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 int pci_enable_pcie_error_reporting(struct pci_dev
*dev
)
36 pos
= pci_find_ext_capability(dev
, PCI_EXT_CAP_ID_ERR
);
40 pos
= pci_find_capability(dev
, PCI_CAP_ID_EXP
);
44 pci_read_config_word(dev
, pos
+PCI_EXP_DEVCTL
, ®16
);
47 PCI_EXP_DEVCTL_NFERE
|
50 pci_write_config_word(dev
, pos
+PCI_EXP_DEVCTL
,
55 int pci_disable_pcie_error_reporting(struct pci_dev
*dev
)
60 pos
= pci_find_capability(dev
, PCI_CAP_ID_EXP
);
64 pci_read_config_word(dev
, pos
+PCI_EXP_DEVCTL
, ®16
);
65 reg16
= reg16
& ~(PCI_EXP_DEVCTL_CERE
|
66 PCI_EXP_DEVCTL_NFERE
|
69 pci_write_config_word(dev
, pos
+PCI_EXP_DEVCTL
,
74 int pci_cleanup_aer_uncorrect_error_status(struct pci_dev
*dev
)
79 pos
= pci_find_ext_capability(dev
, PCI_EXT_CAP_ID_ERR
);
83 pci_read_config_dword(dev
, pos
+ PCI_ERR_UNCOR_STATUS
, &status
);
84 pci_read_config_dword(dev
, pos
+ PCI_ERR_UNCOR_SEVER
, &mask
);
85 if (dev
->error_state
== pci_channel_io_normal
)
86 status
&= ~mask
; /* Clear corresponding nonfatal bits */
88 status
&= mask
; /* Clear corresponding fatal bits */
89 pci_write_config_dword(dev
, pos
+ PCI_ERR_UNCOR_STATUS
, status
);
95 int pci_cleanup_aer_correct_error_status(struct pci_dev
*dev
)
100 pos
= pci_find_ext_capability(dev
, PCI_EXT_CAP_ID_ERR
);
104 pci_read_config_dword(dev
, pos
+ PCI_ERR_COR_STATUS
, &status
);
105 pci_write_config_dword(dev
, pos
+ PCI_ERR_COR_STATUS
, status
);
112 static void set_device_error_reporting(struct pci_dev
*dev
, void *data
)
114 bool enable
= *((bool *)data
);
116 if (dev
->pcie_type
!= PCIE_RC_PORT
&&
117 dev
->pcie_type
!= PCIE_SW_UPSTREAM_PORT
&&
118 dev
->pcie_type
!= PCIE_SW_DOWNSTREAM_PORT
)
122 pci_enable_pcie_error_reporting(dev
);
124 pci_disable_pcie_error_reporting(dev
);
128 * set_downstream_devices_error_reporting - enable/disable the error reporting bits on the root port and its downstream ports.
129 * @dev: pointer to root port's pci_dev data structure
130 * @enable: true = enable error reporting, false = disable error reporting.
132 static void set_downstream_devices_error_reporting(struct pci_dev
*dev
,
135 set_device_error_reporting(dev
, &enable
);
137 if (!dev
->subordinate
)
139 pci_walk_bus(dev
->subordinate
, set_device_error_reporting
, &enable
);
142 static int find_device_iter(struct device
*device
, void *data
)
145 u16 id
= *(unsigned long *)data
;
146 u8 secondary
, subordinate
, d_bus
= id
>> 8;
148 if (device
->bus
== &pci_bus_type
) {
149 dev
= to_pci_dev(device
);
150 if (id
== ((dev
->bus
->number
<< 8) | dev
->devfn
)) {
154 *(unsigned long*)data
= (unsigned long)device
;
159 * If device is P2P, check if it is an upstream?
