xref: /openbmc/linux/drivers/pci/pcie/aer.c (revision 5c816641)
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 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 static pci_ers_result_t aer_root_reset(struct pci_dev *dev);
106 
107 void pci_no_aer(void)
108 {
109 	pcie_aer_disable = 1;
110 }
111 
112 bool pci_aer_available(void)
113 {
114 	return !pcie_aer_disable && pci_msi_enabled();
115 }
116 
117 #ifdef CONFIG_PCIE_ECRC
118 
119 #define ECRC_POLICY_DEFAULT 0		/* ECRC set by BIOS */
120 #define ECRC_POLICY_OFF     1		/* ECRC off for performance */
121 #define ECRC_POLICY_ON      2		/* ECRC on for data integrity */
122 
123 static int ecrc_policy = ECRC_POLICY_DEFAULT;
124 
125 static const char * const ecrc_policy_str[] = {
126 	[ECRC_POLICY_DEFAULT] = "bios",
127 	[ECRC_POLICY_OFF] = "off",
128 	[ECRC_POLICY_ON] = "on"
129 };
130 
131 /**
132  * enable_ecrc_checking - enable PCIe ECRC checking for a device
133  * @dev: the PCI device
134  *
135  * Returns 0 on success, or negative on failure.
136  */
137 static int enable_ecrc_checking(struct pci_dev *dev)
138 {
139 	int aer = dev->aer_cap;
140 	u32 reg32;
141 
142 	if (!aer)
143 		return -ENODEV;
144 
145 	pci_read_config_dword(dev, aer + PCI_ERR_CAP, &reg32);
146 	if (reg32 & PCI_ERR_CAP_ECRC_GENC)
147 		reg32 |= PCI_ERR_CAP_ECRC_GENE;
148 	if (reg32 & PCI_ERR_CAP_ECRC_CHKC)
149 		reg32 |= PCI_ERR_CAP_ECRC_CHKE;
150 	pci_write_config_dword(dev, aer + PCI_ERR_CAP, reg32);
151 
152 	return 0;
153 }
154 
155 /**
156  * disable_ecrc_checking - disables PCIe ECRC checking for a device
157  * @dev: the PCI device
158  *
159  * Returns 0 on success, or negative on failure.
160  */
161 static int disable_ecrc_checking(struct pci_dev *dev)
162 {
163 	int aer = dev->aer_cap;
164 	u32 reg32;
165 
166 	if (!aer)
167 		return -ENODEV;
168 
169 	pci_read_config_dword(dev, aer + PCI_ERR_CAP, &reg32);
170 	reg32 &= ~(PCI_ERR_CAP_ECRC_GENE | PCI_ERR_CAP_ECRC_CHKE);
171 	pci_write_config_dword(dev, aer + PCI_ERR_CAP, reg32);
172 
173 	return 0;
174 }
175 
176 /**
177  * pcie_set_ecrc_checking - set/unset PCIe ECRC checking for a device based on global policy
178  * @dev: the PCI device
179  */
180 void pcie_set_ecrc_checking(struct pci_dev *dev)
181 {
182 	switch (ecrc_policy) {
183 	case ECRC_POLICY_DEFAULT:
184 		return;
185 	case ECRC_POLICY_OFF:
186 		disable_ecrc_checking(dev);
187 		break;
188 	case ECRC_POLICY_ON:
189 		enable_ecrc_checking(dev);
190 		break;
191 	default:
192 		return;
193 	}
194 }
195 
196 /**
197  * pcie_ecrc_get_policy - parse kernel command-line ecrc option
198  * @str: ECRC policy from kernel command line to use
199  */
200 void pcie_ecrc_get_policy(char *str)
201 {
202 	int i;
203 
204 	i = match_string(ecrc_policy_str, ARRAY_SIZE(ecrc_policy_str), str);
205 	if (i < 0)
206 		return;
207 
208 	ecrc_policy = i;
209 }
210 #endif	/* CONFIG_PCIE_ECRC */
211 
212 #define	PCI_EXP_AER_FLAGS	(PCI_EXP_DEVCTL_CERE | PCI_EXP_DEVCTL_NFERE | \
213 				 PCI_EXP_DEVCTL_FERE | PCI_EXP_DEVCTL_URRE)
214 
215 int pcie_aer_is_native(struct pci_dev *dev)
216 {
217 	struct pci_host_bridge *host = pci_find_host_bridge(dev->bus);
218 
219 	if (!dev->aer_cap)
220 		return 0;
221 
222 	return pcie_ports_native || host->native_aer;
223 }
224 
225 int pci_enable_pcie_error_reporting(struct pci_dev *dev)
226 {
227 	int rc;
228 
229 	if (!pcie_aer_is_native(dev))
230 		return -EIO;
231 
232 	rc = pcie_capability_set_word(dev, PCI_EXP_DEVCTL, PCI_EXP_AER_FLAGS);
233 	return pcibios_err_to_errno(rc);
234 }
235 EXPORT_SYMBOL_GPL(pci_enable_pcie_error_reporting);
236 
237 int pci_disable_pcie_error_reporting(struct pci_dev *dev)
238 {
239 	int rc;
240 
241 	if (!pcie_aer_is_native(dev))
242 		return -EIO;
243 
244 	rc = pcie_capability_clear_word(dev, PCI_EXP_DEVCTL, PCI_EXP_AER_FLAGS);
245 	return pcibios_err_to_errno(rc);
246 }
247 EXPORT_SYMBOL_GPL(pci_disable_pcie_error_reporting);
248 
249 int pci_aer_clear_nonfatal_status(struct pci_dev *dev)
250 {
251 	int aer = dev->aer_cap;
252 	u32 status, sev;
253 
254 	if (!pcie_aer_is_native(dev))
255 		return -EIO;
256 
257 	/* Clear status bits for ERR_NONFATAL errors only */
258 	pci_read_config_dword(dev, aer + PCI_ERR_UNCOR_STATUS, &status);
259 	pci_read_config_dword(dev, aer + PCI_ERR_UNCOR_SEVER, &sev);
260 	status &= ~sev;
261 	if (status)
262 		pci_write_config_dword(dev, aer + PCI_ERR_UNCOR_STATUS, status);
263 
264 	return 0;
265 }
266 EXPORT_SYMBOL_GPL(pci_aer_clear_nonfatal_status);
267 
268 void pci_aer_clear_fatal_status(struct pci_dev *dev)
269 {
270 	int aer = dev->aer_cap;
271 	u32 status, sev;
272 
273 	if (!pcie_aer_is_native(dev))
274 		return;
275 
276 	/* Clear status bits for ERR_FATAL errors only */
277 	pci_read_config_dword(dev, aer + PCI_ERR_UNCOR_STATUS, &status);
278 	pci_read_config_dword(dev, aer + PCI_ERR_UNCOR_SEVER, &sev);
279 	status &= sev;
280 	if (status)
281 		pci_write_config_dword(dev, aer + PCI_ERR_UNCOR_STATUS, status);
282 }
283 
284 /**
285  * pci_aer_raw_clear_status - Clear AER error registers.
286  * @dev: the PCI device
287  *
288  * Clearing AER error status registers unconditionally, regardless of
289  * whether they're owned by firmware or the OS.
290  *
291  * Returns 0 on success, or negative on failure.
