[mirror_edk2.git] / OvmfPkg / VirtioGpuDxe / DriverBinding.c

/** @file\r
\r
  Implement the Driver Binding Protocol and the Component Name 2 Protocol for\r
  the Virtio GPU hybrid driver.\r
\r
  Copyright (C) 2016, Red Hat, Inc.\r
\r
  SPDX-License-Identifier: BSD-2-Clause-Patent\r
\r
**/\r
\r
#include <Library/DevicePathLib.h>\r
#include <Library/MemoryAllocationLib.h>\r
#include <Library/PrintLib.h>\r
#include <Library/UefiBootServicesTableLib.h>\r
#include <Library/UefiLib.h>\r
#include <Protocol/ComponentName2.h>\r
#include <Protocol/DevicePath.h>\r
#include <Protocol/DriverBinding.h>\r
#include <Protocol/PciIo.h>\r
\r
#include "VirtioGpu.h"\r
\r
//\r
// The device path node that describes the Video Output Device Attributes for\r
// the single head (UEFI child handle) that we support.\r
//\r
// The ACPI_DISPLAY_ADR() macro corresponds to Table B-2, section "B.4.2 _DOD"\r
// in the ACPI 3.0b spec, or more recently, to Table B-379, section "B.3.2\r
// _DOD" in the ACPI 6.0 spec.\r
//\r
STATIC CONST ACPI_ADR_DEVICE_PATH mAcpiAdr = {\r
  {                                         // Header\r
    ACPI_DEVICE_PATH,                       //   Type\r
    ACPI_ADR_DP,                            //   SubType\r
    { sizeof mAcpiAdr, 0 },                 //   Length\r
  },\r
  ACPI_DISPLAY_ADR (                        // ADR\r
    1,                                      //   DeviceIdScheme: use the ACPI\r
                                            //     bit-field definitions\r
    0,                                      //   HeadId\r
    0,                                      //   NonVgaOutput\r
    1,                                      //   BiosCanDetect\r
    0,                                      //   VendorInfo\r
    ACPI_ADR_DISPLAY_TYPE_EXTERNAL_DIGITAL, //   Type\r
    0,                                      //   Port\r
    0                                       //   Index\r
    )\r
};\r
\r
//\r
// Component Name 2 Protocol implementation.\r
//\r
STATIC CONST EFI_UNICODE_STRING_TABLE mDriverNameTable[] = {\r
  { "en", L"Virtio GPU Driver" },\r
  { NULL, NULL                 }\r
};\r
\r
STATIC\r
EFI_STATUS\r
EFIAPI\r
VirtioGpuGetDriverName (\r
  IN  EFI_COMPONENT_NAME2_PROTOCOL *This,\r
  IN  CHAR8                        *Language,\r
  OUT CHAR16                       **DriverName\r
  )\r
{\r
  return LookupUnicodeString2 (Language, This->SupportedLanguages,\r
           mDriverNameTable, DriverName, FALSE /* Iso639Language */);\r
}\r
\r
STATIC\r
EFI_STATUS\r
EFIAPI\r
VirtioGpuGetControllerName (\r
  IN  EFI_COMPONENT_NAME2_PROTOCOL *This,\r
  IN  EFI_HANDLE                   ControllerHandle,\r
  IN  EFI_HANDLE                   ChildHandle       OPTIONAL,\r
  IN  CHAR8                        *Language,\r
  OUT CHAR16                       **ControllerName\r
  )\r
{\r
  EFI_STATUS Status;\r
  VGPU_DEV   *VgpuDev;\r
\r
  //\r
  // Look up the VGPU_DEV "protocol interface" on ControllerHandle.\r
  //\r
  Status = gBS->OpenProtocol (ControllerHandle, &gEfiCallerIdGuid,\r
                  (VOID **)&VgpuDev, gImageHandle, ControllerHandle,\r
                  EFI_OPEN_PROTOCOL_GET_PROTOCOL);\r
  if (EFI_ERROR (Status)) {\r
    return Status;\r
  }\r
  //\r
  // Sanity check: if we found gEfiCallerIdGuid on ControllerHandle, then we\r
  // keep its Virtio Device Protocol interface open BY_DRIVER.\r
  //\r
  ASSERT_EFI_ERROR (EfiTestManagedDevice (ControllerHandle, gImageHandle,\r
                      &gVirtioDeviceProtocolGuid));\r
\r
  if (ChildHandle == NULL) {\r
    //\r
    // The caller is querying the name of the VGPU_DEV controller.\r
    //\r
    return LookupUnicodeString2 (Language, This->SupportedLanguages,\r
