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Diffstat (limited to 'arch/ppc64/kernel/eeh.c')
| -rw-r--r-- | arch/ppc64/kernel/eeh.c | 1093 |
1 files changed, 0 insertions, 1093 deletions
diff --git a/arch/ppc64/kernel/eeh.c b/arch/ppc64/kernel/eeh.c deleted file mode 100644 index 9df1d501836..00000000000 --- a/arch/ppc64/kernel/eeh.c +++ /dev/null @@ -1,1093 +0,0 @@ -/* - * eeh.c - * Copyright (C) 2001 Dave Engebretsen & Todd Inglett IBM Corporation - * - * 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. 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA - */ - -#include <linux/init.h> -#include <linux/list.h> -#include <linux/notifier.h> -#include <linux/pci.h> -#include <linux/proc_fs.h> -#include <linux/rbtree.h> -#include <linux/seq_file.h> -#include <linux/spinlock.h> -#include <asm/atomic.h> -#include <asm/eeh.h> -#include <asm/io.h> -#include <asm/machdep.h> -#include <asm/rtas.h> -#include <asm/atomic.h> -#include <asm/systemcfg.h> -#include <asm/ppc-pci.h> - -#undef DEBUG - -/** Overview: - * EEH, or "Extended 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 occured (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. - */ - -/* EEH event workqueue setup. */ -static DEFINE_SPINLOCK(eeh_eventlist_lock); -LIST_HEAD(eeh_eventlist); -static void eeh_event_handler(void *); -DECLARE_WORK(eeh_event_wq, eeh_event_handler, NULL); - -static struct notifier_block *eeh_notifier_chain; - -/* If a device driver keeps reading an MMIO register in an interrupt - * handler after a slot isolation event has occurred, we assume it - * is broken and panic. This sets the threshold for how many read - * attempts we allow before panicking. - */ -#define EEH_MAX_FAILS 100000 - -/* RTAS tokens */ -static int ibm_set_eeh_option; -static int ibm_set_slot_reset; -static int ibm_read_slot_reset_state; -static int ibm_read_slot_reset_state2; -static int ibm_slot_error_detail; - -static int eeh_subsystem_enabled; - -/* Lock to avoid races due to multiple reports of an error */ -static DEFINE_SPINLOCK(confirm_error_lock); - -/* Buffer for reporting slot-error-detail rtas calls */ -static unsigned char slot_errbuf[RTAS_ERROR_LOG_MAX]; -static DEFINE_SPINLOCK(slot_errbuf_lock); -static int eeh_error_buf_size; - -/* System monitoring statistics */ -static DEFINE_PER_CPU(unsigned long, no_device); -static DEFINE_PER_CPU(unsigned long, no_dn); -static DEFINE_PER_CPU(unsigned long, no_cfg_addr); -static DEFINE_PER_CPU(unsigned long, ignored_check); -static DEFINE_PER_CPU(unsigned long, total_mmio_ffs); -static DEFINE_PER_CPU(unsigned long, false_positives); -static DEFINE_PER_CPU(unsigned long, ignored_failures); -static DEFINE_PER_CPU(unsigned long, slot_resets); - -/** - * The pci address cache subsystem. This subsystem places - * PCI device address resources into a red-black tree, sorted - * according to the address range, so that given only an i/o - * address, the corresponding PCI device can be **quickly** - * found. It is safe to perform an address lookup in an interrupt - * context; this ability is an important feature. - * - * Currently, the only customer of this code is the EEH subsystem; - * thus, this code has been somewhat tailored to suit EEH better. - * In particular, the cache does *not* hold the addresses of devices - * for which EEH is not enabled. - * - * (Implementation Note: The RB tree seems to be better/faster - * than any hash algo I could think of for this problem, even - * with the penalty of slow pointer chases for d-cache misses). - */ -struct pci_io_addr_range -{ - struct rb_node rb_node; - unsigned long addr_lo; - unsigned long addr_hi; - struct pci_dev *pcidev; - unsigned int flags; -}; - -static