2 * PCI Error Recovery Driver for RPA-compliant PPC64 platform.
3 * Copyright IBM Corp. 2004 2005
4 * Copyright Linas Vepstas <linas@linas.org> 2004, 2005
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or (at
11 * your option) any later version.
13 * This program is distributed in the hope that it will be useful, but
14 * WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
16 * NON INFRINGEMENT. See the GNU General Public License for more
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
23 * Send comments and feedback to Linas Vepstas <linas@austin.ibm.com>
25 #include <linux/delay.h>
26 #include <linux/interrupt.h>
27 #include <linux/irq.h>
28 #include <linux/module.h>
29 #include <linux/pci.h>
31 #include <asm/eeh_event.h>
32 #include <asm/ppc-pci.h>
33 #include <asm/pci-bridge.h>
38 struct list_head removed_vf_list;
39 int removed_dev_count;
42 static int eeh_result_priority(enum pci_ers_result result)
45 case PCI_ERS_RESULT_NONE:
47 case PCI_ERS_RESULT_NO_AER_DRIVER:
49 case PCI_ERS_RESULT_RECOVERED:
51 case PCI_ERS_RESULT_CAN_RECOVER:
53 case PCI_ERS_RESULT_DISCONNECT:
55 case PCI_ERS_RESULT_NEED_RESET:
58 WARN_ONCE(1, "Unknown pci_ers_result value: %d\n", (int)result);
63 static const char *pci_ers_result_name(enum pci_ers_result result)
66 case PCI_ERS_RESULT_NONE:
68 case PCI_ERS_RESULT_CAN_RECOVER:
70 case PCI_ERS_RESULT_NEED_RESET:
72 case PCI_ERS_RESULT_DISCONNECT:
74 case PCI_ERS_RESULT_RECOVERED:
76 case PCI_ERS_RESULT_NO_AER_DRIVER:
77 return "no AER driver";
79 WARN_ONCE(1, "Unknown result type: %d\n", (int)result);
84 static __printf(2, 3) void eeh_edev_info(const struct eeh_dev *edev,
95 printk(KERN_INFO "EEH: PE#%x (PCI %s): %pV\n", edev->pe_config_addr,
96 edev->pdev ? dev_name(&edev->pdev->dev) : "none", &vaf);
101 static enum pci_ers_result pci_ers_merge_result(enum pci_ers_result old,
102 enum pci_ers_result new)
104 if (eeh_result_priority(new) > eeh_result_priority(old))
109 static bool eeh_dev_removed(struct eeh_dev *edev)
111 return !edev || (edev->mode & EEH_DEV_REMOVED);
114 static bool eeh_edev_actionable(struct eeh_dev *edev)
116 return (edev->pdev && !eeh_dev_removed(edev) &&
117 !eeh_pe_passed(edev->pe));
121 * eeh_pcid_get - Get the PCI device driver
124 * The function is used to retrieve the PCI device driver for
125 * the indicated PCI device. Besides, we will increase the reference
126 * of the PCI device driver to prevent that being unloaded on
127 * the fly. Otherwise, kernel crash would be seen.
129 static inline struct pci_driver *eeh_pcid_get(struct pci_dev *pdev)
131 if (!pdev || !pdev->driver)
134 if (!try_module_get(pdev->driver->driver.owner))
141 * eeh_pcid_put - Dereference on the PCI device driver
144 * The function is called to do dereference on the PCI device
145 * driver of the indicated PCI device.
147 static inline void eeh_pcid_put(struct pci_dev *pdev)
149 if (!pdev || !pdev->driver)
152 module_put(pdev->driver->driver.owner);
156 * eeh_disable_irq - Disable interrupt for the recovering device
159 * This routine must be called when reporting temporary or permanent
160 * error to the particular PCI device to disable interrupt of that
161 * device. If the device has enabled MSI or MSI-X interrupt, we needn't
162 * do real work because EEH should freeze DMA transfers for those PCI
163 * devices encountering EEH errors, which includes MSI or MSI-X.
165 static void eeh_disable_irq(struct eeh_dev *edev)
167 /* Don't disable MSI and MSI-X interrupts. They are
168 * effectively disabled by the DMA Stopped state
169 * when an EEH error occurs.
