| Author | Tokens | Token Proportion | Commits | Commit Proportion |
|---|---|---|---|---|
| Gavin Shan | 3027 | 48.55% | 91 | 39.74% |
| Oliver O'Halloran | 1360 | 21.81% | 23 | 10.04% |
| Linas Vepstas | 810 | 12.99% | 32 | 13.97% |
| Sam Bobroff | 318 | 5.10% | 16 | 6.99% |
| Anton Blanchard | 136 | 2.18% | 5 | 2.18% |
| Andrew Morton | 130 | 2.09% | 4 | 1.75% |
| Paul Mackerras | 83 | 1.33% | 8 | 3.49% |
| Brian King | 60 | 0.96% | 2 | 0.87% |
| Russell Currey | 57 | 0.91% | 3 | 1.31% |
| Wei Yang | 46 | 0.74% | 3 | 1.31% |
| Benjamin Herrenschmidt | 39 | 0.63% | 6 | 2.62% |
| Mike Mason | 31 | 0.50% | 2 | 0.87% |
| Richard A. Lary | 26 | 0.42% | 2 | 0.87% |
| Uwe Kleine-König | 17 | 0.27% | 1 | 0.44% |
| Aneesh Kumar K.V | 12 | 0.19% | 2 | 0.87% |
| Thadeu Lima de Souza Cascardo | 8 | 0.13% | 2 | 0.87% |
| Alexey Kardashevskiy | 7 | 0.11% | 1 | 0.44% |
| Bryant G. Ly | 7 | 0.11% | 1 | 0.44% |
| Paul Gortmaker | 6 | 0.10% | 2 | 0.87% |
| Kai Song | 6 | 0.10% | 1 | 0.44% |
| Michael Ellerman | 6 | 0.10% | 1 | 0.44% |
| Stephen Rothwell | 5 | 0.08% | 2 | 0.87% |
| Mike Qiu | 5 | 0.08% | 1 | 0.44% |
| Thomas Gleixner | 3 | 0.05% | 2 | 0.87% |
| Linus Torvalds | 3 | 0.05% | 1 | 0.44% |
| David Gibson | 3 | 0.05% | 2 | 0.87% |
| Ganesh Goudar | 3 | 0.05% | 1 | 0.44% |
| Roland Dreier | 2 | 0.03% | 1 | 0.44% |
| Alistair Popple | 2 | 0.03% | 1 | 0.44% |
| Julia Lawall | 2 | 0.03% | 1 | 0.44% |
| Guilherme G. Piccoli | 2 | 0.03% | 1 | 0.44% |
| Denis V. Lunev | 2 | 0.03% | 1 | 0.44% |
| Yijing Wang | 2 | 0.03% | 1 | 0.44% |
| Christoph Hellwig | 2 | 0.03% | 1 | 0.44% |
| Yue haibing | 2 | 0.03% | 1 | 0.44% |
| Nicholas Piggin | 2 | 0.03% | 1 | 0.44% |
| Andrew Donnellan | 2 | 0.03% | 2 | 0.87% |
| Breno Leitão | 1 | 0.02% | 1 | 0.44% |
| Total | 6235 | 229 |
// SPDX-License-Identifier: GPL-2.0-or-later /* * Copyright IBM Corporation 2001, 2005, 2006 * Copyright Dave Engebretsen & Todd Inglett 2001 * Copyright Linas Vepstas 2005, 2006 * Copyright 2001-2012 IBM Corporation. * * Please address comments and feedback to Linas Vepstas <linas@austin.ibm.com> */ #include <linux/delay.h> #include <linux/sched.h> #include <linux/init.h> #include <linux/list.h> #include <linux/pci.h> #include <linux/iommu.h> #include <linux/proc_fs.h> #include <linux/rbtree.h> #include <linux/reboot.h> #include <linux/seq_file.h> #include <linux/spinlock.h> #include <linux/export.h> #include <linux/of.h> #include <linux/debugfs.h> #include <linux/atomic.h> #include <asm/eeh.h> #include <asm/eeh_event.h> #include <asm/io.h> #include <asm/iommu.h> #include <asm/machdep.h> #include <asm/ppc-pci.h> #include <asm/rtas.h> #include <asm/pte-walk.h> /** Overview: * EEH, or "Enhanced Error Handling" is a PCI bridge technology for * dealing with PCI bus errors that can't be dealt with within the * usual PCI framework, except by check-stopping the CPU. Systems * that are designed for high-availability/reliability cannot afford * to crash due to a "mere" PCI error, thus the need for EEH. * An EEH-capable bridge operates by converting a detected error * into a "slot freeze", taking the PCI adapter off-line, making * the slot behave, from the OS'es point of view, as if the slot * were "empty": all reads return 0xff's and all writes are silently * ignored. EEH slot isolation events can be triggered by parity * errors on the address or data busses (e.g. during posted writes), * which in turn might be caused by low voltage on the bus, dust, * vibration, humidity, radioactivity or plain-old failed hardware. * * Note, however, that one of the leading causes of EEH slot * freeze events are buggy device drivers, buggy device microcode, * or buggy device hardware. This is because any attempt by the * device to bus-master data to a memory address that is not * assigned to the device will trigger a slot freeze. (The idea * is to prevent devices-gone-wild from corrupting system memory). * Buggy hardware/drivers will have a miserable time co-existing * with EEH. * * Ideally, a PCI device driver, when suspecting that an isolation * event has occurred (e.g. by reading 0xff's), will then ask EEH * whether this is the case, and then take appropriate steps to * reset the PCI slot, the PCI device, and then resume operations. * However, until that day, the checking is done here, with the * eeh_check_failure() routine embedded in the MMIO macros. If * the slot is found to be isolated, an "EEH Event" is synthesized * and sent out for processing. */ /* If a device driver keeps reading an MMIO register in an interrupt * handler after a slot isolation event, it might be broken. * This sets the threshold for how many read attempts we allow * before printing an error message. */ #define EEH_MAX_FAILS 2100000 /* Time to wait for a PCI slot to report status, in milliseconds */ #define PCI_BUS_RESET_WAIT_MSEC (5*60*1000) /* * EEH probe mode support, which is part of the flags, * is to support multiple platforms for EEH. Some platforms * like pSeries do PCI emunation based on device tree. * However, other platforms like powernv probe PCI devices * from hardware. The flag is used to distinguish that. * In addition, struct eeh_ops::probe would be invoked for * particular OF node or PCI device so that the corresponding * PE would be created there. */ int eeh_subsystem_flags; EXPORT_SYMBOL(eeh_subsystem_flags); /* * EEH allowed maximal frozen times. If one particular PE's * frozen count in last hour exceeds this limit, the PE will * be forced to be offline permanently. */ u32 eeh_max_freezes = 5; /* * Controls whether a recovery event should be scheduled when an * isolated device is discovered. This is only really useful for * debugging problems with the EEH core. */ bool eeh_debugfs_no_recover; /* Platform dependent EEH operations */ struct eeh_ops *eeh_ops = NULL; /* Lock to avoid races due to multiple reports of an error */ DEFINE_RAW_SPINLOCK(confirm_error_lock); EXPORT_SYMBOL_GPL(confirm_error_lock); /* Lock to protect passed flags */ static DEFINE_MUTEX(eeh_dev_mutex); /* Buffer for reporting pci register dumps. Its here in BSS, and * not dynamically alloced, so that it ends up in RMO where RTAS * can access it. */ #define EEH_PCI_REGS_LOG_LEN 8192 static unsigned char pci_regs_buf[EEH_PCI_REGS_LOG_LEN]; /* * The struct is used to maintain the EEH global statistic * information. Besides, the EEH global statistics will be * exported to user space through procfs */ struct eeh_stats { u64 no_device; /* PCI device not found */ u64 no_dn; /* OF node not found */ u64 no_cfg_addr; /* Config address not found */ u64 ignored_check; /* EEH check skipped */ u64 total_mmio_ffs; /* Total EEH checks */ u64 false_positives; /* Unnecessary EEH checks */ u64 slot_resets; /* PE reset */ }; static struct eeh_stats eeh_stats; static int __init eeh_setup(char *str) { if (!strcmp(str, "off")) eeh_add_flag(EEH_FORCE_DISABLED); else if (!strcmp(str, "early_log")) eeh_add_flag(EEH_EARLY_DUMP_LOG); return 1; } __setup("eeh=", eeh_setup); void eeh_show_enabled(void) { if (eeh_has_flag(EEH_FORCE_DISABLED)) pr_info("EEH: Recovery disabled by kernel parameter.