arch/powerpc/platforms/pseries/eeh_driver.c - kernel/msm-4.9 - Gitiles

 /*
  * PCI Error Recovery Driver for RPA-compliant PPC64 platform.
  * Copyright (C) 2004, 2005 Linas Vepstas <linas@linas.org>
  *
  * All rights reserved.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation; either version 2 of the License, or (at
  * your option) any later version.
  *
  * This program is distributed in the hope that it will be useful, but
  * WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
  * NON INFRINGEMENT.  See the GNU General Public License for more
  * details.
  *
  * You should have received a copy of the GNU General Public License
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  *
  * Send feedback to <linas@us.ibm.com>
  *
  */
 #include <linux/delay.h>
 #include <linux/irq.h>
 #include <linux/interrupt.h>
 #include <linux/notifier.h>
 #include <linux/pci.h>
 #include <asm/eeh.h>
 #include <asm/eeh_event.h>
 #include <asm/ppc-pci.h>
 #include <asm/pci-bridge.h>
 #include <asm/prom.h>
 #include <asm/rtas.h>


 static inline const char * pcid_name (struct pci_dev *pdev)
 {
 	if (pdev && pdev->dev.driver)
 		return pdev->dev.driver->name;
 	return "";
 }

 #ifdef DEBUG
 static void print_device_node_tree (struct pci_dn *pdn, int dent)
 {
 	int i;
 	if (!pdn) return;
 	for (i=0;i<dent; i++)
 		printk(" ");
 	printk("dn=%s mode=%x \tcfg_addr=%x pe_addr=%x \tfull=%s\n",
 		pdn->node->name, pdn->eeh_mode, pdn->eeh_config_addr,
 		pdn->eeh_pe_config_addr, pdn->node->full_name);
 	dent += 3;
 	struct device_node *pc = pdn->node->child;
 	while (pc) {
 		print_device_node_tree(PCI_DN(pc), dent);
 		pc = pc->sibling;
 	}
 }
 #endif

 /**
  * irq_in_use - return true if this irq is being used
  */
 static int irq_in_use(unsigned int irq)
 {
 	int rc = 0;
 	unsigned long flags;
    struct irq_desc *desc = irq_desc + irq;

 	spin_lock_irqsave(&desc->lock, flags);
 	if (desc->action)
 		rc = 1;
 	spin_unlock_irqrestore(&desc->lock, flags);
 	return rc;
 }

 /* ------------------------------------------------------- */
 /** eeh_report_error - report an EEH error to each device,
  *  collect up and merge the device responses.
  */

 static void eeh_report_error(struct pci_dev *dev, void *userdata)
 {
 	enum pci_ers_result rc, *res = userdata;
 	struct pci_driver *driver = dev->driver;

 	dev->error_state = pci_channel_io_frozen;

 	if (!driver)
 		return;

 	if (irq_in_use (dev->irq)) {
 		struct device_node *dn = pci_device_to_OF_node(dev);
 		PCI_DN(dn)->eeh_mode |= EEH_MODE_IRQ_DISABLED;
 		disable_irq_nosync(dev->irq);
 	}
 	if (!driver->err_handler)
 		return;
 	if (!driver->err_handler->error_detected)
 		return;

 	rc = driver->err_handler->error_detected (dev, pci_channel_io_frozen);
 	if (*res == PCI_ERS_RESULT_NONE) *res = rc;
 	if (*res == PCI_ERS_RESULT_NEED_RESET) return;
 	if (*res == PCI_ERS_RESULT_DISCONNECT &&
 	     rc == PCI_ERS_RESULT_NEED_RESET) *res = rc;
 }

 /** eeh_report_reset -- tell this device that the pci slot
  *  has been reset.
  */

 static void eeh_report_reset(struct pci_dev *dev, void *userdata)
 {
 	struct pci_driver *driver = dev->driver;
 	struct device_node *dn = pci_device_to_OF_node(dev);

 	if (!driver)
 		return;

 	if ((PCI_DN(dn)->eeh_mode) & EEH_MODE_IRQ_DISABLED) {
 		PCI_DN(dn)->eeh_mode &= ~EEH_MODE_IRQ_DISABLED;
 		enable_irq(dev->irq);
 	}
 	if (!driver->err_handler)
 		return;
 	if (!driver->err_handler->slot_reset)
 		return;

 	driver->err_handler->slot_reset(dev);
 }

 static void eeh_report_resume(struct pci_dev *dev, void *userdata)
 {
 	struct pci_driver *driver = dev->driver;

