Omap35xxPkg/Library/SerialPortLib/SerialPortLib.c

   1 /** @file
   2   Serial I/O Port library functions with no library constructor/destructor
   3
   4
   5   Copyright (c) 2008-2009, Apple Inc. All rights reserved.
   6
   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 **/
  16
  17 #include <Base.h>
  18 #include <Library/DebugLib.h>
  19 #include <Library/SerialPortLib.h>
  20 #include <Library/PcdLib.h>
  21 #include <Library/IoLib.h>
  22 #include <Library/OmapLib.h>
  23 #include <Omap3530/Omap3530.h>
  24
  25 /*
  26
  27   Programmed hardware of Serial port.
  28
  29   @return    Always return EFI_UNSUPPORTED.
  30
  31 **/
  32 RETURN_STATUS
  33 EFIAPI
  34 SerialPortInitialize (
  35   VOID
  36   )
  37 {
  38   // assume assembly code at reset vector has setup UART
  39   return RETURN_SUCCESS;
  40 }
  41
  42 /**
  43   Write data to serial device.
  44
  45   @param  Buffer           Point of data buffer which need to be writed.
  46   @param  NumberOfBytes    Number of output bytes which are cached in Buffer.
  47
  48   @retval 0                Write data failed.
  49   @retval !0               Actual number of bytes writed to serial device.
  50
  51 **/
  52 UINTN
  53 EFIAPI
  54 SerialPortWrite (
  55   IN UINT8     *Buffer,
  56   IN UINTN     NumberOfBytes
  57 )
  58 {
  59   UINT32  LSR = UartBase(PcdGet32(PcdOmap35xxConsoleUart)) + UART_LSR_REG;
  60   UINT32  THR = UartBase(PcdGet32(PcdOmap35xxConsoleUart)) + UART_THR_REG;
  61   UINTN   Count;
  62
  63   for (Count = 0; Count < NumberOfBytes; Count++, Buffer++) {
  64     while ((MmioRead8(LSR) & UART_LSR_TX_FIFO_E_MASK) == UART_LSR_TX_FIFO_E_NOT_EMPTY);
  65     MmioWrite8(THR, *Buffer);
  66   }
  67
  68   return NumberOfBytes;
  69 }
  70
  71
  72 /**
  73   Read data from serial device and save the datas in buffer.
  74
  75   @param  Buffer           Point of data buffer which need to be writed.
  76   @param  NumberOfBytes    Number of output bytes which are cached in Buffer.
  77
  78   @retval 0                Read data failed.
  79   @retval !0               Aactual number of bytes read from serial device.
  80
  81 **/
  82 UINTN
  83 EFIAPI
  84 SerialPortRead (
  85   OUT UINT8     *Buffer,
  86   IN  UINTN     NumberOfBytes
  87 )
  88 {
  89   UINT32  LSR = UartBase(PcdGet32(PcdOmap35xxConsoleUart)) + UART_LSR_REG;
  90   UINT32  RBR = UartBase(PcdGet32(PcdOmap35xxConsoleUart)) + UART_RBR_REG;
  91   UINTN   Count;
  92
  93   for (Count = 0; Count < NumberOfBytes; Count++, Buffer++) {
  94     while ((MmioRead8(LSR) & UART_LSR_RX_FIFO_E_MASK) == UART_LSR_RX_FIFO_E_EMPTY);
  95     *Buffer = MmioRead8(RBR);
  96   }
  97
  98   return NumberOfBytes;
  99 }
 100
 101
 102 /**
 103   Check to see if any data is avaiable to be read from the debug device.
 104
 105   @retval EFI_SUCCESS       At least one byte of data is avaiable to be read
 106   @retval EFI_NOT_READY     No data is avaiable to be read
 107   @retval EFI_DEVICE_ERROR  The serial device is not functioning properly
 108
 109 **/
 110 BOOLEAN
 111 EFIAPI
 112 SerialPortPoll (
 113   VOID
 114   )
 115 {
 116   UINT32 LSR = UartBase(PcdGet32(PcdOmap35xxConsoleUart)) + UART_LSR_REG;
 117
 118   if ((MmioRead8(LSR) & UART_LSR_RX_FIFO_E_MASK) == UART_LSR_RX_FIFO_E_NOT_EMPTY) {
 119     return TRUE;
 120   } else {
 121     return FALSE;
 122   }
 123 }
 124