[PATCH] powerpc: PCI Error Recovery: PPC64 core recovery routines (77bd7415) · Commits · e / devices / android_kernel_teracube_emerald

arch/powerpc/platforms/pseries/Makefile

+1 −1

Original line number	Diff line number	Diff line
		@@ -4,7 +4,7 @@ obj-$(CONFIG_SMP) += smp.o
		obj-$(CONFIG_IBMVIO) += vio.o
		obj-$(CONFIG_XICS) += xics.o
		obj-$(CONFIG_SCANLOG) += scanlog.o
		obj-$(CONFIG_EEH) += eeh.o eeh_event.o
		obj-$(CONFIG_EEH) += eeh.o eeh_driver.o eeh_event.o

		obj-$(CONFIG_HVC_CONSOLE) += hvconsole.o
		obj-$(CONFIG_HVCS) += hvcserver.o

arch/powerpc/platforms/pseries/eeh.c

+15 −2

Original line number	Diff line number	Diff line
		@@ -485,6 +485,11 @@ static void __eeh_mark_slot (struct device_node *dn, int mode_flag)
		if (PCI_DN(dn)) {
		PCI_DN(dn)->eeh_mode \|= mode_flag;

		/* Mark the pci device driver too */
		struct pci_dev *dev = PCI_DN(dn)->pcidev;
		if (dev && dev->driver)
		dev->error_state = pci_channel_io_frozen;

		if (dn->child)
		__eeh_mark_slot (dn->child, mode_flag);
		}
		@@ -544,6 +549,7 @@ int eeh_dn_check_failure(struct device_node dn, struct pci_dev dev)
		int rets[3];
		unsigned long flags;
		struct pci_dn *pdn;
		enum pci_channel_state state;
		int rc = 0;

		__get_cpu_var(total_mmio_ffs)++;
		@@ -648,7 +654,12 @@ int eeh_dn_check_failure(struct device_node dn, struct pci_dev dev)
		eeh_mark_slot (dn, EEH_MODE_ISOLATED);
		spin_unlock_irqrestore(&confirm_error_lock, flags);

		eeh_send_failure_event (dn, dev, rets[0], rets[2]);
		state = pci_channel_io_normal;
		if ((rets[0] == 2) \|\| (rets[0] == 4))
		state = pci_channel_io_frozen;
		if (rets[0] == 5)
		state = pci_channel_io_perm_failure;
		eeh_send_failure_event (dn, dev, state, rets[2]);

		/* Most EEH events are due to device driver bugs. Having
		* a stack trace will help the device-driver authors figure
		@@ -953,8 +964,10 @@ static void early_enable_eeh(struct device_node dn, void *data)
		* But there are a few cases like display devices that make sense.
		*/
		enable = 1; /* i.e. we will do checking */
		#if 0
		if ((*class_code >> 16) == PCI_BASE_CLASS_DISPLAY)
		enable = 0;
		#endif

		if (!enable)
		pdn->eeh_mode \|= EEH_MODE_NOCHECK;

arch/powerpc/platforms/pseries/eeh_driver.c

0 → 100644

+366 −0

Original line number	Diff line number	Diff line
		/*
		* 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->dev.driver)
		return pdev->dev.driver->name;
		return "";
		}

		/**
		* 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;
		}


		#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 pcierr_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 == PCIERR_RESULT_NONE) res = rc;
		if (*res == PCIERR_RESULT_NEED_RESET) return;
		if (*res == PCIERR_RESULT_DISCONNECT &&
		rc == PCIERR_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 void eeh_reset_device (struct pci_dn pe_dn, struct pci_bus bus)
		{
		if (bus)
		pcibios_remove_pci_devices(bus);

		/* Reset the pci controller. (Asserts RST#; resets config space).
		* Reconfigure bridges and devices */
		rtas_set_slot_reset(pe_dn);

		/* Walk over all functions on this device */
		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);
		}
		}

		/* 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 perm_failure = 0;

		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++;

		if (frozen_pdn->eeh_freeze_count > EEH_MAX_ALLOWED_FREEZES)
		perm_failure = 1;

		/* 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)))
		{
		perm_failure = 1;
		}