             VgpuDev->BusName, ControllerName, FALSE /* Iso639Language */);\r
  }\r
\r
  //\r
  // Otherwise, the caller is looking for the name of the GOP child controller.\r
  // Check if it is asking about the GOP child controller that we manage. (The\r
  // condition below covers the case when we haven't produced the GOP child\r
  // controller yet, or we've destroyed it since.)\r
  //\r
  if (VgpuDev->Child == NULL || ChildHandle != VgpuDev->Child->GopHandle) {\r
    return EFI_UNSUPPORTED;\r
  }\r
  //\r
  // Sanity check: our GOP child controller keeps the VGPU_DEV controller's\r
  // Virtio Device Protocol interface open BY_CHILD_CONTROLLER.\r
  //\r
  ASSERT_EFI_ERROR (EfiTestChildHandle (ControllerHandle, ChildHandle,\r
                      &gVirtioDeviceProtocolGuid));\r
\r
  return LookupUnicodeString2 (Language, This->SupportedLanguages,\r
           VgpuDev->Child->GopName, ControllerName,\r
           FALSE /* Iso639Language */);\r
}\r
\r
STATIC CONST EFI_COMPONENT_NAME2_PROTOCOL mComponentName2 = {\r
  VirtioGpuGetDriverName,\r
  VirtioGpuGetControllerName,\r
  "en"                       // SupportedLanguages (RFC 4646)\r
};\r
\r
//\r
// Helper functions for the Driver Binding Protocol Implementation.\r
//\r
/**\r
  Format the VGPU_DEV controller name, to be looked up and returned by\r
  VirtioGpuGetControllerName().\r
\r
  @param[in] ControllerHandle  The handle that identifies the VGPU_DEV\r
                               controller.\r
\r
  @param[in] AgentHandle       The handle of the agent that will attempt to\r
                               temporarily open the PciIo protocol. This is the\r
                               DriverBindingHandle member of the\r
                               EFI_DRIVER_BINDING_PROTOCOL whose Start()\r
                               function is calling this function.\r
\r
  @param[in] DevicePath        The device path that is installed on\r
                               ControllerHandle.\r
\r
  @param[out] ControllerName   A dynamically allocated unicode string that\r
                               unconditionally says "Virtio GPU Device", with a\r
                               PCI Segment:Bus:Device.Function location\r
                               optionally appended. The latter part is only\r
                               produced if DevicePath contains at least one\r
                               PciIo node; in that case, the most specific such\r
                               node is used for retrieving the location info.\r
                               The caller is responsible for freeing\r
                               ControllerName after use.\r
\r
  @retval EFI_SUCCESS           ControllerName has been formatted.\r
\r
  @retval EFI_OUT_OF_RESOURCES  Failed to allocate memory for ControllerName.\r
**/\r
STATIC\r
EFI_STATUS\r
FormatVgpuDevName (\r
  IN  EFI_HANDLE               ControllerHandle,\r
  IN  EFI_HANDLE               AgentHandle,\r
  IN  EFI_DEVICE_PATH_PROTOCOL *DevicePath,\r
  OUT CHAR16                   **ControllerName\r
  )\r
{\r
  EFI_HANDLE          PciIoHandle;\r
  EFI_PCI_IO_PROTOCOL *PciIo;\r
  UINTN               Segment, Bus, Device, Function;\r
  STATIC CONST CHAR16 ControllerNameStem[] = L"Virtio GPU Device";\r
  UINTN               ControllerNameSize;\r
\r
  if (EFI_ERROR (gBS->LocateDevicePath (&gEfiPciIoProtocolGuid, &DevicePath,\r
                        &PciIoHandle)) ||\r
      EFI_ERROR (gBS->OpenProtocol (PciIoHandle, &gEfiPciIoProtocolGuid,\r
                        (VOID **)&PciIo, AgentHandle, ControllerHandle,\r
                        EFI_OPEN_PROTOCOL_GET_PROTOCOL)) ||\r
