xref: /linux/drivers/pci/pcie/aer.c (revision 722ecdbce68a87de2d9296f91308f44ea900a039)
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 #define AER_ERR_STATUS_MASK		(PCI_ERR_ROOT_UNCOR_RCV |	\
105 					PCI_ERR_ROOT_COR_RCV |		\
106 					PCI_ERR_ROOT_MULTI_COR_RCV |	\
107 					PCI_ERR_ROOT_MULTI_UNCOR_RCV)
108 
109 static int pcie_aer_disable;
110 static pci_ers_result_t aer_root_reset(struct pci_dev *dev);
111 
112 void pci_no_aer(void)
113 {
114 	pcie_aer_disable = 1;
115 }
116 
117 bool pci_aer_available(void)
118 {
119 	return !pcie_aer_disable && pci_msi_enabled();
120 }
121 
122 #ifdef CONFIG_PCIE_ECRC
123 
124 #define ECRC_POLICY_DEFAULT 0		/* ECRC set by BIOS */
125 #define ECRC_POLICY_OFF     1		/* ECRC off for performance */
126 #define ECRC_POLICY_ON      2		/* ECRC on for data integrity */
127 
128 static int ecrc_policy = ECRC_POLICY_DEFAULT;
129 
130 static const char * const ecrc_policy_str[] = {
131 	[ECRC_POLICY_DEFAULT] = "bios",
132 	[ECRC_POLICY_OFF] = "off",
133 	[ECRC_POLICY_ON] = "on"
134 };
135 
136 /**
137  * enable_ecrc_checking - enable PCIe ECRC checking for a device
138  * @dev: the PCI device
139  *
140  * Returns 0 on success, or negative on failure.
141  */
142 static int enable_ecrc_checking(struct pci_dev *dev)
143 {
144 	int aer = dev->aer_cap;
145 	u32 reg32;
146 
147 	if (!aer)
148 		return -ENODEV;
149 
150 	pci_read_config_dword(dev, aer + PCI_ERR_CAP, &reg32);
151 	if (reg32 & PCI_ERR_CAP_ECRC_GENC)
152 		reg32 |= PCI_ERR_CAP_ECRC_GENE;
153 	if (reg32 & PCI_ERR_CAP_ECRC_CHKC)
154 		reg32 |= PCI_ERR_CAP_ECRC_CHKE;
155 	pci_write_config_dword(dev, aer + PCI_ERR_CAP, reg32);
156 
157 	return 0;
158 }
159 
160 /**
161  * disable_ecrc_checking - disables PCIe ECRC checking for a device
162  * @dev: the PCI device
163  *
164  * Returns 0 on success, or negative on failure.
165  */
166 static int disable_ecrc_checking(struct pci_dev *dev)
167 {
168 	int aer = dev->aer_cap;
169 	u32 reg32;
170 
171 	if (!aer)
172 		return -ENODEV;
173 
174 	pci_read_config_dword(dev, aer + PCI_ERR_CAP, &reg32);
175 	reg32 &= ~(PCI_ERR_CAP_ECRC_GENE | PCI_ERR_CAP_ECRC_CHKE);
176 	pci_write_config_dword(dev, aer + PCI_ERR_CAP, reg32);
177 
178 	return 0;
179 }
180 
181 /**
182  * pcie_set_ecrc_checking - set/unset PCIe ECRC checking for a device based on global policy
183  * @dev: the PCI device
184  */
185 void pcie_set_ecrc_checking(struct pci_dev *dev)
186 {
187 	switch (ecrc_policy) {
188 	case ECRC_POLICY_DEFAULT:
189 		return;
190 	case ECRC_POLICY_OFF:
191 		disable_ecrc_checking(dev);
192 		break;
193 	case ECRC_POLICY_ON:
194 		enable_ecrc_checking(dev);
195 		break;
196 	default:
197 		return;
198 	}
199 }
200 
201 /**
202  * pcie_ecrc_get_policy - parse kernel command-line ecrc option
203  * @str: ECRC policy from kernel command line to use
204  */
205 void pcie_ecrc_get_policy(char *str)
206 {
207 	int i;
208 
209 	i = match_string(ecrc_policy_str, ARRAY_SIZE(ecrc_policy_str), str);
210 	if (i < 0)
211 		return;
212 
213 	ecrc_policy = i;
214 }
215 #endif	/* CONFIG_PCIE_ECRC */
216 
217 #define	PCI_EXP_AER_FLAGS	(PCI_EXP_DEVCTL_CERE | PCI_EXP_DEVCTL_NFERE | \
218 				 PCI_EXP_DEVCTL_FERE | PCI_EXP_DEVCTL_URRE)
219 
220 int pcie_aer_is_native(struct pci_dev *dev)
221 {
222 	struct pci_host_bridge *host = pci_find_host_bridge(dev->bus);
223 
224 	if (!dev->aer_cap)
225 		return 0;
226 
227 	return pcie_ports_native || host->native_aer;
228 }
229 
230 int pci_enable_pcie_error_reporting(struct pci_dev *dev)
231 {
232 	int rc;
233 
234 	if (!pcie_aer_is_native(dev))
235 		return -EIO;
236 
237 	rc = pcie_capability_set_word(dev, PCI_EXP_DEVCTL, PCI_EXP_AER_FLAGS);
238 	return pcibios_err_to_errno(rc);
239 }
240 EXPORT_SYMBOL_GPL(pci_enable_pcie_error_reporting);
241 
242 int pci_disable_pcie_error_reporting(struct pci_dev *dev)
243 {
244 	int rc;
245 
246 	if (!pcie_aer_is_native(dev))
247 		return -EIO;
248 
249 	rc = pcie_capability_clear_word(dev, PCI_EXP_DEVCTL, PCI_EXP_AER_FLAGS);
250 	return pcibios_err_to_errno(rc);
251 }
252 EXPORT_SYMBOL_GPL(pci_disable_pcie_error_reporting);
253 
254 int pci_aer_clear_nonfatal_status(struct pci_dev *dev)
255 {
256 	int aer = dev->aer_cap;
257 	u32 status, sev;
258 
259 	if (!pcie_aer_is_native(dev))
260 		return -EIO;
261 
262 	/* Clear status bits for ERR_NONFATAL errors only */
263 	pci_read_config_dword(dev, aer + PCI_ERR_UNCOR_STATUS, &status);
264 	pci_read_config_dword(dev, aer + PCI_ERR_UNCOR_SEVER, &sev);
265 	status &= ~sev;
266 	if (status)
267 		pci_write_config_dword(dev, aer + PCI_ERR_UNCOR_STATUS, status);
268 
269 	return 0;
270 }
271 EXPORT_SYMBOL_GPL(pci_aer_clear_nonfatal_status);
272 
273 void pci_aer_clear_fatal_status(struct pci_dev *dev)
274 {
275 	int aer = dev->aer_cap;
276 	u32 status, sev;
277 
278 	if (!pcie_aer_is_native(dev))
279 		return;
280 
281 	/* Clear status bits for ERR_FATAL errors only */
282 	pci_read_config_dword(dev, aer + PCI_ERR_UNCOR_STATUS, &status);
283 	pci_read_config_dword(dev, aer + PCI_ERR_UNCOR_SEVER, &sev);
284 	status &= sev;
285 	if (status)
286 		pci_write_config_dword(dev, aer + PCI_ERR_UNCOR_STATUS, status);
287 }
288 
289 /**
290  * pci_aer_raw_clear_status - Clear AER error registers.
