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 <linux/pci-acpi.h>
  23 #include <xen/xen.h>
  24 #include <xen/interface/physdev.h>
  25 #include <xen/interface/xen.h>
  26
  27 #include <asm/xen/hypervisor.h>
  28 #include <asm/xen/hypercall.h>
  29 #include "../pci/pci.h"
  30 #ifdef CONFIG_PCI_MMCONFIG
  31 #include <asm/pci_x86.h>
  32 #endif
  33
  34 static bool __read_mostly pci_seg_supported = true;
  35
  36 static int xen_add_device(struct device *dev)
  37 {
  38         int r;
  39         struct pci_dev *pci_dev = to_pci_dev(dev);
  40 #ifdef CONFIG_PCI_IOV
  41         struct pci_dev *physfn = pci_dev->physfn;
  42 #endif
  43
  44         if (pci_seg_supported) {
  45                 struct {
  46                         struct physdev_pci_device_add add;
  47                         uint32_t pxm;
  48                 } add_ext = {
  49                         .add.seg = pci_domain_nr(pci_dev->bus),
  50                         .add.bus = pci_dev->bus->number,
  51                         .add.devfn = pci_dev->devfn
  52                 };
  53                 struct physdev_pci_device_add *add = &add_ext.add;
  54
  55 #ifdef CONFIG_ACPI
  56                 acpi_handle handle;
  57 #endif
  58
  59 #ifdef CONFIG_PCI_IOV
  60                 if (pci_dev->is_virtfn) {
  61                         add->flags = XEN_PCI_DEV_VIRTFN;
  62                         add->physfn.bus = physfn->bus->number;
  63                         add->physfn.devfn = physfn->devfn;
  64                 } else
  65 #endif
  66                 if (pci_ari_enabled(pci_dev->bus) && PCI_SLOT(pci_dev->devfn))
  67                         add->flags = XEN_PCI_DEV_EXTFN;
  68
  69 #ifdef CONFIG_ACPI
  70                 handle = ACPI_HANDLE(&pci_dev->dev);
  71 #ifdef CONFIG_PCI_IOV
  72                 if (!handle && pci_dev->is_virtfn)
  73                         handle = ACPI_HANDLE(physfn->bus->bridge);
  74 #endif
  75                 if (!handle) {
  76                         /*
  77                          * This device was not listed in the ACPI name space at
  78                          * all. Try to get acpi handle of parent pci bus.
  79                          */
  80                         struct pci_bus *pbus;
  81                         for (pbus = pci_dev->bus; pbus; pbus = pbus->parent) {
  82                                 handle = acpi_pci_get_bridge_handle(pbus);
  83                                 if (handle)
  84                                         break;
  85                         }
  86                 }
  87                 if (handle) {
  88                         acpi_status status;
  89
  90                         do {
  91                                 unsigned long long pxm;
  92
  93                                 status = acpi_evaluate_integer(handle, "_PXM",
  94                                                                NULL, &pxm);
  95                                 if (ACPI_SUCCESS(status)) {
  96                                         add->optarr[0] = pxm;
  97                                         add->flags |= XEN_PCI_DEV_PXM;
  98                                         break;
  99                                 }
 100                                 status = acpi_get_parent(handle, &handle);
 101                         } while (ACPI_SUCCESS(status));
 102                 }
 103 #endif /* CONFIG_ACPI */
 104
 105                 r = HYPERVISOR_physdev_op(PHYSDEVOP_pci_device_add, add);
 106                 if (r != -ENOSYS)
 107                         return r;
 108                 pci_seg_supported = false;
 109         }
 110
 111         if (pci_domain_nr(pci_dev->bus))
 112                 r = -ENOSYS;
 113 #ifdef CONFIG_PCI_IOV
 114         else if (pci_dev->is_virtfn) {
 115                 struct physdev_manage_pci_ext manage_pci_ext = {
 116                         .bus            = pci_dev->bus->number,
 117                         .devfn          = pci_dev->devfn,
 118                         .is_virtfn      = 1,
 119                         .physfn.bus     = physfn->bus->number,
 120                         .physfn.devfn   = physfn->devfn,
 121                 };
 122
 123                 r = HYPERVISOR_physdev_op(PHYSDEVOP_manage_pci_add_ext,
 124                         &manage_pci_ext);
 125         }
 126 #endif
 127         else if (pci_ari_enabled(pci_dev->bus) && PCI_SLOT(pci_dev->devfn)) {
 128                 struct physdev_manage_pci_ext manage_pci_ext = {