      EFI_ERROR (PciIo->GetLocation (PciIo, &Segment, &Bus, &Device,\r
                          &Function))) {\r
    //\r
    // Failed to retrieve location info, return verbatim copy of static string.\r
    //\r
    *ControllerName = AllocateCopyPool (sizeof ControllerNameStem,\r
                        ControllerNameStem);\r
    return (*ControllerName == NULL) ? EFI_OUT_OF_RESOURCES : EFI_SUCCESS;\r
  }\r
  //\r
  // Location info available, format ControllerName dynamically.\r
  //\r
  ControllerNameSize = sizeof ControllerNameStem + // includes L'\0'\r
                       sizeof (CHAR16) * (1 + 4 +  // Segment\r
                                          1 + 2 +  // Bus\r
                                          1 + 2 +  // Device\r
                                          1 + 1    // Function\r
                                          );\r
  *ControllerName = AllocatePool (ControllerNameSize);\r
  if (*ControllerName == NULL) {\r
    return EFI_OUT_OF_RESOURCES;\r
  }\r
\r
  UnicodeSPrintAsciiFormat (*ControllerName, ControllerNameSize,\r
    "%s %04x:%02x:%02x.%x", ControllerNameStem, (UINT32)Segment, (UINT32)Bus,\r
    (UINT32)Device, (UINT32)Function);\r
  return EFI_SUCCESS;\r
}\r
\r
/**\r
  Dynamically allocate and initialize the VGPU_GOP child object within an\r
  otherwise configured parent VGPU_DEV object.\r
\r
  This function adds a BY_CHILD_CONTROLLER reference to ParentBusController's\r
  VIRTIO_DEVICE_PROTOCOL interface.\r
\r
  @param[in,out] ParentBus        The pre-initialized VGPU_DEV object that the\r
                                  newly created VGPU_GOP object will be the\r
                                  child of.\r
\r
  @param[in] ParentDevicePath     The device path protocol instance that is\r
                                  installed on ParentBusController.\r
\r
  @param[in] ParentBusController  The UEFI controller handle on which the\r
                                  ParentBus VGPU_DEV object and the\r
                                  ParentDevicePath device path protocol are\r
                                  installed.\r
\r
  @param[in] DriverBindingHandle  The DriverBindingHandle member of\r
                                  EFI_DRIVER_BINDING_PROTOCOL whose Start()\r
                                  function is calling this function. It is\r
                                  passed as AgentHandle to gBS->OpenProtocol()\r
                                  when creating the BY_CHILD_CONTROLLER\r
                                  reference.\r
\r
  @retval EFI_SUCCESS           ParentBus->Child has been created and\r
                                populated, and ParentBus->Child->GopHandle now\r
                                references ParentBusController->VirtIo\r
                                BY_CHILD_CONTROLLER.\r
\r
  @retval EFI_OUT_OF_RESOURCES  Memory allocation failed.\r
\r
  @return                       Error codes from underlying functions.\r
**/\r
STATIC\r
EFI_STATUS\r
InitVgpuGop (\r
  IN OUT VGPU_DEV                 *ParentBus,\r
  IN     EFI_DEVICE_PATH_PROTOCOL *ParentDevicePath,\r
  IN     EFI_HANDLE               ParentBusController,\r
  IN     EFI_HANDLE               DriverBindingHandle\r
  )\r
{\r
  VGPU_GOP            *VgpuGop;\r
  EFI_STATUS          Status;\r
  CHAR16              *ParentBusName;\r
  STATIC CONST CHAR16 NameSuffix[] = L" Head #0";\r
  UINTN               NameSize;\r
  CHAR16              *Name;\r
  EFI_TPL             OldTpl;\r
  VOID                *ParentVirtIo;\r
\r
  VgpuGop = AllocateZeroPool (sizeof *VgpuGop);\r
  if (VgpuGop == NULL) {\r
    return EFI_OUT_OF_RESOURCES;\r
  }\r
\r
