drivers/xen/pci.c

   1 /*
   2  * Copyright (c) 2009, Intel Corporation.
   3  *
   4  * This program is free software; you can redistribute it and/or modify it
   5  * under the terms and conditions of the GNU General Public License,
   6  * version 2, as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope it will be useful, but WITHOUT
   9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  11  * more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along with
  14  * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
  15  * Place - Suite 330, Boston, MA 02111-1307 USA.
  16  *
  17  * Author: Weidong Han <weidong.han@intel.com>
  18  */
  19
  20 #include <linux/pci.h>
  21 #include <linux/acpi.h>
  22 #include <xen/xen.h>
  23 #include <xen/interface/physdev.h>
  24 #include <xen/interface/xen.h>
  25
  26 #include <asm/xen/hypervisor.h>
  27 #include <asm/xen/hypercall.h>
  28 #include "../pci/pci.h"
  29 #ifdef CONFIG_PCI_MMCONFIG
  30 #include <asm/pci_x86.h>
  31 #endif
  32
  33 static bool __read_mostly pci_seg_supported = true;
  34
  35 static int xen_add_device(struct device *dev)
  36 {
  37         int r;
  38         struct pci_dev *pci_dev = to_pci_dev(dev);
  39 #ifdef CONFIG_PCI_IOV
  40         struct pci_dev *physfn = pci_dev->physfn;
  41 #endif
  42
  43         if (pci_seg_supported) {
  44                 struct {
  45                         struct physdev_pci_device_add add;
  46                         uint32_t pxm;
  47                 } add_ext = {
  48                         .add.seg = pci_domain_nr(pci_dev->bus),
  49                         .add.bus = pci_dev->bus->number,
  50                         .add.devfn = pci_dev->devfn
  51                 };
  52                 struct physdev_pci_device_add *add = &add_ext.add;
  53
  54 #ifdef CONFIG_ACPI
  55                 acpi_handle handle;
  56 #endif
  57
  58 #ifdef CONFIG_PCI_IOV
  59                 if (pci_dev->is_virtfn) {
  60                         add->flags = XEN_PCI_DEV_VIRTFN;
  61                         add->physfn.bus = physfn->bus->number;
  62                         add->physfn.devfn = physfn->devfn;
  63                 } else
  64 #endif
  65                 if (pci_ari_enabled(pci_dev->bus) && PCI_SLOT(pci_dev->devfn))
  66                         add->flags = XEN_PCI_DEV_EXTFN;
  67
  68 #ifdef CONFIG_ACPI
  69                 handle = ACPI_HANDLE(&pci_dev->dev);
  70                 if (!handle && pci_dev->bus->bridge)
  71                         handle = ACPI_HANDLE(pci_dev->bus->bridge);
  72 #ifdef CONFIG_PCI_IOV
  73                 if (!handle && pci_dev->is_virtfn)
  74                         handle = ACPI_HANDLE(physfn->bus->bridge);
  75 #endif
  76                 if (handle) {
  77                         acpi_status status;
  78
  79                         do {
  80                                 unsigned long long pxm;
  81
  82                                 status = acpi_evaluate_integer(handle, "_PXM",
  83                                                                NULL, &pxm);
  84                                 if (ACPI_SUCCESS(status)) {
  85                                         add->optarr[0] = pxm;
  86                                         add->flags |= XEN_PCI_DEV_PXM;
  87                                         break;
  88                                 }
  89                                 status = acpi_get_parent(handle, &handle);
  90                         } while (ACPI_SUCCESS(status));
  91                 }
  92 #endif /* CONFIG_ACPI */
  93
  94                 r = HYPERVISOR_physdev_op(PHYSDEVOP_pci_device_add, add);
  95                 if (r != -ENOSYS)
  96                         return r;
  97                 pci_seg_supported = false;
  98         }
  99
 100         if (pci_domain_nr(pci_dev->bus))
 101                 r = -ENOSYS;
 102 #ifdef CONFIG_PCI_IOV
 103         else if (pci_dev->is_virtfn) {
 104                 struct physdev_manage_pci_ext manage_pci_ext = {
 105                         .bus            = pci_dev->bus->number,
 106                         .devfn          = pci_dev->devfn,
 107                         .is_virtfn      = 1,
 108                         .physfn.bus     = physfn->bus->number,
 109                         .physfn.devfn   = physfn->devfn,
 110                 };
 111
 112                 r = HYPERVISOR_physdev_op(PHYSDEVOP_manage_pci_add_ext,
 113                         &manage_pci_ext);
 114         }
 115 #endif
 116         else if (pci_ari_enabled(pci_dev->bus) && PCI_SLOT(pci_dev->devfn)) {
