1 /* 2 * PCI <-> OF mapping helpers 3 * 4 * Copyright 2011 IBM Corp. 5 * 6 * This program is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU General Public License 8 * as published by the Free Software Foundation; either version 9 * 2 of the License, or (at your option) any later version. 10 */ 11 12 #include <linux/irqdomain.h> 13 #include <linux/kernel.h> 14 #include <linux/pci.h> 15 #include <linux/of.h> 16 #include <linux/of_irq.h> 17 #include <linux/of_pci.h> 18 #include "pci.h" 19 20 void pci_set_of_node(struct pci_dev *dev) 21 { 22 if (!dev->bus->dev.of_node) 23 return; 24 dev->dev.of_node = of_pci_find_child_device(dev->bus->dev.of_node, 25 dev->devfn); 26 } 27 28 void pci_release_of_node(struct pci_dev *dev) 29 { 30 of_node_put(dev->dev.of_node); 31 dev->dev.of_node = NULL; 32 } 33 34 void pci_set_bus_of_node(struct pci_bus *bus) 35 { 36 if (bus->self == NULL) 37 bus->dev.of_node = pcibios_get_phb_of_node(bus); 38 else 39 bus->dev.of_node = of_node_get(bus->self->dev.of_node); 40 } 41 42 void pci_release_bus_of_node(struct pci_bus *bus) 43 { 44 of_node_put(bus->dev.of_node); 45 bus->dev.of_node = NULL; 46 } 47 48 struct device_node * __weak pcibios_get_phb_of_node(struct pci_bus *bus) 49 { 50 /* This should only be called for PHBs */ 51 if (WARN_ON(bus->self || bus->parent)) 52 return NULL; 53 54 /* Look for a node pointer in either the intermediary device we 55 * create above the root bus or it's own parent. Normally only 56 * the later is populated. 57 */ 58 if (bus->bridge->of_node) 59 return of_node_get(bus->bridge->of_node); 60 if (bus->bridge->parent && bus->bridge->parent->of_node) 61 return of_node_get(bus->bridge->parent->of_node); 62 return NULL; 63 } 64 65 struct irq_domain *pci_host_bridge_of_msi_domain(struct pci_bus *bus) 66 { 67 #ifdef CONFIG_IRQ_DOMAIN 68 struct irq_domain *d; 69 70 if (!bus->dev.of_node) 71 return NULL; 72 73 /* Start looking for a phandle to an MSI controller. */ 74 d = of_msi_get_domain(&bus->dev, bus->dev.of_node, DOMAIN_BUS_PCI_MSI); 75 if (d) 76 return d; 77 78 /* 79 * If we don't have an msi-parent property, look for a domain 80 * directly attached to the host bridge. 81 */ 82 d = irq_find_matching_host(bus->dev.of_node, DOMAIN_BUS_PCI_MSI); 83 if (d) 84 return d; 85 86 return irq_find_host(bus->dev.of_node); 87 #else 88 return NULL; 89 #endif 90 } 91