OvmfPkg/XenBusDxe/XenBusDxe.c

   1 /** @file
   2   This driver produces XenBus Protocol instances for each Xen PV devices.
   3
   4   This XenBus bus driver will first initialize differente services in order to
   5   enumerate the ParaVirtualized devices available.
   6
   7   Those services are:
   8     - HyperCall
   9     - Event Channel
  10     - Grant Table
  11     - XenStore
  12     - XenBus
  13
  14   Copyright (C) 2014, Citrix Ltd.
  15
  16   This program and the accompanying materials
  17   are licensed and made available under the terms and conditions of the BSD License
  18   which accompanies this distribution.  The full text of the license may be found at
  19   http://opensource.org/licenses/bsd-license.php
  20
  21   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  22   WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  23
  24 **/
  25
  26 #include <IndustryStandard/Pci.h>
  27 #include <IndustryStandard/Acpi.h>
  28 #include <Library/DebugLib.h>
  29
  30 #include "XenBusDxe.h"
  31
  32
  33 ///
  34 /// Driver Binding Protocol instance
  35 ///
  36 EFI_DRIVER_BINDING_PROTOCOL gXenBusDxeDriverBinding = {
  37   XenBusDxeDriverBindingSupported,
  38   XenBusDxeDriverBindingStart,
  39   XenBusDxeDriverBindingStop,
  40   XENBUS_DXE_VERSION,
  41   NULL,
  42   NULL
  43 };
  44
  45
  46 /**
  47   Unloads an image.
  48
  49   @param  ImageHandle           Handle that identifies the image to be unloaded.
  50
  51   @retval EFI_SUCCESS           The image has been unloaded.
  52   @retval EFI_INVALID_PARAMETER ImageHandle is not a valid image handle.
  53
  54 **/
  55 EFI_STATUS
  56 EFIAPI
  57 XenBusDxeUnload (
  58   IN EFI_HANDLE  ImageHandle
  59   )
  60 {
  61   EFI_STATUS  Status;
  62
  63   EFI_HANDLE  *HandleBuffer;
  64   UINTN       HandleCount;
  65   UINTN       Index;
  66
  67   //
  68   // Retrieve array of all handles in the handle database
  69   //
  70   Status = gBS->LocateHandleBuffer (
  71                   AllHandles,
  72                   NULL,
  73                   NULL,
  74                   &HandleCount,
  75                   &HandleBuffer
  76                   );
  77   if (EFI_ERROR (Status)) {
  78     return Status;
  79   }
  80
  81   //
  82   // Disconnect the current driver from handles in the handle database
  83   //
  84   for (Index = 0; Index < HandleCount; Index++) {
  85     gBS->DisconnectController (HandleBuffer[Index], gImageHandle, NULL);
  86   }
  87
  88   //
  89   // Free the array of handles
  90   //
  91   FreePool (HandleBuffer);
  92
  93
  94   //
  95   // Uninstall protocols installed in the driver entry point
  96   //
  97   Status = gBS->UninstallMultipleProtocolInterfaces (
  98                   ImageHandle,
  99                   &gEfiDriverBindingProtocolGuid, &gXenBusDxeDriverBinding,
 100                   &gEfiComponentNameProtocolGuid,  &gXenBusDxeComponentName,
 101                   &gEfiComponentName2ProtocolGuid, &gXenBusDxeComponentName2,
 102                   NULL
 103                   );
 104   if (EFI_ERROR (Status)) {
 105     return Status;
 106   }
 107
 108   return EFI_SUCCESS;
 109 }
 110
 111 /**
 112   This is the declaration of an EFI image entry point. This entry point is
 113   the same for UEFI Applications, UEFI OS Loaders, and UEFI Drivers including
 114   both device drivers and bus drivers.
 115
 116   @param  ImageHandle           The firmware allocated handle for the UEFI image.
 117   @param  SystemTable           A pointer to the EFI System Table.
 118
 119   @retval EFI_SUCCESS           The operation completed successfully.
 120   @retval Others                An unexpected error occurred.
 121 **/
 122 EFI_STATUS
 123 EFIAPI
 124 XenBusDxeDriverEntryPoint (
 125   IN EFI_HANDLE        ImageHandle,
 126   IN EFI_SYSTEM_TABLE  *SystemTable
 127   )
 128 {
 129   EFI_STATUS  Status;
 130
 131   //
 132   // Install UEFI Driver Model protocol(s).
