arch/powerpc/platforms/pseries/pci_dlpar.c

   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
  37 static struct pci_bus *
  38 find_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
  57 struct pci_bus *
  58 pcibios_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 }
  67 EXPORT_SYMBOL_GPL(pcibios_find_pci_bus);
  68
  69 struct 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 }
  95 EXPORT_SYMBOL_GPL(init_phb_dynamic);
  96
  97 /* RPA-specific bits for removing PHBs */
  98 int 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         /* Free pci_controller data structure */
 142         pcibios_free_controller(phb);
 143
 144         return 0;
 145 }
 146 EXPORT_SYMBOL_GPL(remove_phb_dynamic);