171 if (edev->pdev->msi_enabled || edev->pdev->msix_enabled)
174 if (!irq_has_action(edev->pdev->irq))
177 edev->mode |= EEH_DEV_IRQ_DISABLED;
178 disable_irq_nosync(edev->pdev->irq);
182 * eeh_enable_irq - Enable interrupt for the recovering device
185 * This routine must be called to enable interrupt while failed
186 * device could be resumed.
188 static void eeh_enable_irq(struct eeh_dev *edev)
190 if ((edev->mode) & EEH_DEV_IRQ_DISABLED) {
191 edev->mode &= ~EEH_DEV_IRQ_DISABLED;
195 * This is just ass backwards. This maze has
196 * unbalanced irq_enable/disable calls. So instead of
197 * finding the root cause it works around the warning
198 * in the irq_enable code by conditionally calling
201 * That's just wrong.The warning in the core code is
202 * there to tell people to fix their asymmetries in
203 * their own code, not by abusing the core information
206 * I so wish that the assymetry would be the other way
207 * round and a few more irq_disable calls render that
208 * shit unusable forever.
212 if (irqd_irq_disabled(irq_get_irq_data(edev->pdev->irq)))
213 enable_irq(edev->pdev->irq);
217 static void *eeh_dev_save_state(struct eeh_dev *edev, void *userdata)
219 struct pci_dev *pdev;
225 * We cannot access the config space on some adapters.
226 * Otherwise, it will cause fenced PHB. We don't save
227 * the content in their config space and will restore
228 * from the initial config space saved when the EEH
231 if (edev->pe && (edev->pe->state & EEH_PE_CFG_RESTRICTED))
234 pdev = eeh_dev_to_pci_dev(edev);
238 pci_save_state(pdev);
242 static void eeh_set_channel_state(struct eeh_pe *root, enum pci_channel_state s)
245 struct eeh_dev *edev, *tmp;
247 eeh_for_each_pe(root, pe)
248 eeh_pe_for_each_dev(pe, edev, tmp)
249 if (eeh_edev_actionable(edev))
250 edev->pdev->error_state = s;
253 static void eeh_set_irq_state(struct eeh_pe *root, bool enable)
256 struct eeh_dev *edev, *tmp;
258 eeh_for_each_pe(root, pe) {
259 eeh_pe_for_each_dev(pe, edev, tmp) {
260 if (!eeh_edev_actionable(edev))
263 if (!eeh_pcid_get(edev->pdev))
267 eeh_enable_irq(edev);
269 eeh_disable_irq(edev);
271 eeh_pcid_put(edev->pdev);
276 typedef enum pci_ers_result (*eeh_report_fn)(struct eeh_dev *,
277 struct pci_driver *);
278 static void eeh_pe_report_edev(struct eeh_dev *edev, eeh_report_fn fn,
279 enum pci_ers_result *result)
281 struct pci_driver *driver;
282 enum pci_ers_result new_result;
285 eeh_edev_info(edev, "no device");
288 device_lock(&edev->pdev->dev);
289 if (eeh_edev_actionable(edev)) {
290 driver = eeh_pcid_get(edev->pdev);
293 eeh_edev_info(edev, "no driver");
294 else if (!driver->err_handler)
295 eeh_edev_info(edev, "driver not EEH aware");
296 else if (edev->mode & EEH_DEV_NO_HANDLER)
297 eeh_edev_info(edev, "driver bound too late");
299 new_result = fn(edev, driver);
300 eeh_edev_info(edev, "%s driver reports: '%s'",
302 pci_ers_result_name(new_result));
304 *result = pci_ers_merge_result(*result,
308 eeh_pcid_put(edev->pdev);
310 eeh_edev_info(edev, "not actionable (%d,%d,%d)", !!edev->pdev,
311 !eeh_dev_removed(edev), !eeh_pe_passed(edev->pe));
313 device_unlock(&edev->pdev->dev);
316 static void eeh_pe_report(const char *name, struct eeh_pe *root,
317 eeh_report_fn fn, enum pci_ers_result *result)
320 struct eeh_dev *edev, *tmp;
322 pr_info("EEH: Beginning: '%s'\n", name);
323 eeh_for_each_pe(root, pe) eeh_pe_for_each_dev(pe, edev, tmp)
324 eeh_pe_report_edev(edev, fn, result);
326 pr_info("EEH: Finished:'%s' with aggregate recovery state:'%s'\n",
327 name, pci_ers_result_name(*result));
329 pr_info("EEH: Finished:'%s'", name);
333 * eeh_report_error - Report pci error to each device driver
335 * @driver: device's PCI driver
337 * Report an EEH error to each device driver.
