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 <acpi/ghes.h>
33#include <ras/ras_event.h>
34
35#include "../pci.h"
36#include "portdrv.h"
37
38#define AER_ERROR_SOURCES_MAX		128
39
40#define AER_MAX_TYPEOF_COR_ERRS		16	/* as per PCI_ERR_COR_STATUS */
41#define AER_MAX_TYPEOF_UNCOR_ERRS	27	/* as per PCI_ERR_UNCOR_STATUS*/
42
43struct aer_err_source {
44	u32 status;			/* PCI_ERR_ROOT_STATUS */
45	u32 id;				/* PCI_ERR_ROOT_ERR_SRC */
46};
47
48struct aer_rpc {
49	struct pci_dev *rpd;		/* Root Port device */
50	DECLARE_KFIFO(aer_fifo, struct aer_err_source, AER_ERROR_SOURCES_MAX);
51};
52
53/* AER stats for the device */
54struct aer_stats {
55
56	/*
57	 * Fields for all AER capable devices. They indicate the errors
58	 * "as seen by this device". Note that this may mean that if an
59	 * end point is causing problems, the AER counters may increment
60	 * at its link partner (e.g. root port) because the errors will be
61	 * "seen" by the link partner and not the problematic end point
62	 * itself (which may report all counters as 0 as it never saw any
63	 * problems).
64	 */
65	/* Counters for different type of correctable errors */
66	u64 dev_cor_errs[AER_MAX_TYPEOF_COR_ERRS];
67	/* Counters for different type of fatal uncorrectable errors */
68	u64 dev_fatal_errs[AER_MAX_TYPEOF_UNCOR_ERRS];
69	/* Counters for different type of nonfatal uncorrectable errors */
70	u64 dev_nonfatal_errs[AER_MAX_TYPEOF_UNCOR_ERRS];
71	/* Total number of ERR_COR sent by this device */
72	u64 dev_total_cor_errs;
73	/* Total number of ERR_FATAL sent by this device */
74	u64 dev_total_fatal_errs;
75	/* Total number of ERR_NONFATAL sent by this device */
76	u64 dev_total_nonfatal_errs;
77
78	/*
79	 * Fields for Root ports & root complex event collectors only, these
80	 * indicate the total number of ERR_COR, ERR_FATAL, and ERR_NONFATAL
81	 * messages received by the root port / event collector, INCLUDING the
82	 * ones that are generated internally (by the rootport itself)
83	 */
84	u64 rootport_total_cor_errs;
85	u64 rootport_total_fatal_errs;
86	u64 rootport_total_nonfatal_errs;
87};
88
89#define AER_LOG_TLP_MASKS		(PCI_ERR_UNC_POISON_TLP|	\
90					PCI_ERR_UNC_ECRC|		\
91					PCI_ERR_UNC_UNSUP|		\
92					PCI_ERR_UNC_COMP_ABORT|		\
93					PCI_ERR_UNC_UNX_COMP|		\
94					PCI_ERR_UNC_MALF_TLP)
95
96#define SYSTEM_ERROR_INTR_ON_MESG_MASK	(PCI_EXP_RTCTL_SECEE|	\
97					PCI_EXP_RTCTL_SENFEE|	\
98					PCI_EXP_RTCTL_SEFEE)
99#define ROOT_PORT_INTR_ON_MESG_MASK	(PCI_ERR_ROOT_CMD_COR_EN|	\
100					PCI_ERR_ROOT_CMD_NONFATAL_EN|	\
101					PCI_ERR_ROOT_CMD_FATAL_EN)
102#define ERR_COR_ID(d)			(d & 0xffff)
103#define ERR_UNCOR_ID(d)			(d >> 16)
104
105#define AER_ERR_STATUS_MASK		(PCI_ERR_ROOT_UNCOR_RCV |	\
106					PCI_ERR_ROOT_COR_RCV |		\
107					PCI_ERR_ROOT_MULTI_COR_RCV |	\
108					PCI_ERR_ROOT_MULTI_UNCOR_RCV)
109
110static int pcie_aer_disable;
111static pci_ers_result_t aer_root_reset(struct pci_dev *dev);
112
113void pci_no_aer(void)
114{
115	pcie_aer_disable = 1;
116}
117
118bool pci_aer_available(void)
119{
120	return !pcie_aer_disable && pci_msi_enabled();
121}
122
123#ifdef CONFIG_PCIE_ECRC
124
125#define ECRC_POLICY_DEFAULT 0		/* ECRC set by BIOS */
126#define ECRC_POLICY_OFF     1		/* ECRC off for performance */
127#define ECRC_POLICY_ON      2		/* ECRC on for data integrity */
128
129static int ecrc_policy = ECRC_POLICY_DEFAULT;
130
131static const char * const ecrc_policy_str[] = {
132	[ECRC_POLICY_DEFAULT] = "bios",
133	[ECRC_POLICY_OFF] = "off",
134	[ECRC_POLICY_ON] = "on"
135};
136
137/**
138 * enable_ecrc_checking - enable PCIe ECRC checking for a device
139 * @dev: the PCI device
140 *
141 * Returns 0 on success, or negative on failure.
142 */
143static int enable_ecrc_checking(struct pci_dev *dev)
144{
145	int aer = dev->aer_cap;
146	u32 reg32;
147
148	if (!aer)
149		return -ENODEV;
150
151	pci_read_config_dword(dev, aer + PCI_ERR_CAP, &reg32);
152	if (reg32 & PCI_ERR_CAP_ECRC_GENC)
153		reg32 |= PCI_ERR_CAP_ECRC_GENE;
154	if (reg32 & PCI_ERR_CAP_ECRC_CHKC)
155		reg32 |= PCI_ERR_CAP_ECRC_CHKE;
156	pci_write_config_dword(dev, aer + PCI_ERR_CAP, reg32);
157
158	return 0;
159}
160
161/**
162 * disable_ecrc_checking - disables PCIe ECRC checking for a device
163 * @dev: the PCI device
164 *
165 * Returns 0 on success, or negative on failure.