\n"); else if (eeh_has_flag(EEH_ENABLED)) pr_info("EEH: Capable adapter found: recovery enabled.\n"); else pr_info("EEH: No capable adapters found: recovery disabled.\n"); } /* * This routine captures assorted PCI configuration space data * for the indicated PCI device, and puts them into a buffer * for RTAS error logging. */ static size_t eeh_dump_dev_log(struct eeh_dev *edev, char *buf, size_t len) { u32 cfg; int cap, i; int n = 0, l = 0; char buffer[128]; n += scnprintf(buf+n, len-n, "%04x:%02x:%02x.%01x\n", edev->pe->phb->global_number, edev->bdfn >> 8, PCI_SLOT(edev->bdfn), PCI_FUNC(edev->bdfn)); pr_warn("EEH: of node=%04x:%02x:%02x.%01x\n", edev->pe->phb->global_number, edev->bdfn >> 8, PCI_SLOT(edev->bdfn), PCI_FUNC(edev->bdfn)); eeh_ops->read_config(edev, PCI_VENDOR_ID, 4, &cfg); n += scnprintf(buf+n, len-n, "dev/vend:%08x\n", cfg); pr_warn("EEH: PCI device/vendor: %08x\n", cfg); eeh_ops->read_config(edev, PCI_COMMAND, 4, &cfg); n += scnprintf(buf+n, len-n, "cmd/stat:%x\n", cfg); pr_warn("EEH: PCI cmd/status register: %08x\n", cfg); /* Gather bridge-specific registers */ if (edev->mode & EEH_DEV_BRIDGE) { eeh_ops->read_config(edev, PCI_SEC_STATUS, 2, &cfg); n += scnprintf(buf+n, len-n, "sec stat:%x\n", cfg); pr_warn("EEH: Bridge secondary status: %04x\n", cfg); eeh_ops->read_config(edev, PCI_BRIDGE_CONTROL, 2, &cfg); n += scnprintf(buf+n, len-n, "brdg ctl:%x\n", cfg); pr_warn("EEH: Bridge control: %04x\n", cfg); } /* Dump out the PCI-X command and status regs */ cap = edev->pcix_cap; if (cap) { eeh_ops->read_config(edev, cap, 4, &cfg); n += scnprintf(buf+n, len-n, "pcix-cmd:%x\n", cfg); pr_warn("EEH: PCI-X cmd: %08x\n", cfg); eeh_ops->read_config(edev, cap+4, 4, &cfg); n += scnprintf(buf+n, len-n, "pcix-stat:%x\n", cfg); pr_warn("EEH: PCI-X status: %08x\n", cfg); } /* If PCI-E capable, dump PCI-E cap 10 */ cap = edev->pcie_cap; if (cap) { n += scnprintf(buf+n, len-n, "pci-e cap10:\n"); pr_warn("EEH: PCI-E capabilities and status follow:\n"); for (i=0; i<=8; i++) { eeh_ops->read_config(edev, cap+4*i, 4, &cfg); n += scnprintf(buf+n, len-n, "%02x:%x\n", 4*i, cfg); if ((i % 4) == 0) { if (i != 0) pr_warn("%s\n", buffer); l = scnprintf(buffer, sizeof(buffer), "EEH: PCI-E %02x: %08x ", 4*i, cfg); } else { l += scnprintf(buffer+l, sizeof(buffer)-l, "%08x ", cfg); } } pr_warn("%s\n", buffer); } /* If AER capable, dump it */ cap = edev->aer_cap; if (cap) { n += scnprintf(buf+n, len-n, "pci-e AER:\n"); pr_warn("EEH: PCI-E AER capability register set follows:\n"); for (i=0; i<=13; i++) { eeh_ops->read_config(edev, cap+4*i, 4, &cfg); n += scnprintf(buf+n, len-n, "%02x:%x\n", 4*i, cfg); if ((i % 4) == 0) { if (i != 0) pr_warn("%s\n", buffer); l = scnprintf(buffer, sizeof(buffer), "EEH: PCI-E AER %02x: %08x ", 4*i, cfg); } else { l += scnprintf(buffer+l, sizeof(buffer)-l, "%08x ", cfg); } } pr_warn("%s\n", buffer); } return n; } static void *eeh_dump_pe_log(struct eeh_pe *pe, void *flag) { struct eeh_dev *edev, *tmp; size_t *plen = flag; eeh_pe_for_each_dev(pe, edev, tmp) *plen += eeh_dump_dev_log(edev, pci_regs_buf + *plen, EEH_PCI_REGS_LOG_LEN - *plen); return NULL; } /** * eeh_slot_error_detail - Generate combined log including driver log and error log * @pe: EEH PE * @severity: temporary or permanent error log * * This routine should be called to generate the combined log, which * is comprised of driver log and error log. The driver log is figured * out from the config space of the corresponding PCI device, while * the error log is fetched through platform dependent function call. */ void eeh_slot_error_detail(struct eeh_pe *pe, int severity) { size_t loglen = 0; /* * When the PHB is fenced or dead, it's pointless to collect * the data from PCI config space because it should return * 0xFF's. For ER, we still retrieve the data from the PCI * config space. * * For pHyp, we have to enable IO for log retrieval. Otherwise, * 0xFF's is always returned from PCI config space. * * When the @severity is EEH_LOG_PERM, the PE is going to be * removed. Prior to that, the drivers for devices included in * the PE will be closed. The drivers rely on working IO path * to bring the devices to quiet state. Otherwise, PCI traffic * from those devices after they are removed is like to cause * another unexpected EEH error. */ if (!(pe->type & EEH_PE_PHB)) { if (eeh_has_flag(EEH_ENABLE_IO_FOR_LOG) || severity == EEH_LOG_PERM) eeh_pci_enable(pe, EEH_OPT_THAW_MMIO); /* * The config space of some PCI devices can't be accessed * when their PEs are in frozen state. Otherwise, fenced * PHB might be seen. Those PEs are identified with flag * EEH_PE_CFG_RESTRICTED, indicating EEH_PE_CFG_BLOCKED * is set automatically when the PE is put to EEH_PE_ISOLATED. * * Restoring BARs possibly triggers PCI config access in * (OPAL) firmware and then causes fenced PHB. If the * PCI config is blocked with flag EEH_PE_CFG_BLOCKED, it's * pointless to restore BARs and dump config space. */ eeh_ops->configure_bridge(pe); if (!