339 static enum pci_ers_result eeh_report_error(struct eeh_dev *edev,
340 struct pci_driver *driver)
342 enum pci_ers_result rc;
343 struct pci_dev *dev = edev->pdev;
345 if (!driver->err_handler->error_detected)
346 return PCI_ERS_RESULT_NONE;
348 eeh_edev_info(edev, "Invoking %s->error_detected(IO frozen)",
350 rc = driver->err_handler->error_detected(dev, pci_channel_io_frozen);
352 edev->in_error = true;
353 pci_uevent_ers(dev, PCI_ERS_RESULT_NONE);
358 * eeh_report_mmio_enabled - Tell drivers that MMIO has been enabled
360 * @driver: device's PCI driver
362 * Tells each device driver that IO ports, MMIO and config space I/O
365 static enum pci_ers_result eeh_report_mmio_enabled(struct eeh_dev *edev,
366 struct pci_driver *driver)
368 if (!driver->err_handler->mmio_enabled)
369 return PCI_ERS_RESULT_NONE;
370 eeh_edev_info(edev, "Invoking %s->mmio_enabled()", driver->name);
371 return driver->err_handler->mmio_enabled(edev->pdev);
375 * eeh_report_reset - Tell device that slot has been reset
377 * @driver: device's PCI driver
379 * This routine must be called while EEH tries to reset particular
380 * PCI device so that the associated PCI device driver could take
381 * some actions, usually to save data the driver needs so that the
382 * driver can work again while the device is recovered.
384 static enum pci_ers_result eeh_report_reset(struct eeh_dev *edev,
385 struct pci_driver *driver)
387 if (!driver->err_handler->slot_reset || !edev->in_error)
388 return PCI_ERS_RESULT_NONE;
389 eeh_edev_info(edev, "Invoking %s->slot_reset()", driver->name);
390 return driver->err_handler->slot_reset(edev->pdev);
393 static void *eeh_dev_restore_state(struct eeh_dev *edev, void *userdata)
395 struct pci_dev *pdev;
401 * The content in the config space isn't saved because
402 * the blocked config space on some adapters. We have
403 * to restore the initial saved config space when the
404 * EEH device is created.
406 if (edev->pe && (edev->pe->state & EEH_PE_CFG_RESTRICTED)) {
407 if (list_is_last(&edev->entry, &edev->pe->edevs))
408 eeh_pe_restore_bars(edev->pe);
413 pdev = eeh_dev_to_pci_dev(edev);
417 pci_restore_state(pdev);
422 * eeh_report_resume - Tell device to resume normal operations
424 * @driver: device's PCI driver
426 * This routine must be called to notify the device driver that it
427 * could resume so that the device driver can do some initialization
428 * to make the recovered device work again.
430 static enum pci_ers_result eeh_report_resume(struct eeh_dev *edev,
431 struct pci_driver *driver)
433 if (!driver->err_handler->resume || !edev->in_error)
434 return PCI_ERS_RESULT_NONE;
436 eeh_edev_info(edev, "Invoking %s->resume()", driver->name);
437 driver->err_handler->resume(edev->pdev);
439 pci_uevent_ers(edev->pdev, PCI_ERS_RESULT_RECOVERED);
440 #ifdef CONFIG_PCI_IOV
441 if (eeh_ops->notify_resume && eeh_dev_to_pdn(edev))
442 eeh_ops->notify_resume(eeh_dev_to_pdn(edev));
444 return PCI_ERS_RESULT_NONE;
448 * eeh_report_failure - Tell device driver that device is dead.
