powerpc/eeh: Handle EEH error based on PE

The patch reworks the current implementation so that the eeh errors
will be handled basing on PE instead of eeh device.

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

5 files changed, 125 insertions, 137 deletions

diff --git a/arch/powerpc/include/asm/eeh.h b/arch/powerpc/include/asm/eeh.h
index 629fb27c093e..d25a693595f8 100644
--- a/arch/powerpc/include/asm/eeh.h
+++ b/arch/powerpc/include/asm/eeh.h
@@ -174,6 +174,7 @@ int eeh_rmv_from_parent_pe(struct eeh_dev *edev);
 void *eeh_pe_dev_traverse(struct eeh_pe *root,
                 eeh_traverse_func fn, void *flag);
 void eeh_pe_restore_bars(struct eeh_pe *pe);
+struct pci_bus *eeh_pe_bus_get(struct eeh_pe *pe);
 
 void * __devinit eeh_dev_init(struct device_node *dn, void *data);
 void __devinit eeh_dev_phb_init_dynamic(struct pci_controller *phb);
diff --git a/arch/powerpc/include/asm/eeh_event.h b/arch/powerpc/include/asm/eeh_event.h
index dc722b58216c..de67d830151b 100644
--- a/arch/powerpc/include/asm/eeh_event.h
+++ b/arch/powerpc/include/asm/eeh_event.h
@@ -32,7 +32,7 @@ struct eeh_event {
 };
 
 int eeh_send_failure_event(struct eeh_pe *pe);
-struct eeh_dev *handle_eeh_events(struct eeh_event *);
+void eeh_handle_event(struct eeh_pe *pe);
 
 #endif /* __KERNEL__ */
 #endif /* ASM_POWERPC_EEH_EVENT_H */
diff --git a/arch/powerpc/platforms/pseries/eeh_driver.c b/arch/powerpc/platforms/pseries/eeh_driver.c
index baf92cd9dfab..343c807e608a 100644
--- a/arch/powerpc/platforms/pseries/eeh_driver.c
+++ b/arch/powerpc/platforms/pseries/eeh_driver.c
@@ -116,28 +116,35 @@ static void eeh_enable_irq(struct pci_dev *dev)
 
 /**
  * eeh_report_error - Report pci error to each device driver
- * @dev: PCI device
+ * @data: eeh device
  * @userdata: return value
  * 
  * Report an EEH error to each device driver, collect up and 
  * merge the device driver responses. Cumulative response 
  * passed back in "userdata".
  */
-static int eeh_report_error(struct pci_dev *dev, void *userdata)
+static void *eeh_report_error(void *data, void *userdata)
 {
+        struct eeh_dev *edev = (struct eeh_dev *)data;
+        struct pci_dev *dev = eeh_dev_to_pci_dev(edev);
         enum pci_ers_result rc, *res = userdata;
         struct pci_driver *driver = dev->driver;
 
+        /* We might not have the associated PCI device,
+         * then we should continue for next one.
+         */
+        if (!dev) return NULL;
+
         dev->error_state = pci_channel_io_frozen;
 
         if (!driver)
-                return 0;
+                return NULL;
 
         eeh_disable_irq(dev);
 
         if (!driver->err_handler ||
             !driver->err_handler->error_detected)
-                return 0;
+                return NULL;
 
         rc = driver->err_handler->error_detected(dev, pci_channel_io_frozen);
 
@@ -145,27 +152,31 @@ static int eeh_report_error(struct pci_dev *dev, void *userdata)
         if (rc == PCI_ERS_RESULT_NEED_RESET) *res = rc;
         if (*res == PCI_ERS_RESULT_NONE) *res = rc;
 