291  * @dev: the PCI device
292  *
293  * Clearing AER error status registers unconditionally, regardless of
294  * whether they're owned by firmware or the OS.
295  *
296  * Returns 0 on success, or negative on failure.
297  */
298 int pci_aer_raw_clear_status(struct pci_dev *dev)
299 {
300 	int aer = dev->aer_cap;
301 	u32 status;
302 	int port_type;
303 
304 	if (!aer)
305 		return -EIO;
306 
307 	port_type = pci_pcie_type(dev);
308 	if (port_type == PCI_EXP_TYPE_ROOT_PORT ||
309 	    port_type == PCI_EXP_TYPE_RC_EC) {
310 		pci_read_config_dword(dev, aer + PCI_ERR_ROOT_STATUS, &status);
311 		pci_write_config_dword(dev, aer + PCI_ERR_ROOT_STATUS, status);
312 	}
313 
314 	pci_read_config_dword(dev, aer + PCI_ERR_COR_STATUS, &status);
315 	pci_write_config_dword(dev, aer + PCI_ERR_COR_STATUS, status);
316 
317 	pci_read_config_dword(dev, aer + PCI_ERR_UNCOR_STATUS, &status);
318 	pci_write_config_dword(dev, aer + PCI_ERR_UNCOR_STATUS, status);
319 
320 	return 0;
321 }
322 
323 int pci_aer_clear_status(struct pci_dev *dev)
324 {
325 	if (!pcie_aer_is_native(dev))
326 		return -EIO;
327 
328 	return pci_aer_raw_clear_status(dev);
329 }
330 
331 void pci_save_aer_state(struct pci_dev *dev)
332 {
333 	int aer = dev->aer_cap;
334 	struct pci_cap_saved_state *save_state;
335 	u32 *cap;
336 
337 	if (!aer)
338 		return;
339 
340 	save_state = pci_find_saved_ext_cap(dev, PCI_EXT_CAP_ID_ERR);
341 	if (!save_state)
342 		return;
343 
344 	cap = &save_state->cap.data[0];
345 	pci_read_config_dword(dev, aer + PCI_ERR_UNCOR_MASK, cap++);
346 	pci_read_config_dword(dev, aer + PCI_ERR_UNCOR_SEVER, cap++);
347 	pci_read_config_dword(dev, aer + PCI_ERR_COR_MASK, cap++);
348 	pci_read_config_dword(dev, aer + PCI_ERR_CAP, cap++);
349 	if (pcie_cap_has_rtctl(dev))
350 		pci_read_config_dword(dev, aer + PCI_ERR_ROOT_COMMAND, cap++);
351 }
352 
353 void pci_restore_aer_state(struct pci_dev *dev)
354 {
355 	int aer = dev->aer_cap;
356 	struct pci_cap_saved_state *save_state;
357 	u32 *cap;
358 
359 	if (!aer)
360 		return;
361 
362 	save_state = pci_find_saved_ext_cap(dev, PCI_EXT_CAP_ID_ERR);
363 	if (!save_state)
364 		return;
365 
366 	cap = &save_state->cap.data[0];
367 	pci_write_config_dword(dev, aer + PCI_ERR_UNCOR_MASK, *cap++);
368 	pci_write_config_dword(dev, aer + PCI_ERR_UNCOR_SEVER, *cap++);
369 	pci_write_config_dword(dev, aer + PCI_ERR_COR_MASK, *cap++);
370 	pci_write_config_dword(dev, aer + PCI_ERR_CAP, *cap++);
371 	if (pcie_cap_has_rtctl(dev))
372 		pci_write_config_dword(dev, aer + PCI_ERR_ROOT_COMMAND, *cap++);
373 }
374 
375 void pci_aer_init(struct pci_dev *dev)
376 {
377 	int n;
378 
379 	dev->aer_cap = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ERR);
380 	if (!dev->aer_cap)
381 		return;
382 
383 	dev->aer_stats = kzalloc(sizeof(struct aer_stats), GFP_KERNEL);
384 
385 	/*
386 	 * We save/restore PCI_ERR_UNCOR_MASK, PCI_ERR_UNCOR_SEVER,
387 	 * PCI_ERR_COR_MASK, and PCI_ERR_CAP.  Root and Root Complex Event
388 	 * Collectors also implement PCI_ERR_ROOT_COMMAND (PCIe r5.0, sec
389 	 * 7.8.4).
390 	 */
391 	n = pcie_cap_has_rtctl(dev) ? 5 : 4;
392 	pci_add_ext_cap_save_buffer(dev, PCI_EXT_CAP_ID_ERR, sizeof(u32) * n);
393 
394 	pci_aer_clear_status(dev);
395 }
396 
397 void pci_aer_exit(struct pci_dev *dev)
398 {
399 	kfree(dev->aer_stats);
400 	dev->aer_stats = NULL;
401 }
402 
403 #define AER_AGENT_RECEIVER		0
404 #define AER_AGENT_REQUESTER		1
405 #define AER_AGENT_COMPLETER		2
406 #define AER_AGENT_TRANSMITTER		3
407 
408 #define AER_AGENT_REQUESTER_MASK(t)	((t == AER_CORRECTABLE) ?	\
409 	0 : (PCI_ERR_UNC_COMP_TIME|PCI_ERR_UNC_UNSUP))
410 #define AER_AGENT_COMPLETER_MASK(t)	((t == AER_CORRECTABLE) ?	\
411 	0 : PCI_ERR_UNC_COMP_ABORT)
412 #define AER_AGENT_TRANSMITTER_MASK(t)	((t == AER_CORRECTABLE) ?	\
413 	(PCI_ERR_COR_REP_ROLL|PCI_ERR_COR_REP_TIMER) : 0)
414 
415 #define AER_GET_AGENT(t, e)						\
416 	((e & AER_AGENT_COMPLETER_MASK(t)) ? AER_AGENT_COMPLETER :	\
417 	(e & AER_AGENT_REQUESTER_MASK(t)) ? AER_AGENT_REQUESTER :	\
418 	(e & AER_AGENT_TRANSMITTER_MASK(t)) ? AER_AGENT_TRANSMITTER :	\
419 	AER_AGENT_RECEIVER)
420 
421 #define AER_PHYSICAL_LAYER_ERROR	0
422 #define AER_DATA_LINK_LAYER_ERROR	1
423 #define AER_TRANSACTION_LAYER_ERROR	2
424 
425 #define AER_PHYSICAL_LAYER_ERROR_MASK(t) ((t == AER_CORRECTABLE) ?	\
426 	PCI_ERR_COR_RCVR : 0)
427 #define AER_DATA_LINK_LAYER_ERROR_MASK(t) ((t == AER_CORRECTABLE) ?	\
428 	(PCI_ERR_COR_BAD_TLP|						\
429 	PCI_ERR_COR_BAD_DLLP|						\
430 	PCI_ERR_COR_REP_ROLL|						\
431 	PCI_ERR_COR_REP_TIMER) : PCI_ERR_UNC_DLP)
432 
433 #define AER_GET_LAYER_ERROR(t, e)					\
434 	((e & AER_PHYSICAL_LAYER_ERROR_MASK(t)) ? AER_PHYSICAL_LAYER_ERROR : \
435 	(e & AER_DATA_LINK_LAYER_ERROR_MASK(t)) ? AER_DATA_LINK_LAYER_ERROR : \
436 	AER_TRANSACTION_LAYER_ERROR)
437 
438 /*
439  * AER error strings
440  */
441 static const char *aer_error_severity_string[] = {
442 	"Uncorrected (Non-Fatal)",
443 	"Uncorrected (Fatal)",
444 	"Corrected"
445 };
446 
447 static const char *aer_error_layer[] = {
448 	"Physical Layer",
449 	"Data Link Layer",
450 	"Transaction Layer"
451 };
452 
453 static const char *aer_correctable_error_string[] = {
454 	"RxErr",			/* Bit Position 0	*/
455 	NULL,
456 	NULL,
457 	NULL,
458 	NULL,
459 	NULL,