450 * @driver: device's PCI driver
452 * This informs the device driver that the device is permanently
453 * dead, and that no further recovery attempts will be made on it.
455 static enum pci_ers_result eeh_report_failure(struct eeh_dev *edev,
456 struct pci_driver *driver)
458 enum pci_ers_result rc;
460 if (!driver->err_handler->error_detected)
461 return PCI_ERS_RESULT_NONE;
463 eeh_edev_info(edev, "Invoking %s->error_detected(permanent failure)",
465 rc = driver->err_handler->error_detected(edev->pdev,
466 pci_channel_io_perm_failure);
468 pci_uevent_ers(edev->pdev, PCI_ERS_RESULT_DISCONNECT);
472 static void *eeh_add_virt_device(struct eeh_dev *edev)
474 struct pci_driver *driver;
475 struct pci_dev *dev = eeh_dev_to_pci_dev(edev);
476 struct pci_dn *pdn = eeh_dev_to_pdn(edev);
478 if (!(edev->physfn)) {
479 pr_warn("%s: EEH dev %04x:%02x:%02x.%01x not for VF\n",
480 __func__, pdn->phb->global_number, pdn->busno,
481 PCI_SLOT(pdn->devfn), PCI_FUNC(pdn->devfn));
485 driver = eeh_pcid_get(dev);
487 if (driver->err_handler) {
494 #ifdef CONFIG_PCI_IOV
495 pci_iov_add_virtfn(edev->physfn, pdn->vf_index);
500 static void *eeh_rmv_device(struct eeh_dev *edev, void *userdata)
502 struct pci_driver *driver;
503 struct pci_dev *dev = eeh_dev_to_pci_dev(edev);
504 struct eeh_rmv_data *rmv_data = (struct eeh_rmv_data *)userdata;
507 * Actually, we should remove the PCI bridges as well.
508 * However, that's lots of complexity to do that,
509 * particularly some of devices under the bridge might
510 * support EEH. So we just care about PCI devices for
513 if (!eeh_edev_actionable(edev) ||
514 (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE))
518 driver = eeh_pcid_get(dev);
520 if (driver->err_handler &&
521 driver->err_handler->error_detected &&
522 driver->err_handler->slot_reset) {
530 /* Remove it from PCI subsystem */
531 pr_info("EEH: Removing %s without EEH sensitive driver\n",
533 edev->mode |= EEH_DEV_DISCONNECTED;
535 rmv_data->removed_dev_count++;
538 #ifdef CONFIG_PCI_IOV
539 struct pci_dn *pdn = eeh_dev_to_pdn(edev);
541 pci_iov_remove_virtfn(edev->physfn, pdn->vf_index);
545 * We have to set the VF PE number to invalid one, which is
546 * required to plug the VF successfully.
548 pdn->pe_number = IODA_INVALID_PE;
551 list_add(&edev->rmv_entry, &rmv_data->removed_vf_list);
553 pci_lock_rescan_remove();
554 pci_stop_and_remove_bus_device(dev);
555 pci_unlock_rescan_remove();
561 static void *eeh_pe_detach_dev(struct eeh_pe *pe, void *userdata)
563 struct eeh_dev *edev, *tmp;
565 eeh_pe_for_each_dev(pe, edev, tmp) {
566 if (!(edev->mode & EEH_DEV_DISCONNECTED))
569 edev->mode &= ~(EEH_DEV_DISCONNECTED | EEH_DEV_IRQ_DISABLED);
570 eeh_rmv_from_parent_pe(edev);
577 * Explicitly clear PE's frozen state for PowerNV where
578 * we have frozen PE until BAR restore is completed. It's
579 * harmless to clear it for pSeries. To be consistent with
580 * PE reset (for 3 times), we try to clear the frozen state
581 * for 3 times as well.