-        return 0;
+        return NULL;
 }
 
 /**
  * eeh_report_mmio_enabled - Tell drivers that MMIO has been enabled
- * @dev: PCI device
+ * @data: eeh device
  * @userdata: return value
  *
  * Tells each device driver that IO ports, MMIO and config space I/O
  * are now enabled. Collects up and merges the device driver responses.
  * Cumulative response passed back in "userdata".
  */
-static int eeh_report_mmio_enabled(struct pci_dev *dev, void *userdata)
+static void *eeh_report_mmio_enabled(void *data, void *userdata)
 {
+        struct eeh_dev *edev = (struct eeh_dev *)data;
+        struct pci_dev *dev = eeh_dev_to_pci_dev(edev);
         enum pci_ers_result rc, *res = userdata;
-        struct pci_driver *driver = dev->driver;
+        struct pci_driver *driver;
 
-        if (!driver ||
+        if (!dev) return NULL;
+
+        if (!(driver = dev->driver) ||
             !driver->err_handler ||
             !driver->err_handler->mmio_enabled)
-                return 0;
+                return NULL;
 
         rc = driver->err_handler->mmio_enabled(dev);
 
@@ -173,12 +184,12 @@ static int eeh_report_mmio_enabled(struct pci_dev *dev, void *userdata)
         if (rc == PCI_ERS_RESULT_NEED_RESET) *res = rc;
         if (*res == PCI_ERS_RESULT_NONE) *res = rc;
 
-        return 0;
+        return NULL;
 }
 
 /**
  * eeh_report_reset - Tell device that slot has been reset
- * @dev: PCI device
+ * @data: eeh device
  * @userdata: return value
  *
  * This routine must be called while EEH tries to reset particular
@@ -186,13 +197,15 @@ static int eeh_report_mmio_enabled(struct pci_dev *dev, void *userdata)
  * some actions, usually to save data the driver needs so that the
  * driver can work again while the device is recovered.
  */
-static int eeh_report_reset(struct pci_dev *dev, void *userdata)
+static void *eeh_report_reset(void *data, void *userdata)
 {
+        struct eeh_dev *edev = (struct eeh_dev *)data;
+        struct pci_dev *dev = eeh_dev_to_pci_dev(edev);
         enum pci_ers_result rc, *res = userdata;
-        struct pci_driver *driver = dev->driver;
+        struct pci_driver *driver;
 
-        if (!driver)
-                return 0;
+        if (!dev || !(driver = dev->driver))
+                return NULL;
 
         dev->error_state = pci_channel_io_normal;
 
@@ -200,7 +213,7 @@ static int eeh_report_reset(struct pci_dev *dev, void *userdata)
 
         if (!driver->err_handler ||
             !driver->err_handler->slot_reset)
-                return 0;
+                return NULL;
 
         rc = driver->err_handler->slot_reset(dev);
         if ((*res == PCI_ERS_RESULT_NONE) ||
@@ -208,82 +221,89 @@ static int eeh_report_reset(struct pci_dev *dev, void *userdata)
         if (*res == PCI_ERS_RESULT_DISCONNECT &&
              rc == PCI_ERS_RESULT_NEED_RESET) *res = rc;
 
-        return 0;
+        return NULL;
 }
 
 /**
  * eeh_report_resume - Tell device to resume normal operations
- * @dev: PCI device
+ * @data: eeh device
  * @userdata: return value
  *
  * This routine must be called to notify the device driver that it
  * could resume so that the device driver can do some initialization
  * to make the recovered device work again.
  */
-static int eeh_report_resume(struct pci_dev *dev, void *userdata)
+static void *eeh_report_resume(void *data, void *userdata)
 {
-        struct pci_driver *driver = dev->driver;
+        struct eeh_dev *edev = (struct eeh_dev *)data;
+        struct pci_dev *dev = eeh_dev_to_pci_dev(edev);
+        struct pci_driver *driver;
+
+        if (!dev) return NULL;
 
         dev->error_state = pci_channel_io_normal;
 
-        if (!driver)
-                return 0;
+        if (!(driver = dev->driver))
+                return NULL;
 
         eeh_enable_irq(dev);
 
         if (!driver->err_handler ||
             !driver->err_handler->resume)
-                return 0;
+                return NULL;
 
         driver->err_handler->resume(dev);
 