struct pci_io_addr_cache -{ - struct rb_root rb_root; - spinlock_t piar_lock; -} pci_io_addr_cache_root; - -static inline struct pci_dev *__pci_get_device_by_addr(unsigned long addr) -{ - struct rb_node *n = pci_io_addr_cache_root.rb_root.rb_node; - - while (n) { - struct pci_io_addr_range *piar; - piar = rb_entry(n, struct pci_io_addr_range, rb_node); - - if (addr < piar->addr_lo) { - n = n->rb_left; - } else { - if (addr > piar->addr_hi) { - n = n->rb_right; - } else { - pci_dev_get(piar->pcidev); - return piar->pcidev; - } - } - } - - return NULL; -} - -/** - * pci_get_device_by_addr - Get device, given only address - * @addr: mmio (PIO) phys address or i/o port number - * - * Given an mmio phys address, or a port number, find a pci device - * that implements this address. Be sure to pci_dev_put the device - * when finished. I/O port numbers are assumed to be offset - * from zero (that is, they do *not* have pci_io_addr added in). - * It is safe to call this function within an interrupt. - */ -static struct pci_dev *pci_get_device_by_addr(unsigned long addr) -{ - struct pci_dev *dev; - unsigned long flags; - - spin_lock_irqsave(&pci_io_addr_cache_root.piar_lock, flags); - dev = __pci_get_device_by_addr(addr); - spin_unlock_irqrestore(&pci_io_addr_cache_root.piar_lock, flags); - return dev; -} - -#ifdef DEBUG -/* - * Handy-dandy debug print routine, does nothing more - * than print out the contents of our addr cache. - */ -static void pci_addr_cache_print(struct pci_io_addr_cache *cache) -{ - struct rb_node *n; - int cnt = 0; - - n = rb_first(&cache->rb_root); - while (n) { - struct pci_io_addr_range *piar; - piar = rb_entry(n, struct pci_io_addr_range, rb_node); - printk(KERN_DEBUG "PCI: %s addr range %d [%lx-%lx]: %s\n", - (piar->flags & IORESOURCE_IO) ? "i/o" : "mem", cnt, - piar->addr_lo, piar->addr_hi, pci_name(piar->pcidev)); - cnt++; - n = rb_next(n); - } -} -#endif - -/* Insert address range into the rb tree. */ -static struct pci_io_addr_range * -pci_addr_cache_insert(struct pci_dev *dev, unsigned long alo, - unsigned long ahi, unsigned int flags) -{ - struct rb_node **p = &pci_io_addr_cache_root.rb_root.rb_node; - struct rb_node *parent = NULL; - struct pci_io_addr_range *piar; - - /* Walk tree, find a place to insert into tree */ - while (*p) { - parent = *p; - piar = rb_entry(parent, struct pci_io_addr_range, rb_node); - if (ahi < piar->addr_lo) { - p = &parent->rb_left; - } else if (alo > piar->addr_hi) { - p = &parent->rb_right; - } else { - if (dev != piar->pcidev || - alo != piar->addr_lo || ahi != piar->addr_hi) { - printk(KERN_WARNING "PIAR: overlapping address range\n"); - } - return piar; - } - } - piar = (struct pci_io_addr_range *)kmalloc(sizeof(struct pci_io_addr_range), GFP_ATOMIC); - if (!piar) - return NULL; - - piar->addr_lo = alo; - piar->addr_hi = ahi; - piar->pcidev = dev; - piar->flags = flags; - -#ifdef DEBUG - printk(KERN_DEBUG "PIAR: insert range=[%lx:%lx] dev=%s\n", - alo, ahi, pci_name (dev)); -#endif - - rb_link_node(&piar->rb_node, parent, p); - rb_insert_color(&piar->rb_node, &pci_io_addr_cache_root.rb_root); - - return piar; -} - -static void __pci_addr_cache_insert_device(struct pci_dev *dev) -{ - struct device_node *dn; - struct pci_dn *pdn; - int i; - int inserted = 0; - - dn = pci_device_to_OF_node(dev); - if (!dn) { - printk(KERN_WARNING "PCI: no pci dn found for dev=%s\n", pci_name(dev)); - return; - } - - /* Skip any devices for which EEH is not enabled. */ - pdn = PCI_DN(dn); - if (!