  VgpuGop->Signature = VGPU_GOP_SIG;\r
  VgpuGop->ParentBus = ParentBus;\r
\r
  //\r
  // Format a human-readable controller name for VGPU_GOP, and stash it for\r
  // VirtioGpuGetControllerName() to look up. We simply append NameSuffix to\r
  // ParentBus->BusName.\r
  //\r
  Status = LookupUnicodeString2 ("en", mComponentName2.SupportedLanguages,\r
             ParentBus->BusName, &ParentBusName, FALSE /* Iso639Language */);\r
  ASSERT_EFI_ERROR (Status);\r
  NameSize = StrSize (ParentBusName) - sizeof (CHAR16) + sizeof NameSuffix;\r
  Name = AllocatePool (NameSize);\r
  if (Name == NULL) {\r
    Status = EFI_OUT_OF_RESOURCES;\r
    goto FreeVgpuGop;\r
  }\r
  UnicodeSPrintAsciiFormat (Name, NameSize, "%s%s", ParentBusName, NameSuffix);\r
  Status = AddUnicodeString2 ("en", mComponentName2.SupportedLanguages,\r
             &VgpuGop->GopName, Name, FALSE /* Iso639Language */);\r
  FreePool (Name);\r
  if (EFI_ERROR (Status)) {\r
    goto FreeVgpuGop;\r
  }\r
\r
  //\r
  // Create the child device path.\r
  //\r
  VgpuGop->GopDevicePath = AppendDevicePathNode (ParentDevicePath,\r
                             &mAcpiAdr.Header);\r
  if (VgpuGop->GopDevicePath == NULL) {\r
    Status = EFI_OUT_OF_RESOURCES;\r
    goto FreeVgpuGopName;\r
  }\r
\r
  //\r
  // Mask protocol notify callbacks until we're done.\r
  //\r
  OldTpl = gBS->RaiseTPL (TPL_CALLBACK);\r
\r
  //\r
  // Create the child handle with the child device path.\r
  //\r
  Status = gBS->InstallProtocolInterface (&VgpuGop->GopHandle,\r
                  &gEfiDevicePathProtocolGuid, EFI_NATIVE_INTERFACE,\r
                  VgpuGop->GopDevicePath);\r
  if (EFI_ERROR (Status)) {\r
    goto FreeDevicePath;\r
  }\r
\r
  //\r
  // The child handle must present a reference to the parent handle's Virtio\r
  // Device Protocol interface.\r
  //\r
  Status = gBS->OpenProtocol (ParentBusController, &gVirtioDeviceProtocolGuid,\r
                  &ParentVirtIo, DriverBindingHandle, VgpuGop->GopHandle,\r
                  EFI_OPEN_PROTOCOL_BY_CHILD_CONTROLLER);\r
  if (EFI_ERROR (Status)) {\r
    goto UninstallDevicePath;\r
  }\r
  ASSERT (ParentVirtIo == ParentBus->VirtIo);\r
\r
  //\r
  // Initialize our Graphics Output Protocol.\r
  //\r
  // Fill in the function members of VgpuGop->Gop from the template, then set\r
  // up the rest of the GOP infrastructure by calling SetMode() right now.\r
  //\r
  CopyMem (&VgpuGop->Gop, &mGopTemplate, sizeof mGopTemplate);\r
  Status = VgpuGop->Gop.SetMode (&VgpuGop->Gop, 0);\r
  if (EFI_ERROR (Status)) {\r
    goto CloseVirtIoByChild;\r
  }\r
\r
  //\r
  // Install the Graphics Output Protocol on the child handle.\r
  //\r
  Status = gBS->InstallProtocolInterface (&VgpuGop->GopHandle,\r
                  &gEfiGraphicsOutputProtocolGuid, EFI_NATIVE_INTERFACE,\r
                  &VgpuGop->Gop);\r
  if (EFI_ERROR (Status)) {\r
    goto UninitGop;\r
  }\r
\r
  //\r
  // We're done.\r
  //\r
  gBS->RestoreTPL (OldTpl);\r
  ParentBus->Child = VgpuGop;\r
  return EFI_SUCCESS;\r
\r
UninitGop:\r
  ReleaseGopResources (VgpuGop, TRUE /* DisableHead */);\r
\r
CloseVirtIoByChild:\r
  gBS->CloseProtocol (ParentBusController, &gVirtioDeviceProtocolGuid,\r
    DriverBindingHandle, VgpuGop->GopHandle);\r
\r
UninstallDevicePath:\r
  gBS->UninstallProtocolInterface (VgpuGop->GopHandle,\r
         &gEfiDevicePathProtocolGuid, VgpuGop->GopDevicePath);\r
\r
FreeDevicePath:\r
  gBS->RestoreTPL (OldTpl);\r
  FreePool (VgpuGop->GopDevicePath);\r
\r
FreeVgpuGopName:\r
  FreeUnicodeStringTable (VgpuGop->GopName);\r
\r
FreeVgpuGop:\r
  FreePool (VgpuGop);\r
\r
  return Status;\r
}\r
\r
/**\r
  Tear down and release the VGPU_GOP child object within the VGPU_DEV parent\r