166 */
167static int disable_ecrc_checking(struct pci_dev *dev)
168{
169	int aer = dev->aer_cap;
170	u32 reg32;
171
172	if (!aer)
173		return -ENODEV;
174
175	pci_read_config_dword(dev, aer + PCI_ERR_CAP, &reg32);
176	reg32 &= ~(PCI_ERR_CAP_ECRC_GENE | PCI_ERR_CAP_ECRC_CHKE);
177	pci_write_config_dword(dev, aer + PCI_ERR_CAP, reg32);
178
179	return 0;
180}
181
182/**
183 * pcie_set_ecrc_checking - set/unset PCIe ECRC checking for a device based on global policy
184 * @dev: the PCI device
185 */
186void pcie_set_ecrc_checking(struct pci_dev *dev)
187{
188	if (!pcie_aer_is_native(dev))
189		return;
190
191	switch (ecrc_policy) {
192	case ECRC_POLICY_DEFAULT:
193		return;
194	case ECRC_POLICY_OFF:
195		disable_ecrc_checking(dev);
196		break;
197	case ECRC_POLICY_ON:
198		enable_ecrc_checking(dev);
199		break;
200	default:
201		return;
202	}
203}
204
205/**
206 * pcie_ecrc_get_policy - parse kernel command-line ecrc option
207 * @str: ECRC policy from kernel command line to use
208 */
209void pcie_ecrc_get_policy(char *str)
210{
211	int i;
212
213	i = match_string(ecrc_policy_str, ARRAY_SIZE(ecrc_policy_str), str);
214	if (i < 0)
215		return;
216
217	ecrc_policy = i;
218}
219#endif	/* CONFIG_PCIE_ECRC */
220
221#define	PCI_EXP_AER_FLAGS	(PCI_EXP_DEVCTL_CERE | PCI_EXP_DEVCTL_NFERE | \
222				 PCI_EXP_DEVCTL_FERE | PCI_EXP_DEVCTL_URRE)
223
224int pcie_aer_is_native(struct pci_dev *dev)
225{
226	struct pci_host_bridge *host = pci_find_host_bridge(dev->bus);
227
228	if (!dev->aer_cap)
229		return 0;
230
231	return pcie_ports_native || host->native_aer;
232}
233EXPORT_SYMBOL_NS_GPL(pcie_aer_is_native, CXL);
234
235static int pci_enable_pcie_error_reporting(struct pci_dev *dev)
236{
237	int rc;
238
239	if (!pcie_aer_is_native(dev))
240		return -EIO;
241
242	rc = pcie_capability_set_word(dev, PCI_EXP_DEVCTL, PCI_EXP_AER_FLAGS);
243	return pcibios_err_to_errno(rc);
244}
245
246int pci_aer_clear_nonfatal_status(struct pci_dev *dev)
247{
248	int aer = dev->aer_cap;
249	u32 status, sev;
250
251	if (!pcie_aer_is_native(dev))
252		return -EIO;
253
254	/* Clear status bits for ERR_NONFATAL errors only */
255	pci_read_config_dword(dev, aer + PCI_ERR_UNCOR_STATUS, &status);
256	pci_read_config_dword(dev, aer + PCI_ERR_UNCOR_SEVER, &sev);
257	status &= ~sev;
258	if (status)
259		pci_write_config_dword(dev, aer + PCI_ERR_UNCOR_STATUS, status);
260
261	return 0;
262}
263EXPORT_SYMBOL_GPL(pci_aer_clear_nonfatal_status);
264
265void pci_aer_clear_fatal_status(struct pci_dev *dev)
266{
267	int aer = dev->aer_cap;
268	u32 status, sev;
269
270	if (!pcie_aer_is_native(dev))
271		return;
272
273	/* Clear status bits for ERR_FATAL errors only */
274	pci_read_config_dword(dev, aer + PCI_ERR_UNCOR_STATUS, &status);
275	pci_read_config_dword(dev, aer + PCI_ERR_UNCOR_SEVER, &sev);
276	status &= sev;
277	if (status)
278		pci_write_config_dword(dev, aer + PCI_ERR_UNCOR_STATUS, status);
279}
280
281/**
282 * pci_aer_raw_clear_status - Clear AER error registers.
283 * @dev: the PCI device
284 *
285 * Clearing AER error status registers unconditionally, regardless of
286 * whether they're owned by firmware or the OS.
287 *
288 * Returns 0 on success, or negative on failure.
289 */
290int pci_aer_raw_clear_status(struct pci_dev *dev)
291{
292	int aer = dev->aer_cap;
293	u32 status;
294	int port_type;
295
296	if (!aer)
297		return -EIO;
298
299	port_type = pci_pcie_type(dev);
300	if (port_type == PCI_EXP_TYPE_ROOT_PORT ||
301	    port_type == PCI_EXP_TYPE_RC_EC) {
302		pci_read_config_dword(dev, aer + PCI_ERR_ROOT_STATUS, &status);
303		pci_write_config_dword(dev, aer + PCI_ERR_ROOT_STATUS, status);
304	}
305
306	pci_read_config_dword(dev, aer + PCI_ERR_COR_STATUS, &status);
307	pci_write_config_dword(dev, aer + PCI_ERR_COR_STATUS, status);
308
309	pci_read_config_dword(dev, aer + PCI_ERR_UNCOR_STATUS, &status);
310	pci_write_config_dword(dev, aer + PCI_ERR_UNCOR_STATUS, status);
311
312	return 0;
313}
314
315int pci_aer_clear_status(struct pci_dev *dev)
316{
317	if (!pcie_aer_is_native(dev))
318		return -EIO;
319
320	return pci_aer_raw_clear_status(dev);
321}
322
323void pci_save_aer_state(struct pci_dev *dev)
324{
325	int aer = dev->aer_cap;
326	struct pci_cap_saved_state *save_state;
327	u32 *cap;
328
329	if (!aer)
330		return;
331
332	save_state = pci_find_saved_ext_cap(dev, PCI_EXT_CAP_ID_ERR);
333	if (!save_state)
334		return;
335
336	cap = &save_state->cap.data[0];
337	pci_read_config_dword(dev, aer + PCI_ERR_UNCOR_MASK, cap++);
338	pci_read_config_dword(dev, aer + PCI_ERR_UNCOR_SEVER, cap++);
339	pci_read_config_dword(dev, aer + PCI_ERR_COR_MASK, cap++);
340	pci_read_config_dword(dev, aer + PCI_ERR_CAP, cap++);
341	if (pcie_cap_has_rtctl(dev))
342		pci_read_config_dword(dev, aer + PCI_ERR_ROOT_COMMAND, cap++);
343}
344
345void pci_restore_aer_state(struct pci_dev *dev)
346{
347	int aer = dev->aer_cap;
348	struct pci_cap_saved_state *save_state;
349	u32 *cap;
350
351	if (!aer)
352		return;
353
354	save_state = pci_find_saved_ext_cap(dev, PCI_EXT_CAP_ID_ERR);
355	if (!save_state)
356		return;
357
358	cap = &save_state->cap.data[0];
359	pci_write_config_dword(dev, aer + PCI_ERR_UNCOR_MASK, *cap++);
360	pci_write_config_dword(dev, aer + PCI_ERR_UNCOR_SEVER, *cap++);
361	pci_write_config_dword(dev, aer + PCI_ERR_COR_MASK, *cap++);
362	pci_write_config_dword(dev, aer + PCI_ERR_CAP, *cap++);
363	if (pcie_cap_has_rtctl(dev))
364		pci_write_config_dword(dev, aer + PCI_ERR_ROOT_COMMAND, *cap++);
365}
366
367void pci_aer_init(struct pci_dev *dev)
368{
369	int n;
370
371	dev->aer_cap = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ERR);
372	if (!dev->aer_cap)
373		return;
374
375	dev->aer_stats = kzalloc(sizeof(struct aer_stats), GFP_KERNEL);
376
377	/*
378	 * We save/restore PCI_ERR_UNCOR_MASK, PCI_ERR_UNCOR_SEVER,
379	 * PCI_ERR_COR_MASK, and PCI_ERR_CAP.  Root and Root Complex Event
380	 * Collectors also implement PCI_ERR_ROOT_COMMAND (PCIe r5.0, sec
381	 * 7.8.4).
