diff options
Diffstat (limited to 'arch/powerpc/platforms/pseries/eeh_driver.c')
| -rw-r--r-- | arch/powerpc/platforms/pseries/eeh_driver.c | 511 |
1 files changed, 511 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/pseries/eeh_driver.c b/arch/powerpc/platforms/pseries/eeh_driver.c new file mode 100644 index 00000000..1b6cb105 --- /dev/null +++ b/arch/powerpc/platforms/pseries/eeh_driver.c @@ -0,0 +1,511 @@ +/* + * PCI Error Recovery Driver for RPA-compliant PPC64 platform. + * Copyright IBM Corp. 2004 2005 + * Copyright Linas Vepstas <linas@linas.org> 2004, 2005 + * + * 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 comments and feedback to Linas Vepstas <linas@austin.ibm.com> + */ +#include <linux/delay.h> +#include <linux/interrupt.h> +#include <linux/irq.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 && pdev->dev.driver) + return pdev->dev.driver->name; + return ""; +} + +#if 0 +static void print_device_node_tree(struct pci_dn *pdn, int dent) +{ + int i; + struct device_node *pc; + + 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; + pc = pdn->node->child; + while (pc) { + print_device_node_tree(PCI_DN(pc), dent); + pc = pc->sibling; + } +} +#endif + +/** + * eeh_disable_irq - disable interrupt for the recovering device + */ +static void eeh_disable_irq(struct pci_dev *dev) +{ + struct device_node *dn = pci_device_to_OF_node(dev); + + /* Don't disable MSI and MSI-X interrupts. They are + * effectively disabled by the DMA Stopped state + * when an EEH error occurs. + */ + if (dev->msi_enabled || dev->msix_enabled) + return; + + if (!irq_has_action(dev->irq)) + return; + + PCI_DN(dn)->eeh_mode |= EEH_MODE_IRQ_DISABLED; + disable_irq_nosync(dev->irq); +} + +/** + * eeh_enable_irq - enable interrupt for the recovering device + */ +static void eeh_enable_irq(struct pci_dev *dev) +{ + struct device_node *dn = pci_device_to_OF_node(dev); + + if ((PCI_DN(dn)->eeh_mode) & EEH_MODE_IRQ_DISABLED) { + PCI_DN(dn)->eeh_mode &= ~EEH_MODE_IRQ_DISABLED; + enable_irq(dev->irq); + } +} + +/* ------------------------------------------------------- */ +/** + * eeh_report_error - report pci error to each device driver + * + * Report an EEH error to each device driver, collect up and + * merge the device driver responses. Cumulative response + * passed back in "userdata". + */ + +static int 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 0; + + eeh_disable_irq(dev); + + if (!driver->err_handler || + !driver->err_handler->error_detected) + return 0; + + rc = driver->err_handler->error_detected (dev, pci_channel_io_frozen); + + /* A driver that needs a reset trumps all others */ + if (rc == PCI_ERS_RESULT_NEED_RESET) *res = rc; + if (*res == PCI_ERS_RESULT_NONE) *res = rc; + + return 0; +} + +/** + * eeh_report_mmio_enabled - tell drivers that MMIO has been enabled + * + * Tells each device driver that IO ports, MMIO and config space I/O + * are now enabled. Collects up and merges the device driver responses. + * Cumulative response passed back in "userdata". + */ + +static int eeh_report_mmio_enabled(struct pci_dev *dev, void *userdata) +{ + enum pci_ers_result rc, *res = userdata; + struct pci_driver *driver = dev->driver; + + if (!driver || + !driver->err_handler || + !driver->err_handler->mmio_enabled) + return 0; + + rc = driver->err_handler->mmio_enabled (dev); + + /* A driver that needs a reset trumps all others */ + if (rc == PCI_ERS_RESULT_NEED_RESET) *res = rc; + if (*res == PCI_ERS_RESULT_NONE) *res = rc; + + return 0; +} + +/** + * eeh_report_reset - tell device that slot has been reset + */ + +static int eeh_report_reset(struct pci_dev *dev, void *userdata) +{ + enum pci_ers_result rc, *res = userdata; + struct pci_driver *driver = dev->driver; + + if (!driver) + return 0; + + dev->error_state = pci_channel_io_normal; + + eeh_enable_irq(dev); + + if (!driver->err_handler || + !driver->err_handler->slot_reset) + return 0; + + rc = driver->err_handler->slot_reset(dev); + if ((*res == PCI_ERS_RESULT_NONE) || + (*res == PCI_ERS_RESULT_RECOVERED)) *res = rc; + if (*res == PCI_ERS_RESULT_DISCONNECT && + rc == PCI_ERS_RESULT_NEED_RESET) *res = rc; + + return 0; +} + +/** + * eeh_report_resume - tell device to resume normal operations + */ + +static int 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 0; + + eeh_enable_irq(dev); + + if (!driver->err_handler || + !driver->err_handler->resume) + return 0; + + driver->err_handler->resume(dev); + + return 0; +} + +/** + * eeh_report_failure - tell device driver that device is dead. + * + * This informs the device driver that the device is permanently + * dead, and that no further recovery attempts will be made on it. + */ + +static int 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 0; + + eeh_disable_irq(dev); + + if (!driver->err_handler || + !driver->err_handler->error_detected) + return 0; + + driver->err_handler->error_detected(dev, pci_channel_io_perm_failure); + + return 0; +} + +/* ------------------------------------------------------- */ +/** + * 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 + * occurring 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 + * @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) +{ + struct device_node *dn; + int cnt, rc; + + /* pcibios will clear the counter; save the value */ + cnt = pe_dn->eeh_freeze_count; + + 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; + + /* Walk over all functions on this device. */ + dn = pe_dn->node; + if (!pcibios_find_pci_bus(dn) && PCI_DN(dn->parent)) + dn = dn->parent->child; + + while (dn) { + struct pci_dn *ppe = PCI_DN(dn); + /* On Power4, always true because eeh_pe_config_addr=0 */ + if (pe_dn->eeh_pe_config_addr == ppe->eeh_pe_config_addr) { + rtas_configure_bridge(ppe); + eeh_restore_bars(ppe); + } + dn = dn->sibling; + } + + /* 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); + } + pe_dn->eeh_freeze_count = cnt; + + 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 150 + +struct pci_dn * 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; + const char *location, *pci_str, *drv_str, *bus_pci_str, *bus_drv_str; + + frozen_dn = find_device_pe(event->dn); + if (!frozen_dn) { + + location = of_get_property(event->dn, "ibm,loc-code", NULL); + location = location ? location : "unknown"; + printk(KERN_ERR "EEH: Error: Cannot find partition endpoint " + "for location=%s pci addr=%s\n", + location, eeh_pci_name(event->dev)); + return NULL; + } + + frozen_bus = pcibios_find_pci_bus(frozen_dn); + location = of_get_property(frozen_dn, "ibm,loc-code", NULL); + location = location ? location : "unknown"; + + /* 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 location=%s dn=%s\n", + location, frozen_dn->full_name); + return NULL; + } + + frozen_pdn = PCI_DN(frozen_dn); + frozen_pdn->eeh_freeze_count++; + + pci_str = eeh_pci_name(event->dev); + drv_str = pcid_name(event->dev); + + if (frozen_pdn->eeh_freeze_count > EEH_MAX_ALLOWED_FREEZES) + goto excess_failures; + + printk(KERN_WARNING + "EEH: This PCI device has failed %d times in the last hour:\n", + frozen_pdn->eeh_freeze_count); + + if (frozen_pdn->pcidev) { + bus_pci_str = pci_name(frozen_pdn->pcidev); + bus_drv_str = pcid_name(frozen_pdn->pcidev); + printk(KERN_WARNING + "EEH: Bus location=%s driver=%s pci addr=%s\n", + location, bus_drv_str, bus_pci_str); + } + + printk(KERN_WARNING + "EEH: Device location=%s driver=%s pci addr=%s\n", + location, drv_str, pci_str); + + /* 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); + + /* Get the current PCI slot state. This can take a long time, + * sometimes over 3 seconds for certain systems. */ + rc = eeh_wait_for_slot_status (frozen_pdn, MAX_WAIT_FOR_RECOVERY*1000); + if (rc < 0) { + printk(KERN_WARNING "EEH: Permanent failure\n"); + goto hard_fail; + } + + /* Since rtas may enable MMIO when posting the error log, + * don't post the error log until after all dev drivers + * have been informed. + */ + eeh_slot_error_detail(frozen_pdn, EEH_LOG_TEMP_FAILURE); + + /* 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) { + printk(KERN_WARNING "EEH: Unable to reset, rc=%d\n", rc); + goto hard_fail; + } + } + + /* If all devices reported they can proceed, then re-enable MMIO */ + if (result == PCI_ERS_RESULT_CAN_RECOVER) { + rc = rtas_pci_enable(frozen_pdn, EEH_THAW_MMIO); + + if (rc < 0) + goto hard_fail; + if (rc) { + result = PCI_ERS_RESULT_NEED_RESET; + } else { + result = PCI_ERS_RESULT_NONE; + pci_walk_bus(frozen_bus, eeh_report_mmio_enabled, &result); + } + } + + /* If all devices reported they can proceed, then re-enable DMA */ + if (result == PCI_ERS_RESULT_CAN_RECOVER) { + rc = rtas_pci_enable(frozen_pdn, EEH_THAW_DMA); + + if (rc < 0) + goto hard_fail; + if (rc) + result = PCI_ERS_RESULT_NEED_RESET; + else + result = PCI_ERS_RESULT_RECOVERED; + } + + /* If any device has a hard failure, then shut off everything. */ + if (result == PCI_ERS_RESULT_DISCONNECT) { + printk(KERN_WARNING "EEH: Device driver gave up\n"); + 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) { + printk(KERN_WARNING "EEH: Cannot reset, rc=%d\n", rc); + goto hard_fail; + } + result = PCI_ERS_RESULT_NONE; + pci_walk_bus(frozen_bus, eeh_report_reset, &result); + } + + /* All devices should claim they have recovered by now. */ + if ((result != PCI_ERS_RESULT_RECOVERED) && + (result != PCI_ERS_RESULT_NONE)) { + printk(KERN_WARNING "EEH: Not recovered\n"); + goto hard_fail; + } + + /* Tell all device drivers that they can resume operations */ + pci_walk_bus(frozen_bus, eeh_report_resume, NULL); + + return frozen_pdn; + +excess_failures: + /* + * 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 at location=%s driver=%s pci addr=%s\n" + "has failed %d times in the last hour " + "and has been permanently disabled.\n" + "Please try reseating this device or replacing it.\n", + location, drv_str, pci_str, frozen_pdn->eeh_freeze_count); + goto perm_error; + +hard_fail: + printk(KERN_ERR + "EEH: Unable to recover from failure of PCI device " + "at location=%s driver=%s pci addr=%s\n" + "Please try reseating this device or replacing it.\n", + location, drv_str, pci_str); + +perm_error: + eeh_slot_error_detail(frozen_pdn, EEH_LOG_PERM_FAILURE); + + /* Notify all devices that they're about to go down. */ + pci_walk_bus(frozen_bus, eeh_report_failure, NULL); + + /* Shut down the device drivers for good. */ + pcibios_remove_pci_devices(frozen_bus); + + return NULL; +} + +/* ---------- end of file ---------- */ |