  object.\r
\r
  This function removes the BY_CHILD_CONTROLLER reference from\r
  ParentBusController's VIRTIO_DEVICE_PROTOCOL interface.\r
\r
  @param[in,out] ParentBus        The VGPU_DEV object that the VGPU_GOP child\r
                                  object will be removed from.\r
\r
  @param[in] ParentBusController  The UEFI controller handle on which the\r
                                  ParentBus VGPU_DEV object is installed.\r
\r
  @param[in] DriverBindingHandle  The DriverBindingHandle member of\r
                                  EFI_DRIVER_BINDING_PROTOCOL whose Stop()\r
                                  function is calling this function. It is\r
                                  passed as AgentHandle to gBS->CloseProtocol()\r
                                  when removing the BY_CHILD_CONTROLLER\r
                                  reference.\r
**/\r
STATIC\r
VOID\r
UninitVgpuGop (\r
  IN OUT VGPU_DEV   *ParentBus,\r
  IN     EFI_HANDLE ParentBusController,\r
  IN     EFI_HANDLE DriverBindingHandle\r
  )\r
{\r
  VGPU_GOP   *VgpuGop;\r
  EFI_STATUS Status;\r
\r
  VgpuGop = ParentBus->Child;\r
  Status = gBS->UninstallProtocolInterface (VgpuGop->GopHandle,\r
                  &gEfiGraphicsOutputProtocolGuid, &VgpuGop->Gop);\r
  ASSERT_EFI_ERROR (Status);\r
\r
  //\r
  // Uninitialize VgpuGop->Gop.\r
  //\r
  ReleaseGopResources (VgpuGop, TRUE /* DisableHead */);\r
\r
  Status = gBS->CloseProtocol (ParentBusController, &gVirtioDeviceProtocolGuid,\r
                  DriverBindingHandle, VgpuGop->GopHandle);\r
  ASSERT_EFI_ERROR (Status);\r
\r
  Status = gBS->UninstallProtocolInterface (VgpuGop->GopHandle,\r
                  &gEfiDevicePathProtocolGuid, VgpuGop->GopDevicePath);\r
  ASSERT_EFI_ERROR (Status);\r
\r
  FreePool (VgpuGop->GopDevicePath);\r
  FreeUnicodeStringTable (VgpuGop->GopName);\r
  FreePool (VgpuGop);\r
\r
  ParentBus->Child = NULL;\r
}\r
\r
//\r
// Driver Binding Protocol Implementation.\r
//\r
STATIC\r
EFI_STATUS\r
EFIAPI\r
VirtioGpuDriverBindingSupported (\r
  IN EFI_DRIVER_BINDING_PROTOCOL *This,\r
  IN EFI_HANDLE                  ControllerHandle,\r
  IN EFI_DEVICE_PATH_PROTOCOL    *RemainingDevicePath OPTIONAL\r
  )\r
{\r
  EFI_STATUS             Status;\r
  VIRTIO_DEVICE_PROTOCOL *VirtIo;\r
\r
  //\r
  // - If RemainingDevicePath is NULL: the caller is interested in creating all\r
  //   child handles.\r
  // - If RemainingDevicePath points to an end node: the caller is not\r
  //   interested in creating any child handle.\r
  // - Otherwise, the caller would like to create the one child handle\r
  //   specified in RemainingDevicePath. In this case we have to see if the\r
  //   requested device path is supportable.\r
  //\r
  if (RemainingDevicePath != NULL &&\r
      !IsDevicePathEnd (RemainingDevicePath) &&\r
      (DevicePathNodeLength (RemainingDevicePath) != sizeof mAcpiAdr ||\r
       CompareMem (RemainingDevicePath, &mAcpiAdr, sizeof mAcpiAdr) != 0)) {\r
    return EFI_UNSUPPORTED;\r
  }\r
\r
  //\r
  // Open the Virtio Device Protocol interface on the controller, BY_DRIVER.\r
  //\r
  Status = gBS->OpenProtocol (ControllerHandle, &gVirtioDeviceProtocolGuid,\r
                  (VOID **)&VirtIo, This->DriverBindingHandle,\r
                  ControllerHandle, EFI_OPEN_PROTOCOL_BY_DRIVER);\r
  if (EFI_ERROR (Status)) {\r
    //\r
    // If this fails, then by default we cannot support ControllerHandle. There\r
    // is one exception: we've already bound the device, have not produced any\r
    // GOP child controller, and now the caller wants us to produce the child\r
    // controller (either specifically or as part of "all children"). That's\r
