PCI Error Recovery for PPC64 and misc device drivers

Index: linux-2.6.14-git3/arch/ppc64/kernel/eeh.c
===================================================================
@@ -71,10 +71,6 @@
  *  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 DEFINE_SPINLOCK(eeh_eventlist_lock);
 LIST_HEAD(eeh_eventlist);

Index: linux-2.6.14-git3/include/asm-powerpc/ppc-pci.h
===================================================================
@@ -26,6 +26,10 @@
 
 extern struct pci_dev *ppc64_isabridge_dev;	/* may be NULL if no ISA bus */
 
+/** 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)
+
 /* PCI device_node operations */
 struct device_node;
 typedef void *(*traverse_func)(struct device_node *me, void *data);

134 lines not on this page · raw message

Index: linux-2.6.14-git3/arch/ppc64/kernel/eeh.c
===================================================================
@@ -1,32 +1,31 @@
 /*
  * 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/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/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>

@@ -49,8 +48,8 @@
  *  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.
+ *  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,

@@ -256,18 +255,17 @@
 
 	dn = pci_device_to_OF_node(dev);
 	if (!dn) {
-		printk(KERN_WARNING "PCI: no pci dn found for dev=%s\n",
-			pci_name(dev));
+		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 = dn->data;
+	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\n",
-		       pci_name(dev));
+		printk(KERN_INFO "PCI: skip building address cache for=%s - %s\n",
+		       pci_name(dev), pdn->node->full_name);
 #endif
 		return;
 	}

@@ -410,16 +408,16 @@
  * @dn: device node to read
  * @rets: array to return results in
  */
-static int read_slot_reset_state(struct device_node *dn, int rets[])
+static int read_slot_reset_state(struct pci_dn *pdn, int rets[])
 {
 	int token, outputs;
-	struct pci_dn *pdn = dn->data;
 
 	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;
 	}
 

@@ -496,7 +494,7 @@
 
 /**
  * eeh_token_to_phys - convert EEH address token to phys address
- * @token i/o token, should be address in the form 0xE....
+ * @token i/o token, should be address in the form 0xA....
  */
 static inline unsigned long eeh_token_to_phys(unsigned long token)
 {

@@ -522,7 +520,7 @@
  * 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.
+ * a non-zero value and queues up a slot isolation event notification.
  *
  * It is safe to call this routine in an interrupt context.
  */

@@ -542,7 +540,7 @@
 
 	if (!dn)
 		return 0;
-	pdn = dn->data;
+	pdn = PCI_DN(dn);
 
 	/* Access to IO BARs might get this far and still not want checking. */
 	if (!pdn->eeh_capable || !(pdn->eeh_mode & EEH_MODE_SUPPORTED) ||

@@ -562,7 +560,7 @@
 		atomic_inc(&eeh_fail_count);
 		if (atomic_read(&eeh_fail_count) >= EEH_MAX_FAILS) {
 			/* re-read the slot reset state */
-			if (read_slot_reset_state(dn, rets) != 0)
+			if (read_slot_reset_state(pdn, rets) != 0)
 				rets[0] = -1;	/* reset state unknown */
 			eeh_panic(dev, rets[0]);
 		}

@@ -576,7 +574,7 @@
 	 * function zero of a multi-function device.
 	 * In any case they must share a common PHB.
 	 */
-	ret = read_slot_reset_state(dn, rets);
+	ret = read_slot_reset_state(pdn, rets);
 	if (!(ret == 0 && rets[1] == 1 && (rets[0] == 2 || rets[0] == 4))) {
 		__get_cpu_var(false_positives)++;
 		return 0;

@@ -635,7 +633,6 @@
  * @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.
  * 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

@@ -680,7 +677,7 @@
 	u32 *device_id = (u32 *)get_property(dn, "device-id", NULL);
 	u32 *regs;
 	int enable;
-	struct pci_dn *pdn = dn->data;
+	struct pci_dn *pdn = PCI_DN(dn);
 
 	pdn->eeh_mode = 0;
 

@@ -732,7 +729,7 @@
 
 			/* This device doesn't support EEH, but it may have an
 			 * EEH parent, in which case we mark it as supported. */
-			if (dn->parent && dn->parent->data
+			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;

