2 * drivers/pci/pcie/aer/aerdrv_core.c
4 * This file is subject to the terms and conditions of the GNU General Public
5 * License. See the file "COPYING" in the main directory of this archive
8 * This file implements the core part of PCI-Express AER. When an pci-express
9 * error is delivered, an error message will be collected and printed to
10 * console, then, an error recovery procedure will be executed by following
11 * the pci error recovery rules.
13 * Copyright (C) 2006 Intel Corp.
14 * Tom Long Nguyen (tom.l.nguyen@intel.com)
15 * Zhang Yanmin (yanmin.zhang@intel.com)
19 #include <linux/module.h>
20 #include <linux/pci.h>
21 #include <linux/kernel.h>
22 #include <linux/errno.h>
24 #include <linux/suspend.h>
25 #include <linux/delay.h>
29 module_param(forceload
, bool, 0);
31 #define PCI_CFG_SPACE_SIZE (0x100)
32 int pci_find_aer_capability(struct pci_dev
*dev
)
37 /* Check if it's a pci-express device */
38 pos
= pci_find_capability(dev
, PCI_CAP_ID_EXP
);
42 /* Check if it supports pci-express AER */
43 pos
= PCI_CFG_SPACE_SIZE
;
45 if (pci_read_config_dword(dev
, pos
, ®32
))
48 /* some broken boards return ~0 */
49 if (reg32
== 0xffffffff)
52 if (PCI_EXT_CAP_ID(reg32
) == PCI_EXT_CAP_ID_ERR
)
61 int pci_enable_pcie_error_reporting(struct pci_dev
*dev
)
66 pos
= pci_find_capability(dev
, PCI_CAP_ID_EXP
);
70 pci_read_config_word(dev
, pos
+PCI_EXP_DEVCTL
, ®16
);
73 PCI_EXP_DEVCTL_NFERE
|
76 pci_write_config_word(dev
, pos
+PCI_EXP_DEVCTL
,
81 int pci_disable_pcie_error_reporting(struct pci_dev
*dev
)
86 pos
= pci_find_capability(dev
, PCI_CAP_ID_EXP
);
90 pci_read_config_word(dev
, pos
+PCI_EXP_DEVCTL
, ®16
);
91 reg16
= reg16
& ~(PCI_EXP_DEVCTL_CERE
|
92 PCI_EXP_DEVCTL_NFERE
|
95 pci_write_config_word(dev
, pos
+PCI_EXP_DEVCTL
,
100 int pci_cleanup_aer_uncorrect_error_status(struct pci_dev
*dev
)
105 pos
= pci_find_aer_capability(dev
);
109 pci_read_config_dword(dev
, pos
+ PCI_ERR_UNCOR_STATUS
, &status
);
110 pci_read_config_dword(dev
, pos
+ PCI_ERR_UNCOR_SEVER
, &mask
);
111 if (dev
->error_state
== pci_channel_io_normal
)
112 status
&= ~mask
; /* Clear corresponding nonfatal bits */
114 status
&= mask
; /* Clear corresponding fatal bits */
115 pci_write_config_dword(dev
, pos
+ PCI_ERR_UNCOR_STATUS
, status
);
120 int pci_cleanup_aer_correct_error_status(struct pci_dev
*dev
)
125 pos
= pci_find_aer_capability(dev
);
129 pci_read_config_dword(dev
, pos
+ PCI_ERR_COR_STATUS
, &status
);
130 pci_write_config_dword(dev
, pos
+ PCI_ERR_COR_STATUS
, status
);
135 static int find_device_iter(struct device
*device
, void *data
)
138 u16 id
= *(unsigned long *)data
;
139 u8 secondary
, subordinate
, d_bus
= id
>> 8;
141 if (device
->bus
== &pci_bus_type
) {
142 dev
= to_pci_dev(device
);
143 if (id
== ((dev
->bus
->number
<< 8) | dev
->devfn
)) {
147 *(unsigned long*)data
= (unsigned long)device
;
152 * If device is P2P, check if it is an upstream?
