ArmPlatformPkg/Library/PL011SerialPortLib/PL011SerialPortLib.c

   1 /** @file
   2   Serial I/O Port library functions with no library constructor/destructor
   3
   4
   5   Copyright (c) 2008 - 2010, Apple Inc. All rights reserved.<BR>
   6
   7   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 <Include/Uefi.h>
  18 #include <Library/SerialPortLib.h>
  19 #include <Library/IoLib.h>
  20 #include <Drivers/PL011Uart.h>
  21 #include <ArmPlatform.h>
  22
  23 /*
  24
  25   Programmed hardware of Serial port.
  26
  27   @return    Always return EFI_UNSUPPORTED.
  28
  29 **/
  30 RETURN_STATUS
  31 EFIAPI
  32 SerialPortInitialize (
  33   VOID
  34   )
  35 {
  36         if (PL011_CONSOLE_UART_SPEED == 115200) {
  37                 // Initialize baud rate generator
  38                 MmioWrite32 (PL011_CONSOLE_UART_BASE + UARTIBRD, UART_115200_IDIV);
  39                 MmioWrite32 (PL011_CONSOLE_UART_BASE + UARTFBRD, UART_115200_FDIV);
  40         } else if (PL011_CONSOLE_UART_SPEED == 38400) {
  41                 // Initialize baud rate generator
  42                 MmioWrite32 (PL011_CONSOLE_UART_BASE + UARTIBRD, UART_38400_IDIV);
  43                 MmioWrite32 (PL011_CONSOLE_UART_BASE + UARTFBRD, UART_38400_FDIV);
  44         } else if (PL011_CONSOLE_UART_SPEED == 19200) {
  45                 // Initialize baud rate generator
  46                 MmioWrite32 (PL011_CONSOLE_UART_BASE + UARTIBRD, UART_19200_IDIV);
  47                 MmioWrite32 (PL011_CONSOLE_UART_BASE + UARTFBRD, UART_19200_FDIV);
  48         } else {
  49                 return EFI_INVALID_PARAMETER;
  50         }
  51
  52   // No parity, 1 stop, no fifo, 8 data bits
  53   MmioWrite32 (PL011_CONSOLE_UART_BASE + UARTLCR_H, 0x60);
  54
  55   // Clear any pending errors
  56   MmioWrite32 (PL011_CONSOLE_UART_BASE + UARTECR, 0);
  57
  58   // enable tx, rx, and uart overall
  59   MmioWrite32 (PL011_CONSOLE_UART_BASE + UARTCR, 0x301);
  60
  61   return EFI_SUCCESS;
  62 }
  63
  64 /**
  65   Write data to serial device.
  66
  67   @param  Buffer           Point of data buffer which need to be writed.
  68   @param  NumberOfBytes    Number of output bytes which are cached in Buffer.
  69
  70   @retval 0                Write data failed.
  71   @retval !0               Actual number of bytes writed to serial device.
  72
  73 **/
  74 UINTN
  75 EFIAPI
  76 SerialPortWrite (
  77   IN UINT8     *Buffer,
  78   IN UINTN     NumberOfBytes
  79 )
  80 {
  81         UINTN  Count;
  82
  83         for (Count = 0; Count < NumberOfBytes; Count++, Buffer++) {
  84                 while ((MmioRead32 (PL011_CONSOLE_UART_BASE + UARTFR) & UART_TX_EMPTY_FLAG_MASK) == 0);
  85                 MmioWrite8 (PL011_CONSOLE_UART_BASE + UARTDR, *Buffer);
  86         }
  87
  88         return NumberOfBytes;
  89 }
  90
  91 /**
  92   Read data from serial device and save the datas in buffer.
  93
  94   @param  Buffer           Point of data buffer which need to be writed.
  95   @param  NumberOfBytes    Number of output bytes which are cached in Buffer.
  96
  97   @retval 0                Read data failed.
  98   @retval !0               Aactual number of bytes read from serial device.
  99
 100 **/
 101 UINTN
 102 EFIAPI
 103 SerialPortRead (
 104   OUT UINT8     *Buffer,
 105   IN  UINTN     NumberOfBytes
 106 )
 107 {
 108   UINTN   Count;
 109
 110         for (Count = 0; Count < NumberOfBytes; Count++, Buffer++) {
 111                 while ((MmioRead32 (PL011_CONSOLE_UART_BASE + UARTFR) & UART_RX_EMPTY_FLAG_MASK) != 0);
 112                 *Buffer = MmioRead8 (PL011_CONSOLE_UART_BASE + UARTDR);
 113         }
 114
 115         return NumberOfBytes;
 116 }
 117
 118 /**
 119   Check to see if any data is avaiable to be read from the debug device.
 120
 121   @retval EFI_SUCCESS       At least one byte of data is avaiable to be read
 122   @retval EFI_NOT_READY     No data is avaiable to be read
 123   @retval EFI_DEVICE_ERROR  The serial device is not functioning properly
 124
 125 **/
 126 BOOLEAN
 127 EFIAPI
 128 SerialPortPoll (
 129   VOID
 130   )
 131 {
 132   return ((MmioRead32 (PL011_CONSOLE_UART_BASE + UARTFR) & UART_RX_EMPTY_FLAG_MASK) == 0);
 133 }