292  */
293 int pci_aer_raw_clear_status(struct pci_dev *dev)
294 {
295 	int aer = dev->aer_cap;
296 	u32 status;
297 	int port_type;
298 
299 	if (!aer)
300 		return -EIO;
301 
302 	port_type = pci_pcie_type(dev);
303 	if (port_type == PCI_EXP_TYPE_ROOT_PORT ||
304 	    port_type == PCI_EXP_TYPE_RC_EC) {
305 		pci_read_config_dword(dev, aer + PCI_ERR_ROOT_STATUS, &status);
306 		pci_write_config_dword(dev, aer + PCI_ERR_ROOT_STATUS, status);
307 	}
308 
309 	pci_read_config_dword(dev, aer + PCI_ERR_COR_STATUS, &status);
310 	pci_write_config_dword(dev, aer + PCI_ERR_COR_STATUS, status);
311 
312 	pci_read_config_dword(dev, aer + PCI_ERR_UNCOR_STATUS, &status);
313 	pci_write_config_dword(dev, aer + PCI_ERR_UNCOR_STATUS, status);
314 
315 	return 0;
316 }
317 
318 int pci_aer_clear_status(struct pci_dev *dev)
319 {
320 	if (!pcie_aer_is_native(dev))
321 		return -EIO;
322 
323 	return pci_aer_raw_clear_status(dev);
324 }
325 
326 void pci_save_aer_state(struct pci_dev *dev)
327 {
328 	int aer = dev->aer_cap;
329 	struct pci_cap_saved_state *save_state;
330 	u32 *cap;
331 
332 	if (!aer)
333 		return;
334 
335 	save_state = pci_find_saved_ext_cap(dev, PCI_EXT_CAP_ID_ERR);
336 	if (!save_state)
337 		return;
338 
339 	cap = &save_state->cap.data[0];
340 	pci_read_config_dword(dev, aer + PCI_ERR_UNCOR_MASK, cap++);
341 	pci_read_config_dword(dev, aer + PCI_ERR_UNCOR_SEVER, cap++);
342 	pci_read_config_dword(dev, aer + PCI_ERR_COR_MASK, cap++);
343 	pci_read_config_dword(dev, aer + PCI_ERR_CAP, cap++);
344 	if (pcie_cap_has_rtctl(dev))
345 		pci_read_config_dword(dev, aer + PCI_ERR_ROOT_COMMAND, cap++);
346 }
347 
348 void pci_restore_aer_state(struct pci_dev *dev)
349 {
350 	int aer = dev->aer_cap;
351 	struct pci_cap_saved_state *save_state;
352 	u32 *cap;
353 
354 	if (!aer)
355 		return;
356 
357 	save_state = pci_find_saved_ext_cap(dev, PCI_EXT_CAP_ID_ERR);
358 	if (!save_state)
359 		return;
360 
361 	cap = &save_state->cap.data[0];
362 	pci_write_config_dword(dev, aer + PCI_ERR_UNCOR_MASK, *cap++);
363 	pci_write_config_dword(dev, aer + PCI_ERR_UNCOR_SEVER, *cap++);
364 	pci_write_config_dword(dev, aer + PCI_ERR_COR_MASK, *cap++);
365 	pci_write_config_dword(dev, aer + PCI_ERR_CAP, *cap++);
366 	if (pcie_cap_has_rtctl(dev))
367 		pci_write_config_dword(dev, aer + PCI_ERR_ROOT_COMMAND, *cap++);
368 }
369 
370 void pci_aer_init(struct pci_dev *dev)
371 {
372 	int n;
373 
374 	dev->aer_cap = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ERR);
375 	if (!dev->aer_cap)
376 		return;
377 
378 	dev->aer_stats = kzalloc(sizeof(struct aer_stats), GFP_KERNEL);
379 
380 	/*
381 	 * We save/restore PCI_ERR_UNCOR_MASK, PCI_ERR_UNCOR_SEVER,
382 	 * PCI_ERR_COR_MASK, and PCI_ERR_CAP.  Root and Root Complex Event
383 	 * Collectors also implement PCI_ERR_ROOT_COMMAND (PCIe r5.0, sec
384 	 * 7.8.4).
385 	 */
386 	n = pcie_cap_has_rtctl(dev) ? 5 : 4;
387 	pci_add_ext_cap_save_buffer(dev, PCI_EXT_CAP_ID_ERR, sizeof(u32) * n);
388 
389 	pci_aer_clear_status(dev);
390 }
391 
392 void pci_aer_exit(struct pci_dev *dev)
393 {
394 	kfree(dev->aer_stats);
395 	dev->aer_stats = NULL;
396 }
397 
398 #define AER_AGENT_RECEIVER		0
399 #define AER_AGENT_REQUESTER		1
400 #define AER_AGENT_COMPLETER		2
401 #define AER_AGENT_TRANSMITTER		3
402 
403 #define AER_AGENT_REQUESTER_MASK(t)	((t == AER_CORRECTABLE) ?	\
404 	0 : (PCI_ERR_UNC_COMP_TIME|PCI_ERR_UNC_UNSUP))
405 #define AER_AGENT_COMPLETER_MASK(t)	((t == AER_CORRECTABLE) ?	\
406 	0 : PCI_ERR_UNC_COMP_ABORT)
407 #define AER_AGENT_TRANSMITTER_MASK(t)	((t == AER_CORRECTABLE) ?	\
408 	(PCI_ERR_COR_REP_ROLL|PCI_ERR_COR_REP_TIMER) : 0)
409 
410 #define AER_GET_AGENT(t, e)						\
411 	((e & AER_AGENT_COMPLETER_MASK(t)) ? AER_AGENT_COMPLETER :	\
412 	(e & AER_AGENT_REQUESTER_MASK(t)) ? AER_AGENT_REQUESTER :	\
413 	(e & AER_AGENT_TRANSMITTER_MASK(t)) ? AER_AGENT_TRANSMITTER :	\
414 	AER_AGENT_RECEIVER)
415 
416 #define AER_PHYSICAL_LAYER_ERROR	0
417 #define AER_DATA_LINK_LAYER_ERROR	1
418 #define AER_TRANSACTION_LAYER_ERROR	2
419 
420 #define AER_PHYSICAL_LAYER_ERROR_MASK(t) ((t == AER_CORRECTABLE) ?	\
421 	PCI_ERR_COR_RCVR : 0)
422 #define AER_DATA_LINK_LAYER_ERROR_MASK(t) ((t == AER_CORRECTABLE) ?	\
423 	(PCI_ERR_COR_BAD_TLP|						\
424 	PCI_ERR_COR_BAD_DLLP|						\
425 	PCI_ERR_COR_REP_ROLL|						\
426 	PCI_ERR_COR_REP_TIMER) : PCI_ERR_UNC_DLP)
427 
428 #define AER_GET_LAYER_ERROR(t, e)					\
429 	((e & AER_PHYSICAL_LAYER_ERROR_MASK(t)) ? AER_PHYSICAL_LAYER_ERROR : \
430 	(e & AER_DATA_LINK_LAYER_ERROR_MASK(t)) ? AER_DATA_LINK_LAYER_ERROR : \
431 	AER_TRANSACTION_LAYER_ERROR)
432 
433 /*
434  * AER error strings
435  */
436 static const char *aer_error_severity_string[] = {
437 	"Uncorrected (Non-Fatal)",
438 	"Uncorrected (Fatal)",
439 	"Corrected"
440 };
441 
442 static const char *aer_error_layer[] = {
443 	"Physical Layer",
444 	"Data Link Layer",
445 	"Transaction Layer"
446 };
447 
448 static const char *aer_correctable_error_string[] = {
449 	"RxErr",			/* Bit Position 0	*/
450 	NULL,
451 	NULL,
452 	NULL,
453 	NULL,
454 	NULL,
455 	"BadTLP",			/* Bit Position 6	*/
456 	"BadDLLP",			/* Bit Position 7	*/
457 	"Rollover",			/* Bit Position 8	*/
458 	NULL,
459 	NULL,
460 	NULL,
461 	"Timeout",			/* Bit Position 12	*/
462 	"NonFatalErr",			/* Bit Position 13	*/
463 	"CorrIntErr",			/* Bit Position 14	*/
464 	"HeaderOF",			/* Bit Position 15	*/
465 	NULL,				/* Bit Position 16	*/
466 	NULL,				/* Bit Position 17	*/
467 	NULL,				/* Bit Position 18	*/
468 	NULL,				/* Bit Position 19	*/
469 	NULL,				/* Bit Position 20	*/
470 	NULL,				/* Bit Position 21	*/
471 	NULL,				/* Bit Position 22	*/
472 	NULL,				/* Bit Position 23	*/
473 	NULL,				/* Bit Position 24	*/