    // allowed.\r
    //\r
    if (Status == EFI_ALREADY_STARTED) {\r
      EFI_STATUS Status2;\r
      VGPU_DEV   *VgpuDev;\r
\r
      Status2 = gBS->OpenProtocol (ControllerHandle, &gEfiCallerIdGuid,\r
                       (VOID **)&VgpuDev, This->DriverBindingHandle,\r
                       ControllerHandle, EFI_OPEN_PROTOCOL_GET_PROTOCOL);\r
      ASSERT_EFI_ERROR (Status2);\r
\r
      if (VgpuDev->Child == NULL &&\r
          (RemainingDevicePath == NULL ||\r
           !IsDevicePathEnd (RemainingDevicePath))) {\r
        Status = EFI_SUCCESS;\r
      }\r
    }\r
\r
    return Status;\r
  }\r
\r
  //\r
  // First BY_DRIVER open; check the VirtIo revision and subsystem.\r
  //\r
  if (VirtIo->Revision < VIRTIO_SPEC_REVISION (1, 0, 0) ||\r
      VirtIo->SubSystemDeviceId != VIRTIO_SUBSYSTEM_GPU_DEVICE) {\r
    Status = EFI_UNSUPPORTED;\r
    goto CloseVirtIo;\r
  }\r
\r
  //\r
  // We'll need the device path of the VirtIo device both for formatting\r
  // VGPU_DEV.BusName and for populating VGPU_GOP.GopDevicePath.\r
  //\r
  Status = gBS->OpenProtocol (ControllerHandle, &gEfiDevicePathProtocolGuid,\r
                  NULL, This->DriverBindingHandle, ControllerHandle,\r
                  EFI_OPEN_PROTOCOL_TEST_PROTOCOL);\r
\r
CloseVirtIo:\r
  gBS->CloseProtocol (ControllerHandle, &gVirtioDeviceProtocolGuid,\r
    This->DriverBindingHandle, ControllerHandle);\r
\r
  return Status;\r
}\r
\r
STATIC\r
EFI_STATUS\r
EFIAPI\r
VirtioGpuDriverBindingStart (\r
  IN EFI_DRIVER_BINDING_PROTOCOL *This,\r
  IN EFI_HANDLE                  ControllerHandle,\r
  IN EFI_DEVICE_PATH_PROTOCOL    *RemainingDevicePath OPTIONAL\r
  )\r
{\r
  EFI_STATUS               Status;\r
  VIRTIO_DEVICE_PROTOCOL   *VirtIo;\r
  BOOLEAN                  VirtIoBoundJustNow;\r
  VGPU_DEV                 *VgpuDev;\r
  EFI_DEVICE_PATH_PROTOCOL *DevicePath;\r
\r
  //\r
  // Open the Virtio Device Protocol.\r
  //\r
  // The result of this operation, combined with the checks in\r
  // VirtioGpuDriverBindingSupported(), uniquely tells us whether we are\r
  // binding the VirtIo controller on this call (with or without creating child\r
  // controllers), or else we're *only* creating child controllers.\r
  //\r
  Status = gBS->OpenProtocol (ControllerHandle, &gVirtioDeviceProtocolGuid,\r
                  (VOID **)&VirtIo, This->DriverBindingHandle,\r
                  ControllerHandle, EFI_OPEN_PROTOCOL_BY_DRIVER);\r
  if (EFI_ERROR (Status)) {\r
    //\r
    // The assertions below are based on the success of\r
    // VirtioGpuDriverBindingSupported(): we bound ControllerHandle earlier,\r
    // without producing child handles, and now we're producing the GOP child\r
    // handle only.\r
    //\r
    ASSERT (Status == EFI_ALREADY_STARTED);\r
\r
    Status = gBS->OpenProtocol (ControllerHandle, &gEfiCallerIdGuid,\r
                    (VOID **)&VgpuDev, This->DriverBindingHandle,\r
                    ControllerHandle, EFI_OPEN_PROTOCOL_GET_PROTOCOL);\r
    ASSERT_EFI_ERROR (Status);\r
\r
    ASSERT (VgpuDev->Child == NULL);\r
    ASSERT (\r
      RemainingDevicePath == NULL || !IsDevicePathEnd (RemainingDevicePath));\r
\r
    VirtIoBoundJustNow = FALSE;\r
  } else {\r
    VirtIoBoundJustNow = TRUE;\r
\r
    //\r
    // Allocate the private structure.\r
    //\r
    VgpuDev = AllocateZeroPool (sizeof *VgpuDev);\r
    if (VgpuDev == NULL) {\r
      Status = EFI_OUT_OF_RESOURCES;\r
      goto CloseVirtIo;\r
    }\r
    VgpuDev->VirtIo = VirtIo;\r
  }\r
\r
  //\r
  // Grab the VirtIo controller's device path. This is necessary regardless of\r
  // VirtIoBoundJustNow.\r
  //\r