382	 */
383	n = pcie_cap_has_rtctl(dev) ? 5 : 4;
384	pci_add_ext_cap_save_buffer(dev, PCI_EXT_CAP_ID_ERR, sizeof(u32) * n);
385
386	pci_aer_clear_status(dev);
387
388	if (pci_aer_available())
389		pci_enable_pcie_error_reporting(dev);
390
391	pcie_set_ecrc_checking(dev);
392}
393
394void pci_aer_exit(struct pci_dev *dev)
395{
396	kfree(dev->aer_stats);
397	dev->aer_stats = NULL;
398}
399
400#define AER_AGENT_RECEIVER		0
401#define AER_AGENT_REQUESTER		1
402#define AER_AGENT_COMPLETER		2
403#define AER_AGENT_TRANSMITTER		3
404
405#define AER_AGENT_REQUESTER_MASK(t)	((t == AER_CORRECTABLE) ?	\
406	0 : (PCI_ERR_UNC_COMP_TIME|PCI_ERR_UNC_UNSUP))
407#define AER_AGENT_COMPLETER_MASK(t)	((t == AER_CORRECTABLE) ?	\
408	0 : PCI_ERR_UNC_COMP_ABORT)
409#define AER_AGENT_TRANSMITTER_MASK(t)	((t == AER_CORRECTABLE) ?	\
410	(PCI_ERR_COR_REP_ROLL|PCI_ERR_COR_REP_TIMER) : 0)
411
412#define AER_GET_AGENT(t, e)						\
413	((e & AER_AGENT_COMPLETER_MASK(t)) ? AER_AGENT_COMPLETER :	\
414	(e & AER_AGENT_REQUESTER_MASK(t)) ? AER_AGENT_REQUESTER :	\
415	(e & AER_AGENT_TRANSMITTER_MASK(t)) ? AER_AGENT_TRANSMITTER :	\
416	AER_AGENT_RECEIVER)
417
418#define AER_PHYSICAL_LAYER_ERROR	0
419#define AER_DATA_LINK_LAYER_ERROR	1
420#define AER_TRANSACTION_LAYER_ERROR	2
421
422#define AER_PHYSICAL_LAYER_ERROR_MASK(t) ((t == AER_CORRECTABLE) ?	\
423	PCI_ERR_COR_RCVR : 0)
424#define AER_DATA_LINK_LAYER_ERROR_MASK(t) ((t == AER_CORRECTABLE) ?	\
425	(PCI_ERR_COR_BAD_TLP|						\
426	PCI_ERR_COR_BAD_DLLP|						\
427	PCI_ERR_COR_REP_ROLL|						\
428	PCI_ERR_COR_REP_TIMER) : PCI_ERR_UNC_DLP)
429
430#define AER_GET_LAYER_ERROR(t, e)					\
431	((e & AER_PHYSICAL_LAYER_ERROR_MASK(t)) ? AER_PHYSICAL_LAYER_ERROR : \
432	(e & AER_DATA_LINK_LAYER_ERROR_MASK(t)) ? AER_DATA_LINK_LAYER_ERROR : \
433	AER_TRANSACTION_LAYER_ERROR)
434
435/*
436 * AER error strings
437 */
438static const char * const aer_error_severity_string[] = {
439	"Uncorrectable (Non-Fatal)",
440	"Uncorrectable (Fatal)",
441	"Correctable"
442};
443
444static const char *aer_error_layer[] = {
445	"Physical Layer",
446	"Data Link Layer",
447	"Transaction Layer"
448};
449
450static const char *aer_correctable_error_string[] = {
451	"RxErr",			/* Bit Position 0	*/
452	NULL,
453	NULL,
454	NULL,
455	NULL,
456	NULL,
457	"BadTLP",			/* Bit Position 6	*/
458	"BadDLLP",			/* Bit Position 7	*/
459	"Rollover",			/* Bit Position 8	*/
460	NULL,
461	NULL,
462	NULL,
463	"Timeout",			/* Bit Position 12	*/
464	"NonFatalErr",			/* Bit Position 13	*/
465	"CorrIntErr",			/* Bit Position 14	*/
466	"HeaderOF",			/* Bit Position 15	*/
467	NULL,				/* Bit Position 16	*/
468	NULL,				/* Bit Position 17	*/
469	NULL,				/* Bit Position 18	*/
470	NULL,				/* Bit Position 19	*/
471	NULL,				/* Bit Position 20	*/
472	NULL,				/* Bit Position 21	*/
473	NULL,				/* Bit Position 22	*/
474	NULL,				/* Bit Position 23	*/
475	NULL,				/* Bit Position 24	*/
476	NULL,				/* Bit Position 25	*/
477	NULL,				/* Bit Position 26	*/
478	NULL,				/* Bit Position 27	*/
479	NULL,				/* Bit Position 28	*/
480	NULL,				/* Bit Position 29	*/
481	NULL,				/* Bit Position 30	*/
482	NULL,				/* Bit Position 31	*/
483};
484
485static const char *aer_uncorrectable_error_string[] = {
486	"Undefined",			/* Bit Position 0	*/
487	NULL,
488	NULL,
489	NULL,
490	"DLP",				/* Bit Position 4	*/
491	"SDES",				/* Bit Position 5	*/
492	NULL,
493	NULL,
494	NULL,
495	NULL,
496	NULL,
497	NULL,
498	"TLP",				/* Bit Position 12	*/
499	"FCP",				/* Bit Position 13	*/
500	"CmpltTO",			/* Bit Position 14	*/
501	"CmpltAbrt",			/* Bit Position 15	*/
502	"UnxCmplt",			/* Bit Position 16	*/
503	"RxOF",				/* Bit Position 17	*/
504	"MalfTLP",			/* Bit Position 18	*/
505	"ECRC",				/* Bit Position 19	*/
506	"UnsupReq",			/* Bit Position 20	*/
507	"ACSViol",			/* Bit Position 21	*/
508	"UncorrIntErr",			/* Bit Position 22	*/
509	"BlockedTLP",			/* Bit Position 23	*/
510	"AtomicOpBlocked",		/* Bit Position 24	*/
511	"TLPBlockedErr",		/* Bit Position 25	*/
512	"PoisonTLPBlocked",		/* Bit Position 26	*/
513	NULL,				/* Bit Position 27	*/
514	NULL,				/* Bit Position 28	*/
515	NULL,				/* Bit Position 29	*/
516	NULL,				/* Bit Position 30	*/
517	NULL,				/* Bit Position 31	*/
518};
519
520static const char *aer_agent_string[] = {
521	"Receiver ID",
522	"Requester ID",
523	"Completer ID",
524	"Transmitter ID"
525};
526
527#define aer_stats_dev_attr(name, stats_array, strings_array,		\
528			   total_string, total_field)			\
529	static ssize_t							\
530	name##_show(struct device *dev, struct device_attribute *attr,	\
531		     char *buf)						\
532{									\
533	unsigned int i;							\
534	struct pci_dev *pdev = to_pci_dev(dev);				\
535	u64 *stats = pdev->aer_stats->stats_array;			\
536	size_t len = 0;							\
537									\
538	for (i = 0; i < ARRAY_SIZE(pdev->aer_stats->stats_array); i++) {\
539		if (strings_array[i])					\
540			len += sysfs_emit_at(buf, len, "%s %llu\n",	\
541					     strings_array[i],		\
542					     stats[i]);			\
543		else if (stats[i])					\
544			len += sysfs_emit_at(buf, len,			\
545					     #stats_array "_bit[%d] %llu\n",\
546					     i, stats[i]);		\
547	}								\
548	len += sysfs_emit_at(buf, len, "TOTAL_%s %llu\n", total_string,	\
549			     pdev->aer_stats->total_field);		\
550	return len;							\
551}									\
552static DEVICE_ATTR_RO(name)
553
554aer_stats_dev_attr(aer_dev_correctable, dev_cor_errs,
555		   aer_correctable_error_string, "ERR_COR",
556		   dev_total_cor_errs);
557aer_stats_dev_attr(aer_dev_fatal, dev_fatal_errs,
558		   aer_uncorrectable_error_string, "ERR_FATAL",
559		   dev_total_fatal_errs);
560aer_stats_dev_attr(aer_dev_nonfatal, dev_nonfatal_errs,
561		   aer_uncorrectable_error_string, "ERR_NONFATAL",
562		   dev_total_nonfatal_errs);
563
564#define aer_stats_rootport_attr(name, field)				\
565	static ssize_t							\
566	name##_show(struct device *dev, struct device_attribute *attr,	\
567		     char *buf)						\
568{									\
569	struct pci_dev *pdev = to_pci_dev(dev);				\
570	return sysfs_emit(buf, "%llu\n", pdev->aer_stats->field);	\
571}									\
572static DEVICE_ATTR_RO(name)
573
574aer_stats_rootport_attr(aer_rootport_total_err_cor,
575			 rootport_total_cor_errs);
576aer_stats_rootport_attr(aer_rootport_total_err_fatal,
577			 rootport_total_fatal_errs);
578aer_stats_rootport_attr(aer_rootport_total_err_nonfatal,
579			 rootport_total_nonfatal_errs);
580
581static struct attribute *aer_stats_attrs[] __ro_after_init = {
582	&dev_attr_aer_dev_correctable.attr,
583	&dev_attr_aer_dev_fatal.attr,
584	&dev_attr_aer_dev_nonfatal.attr,
585	&dev_attr_aer_rootport_total_err_cor.attr,
586	&dev_attr_aer_rootport_total_err_fatal.attr,
587	&dev_attr_aer_rootport_total_err_nonfatal.attr,
588	NULL
589};
590
591static umode_t aer_stats_attrs_are_visible(struct kobject *kobj,
592					   struct attribute *a, int n)
593{
594	struct device *dev = kobj_to_dev(kobj);
595	struct pci_dev *pdev = to_pci_dev(dev);
596
597	if (!pdev->aer_stats)
598		return 0;
599
