InOsEmuPkg/Library/PeiEmuSerialPortLib/PeiEmuSerialPortLib.c

   1 /** @file
   2   Serial Port Lib that thunks back to Emulator services to write to StdErr.
   3   All read functions are stubed out. There is no constructor so this lib can
   4   be linked with PEI Core.
   5
   6   Copyright (c) 2006 - 2010, Intel Corporation. All rights reserved.<BR>
   7   Portions copyright (c) 2011, Apple Inc. All rights reserved.<BR>
   8   This program and the accompanying materials
   9   are licensed and made available under the terms and conditions of the BSD License
  10   which accompanies this distribution.  The full text of the license may be found at
  11   http://opensource.org/licenses/bsd-license.php.
  12
  13   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  14   WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  15
  16 **/
  17
  18
  19 #include <PiPei.h>
  20 #include <Library/SerialPortLib.h>
  21 #include <Library/PeiServicesLib.h>
  22
  23 #include <Ppi/EmuThunk.h>
  24 #include <Protocol/EmuThunk.h>
  25
  26
  27
  28 /**
  29   Initialize the serial device hardware.
  30
  31   If no initialization is required, then return RETURN_SUCCESS.
  32   If the serial device was successfully initialized, then return RETURN_SUCCESS.
  33   If the serial device could not be initialized, then return RETURN_DEVICE_ERROR.
  34
  35   @retval RETURN_SUCCESS        The serial device was initialized.
  36   @retval RETURN_DEVICE_ERROR   The serial device could not be initialized.
  37
  38 **/
  39 RETURN_STATUS
  40 EFIAPI
  41 SerialPortInitialize (
  42   VOID
  43   )
  44 {
  45   return RETURN_SUCCESS;
  46 }
  47
  48 /**
  49   Write data from buffer to serial device.
  50
  51   Writes NumberOfBytes data bytes from Buffer to the serial device.
  52   The number of bytes actually written to the serial device is returned.
  53   If the return value is less than NumberOfBytes, then the write operation failed.
  54   If Buffer is NULL, then ASSERT().
  55   If NumberOfBytes is zero, then return 0.
  56
  57   @param  Buffer           The pointer to the data buffer to be written.
  58   @param  NumberOfBytes    The number of bytes to written to the serial device.
  59
  60   @retval 0                NumberOfBytes is 0.
  61   @retval >0               The number of bytes written to the serial device.
  62                            If this value is less than NumberOfBytes, then the read operation failed.
  63
  64 **/
  65 UINTN
  66 EFIAPI
  67 SerialPortWrite (
  68   IN UINT8     *Buffer,
  69   IN UINTN     NumberOfBytes
  70   )
  71 {
  72   EMU_THUNK_PPI           *ThunkPpi;
  73   EFI_STATUS              Status;
  74   EMU_THUNK_PROTOCOL      *Thunk;
  75
  76   //
  77   // Locate EmuThunkPpi for retrieving standard output handle
  78   //
  79   Status = PeiServicesLocatePpi (
  80               &gEmuThunkPpiGuid,
  81               0,
  82               NULL,
  83               (VOID **) &ThunkPpi
  84              );
  85   if (!EFI_ERROR (Status)) {
  86     Thunk  = (EMU_THUNK_PROTOCOL *)ThunkPpi->Thunk ();
  87     return Thunk->WriteStdErr (Buffer, NumberOfBytes);
  88   }
  89
  90   return 0;
  91 }
  92
  93
  94 /**
  95   Read data from serial device and save the datas in buffer.
  96
  97   Reads NumberOfBytes data bytes from a serial device into the buffer
  98   specified by Buffer. The number of bytes actually read is returned.
  99   If the return value is less than NumberOfBytes, then the rest operation failed.
 100   If Buffer is NULL, then ASSERT().
 101   If NumberOfBytes is zero, then return 0.
 102
 103   @param  Buffer           The pointer to the data buffer to store the data read from the serial device.
 104   @param  NumberOfBytes    The number of bytes which will be read.
 105
 106   @retval 0                Read data failed; No data is to be read.
 107   @retval >0               The actual number of bytes read from serial device.
 108
 109 **/
 110 UINTN
 111 EFIAPI
 112 SerialPortRead (
 113   OUT UINT8     *Buffer,
 114   IN  UINTN     NumberOfBytes
 115   )
 116 {
 117   return 0;
 118 }
 119
 120 /**
 121   Polls a serial device to see if there is any data waiting to be read.
 122
 123   Polls a serial device to see if there is any data waiting to be read.
 124   If there is data waiting to be read from the serial device, then TRUE is returned.
 125   If there is no data waiting to be read from the serial device, then FALSE is returned.
 126
 127   @retval TRUE             Data is waiting to be read from the serial device.
 128   @retval FALSE            There is no data waiting to be read from the serial device.
 129
 130 **/
 131 BOOLEAN
 132 EFIAPI
 133 SerialPortPoll (
 134   VOID
 135   )
 136 {
 137   return FALSE;
 138 }
 139
 140