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 #undef DEBUG
  29
  30 #include <linux/pci.h>
  31 #include <asm/pci-bridge.h>
  32 #include <asm/ppc-pci.h>
  33 #include <asm/firmware.h>
  34 #include <asm/eeh.h>
  35
  36 static struct pci_bus *
  37 find_bus_among_children(struct pci_bus *bus,
  38                         struct device_node *dn)
  39 {
  40         struct pci_bus *child = NULL;
  41         struct list_head *tmp;
  42         struct device_node *busdn;
  43
  44         busdn = pci_bus_to_OF_node(bus);
  45         if (busdn == dn)
  46                 return bus;
  47
  48         list_for_each(tmp, &bus->children) {
  49                 child = find_bus_among_children(pci_bus_b(tmp), dn);
  50                 if (child)
  51                         break;
  52         };
  53         return child;
  54 }
  55
  56 struct pci_bus *
  57 pcibios_find_pci_bus(struct device_node *dn)
  58 {
  59         struct pci_dn *pdn = dn->data;
  60
  61         if (!pdn  || !pdn->phb || !pdn->phb->bus)
  62                 return NULL;
  63
  64         return find_bus_among_children(pdn->phb->bus, dn);
  65 }
  66 EXPORT_SYMBOL_GPL(pcibios_find_pci_bus);
  67
  68 /**
  69  * pcibios_remove_pci_devices - remove all devices under this bus
  70  *
  71  * Remove all of the PCI devices under this bus both from the
  72  * linux pci device tree, and from the powerpc EEH address cache.
  73  */
  74 void pcibios_remove_pci_devices(struct pci_bus *bus)
  75 {
  76         struct pci_dev *dev, *tmp;
  77         struct pci_bus *child_bus;
  78
  79         /* First go down child busses */
  80         list_for_each_entry(child_bus, &bus->children, node)
  81                 pcibios_remove_pci_devices(child_bus);
  82
  83         pr_debug("PCI: Removing devices on bus %04x:%02x\n",
  84                  pci_domain_nr(bus),  bus->number);
  85         list_for_each_entry_safe(dev, tmp, &bus->devices, bus_list) {
  86                 pr_debug("     * Removing %s...\n", pci_name(dev));
  87                 eeh_remove_bus_device(dev);
  88                 pci_remove_bus_device(dev);
  89         }
  90 }
  91 EXPORT_SYMBOL_GPL(pcibios_remove_pci_devices);
  92
  93 /**
  94  * pcibios_add_pci_devices - adds new pci devices to bus
  95  *
  96  * This routine will find and fixup new pci devices under
  97  * the indicated bus. This routine presumes that there
  98  * might already be some devices under this bridge, so
  99  * it carefully tries to add only new devices.  (And that
 100  * is how this routine differs from other, similar pcibios
 101  * routines.)
 102  */
 103 void pcibios_add_pci_devices(struct pci_bus * bus)
 104 {
 105         int slotno, num, mode, pass, max;
 106         struct pci_dev *dev;
 107         struct device_node *dn = pci_bus_to_OF_node(bus);
 108
 109         eeh_add_device_tree_early(dn);
 110
 111         mode = PCI_PROBE_NORMAL;
 112         if (ppc_md.pci_probe_mode)
 113                 mode = ppc_md.pci_probe_mode(bus);
 114
 115         if (mode == PCI_PROBE_DEVTREE) {
 116                 /* use ofdt-based probe */
 117                 of_rescan_bus(dn, bus);
 118         } else if (mode == PCI_PROBE_NORMAL) {
 119                 /* use legacy probe */
 120                 slotno = PCI_SLOT(PCI_DN(dn->child)->devfn);
 121                 num = pci_scan_slot(bus, PCI_DEVFN(slotno, 0));
 122                 if (!num)
 123                         return;
 124                 pcibios_setup_bus_devices(bus);
 125                 max = bus->secondary;
 126                 for (pass=0; pass < 2; pass++)
 127                         list_for_each_entry(dev, &bus->devices, bus_list) {
 128                         if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE ||
 129                             dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)
 130                                 max = pci_scan_bridge(bus, dev, max, pass);
 131                 }
 132         }
 133         pcibios_finish_adding_to_bus(bus);
 134 }
 135 EXPORT_SYMBOL_GPL(pcibios_add_pci_devices);
 136
 137 struct pci_controller * __devinit init_phb_dynamic(struct device_node *dn)
 138 {
 139         struct pci_controller *phb;
 140
 141         pr_debug("PCI: Initializing new hotplug PHB %s\n", dn->full_name);
 142
 143         phb = pcibios_alloc_controller(dn);
 144         if (!phb)
 145                 return NULL;
 146         rtas_setup_phb(phb);
 147         pci_process_bridge_OF_ranges(phb, dn, 0);
 148
 149         pci_devs_phb_init_dynamic(phb);
 150
 151         if (dn->child)
 152                 eeh_add_device_tree_early(dn);
 153
 154         pcibios_scan_phb(phb, dn);
 155         pcibios_finish_adding_to_bus(phb->bus);
 156
 157         return phb;
 158 }
 159 EXPORT_SYMBOL_GPL(init_phb_dynamic);
 160
 161 /* RPA-specific bits for removing PHBs */
 162 int remove_phb_dynamic(struct pci_controller *phb)
 163 {
 164         struct pci_bus *b = phb->bus;
 165         struct resource *res;
 166         int rc, i;
 167
 168         pr_debug("PCI: Removing PHB %04x:%02x... \n",
 169                  pci_domain_nr(b), b->number);
 170
 171         /* We cannot to remove a root bus that has children */
 172         if (!(list_empty(&b->children) && list_empty(&b->devices)))
 173                 return -EBUSY;
 174
 175         /* We -know- there aren't any child devices anymore at this stage
 176          * and thus, we can safely unmap the IO space as it's not in use
 177          */
 178         res = &phb->io_resource;
 179         if (res->flags & IORESOURCE_IO) {
 180                 rc = pcibios_unmap_io_space(b);
 181                 if (rc) {
 182                         printk(KERN_ERR "%s: failed to unmap IO on bus %s\n",
 183                                __func__, b->name);
 184                         return 1;
 185                 }
 186         }
 187
 188         /* Unregister the bridge device from sysfs and remove the PCI bus */
 189         device_unregister(b->bridge);
 190         phb->bus = NULL;
 191         pci_remove_bus(b);
 192
 193         /* Now release the IO resource */
 194         if (res->flags & IORESOURCE_IO)
 195                 release_resource(res);
 196
 197         /* Release memory resources */
 198         for (i = 0; i < 3; ++i) {
 199                 res = &phb->mem_resources[i];
 200                 if (!(res->flags & IORESOURCE_MEM))
 201                         continue;
 202                 release_resource(res);
 203         }
 204
 205         /* Free pci_controller data structure */
 206         pcibios_free_controller(phb);
 207
 208         return 0;
 209 }
 210 EXPORT_SYMBOL_GPL(remove_phb_dynamic);