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 STATIC EFI_LOCK       mMyDeviceLock = EFI_INITIALIZE_LOCK_VARIABLE (TPL_CALLBACK);
  47 STATIC XENBUS_DEVICE *mMyDevice = NULL;
  48
  49 /**
  50   Unloads an image.
  51
  52   @param  ImageHandle           Handle that identifies the image to be unloaded.
  53
  54   @retval EFI_SUCCESS           The image has been unloaded.
  55   @retval EFI_INVALID_PARAMETER ImageHandle is not a valid image handle.
  56
  57 **/
  58 EFI_STATUS
  59 EFIAPI
  60 XenBusDxeUnload (
  61   IN EFI_HANDLE  ImageHandle
  62   )
  63 {
  64   EFI_STATUS  Status;
  65
  66   EFI_HANDLE  *HandleBuffer;
  67   UINTN       HandleCount;
  68   UINTN       Index;
  69
  70   //
  71   // Retrieve array of all handles in the handle database
  72   //
  73   Status = gBS->LocateHandleBuffer (
  74                   AllHandles,
  75                   NULL,
  76                   NULL,
  77                   &HandleCount,
  78                   &HandleBuffer
  79                   );
  80   if (EFI_ERROR (Status)) {
  81     return Status;
  82   }
  83
  84   //
  85   // Disconnect the current driver from handles in the handle database
  86   //
  87   for (Index = 0; Index < HandleCount; Index++) {
  88     gBS->DisconnectController (HandleBuffer[Index], gImageHandle, NULL);
  89   }
  90
  91   //
  92   // Free the array of handles
  93   //
  94   FreePool (HandleBuffer);
  95
  96
  97   //
  98   // Uninstall protocols installed in the driver entry point
  99   //
 100   Status = gBS->UninstallMultipleProtocolInterfaces (
 101                   ImageHandle,
 102                   &gEfiDriverBindingProtocolGuid, &gXenBusDxeDriverBinding,
 103                   &gEfiComponentNameProtocolGuid,  &gXenBusDxeComponentName,
 104                   &gEfiComponentName2ProtocolGuid, &gXenBusDxeComponentName2,
 105                   NULL
 106                   );
 107   if (EFI_ERROR (Status)) {
 108     return Status;
 109   }
 110
 111   return EFI_SUCCESS;
 112 }
 113
 114 /**
 115   This is the declaration of an EFI image entry point. This entry point is
 116   the same for UEFI Applications, UEFI OS Loaders, and UEFI Drivers including
 117   both device drivers and bus drivers.
 118
 119   @param  ImageHandle           The firmware allocated handle for the UEFI image.
 120   @param  SystemTable           A pointer to the EFI System Table.
 121
 122   @retval EFI_SUCCESS           The operation completed successfully.
 123   @retval Others                An unexpected error occurred.
 124 **/
 125 EFI_STATUS
 126 EFIAPI
 127 XenBusDxeDriverEntryPoint (
 128   IN EFI_HANDLE        ImageHandle,
 129   IN EFI_SYSTEM_TABLE  *SystemTable
 130   )
 131 {
 132   EFI_STATUS  Status;
 133
 134   //
 135   // Install UEFI Driver Model protocol(s).
 136   //
 137   Status = EfiLibInstallDriverBindingComponentName2 (
 138              ImageHandle,
 139              SystemTable,
 140              &gXenBusDxeDriverBinding,
 141              ImageHandle,
 142              &gXenBusDxeComponentName,
 143              &gXenBusDxeComponentName2
 144              );
 145   ASSERT_EFI_ERROR (Status);
 146
 147
 148   return Status;
 149 }
 150
 151
 152 /**
 153   Tests to see if this driver supports a given controller. If a child device is provided,
 154   it further tests to see if this driver supports creating a handle for the specified child device.
 155
 156   @param[in]  This                 A pointer to the EFI_DRIVER_BINDING_PROTOCOL instance.
 157   @param[in]  ControllerHandle     The handle of the controller to test. This handle
 158                                    must support a protocol interface that supplies
 159                                    an I/O abstraction to the driver.
 160   @param[in]  RemainingDevicePath  A pointer to the remaining portion of a device path.  This
 161                                    parameter is ignored by device drivers, and is optional for bus
 162                                    drivers. For bus drivers, if this parameter is not NULL, then
 163                                    the bus driver must determine if the bus controller specified
 164                                    by ControllerHandle and the child controller specified
 165                                    by RemainingDevicePath are both supported by this
 166                                    bus driver.