154 if (dev
->hdr_type
& PCI_HEADER_TYPE_BRIDGE
) {
155 pci_read_config_byte(dev
, PCI_SECONDARY_BUS
,
157 pci_read_config_byte(dev
, PCI_SUBORDINATE_BUS
,
159 if (d_bus
>= secondary
&& d_bus
<= subordinate
) {
160 *(unsigned long*)data
= (unsigned long)device
;
170 * find_source_device - search through device hierarchy for source device
171 * @p_dev: pointer to Root Port pci_dev data structure
172 * @id: device ID of agent who sends an error message to this Root Port
174 * Invoked when error is detected at the Root Port.
176 static struct device
* find_source_device(struct pci_dev
*parent
, u16 id
)
178 struct pci_dev
*dev
= parent
;
179 struct device
*device
;
180 unsigned long device_addr
;
183 /* Is Root Port an agent that sends error message? */
184 if (id
== ((dev
->bus
->number
<< 8) | dev
->devfn
))
189 if ((status
= device_for_each_child(&dev
->dev
,
190 &device_addr
, find_device_iter
))) {
191 device
= (struct device
*)device_addr
;
192 dev
= to_pci_dev(device
);
193 if (id
== ((dev
->bus
->number
<< 8) | dev
->devfn
))
201 static void report_error_detected(struct pci_dev
*dev
, void *data
)
203 pci_ers_result_t vote
;
204 struct pci_error_handlers
*err_handler
;
205 struct aer_broadcast_data
*result_data
;
206 result_data
= (struct aer_broadcast_data
*) data
;
208 dev
->error_state
= result_data
->state
;
211 !dev
->driver
->err_handler
||
212 !dev
->driver
->err_handler
->error_detected
) {
213 if (result_data
->state
== pci_channel_io_frozen
&&
214 !(dev
->hdr_type
& PCI_HEADER_TYPE_BRIDGE
)) {
216 * In case of fatal recovery, if one of down-
217 * stream device has no driver. We might be
218 * unable to recover because a later insmod
219 * of a driver for this device is unaware of
222 printk(KERN_DEBUG
"Device ID[%s] has %s\n",
223 dev
->dev
.bus_id
, (dev
->driver
) ?
224 "no AER-aware driver" : "no driver");
229 err_handler
= dev
->driver
->err_handler
;
230 vote
= err_handler
->error_detected(dev
, result_data
->state
);
231 result_data
->result
= merge_result(result_data
->result
, vote
);
235 static void report_mmio_enabled(struct pci_dev
*dev
, void *data
)
237 pci_ers_result_t vote
;
238 struct pci_error_handlers
*err_handler
;
239 struct aer_broadcast_data
*result_data
;
240 result_data
= (struct aer_broadcast_data
*) data
;
243 !dev
->driver
->err_handler
||
244 !dev
->driver
->err_handler
->mmio_enabled
)
247 err_handler
= dev
->driver
->err_handler
;
248 vote
= err_handler
->mmio_enabled(dev
);
249 result_data
->result
= merge_result(result_data
->result
, vote
);
253 static void report_slot_reset(struct pci_dev
*dev
, void *data
)
255 pci_ers_result_t vote
;
256 struct pci_error_handlers
*err_handler
;
257 struct aer_broadcast_data
*result_data
;
258 result_data
= (struct aer_broadcast_data
*) data
;
261 !dev
->driver
->err_handler
||
262 !dev
->driver
->err_handler
->slot_reset
)
265 err_handler
= dev
->driver
->err_handler
;
266 vote
= err_handler
->slot_reset(dev
);
267 result_data
->result
= merge_result(result_data
->result
, vote
);
271 static void report_resume(struct pci_dev
*dev
, void *data
)
273 struct pci_error_handlers
*err_handler
;
275 dev
->error_state
= pci_channel_io_normal
;
278 !dev
->driver
->err_handler
||
279 !dev
->driver
->err_handler
->slot_reset
)
282 err_handler
= dev
->driver
->err_handler
;
283 err_handler
->resume(dev
);
288 * broadcast_error_message - handle message broadcast to downstream drivers
289 * @device: pointer to from where in a hierarchy message is broadcasted down
290 * @api: callback to be broadcasted
291 * @state: error state
293 * Invoked during error recovery process. Once being invoked, the content
294 * of error severity will be broadcasted to all downstream drivers in a
295 * hierarchy in question.