460 	"BadTLP",			/* Bit Position 6	*/
461 	"BadDLLP",			/* Bit Position 7	*/
462 	"Rollover",			/* Bit Position 8	*/
463 	NULL,
464 	NULL,
465 	NULL,
466 	"Timeout",			/* Bit Position 12	*/
467 	"NonFatalErr",			/* Bit Position 13	*/
468 	"CorrIntErr",			/* Bit Position 14	*/
469 	"HeaderOF",			/* Bit Position 15	*/
470 	NULL,				/* Bit Position 16	*/
471 	NULL,				/* Bit Position 17	*/
472 	NULL,				/* Bit Position 18	*/
473 	NULL,				/* Bit Position 19	*/
474 	NULL,				/* Bit Position 20	*/
475 	NULL,				/* Bit Position 21	*/
476 	NULL,				/* Bit Position 22	*/
477 	NULL,				/* Bit Position 23	*/
478 	NULL,				/* Bit Position 24	*/
479 	NULL,				/* Bit Position 25	*/
480 	NULL,				/* Bit Position 26	*/
481 	NULL,				/* Bit Position 27	*/
482 	NULL,				/* Bit Position 28	*/
483 	NULL,				/* Bit Position 29	*/
484 	NULL,				/* Bit Position 30	*/
485 	NULL,				/* Bit Position 31	*/
486 };
487 
488 static const char *aer_uncorrectable_error_string[] = {
489 	"Undefined",			/* Bit Position 0	*/
490 	NULL,
491 	NULL,
492 	NULL,
493 	"DLP",				/* Bit Position 4	*/
494 	"SDES",				/* Bit Position 5	*/
495 	NULL,
496 	NULL,
497 	NULL,
498 	NULL,
499 	NULL,
500 	NULL,
501 	"TLP",				/* Bit Position 12	*/
502 	"FCP",				/* Bit Position 13	*/
503 	"CmpltTO",			/* Bit Position 14	*/
504 	"CmpltAbrt",			/* Bit Position 15	*/
505 	"UnxCmplt",			/* Bit Position 16	*/
506 	"RxOF",				/* Bit Position 17	*/
507 	"MalfTLP",			/* Bit Position 18	*/
508 	"ECRC",				/* Bit Position 19	*/
509 	"UnsupReq",			/* Bit Position 20	*/
510 	"ACSViol",			/* Bit Position 21	*/
511 	"UncorrIntErr",			/* Bit Position 22	*/
512 	"BlockedTLP",			/* Bit Position 23	*/
513 	"AtomicOpBlocked",		/* Bit Position 24	*/
514 	"TLPBlockedErr",		/* Bit Position 25	*/
515 	"PoisonTLPBlocked",		/* Bit Position 26	*/
516 	NULL,				/* Bit Position 27	*/
517 	NULL,				/* Bit Position 28	*/
518 	NULL,				/* Bit Position 29	*/
519 	NULL,				/* Bit Position 30	*/
520 	NULL,				/* Bit Position 31	*/
521 };
522 
523 static const char *aer_agent_string[] = {
524 	"Receiver ID",
525 	"Requester ID",
526 	"Completer ID",
527 	"Transmitter ID"
528 };
529 
530 #define aer_stats_dev_attr(name, stats_array, strings_array,		\
531 			   total_string, total_field)			\
532 	static ssize_t							\
533 	name##_show(struct device *dev, struct device_attribute *attr,	\
534 		     char *buf)						\
535 {									\
536 	unsigned int i;							\
537 	struct pci_dev *pdev = to_pci_dev(dev);				\
538 	u64 *stats = pdev->aer_stats->stats_array;			\
539 	size_t len = 0;							\
540 									\
541 	for (i = 0; i < ARRAY_SIZE(strings_array); i++) {		\
542 		if (strings_array[i])					\
543 			len += sysfs_emit_at(buf, len, "%s %llu\n",	\
544 					     strings_array[i],		\
545 					     stats[i]);			\
546 		else if (stats[i])					\
547 			len += sysfs_emit_at(buf, len,			\
548 					     #stats_array "_bit[%d] %llu\n",\
549 					     i, stats[i]);		\
550 	}								\
551 	len += sysfs_emit_at(buf, len, "TOTAL_%s %llu\n", total_string,	\
552 			     pdev->aer_stats->total_field);		\
553 	return len;							\
554 }									\
555 static DEVICE_ATTR_RO(name)
556 
557 aer_stats_dev_attr(aer_dev_correctable, dev_cor_errs,
558 		   aer_correctable_error_string, "ERR_COR",
559 		   dev_total_cor_errs);
560 aer_stats_dev_attr(aer_dev_fatal, dev_fatal_errs,
561 		   aer_uncorrectable_error_string, "ERR_FATAL",
562 		   dev_total_fatal_errs);
563 aer_stats_dev_attr(aer_dev_nonfatal, dev_nonfatal_errs,
564 		   aer_uncorrectable_error_string, "ERR_NONFATAL",
565 		   dev_total_nonfatal_errs);
566 
567 #define aer_stats_rootport_attr(name, field)				\
568 	static ssize_t							\
569 	name##_show(struct device *dev, struct device_attribute *attr,	\
570 		     char *buf)						\
571 {									\
572 	struct pci_dev *pdev = to_pci_dev(dev);				\
573 	return sysfs_emit(buf, "%llu\n", pdev->aer_stats->field);	\
574 }									\
575 static DEVICE_ATTR_RO(name)
576 
577 aer_stats_rootport_attr(aer_rootport_total_err_cor,
578 			 rootport_total_cor_errs);
579 aer_stats_rootport_attr(aer_rootport_total_err_fatal,
580 			 rootport_total_fatal_errs);
581 aer_stats_rootport_attr(aer_rootport_total_err_nonfatal,
582 			 rootport_total_nonfatal_errs);
583 
584 static struct attribute *aer_stats_attrs[] __ro_after_init = {
585 	&dev_attr_aer_dev_correctable.attr,
586 	&dev_attr_aer_dev_fatal.attr,
587 	&dev_attr_aer_dev_nonfatal.attr,
588 	&dev_attr_aer_rootport_total_err_cor.attr,
589 	&dev_attr_aer_rootport_total_err_fatal.attr,
590 	&dev_attr_aer_rootport_total_err_nonfatal.attr,
591 	NULL
592 };
593 
594 static umode_t aer_stats_attrs_are_visible(struct kobject *kobj,
595 					   struct attribute *a, int n)
596 {
597 	struct device *dev = kobj_to_dev(kobj);
598 	struct pci_dev *pdev = to_pci_dev(dev);
599 
600 	if (!pdev->aer_stats)
601 		return 0;
602 
603 	if ((a == &dev_attr_aer_rootport_total_err_cor.attr ||
604 	     a == &dev_attr_aer_rootport_total_err_fatal.attr ||
605 	     a == &dev_attr_aer_rootport_total_err_nonfatal.attr) &&
606 	    ((pci_pcie_type(pdev) != PCI_EXP_TYPE_ROOT_PORT) &&
607 	     (pci_pcie_type(pdev) != PCI_EXP_TYPE_RC_EC)))
608 		return 0;
609 
610 	return a->mode;
611 }
612 
613 const struct attribute_group aer_stats_attr_group = {
614 	.attrs  = aer_stats_attrs,
615 	.is_visible = aer_stats_attrs_are_visible,
