OvmfPkg/VirtioGpuDxe/DriverBinding.c

   1 /** @file
   2
   3   Implement the Driver Binding Protocol and the Component Name 2 Protocol for
   4   the Virtio GPU hybrid driver.
   5
   6   Copyright (C) 2016, Red Hat, Inc.
   7
   8   This program and the accompanying materials are licensed and made available
   9   under the terms and conditions of the BSD License which accompanies this
  10   distribution. The full text of the license may be found at
  11   http://opensource.org/licenses/bsd-license.php
  12
  13   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, WITHOUT
  14   WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  15
  16 **/
  17
  18 #include <Library/BaseMemoryLib.h>
  19 #include <Library/DevicePathLib.h>
  20 #include <Library/MemoryAllocationLib.h>
  21 #include <Library/PrintLib.h>
  22 #include <Library/UefiBootServicesTableLib.h>
  23 #include <Library/UefiLib.h>
  24 #include <Protocol/ComponentName2.h>
  25 #include <Protocol/DevicePath.h>
  26 #include <Protocol/DriverBinding.h>
  27 #include <Protocol/PciIo.h>
  28
  29 #include "VirtioGpu.h"
  30
  31 //
  32 // Dummy Graphics Output Protocol GUID: a temporary placeholder for the EFI
  33 // counterpart. It will be replaced with the real thing as soon as we implement
  34 // the EFI GOP. Refer to VGPU_GOP.Gop.
  35 //
  36 STATIC EFI_GUID mDummyGraphicsOutputProtocolGuid = {
  37   0x4983f8dc, 0x2782, 0x415b,
  38   { 0x91, 0xf5, 0x2c, 0xeb, 0x48, 0x4a, 0x0f, 0xe9 }
  39 };
  40
  41 //
  42 // The device path node that describes the Video Output Device Attributes for
  43 // the single head (UEFI child handle) that we support.
  44 //
  45 // The ACPI_DISPLAY_ADR() macro corresponds to Table B-2, section "B.4.2 _DOD"
  46 // in the ACPI 3.0b spec, or more recently, to Table B-379, section "B.3.2
  47 // _DOD" in the ACPI 6.0 spec.
  48 //
  49 STATIC CONST ACPI_ADR_DEVICE_PATH mAcpiAdr = {
  50   {                                         // Header
  51     ACPI_DEVICE_PATH,                       //   Type
  52     ACPI_ADR_DP,                            //   SubType
  53     { sizeof mAcpiAdr, 0 },                 //   Length
  54   },
  55   ACPI_DISPLAY_ADR (                        // ADR
  56     1,                                      //   DeviceIdScheme: use the ACPI
  57                                             //     bit-field definitions
  58     0,                                      //   HeadId
  59     0,                                      //   NonVgaOutput
  60     1,                                      //   BiosCanDetect
  61     0,                                      //   VendorInfo
  62     ACPI_ADR_DISPLAY_TYPE_EXTERNAL_DIGITAL, //   Type
  63     0,                                      //   Port
  64     0                                       //   Index
  65     )
  66 };
  67
  68 //
  69 // Component Name 2 Protocol implementation.
  70 //
  71 STATIC CONST EFI_UNICODE_STRING_TABLE mDriverNameTable[] = {
  72   { "en", L"Virtio GPU Driver" },
  73   { NULL, NULL                 }
  74 };
  75
  76 STATIC
  77 EFI_STATUS
  78 EFIAPI
  79 VirtioGpuGetDriverName (
  80   IN  EFI_COMPONENT_NAME2_PROTOCOL *This,
  81   IN  CHAR8                        *Language,
  82   OUT CHAR16                       **DriverName
  83   )
  84 {
  85   return LookupUnicodeString2 (Language, This->SupportedLanguages,
  86            mDriverNameTable, DriverName, FALSE /* Iso639Language */);
  87 }
  88
  89 STATIC
  90 EFI_STATUS
  91 EFIAPI
  92 VirtioGpuGetControllerName (
  93   IN  EFI_COMPONENT_NAME2_PROTOCOL *This,
  94   IN  EFI_HANDLE                   ControllerHandle,
  95   IN  EFI_HANDLE                   ChildHandle       OPTIONAL,
  96   IN  CHAR8                        *Language,
  97   OUT CHAR16                       **ControllerName
  98   )
  99 {
 100   EFI_STATUS Status;
 101   VGPU_DEV   *VgpuDev;
 102
 103   //
 104   // Look up the VGPU_DEV "protocol interface" on ControllerHandle.
