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 int *type = 51 of_get_property(dn, "ibm,pci-config-space-type", NULL); 52 const u32 *regs; 53 struct pci_dn *pdn; 54 55 pdn = zalloc_maybe_bootmem(sizeof(*pdn), GFP_KERNEL); 56 if (pdn == NULL) 57 return NULL; 58 dn->data = pdn; 59 pdn->node = dn; 60 pdn->phb = phb; 61 #ifdef CONFIG_PPC_POWERNV 62 pdn->pe_number = IODA_INVALID_PE; 63 #endif 64 regs = of_get_property(dn, "reg", NULL); 65 if (regs) { 66 /* First register entry is addr (00BBSS00) */ 67 pdn->busno = (regs[0] >> 16) & 0xff; 68 pdn->devfn = (regs[0] >> 8) & 0xff; 69 } 70 71 pdn->pci_ext_config_space = (type && *type == 1); 72 return NULL; 73 } 74 75 /* 76 * Traverse a device tree stopping each PCI device in the tree. 77 * This is done depth first. As each node is processed, a "pre" 78 * function is called and the children are processed recursively. 79 * 80 * The "pre" func returns a value. If non-zero is returned from 81 * the "pre" func, the traversal stops and this value is returned. 82 * This return value is useful when using traverse as a method of 83 * finding a device. 84 * 85 * NOTE: we do not run the func for devices that do not appear to 86 * be PCI except for the start node which we assume (this is good 87 * because the start node is often a phb which may be missing PCI 88 * properties). 89 * We use the class-code as an indicator. If we run into 90 * one of these nodes we also assume its siblings are non-pci for 91 * performance. 92 */ 93 void *traverse_pci_devices(struct device_node *start, traverse_func pre, 94 void *data) 95 { 96 struct device_node *dn, *nextdn; 97 void *ret; 98 99 /* We started with a phb, iterate all childs */ 100 for (dn = start->child; dn; dn = nextdn) { 101 const u32 *classp; 102 u32 class; 103 104 nextdn = NULL; 105 classp = of_get_property(dn, "class-code", NULL); 106 class = classp ? *classp : 0; 107 108 if (pre && ((ret = pre(dn, data)) != NULL)) 109 return ret; 110 111 /* If we are a PCI bridge, go down */ 112 if (dn->child && ((class >> 8) == PCI_CLASS_BRIDGE_PCI || 113 (class >> 8) == PCI_CLASS_BRIDGE_CARDBUS)) 114 /* Depth first...do children */ 115 nextdn = dn->child; 116 else if (dn->sibling) 117 /* ok, try next sibling instead. */ 118 nextdn = dn->sibling; 119 if (!nextdn) { 120 /* Walk up to next valid sibling. */ 121 do { 122 dn = dn->parent; 123 if (dn == start) 124 return NULL; 125 } while (dn->sibling == NULL); 126 nextdn = dn->sibling; 127 } 128 } 129 return NULL; 130 } 131 132 /** 133 * pci_devs_phb_init_dynamic - setup pci devices under this PHB 134 * phb: pci-to-host bridge (top-level bridge connecting to cpu) 135 * 136 * This routine is called both during boot, (before the memory 137 * subsystem is set up, before kmalloc is valid) and during the 138 * dynamic lpar operation of adding a PHB to a running system. 139 */ 140 void pci_devs_phb_init_dynamic(struct pci_controller *phb) 141 { 142 struct device_node *dn = phb->dn; 143 struct pci_dn *pdn; 144 145 /* PHB nodes themselves must not match */ 146 update_dn_pci_info(dn, phb); 147 pdn = dn->data; 148 if (pdn) { 149 pdn->devfn = pdn->busno = -1; 150 pdn->phb = phb; 151 } 152 153 /* Update dn->phb ptrs for new phb and children devices */ 154 traverse_pci_devices(dn, update_dn_pci_info, phb); 155 } 156 157 /** 158 * pci_devs_phb_init - Initialize phbs and pci devs under them. 159 * 160 * This routine walks over all phb's (pci-host bridges) on the 161 * system, and sets up assorted pci-related structures 162 * (including pci info in the device node structs) for each 163 * pci device found underneath. This routine runs once, 164 * early in the boot sequence. 165 */ 166 void __init pci_devs_phb_init(void) 167 { 168 struct pci_controller *phb, *tmp; 169 170 /* This must be done first so the device nodes have valid pci info! */ 171 list_for_each_entry_safe(phb, tmp, &hose_list, list_node) 172 pci_devs_phb_init_dynamic(phb); 173 } 174