@@ -745,7 +742,7 @@
 		       dn->full_name);
 	}
 
-	return NULL; 
+	return NULL;
 }
 
 /*

@@ -793,13 +790,11 @@
 	for (phb = of_find_node_by_name(NULL, "pci"); phb;
 	     phb = of_find_node_by_name(phb, "pci")) {
 		unsigned long buid;
-		struct pci_dn *pci;
 
 		buid = get_phb_buid(phb);
-		if (buid == 0 || phb->data == NULL)
+		if (buid == 0 || PCI_DN(phb) == NULL)
 			continue;
 
-		pci = phb->data;
 		info.buid_lo = BUID_LO(buid);
 		info.buid_hi = BUID_HI(buid);
 		traverse_pci_devices(phb, early_enable_eeh, &info);

@@ -828,11 +823,13 @@
 	struct pci_controller *phb;
 	struct eeh_early_enable_info info;
 
-	if (!dn || !dn->data)
+	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\n");
+		printk(KERN_WARNING "EEH: Expected buid but found none for %s\n",
+		       dn->full_name);
+		dump_stack();
 		return;
 	}
 

Index: linux-2.6.14-git3/arch/ppc64/kernel/eeh.c
===================================================================
@@ -219,9 +219,9 @@
 	while (*p) {
 		parent = *p;
 		piar = rb_entry(parent, struct pci_io_addr_range, rb_node);
-		if (alo < piar->addr_lo) {
+		if (ahi < piar->addr_lo) {
 			p = &parent->rb_left;
-		} else if (ahi > piar->addr_hi) {
+		} else if (alo > piar->addr_hi) {
 			p = &parent->rb_right;
 		} else {
 			if (dev != piar->pcidev ||

@@ -240,6 +240,11 @@
 	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);
 

@@ -301,7 +306,7 @@
  * we maintain a cache of devices that can be quickly searched.
  * This routine adds a device to that cache.
  */
-void pci_addr_cache_insert_device(struct pci_dev *dev)
+static void pci_addr_cache_insert_device(struct pci_dev *dev)
 {
 	unsigned long flags;
 

@@ -344,7 +349,7 @@
  * the tree multiple times (once per resource).
  * But so what; device removal doesn't need to be that fast.
  */
-void pci_addr_cache_remove_device(struct pci_dev *dev)
+static void pci_addr_cache_remove_device(struct pci_dev *dev)
 {
 	unsigned long flags;
 

@@ -366,6 +371,9 @@
 {
 	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) {

@@ -837,7 +845,7 @@
 	info.buid_lo = BUID_LO(phb->buid);
 	early_enable_eeh(dn, &info);
 }
-EXPORT_SYMBOL(eeh_add_device_early);
+EXPORT_SYMBOL_GPL(eeh_add_device_early);
 
 /**
  * eeh_add_device_late - perform EEH initialization for the indicated pci device

@@ -848,6 +856,8 @@
  */
 void eeh_add_device_late(struct pci_dev *dev)
 {
+	struct device_node *dn;
+
 	if (!dev || !eeh_subsystem_enabled)
 		return;
 

@@ -855,9 +865,13 @@
 	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(eeh_add_device_late);
+EXPORT_SYMBOL_GPL(eeh_add_device_late);
 
 /**
  * eeh_remove_device - undo EEH setup for the indicated pci device

@@ -868,6 +882,7 @@
  */
 void eeh_remove_device(struct pci_dev *dev)
 {
+	struct device_node *dn;
 	if (!dev || !eeh_subsystem_enabled)
 		return;
 

@@ -876,8 +891,12 @@
 	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(eeh_remove_device);
+EXPORT_SYMBOL_GPL(eeh_remove_device);
 
 static int proc_eeh_show(struct seq_file *m, void *v)
 {

Index: linux-2.6.14-git3/include/asm-powerpc/ppc-pci.h
===================================================================
@@ -39,10 +39,6 @@
 void pci_devs_phb_init(void);
 void pci_devs_phb_init_dynamic(struct pci_controller *phb);
 
-/* PCI address cache management routines */
-void pci_addr_cache_insert_device(struct pci_dev *dev);
-void pci_addr_cache_remove_device(struct pci_dev *dev);
-
 /* From rtas_pci.h */
 void init_pci_config_tokens (void);
 unsigned long get_phb_buid (struct device_node *);

Index: linux-2.6.14-git3/arch/ppc64/kernel/eeh.c
===================================================================
@@ -102,6 +102,10 @@
 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);

@@ -493,8 +497,6 @@
 		notifier_call_chain (&eeh_notifier_chain,
 				     EEH_NOTIFY_FREEZE, event);
 
-		__get_cpu_var(slot_resets)++;
-
 		pci_dev_put(event->dev);
 		kfree(event);
 	}