(pe->state & EEH_PE_CFG_BLOCKED)) { eeh_pe_restore_bars(pe); pci_regs_buf[0] = 0; eeh_pe_traverse(pe, eeh_dump_pe_log, &loglen); } } eeh_ops->get_log(pe, severity, pci_regs_buf, loglen); } /** * eeh_token_to_phys - Convert EEH address token to phys address * @token: I/O token, should be address in the form 0xA.... * * This routine should be called to convert virtual I/O address * to physical one. */ static inline unsigned long eeh_token_to_phys(unsigned long token) { return ppc_find_vmap_phys(token); } /* * On PowerNV platform, we might already have fenced PHB there. * For that case, it's meaningless to recover frozen PE. Intead, * We have to handle fenced PHB firstly. */ static int eeh_phb_check_failure(struct eeh_pe *pe) { struct eeh_pe *phb_pe; unsigned long flags; int ret; if (!eeh_has_flag(EEH_PROBE_MODE_DEV)) return -EPERM; /* Find the PHB PE */ phb_pe = eeh_phb_pe_get(pe->phb); if (!phb_pe) { pr_warn("%s Can't find PE for PHB#%x\n", __func__, pe->phb->global_number); return -EEXIST; } /* If the PHB has been in problematic state */ eeh_serialize_lock(&flags); if (phb_pe->state & EEH_PE_ISOLATED) { ret = 0; goto out; } /* Check PHB state */ ret = eeh_ops->get_state(phb_pe, NULL); if ((ret < 0) || (ret == EEH_STATE_NOT_SUPPORT) || eeh_state_active(ret)) { ret = 0; goto out; } /* Isolate the PHB and send event */ eeh_pe_mark_isolated(phb_pe); eeh_serialize_unlock(flags); pr_debug("EEH: PHB#%x failure detected, location: %s\n", phb_pe->phb->global_number, eeh_pe_loc_get(phb_pe)); eeh_send_failure_event(phb_pe); return 1; out: eeh_serialize_unlock(flags); return ret; } static inline const char *eeh_driver_name(struct pci_dev *pdev) { if (pdev) return dev_driver_string(&pdev->dev); return "<null>"; } /** * eeh_dev_check_failure - Check if all 1's data is due to EEH slot freeze * @edev: eeh device * * Check for an EEH failure for the given device node. Call this * routine if the result of a read was all 0xff's and you want to * find out if this is due to an EEH slot freeze. This routine * will query firmware for the EEH status. * * Returns 0 if there has not been an EEH error; otherwise returns * a non-zero value and queues up a slot isolation event notification. * * It is safe to call this routine in an interrupt context. */ int eeh_dev_check_failure(struct eeh_dev *edev) { int ret; unsigned long flags; struct device_node *dn; struct pci_dev *dev; struct eeh_pe *pe, *parent_pe; int rc = 0; const char *location = NULL; eeh_stats.total_mmio_ffs++; if (!eeh_enabled()) return 0; if (!edev) { eeh_stats.no_dn++; return 0; } dev = eeh_dev_to_pci_dev(edev); pe = eeh_dev_to_pe(edev); /* Access to IO BARs might get this far and still not want checking. */ if (!pe) { eeh_stats.ignored_check++; eeh_edev_dbg(edev, "Ignored check\n"); return 0; } /* * On PowerNV platform, we might already have fenced PHB * there and we need take care of that firstly. */ ret = eeh_phb_check_failure(pe); if (ret > 0) return ret; /* * If the PE isn't owned by us, we shouldn't check the * state. Instead, let the owner handle it if the PE has * been frozen. */ if (eeh_pe_passed(pe)) return 0; /* If we already have a pending isolation event for this * slot, we know it's bad already, we don't need to check. * Do this checking under a lock; as multiple PCI devices * in one slot might report errors simultaneously, and we * only want one error recovery routine running. */ eeh_serialize_lock(&flags); rc = 1; if (pe->state & EEH_PE_ISOLATED) { pe->check_count++; if (pe->check_count == EEH_MAX_FAILS) { dn = pci_device_to_OF_node(dev); if (dn) location = of_get_property(dn, "ibm,loc-code", NULL); eeh_edev_err(edev, "%d reads ignored for recovering device at location=%s driver=%s\n", pe->check_count, location ? location : "unknown", eeh_driver_name(dev)); eeh_edev_err(edev, "Might be infinite loop in %s driver\n", eeh_driver_name(dev)); dump_stack(); } goto dn_unlock; } /* * Now test for an EEH failure. This is VERY expensive. * Note that the eeh_config_addr may be a parent device * in the case of a device behind a bridge, or it may be * function zero of a multi-function device. * In any case they must share a common PHB. */ ret = eeh_ops->get_state(pe, NULL); /* Note that config-io to empty slots may fail; * they are empty when they don't have children. * We will punt with the following conditions: Failure to get * PE's state, EEH not support and Permanently unavailable * state, PE is in good state. * * On the pSeries, after reaching the threshold, get_state might * return EEH_STATE_NOT_SUPPORT. However, it's possible that the * device state remains uncleared if the device is not marked * pci_channel_io_perm_failure. Therefore, consider logging the * event to let device removal happen. * */ if ((ret < 0) || (ret == EEH_STATE_NOT_SUPPORT && dev->error_state == pci_channel_io_perm_failure) || eeh_state_active(ret)) { eeh_stats.false_positives++; pe->false_positives++; rc = 0; goto dn_unlock; } /* * It should be corner case that the parent PE has been * put into frozen state as well. We should take care * that at first. */ parent_pe = pe->parent; while (parent_pe) { /* Hit the ceiling ? */ if (parent_pe->type & EEH_PE_PHB) break; /* Frozen parent PE ? */ ret = eeh_ops->get_state(parent_pe, NULL); if (ret > 0 && !eeh_state_active(ret)) { pe = parent_pe; pr_err("EEH: Failure of PHB#%x-PE#%x will be handled at parent PHB#%x-PE#%x.\n", pe->phb->global_number, pe->addr, pe->phb->global_number, parent_pe->addr); } /* Next parent level */ parent_pe = parent_pe->parent; } eeh_stats.slot_resets++; /* Avoid repeated reports of this failure, including problems * with other functions on this device, and functions under * bridges. */ eeh_pe_mark_isolated(pe); eeh_serialize_unlock(flags); /* Most EEH events are due to device driver bugs. Having * a stack trace will help the device-driver authors figure * out what happened. So print that out. */ pr_debug("EEH: %s: Frozen PHB#%x-PE#%x detected\n", __func__, pe->phb->global_number, pe->addr); eeh_send_failure_event(pe); return 1; dn_unlock: eeh_serialize_unlock(flags); return rc; } EXPORT_SYMBOL_GPL(eeh_dev_check_failure); /** * eeh_check_failure - Check if all 1's data is due to EEH slot freeze * @token: I/O address * * Check for an EEH failure at the given I/O address. Call this * routine if the result of a read was all 0xff's and you want to * find out if this is due to an EEH slot freeze event. This routine * will query firmware for the EEH status. * * Note this routine is safe to call in an interrupt context. */ int eeh_check_failure(const volatile void __iomem *token) { unsigned long addr; struct eeh_dev *edev; /* Finding the phys addr + pci device; this is pretty quick. */ addr = eeh_token_to_phys((unsigned long __force) token); edev = eeh_addr_cache_get_dev(addr); if (!edev) { eeh_stats.no_device++; return 0; } return eeh_dev_check_failure(edev); } EXPORT_SYMBOL(eeh_check_failure); /** * eeh_pci_enable - Enable MMIO or DMA transfers for this slot * @pe: EEH PE * @function: EEH option * * This routine should be called to reenable frozen MMIO or DMA * so that it would work correctly again. It's useful while doing * recovery or log collection on the indicated device. */ int eeh_pci_enable(struct eeh_pe *pe, int function) { int active_flag, rc; /* * pHyp doesn't allow to enable IO or DMA on unfrozen PE. * Also, it's pointless to enable them on unfrozen PE. So * we have to check before enabling IO or DMA. */ switch (function) { case EEH_OPT_THAW_MMIO: active_flag = EEH_STATE_MMIO_ACTIVE | EEH_STATE_MMIO_ENABLED; break; case EEH_OPT_THAW_DMA: active_flag = EEH_STATE_DMA_ACTIVE; break; case EEH_OPT_DISABLE: case EEH_OPT_ENABLE: case EEH_OPT_FREEZE_PE: active_flag = 0; break; default: pr_warn("%s: Invalid function %d\n", __func__, function); return -EINVAL; } /* * Check if IO or DMA has been enabled before * enabling them. */ if (active_flag) { rc = eeh_ops->get_state(pe, NULL); if (rc < 0) return rc; /* Needn't enable it at all */ if (rc == EEH_STATE_NOT_SUPPORT) return 0; /* It's already enabled */ if (rc & active_flag) return 0; } /* Issue the request */ rc = eeh_ops->set_option(pe, function); if (rc) pr_warn("%s: Unexpected state change %d on " "PHB#%x-PE#%x, err=%d\n", __func__, function, pe->phb->global_number, pe->addr, rc); /* Check if the request is finished successfully */ if (active_flag) { rc = eeh_wait_state(pe, PCI_BUS_RESET_WAIT_MSEC); if (rc < 0) return rc; if (rc & active_flag) return 0; return -EIO; } return rc; } static void eeh_disable_and_save_dev_state(struct eeh_dev *edev, void *userdata) { struct pci_dev *pdev = eeh_dev_to_pci_dev(edev); struct pci_dev *dev = userdata; /* * The caller should have disabled and saved the * state for the specified device */ if (!pdev || pdev == dev) return; /* Ensure we have D0 power state */ pci_set_power_state(pdev, PCI_D0); /* Save device state */ pci_save_state(pdev); /* * Disable device to avoid any DMA traffic and * interrupt from the device */ pci_write_config_word(pdev, PCI_COMMAND, PCI_COMMAND_INTX_DISABLE); } static void eeh_restore_dev_state(struct eeh_dev *edev, void *userdata) { struct pci_dev *pdev = eeh_dev_to_pci_dev(edev); struct pci_dev *dev = userdata; if (!pdev) return; /* Apply customization from firmware */ if (eeh_ops->restore_config) eeh_ops->restore_config(edev); /* The caller should restore state for the specified device */ if (pdev != dev) pci_restore_state(pdev); } /** * pcibios_set_pcie_reset_state - Set PCI-E reset state * @dev: pci device struct * @state: reset state to enter * * Return value: * 0 if success */ int pcibios_set_pcie_reset_state(struct pci_dev *dev, enum pcie_reset_state state) { struct eeh_dev *edev = pci_dev_to_eeh_dev(dev); struct eeh_pe *pe = eeh_dev_to_pe(edev); if (!pe) { pr_err("%s: No PE found on PCI device %s\n", __func__, pci_name(dev)); return -EINVAL; } switch (state) { case pcie_deassert_reset: eeh_ops->reset(pe, EEH_RESET_DEACTIVATE); eeh_unfreeze_pe(pe); if (!(pe->type & EEH_PE_VF)) eeh_pe_state_clear(pe, EEH_PE_CFG_BLOCKED, true); eeh_pe_dev_traverse(pe, eeh_restore_dev_state, dev); eeh_pe_state_clear(pe, EEH_PE_ISOLATED, true); break; case pcie_hot_reset: eeh_pe_mark_isolated(pe); eeh_pe_state_clear(pe, EEH_PE_CFG_BLOCKED, true); eeh_ops->set_option(pe, EEH_OPT_FREEZE_PE); eeh_pe_dev_traverse(pe, eeh_disable_and_save_dev_state, dev); if (!(pe->type & EEH_PE_VF)) eeh_pe_state_mark(pe, EEH_PE_CFG_BLOCKED); eeh_ops->reset(pe, EEH_RESET_HOT); break; case pcie_warm_reset: eeh_pe_mark_isolated(pe); eeh_pe_state_clear(pe, EEH_PE_CFG_BLOCKED, true); eeh_ops->set_option(pe, EEH_OPT_FREEZE_PE); eeh_pe_dev_traverse(pe, eeh_disable_and_save_dev_state, dev); if (!(pe->type & EEH_PE_VF)) eeh_pe_state_mark(pe, EEH_PE_CFG_BLOCKED); eeh_ops->reset(pe, EEH_RESET_FUNDAMENTAL); break; default: eeh_pe_state_clear(pe, EEH_PE_ISOLATED | EEH_PE_CFG_BLOCKED, true); return -EINVAL; } return 0; } /** * eeh_set_dev_freset - Check the required reset for the indicated device * @edev: EEH device * @flag: return value * * Each device might have its preferred reset type: fundamental or * hot reset. The routine is used to collected the information for * the indicated device and its children so that the bunch of the * devices could be reset properly. */ static void eeh_set_dev_freset(struct eeh_dev *edev, void *flag) { struct pci_dev *dev; unsigned int *freset = (unsigned int *)flag; dev = eeh_dev_to_pci_dev(edev); if (dev) *freset |= dev->needs_freset; } static void eeh_pe_refreeze_passed(struct eeh_pe *root) { struct eeh_pe *pe; int state; eeh_for_each_pe(root, pe) { if (eeh_pe_passed(pe)) { state = eeh_ops->get_state(pe, NULL); if (state & (EEH_STATE_MMIO_ACTIVE | EEH_STATE_MMIO_ENABLED)) { pr_info("EEH: Passed-through PE PHB#%x-PE#%x was thawed by reset, re-freezing for safety.\n", pe->phb->global_number, pe->addr); eeh_pe_set_option(pe, EEH_OPT_FREEZE_PE); } } } } /** * eeh_pe_reset_full - Complete a full reset process on the indicated PE * @pe: EEH PE * @include_passed: include passed-through devices? * * This function executes a full reset procedure on a PE, including setting * the appropriate flags, performing a fundamental or hot reset, and then * deactivating the reset status. It is designed to be used within the EEH * subsystem, as opposed to eeh_pe_reset which is exported to drivers and * only performs a single operation at a time. * * This function will attempt to reset a PE three times before failing. */ int eeh_pe_reset_full(struct eeh_pe *pe, bool include_passed) { int reset_state = (EEH_PE_RESET | EEH_PE_CFG_BLOCKED); int type = EEH_RESET_HOT; unsigned int freset = 0; int i, state = 0, ret; /* * Determine the type of reset to perform - hot or fundamental. * Hot reset is the default operation, unless any device under the * PE requires a fundamental reset. */ eeh_pe_dev_traverse(pe, eeh_set_dev_freset, &freset); if (freset) type = EEH_RESET_FUNDAMENTAL; /* Mark the PE as in reset state and block config space accesses */ eeh_pe_state_mark(pe, reset_state); /* Make three attempts at resetting the bus */ for (i = 0; i < 3; i++) { ret = eeh_pe_reset(pe, type, include_passed); if (!ret) ret = eeh_pe_reset(pe, EEH_RESET_DEACTIVATE, include_passed); if (ret) { ret = -EIO; pr_warn("EEH: Failure %d resetting PHB#%x-PE#%x (attempt %d)\n\n", state, pe->phb->global_number, pe->addr, i + 1); continue; } if (i) pr_warn("EEH: PHB#%x-PE#%x: Successful reset (attempt %d)\n", pe->phb->global_number, pe->addr, i + 1); /* Wait until the PE is in a functioning state */ state = eeh_wait_state(pe, PCI_BUS_RESET_WAIT_MSEC); if (state < 0) { pr_warn("EEH: Unrecoverable slot failure on PHB#%x-PE#%x", pe->phb->global_number, pe->addr); ret = -ENOTRECOVERABLE; break; } if (eeh_state_active(state)) break; else pr_warn("EEH: PHB#%x-PE#%x: Slot inactive after reset: 0x%x (attempt %d)\n", pe->phb->global_number, pe->addr, state, i + 1); } /* Resetting the PE may have unfrozen child PEs. If those PEs have been * (potentially) passed through to a guest, re-freeze them: */ if (!include_passed) eeh_pe_refreeze_passed(pe); eeh_pe_state_clear(pe, reset_state, true); return ret; } /** * eeh_save_bars - Save device bars * @edev: PCI device associated EEH device * * Save the values of the device bars. Unlike the restore * routine, this routine is *not* recursive. This is because * PCI devices are added individually; but, for the restore, * an entire slot is reset at a time. */ void eeh_save_bars(struct eeh_dev *edev) { int i; if (!edev) return; for (i = 0; i < 16; i++) eeh_ops->read_config(edev, i * 4, 4, &edev->config_space[i]); /* * For PCI bridges including root port, we need enable bus * master explicitly. Otherwise, it can't fetch IODA table * entries correctly. So we cache the bit in advance so that * we can restore it after reset, either PHB range or PE range. */ if (edev->mode & EEH_DEV_BRIDGE) edev->config_space[1] |= PCI_COMMAND_MASTER; } static int eeh_reboot_notifier(struct notifier_block *nb, unsigned long action, void *unused) { eeh_clear_flag(EEH_ENABLED); return NOTIFY_DONE; } static struct notifier_block eeh_reboot_nb = { .notifier_call = eeh_reboot_notifier, }; static int eeh_device_notifier(struct notifier_block *nb, unsigned long action, void *data) { struct device *dev = data; switch (action) { /* * Note: It's not possible to perform EEH device addition (i.e. * {pseries,pnv}_pcibios_bus_add_device()) here because it depends on * the device's resources, which have not yet been set up. */ case BUS_NOTIFY_DEL_DEVICE: eeh_remove_device(to_pci_dev(dev)); break; default: break; } return NOTIFY_DONE; } static struct notifier_block eeh_device_nb = { .notifier_call = eeh_device_notifier, }; /** * eeh_init - System wide EEH initialization * @ops: struct to trace EEH operation callback functions * * It's the platform's job to call this from an arch_initcall(). */ int eeh_init(struct eeh_ops *ops) { struct pci_controller *hose, *tmp; int ret = 0; /* the platform should only initialise EEH once */ if (WARN_ON(eeh_ops)) return -EEXIST; if (WARN_ON(!ops)) return -ENOENT; eeh_ops = ops; /* Register reboot notifier */ ret = register_reboot_notifier(&eeh_reboot_nb); if (ret) { pr_warn("%s: Failed to register reboot notifier (%d)\n", __func__, ret); return ret; } ret = bus_register_notifier(&pci_bus_type, &eeh_device_nb); if (ret) { pr_warn("%s: Failed to register bus notifier (%d)\n", __func__, ret); return ret; } /* Initialize PHB PEs */ list_for_each_entry_safe(hose, tmp, &hose_list, list_node) eeh_phb_pe_create(hose); eeh_addr_cache_init(); /* Initialize EEH event */ return eeh_event_init(); } /** * eeh_probe_device() - Perform EEH initialization for the indicated pci device * @dev: pci device for which to set up EEH * * This routine must be used to complete EEH initialization for PCI * devices that were added after system boot (e.g. hotplug, dlpar). */ void eeh_probe_device(struct pci_dev *dev) { struct eeh_dev *edev; pr_debug("EEH: Adding device %s\n", pci_name(dev)); /* * pci_dev_to_eeh_dev() can only work if eeh_probe_dev() was * already called for this device. */ if (WARN_ON_ONCE(pci_dev_to_eeh_dev(dev))) { pci_dbg(dev, "Already bound to an eeh_dev!\n"); return; } edev = eeh_ops->probe(dev); if (!edev) { pr_debug("EEH: Adding device failed\n"); return; } /* * FIXME: We rely on pcibios_release_device() to remove the * existing EEH state. The release function is only called if * the pci_dev's refcount drops to zero so if something is * keeping a ref to a device (e.g. a filesystem) we need to * remove the old EEH state. * * FIXME: HEY MA, LOOK AT ME, NO LOCKING! */ if (edev->pdev && edev->pdev != dev) { eeh_pe_tree_remove(edev); eeh_addr_cache_rmv_dev(edev->pdev); eeh_sysfs_remove_device(edev->pdev); /* * We definitely should have the PCI device removed * though it wasn't correctly. So we needn't call * into error handler afterwards. */ edev->mode |= EEH_DEV_NO_HANDLER; } /* bind the pdev and the edev together */ edev->pdev = dev; dev->dev.archdata.edev = edev; eeh_addr_cache_insert_dev(dev); eeh_sysfs_add_device(dev); } /** * eeh_remove_device - Undo EEH setup for the indicated pci device * @dev: pci device to be removed * * This routine should be called when a device is removed from * a running system (e.g. by hotplug or dlpar). It unregisters * the PCI device from the EEH subsystem. I/O errors affecting * this device will no longer be detected after this call; thus, * i/o errors affecting this slot may leave this device unusable. */ void eeh_remove_device(struct pci_dev *dev) { struct eeh_dev *edev; if (!dev || !eeh_enabled()) return; edev = pci_dev_to_eeh_dev(dev); /* Unregister the device with the EEH/PCI address search system */ dev_dbg(&dev->dev, "EEH: Removing device\n"); if (!edev || !edev->pdev || !edev->pe) { dev_dbg(&dev->dev, "EEH: Device not referenced!\n"); return; } /* * During the hotplug for EEH error recovery, we need the EEH * device attached to the parent PE in order for BAR restore * a bit later. So we keep it for BAR restore and remove it * from the parent PE during the BAR resotre. */ edev->pdev = NULL; /* * eeh_sysfs_remove_device() uses pci_dev_to_eeh_dev() so we need to * remove the sysfs files before clearing dev.archdata.edev */ if (edev->mode & EEH_DEV_SYSFS) eeh_sysfs_remove_device(dev); /* * We're removing from the PCI subsystem, that means * the PCI device driver can't support EEH or not * well. So we rely on hotplug completely to do recovery * for the specific PCI device. */ edev->mode |= EEH_DEV_NO_HANDLER; eeh_addr_cache_rmv_dev(dev); /* * The flag "in_error" is used to trace EEH devices for VFs * in error state or not. It's set in eeh_report_error(). If * it's not set, eeh_report_{reset,resume}() won't be called * for the VF EEH device. */ edev->in_error = false; dev->dev.archdata.edev = NULL; if (!