600	if ((a == &dev_attr_aer_rootport_total_err_cor.attr ||
601	     a == &dev_attr_aer_rootport_total_err_fatal.attr ||
602	     a == &dev_attr_aer_rootport_total_err_nonfatal.attr) &&
603	    ((pci_pcie_type(pdev) != PCI_EXP_TYPE_ROOT_PORT) &&
604	     (pci_pcie_type(pdev) != PCI_EXP_TYPE_RC_EC)))
605		return 0;
606
607	return a->mode;
608}
609
610const struct attribute_group aer_stats_attr_group = {
611	.attrs  = aer_stats_attrs,
612	.is_visible = aer_stats_attrs_are_visible,
613};
614
615static void pci_dev_aer_stats_incr(struct pci_dev *pdev,
616				   struct aer_err_info *info)
617{
618	unsigned long status = info->status & ~info->mask;
619	int i, max = -1;
620	u64 *counter = NULL;
621	struct aer_stats *aer_stats = pdev->aer_stats;
622
623	if (!aer_stats)
624		return;
625
626	switch (info->severity) {
627	case AER_CORRECTABLE:
628		aer_stats->dev_total_cor_errs++;
629		counter = &aer_stats->dev_cor_errs[0];
630		max = AER_MAX_TYPEOF_COR_ERRS;
631		break;
632	case AER_NONFATAL:
633		aer_stats->dev_total_nonfatal_errs++;
634		counter = &aer_stats->dev_nonfatal_errs[0];
635		max = AER_MAX_TYPEOF_UNCOR_ERRS;
636		break;
637	case AER_FATAL:
638		aer_stats->dev_total_fatal_errs++;
639		counter = &aer_stats->dev_fatal_errs[0];
640		max = AER_MAX_TYPEOF_UNCOR_ERRS;
641		break;
642	}
643
644	for_each_set_bit(i, &status, max)
645		counter[i]++;
646}
647
648static void pci_rootport_aer_stats_incr(struct pci_dev *pdev,
649				 struct aer_err_source *e_src)
650{
651	struct aer_stats *aer_stats = pdev->aer_stats;
652
653	if (!aer_stats)
654		return;
655
656	if (e_src->status & PCI_ERR_ROOT_COR_RCV)
657		aer_stats->rootport_total_cor_errs++;
658
659	if (e_src->status & PCI_ERR_ROOT_UNCOR_RCV) {
660		if (e_src->status & PCI_ERR_ROOT_FATAL_RCV)
661			aer_stats->rootport_total_fatal_errs++;
662		else
663			aer_stats->rootport_total_nonfatal_errs++;
664	}
665}
666
667static void __print_tlp_header(struct pci_dev *dev, struct pcie_tlp_log *t)
668{
669	pci_err(dev, "  TLP Header: %08x %08x %08x %08x\n",
670		t->dw[0], t->dw[1], t->dw[2], t->dw[3]);
671}
672
673static void __aer_print_error(struct pci_dev *dev,
674			      struct aer_err_info *info)
675{
676	const char **strings;
677	unsigned long status = info->status & ~info->mask;
678	const char *level, *errmsg;
679	int i;
680
681	if (info->severity == AER_CORRECTABLE) {
682		strings = aer_correctable_error_string;
683		level = KERN_WARNING;
684	} else {
685		strings = aer_uncorrectable_error_string;
686		level = KERN_ERR;
687	}
688
689	for_each_set_bit(i, &status, 32) {
690		errmsg = strings[i];
691		if (!errmsg)
692			errmsg = "Unknown Error Bit";
693
694		pci_printk(level, dev, "   [%2d] %-22s%s\n", i, errmsg,
695				info->first_error == i ? " (First)" : "");
696	}
697	pci_dev_aer_stats_incr(dev, info);
698}
699
700void aer_print_error(struct pci_dev *dev, struct aer_err_info *info)
701{
702	int layer, agent;
703	int id = pci_dev_id(dev);
704	const char *level;
705
706	if (!info->status) {
707		pci_err(dev, "PCIe Bus Error: severity=%s, type=Inaccessible, (Unregistered Agent ID)\n",
708			aer_error_severity_string[info->severity]);
709		goto out;
710	}
711
712	layer = AER_GET_LAYER_ERROR(info->severity, info->status);
713	agent = AER_GET_AGENT(info->severity, info->status);
714
715	level = (info->severity == AER_CORRECTABLE) ? KERN_WARNING : KERN_ERR;
716
717	pci_printk(level, dev, "PCIe Bus Error: severity=%s, type=%s, (%s)\n",
718		   aer_error_severity_string[info->severity],
719		   aer_error_layer[layer], aer_agent_string[agent]);
720
721	pci_printk(level, dev, "  device [%04x:%04x] error status/mask=%08x/%08x\n",
722		   dev->vendor, dev->device, info->status, info->mask);
723
724	__aer_print_error(dev, info);
725
726	if (info->tlp_header_valid)
727		__print_tlp_header(dev, &info->tlp);
728
729out:
730	if (info->id && info->error_dev_num > 1 && info->id == id)
731		pci_err(dev, "  Error of this Agent is reported first\n");
732
733	trace_aer_event(dev_name(&dev->dev), (info->status & ~info->mask),
734			info->severity, info->tlp_header_valid, &info->tlp);
735}
736
737static void aer_print_port_info(struct pci_dev *dev, struct aer_err_info *info)
738{
739	u8 bus = info->id >> 8;
740	u8 devfn = info->id & 0xff;
741
742	pci_info(dev, "%s%s error message received from %04x:%02x:%02x.%d\n",
743		 info->multi_error_valid ? "Multiple " : "",
744		 aer_error_severity_string[info->severity],
745		 pci_domain_nr(dev->bus), bus, PCI_SLOT(devfn),
746		 PCI_FUNC(devfn));
747}
748
749#ifdef CONFIG_ACPI_APEI_PCIEAER
750int cper_severity_to_aer(int cper_severity)
751{
752	switch (cper_severity) {
753	case CPER_SEV_RECOVERABLE:
754		return AER_NONFATAL;
755	case CPER_SEV_FATAL:
756		return AER_FATAL;
757	default:
758		return AER_CORRECTABLE;
759	}
760}
761EXPORT_SYMBOL_GPL(cper_severity_to_aer);
762#endif
763
764void pci_print_aer(struct pci_dev *dev, int aer_severity,
765		   struct aer_capability_regs *aer)
766{
767	int layer, agent, tlp_header_valid = 0;
768	u32 status, mask;
769	struct aer_err_info info;
770
771	if (aer_severity == AER_CORRECTABLE) {
772		status = aer->cor_status;
773		mask = aer->cor_mask;
774	} else {
775		status = aer->uncor_status;
776		mask = aer->uncor_mask;
777		tlp_header_valid = status & AER_LOG_TLP_MASKS;
778	}
779
780	layer = AER_GET_LAYER_ERROR(aer_severity, status);
781	agent = AER_GET_AGENT(aer_severity, status);
782
783	memset(&info, 0, sizeof(info));
784	info.severity = aer_severity;
785	info.status = status;
786	info.mask = mask;
787	info.first_error = PCI_ERR_CAP_FEP(aer->cap_control);
788
789	pci_err(dev, "aer_status: 0x%08x, aer_mask: 0x%08x\n", status, mask);
790	__aer_print_error(dev, &info);
791	pci_err(dev, "aer_layer=%s, aer_agent=%s\n",
792		aer_error_layer[layer], aer_agent_string[agent]);
793
794	if (aer_severity != AER_CORRECTABLE)
795		pci_err(dev, "aer_uncor_severity: 0x%08x\n",
796			aer->uncor_severity);
797
798	if (tlp_header_valid)
799		__print_tlp_header(dev, &aer->header_log);
800
801	trace_aer_event(dev_name(&dev->dev), (status & ~mask),
802			aer_severity, tlp_header_valid, &aer->header_log);
803}
804EXPORT_SYMBOL_NS_GPL(pci_print_aer, CXL);
805
806/**
807 * add_error_device - list device to be handled
808 * @e_info: pointer to error info
809 * @dev: pointer to pci_dev to be added
810 */
811static int add_error_device(struct aer_err_info *e_info, struct pci_dev *dev)
812{
813	if (e_info->error_dev_num < AER_MAX_MULTI_ERR_DEVICES) {
814		e_info->dev[e_info->error_dev_num] = pci_dev_get(dev);
815		e_info->error_dev_num++;
816		return 0;
817	}
818	return -ENOSPC;
819}
820
821/**
822 * is_error_source - check whether the device is source of reported error
823 * @dev: pointer to pci_dev to be checked
824 * @e_info: pointer to reported error info
825 */
826static bool is_error_source(struct pci_dev *dev, struct aer_err_info *e_info)
827{
828	int aer = dev->aer_cap;
829	u32 status, mask;
830	u16 reg16;
831
832	/*
833	 * When bus id is equal to 0, it might be a bad id
834	 * reported by root port.
