec(pdev, clear_status_iter, NULL);
1558 		else if (pdev->subordinate)
1559 			pci_walk_bus(pdev->subordinate, clear_status_iter,
1560 				     NULL);
1561 	}
1562 
1563 	pci_read_config_dword(pdev, aer + PCI_ERR_COR_STATUS, &reg32);
1564 	pci_write_config_dword(pdev, aer + PCI_ERR_COR_STATUS, reg32);
1565 	pci_read_config_dword(pdev, aer + PCI_ERR_UNCOR_STATUS, &reg32);
1566 	pci_write_config_dword(pdev, aer + PCI_ERR_UNCOR_STATUS, reg32);
1567 
1568 	aer_enable_irq(pdev);
1569 }
1570 
1571 /**
1572  * aer_disable_rootport - disable Root Port's interrupts when receiving messages
1573  * @rpc: pointer to a Root Port data structure
1574  *
1575  * Invoked when PCIe bus unloads AER service driver.
1576  */
1577 static void aer_disable_rootport(struct aer_rpc *rpc)
1578 {
1579 	struct pci_dev *pdev = rpc->rpd;
1580 	int aer = pdev->aer_cap;
1581 	u32 reg32;
1582 
1583 	aer_disable_irq(pdev);
1584 
1585 	/* Clear Root's error status reg */
1586 	pci_read_config_dword(pdev, aer + PCI_ERR_ROOT_STATUS, &reg32);
1587 	pci_write_config_dword(pdev, aer + PCI_ERR_ROOT_STATUS, reg32);
1588 }
1589 
1590 /**
1591  * aer_remove - clean up resources
1592  * @dev: pointer to the pcie_dev data structure
1593  *
1594  * Invoked when PCI Express bus unloads or AER probe fails.
1595  */
1596 static void aer_remove(struct pcie_device *dev)
1597 {
1598 	struct aer_rpc *rpc = get_service_data(dev);
1599 
1600 	aer_disable_rootport(rpc);
1601 }
1602 
1603 /**
1604  * aer_probe - initialize resources
1605  * @dev: pointer to the pcie_dev data structure
1606  *
1607  * Invoked when PCI Express bus loads AER service driver.
1608  */
1609 static int aer_probe(struct pcie_device *dev)
1610 {
1611 	int status;
1612 	struct aer_rpc *rpc;
1613 	struct device *device = &dev->device;
1614 	struct pci_dev *port = dev->port;
1615 
1616 	BUILD_BUG_ON(ARRAY_SIZE(aer_correctable_error_string) <
1617 		     AER_MAX_TYPEOF_COR_ERRS);
1618 	BUILD_BUG_ON(ARRAY_SIZE(aer_uncorrectable_error_string) <
1619 		     AER_MAX_TYPEOF_UNCOR_ERRS);
1620 
1621 	/* Limit to Root Ports or Root Complex Event Collectors */
1622 	if ((pci_pcie_type(port) != PCI_EXP_TYPE_RC_EC) &&
1623 	    (pci_pcie_type(port) != PCI_EXP_TYPE_ROOT_PORT))
1624 		return -ENODEV;
1625 
1626 	rpc = devm_kzalloc(device, sizeof(struct aer_rpc), GFP_KERNEL);
1627 	if (!rpc)
1628 		return -ENOMEM;
1629 
1630 	rpc->rpd = port;
1631 	INIT_KFIFO(rpc->aer_fifo);
1632 	set_service_data(dev, rpc);
1633 
1634 	status = devm_request_threaded_irq(device, dev->irq, aer_irq, aer_isr,
1635 					   IRQF_SHARED, "aerdrv", dev);
1636 	if (status) {
1637 		pci_err(port, "request AER IRQ %d failed\n", dev->irq);
1638 		return status;
1639 	}
1640 
1641 	cxl_rch_enable_rcec(port);
1642 	aer_enable_rootport(rpc);
1643 	pci_info(port, "enabled with IRQ %d\n", dev->irq);
1644 	return 0;
1645 }
1646 
1647 static int aer_suspend(struct pcie_device *dev)
1648 {
1649 	struct aer_rpc *rpc = get_service_data(dev);
1650 
1651 	aer_disable_rootport(rpc);
1652 	return 0;
1653 }
1654 
1655 static int aer_resume(struct pcie_device *dev)
1656 {
1657 	struct aer_rpc *rpc = get_service_data(dev);
1658 
1659 	aer_enable_rootport(rpc);
1660 	return 0;
1661 }
1662 
1663 /**
1664  * aer_root_reset - reset Root Port hierarchy, RCEC, or RCiEP
1665  * @dev: pointer to Root Port, RCEC, or RCiEP
1666  *
1667  * Invoked by Port Bus driver when performing reset.