161 if (dev
->hdr_type
& PCI_HEADER_TYPE_BRIDGE
) {
162 pci_read_config_byte(dev
, PCI_SECONDARY_BUS
,
164 pci_read_config_byte(dev
, PCI_SUBORDINATE_BUS
,
166 if (d_bus
>= secondary
&& d_bus
<= subordinate
) {
167 *(unsigned long*)data
= (unsigned long)device
;
177 * find_source_device - search through device hierarchy for source device
178 * @parent: pointer to Root Port pci_dev data structure
179 * @id: device ID of agent who sends an error message to this Root Port
181 * Invoked when error is detected at the Root Port.
183 static struct device
* find_source_device(struct pci_dev
*parent
, u16 id
)
185 struct pci_dev
*dev
= parent
;
186 struct device
*device
;
187 unsigned long device_addr
;
190 /* Is Root Port an agent that sends error message? */
191 if (id
== ((dev
->bus
->number
<< 8) | dev
->devfn
))
196 if ((status
= device_for_each_child(&dev
->dev
,
197 &device_addr
, find_device_iter
))) {
198 device
= (struct device
*)device_addr
;
199 dev
= to_pci_dev(device
);
200 if (id
== ((dev
->bus
->number
<< 8) | dev
->devfn
))
208 static void report_error_detected(struct pci_dev
*dev
, void *data
)
210 pci_ers_result_t vote
;
211 struct pci_error_handlers
*err_handler
;
212 struct aer_broadcast_data
*result_data
;
213 result_data
= (struct aer_broadcast_data
*) data
;
215 dev
->error_state
= result_data
->state
;
218 !dev
->driver
->err_handler
||
219 !dev
->driver
->err_handler
->error_detected
) {
220 if (result_data
->state
== pci_channel_io_frozen
&&
221 !(dev
->hdr_type
& PCI_HEADER_TYPE_BRIDGE
)) {
223 * In case of fatal recovery, if one of down-
224 * stream device has no driver. We might be
225 * unable to recover because a later insmod
226 * of a driver for this device is unaware of
229 dev_printk(KERN_DEBUG
, &dev
->dev
, "device has %s\n",
231 "no AER-aware driver" : "no driver");
236 err_handler
= dev
->driver
->err_handler
;
237 vote
= err_handler
->error_detected(dev
, result_data
->state
);
238 result_data
->result
= merge_result(result_data
->result
, vote
);
242 static void report_mmio_enabled(struct pci_dev
*dev
, void *data
)
244 pci_ers_result_t vote
;
245 struct pci_error_handlers
*err_handler
;
246 struct aer_broadcast_data
*result_data
;
247 result_data
= (struct aer_broadcast_data
*) data
;
250 !dev
->driver
->err_handler
||
251 !dev
->driver
->err_handler
->mmio_enabled
)
254 err_handler
= dev
->driver
->err_handler
;
255 vote
= err_handler
->mmio_enabled(dev
);
256 result_data
->result
= merge_result(result_data
->result
, vote
);
260 static void report_slot_reset(struct pci_dev
*dev
, void *data
)
262 pci_ers_result_t vote
;
263 struct pci_error_handlers
*err_handler
;
264 struct aer_broadcast_data
*result_data
;
265 result_data
= (struct aer_broadcast_data
*) data
;
268 !dev
->driver
->err_handler
||
269 !dev
->driver
->err_handler
->slot_reset
)
272 err_handler
= dev
->driver
->err_handler
;
273 vote
= err_handler
->slot_reset(dev
);
274 result_data
->result
= merge_result(result_data
->result
, vote
);
278 static void report_resume(struct pci_dev
*dev
, void *data
)
280 struct pci_error_handlers
*err_handler
;
282 dev
->error_state
= pci_channel_io_normal
;
285 !dev
->driver
->err_handler
||
286 !dev
->driver
->err_handler
->resume
)
289 err_handler
= dev
->driver
->err_handler
;
290 err_handler
->resume(dev
);
295 * broadcast_error_message - handle message broadcast to downstream drivers
296 * @dev: pointer to from where in a hierarchy message is broadcasted down
297 * @state: error state
298 * @error_mesg: message to print
299 * @cb: callback to be broadcasted
301 * Invoked during error recovery process. Once being invoked, the content
302 * of error severity will be broadcasted to all downstream drivers in a
303 * hierarchy in question.