 105   //
 106   Status = gBS->OpenProtocol (ControllerHandle, &gEfiCallerIdGuid,
 107                   (VOID **)&VgpuDev, gImageHandle, ControllerHandle,
 108                   EFI_OPEN_PROTOCOL_GET_PROTOCOL);
 109   if (EFI_ERROR (Status)) {
 110     return Status;
 111   }
 112   //
 113   // Sanity check: if we found gEfiCallerIdGuid on ControllerHandle, then we
 114   // keep its Virtio Device Protocol interface open BY_DRIVER.
 115   //
 116   ASSERT_EFI_ERROR (EfiTestManagedDevice (ControllerHandle, gImageHandle,
 117                       &gVirtioDeviceProtocolGuid));
 118
 119   if (ChildHandle == NULL) {
 120     //
 121     // The caller is querying the name of the VGPU_DEV controller.
 122     //
 123     return LookupUnicodeString2 (Language, This->SupportedLanguages,
 124              VgpuDev->BusName, ControllerName, FALSE /* Iso639Language */);
 125   }
 126
 127   //
 128   // Otherwise, the caller is looking for the name of the GOP child controller.
 129   // Check if it is asking about the GOP child controller that we manage. (The
 130   // condition below covers the case when we haven't produced the GOP child
 131   // controller yet, or we've destroyed it since.)
 132   //
 133   if (VgpuDev->Child == NULL || ChildHandle != VgpuDev->Child->GopHandle) {
 134     return EFI_UNSUPPORTED;
 135   }
 136   //
 137   // Sanity check: our GOP child controller keeps the VGPU_DEV controller's
 138   // Virtio Device Protocol interface open BY_CHILD_CONTROLLER.
 139   //
 140   ASSERT_EFI_ERROR (EfiTestChildHandle (ControllerHandle, ChildHandle,
 141                       &gVirtioDeviceProtocolGuid));
 142
 143   return LookupUnicodeString2 (Language, This->SupportedLanguages,
 144            VgpuDev->Child->GopName, ControllerName,
 145            FALSE /* Iso639Language */);
 146 }
 147
 148 STATIC CONST EFI_COMPONENT_NAME2_PROTOCOL mComponentName2 = {
 149   VirtioGpuGetDriverName,
 150   VirtioGpuGetControllerName,
 151   "en"                       // SupportedLanguages (RFC 4646)
 152 };
 153
 154 //
 155 // Helper functions for the Driver Binding Protocol Implementation.
 156 //
 157 /**
 158   Format the VGPU_DEV controller name, to be looked up and returned by
 159   VirtioGpuGetControllerName().
 160
 161   @param[in] ControllerHandle  The handle that identifies the VGPU_DEV
 162                                controller.
 163
 164   @param[in] AgentHandle       The handle of the agent that will attempt to
 165                                temporarily open the PciIo protocol. This is the
 166                                DriverBindingHandle member of the
 167                                EFI_DRIVER_BINDING_PROTOCOL whose Start()
 168                                function is calling this function.
 169
 170   @param[in] DevicePath        The device path that is installed on
 171                                ControllerHandle.
 172
 173   @param[out] ControllerName   A dynamically allocated unicode string that
 174                                unconditionally says "Virtio GPU Device", with a
 175                                PCI Segment:Bus:Device.Function location
 176                                optionally appended. The latter part is only
 177                                produced if DevicePath contains at least one
 178                                PciIo node; in that case, the most specific such
 179                                node is used for retrieving the location info.
 180                                The caller is responsible for freeing
 181                                ControllerName after use.
 182
 183   @retval EFI_SUCCESS           ControllerName has been formatted.
 184
 185   @retval EFI_OUT_OF_RESOURCES  Failed to allocate memory for ControllerName.
 186 **/
 187 STATIC
 188 EFI_STATUS
 189 FormatVgpuDevName (
 190   IN  EFI_HANDLE               ControllerHandle,
 191   IN  EFI_HANDLE               AgentHandle,
 192   IN  EFI_DEVICE_PATH_PROTOCOL *DevicePath,
 193   OUT CHAR16                   **ControllerName
 194   )
 195 {
 196   EFI_HANDLE          PciIoHandle;
 197   EFI_PCI_IO_PROTOCOL *PciIo;
 198   UINTN               Segment, Bus, Device, Function;
 199   STATIC CONST CHAR16 ControllerNameStem[] = L"Virtio GPU Device";
 200   UINTN               ControllerNameSize;
 201
 202   if (EFI_ERROR (gBS->LocateDevicePath (&gEfiPciIoProtocolGuid, &DevicePath,
 203                         &PciIoHandle)) ||
 204       EFI_ERROR (gBS->OpenProtocol (PciIoHandle, &gEfiPciIoProtocolGuid,
 205                         (VOID **)&PciIo, AgentHandle, ControllerHandle,
 206                         EFI_OPEN_PROTOCOL_GET_PROTOCOL)) ||
 207       EFI_ERROR (PciIo->GetLocation (PciIo, &Segment, &Bus, &Device,
 208                           &Function))) {
 209     //
 210     // Failed to retrieve location info, return verbatim copy of static string.