616 };
617 
618 static void pci_dev_aer_stats_incr(struct pci_dev *pdev,
619 				   struct aer_err_info *info)
620 {
621 	unsigned long status = info->status & ~info->mask;
622 	int i, max = -1;
623 	u64 *counter = NULL;
624 	struct aer_stats *aer_stats = pdev->aer_stats;
625 
626 	if (!aer_stats)
627 		return;
628 
629 	switch (info->severity) {
630 	case AER_CORRECTABLE:
631 		aer_stats->dev_total_cor_errs++;
632 		counter = &aer_stats->dev_cor_errs[0];
633 		max = AER_MAX_TYPEOF_COR_ERRS;
634 		break;
635 	case AER_NONFATAL:
636 		aer_stats->dev_total_nonfatal_errs++;
637 		counter = &aer_stats->dev_nonfatal_errs[0];
638 		max = AER_MAX_TYPEOF_UNCOR_ERRS;
639 		break;
640 	case AER_FATAL:
641 		aer_stats->dev_total_fatal_errs++;
642 		counter = &aer_stats->dev_fatal_errs[0];
643 		max = AER_MAX_TYPEOF_UNCOR_ERRS;
644 		break;
645 	}
646 
647 	for_each_set_bit(i, &status, max)
648 		counter[i]++;
649 }
650 
651 static void pci_rootport_aer_stats_incr(struct pci_dev *pdev,
652 				 struct aer_err_source *e_src)
653 {
654 	struct aer_stats *aer_stats = pdev->aer_stats;
655 
656 	if (!aer_stats)
657 		return;
658 
659 	if (e_src->status & PCI_ERR_ROOT_COR_RCV)
660 		aer_stats->rootport_total_cor_errs++;
661 
662 	if (e_src->status & PCI_ERR_ROOT_UNCOR_RCV) {
663 		if (e_src->status & PCI_ERR_ROOT_FATAL_RCV)
664 			aer_stats->rootport_total_fatal_errs++;
665 		else
666 			aer_stats->rootport_total_nonfatal_errs++;
667 	}
668 }
669 
670 static void __print_tlp_header(struct pci_dev *dev,
671 			       struct aer_header_log_regs *t)
672 {
673 	pci_err(dev, "  TLP Header: %08x %08x %08x %08x\n",
674 		t->dw0, t->dw1, t->dw2, t->dw3);
675 }
676 
677 static void __aer_print_error(struct pci_dev *dev,
678 			      struct aer_err_info *info)
679 {
680 	const char **strings;
681 	unsigned long status = info->status & ~info->mask;
682 	const char *level, *errmsg;
683 	int i;
684 
685 	if (info->severity == AER_CORRECTABLE) {
686 		strings = aer_correctable_error_string;
687 		level = KERN_WARNING;
688 	} else {
689 		strings = aer_uncorrectable_error_string;
690 		level = KERN_ERR;
691 	}
692 
693 	for_each_set_bit(i, &status, 32) {
694 		errmsg = strings[i];
695 		if (!errmsg)
696 			errmsg = "Unknown Error Bit";
697 
698 		pci_printk(level, dev, "   [%2d] %-22s%s\n", i, errmsg,
699 				info->first_error == i ? " (First)" : "");
700 	}
701 	pci_dev_aer_stats_incr(dev, info);
702 }
703 
704 void aer_print_error(struct pci_dev *dev, struct aer_err_info *info)
705 {
706 	int layer, agent;
707 	int id = ((dev->bus->number << 8) | dev->devfn);
708 	const char *level;
709 
710 	if (!info->status) {
711 		pci_err(dev, "PCIe Bus Error: severity=%s, type=Inaccessible, (Unregistered Agent ID)\n",
712 			aer_error_severity_string[info->severity]);
713 		goto out;
714 	}
715 
716 	layer = AER_GET_LAYER_ERROR(info->severity, info->status);
717 	agent = AER_GET_AGENT(info->severity, info->status);
718 
719 	level = (info->severity == AER_CORRECTABLE) ? KERN_WARNING : KERN_ERR;
720 
721 	pci_printk(level, dev, "PCIe Bus Error: severity=%s, type=%s, (%s)\n",
722 		   aer_error_severity_string[info->severity],
723 		   aer_error_layer[layer], aer_agent_string[agent]);
724 
725 	pci_printk(level, dev, "  device [%04x:%04x] error status/mask=%08x/%08x\n",
726 		   dev->vendor, dev->device, info->status, info->mask);
727 
728 	__aer_print_error(dev, info);
729 
730 	if (info->tlp_header_valid)
731 		__print_tlp_header(dev, &info->tlp);
732 
733 out:
734 	if (info->id && info->error_dev_num > 1 && info->id == id)
735 		pci_err(dev, "  Error of this Agent is reported first\n");
736 
737 	trace_aer_event(dev_name(&dev->dev), (info->status & ~info->mask),
738 			info->severity, info->tlp_header_valid, &info->tlp);
739 }
740 
741 static void aer_print_port_info(struct pci_dev *dev, struct aer_err_info *info)
742 {
743 	u8 bus = info->id >> 8;
744 	u8 devfn = info->id & 0xff;
745 
746 	pci_info(dev, "%s%s error received: %04x:%02x:%02x.%d\n",
747 		 info->multi_error_valid ? "Multiple " : "",
748 		 aer_error_severity_string[info->severity],
749 		 pci_domain_nr(dev->bus), bus, PCI_SLOT(devfn),
750 		 PCI_FUNC(devfn));
751 }
752 
753 #ifdef CONFIG_ACPI_APEI_PCIEAER
754 int cper_severity_to_aer(int cper_severity)
755 {
756 	switch (cper_severity) {
757 	case CPER_SEV_RECOVERABLE:
758 		return AER_NONFATAL;
759 	case CPER_SEV_FATAL:
760 		return AER_FATAL;
761 	default:
762 		return AER_CORRECTABLE;
763 	}
764 }
765 EXPORT_SYMBOL_GPL(cper_severity_to_aer);
766 
767 void cper_print_aer(struct pci_dev *dev, int aer_severity,
768 		    struct aer_capability_regs *aer)
769 {
770 	int layer, agent, tlp_header_valid = 0;
771 	u32 status, mask;
772 	struct aer_err_info info;
773 
774 	if (aer_severity == AER_CORRECTABLE) {
775 		status = aer->cor_status;
776 		mask = aer->cor_mask;
777 	} else {
778 		status = aer->uncor_status;
779 		mask = aer->uncor_mask;
780 		tlp_header_valid = status & AER_LOG_TLP_MASKS;
781 	}
782 
783 	layer = AER_GET_LAYER_ERROR(aer_severity, status);
784 	agent = AER_GET_AGENT(aer_severity, status);
785 
786 	memset(&info, 0, sizeof(info));
787 	info.severity = aer_severity;
788 	info.status = status;
789 	info.mask = mask;
790 	info.first_error = PCI_ERR_CAP_FEP(aer->cap_control);
791 