 167
 168   @retval EFI_SUCCESS              The device specified by ControllerHandle and
 169                                    RemainingDevicePath is supported by the driver specified by This.
 170   @retval EFI_ALREADY_STARTED      The device specified by ControllerHandle and
 171                                    RemainingDevicePath is already being managed by the driver
 172                                    specified by This.
 173   @retval EFI_ACCESS_DENIED        The device specified by ControllerHandle and
 174                                    RemainingDevicePath is already being managed by a different
 175                                    driver or an application that requires exclusive access.
 176                                    Currently not implemented.
 177   @retval EFI_UNSUPPORTED          The device specified by ControllerHandle and
 178                                    RemainingDevicePath is not supported by the driver specified by This.
 179 **/
 180 EFI_STATUS
 181 EFIAPI
 182 XenBusDxeDriverBindingSupported (
 183   IN EFI_DRIVER_BINDING_PROTOCOL  *This,
 184   IN EFI_HANDLE                   ControllerHandle,
 185   IN EFI_DEVICE_PATH_PROTOCOL     *RemainingDevicePath OPTIONAL
 186   )
 187 {
 188   EFI_STATUS          Status;
 189   EFI_PCI_IO_PROTOCOL *PciIo;
 190   PCI_TYPE00          Pci;
 191
 192   Status = gBS->OpenProtocol (
 193                      ControllerHandle,
 194                      &gEfiPciIoProtocolGuid,
 195                      (VOID **)&PciIo,
 196                      This->DriverBindingHandle,
 197                      ControllerHandle,
 198                      EFI_OPEN_PROTOCOL_BY_DRIVER
 199                      );
 200   if (EFI_ERROR (Status)) {
 201     return Status;
 202   }
 203
 204   Status = PciIo->Pci.Read (PciIo, EfiPciIoWidthUint32, 0,
 205                             sizeof Pci / sizeof (UINT32), &Pci);
 206
 207   if (Status == EFI_SUCCESS) {
 208     if (Pci.Hdr.VendorId == PCI_VENDOR_ID_XEN &&
 209         Pci.Hdr.DeviceId == PCI_DEVICE_ID_XEN_PLATFORM) {
 210       Status = EFI_SUCCESS;
 211     } else {
 212       Status = EFI_UNSUPPORTED;
 213     }
 214   }
 215
 216   gBS->CloseProtocol (ControllerHandle, &gEfiPciIoProtocolGuid,
 217          This->DriverBindingHandle, ControllerHandle);
 218
 219   return Status;
 220 }
 221
 222 VOID
 223 EFIAPI
 224 NotifyExitBoot (
 225   IN EFI_EVENT Event,
 226   IN VOID *Context
 227   )
 228 {
 229   XENBUS_DEVICE *Dev = Context;
 230
 231   gBS->DisconnectController(Dev->ControllerHandle,
 232                             Dev->This->DriverBindingHandle, NULL);
 233 }
 234
 235 /**
 236   Starts a bus controller.
 237
 238   The Start() function is designed to be invoked from the EFI boot service ConnectController().
 239   As a result, much of the error checking on the parameters to Start() has been moved into this
 240   common boot service. It is legal to call Start() from other locations,
 241   but the following calling restrictions must be followed, or the system behavior will not be deterministic.
 242   1. ControllerHandle must be a valid EFI_HANDLE.
 243   2. If RemainingDevicePath is not NULL, then it must be a pointer to a naturally aligned
 244      EFI_DEVICE_PATH_PROTOCOL.
 245   3. Prior to calling Start(), the Supported() function for the driver specified by This must
 246      have been called with the same calling parameters, and Supported() must have returned EFI_SUCCESS.
 247
 248   @param[in]  This                 A pointer to the EFI_DRIVER_BINDING_PROTOCOL instance.
 249   @param[in]  ControllerHandle     The handle of the controller to start. This handle
 250                                    must support a protocol interface that supplies
 251                                    an I/O abstraction to the driver.
 252   @param[in]  RemainingDevicePath  A pointer to the remaining portion of a device path.  This
 253                                    parameter is ignored by device drivers, and is optional for bus
 254                                    drivers. For a bus driver, if this parameter is NULL, then handles
 255                                    for all the children of Controller are created by this driver.