474 	NULL,				/* Bit Position 25	*/
475 	NULL,				/* Bit Position 26	*/
476 	NULL,				/* Bit Position 27	*/
477 	NULL,				/* Bit Position 28	*/
478 	NULL,				/* Bit Position 29	*/
479 	NULL,				/* Bit Position 30	*/
480 	NULL,				/* Bit Position 31	*/
481 };
482 
483 static const char *aer_uncorrectable_error_string[] = {
484 	"Undefined",			/* Bit Position 0	*/
485 	NULL,
486 	NULL,
487 	NULL,
488 	"DLP",				/* Bit Position 4	*/
489 	"SDES",				/* Bit Position 5	*/
490 	NULL,
491 	NULL,
492 	NULL,
493 	NULL,
494 	NULL,
495 	NULL,
496 	"TLP",				/* Bit Position 12	*/
497 	"FCP",				/* Bit Position 13	*/
498 	"CmpltTO",			/* Bit Position 14	*/
499 	"CmpltAbrt",			/* Bit Position 15	*/
500 	"UnxCmplt",			/* Bit Position 16	*/
501 	"RxOF",				/* Bit Position 17	*/
502 	"MalfTLP",			/* Bit Position 18	*/
503 	"ECRC",				/* Bit Position 19	*/
504 	"UnsupReq",			/* Bit Position 20	*/
505 	"ACSViol",			/* Bit Position 21	*/
506 	"UncorrIntErr",			/* Bit Position 22	*/
507 	"BlockedTLP",			/* Bit Position 23	*/
508 	"AtomicOpBlocked",		/* Bit Position 24	*/
509 	"TLPBlockedErr",		/* Bit Position 25	*/
510 	"PoisonTLPBlocked",		/* Bit Position 26	*/
511 	NULL,				/* Bit Position 27	*/
512 	NULL,				/* Bit Position 28	*/
513 	NULL,				/* Bit Position 29	*/
514 	NULL,				/* Bit Position 30	*/
515 	NULL,				/* Bit Position 31	*/
516 };
517 
518 static const char *aer_agent_string[] = {
519 	"Receiver ID",
520 	"Requester ID",
521 	"Completer ID",
522 	"Transmitter ID"
523 };
524 
525 #define aer_stats_dev_attr(name, stats_array, strings_array,		\
526 			   total_string, total_field)			\
527 	static ssize_t							\
528 	name##_show(struct device *dev, struct device_attribute *attr,	\
529 		     char *buf)						\
530 {									\
531 	unsigned int i;							\
532 	struct pci_dev *pdev = to_pci_dev(dev);				\
533 	u64 *stats = pdev->aer_stats->stats_array;			\
534 	size_t len = 0;							\
535 									\
536 	for (i = 0; i < ARRAY_SIZE(strings_array); i++) {		\
537 		if (strings_array[i])					\
538 			len += sysfs_emit_at(buf, len, "%s %llu\n",	\
539 					     strings_array[i],		\
540 					     stats[i]);			\
541 		else if (stats[i])					\
542 			len += sysfs_emit_at(buf, len,			\
543 					     #stats_array "_bit[%d] %llu\n",\
544 					     i, stats[i]);		\
545 	}								\
546 	len += sysfs_emit_at(buf, len, "TOTAL_%s %llu\n", total_string,	\
547 			     pdev->aer_stats->total_field);		\
548 	return len;							\
549 }									\
550 static DEVICE_ATTR_RO(name)
551 
552 aer_stats_dev_attr(aer_dev_correctable, dev_cor_errs,
553 		   aer_correctable_error_string, "ERR_COR",
554 		   dev_total_cor_errs);
555 aer_stats_dev_attr(aer_dev_fatal, dev_fatal_errs,
556 		   aer_uncorrectable_error_string, "ERR_FATAL",
557 		   dev_total_fatal_errs);
558 aer_stats_dev_attr(aer_dev_nonfatal, dev_nonfatal_errs,
559 		   aer_uncorrectable_error_string, "ERR_NONFATAL",
560 		   dev_total_nonfatal_errs);
561 
562 #define aer_stats_rootport_attr(name, field)				\
563 	static ssize_t							\
564 	name##_show(struct device *dev, struct device_attribute *attr,	\
565 		     char *buf)						\
566 {									\
567 	struct pci_dev *pdev = to_pci_dev(dev);				\
568 	return sysfs_emit(buf, "%llu\n", pdev->aer_stats->field);	\
569 }									\
570 static DEVICE_ATTR_RO(name)
571 
572 aer_stats_rootport_attr(aer_rootport_total_err_cor,
573 			 rootport_total_cor_errs);
574 aer_stats_rootport_attr(aer_rootport_total_err_fatal,
575 			 rootport_total_fatal_errs);
576 aer_stats_rootport_attr(aer_rootport_total_err_nonfatal,
577 			 rootport_total_nonfatal_errs);
578 
579 static struct attribute *aer_stats_attrs[] __ro_after_init = {
580 	&dev_attr_aer_dev_correctable.attr,
581 	&dev_attr_aer_dev_fatal.attr,
582 	&dev_attr_aer_dev_nonfatal.attr,
583 	&dev_attr_aer_rootport_total_err_cor.attr,
584 	&dev_attr_aer_rootport_total_err_fatal.attr,
585 	&dev_attr_aer_rootport_total_err_nonfatal.attr,
586 	NULL
587 };
588 
589 static umode_t aer_stats_attrs_are_visible(struct kobject *kobj,
590 					   struct attribute *a, int n)
591 {
592 	struct device *dev = kobj_to_dev(kobj);
593 	struct pci_dev *pdev = to_pci_dev(dev);
594 
595 	if (!pdev->aer_stats)
596 		return 0;
597 
598 	if ((a == &dev_attr_aer_rootport_total_err_cor.attr ||
599 	     a == &dev_attr_aer_rootport_total_err_fatal.attr ||
600 	     a == &dev_attr_aer_rootport_total_err_nonfatal.attr) &&
601 	    ((pci_pcie_type(pdev) != PCI_EXP_TYPE_ROOT_PORT) &&
602 	     (pci_pcie_type(pdev) != PCI_EXP_TYPE_RC_EC)))
603 		return 0;
604 
605 	return a->mode;
606 }
607 
608 const struct attribute_group aer_stats_attr_group = {
609 	.attrs  = aer_stats_attrs,
610 	.is_visible = aer_stats_attrs_are_visible,
611 };
612 
613 static void pci_dev_aer_stats_incr(struct pci_dev *pdev,
614 				   struct aer_err_info *info)
615 {
616 	unsigned long status = info->status & ~info->mask;
617 	int i, max = -1;
618 	u64 *counter = NULL;
619 	struct aer_stats *aer_stats = pdev->aer_stats;
620 
621 	if (!aer_stats)
622 		return;
623 
624 	switch (info->severity) {
625 	case AER_CORRECTABLE:
626 		aer_stats->dev_total_cor_errs++;
627 		counter = &aer_stats->dev_cor_errs[0];
628 		max = AER_MAX_TYPEOF_COR_ERRS;
629 		break;
630 	case AER_NONFATAL:
631 		aer_stats->dev_total_nonfatal_errs++;
632 		counter = &aer_stats->dev_nonfatal_errs[0];
633 		max = AER_MAX_TYPEOF_UNCOR_ERRS;
634 		break;
635 	case AER_FATAL:
636 		aer_stats->dev_total_fatal_errs++;
637 		counter = &aer_stats->dev_fatal_errs[0];
638 		max = AER_MAX_TYPEOF_UNCOR_ERRS;
639 		break;
640 	}
641 
642 	for_each_set_bit(i, &status, max)
643 		counter[i]++;
644 }
645 
646 static void pci_rootport_aer_stats_incr(struct pci_dev *pdev,
647 				 struct aer_err_source *e_src)