305 static pci_ers_result_t
broadcast_error_message(struct pci_dev
*dev
,
306 enum pci_channel_state state
,
308 void (*cb
)(struct pci_dev
*, void *))
310 struct aer_broadcast_data result_data
;
312 dev_printk(KERN_DEBUG
, &dev
->dev
, "broadcast %s message\n", error_mesg
);
313 result_data
.state
= state
;
314 if (cb
== report_error_detected
)
315 result_data
.result
= PCI_ERS_RESULT_CAN_RECOVER
;
317 result_data
.result
= PCI_ERS_RESULT_RECOVERED
;
319 if (dev
->hdr_type
& PCI_HEADER_TYPE_BRIDGE
) {
321 * If the error is reported by a bridge, we think this error
322 * is related to the downstream link of the bridge, so we
323 * do error recovery on all subordinates of the bridge instead
324 * of the bridge and clear the error status of the bridge.
326 if (cb
== report_error_detected
)
327 dev
->error_state
= state
;
328 pci_walk_bus(dev
->subordinate
, cb
, &result_data
);
329 if (cb
== report_resume
) {
330 pci_cleanup_aer_uncorrect_error_status(dev
);
331 dev
->error_state
= pci_channel_io_normal
;
336 * If the error is reported by an end point, we think this
337 * error is related to the upstream link of the end point.
339 pci_walk_bus(dev
->bus
, cb
, &result_data
);
342 return result_data
.result
;
345 struct find_aer_service_data
{
346 struct pcie_port_service_driver
*aer_driver
;
350 static int find_aer_service_iter(struct device
*device
, void *data
)
352 struct device_driver
*driver
;
353 struct pcie_port_service_driver
*service_driver
;
354 struct find_aer_service_data
*result
;
356 result
= (struct find_aer_service_data
*) data
;
358 if (device
->bus
== &pcie_port_bus_type
) {
359 struct pcie_port_data
*port_data
;
361 port_data
= pci_get_drvdata(to_pcie_device(device
)->port
);
362 if (port_data
->port_type
== PCIE_SW_DOWNSTREAM_PORT
)
363 result
->is_downstream
= 1;
365 driver
= device
->driver
;
367 service_driver
= to_service_driver(driver
);
368 if (service_driver
->service
== PCIE_PORT_SERVICE_AER
) {
369 result
->aer_driver
= service_driver
;
378 static void find_aer_service(struct pci_dev
*dev
,
379 struct find_aer_service_data
*data
)
382 retval
= device_for_each_child(&dev
->dev
, data
, find_aer_service_iter
);
385 static pci_ers_result_t
reset_link(struct pcie_device
*aerdev
,
388 struct pci_dev
*udev
;
389 pci_ers_result_t status
;
390 struct find_aer_service_data data
;
392 if (dev
->hdr_type
& PCI_HEADER_TYPE_BRIDGE
)
395 udev
= dev
->bus
->self
;
397 data
.is_downstream
= 0;
398 data
.aer_driver
= NULL
;
399 find_aer_service(udev
, &data
);
402 * Use the aer driver of the error agent firstly.
403 * If it hasn't the aer driver, use the root port's
405 if (!data
.aer_driver
|| !data
.aer_driver
->reset_link
) {
406 if (data
.is_downstream
&&
407 aerdev
->device
.driver
&&
408 to_service_driver(aerdev
->device
.driver
)->reset_link
) {
410 to_service_driver(aerdev
->device
.driver
);
412 dev_printk(KERN_DEBUG
, &dev
->dev
, "no link-reset "
414 return PCI_ERS_RESULT_DISCONNECT
;
418 status
= data
.aer_driver
->reset_link(udev
);
419 if (status
!= PCI_ERS_RESULT_RECOVERED
) {
420 dev_printk(KERN_DEBUG
, &dev
->dev
, "link reset at upstream "
421 "device %s failed\n", pci_name(udev
));
422 return PCI_ERS_RESULT_DISCONNECT
;
429 * do_recovery - handle nonfatal/fatal error recovery process
430 * @aerdev: pointer to a pcie_device data structure of root port
431 * @dev: pointer to a pci_dev data structure of agent detecting an error
432 * @severity: error severity type
434 * Invoked when an error is nonfatal/fatal. Once being invoked, broadcast
435 * error detected message to all downstream drivers within a hierarchy in
436 * question and return the returned code.