 	dev->error_state = pci_channel_io_normal;

 	if (!driver)
 		return;
 	if (!driver->err_handler)
 		return;
 	if (!driver->err_handler->resume)
 		return;

 	driver->err_handler->resume(dev);
 }

 static void eeh_report_failure(struct pci_dev *dev, void *userdata)
 {
 	struct pci_driver *driver = dev->driver;

 	dev->error_state = pci_channel_io_perm_failure;

 	if (!driver)
 		return;

 	if (irq_in_use (dev->irq)) {
 		struct device_node *dn = pci_device_to_OF_node(dev);
 		PCI_DN(dn)->eeh_mode |= EEH_MODE_IRQ_DISABLED;
 		disable_irq_nosync(dev->irq);
 	}
 	if (!driver->err_handler)
 		return;
 	if (!driver->err_handler->error_detected)
 		return;
 	driver->err_handler->error_detected(dev, pci_channel_io_perm_failure);
 }

 /* ------------------------------------------------------- */
 /**
  * handle_eeh_events -- reset a PCI device after hard lockup.
  *
  * pSeries systems will isolate a PCI slot if the PCI-Host
  * bridge detects address or data parity errors, DMA's
  * occuring to wild addresses (which usually happen due to
  * bugs in device drivers or in PCI adapter firmware).
  * Slot isolations also occur if #SERR, #PERR or other misc
  * PCI-related errors are detected.
  *
  * Recovery process consists of unplugging the device driver
  * (which generated hotplug events to userspace), then issuing
  * a PCI #RST to the device, then reconfiguring the PCI config
  * space for all bridges & devices under this slot, and then
  * finally restarting the device drivers (which cause a second
  * set of hotplug events to go out to userspace).
  */

 /**
  * eeh_reset_device() -- perform actual reset of a pci slot
  * Args: bus: pointer to the pci bus structure corresponding
  *            to the isolated slot. A non-null value will
  *            cause all devices under the bus to be removed
  *            and then re-added.
  *     pe_dn: pointer to a "Partionable Endpoint" device node.
  *            This is the top-level structure on which pci
  *            bus resets can be performed.
  */

 static int eeh_reset_device (struct pci_dn *pe_dn, struct pci_bus *bus)
 {
 	int rc;
 	if (bus)
 		pcibios_remove_pci_devices(bus);

 	/* Reset the pci controller. (Asserts RST#; resets config space).
 	 * Reconfigure bridges and devices. Don't try to bring the system
 	 * up if the reset failed for some reason. */
 	rc = rtas_set_slot_reset(pe_dn);
 	if (rc)
 		return rc;

  	/* New-style config addrs might be shared across multiple devices,
  	 * Walk over all functions on this device */
  	if (pe_dn->eeh_pe_config_addr) {
  		struct device_node *pe = pe_dn->node;
  		pe = pe->parent->child;
  		while (pe) {
  			struct pci_dn *ppe = PCI_DN(pe);
  			if (pe_dn->eeh_pe_config_addr == ppe->eeh_pe_config_addr) {
  				rtas_configure_bridge(ppe);
  				eeh_restore_bars(ppe);
  			}
  			pe = pe->sibling;
  		}
  	} else {
  		rtas_configure_bridge(pe_dn);
  		eeh_restore_bars(pe_dn);
  	}

 	/* Give the system 5 seconds to finish running the user-space
 	 * hotplug shutdown scripts, e.g. ifdown for ethernet.  Yes,
 	 * this is a hack, but if we don't do this, and try to bring
 	 * the device up before the scripts have taken it down,
 	 * potentially weird things happen.
 	 */
 	if (bus) {
 		ssleep (5);
 		pcibios_add_pci_devices(bus);
 	}

 	return 0;
 }

 /* The longest amount of time to wait for a pci device
  * to come back on line, in seconds.
  */
 #define MAX_WAIT_FOR_RECOVERY 15

 void handle_eeh_events (struct eeh_event *event)
 {
 	struct device_node *frozen_dn;
 	struct pci_dn *frozen_pdn;
 	struct pci_bus *frozen_bus;
 	int rc = 0;
 	enum pci_ers_result result = PCI_ERS_RESULT_NONE;
 	const char *pci_str, *drv_str;

 	frozen_dn = find_device_pe(event->dn);
 	frozen_bus = pcibios_find_pci_bus(frozen_dn);

 	if (!frozen_dn) {
 		printk(KERN_ERR "EEH: Error: Cannot find partition endpoint for %s\n",
 		        pci_name(event->dev));
 		return;
 	}