835	 */
836	if ((PCI_BUS_NUM(e_info->id) != 0) &&
837	    !(dev->bus->bus_flags & PCI_BUS_FLAGS_NO_AERSID)) {
838		/* Device ID match? */
839		if (e_info->id == pci_dev_id(dev))
840			return true;
841
842		/* Continue id comparing if there is no multiple error */
843		if (!e_info->multi_error_valid)
844			return false;
845	}
846
847	/*
848	 * When either
849	 *      1) bus id is equal to 0. Some ports might lose the bus
850	 *              id of error source id;
851	 *      2) bus flag PCI_BUS_FLAGS_NO_AERSID is set
852	 *      3) There are multiple errors and prior ID comparing fails;
853	 * We check AER status registers to find possible reporter.
854	 */
855	if (atomic_read(&dev->enable_cnt) == 0)
856		return false;
857
858	/* Check if AER is enabled */
859	pcie_capability_read_word(dev, PCI_EXP_DEVCTL, &reg16);
860	if (!(reg16 & PCI_EXP_AER_FLAGS))
861		return false;
862
863	if (!aer)
864		return false;
865
866	/* Check if error is recorded */
867	if (e_info->severity == AER_CORRECTABLE) {
868		pci_read_config_dword(dev, aer + PCI_ERR_COR_STATUS, &status);
869		pci_read_config_dword(dev, aer + PCI_ERR_COR_MASK, &mask);
870	} else {
871		pci_read_config_dword(dev, aer + PCI_ERR_UNCOR_STATUS, &status);
872		pci_read_config_dword(dev, aer + PCI_ERR_UNCOR_MASK, &mask);
873	}
874	if (status & ~mask)
875		return true;
876
877	return false;
878}
879
880static int find_device_iter(struct pci_dev *dev, void *data)
881{
882	struct aer_err_info *e_info = (struct aer_err_info *)data;
883
884	if (is_error_source(dev, e_info)) {
885		/* List this device */
886		if (add_error_device(e_info, dev)) {
887			/* We cannot handle more... Stop iteration */
888			/* TODO: Should print error message here? */
889			return 1;
890		}
891
892		/* If there is only a single error, stop iteration */
893		if (!e_info->multi_error_valid)
894			return 1;
895	}
896	return 0;
897}
898
899/**
900 * find_source_device - search through device hierarchy for source device
901 * @parent: pointer to Root Port pci_dev data structure
902 * @e_info: including detailed error information such like id
903 *
904 * Return true if found.
905 *
906 * Invoked by DPC when error is detected at the Root Port.
907 * Caller of this function must set id, severity, and multi_error_valid of
908 * struct aer_err_info pointed by @e_info properly.  This function must fill
909 * e_info->error_dev_num and e_info->dev[], based on the given information.
910 */
911static bool find_source_device(struct pci_dev *parent,
912		struct aer_err_info *e_info)
913{
914	struct pci_dev *dev = parent;
915	int result;
916
917	/* Must reset in this function */
918	e_info->error_dev_num = 0;
919
920	/* Is Root Port an agent that sends error message? */
921	result = find_device_iter(dev, e_info);
922	if (result)
923		return true;
924
925	if (pci_pcie_type(parent) == PCI_EXP_TYPE_RC_EC)
926		pcie_walk_rcec(parent, find_device_iter, e_info);
927	else
928		pci_walk_bus(parent->subordinate, find_device_iter, e_info);
929
930	if (!e_info->error_dev_num) {
931		u8 bus = e_info->id >> 8;
932		u8 devfn = e_info->id & 0xff;
933
934		pci_info(parent, "found no error details for %04x:%02x:%02x.%d\n",
935			 pci_domain_nr(parent->bus), bus, PCI_SLOT(devfn),
936			 PCI_FUNC(devfn));
937		return false;
938	}
939	return true;
940}
941
942#ifdef CONFIG_PCIEAER_CXL
943
944/**
945 * pci_aer_unmask_internal_errors - unmask internal errors
946 * @dev: pointer to the pcie_dev data structure
947 *
948 * Unmasks internal errors in the Uncorrectable and Correctable Error
949 * Mask registers.
950 *
951 * Note: AER must be enabled and supported by the device which must be
952 * checked in advance, e.g. with pcie_aer_is_native().
953 */
954static void pci_aer_unmask_internal_errors(struct pci_dev *dev)
955{
956	int aer = dev->aer_cap;
957	u32 mask;
958
959	pci_read_config_dword(dev, aer + PCI_ERR_UNCOR_MASK, &mask);
960	mask &= ~PCI_ERR_UNC_INTN;
961	pci_write_config_dword(dev, aer + PCI_ERR_UNCOR_MASK, mask);
962
963	pci_read_config_dword(dev, aer + PCI_ERR_COR_MASK, &mask);
964	mask &= ~PCI_ERR_COR_INTERNAL;
965	pci_write_config_dword(dev, aer + PCI_ERR_COR_MASK, mask);
966}
967
968static bool is_cxl_mem_dev(struct pci_dev *dev)
969{
970	/*
971	 * The capability, status, and control fields in Device 0,
972	 * Function 0 DVSEC control the CXL functionality of the
973	 * entire device (CXL 3.0, 8.1.3).
974	 */
975	if (dev->devfn != PCI_DEVFN(0, 0))
976		return false;
977
978	/*
979	 * CXL Memory Devices must have the 502h class code set (CXL
980	 * 3.0, 8.1.12.1).