297 static pci_ers_result_t
broadcast_error_message(struct pci_dev
*dev
,
298 enum pci_channel_state state
,
300 void (*cb
)(struct pci_dev
*, void *))
302 struct aer_broadcast_data result_data
;
304 printk(KERN_DEBUG
"Broadcast %s message\n", error_mesg
);
305 result_data
.state
= state
;
306 if (cb
== report_error_detected
)
307 result_data
.result
= PCI_ERS_RESULT_CAN_RECOVER
;
309 result_data
.result
= PCI_ERS_RESULT_RECOVERED
;
311 if (dev
->hdr_type
& PCI_HEADER_TYPE_BRIDGE
) {
313 * If the error is reported by a bridge, we think this error
314 * is related to the downstream link of the bridge, so we
315 * do error recovery on all subordinates of the bridge instead
316 * of the bridge and clear the error status of the bridge.
318 if (cb
== report_error_detected
)
319 dev
->error_state
= state
;
320 pci_walk_bus(dev
->subordinate
, cb
, &result_data
);
321 if (cb
== report_resume
) {
322 pci_cleanup_aer_uncorrect_error_status(dev
);
323 dev
->error_state
= pci_channel_io_normal
;
328 * If the error is reported by an end point, we think this
329 * error is related to the upstream link of the end point.
331 pci_walk_bus(dev
->bus
, cb
, &result_data
);
334 return result_data
.result
;
337 struct find_aer_service_data
{
338 struct pcie_port_service_driver
*aer_driver
;
342 static int find_aer_service_iter(struct device
*device
, void *data
)
344 struct device_driver
*driver
;
345 struct pcie_port_service_driver
*service_driver
;
346 struct pcie_device
*pcie_dev
;
347 struct find_aer_service_data
*result
;
349 result
= (struct find_aer_service_data
*) data
;
351 if (device
->bus
== &pcie_port_bus_type
) {
352 pcie_dev
= to_pcie_device(device
);
353 if (pcie_dev
->id
.port_type
== PCIE_SW_DOWNSTREAM_PORT
)
354 result
->is_downstream
= 1;
356 driver
= device
->driver
;
358 service_driver
= to_service_driver(driver
);
359 if (service_driver
->id_table
->service_type
==
360 PCIE_PORT_SERVICE_AER
) {
361 result
->aer_driver
= service_driver
;
370 static void find_aer_service(struct pci_dev
*dev
,
371 struct find_aer_service_data
*data
)
374 retval
= device_for_each_child(&dev
->dev
, data
, find_aer_service_iter
);
377 static pci_ers_result_t
reset_link(struct pcie_device
*aerdev
,
380 struct pci_dev
*udev
;
381 pci_ers_result_t status
;
382 struct find_aer_service_data data
;
384 if (dev
->hdr_type
& PCI_HEADER_TYPE_BRIDGE
)
387 udev
= dev
->bus
->self
;
389 data
.is_downstream
= 0;
390 data
.aer_driver
= NULL
;
391 find_aer_service(udev
, &data
);
394 * Use the aer driver of the error agent firstly.
395 * If it hasn't the aer driver, use the root port's
397 if (!data
.aer_driver
|| !data
.aer_driver
->reset_link
) {
398 if (data
.is_downstream
&&
399 aerdev
->device
.driver
&&
400 to_service_driver(aerdev
->device
.driver
)->reset_link
) {
402 to_service_driver(aerdev
->device
.driver
);
404 printk(KERN_DEBUG
"No link-reset support to Device ID"
407 return PCI_ERS_RESULT_DISCONNECT
;
411 status
= data
.aer_driver
->reset_link(udev
);
412 if (status
!= PCI_ERS_RESULT_RECOVERED
) {
413 printk(KERN_DEBUG
"Link reset at upstream Device ID"
416 return PCI_ERS_RESULT_DISCONNECT
;
423 * do_recovery - handle nonfatal/fatal error recovery process
424 * @aerdev: pointer to a pcie_device data structure of root port
425 * @dev: pointer to a pci_dev data structure of agent detecting an error
426 * @severity: error severity type
428 * Invoked when an error is nonfatal/fatal. Once being invoked, broadcast
429 * error detected message to all downstream drivers within a hierarchy in
430 * question and return the returned code.
