ArmPkg: Add OemMiscLibNull library to ArmPkg.dsc

[mirror_edk2.git] / ArmPkg / Library / SemiHostingSerialPortLib / SerialPortLib.c

/** @file\r
  Serial I/O Port library functions with no library constructor/destructor\r
\r
  Copyright (c) 2008 - 2009, Apple Inc. All rights reserved.<BR>\r
  Copyright (c) 2021, Arm Limited. All rights reserved.<BR>\r
\r
  SPDX-License-Identifier: BSD-2-Clause-Patent\r
\r
**/\r
\r
#include <Uefi.h>\r
#include <Library/DebugLib.h>\r
#include <Library/SemihostLib.h>\r
#include <Library/SerialPortLib.h>\r
\r
\r
/*\r
\r
  Programmed hardware of Serial port.\r
\r
  @return    Always return EFI_UNSUPPORTED.\r
\r
**/\r
RETURN_STATUS\r
EFIAPI\r
SerialPortInitialize (\r
  VOID\r
  )\r
{\r
  if (SemihostConnectionSupported ()) {\r
    return RETURN_SUCCESS;\r
  } else {\r
    return RETURN_UNSUPPORTED;\r
  }\r
}\r
\r
/**\r
  Write data to serial device.\r
\r
  @param  Buffer           Point of data buffer which need to be writed.\r
  @param  NumberOfBytes    Number of output bytes which are cached in Buffer.\r
\r
  @retval 0                Write data failed.\r
  @retval !0               Actual number of bytes writed to serial device.\r
\r
**/\r
\r
#define PRINT_BUFFER_SIZE       512\r
#define PRINT_BUFFER_THRESHOLD  (PRINT_BUFFER_SIZE - 4)\r
\r
UINTN\r
EFIAPI\r
SerialPortWrite (\r
  IN UINT8     *Buffer,\r
  IN UINTN     NumberOfBytes\r
)\r
{\r
  UINT8 PrintBuffer[PRINT_BUFFER_SIZE];\r
  UINTN SourceIndex;\r
  UINTN DestinationIndex;\r
  UINT8 CurrentCharacter;\r
\r
  SourceIndex      = 0;\r
  DestinationIndex = 0;\r
\r
  while (SourceIndex < NumberOfBytes)\r
  {\r
      CurrentCharacter = Buffer[SourceIndex++];\r
\r
      switch (CurrentCharacter)\r
      {\r
      case '\r':\r
          continue;\r
\r
      case '\n':\r
          PrintBuffer[DestinationIndex++] = ' ';\r
          // fall through\r
\r
      default:\r
          PrintBuffer[DestinationIndex++] = CurrentCharacter;\r
          break;\r
      }\r
\r
      if (DestinationIndex > PRINT_BUFFER_THRESHOLD)\r
      {\r
          PrintBuffer[DestinationIndex] = '\0';\r
          SemihostWriteString ((CHAR8 *) PrintBuffer);\r
\r
          DestinationIndex = 0;\r
      }\r
  }\r
\r
  if (DestinationIndex > 0)\r
  {\r
      PrintBuffer[DestinationIndex] = '\0';\r
      SemihostWriteString ((CHAR8 *) PrintBuffer);\r
  }\r
\r
  return NumberOfBytes;\r
}\r
\r
\r
/**\r
  Read data from serial device and save the datas in buffer.\r
\r
  @param  Buffer           Point of data buffer which need to be writed.\r
  @param  NumberOfBytes    Number of output bytes which are cached in Buffer.\r
\r
  @retval 0                Read data failed.\r
  @retval !0               Actual number of bytes read from serial device.\r
\r
**/\r
UINTN\r
EFIAPI\r
SerialPortRead (\r
  OUT UINT8     *Buffer,\r
  IN  UINTN     NumberOfBytes\r
)\r
{\r
  *Buffer = SemihostReadCharacter ();\r
  return 1;\r
}\r
\r
\r
\r
/**\r
  Check to see if any data is available to be read from the debug device.\r
\r
  @retval TRUE       At least one byte of data is available to be read\r
  @retval FALSE      No data is available to be read\r
\r
**/\r
BOOLEAN\r
EFIAPI\r
SerialPortPoll (\r
  VOID\r
  )\r
{\r
  // Since SemiHosting read character is blocking always say we have a char ready?\r
  return SemihostConnectionSupported ();\r
}\r
\r