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 static struct pci_bus *
  36 find_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
  55 struct pci_bus *
  56 pcibios_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 }
  65 EXPORT_SYMBOL_GPL(pcibios_find_pci_bus);
  66
  67 /**
  68  * pcibios_remove_pci_devices - remove all devices under this bus
  69  *
  70  * Remove all of the PCI devices under this bus both from the
  71  * linux pci device tree, and from the powerpc EEH address cache.
  72  */
  73 void pcibios_remove_pci_devices(struct pci_bus *bus)
  74 {
  75         struct pci_dev *dev, *tmp;
  76         struct pci_bus *child_bus;
  77
  78         /* First go down child busses */
  79         list_for_each_entry(child_bus, &bus->children, node)
  80                 pcibios_remove_pci_devices(child_bus);
  81
  82         pr_debug("PCI: Removing devices on bus %04x:%02x\n",
  83                  pci_domain_nr(bus),  bus->number);
  84         list_for_each_entry_safe(dev, tmp, &bus->devices, bus_list) {
  85                 pr_debug("     * Removing %s...\n", pci_name(dev));
  86                 eeh_remove_bus_device(dev);
  87                 pci_remove_bus_device(dev);
  88         }
  89 }
  90 EXPORT_SYMBOL_GPL(pcibios_remove_pci_devices);
  91
  92 /**
  93  * pcibios_add_pci_devices - adds new pci devices to bus
  94  *
  95  * This routine will find and fixup new pci devices under
  96  * the indicated bus. This routine presumes that there
  97  * might already be some devices under this bridge, so
  98  * it carefully tries to add only new devices.  (And that
  99  * is how this routine differs from other, similar pcibios
 100  * routines.)
 101  */
 102 void pcibios_add_pci_devices(struct pci_bus * bus)
 103 {
 104         int slotno, num, mode, pass, max;
 105         struct pci_dev *dev;
 106         struct device_node *dn = pci_bus_to_OF_node(bus);
 107
 108         eeh_add_device_tree_early(dn);
 109
 110         mode = PCI_PROBE_NORMAL;
 111         if (ppc_md.pci_probe_mode)
 112                 mode = ppc_md.pci_probe_mode(bus);
 113
 114         if (mode == PCI_PROBE_DEVTREE) {
 115                 /* use ofdt-based probe */
 116                 of_rescan_bus(dn, bus);
 117         } else if (mode == PCI_PROBE_NORMAL) {
 118                 /* use legacy probe */
 119                 slotno = PCI_SLOT(PCI_DN(dn->child)->devfn);
 120                 num = pci_scan_slot(bus, PCI_DEVFN(slotno, 0));
 121                 if (!num)
 122                         return;
 123                 pcibios_setup_bus_devices(bus);
 124                 max = bus->secondary;
 125                 for (pass=0; pass < 2; pass++)
 126                         list_for_each_entry(dev, &bus->devices, bus_list) {
 127                         if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE ||
 128                             dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)
 129                                 max = pci_scan_bridge(bus, dev, max, pass);
 130                 }
 131         }
 132         pcibios_finish_adding_to_bus(bus);
 133 }
 134 EXPORT_SYMBOL_GPL(pcibios_add_pci_devices);
 135
 136 struct pci_controller * __devinit init_phb_dynamic(struct device_node *dn)
 137 {
 138         struct pci_controller *phb;
 139
 140         pr_debug("PCI: Initializing new hotplug PHB %s\n", dn->full_name);
 141
 142         phb = pcibios_alloc_controller(dn);
 143         if (!phb)
 144                 return NULL;
 145         rtas_setup_phb(phb);
 146         pci_process_bridge_OF_ranges(phb, dn, 0);
 147
 148         pci_devs_phb_init_dynamic(phb);
 149
 150         if (dn->child)
 151                 eeh_add_device_tree_early(dn);
 152
 153         pcibios_scan_phb(phb);
 154         pcibios_finish_adding_to_bus(phb->bus);
 155
 156         return phb;
 157 }
 158 EXPORT_SYMBOL_GPL(init_phb_dynamic);
 159
 160 /* RPA-specific bits for removing PHBs */
 161 int remove_phb_dynamic(struct pci_controller *phb)
 162 {
 163         struct pci_bus *b = phb->bus;
 164         struct resource *res;
 165         int rc, i;
 166
 167         pr_debug("PCI: Removing PHB %04x:%02x...\n",
 168                  pci_domain_nr(b), b->number);
 169
 170         /* We cannot to remove a root bus that has children */
 171         if (!(list_empty(&b->children) && list_empty(&b->devices)))
 172                 return -EBUSY;
 173
 174         /* We -know- there aren't any child devices anymore at this stage
 175          * and thus, we can safely unmap the IO space as it's not in use
 176          */
 177         res = &phb->io_resource;
 178         if (res->flags & IORESOURCE_IO) {
 179                 rc = pcibios_unmap_io_space(b);
 180                 if (rc) {
 181                         printk(KERN_ERR "%s: failed to unmap IO on bus %s\n",
 182                                __func__, b->name);
 183                         return 1;
 184                 }
 185         }
 186
 187         /* Unregister the bridge device from sysfs and remove the PCI bus */
 188         device_unregister(b->bridge);
 189         phb->bus = NULL;
 190         pci_remove_bus(b);
 191
 192         /* Now release the IO resource */
 193         if (res->flags & IORESOURCE_IO)
 194                 release_resource(res);
 195
 196         /* Release memory resources */
 197         for (i = 0; i < 3; ++i) {
 198                 res = &phb->mem_resources[i];
 199                 if (!(res->flags & IORESOURCE_MEM))
 200                         continue;
 201                 release_resource(res);
 202         }
 203
 204         /* Free pci_controller data structure */
 205         pcibios_free_controller(phb);
 206
 207         return 0;
 208 }
 209 EXPORT_SYMBOL_GPL(remove_phb_dynamic);