432 static pci_ers_result_t
do_recovery(struct pcie_device
*aerdev
,
436 pci_ers_result_t status
, result
= PCI_ERS_RESULT_RECOVERED
;
437 enum pci_channel_state state
;
439 if (severity
== AER_FATAL
)
440 state
= pci_channel_io_frozen
;
442 state
= pci_channel_io_normal
;
444 status
= broadcast_error_message(dev
,
447 report_error_detected
);
449 if (severity
== AER_FATAL
) {
450 result
= reset_link(aerdev
, dev
);
451 if (result
!= PCI_ERS_RESULT_RECOVERED
) {
452 /* TODO: Should panic here? */
457 if (status
== PCI_ERS_RESULT_CAN_RECOVER
)
458 status
= broadcast_error_message(dev
,
461 report_mmio_enabled
);
463 if (status
== PCI_ERS_RESULT_NEED_RESET
) {
465 * TODO: Should call platform-specific
466 * functions to reset slot before calling
467 * drivers' slot_reset callbacks?
469 status
= broadcast_error_message(dev
,
475 if (status
== PCI_ERS_RESULT_RECOVERED
)
476 broadcast_error_message(dev
,
485 * handle_error_source - handle logging error into an event log
486 * @aerdev: pointer to pcie_device data structure of the root port
487 * @dev: pointer to pci_dev data structure of error source device
488 * @info: comprehensive error information
490 * Invoked when an error being detected by Root Port.
492 static void handle_error_source(struct pcie_device
* aerdev
,
494 struct aer_err_info info
)
496 pci_ers_result_t status
= 0;
499 if (info
.severity
== AER_CORRECTABLE
) {
501 * Correctable error does not need software intevention.
502 * No need to go through error recovery process.
504 pos
= pci_find_aer_capability(dev
);
506 pci_write_config_dword(dev
, pos
+ PCI_ERR_COR_STATUS
,
509 status
= do_recovery(aerdev
, dev
, info
.severity
);
510 if (status
== PCI_ERS_RESULT_RECOVERED
) {
511 printk(KERN_DEBUG
"AER driver successfully recovered\n");
513 /* TODO: Should kernel panic here? */
514 printk(KERN_DEBUG
"AER driver didn't recover\n");
520 * aer_enable_rootport - enable Root Port's interrupts when receiving messages
521 * @rpc: pointer to a Root Port data structure
523 * Invoked when PCIE bus loads AER service driver.