 133   //
 134   Status = EfiLibInstallDriverBindingComponentName2 (
 135              ImageHandle,
 136              SystemTable,
 137              &gXenBusDxeDriverBinding,
 138              ImageHandle,
 139              &gXenBusDxeComponentName,
 140              &gXenBusDxeComponentName2
 141              );
 142   ASSERT_EFI_ERROR (Status);
 143
 144
 145   return Status;
 146 }
 147
 148
 149 /**
 150   Tests to see if this driver supports a given controller. If a child device is provided,
 151   it further tests to see if this driver supports creating a handle for the specified child device.
 152
 153   @param[in]  This                 A pointer to the EFI_DRIVER_BINDING_PROTOCOL instance.
 154   @param[in]  ControllerHandle     The handle of the controller to test. This handle
 155                                    must support a protocol interface that supplies
 156                                    an I/O abstraction to the driver.
 157   @param[in]  RemainingDevicePath  A pointer to the remaining portion of a device path.  This
 158                                    parameter is ignored by device drivers, and is optional for bus
 159                                    drivers. For bus drivers, if this parameter is not NULL, then
 160                                    the bus driver must determine if the bus controller specified
 161                                    by ControllerHandle and the child controller specified
 162                                    by RemainingDevicePath are both supported by this
 163                                    bus driver.
 164
 165   @retval EFI_SUCCESS              The device specified by ControllerHandle and
 166                                    RemainingDevicePath is supported by the driver specified by This.
 167   @retval EFI_ALREADY_STARTED      The device specified by ControllerHandle and
 168                                    RemainingDevicePath is already being managed by the driver
 169                                    specified by This.
 170   @retval EFI_ACCESS_DENIED        The device specified by ControllerHandle and
 171                                    RemainingDevicePath is already being managed by a different
 172                                    driver or an application that requires exclusive access.
 173                                    Currently not implemented.
 174   @retval EFI_UNSUPPORTED          The device specified by ControllerHandle and
 175                                    RemainingDevicePath is not supported by the driver specified by This.
 176 **/
 177 EFI_STATUS
 178 EFIAPI
 179 XenBusDxeDriverBindingSupported (
 180   IN EFI_DRIVER_BINDING_PROTOCOL  *This,
 181   IN EFI_HANDLE                   ControllerHandle,
 182   IN EFI_DEVICE_PATH_PROTOCOL     *RemainingDevicePath OPTIONAL
 183   )
 184 {
 185   EFI_STATUS          Status;
 186   EFI_PCI_IO_PROTOCOL *PciIo;
 187   PCI_TYPE00          Pci;
 188
 189   Status = gBS->OpenProtocol (
 190                      ControllerHandle,
 191                      &gEfiPciIoProtocolGuid,
 192                      (VOID **)&PciIo,
 193                      This->DriverBindingHandle,
 194                      ControllerHandle,
 195                      EFI_OPEN_PROTOCOL_BY_DRIVER
 196                      );
 197   if (EFI_ERROR (Status)) {
 198     return Status;
 199   }
 200
 201   Status = PciIo->Pci.Read (PciIo, EfiPciIoWidthUint32, 0,
 202                             sizeof Pci / sizeof (UINT32), &Pci);
 203
 204   if (Status == EFI_SUCCESS) {
 205     if (Pci.Hdr.VendorId == PCI_VENDOR_ID_XEN &&
 206         Pci.Hdr.DeviceId == PCI_DEVICE_ID_XEN_PLATFORM) {
 207       Status = EFI_SUCCESS;
 208     } else {
 209       Status = EFI_UNSUPPORTED;
 210     }
 211   }
 212
 213   gBS->CloseProtocol (ControllerHandle, &gEfiPciIoProtocolGuid,
 214          This->DriverBindingHandle, ControllerHandle);
 215
 216   return Status;
 217 }
 218
 219 /**
 220   Starts a bus controller.
 221
 222   The Start() function is designed to be invoked from the EFI boot service ConnectController().
 223   As a result, much of the error checking on the parameters to Start() has been moved into this
 224   common boot service. It is legal to call Start() from other locations,
 225   but the following calling restrictions must be followed, or the system behavior will not be deterministic.