 256                                    If this parameter is not NULL and the first Device Path Node is
 257                                    not the End of Device Path Node, then only the handle for the
 258                                    child device specified by the first Device Path Node of
 259                                    RemainingDevicePath is created by this driver.
 260                                    If the first Device Path Node of RemainingDevicePath is
 261                                    the End of Device Path Node, no child handle is created by this
 262                                    driver.
 263
 264   @retval EFI_SUCCESS              The device was started.
 265   @retval EFI_DEVICE_ERROR         The device could not be started due to a device error.Currently not implemented.
 266   @retval EFI_OUT_OF_RESOURCES     The request could not be completed due to a lack of resources.
 267   @retval Others                   The driver failded to start the device.
 268
 269 **/
 270 EFI_STATUS
 271 EFIAPI
 272 XenBusDxeDriverBindingStart (
 273   IN EFI_DRIVER_BINDING_PROTOCOL  *This,
 274   IN EFI_HANDLE                   ControllerHandle,
 275   IN EFI_DEVICE_PATH_PROTOCOL     *RemainingDevicePath OPTIONAL
 276   )
 277 {
 278   EFI_STATUS Status;
 279   XENBUS_DEVICE *Dev;
 280
 281   Dev = AllocateZeroPool (sizeof (*Dev));
 282   Dev->Signature = XENBUS_DEVICE_SIGNATURE;
 283   Dev->This = This;
 284   Dev->ControllerHandle = ControllerHandle;
 285
 286   EfiAcquireLock (&mMyDeviceLock);
 287   if (mMyDevice != NULL) {
 288     EfiReleaseLock (&mMyDeviceLock);
 289     //
 290     // There is already a XenBus running, only one can be used at a time.
 291     //
 292     Status = EFI_ALREADY_STARTED;
 293     goto ErrorAllocated;
 294   }
 295   mMyDevice = Dev;
 296   EfiReleaseLock (&mMyDeviceLock);
 297
 298   Status = gBS->CreateEvent (EVT_SIGNAL_EXIT_BOOT_SERVICES, TPL_CALLBACK,
 299                              NotifyExitBoot,
 300                              (VOID*) Dev,
 301                              &Dev->ExitBootEvent);
 302   ASSERT_EFI_ERROR (Status);
 303
 304   return EFI_SUCCESS;
 305
 306 ErrorAllocated:
 307   FreePool (Dev);
 308   return Status;
 309 }
 310
 311 /**
 312   Stops a bus controller.
 313
 314   The Stop() function is designed to be invoked from the EFI boot service DisconnectController().
 315   As a result, much of the error checking on the parameters to Stop() has been moved
 316   into this common boot service. It is legal to call Stop() from other locations,
 317   but the following calling restrictions must be followed, or the system behavior will not be deterministic.
 318   1. ControllerHandle must be a valid EFI_HANDLE that was used on a previous call to this
 319      same driver's Start() function.
 320   2. The first NumberOfChildren handles of ChildHandleBuffer must all be a valid
 321      EFI_HANDLE. In addition, all of these handles must have been created in this driver's
 322      Start() function, and the Start() function must have called OpenProtocol() on
 323      ControllerHandle with an Attribute of EFI_OPEN_PROTOCOL_BY_CHILD_CONTROLLER.
 324
 325   @param[in]  This              A pointer to the EFI_DRIVER_BINDING_PROTOCOL instance.
 326   @param[in]  ControllerHandle  A handle to the device being stopped. The handle must
 327                                 support a bus specific I/O protocol for the driver
 328                                 to use to stop the device.
 329   @param[in]  NumberOfChildren  The number of child device handles in ChildHandleBuffer.
 330   @param[in]  ChildHandleBuffer An array of child handles to be freed. May be NULL
 331                                 if NumberOfChildren is 0.
 332
 333   @retval EFI_SUCCESS           The device was stopped.
 334   @retval EFI_DEVICE_ERROR      The device could not be stopped due to a device error.
 335
 336 **/
 337 EFI_STATUS
 338 EFIAPI
 339 XenBusDxeDriverBindingStop (
 340   IN EFI_DRIVER_BINDING_PROTOCOL  *This,
 341   IN EFI_HANDLE                   ControllerHandle,
 342   IN UINTN                        NumberOfChildren,
 343   IN EFI_HANDLE                   *ChildHandleBuffer OPTIONAL
 344   )
 345 {
 346   XENBUS_DEVICE *Dev = mMyDevice;
 347
 348   gBS->CloseEvent (Dev->ExitBootEvent);
 349
 350   mMyDevice = NULL;
 351   FreePool (Dev);
 352   return EFI_SUCCESS;
 353 }