Re: [edk2-devel] [platform/devel-riscv-v2 PATCHv5 09/18] U5SeriesPkg/SerialIoLib: Platform Serial Port library

["Mark Salter" <msalter@redhat.com>]

On Mon, 2019-10-28 at 12:20 +0800, Abner Chang wrote:
> Serial Port library for U5 series platform.
> 
> Signed-off-by: Abner Chang <abner.chang@hpe.com>
> 
> Cc: Michael D Kinney <michael.d.kinney@intel.com>
> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
> Cc: Leif Lindholm <leif.lindholm@linaro.org>
> Cc: Gilbert Chen <gilbert.chen@hpe.com>
> Cc: Palmer Dabbelt <palmer@sifive.com>
> Signed-off-by: Abner Chang <abner.chang@hpe.com>
> ---
>  .../Library/SerialIoLib/SerialIoLib.inf            |  38 ++++
>  .../Library/SerialIoLib/SerialPortLib.c            | 253 +++++++++++++++++++++
>  .../Library/SerialIoLib/U5SerialPortLib.uni        |  16 ++
>  3 files changed, 307 insertions(+)
>  create mode 100644 Platform/SiFive/U5SeriesPkg/Library/SerialIoLib/SerialIoLib.inf
>  create mode 100644 Platform/SiFive/U5SeriesPkg/Library/SerialIoLib/SerialPortLib.c
>  create mode 100644 Platform/SiFive/U5SeriesPkg/Library/SerialIoLib/U5SerialPortLib.uni
> 
> diff --git a/Platform/SiFive/U5SeriesPkg/Library/SerialIoLib/SerialIoLib.inf b/Platform/SiFive/U5SeriesPkg/Library/SerialIoLib/SerialIoLib.inf
> new file mode 100644
> index 0000000..0044f84
> --- /dev/null
> +++ b/Platform/SiFive/U5SeriesPkg/Library/SerialIoLib/SerialIoLib.inf
> @@ -0,0 +1,38 @@
> +## @file
> +#   Library instance for SerialIo library class
> +#
> +#  Copyright (c) 2019, Hewlett Packard Enterprise Development LP. All rights reserved.<BR>
> +#
> +#  SPDX-License-Identifier: BSD-2-Clause-Patent
> +#
> +##
> +
> +[Defines]
> +  INF_VERSION                    = 0x0001001b
> +  BASE_NAME                      = U5SerialPortLib
> +  MODULE_UNI_FILE                = U5SerialPortLib.uni
> +  FILE_GUID                      = FCC4FD2B-2FF6-4FFA-B363-7C1111E5DCE9
> +  MODULE_TYPE                    = BASE
> +  VERSION_STRING                 = 1.0
> +  LIBRARY_CLASS                  = SerialPortLib
> +#
> +# The following information is for reference only and not required by the build tools.
> +#
> +#  VALID_ARCHITECTURES           = RISCV64
> +#
> +[Packages]
> +  MdePkg/MdePkg.dec
> +  RiscVPlatformPkg/RiscVPlatformPkg.dec
> +  RiscVPkg/RiscVPkg.dec
> +  Platform/SiFive/U5SeriesPkg/U5SeriesPkg.dec
> +
> +[LibraryClasses]
> +  BaseLib
> +  IoLib
> +  RiscVOpensbiLib
> +
> +[FixedPcd]
> +  gSiFiveU5SeriesPlatformsPkgTokenSpaceGuid.PcdU5UartBase
> +
> +[Sources]
> +  SerialPortLib.c
> diff --git a/Platform/SiFive/U5SeriesPkg/Library/SerialIoLib/SerialPortLib.c b/Platform/SiFive/U5SeriesPkg/Library/SerialIoLib/SerialPortLib.c
> new file mode 100644
> index 0000000..5e06515
> --- /dev/null
> +++ b/Platform/SiFive/U5SeriesPkg/Library/SerialIoLib/SerialPortLib.c
> @@ -0,0 +1,253 @@
> +/** @file
> +  UART Serial Port library functions
> +
> +  Copyright (c) 2019, Hewlett Packard Enterprise Development LP. All rights reserved.<BR>
> +
> +  SPDX-License-Identifier: BSD-2-Clause-Patent
> +
> +**/
> +
> +#include <Base.h>
> +#include <Library/IoLib.h>
> +#include <Library/SerialPortLib.h>
> +#include <include/sbi_utils/serial/sifive-uart.h> // Reference to header file in opensbi
> +
> +//---------------------------------------------
> +// UART Register Offsets
> +//---------------------------------------------
> +
> +#define UART_REG_IP     5
> +#define UART_IP_RXWM    0x02
> +
> +//---------------------------------------------
> +// UART Settings
> +//---------------------------------------------
> +
> +#define UART_BAUDRATE  115200
> +#define SYS_CLK        100000000
                          ^^^^^^^^^^
   This should be         1000000000
   1GHz, not 100MHz

