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  * @bus: the indicated PCI bus
  70  * @purge_pe: destroy the PE on removal of PCI devices
  71  *
  72  * Remove all of the PCI devices under this bus both from the
  73  * linux pci device tree, and from the powerpc EEH address cache.
  74  * By default, the corresponding PE will be destroied during the
  75  * normal PCI hotplug path. For PCI hotplug during EEH recovery,
  76  * the corresponding PE won't be destroied and deallocated.
  77  */
  78 void __pcibios_remove_pci_devices(struct pci_bus *bus, int purge_pe)
  79 {
  80         struct pci_dev *dev, *tmp;
  81         struct pci_bus *child_bus;
  82
  83         /* First go down child busses */
  84         list_for_each_entry(child_bus, &bus->children, node)
  85                 __pcibios_remove_pci_devices(child_bus, purge_pe);
  86
  87         pr_debug("PCI: Removing devices on bus %04x:%02x\n",
  88                 pci_domain_nr(bus),  bus->number);
  89         list_for_each_entry_safe(dev, tmp, &bus->devices, bus_list) {
  90                 pr_debug("     * Removing %s...\n", pci_name(dev));
  91                 eeh_remove_bus_device(dev, purge_pe);
  92                 pci_stop_and_remove_bus_device(dev);
  93         }
  94 }
  95
  96 /**
  97  * pcibios_remove_pci_devices - remove all devices under this bus
  98  *
  99  * Remove all of the PCI devices under this bus both from the
 100  * linux pci device tree, and from the powerpc EEH address cache.
 101  */
 102 void pcibios_remove_pci_devices(struct pci_bus *bus)
 103 {
 104         __pcibios_remove_pci_devices(bus, 1);
 105 }
 106 EXPORT_SYMBOL_GPL(pcibios_remove_pci_devices);
 107
 108 /**
 109  * pcibios_add_pci_devices - adds new pci devices to bus
 110  *
 111  * This routine will find and fixup new pci devices under
 112  * the indicated bus. This routine presumes that there
 113  * might already be some devices under this bridge, so
 114  * it carefully tries to add only new devices.  (And that
 115  * is how this routine differs from other, similar pcibios
 116  * routines.)
 117  */
 118 void pcibios_add_pci_devices(struct pci_bus * bus)
 119 {
 120         int slotno, num, mode, pass, max;
 121         struct pci_dev *dev;
 122         struct device_node *dn = pci_bus_to_OF_node(bus);
 123
 124         eeh_add_device_tree_early(dn);
 125
 126         mode = PCI_PROBE_NORMAL;
 127         if (ppc_md.pci_probe_mode)
 128                 mode = ppc_md.pci_probe_mode(bus);
 129
 130         if (mode == PCI_PROBE_DEVTREE) {
 131                 /* use ofdt-based probe */
 132                 of_rescan_bus(dn, bus);
 133         } else if (mode == PCI_PROBE_NORMAL) {
 134                 /* use legacy probe */
 135                 slotno = PCI_SLOT(PCI_DN(dn->child)->devfn);
 136                 num = pci_scan_slot(bus, PCI_DEVFN(slotno, 0));
 137                 if (!num)
 138                         return;
 139                 pcibios_setup_bus_devices(bus);
 140                 max = bus->busn_res.start;
 141                 for (pass=0; pass < 2; pass++)
 142                         list_for_each_entry(dev, &bus->devices, bus_list) {
 143                         if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE ||
 144                             dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)
 145                                 max = pci_scan_bridge(bus, dev, max, pass);
 146                 }
 147         }
 148         pcibios_finish_adding_to_bus(bus);
 149 }
 150 EXPORT_SYMBOL_GPL(pcibios_add_pci_devices);
 151
 152 struct pci_controller *init_phb_dynamic(struct device_node *dn)
 153 {
 154         struct pci_controller *phb;
 155
 156         pr_debug("PCI: Initializing new hotplug PHB %s\n", dn->full_name);
 157
 158         phb = pcibios_alloc_controller(dn);
 159         if (!phb)
 160                 return NULL;
 161         rtas_setup_phb(phb);
 162         pci_process_bridge_OF_ranges(phb, dn, 0);
 163
 164         pci_devs_phb_init_dynamic(phb);
 165
 166         /* Create EEH devices for the PHB */
 167         eeh_dev_phb_init_dynamic(phb);
 168
 169         if (dn->child)
 170                 eeh_add_device_tree_early(dn);
 171
 172         pcibios_scan_phb(phb);
 173         pcibios_finish_adding_to_bus(phb->bus);
 174
 175         return phb;
 176 }
 177 EXPORT_SYMBOL_GPL(init_phb_dynamic);
 178
 179 /* RPA-specific bits for removing PHBs */
 180 int remove_phb_dynamic(struct pci_controller *phb)
 181 {
 182         struct pci_bus *b = phb->bus;
 183         struct resource *res;
 184         int rc, i;
 185
 186         pr_debug("PCI: Removing PHB %04x:%02x...\n",
 187                  pci_domain_nr(b), b->number);
 188
 189         /* We cannot to remove a root bus that has children */
 190         if (!(list_empty(&b->children) && list_empty(&b->devices)))
 191                 return -EBUSY;
 192
 193         /* We -know- there aren't any child devices anymore at this stage
 194          * and thus, we can safely unmap the IO space as it's not in use
 195          */
 196         res = &phb->io_resource;
 197         if (res->flags & IORESOURCE_IO) {
 198                 rc = pcibios_unmap_io_space(b);
 199                 if (rc) {
 200                         printk(KERN_ERR "%s: failed to unmap IO on bus %s\n",
 201                                __func__, b->name);
 202                         return 1;
 203                 }
 204         }
 205
 206         /* Unregister the bridge device from sysfs and remove the PCI bus */
 207         device_unregister(b->bridge);
 208         phb->bus = NULL;
 209         pci_remove_bus(b);
 210
 211         /* Now release the IO resource */
 212         if (res->flags & IORESOURCE_IO)
 213                 release_resource(res);
 214
 215         /* Release memory resources */
 216         for (i = 0; i < 3; ++i) {
 217                 res = &phb->mem_resources[i];
 218                 if (!(res->flags & IORESOURCE_MEM))
 219                         continue;
 220                 release_resource(res);
 221         }
 222
 223         /* Free pci_controller data structure */
 224         pcibios_free_controller(phb);
 225
 226         return 0;
 227 }
 228 EXPORT_SYMBOL_GPL(remove_phb_dynamic);