792 	pci_err(dev, "aer_status: 0x%08x, aer_mask: 0x%08x\n", status, mask);
793 	__aer_print_error(dev, &info);
794 	pci_err(dev, "aer_layer=%s, aer_agent=%s\n",
795 		aer_error_layer[layer], aer_agent_string[agent]);
796 
797 	if (aer_severity != AER_CORRECTABLE)
798 		pci_err(dev, "aer_uncor_severity: 0x%08x\n",
799 			aer->uncor_severity);
800 
801 	if (tlp_header_valid)
802 		__print_tlp_header(dev, &aer->header_log);
803 
804 	trace_aer_event(dev_name(&dev->dev), (status & ~mask),
805 			aer_severity, tlp_header_valid, &aer->header_log);
806 }
807 #endif
808 
809 /**
810  * add_error_device - list device to be handled
811  * @e_info: pointer to error info
812  * @dev: pointer to pci_dev to be added
813  */
814 static int add_error_device(struct aer_err_info *e_info, struct pci_dev *dev)
815 {
816 	if (e_info->error_dev_num < AER_MAX_MULTI_ERR_DEVICES) {
817 		e_info->dev[e_info->error_dev_num] = pci_dev_get(dev);
818 		e_info->error_dev_num++;
819 		return 0;
820 	}
821 	return -ENOSPC;
822 }
823 
824 /**
825  * is_error_source - check whether the device is source of reported error
826  * @dev: pointer to pci_dev to be checked
827  * @e_info: pointer to reported error info
828  */
829 static bool is_error_source(struct pci_dev *dev, struct aer_err_info *e_info)
830 {
831 	int aer = dev->aer_cap;
832 	u32 status, mask;
833 	u16 reg16;
834 
835 	/*
836 	 * When bus id is equal to 0, it might be a bad id
837 	 * reported by root port.
838 	 */
839 	if ((PCI_BUS_NUM(e_info->id) != 0) &&
840 	    !(dev->bus->bus_flags & PCI_BUS_FLAGS_NO_AERSID)) {
841 		/* Device ID match? */
842 		if (e_info->id == ((dev->bus->number << 8) | dev->devfn))
843 			return true;
844 
845 		/* Continue id comparing if there is no multiple error */
846 		if (!e_info->multi_error_valid)
847 			return false;
848 	}
849 
850 	/*
851 	 * When either
852 	 *      1) bus id is equal to 0. Some ports might lose the bus
853 	 *              id of error source id;
854 	 *      2) bus flag PCI_BUS_FLAGS_NO_AERSID is set
855 	 *      3) There are multiple errors and prior ID comparing fails;
856 	 * We check AER status registers to find possible reporter.
857 	 */
858 	if (atomic_read(&dev->enable_cnt) == 0)
859 		return false;
860 
861 	/* Check if AER is enabled */
862 	pcie_capability_read_word(dev, PCI_EXP_DEVCTL, &reg16);
863 	if (!(reg16 & PCI_EXP_AER_FLAGS))
864 		return false;
865 
866 	if (!aer)
867 		return false;
868 
869 	/* Check if error is recorded */
870 	if (e_info->severity == AER_CORRECTABLE) {
871 		pci_read_config_dword(dev, aer + PCI_ERR_COR_STATUS, &status);
872 		pci_read_config_dword(dev, aer + PCI_ERR_COR_MASK, &mask);
873 	} else {
874 		pci_read_config_dword(dev, aer + PCI_ERR_UNCOR_STATUS, &status);
875 		pci_read_config_dword(dev, aer + PCI_ERR_UNCOR_MASK, &mask);
876 	}
877 	if (status & ~mask)
878 		return true;
879 
880 	return false;
881 }
882 
883 static int find_device_iter(struct pci_dev *dev, void *data)
884 {
885 	struct aer_err_info *e_info = (struct aer_err_info *)data;
886 
887 	if (is_error_source(dev, e_info)) {
888 		/* List this device */
889 		if (add_error_device(e_info, dev)) {
890 			/* We cannot handle more... Stop iteration */
891 			/* TODO: Should print error message here? */
892 			return 1;
893 		}
894 
895 		/* If there is only a single error, stop iteration */
896 		if (!e_info->multi_error_valid)
897 			return 1;
898 	}
899 	return 0;
900 }
901 
902 /**
903  * find_source_device - search through device hierarchy for source device
904  * @parent: pointer to Root Port pci_dev data structure
905  * @e_info: including detailed error information such like id
906  *
907  * Return true if found.
908  *
909  * Invoked by DPC when error is detected at the Root Port.
910  * Caller of this function must set id, severity, and multi_error_valid of
911  * struct aer_err_info pointed by @e_info properly.  This function must fill
912  * e_info->error_dev_num and e_info->dev[], based on the given information.
913  */
914 static bool find_source_device(struct pci_dev *parent,
915 		struct aer_err_info *e_info)
916 {
917 	struct pci_dev *dev = parent;
918 	int result;
919 
920 	/* Must reset in this function */
921 	e_info->error_dev_num = 0;
922 
923 	/* Is Root Port an agent that sends error message? */
924 	result = find_device_iter(dev, e_info);
925 	if (result)
926 		return true;
927 
928 	if (pci_pcie_type(parent) == PCI_EXP_TYPE_RC_EC)
929 		pcie_walk_rcec(parent, find_device_iter, e_info);
930 	else
931 		pci_walk_bus(parent->subordinate, find_device_iter, e_info);
932 
933 	if (!e_info->error_dev_num) {
934 		pci_info(parent, "can't find device of ID%04x\n", e_info->id);
935 		return false;
936 	}
937 	return true;
938 }
939 
940 /**
941  * handle_error_source - handle logging error into an event log
942  * @dev: pointer to pci_dev data structure of error source device
943  * @info: comprehensive error information
944  *
945  * Invoked when an error being detected by Root Port.
946  */
947 static void handle_error_source(struct pci_dev *dev, struct aer_err_info *info)
948 {
949 	int aer = dev->aer_cap;
950 
951 	if (info->severity == AER_CORRECTABLE) {
952 		/*
953 		 * Correctable error does not need software intervention.
954 		 * No need to go through error recovery process.
