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
  35static struct pci_bus *
  36find_bus_among_children(struct pci_bus *bus,
  37                        struct device_node *dn)
  38{
  39        struct pci_bus *child = NULL;
  40        struct list_head *tmp;
  41        struct device_node *busdn;
  42
  43        busdn = pci_bus_to_OF_node(bus);
  44        if (busdn == dn)
  45                return bus;
  46
  47        list_for_each(tmp, &bus->children) {
  48                child = find_bus_among_children(pci_bus_b(tmp), dn);
  49                if (child)
  50                        break;
  51        };
  52        return child;
  53}
  54
  55struct pci_bus *
  56pcibios_find_pci_bus(struct device_node *dn)
  57{
  58        struct pci_dn *pdn = dn->data;
  59
  60        if (!pdn  || !pdn->phb || !pdn->phb->bus)
  61                return NULL;
  62
  63        return find_bus_among_children(pdn->phb->bus, dn);
  64}
  65EXPORT_SYMBOL_GPL(pcibios_find_pci_bus);
  66
  67struct pci_controller *init_phb_dynamic(struct device_node *dn)
  68{
  69        struct pci_controller *phb;
  70
  71        pr_debug("PCI: Initializing new hotplug PHB %s\n", dn->full_name);
  72
  73        phb = pcibios_alloc_controller(dn);
  74        if (!phb)
  75                return NULL;
  76        rtas_setup_phb(phb);
  77        pci_process_bridge_OF_ranges(phb, dn, 0);
  78
  79        pci_devs_phb_init_dynamic(phb);
  80
  81        /* Create EEH devices for the PHB */
  82        eeh_dev_phb_init_dynamic(phb);
  83
  84        if (dn->child)
  85                eeh_add_device_tree_early(dn);
  86
  87        pcibios_scan_phb(phb);
  88        pcibios_finish_adding_to_bus(phb->bus);
  89
  90        return phb;
  91}
  92EXPORT_SYMBOL_GPL(init_phb_dynamic);
  93
  94/* RPA-specific bits for removing PHBs */
  95int remove_phb_dynamic(struct pci_controller *phb)
  96{
  97        struct pci_bus *b = phb->bus;
  98        struct resource *res;
  99        int rc, i;
 100
 101        pr_debug("PCI: Removing PHB %04x:%02x...\n",
 102                 pci_domain_nr(b), b->number);
 103
 104        /* We cannot to remove a root bus that has children */
 105        if (!(list_empty(&b->children) && list_empty(&b->devices)))
 106                return -EBUSY;
 107
 108        /* We -know- there aren't any child devices anymore at this stage
 109         * and thus, we can safely unmap the IO space as it's not in use
 110         */
 111        res = &phb->io_resource;
 112        if (res->flags & IORESOURCE_IO) {
 113                rc = pcibios_unmap_io_space(b);
 114                if (rc) {
 115                        printk(KERN_ERR "%s: failed to unmap IO on bus %s\n",
 116                               __func__, b->name);
 117                        return 1;
 118                }
 119        }
 120
 121        /* Unregister the bridge device from sysfs and remove the PCI bus */
 122        device_unregister(b->bridge);
 123        phb->bus = NULL;
 124        pci_remove_bus(b);
 125
 126        /* Now release the IO resource */
 127        if (res->flags & IORESOURCE_IO)
 128                release_resource(res);
 129
 130        /* Release memory resources */
 131        for (i = 0; i < 3; ++i) {
 132                res = &phb->mem_resources[i];
 133                if (!(res->flags & IORESOURCE_MEM))
 134                        continue;
 135                release_resource(res);
 136        }
 137
 138        /* Free pci_controller data structure */
 139        pcibios_free_controller(phb);
 140
 141        return 0;
 142}
 143EXPORT_SYMBOL_GPL(remove_phb_dynamic);
 144