583 static int eeh_clear_pe_frozen_state(struct eeh_pe *root, bool include_passed)
588 eeh_for_each_pe(root, pe) {
589 if (include_passed || !eeh_pe_passed(pe)) {
590 for (i = 0; i < 3; i++)
591 if (!eeh_unfreeze_pe(pe))
597 eeh_pe_state_clear(root, EEH_PE_ISOLATED, include_passed);
601 int eeh_pe_reset_and_recover(struct eeh_pe *pe)
605 /* Bail if the PE is being recovered */
606 if (pe->state & EEH_PE_RECOVERING)
609 /* Put the PE into recovery mode */
610 eeh_pe_state_mark(pe, EEH_PE_RECOVERING);
613 eeh_pe_dev_traverse(pe, eeh_dev_save_state, NULL);
616 ret = eeh_pe_reset_full(pe, true);
618 eeh_pe_state_clear(pe, EEH_PE_RECOVERING, true);
622 /* Unfreeze the PE */
623 ret = eeh_clear_pe_frozen_state(pe, true);
625 eeh_pe_state_clear(pe, EEH_PE_RECOVERING, true);
629 /* Restore device state */
630 eeh_pe_dev_traverse(pe, eeh_dev_restore_state, NULL);
632 /* Clear recovery mode */
633 eeh_pe_state_clear(pe, EEH_PE_RECOVERING, true);
639 * eeh_reset_device - Perform actual reset of a pci slot
640 * @driver_eeh_aware: Does the device's driver provide EEH support?
642 * @bus: PCI bus corresponding to the isolcated slot
643 * @rmv_data: Optional, list to record removed devices
645 * This routine must be called to do reset on the indicated PE.
646 * During the reset, udev might be invoked because those affected
647 * PCI devices will be removed and then added.
649 static int eeh_reset_device(struct eeh_pe *pe, struct pci_bus *bus,
650 struct eeh_rmv_data *rmv_data,
651 bool driver_eeh_aware)
655 struct eeh_dev *edev;
656 struct eeh_pe *tmp_pe;
657 bool any_passed = false;
659 eeh_for_each_pe(pe, tmp_pe)
660 any_passed |= eeh_pe_passed(tmp_pe);
662 /* pcibios will clear the counter; save the value */
663 cnt = pe->freeze_count;
667 * We don't remove the corresponding PE instances because
668 * we need the information afterwords. The attached EEH
669 * devices are expected to be attached soon when calling
670 * into pci_hp_add_devices().
672 eeh_pe_state_mark(pe, EEH_PE_KEEP);
673 if (any_passed || driver_eeh_aware || (pe->type & EEH_PE_VF)) {
674 eeh_pe_dev_traverse(pe, eeh_rmv_device, rmv_data);
676 pci_lock_rescan_remove();
677 pci_hp_remove_devices(bus);
678 pci_unlock_rescan_remove();
682 * Reset the pci controller. (Asserts RST#; resets config space).
683 * Reconfigure bridges and devices. Don't try to bring the system
684 * up if the reset failed for some reason.
686 * During the reset, it's very dangerous to have uncontrolled PCI
687 * config accesses. So we prefer to block them. However, controlled
688 * PCI config accesses initiated from EEH itself are allowed.
690 rc = eeh_pe_reset_full(pe, false);
694 pci_lock_rescan_remove();
697 eeh_ops->configure_bridge(pe);
698 eeh_pe_restore_bars(pe);
700 /* Clear frozen state */
701 rc = eeh_clear_pe_frozen_state(pe, false);
703 pci_unlock_rescan_remove();
707 /* Give the system 5 seconds to finish running the user-space
708 * hotplug shutdown scripts, e.g. ifdown for ethernet. Yes,
709 * this is a hack, but if we don't do this, and try to bring
710 * the device up before the scripts have taken it down,
711 * potentially weird things happen.
713 if (!driver_eeh_aware || rmv_data->removed_dev_count) {
714 pr_info("EEH: Sleep 5s ahead of %s hotplug\n",
715 (driver_eeh_aware ? "partial" : "complete"));
719 * The EEH device is still connected with its parent
720 * PE. We should disconnect it so the binding can be
721 * rebuilt when adding PCI devices.
723 edev = list_first_entry(&pe->edevs, struct eeh_dev, entry);
724 eeh_pe_traverse(pe, eeh_pe_detach_dev, NULL);
725 if (pe->type & EEH_PE_VF) {
726 eeh_add_virt_device(edev);
728 if (!driver_eeh_aware)
729 eeh_pe_state_clear(pe, EEH_PE_PRI_BUS, true);
730 pci_hp_add_devices(bus);
733 eeh_pe_state_clear(pe, EEH_PE_KEEP, true);
736 pe->freeze_count = cnt;
738 pci_unlock_rescan_remove();
742 /* The longest amount of time to wait for a pci device
743 * to come back on line, in seconds.