 211     //
 212     *ControllerName = AllocateCopyPool (sizeof ControllerNameStem,
 213                         ControllerNameStem);
 214     return (*ControllerName == NULL) ? EFI_OUT_OF_RESOURCES : EFI_SUCCESS;
 215   }
 216   //
 217   // Location info available, format ControllerName dynamically.
 218   //
 219   ControllerNameSize = sizeof ControllerNameStem + // includes L'\0'
 220                        sizeof (CHAR16) * (1 + 4 +  // Segment
 221                                           1 + 2 +  // Bus
 222                                           1 + 2 +  // Device
 223                                           1 + 1    // Function
 224                                           );
 225   *ControllerName = AllocatePool (ControllerNameSize);
 226   if (*ControllerName == NULL) {
 227     return EFI_OUT_OF_RESOURCES;
 228   }
 229
 230   UnicodeSPrintAsciiFormat (*ControllerName, ControllerNameSize,
 231     "%s %04x:%02x:%02x.%x", ControllerNameStem, (UINT32)Segment, (UINT32)Bus,
 232     (UINT32)Device, (UINT32)Function);
 233   return EFI_SUCCESS;
 234 }
 235
 236 /**
 237   Dynamically allocate and initialize the VGPU_GOP child object within an
 238   otherwise configured parent VGPU_DEV object.
 239
 240   This function adds a BY_CHILD_CONTROLLER reference to ParentBusController's
 241   VIRTIO_DEVICE_PROTOCOL interface.
 242
 243   @param[in,out] ParentBus        The pre-initialized VGPU_DEV object that the
 244                                   newly created VGPU_GOP object will be the
 245                                   child of.
 246
 247   @param[in] ParentDevicePath     The device path protocol instance that is
 248                                   installed on ParentBusController.
 249
 250   @param[in] ParentBusController  The UEFI controller handle on which the
 251                                   ParentBus VGPU_DEV object and the
 252                                   ParentDevicePath device path protocol are
 253                                   installed.
 254
 255   @param[in] DriverBindingHandle  The DriverBindingHandle member of
 256                                   EFI_DRIVER_BINDING_PROTOCOL whose Start()
 257                                   function is calling this function. It is
 258                                   passed as AgentHandle to gBS->OpenProtocol()
 259                                   when creating the BY_CHILD_CONTROLLER
 260                                   reference.
 261
 262   @retval EFI_SUCCESS           ParentBus->Child has been created and
 263                                 populated, and ParentBus->Child->GopHandle now
 264                                 references ParentBusController->VirtIo
 265                                 BY_CHILD_CONTROLLER.
 266
 267   @retval EFI_OUT_OF_RESOURCES  Memory allocation failed.
 268
 269   @return                       Error codes from underlying functions.
 270 **/
 271 STATIC
 272 EFI_STATUS
 273 InitVgpuGop (
 274   IN OUT VGPU_DEV                 *ParentBus,
 275   IN     EFI_DEVICE_PATH_PROTOCOL *ParentDevicePath,
 276   IN     EFI_HANDLE               ParentBusController,
 277   IN     EFI_HANDLE               DriverBindingHandle
 278   )
 279 {
 280   VGPU_GOP            *VgpuGop;
 281   EFI_STATUS          Status;
 282   CHAR16              *ParentBusName;
 283   STATIC CONST CHAR16 NameSuffix[] = L" Head #0";
 284   UINTN               NameSize;
 285   CHAR16              *Name;
 286   EFI_TPL             OldTpl;
 287   VOID                *ParentVirtIo;
 288
 289   VgpuGop = AllocateZeroPool (sizeof *VgpuGop);
 290   if (VgpuGop == NULL) {
 291     return EFI_OUT_OF_RESOURCES;
 292   }
 293
 294   VgpuGop->Signature = VGPU_GOP_SIG;
 295   VgpuGop->ParentBus = ParentBus;
 296
 297   //
 298   // Format a human-readable controller name for VGPU_GOP, and stash it for
 299   // VirtioGpuGetControllerName() to look up. We simply append NameSuffix to
 300   // ParentBus->BusName.
