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