system76-edk2/ArmVirtPkg/Library/FdtPL011SerialPortLib/FdtPL011SerialPortLib.c

/** @file
  Serial I/O Port library functions with base address discovered from FDT

  Copyright (c) 2008 - 2010, Apple Inc. All rights reserved.<BR>
  Copyright (c) 2012 - 2013, ARM Ltd. All rights reserved.<BR>
  Copyright (c) 2014, Linaro Ltd. All rights reserved.<BR>
  Copyright (c) 2014, Red Hat, Inc.<BR>
  Copyright (c) 2015, Intel Corporation. All rights reserved.<BR>

  This program and the accompanying materials
  are licensed and made available under the terms and conditions of the BSD License
  which accompanies this distribution.  The full text of the license may be found at
  http://opensource.org/licenses/bsd-license.php

  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.

**/

#include <Base.h>

#include <Library/PcdLib.h>
#include <Library/SerialPortLib.h>
#include <Pi/PiBootMode.h>
#include <Uefi/UefiBaseType.h>
#include <Uefi/UefiMultiPhase.h>
#include <Pi/PiHob.h>
#include <Library/HobLib.h>
#include <Guid/EarlyPL011BaseAddress.h>

#include <Drivers/PL011Uart.h>

STATIC UINTN mSerialBaseAddress;

RETURN_STATUS
EFIAPI
SerialPortInitialize (
  VOID
  )
{
  return RETURN_SUCCESS;
}

/**

  Program hardware of Serial port

  @return    RETURN_NOT_FOUND if no PL011 base address could be found
             Otherwise, result of PL011UartInitializePort () is returned

**/
RETURN_STATUS
EFIAPI
FdtPL011SerialPortLibInitialize (
  VOID
  )
{
  VOID                *Hob;
  CONST UINT64        *UartBase;
  UINT64              BaudRate;
  UINT32              ReceiveFifoDepth;
  EFI_PARITY_TYPE     Parity;
  UINT8               DataBits;
  EFI_STOP_BITS_TYPE  StopBits;

  Hob = GetFirstGuidHob (&gEarlyPL011BaseAddressGuid);
  if (Hob == NULL || GET_GUID_HOB_DATA_SIZE (Hob) != sizeof *UartBase) {
    return RETURN_NOT_FOUND;
  }
  UartBase = GET_GUID_HOB_DATA (Hob);

  mSerialBaseAddress = (UINTN)*UartBase;
  if (mSerialBaseAddress == 0) {
    return RETURN_NOT_FOUND;
  }

  BaudRate = (UINTN)PcdGet64 (PcdUartDefaultBaudRate);
  ReceiveFifoDepth = 0; // Use the default value for Fifo depth
  Parity = (EFI_PARITY_TYPE)PcdGet8 (PcdUartDefaultParity);
  DataBits = PcdGet8 (PcdUartDefaultDataBits);
  StopBits = (EFI_STOP_BITS_TYPE) PcdGet8 (PcdUartDefaultStopBits);

  return PL011UartInitializePort (
           mSerialBaseAddress, &BaudRate, &ReceiveFifoDepth,
           &Parity, &DataBits, &StopBits);
}

/**
  Write data to serial device.

  @param  Buffer           Point of data buffer which need to be written.
  @param  NumberOfBytes    Number of output bytes which are cached in Buffer.

  @retval 0                Write data failed.
  @retval !0               Actual number of bytes written to serial device.

**/
UINTN
EFIAPI
SerialPortWrite (
  IN UINT8     *Buffer,
  IN UINTN     NumberOfBytes
  )
{
  if (mSerialBaseAddress != 0) {
    return PL011UartWrite (mSerialBaseAddress, Buffer, NumberOfBytes);
  }
  return 0;
}

/**
  Read data from serial device and save the data in buffer.

  @param  Buffer           Point of data buffer which need to be written.
  @param  NumberOfBytes    Number of output bytes which are cached in Buffer.

