MdeModulePkg/Include/Protocol/Dpc.h

   1 /** @file
   2
   3   EFI Deferred Procedure Call Protocol.
   4
   5 Copyright (c) 2007 - 2018, Intel Corporation. All rights reserved.<BR>
   6 SPDX-License-Identifier: BSD-2-Clause-Patent
   7
   8 **/
   9
  10
  11 #ifndef __DPC_H__
  12 #define __DPC_H__
  13
  14 //
  15 // DPC Protocol GUID value
  16 //
  17 #define EFI_DPC_PROTOCOL_GUID \
  18     { \
  19       0x480f8ae9, 0xc46, 0x4aa9, { 0xbc, 0x89, 0xdb, 0x9f, 0xba, 0x61, 0x98, 0x6 } \
  20     }
  21
  22 //
  23 // Forward reference for pure ANSI compatability
  24 //
  25 typedef struct _EFI_DPC_PROTOCOL  EFI_DPC_PROTOCOL;
  26
  27
  28 /**
  29   Invoke a Deferred Procedure Call.
  30
  31   @param  DpcContext           The pointer to the Deferred Procedure Call's context,
  32                                which is implementation dependent.
  33
  34 **/
  35 typedef
  36 VOID
  37 (EFIAPI *EFI_DPC_PROCEDURE)(
  38   IN VOID  *DpcContext
  39   );
  40
  41 /**
  42   Add a Deferred Procedure Call to the end of the DPC queue.
  43
  44   @param  This          The protocol instance pointer.
  45   @param  DpcTpl        The EFI_TPL that the DPC should invoke.
  46   @param  DpcProcedure  The pointer to the DPC's function.
  47   @param  DpcContext    The pointer to the DPC's context.  Passed to DpcProcedure
  48                         when DpcProcedure is invoked.
  49
  50   @retval EFI_SUCCESS            The DPC was queued.
  51   @retval EFI_INVALID_PARAMETER  DpcTpl is not a valid EFI_TPL.
  52   @retval EFI_INVALID_PARAMETER  DpcProcedure is NULL.
  53   @retval EFI_OUT_OF_RESOURCES   There are not enough resources available to
  54                                  add the DPC to the queue.
  55
  56 **/
  57 typedef
  58 EFI_STATUS
  59 (EFIAPI *EFI_DPC_QUEUE_DPC)(
  60   IN EFI_DPC_PROTOCOL   *This,
  61   IN EFI_TPL            DpcTpl,
  62   IN EFI_DPC_PROCEDURE  DpcProcedure,
  63   IN VOID               *DpcContext    OPTIONAL
  64   );
  65
  66 /**
  67   Dispatch the queue of DPCs.
  68
  69   DPCs with DpcTpl value greater than the current TPL value are queued, and then DPCs
  70   with DpcTpl value lower than the current TPL value are queued. All DPCs in the first
  71   group (higher DpcTpl values) are invoked before DPCs in the second group (lower DpcTpl values).
  72
  73   @param  This  Protocol instance pointer.
  74
  75   @retval EFI_SUCCESS    One or more DPCs were invoked.
  76   @retval EFI_NOT_FOUND  No DPCs were invoked.
  77
  78 **/
  79 typedef
  80 EFI_STATUS
  81 (EFIAPI *EFI_DPC_DISPATCH_DPC)(
  82   IN EFI_DPC_PROTOCOL  *This
  83   );
  84
  85 ///
  86 /// DPC Protocol structure.
  87 ///
  88 struct _EFI_DPC_PROTOCOL {
  89   EFI_DPC_QUEUE_DPC     QueueDpc;
  90   EFI_DPC_DISPATCH_DPC  DispatchDpc;
  91 };
  92
  93 ///
  94 /// DPC Protocol GUID variable.
  95 ///
  96 extern EFI_GUID gEfiDpcProtocolGuid;
  97
  98 #endif