955 		 */
956 		if (aer)
957 			pci_write_config_dword(dev, aer + PCI_ERR_COR_STATUS,
958 					info->status);
959 		if (pcie_aer_is_native(dev))
960 			pcie_clear_device_status(dev);
961 	} else if (info->severity == AER_NONFATAL)
962 		pcie_do_recovery(dev, pci_channel_io_normal, aer_root_reset);
963 	else if (info->severity == AER_FATAL)
964 		pcie_do_recovery(dev, pci_channel_io_frozen, aer_root_reset);
965 	pci_dev_put(dev);
966 }
967 
968 #ifdef CONFIG_ACPI_APEI_PCIEAER
969 
970 #define AER_RECOVER_RING_ORDER		4
971 #define AER_RECOVER_RING_SIZE		(1 << AER_RECOVER_RING_ORDER)
972 
973 struct aer_recover_entry {
974 	u8	bus;
975 	u8	devfn;
976 	u16	domain;
977 	int	severity;
978 	struct aer_capability_regs *regs;
979 };
980 
981 static DEFINE_KFIFO(aer_recover_ring, struct aer_recover_entry,
982 		    AER_RECOVER_RING_SIZE);
983 
984 static void aer_recover_work_func(struct work_struct *work)
985 {
986 	struct aer_recover_entry entry;
987 	struct pci_dev *pdev;
988 
989 	while (kfifo_get(&aer_recover_ring, &entry)) {
990 		pdev = pci_get_domain_bus_and_slot(entry.domain, entry.bus,
991 						   entry.devfn);
992 		if (!pdev) {
993 			pr_err("no pci_dev for %04x:%02x:%02x.%x\n",
994 			       entry.domain, entry.bus,
995 			       PCI_SLOT(entry.devfn), PCI_FUNC(entry.devfn));
996 			continue;
997 		}
998 		cper_print_aer(pdev, entry.severity, entry.regs);
999 		if (entry.severity == AER_NONFATAL)
1000 			pcie_do_recovery(pdev, pci_channel_io_normal,
1001 					 aer_root_reset);
1002 		else if (entry.severity == AER_FATAL)
1003 			pcie_do_recovery(pdev, pci_channel_io_frozen,
1004 					 aer_root_reset);
1005 		pci_dev_put(pdev);
1006 	}
1007 }
1008 
1009 /*
1010  * Mutual exclusion for writers of aer_recover_ring, reader side don't
1011  * need lock, because there is only one reader and lock is not needed
1012  * between reader and writer.
1013  */
1014 static DEFINE_SPINLOCK(aer_recover_ring_lock);
1015 static DECLARE_WORK(aer_recover_work, aer_recover_work_func);
1016 
1017 void aer_recover_queue(int domain, unsigned int bus, unsigned int devfn,
1018 		       int severity, struct aer_capability_regs *aer_regs)
1019 {
1020 	struct aer_recover_entry entry = {
1021 		.bus		= bus,
1022 		.devfn		= devfn,
1023 		.domain		= domain,
1024 		.severity	= severity,
1025 		.regs		= aer_regs,
1026 	};
1027 
1028 	if (kfifo_in_spinlocked(&aer_recover_ring, &entry, 1,
1029 				 &aer_recover_ring_lock))
1030 		schedule_work(&aer_recover_work);
1031 	else
1032 		pr_err("buffer overflow in recovery for %04x:%02x:%02x.%x\n",
1033 		       domain, bus, PCI_SLOT(devfn), PCI_FUNC(devfn));
1034 }
1035 EXPORT_SYMBOL_GPL(aer_recover_queue);
1036 #endif
1037 
1038 /**
1039  * aer_get_device_error_info - read error status from dev and store it to info
1040  * @dev: pointer to the device expected to have a error record
1041  * @info: pointer to structure to store the error record
1042  *
1043  * Return 1 on success, 0 on error.
1044  *
1045  * Note that @info is reused among all error devices. Clear fields properly.
1046  */
1047 int aer_get_device_error_info(struct pci_dev *dev, struct aer_err_info *info)
1048 {
1049 	int type = pci_pcie_type(dev);
1050 	int aer = dev->aer_cap;
1051 	int temp;
1052 
1053 	/* Must reset in this function */
1054 	info->status = 0;
1055 	info->tlp_header_valid = 0;
1056 
1057 	/* The device might not support AER */
1058 	if (!aer)
1059 		return 0;
1060 
1061 	if (info->severity == AER_CORRECTABLE) {
1062 		pci_read_config_dword(dev, aer + PCI_ERR_COR_STATUS,
1063 			&info->status);
1064 		pci_read_config_dword(dev, aer + PCI_ERR_COR_MASK,
1065 			&info->mask);
1066 		if (!(info->status & ~info->mask))
1067 			return 0;
1068 	} else if (type == PCI_EXP_TYPE_ROOT_PORT ||
1069 		   type == PCI_EXP_TYPE_RC_EC ||
1070 		   type == PCI_EXP_TYPE_DOWNSTREAM ||
1071 		   info->severity == AER_NONFATAL) {
1072 
1073 		/* Link is still healthy for IO reads */
1074 		pci_read_config_dword(dev, aer + PCI_ERR_UNCOR_STATUS,
1075 			&info->status);
1076 		pci_read_config_dword(dev, aer + PCI_ERR_UNCOR_MASK,
1077 			&info->mask);
1078 		if (!(info->status & ~info->mask))
1079 			return 0;
1080 
1081 		/* Get First Error Pointer */
1082 		pci_read_config_dword(dev, aer + PCI_ERR_CAP, &temp);
1083 		info->first_error = PCI_ERR_CAP_FEP(temp);
1084 
1085 		if (info->status & AER_LOG_TLP_MASKS) {
1086 			info->tlp_header_valid = 1;
1087 			pci_read_config_dword(dev,
1088 				aer + PCI_ERR_HEADER_LOG, &info->tlp.dw0);
1089 			pci_read_config_dword(dev,
1090 				aer + PCI_ERR_HEADER_LOG + 4, &info->tlp.dw1);
1091 			pci_read_config_dword(dev,
1092 				aer + PCI_ERR_HEADER_LOG + 8, &info->tlp.dw2);
1093 			pci_read_config_dword(dev,
1094 				aer + PCI_ERR_HEADER_LOG + 12, &info->tlp.dw3);
1095 		}
1096 	}
1097 
1098 	return 1;
1099 }
1100 
1101 static inline void aer_process_err_devices(struct aer_err_info *e_info)
1102 {
1103 	int i;
1104 
1105 	/* Report all before handle them, not to lost records by reset etc. */
1106 	for (i = 0; i < e_info->error_dev_num && e_info->dev[i]; i++) {
1107 		if (aer_get_device_error_info(e_info->dev[i], e_info))
1108 			aer_print_error(e_info->dev[i], e_info);
1109 	}
1110 	for (i = 0; i < e_info->error_dev_num && e_info->dev[i]; i++) {
1111 		if (aer_get_device_error_info(e_info->dev[i], e_info))
1112 			handle_error_source(e_info->dev[i], e_info);
1113 	}
1114 }
1115 
1116 /**
1117  * aer_isr_one_error - consume an error detected by root port
1118  * @rpc: pointer to the root port which holds an error
1119  * @e_src: pointer to an error source
1120  */
1121 static void aer_isr_one_error(struct aer_rpc *rpc,
1122 		struct aer_err_source *e_src)
1123 {
1124 	struct pci_dev *pdev = rpc->rpd;
1125 	struct aer_err_info e_info;
1126 
1127 	pci_rootport_aer_stats_incr(pdev, e_src);
1128 
1129 	/*
1130 	 * There is a possibility that both correctable error and
1131 	 * uncorrectable error being logged. Report correctable error first.
