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);
111 static int find_device_iter(struct device *device, void *data)
114 u16 id = *(unsigned long *)data;
115 u8 secondary, subordinate, d_bus = id >> 8;
117 if (device->bus == &pci_bus_type) {
118 dev = to_pci_dev(device);
119 if (id == ((dev->bus->number << 8) | dev->devfn)) {
123 *(unsigned long*)data = (unsigned long)device;
128 * If device is P2P, check if it is an upstream?
130 if (dev->hdr_type & PCI_HEADER_TYPE_BRIDGE) {
131 pci_read_config_byte(dev, PCI_SECONDARY_BUS,
133 pci_read_config_byte(dev, PCI_SUBORDINATE_BUS,
135 if (d_bus >= secondary && d_bus <= subordinate) {
136 *(unsigned long*)data = (unsigned long)device;
146 * find_source_device - search through device hierarchy for source device
147 * @parent: pointer to Root Port pci_dev data structure
148 * @id: device ID of agent who sends an error message to this Root Port
150 * Invoked when error is detected at the Root Port.
152 static struct device* find_source_device(struct pci_dev *parent, u16 id)
154 struct pci_dev *dev = parent;
155 struct device *device;
156 unsigned long device_addr;
159 /* Is Root Port an agent that sends error message? */
160 if (id == ((dev->bus->number << 8) | dev->devfn))
165 if ((status = device_for_each_child(&dev->dev,
166 &device_addr, find_device_iter))) {
167 device = (struct device*)device_addr;
168 dev = to_pci_dev(device);
169 if (id == ((dev->bus->number << 8) | dev->devfn))
177 static void report_error_detected(struct pci_dev *dev, void *data)
179 pci_ers_result_t vote;
180 struct pci_error_handlers *err_handler;
181 struct aer_broadcast_data *result_data;
182 result_data = (struct aer_broadcast_data *) data;
184 dev->error_state = result_data->state;
187 !dev->driver->err_handler ||
188 !dev->driver->err_handler->error_detected) {
189 if (result_data->state == pci_channel_io_frozen &&
190 !(dev->hdr_type & PCI_HEADER_TYPE_BRIDGE)) {
192 * In case of fatal recovery, if one of down-
193 * stream device has no driver. We might be
194 * unable to recover because a later insmod
195 * of a driver for this device is unaware of
198 dev_printk(KERN_DEBUG, &dev->dev, "device has %s\n",
200 "no AER-aware driver" : "no driver");
205 err_handler = dev->driver->err_handler;
206 vote = err_handler->error_detected(dev, result_data->state);
207 result_data->result = merge_result(result_data->result, vote);
211 static void report_mmio_enabled(struct pci_dev *dev, void *data)
213 pci_ers_result_t vote;
214 struct pci_error_handlers *err_handler;
215 struct aer_broadcast_data *result_data;
216 result_data = (struct aer_broadcast_data *) data;
219 !dev->driver->err_handler ||
220 !dev->driver->err_handler->mmio_enabled)
223 err_handler = dev->driver->err_handler;
224 vote = err_handler->mmio_enabled(dev);
225 result_data->result = merge_result(result_data->result, vote);
229 static void report_slot_reset(struct pci_dev *dev, void *data)
231 pci_ers_result_t vote;
232 struct pci_error_handlers *err_handler;
233 struct aer_broadcast_data *result_data;
234 result_data = (struct aer_broadcast_data *) data;
237 !dev->driver->err_handler ||
238 !dev->driver->err_handler->slot_reset)
241 err_handler = dev->driver->err_handler;
242 vote = err_handler->slot_reset(dev);
243 result_data->result = merge_result(result_data->result, vote);
247 static void report_resume(struct pci_dev *dev, void *data)
249 struct pci_error_handlers *err_handler;
251 dev->error_state = pci_channel_io_normal;
254 !dev->driver->err_handler ||
255 !dev->driver->err_handler->slot_reset)
258 err_handler = dev->driver->err_handler;
259 err_handler->resume(dev);
264 * broadcast_error_message - handle message broadcast to downstream drivers
265 * @dev: pointer to from where in a hierarchy message is broadcasted down
266 * @state: error state
267 * @error_mesg: message to print
268 * @cb: callback to be broadcasted
270 * Invoked during error recovery process. Once being invoked, the content
271 * of error severity will be broadcasted to all downstream drivers in a
272 * hierarchy in question.