648 {
649 	struct aer_stats *aer_stats = pdev->aer_stats;
650 
651 	if (!aer_stats)
652 		return;
653 
654 	if (e_src->status & PCI_ERR_ROOT_COR_RCV)
655 		aer_stats->rootport_total_cor_errs++;
656 
657 	if (e_src->status & PCI_ERR_ROOT_UNCOR_RCV) {
658 		if (e_src->status & PCI_ERR_ROOT_FATAL_RCV)
659 			aer_stats->rootport_total_fatal_errs++;
660 		else
661 			aer_stats->rootport_total_nonfatal_errs++;
662 	}
663 }
664 
665 static void __print_tlp_header(struct pci_dev *dev,
666 			       struct aer_header_log_regs *t)
667 {
668 	pci_err(dev, "  TLP Header: %08x %08x %08x %08x\n",
669 		t->dw0, t->dw1, t->dw2, t->dw3);
670 }
671 
672 static void __aer_print_error(struct pci_dev *dev,
673 			      struct aer_err_info *info)
674 {
675 	const char **strings;
676 	unsigned long status = info->status & ~info->mask;
677 	const char *level, *errmsg;
678 	int i;
679 
680 	if (info->severity == AER_CORRECTABLE) {
681 		strings = aer_correctable_error_string;
682 		level = KERN_WARNING;
683 	} else {
684 		strings = aer_uncorrectable_error_string;
685 		level = KERN_ERR;
686 	}
687 
688 	for_each_set_bit(i, &status, 32) {
689 		errmsg = strings[i];
690 		if (!errmsg)
691 			errmsg = "Unknown Error Bit";
692 
693 		pci_printk(level, dev, "   [%2d] %-22s%s\n", i, errmsg,
694 				info->first_error == i ? " (First)" : "");
695 	}
696 	pci_dev_aer_stats_incr(dev, info);
697 }
698 
699 void aer_print_error(struct pci_dev *dev, struct aer_err_info *info)
700 {
701 	int layer, agent;
702 	int id = ((dev->bus->number << 8) | dev->devfn);
703 	const char *level;
704 
705 	if (!info->status) {
706 		pci_err(dev, "PCIe Bus Error: severity=%s, type=Inaccessible, (Unregistered Agent ID)\n",
707 			aer_error_severity_string[info->severity]);
708 		goto out;
709 	}
710 
711 	layer = AER_GET_LAYER_ERROR(info->severity, info->status);
712 	agent = AER_GET_AGENT(info->severity, info->status);
713 
714 	level = (info->severity == AER_CORRECTABLE) ? KERN_WARNING : KERN_ERR;
715 
716 	pci_printk(level, dev, "PCIe Bus Error: severity=%s, type=%s, (%s)\n",
717 		   aer_error_severity_string[info->severity],
718 		   aer_error_layer[layer], aer_agent_string[agent]);
719 
720 	pci_printk(level, dev, "  device [%04x:%04x] error status/mask=%08x/%08x\n",
721 		   dev->vendor, dev->device, info->status, info->mask);
722 
723 	__aer_print_error(dev, info);
724 
725 	if (info->tlp_header_valid)
726 		__print_tlp_header(dev, &info->tlp);
727 
728 out:
729 	if (info->id && info->error_dev_num > 1 && info->id == id)
730 		pci_err(dev, "  Error of this Agent is reported first\n");
731 
732 	trace_aer_event(dev_name(&dev->dev), (info->status & ~info->mask),
733 			info->severity, info->tlp_header_valid, &info->tlp);
734 }
735 
736 static void aer_print_port_info(struct pci_dev *dev, struct aer_err_info *info)
737 {
738 	u8 bus = info->id >> 8;
739 	u8 devfn = info->id & 0xff;
740 
741 	pci_info(dev, "%s%s error received: %04x:%02x:%02x.%d\n",
742 		 info->multi_error_valid ? "Multiple " : "",
743 		 aer_error_severity_string[info->severity],
744 		 pci_domain_nr(dev->bus), bus, PCI_SLOT(devfn),
745 		 PCI_FUNC(devfn));
746 }
747 
748 #ifdef CONFIG_ACPI_APEI_PCIEAER
749 int cper_severity_to_aer(int cper_severity)
750 {
751 	switch (cper_severity) {
752 	case CPER_SEV_RECOVERABLE:
753 		return AER_NONFATAL;
754 	case CPER_SEV_FATAL:
755 		return AER_FATAL;
756 	default:
757 		return AER_CORRECTABLE;
758 	}
759 }
760 EXPORT_SYMBOL_GPL(cper_severity_to_aer);
761 
762 void cper_print_aer(struct pci_dev *dev, int aer_severity,
763 		    struct aer_capability_regs *aer)
764 {
765 	int layer, agent, tlp_header_valid = 0;
766 	u32 status, mask;
767 	struct aer_err_info info;
768 
769 	if (aer_severity == AER_CORRECTABLE) {
770 		status = aer->cor_status;
771 		mask = aer->cor_mask;
772 	} else {
773 		status = aer->uncor_status;
774 		mask = aer->uncor_mask;
775 		tlp_header_valid = status & AER_LOG_TLP_MASKS;
776 	}
777 
778 	layer = AER_GET_LAYER_ERROR(aer_severity, status);
779 	agent = AER_GET_AGENT(aer_severity, status);
780 
781 	memset(&info, 0, sizeof(info));
782 	info.severity = aer_severity;
783 	info.status = status;
784 	info.mask = mask;
785 	info.first_error = PCI_ERR_CAP_FEP(aer->cap_control);
786 
787 	pci_err(dev, "aer_status: 0x%08x, aer_mask: 0x%08x\n", status, mask);
788 	__aer_print_error(dev, &info);
789 	pci_err(dev, "aer_layer=%s, aer_agent=%s\n",
790 		aer_error_layer[layer], aer_agent_string[agent]);
791 
792 	if (aer_severity != AER_CORRECTABLE)
793 		pci_err(dev, "aer_uncor_severity: 0x%08x\n",
794 			aer->uncor_severity);
795 
796 	if (tlp_header_valid)
797 		__print_tlp_header(dev, &aer->header_log);
798 
799 	trace_aer_event(dev_name(&dev->dev), (status & ~mask),
800 			aer_severity, tlp_header_valid, &aer->header_log);
801 }
802 #endif
803 
804 /**
805  * add_error_device - list device to be handled
806  * @e_info: pointer to error info
807  * @dev: pointer to pci_dev to be added
808  */
809 static int add_error_device(struct aer_err_info *e_info, struct pci_dev *dev)
810 {
811 	if (e_info->error_dev_num < AER_MAX_MULTI_ERR_DEVICES) {
812 		e_info->dev[e_info->error_dev_num] = pci_dev_get(dev);
813 		e_info->error_dev_num++;
814 		return 0;
815 	}
816 	return -ENOSPC;
817 }
818 
819 /**
820  * is_error_source - check whether the device is source of reported error
821  * @dev: pointer to pci_dev to be checked
822  * @e_info: pointer to reported error info
823  */
824 static bool is_error_source(struct pci_dev *dev, struct aer_err_info *e_info)
825 {
826 	int aer = dev->aer_cap;
827 	u32 status, mask;
828 	u16 reg16;
829 
830 	/*
831 	 * When bus id is equal to 0, it might be a bad id
832 	 * reported by root port.
