| /* |
| * PCI Error Recovery Driver for RPA-compliant PPC64 platform. |
| * Copyright (C) 2004, 2005 Linas Vepstas <linas@linas.org> |
| * |
| * All rights reserved. |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; either version 2 of the License, or (at |
| * your option) any later version. |
| * |
| * This program is distributed in the hope that it will be useful, but |
| * WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or |
| * NON INFRINGEMENT. See the GNU General Public License for more |
| * details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program; if not, write to the Free Software |
| * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. |
| * |
| * Send feedback to <linas@us.ibm.com> |
| * |
| */ |
| #include <linux/delay.h> |
| #include <linux/irq.h> |
| #include <linux/interrupt.h> |
| #include <linux/notifier.h> |
| #include <linux/pci.h> |
| #include <asm/eeh.h> |
| #include <asm/eeh_event.h> |
| #include <asm/ppc-pci.h> |
| #include <asm/pci-bridge.h> |
| #include <asm/prom.h> |
| #include <asm/rtas.h> |
| |
| |
| static inline const char * pcid_name (struct pci_dev *pdev) |
| { |
| if (pdev->dev.driver) |
| return pdev->dev.driver->name; |
| return ""; |
| } |
| |
| #ifdef DEBUG |
| static void print_device_node_tree (struct pci_dn *pdn, int dent) |
| { |
| int i; |
| if (!pdn) return; |
| for (i=0;i<dent; i++) |
| printk(" "); |
| printk("dn=%s mode=%x \tcfg_addr=%x pe_addr=%x \tfull=%s\n", |
| pdn->node->name, pdn->eeh_mode, pdn->eeh_config_addr, |
| pdn->eeh_pe_config_addr, pdn->node->full_name); |
| dent += 3; |
| struct device_node *pc = pdn->node->child; |
| while (pc) { |
| print_device_node_tree(PCI_DN(pc), dent); |
| pc = pc->sibling; |
| } |
| } |
| #endif |
| |
| /** |
| * irq_in_use - return true if this irq is being used |
| */ |
| static int irq_in_use(unsigned int irq) |
| { |
| int rc = 0; |
| unsigned long flags; |
| struct irq_desc *desc = irq_desc + irq; |
| |
| spin_lock_irqsave(&desc->lock, flags); |
| if (desc->action) |
| rc = 1; |
| spin_unlock_irqrestore(&desc->lock, flags); |
| return rc; |
| } |
| |
| /* ------------------------------------------------------- */ |
| /** eeh_report_error - report an EEH error to each device, |
| * collect up and merge the device responses. |
| */ |
| |
| static void eeh_report_error(struct pci_dev *dev, void *userdata) |
| { |
| enum pci_ers_result rc, *res = userdata; |
| struct pci_driver *driver = dev->driver; |
| |
| dev->error_state = pci_channel_io_frozen; |
| |
| if (!driver) |
| return; |
| |
| if (irq_in_use (dev->irq)) { |
| struct device_node *dn = pci_device_to_OF_node(dev); |
| PCI_DN(dn)->eeh_mode |= EEH_MODE_IRQ_DISABLED; |
| disable_irq_nosync(dev->irq); |
| } |
| if (!driver->err_handler) |
| return; |
| if (!driver->err_handler->error_detected) |
| return; |
| |
| rc = driver->err_handler->error_detected (dev, pci_channel_io_frozen); |
| if (*res == PCI_ERS_RESULT_NONE) *res = rc; |
| if (*res == PCI_ERS_RESULT_NEED_RESET) return; |
| if (*res == PCI_ERS_RESULT_DISCONNECT && |
| rc == PCI_ERS_RESULT_NEED_RESET) *res = rc; |
| } |
| |
| /** eeh_report_reset -- tell this device that the pci slot |
| * has been reset. |
| */ |
| |
| static void eeh_report_reset(struct pci_dev *dev, void *userdata) |
| { |
| struct pci_driver *driver = dev->driver; |
| struct device_node *dn = pci_device_to_OF_node(dev); |
| |
| if (!driver) |
| return; |
| |
| if ((PCI_DN(dn)->eeh_mode) & EEH_MODE_IRQ_DISABLED) { |
| PCI_DN(dn)->eeh_mode &= ~EEH_MODE_IRQ_DISABLED; |
| enable_irq(dev->irq); |
| } |
| if (!driver->err_handler) |
| return; |
| if (!driver->err_handler->slot_reset) |
| return; |
| |
| driver->err_handler->slot_reset(dev); |
| } |
| |
| static void eeh_report_resume(struct pci_dev *dev, void *userdata) |
| { |
| struct pci_driver *driver = dev->driver; |
| |
| dev->error_state = pci_channel_io_normal; |
| |