 	/* There are two different styles for coming up with the PE.
 	 * In the old style, it was the highest EEH-capable device
 	 * which was always an EADS pci bridge.  In the new style,
 	 * there might not be any EADS bridges, and even when there are,
 	 * the firmware marks them as "EEH incapable". So another
 	 * two-step is needed to find the pci bus.. */
 	if (!frozen_bus)
 		frozen_bus = pcibios_find_pci_bus (frozen_dn->parent);

 	if (!frozen_bus) {
 		printk(KERN_ERR "EEH: Cannot find PCI bus for %s\n",
 		        frozen_dn->full_name);
 		return;
 	}

 #if 0
 	/* We may get "permanent failure" messages on empty slots.
 	 * These are false alarms. Empty slots have no child dn. */
 	if ((event->state == pci_channel_io_perm_failure) && (frozen_device == NULL))
 		return;
 #endif

 	frozen_pdn = PCI_DN(frozen_dn);
 	frozen_pdn->eeh_freeze_count++;

 	pci_str = pci_name (frozen_pdn->pcidev);
 	drv_str = pcid_name (frozen_pdn->pcidev);
 	if (!pci_str) {
 		pci_str = pci_name (event->dev);
 		drv_str = pcid_name (event->dev);
 	}

 	if (frozen_pdn->eeh_freeze_count > EEH_MAX_ALLOWED_FREEZES)
 		goto hard_fail;

 	/* If the reset state is a '5' and the time to reset is 0 (infinity)
 	 * or is more then 15 seconds, then mark this as a permanent failure.
 	 */
 	if ((event->state == pci_channel_io_perm_failure) &&
 	    ((event->time_unavail <= 0) ||
 	     (event->time_unavail > MAX_WAIT_FOR_RECOVERY*1000)))
 		goto hard_fail;

 	eeh_slot_error_detail(frozen_pdn, 1 /* Temporary Error */);
 	printk(KERN_WARNING
 	   "EEH: This PCI device has failed %d times since last reboot: %s - %s\n",
 		frozen_pdn->eeh_freeze_count, drv_str, pci_str);

 	/* Walk the various device drivers attached to this slot through
 	 * a reset sequence, giving each an opportunity to do what it needs
 	 * to accomplish the reset.  Each child gets a report of the
 	 * status ... if any child can't handle the reset, then the entire
 	 * slot is dlpar removed and added.
 	 */
 	pci_walk_bus(frozen_bus, eeh_report_error, &result);

 	/* If all device drivers were EEH-unaware, then shut
 	 * down all of the device drivers, and hope they
 	 * go down willingly, without panicing the system.
 	 */
 	if (result == PCI_ERS_RESULT_NONE) {
 		rc = eeh_reset_device(frozen_pdn, frozen_bus);
 		if (rc)
 			goto hard_fail;
 	}

 	/* If any device called out for a reset, then reset the slot */
 	if (result == PCI_ERS_RESULT_NEED_RESET) {
 		rc = eeh_reset_device(frozen_pdn, NULL);
 		if (rc)
 			goto hard_fail;
 		pci_walk_bus(frozen_bus, eeh_report_reset, NULL);
 	}

 	/* If all devices reported they can proceed, the re-enable PIO */
 	if (result == PCI_ERS_RESULT_CAN_RECOVER) {
 		/* XXX Not supported; we brute-force reset the device */
 		rc = eeh_reset_device(frozen_pdn, NULL);
 		if (rc)
 			goto hard_fail;
 		pci_walk_bus(frozen_bus, eeh_report_reset, NULL);
 	}

 	/* Tell all device drivers that they can resume operations */
 	pci_walk_bus(frozen_bus, eeh_report_resume, NULL);

 	return;

 hard_fail:
 	/*
 	 * About 90% of all real-life EEH failures in the field
 	 * are due to poorly seated PCI cards. Only 10% or so are
 	 * due to actual, failed cards.
 	 */
 	printk(KERN_ERR
 	   "EEH: PCI device %s - %s has failed %d times \n"
 	   "and has been permanently disabled.  Please try reseating\n"
 	   "this device or replacing it.\n",
 		drv_str, pci_str, frozen_pdn->eeh_freeze_count);

 	eeh_slot_error_detail(frozen_pdn, 2 /* Permanent Error */);

