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 #include "XenHypercall.h"
  33
  34
  35 ///
  36 /// Driver Binding Protocol instance
  37 ///
  38 EFI_DRIVER_BINDING_PROTOCOL gXenBusDxeDriverBinding = {
  39   XenBusDxeDriverBindingSupported,
  40   XenBusDxeDriverBindingStart,
  41   XenBusDxeDriverBindingStop,
  42   XENBUS_DXE_VERSION,
  43   NULL,
  44   NULL
  45 };
  46
  47
  48 STATIC EFI_LOCK       mMyDeviceLock = EFI_INITIALIZE_LOCK_VARIABLE (TPL_CALLBACK);
  49 STATIC XENBUS_DEVICE *mMyDevice = NULL;
  50
  51 /**
  52   Unloads an image.
  53
  54   @param  ImageHandle           Handle that identifies the image to be unloaded.
  55
  56   @retval EFI_SUCCESS           The image has been unloaded.
  57   @retval EFI_INVALID_PARAMETER ImageHandle is not a valid image handle.
  58
  59 **/
  60 EFI_STATUS
  61 EFIAPI
  62 XenBusDxeUnload (
  63   IN EFI_HANDLE  ImageHandle
  64   )
  65 {
  66   EFI_STATUS  Status;
  67
  68   EFI_HANDLE  *HandleBuffer;
  69   UINTN       HandleCount;
  70   UINTN       Index;
  71
  72   //
  73   // Retrieve array of all handles in the handle database
  74   //
  75   Status = gBS->LocateHandleBuffer (
  76                   AllHandles,
  77                   NULL,
  78                   NULL,
  79                   &HandleCount,
  80                   &HandleBuffer
  81                   );
  82   if (EFI_ERROR (Status)) {
  83     return Status;
  84   }
  85
  86   //
  87   // Disconnect the current driver from handles in the handle database
  88   //
  89   for (Index = 0; Index < HandleCount; Index++) {
  90     gBS->DisconnectController (HandleBuffer[Index], gImageHandle, NULL);
  91   }
  92
  93   //
  94   // Free the array of handles
  95   //
  96   FreePool (HandleBuffer);
  97
  98
  99   //
 100   // Uninstall protocols installed in the driver entry point
 101   //
 102   Status = gBS->UninstallMultipleProtocolInterfaces (
 103                   ImageHandle,
 104                   &gEfiDriverBindingProtocolGuid, &gXenBusDxeDriverBinding,
 105                   &gEfiComponentNameProtocolGuid,  &gXenBusDxeComponentName,
 106                   &gEfiComponentName2ProtocolGuid, &gXenBusDxeComponentName2,
 107                   NULL
 108                   );
 109   if (EFI_ERROR (Status)) {
 110     return Status;
 111   }
 112
 113   return EFI_SUCCESS;
 114 }
 115
 116 /**
 117   This is the declaration of an EFI image entry point. This entry point is
 118   the same for UEFI Applications, UEFI OS Loaders, and UEFI Drivers including
 119   both device drivers and bus drivers.
 120
 121   @param  ImageHandle           The firmware allocated handle for the UEFI image.
 122   @param  SystemTable           A pointer to the EFI System Table.
 123
 124   @retval EFI_SUCCESS           The operation completed successfully.
 125   @retval Others                An unexpected error occurred.
 126 **/
 127 EFI_STATUS
 128 EFIAPI
 129 XenBusDxeDriverEntryPoint (
 130   IN EFI_HANDLE        ImageHandle,
 131   IN EFI_SYSTEM_TABLE  *SystemTable
 132   )
 133 {
 134   EFI_STATUS  Status;
 135
 136   //
 137   // Install UEFI Driver Model protocol(s).
 138   //
 139   Status = EfiLibInstallDriverBindingComponentName2 (
 140              ImageHandle,
 141              SystemTable,
 142              &gXenBusDxeDriverBinding,
 143              ImageHandle,
 144              &gXenBusDxeComponentName,
 145              &gXenBusDxeComponentName2
 146              );
 147   ASSERT_EFI_ERROR (Status);
 148
 149
 150   return Status;
 151 }
 152
 153
 154 /**
 155   Tests to see if this driver supports a given controller. If a child device is provided,
 156   it further tests to see if this driver supports creating a handle for the specified child device.
 157
 158   @param[in]  This                 A pointer to the EFI_DRIVER_BINDING_PROTOCOL instance.
 159   @param[in]  ControllerHandle     The handle of the controller to test. This handle
 160                                    must support a protocol interface that supplies
 161                                    an I/O abstraction to the driver.
 162   @param[in]  RemainingDevicePath  A pointer to the remaining portion of a device path.  This
 163                                    parameter is ignored by device drivers, and is optional for bus
 164                                    drivers. For bus drivers, if this parameter is not NULL, then
 165                                    the bus driver must determine if the bus controller specified
 166                                    by ControllerHandle and the child controller specified
 167                                    by RemainingDevicePath are both supported by this
 168                                    bus driver.