 226   1. ControllerHandle must be a valid EFI_HANDLE.
 227   2. If RemainingDevicePath is not NULL, then it must be a pointer to a naturally aligned
 228      EFI_DEVICE_PATH_PROTOCOL.
 229   3. Prior to calling Start(), the Supported() function for the driver specified by This must
 230      have been called with the same calling parameters, and Supported() must have returned EFI_SUCCESS.
 231
 232   @param[in]  This                 A pointer to the EFI_DRIVER_BINDING_PROTOCOL instance.
 233   @param[in]  ControllerHandle     The handle of the controller to start. This handle
 234                                    must support a protocol interface that supplies
 235                                    an I/O abstraction to the driver.
 236   @param[in]  RemainingDevicePath  A pointer to the remaining portion of a device path.  This
 237                                    parameter is ignored by device drivers, and is optional for bus
 238                                    drivers. For a bus driver, if this parameter is NULL, then handles
 239                                    for all the children of Controller are created by this driver.
 240                                    If this parameter is not NULL and the first Device Path Node is
 241                                    not the End of Device Path Node, then only the handle for the
 242                                    child device specified by the first Device Path Node of
 243                                    RemainingDevicePath is created by this driver.
 244                                    If the first Device Path Node of RemainingDevicePath is
 245                                    the End of Device Path Node, no child handle is created by this
 246                                    driver.
 247
 248   @retval EFI_SUCCESS              The device was started.
 249   @retval EFI_DEVICE_ERROR         The device could not be started due to a device error.Currently not implemented.
 250   @retval EFI_OUT_OF_RESOURCES     The request could not be completed due to a lack of resources.
 251   @retval Others                   The driver failded to start the device.
 252
 253 **/
 254 EFI_STATUS
 255 EFIAPI
 256 XenBusDxeDriverBindingStart (
 257   IN EFI_DRIVER_BINDING_PROTOCOL  *This,
 258   IN EFI_HANDLE                   ControllerHandle,
 259   IN EFI_DEVICE_PATH_PROTOCOL     *RemainingDevicePath OPTIONAL
 260   )
 261 {
 262   return EFI_UNSUPPORTED;
 263 }
 264
 265 /**
 266   Stops a bus controller.
 267
 268   The Stop() function is designed to be invoked from the EFI boot service DisconnectController().
 269   As a result, much of the error checking on the parameters to Stop() has been moved
 270   into this common boot service. It is legal to call Stop() from other locations,
 271   but the following calling restrictions must be followed, or the system behavior will not be deterministic.
 272   1. ControllerHandle must be a valid EFI_HANDLE that was used on a previous call to this
 273      same driver's Start() function.
 274   2. The first NumberOfChildren handles of ChildHandleBuffer must all be a valid
 275      EFI_HANDLE. In addition, all of these handles must have been created in this driver's
 276      Start() function, and the Start() function must have called OpenProtocol() on
 277      ControllerHandle with an Attribute of EFI_OPEN_PROTOCOL_BY_CHILD_CONTROLLER.
 278
 279   @param[in]  This              A pointer to the EFI_DRIVER_BINDING_PROTOCOL instance.
 280   @param[in]  ControllerHandle  A handle to the device being stopped. The handle must
 281                                 support a bus specific I/O protocol for the driver
 282                                 to use to stop the device.
 283   @param[in]  NumberOfChildren  The number of child device handles in ChildHandleBuffer.
 284   @param[in]  ChildHandleBuffer An array of child handles to be freed. May be NULL
 285                                 if NumberOfChildren is 0.
 286
 287   @retval EFI_SUCCESS           The device was stopped.
 288   @retval EFI_DEVICE_ERROR      The device could not be stopped due to a device error.
 289
 290 **/
 291 EFI_STATUS
 292 EFIAPI
 293 XenBusDxeDriverBindingStop (
 294   IN EFI_DRIVER_BINDING_PROTOCOL  *This,
 295   IN EFI_HANDLE                   ControllerHandle,
 296   IN UINTN                        NumberOfChildren,
 297   IN EFI_HANDLE                   *ChildHandleBuffer OPTIONAL
 298   )
 299 {
 300   return EFI_UNSUPPORTED;
 301 }