438 static pci_ers_result_t
do_recovery(struct pcie_device
*aerdev
,
442 pci_ers_result_t status
, result
= PCI_ERS_RESULT_RECOVERED
;
443 enum pci_channel_state state
;
445 if (severity
== AER_FATAL
)
446 state
= pci_channel_io_frozen
;
448 state
= pci_channel_io_normal
;
450 status
= broadcast_error_message(dev
,
453 report_error_detected
);
455 if (severity
== AER_FATAL
) {
456 result
= reset_link(aerdev
, dev
);
457 if (result
!= PCI_ERS_RESULT_RECOVERED
) {
458 /* TODO: Should panic here? */
463 if (status
== PCI_ERS_RESULT_CAN_RECOVER
)
464 status
= broadcast_error_message(dev
,
467 report_mmio_enabled
);
469 if (status
== PCI_ERS_RESULT_NEED_RESET
) {
471 * TODO: Should call platform-specific
472 * functions to reset slot before calling
473 * drivers' slot_reset callbacks?
475 status
= broadcast_error_message(dev
,
481 if (status
== PCI_ERS_RESULT_RECOVERED
)
482 broadcast_error_message(dev
,
491 * handle_error_source - handle logging error into an event log
492 * @aerdev: pointer to pcie_device data structure of the root port
493 * @dev: pointer to pci_dev data structure of error source device
494 * @info: comprehensive error information
496 * Invoked when an error being detected by Root Port.
498 static void handle_error_source(struct pcie_device
* aerdev
,
500 struct aer_err_info info
)
502 pci_ers_result_t status
= 0;
505 if (info
.severity
== AER_CORRECTABLE
) {
507 * Correctable error does not need software intevention.
508 * No need to go through error recovery process.
510 pos
= pci_find_ext_capability(dev
, PCI_EXT_CAP_ID_ERR
);
512 pci_write_config_dword(dev
, pos
+ PCI_ERR_COR_STATUS
,
515 status
= do_recovery(aerdev
, dev
, info
.severity
);
516 if (status
== PCI_ERS_RESULT_RECOVERED
) {
517 dev_printk(KERN_DEBUG
, &dev
->dev
, "AER driver "
518 "successfully recovered\n");
520 /* TODO: Should kernel panic here? */
521 dev_printk(KERN_DEBUG
, &dev
->dev
, "AER driver didn't "
528 * aer_enable_rootport - enable Root Port's interrupts when receiving messages
529 * @rpc: pointer to a Root Port data structure
531 * Invoked when PCIE bus loads AER service driver.