 301   //
 302   Status = LookupUnicodeString2 ("en", mComponentName2.SupportedLanguages,
 303              ParentBus->BusName, &ParentBusName, FALSE /* Iso639Language */);
 304   ASSERT_EFI_ERROR (Status);
 305   NameSize = StrSize (ParentBusName) - sizeof (CHAR16) + sizeof NameSuffix;
 306   Name = AllocatePool (NameSize);
 307   if (Name == NULL) {
 308     Status = EFI_OUT_OF_RESOURCES;
 309     goto FreeVgpuGop;
 310   }
 311   UnicodeSPrintAsciiFormat (Name, NameSize, "%s%s", ParentBusName, NameSuffix);
 312   Status = AddUnicodeString2 ("en", mComponentName2.SupportedLanguages,
 313              &VgpuGop->GopName, Name, FALSE /* Iso639Language */);
 314   FreePool (Name);
 315   if (EFI_ERROR (Status)) {
 316     goto FreeVgpuGop;
 317   }
 318
 319   //
 320   // Create the child device path.
 321   //
 322   VgpuGop->GopDevicePath = AppendDevicePathNode (ParentDevicePath,
 323                              &mAcpiAdr.Header);
 324   if (VgpuGop->GopDevicePath == NULL) {
 325     Status = EFI_OUT_OF_RESOURCES;
 326     goto FreeVgpuGopName;
 327   }
 328
 329   //
 330   // Mask protocol notify callbacks until we're done.
 331   //
 332   OldTpl = gBS->RaiseTPL (TPL_CALLBACK);
 333
 334   //
 335   // Create the child handle with the child device path.
 336   //
 337   Status = gBS->InstallProtocolInterface (&VgpuGop->GopHandle,
 338                   &gEfiDevicePathProtocolGuid, EFI_NATIVE_INTERFACE,
 339                   VgpuGop->GopDevicePath);
 340   if (EFI_ERROR (Status)) {
 341     goto FreeDevicePath;
 342   }
 343
 344   //
 345   // The child handle must present a reference to the parent handle's Virtio
 346   // Device Protocol interface.
 347   //
 348   Status = gBS->OpenProtocol (ParentBusController, &gVirtioDeviceProtocolGuid,
 349                   &ParentVirtIo, DriverBindingHandle, VgpuGop->GopHandle,
 350                   EFI_OPEN_PROTOCOL_BY_CHILD_CONTROLLER);
 351   if (EFI_ERROR (Status)) {
 352     goto UninstallDevicePath;
 353   }
 354   ASSERT (ParentVirtIo == ParentBus->VirtIo);
 355
 356   //
 357   // Initialize our Graphics Output Protocol.
 358   //
 359   // This means "nothing" for now.
 360   //
 361   Status = EFI_SUCCESS;
 362   if (EFI_ERROR (Status)) {
 363     goto CloseVirtIoByChild;
 364   }
 365
 366   //
 367   // Install the Graphics Output Protocol on the child handle.
 368   //
 369   Status = gBS->InstallProtocolInterface (&VgpuGop->GopHandle,
 370                   &mDummyGraphicsOutputProtocolGuid, EFI_NATIVE_INTERFACE,
 371                   &VgpuGop->Gop);
 372   if (EFI_ERROR (Status)) {
 373     goto UninitGop;
 374   }
 375
 376   //
 377   // We're done.
 378   //
 379   gBS->RestoreTPL (OldTpl);
 380   ParentBus->Child = VgpuGop;
 381   return EFI_SUCCESS;
 382
 383 UninitGop:
 384   //
 385   // Nothing, for now.
 386   //
 387
 388 CloseVirtIoByChild:
 389   gBS->CloseProtocol (ParentBusController, &gVirtioDeviceProtocolGuid,
 390     DriverBindingHandle, VgpuGop->GopHandle);
 391
 392 UninstallDevicePath:
 393   gBS->UninstallProtocolInterface (VgpuGop->GopHandle,
 394          &gEfiDevicePathProtocolGuid, VgpuGop->GopDevicePath);
 395
 396 FreeDevicePath:
 397   gBS->RestoreTPL (OldTpl);
 398   FreePool (VgpuGop->GopDevicePath);
 399
 400 FreeVgpuGopName:
 401   FreeUnicodeStringTable (VgpuGop->GopName);
 402
 403 FreeVgpuGop:
 404   FreePool (VgpuGop);
 405
 406   return Status;
 407 }
 408
 409 /**
 410   Tear down and release the VGPU_GOP child object within the VGPU_DEV parent
 411   object.