981	 */
982	if ((dev->class >> 8) != PCI_CLASS_MEMORY_CXL)
983		return false;
984
985	return true;
986}
987
988static bool cxl_error_is_native(struct pci_dev *dev)
989{
990	struct pci_host_bridge *host = pci_find_host_bridge(dev->bus);
991
992	return (pcie_ports_native || host->native_aer);
993}
994
995static bool is_internal_error(struct aer_err_info *info)
996{
997	if (info->severity == AER_CORRECTABLE)
998		return info->status & PCI_ERR_COR_INTERNAL;
999
1000	return info->status & PCI_ERR_UNC_INTN;
1001}
1002
1003static int cxl_rch_handle_error_iter(struct pci_dev *dev, void *data)
1004{
1005	struct aer_err_info *info = (struct aer_err_info *)data;
1006	const struct pci_error_handlers *err_handler;
1007
1008	if (!is_cxl_mem_dev(dev) || !cxl_error_is_native(dev))
1009		return 0;
1010
1011	/* protect dev->driver */
1012	device_lock(&dev->dev);
1013
1014	err_handler = dev->driver ? dev->driver->err_handler : NULL;
1015	if (!err_handler)
1016		goto out;
1017
1018	if (info->severity == AER_CORRECTABLE) {
1019		if (err_handler->cor_error_detected)
1020			err_handler->cor_error_detected(dev);
1021	} else if (err_handler->error_detected) {
1022		if (info->severity == AER_NONFATAL)
1023			err_handler->error_detected(dev, pci_channel_io_normal);
1024		else if (info->severity == AER_FATAL)
1025			err_handler->error_detected(dev, pci_channel_io_frozen);
1026	}
1027out:
1028	device_unlock(&dev->dev);
1029	return 0;
1030}
1031
1032static void cxl_rch_handle_error(struct pci_dev *dev, struct aer_err_info *info)
1033{
1034	/*
1035	 * Internal errors of an RCEC indicate an AER error in an
1036	 * RCH's downstream port. Check and handle them in the CXL.mem
1037	 * device driver.
1038	 */
1039	if (pci_pcie_type(dev) == PCI_EXP_TYPE_RC_EC &&
1040	    is_internal_error(info))
1041		pcie_walk_rcec(dev, cxl_rch_handle_error_iter, info);
1042}
1043
1044static int handles_cxl_error_iter(struct pci_dev *dev, void *data)
1045{
1046	bool *handles_cxl = data;
1047
1048	if (!*handles_cxl)
1049		*handles_cxl = is_cxl_mem_dev(dev) && cxl_error_is_native(dev);
1050
1051	/* Non-zero terminates iteration */
1052	return *handles_cxl;
1053}
1054
1055static bool handles_cxl_errors(struct pci_dev *rcec)
1056{
1057	bool handles_cxl = false;
1058
1059	if (pci_pcie_type(rcec) == PCI_EXP_TYPE_RC_EC &&
1060	    pcie_aer_is_native(rcec))
1061		pcie_walk_rcec(rcec, handles_cxl_error_iter, &handles_cxl);
1062
1063	return handles_cxl;
1064}
1065
1066static void cxl_rch_enable_rcec(struct pci_dev *rcec)
1067{
1068	if (!handles_cxl_errors(rcec))
1069		return;
1070
1071	pci_aer_unmask_internal_errors(rcec);
1072	pci_info(rcec, "CXL: Internal errors unmasked");
1073}
1074
1075#else
1076static inline void cxl_rch_enable_rcec(struct pci_dev *dev) { }
1077static inline void cxl_rch_handle_error(struct pci_dev *dev,
1078					struct aer_err_info *info) { }
1079#endif
1080
1081/**
1082 * pci_aer_handle_error - handle logging error into an event log
1083 * @dev: pointer to pci_dev data structure of error source device
1084 * @info: comprehensive error information
1085 *
1086 * Invoked when an error being detected by Root Port.
1087 */
1088static void pci_aer_handle_error(struct pci_dev *dev, struct aer_err_info *info)
1089{
1090	int aer = dev->aer_cap;
1091
1092	if (info->severity == AER_CORRECTABLE) {
1093		/*
1094		 * Correctable error does not need software intervention.
1095		 * No need to go through error recovery process.
1096		 */
1097		if (aer)
1098			pci_write_config_dword(dev, aer + PCI_ERR_COR_STATUS,
1099					info->status);
1100		if (pcie_aer_is_native(dev)) {
1101			struct pci_driver *pdrv = dev->driver;
1102
1103			if (pdrv && pdrv->err_handler &&
1104			    pdrv->err_handler->cor_error_detected)
1105				pdrv->err_handler->cor_error_detected(dev);
1106			pcie_clear_device_status(dev);
1107		}
1108	} else if (info->severity == AER_NONFATAL)
1109		pcie_do_recovery(dev, pci_channel_io_normal, aer_root_reset);
1110	else if (info->severity == AER_FATAL)
1111		pcie_do_recovery(dev, pci_channel_io_frozen, aer_root_reset);
1112}
1113
1114static void handle_error_source(struct pci_dev *dev, struct aer_err_info *info)
1115{
1116	cxl_rch_handle_error(dev, info);
1117	pci_aer_handle_error(dev, info);
1118	pci_dev_put(dev);
1119}
1120
1121#ifdef CONFIG_ACPI_APEI_PCIEAER
1122
1123#define AER_RECOVER_RING_SIZE		16
1124
1125struct aer_recover_entry {
1126	u8	bus;
1127	u8	devfn;
1128	u16	domain;
1129	int	severity;
1130	struct aer_capability_regs *regs;
1131};
1132
1133static DEFINE_KFIFO(aer_recover_ring, struct aer_recover_entry,
1134		    AER_RECOVER_RING_SIZE);
1135
1136static void aer_recover_work_func(struct work_struct *work)
1137{
1138	struct aer_recover_entry entry;
1139	struct pci_dev *pdev;
1140
1141	while (kfifo_get(&aer_recover_ring, &entry)) {
1142		pdev = pci_get_domain_bus_and_slot(entry.domain, entry.bus,
1143						   entry.devfn);
1144		if (!pdev) {
1145			pr_err("no pci_dev for %04x:%02x:%02x.%x\n",
1146			       entry.domain, entry.bus,
1147			       PCI_SLOT(entry.devfn), PCI_FUNC(entry.devfn));
1148			continue;
1149		}
1150		pci_print_aer(pdev, entry.severity, entry.regs);
1151		/*
1152		 * Memory for aer_capability_regs(entry.regs) is being allocated from the
1153		 * ghes_estatus_pool to protect it from overwriting when multiple sections
1154		 * are present in the error status. Thus free the same after processing
1155		 * the data.
1156		 */
1157		ghes_estatus_pool_region_free((unsigned long)entry.regs,
1158					      sizeof(struct aer_capability_regs));
1159
1160		if (entry.severity == AER_NONFATAL)
1161			pcie_do_recovery(pdev, pci_channel_io_normal,
1162					 aer_root_reset);
1163		else if (entry.severity == AER_FATAL)
1164			pcie_do_recovery(pdev, pci_channel_io_frozen,
1165					 aer_root_reset);
1166		pci_dev_put(pdev);
1167	}
1168}
1169
1170/*
1171 * Mutual exclusion for writers of aer_recover_ring, reader side don't
1172 * need lock, because there is only one reader and lock is not needed
1173 * between reader and writer.
1174 */
1175static DEFINE_SPINLOCK(aer_recover_ring_lock);
1176static DECLARE_WORK(aer_recover_work, aer_recover_work_func);
1177
1178void aer_recover_queue(int domain, unsigned int bus, unsigned int devfn,
1179		       int severity, struct aer_capability_regs *aer_regs)
1180{
1181	struct aer_recover_entry entry = {
1182		.bus		= bus,
1183		.devfn		= devfn,
1184		.domain		= domain,
1185		.severity	= severity,
1186		.regs		= aer_regs,
1187	};
1188
1189	if (kfifo_in_spinlocked(&aer_recover_ring, &entry, 1,
1190				 &aer_recover_ring_lock))
1191		schedule_work(&aer_recover_work);
1192	else
1193		pr_err("buffer overflow in recovery for %04x:%02x:%02x.%x\n",
1194		       domain, bus, PCI_SLOT(devfn), PCI_FUNC(devfn));
1195}
1196EXPORT_SYMBOL_GPL(aer_recover_queue);
1197#endif
1198
1199/**
1200 * aer_get_device_error_info - read error status from dev and store it to info
1201 * @dev: pointer to the device expected to have a error record
1202 * @info: pointer to structure to store the error record
1203 *
1204 * Return 1 on success, 0 on error.