533 void aer_enable_rootport(struct aer_rpc
*rpc
)
535 struct pci_dev
*pdev
= rpc
->rpd
->port
;
540 pos
= pci_find_capability(pdev
, PCI_CAP_ID_EXP
);
541 /* Clear PCIE Capability's Device Status */
542 pci_read_config_word(pdev
, pos
+PCI_EXP_DEVSTA
, ®16
);
543 pci_write_config_word(pdev
, pos
+PCI_EXP_DEVSTA
, reg16
);
545 /* Disable system error generation in response to error messages */
546 pci_read_config_word(pdev
, pos
+ PCI_EXP_RTCTL
, ®16
);
547 reg16
&= ~(SYSTEM_ERROR_INTR_ON_MESG_MASK
);
548 pci_write_config_word(pdev
, pos
+ PCI_EXP_RTCTL
, reg16
);
550 aer_pos
= pci_find_ext_capability(pdev
, PCI_EXT_CAP_ID_ERR
);
551 /* Clear error status */
552 pci_read_config_dword(pdev
, aer_pos
+ PCI_ERR_ROOT_STATUS
, ®32
);
553 pci_write_config_dword(pdev
, aer_pos
+ PCI_ERR_ROOT_STATUS
, reg32
);
554 pci_read_config_dword(pdev
, aer_pos
+ PCI_ERR_COR_STATUS
, ®32
);
555 pci_write_config_dword(pdev
, aer_pos
+ PCI_ERR_COR_STATUS
, reg32
);
556 pci_read_config_dword(pdev
, aer_pos
+ PCI_ERR_UNCOR_STATUS
, ®32
);
557 pci_write_config_dword(pdev
, aer_pos
+ PCI_ERR_UNCOR_STATUS
, reg32
);
560 * Enable error reporting for the root port device and downstream port
563 set_downstream_devices_error_reporting(pdev
, true);
565 /* Enable Root Port's interrupt in response to error messages */
566 pci_write_config_dword(pdev
,
567 aer_pos
+ PCI_ERR_ROOT_COMMAND
,
568 ROOT_PORT_INTR_ON_MESG_MASK
);
572 * disable_root_aer - disable Root Port's interrupts when receiving messages
573 * @rpc: pointer to a Root Port data structure
575 * Invoked when PCIE bus unloads AER service driver.
577 static void disable_root_aer(struct aer_rpc
*rpc
)
579 struct pci_dev
*pdev
= rpc
->rpd
->port
;
584 * Disable error reporting for the root port device and downstream port
587 set_downstream_devices_error_reporting(pdev
, false);
589 pos
= pci_find_ext_capability(pdev
, PCI_EXT_CAP_ID_ERR
);
590 /* Disable Root's interrupt in response to error messages */
591 pci_write_config_dword(pdev
, pos
+ PCI_ERR_ROOT_COMMAND
, 0);
593 /* Clear Root's error status reg */
594 pci_read_config_dword(pdev
, pos
+ PCI_ERR_ROOT_STATUS
, ®32
);
595 pci_write_config_dword(pdev
, pos
+ PCI_ERR_ROOT_STATUS
, reg32
);
599 * get_e_source - retrieve an error source
600 * @rpc: pointer to the root port which holds an error
602 * Invoked by DPC handler to consume an error.
604 static struct aer_err_source
* get_e_source(struct aer_rpc
*rpc
)
606 struct aer_err_source
*e_source
;
609 /* Lock access to Root error producer/consumer index */
610 spin_lock_irqsave(&rpc
->e_lock
, flags
);
611 if (rpc
->prod_idx
== rpc
->cons_idx
) {
612 spin_unlock_irqrestore(&rpc
->e_lock
, flags
);
615 e_source
= &rpc
->e_sources
[rpc
->cons_idx
];
617 if (rpc
->cons_idx
== AER_ERROR_SOURCES_MAX
)
619 spin_unlock_irqrestore(&rpc
->e_lock
, flags
);
624 static int get_device_error_info(struct pci_dev
*dev
, struct aer_err_info
*info
)
628 pos
= pci_find_ext_capability(dev
, PCI_EXT_CAP_ID_ERR
);
630 /* The device might not support AER */
634 if (info
->severity
== AER_CORRECTABLE
) {
635 pci_read_config_dword(dev
, pos
+ PCI_ERR_COR_STATUS
,
637 if (!(info
->status
& ERR_CORRECTABLE_ERROR_MASK
))
638 return AER_UNSUCCESS
;
639 } else if (dev