1132 	 */
1133 	if (e_src->status & PCI_ERR_ROOT_COR_RCV) {
1134 		e_info.id = ERR_COR_ID(e_src->id);
1135 		e_info.severity = AER_CORRECTABLE;
1136 
1137 		if (e_src->status & PCI_ERR_ROOT_MULTI_COR_RCV)
1138 			e_info.multi_error_valid = 1;
1139 		else
1140 			e_info.multi_error_valid = 0;
1141 		aer_print_port_info(pdev, &e_info);
1142 
1143 		if (find_source_device(pdev, &e_info))
1144 			aer_process_err_devices(&e_info);
1145 	}
1146 
1147 	if (e_src->status & PCI_ERR_ROOT_UNCOR_RCV) {
1148 		e_info.id = ERR_UNCOR_ID(e_src->id);
1149 
1150 		if (e_src->status & PCI_ERR_ROOT_FATAL_RCV)
1151 			e_info.severity = AER_FATAL;
1152 		else
1153 			e_info.severity = AER_NONFATAL;
1154 
1155 		if (e_src->status & PCI_ERR_ROOT_MULTI_UNCOR_RCV)
1156 			e_info.multi_error_valid = 1;
1157 		else
1158 			e_info.multi_error_valid = 0;
1159 
1160 		aer_print_port_info(pdev, &e_info);
1161 
1162 		if (find_source_device(pdev, &e_info))
1163 			aer_process_err_devices(&e_info);
1164 	}
1165 }
1166 
1167 /**
1168  * aer_isr - consume errors detected by root port
1169  * @irq: IRQ assigned to Root Port
1170  * @context: pointer to Root Port data structure
1171  *
1172  * Invoked, as DPC, when root port records new detected error
1173  */
1174 static irqreturn_t aer_isr(int irq, void *context)
1175 {
1176 	struct pcie_device *dev = (struct pcie_device *)context;
1177 	struct aer_rpc *rpc = get_service_data(dev);
1178 	struct aer_err_source e_src;
1179 
1180 	if (kfifo_is_empty(&rpc->aer_fifo))
1181 		return IRQ_NONE;
1182 
1183 	while (kfifo_get(&rpc->aer_fifo, &e_src))
1184 		aer_isr_one_error(rpc, &e_src);
1185 	return IRQ_HANDLED;
1186 }
1187 
1188 /**
1189  * aer_irq - Root Port's ISR
1190  * @irq: IRQ assigned to Root Port
1191  * @context: pointer to Root Port data structure
1192  *
1193  * Invoked when Root Port detects AER messages.
1194  */
1195 static irqreturn_t aer_irq(int irq, void *context)
1196 {
1197 	struct pcie_device *pdev = (struct pcie_device *)context;
1198 	struct aer_rpc *rpc = get_service_data(pdev);
1199 	struct pci_dev *rp = rpc->rpd;
1200 	int aer = rp->aer_cap;
1201 	struct aer_err_source e_src = {};
1202 
1203 	pci_read_config_dword(rp, aer + PCI_ERR_ROOT_STATUS, &e_src.status);
1204 	if (!(e_src.status & AER_ERR_STATUS_MASK))
1205 		return IRQ_NONE;
1206 
1207 	pci_read_config_dword(rp, aer + PCI_ERR_ROOT_ERR_SRC, &e_src.id);
1208 	pci_write_config_dword(rp, aer + PCI_ERR_ROOT_STATUS, e_src.status);
1209 
1210 	if (!kfifo_put(&rpc->aer_fifo, e_src))
1211 		return IRQ_HANDLED;
1212 
1213 	return IRQ_WAKE_THREAD;
1214 }
1215 
1216 static int set_device_error_reporting(struct pci_dev *dev, void *data)
1217 {
1218 	bool enable = *((bool *)data);
1219 	int type = pci_pcie_type(dev);
1220 
1221 	if ((type == PCI_EXP_TYPE_ROOT_PORT) ||
1222 	    (type == PCI_EXP_TYPE_RC_EC) ||
1223 	    (type == PCI_EXP_TYPE_UPSTREAM) ||
1224 	    (type == PCI_EXP_TYPE_DOWNSTREAM)) {
1225 		if (enable)
1226 			pci_enable_pcie_error_reporting(dev);
1227 		else
1228 			pci_disable_pcie_error_reporting(dev);
1229 	}
1230 
1231 	if (enable)
1232 		pcie_set_ecrc_checking(dev);
1233 
1234 	return 0;
1235 }
1236 
1237 /**
1238  * set_downstream_devices_error_reporting - enable/disable the error reporting  bits on the root port and its downstream ports.
1239  * @dev: pointer to root port's pci_dev data structure
1240  * @enable: true = enable error reporting, false = disable error reporting.
1241  */
1242 static void set_downstream_devices_error_reporting(struct pci_dev *dev,
1243 						   bool enable)
1244 {
1245 	set_device_error_reporting(dev, &enable);
1246 
1247 	if (pci_pcie_type(dev) == PCI_EXP_TYPE_RC_EC)
1248 		pcie_walk_rcec(dev, set_device_error_reporting, &enable);
1249 	else if (dev->subordinate)
1250 		pci_walk_bus(dev->subordinate, set_device_error_reporting,
1251 			     &enable);
1252 
1253 }
1254 
1255 /**
1256  * aer_enable_rootport - enable Root Port's interrupts when receiving messages
1257  * @rpc: pointer to a Root Port data structure
1258  *
1259  * Invoked when PCIe bus loads AER service driver.
1260  */
1261 static void aer_enable_rootport(struct aer_rpc *rpc)
1262 {
1263 	struct pci_dev *pdev = rpc->rpd;
1264 	int aer = pdev->aer_cap;
1265 	u16 reg16;
1266 	u32 reg32;
1267 
1268 	/* Clear PCIe Capability's Device Status */
1269 	pcie_capability_read_word(pdev, PCI_EXP_DEVSTA, &reg16);
1270 	pcie_capability_write_word(pdev, PCI_EXP_DEVSTA, reg16);
1271 
1272 	/* Disable system error generation in response to error messages */
1273 	pcie_capability_clear_word(pdev, PCI_EXP_RTCTL,
1274 				   SYSTEM_ERROR_INTR_ON_MESG_MASK);
1275 
1276 	/* Clear error status */
1277 	pci_read_config_dword(pdev, aer + PCI_ERR_ROOT_STATUS, &reg32);
1278 	pci_write_config_dword(pdev, aer + PCI_ERR_ROOT_STATUS, reg32);
1279 	pci_read_config_dword(pdev, aer + PCI_ERR_COR_STATUS, &reg32);
1280 	pci_write_config_dword(pdev, aer + PCI_ERR_COR_STATUS, reg32);
1281 	pci_read_config_dword(pdev, aer + PCI_ERR_UNCOR_STATUS, &reg32);
1282 	pci_write_config_dword(pdev, aer + PCI_ERR_UNCOR_STATUS, reg32);
1283 
1284 	/*
1285 	 * Enable error reporting for the root port device and downstream port
1286 	 * devices.
1287 	 */
1288 	set_downstream_devices_error_reporting(pdev, true);
1289 
1290 	/* Enable Root Port's interrupt in response to error messages */
1291 	pci_read_config_dword(pdev, aer + PCI_ERR_ROOT_COMMAND, &reg32);
1292 	reg32 |= ROOT_PORT_INTR_ON_MESG_MASK;
1293 	pci_write_config_dword(pdev, aer + PCI_ERR_ROOT_COMMAND, reg32);
1294 }
1295 
1296 /**
1297  * aer_disable_rootport - disable Root Port's interrupts when receiving messages
1298  * @rpc: pointer to a Root Port data structure
1299  *
1300  * Invoked when PCIe bus unloads AER service driver.