(pdn->eeh_mode & EEH_MODE_SUPPORTED) || - pdn->eeh_mode & EEH_MODE_NOCHECK) { -#ifdef DEBUG - printk(KERN_INFO "PCI: skip building address cache for=%s - %s\n", - pci_name(dev), pdn->node->full_name); -#endif - return; - } - - /* The cache holds a reference to the device... */ - pci_dev_get(dev); - - /* Walk resources on this device, poke them into the tree */ - for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) { - unsigned long start = pci_resource_start(dev,i); - unsigned long end = pci_resource_end(dev,i); - unsigned int flags = pci_resource_flags(dev,i); - - /* We are interested only bus addresses, not dma or other stuff */ - if (0 == (flags & (IORESOURCE_IO | IORESOURCE_MEM))) - continue; - if (start == 0 || ~start == 0 || end == 0 || ~end == 0) - continue; - pci_addr_cache_insert(dev, start, end, flags); - inserted = 1; - } - - /* If there was nothing to add, the cache has no reference... */ - if (!inserted) - pci_dev_put(dev); -} - -/** - * pci_addr_cache_insert_device - Add a device to the address cache - * @dev: PCI device whose I/O addresses we are interested in. - * - * In order to support the fast lookup of devices based on addresses, - * we maintain a cache of devices that can be quickly searched. - * This routine adds a device to that cache. - */ -static void pci_addr_cache_insert_device(struct pci_dev *dev) -{ - unsigned long flags; - - spin_lock_irqsave(&pci_io_addr_cache_root.piar_lock, flags); - __pci_addr_cache_insert_device(dev); - spin_unlock_irqrestore(&pci_io_addr_cache_root.piar_lock, flags); -} - -static inline void __pci_addr_cache_remove_device(struct pci_dev *dev) -{ - struct rb_node *n; - int removed = 0; - -restart: - n = rb_first(&pci_io_addr_cache_root.rb_root); - while (n) { - struct pci_io_addr_range *piar; - piar = rb_entry(n, struct pci_io_addr_range, rb_node); - - if (piar->pcidev == dev) { - rb_erase(n, &pci_io_addr_cache_root.rb_root); - removed = 1; - kfree(piar); - goto restart; - } - n = rb_next(n); - } - - /* The cache no longer holds its reference to this device... */ - if (removed) - pci_dev_put(dev); -} - -/** - * pci_addr_cache_remove_device - remove pci device from addr cache - * @dev: device to remove - * - * Remove a device from the addr-cache tree. - * This is potentially expensive, since it will walk - * the tree multiple times (once per resource). - * But so what; device removal doesn't need to be that fast. - */ -static void pci_addr_cache_remove_device(struct pci_dev *dev) -{ - unsigned long flags; - - spin_lock_irqsave(&pci_io_addr_cache_root.piar_lock, flags); - __pci_addr_cache_remove_device(dev); - spin_unlock_irqrestore(&pci_io_addr_cache_root.piar_lock, flags); -} - -/** - * pci_addr_cache_build - Build a cache of I/O addresses - * - * Build a cache of pci i/o addresses. This cache will be used to - * find the pci device that corresponds to a given address. - * This routine scans all pci busses to build the cache. - * Must be run late in boot process, after the pci controllers - * have been scaned for devices (after all device resources are known). - */ -void __init pci_addr_cache_build(void) -{ - struct pci_dev *dev = NULL; - - if (!eeh_subsystem_enabled) - return; - - spin_lock_init(&pci_io_addr_cache_root.piar_lock); - - while ((dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev)) != NULL) { - /* Ignore PCI bridges ( XXX why ??) */ - if ((dev->class >> 16) == PCI_BASE_CLASS_BRIDGE) { - continue; - } - pci_addr_cache_insert_device(dev); - } - -#ifdef DEBUG - /* Verify tree built up above, echo back the list of addrs. */ - pci_addr_cache_print(&pci_io_addr_cache_root); -#endif -} - -/* --------------------------------------------------------------- */ -/* Above lies the PCI Address Cache. Below lies the EEH event infrastructure */ - -void eeh_slot_error_detail (struct pci_dn *pdn, int severity) -{ - unsigned long flags; - int rc; - - /* Log the