->hdr_type
& PCI_HEADER_TYPE_BRIDGE
||
640 info
->severity
== AER_NONFATAL
) {
642 /* Link is still healthy for IO reads */
643 pci_read_config_dword(dev
, pos
+ PCI_ERR_UNCOR_STATUS
,
645 if (!(info
->status
& ERR_UNCORRECTABLE_ERROR_MASK
))
646 return AER_UNSUCCESS
;
648 if (info
->status
& AER_LOG_TLP_MASKS
) {
649 info
->flags
|= AER_TLP_HEADER_VALID_FLAG
;
650 pci_read_config_dword(dev
,
651 pos
+ PCI_ERR_HEADER_LOG
, &info
->tlp
.dw0
);
652 pci_read_config_dword(dev
,
653 pos
+ PCI_ERR_HEADER_LOG
+ 4, &info
->tlp
.dw1
);
654 pci_read_config_dword(dev
,
655 pos
+ PCI_ERR_HEADER_LOG
+ 8, &info
->tlp
.dw2
);
656 pci_read_config_dword(dev
,
657 pos
+ PCI_ERR_HEADER_LOG
+ 12, &info
->tlp
.dw3
);
665 * aer_isr_one_error - consume an error detected by root port
666 * @p_device: pointer to error root port service device
667 * @e_src: pointer to an error source
669 static void aer_isr_one_error(struct pcie_device
*p_device
,
670 struct aer_err_source
*e_src
)
672 struct device
*s_device
;
673 struct aer_err_info e_info
= {0, 0, 0,};
678 * There is a possibility that both correctable error and
679 * uncorrectable error being logged. Report correctable error first.
681 for (i
= 1; i
& ROOT_ERR_STATUS_MASKS
; i
<<= 2) {
684 if (!(e_src
->status
& i
))
687 /* Init comprehensive error information */
688 if (i
& PCI_ERR_ROOT_COR_RCV
) {
689 id
= ERR_COR_ID(e_src
->id
);
690 e_info
.severity
= AER_CORRECTABLE
;
692 id
= ERR_UNCOR_ID(e_src
->id
);
693 e_info
.severity
= ((e_src
->status
>> 6) & 1);
696 (PCI_ERR_ROOT_MULTI_COR_RCV
|
697 PCI_ERR_ROOT_MULTI_UNCOR_RCV
))
698 e_info
.flags
|= AER_MULTI_ERROR_VALID_FLAG
;
699 if (!(s_device
= find_source_device(p_device
->port
, id
))) {
700 printk(KERN_DEBUG
"%s->can't find device of ID%04x\n",
704 if (get_device_error_info(to_pci_dev(s_device
), &e_info
) ==
706 aer_print_error(to_pci_dev(s_device
), &e_info
);
707 handle_error_source(p_device
,
708 to_pci_dev(s_device
),
715 * aer_isr - consume errors detected by root port
716 * @work: definition of this work item
718 * Invoked, as DPC, when root port records new detected error
720 void aer_isr(struct work_struct
*work
)
722 struct aer_rpc
*rpc
= container_of(work
, struct aer_rpc
, dpc_handler
);
723 struct pcie_device
*p_device
= rpc
->rpd
;
724 struct aer_err_source
*e_src
;
726 mutex_lock(&rpc
->rpc_mutex
);
727 e_src
= get_e_source(rpc
);
729 aer_isr_one_error(p_device
, e_src
);
730 e_src
= get_e_source(rpc
);
732 mutex_unlock(&rpc
->rpc_mutex
);
734 wake_up(&rpc
->wait_release
);
738 * aer_delete_rootport - disable root port aer and delete service data
739 * @rpc: pointer to a root port device being deleted
741 * Invoked when AER service unloaded on a specific Root Port
743 void aer_delete_rootport(struct aer_rpc
*rpc
)
745 /* Disable root port AER itself */
746 disable_root_aer(rpc
);
752 * aer_init - provide AER initialization
753 * @dev: pointer to AER pcie device
755 * Invoked when AER service driver is loaded.
757 int aer_init(struct pcie_device
*dev
)
759 if (aer_osc_setup(dev
) && !forceload
)
765 EXPORT_SYMBOL_GPL(pci_enable_pcie_error_reporting
);
766 EXPORT_SYMBOL_GPL(pci_disable_pcie_error_reporting
);
767 EXPORT_SYMBOL_GPL(pci_cleanup_aer_uncorrect_error_status
);