833 	 */
834 	if ((PCI_BUS_NUM(e_info->id) != 0) &&
835 	    !(dev->bus->bus_flags & PCI_BUS_FLAGS_NO_AERSID)) {
836 		/* Device ID match? */
837 		if (e_info->id == ((dev->bus->number << 8) | dev->devfn))
838 			return true;
839 
840 		/* Continue id comparing if there is no multiple error */
841 		if (!e_info->multi_error_valid)
842 			return false;
843 	}
844 
845 	/*
846 	 * When either
847 	 *      1) bus id is equal to 0. Some ports might lose the bus
848 	 *              id of error source id;
849 	 *      2) bus flag PCI_BUS_FLAGS_NO_AERSID is set
850 	 *      3) There are multiple errors and prior ID comparing fails;
851 	 * We check AER status registers to find possible reporter.
852 	 */
853 	if (atomic_read(&dev->enable_cnt) == 0)
854 		return false;
855 
856 	/* Check if AER is enabled */
857 	pcie_capability_read_word(dev, PCI_EXP_DEVCTL, &reg16);
858 	if (!(reg16 & PCI_EXP_AER_FLAGS))
859 		return false;
860 
861 	if (!aer)
862 		return false;
863 
864 	/* Check if error is recorded */
865 	if (e_info->severity == AER_CORRECTABLE) {
866 		pci_read_config_dword(dev, aer + PCI_ERR_COR_STATUS, &status);
867 		pci_read_config_dword(dev, aer + PCI_ERR_COR_MASK, &mask);
868 	} else {
869 		pci_read_config_dword(dev, aer + PCI_ERR_UNCOR_STATUS, &status);
870 		pci_read_config_dword(dev, aer + PCI_ERR_UNCOR_MASK, &mask);
871 	}
872 	if (status & ~mask)
873 		return true;
874 
875 	return false;
876 }
877 
878 static int find_device_iter(struct pci_dev *dev, void *data)
879 {
880 	struct aer_err_info *e_info = (struct aer_err_info *)data;
881 
882 	if (is_error_source(dev, e_info)) {
883 		/* List this device */
884 		if (add_error_device(e_info, dev)) {
885 			/* We cannot handle more... Stop iteration */
886 			/* TODO: Should print error message here? */
887 			return 1;
888 		}
889 
890 		/* If there is only a single error, stop iteration */
891 		if (!e_info->multi_error_valid)
892 			return 1;
893 	}
894 	return 0;
895 }
896 
897 /**
898  * find_source_device - search through device hierarchy for source device
899  * @parent: pointer to Root Port pci_dev data structure
900  * @e_info: including detailed error information such like id
901  *
902  * Return true if found.
903  *
904  * Invoked by DPC when error is detected at the Root Port.
905  * Caller of this function must set id, severity, and multi_error_valid of
906  * struct aer_err_info pointed by @e_info properly.  This function must fill
907  * e_info->error_dev_num and e_info->dev[], based on the given information.
908  */
909 static bool find_source_device(struct pci_dev *parent,
910 		struct aer_err_info *e_info)
911 {
912 	struct pci_dev *dev = parent;
913 	int result;
914 
915 	/* Must reset in this function */
916 	e_info->error_dev_num = 0;
917 
918 	/* Is Root Port an agent that sends error message? */
919 	result = find_device_iter(dev, e_info);
920 	if (result)
921 		return true;
922 
923 	if (pci_pcie_type(parent) == PCI_EXP_TYPE_RC_EC)
924 		pcie_walk_rcec(parent, find_device_iter, e_info);
925 	else
926 		pci_walk_bus(parent->subordinate, find_device_iter, e_info);
927 
928 	if (!e_info->error_dev_num) {
929 		pci_info(parent, "can't find device of ID%04x\n", e_info->id);
930 		return false;
931 	}
932 	return true;
933 }
934 
935 /**
936  * handle_error_source - handle logging error into an event log
937  * @dev: pointer to pci_dev data structure of error source device
938  * @info: comprehensive error information
939  *
940  * Invoked when an error being detected by Root Port.
941  */
942 static void handle_error_source(struct pci_dev *dev, struct aer_err_info *info)
943 {
944 	int aer = dev->aer_cap;
945 
946 	if (info->severity == AER_CORRECTABLE) {
947 		/*
948 		 * Correctable error does not need software intervention.
949 		 * No need to go through error recovery process.