error with the rtas logger */ - spin_lock_irqsave(&slot_errbuf_lock, flags); - memset(slot_errbuf, 0, eeh_error_buf_size); - - rc = rtas_call(ibm_slot_error_detail, - 8, 1, NULL, pdn->eeh_config_addr, - BUID_HI(pdn->phb->buid), - BUID_LO(pdn->phb->buid), NULL, 0, - virt_to_phys(slot_errbuf), - eeh_error_buf_size, - severity); - - if (rc == 0) - log_error(slot_errbuf, ERR_TYPE_RTAS_LOG, 0); - spin_unlock_irqrestore(&slot_errbuf_lock, flags); -} - -/** - * eeh_register_notifier - Register to find out about EEH events. - * @nb: notifier block to callback on events - */ -int eeh_register_notifier(struct notifier_block *nb) -{ - return notifier_chain_register(&eeh_notifier_chain, nb); -} - -/** - * eeh_unregister_notifier - Unregister to an EEH event notifier. - * @nb: notifier block to callback on events - */ -int eeh_unregister_notifier(struct notifier_block *nb) -{ - return notifier_chain_unregister(&eeh_notifier_chain, nb); -} - -/** - * read_slot_reset_state - Read the reset state of a device node's slot - * @dn: device node to read - * @rets: array to return results in - */ -static int read_slot_reset_state(struct pci_dn *pdn, int rets[]) -{ - int token, outputs; - - if (ibm_read_slot_reset_state2 != RTAS_UNKNOWN_SERVICE) { - token = ibm_read_slot_reset_state2; - outputs = 4; - } else { - token = ibm_read_slot_reset_state; - rets[2] = 0; /* fake PE Unavailable info */ - outputs = 3; - } - - return rtas_call(token, 3, outputs, rets, pdn->eeh_config_addr, - BUID_HI(pdn->phb->buid), BUID_LO(pdn->phb->buid)); -} - -/** - * eeh_panic - call panic() for an eeh event that cannot be handled. - * The philosophy of this routine is that it is better to panic and - * halt the OS than it is to risk possible data corruption by - * oblivious device drivers that don't know better. - * - * @dev pci device that had an eeh event - * @reset_state current reset state of the device slot - */ -static void eeh_panic(struct pci_dev *dev, int reset_state) -{ - /* - * XXX We should create a separate sysctl for this. - * - * Since the panic_on_oops sysctl is used to halt the system - * in light of potential corruption, we can use it here. - */ - if (panic_on_oops) { - struct device_node *dn = pci_device_to_OF_node(dev); - eeh_slot_error_detail (PCI_DN(dn), 2 /* Permanent Error */); - panic("EEH: MMIO failure (%d) on device:%s\n", reset_state, - pci_name(dev)); - } - else { - __get_cpu_var(ignored_failures)++; - printk(KERN_INFO "EEH: Ignored MMIO failure (%d) on device:%s\n", - reset_state, pci_name(dev)); - } -} - -/** - * eeh_event_handler - dispatch EEH events. The detection of a frozen - * slot can occur inside an interrupt, where it can be hard to do - * anything about it. The goal of this routine is to pull these - * detection events out of the context of the interrupt handler, and - * re-dispatch them for processing at a later time in a normal context. - * - * @dummy - unused - */ -static void eeh_event_handler(void *dummy) -{ - unsigned long flags; - struct eeh_event *event; - - while (1) { - spin_lock_irqsave(&eeh_eventlist_lock, flags); - event = NULL; - if (!list_empty(&eeh_eventlist)) { - event = list_entry(eeh_eventlist.next, struct eeh_event, list); - list_del(&event->list); - } - spin_unlock_irqrestore(&eeh_eventlist_lock, flags); - if (event == NULL) - break; - - printk(KERN_INFO "EEH: MMIO failure (%d), notifiying device " - "%s\n", event->reset_state, - pci_name(event->dev)); - - notifier_call_chain (&eeh_notifier_chain, - EEH_NOTIFY_FREEZE, event); - - pci_dev_put(event->dev); - kfree(event); - } -} - -/** - * eeh_token_to_phys - convert EEH address token to phys address - * @token i/o token, should be address in the form 0xA.... - */ -static inline unsigned long eeh_token_to_phys(unsigned long token) -{ - pte_t *ptep; - unsigned long pa; - - ptep = find_linux_pte(init_mm.pgd, token); - if (!ptep) - return token; - pa = pte_pfn(*ptep) << PAGE_SHIFT; - - return pa | (token & (PAGE_SIZE-1)); -} - -/** - * Return the "partitionable endpoint" (pe) under which this device lies - */ -static struct device_node * find_device_pe(struct device_node *dn) -{ - while ((dn->parent) && PCI_DN(dn->parent) && - (PCI_DN(dn->parent)->eeh_mode & EEH_MODE_SUPPORTED)) { - dn = dn->parent; - } - return dn; -} - -/** Mark all devices that are peers of this device as failed. - * Mark the device driver too, so that it can see the failure - * immediately; this is critical, since some drivers poll - * status registers in interrupts ... If a driver is polling, - * and the slot is frozen, then the driver can deadlock in - * an interrupt context, which is bad. - */ - -static inline void __eeh_mark_slot (struct device_node *dn) -{ - while (dn) { - PCI_DN(dn)->eeh_mode |= EEH_MODE_ISOLATED; - - if (dn->child) - __eeh_mark_slot (dn->child); - dn = dn->sibling; - } -} - -static inline void __eeh_clear_slot (struct device_node *dn) -{ - while (dn) { - PCI_DN(dn)->eeh_mode &= ~EEH_MODE_ISOLATED; - if (dn->child) - __eeh_clear_slot (dn->child); - dn = dn->sibling; - } -} - -static inline void eeh_clear_slot (struct device_node *dn) -{ - unsigned long flags; - spin_lock_irqsave(&confirm_error_lock, flags); - __eeh_clear_slot (dn); - spin_unlock_irqrestore(&confirm_error_lock, flags); -} - -/** - * eeh_dn_check_failure - check if all 1's data is due to EEH slot freeze - * @dn device node - * @dev pci device, if known - * - * 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_dn_check_failure(struct device_node *dn, struct pci_dev *dev) -{ - int ret; - int rets[3]; - unsigned long flags; - int reset_state; - struct eeh_event *event; - struct pci_dn *pdn; - struct device_node *pe_dn; - int rc = 0; - - __get_cpu_var(total_mmio_ffs)++; - - if (!eeh_subsystem_enabled) - return 0; - - if (!dn) { - __get_cpu_var(no_dn)++; - return 0; - } - pdn = PCI_DN(dn); - - /* Access to IO BARs might get this far and still not want checking. */ - if (!(pdn->eeh_mode & EEH_MODE_SUPPORTED) || - pdn->eeh_mode & EEH_MODE_NOCHECK) { - __get_cpu_var(ignored_check)++; -#ifdef DEBUG - printk ("EEH:ignored check (%x) for %s %s\n", - pdn->eeh_mode, pci_name (dev), dn->full_name); -#endif - return 0; - } - - if (!pdn->eeh_config_addr) { - __get_cpu_var(no_cfg_addr)++; - 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. - */ - spin_lock_irqsave(&confirm_error_lock, flags); - rc = 1; - if (pdn->eeh_mode & EEH_MODE_ISOLATED) { - pdn->eeh_check_count ++; - if (pdn->eeh_check_count >= EEH_MAX_FAILS) { - printk (KERN_ERR "EEH: Device driver ignored %d bad reads, panicing\n", - pdn->eeh_check_count); - dump_stack(); - - /* re-read the slot reset state */ - if (read_slot_reset_state(pdn, rets) != 0) - rets[0] = -1; /* reset state unknown */ - - /* If we are here, then we hit an infinite loop. Stop. */ - panic("EEH: MMIO halt (%d) on device:%s\n", rets[0], pci_name(dev)); - } - 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 = read_slot_reset_state(pdn, rets); - - /* If the call to firmware failed, punt */ - if (ret != 0) { - printk(KERN_WARNING "EEH: read_slot_reset_state() failed; rc=%d dn=%s\n", - ret, dn->full_name); - __get_cpu_var(false_positives)++; - rc = 0; - goto dn_unlock; - } - - /* If EEH is not supported on this device, punt. */ - if (rets[1] != 1) { - printk(KERN_WARNING "EEH: event on unsupported device, rc=%d dn=%s\n", - ret, dn->full_name); - __get_cpu_var(false_positives)++; - rc = 0; - goto