* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
-#include <linux/bootmem.h>
#include <linux/init.h>
-#include <linux/list.h>
-#include <linux/mm.h>
-#include <linux/notifier.h>
#include <linux/pci.h>
#include <linux/proc_fs.h>
+#include <linux/bootmem.h>
+#include <linux/mm.h>
#include <linux/rbtree.h>
-#include <linux/seq_file.h>
#include <linux/spinlock.h>
-#include <asm/eeh.h>
+#include <linux/seq_file.h>
+#include <asm/paca.h>
+#include <asm/processor.h>
+#include <asm/naca.h>
#include <asm/io.h>
#include <asm/machdep.h>
+#include <asm/pgtable.h>
#include <asm/rtas.h>
-#include <asm/atomic.h>
#include "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 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.
- */
-
-/** Bus Unit ID macros; get low and hi 32-bits of the 64-bit BUID */
#define BUID_HI(buid) ((buid) >> 32)
#define BUID_LO(buid) ((buid) & 0xffffffff)
-
-/* EEH event workqueue setup. */
-static spinlock_t eeh_eventlist_lock = SPIN_LOCK_UNLOCKED;
-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 1000
-static atomic_t eeh_fail_count;
+#define CONFIG_ADDR(busno, devfn) \
+ (((((busno) & 0xff) << 8) | ((devfn) & 0xf8)) << 8)
/* RTAS tokens */
static int ibm_set_eeh_option;
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.
+ * found.
*
* Currently, the only customer of this code is the EEH subsystem;
* thus, this code has been somewhat tailored to suit EEH better.
#endif
}
-/* --------------------------------------------------------------- */
-/* Above lies the PCI Address Cache. Below lies the EEH event infrastructure */
-
-/**
- * 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);
-}
-
-/**
- * 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)
- panic("EEH: MMIO failure (%d) on device:%s %s\n", reset_state,
- pci_name(dev), pci_pretty_name(dev));
- else {
- __get_cpu_var(ignored_failures)++;
- printk(KERN_INFO "EEH: Ignored MMIO failure (%d) on device:%s %s\n",
- reset_state, pci_name(dev), pci_pretty_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 %s\n", event->reset_state,
- pci_name(event->dev), pci_pretty_name(event->dev));
-
- atomic_set(&eeh_fail_count, 0);
- notifier_call_chain (&eeh_notifier_chain,
- EEH_NOTIFY_FREEZE, event);
-
- __get_cpu_var(slot_resets)++;
-
- 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 0xE....
*
* 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
+ * find out if this is due to an EEH slot freeze event. 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 solt isolation event notification.
+ * an error code.
*
* It is safe to call this routine in an interrupt context.
*/
int ret;
int rets[3];
unsigned long flags;
- int rc, reset_state;
- struct eeh_event *event;
__get_cpu_var(total_mmio_ffs)++;
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...
- */
- if (dn->eeh_mode & EEH_MODE_ISOLATED) {
- atomic_inc(&eeh_fail_count);
- if (atomic_read(&eeh_fail_count) >= EEH_MAX_FAILS) {
- /* re-read the slot reset state */
- rets[0] = -1;
- rtas_call(ibm_read_slot_reset_state, 3, 3, rets,
- dn->eeh_config_addr,
- BUID_HI(dn->phb->buid),
- BUID_LO(dn->phb->buid));
- eeh_panic(dev, rets[0]);
- }
- return 0;
- }
-
/*
* Now test for an EEH failure. This is VERY expensive.
* Note that the eeh_config_addr may be a parent device
*/
ret = read_slot_reset_state(dn, rets);
- if (!(ret == 0 && rets[1] == 1 && (rets[0] == 2 || rets[0] == 4))) {
+ if (ret == 0 && rets[1] == 1 && (rets[0] == 2 || rets[0] == 4)) {
+ int log_event;
+
+ spin_lock_irqsave(&slot_errbuf_lock, flags);
+ memset(slot_errbuf, 0, eeh_error_buf_size);
+
+ log_event = rtas_call(ibm_slot_error_detail,
+ 8, 1, NULL, dn->eeh_config_addr,
+ BUID_HI(dn->phb->buid),
+ BUID_LO(dn->phb->buid), NULL, 0,
+ virt_to_phys(slot_errbuf),
+ eeh_error_buf_size,
+ 1 /* Temporary Error */);
+
+ if (log_event == 0)
+ log_error(slot_errbuf, ERR_TYPE_RTAS_LOG,
+ 1 /* Fatal */);
+
+ spin_unlock_irqrestore(&slot_errbuf_lock, flags);
+
+ printk(KERN_INFO "EEH: MMIO failure (%d) on device: %s %s\n",
+ rets[0], dn->name, dn->full_name);
+ WARN_ON(1);
+
+ /*
+ * 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) {
+ panic("EEH: MMIO failure (%d) on device: %s %s\n",
+ rets[0], dn->name, dn->full_name);
+ } else {
+ __get_cpu_var(ignored_failures)++;
+ }
+ } else {
__get_cpu_var(false_positives)++;
- return 0;
}
- /* prevent repeated reports of this failure */
- dn->eeh_mode |= EEH_MODE_ISOLATED;
-
- reset_state = rets[0];
-
- 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, dn->eeh_config_addr,
- BUID_HI(dn->phb->buid),
- BUID_LO(dn->phb->buid), NULL, 0,
- virt_to_phys(slot_errbuf),
- eeh_error_buf_size,
- 1 /* Temporary Error */);
-
- if (rc == 0)
- log_error(slot_errbuf, ERR_TYPE_RTAS_LOG, 0);
- spin_unlock_irqrestore(&slot_errbuf_lock, flags);
-
- 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. */
- dump_stack();
- schedule_work(&eeh_event_wq);
-
return 0;
}
{
unsigned int cpu;
unsigned long ffs = 0, positives = 0, failures = 0;
- unsigned long resets = 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);
}
if (0 == eeh_subsystem_enabled) {
seq_printf(m, "EEH Subsystem is enabled\n");
seq_printf(m, "eeh_total_mmio_ffs=%ld\n"
"eeh_false_positives=%ld\n"
- "eeh_ignored_failures=%ld\n"
- "eeh_slot_resets=%ld\n"
- "eeh_fail_count=%d\n",
- ffs, positives, failures, resets,
- eeh_fail_count.counter);
+ "eeh_ignored_failures=%ld\n",
+ ffs, positives, failures);
}
return 0;
git://git.onelab.eu / linux-2.6.git / blobdiff