powerpc/eeh: Create PEs duing EEH initialization

The patch creates PEs and associated the newly created PEs with
it parent/silbing as well as EEH devices. It would become more
straight to trace EEH errors and recover them accordingly.

Once the EEH functionality on one PCI IOA has been enabled, we
tries to create PE against it. If there's existing PE, to which
the current PCI IOA should be attached, the existing PE will be
converted from "device" type to "bus" type accordingly.

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

3 files changed, 87 insertions, 0 deletions

diff --git a/arch/powerpc/include/asm/eeh.h b/arch/powerpc/include/asm/eeh.h
index 1cc1388d6201..6b13790fdadb 100644
--- a/arch/powerpc/include/asm/eeh.h
+++ b/arch/powerpc/include/asm/eeh.h
@@ -166,6 +166,7 @@ static inline void eeh_unlock(void)
 
 typedef void *(*eeh_traverse_func)(void *data, void *flag);
 int __devinit eeh_phb_pe_create(struct pci_controller *phb);
+int eeh_add_to_parent_pe(struct eeh_dev *edev);
 
 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/platforms/pseries/eeh.c b/arch/powerpc/platforms/pseries/eeh.c
index 0ba7e3b84672..8f2149061846 100644
--- a/arch/powerpc/platforms/pseries/eeh.c
+++ b/arch/powerpc/platforms/pseries/eeh.c
@@ -895,6 +895,8 @@ static void *eeh_early_enable(struct device_node *dn, void *data)
                         eeh_subsystem_enabled = 1;
                         edev->mode |= EEH_MODE_SUPPORTED;
 
+                        eeh_add_to_parent_pe(edev);
+
                         pr_debug("EEH: %s: eeh enabled, config=%x pe_config=%x\n",
                                  dn->full_name, edev->config_addr,
                                  edev->pe_config_addr);
@@ -908,6 +910,10 @@ static void *eeh_early_enable(struct device_node *dn, void *data)
                                 /* Parent supports EEH. */
                                 edev->mode |= EEH_MODE_SUPPORTED;
                                 edev->config_addr = of_node_to_eeh_dev(dn->parent)->config_addr;
+                                edev->pe_config_addr = of_node_to_eeh_dev(dn->parent)->pe_config_addr;
+
+                                eeh_add_to_parent_pe(edev);
+
                                 return NULL;
                         }
                 }
diff --git a/arch/powerpc/platforms/pseries/eeh_pe.c b/arch/powerpc/platforms/pseries/eeh_pe.c
index f74b350c392d..1d632739d28e 100644
--- a/arch/powerpc/platforms/pseries/eeh_pe.c
+++ b/arch/powerpc/platforms/pseries/eeh_pe.c
@@ -261,3 +261,83 @@ static struct eeh_pe *eeh_pe_get_parent(struct eeh_dev *edev)
 
         return NULL;
 }
+
+/**
+ * eeh_add_to_parent_pe - Add EEH device to parent PE
+ * @edev: EEH device
+ *
+ * Add EEH device to the parent PE. If the parent PE already
+ * exists, the PE type will be changed to EEH_PE_BUS. Otherwise,
+ * we have to create new PE to hold the EEH device and the new
+ * PE will be linked to its parent PE as well.
+ */
+int eeh_add_to_parent_pe(struct eeh_dev *edev)
+{
+        struct eeh_pe *pe, *parent;
+
+        /*
+         * Search the PE has been existing or not according
+         * to the PE address. If that has been existing, the
+         * PE should be composed of PCI bus and its subordinate
+         * components.
+         */
+        pe = eeh_pe_get(edev);
+        if (pe) {
+                if (!edev->pe_config_addr) {
+                        pr_err("%s: PE with addr 0x%x already exists\n",
+                                __func__, edev->config_addr);
+                        return -EEXIST;
+                }
+
+                /* Mark the PE as type of PCI bus */
+                pe->type = EEH_PE_BUS;
+                edev->pe = pe;
+
+                /* Put the edev to PE */
+                list_add_tail(&edev->list, &pe->edevs);
+                pr_debug("EEH: Add %s to Bus PE#%x\n",
+                        edev->dn->full_name, pe->addr);
+
+                return 0;
+        }
+
+        /* Create a new EEH PE */
+        pe = eeh_pe_alloc(edev->phb, EEH_PE_DEVICE);
+        if (!pe) {
+                pr_err("%s: out of memory!\n", __func__);
+                return -ENOMEM;
+        }
+        pe->addr        = edev->pe_config_addr;
+        pe->config_addr = edev->config_addr;
+
+        /*
+         * Put the new EEH PE into hierarchy tree. If the parent
+         * can't be found, the newly created PE will be attached
+         * to PHB directly. Otherwise, we have to associate the
+         * PE with its parent.
+         */
+        parent = eeh_pe_get_parent(edev);
+        if (!parent) {
+                parent = eeh_phb_pe_get(edev->phb);
+                if (!parent) {
+                        pr_err("%s: No PHB PE is found (PHB Domain=%d)\n",
+                                __func__, edev->phb->global_number);
+                        edev->pe = NULL;
+                        kfree(pe);
+                        return -EEXIST;
+                }
+        }
+        pe->parent = parent;
+
+        /*
+         * Put the newly created PE into the child list and
+         * link the EEH device accordingly.
+         */
+        list_add_tail(&pe->child, &parent->child_list);
+        list_add_tail(&edev->list, &pe->edevs);
+        edev->pe = pe;
+        pr_debug("EEH: Add %s to Device PE#%x, Parent PE#%x\n",
+                edev->dn->full_name, pe->addr, pe->parent->addr);
+
+        return 0;
+}