| if (!driver) |
| return; |
| if (!driver->err_handler) |
| return; |
| if (!driver->err_handler->resume) |
| return; |
| |
| driver->err_handler->resume(dev); |
| } |
| |
| static void eeh_report_failure(struct pci_dev *dev, void *userdata) |
| { |
| struct pci_driver *driver = dev->driver; |
| |
| dev->error_state = pci_channel_io_perm_failure; |
| |
| if (!driver) |
| return; |
| |
| if (irq_in_use (dev->irq)) { |
| struct device_node *dn = pci_device_to_OF_node(dev); |
| PCI_DN(dn)->eeh_mode |= EEH_MODE_IRQ_DISABLED; |
| disable_irq_nosync(dev->irq); |
| } |
| if (!driver->err_handler) |
| return; |
| if (!driver->err_handler->error_detected) |
| return; |
| driver->err_handler->error_detected(dev, pci_channel_io_perm_failure); |
| } |
| |
| /* ------------------------------------------------------- */ |
| /** |
| * handle_eeh_events -- reset a PCI device after hard lockup. |
| * |
| * pSeries systems will isolate a PCI slot if the PCI-Host |
| * bridge detects address or data parity errors, DMA's |
| * occuring to wild addresses (which usually happen due to |
| * bugs in device drivers or in PCI adapter firmware). |
| * Slot isolations also occur if #SERR, #PERR or other misc |
| * PCI-related errors are detected. |
| * |
| * Recovery process consists of unplugging the device driver |
| * (which generated hotplug events to userspace), then issuing |
| * a PCI #RST to the device, then reconfiguring the PCI config |
| * space for all bridges & devices under this slot, and then |
| * finally restarting the device drivers (which cause a second |
| * set of hotplug events to go out to userspace). |
| */ |
| |
| /** |
| * eeh_reset_device() -- perform actual reset of a pci slot |
| * Args: bus: pointer to the pci bus structure corresponding |
| * to the isolated slot. A non-null value will |
| * cause all devices under the bus to be removed |
| * and then re-added. |
| * pe_dn: pointer to a "Partionable Endpoint" device node. |
| * This is the top-level structure on which pci |
| * bus resets can be performed. |
| */ |
| |
| static int eeh_reset_device (struct pci_dn *pe_dn, struct pci_bus *bus) |
| { |
| int rc; |
| if (bus) |
| pcibios_remove_pci_devices(bus); |
| |
| /* Reset the pci controller. (Asserts RST#; resets config space). |
| * Reconfigure bridges and devices. Don't try to bring the system |
| * up if the reset failed for some reason. */ |
| rc = rtas_set_slot_reset(pe_dn); |
| if (rc) |
| return rc; |
| |
| /* New-style config addrs might be shared across multiple devices, |
| * Walk over all functions on this device */ |
| if (pe_dn->eeh_pe_config_addr) { |
| struct device_node *pe = pe_dn->node; |
| pe = pe->parent->child; |
| while (pe) { |
| struct pci_dn *ppe = PCI_DN(pe); |
| if (pe_dn->eeh_pe_config_addr == ppe->eeh_pe_config_addr) { |
| rtas_configure_bridge(ppe); |
| eeh_restore_bars(ppe); |
| } |
| pe = pe->sibling; |
| } |
| } else { |
| rtas_configure_bridge(pe_dn); |
| eeh_restore_bars(pe_dn); |
| } |
| |
| /* Give the system 5 seconds to finish running the user-space |
| * hotplug shutdown scripts, e.g. ifdown for ethernet. Yes, |
| * this is a hack, but if we don't do this, and try to bring |
| * the device up before the scripts have taken it down, |
| * potentially weird things happen. |
| */ |
| if (bus) { |
| ssleep (5); |
| pcibios_add_pci_devices(bus); |
| } |
| |
| return 0; |
| } |
| |
| /* The longest amount of time to wait for a pci device |
| * to come back on line, in seconds. |
| */ |
| #define MAX_WAIT_FOR_RECOVERY 15 |
| |
| void handle_eeh_events (struct eeh_event *event) |
| { |
| struct device_node *frozen_dn; |
| struct pci_dn *frozen_pdn; |
| struct pci_bus *frozen_bus; |
| int rc = 0; |
| enum pci_ers_result result = PCI_ERS_RESULT_NONE; |
| |
| frozen_dn = find_device_pe(event->dn); |
| frozen_bus = pcibios_find_pci_bus(frozen_dn); |
| |
| if (!frozen_dn) { |