-        return 0;
+        return NULL;
 }
 
 /**
  * eeh_report_failure - Tell device driver that device is dead.
- * @dev: PCI device
+ * @data: eeh device
  * @userdata: return value
  *
  * This informs the device driver that the device is permanently
  * dead, and that no further recovery attempts will be made on it.
  */
-static int eeh_report_failure(struct pci_dev *dev, void *userdata)
+static void *eeh_report_failure(void *data, void *userdata)
 {
-        struct pci_driver *driver = dev->driver;
+        struct eeh_dev *edev = (struct eeh_dev *)data;
+        struct pci_dev *dev = eeh_dev_to_pci_dev(edev);
+        struct pci_driver *driver;
+
+        if (!dev) return NULL;
 
         dev->error_state = pci_channel_io_perm_failure;
 
-        if (!driver)
-                return 0;
+        if (!(driver = dev->driver))
+                return NULL;
 
         eeh_disable_irq(dev);
 
         if (!driver->err_handler ||
             !driver->err_handler->error_detected)
-                return 0;
+                return NULL;
 
         driver->err_handler->error_detected(dev, pci_channel_io_perm_failure);
 
-        return 0;
+        return NULL;
 }
 
 /**
  * eeh_reset_device - Perform actual reset of a pci slot
- * @edev: PE associated EEH device
+ * @pe: EEH PE
  * @bus: PCI bus corresponding to the isolcated slot
  *
  * This routine must be called to do reset on the indicated PE.
  * During the reset, udev might be invoked because those affected
  * PCI devices will be removed and then added.
  */
-static int eeh_reset_device(struct eeh_dev *edev, struct pci_bus *bus)
+static int eeh_reset_device(struct eeh_pe *pe, struct pci_bus *bus)
 {
-        struct device_node *dn;
         int cnt, rc;
 
         /* pcibios will clear the counter; save the value */
-        cnt = edev->freeze_count;
+        cnt = pe->freeze_count;
 
         if (bus)
                 pcibios_remove_pci_devices(bus);
@@ -292,25 +312,13 @@ static int eeh_reset_device(struct eeh_dev *edev, struct pci_bus *bus)
          * Reconfigure bridges and devices. Don't try to bring the system
          * up if the reset failed for some reason.
          */
-        rc = eeh_reset_pe(edev);
+        rc = eeh_reset_pe(pe);
         if (rc)
                 return rc;
 
-        /* Walk over all functions on this device. */
-        dn = eeh_dev_to_of_node(edev);
-        if (!pcibios_find_pci_bus(dn) && of_node_to_eeh_dev(dn->parent))
-                dn = dn->parent->child;
-
-        while (dn) {
-                struct eeh_dev *pedev = of_node_to_eeh_dev(dn);
-
-                /* On Power4, always true because eeh_pe_config_addr=0 */
-                if (edev->pe_config_addr == pedev->pe_config_addr) {
-                        eeh_ops->configure_bridge(dn);
-                        eeh_restore_bars(pedev);
-                }
-                dn = dn->sibling;
-        }
+        /* Restore PE */
+        eeh_ops->configure_bridge(pe);
+        eeh_pe_restore_bars(pe);
 
         /* Give the system 5 seconds to finish running the user-space
          * hotplug shutdown scripts, e.g. ifdown for ethernet.  Yes, 
@@ -322,7 +330,7 @@ static int eeh_reset_device(struct eeh_dev *edev, struct pci_bus *bus)
                 ssleep(5);
                 pcibios_add_pci_devices(bus);
         }
-        edev->freeze_count = cnt;
+        pe->freeze_count = cnt;
 
         return 0;
 }
@@ -334,7 +342,7 @@ static int eeh_reset_device(struct eeh_dev *edev, struct pci_bus *bus)
 
