LXR linux/arch/powerpc/platforms/pseries/pci

   1/*
   2 * PCI Dynamic LPAR, PCI Hot Plug and PCI EEH recovery code
   3 * for RPA-compliant PPC64 platform.
   4 * Copyright (C) 2003 Linda Xie <lxie@us.ibm.com>
   5 * Copyright (C) 2005 International Business Machines
   6 *
   7 * Updates, 2005, John Rose <johnrose@austin.ibm.com>
   8 * Updates, 2005, Linas Vepstas <linas@austin.ibm.com>
   9 *
  10 * All rights reserved.
  11 *
  12 * This program is free software; you can redistribute it and/or modify
  13 * it under the terms of the GNU General Public License as published by
  14 * the Free Software Foundation; either version 2 of the License, or (at
  15 * your option) any later version.
  16 *
  17 * This program is distributed in the hope that it will be useful, but
  18 * WITHOUT ANY WARRANTY; without even the implied warranty of
  19 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
  20 * NON INFRINGEMENT.  See the GNU General Public License for more
  21 * details.
  22 *
  23 * You should have received a copy of the GNU General Public License
  24 * along with this program; if not, write to the Free Software
  25 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  26 */
  27
  28#include <linux/pci.h>
  29#include <linux/export.h>
  30#include <asm/pci-bridge.h>
  31#include <asm/ppc-pci.h>
  32#include <asm/firmware.h>
  33#include <asm/eeh.h>
  34
  35#include "pseries.h"
  36
  37static struct pci_bus *
  38find_bus_among_children(struct pci_bus *bus,
  39                        struct device_node *dn)
  40{
  41        struct pci_bus *child = NULL;
  42        struct pci_bus *tmp;
  43        struct device_node *busdn;
  44
  45        busdn = pci_bus_to_OF_node(bus);
  46        if (busdn == dn)
  47                return bus;
  48
  49        list_for_each_entry(tmp, &bus->children, node) {
  50                child = find_bus_among_children(tmp, dn);
  51                if (child)
  52                        break;
  53        };
  54        return child;
  55}
  56
  57struct pci_bus *
  58pcibios_find_pci_bus(struct device_node *dn)
  59{
  60        struct pci_dn *pdn = dn->data;
  61
  62        if (!pdn  || !pdn->phb || !pdn->phb->bus)
  63                return NULL;
  64
  65        return find_bus_among_children(pdn->phb->bus, dn);
  66}
  67EXPORT_SYMBOL_GPL(pcibios_find_pci_bus);
  68
  69struct pci_controller *init_phb_dynamic(struct device_node *dn)
  70{
  71        struct pci_controller *phb;
  72
  73        pr_debug("PCI: Initializing new hotplug PHB %s\n", dn->full_name);
  74
  75        phb = pcibios_alloc_controller(dn);
  76        if (!phb)
  77                return NULL;
  78        rtas_setup_phb(phb);
  79        pci_process_bridge_OF_ranges(phb, dn, 0);
  80        phb->controller_ops = pseries_pci_controller_ops;
  81
  82        pci_devs_phb_init_dynamic(phb);
  83
  84        /* Create EEH devices for the PHB */
  85        eeh_dev_phb_init_dynamic(phb);
  86
  87        if (dn->child)
  88                eeh_add_device_tree_early(PCI_DN(dn));
  89
  90        pcibios_scan_phb(phb);
  91        pcibios_finish_adding_to_bus(phb->bus);
  92
  93        return phb;
  94}
  95EXPORT_SYMBOL_GPL(init_phb_dynamic);
  96
  97/* RPA-specific bits for removing PHBs */
  98int remove_phb_dynamic(struct pci_controller *phb)
  99{
 100        struct pci_bus *b = phb->bus;
 101        struct resource *res;
 102        int rc, i;
 103
 104        pr_debug("PCI: Removing PHB %04x:%02x...\n",
 105                 pci_domain_nr(b), b->number);
 106
 107        /* We cannot to remove a root bus that has children */
 108        if (!(list_empty(&b->children) && list_empty(&b->devices)))
 109                return -EBUSY;
 110
 111        /* We -know- there aren't any child devices anymore at this stage
 112         * and thus, we can safely unmap the IO space as it's not in use
 113         */
 114        res = &phb->io_resource;
 115        if (res->flags & IORESOURCE_IO) {
 116                rc = pcibios_unmap_io_space(b);
 117                if (rc) {
 118                        printk(KERN_ERR "%s: failed to unmap IO on bus %s\n",
 119                               __func__, b->name);
 120                        return 1;
 121                }
 122        }
 123
 124        /* Remove the PCI bus and unregister the bridge device from sysfs */
 125        phb->bus = NULL;
 126        pci_remove_bus(b);
 127        device_unregister(b->bridge);
 128
 129        /* Now release the IO resource */
 130        if (res->flags & IORESOURCE_IO)
 131                release_resource(res);
 132
 133        /* Release memory resources */
 134        for (i = 0; i < 3; ++i) {
 135                res = &phb->mem_resources[i];
 136                if (!(res->flags & IORESOURCE_MEM))
 137                        continue;
 138                release_resource(res);
 139        }
 140
 141        /*
 142         * The pci_controller data structure is freed by
 143         * the pcibios_free_controller_deferred() callback;
 144         * see pseries_root_bridge_prepare().
 145         */
 146
 147        return 0;
 148}
 149EXPORT_SYMBOL_GPL(remove_phb_dynamic);
 150