 169
 170   @retval EFI_SUCCESS              The device specified by ControllerHandle and
 171                                    RemainingDevicePath is supported by the driver specified by This.
 172   @retval EFI_ALREADY_STARTED      The device specified by ControllerHandle and
 173                                    RemainingDevicePath is already being managed by the driver
 174                                    specified by This.
 175   @retval EFI_ACCESS_DENIED        The device specified by ControllerHandle and
 176                                    RemainingDevicePath is already being managed by a different
 177                                    driver or an application that requires exclusive access.
 178                                    Currently not implemented.
 179   @retval EFI_UNSUPPORTED          The device specified by ControllerHandle and
 180                                    RemainingDevicePath is not supported by the driver specified by This.
 181 **/
 182 EFI_STATUS
 183 EFIAPI
 184 XenBusDxeDriverBindingSupported (
 185   IN EFI_DRIVER_BINDING_PROTOCOL  *This,
 186   IN EFI_HANDLE                   ControllerHandle,
 187   IN EFI_DEVICE_PATH_PROTOCOL     *RemainingDevicePath OPTIONAL
 188   )
 189 {
 190   EFI_STATUS          Status;
 191   EFI_PCI_IO_PROTOCOL *PciIo;
 192   PCI_TYPE00          Pci;
 193
 194   Status = gBS->OpenProtocol (
 195                      ControllerHandle,
 196                      &gEfiPciIoProtocolGuid,
 197                      (VOID **)&PciIo,
 198                      This->DriverBindingHandle,
 199                      ControllerHandle,
 200                      EFI_OPEN_PROTOCOL_BY_DRIVER
 201                      );
 202   if (EFI_ERROR (Status)) {
 203     return Status;
 204   }
 205
 206   Status = PciIo->Pci.Read (PciIo, EfiPciIoWidthUint32, 0,
 207                             sizeof Pci / sizeof (UINT32), &Pci);
 208
 209   if (Status == EFI_SUCCESS) {
 210     if (Pci.Hdr.VendorId == PCI_VENDOR_ID_XEN &&
 211         Pci.Hdr.DeviceId == PCI_DEVICE_ID_XEN_PLATFORM) {
 212       Status = EFI_SUCCESS;
 213     } else {
 214       Status = EFI_UNSUPPORTED;
 215     }
 216   }
 217
 218   gBS->CloseProtocol (ControllerHandle, &gEfiPciIoProtocolGuid,
 219          This->DriverBindingHandle, ControllerHandle);
 220
 221   return Status;
 222 }
 223
 224 VOID
 225 EFIAPI
 226 NotifyExitBoot (
 227   IN EFI_EVENT Event,
 228   IN VOID *Context
 229   )
 230 {
 231   XENBUS_DEVICE *Dev = Context;
 232
 233   gBS->DisconnectController(Dev->ControllerHandle,
 234                             Dev->This->DriverBindingHandle, NULL);
 235 }
 236
 237 /**
 238   Starts a bus controller.
 239
 240   The Start() function is designed to be invoked from the EFI boot service ConnectController().
 241   As a result, much of the error checking on the parameters to Start() has been moved into this
 242   common boot service. It is legal to call Start() from other locations,
 243   but the following calling restrictions must be followed, or the system behavior will not be deterministic.
 244   1. ControllerHandle must be a valid EFI_HANDLE.
 245   2. If RemainingDevicePath is not NULL, then it must be a pointer to a naturally aligned
 246      EFI_DEVICE_PATH_PROTOCOL.
 247   3. Prior to calling Start(), the Supported() function for the driver specified by This must
 248      have been called with the same calling parameters, and Supported() must have returned EFI_SUCCESS.
 249
 250   @param[in]  This                 A pointer to the EFI_DRIVER_BINDING_PROTOCOL instance.
 251   @param[in]  ControllerHandle     The handle of the controller to start. This handle
 252                                    must support a protocol interface that supplies
 253                                    an I/O abstraction to the driver.
 254   @param[in]  RemainingDevicePath  A pointer to the remaining portion of a device path.  This
 255                                    parameter is ignored by device drivers, and is optional for bus
 256                                    drivers. For a bus driver, if this parameter is NULL, then handles
 257                                    for all the children of Controller are created by this driver.
 258                                    If this parameter is not NULL and the first Device Path Node is
 259                                    not the End of Device Path Node, then only the handle for the
 260                                    child device specified by the first Device Path Node of
 261                                    RemainingDevicePath is created by this driver.
 262                                    If the first Device Path Node of RemainingDevicePath is
 263                                    the End of Device Path Node, no child handle is created by this
 264                                    driver.
 265
 266   @retval EFI_SUCCESS              The device was started.
 267   @retval EFI_DEVICE_ERROR         The device could not be started due to a device error.Currently not implemented.