  Status = gBS->OpenProtocol (ControllerHandle, &gEfiDevicePathProtocolGuid,\r
                  (VOID **)&DevicePath, This->DriverBindingHandle,\r
                  ControllerHandle, EFI_OPEN_PROTOCOL_GET_PROTOCOL);\r
  if (EFI_ERROR (Status)) {\r
    goto FreeVgpuDev;\r
  }\r
\r
  //\r
  // Create VGPU_DEV if we've bound the VirtIo controller right now (that is,\r
  // if we aren't *only* creating child handles).\r
  //\r
  if (VirtIoBoundJustNow) {\r
    CHAR16 *VgpuDevName;\r
\r
    //\r
    // Format a human-readable controller name for VGPU_DEV, and stash it for\r
    // VirtioGpuGetControllerName() to look up.\r
    //\r
    Status = FormatVgpuDevName (ControllerHandle, This->DriverBindingHandle,\r
               DevicePath, &VgpuDevName);\r
    if (EFI_ERROR (Status)) {\r
      goto FreeVgpuDev;\r
    }\r
    Status = AddUnicodeString2 ("en", mComponentName2.SupportedLanguages,\r
               &VgpuDev->BusName, VgpuDevName, FALSE /* Iso639Language */);\r
    FreePool (VgpuDevName);\r
    if (EFI_ERROR (Status)) {\r
      goto FreeVgpuDev;\r
    }\r
\r
    Status = VirtioGpuInit (VgpuDev);\r
    if (EFI_ERROR (Status)) {\r
      goto FreeVgpuDevBusName;\r
    }\r
\r
    Status = gBS->CreateEvent (EVT_SIGNAL_EXIT_BOOT_SERVICES, TPL_CALLBACK,\r
                    VirtioGpuExitBoot, VgpuDev /* NotifyContext */,\r
                    &VgpuDev->ExitBoot);\r
    if (EFI_ERROR (Status)) {\r
      goto UninitGpu;\r
    }\r
\r
    //\r
    // Install the VGPU_DEV "protocol interface" on ControllerHandle.\r
    //\r
    Status = gBS->InstallProtocolInterface (&ControllerHandle,\r
                    &gEfiCallerIdGuid, EFI_NATIVE_INTERFACE, VgpuDev);\r
    if (EFI_ERROR (Status)) {\r
      goto CloseExitBoot;\r
    }\r
\r
    if (RemainingDevicePath != NULL && IsDevicePathEnd (RemainingDevicePath)) {\r
      //\r
      // No child handle should be produced; we're done.\r
      //\r
      DEBUG ((EFI_D_INFO, "%a: bound VirtIo=%p without producing GOP\n",\r
        __FUNCTION__, (VOID *)VgpuDev->VirtIo));\r
      return EFI_SUCCESS;\r
    }\r
  }\r
\r
  //\r
  // Below we'll produce our single child handle: the caller requested it\r
  // either specifically, or as part of all child handles.\r
  //\r
  ASSERT (VgpuDev->Child == NULL);\r
  ASSERT (\r
    RemainingDevicePath == NULL || !IsDevicePathEnd (RemainingDevicePath));\r
\r
  Status = InitVgpuGop (VgpuDev, DevicePath, ControllerHandle,\r
             This->DriverBindingHandle);\r
  if (EFI_ERROR (Status)) {\r
    goto UninstallVgpuDev;\r
  }\r
\r
  //\r
  // We're done.\r
  //\r
  DEBUG ((EFI_D_INFO, "%a: produced GOP %a VirtIo=%p\n", __FUNCTION__,\r
    VirtIoBoundJustNow ? "while binding" : "for pre-bound",\r
    (VOID *)VgpuDev->VirtIo));\r
  return EFI_SUCCESS;\r
\r
UninstallVgpuDev:\r
  if (VirtIoBoundJustNow) {\r
    gBS->UninstallProtocolInterface (ControllerHandle, &gEfiCallerIdGuid,\r
           VgpuDev);\r
  }\r
\r
CloseExitBoot:\r
  if (VirtIoBoundJustNow) {\r
    gBS->CloseEvent (VgpuDev->ExitBoot);\r
  }\r
\r
UninitGpu:\r
  if (VirtIoBoundJustNow) {\r
    VirtioGpuUninit (VgpuDev);\r
  }\r
\r
FreeVgpuDevBusName:\r
  if (VirtIoBoundJustNow) {\r
    FreeUnicodeStringTable (VgpuDev->BusName);\r
  }\r
\r
FreeVgpuDev:\r
  if (VirtIoBoundJustNow) {\r
    FreePool (VgpuDev);\r
  }\r
\r
CloseVirtIo:\r
  if (VirtIoBoundJustNow) {\r
    gBS->CloseProtocol (ControllerHandle, &gVirtioDeviceProtocolGuid,\r
      This->DriverBindingHandle, ControllerHandle);\r
  }\r
\r
  return Status;\r
}\r
\r
STATIC\r
EFI_STATUS\r
EFIAPI\r
VirtioGpuDriverBindingStop (\r
  IN  EFI_DRIVER_BINDING_PROTOCOL *This,\r
  IN  EFI_HANDLE                  ControllerHandle,\r