 412
 413   This function removes the BY_CHILD_CONTROLLER reference from
 414   ParentBusController's VIRTIO_DEVICE_PROTOCOL interface.
 415
 416   @param[in,out] ParentBus        The VGPU_DEV object that the VGPU_GOP child
 417                                   object will be removed from.
 418
 419   @param[in] ParentBusController  The UEFI controller handle on which the
 420                                   ParentBus VGPU_DEV object is installed.
 421
 422   @param[in] DriverBindingHandle  The DriverBindingHandle member of
 423                                   EFI_DRIVER_BINDING_PROTOCOL whose Stop()
 424                                   function is calling this function. It is
 425                                   passed as AgentHandle to gBS->CloseProtocol()
 426                                   when removing the BY_CHILD_CONTROLLER
 427                                   reference.
 428 **/
 429 STATIC
 430 VOID
 431 UninitVgpuGop (
 432   IN OUT VGPU_DEV   *ParentBus,
 433   IN     EFI_HANDLE ParentBusController,
 434   IN     EFI_HANDLE DriverBindingHandle
 435   )
 436 {
 437   VGPU_GOP   *VgpuGop;
 438   EFI_STATUS Status;
 439
 440   VgpuGop = ParentBus->Child;
 441   Status = gBS->UninstallProtocolInterface (VgpuGop->GopHandle,
 442                   &mDummyGraphicsOutputProtocolGuid, &VgpuGop->Gop);
 443   ASSERT_EFI_ERROR (Status);
 444
 445   //
 446   // Uninitialize VgpuGop->Gop.
 447   //
 448   // Nothing, for now.
 449   //
 450   Status = EFI_SUCCESS;
 451   ASSERT_EFI_ERROR (Status);
 452
 453   Status = gBS->CloseProtocol (ParentBusController, &gVirtioDeviceProtocolGuid,
 454                   DriverBindingHandle, VgpuGop->GopHandle);
 455   ASSERT_EFI_ERROR (Status);
 456
 457   Status = gBS->UninstallProtocolInterface (VgpuGop->GopHandle,
 458                   &gEfiDevicePathProtocolGuid, VgpuGop->GopDevicePath);
 459   ASSERT_EFI_ERROR (Status);
 460
 461   FreePool (VgpuGop->GopDevicePath);
 462   FreeUnicodeStringTable (VgpuGop->GopName);
 463   FreePool (VgpuGop);
 464
 465   ParentBus->Child = NULL;
 466 }
 467
 468 //
 469 // Driver Binding Protocol Implementation.
 470 //
 471 STATIC
 472 EFI_STATUS
 473 EFIAPI
 474 VirtioGpuDriverBindingSupported (
 475   IN EFI_DRIVER_BINDING_PROTOCOL *This,
 476   IN EFI_HANDLE                  ControllerHandle,
 477   IN EFI_DEVICE_PATH_PROTOCOL    *RemainingDevicePath OPTIONAL
 478   )
 479 {
 480   EFI_STATUS             Status;
 481   VIRTIO_DEVICE_PROTOCOL *VirtIo;
 482
 483   //
 484   // - If RemainingDevicePath is NULL: the caller is interested in creating all
 485   //   child handles.
 486   // - If RemainingDevicePath points to an end node: the caller is not
 487   //   interested in creating any child handle.
 488   // - Otherwise, the caller would like to create the one child handle
 489   //   specified in RemainingDevicePath. In this case we have to see if the
 490   //   requested device path is supportable.
 491   //
 492   if (RemainingDevicePath != NULL &&
 493       !IsDevicePathEnd (RemainingDevicePath) &&
 494       (DevicePathNodeLength (RemainingDevicePath) != sizeof mAcpiAdr ||
 495        CompareMem (RemainingDevicePath, &mAcpiAdr, sizeof mAcpiAdr) != 0)) {
 496     return EFI_UNSUPPORTED;
 497   }
 498
 499   //
 500   // Open the Virtio Device Protocol interface on the controller, BY_DRIVER.
 501   //
 502   Status = gBS->OpenProtocol (ControllerHandle, &gVirtioDeviceProtocolGuid,
 503                   (VOID **)&VirtIo, This->DriverBindingHandle,
 504                   ControllerHandle, EFI_OPEN_PROTOCOL_BY_DRIVER);
 505   if (EFI_ERROR (Status)) {
 506     //
 507     // If this fails, then by default we cannot support ControllerHandle. There
 508     // is one exception: we've already bound the device, have not produced any
 509     // GOP child controller, and now the caller wants us to produce the child
 510     // controller (either specifically or as part of "all children"). That's
 511     // allowed.