745 #define MAX_WAIT_FOR_RECOVERY 300
748 * eeh_handle_normal_event - Handle EEH events on a specific PE
749 * @pe: EEH PE - which should not be used after we return, as it may
750 * have been invalidated.
752 * Attempts to recover the given PE. If recovery fails or the PE has failed
753 * too many times, remove the PE.
755 * While PHB detects address or data parity errors on particular PCI
756 * slot, the associated PE will be frozen. Besides, DMA's occurring
757 * to wild addresses (which usually happen due to bugs in device
758 * drivers or in PCI adapter firmware) can cause EEH error. #SERR,
759 * #PERR or other misc PCI-related errors also can trigger EEH errors.
761 * Recovery process consists of unplugging the device driver (which
762 * generated hotplug events to userspace), then issuing a PCI #RST to
763 * the device, then reconfiguring the PCI config space for all bridges
764 * & devices under this slot, and then finally restarting the device
765 * drivers (which cause a second set of hotplug events to go out to
768 void eeh_handle_normal_event(struct eeh_pe *pe)
771 struct eeh_dev *edev, *tmp;
772 struct eeh_pe *tmp_pe;
774 enum pci_ers_result result = PCI_ERS_RESULT_NONE;
775 struct eeh_rmv_data rmv_data =
776 {LIST_HEAD_INIT(rmv_data.removed_vf_list), 0};
778 bus = eeh_pe_bus_get(pe);
780 pr_err("%s: Cannot find PCI bus for PHB#%x-PE#%x\n",
781 __func__, pe->phb->global_number, pe->addr);
785 eeh_pe_state_mark(pe, EEH_PE_RECOVERING);
787 eeh_pe_update_time_stamp(pe);
789 if (pe->freeze_count > eeh_max_freezes) {
790 pr_err("EEH: PHB#%x-PE#%x has failed %d times in the last hour and has been permanently disabled.\n",
791 pe->phb->global_number, pe->addr,
793 result = PCI_ERS_RESULT_DISCONNECT;
796 /* Walk the various device drivers attached to this slot through
797 * a reset sequence, giving each an opportunity to do what it needs
798 * to accomplish the reset. Each child gets a report of the
799 * status ... if any child can't handle the reset, then the entire
800 * slot is dlpar removed and added.
802 * When the PHB is fenced, we have to issue a reset to recover from
803 * the error. Override the result if necessary to have partially
804 * hotplug for this case.
806 if (result != PCI_ERS_RESULT_DISCONNECT) {
807 pr_warn("EEH: This PCI device has failed %d times in the last hour and will be permanently disabled after %d failures.\n",
808 pe->freeze_count, eeh_max_freezes);
809 pr_info("EEH: Notify device drivers to shutdown\n");
810 eeh_set_channel_state(pe, pci_channel_io_frozen);
811 eeh_set_irq_state(pe, false);
812 eeh_pe_report("error_detected(IO frozen)", pe,
813 eeh_report_error, &result);
814 if ((pe->type & EEH_PE_PHB) &&
815 result != PCI_ERS_RESULT_NONE &&
816 result != PCI_ERS_RESULT_NEED_RESET)
817 result = PCI_ERS_RESULT_NEED_RESET;
820 /* Get the current PCI slot state. This can take a long time,
821 * sometimes over 300 seconds for certain systems.
823 if (result != PCI_ERS_RESULT_DISCONNECT) {
824 rc = eeh_wait_state(pe, MAX_WAIT_FOR_RECOVERY*1000);
825 if (rc < 0 || rc == EEH_STATE_NOT_SUPPORT) {
826 pr_warn("EEH: Permanent failure\n");
827 result = PCI_ERS_RESULT_DISCONNECT;
831 /* Since rtas may enable MMIO when posting the error log,
832 * don't post the error log until after all dev drivers
833 * have been informed.