 /**
  * eeh_handle_event - Reset a PCI device after hard lockup.
- * @event: EEH event
+ * @pe: EEH PE
  *
  * While PHB detects address or data parity errors on particular PCI
  * slot, the associated PE will be frozen. Besides, DMA's occurring
@@ -349,69 +357,24 @@ static int eeh_reset_device(struct eeh_dev *edev, struct pci_bus *bus)
  * drivers (which cause a second set of hotplug events to go out to
  * userspace).
  */
-struct eeh_dev *handle_eeh_events(struct eeh_event *event)
+void eeh_handle_event(struct eeh_pe *pe)
 {
-        struct device_node *frozen_dn;
-        struct eeh_dev *frozen_edev;
         struct pci_bus *frozen_bus;
         int rc = 0;
         enum pci_ers_result result = PCI_ERS_RESULT_NONE;
-        const char *location, *pci_str, *drv_str, *bus_pci_str, *bus_drv_str;
-
-        frozen_dn = eeh_find_device_pe(eeh_dev_to_of_node(event->edev));
-        if (!frozen_dn) {
-                location = of_get_property(eeh_dev_to_of_node(event->edev), "ibm,loc-code", NULL);
-                location = location ? location : "unknown";
-                printk(KERN_ERR "EEH: Error: Cannot find partition endpoint "
-                                "for location=%s pci addr=%s\n",
-                        location, eeh_pci_name(eeh_dev_to_pci_dev(event->edev)));
-                return NULL;
-        }
-
-        frozen_bus = pcibios_find_pci_bus(frozen_dn);
-        location = of_get_property(frozen_dn, "ibm,loc-code", NULL);
-        location = location ? location : "unknown";
-
-        /* 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);
 
+        frozen_bus = eeh_pe_bus_get(pe);
         if (!frozen_bus) {
-                printk(KERN_ERR "EEH: Cannot find PCI bus "
-                        "for location=%s dn=%s\n",
-                        location, frozen_dn->full_name);
-                return NULL;
+                pr_err("%s: Cannot find PCI bus for PHB#%d-PE#%x\n",
+                        __func__, pe->phb->global_number, pe->addr);
+                return;
         }
 
-        frozen_edev = of_node_to_eeh_dev(frozen_dn);
-        frozen_edev->freeze_count++;
-        pci_str = eeh_pci_name(eeh_dev_to_pci_dev(event->edev));
-        drv_str = eeh_pcid_name(eeh_dev_to_pci_dev(event->edev));
-
-        if (frozen_edev->freeze_count > EEH_MAX_ALLOWED_FREEZES)
+        pe->freeze_count++;
+        if (pe->freeze_count > EEH_MAX_ALLOWED_FREEZES)
                 goto excess_failures;
-
-        printk(KERN_WARNING
-           "EEH: This PCI device has failed %d times in the last hour:\n",
-                frozen_edev->freeze_count);
-
-        if (frozen_edev->pdev) {
-                bus_pci_str = pci_name(frozen_edev->pdev);
-                bus_drv_str = eeh_pcid_name(frozen_edev->pdev);
-                printk(KERN_WARNING
-                        "EEH: Bus location=%s driver=%s pci addr=%s\n",
-                        location, bus_drv_str, bus_pci_str);
-        }
-
-        printk(KERN_WARNING
-                "EEH: Device location=%s driver=%s pci addr=%s\n",
-                location, drv_str, pci_str);
+        pr_warning("EEH: This PCI device has failed %d times in the last hour\n",
+                pe->freeze_count);
 
         /* Walk the various device drivers attached to this slot through
          * a reset sequence, giving each an opportunity to do what it needs
@@ -419,12 +382,12 @@ struct eeh_dev *handle_eeh_events(struct eeh_event *event)
          * 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);
+        eeh_pe_dev_traverse(pe, eeh_report_error, &result);
 