1301  */
1302 static void aer_disable_rootport(struct aer_rpc *rpc)
1303 {
1304 	struct pci_dev *pdev = rpc->rpd;
1305 	int aer = pdev->aer_cap;
1306 	u32 reg32;
1307 
1308 	/*
1309 	 * Disable error reporting for the root port device and downstream port
1310 	 * devices.
1311 	 */
1312 	set_downstream_devices_error_reporting(pdev, false);
1313 
1314 	/* Disable Root's interrupt in response to error messages */
1315 	pci_read_config_dword(pdev, aer + PCI_ERR_ROOT_COMMAND, &reg32);
1316 	reg32 &= ~ROOT_PORT_INTR_ON_MESG_MASK;
1317 	pci_write_config_dword(pdev, aer + PCI_ERR_ROOT_COMMAND, reg32);
1318 
1319 	/* Clear Root's error status reg */
1320 	pci_read_config_dword(pdev, aer + PCI_ERR_ROOT_STATUS, &reg32);
1321 	pci_write_config_dword(pdev, aer + PCI_ERR_ROOT_STATUS, reg32);
1322 }
1323 
1324 /**
1325  * aer_remove - clean up resources
1326  * @dev: pointer to the pcie_dev data structure
1327  *
1328  * Invoked when PCI Express bus unloads or AER probe fails.
1329  */
1330 static void aer_remove(struct pcie_device *dev)
1331 {
1332 	struct aer_rpc *rpc = get_service_data(dev);
1333 
1334 	aer_disable_rootport(rpc);
1335 }
1336 
1337 /**
1338  * aer_probe - initialize resources
1339  * @dev: pointer to the pcie_dev data structure
1340  *
1341  * Invoked when PCI Express bus loads AER service driver.
1342  */
1343 static int aer_probe(struct pcie_device *dev)
1344 {
1345 	int status;
1346 	struct aer_rpc *rpc;
1347 	struct device *device = &dev->device;
1348 	struct pci_dev *port = dev->port;
1349 
1350 	/* Limit to Root Ports or Root Complex Event Collectors */
1351 	if ((pci_pcie_type(port) != PCI_EXP_TYPE_RC_EC) &&
1352 	    (pci_pcie_type(port) != PCI_EXP_TYPE_ROOT_PORT))
1353 		return -ENODEV;
1354 
1355 	rpc = devm_kzalloc(device, sizeof(struct aer_rpc), GFP_KERNEL);
1356 	if (!rpc)
1357 		return -ENOMEM;
1358 
1359 	rpc->rpd = port;
1360 	INIT_KFIFO(rpc->aer_fifo);
1361 	set_service_data(dev, rpc);
1362 
1363 	status = devm_request_threaded_irq(device, dev->irq, aer_irq, aer_isr,
1364 					   IRQF_SHARED, "aerdrv", dev);
1365 	if (status) {
1366 		pci_err(port, "request AER IRQ %d failed\n", dev->irq);
1367 		return status;
1368 	}
1369 
1370 	aer_enable_rootport(rpc);
1371 	pci_info(port, "enabled with IRQ %d\n", dev->irq);
1372 	return 0;
1373 }
1374 
1375 /**
1376  * aer_root_reset - reset Root Port hierarchy, RCEC, or RCiEP
1377  * @dev: pointer to Root Port, RCEC, or RCiEP
1378  *
1379  * Invoked by Port Bus driver when performing reset.
1380  */
1381 static pci_ers_result_t aer_root_reset(struct pci_dev *dev)
1382 {
1383 	int type = pci_pcie_type(dev);
1384 	struct pci_dev *root;
1385 	int aer;
1386 	struct pci_host_bridge *host = pci_find_host_bridge(dev->bus);
1387 	u32 reg32;
1388 	int rc;
1389 
1390 	/*
1391 	 * Only Root Ports and RCECs have AER Root Command and Root Status
1392 	 * registers.  If "dev" is an RCiEP, the relevant registers are in
1393 	 * the RCEC.
1394 	 */
1395 	if (type == PCI_EXP_TYPE_RC_END)
1396 		root = dev->rcec;
1397 	else
1398 		root = pcie_find_root_port(dev);
1399 
1400 	/*
1401 	 * If the platform retained control of AER, an RCiEP may not have
1402 	 * an RCEC visible to us, so dev->rcec ("root") may be NULL.  In
1403 	 * that case, firmware is responsible for these registers.
1404 	 */
1405 	aer = root ? root->aer_cap : 0;
1406 
1407 	if ((host->native_aer || pcie_ports_native) && aer) {
1408 		/* Disable Root's interrupt in response to error messages */
1409 		pci_read_config_dword(root, aer + PCI_ERR_ROOT_COMMAND, &reg32);
1410 		reg32 &= ~ROOT_PORT_INTR_ON_MESG_MASK;
1411 		pci_write_config_dword(root, aer + PCI_ERR_ROOT_COMMAND, reg32);
1412 	}
1413 
1414 	if (type == PCI_EXP_TYPE_RC_EC || type == PCI_EXP_TYPE_RC_END) {
1415 		rc = pcie_reset_flr(dev, PCI_RESET_DO_RESET);
1416 		if (!rc)
1417 			pci_info(dev, "has been reset\n");
1418 		else
1419 			pci_info(dev, "not reset (no FLR support: %d)\n", rc);
1420 	} else {
1421 		rc = pci_bus_error_reset(dev);
1422 		pci_info(dev, "%s Port link has been reset (%d)\n",
1423 			pci_is_root_bus(dev->bus) ? "Root" : "Downstream", rc);
1424 	}
1425 
1426 	if ((host->native_aer || pcie_ports_native) && aer) {
1427 		/* Clear Root Error Status */
1428 		pci_read_config_dword(root, aer + PCI_ERR_ROOT_STATUS, &reg32);
1429 		pci_write_config_dword(root, aer + PCI_ERR_ROOT_STATUS, reg32);
1430 
1431 		/* Enable Root Port's interrupt in response to error messages */
1432 		pci_read_config_dword(root, aer + PCI_ERR_ROOT_COMMAND, &reg32);
1433 		reg32 |= ROOT_PORT_INTR_ON_MESG_MASK;
1434 		pci_write_config_dword(root, aer + PCI_ERR_ROOT_COMMAND, reg32);
1435 	}
1436 
1437 	return rc ? PCI_ERS_RESULT_DISCONNECT : PCI_ERS_RESULT_RECOVERED;
1438 }
1439 
1440 static struct pcie_port_service_driver aerdriver = {
1441 	.name		= "aer",
1442 	.port_type	= PCIE_ANY_PORT,
1443 	.service	= PCIE_PORT_SERVICE_AER,
1444 
1445 	.probe		= aer_probe,
1446 	.remove		= aer_remove,
1447 };
1448 
1449 /**
1450  * pcie_aer_init - register AER root service driver
1451  *
1452  * Invoked when AER root service driver is loaded.
1453  */
1454 int __init pcie_aer_init(void)
1455 {
1456 	if (!pci_aer_available())
1457 		return -ENXIO;
1458 	return pcie_port_service_register(&aerdriver);
1459 }
1460