835 if (result != PCI_ERS_RESULT_DISCONNECT) {
836 pr_info("EEH: Collect temporary log\n");
837 eeh_slot_error_detail(pe, EEH_LOG_TEMP);
840 /* If all device drivers were EEH-unaware, then shut
841 * down all of the device drivers, and hope they
842 * go down willingly, without panicing the system.
844 if (result == PCI_ERS_RESULT_NONE) {
845 pr_info("EEH: Reset with hotplug activity\n");
846 rc = eeh_reset_device(pe, bus, NULL, false);
848 pr_warn("%s: Unable to reset, err=%d\n",
850 result = PCI_ERS_RESULT_DISCONNECT;
854 /* If all devices reported they can proceed, then re-enable MMIO */
855 if (result == PCI_ERS_RESULT_CAN_RECOVER) {
856 pr_info("EEH: Enable I/O for affected devices\n");
857 rc = eeh_pci_enable(pe, EEH_OPT_THAW_MMIO);
860 result = PCI_ERS_RESULT_DISCONNECT;
862 result = PCI_ERS_RESULT_NEED_RESET;
864 pr_info("EEH: Notify device drivers to resume I/O\n");
865 eeh_pe_report("mmio_enabled", pe,
866 eeh_report_mmio_enabled, &result);
870 /* If all devices reported they can proceed, then re-enable DMA */
871 if (result == PCI_ERS_RESULT_CAN_RECOVER) {
872 pr_info("EEH: Enabled DMA for affected devices\n");
873 rc = eeh_pci_enable(pe, EEH_OPT_THAW_DMA);
876 result = PCI_ERS_RESULT_DISCONNECT;
878 result = PCI_ERS_RESULT_NEED_RESET;
881 * We didn't do PE reset for the case. The PE
882 * is still in frozen state. Clear it before
885 eeh_pe_state_clear(pe, EEH_PE_ISOLATED, true);
886 result = PCI_ERS_RESULT_RECOVERED;
890 /* If any device called out for a reset, then reset the slot */
891 if (result == PCI_ERS_RESULT_NEED_RESET) {
892 pr_info("EEH: Reset without hotplug activity\n");
893 rc = eeh_reset_device(pe, bus, &rmv_data, true);
895 pr_warn("%s: Cannot reset, err=%d\n",
897 result = PCI_ERS_RESULT_DISCONNECT;
899 result = PCI_ERS_RESULT_NONE;
900 eeh_set_channel_state(pe, pci_channel_io_normal);
901 eeh_set_irq_state(pe, true);
902 eeh_pe_report("slot_reset", pe, eeh_report_reset,
907 if ((result == PCI_ERS_RESULT_RECOVERED) ||
908 (result == PCI_ERS_RESULT_NONE)) {
910 * For those hot removed VFs, we should add back them after PF
911 * get recovered properly.
913 list_for_each_entry_safe(edev, tmp, &rmv_data.removed_vf_list,
915 eeh_add_virt_device(edev);
916 list_del(&edev->rmv_entry);
919 /* Tell all device drivers that they can resume operations */
920 pr_info("EEH: Notify device driver to resume\n");
921 eeh_set_channel_state(pe, pci_channel_io_normal);
922 eeh_set_irq_state(pe, true);
923 eeh_pe_report("resume", pe, eeh_report_resume, NULL);
924 eeh_for_each_pe(pe, tmp_pe) {
925 eeh_pe_for_each_dev(tmp_pe, edev, tmp) {
926 edev->mode &= ~EEH_DEV_NO_HANDLER;
927 edev->in_error = false;
931 pr_info("EEH: Recovery successful.\n");
934 * About 90% of all real-life EEH failures in the field
935 * are due to poorly seated PCI cards. Only 10% or so are
936 * due to actual, failed cards.
938 pr_err("EEH: Unable to recover from failure from PHB#%x-PE#%x.\n"
939 "Please try reseating or replacing it\n",
940 pe->phb->global_number, pe->addr);
942 eeh_slot_error_detail(pe, EEH_LOG_PERM);
944 /* Notify all devices that they're about to go down. */
945 eeh_set_channel_state(pe, pci_channel_io_perm_failure);
946 eeh_set_irq_state(pe, false);
947 eeh_pe_report("error_detected(permanent failure)", pe,
948 eeh_report_failure, NULL);
950 /* Mark the PE to be removed permanently */
951 eeh_pe_state_mark(pe, EEH_PE_REMOVED);
954 * Shut down the device drivers for good. We mark
955 * all removed devices correctly to avoid access
956 * the their PCI config any more.