 512     //
 513     if (Status == EFI_ALREADY_STARTED) {
 514       EFI_STATUS Status2;
 515       VGPU_DEV   *VgpuDev;
 516
 517       Status2 = gBS->OpenProtocol (ControllerHandle, &gEfiCallerIdGuid,
 518                        (VOID **)&VgpuDev, This->DriverBindingHandle,
 519                        ControllerHandle, EFI_OPEN_PROTOCOL_GET_PROTOCOL);
 520       ASSERT_EFI_ERROR (Status2);
 521
 522       if (VgpuDev->Child == NULL &&
 523           (RemainingDevicePath == NULL ||
 524            !IsDevicePathEnd (RemainingDevicePath))) {
 525         Status = EFI_SUCCESS;
 526       }
 527     }
 528
 529     return Status;
 530   }
 531
 532   //
 533   // First BY_DRIVER open; check the VirtIo revision and subsystem.
 534   //
 535   if (VirtIo->Revision < VIRTIO_SPEC_REVISION (1, 0, 0) ||
 536       VirtIo->SubSystemDeviceId != VIRTIO_SUBSYSTEM_GPU_DEVICE) {
 537     Status = EFI_UNSUPPORTED;
 538     goto CloseVirtIo;
 539   }
 540
 541   //
 542   // We'll need the device path of the VirtIo device both for formatting
 543   // VGPU_DEV.BusName and for populating VGPU_GOP.GopDevicePath.
 544   //
 545   Status = gBS->OpenProtocol (ControllerHandle, &gEfiDevicePathProtocolGuid,
 546                   NULL, This->DriverBindingHandle, ControllerHandle,
 547                   EFI_OPEN_PROTOCOL_TEST_PROTOCOL);
 548
 549 CloseVirtIo:
 550   gBS->CloseProtocol (ControllerHandle, &gVirtioDeviceProtocolGuid,
 551     This->DriverBindingHandle, ControllerHandle);
 552
 553   return Status;
 554 }
 555
 556 STATIC
 557 EFI_STATUS
 558 EFIAPI
 559 VirtioGpuDriverBindingStart (
 560   IN EFI_DRIVER_BINDING_PROTOCOL *This,
 561   IN EFI_HANDLE                  ControllerHandle,
 562   IN EFI_DEVICE_PATH_PROTOCOL    *RemainingDevicePath OPTIONAL
 563   )
 564 {
 565   EFI_STATUS               Status;
 566   VIRTIO_DEVICE_PROTOCOL   *VirtIo;
 567   BOOLEAN                  VirtIoBoundJustNow;
 568   VGPU_DEV                 *VgpuDev;
 569   EFI_DEVICE_PATH_PROTOCOL *DevicePath;
 570
 571   //
 572   // Open the Virtio Device Protocol.
 573   //
 574   // The result of this operation, combined with the checks in
 575   // VirtioGpuDriverBindingSupported(), uniquely tells us whether we are
 576   // binding the VirtIo controller on this call (with or without creating child
 577   // controllers), or else we're *only* creating child controllers.
 578   //
 579   Status = gBS->OpenProtocol (ControllerHandle, &gVirtioDeviceProtocolGuid,
 580                   (VOID **)&VirtIo, This->DriverBindingHandle,
 581                   ControllerHandle, EFI_OPEN_PROTOCOL_BY_DRIVER);
 582   if (EFI_ERROR (Status)) {
 583     //
 584     // The assertions below are based on the success of
 585     // VirtioGpuDriverBindingSupported(): we bound ControllerHandle earlier,
 586     // without producing child handles, and now we're producing the GOP child
 587     // handle only.
 588     //
 589     ASSERT (Status == EFI_ALREADY_STARTED);
 590
 591     Status = gBS->OpenProtocol (ControllerHandle, &gEfiCallerIdGuid,
 592                     (VOID **)&VgpuDev, This->DriverBindingHandle,
 593                     ControllerHandle, EFI_OPEN_PROTOCOL_GET_PROTOCOL);
 594     ASSERT_EFI_ERROR (Status);
 595
 596     ASSERT (VgpuDev->Child == NULL);
 597     ASSERT (
 598       RemainingDevicePath == NULL || !IsDevicePathEnd (RemainingDevicePath));
 599
 600     VirtIoBoundJustNow = FALSE;
 601   } else {
 602     VirtIoBoundJustNow = TRUE;
 603
 604     //
 605     // Allocate the private structure.
 606     //
 607     VgpuDev = AllocateZeroPool (sizeof *VgpuDev);
 608     if (VgpuDev == NULL) {
 609       Status = EFI_OUT_OF_RESOURCES;
 610       goto CloseVirtIo;
 611     }
 612     VgpuDev->VirtIo = VirtIo;
 613   }
 614
 615   //
 616   // Grab the VirtIo controller's device path. This is necessary regardless of
 617   // VirtIoBoundJustNow.