(edev->pe->state & EEH_PE_KEEP)) eeh_pe_tree_remove(edev); else edev->mode |= EEH_DEV_DISCONNECTED; } int eeh_unfreeze_pe(struct eeh_pe *pe) { int ret; ret = eeh_pci_enable(pe, EEH_OPT_THAW_MMIO); if (ret) { pr_warn("%s: Failure %d enabling IO on PHB#%x-PE#%x\n", __func__, ret, pe->phb->global_number, pe->addr); return ret; } ret = eeh_pci_enable(pe, EEH_OPT_THAW_DMA); if (ret) { pr_warn("%s: Failure %d enabling DMA on PHB#%x-PE#%x\n", __func__, ret, pe->phb->global_number, pe->addr); return ret; } return ret; } static struct pci_device_id eeh_reset_ids[] = { { PCI_DEVICE(0x19a2, 0x0710) }, /* Emulex, BE */ { PCI_DEVICE(0x10df, 0xe220) }, /* Emulex, Lancer */ { PCI_DEVICE(0x14e4, 0x1657) }, /* Broadcom BCM5719 */ { 0 } }; static int eeh_pe_change_owner(struct eeh_pe *pe) { struct eeh_dev *edev, *tmp; struct pci_dev *pdev; struct pci_device_id *id; int ret; /* Check PE state */ ret = eeh_ops->get_state(pe, NULL); if (ret < 0 || ret == EEH_STATE_NOT_SUPPORT) return 0; /* Unfrozen PE, nothing to do */ if (eeh_state_active(ret)) return 0; /* Frozen PE, check if it needs PE level reset */ eeh_pe_for_each_dev(pe, edev, tmp) { pdev = eeh_dev_to_pci_dev(edev); if (!pdev) continue; for (id = &eeh_reset_ids[0]; id->vendor != 0; id++) { if (id->vendor != PCI_ANY_ID && id->vendor != pdev->vendor) continue; if (id->device != PCI_ANY_ID && id->device != pdev->device) continue; if (id->subvendor != PCI_ANY_ID && id->subvendor != pdev->subsystem_vendor) continue; if (id->subdevice != PCI_ANY_ID && id->subdevice != pdev->subsystem_device) continue; return eeh_pe_reset_and_recover(pe); } } ret = eeh_unfreeze_pe(pe); if (!ret) eeh_pe_state_clear(pe, EEH_PE_ISOLATED, true); return ret; } /** * eeh_dev_open - Increase count of pass through devices for PE * @pdev: PCI device * * Increase count of passed through devices for the indicated * PE. In the result, the EEH errors detected on the PE won't be * reported. The PE owner will be responsible for detection * and recovery. */ int eeh_dev_open(struct pci_dev *pdev) { struct eeh_dev *edev; int ret = -ENODEV; mutex_lock(&eeh_dev_mutex); /* No PCI device ? */ if (!pdev) goto out; /* No EEH device or PE ? */ edev = pci_dev_to_eeh_dev(pdev); if (!edev || !edev->pe) goto out; /* * The PE might have been put into frozen state, but we * didn't detect that yet. The passed through PCI devices * in frozen PE won't work properly. Clear the frozen state * in advance. */ ret = eeh_pe_change_owner(edev->pe); if (ret) goto out; /* Increase PE's pass through count */ atomic_inc(&edev->pe->pass_dev_cnt); mutex_unlock(&eeh_dev_mutex); return 0; out: mutex_unlock(&eeh_dev_mutex); return ret; } EXPORT_SYMBOL_GPL(eeh_dev_open); /** * eeh_dev_release - Decrease count of pass through devices for PE * @pdev: PCI device * * Decrease count of pass through devices for the indicated PE. If * there is no passed through device in PE, the EEH errors detected * on the PE will be reported and handled as usual. */ void eeh_dev_release(struct pci_dev *pdev) { struct eeh_dev *edev; mutex_lock(&eeh_dev_mutex); /* No PCI device ? */ if (!pdev) goto out; /* No EEH device ? */ edev = pci_dev_to_eeh_dev(pdev); if (!edev || !edev->pe || !eeh_pe_passed(edev->pe)) goto out; /* Decrease PE's pass through count */ WARN_ON(atomic_dec_if_positive(&edev->pe->pass_dev_cnt) < 0); eeh_pe_change_owner(edev->pe); out: mutex_unlock(&eeh_dev_mutex); } EXPORT_SYMBOL(eeh_dev_release); #ifdef CONFIG_IOMMU_API /** * eeh_iommu_group_to_pe - Convert IOMMU group to EEH PE * @group: IOMMU group * * The routine is called to convert IOMMU group to EEH PE. */ struct eeh_pe *eeh_iommu_group_to_pe(struct iommu_group *group) { struct pci_dev *pdev = NULL; struct eeh_dev *edev; int ret; /* No IOMMU group ? */ if (!group) return NULL; ret = iommu_group_for_each_dev(group, &pdev, dev_has_iommu_table); if (!ret || !pdev) return NULL; /* No EEH device or PE ? */ edev = pci_dev_to_eeh_dev(pdev); if (!edev || !edev->pe) return NULL; return edev->pe; } EXPORT_SYMBOL_GPL(eeh_iommu_group_to_pe); #endif /* CONFIG_IOMMU_API */ /** * eeh_pe_set_option - Set options for the indicated PE * @pe: EEH PE * @option: requested option * * The routine is called to enable or disable EEH functionality * on the indicated PE, to enable IO or DMA for the frozen PE. */ int eeh_pe_set_option(struct eeh_pe *pe, int option) { int ret = 0; /* Invalid PE ? */ if (!pe) return -ENODEV; /* * EEH functionality could possibly be disabled, just * return error for the case. And the EEH functionality * isn't expected to be disabled on one specific PE. */ switch (option) { case EEH_OPT_ENABLE: if (eeh_enabled()) { ret = eeh_pe_change_owner(pe); break; } ret = -EIO; break; case EEH_OPT_DISABLE: break; case EEH_OPT_THAW_MMIO: case EEH_OPT_THAW_DMA: case EEH_OPT_FREEZE_PE: if (!eeh_ops || !eeh_ops->set_option) { ret = -ENOENT; break; } ret = eeh_pci_enable(pe, option); break; default: pr_debug("%s: Option %d out of range (%d, %d)\n", __func__, option, EEH_OPT_DISABLE, EEH_OPT_THAW_DMA); ret = -EINVAL; } return ret; } EXPORT_SYMBOL_GPL(eeh_pe_set_option); /** * eeh_pe_get_state - Retrieve PE's state * @pe: EEH PE * * Retrieve the PE's state, which includes 3 aspects: enabled * DMA, enabled IO and asserted reset. */ int eeh_pe_get_state(struct eeh_pe *pe) { int result, ret = 0; bool rst_active, dma_en, mmio_en; /* Existing PE ? */ if (!pe) return -ENODEV; if (!eeh_ops || !eeh_ops->get_state) return -ENOENT; /* * If the parent PE is owned by the host kernel and is undergoing * error recovery, we should return the PE state as temporarily * unavailable so that the error recovery on the guest is suspended * until the recovery completes on the host. */ if (pe->parent && !(pe->state & EEH_PE_REMOVED) && (pe->parent->state & (EEH_PE_ISOLATED | EEH_PE_RECOVERING))) return EEH_PE_STATE_UNAVAIL; result = eeh_ops->get_state(pe, NULL); rst_active = !!