@@ -546,17 +548,24 @@
 	if (!eeh_subsystem_enabled)
 		return 0;
 
-	if (!dn)
+	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_capable || !(pdn->eeh_mode & EEH_MODE_SUPPORTED) ||
 	    pdn->eeh_mode & EEH_MODE_NOCHECK) {
+		__get_cpu_var(ignored_check)++;
+#ifdef DEBUG
+		printk ("EEH:ignored check for %s %s\n", pci_name (dev), dn->full_name);
+#endif
 		return 0;
 	}
 
 	if (!pdn->eeh_config_addr) {
+		__get_cpu_var(no_cfg_addr)++;
 		return 0;
 	}
 

@@ -590,6 +599,7 @@
 
 	/* prevent repeated reports of this failure */
 	pdn->eeh_mode |= EEH_MODE_ISOLATED;
+	 __get_cpu_var(slot_resets)++;
 
 	reset_state = rets[0];
 

@@ -657,8 +667,10 @@
 	/* 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)
+	if (!dev) {
+		__get_cpu_var(no_device)++;
 		return val;
+	}
 
 	dn = pci_device_to_OF_node(dev);
 	eeh_dn_check_failure (dn, dev);

@@ -903,12 +915,17 @@
 	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) {

@@ -916,13 +933,17 @@
 		seq_printf(m, "eeh_total_mmio_ffs=%ld\n", ffs);
 	} else {
 		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);
+		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;

Index: linux-2.6.14-git3/arch/ppc64/kernel/eeh.c
===================================================================
@@ -397,6 +397,28 @@
 /* --------------------------------------------------------------- */
 /* 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

@@ -454,9 +476,12 @@
 	 * 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)
+	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",

@@ -539,7 +564,7 @@
 	int ret;
 	int rets[3];
 	unsigned long flags;
-	int rc, reset_state;
+	int reset_state;
 	struct eeh_event  *event;
 	struct pci_dn *pdn;
 

@@ -603,20 +628,7 @@
 
 	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, 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,
-	               1 /* Temporary Error */);
-
-	if (rc == 0)
-		log_error(slot_errbuf, ERR_TYPE_RTAS_LOG, 0);
-	spin_unlock_irqrestore(&slot_errbuf_lock, flags);
+	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);

@@ -783,6 +795,8 @@
 	struct device_node *phb, *np;
 	struct eeh_early_enable_info info;
 
+	spin_lock_init(&slot_errbuf_lock);
+
 	np = of_find_node_by_path("/rtas");
 	if (np == NULL)
 		return;

Index: linux-2.6.14-git3/arch/ppc64/kernel/eeh.c
===================================================================
@@ -617,7 +617,32 @@
 	 * In any case they must share a common PHB.
 	 */
 	ret = read_slot_reset_state(pdn, rets);
-	if (!(ret == 0 && rets[1] == 1 && (rets[0] == 2 || rets[0] == 4))) {
+
+	/* 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)++;
+		return 0;
+	}
+
+	/* 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)++;
+		return 0;
+	}
+
+	/* 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)++;
+		return 0;
+	}
+
+	/* 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)++;
 		return 0;
 	}

@@ -650,7 +675,7 @@
 	/* 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();
+	if (rets[0] != 5) dump_stack();
 	schedule_work(&eeh_event_wq);
 
 	return 0;

Index: linux-2.6.14-git3/arch/ppc64/kernel/eeh.c
===================================================================
@@ -96,6 +96,9 @@
 
 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);

@@ -544,6 +547,55 @@
 	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

@@ -567,6 +619,8 @@
 	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)++;
 

@@ -594,10 +648,14 @@
 		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 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) {
 		atomic_inc(&eeh_fail_count);
 		if (atomic_read(&eeh_fail_count) >= EEH_MAX_FAILS) {

@@ -606,7 +664,7 @@
 				rets[0] = -1;	/* reset state unknown */
 			eeh_panic(dev, rets[0]);
 		}
-		return 0;
+		goto dn_unlock;
 	}
 
 	/*

@@ -623,7 +681,8 @@
 		printk(KERN_WARNING "EEH: read_slot_reset_state() failed; rc=%d dn=%s\n",
 		       ret, dn->full_name);
 		__get_cpu_var(false_positives)++;
-		return 0;
+		rc = 0;
+		goto dn_unlock;
 	}
 