1205 *
1206 * Note that @info is reused among all error devices. Clear fields properly.
1207 */
1208int aer_get_device_error_info(struct pci_dev *dev, struct aer_err_info *info)
1209{
1210	int type = pci_pcie_type(dev);
1211	int aer = dev->aer_cap;
1212	u32 aercc;
1213
1214	/* Must reset in this function */
1215	info->status = 0;
1216	info->tlp_header_valid = 0;
1217
1218	/* The device might not support AER */
1219	if (!aer)
1220		return 0;
1221
1222	if (info->severity == AER_CORRECTABLE) {
1223		pci_read_config_dword(dev, aer + PCI_ERR_COR_STATUS,
1224			&info->status);
1225		pci_read_config_dword(dev, aer + PCI_ERR_COR_MASK,
1226			&info->mask);
1227		if (!(info->status & ~info->mask))
1228			return 0;
1229	} else if (type == PCI_EXP_TYPE_ROOT_PORT ||
1230		   type == PCI_EXP_TYPE_RC_EC ||
1231		   type == PCI_EXP_TYPE_DOWNSTREAM ||
1232		   info->severity == AER_NONFATAL) {
1233
1234		/* Link is still healthy for IO reads */
1235		pci_read_config_dword(dev, aer + PCI_ERR_UNCOR_STATUS,
1236			&info->status);
1237		pci_read_config_dword(dev, aer + PCI_ERR_UNCOR_MASK,
1238			&info->mask);
1239		if (!(info->status & ~info->mask))
1240			return 0;
1241
1242		/* Get First Error Pointer */
1243		pci_read_config_dword(dev, aer + PCI_ERR_CAP, &aercc);
1244		info->first_error = PCI_ERR_CAP_FEP(aercc);
1245
1246		if (info->status & AER_LOG_TLP_MASKS) {
1247			info->tlp_header_valid = 1;
1248			pcie_read_tlp_log(dev, aer + PCI_ERR_HEADER_LOG, &info->tlp);
1249		}
1250	}
1251
1252	return 1;
1253}
1254
1255static inline void aer_process_err_devices(struct aer_err_info *e_info)
1256{
1257	int i;
1258
1259	/* Report all before handle them, not to lost records by reset etc. */
1260	for (i = 0; i < e_info->error_dev_num && e_info->dev[i]; i++) {
1261		if (aer_get_device_error_info(e_info->dev[i], e_info))
1262			aer_print_error(e_info->dev[i], e_info);
1263	}
1264	for (i = 0; i < e_info->error_dev_num && e_info->dev[i]; i++) {
1265		if (aer_get_device_error_info(e_info->dev[i], e_info))
1266			handle_error_source(e_info->dev[i], e_info);
1267	}
1268}
1269
1270/**
1271 * aer_isr_one_error - consume an error detected by root port
1272 * @rpc: pointer to the root port which holds an error
1273 * @e_src: pointer to an error source
1274 */
1275static void aer_isr_one_error(struct aer_rpc *rpc,
1276		struct aer_err_source *e_src)
1277{
1278	struct pci_dev *pdev = rpc->rpd;
1279	struct aer_err_info e_info;
1280
1281	pci_rootport_aer_stats_incr(pdev, e_src);
1282
1283	/*
1284	 * There is a possibility that both correctable error and
1285	 * uncorrectable error being logged. Report correctable error first.
1286	 */
1287	if (e_src->status & PCI_ERR_ROOT_COR_RCV) {
1288		e_info.id = ERR_COR_ID(e_src->id);
1289		e_info.severity = AER_CORRECTABLE;
1290
1291		if (e_src->status & PCI_ERR_ROOT_MULTI_COR_RCV)
1292			e_info.multi_error_valid = 1;
1293		else
1294			e_info.multi_error_valid = 0;
1295		aer_print_port_info(pdev, &e_info);
1296
1297		if (find_source_device(pdev, &e_info))
1298			aer_process_err_devices(&e_info);
1299	}
1300
1301	if (e_src->status & PCI_ERR_ROOT_UNCOR_RCV) {
1302		e_info.id = ERR_UNCOR_ID(e_src->id);
1303
1304		if (e_src->status & PCI_ERR_ROOT_FATAL_RCV)
1305			e_info.severity = AER_FATAL;
1306		else
1307			e_info.severity = AER_NONFATAL;
1308
1309		if (e_src->status & PCI_ERR_ROOT_MULTI_UNCOR_RCV)
1310			e_info.multi_error_valid = 1;
1311		else
1312			e_info.multi_error_valid = 0;
1313
1314		aer_print_port_info(pdev, &e_info);
1315
1316		if (find_source_device(pdev, &e_info))
1317			aer_process_err_devices(&e_info);
1318	}
1319}
1320
1321/**
1322 * aer_isr - consume errors detected by root port
1323 * @irq: IRQ assigned to Root Port
1324 * @context: pointer to Root Port data structure
1325 *
1326 * Invoked, as DPC, when root port records new detected error
1327 */
1328static irqreturn_t aer_isr(int irq, void *context)
1329{
1330	struct pcie_device *dev = (struct pcie_device *)context;
1331	struct aer_rpc *rpc = get_service_data(dev);
1332	struct aer_err_source e_src;
1333
1334	if (kfifo_is_empty(&rpc->aer_fifo))
1335		return IRQ_NONE;
1336
1337	while (kfifo_get(&rpc->aer_fifo, &e_src))
1338		aer_isr_one_error(rpc, &e_src);
1339	return IRQ_HANDLED;
1340}
1341
1342/**
1343 * aer_irq - Root Port's ISR
1344 * @irq: IRQ assigned to Root Port
1345 * @context: pointer to Root Port data structure
1346 *
1347 * Invoked when Root Port detects AER messages.
1348 */
1349static irqreturn_t aer_irq(int irq, void *context)
1350{
1351	struct pcie_device *pdev = (struct pcie_device *)context;
1352	struct aer_rpc *rpc = get_service_data(pdev);
1353	struct pci_dev *rp = rpc->rpd;
1354	int aer = rp->aer_cap;
1355	struct aer_err_source e_src = {};
1356
1357	pci_read_config_dword(rp, aer + PCI_ERR_ROOT_STATUS, &e_src.status);
1358	if (!(e_src.status & AER_ERR_STATUS_MASK))
1359		return IRQ_NONE;
1360
1361	pci_read_config_dword(rp, aer + PCI_ERR_ROOT_ERR_SRC, &e_src.id);
1362	pci_write_config_dword(rp, aer + PCI_ERR_ROOT_STATUS, e_src.status);
1363
1364	if (!kfifo_put(&rpc->aer_fifo, e_src))
1365		return IRQ_HANDLED;
1366
1367	return IRQ_WAKE_THREAD;
1368}
1369
1370static void aer_enable_irq(struct pci_dev *pdev)
1371{
1372	int aer = pdev->aer_cap;
1373	u32 reg32;
1374
1375	/* Enable Root Port's interrupt in response to error messages */
1376	pci_read_config_dword(pdev, aer + PCI_ERR_ROOT_COMMAND, &reg32);
1377	reg32 |= ROOT_PORT_INTR_ON_MESG_MASK;
1378	pci_write_config_dword(pdev, aer + PCI_ERR_ROOT_COMMAND, reg32);
1379}
1380
1381static void aer_disable_irq(struct pci_dev *pdev)
1382{
1383	int aer = pdev->aer_cap;
1384	u32 reg32;
1385
1386	/* Disable Root's interrupt in response to error messages */
1387	pci_read_config_dword(pdev, aer + PCI_ERR_ROOT_COMMAND, &reg32);
1388	reg32 &= ~ROOT_PORT_INTR_ON_MESG_MASK;
1389	pci_write_config_dword(pdev, aer + PCI_ERR_ROOT_COMMAND, reg32);
1390}
1391
1392/**
1393 * aer_enable_rootport - enable Root Port's interrupts when receiving messages
1394 * @rpc: pointer to a Root Port data structure
1395 *
1396 * Invoked when PCIe bus loads AER service driver.