(result & EEH_STATE_RESET_ACTIVE); dma_en = !!(result & EEH_STATE_DMA_ENABLED); mmio_en = !!(result & EEH_STATE_MMIO_ENABLED); if (rst_active) ret = EEH_PE_STATE_RESET; else if (dma_en && mmio_en) ret = EEH_PE_STATE_NORMAL; else if (!dma_en && !mmio_en) ret = EEH_PE_STATE_STOPPED_IO_DMA; else if (!dma_en && mmio_en) ret = EEH_PE_STATE_STOPPED_DMA; else ret = EEH_PE_STATE_UNAVAIL; return ret; } EXPORT_SYMBOL_GPL(eeh_pe_get_state); static int eeh_pe_reenable_devices(struct eeh_pe *pe, bool include_passed) { struct eeh_dev *edev, *tmp; struct pci_dev *pdev; int ret = 0; eeh_pe_restore_bars(pe); /* * Reenable PCI devices as the devices passed * through are always enabled before the reset. */ eeh_pe_for_each_dev(pe, edev, tmp) { pdev = eeh_dev_to_pci_dev(edev); if (!pdev) continue; ret = pci_reenable_device(pdev); if (ret) { pr_warn("%s: Failure %d reenabling %s\n", __func__, ret, pci_name(pdev)); return ret; } } /* The PE is still in frozen state */ if (include_passed || !eeh_pe_passed(pe)) { ret = eeh_unfreeze_pe(pe); } else pr_info("EEH: Note: Leaving passthrough PHB#%x-PE#%x frozen.\n", pe->phb->global_number, pe->addr); if (!ret) eeh_pe_state_clear(pe, EEH_PE_ISOLATED, include_passed); return ret; } /** * eeh_pe_reset - Issue PE reset according to specified type * @pe: EEH PE * @option: reset type * @include_passed: include passed-through devices? * * The routine is called to reset the specified PE with the * indicated type, either fundamental reset or hot reset. * PE reset is the most important part for error recovery. */ int eeh_pe_reset(struct eeh_pe *pe, int option, bool include_passed) { int ret = 0; /* Invalid PE ? */ if (!pe) return -ENODEV; if (!eeh_ops || !eeh_ops->set_option || !eeh_ops->reset) return -ENOENT; switch (option) { case EEH_RESET_DEACTIVATE: ret = eeh_ops->reset(pe, option); eeh_pe_state_clear(pe, EEH_PE_CFG_BLOCKED, include_passed); if (ret) break; ret = eeh_pe_reenable_devices(pe, include_passed); break; case EEH_RESET_HOT: case EEH_RESET_FUNDAMENTAL: /* * Proactively freeze the PE to drop all MMIO access * during reset, which should be banned as it's always * cause recursive EEH error. */ eeh_ops->set_option(pe, EEH_OPT_FREEZE_PE); eeh_pe_state_mark(pe, EEH_PE_CFG_BLOCKED); ret = eeh_ops->reset(pe, option); break; default: pr_debug("%s: Unsupported option %d\n", __func__, option); ret = -EINVAL; } return ret; } EXPORT_SYMBOL_GPL(eeh_pe_reset); /** * eeh_pe_configure - Configure PCI bridges after PE reset * @pe: EEH PE * * The routine is called to restore the PCI config space for * those PCI devices, especially PCI bridges affected by PE * reset issued previously. */ int eeh_pe_configure(struct eeh_pe *pe) { int ret = 0; /* Invalid PE ? */ if (!pe) return -ENODEV; return ret; } EXPORT_SYMBOL_GPL(eeh_pe_configure); /** * eeh_pe_inject_err - Injecting the specified PCI error to the indicated PE * @pe: the indicated PE * @type: error type * @func: error function * @addr: address * @mask: address mask * * The routine is called to inject the specified PCI error, which * is determined by @type and @func, to the indicated PE for * testing purpose. */ int eeh_pe_inject_err(struct eeh_pe *pe, int type, int func, unsigned long addr, unsigned long mask) { /* Invalid PE ? */ if (!pe) return -ENODEV; /* Unsupported operation ? */ if (!eeh_ops || !eeh_ops->err_inject) return -ENOENT; /* Check on PCI error type */ if (type != EEH_ERR_TYPE_32 && type != EEH_ERR_TYPE_64) return -EINVAL; /* Check on PCI error function */ if (func < EEH_ERR_FUNC_MIN || func > EEH_ERR_FUNC_MAX) return -EINVAL; return eeh_ops->err_inject(pe, type, func, addr, mask); } EXPORT_SYMBOL_GPL(eeh_pe_inject_err); #ifdef CONFIG_PROC_FS static int proc_eeh_show(struct seq_file *m, void *v) { if (!eeh_enabled()) { seq_printf(m, "EEH Subsystem is globally disabled\n"); seq_printf(m, "eeh_total_mmio_ffs=%llu\n", eeh_stats.total_mmio_ffs); } else { seq_printf(m, "EEH Subsystem is enabled\n"); seq_printf(m, "no device=%llu\n" "no device node=%llu\n" "no config address=%llu\n" "check not wanted=%llu\n" "eeh_total_mmio_ffs=%llu\n" "eeh_false_positives=%llu\n" "eeh_slot_resets=%llu\n", eeh_stats.no_device, eeh_stats.no_dn, eeh_stats.no_cfg_addr, eeh_stats.ignored_check, eeh_stats.total_mmio_ffs, eeh_stats.false_positives, eeh_stats.slot_resets); } return 0; } #endif /* CONFIG_PROC_FS */ #ifdef CONFIG_DEBUG_FS static struct pci_dev *eeh_debug_lookup_pdev(struct file *filp, const char __user *user_buf, size_t count, loff_t *ppos) { uint32_t domain, bus, dev, fn; struct pci_dev *pdev; char buf[20]; int ret; memset(buf, 0, sizeof(buf)); ret = simple_write_to_buffer(buf, sizeof(buf)-1, ppos, user_buf, count); if (!ret) return ERR_PTR(-EFAULT); ret = sscanf(buf, "%x:%x:%x.%x", &domain, &bus, &dev, &fn); if (ret != 4) { pr_err("%s: expected 4 args, got %d\n", __func__, ret); return ERR_PTR(-EINVAL); } pdev = pci_get_domain_bus_and_slot(domain, bus, (dev << 3) | fn); if (!pdev) return ERR_PTR(-ENODEV); return pdev; } static int eeh_enable_dbgfs_set(void *data, u64 val) { if (val) eeh_clear_flag(EEH_FORCE_DISABLED); else eeh_add_flag(EEH_FORCE_DISABLED); return 0; } static int eeh_enable_dbgfs_get(void *data, u64 *val) { if (eeh_enabled()) *val = 0x1ul; else *val = 0x0ul; return 0; } DEFINE_DEBUGFS_ATTRIBUTE(eeh_enable_dbgfs_ops, eeh_enable_dbgfs_get, eeh_enable_dbgfs_set, "0x%llx\n"); static ssize_t eeh_force_recover_write(struct file *filp, const char __user *user_buf, size_t count, loff_t *ppos) { struct pci_controller *hose; uint32_t phbid, pe_no; struct eeh_pe *pe; char buf[20]; int ret; ret = simple_write_to_buffer(buf, sizeof(buf), ppos, user_buf, count); if (!ret) return -EFAULT; /* * When PE is NULL the event is a "special" event. Rather than * recovering a specific PE it forces the EEH core to scan for failed * PHBs and recovers each. This needs to be done before any device * recoveries can occur. */ if (!strncmp(buf, "hwcheck", 7)) { __eeh_send_failure_event(NULL); return count; } ret = sscanf(buf, "%x:%x", &phbid, &pe_no); if (ret != 2) return -EINVAL; hose = pci_find_controller_for_domain(phbid); if (!hose) return -ENODEV; /* Retrieve PE */ pe = eeh_pe_get(hose, pe_no); if (!pe) return -ENODEV; /* * We don't do any state checking here since the detection * process is async to the recovery process. The recovery * thread *should* not break even if we schedule a recovery * from an odd state (e.g. PE removed, or recovery of a * non-isolated PE) */ __eeh_send_failure_event(pe); return ret < 0 ? ret : count; } static const struct file_operations eeh_force_recover_fops = { .open = simple_open, .llseek = no_llseek, .write = eeh_force_recover_write, }; static ssize_t eeh_debugfs_dev_usage(struct file *filp, char __user *user_buf, size_t count, loff_t *ppos) { static const char usage[] = "input format: <domain>:<bus>:<dev>.