1668  */
1669 static pci_ers_result_t aer_root_reset(struct pci_dev *dev)
1670 {
1671 	int type = pci_pcie_type(dev);
1672 	struct pci_dev *root;
1673 	int aer;
1674 	struct pci_host_bridge *host = pci_find_host_bridge(dev->bus);
1675 	u32 reg32;
1676 	int rc;
1677 
1678 	/*
1679 	 * Only Root Ports and RCECs have AER Root Command and Root Status
1680 	 * registers.  If "dev" is an RCiEP, the relevant registers are in
1681 	 * the RCEC.
1682 	 */
1683 	if (type == PCI_EXP_TYPE_RC_END)
1684 		root = dev->rcec;
1685 	else
1686 		root = pcie_find_root_port(dev);
1687 
1688 	/*
1689 	 * If the platform retained control of AER, an RCiEP may not have
1690 	 * an RCEC visible to us, so dev->rcec ("root") may be NULL.  In
1691 	 * that case, firmware is responsible for these registers.
1692 	 */
1693 	aer = root ? root->aer_cap : 0;
1694 
1695 	if ((host->native_aer || pcie_ports_native) && aer)
1696 		aer_disable_irq(root);
1697 
1698 	if (type == PCI_EXP_TYPE_RC_EC || type == PCI_EXP_TYPE_RC_END) {
1699 		rc = pcie_reset_flr(dev, PCI_RESET_DO_RESET);
1700 		if (!rc)
1701 			pci_info(dev, "has been reset\n");
1702 		else
1703 			pci_info(dev, "not reset (no FLR support: %d)\n", rc);
1704 	} else {
1705 		rc = pci_bus_error_reset(dev);
1706 		pci_info(dev, "%s Port link has been reset (%d)\n",
1707 			pci_is_root_bus(dev->bus) ? "Root" : "Downstream", rc);
1708 	}
1709 
1710 	if ((host->native_aer || pcie_ports_native) && aer) {
1711 		/* Clear Root Error Status */
1712 		pci_read_config_dword(root, aer + PCI_ERR_ROOT_STATUS, &reg32);
1713 		pci_write_config_dword(root, aer + PCI_ERR_ROOT_STATUS, reg32);
1714 
1715 		aer_enable_irq(root);
1716 	}
1717 
1718 	return rc ? PCI_ERS_RESULT_DISCONNECT : PCI_ERS_RESULT_RECOVERED;
1719 }
1720 
1721 static struct pcie_port_service_driver aerdriver = {
1722 	.name		= "aer",
1723 	.port_type	= PCIE_ANY_PORT,
1724 	.service	= PCIE_PORT_SERVICE_AER,
1725 
1726 	.probe		= aer_probe,
1727 	.suspend	= aer_suspend,
1728 	.resume		= aer_resume,
1729 	.remove		= aer_remove,
1730 };
1731 
1732 /**
1733  * pcie_aer_init - register AER service driver
1734  *
1735  * Invoked when AER service driver is loaded.
1736  */
1737 int __init pcie_aer_init(void)
1738 {
1739 	if (!pci_aer_available())
1740 		return -ENXIO;
1741 	return pcie_port_service_register(&aerdriver);
1742 }
1743