> +
> +BOOLEAN Initiated = FALSE;
> +
> +/**
> +  Initialize the serial device hardware.
> +
> +  If no initialization is required, then return RETURN_SUCCESS.
> +  If the serial device was successfuly initialized, then return RETURN_SUCCESS.
> +  If the serial device could not be initialized, then return RETURN_DEVICE_ERROR.
> +
> +  @retval RETURN_SUCCESS        The serial device was initialized.
> +  @retval RETURN_DEVICE_ERROR   The serail device could not be initialized.
> +
> +**/
> +RETURN_STATUS
> +EFIAPI
> +SerialPortInitialize (
> +  VOID
> +  )
> +{
> +  if (Initiated) {
> +    return RETURN_SUCCESS;
> +  }
> +  if (sifive_uart_init(FixedPcdGet32(PcdU5UartBase), SYS_CLK / 2, UART_BAUDRATE) != 0) {
> +      return EFI_DEVICE_ERROR;
> +  }
> +  Initiated = TRUE;
> +  return RETURN_SUCCESS;
> +}
> +
> +/**
> +  Write data from buffer to serial device.
> +
> +  Writes NumberOfBytes data bytes from Buffer to the serial device.
> +  The number of bytes actually written to the serial device is returned.
> +  If the return value is less than NumberOfBytes, then the write operation failed.
> +
> +  If Buffer is NULL, then ASSERT().
> +
> +  If NumberOfBytes is zero, then return 0.
> +
> +  @param  Buffer           Pointer to the data buffer to be written.
> +  @param  NumberOfBytes    Number of bytes to written to the serial device.
> +
> +  @retval 0                NumberOfBytes is 0.
> +  @retval >0               The number of bytes written to the serial device.
> +                           If this value is less than NumberOfBytes, then the write operation failed.
> +
> +**/
> +UINTN
> +EFIAPI
> +SerialPortWrite (
> +  IN UINT8     *Buffer,
> +  IN UINTN     NumberOfBytes
> +  )
> +{
> +  UINTN Index;
> +
> +  if (Buffer == NULL || Initiated == FALSE) {
> +    return 0;
> +  }
> +
> +  for(Index = 0; Index < NumberOfBytes; Index ++) {
> +    sifive_uart_putc (Buffer [Index]);
> +  }
> +
> +  return Index;
> +}
> +
> +/**
> +  Reads data from a serial device into a buffer.
> +
> +  @param  Buffer           Pointer to the data buffer to store the data read from the serial device.
> +  @param  NumberOfBytes    Number of bytes to read from the serial device.
> +
> +  @retval 0                NumberOfBytes is 0.
> +  @retval >0               The number of bytes read from the serial device.
> +                           If this value is less than NumberOfBytes, then the read operation failed.
> +
> +**/
> +UINTN
> +EFIAPI
> +SerialPortRead (
> +  OUT UINT8     *Buffer,
> +  IN  UINTN     NumberOfBytes
> +  )
> +{
> +  UINTN Index;
> +
> +  if (NULL == Buffer || Initiated == FALSE) {
> +    return 0;
> +  }
> +
> +  for(Index = 0; Index < NumberOfBytes; Index ++) {
> +    Buffer [Index] = (UINT8)sifive_uart_getc ();
> +  }
> +
> +  return Index;
> +}
> +
> +/**
> +  Polls a serial device to see if there is any data waiting to be read.
> +
> +  Polls aserial device to see if there is any data waiting to be read.
> +  If there is data waiting to be read from the serial device, then TRUE is returned.
> +  If there is no data waiting to be read from the serial device, then FALSE is returned.
> +
> +  @retval TRUE             Data is waiting to be read from the serial device.
> +  @retval FALSE            There is no data waiting to be read from the serial device.
> +
> +**/
> +BOOLEAN
> +EFIAPI
> +SerialPortPoll (
> +  VOID
> +  )
> +{
> +  STATIC volatile UINT32 * const uart = (UINT32 *)FixedPcdGet32(PcdU5UartBase);
> +  UINT32 IP;
> +
> +  if (Initiated == FALSE) {
> +    return FALSE;
> +  }
> +  IP = MmioRead32 ((UINTN)(uart + UART_REG_IP));
> +  if(IP & UART_IP_RXWM) {
> +    return TRUE;
> +  }
> +  else {
> +    return FALSE;
> +  }
> +}
> +
> +/**
> +  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
> +  )
> +{
> +  if (Initiated == FALSE) {
> +    return EFI_NOT_READY;
> +  }
> +  return RETURN_SUCCESS;
> +}
> +
> +/**
> +  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
> +  )
> +{
> +  if (Initiated == FALSE) {
> +    return EFI_NOT_READY;
> +  }
> +  *Control = 0;
> +  return RETURN_SUCCESS;
> +}
> +
> +/**
> +  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
> +  )
> +{
> +  if (Initiated == FALSE) {
> +    return EFI_NOT_READY;
> +  }
> +  return RETURN_SUCCESS;
> +}
> diff --git a/Platform/SiFive/U5SeriesPkg/Library/SerialIoLib/U5SerialPortLib.uni b/Platform/SiFive/U5SeriesPkg/Library/SerialIoLib/U5SerialPortLib.uni
> new file mode 100644
> index 0000000..49163bd
> --- /dev/null
> +++ b/Platform/SiFive/U5SeriesPkg/Library/SerialIoLib/U5SerialPortLib.uni
> @@ -0,0 +1,16 @@
> +// /** @file
> +// Library instance for SerialIo library class
> +//
> +// Library instance for SerialIO library class.
> +//
> +// Copyright (c) 2006 - 2014, Intel Corporation. All rights reserved.<BR>
> +//
> +// SPDX-License-Identifier: BSD-2-Clause-Patent
> +//
> +// **/
> +
> +
> +#string STR_MODULE_ABSTRACT             #language en-US "Library instance for SerialIO library class"
> +
> +#string STR_MODULE_DESCRIPTION          #language en-US "Library instance for SerialIO library class."
> +