950 		 */
951 		if (aer)
952 			pci_write_config_dword(dev, aer + PCI_ERR_COR_STATUS,
953 					info->status);
954 		if (pcie_aer_is_native(dev))
955 			pcie_clear_device_status(dev);
956 	} else if (info->severity == AER_NONFATAL)
957 		pcie_do_recovery(dev, pci_channel_io_normal, aer_root_reset);
958 	else if (info->severity == AER_FATAL)
959 		pcie_do_recovery(dev, pci_channel_io_frozen, aer_root_reset);
960 	pci_dev_put(dev);
961 }
962 
963 #ifdef CONFIG_ACPI_APEI_PCIEAER
964 
965 #define AER_RECOVER_RING_ORDER		4
966 #define AER_RECOVER_RING_SIZE		(1 << AER_RECOVER_RING_ORDER)
967 
968 struct aer_recover_entry {
969 	u8	bus;
970 	u8	devfn;
971 	u16	domain;
972 	int	severity;
973 	struct aer_capability_regs *regs;
974 };
975 
976 static DEFINE_KFIFO(aer_recover_ring, struct aer_recover_entry,
977 		    AER_RECOVER_RING_SIZE);
978 
979 static void aer_recover_work_func(struct work_struct *work)
980 {
981 	struct aer_recover_entry entry;
982 	struct pci_dev *pdev;
983 
984 	while (kfifo_get(&aer_recover_ring, &entry)) {
985 		pdev = pci_get_domain_bus_and_slot(entry.domain, entry.bus,
986 						   entry.devfn);
987 		if (!pdev) {
988 			pr_err("no pci_dev for %04x:%02x:%02x.%x\n",
989 			       entry.domain, entry.bus,
990 			       PCI_SLOT(entry.devfn), PCI_FUNC(entry.devfn));
991 			continue;
992 		}
993 		cper_print_aer(pdev, entry.severity, entry.regs);
994 		if (entry.severity == AER_NONFATAL)
995 			pcie_do_recovery(pdev, pci_channel_io_normal,
996 					 aer_root_reset);
997 		else if (entry.severity == AER_FATAL)
998 			pcie_do_recovery(pdev, pci_channel_io_frozen,
999 					 aer_root_reset);
1000 		pci_dev_put(pdev);
1001 	}
1002 }
1003 
1004 /*
1005  * Mutual exclusion for writers of aer_recover_ring, reader side don't
1006  * need lock, because there is only one reader and lock is not needed
1007  * between reader and writer.
1008  */
1009 static DEFINE_SPINLOCK(aer_recover_ring_lock);
1010 static DECLARE_WORK(aer_recover_work, aer_recover_work_func);
1011 
1012 void aer_recover_queue(int domain, unsigned int bus, unsigned int devfn,
1013 		       int severity, struct aer_capability_regs *aer_regs)
1014 {
1015 	struct aer_recover_entry entry = {
1016 		.bus		= bus,
1017 		.devfn		= devfn,
1018 		.domain		= domain,
1019 		.severity	= severity,
1020 		.regs		= aer_regs,
1021 	};
1022 
1023 	if (kfifo_in_spinlocked(&aer_recover_ring, &entry, 1,
1024 				 &aer_recover_ring_lock))
1025 		schedule_work(&aer_recover_work);
1026 	else
1027 		pr_err("buffer overflow in recovery for %04x:%02x:%02x.%x\n",
1028 		       domain, bus, PCI_SLOT(devfn), PCI_FUNC(devfn));
1029 }
1030 EXPORT_SYMBOL_GPL(aer_recover_queue);
1031 #endif
1032 
1033 /**
1034  * aer_get_device_error_info - read error status from dev and store it to info
1035  * @dev: pointer to the device expected to have a error record
1036  * @info: pointer to structure to store the error record
1037  *
1038  * Return 1 on success, 0 on error.
1039  *
1040  * Note that @info is reused among all error devices. Clear fields properly.
1041  */
1042 int aer_get_device_error_info(struct pci_dev *dev, struct aer_err_info *info)
1043 {
1044 	int type = pci_pcie_type(dev);
1045 	int aer = dev->aer_cap;
1046 	int temp;
1047 
1048 	/* Must reset in this function */
1049 	info->status = 0;
1050 	info->tlp_header_valid = 0;
1051 
1052 	/* The device might not support AER */
1053 	if (!aer)
1054 		return 0;
1055 
1056 	if (info->severity == AER_CORRECTABLE) {
1057 		pci_read_config_dword(dev, aer + PCI_ERR_COR_STATUS,
1058 			&info->status);
1059 		pci_read_config_dword(dev, aer + PCI_ERR_COR_MASK,
1060 			&info->mask);
1061 		if (!(info->status & ~info->mask))
1062 			return 0;
1063 	} else if (type == PCI_EXP_TYPE_ROOT_PORT ||
1064 		   type == PCI_EXP_TYPE_RC_EC ||
1065 		   type == PCI_EXP_TYPE_DOWNSTREAM ||
1066 		   info->severity == AER_NONFATAL) {
1067 
1068 		/* Link is still healthy for IO reads */
1069 		pci_read_config_dword(dev, aer + PCI_ERR_UNCOR_STATUS,
1070 			&info->status);
1071 		pci_read_config_dword(dev, aer + PCI_ERR_UNCOR_MASK,
1072 			&info->mask);
1073 		if (!(info->status & ~info->mask))
1074 			return 0;
1075 
1076 		/* Get First Error Pointer */
1077 		pci_read_config_dword(dev, aer + PCI_ERR_CAP, &temp);
1078 		info->first_error = PCI_ERR_CAP_FEP(temp);
1079 
1080 		if (info->status & AER_LOG_TLP_MASKS) {
1081 			info->tlp_header_valid = 1;
1082 			pci_read_config_dword(dev,
1083 				aer + PCI_ERR_HEADER_LOG, &info->tlp.dw0);
1084 			pci_read_config_dword(dev,
1085 				aer + PCI_ERR_HEADER_LOG + 4, &info->tlp.dw1);
1086 			pci_read_config_dword(dev,
1087 				aer + PCI_ERR_HEADER_LOG + 8, &info->tlp.dw2);
1088 			pci_read_config_dword(dev,
1089 				aer + PCI_ERR_HEADER_LOG + 12, &info->tlp.dw3);
1090 		}
1091 	}
1092 
1093 	return 1;
1094 }
1095 
1096 static inline void aer_process_err_devices(struct aer_err_info *e_info)
1097 {
1098 	int i;
1099 
1100 	/* Report all before handle them, not to lost records by reset etc. */
1101 	for (i = 0; i < e_info->error_dev_num && e_info->dev[i]; i++) {
1102 		if (aer_get_device_error_info(e_info->dev[i], e_info))
1103 			aer_print_error(e_info->dev[i], e_info);
1104 	}
1105 	for (i = 0; i < e_info->error_dev_num && e_info->dev[i]; i++) {
1106 		if (aer_get_device_error_info(e_info->dev[i], e_info))
1107 			handle_error_source(e_info->dev[i], e_info);
1108 	}
1109 }
1110 
1111 /**
1112  * aer_isr_one_error - consume an error detected by root port
1113  * @rpc: pointer to the root port which holds an error
1114  * @e_src: pointer to an error source
1115  */
1116 static void aer_isr_one_error(struct aer_rpc *rpc,
1117 		struct aer_err_source *e_src)
1118 {
1119 	struct pci_dev *pdev = rpc->rpd;
1120 	struct aer_err_info e_info;
1121 
1122 	pci_rootport_aer_stats_incr(pdev, e_src);
1123 
1124 	/*
1125 	 * There is a possibility that both correctable error and
1126 	 * uncorrectable error being logged. Report correctable error first.
