MdeModulePkg/Universal/Network/SnpDxe/WaitForPacket.c

   1 /** @file
   2     Event handler to check for available packet.
   3
   4 Copyright (c) 2004 - 2008, Intel Corporation. All rights reserved.<BR>
   5 This program and the accompanying materials are licensed
   6 and made available under the terms and conditions of the BSD License which
   7 accompanies this distribution. The full text of the license may be found at
   8 http://opensource.org/licenses/bsd-license.php
   9
  10 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  11 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  12
  13 **/
  14
  15 #include "Snp.h"
  16
  17
  18 /**
  19   Nofication call back function for WaitForPacket event.
  20
  21   @param  Event       EFI Event.
  22   @param  SnpPtr      Pointer to SNP_DRIVER structure.
  23
  24 **/
  25 VOID
  26 EFIAPI
  27 SnpWaitForPacketNotify (
  28   EFI_EVENT     Event,
  29   VOID          *SnpPtr
  30   )
  31 {
  32   PXE_DB_GET_STATUS PxeDbGetStatus;
  33
  34   //
  35   // Do nothing if either parameter is a NULL pointer.
  36   //
  37   if (Event == NULL || SnpPtr == NULL) {
  38     return ;
  39   }
  40   //
  41   // Do nothing if the SNP interface is not initialized.
  42   //
  43   switch (((SNP_DRIVER *) SnpPtr)->Mode.State) {
  44   case EfiSimpleNetworkInitialized:
  45     break;
  46
  47   case EfiSimpleNetworkStopped:
  48   case EfiSimpleNetworkStarted:
  49   default:
  50     return ;
  51   }
  52   //
  53   // Fill in CDB for UNDI GetStatus().
  54   //
  55   ((SNP_DRIVER *) SnpPtr)->Cdb.OpCode     = PXE_OPCODE_GET_STATUS;
  56   ((SNP_DRIVER *) SnpPtr)->Cdb.OpFlags    = 0;
  57   ((SNP_DRIVER *) SnpPtr)->Cdb.CPBsize    = PXE_CPBSIZE_NOT_USED;
  58   ((SNP_DRIVER *) SnpPtr)->Cdb.CPBaddr    = PXE_CPBADDR_NOT_USED;
  59   ((SNP_DRIVER *) SnpPtr)->Cdb.DBsize     = sizeof (UINT32) * 2;
  60   ((SNP_DRIVER *) SnpPtr)->Cdb.DBaddr     = (UINT64)(UINTN) (((SNP_DRIVER *) SnpPtr)->Db);
  61   ((SNP_DRIVER *) SnpPtr)->Cdb.StatCode   = PXE_STATCODE_INITIALIZE;
  62   ((SNP_DRIVER *) SnpPtr)->Cdb.StatFlags  = PXE_STATFLAGS_INITIALIZE;
  63   ((SNP_DRIVER *) SnpPtr)->Cdb.IFnum      = ((SNP_DRIVER *) SnpPtr)->IfNum;
  64   ((SNP_DRIVER *) SnpPtr)->Cdb.Control    = PXE_CONTROL_LAST_CDB_IN_LIST;
  65
  66   //
  67   // Clear contents of DB buffer.
  68   //
  69   ZeroMem (((SNP_DRIVER *) SnpPtr)->Db, sizeof (UINT32) * 2);
  70
  71   //
  72   // Issue UNDI command and check result.
  73   //
  74   (*((SNP_DRIVER *) SnpPtr)->IssueUndi32Command) ((UINT64)(UINTN) &((SNP_DRIVER *) SnpPtr)->Cdb);
  75
  76   if (((SNP_DRIVER *) SnpPtr)->Cdb.StatCode != EFI_SUCCESS) {
  77     return ;
  78   }
  79   //
  80   // We might have a packet.  Check the receive length and signal
  81   // the event if the length is not zero.
  82   //
  83   CopyMem (
  84     &PxeDbGetStatus,
  85     ((SNP_DRIVER *) SnpPtr)->Db,
  86     sizeof (UINT32) * 2
  87     );
  88
  89   if (PxeDbGetStatus.RxFrameLen != 0) {
  90     gBS->SignalEvent (Event);
  91   }
  92 }