 	/* Notify all devices that they're about to go down. */
 	pci_walk_bus(frozen_bus, eeh_report_failure, NULL);

 	/* Shut down the device drivers for good. */
 	pcibios_remove_pci_devices(frozen_bus);
 }

 /* ---------- end of file ---------- */
	/*
	* PCI Error Recovery Driver for RPA-compliant PPC64 platform.
	* Copyright (C) 2004, 2005 Linas Vepstas <linas@linas.org>
	*
	* All rights reserved.
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License as published by
	* the Free Software Foundation; either version 2 of the License, or (at
	* your option) any later version.
	*
	* This program is distributed in the hope that it will be useful, but
	* WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
	* NON INFRINGEMENT. See the GNU General Public License for more
	* details.
	*
	* You should have received a copy of the GNU General Public License
	* along with this program; if not, write to the Free Software
	* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
	*
	* Send feedback to <linas@us.ibm.com>
	*
	*/
	#include <linux/delay.h>
	#include <linux/irq.h>
	#include <linux/interrupt.h>
	#include <linux/notifier.h>
	#include <linux/pci.h>
	#include <asm/eeh.h>
	#include <asm/eeh_event.h>
	#include <asm/ppc-pci.h>
	#include <asm/pci-bridge.h>
	#include <asm/prom.h>
	#include <asm/rtas.h>


	static inline const char * pcid_name (struct pci_dev *pdev)
	{
	if (pdev && pdev->dev.driver)
	return pdev->dev.driver->name;
	return "";
	}

	#ifdef DEBUG
	static void print_device_node_tree (struct pci_dn *pdn, int dent)
	{
	int i;
	if (!pdn) return;
	for (i=0;i<dent; i++)
	printk(" ");
	printk("dn=%s mode=%x \tcfg_addr=%x pe_addr=%x \tfull=%s\n",
	pdn->node->name, pdn->eeh_mode, pdn->eeh_config_addr,
	pdn->eeh_pe_config_addr, pdn->node->full_name);
	dent += 3;
	struct device_node *pc = pdn->node->child;
	while (pc) {
	print_device_node_tree(PCI_DN(pc), dent);
	pc = pc->sibling;
	}
	}
	#endif

	/**
	* irq_in_use - return true if this irq is being used
	*/
	static int irq_in_use(unsigned int irq)
	{
	int rc = 0;
	unsigned long flags;
	struct irq_desc *desc = irq_desc + irq;

	spin_lock_irqsave(&desc->lock, flags);
	if (desc->action)
	rc = 1;
	spin_unlock_irqrestore(&desc->lock, flags);
	return rc;
	}

	/* ------------------------------------------------------- */
	/** eeh_report_error - report an EEH error to each device,
	* collect up and merge the device responses.
	*/

	static void eeh_report_error(struct pci_dev dev, void userdata)
	{
	enum pci_ers_result rc, *res = userdata;
	struct pci_driver *driver = dev->driver;

	dev->error_state = pci_channel_io_frozen;

	if (!driver)
	return;

	if (irq_in_use (dev->irq)) {
	struct device_node *dn = pci_device_to_OF_node(dev);
	PCI_DN(dn)->eeh_mode \|= EEH_MODE_IRQ_DISABLED;
	disable_irq_nosync(dev->irq);
	}
	if (!driver->err_handler)
	return;
	if (!driver->err_handler->error_detected)
	return;

	rc = driver->err_handler->error_detected (dev, pci_channel_io_frozen);
	if (res == PCI_ERS_RESULT_NONE) res = rc;
	if (*res == PCI_ERS_RESULT_NEED_RESET) return;
	if (*res == PCI_ERS_RESULT_DISCONNECT &&
	rc == PCI_ERS_RESULT_NEED_RESET) *res = rc;
	}

