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
  31 static struct pci_bus *
  32 find_bus_among_children(struct pci_bus *bus,
  33                         struct device_node *dn)
  34 {
  35         struct pci_bus *child = NULL;
  36         struct list_head *tmp;
  37         struct device_node *busdn;
  38
  39         busdn = pci_bus_to_OF_node(bus);
  40         if (busdn == dn)
  41                 return bus;
  42
  43         list_for_each(tmp, &bus->children) {
  44                 child = find_bus_among_children(pci_bus_b(tmp), dn);
  45                 if (child)
  46                         break;
  47         };
  48         return child;
  49 }
  50
  51 struct pci_bus *
  52 pcibios_find_pci_bus(struct device_node *dn)
  53 {
  54         struct pci_dn *pdn = dn->data;
  55
  56         if (!pdn  || !pdn->phb || !pdn->phb->bus)
  57                 return NULL;
  58
  59         return find_bus_among_children(pdn->phb->bus, dn);
  60 }
  61 EXPORT_SYMBOL_GPL(pcibios_find_pci_bus);
  62
  63 /**
  64  * pcibios_remove_pci_devices - remove all devices under this bus
  65  *
  66  * Remove all of the PCI devices under this bus both from the
  67  * linux pci device tree, and from the powerpc EEH address cache.
  68  */
  69 void
  70 pcibios_remove_pci_devices(struct pci_bus *bus)
  71 {
  72         struct pci_dev *dev, *tmp;
  73
  74         list_for_each_entry_safe(dev, tmp, &bus->devices, bus_list) {
  75                 eeh_remove_bus_device(dev);
  76                 pci_remove_bus_device(dev);
  77         }
  78 }
  79
  80 /* Must be called before pci_bus_add_devices */
  81 void
  82 pcibios_fixup_new_pci_devices(struct pci_bus *bus, int fix_bus)
  83 {
  84         struct pci_dev *dev;
  85
  86         list_for_each_entry(dev, &bus->devices, bus_list) {
  87                 /*
  88                  * Skip already-present devices (which are on the
  89                  * global device list.)
  90                  */
  91                 if (list_empty(&dev->global_list)) {
  92                         int i;
  93
  94                         /* Need to setup IOMMU tables */
  95                         ppc_md.iommu_dev_setup(dev);
  96
  97                         if(fix_bus)
  98                                 pcibios_fixup_device_resources(dev, bus);
  99                         pci_read_irq_line(dev);
 100                         for (i = 0; i < PCI_NUM_RESOURCES; i++) {
 101                                 struct resource *r = &dev->resource[i];
 102
 103                                 if (r->parent || !r->start || !r->flags)
 104                                         continue;
 105                                 pci_claim_resource(dev, i);
 106                         }
 107                 }
 108         }
 109
 110         eeh_add_device_tree_late(bus);
 111 }
 112 EXPORT_SYMBOL_GPL(pcibios_fixup_new_pci_devices);
 113
 114 static int
 115 pcibios_pci_config_bridge(struct pci_dev *dev)
 116 {
 117         u8 sec_busno;
 118         struct pci_bus *child_bus;
 119
 120         /* Get busno of downstream bus */
 121         pci_read_config_byte(dev, PCI_SECONDARY_BUS, &sec_busno);
 122
 123         /* Add to children of PCI bridge dev->bus */
 124         child_bus = pci_add_new_bus(dev->bus, dev, sec_busno);
 125         if (!child_bus) {
 126                 printk (KERN_ERR "%s: could not add second bus\n", __FUNCTION__);
 127                 return -EIO;
 128         }
 129         sprintf(child_bus->name, "PCI Bus #%02x", child_bus->number);
 130
 131         pci_scan_child_bus(child_bus);
 132
 133         /* Fixup new pci devices without touching bus struct */
 134         pcibios_fixup_new_pci_devices(child_bus, 0);
 135
 136         /* Make the discovered devices available */
 137         pci_bus_add_devices(child_bus);
 138         return 0;
 139 }
 140
 141 /**
 142  * pcibios_add_pci_devices - adds new pci devices to bus
 143  *
 144  * This routine will find and fixup new pci devices under
 145  * the indicated bus. This routine presumes that there
 146  * might already be some devices under this bridge, so
 147  * it carefully tries to add only new devices.  (And that
 148  * is how this routine differs from other, similar pcibios
 149  * routines.)
 150  */
 151 void
 152 pcibios_add_pci_devices(struct pci_bus * bus)
 153 {
 154         int slotno, num;
 155         struct pci_dev *dev;
 156         struct device_node *dn = pci_bus_to_OF_node(bus);
 157
 158         eeh_add_device_tree_early(dn);
 159
 160         if (_machine == PLATFORM_PSERIES_LPAR) {
 161                 /* use ofdt-based probe */
 162                 of_scan_bus(dn, bus);
 163                 if (!list_empty(&bus->devices)) {
 164                         pcibios_fixup_new_pci_devices(bus, 0);
 165                         pci_bus_add_devices(bus);
 166                 }
 167         } else {
 168                 /* use legacy probe */
 169                 slotno = PCI_SLOT(PCI_DN(dn->child)->devfn);
 170                 num = pci_scan_slot(bus, PCI_DEVFN(slotno, 0));
 171                 if (num) {
 172                         pcibios_fixup_new_pci_devices(bus, 1);
 173                         pci_bus_add_devices(bus);
 174                 }
 175
 176                 list_for_each_entry(dev, &bus->devices, bus_list)
 177                         if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE)
 178                                 pcibios_pci_config_bridge(dev);
 179         }
 180 }
 181 EXPORT_SYMBOL_GPL(pcibios_add_pci_devices);