525 void aer_enable_rootport(struct aer_rpc
*rpc
)
527 struct pci_dev
*pdev
= rpc
->rpd
->port
;
532 pos
= pci_find_capability(pdev
, PCI_CAP_ID_EXP
);
533 /* Clear PCIE Capability's Device Status */
534 pci_read_config_word(pdev
, pos
+PCI_EXP_DEVSTA
, ®16
);
535 pci_write_config_word(pdev
, pos
+PCI_EXP_DEVSTA
, reg16
);
537 /* Disable system error generation in response to error messages */
538 pci_read_config_word(pdev
, pos
+ PCI_EXP_RTCTL
, ®16
);
539 reg16
&= ~(SYSTEM_ERROR_INTR_ON_MESG_MASK
);
540 pci_write_config_word(pdev
, pos
+ PCI_EXP_RTCTL
, reg16
);
542 aer_pos
= pci_find_aer_capability(pdev
);
543 /* Clear error status */
544 pci_read_config_dword(pdev
, aer_pos
+ PCI_ERR_ROOT_STATUS
, ®32
);
545 pci_write_config_dword(pdev
, aer_pos
+ PCI_ERR_ROOT_STATUS
, reg32
);
546 pci_read_config_dword(pdev
, aer_pos
+ PCI_ERR_COR_STATUS
, ®32
);
547 pci_write_config_dword(pdev
, aer_pos
+ PCI_ERR_COR_STATUS
, reg32
);
548 pci_read_config_dword(pdev
, aer_pos
+ PCI_ERR_UNCOR_STATUS
, ®32
);
549 pci_write_config_dword(pdev
, aer_pos
+ PCI_ERR_UNCOR_STATUS
, reg32
);
551 /* Enable Root Port device reporting error itself */
552 pci_read_config_word(pdev
, pos
+PCI_EXP_DEVCTL
, ®16
);
554 PCI_EXP_DEVCTL_CERE
|
555 PCI_EXP_DEVCTL_NFERE
|
556 PCI_EXP_DEVCTL_FERE
|
558 pci_write_config_word(pdev
, pos
+PCI_EXP_DEVCTL
,
561 /* Enable Root Port's interrupt in response to error messages */
562 pci_write_config_dword(pdev
,
563 aer_pos
+ PCI_ERR_ROOT_COMMAND
,
564 ROOT_PORT_INTR_ON_MESG_MASK
);
568 * disable_root_aer - disable Root Port's interrupts when receiving messages
569 * @rpc: pointer to a Root Port data structure
571 * Invoked when PCIE bus unloads AER service driver.
573 static void disable_root_aer(struct aer_rpc
*rpc
)
575 struct pci_dev
*pdev
= rpc
->rpd
->port
;
579 pos
= pci_find_aer_capability(pdev
);
580 /* Disable Root's interrupt in response to error messages */
581 pci_write_config_dword(pdev
, pos
+ PCI_ERR_ROOT_COMMAND
, 0);
583 /* Clear Root's error status reg */
584 pci_read_config_dword(pdev
, pos
+ PCI_ERR_ROOT_STATUS
, ®32
);
585 pci_write_config_dword(pdev
, pos
+ PCI_ERR_ROOT_STATUS
, reg32
);
589 * get_e_source - retrieve an error source
590 * @rpc: pointer to the root port which holds an error
592 * Invoked by DPC handler to consume an error.
594 static struct aer_err_source
* get_e_source(struct aer_rpc
*rpc
)
596 struct aer_err_source
*e_source
;
599 /* Lock access to Root error producer/consumer index */
600 spin_lock_irqsave(&rpc
->e_lock
, flags
);
601 if (rpc
->prod_idx
== rpc
->cons_idx
) {
602 spin_unlock_irqrestore(&rpc
->e_lock
, flags
);
605 e_source
= &rpc
->e_sources
[rpc
->cons_idx
];
607 if (rpc
->cons_idx
== AER_ERROR_SOURCES_MAX
)
609 spin_unlock_irqrestore(&rpc
->e_lock
, flags
);
614 static int get_device_error_info(struct pci_dev
*dev
, struct aer_err_info
*info
)
618 pos
= pci_find_aer_capability(dev
);
620 /* The device might not support AER */
624 if (info
->severity
== AER_CORRECTABLE
) {
625 pci_read_config_dword(dev
, pos
+ PCI_ERR_COR_STATUS
,
627 if (!(info
->status
& ERR_CORRECTABLE_ERROR_MASK
))
628 return AER_UNSUCCESS
;
629 } else if (dev
->hdr_type
& PCI_HEADER_TYPE_BRIDGE
||
630 info
->severity
== AER_NONFATAL
) {
632 /* Link is still healthy for IO reads */
633 pci_read_config_dword(dev
, pos
+ PCI_ERR_UNCOR_STATUS
,
635 if (!(info
->status
& ERR_UNCORRECTABLE_ERROR_MASK
))
636 return AER_UNSUCCESS
;
638 if (info
->status
& AER_LOG_TLP_MASKS
) {
639 info
->flags
|= AER_TLP_HEADER_VALID_FLAG
;
640 pci_read_config_dword(dev
,
641 pos
+ PCI_ERR_HEADER_LOG
, &info
->tlp
.dw0
);
642 pci_read_config_dword(dev
,
643 pos
+ PCI_ERR_HEADER_LOG
+ 4, &info
->tlp
.dw1
);
644 pci_read_config_dword(dev
,
645 pos
+ PCI_ERR_HEADER_LOG
+ 8, &info
->tlp
.dw2
);
646 pci_read_config_dword(dev
,
647 pos
+ PCI_ERR_HEADER_LOG
+ 12, &info
->tlp
.dw3
);
655 * aer_isr_one_error - consume an error detected by root port
656 * @p_device: pointer to error root port service device
657 * @e_src: pointer to an error source
659 static void aer_isr_one_error(struct pcie_device
*p_device
,
660 struct aer_err_source
*e_src
)
662 struct device
*s_device
;
663 struct aer_err_info e_info
= {0, 0, 0,};
668 * There is a possibility that both correctable error and
669 * uncorrectable error being logged. Report correctable error first.