dn_unlock; - } - - /* If not the kind of error we know about, punt. */ - if (rets[0] != 2 && rets[0] != 4 && rets[0] != 5) { - __get_cpu_var(false_positives)++; - rc = 0; - goto dn_unlock; - } - - /* Note that config-io to empty slots may fail; - * we recognize empty because they don't have children. */ - if ((rets[0] == 5) && (dn->child == NULL)) { - __get_cpu_var(false_positives)++; - rc = 0; - goto dn_unlock; - } - - __get_cpu_var(slot_resets)++; - - /* Avoid repeated reports of this failure, including problems - * with other functions on this device, and functions under - * bridges. */ - pe_dn = find_device_pe (dn); - __eeh_mark_slot (pe_dn); - spin_unlock_irqrestore(&confirm_error_lock, flags); - - reset_state = rets[0]; - - eeh_slot_error_detail (pdn, 1 /* Temporary Error */); - - printk(KERN_INFO "EEH: MMIO failure (%d) on device: %s %s\n", - rets[0], dn->name, dn->full_name); - event = kmalloc(sizeof(*event), GFP_ATOMIC); - if (event == NULL) { - eeh_panic(dev, reset_state); - return 1; - } - - event->dev = dev; - event->dn = dn; - event->reset_state = reset_state; - - /* We may or may not be called in an interrupt context */ - spin_lock_irqsave(&eeh_eventlist_lock, flags); - list_add(&event->list, &eeh_eventlist); - spin_unlock_irqrestore(&eeh_eventlist_lock, 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. */ - if (rets[0] != 5) dump_stack(); - schedule_work(&eeh_event_wq); - - return 1; - -dn_unlock: - spin_unlock_irqrestore(&confirm_error_lock, flags); - return rc; -} - -EXPORT_SYMBOL_GPL(eeh_dn_check_failure); - -/** - * eeh_check_failure - check if all 1's data is due to EEH slot freeze - * @token i/o token, should be address in the form 0xA.... - * @val value, should be all 1's (XXX why do we need this arg??) - * - * Check for an EEH failure at the given token 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. - */ -unsigned long eeh_check_failure(const volatile void __iomem *token, unsigned long val) -{ - unsigned long addr; - struct pci_dev *dev; - struct device_node *dn; - - /* Finding the phys addr + pci device; this is pretty quick. */ - addr = eeh_token_to_phys((unsigned long __force) token); - dev = pci_get_device_by_addr(addr); - if (!dev) { - __get_cpu_var(no_device)++; - return val; - } - - dn = pci_device_to_OF_node(dev); - eeh_dn_check_failure (dn, dev); - - pci_dev_put(dev); - return val; -} - -EXPORT_SYMBOL(eeh_check_failure); - -struct eeh_early_enable_info { - unsigned int buid_hi; - unsigned int buid_lo; -}; - -/* Enable eeh for the given device node. */ -static void *early_enable_eeh(struct device_node *dn, void *data) -{ - struct eeh_early_enable_info *info = data; - int ret; - char *status = get_property(dn, "status", NULL); - u32 *class_code = (u32 *)get_property(dn, "class-code", NULL); - u32 *vendor_id = (u32 *)get_property(dn, "vendor-id", NULL); - u32 *device_id = (u32 *)get_property(dn, "device-id", NULL); - u32 *regs; - int enable; - struct pci_dn *pdn = PCI_DN(dn); - - pdn->eeh_mode = 0; - pdn->eeh_check_count = 0; - pdn->eeh_freeze_count = 0; - - if (status && strcmp(status, "ok") != 0) - return NULL; /* ignore devices with bad status */ - - /* Ignore bad nodes. */ - if (!class_code || !vendor_id || !device_id) - return NULL; - - /* There is nothing to check on PCI to ISA bridges */ - if (dn->type && !strcmp(dn->type, "isa")) { - pdn->eeh_mode |= EEH_MODE_NOCHECK; - return NULL; - } - - /* - * Now decide if we are going to "Disable" EEH checking - * for this device. We still run with the EEH hardware active, - * but we won't be checking for ff's. This means a driver - * could return bad data (very bad!), an interrupt handler could - * hang waiting on status bits that won't