/* * The file intends to implement PE based on the information from * platforms. Basically, there have 3 types of PEs: PHB/Bus/Device. * All the PEs should be organized as hierarchy tree. The first level * of the tree will be associated to existing PHBs since the particular * PE is only meaningful in one PHB domain. * * Copyright Benjamin Herrenschmidt & Gavin Shan, IBM Corporation 2012. * * 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 #include #include #include #include #include #include #include static LIST_HEAD(eeh_phb_pe); /** * eeh_pe_alloc - Allocate PE * @phb: PCI controller * @type: PE type * * Allocate PE instance dynamically. */ static struct eeh_pe *eeh_pe_alloc(struct pci_controller *phb, int type) { struct eeh_pe *pe; /* Allocate PHB PE */ pe = kzalloc(sizeof(struct eeh_pe), GFP_KERNEL); if (!pe) return NULL; /* Initialize PHB PE */ pe->type = type; pe->phb = phb; INIT_LIST_HEAD(&pe->child_list); INIT_LIST_HEAD(&pe->child); INIT_LIST_HEAD(&pe->edevs); return pe; } /** * eeh_phb_pe_create - Create PHB PE * @phb: PCI controller * * The function should be called while the PHB is detected during * system boot or PCI hotplug in order to create PHB PE. */ int __devinit eeh_phb_pe_create(struct pci_controller *phb) { struct eeh_pe *pe; /* Allocate PHB PE */ pe = eeh_pe_alloc(phb, EEH_PE_PHB); if (!pe) { pr_err("%s: out of memory!\n", __func__); return -ENOMEM; } /* Put it into the list */ eeh_lock(); list_add_tail(&pe->child, &eeh_phb_pe); eeh_unlock(); pr_debug("EEH: Add PE for PHB#%d\n", phb->global_number); return 0; } /** * eeh_phb_pe_get - Retrieve PHB PE based on the given PHB * @phb: PCI controller * * The overall PEs form hierarchy tree. The first layer of the * hierarchy tree is composed of PHB PEs. The function is used * to retrieve the corresponding PHB PE according to the given PHB. */ static struct eeh_pe *eeh_phb_pe_get(struct pci_controller *phb) { struct eeh_pe *pe; eeh_lock(); list_for_each_entry(pe, &eeh_phb_pe, child) { /* * Actually, we needn't check the type since * the PE for PHB has been determined when that * was created. */ if (pe->type == EEH_PE_PHB && pe->phb == phb) { eeh_unlock(); return pe; } } eeh_unlock(); return NULL; } /** * eeh_pe_next - Retrieve the next PE in the tree * @pe: current PE * @root: root PE * * The function is used to retrieve the next PE in the * hierarchy PE tree. */ static struct eeh_pe *eeh_pe_next(struct eeh_pe *pe, struct eeh_pe *root) { struct list_head *next = pe->child_list.next; if (next == &pe->child_list) { while (1) { if (pe == root) return NULL; next = pe->child.next; if (next != &pe->parent->child_list) break; pe = pe->parent; } } return list_entry(next, struct eeh_pe, child); } /** * eeh_pe_traverse - Traverse PEs in the specified PHB * @root: root PE * @fn: callback * @flag: extra parameter to callback * * The function is used to traverse the specified PE and its * child PEs. The traversing is to be terminated once the * callback returns something other than NULL, or no more PEs * to be traversed. */ static void *eeh_pe_traverse(struct eeh_pe *root, eeh_traverse_func fn, void *flag) { struct eeh_pe *pe; void *ret; for (pe = root; pe; pe = eeh_pe_next(pe, root)) { ret = fn(pe, flag); if (ret) return ret; } return NULL; } /** * __eeh_pe_get - Check the PE address * @data: EEH PE * @flag: EEH device * * For one particular PE, it can be identified by PE address * or tranditional BDF address. BDF address is composed of * Bus/Device/Function number. The extra data referred by flag * indicates which type of address should be used. */ static void *__eeh_pe_get(void *data, void *flag) { struct eeh_pe *pe = (struct eeh_pe *)data; struct eeh_dev *edev = (struct eeh_dev *)flag; /* Unexpected PHB PE */ if (pe->type == EEH_PE_PHB) return NULL; /* We prefer PE address */ if (edev->pe_config_addr && (edev->pe_config_addr == pe->addr)) return pe; /* Try BDF address */ if (edev->pe_config_addr && (edev->config_addr == pe->config_addr)) return pe; return NULL; } /** * eeh_pe_get - Search PE based on the given address * @edev: EEH device * * Search the corresponding PE based on the specified address which * is included in the eeh device. The function is used to check if * the associated PE has been created against the PE address. It's * notable that the PE address has 2 format: traditional PE address * which is composed of PCI bus/device/function number, or unified * PE address. */ static struct eeh_pe *eeh_pe_get(struct eeh_dev *edev) { struct eeh_pe *root = eeh_phb_pe_get(edev->phb); struct eeh_pe *pe; eeh_lock(); pe = eeh_pe_traverse(root, __eeh_pe_get, edev); eeh_unlock(); return pe; } /** * eeh_pe_get_parent - Retrieve the parent PE * @edev: EEH device * * The whole PEs existing in the system are organized as hierarchy * tree. The function is used to retrieve the parent PE according * to the parent EEH device. */ static struct eeh_pe *eeh_pe_get_parent(struct eeh_dev *edev) { struct device_node *dn; struct eeh_dev *parent; /* * It might have the case for the indirect parent * EEH device already having associated PE, but * the direct parent EEH device doesn't have yet. */ dn = edev->dn->parent; while (dn) { /* We're poking out of PCI territory */ if (!PCI_DN(dn)) return NULL; parent = of_node_to_eeh_dev(dn); /* We're poking out of PCI territory */ if (!parent) return NULL; if (parent->pe) return parent->pe; dn = dn->parent; } 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; }