274 static pci_ers_result_t broadcast_error_message(struct pci_dev *dev,
275 enum pci_channel_state state,
277 void (*cb)(struct pci_dev *, void *))
279 struct aer_broadcast_data result_data;
281 dev_printk(KERN_DEBUG, &dev->dev, "broadcast %s message\n", error_mesg);
282 result_data.state = state;
283 if (cb == report_error_detected)
284 result_data.result = PCI_ERS_RESULT_CAN_RECOVER;
286 result_data.result = PCI_ERS_RESULT_RECOVERED;
288 if (dev->hdr_type & PCI_HEADER_TYPE_BRIDGE) {
290 * If the error is reported by a bridge, we think this error
291 * is related to the downstream link of the bridge, so we
292 * do error recovery on all subordinates of the bridge instead
293 * of the bridge and clear the error status of the bridge.
295 if (cb == report_error_detected)
296 dev->error_state = state;
297 pci_walk_bus(dev->subordinate, cb, &result_data);
298 if (cb == report_resume) {
299 pci_cleanup_aer_uncorrect_error_status(dev);
300 dev->error_state = pci_channel_io_normal;
305 * If the error is reported by an end point, we think this
306 * error is related to the upstream link of the end point.
308 pci_walk_bus(dev->bus, cb, &result_data);
311 return result_data.result;
314 struct find_aer_service_data {
315 struct pcie_port_service_driver *aer_driver;
319 static int find_aer_service_iter(struct device *device, void *data)
321 struct device_driver *driver;
322 struct pcie_port_service_driver *service_driver;
323 struct pcie_device *pcie_dev;
324 struct find_aer_service_data *result;
326 result = (struct find_aer_service_data *) data;
328 if (device->bus == &pcie_port_bus_type) {
329 pcie_dev = to_pcie_device(device);
330 if (pcie_dev->id.port_type == PCIE_SW_DOWNSTREAM_PORT)
331 result->is_downstream = 1;
333 driver = device->driver;
335 service_driver = to_service_driver(driver);
336 if (service_driver->id_table->service_type ==
337 PCIE_PORT_SERVICE_AER) {
338 result->aer_driver = service_driver;
347 static void find_aer_service(struct pci_dev *dev,
348 struct find_aer_service_data *data)
351 retval = device_for_each_child(&dev->dev, data, find_aer_service_iter);
354 static pci_ers_result_t reset_link(struct pcie_device *aerdev,
357 struct pci_dev *udev;
358 pci_ers_result_t status;
359 struct find_aer_service_data data;
361 if (dev->hdr_type & PCI_HEADER_TYPE_BRIDGE)
364 udev= dev->bus->self;
366 data.is_downstream = 0;
367 data.aer_driver = NULL;
368 find_aer_service(udev, &data);
371 * Use the aer driver of the error agent firstly.
372 * If it hasn't the aer driver, use the root port's
374 if (!data.aer_driver || !data.aer_driver->reset_link) {
375 if (data.is_downstream &&
376 aerdev->device.driver &&
377 to_service_driver(aerdev->device.driver)->reset_link) {
379 to_service_driver(aerdev->device.driver);
381 dev_printk(KERN_DEBUG, &dev->dev, "no link-reset "
383 return PCI_ERS_RESULT_DISCONNECT;
387 status = data.aer_driver->reset_link(udev);
388 if (status != PCI_ERS_RESULT_RECOVERED) {
389 dev_printk(KERN_DEBUG, &dev->dev, "link reset at upstream "
390 "device %s failed\n", pci_name(udev));
391 return PCI_ERS_RESULT_DISCONNECT;
398 * do_recovery - handle nonfatal/fatal error recovery process
399 * @aerdev: pointer to a pcie_device data structure of root port
400 * @dev: pointer to a pci_dev data structure of agent detecting an error
401 * @severity: error severity type
403 * Invoked when an error is nonfatal/fatal. Once being invoked, broadcast
404 * error detected message to all downstream drivers within a hierarchy in
405 * question and return the returned code.
407 static pci_ers_result_t do_recovery(struct pcie_device *aerdev,
411 pci_ers_result_t status, result = PCI_ERS_RESULT_RECOVERED;
412 enum pci_channel_state state;
414 if (severity == AER_FATAL)
415 state = pci_channel_io_frozen;
417 state = pci_channel_io_normal;
419 status = broadcast_error_message(dev,
422 report_error_detected);
424 if (severity == AER_FATAL) {
425 result = reset_link(aerdev, dev);
426 if (result != PCI_ERS_RESULT_RECOVERED) {
427 /* TODO: Should panic here? */
432 if (status == PCI_ERS_RESULT_CAN_RECOVER)
433 status = broadcast_error_message(dev,
436 report_mmio_enabled);
438 if (status == PCI_ERS_RESULT_NEED_RESET) {
440 * TODO: Should call platform-specific
441 * functions to reset slot before calling
442 * drivers' slot_reset callbacks?