 268   @retval EFI_OUT_OF_RESOURCES     The request could not be completed due to a lack of resources.
 269   @retval EFI_UNSUPPORTED          Something is missing on the system that
 270                                    prevent to start the edvice.
 271   @retval Others                   The driver failded to start the device.
 272
 273 **/
 274 EFI_STATUS
 275 EFIAPI
 276 XenBusDxeDriverBindingStart (
 277   IN EFI_DRIVER_BINDING_PROTOCOL  *This,
 278   IN EFI_HANDLE                   ControllerHandle,
 279   IN EFI_DEVICE_PATH_PROTOCOL     *RemainingDevicePath OPTIONAL
 280   )
 281 {
 282   EFI_STATUS Status;
 283   XENBUS_DEVICE *Dev;
 284
 285   Dev = AllocateZeroPool (sizeof (*Dev));
 286   Dev->Signature = XENBUS_DEVICE_SIGNATURE;
 287   Dev->This = This;
 288   Dev->ControllerHandle = ControllerHandle;
 289
 290   EfiAcquireLock (&mMyDeviceLock);
 291   if (mMyDevice != NULL) {
 292     EfiReleaseLock (&mMyDeviceLock);
 293     //
 294     // There is already a XenBus running, only one can be used at a time.
 295     //
 296     Status = EFI_ALREADY_STARTED;
 297     goto ErrorAllocated;
 298   }
 299   mMyDevice = Dev;
 300   EfiReleaseLock (&mMyDeviceLock);
 301
 302   Status = XenHyperpageInit (Dev);
 303   if (EFI_ERROR (Status)) {
 304     DEBUG ((EFI_D_ERROR, "XenBus: Unable to retrieve the hyperpage.\n"));
 305     Status = EFI_UNSUPPORTED;
 306     goto ErrorAllocated;
 307   }
 308
 309   Status = XenGetSharedInfoPage (Dev);
 310   if (EFI_ERROR (Status)) {
 311     DEBUG ((EFI_D_ERROR, "XenBus: Unable to get the shared info page.\n"));
 312     Status = EFI_UNSUPPORTED;
 313     goto ErrorAllocated;
 314   }
 315
 316   Status = gBS->CreateEvent (EVT_SIGNAL_EXIT_BOOT_SERVICES, TPL_CALLBACK,
 317                              NotifyExitBoot,
 318                              (VOID*) Dev,
 319                              &Dev->ExitBootEvent);
 320   ASSERT_EFI_ERROR (Status);
 321
 322   return EFI_SUCCESS;
 323
 324 ErrorAllocated:
 325   FreePool (Dev);
 326   return Status;
 327 }
 328
 329 /**
 330   Stops a bus controller.
 331
 332   The Stop() function is designed to be invoked from the EFI boot service DisconnectController().
 333   As a result, much of the error checking on the parameters to Stop() has been moved
 334   into this common boot service. It is legal to call Stop() from other locations,
 335   but the following calling restrictions must be followed, or the system behavior will not be deterministic.
 336   1. ControllerHandle must be a valid EFI_HANDLE that was used on a previous call to this
 337      same driver's Start() function.
 338   2. The first NumberOfChildren handles of ChildHandleBuffer must all be a valid
 339      EFI_HANDLE. In addition, all of these handles must have been created in this driver's
 340      Start() function, and the Start() function must have called OpenProtocol() on
 341      ControllerHandle with an Attribute of EFI_OPEN_PROTOCOL_BY_CHILD_CONTROLLER.
 342
 343   @param[in]  This              A pointer to the EFI_DRIVER_BINDING_PROTOCOL instance.
 344   @param[in]  ControllerHandle  A handle to the device being stopped. The handle must
 345                                 support a bus specific I/O protocol for the driver
 346                                 to use to stop the device.
 347   @param[in]  NumberOfChildren  The number of child device handles in ChildHandleBuffer.
 348   @param[in]  ChildHandleBuffer An array of child handles to be freed. May be NULL
 349                                 if NumberOfChildren is 0.
 350
 351   @retval EFI_SUCCESS           The device was stopped.
 352   @retval EFI_DEVICE_ERROR      The device could not be stopped due to a device error.
 353
 354 **/
 355 EFI_STATUS
 356 EFIAPI
 357 XenBusDxeDriverBindingStop (
 358   IN EFI_DRIVER_BINDING_PROTOCOL  *This,
 359   IN EFI_HANDLE                   ControllerHandle,
 360   IN UINTN                        NumberOfChildren,
 361   IN EFI_HANDLE                   *ChildHandleBuffer OPTIONAL
 362   )
 363 {
 364   XENBUS_DEVICE *Dev = mMyDevice;
 365
 366   gBS->CloseEvent (Dev->ExitBootEvent);
 367
 368   mMyDevice = NULL;
 369   FreePool (Dev);
 370   return EFI_SUCCESS;
 371 }