	/** eeh_report_reset -- tell this device that the pci slot
	* has been reset.
	*/

	static void eeh_report_reset(struct pci_dev dev, void userdata)
	{
	struct pci_driver *driver = dev->driver;
	struct device_node *dn = pci_device_to_OF_node(dev);

	if (!driver)
	return;

	if ((PCI_DN(dn)->eeh_mode) & EEH_MODE_IRQ_DISABLED) {
	PCI_DN(dn)->eeh_mode &= ~EEH_MODE_IRQ_DISABLED;
	enable_irq(dev->irq);
	}
	if (!driver->err_handler)
	return;
	if (!driver->err_handler->slot_reset)
	return;

	driver->err_handler->slot_reset(dev);
	}

	static void eeh_report_resume(struct pci_dev dev, void userdata)
	{
	struct pci_driver *driver = dev->driver;

	dev->error_state = pci_channel_io_normal;

	if (!driver)
	return;
	if (!driver->err_handler)
	return;
	if (!driver->err_handler->resume)
	return;

	driver->err_handler->resume(dev);
	}

	static void eeh_report_failure(struct pci_dev dev, void userdata)
	{
	struct pci_driver *driver = dev->driver;

	dev->error_state = pci_channel_io_perm_failure;

	if (!driver)
	return;

	if (irq_in_use (dev->irq)) {
	struct device_node *dn = pci_device_to_OF_node(dev);
	PCI_DN(dn)->eeh_mode \|= EEH_MODE_IRQ_DISABLED;
	disable_irq_nosync(dev->irq);
	}
	if (!driver->err_handler)
	return;
	if (!driver->err_handler->error_detected)
	return;
	driver->err_handler->error_detected(dev, pci_channel_io_perm_failure);
	}

	/* ------------------------------------------------------- */
	/**
	* handle_eeh_events -- reset a PCI device after hard lockup.
	*
	* pSeries systems will isolate a PCI slot if the PCI-Host
	* bridge detects address or data parity errors, DMA's
	* occuring to wild addresses (which usually happen due to
	* bugs in device drivers or in PCI adapter firmware).
	* Slot isolations also occur if #SERR, #PERR or other misc
	* PCI-related errors are detected.
	*
	* Recovery process consists of unplugging the device driver
	* (which generated hotplug events to userspace), then issuing
	* a PCI #RST to the device, then reconfiguring the PCI config
	* space for all bridges & devices under this slot, and then
	* finally restarting the device drivers (which cause a second
	* set of hotplug events to go out to userspace).
	*/

	/**
	* eeh_reset_device() -- perform actual reset of a pci slot
	* Args: bus: pointer to the pci bus structure corresponding
	* to the isolated slot. A non-null value will
	* cause all devices under the bus to be removed
	* and then re-added.
	* pe_dn: pointer to a "Partionable Endpoint" device node.
	* This is the top-level structure on which pci
	* bus resets can be performed.
	*/

	static int eeh_reset_device (struct pci_dn pe_dn, struct pci_bus bus)
	{
	int rc;
	if (bus)
	pcibios_remove_pci_devices(bus);

	/* Reset the pci controller. (Asserts RST#; resets config space).
	* Reconfigure bridges and devices. Don't try to bring the system
	* up if the reset failed for some reason. */
	rc = rtas_set_slot_reset(pe_dn);
	if (rc)
	return rc;

	/* New-style config addrs might be shared across multiple devices,
	* Walk over all functions on this device */
	if (pe_dn->eeh_pe_config_addr) {
	struct device_node *pe = pe_dn->node;
	pe = pe->parent->child;
	while (pe) {
	struct pci_dn *ppe = PCI_DN(pe);
	if (pe_dn->eeh_pe_config_addr == ppe->eeh_pe_config_addr) {
	rtas_configure_bridge(ppe);
	eeh_restore_bars(ppe);
	}
	pe = pe->sibling;
	}
	} else {
	rtas_configure_bridge(pe_dn);
	eeh_restore_bars(pe_dn);
	}

	/* Give the system 5 seconds to finish running the user-space
	* hotplug shutdown scripts, e.g. ifdown for ethernet. Yes,
	* this is a hack, but if we don't do this, and try to bring
	* the device up before the scripts have taken it down,
	* potentially weird things happen.
	*/
	if (bus) {
	ssleep (5);
	pcibios_add_pci_devices(bus);
	}

	return 0;
	}

	/* The longest amount of time to wait for a pci device
	* to come back on line, in seconds.
	*/
	#define MAX_WAIT_FOR_RECOVERY 15

	void handle_eeh_events (struct eeh_event *event)
	{
	struct device_node *frozen_dn;
	struct pci_dn *frozen_pdn;
	struct pci_bus *frozen_bus;
	int rc = 0;
	enum pci_ers_result result = PCI_ERS_RESULT_NONE;
	const char pci_str, drv_str;

	frozen_dn = find_device_pe(event->dn);
	frozen_bus = pcibios_find_pci_bus(frozen_dn);

	if (!frozen_dn) {
	printk(KERN_ERR "EEH: Error: Cannot find partition endpoint for %s\n",
	pci_name(event->dev));
	return;
	}