1397 */
1398static void aer_enable_rootport(struct aer_rpc *rpc)
1399{
1400	struct pci_dev *pdev = rpc->rpd;
1401	int aer = pdev->aer_cap;
1402	u16 reg16;
1403	u32 reg32;
1404
1405	/* Clear PCIe Capability's Device Status */
1406	pcie_capability_read_word(pdev, PCI_EXP_DEVSTA, &reg16);
1407	pcie_capability_write_word(pdev, PCI_EXP_DEVSTA, reg16);
1408
1409	/* Disable system error generation in response to error messages */
1410	pcie_capability_clear_word(pdev, PCI_EXP_RTCTL,
1411				   SYSTEM_ERROR_INTR_ON_MESG_MASK);
1412
1413	/* Clear error status */
1414	pci_read_config_dword(pdev, aer + PCI_ERR_ROOT_STATUS, &reg32);
1415	pci_write_config_dword(pdev, aer + PCI_ERR_ROOT_STATUS, reg32);
1416	pci_read_config_dword(pdev, aer + PCI_ERR_COR_STATUS, &reg32);
1417	pci_write_config_dword(pdev, aer + PCI_ERR_COR_STATUS, reg32);
1418	pci_read_config_dword(pdev, aer + PCI_ERR_UNCOR_STATUS, &reg32);
1419	pci_write_config_dword(pdev, aer + PCI_ERR_UNCOR_STATUS, reg32);
1420
1421	aer_enable_irq(pdev);
1422}
1423
1424/**
1425 * aer_disable_rootport - disable Root Port's interrupts when receiving messages
1426 * @rpc: pointer to a Root Port data structure
1427 *
1428 * Invoked when PCIe bus unloads AER service driver.
1429 */
1430static void aer_disable_rootport(struct aer_rpc *rpc)
1431{
1432	struct pci_dev *pdev = rpc->rpd;
1433	int aer = pdev->aer_cap;
1434	u32 reg32;
1435
1436	aer_disable_irq(pdev);
1437
1438	/* Clear Root's error status reg */
1439	pci_read_config_dword(pdev, aer + PCI_ERR_ROOT_STATUS, &reg32);
1440	pci_write_config_dword(pdev, aer + PCI_ERR_ROOT_STATUS, reg32);
1441}
1442
1443/**
1444 * aer_remove - clean up resources
1445 * @dev: pointer to the pcie_dev data structure
1446 *
1447 * Invoked when PCI Express bus unloads or AER probe fails.
1448 */
1449static void aer_remove(struct pcie_device *dev)
1450{
1451	struct aer_rpc *rpc = get_service_data(dev);
1452
1453	aer_disable_rootport(rpc);
1454}
1455
1456/**
1457 * aer_probe - initialize resources
1458 * @dev: pointer to the pcie_dev data structure
1459 *
1460 * Invoked when PCI Express bus loads AER service driver.
1461 */
1462static int aer_probe(struct pcie_device *dev)
1463{
1464	int status;
1465	struct aer_rpc *rpc;
1466	struct device *device = &dev->device;
1467	struct pci_dev *port = dev->port;
1468
1469	BUILD_BUG_ON(ARRAY_SIZE(aer_correctable_error_string) <
1470		     AER_MAX_TYPEOF_COR_ERRS);
1471	BUILD_BUG_ON(ARRAY_SIZE(aer_uncorrectable_error_string) <
1472		     AER_MAX_TYPEOF_UNCOR_ERRS);
1473
1474	/* Limit to Root Ports or Root Complex Event Collectors */
1475	if ((pci_pcie_type(port) != PCI_EXP_TYPE_RC_EC) &&
1476	    (pci_pcie_type(port) != PCI_EXP_TYPE_ROOT_PORT))
1477		return -ENODEV;
1478
1479	rpc = devm_kzalloc(device, sizeof(struct aer_rpc), GFP_KERNEL);
1480	if (!rpc)
1481		return -ENOMEM;
1482
1483	rpc->rpd = port;
1484	INIT_KFIFO(rpc->aer_fifo);
1485	set_service_data(dev, rpc);
1486
1487	status = devm_request_threaded_irq(device, dev->irq, aer_irq, aer_isr,
1488					   IRQF_SHARED, "aerdrv", dev);
1489	if (status) {
1490		pci_err(port, "request AER IRQ %d failed\n", dev->irq);
1491		return status;
1492	}
1493
1494	cxl_rch_enable_rcec(port);
1495	aer_enable_rootport(rpc);
1496	pci_info(port, "enabled with IRQ %d\n", dev->irq);
1497	return 0;
1498}
1499
1500/**
1501 * aer_root_reset - reset Root Port hierarchy, RCEC, or RCiEP
1502 * @dev: pointer to Root Port, RCEC, or RCiEP
1503 *
1504 * Invoked by Port Bus driver when performing reset.
1505 */
1506static pci_ers_result_t aer_root_reset(struct pci_dev *dev)
1507{
1508	int type = pci_pcie_type(dev);
1509	struct pci_dev *root;
1510	int aer;
1511	struct pci_host_bridge *host = pci_find_host_bridge(dev->bus);
1512	u32 reg32;
1513	int rc;
1514
1515	/*
1516	 * Only Root Ports and RCECs have AER Root Command and Root Status
1517	 * registers.  If "dev" is an RCiEP, the relevant registers are in
1518	 * the RCEC.
1519	 */
1520	if (type == PCI_EXP_TYPE_RC_END)
1521		root = dev->rcec;
1522	else
1523		root = pcie_find_root_port(dev);
1524
1525	/*
1526	 * If the platform retained control of AER, an RCiEP may not have
1527	 * an RCEC visible to us, so dev->rcec ("root") may be NULL.  In
1528	 * that case, firmware is responsible for these registers.
1529	 */
1530	aer = root ? root->aer_cap : 0;
1531
1532	if ((host->native_aer || pcie_ports_native) && aer)
1533		aer_disable_irq(root);
1534
1535	if (type == PCI_EXP_TYPE_RC_EC || type == PCI_EXP_TYPE_RC_END) {
1536		rc = pcie_reset_flr(dev, PCI_RESET_DO_RESET);
1537		if (!rc)
1538			pci_info(dev, "has been reset\n");
1539		else
1540			pci_info(dev, "not reset (no FLR support: %d)\n", rc);
1541	} else {
1542		rc = pci_bus_error_reset(dev);
1543		pci_info(dev, "%s Port link has been reset (%d)\n",
1544			pci_is_root_bus(dev->bus) ? "Root" : "Downstream", rc);
1545	}
1546
1547	if ((host->native_aer || pcie_ports_native) && aer) {
1548		/* Clear Root Error Status */
1549		pci_read_config_dword(root, aer + PCI_ERR_ROOT_STATUS, &reg32);
1550		pci_write_config_dword(root, aer + PCI_ERR_ROOT_STATUS, reg32);
1551
1552		aer_enable_irq(root);
1553	}
1554
1555	return rc ? PCI_ERS_RESULT_DISCONNECT : PCI_ERS_RESULT_RECOVERED;
1556}
1557
1558static struct pcie_port_service_driver aerdriver = {
1559	.name		= "aer",
1560	.port_type	= PCIE_ANY_PORT,
1561	.service	= PCIE_PORT_SERVICE_AER,
1562
1563	.probe		= aer_probe,
1564	.remove		= aer_remove,
1565};
1566
1567/**
1568 * pcie_aer_init - register AER root service driver
1569 *
1570 * Invoked when AER root service driver is loaded.
1571 */
1572int __init pcie_aer_init(void)
1573{
1574	if (!pci_aer_available())
1575		return -ENXIO;
1576	return pcie_port_service_register(&aerdriver);
1577}
1578