444 status = broadcast_error_message(dev,
450 if (status == PCI_ERS_RESULT_RECOVERED)
451 broadcast_error_message(dev,
460 * handle_error_source - handle logging error into an event log
461 * @aerdev: pointer to pcie_device data structure of the root port
462 * @dev: pointer to pci_dev data structure of error source device
463 * @info: comprehensive error information
465 * Invoked when an error being detected by Root Port.
467 static void handle_error_source(struct pcie_device * aerdev,
469 struct aer_err_info info)
471 pci_ers_result_t status = 0;
474 if (info.severity == AER_CORRECTABLE) {
476 * Correctable error does not need software intevention.
477 * No need to go through error recovery process.
479 pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ERR);
481 pci_write_config_dword(dev, pos + PCI_ERR_COR_STATUS,
484 status = do_recovery(aerdev, dev, info.severity);
485 if (status == PCI_ERS_RESULT_RECOVERED) {
486 dev_printk(KERN_DEBUG, &dev->dev, "AER driver "
487 "successfully recovered\n");
489 /* TODO: Should kernel panic here? */
490 dev_printk(KERN_DEBUG, &dev->dev, "AER driver didn't "
497 * aer_enable_rootport - enable Root Port's interrupts when receiving messages
498 * @rpc: pointer to a Root Port data structure
500 * Invoked when PCIE bus loads AER service driver.
502 void aer_enable_rootport(struct aer_rpc *rpc)
504 struct pci_dev *pdev = rpc->rpd->port;
509 pos = pci_find_capability(pdev, PCI_CAP_ID_EXP);
510 /* Clear PCIE Capability's Device Status */
511 pci_read_config_word(pdev, pos+PCI_EXP_DEVSTA, ®16);
512 pci_write_config_word(pdev, pos+PCI_EXP_DEVSTA, reg16);
514 /* Disable system error generation in response to error messages */
515 pci_read_config_word(pdev, pos + PCI_EXP_RTCTL, ®16);
516 reg16 &= ~(SYSTEM_ERROR_INTR_ON_MESG_MASK);
517 pci_write_config_word(pdev, pos + PCI_EXP_RTCTL, reg16);
519 aer_pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_ERR);
520 /* Clear error status */
521 pci_read_config_dword(pdev, aer_pos + PCI_ERR_ROOT_STATUS, ®32);
522 pci_write_config_dword(pdev, aer_pos + PCI_ERR_ROOT_STATUS, reg32);
523 pci_read_config_dword(pdev, aer_pos + PCI_ERR_COR_STATUS, ®32);
524 pci_write_config_dword(pdev, aer_pos + PCI_ERR_COR_STATUS, reg32);
525 pci_read_config_dword(pdev, aer_pos + PCI_ERR_UNCOR_STATUS, ®32);
526 pci_write_config_dword(pdev, aer_pos + PCI_ERR_UNCOR_STATUS, reg32);
528 /* Enable Root Port device reporting error itself */
529 pci_read_config_word(pdev, pos+PCI_EXP_DEVCTL, ®16);
531 PCI_EXP_DEVCTL_CERE |
532 PCI_EXP_DEVCTL_NFERE |
533 PCI_EXP_DEVCTL_FERE |
535 pci_write_config_word(pdev, pos+PCI_EXP_DEVCTL,
538 /* Enable Root Port's interrupt in response to error messages */
539 pci_write_config_dword(pdev,
540 aer_pos + PCI_ERR_ROOT_COMMAND,
541 ROOT_PORT_INTR_ON_MESG_MASK);
545 * disable_root_aer - disable Root Port's interrupts when receiving messages
546 * @rpc: pointer to a Root Port data structure
548 * Invoked when PCIE bus unloads AER service driver.
550 static void disable_root_aer(struct aer_rpc *rpc)
552 struct pci_dev *pdev = rpc->rpd->port;
556 pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_ERR);
557 /* Disable Root's interrupt in response to error messages */
558 pci_write_config_dword(pdev, pos + PCI_ERR_ROOT_COMMAND, 0);
560 /* Clear Root's error status reg */
561 pci_read_config_dword(pdev, pos + PCI_ERR_ROOT_STATUS, ®32);
562 pci_write_config_dword(pdev, pos + PCI_ERR_ROOT_STATUS, reg32);
566 * get_e_source - retrieve an error source
567 * @rpc: pointer to the root port which holds an error
569 * Invoked by DPC handler to consume an error.