		/* Log the error with the rtas logger. */
		if (perm_failure) {
		/*
		* 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",
		pci_name (frozen_pdn->pcidev),
		pcid_name(frozen_pdn->pcidev),
		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, 0);

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

		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,
		pci_name (frozen_pdn->pcidev),
		pcid_name(frozen_pdn->pcidev));

		/* 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.
		*/
		enum pcierr_result result = PCIERR_RESULT_NONE;
		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 == PCIERR_RESULT_NONE) {
		eeh_reset_device(frozen_pdn, frozen_bus);
		}

		/* If any device called out for a reset, then reset the slot */
		if (result == PCIERR_RESULT_NEED_RESET) {
		eeh_reset_device(frozen_pdn, NULL);
		pci_walk_bus(frozen_bus, eeh_report_reset, 0);
		}

		/* If all devices reported they can proceed, the re-enable PIO */
		if (result == PCIERR_RESULT_CAN_RECOVER) {
		/* XXX Not supported; we brute-force reset the device */
		eeh_reset_device(frozen_pdn, NULL);
		pci_walk_bus(frozen_bus, eeh_report_reset, 0);
		}

		/* Tell all device drivers that they can resume operations */
		pci_walk_bus(frozen_bus, eeh_report_resume, 0);
		}

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

arch/powerpc/platforms/pseries/eeh_event.c

+12 −27

Original line number	Diff line number	Diff line
		@@ -21,6 +21,7 @@
		#include <linux/list.h>
		#include <linux/pci.h>
		#include <asm/eeh_event.h>
		#include <asm/ppc-pci.h>

		/** Overview:
		* EEH error states may be detected within exception handlers;
		@@ -36,31 +37,6 @@ LIST_HEAD(eeh_eventlist);
		static void eeh_thread_launcher(void *);
		DECLARE_WORK(eeh_event_wq, eeh_thread_launcher, NULL);

		/**
		* 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)
		{
		/*
		* Since the panic_on_oops sysctl is used to halt the system
		* in light of potential corruption, we can use it here.
		*/
		if (panic_on_oops) {
		panic("EEH: MMIO failure (%d) on device:%s\n", reset_state,
		pci_name(dev));
		}
		else {
		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
		@@ -82,10 +58,16 @@ static int eeh_event_handler(void * dummy)

		spin_lock_irqsave(&eeh_eventlist_lock, flags);
		event = NULL;

		/* Unqueue the event, get ready to process. */
		if (!list_empty(&eeh_eventlist)) {
		event = list_entry(eeh_eventlist.next, struct eeh_event, list);
		list_del(&event->list);
		}

		if (event)
		eeh_mark_slot(event->dn, EEH_MODE_RECOVERING);

		spin_unlock_irqrestore(&eeh_eventlist_lock, flags);
		if (event == NULL)
		break;
		@@ -93,8 +75,11 @@ static int eeh_event_handler(void * dummy)
		printk(KERN_INFO "EEH: Detected PCI bus error on device %s\n",
		pci_name(event->dev));

		eeh_panic (event->dev, event->state);
		handle_eeh_events(event);

		eeh_clear_slot(event->dn, EEH_MODE_RECOVERING);

		pci_dev_put(event->dev);
		kfree(event);
		}

		@@ -122,7 +107,7 @@ static void eeh_thread_launcher(void *dummy)
		*/
		int eeh_send_failure_event (struct device_node *dn,
		struct pci_dev *dev,
		int state,
		enum pci_channel_state state,
		int time_unavail)
		{
		unsigned long flags;

include/asm-powerpc/eeh.h

+5 −3

Original line number	Diff line number	Diff line
		@@ -37,6 +37,8 @@ extern int eeh_subsystem_enabled;
		#define EEH_MODE_SUPPORTED (1<<0)
		#define EEH_MODE_NOCHECK (1<<1)
		#define EEH_MODE_ISOLATED (1<<2)
		#define EEH_MODE_RECOVERING (1<<3)
		#define EEH_MODE_IRQ_DISABLED (1<<4)

		/* Max number of EEH freezes allowed before we consider the device
		* to be permanently disabled. */