 	/* If EEH is not supported on this device, punt. */

@@ -631,25 +690,33 @@
 		printk(KERN_WARNING "EEH: event on unsupported device, rc=%d dn=%s\n",
 		       ret, dn->full_name);
 		__get_cpu_var(false_positives)++;
-		return 0;
+		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)++;
-		return 0;
+		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)++;
-		return 0;
+		rc = 0;
+		goto dn_unlock;
 	}
 
-	/* prevent repeated reports of this failure */
-	pdn->eeh_mode |= EEH_MODE_ISOLATED;
-	 __get_cpu_var(slot_resets)++;
+	__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];
 

@@ -678,10 +745,14 @@
 	if (rets[0] != 5) dump_stack();
 	schedule_work(&eeh_event_wq);
 
-	return 0;
+	return 1;
+
+dn_unlock:
+	spin_unlock_irqrestore(&confirm_error_lock, flags);
+	return rc;
 }
 
-EXPORT_SYMBOL(eeh_dn_check_failure);
+EXPORT_SYMBOL_GPL(eeh_dn_check_failure);
 
 /**
  * eeh_check_failure - check if all 1's data is due to EEH slot freeze

@@ -820,6 +891,7 @@
 	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");

Index: linux-2.6.14-git3/arch/ppc64/kernel/eeh.c
===================================================================
@@ -78,14 +78,12 @@
 
 static struct notifier_block *eeh_notifier_chain;
 
-/*
- * If a device driver keeps reading an MMIO register in an interrupt
+/* 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 EEH_MAX_FAILS	100000
 
 /* RTAS tokens */
 static int ibm_set_eeh_option;

@@ -521,7 +519,6 @@
 		       "%s\n", event->reset_state,
 		       pci_name(event->dev));
 
-		atomic_set(&eeh_fail_count, 0);
 		notifier_call_chain (&eeh_notifier_chain,
 				     EEH_NOTIFY_FREEZE, event);
 

@@ -657,12 +654,18 @@
 	spin_lock_irqsave(&confirm_error_lock, flags);
 	rc = 1;
 	if (pdn->eeh_mode & EEH_MODE_ISOLATED) {
-		atomic_inc(&eeh_fail_count);
-		if (atomic_read(&eeh_fail_count) >= EEH_MAX_FAILS) {
+		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 */
-			eeh_panic(dev, rets[0]);
+
+			/* 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;
 	}

@@ -808,6 +811,8 @@
 	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 */

Index: linux-2.6.14-git3/arch/ppc64/kernel/pci_dn.c
===================================================================
@@ -43,7 +43,7 @@
 	u32 *regs;
 	struct pci_dn *pdn;
 
-	if (phb->is_dynamic)
+	if (mem_init_done)
 		pdn = kmalloc(sizeof(*pdn), GFP_KERNEL);
 	else
 		pdn = alloc_bootmem(sizeof(*pdn));

@@ -120,6 +120,14 @@
 	return NULL;
 }
 
+/** 
+ * pci_devs_phb_init_dynamic - setup pci devices under this PHB
+ * phb: pci-to-host bridge (top-level bridge connecting to cpu)
+ *
+ * This routine is called both during boot, (before the memory
+ * subsystem is set up, before kmalloc is valid) and during the 
+ * dynamic lpar operation of adding a PHB to a running system.
+ */
 void __devinit pci_devs_phb_init_dynamic(struct pci_controller *phb)
 {
 	struct device_node * dn = (struct device_node *) phb->arch_data;

@@ -200,9 +208,14 @@
 	.notifier_call = pci_dn_reconfig_notifier,
 };
 
-/*
- * Actually initialize the phbs.
- * The buswalk on this phb has not happened yet.
+/** 
+ * pci_devs_phb_init - Initialize phbs and pci devs under them.
+ * 
+ * This routine walks over all phb's (pci-host bridges) on the
+ * system, and sets up assorted pci-related structures 
+ * (including pci info in the device node structs) for each
+ * pci device found underneath.  This routine runs once,
+ * early in the boot sequence.
  */
 void __init pci_devs_phb_init(void)
 {

Index: linux-2.6.14-git3/arch/ppc64/kernel/eeh.c
===================================================================
@@ -631,11 +631,12 @@
 	pdn = PCI_DN(dn);
 