 117                 struct physdev_manage_pci_ext manage_pci_ext = {
 118                         .bus            = pci_dev->bus->number,
 119                         .devfn          = pci_dev->devfn,
 120                         .is_extfn       = 1,
 121                 };
 122
 123                 r = HYPERVISOR_physdev_op(PHYSDEVOP_manage_pci_add_ext,
 124                         &manage_pci_ext);
 125         } else {
 126                 struct physdev_manage_pci manage_pci = {
 127                         .bus    = pci_dev->bus->number,
 128                         .devfn  = pci_dev->devfn,
 129                 };
 130
 131                 r = HYPERVISOR_physdev_op(PHYSDEVOP_manage_pci_add,
 132                         &manage_pci);
 133         }
 134
 135         return r;
 136 }
 137
 138 static int xen_remove_device(struct device *dev)
 139 {
 140         int r;
 141         struct pci_dev *pci_dev = to_pci_dev(dev);
 142
 143         if (pci_seg_supported) {
 144                 struct physdev_pci_device device = {
 145                         .seg = pci_domain_nr(pci_dev->bus),
 146                         .bus = pci_dev->bus->number,
 147                         .devfn = pci_dev->devfn
 148                 };
 149
 150                 r = HYPERVISOR_physdev_op(PHYSDEVOP_pci_device_remove,
 151                                           &device);
 152         } else if (pci_domain_nr(pci_dev->bus))
 153                 r = -ENOSYS;
 154         else {
 155                 struct physdev_manage_pci manage_pci = {
 156                         .bus = pci_dev->bus->number,
 157                         .devfn = pci_dev->devfn
 158                 };
 159
 160                 r = HYPERVISOR_physdev_op(PHYSDEVOP_manage_pci_remove,
 161                                           &manage_pci);
 162         }
 163
 164         return r;
 165 }
 166
 167 static int xen_pci_notifier(struct notifier_block *nb,
 168                             unsigned long action, void *data)
 169 {
 170         struct device *dev = data;
 171         int r = 0;
 172
 173         switch (action) {
 174         case BUS_NOTIFY_ADD_DEVICE:
 175                 r = xen_add_device(dev);
 176                 break;
 177         case BUS_NOTIFY_DEL_DEVICE:
 178                 r = xen_remove_device(dev);
 179                 break;
 180         default:
 181                 return NOTIFY_DONE;
 182         }
 183         if (r)
 184                 dev_err(dev, "Failed to %s - passthrough or MSI/MSI-X might fail!\n",
 185                         action == BUS_NOTIFY_ADD_DEVICE ? "add" :
 186                         (action == BUS_NOTIFY_DEL_DEVICE ? "delete" : "?"));
 187         return NOTIFY_OK;
 188 }
 189
 190 static struct notifier_block device_nb = {
 191         .notifier_call = xen_pci_notifier,
 192 };
 193
 194 static int __init register_xen_pci_notifier(void)
 195 {
 196         if (!xen_initial_domain())
 197                 return 0;
 198
 199         return bus_register_notifier(&pci_bus_type, &device_nb);
 200 }
 201
 202 arch_initcall(register_xen_pci_notifier);
 203
 204 #ifdef CONFIG_PCI_MMCONFIG
 205 static int __init xen_mcfg_late(void)
 206 {
 207         struct pci_mmcfg_region *cfg;
 208         int rc;
 209
 210         if (!xen_initial_domain())
 211                 return 0;
 212
 213         if ((pci_probe & PCI_PROBE_MMCONF) == 0)
 214                 return 0;
 215
 216         if (list_empty(&pci_mmcfg_list))
 217                 return 0;
 218
 219         /* Check whether they are in the right area. */
 220         list_for_each_entry(cfg, &pci_mmcfg_list, list) {
 221                 struct physdev_pci_mmcfg_reserved r;
 222
 223                 r.address = cfg->address;
 224                 r.segment = cfg->segment;
 225                 r.start_bus = cfg->start_bus;
 226                 r.end_bus = cfg->end_bus;
 227                 r.flags = XEN_PCI_MMCFG_RESERVED;
 228
 229                 rc = HYPERVISOR_physdev_op(PHYSDEVOP_pci_mmcfg_reserved, &r);
 230                 switch (rc) {
 231                 case 0:
 232                 case -ENOSYS:
 233                         continue;
 234
 235                 default:
 236                         pr_warn("Failed to report MMCONFIG reservation"
 237                                 " state for %s to hypervisor"
 238                                 " (%d)\n",
 239                                 cfg->name, rc);
 240                 }
 241         }
 242         return 0;
 243 }
 244 /*
 245  * Needs to be done after acpi_init which are subsys_initcall.
 246  */
 247 subsys_initcall_sync(xen_mcfg_late);
 248 #endif