1127 	 */
1128 	if (e_src->status & PCI_ERR_ROOT_COR_RCV) {
1129 		e_info.id = ERR_COR_ID(e_src->id);
1130 		e_info.severity = AER_CORRECTABLE;
1131 
1132 		if (e_src->status & PCI_ERR_ROOT_MULTI_COR_RCV)
1133 			e_info.multi_error_valid = 1;
1134 		else
1135 			e_info.multi_error_valid = 0;
1136 		aer_print_port_info(pdev, &e_info);
1137 
1138 		if (find_source_device(pdev, &e_info))
1139 			aer_process_err_devices(&e_info);
1140 	}
1141 
1142 	if (e_src->status & PCI_ERR_ROOT_UNCOR_RCV) {
1143 		e_info.id = ERR_UNCOR_ID(e_src->id);
1144 
1145 		if (e_src->status & PCI_ERR_ROOT_FATAL_RCV)
1146 			e_info.severity = AER_FATAL;
1147 		else
1148 			e_info.severity = AER_NONFATAL;
1149 
1150 		if (e_src->status & PCI_ERR_ROOT_MULTI_UNCOR_RCV)
1151 			e_info.multi_error_valid = 1;
1152 		else
1153 			e_info.multi_error_valid = 0;
1154 
1155 		aer_print_port_info(pdev, &e_info);
1156 
1157 		if (find_source_device(pdev, &e_info))
1158 			aer_process_err_devices(&e_info);
1159 	}
1160 }
1161 
1162 /**
1163  * aer_isr - consume errors detected by root port
1164  * @irq: IRQ assigned to Root Port
1165  * @context: pointer to Root Port data structure
1166  *
1167  * Invoked, as DPC, when root port records new detected error
1168  */
1169 static irqreturn_t aer_isr(int irq, void *context)
1170 {
1171 	struct pcie_device *dev = (struct pcie_device *)context;
1172 	struct aer_rpc *rpc = get_service_data(dev);
1173 	struct aer_err_source e_src;
1174 
1175 	if (kfifo_is_empty(&rpc->aer_fifo))
1176 		return IRQ_NONE;
1177 
1178 	while (kfifo_get(&rpc->aer_fifo, &e_src))
1179 		aer_isr_one_error(rpc, &e_src);
1180 	return IRQ_HANDLED;
1181 }
1182 
1183 /**
1184  * aer_irq - Root Port's ISR
1185  * @irq: IRQ assigned to Root Port
1186  * @context: pointer to Root Port data structure
1187  *
1188  * Invoked when Root Port detects AER messages.
1189  */
1190 static irqreturn_t aer_irq(int irq, void *context)
1191 {
1192 	struct pcie_device *pdev = (struct pcie_device *)context;
1193 	struct aer_rpc *rpc = get_service_data(pdev);
1194 	struct pci_dev *rp = rpc->rpd;
1195 	int aer = rp->aer_cap;
1196 	struct aer_err_source e_src = {};
1197 
1198 	pci_read_config_dword(rp, aer + PCI_ERR_ROOT_STATUS, &e_src.status);
1199 	if (!(e_src.status & (PCI_ERR_ROOT_UNCOR_RCV|PCI_ERR_ROOT_COR_RCV)))
1200 		return IRQ_NONE;
1201 
1202 	pci_read_config_dword(rp, aer + PCI_ERR_ROOT_ERR_SRC, &e_src.id);
1203 	pci_write_config_dword(rp, aer + PCI_ERR_ROOT_STATUS, e_src.status);
1204 
1205 	if (!kfifo_put(&rpc->aer_fifo, e_src))
1206 		return IRQ_HANDLED;
1207 
1208 	return IRQ_WAKE_THREAD;
1209 }
1210 
1211 static int set_device_error_reporting(struct pci_dev *dev, void *data)
1212 {
1213 	bool enable = *((bool *)data);
1214 	int type = pci_pcie_type(dev);
1215 
1216 	if ((type == PCI_EXP_TYPE_ROOT_PORT) ||
1217 	    (type == PCI_EXP_TYPE_RC_EC) ||
1218 	    (type == PCI_EXP_TYPE_UPSTREAM) ||
1219 	    (type == PCI_EXP_TYPE_DOWNSTREAM)) {
1220 		if (enable)
1221 			pci_enable_pcie_error_reporting(dev);
1222 		else
1223 			pci_disable_pcie_error_reporting(dev);
1224 	}
1225 
1226 	if (enable)
1227 		pcie_set_ecrc_checking(dev);
1228 
1229 	return 0;
1230 }
1231 
1232 /**
1233  * set_downstream_devices_error_reporting - enable/disable the error reporting  bits on the root port and its downstream ports.
1234  * @dev: pointer to root port's pci_dev data structure
1235  * @enable: true = enable error reporting, false = disable error reporting.
1236  */
1237 static void set_downstream_devices_error_reporting(struct pci_dev *dev,
1238 						   bool enable)
1239 {
1240 	set_device_error_reporting(dev, &enable);
1241 
1242 	if (pci_pcie_type(dev) == PCI_EXP_TYPE_RC_EC)
1243 		pcie_walk_rcec(dev, set_device_error_reporting, &enable);
1244 	else if (dev->subordinate)
1245 		pci_walk_bus(dev->subordinate, set_device_error_reporting,
1246 			     &enable);
1247 
1248 }
1249 
1250 /**
1251  * aer_enable_rootport - enable Root Port's interrupts when receiving messages
1252  * @rpc: pointer to a Root Port data structure
1253  *
1254  * Invoked when PCIe bus loads AER service driver.
1255  */
1256 static void aer_enable_rootport(struct aer_rpc *rpc)
1257 {
1258 	struct pci_dev *pdev = rpc->rpd;
1259 	int aer = pdev->aer_cap;
1260 	u16 reg16;
1261 	u32 reg32;
1262 
1263 	/* Clear PCIe Capability's Device Status */
1264 	pcie_capability_read_word(pdev, PCI_EXP_DEVSTA, &reg16);
1265 	pcie_capability_write_word(pdev, PCI_EXP_DEVSTA, reg16);
1266 
1267 	/* Disable system error generation in response to error messages */
1268 	pcie_capability_clear_word(pdev, PCI_EXP_RTCTL,
1269 				   SYSTEM_ERROR_INTR_ON_MESG_MASK);
1270 
1271 	/* Clear error status */
1272 	pci_read_config_dword(pdev, aer + PCI_ERR_ROOT_STATUS, &reg32);
1273 	pci_write_config_dword(pdev, aer + PCI_ERR_ROOT_STATUS, reg32);
1274 	pci_read_config_dword(pdev, aer + PCI_ERR_COR_STATUS, &reg32);
1275 	pci_write_config_dword(pdev, aer + PCI_ERR_COR_STATUS, reg32);
1276 	pci_read_config_dword(pdev, aer + PCI_ERR_UNCOR_STATUS, &reg32);
1277 	pci_write_config_dword(pdev, aer + PCI_ERR_UNCOR_STATUS, reg32);
1278 
1279 	/*
1280 	 * Enable error reporting for the root port device and downstream port
1281 	 * devices.
1282 	 */
1283 	set_downstream_devices_error_reporting(pdev, true);
1284 
1285 	/* Enable Root Port's interrupt in response to error messages */
1286 	pci_read_config_dword(pdev, aer + PCI_ERR_ROOT_COMMAND, &reg32);
1287 	reg32 |= ROOT_PORT_INTR_ON_MESG_MASK;
1288 	pci_write_config_dword(pdev, aer + PCI_ERR_ROOT_COMMAND, reg32);
1289 }
1290 
1291 /**
1292  * aer_disable_rootport - disable Root Port's interrupts when receiving messages
1293  * @rpc: pointer to a Root Port data structure
1294  *
1295  * Invoked when PCIe bus unloads AER service driver.