 	/* Access to IO BARs might get this far and still not want checking. */
-	if (!pdn->eeh_capable || !(pdn->eeh_mode & EEH_MODE_SUPPORTED) ||
+	if (!(pdn->eeh_mode & EEH_MODE_SUPPORTED) ||
 	    pdn->eeh_mode & EEH_MODE_NOCHECK) {
 		__get_cpu_var(ignored_check)++;
 #ifdef DEBUG
-		printk ("EEH:ignored check for %s %s\n", pci_name (dev), dn->full_name);
+		printk ("EEH:ignored check (%x) for %s %s\n", 
+		        pdn->eeh_mode, pci_name (dev), dn->full_name);
 #endif
 		return 0;
 	}

Index: linux-2.6.14-git3/include/asm-ppc64/pci-bridge.h
===================================================================
@@ -63,7 +63,6 @@
 	int	devfn;			/* for pci devices */
 	int	eeh_mode;		/* See eeh.h for possible EEH_MODEs */
 	int	eeh_config_addr;
-	int	eeh_capable;		/* from firmware */
 	int 	eeh_check_count;	/* # times driver ignored error */
 	int 	eeh_freeze_count;	/* # times this device froze up. */
 	int	eeh_is_bridge;		/* device is pci-to-pci bridge */

Index: linux-2.6.14-git3/arch/ppc64/kernel/eeh.c
===================================================================
@@ -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);

1,093 lines not on this page · raw message

Index: linux-2.6.14-git3/arch/ppc64/kernel/eeh.c
===================================================================
@@ -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);

1,093 lines not on this page · raw message

Index: linux-2.6.14-git3/arch/powerpc/platforms/pseries/eeh.c
===================================================================
@@ -19,7 +19,6 @@
 
 #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>

@@ -27,12 +26,12 @@
 #include <linux/spinlock.h>
 #include <asm/atomic.h>
 #include <asm/eeh.h>
+#include <asm/eeh_event.h>
 #include <asm/io.h>
 #include <asm/machdep.h>
+#include <asm/ppc-pci.h>
 #include <asm/rtas.h>
-#include <asm/atomic.h>
 #include <asm/systemcfg.h>
-#include <asm/ppc-pci.h>
 
 #undef DEBUG
 

@@ -70,14 +69,6 @@
  *  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

@@ -421,24 +412,6 @@
 }
 
 /**
- * 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

@@ -461,73 +434,6 @@
 }
 
 /**
- * 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....
  */

@@ -613,8 +519,6 @@
 	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;

@@ -722,33 +626,12 @@
 	__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);
-
+	eeh_send_failure_event (dn, dev, rets[0], rets[2]);
+	
 	/* 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:

@@ -793,6 +676,14 @@
 
 EXPORT_SYMBOL(eeh_check_failure);
 
+/* ------------------------------------------------------------- */
+/* The code below deals with enabling EEH for devices during  the
+ * early boot sequence.  EEH must be enabled before any PCI probing
+ * can be done.
+ */
+
+#define EEH_ENABLE 1
+
 struct eeh_early_enable_info {
 	unsigned int buid_hi;
 	unsigned int buid_lo;

@@ -850,8 +741,9 @@
 		/* 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);
+		                regs[0], info->buid_hi, info->buid_lo,
+		                EEH_ENABLE);
+
 		if (ret == 0) {
 			eeh_subsystem_enabled = 1;
 			pdn->eeh_mode |= EEH_MODE_SUPPORTED;

52 lines not on this page · raw message

86 lines not on this page · raw message

155 lines not on this page · raw message

Index: linux-2.6.14-git3/include/asm-powerpc/ppc-pci.h
===================================================================
@@ -51,4 +51,18 @@
 extern unsigned long pci_assign_all_buses;
 extern int pci_read_irq_line(struct pci_dev *pci_dev);
 
+/* ---- EEH internal-use-only related routines ---- */
+#ifdef CONFIG_EEH
+/**
+ * rtas_set_slot_reset -- unfreeze a frozen slot
+ *
+ * Clear the EEH-frozen condition on a slot.  This routine
+ * does this by asserting the PCI #RST line for 1/8th of
+ * a second; this routine will sleep while the adapter is
+ * being reset.
+ */
+void rtas_set_slot_reset (struct pci_dn *);
+
+#endif
+
 #endif /* _ASM_POWERPC_PPC_PCI_H */

111 lines not on this page · raw message

Index: linux-2.6.14-git3/arch/powerpc/platforms/pseries/eeh.c
===================================================================
@@ -77,6 +77,9 @@
  */
 #define EEH_MAX_FAILS	100000
 
+/* Misc forward declaraions */
+static void eeh_save_bars(struct pci_dev * pdev, struct pci_dn *pdn);
+
 /* RTAS tokens */
 static int ibm_set_eeh_option;
 static int ibm_set_slot_reset;