         /* Get the current PCI slot state. This can take a long time,
          * sometimes over 3 seconds for certain systems.
          */
-        rc = eeh_ops->wait_state(eeh_dev_to_of_node(frozen_edev), MAX_WAIT_FOR_RECOVERY*1000);
+        rc = eeh_ops->wait_state(pe, MAX_WAIT_FOR_RECOVERY*1000);
         if (rc < 0 || rc == EEH_STATE_NOT_SUPPORT) {
                 printk(KERN_WARNING "EEH: Permanent failure\n");
                 goto hard_fail;
@@ -434,14 +397,14 @@ struct eeh_dev *handle_eeh_events(struct eeh_event *event)
          * don't post the error log until after all dev drivers
          * have been informed.
          */
-        eeh_slot_error_detail(frozen_edev, EEH_LOG_TEMP);
+        eeh_slot_error_detail(pe, EEH_LOG_TEMP);
 
         /* 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_edev, frozen_bus);
+                rc = eeh_reset_device(pe, frozen_bus);
                 if (rc) {
                         printk(KERN_WARNING "EEH: Unable to reset, rc=%d\n", rc);
                         goto hard_fail;
@@ -450,7 +413,7 @@ struct eeh_dev *handle_eeh_events(struct eeh_event *event)
 
         /* If all devices reported they can proceed, then re-enable MMIO */
         if (result == PCI_ERS_RESULT_CAN_RECOVER) {
-                rc = eeh_pci_enable(frozen_edev, EEH_OPT_THAW_MMIO);
+                rc = eeh_pci_enable(pe, EEH_OPT_THAW_MMIO);
 
                 if (rc < 0)
                         goto hard_fail;
@@ -458,13 +421,13 @@ struct eeh_dev *handle_eeh_events(struct eeh_event *event)
                         result = PCI_ERS_RESULT_NEED_RESET;
                 } else {
                         result = PCI_ERS_RESULT_NONE;
-                        pci_walk_bus(frozen_bus, eeh_report_mmio_enabled, &result);
+                        eeh_pe_dev_traverse(pe, eeh_report_mmio_enabled, &result);
                 }
         }
 
         /* If all devices reported they can proceed, then re-enable DMA */
         if (result == PCI_ERS_RESULT_CAN_RECOVER) {
-                rc = eeh_pci_enable(frozen_edev, EEH_OPT_THAW_DMA);
+                rc = eeh_pci_enable(pe, EEH_OPT_THAW_DMA);
 
                 if (rc < 0)
                         goto hard_fail;
@@ -482,13 +445,13 @@ struct eeh_dev *handle_eeh_events(struct eeh_event *event)
 
         /* If any device called out for a reset, then reset the slot */
         if (result == PCI_ERS_RESULT_NEED_RESET) {
-                rc = eeh_reset_device(frozen_edev, NULL);
+                rc = eeh_reset_device(pe, NULL);
                 if (rc) {
                         printk(KERN_WARNING "EEH: Cannot reset, rc=%d\n", rc);
                         goto hard_fail;
                 }
                 result = PCI_ERS_RESULT_NONE;
-                pci_walk_bus(frozen_bus, eeh_report_reset, &result);
+                eeh_pe_dev_traverse(pe, eeh_report_reset, &result);
         }
 
         /* All devices should claim they have recovered by now. */
@@ -499,9 +462,9 @@ struct eeh_dev *handle_eeh_events(struct eeh_event *event)
         }
 
         /* Tell all device drivers that they can resume operations */
-        pci_walk_bus(frozen_bus, eeh_report_resume, NULL);
+        eeh_pe_dev_traverse(pe, eeh_report_resume, NULL);
 