<fn>\n"; return simple_read_from_buffer(user_buf, count, ppos, usage, sizeof(usage) - 1); } static ssize_t eeh_dev_check_write(struct file *filp, const char __user *user_buf, size_t count, loff_t *ppos) { struct pci_dev *pdev; struct eeh_dev *edev; int ret; pdev = eeh_debug_lookup_pdev(filp, user_buf, count, ppos); if (IS_ERR(pdev)) return PTR_ERR(pdev); edev = pci_dev_to_eeh_dev(pdev); if (!edev) { pci_err(pdev, "No eeh_dev for this device!\n"); pci_dev_put(pdev); return -ENODEV; } ret = eeh_dev_check_failure(edev); pci_info(pdev, "eeh_dev_check_failure(%s) = %d\n", pci_name(pdev), ret); pci_dev_put(pdev); return count; } static const struct file_operations eeh_dev_check_fops = { .open = simple_open, .llseek = no_llseek, .write = eeh_dev_check_write, .read = eeh_debugfs_dev_usage, }; static int eeh_debugfs_break_device(struct pci_dev *pdev) { struct resource *bar = NULL; void __iomem *mapped; u16 old, bit; int i, pos; /* Do we have an MMIO BAR to disable? */ for (i = 0; i <= PCI_STD_RESOURCE_END; i++) { struct resource *r = &pdev->resource[i]; if (!r->flags || !r->start) continue; if (r->flags & IORESOURCE_IO) continue; if (r->flags & IORESOURCE_UNSET) continue; bar = r; break; } if (!bar) { pci_err(pdev, "Unable to find Memory BAR to cause EEH with\n"); return -ENXIO; } pci_err(pdev, "Going to break: %pR\n", bar); if (pdev->is_virtfn) { #ifndef CONFIG_PCI_IOV return -ENXIO; #else /* * VFs don't have a per-function COMMAND register, so the best * we can do is clear the Memory Space Enable bit in the PF's * SRIOV control reg. * * Unfortunately, this requires that we have a PF (i.e doesn't * work for a passed-through VF) and it has the potential side * effect of also causing an EEH on every other VF under the * PF. Oh well. */ pdev = pdev->physfn; if (!pdev) return -ENXIO; /* passed through VFs have no PF */ pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_SRIOV); pos += PCI_SRIOV_CTRL; bit = PCI_SRIOV_CTRL_MSE; #endif /* !CONFIG_PCI_IOV */ } else { bit = PCI_COMMAND_MEMORY; pos = PCI_COMMAND; } /* * Process here is: * * 1. Disable Memory space. * * 2. Perform an MMIO to the device. This should result in an error * (CA / UR) being raised by the device which results in an EEH * PE freeze. Using the in_8() accessor skips the eeh detection hook * so the freeze hook so the EEH Detection machinery won't be * triggered here. This is to match the usual behaviour of EEH * where the HW will asynchronously freeze a PE and it's up to * the kernel to notice and deal with it. * * 3. Turn Memory space back on. This is more important for VFs * since recovery will probably fail if we don't. For normal * the COMMAND register is reset as a part of re-initialising * the device. * * Breaking stuff is the point so who cares if it's racy ;) */ pci_read_config_word(pdev, pos, &old); mapped = ioremap(bar->start, PAGE_SIZE); if (!mapped) { pci_err(pdev, "Unable to map MMIO BAR %pR\n", bar); return -ENXIO; } pci_write_config_word(pdev, pos, old & ~bit); in_8(mapped); pci_write_config_word(pdev, pos, old); iounmap(mapped); return 0; } static ssize_t eeh_dev_break_write(struct file *filp, const char __user *user_buf, size_t count, loff_t *ppos) { struct pci_dev *pdev; int ret; pdev = eeh_debug_lookup_pdev(filp, user_buf, count, ppos); if (IS_ERR(pdev)) return PTR_ERR(pdev); ret = eeh_debugfs_break_device(pdev); pci_dev_put(pdev); if (ret < 0) return ret; return count; } static const struct file_operations eeh_dev_break_fops = { .open = simple_open, .llseek = no_llseek, .write = eeh_dev_break_write, .read = eeh_debugfs_dev_usage, }; static ssize_t eeh_dev_can_recover(struct file *filp, const char __user *user_buf, size_t count, loff_t *ppos) { struct pci_driver *drv; struct pci_dev *pdev; size_t ret; pdev = eeh_debug_lookup_pdev(filp, user_buf, count, ppos); if (IS_ERR(pdev)) return PTR_ERR(pdev); /* * In order for error recovery to work the driver needs to implement * .error_detected(), so it can quiesce IO to the device, and * .slot_reset() so it can re-initialise the device after a reset. * * Ideally they'd implement .resume() too, but some drivers which * we need to support (notably IPR) don't so I guess we can tolerate * that. * * .mmio_enabled() is mostly there as a work-around for devices which * take forever to re-init after a hot reset. Implementing that is * strictly optional. */ drv = pci_dev_driver(pdev); if (drv && drv->err_handler && drv->err_handler->error_detected && drv->err_handler->slot_reset) { ret = count; } else { ret = -EOPNOTSUPP; } pci_dev_put(pdev); return ret; } static const struct file_operations eeh_dev_can_recover_fops = { .open = simple_open, .llseek = no_llseek, .write = eeh_dev_can_recover, .read = eeh_debugfs_dev_usage, }; #endif static int __init eeh_init_proc(void) { if (machine_is(pseries) || machine_is(powernv)) { proc_create_single("powerpc/eeh", 0, NULL, proc_eeh_show); #ifdef CONFIG_DEBUG_FS debugfs_create_file_unsafe("eeh_enable", 0600, arch_debugfs_dir, NULL, &eeh_enable_dbgfs_ops); debugfs_create_u32("eeh_max_freezes", 0600, arch_debugfs_dir, &eeh_max_freezes); debugfs_create_bool("eeh_disable_recovery", 0600, arch_debugfs_dir, &eeh_debugfs_no_recover); debugfs_create_file_unsafe("eeh_dev_check", 0600, arch_debugfs_dir, NULL, &eeh_dev_check_fops); debugfs_create_file_unsafe("eeh_dev_break", 0600, arch_debugfs_dir, NULL, &eeh_dev_break_fops); debugfs_create_file_unsafe("eeh_force_recover", 0600, arch_debugfs_dir, NULL, &eeh_force_recover_fops); debugfs_create_file_unsafe("eeh_dev_can_recover", 0600, arch_debugfs_dir, NULL, &eeh_dev_can_recover_fops); eeh_cache_debugfs_init(); #endif } return 0; } __initcall(eeh_init_proc);
Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.
Created with Cregit http://github.com/cregit/cregit
Version 2.0-RC1