@@ -366,6 +369,7 @@
  */
 void __init pci_addr_cache_build(void)
 {
+	struct device_node *dn;
 	struct pci_dev *dev = NULL;
 
 	if (!eeh_subsystem_enabled)

@@ -379,6 +383,10 @@
 			continue;
 		}
 		pci_addr_cache_insert_device(dev);
+
+		/* Save the BAR's; firmware doesn't restore these after EEH reset */
+		dn = pci_device_to_OF_node(dev);
+		eeh_save_bars(dev, PCI_DN(dn));
 	}
 
 #ifdef DEBUG

@@ -775,6 +783,108 @@
 	}
 }
 
+/* ------------------------------------------------------- */
+/** Save and restore of PCI BARs
+ *
+ * Although firmware will set up BARs during boot, it doesn't
+ * set up device BAR's after a device reset, although it will,
+ * if requested, set up bridge configuration. Thus, we need to
+ * configure the PCI devices ourselves.  
+ */
+
+/**
+ * __restore_bars - Restore the Base Address Registers
+ * Loads the PCI configuration space base address registers,
+ * the expansion ROM base address, the latency timer, and etc.
+ * from the saved values in the device node.
+ */
+static inline void __restore_bars (struct pci_dn *pdn)
+{
+	int i;
+
+	if (NULL==pdn->phb) return;
+	for (i=4; i<10; i++) {
+		rtas_write_config(pdn, i*4, 4, pdn->config_space[i]);
+	}
+
+	/* 12 == Expansion ROM Address */
+	rtas_write_config(pdn, 12*4, 4, pdn->config_space[12]);
+
+#define BYTE_SWAP(OFF) (8*((OFF)/4)+3-(OFF))
+#define SAVED_BYTE(OFF) (((u8 *)(pdn->config_space))[BYTE_SWAP(OFF)])
+
+	rtas_write_config (pdn, PCI_CACHE_LINE_SIZE, 1,
+	            SAVED_BYTE(PCI_CACHE_LINE_SIZE));
+
+	rtas_write_config (pdn, PCI_LATENCY_TIMER, 1,
+	            SAVED_BYTE(PCI_LATENCY_TIMER));
+
+	/* max latency, min grant, interrupt pin and line */
+	rtas_write_config(pdn, 15*4, 4, pdn->config_space[15]);
+}
+
+/**
+ * eeh_restore_bars - restore the PCI config space info
+ *
+ * This routine performs a recursive walk to the children
+ * of this device as well.
+ */
+void eeh_restore_bars(struct pci_dn *pdn)
+{
+	struct device_node *dn;
+	if (!pdn) 
+		return;
+	
+	if (! pdn->eeh_is_bridge)
+		__restore_bars (pdn);
+
+	dn = pdn->node->child;
+	while (dn) {
+		eeh_restore_bars (PCI_DN(dn));
+		dn = dn->sibling;
+	}
+}
+
+/**
+ * eeh_save_bars - save device bars
+ *
+ * Save the values of the device bars. Unlike the restore
+ * routine, this routine is *not* recursive. This is because
+ * PCI devices are added individuallly; but, for the restore,
+ * an entire slot is reset at a time.
+ */
+static void eeh_save_bars(struct pci_dev * pdev, struct pci_dn *pdn)
+{
+	int i;
+
+	if (!pdev || !pdn )
+		return;
+	
+	for (i = 0; i < 16; i++)
+		pci_read_config_dword(pdev, i * 4, &pdn->config_space[i]);
+
+	if (pdev->hdr_type == PCI_HEADER_TYPE_BRIDGE)
+		pdn->eeh_is_bridge = 1;
+}
+
+void
+rtas_configure_bridge(struct pci_dn *pdn)
+{
+	int token = rtas_token ("ibm,configure-bridge");
+	int rc;
+
+	if (token == RTAS_UNKNOWN_SERVICE)
+		return;
+	rc = rtas_call(token,3,1, NULL,
+	               pdn->eeh_config_addr,
+	               BUID_HI(pdn->phb->buid),
+	               BUID_LO(pdn->phb->buid));
+	if (rc) {
+		printk (KERN_WARNING "EEH: Unable to configure device bridge (%d) for %s\n",
+		        rc, pdn->node->full_name);
+	}
+}
+
 /* ------------------------------------------------------------- */
 /* The code below deals with enabling EEH for devices during  the
  * early boot sequence.  EEH must be enabled before any PCI probing