change, etc. - * But there are a few cases like display devices that make sense. - */ - enable = 1; /* i.e. we will do checking */ - if ((*class_code >> 16) == PCI_BASE_CLASS_DISPLAY) - enable = 0; - - if (!enable) - pdn->eeh_mode |= EEH_MODE_NOCHECK; - - /* Ok... see if this device supports EEH. Some do, some don't, - * and the only way to find out is to check each and every one. */ - regs = (u32 *)get_property(dn, "reg", NULL); - if (regs) { - /* First register entry is addr (00BBSS00) */ - /* Try to enable eeh */ - ret = rtas_call(ibm_set_eeh_option, 4, 1, NULL, - regs[0], info->buid_hi, info->buid_lo, - EEH_ENABLE); - if (ret == 0) { - eeh_subsystem_enabled = 1; - pdn->eeh_mode |= EEH_MODE_SUPPORTED; - pdn->eeh_config_addr = regs[0]; -#ifdef DEBUG - printk(KERN_DEBUG "EEH: %s: eeh enabled\n", dn->full_name); -#endif - } else { - - /* This device doesn't support EEH, but it may have an - * EEH parent, in which case we mark it as supported. */ - if (dn->parent && PCI_DN(dn->parent) - && (PCI_DN(dn->parent)->eeh_mode & EEH_MODE_SUPPORTED)) { - /* Parent supports EEH. */ - pdn->eeh_mode |= EEH_MODE_SUPPORTED; - pdn->eeh_config_addr = PCI_DN(dn->parent)->eeh_config_addr; - return NULL; - } - } - } else { - printk(KERN_WARNING "EEH: %s: unable to get reg property.\n", - dn->full_name); - } - - return NULL; -} - -/* - * Initialize EEH by trying to enable it for all of the adapters in the system. - * As a side effect we can determine here if eeh is supported at all. - * Note that we leave EEH on so failed config cycles won't cause a machine - * check. If a user turns off EEH for a particular adapter they are really - * telling Linux to ignore errors. Some hardware (e.g. POWER5) won't - * grant access to a slot if EEH isn't enabled, and so we always enable - * EEH for all slots/all devices. - * - * The eeh-force-off option disables EEH checking globally, for all slots. - * Even if force-off is set, the EEH hardware is still enabled, so that - * newer systems can boot. - */ -void __init eeh_init(void) -{ - struct device_node *phb, *np; - struct eeh_early_enable_info info; - - spin_lock_init(&confirm_error_lock); - spin_lock_init(&slot_errbuf_lock); - - np = of_find_node_by_path("/rtas"); - if (np == NULL) - return; - - ibm_set_eeh_option = rtas_token("ibm,set-eeh-option"); - ibm_set_slot_reset = rtas_token("ibm,set-slot-reset"); - ibm_read_slot_reset_state2 = rtas_token("ibm,read-slot-reset-state2"); - ibm_read_slot_reset_state = rtas_token("ibm,read-slot-reset-state"); - ibm_slot_error_detail = rtas_token("ibm,slot-error-detail"); - - if (ibm_set_eeh_option == RTAS_UNKNOWN_SERVICE) - return; - - eeh_error_buf_size = rtas_token("rtas-error-log-max"); - if (eeh_error_buf_size == RTAS_UNKNOWN_SERVICE) { - eeh_error_buf_size = 1024; - } - if (eeh_error_buf_size > RTAS_ERROR_LOG_MAX) { - printk(KERN_WARNING "EEH: rtas-error-log-max is bigger than allocated " - "buffer ! (%d vs %d)", eeh_error_buf_size, RTAS_ERROR_LOG_MAX); - eeh_error_buf_size = RTAS_ERROR_LOG_MAX; - } - - /* Enable EEH for all adapters. Note that eeh requires buid's */ - for (phb = of_find_node_by_name(NULL, "pci"); phb; - phb = of_find_node_by_name(phb, "pci")) { - unsigned long buid; - - buid = get_phb_buid(phb); - if (buid == 0 || PCI_DN(phb) == NULL) - continue; - - info.buid_lo = BUID_LO(buid); - info.buid_hi = BUID_HI(buid); - traverse_pci_devices(phb, early_enable_eeh, &info); - } - - if (eeh_subsystem_enabled) - printk(KERN_INFO "EEH: PCI Enhanced I/O Error Handling Enabled\n"); - else - printk(KERN_WARNING "EEH: No capable adapters found\n"); -} - -/** - * eeh_add_device_early - enable EEH for the indicated device_node - * @dn: device node for which to set up EEH - * - * This routine must be used to perform EEH initialization for PCI - * devices that were added after system boot (e.g. hotplug, dlpar). - * This routine must be called before any i/o is performed to the - * adapter (inluding any config-space i/o). - * Whether this actually enables EEH or not for this device depends - * on the CEC architecture, type of the device, on earlier boot - * command-line arguments & etc. - */ -void eeh_add_device_early(struct device_node *dn) -{ - struct pci_controller *phb; - struct eeh_early_enable_info info; - - if (!dn || !PCI_DN(dn)) - return; - phb = PCI_DN(dn)->phb; - if (NULL == phb || 0 == phb->buid) { - printk(KERN_WARNING "EEH: Expected buid but found none for %s\n", - dn->full_name); - dump_stack(); - return; - } - - info.buid_hi = BUID_HI(phb->buid); - info.buid_lo = BUID_LO(phb->buid); - early_enable_eeh(dn, &info); -} -EXPORT_SYMBOL_GPL(eeh_add_device_early); - -/** - * eeh_add_device_late - 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_add_device_late(struct pci_dev *dev) -{ - struct device_node *dn; - - if (!dev || !eeh_subsystem_enabled) - return; - -#ifdef DEBUG - printk(KERN_DEBUG "EEH: adding device %s\n", pci_name(dev)); -#endif - - pci_dev_get (dev); - dn = pci_device_to_OF_node(dev); - PCI_DN(dn)->pcidev = dev; - - pci_addr_cache_insert_device (dev); -} -EXPORT_SYMBOL_GPL(eeh_add_device_late); - -/** - * eeh_remove_device - undo EEH setup for the indicated pci device - * @dev: pci device to be removed - * - * This routine should be when a device is removed from a running - * system (e.g. by hotplug or dlpar). - */ -void eeh_remove_device(struct pci_dev *dev) -{ - struct device_node *dn; - if (!dev || !eeh_subsystem_enabled) - return; - - /* Unregister the device with the EEH/PCI address search system */ -#ifdef DEBUG - printk(KERN_DEBUG "EEH: remove device %s\n", pci_name(dev)); -#endif - pci_addr_cache_remove_device(dev); - - dn = pci_device_to_OF_node(dev); - PCI_DN(dn)->pcidev = NULL; - pci_dev_put (dev); -} -EXPORT_SYMBOL_GPL(eeh_remove_device); - -static int proc_eeh_show(struct seq_file *m, void *v) -{ - unsigned int cpu; - unsigned long ffs = 0, positives = 0, failures = 0; - unsigned long resets = 0; - unsigned long no_dev = 0, no_dn = 0, no_cfg = 0, no_check = 0; - - for_each_cpu(cpu) { - ffs += per_cpu(total_mmio_ffs, cpu); - positives += per_cpu(false_positives, cpu); - failures += per_cpu(ignored_failures, cpu); - resets += per_cpu(slot_resets, cpu); - no_dev += per_cpu(no_device, cpu); - no_dn += per_cpu(no_dn, cpu); - no_cfg += per_cpu(no_cfg_addr, cpu); - no_check += per_cpu(ignored_check, cpu); - } - - if (0 == eeh_subsystem_enabled) { - seq_printf(m, "EEH Subsystem is globally disabled\n"); - seq_printf(m, "eeh_total_mmio_ffs=%ld\n", ffs); - } else { - seq_printf(m, "EEH Subsystem is enabled\n"); - seq_printf(m, - "no device=%ld\n" - "no device node=%ld\n" - "no config address=%ld\n" - "check not wanted=%ld\n" - "eeh_total_mmio_ffs=%ld\n" - "eeh_false_positives=%ld\n" - "eeh_ignored_failures=%ld\n" - "eeh_slot_resets=%ld\n", - no_dev, no_dn, no_cfg, no_check, - ffs, positives, failures, resets); - } - - return 0; -} - -static int proc_eeh_open(struct inode *inode, struct file *file) -{ - return single_open(file, proc_eeh_show, NULL); -} - -static struct file_operations proc_eeh_operations = { - .open = proc_eeh_open, - .read = seq_read, - .llseek = seq_lseek, - .release = single_release, -}; - -static int __init eeh_init_proc(void) -{ - struct proc_dir_entry *e; - - if (systemcfg->platform & PLATFORM_PSERIES) { - e = create_proc_entry("ppc64/eeh", 0, NULL); - if (e) - e->proc_fops = &proc_eeh_operations; - } - - return 0; -} -__initcall(eeh_init_proc); |