671 for (i
= 1; i
& ROOT_ERR_STATUS_MASKS
; i
<<= 2) {
674 if (!(e_src
->status
& i
))
677 /* Init comprehensive error information */
678 if (i
& PCI_ERR_ROOT_COR_RCV
) {
679 id
= ERR_COR_ID(e_src
->id
);
680 e_info
.severity
= AER_CORRECTABLE
;
682 id
= ERR_UNCOR_ID(e_src
->id
);
683 e_info
.severity
= ((e_src
->status
>> 6) & 1);
686 (PCI_ERR_ROOT_MULTI_COR_RCV
|
687 PCI_ERR_ROOT_MULTI_UNCOR_RCV
))
688 e_info
.flags
|= AER_MULTI_ERROR_VALID_FLAG
;
689 if (!(s_device
= find_source_device(p_device
->port
, id
))) {
690 printk(KERN_DEBUG
"%s->can't find device of ID%04x\n",
694 if (get_device_error_info(to_pci_dev(s_device
), &e_info
) ==
696 aer_print_error(to_pci_dev(s_device
), &e_info
);
697 handle_error_source(p_device
,
698 to_pci_dev(s_device
),
705 * aer_isr - consume errors detected by root port
706 * @work: definition of this work item
708 * Invoked, as DPC, when root port records new detected error
710 void aer_isr(struct work_struct
*work
)
712 struct aer_rpc
*rpc
= container_of(work
, struct aer_rpc
, dpc_handler
);
713 struct pcie_device
*p_device
= rpc
->rpd
;
714 struct aer_err_source
*e_src
;
716 mutex_lock(&rpc
->rpc_mutex
);
717 e_src
= get_e_source(rpc
);
719 aer_isr_one_error(p_device
, e_src
);
720 e_src
= get_e_source(rpc
);
722 mutex_unlock(&rpc
->rpc_mutex
);
724 wake_up(&rpc
->wait_release
);
728 * aer_delete_rootport - disable root port aer and delete service data
729 * @rpc: pointer to a root port device being deleted
731 * Invoked when AER service unloaded on a specific Root Port
733 void aer_delete_rootport(struct aer_rpc
*rpc
)
735 /* Disable root port AER itself */
736 disable_root_aer(rpc
);
742 * aer_init - provide AER initialization
743 * @dev: pointer to AER pcie device
745 * Invoked when AER service driver is loaded.
747 int aer_init(struct pcie_device
*dev
)
749 if (aer_osc_setup(dev
) && !forceload
)
755 EXPORT_SYMBOL_GPL(pci_find_aer_capability
);
756 EXPORT_SYMBOL_GPL(pci_enable_pcie_error_reporting
);
757 EXPORT_SYMBOL_GPL(pci_disable_pcie_error_reporting
);
758 EXPORT_SYMBOL_GPL(pci_cleanup_aer_uncorrect_error_status
);
759 EXPORT_SYMBOL_GPL(pci_cleanup_aer_correct_error_status
);