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