| printk(KERN_ERR "EEH: Error: Cannot find partition endpoint for %s\n", |
| pci_name(event->dev)); |
| return; |
| } |
| |
| /* There are two different styles for coming up with the PE. |
| * In the old style, it was the highest EEH-capable device |
| * which was always an EADS pci bridge. In the new style, |
| * there might not be any EADS bridges, and even when there are, |
| * the firmware marks them as "EEH incapable". So another |
| * two-step is needed to find the pci bus.. */ |
| if (!frozen_bus) |
| frozen_bus = pcibios_find_pci_bus (frozen_dn->parent); |
| |
| if (!frozen_bus) { |
| printk(KERN_ERR "EEH: Cannot find PCI bus for %s\n", |
| frozen_dn->full_name); |
| return; |
| } |
| |
| #if 0 |
| /* We may get "permanent failure" messages on empty slots. |
| * These are false alarms. Empty slots have no child dn. */ |
| if ((event->state == pci_channel_io_perm_failure) && (frozen_device == NULL)) |
| return; |
| #endif |
| |
| frozen_pdn = PCI_DN(frozen_dn); |
| frozen_pdn->eeh_freeze_count++; |
| |
| if (frozen_pdn->eeh_freeze_count > EEH_MAX_ALLOWED_FREEZES) |
| goto hard_fail; |
| |
| /* If the reset state is a '5' and the time to reset is 0 (infinity) |
| * or is more then 15 seconds, then mark this as a permanent failure. |
| */ |
| if ((event->state == pci_channel_io_perm_failure) && |
| ((event->time_unavail <= 0) || |
| (event->time_unavail > MAX_WAIT_FOR_RECOVERY*1000))) |
| goto hard_fail; |
| |
| eeh_slot_error_detail(frozen_pdn, 1 /* Temporary Error */); |
| printk(KERN_WARNING |
| "EEH: This PCI device has failed %d times since last reboot: %s - %s\n", |
| frozen_pdn->eeh_freeze_count, |
| pci_name (frozen_pdn->pcidev), |
| pcid_name(frozen_pdn->pcidev)); |
| |
| /* Walk the various device drivers attached to this slot through |
| * a reset sequence, giving each an opportunity to do what it needs |
| * to accomplish the reset. Each child gets a report of the |
| * status ... if any child can't handle the reset, then the entire |
| * slot is dlpar removed and added. |
| */ |
| pci_walk_bus(frozen_bus, eeh_report_error, &result); |
| |
| /* If all device drivers were EEH-unaware, then shut |
| * down all of the device drivers, and hope they |
| * go down willingly, without panicing the system. |
| */ |
| if (result == PCI_ERS_RESULT_NONE) { |
| rc = eeh_reset_device(frozen_pdn, frozen_bus); |
| if (rc) |
| goto hard_fail; |
| } |
| |
| /* If any device called out for a reset, then reset the slot */ |
| if (result == PCI_ERS_RESULT_NEED_RESET) { |
| rc = eeh_reset_device(frozen_pdn, NULL); |
| if (rc) |
| goto hard_fail; |
| pci_walk_bus(frozen_bus, eeh_report_reset, 0); |
| } |
| |
| /* If all devices reported they can proceed, the re-enable PIO */ |
| if (result == PCI_ERS_RESULT_CAN_RECOVER) { |
| /* XXX Not supported; we brute-force reset the device */ |
| rc = eeh_reset_device(frozen_pdn, NULL); |
| if (rc) |
| goto hard_fail; |
| pci_walk_bus(frozen_bus, eeh_report_reset, 0); |
| } |
| |
| /* Tell all device drivers that they can resume operations */ |
| pci_walk_bus(frozen_bus, eeh_report_resume, 0); |
| |
| return; |
| |
| hard_fail: |
| /* |
| * About 90% of all real-life EEH failures in the field |
| * are due to poorly seated PCI cards. Only 10% or so are |
| * due to actual, failed cards. |
| */ |
| printk(KERN_ERR |
| "EEH: PCI device %s - %s has failed %d times \n" |
| "and has been permanently disabled. Please try reseating\n" |
| "this device or replacing it.\n", |
| pci_name (frozen_pdn->pcidev), |
| pcid_name(frozen_pdn->pcidev), |
| frozen_pdn->eeh_freeze_count); |
| |
| eeh_slot_error_detail(frozen_pdn, 2 /* Permanent Error */); |
| |
| /* Notify all devices that they're about to go down. */ |
| pci_walk_bus(frozen_bus, eeh_report_failure, 0); |
| |
| /* Shut down the device drivers for good. */ |
| pcibios_remove_pci_devices(frozen_bus); |
| } |
| |
| /* ---------- end of file ---------- */ |
