1 /* 2 * pci_dn.c 3 * 4 * Copyright (C) 2001 Todd Inglett, IBM Corporation 5 * 6 * PCI manipulation via device_nodes. 7 * 8 * This program is free software; you can redistribute it and/or modify 9 * it under the terms of the GNU General Public License as published by 10 * the Free Software Foundation; either version 2 of the License, or 11 * (at your option) any later version. 12 * 13 * This program is distributed in the hope that it will be useful, 14 * but WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 * GNU General Public License for more details. 17 * 18 * You should have received a copy of the GNU General Public License 19 * along with this program; if not, write to the Free Software 20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 21 */ 22 #include <linux/kernel.h> 23 #include <linux/pci.h> 24 #include <linux/string.h> 25 #include <linux/export.h> 26 #include <linux/init.h> 27 #include <linux/gfp.h> 28 29 #include <asm/io.h> 30 #include <asm/prom.h> 31 #include <asm/pci-bridge.h> 32 #include <asm/ppc-pci.h> 33 #include <asm/firmware.h> 34 35 struct pci_dn *pci_get_pdn(struct pci_dev *pdev) 36 { 37 struct device_node *dn = pci_device_to_OF_node(pdev); 38 if (!dn) 39 return NULL; 40 return PCI_DN(dn); 41 } 42 43 /* 44 * Traverse_func that inits the PCI fields of the device node. 45 * NOTE: this *must* be done before read/write config to the device. 46 */ 47 void *update_dn_pci_info(struct device_node *dn, void *data) 48 { 49 struct pci_controller *phb = data; 50 const __be32 *type = of_get_property(dn, "ibm,pci-config-space-type", NULL); 51 const __be32 *regs; 52 struct pci_dn *pdn; 53 54 pdn = zalloc_maybe_bootmem(sizeof(*pdn), GFP_KERNEL); 55 if (pdn == NULL) 56 return NULL; 57 dn->data = pdn; 58 pdn->node = dn; 59 pdn->phb = phb; 60 #ifdef CONFIG_PPC_POWERNV 61 pdn->pe_number = IODA_INVALID_PE; 62 #endif 63 regs = of_get_property(dn, "reg", NULL); 64 if (regs) { 65 u32 addr = of_read_number(regs, 1); 66 67 /* First register entry is addr (00BBSS00) */ 68 pdn->busno = (addr >> 16) & 0xff; 69 pdn->devfn = (addr >> 8) & 0xff; 70 } 71 72 pdn->pci_ext_config_space = (type && of_read_number(type, 1) == 1); 73 return NULL; 74 } 75 76 /* 77 * Traverse a device tree stopping each PCI device in the tree. 78 * This is done depth first. As each node is processed, a "pre" 79 * function is called and the children are processed recursively. 80 * 81 * The "pre" func returns a value. If non-zero is returned from 82 * the "pre" func, the traversal stops and this value is returned. 83 * This return value is useful when using traverse as a method of 84 * finding a device. 85 * 86 * NOTE: we do not run the func for devices that do not appear to 87 * be PCI except for the start node which we assume (this is good 88 * because the start node is often a phb which may be missing PCI 89 * properties). 90 * We use the class-code as an indicator. If we run into 91 * one of these nodes we also assume its siblings are non-pci for 92 * performance. 93 */ 94 void *traverse_pci_devices(struct device_node *start, traverse_func pre, 95 void *data) 96 { 97 struct device_node *dn, *nextdn; 98 void *ret; 99 100 /* We started with a phb, iterate all childs */ 101 for (dn = start->child; dn; dn = nextdn) { 102 const __be32 *classp; 103 u32 class = 0; 104 105 nextdn = NULL; 106 classp = of_get_property(dn, "class-code", NULL); 107 if (classp) 108 class = of_read_number(classp, 1); 109 110 if (pre && ((ret = pre(dn, data)) != NULL)) 111 return ret; 112 113 /* If we are a PCI bridge, go down */ 114 if (dn->child && ((class >> 8) == PCI_CLASS_BRIDGE_PCI || 115 (class >> 8) == PCI_CLASS_BRIDGE_CARDBUS)) 116 /* Depth first...do children */ 117 nextdn = dn->child; 118 else if (dn->sibling) 119 /* ok, try next sibling instead. */ 120 nextdn = dn->sibling; 121 if (!nextdn) { 122 /* Walk up to next valid sibling. */ 123 do { 124 dn = dn->parent; 125 if (dn == start) 126 return NULL; 127 } while (dn->sibling == NULL); 128 nextdn = dn->sibling; 129 } 130 } 131 return NULL; 132 } 133 134 /** 135 * pci_devs_phb_init_dynamic - setup pci devices under this PHB 136 * phb: pci-to-host bridge (top-level bridge connecting to cpu) 137 * 138 * This routine is called both during boot, (before the memory 139 * subsystem is set up, before kmalloc is valid) and during the 140 * dynamic lpar operation of adding a PHB to a running system. 141 */ 142 void pci_devs_phb_init_dynamic(struct pci_controller *phb) 143 { 144 struct device_node *dn = phb->dn; 145 struct pci_dn *pdn; 146 147 /* PHB nodes themselves must not match */ 148 update_dn_pci_info(dn, phb); 149 pdn = dn->data; 150 if (pdn) { 151 pdn->devfn = pdn->busno = -1; 152 pdn->phb = phb; 153 } 154 155 /* Update dn->phb ptrs for new phb and children devices */ 156 traverse_pci_devices(dn, update_dn_pci_info, phb); 157 } 158 159 /** 160 * pci_devs_phb_init - Initialize phbs and pci devs under them. 161 * 162 * This routine walks over all phb's (pci-host bridges) on the 163 * system, and sets up assorted pci-related structures 164 * (including pci info in the device node structs) for each 165 * pci device found underneath. This routine runs once, 166 * early in the boot sequence. 167 */ 168 void __init pci_devs_phb_init(void) 169 { 170 struct pci_controller *phb, *tmp; 171 172 /* This must be done first so the device nodes have valid pci info! */ 173 list_for_each_entry_safe(phb, tmp, &hose_list, list_node) 174 pci_devs_phb_init_dynamic(phb); 175 } 176