-        return frozen_edev;
+        return;
         
 excess_failures:
         /*
@@ -509,30 +472,26 @@ excess_failures:
          * are due to poorly seated PCI cards. Only 10% or so are
          * due to actual, failed cards.
          */
-        printk(KERN_ERR
-           "EEH: PCI device at location=%s driver=%s pci addr=%s\n"
-                "has failed %d times in the last hour "
-                "and has been permanently disabled.\n"
-                "Please try reseating this device or replacing it.\n",
-                location, drv_str, pci_str, frozen_edev->freeze_count);
+        pr_err("EEH: PHB#%d-PE#%x has failed %d times in the\n"
+               "last hour and has been permanently disabled.\n"
+               "Please try reseating or replacing it.\n",
+                pe->phb->global_number, pe->addr,
+                pe->freeze_count);
         goto perm_error;
 
 hard_fail:
-        printk(KERN_ERR
-           "EEH: Unable to recover from failure of PCI device "
-           "at location=%s driver=%s pci addr=%s\n"
-           "Please try reseating this device or replacing it.\n",
-                location, drv_str, pci_str);
+        pr_err("EEH: Unable to recover from failure from PHB#%d-PE#%x.\n"
+               "Please try reseating or replacing it\n",
+                pe->phb->global_number, pe->addr);
 
 perm_error:
-        eeh_slot_error_detail(frozen_edev, EEH_LOG_PERM);
+        eeh_slot_error_detail(pe, EEH_LOG_PERM);
 
         /* Notify all devices that they're about to go down. */
-        pci_walk_bus(frozen_bus, eeh_report_failure, NULL);
+        eeh_pe_dev_traverse(pe, eeh_report_failure, NULL);
 
         /* Shut down the device drivers for good. */
-        pcibios_remove_pci_devices(frozen_bus);
-
-        return NULL;
+        if (frozen_bus)
+                pcibios_remove_pci_devices(frozen_bus);
 }
 
diff --git a/arch/powerpc/platforms/pseries/eeh_event.c b/arch/powerpc/platforms/pseries/eeh_event.c
index ba7005a5e2fe..51faaac8abe6 100644
--- a/arch/powerpc/platforms/pseries/eeh_event.c
+++ b/arch/powerpc/platforms/pseries/eeh_event.c
@@ -82,7 +82,7 @@ static int eeh_event_handler(void * dummy)
                 pe->phb->global_number, pe->addr);
 
         set_current_state(TASK_INTERRUPTIBLE);  /* Don't add to load average */
-        handle_eeh_events(event);
+        eeh_handle_event(pe);
         eeh_pe_state_clear(pe, EEH_PE_RECOVERING);
 
         kfree(event);
diff --git a/arch/powerpc/platforms/pseries/eeh_pe.c b/arch/powerpc/platforms/pseries/eeh_pe.c
index 2b7e85b804a4..904123c7657b 100644
--- a/arch/powerpc/platforms/pseries/eeh_pe.c
+++ b/arch/powerpc/platforms/pseries/eeh_pe.c
@@ -561,3 +561,31 @@ void eeh_pe_restore_bars(struct eeh_pe *pe)
 {
         eeh_pe_dev_traverse(pe, eeh_restore_one_device_bars, NULL);
 }
+
+/**
+ * eeh_pe_bus_get - Retrieve PCI bus according to the given PE
+ * @pe: EEH PE
+ *
+ * Retrieve the PCI bus according to the given PE. Basically,
+ * there're 3 types of PEs: PHB/Bus/Device. For PHB PE, the
+ * primary PCI bus will be retrieved. The parent bus will be
+ * returned for BUS PE. However, we don't have associated PCI
+ * bus for DEVICE PE.
+ */
+struct pci_bus *eeh_pe_bus_get(struct eeh_pe *pe)
+{
+        struct pci_bus *bus = NULL;
+        struct eeh_dev *edev;
+        struct pci_dev *pdev;
+
+        if (pe->type == EEH_PE_PHB) {
+                bus = pe->phb->bus;
+        } else if (pe->type == EEH_PE_BUS) {
+                edev = list_first_entry(&pe->edevs, struct eeh_dev, list);
+                pdev = eeh_dev_to_pci_dev(edev);
+                if (pdev)
+                        bus = pdev->bus;
+        }
+
+        return bus;
+}