MdePkg/Include/Protocol/Bds.h

   1 /** @file
   2   Boot Device Selection Architectural Protocol as defined in DXE CIS
   3
   4   When the DXE core is done it calls the BDS via this protocol.
   5
   6   Copyright (c) 2006, Intel Corporation
   7   All rights reserved. This program and the accompanying materials
   8   are licensed and made available under the terms and conditions of the BSD License
   9   which accompanies this distribution.  The full text of the license may be found at
  10   http://opensource.org/licenses/bsd-license.php
  11
  12   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  13   WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  14
  15   @par Revision Reference:
  16   Version 0.91B.
  17
  18 **/
  19
  20 #ifndef __ARCH_PROTOCOL_BDS_H__
  21 #define __ARCH_PROTOCOL_BDS_H__
  22
  23 //
  24 // Global ID for the BDS Architectural Protocol
  25 //
  26 #define EFI_BDS_ARCH_PROTOCOL_GUID \
  27   { 0x665E3FF6, 0x46CC, 0x11d4, {0x9A, 0x38, 0x00, 0x90, 0x27, 0x3F, 0xC1, 0x4D } }
  28
  29 //
  30 // Declare forward reference for the BDS Architectural Protocol
  31 //
  32 typedef struct _EFI_BDS_ARCH_PROTOCOL   EFI_BDS_ARCH_PROTOCOL;
  33
  34 /**
  35   This function uses policy data from the platform to determine what operating
  36   system or system utility should be loaded and invoked.  This function call
  37   also optionally make the use of user input to determine the operating system
  38   or system utility to be loaded and invoked.  When the DXE Core has dispatched
  39   all the drivers on the dispatch queue, this function is called.  This
  40   function will attempt to connect the boot devices required to load and invoke
  41   the selected operating system or system utility.  During this process,
  42   additional firmware volumes may be discovered that may contain addition DXE
  43   drivers that can be dispatched by the DXE Core.   If a boot device cannot be
  44   fully connected, this function calls the DXE Service Dispatch() to allow the
  45   DXE drivers from any newly discovered firmware volumes to be dispatched.
  46   Then the boot device connection can be attempted again.  If the same boot
  47   device connection operation fails twice in a row, then that boot device has
  48   failed, and should be skipped.  This function should never return.
  49
  50   @param  This             The EFI_BDS_ARCH_PROTOCOL instance.
  51
  52   @return None.
  53
  54 **/
  55 typedef
  56 VOID
  57 (EFIAPI *EFI_BDS_ENTRY) (
  58   IN EFI_BDS_ARCH_PROTOCOL  *This
  59   );
  60
  61 /**
  62   Interface stucture for the BDS Architectural Protocol.
  63
  64   @par Protocol Description:
  65   The EFI_BDS_ARCH_PROTOCOL transfers control from DXE to an operating
  66   system or a system utility.  If there are not enough drivers initialized
  67   when this protocol is used to access the required boot device(s), then
  68   this protocol should add drivers to the dispatch queue and return control
  69   back to the dispatcher.  Once the required boot devices are available, then
  70   the boot device can be used to load and invoke an OS or a system utility.
  71
  72   @par Protocol Parameters:
  73   Entry - The entry point to BDS.  This call does not take any parameters,
  74   and the return value can be ignored.  If it returns, then the
  75   dispatcher must be invoked again, if it never returns, then an
  76   operating system or a system utility have been invoked.
  77
  78 **/
  79 struct _EFI_BDS_ARCH_PROTOCOL {
  80   EFI_BDS_ENTRY Entry;
  81 };
  82
  83 extern EFI_GUID gEfiBdsArchProtocolGuid;
  84
  85 #endif