 129                         .bus            = pci_dev->bus->number,
 130                         .devfn          = pci_dev->devfn,
 131                         .is_extfn       = 1,
 132                 };
 133
 134                 r = HYPERVISOR_physdev_op(PHYSDEVOP_manage_pci_add_ext,
 135                         &manage_pci_ext);
 136         } else {
 137                 struct physdev_manage_pci manage_pci = {
 138                         .bus    = pci_dev->bus->number,
 139                         .devfn  = pci_dev->devfn,
 140                 };
 141
 142                 r = HYPERVISOR_physdev_op(PHYSDEVOP_manage_pci_add,
 143                         &manage_pci);
 144         }
 145
 146         return r;
 147 }
 148
 149 static int xen_remove_device(struct device *dev)
 150 {
 151         int r;
 152         struct pci_dev *pci_dev = to_pci_dev(dev);
 153
 154         if (pci_seg_supported) {
 155                 struct physdev_pci_device device = {
 156                         .seg = pci_domain_nr(pci_dev->bus),
 157                         .bus = pci_dev->bus->number,
 158                         .devfn = pci_dev->devfn
 159                 };
 160
 161                 r = HYPERVISOR_physdev_op(PHYSDEVOP_pci_device_remove,
 162                                           &device);
 163         } else if (pci_domain_nr(pci_dev->bus))
 164                 r = -ENOSYS;
 165         else {
 166                 struct physdev_manage_pci manage_pci = {
 167                         .bus = pci_dev->bus->number,
 168                         .devfn = pci_dev->devfn
 169                 };
 170
 171                 r = HYPERVISOR_physdev_op(PHYSDEVOP_manage_pci_remove,
 172                                           &manage_pci);
 173         }
 174
 175         return r;
 176 }
 177
 178 static int xen_pci_notifier(struct notifier_block *nb,
 179                             unsigned long action, void *data)
 180 {
 181         struct device *dev = data;
 182         int r = 0;
 183
 184         switch (action) {
 185         case BUS_NOTIFY_ADD_DEVICE:
 186                 r = xen_add_device(dev);
 187                 break;
 188         case BUS_NOTIFY_DEL_DEVICE:
 189                 r = xen_remove_device(dev);
 190                 break;
 191         default:
 192                 return NOTIFY_DONE;
 193         }
 194         if (r)
 195                 dev_err(dev, "Failed to %s - passthrough or MSI/MSI-X might fail!\n",
 196                         action == BUS_NOTIFY_ADD_DEVICE ? "add" :
 197                         (action == BUS_NOTIFY_DEL_DEVICE ? "delete" : "?"));
 198         return NOTIFY_OK;
 199 }
 200
 201 static struct notifier_block device_nb = {
 202         .notifier_call = xen_pci_notifier,
 203 };
 204
 205 static int __init register_xen_pci_notifier(void)
 206 {
 207         if (!xen_initial_domain())
 208                 return 0;
 209
 210         return bus_register_notifier(&pci_bus_type, &device_nb);
 211 }
 212
 213 arch_initcall(register_xen_pci_notifier);
 214
 215 #ifdef CONFIG_PCI_MMCONFIG
 216 static int __init xen_mcfg_late(void)
 217 {
 218         struct pci_mmcfg_region *cfg;
 219         int rc;
 220
 221         if (!xen_initial_domain())
 222                 return 0;
 223
 224         if ((pci_probe & PCI_PROBE_MMCONF) == 0)
 225                 return 0;
 226
 227         if (list_empty(&pci_mmcfg_list))
 228                 return 0;
 229
 230         /* Check whether they are in the right area. */
 231         list_for_each_entry(cfg, &pci_mmcfg_list, list) {
 232                 struct physdev_pci_mmcfg_reserved r;
 233
 234                 r.address = cfg->address;
 235                 r.segment = cfg->segment;
 236                 r.start_bus = cfg->start_bus;
 237                 r.end_bus = cfg->end_bus;
 238                 r.flags = XEN_PCI_MMCFG_RESERVED;
 239
 240                 rc = HYPERVISOR_physdev_op(PHYSDEVOP_pci_mmcfg_reserved, &r);
 241                 switch (rc) {
 242                 case 0:
 243                 case -ENOSYS:
 244                         continue;
 245
 246                 default:
 247                         pr_warn("Failed to report MMCONFIG reservation"
 248                                 " state for %s to hypervisor"
 249                                 " (%d)\n",
 250                                 cfg->name, rc);
 251                 }
 252         }
 253         return 0;
 254 }
 255 /*
 256  * Needs to be done after acpi_init which are subsys_initcall.
 257  */
 258 subsys_initcall_sync(xen_mcfg_late);
 259 #endif