958 if (pe->type & EEH_PE_VF) {
959 eeh_pe_dev_traverse(pe, eeh_rmv_device, NULL);
960 eeh_pe_dev_mode_mark(pe, EEH_DEV_REMOVED);
962 eeh_pe_state_clear(pe, EEH_PE_PRI_BUS, true);
963 eeh_pe_dev_mode_mark(pe, EEH_DEV_REMOVED);
965 pci_lock_rescan_remove();
966 pci_hp_remove_devices(bus);
967 pci_unlock_rescan_remove();
968 /* The passed PE should no longer be used */
972 eeh_pe_state_clear(pe, EEH_PE_RECOVERING, true);
976 * eeh_handle_special_event - Handle EEH events without a specific failing PE
978 * Called when an EEH event is detected but can't be narrowed down to a
979 * specific PE. Iterates through possible failures and handles them as
982 void eeh_handle_special_event(void)
984 struct eeh_pe *pe, *phb_pe;
986 struct pci_controller *hose;
992 rc = eeh_ops->next_error(&pe);
995 case EEH_NEXT_ERR_DEAD_IOC:
996 /* Mark all PHBs in dead state */
997 eeh_serialize_lock(&flags);
999 /* Purge all events */
1000 eeh_remove_event(NULL, true);
1002 list_for_each_entry(hose, &hose_list, list_node) {
1003 phb_pe = eeh_phb_pe_get(hose);
1004 if (!phb_pe) continue;
1006 eeh_pe_mark_isolated(phb_pe);
1009 eeh_serialize_unlock(flags);
1012 case EEH_NEXT_ERR_FROZEN_PE:
1013 case EEH_NEXT_ERR_FENCED_PHB:
1014 case EEH_NEXT_ERR_DEAD_PHB:
1015 /* Mark the PE in fenced state */
1016 eeh_serialize_lock(&flags);
1018 /* Purge all events of the PHB */
1019 eeh_remove_event(pe, true);
1021 if (rc != EEH_NEXT_ERR_DEAD_PHB)
1022 eeh_pe_state_mark(pe, EEH_PE_RECOVERING);
1023 eeh_pe_mark_isolated(pe);
1025 eeh_serialize_unlock(flags);
1028 case EEH_NEXT_ERR_NONE:
1031 pr_warn("%s: Invalid value %d from next_error()\n",
1037 * For fenced PHB and frozen PE, it's handled as normal
1038 * event. We have to remove the affected PHBs for dead
1041 if (rc == EEH_NEXT_ERR_FROZEN_PE ||
1042 rc == EEH_NEXT_ERR_FENCED_PHB) {
1043 eeh_handle_normal_event(pe);
1045 pci_lock_rescan_remove();
1046 list_for_each_entry(hose, &hose_list, list_node) {
1047 phb_pe = eeh_phb_pe_get(hose);
1049 !(phb_pe->state & EEH_PE_ISOLATED) ||
1050 (phb_pe->state & EEH_PE_RECOVERING))
1053 /* Notify all devices to be down */
1054 eeh_pe_state_clear(pe, EEH_PE_PRI_BUS, true);
1055 eeh_set_channel_state(pe, pci_channel_io_perm_failure);
1057 "error_detected(permanent failure)", pe,
1058 eeh_report_failure, NULL);
1059 bus = eeh_pe_bus_get(phb_pe);
1061 pr_err("%s: Cannot find PCI bus for "
1064 pe->phb->global_number,
1068 pci_hp_remove_devices(bus);
1070 pci_unlock_rescan_remove();
1074 * If we have detected dead IOC, we needn't proceed
1075 * any more since all PHBs would have been removed
1077 if (rc == EEH_NEXT_ERR_DEAD_IOC)
1079 } while (rc != EEH_NEXT_ERR_NONE);