	/* There are two different styles for coming up with the PE.
	* In the old style, it was the highest EEH-capable device
	* which was always an EADS pci bridge. In the new style,
	* there might not be any EADS bridges, and even when there are,
	* the firmware marks them as "EEH incapable". So another
	* two-step is needed to find the pci bus.. */
	if (!frozen_bus)
	frozen_bus = pcibios_find_pci_bus (frozen_dn->parent);

	if (!frozen_bus) {
	printk(KERN_ERR "EEH: Cannot find PCI bus for %s\n",
	frozen_dn->full_name);
	return;
	}

	#if 0
	/* We may get "permanent failure" messages on empty slots.
	* These are false alarms. Empty slots have no child dn. */
	if ((event->state == pci_channel_io_perm_failure) && (frozen_device == NULL))
	return;
	#endif

	frozen_pdn = PCI_DN(frozen_dn);
	frozen_pdn->eeh_freeze_count++;

	pci_str = pci_name (frozen_pdn->pcidev);
	drv_str = pcid_name (frozen_pdn->pcidev);
	if (!pci_str) {
	pci_str = pci_name (event->dev);
	drv_str = pcid_name (event->dev);
	}

	if (frozen_pdn->eeh_freeze_count > EEH_MAX_ALLOWED_FREEZES)
	goto hard_fail;

	/* If the reset state is a '5' and the time to reset is 0 (infinity)
	* or is more then 15 seconds, then mark this as a permanent failure.
	*/
	if ((event->state == pci_channel_io_perm_failure) &&
	((event->time_unavail <= 0) \|\|
	(event->time_unavail > MAX_WAIT_FOR_RECOVERY*1000)))
	goto hard_fail;

	eeh_slot_error_detail(frozen_pdn, 1 /* Temporary Error */);
	printk(KERN_WARNING
	"EEH: This PCI device has failed %d times since last reboot: %s - %s\n",
	frozen_pdn->eeh_freeze_count, drv_str, pci_str);

	/* Walk the various device drivers attached to this slot through
	* a reset sequence, giving each an opportunity to do what it needs
	* to accomplish the reset. Each child gets a report of the
	* status ... if any child can't handle the reset, then the entire
	* slot is dlpar removed and added.
	*/
	pci_walk_bus(frozen_bus, eeh_report_error, &result);

	/* If all device drivers were EEH-unaware, then shut
	* down all of the device drivers, and hope they
	* go down willingly, without panicing the system.
	*/
	if (result == PCI_ERS_RESULT_NONE) {
	rc = eeh_reset_device(frozen_pdn, frozen_bus);
	if (rc)
	goto hard_fail;
	}

	/* If any device called out for a reset, then reset the slot */
	if (result == PCI_ERS_RESULT_NEED_RESET) {
	rc = eeh_reset_device(frozen_pdn, NULL);
	if (rc)
	goto hard_fail;
	pci_walk_bus(frozen_bus, eeh_report_reset, NULL);
	}

	/* If all devices reported they can proceed, the re-enable PIO */
	if (result == PCI_ERS_RESULT_CAN_RECOVER) {
	/* XXX Not supported; we brute-force reset the device */
	rc = eeh_reset_device(frozen_pdn, NULL);
	if (rc)
	goto hard_fail;
	pci_walk_bus(frozen_bus, eeh_report_reset, NULL);
	}

	/* Tell all device drivers that they can resume operations */
	pci_walk_bus(frozen_bus, eeh_report_resume, NULL);

	return;

	hard_fail:
	/*
	* About 90% of all real-life EEH failures in the field
	* are due to poorly seated PCI cards. Only 10% or so are
	* due to actual, failed cards.
	*/
	printk(KERN_ERR
	"EEH: PCI device %s - %s has failed %d times \n"
	"and has been permanently disabled. Please try reseating\n"
	"this device or replacing it.\n",
	drv_str, pci_str, frozen_pdn->eeh_freeze_count);

	eeh_slot_error_detail(frozen_pdn, 2 /* Permanent Error */);

	/* Notify all devices that they're about to go down. */
	pci_walk_bus(frozen_bus, eeh_report_failure, NULL);

	/* Shut down the device drivers for good. */
	pcibios_remove_pci_devices(frozen_bus);
	}

	/* ---------- end of file ---------- */