1296  */
1297 static void aer_disable_rootport(struct aer_rpc *rpc)
1298 {
1299 	struct pci_dev *pdev = rpc->rpd;
1300 	int aer = pdev->aer_cap;
1301 	u32 reg32;
1302 
1303 	/*
1304 	 * Disable error reporting for the root port device and downstream port
1305 	 * devices.
1306 	 */
1307 	set_downstream_devices_error_reporting(pdev, false);
1308 
1309 	/* Disable Root's interrupt in response to error messages */
1310 	pci_read_config_dword(pdev, aer + PCI_ERR_ROOT_COMMAND, &reg32);
1311 	reg32 &= ~ROOT_PORT_INTR_ON_MESG_MASK;
1312 	pci_write_config_dword(pdev, aer + PCI_ERR_ROOT_COMMAND, reg32);
1313 
1314 	/* Clear Root's error status reg */
1315 	pci_read_config_dword(pdev, aer + PCI_ERR_ROOT_STATUS, &reg32);
1316 	pci_write_config_dword(pdev, aer + PCI_ERR_ROOT_STATUS, reg32);
1317 }
1318 
1319 /**
1320  * aer_remove - clean up resources
1321  * @dev: pointer to the pcie_dev data structure
1322  *
1323  * Invoked when PCI Express bus unloads or AER probe fails.
1324  */
1325 static void aer_remove(struct pcie_device *dev)
1326 {
1327 	struct aer_rpc *rpc = get_service_data(dev);
1328 
1329 	aer_disable_rootport(rpc);
1330 }
1331 
1332 /**
1333  * aer_probe - initialize resources
1334  * @dev: pointer to the pcie_dev data structure
1335  *
1336  * Invoked when PCI Express bus loads AER service driver.
1337  */
1338 static int aer_probe(struct pcie_device *dev)
1339 {
1340 	int status;
1341 	struct aer_rpc *rpc;
1342 	struct device *device = &dev->device;
1343 	struct pci_dev *port = dev->port;
1344 
1345 	/* Limit to Root Ports or Root Complex Event Collectors */
1346 	if ((pci_pcie_type(port) != PCI_EXP_TYPE_RC_EC) &&
1347 	    (pci_pcie_type(port) != PCI_EXP_TYPE_ROOT_PORT))
1348 		return -ENODEV;
1349 
1350 	rpc = devm_kzalloc(device, sizeof(struct aer_rpc), GFP_KERNEL);
1351 	if (!rpc)
1352 		return -ENOMEM;
1353 
1354 	rpc->rpd = port;
1355 	INIT_KFIFO(rpc->aer_fifo);
1356 	set_service_data(dev, rpc);
1357 
1358 	status = devm_request_threaded_irq(device, dev->irq, aer_irq, aer_isr,
1359 					   IRQF_SHARED, "aerdrv", dev);
1360 	if (status) {
1361 		pci_err(port, "request AER IRQ %d failed\n", dev->irq);
1362 		return status;
1363 	}
1364 
1365 	aer_enable_rootport(rpc);
1366 	pci_info(port, "enabled with IRQ %d\n", dev->irq);
1367 	return 0;
1368 }
1369 
1370 /**
1371  * aer_root_reset - reset Root Port hierarchy, RCEC, or RCiEP
1372  * @dev: pointer to Root Port, RCEC, or RCiEP
1373  *
1374  * Invoked by Port Bus driver when performing reset.
1375  */
1376 static pci_ers_result_t aer_root_reset(struct pci_dev *dev)
1377 {
1378 	int type = pci_pcie_type(dev);
1379 	struct pci_dev *root;
1380 	int aer;
1381 	struct pci_host_bridge *host = pci_find_host_bridge(dev->bus);
1382 	u32 reg32;
1383 	int rc;
1384 
1385 	/*
1386 	 * Only Root Ports and RCECs have AER Root Command and Root Status
1387 	 * registers.  If "dev" is an RCiEP, the relevant registers are in
1388 	 * the RCEC.
1389 	 */
1390 	if (type == PCI_EXP_TYPE_RC_END)
1391 		root = dev->rcec;
1392 	else
1393 		root = pcie_find_root_port(dev);
1394 
1395 	/*
1396 	 * If the platform retained control of AER, an RCiEP may not have
1397 	 * an RCEC visible to us, so dev->rcec ("root") may be NULL.  In
1398 	 * that case, firmware is responsible for these registers.
1399 	 */
1400 	aer = root ? root->aer_cap : 0;
1401 
1402 	if ((host->native_aer || pcie_ports_native) && aer) {
1403 		/* Disable Root's interrupt in response to error messages */
1404 		pci_read_config_dword(root, aer + PCI_ERR_ROOT_COMMAND, &reg32);
1405 		reg32 &= ~ROOT_PORT_INTR_ON_MESG_MASK;
1406 		pci_write_config_dword(root, aer + PCI_ERR_ROOT_COMMAND, reg32);
1407 	}
1408 
1409 	if (type == PCI_EXP_TYPE_RC_EC || type == PCI_EXP_TYPE_RC_END) {
1410 		rc = pcie_reset_flr(dev, PCI_RESET_DO_RESET);
1411 		if (!rc)
1412 			pci_info(dev, "has been reset\n");
1413 		else
1414 			pci_info(dev, "not reset (no FLR support: %d)\n", rc);
1415 	} else {
1416 		rc = pci_bus_error_reset(dev);
1417 		pci_info(dev, "%s Port link has been reset (%d)\n",
1418 			pci_is_root_bus(dev->bus) ? "Root" : "Downstream", rc);
1419 	}
1420 
1421 	if ((host->native_aer || pcie_ports_native) && aer) {
1422 		/* Clear Root Error Status */
1423 		pci_read_config_dword(root, aer + PCI_ERR_ROOT_STATUS, &reg32);
1424 		pci_write_config_dword(root, aer + PCI_ERR_ROOT_STATUS, reg32);
1425 
1426 		/* Enable Root Port's interrupt in response to error messages */
1427 		pci_read_config_dword(root, aer + PCI_ERR_ROOT_COMMAND, &reg32);
1428 		reg32 |= ROOT_PORT_INTR_ON_MESG_MASK;
1429 		pci_write_config_dword(root, aer + PCI_ERR_ROOT_COMMAND, reg32);
1430 	}
1431 
1432 	return rc ? PCI_ERS_RESULT_DISCONNECT : PCI_ERS_RESULT_RECOVERED;
1433 }
1434 
1435 static struct pcie_port_service_driver aerdriver = {
1436 	.name		= "aer",
1437 	.port_type	= PCIE_ANY_PORT,
1438 	.service	= PCIE_PORT_SERVICE_AER,
1439 
1440 	.probe		= aer_probe,
1441 	.remove		= aer_remove,
1442 };
1443 
1444 /**
1445  * pcie_aer_init - register AER root service driver
1446  *
1447  * Invoked when AER root service driver is loaded.
1448  */
1449 int __init pcie_aer_init(void)
1450 {
1451 	if (!pci_aer_available())
1452 		return -ENXIO;
1453 	return pcie_port_service_register(&aerdriver);
1454 }
1455