arch/powerpc/kernel/pci_dn.c

   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 }