571 static struct aer_err_source* get_e_source(struct aer_rpc *rpc)
573 struct aer_err_source *e_source;
576 /* Lock access to Root error producer/consumer index */
577 spin_lock_irqsave(&rpc->e_lock, flags);
578 if (rpc->prod_idx == rpc->cons_idx) {
579 spin_unlock_irqrestore(&rpc->e_lock, flags);
582 e_source = &rpc->e_sources[rpc->cons_idx];
584 if (rpc->cons_idx == AER_ERROR_SOURCES_MAX)
586 spin_unlock_irqrestore(&rpc->e_lock, flags);
591 static int get_device_error_info(struct pci_dev *dev, struct aer_err_info *info)
595 pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ERR);
597 /* The device might not support AER */
601 if (info->severity == AER_CORRECTABLE) {
602 pci_read_config_dword(dev, pos + PCI_ERR_COR_STATUS,
604 if (!(info->status & ERR_CORRECTABLE_ERROR_MASK))
605 return AER_UNSUCCESS;
606 } else if (dev->hdr_type & PCI_HEADER_TYPE_BRIDGE ||
607 info->severity == AER_NONFATAL) {
609 /* Link is still healthy for IO reads */
610 pci_read_config_dword(dev, pos + PCI_ERR_UNCOR_STATUS,
612 if (!(info->status & ERR_UNCORRECTABLE_ERROR_MASK))
613 return AER_UNSUCCESS;
615 if (info->status & AER_LOG_TLP_MASKS) {
616 info->flags |= AER_TLP_HEADER_VALID_FLAG;
617 pci_read_config_dword(dev,
618 pos + PCI_ERR_HEADER_LOG, &info->tlp.dw0);
619 pci_read_config_dword(dev,
620 pos + PCI_ERR_HEADER_LOG + 4, &info->tlp.dw1);
621 pci_read_config_dword(dev,
622 pos + PCI_ERR_HEADER_LOG + 8, &info->tlp.dw2);
623 pci_read_config_dword(dev,
624 pos + PCI_ERR_HEADER_LOG + 12, &info->tlp.dw3);
632 * aer_isr_one_error - consume an error detected by root port
633 * @p_device: pointer to error root port service device
634 * @e_src: pointer to an error source
636 static void aer_isr_one_error(struct pcie_device *p_device,
637 struct aer_err_source *e_src)
639 struct device *s_device;
640 struct aer_err_info e_info = {0, 0, 0,};
645 * There is a possibility that both correctable error and
646 * uncorrectable error being logged. Report correctable error first.
648 for (i = 1; i & ROOT_ERR_STATUS_MASKS ; i <<= 2) {
651 if (!(e_src->status & i))
654 /* Init comprehensive error information */
655 if (i & PCI_ERR_ROOT_COR_RCV) {
656 id = ERR_COR_ID(e_src->id);
657 e_info.severity = AER_CORRECTABLE;
659 id = ERR_UNCOR_ID(e_src->id);
660 e_info.severity = ((e_src->status >> 6) & 1);
663 (PCI_ERR_ROOT_MULTI_COR_RCV |
664 PCI_ERR_ROOT_MULTI_UNCOR_RCV))
665 e_info.flags |= AER_MULTI_ERROR_VALID_FLAG;
666 if (!(s_device = find_source_device(p_device->port, id))) {
667 printk(KERN_DEBUG "%s->can't find device of ID%04x\n",
671 if (get_device_error_info(to_pci_dev(s_device), &e_info) ==
673 aer_print_error(to_pci_dev(s_device), &e_info);
674 handle_error_source(p_device,
675 to_pci_dev(s_device),
682 * aer_isr - consume errors detected by root port
683 * @work: definition of this work item
685 * Invoked, as DPC, when root port records new detected error
687 void aer_isr(struct work_struct *work)
689 struct aer_rpc *rpc = container_of(work, struct aer_rpc, dpc_handler);
690 struct pcie_device *p_device = rpc->rpd;
691 struct aer_err_source *e_src;
693 mutex_lock(&rpc->rpc_mutex);
694 e_src = get_e_source(rpc);
696 aer_isr_one_error(p_device, e_src);
697 e_src = get_e_source(rpc);
699 mutex_unlock(&rpc->rpc_mutex);
701 wake_up(&rpc->wait_release);
705 * aer_delete_rootport - disable root port aer and delete service data
706 * @rpc: pointer to a root port device being deleted
708 * Invoked when AER service unloaded on a specific Root Port
710 void aer_delete_rootport(struct aer_rpc *rpc)
712 /* Disable root port AER itself */
713 disable_root_aer(rpc);
719 * aer_init - provide AER initialization
720 * @dev: pointer to AER pcie device
722 * Invoked when AER service driver is loaded.
724 int aer_init(struct pcie_device *dev)
726 if (aer_osc_setup(dev) && !forceload)
732 EXPORT_SYMBOL_GPL(pci_enable_pcie_error_reporting);
733 EXPORT_SYMBOL_GPL(pci_disable_pcie_error_reporting);
734 EXPORT_SYMBOL_GPL(pci_cleanup_aer_uncorrect_error_status);