 618   //
 619   Status = gBS->OpenProtocol (ControllerHandle, &gEfiDevicePathProtocolGuid,
 620                   (VOID **)&DevicePath, This->DriverBindingHandle,
 621                   ControllerHandle, EFI_OPEN_PROTOCOL_GET_PROTOCOL);
 622   if (EFI_ERROR (Status)) {
 623     goto FreeVgpuDev;
 624   }
 625
 626   //
 627   // Create VGPU_DEV if we've bound the VirtIo controller right now (that is,
 628   // if we aren't *only* creating child handles).
 629   //
 630   if (VirtIoBoundJustNow) {
 631     CHAR16 *VgpuDevName;
 632
 633     //
 634     // Format a human-readable controller name for VGPU_DEV, and stash it for
 635     // VirtioGpuGetControllerName() to look up.
 636     //
 637     Status = FormatVgpuDevName (ControllerHandle, This->DriverBindingHandle,
 638                DevicePath, &VgpuDevName);
 639     if (EFI_ERROR (Status)) {
 640       goto FreeVgpuDev;
 641     }
 642     Status = AddUnicodeString2 ("en", mComponentName2.SupportedLanguages,
 643                &VgpuDev->BusName, VgpuDevName, FALSE /* Iso639Language */);
 644     FreePool (VgpuDevName);
 645     if (EFI_ERROR (Status)) {
 646       goto FreeVgpuDev;
 647     }
 648
 649     //
 650     // Install the VGPU_DEV "protocol interface" on ControllerHandle.
 651     //
 652     Status = gBS->InstallProtocolInterface (&ControllerHandle,
 653                     &gEfiCallerIdGuid, EFI_NATIVE_INTERFACE, VgpuDev);
 654     if (EFI_ERROR (Status)) {
 655       goto FreeVgpuDevBusName;
 656     }
 657
 658     if (RemainingDevicePath != NULL && IsDevicePathEnd (RemainingDevicePath)) {
 659       //
 660       // No child handle should be produced; we're done.
 661       //
 662       DEBUG ((EFI_D_INFO, "%a: bound VirtIo=%p without producing GOP\n",
 663         __FUNCTION__, (VOID *)VgpuDev->VirtIo));
 664       return EFI_SUCCESS;
 665     }
 666   }
 667
 668   //
 669   // Below we'll produce our single child handle: the caller requested it
 670   // either specifically, or as part of all child handles.
 671   //
 672   ASSERT (VgpuDev->Child == NULL);
 673   ASSERT (
 674     RemainingDevicePath == NULL || !IsDevicePathEnd (RemainingDevicePath));
 675
 676   Status = InitVgpuGop (VgpuDev, DevicePath, ControllerHandle,
 677              This->DriverBindingHandle);
 678   if (EFI_ERROR (Status)) {
 679     goto UninstallVgpuDev;
 680   }
 681
 682   //
 683   // We're done.
 684   //
 685   DEBUG ((EFI_D_INFO, "%a: produced GOP %a VirtIo=%p\n", __FUNCTION__,
 686     VirtIoBoundJustNow ? "while binding" : "for pre-bound",
 687     (VOID *)VgpuDev->VirtIo));
 688   return EFI_SUCCESS;
 689
 690 UninstallVgpuDev:
 691   if (VirtIoBoundJustNow) {
 692     gBS->UninstallProtocolInterface (ControllerHandle, &gEfiCallerIdGuid,
 693            VgpuDev);
 694   }
 695
 696 FreeVgpuDevBusName:
 697   if (VirtIoBoundJustNow) {
 698     FreeUnicodeStringTable (VgpuDev->BusName);
 699   }
 700
 701 FreeVgpuDev:
 702   if (VirtIoBoundJustNow) {
 703     FreePool (VgpuDev);
 704   }
 705
 706 CloseVirtIo:
 707   if (VirtIoBoundJustNow) {
 708     gBS->CloseProtocol (ControllerHandle, &gVirtioDeviceProtocolGuid,
 709       This->DriverBindingHandle, ControllerHandle);
 710   }
 711
 712   return Status;
 713 }
 714
 715 STATIC
 716 EFI_STATUS
 717 EFIAPI
 718 VirtioGpuDriverBindingStop (
 719   IN  EFI_DRIVER_BINDING_PROTOCOL *This,
 720   IN  EFI_HANDLE                  ControllerHandle,
 721   IN  UINTN                       NumberOfChildren,
 722   IN  EFI_HANDLE                  *ChildHandleBuffer OPTIONAL
 723   )
 724 {
 725   EFI_STATUS Status;
 726   VGPU_DEV   *VgpuDev;
 727
 728   //
 729   // Look up the VGPU_DEV "protocol interface" on ControllerHandle.