  IN  UINTN                       NumberOfChildren,\r
  IN  EFI_HANDLE                  *ChildHandleBuffer OPTIONAL\r
  )\r
{\r
  EFI_STATUS Status;\r
  VGPU_DEV   *VgpuDev;\r
\r
  //\r
  // Look up the VGPU_DEV "protocol interface" on ControllerHandle.\r
  //\r
  Status = gBS->OpenProtocol (ControllerHandle, &gEfiCallerIdGuid,\r
                  (VOID **)&VgpuDev, This->DriverBindingHandle,\r
                  ControllerHandle, EFI_OPEN_PROTOCOL_GET_PROTOCOL);\r
  if (EFI_ERROR (Status)) {\r
    return Status;\r
  }\r
  //\r
  // Sanity check: if we found gEfiCallerIdGuid on ControllerHandle, then we\r
  // keep its Virtio Device Protocol interface open BY_DRIVER.\r
  //\r
  ASSERT_EFI_ERROR (EfiTestManagedDevice (ControllerHandle,\r
                      This->DriverBindingHandle, &gVirtioDeviceProtocolGuid));\r
\r
  switch (NumberOfChildren) {\r
  case 0:\r
    //\r
    // The caller wants us to unbind the VirtIo controller.\r
    //\r
    if (VgpuDev->Child != NULL) {\r
      //\r
      // We still have the GOP child.\r
      //\r
      Status = EFI_DEVICE_ERROR;\r
      break;\r
    }\r
\r
    DEBUG ((EFI_D_INFO, "%a: unbinding GOP-less VirtIo=%p\n", __FUNCTION__,\r
      (VOID *)VgpuDev->VirtIo));\r
\r
    Status = gBS->UninstallProtocolInterface (ControllerHandle,\r
                    &gEfiCallerIdGuid, VgpuDev);\r
    ASSERT_EFI_ERROR (Status);\r
\r
    Status = gBS->CloseEvent (VgpuDev->ExitBoot);\r
    ASSERT_EFI_ERROR (Status);\r
\r
    VirtioGpuUninit (VgpuDev);\r
    FreeUnicodeStringTable (VgpuDev->BusName);\r
    FreePool (VgpuDev);\r
\r
    Status = gBS->CloseProtocol (ControllerHandle, &gVirtioDeviceProtocolGuid,\r
                    This->DriverBindingHandle, ControllerHandle);\r
    ASSERT_EFI_ERROR (Status);\r
    break;\r
\r
  case 1:\r
    //\r
    // The caller wants us to destroy our child GOP controller.\r
    //\r
    if (VgpuDev->Child == NULL ||\r
        ChildHandleBuffer[0] != VgpuDev->Child->GopHandle) {\r
      //\r
      // We have no child controller at the moment, or it differs from the one\r
      // the caller wants us to destroy. I.e., we don't own the child\r
      // controller passed in.\r
      //\r
      Status = EFI_DEVICE_ERROR;\r
      break;\r
    }\r
    //\r
    // Sanity check: our GOP child controller keeps the VGPU_DEV controller's\r
    // Virtio Device Protocol interface open BY_CHILD_CONTROLLER.\r
    //\r
    ASSERT_EFI_ERROR (EfiTestChildHandle (ControllerHandle,\r
                        VgpuDev->Child->GopHandle,\r
                        &gVirtioDeviceProtocolGuid));\r
\r
    DEBUG ((EFI_D_INFO, "%a: destroying GOP under VirtIo=%p\n", __FUNCTION__,\r
      (VOID *)VgpuDev->VirtIo));\r
    UninitVgpuGop (VgpuDev, ControllerHandle, This->DriverBindingHandle);\r
    break;\r
\r
  default:\r
    //\r
    // Impossible, we never produced more than one child.\r
    //\r
    Status = EFI_DEVICE_ERROR;\r
    break;\r
  }\r
  return Status;\r
}\r
\r
STATIC EFI_DRIVER_BINDING_PROTOCOL mDriverBinding = {\r
  VirtioGpuDriverBindingSupported,\r
  VirtioGpuDriverBindingStart,\r
  VirtioGpuDriverBindingStop,\r
  0x10,                            // Version\r
  NULL,                            // ImageHandle, overwritten in entry point\r
  NULL                             // DriverBindingHandle, ditto\r
};\r
\r
//\r
// Entry point of the driver.\r
//\r
EFI_STATUS\r
EFIAPI\r
VirtioGpuEntryPoint (\r
  IN EFI_HANDLE       ImageHandle,\r
  IN EFI_SYSTEM_TABLE *SystemTable\r
  )\r
{\r
  return EfiLibInstallDriverBindingComponentName2 (ImageHandle, SystemTable,\r
           &mDriverBinding, ImageHandle, NULL /* ComponentName */,\r
           &mComponentName2);\r
}\r