  @retval 0                Read data failed.
  @retval !0               Actual number of bytes read from serial device.

**/
UINTN
EFIAPI
SerialPortRead (
  OUT UINT8     *Buffer,
  IN  UINTN     NumberOfBytes
)
{
  if (mSerialBaseAddress != 0) {
    return PL011UartRead (mSerialBaseAddress, Buffer, NumberOfBytes);
  }
  return 0;
}

/**
  Check to see if any data is available to be read from the debug device.

  @retval TRUE       At least one byte of data is available to be read
  @retval FALSE      No data is available to be read

**/
BOOLEAN
EFIAPI
SerialPortPoll (
  VOID
  )
{
  if (mSerialBaseAddress != 0) {
    return PL011UartPoll (mSerialBaseAddress);
  }
  return FALSE;
}

/**
  Sets the baud rate, receive FIFO depth, transmit/receice time out, parity,
  data bits, and stop bits on a serial device.

  @param BaudRate           The requested baud rate. A BaudRate value of 0 will use the
                            device's default interface speed.
                            On output, the value actually set.
  @param ReveiveFifoDepth   The requested depth of the FIFO on the receive side of the
                            serial interface. A ReceiveFifoDepth value of 0 will use
                            the device's default FIFO depth.
                            On output, the value actually set.
  @param Timeout            The requested time out for a single character in microseconds.
                            This timeout applies to both the transmit and receive side of the
                            interface. A Timeout value of 0 will use the device's default time
                            out value.
                            On output, the value actually set.
  @param Parity             The type of parity to use on this serial device. A Parity value of
                            DefaultParity will use the device's default parity value.
                            On output, the value actually set.
  @param DataBits           The number of data bits to use on the serial device. A DataBits
                            vaule of 0 will use the device's default data bit setting.
                            On output, the value actually set.
  @param StopBits           The number of stop bits to use on this serial device. A StopBits
                            value of DefaultStopBits will use the device's default number of
                            stop bits.
                            On output, the value actually set.

  @retval RETURN_SUCCESS            The new attributes were set on the serial device.
  @retval RETURN_UNSUPPORTED        The serial device does not support this operation.
  @retval RETURN_INVALID_PARAMETER  One or more of the attributes has an unsupported value.
  @retval RETURN_DEVICE_ERROR       The serial device is not functioning correctly.

**/
RETURN_STATUS
EFIAPI
SerialPortSetAttributes (
  IN OUT UINT64             *BaudRate,
  IN OUT UINT32             *ReceiveFifoDepth,
  IN OUT UINT32             *Timeout,
  IN OUT EFI_PARITY_TYPE    *Parity,
  IN OUT UINT8              *DataBits,
  IN OUT EFI_STOP_BITS_TYPE *StopBits
  )
{
  return RETURN_UNSUPPORTED;
}

/**
  Sets the control bits on a serial device.

  @param Control                Sets the bits of Control that are settable.

  @retval RETURN_SUCCESS        The new control bits were set on the serial device.
  @retval RETURN_UNSUPPORTED    The serial device does not support this operation.
  @retval RETURN_DEVICE_ERROR   The serial device is not functioning correctly.

**/
RETURN_STATUS
EFIAPI
SerialPortSetControl (
  IN UINT32 Control
  )
{
  return RETURN_UNSUPPORTED;
}

/**
  Retrieve the status of the control bits on a serial device.

  @param Control                A pointer to return the current control signals from the serial device.

  @retval RETURN_SUCCESS        The control bits were read from the serial device.
  @retval RETURN_UNSUPPORTED    The serial device does not support this operation.
  @retval RETURN_DEVICE_ERROR   The serial device is not functioning correctly.

**/
RETURN_STATUS
EFIAPI
SerialPortGetControl (
  OUT UINT32 *Control
  )
{
  return RETURN_UNSUPPORTED;
}