 730   //
 731   Status = gBS->OpenProtocol (ControllerHandle, &gEfiCallerIdGuid,
 732                   (VOID **)&VgpuDev, This->DriverBindingHandle,
 733                   ControllerHandle, EFI_OPEN_PROTOCOL_GET_PROTOCOL);
 734   if (EFI_ERROR (Status)) {
 735     return Status;
 736   }
 737   //
 738   // Sanity check: if we found gEfiCallerIdGuid on ControllerHandle, then we
 739   // keep its Virtio Device Protocol interface open BY_DRIVER.
 740   //
 741   ASSERT_EFI_ERROR (EfiTestManagedDevice (ControllerHandle,
 742                       This->DriverBindingHandle, &gVirtioDeviceProtocolGuid));
 743
 744   switch (NumberOfChildren) {
 745   case 0:
 746     //
 747     // The caller wants us to unbind the VirtIo controller.
 748     //
 749     if (VgpuDev->Child != NULL) {
 750       //
 751       // We still have the GOP child.
 752       //
 753       Status = EFI_DEVICE_ERROR;
 754       break;
 755     }
 756
 757     DEBUG ((EFI_D_INFO, "%a: unbinding GOP-less VirtIo=%p\n", __FUNCTION__,
 758       (VOID *)VgpuDev->VirtIo));
 759
 760     Status = gBS->UninstallProtocolInterface (ControllerHandle,
 761                     &gEfiCallerIdGuid, VgpuDev);
 762     ASSERT_EFI_ERROR (Status);
 763
 764     FreeUnicodeStringTable (VgpuDev->BusName);
 765     FreePool (VgpuDev);
 766
 767     Status = gBS->CloseProtocol (ControllerHandle, &gVirtioDeviceProtocolGuid,
 768                     This->DriverBindingHandle, ControllerHandle);
 769     ASSERT_EFI_ERROR (Status);
 770     break;
 771
 772   case 1:
 773     //
 774     // The caller wants us to destroy our child GOP controller.
 775     //
 776     if (VgpuDev->Child == NULL ||
 777         ChildHandleBuffer[0] != VgpuDev->Child->GopHandle) {
 778       //
 779       // We have no child controller at the moment, or it differs from the one
 780       // the caller wants us to destroy. I.e., we don't own the child
 781       // controller passed in.
 782       //
 783       Status = EFI_DEVICE_ERROR;
 784       break;
 785     }
 786     //
 787     // Sanity check: our GOP child controller keeps the VGPU_DEV controller's
 788     // Virtio Device Protocol interface open BY_CHILD_CONTROLLER.
 789     //
 790     ASSERT_EFI_ERROR (EfiTestChildHandle (ControllerHandle,
 791                         VgpuDev->Child->GopHandle,
 792                         &gVirtioDeviceProtocolGuid));
 793
 794     DEBUG ((EFI_D_INFO, "%a: destroying GOP under VirtIo=%p\n", __FUNCTION__,
 795       (VOID *)VgpuDev->VirtIo));
 796     UninitVgpuGop (VgpuDev, ControllerHandle, This->DriverBindingHandle);
 797     break;
 798
 799   default:
 800     //
 801     // Impossible, we never produced more than one child.
 802     //
 803     Status = EFI_DEVICE_ERROR;
 804     break;
 805   }
 806   return Status;
 807 }
 808
 809 STATIC EFI_DRIVER_BINDING_PROTOCOL mDriverBinding = {
 810   VirtioGpuDriverBindingSupported,
 811   VirtioGpuDriverBindingStart,
 812   VirtioGpuDriverBindingStop,
 813   0x10,                            // Version
 814   NULL,                            // ImageHandle, overwritten in entry point
 815   NULL                             // DriverBindingHandle, ditto
 816 };
 817
 818 //
 819 // Entry point of the driver.
 820 //
 821 EFI_STATUS
 822 EFIAPI
 823 VirtioGpuEntryPoint (
 824   IN EFI_HANDLE       ImageHandle,
 825   IN EFI_SYSTEM_TABLE *SystemTable
 826   )
 827 {
 828   return EfiLibInstallDriverBindingComponentName2 (ImageHandle, SystemTable,
 829            &mDriverBinding, ImageHandle, NULL /* ComponentName */,
 830            &mComponentName2);
 831 }