sam5250.c File Reference

#include "common.h"

Macros
#define	ULCON   0x00
#define	UCON   0x04
#define	UFCON   0x08
#define	UTRSTAT   0x10
#define	UERSTAT   0x14
#define	UFSTAT   0x18
#define	UTXH   0x20
#define	URXH   0x24
#define	UINTP   0x30
#define	UINTM   0x38
#define	UFSTAT_TXFE   (1 << 24)
#define	UTRSTAT_RXFE   (1 << 0)
#define	UERSTAT_OE   (1 << 0)
#define	UERSTAT_PE   (1 << 1)
#define	UERSTAT_FE   (1 << 2)
#define	UERSTAT_BE   (1 << 3)

Functions
BOOLEAN	Sam5250SetBaud (_Inout_ PCPPORT Port, ULONG Rate)
BOOLEAN	Sam5250InitializePort (_In_opt_ _Null_terminated_ PCHAR LoadOptions, _Inout_ PCPPORT Port, BOOLEAN MemoryMapped, UCHAR AccessSize, UCHAR BitWidth)
UART_STATUS	Sam5250GetByte (_Inout_ PCPPORT Port, _Out_ PUCHAR Byte)
UART_STATUS	Sam5250PutByte (_Inout_ PCPPORT Port, UCHAR Byte, BOOLEAN BusyWait)
BOOLEAN	Sam5250RxReady (_Inout_ PCPPORT Port)

Variables
UART_HARDWARE_DRIVER	Sam5250HardwareDriver

Macro Definition Documentation

UCON

#define UCON   0x04

UERSTAT

#define UERSTAT   0x14

UERSTAT_BE

#define UERSTAT_BE   (1 << 3)

UERSTAT_FE

#define UERSTAT_FE   (1 << 2)

UERSTAT_OE

#define UERSTAT_OE   (1 << 0)

UERSTAT_PE

#define UERSTAT_PE   (1 << 1)

UFCON

#define UFCON   0x08

UFSTAT

#define UFSTAT   0x18

UFSTAT_TXFE

#define UFSTAT_TXFE   (1 << 24)

UINTM

#define UINTM   0x38

UINTP

#define UINTP   0x30

ULCON

#define ULCON   0x00

URXH

#define URXH   0x24

UTRSTAT

#define UTRSTAT   0x10

UTRSTAT_RXFE

#define UTRSTAT_RXFE   (1 << 0)

UTXH

#define UTXH   0x20

Function Documentation

Sam5250GetByte()

UART_STATUS Sam5250GetByte	(	_Inout_ PCPPORT	Port,
		_Out_ PUCHAR	Byte )

{
    ULONG Fsr;
    ULONG Error;
    ULONG Value;
 
    if ((Port == NULL) || (Port->Address == NULL))
    {
        return UartNotReady;
    }
 
    //
    // Get FIFO status.
    //
 
    Fsr = READ_REGISTER_ULONG((PULONG)(Port->Address + UTRSTAT));
 
    //
    // Is at least one character available?
    //
 
    if ((Fsr & UTRSTAT_RXFE) != 0)
    {
        //
        // Fetch the data byte and associated error information.
        //
 
        Value = READ_REGISTER_ULONG((PULONG)(Port->Address + URXH));
 
        //
        // Check for errors.  Deliberately don't treat overrun as an error.
        //
 
        Error = READ_REGISTER_ULONG((PULONG)(Port->Address + UERSTAT));
        if ((Error & (UERSTAT_PE | UERSTAT_FE | UERSTAT_BE)) != 0)
        {
            *Byte = 0;
            return UartError;
        }
 
        *Byte = Value & (UCHAR)0xFF;
        return UartSuccess;
    }
 
    return UartNoData;
}

Sam5250InitializePort()

BOOLEAN Sam5250InitializePort	(	_In_opt_ _Null_terminated_ PCHAR	LoadOptions,
		_Inout_ PCPPORT	Port,
		BOOLEAN	MemoryMapped,
		UCHAR	AccessSize,
		UCHAR	BitWidth )

{
    UNREFERENCED_PARAMETER(LoadOptions);
    UNREFERENCED_PARAMETER(AccessSize);
    UNREFERENCED_PARAMETER(BitWidth);
 
    if (MemoryMapped == FALSE)
    {
        return FALSE;
    }
 
    Port->Flags = 0;
 
    //
    // Disable UART.
    //
 
    WRITE_REGISTER_ULONG((PULONG)(Port->Address + UCON), 0);
 
    //
    // Set word length to 8 bits and disable parity.
    //
 
    WRITE_REGISTER_ULONG((PULONG)(Port->Address + ULCON), 0x3);
 
    //
    // Enable the FIFO.
    //
 
    WRITE_REGISTER_ULONG((PULONG)(Port->Address + UFCON), 0x1);
 
    //
    // Mask all interrupts.
    //
 
    WRITE_REGISTER_ULONG((PULONG)(Port->Address + UINTM), 0xF);
 
    //
    // Clear all interrupts.
    //
 
    WRITE_REGISTER_ULONG((PULONG)(Port->Address + UINTP), 0xF);
 
    //
    // Enable UART, enable Transmit (mode: 01) and Receive (mode: 01).
    //
 
    WRITE_REGISTER_ULONG((PULONG)(Port->Address + UCON), 0x5);
    return TRUE;
}

Sam5250PutByte()

UART_STATUS Sam5250PutByte	(	_Inout_ PCPPORT	Port,
		UCHAR	Byte,
		BOOLEAN	BusyWait )

{
    if ((Port == NULL) || (Port->Address == NULL))
    {
        return UartNotReady;
    }
 
    //
    //  Wait for port to be free and FIFO not full.
    //
    // _ARM_WORKAROUND_ Modem control is not supported.
    //
 
    if (BusyWait != FALSE)
    {
        while (READ_REGISTER_ULONG((PULONG)(Port->Address + UFSTAT)) & (UFSTAT_TXFE))
            ;
    }
    else
    {
        if (READ_REGISTER_ULONG((PULONG)(Port->Address + UFSTAT)) & (UFSTAT_TXFE))
        {
            return UartNotReady;
        }
    }
 
    //
    // Send the byte.
    //
 
    WRITE_REGISTER_ULONG((PULONG)(Port->Address + UTXH), (ULONG)Byte);
    return UartSuccess;
}

Sam5250RxReady()

BOOLEAN Sam5250RxReady

(

_Inout_ PCPPORT

Port

)

{
    ULONG Flags;
 
    if ((Port == NULL) || (Port->Address == NULL))
    {
        return FALSE;
    }
 
    //
    // Read the Flag Register to determine if there is any pending data to read.
    //
 
    Flags = READ_REGISTER_ULONG((PULONG)(Port->Address + UTRSTAT));
    if ((Flags & UTRSTAT_RXFE) != 0)
    {
        return TRUE;
    }
 
    return FALSE;
}

Sam5250SetBaud()

BOOLEAN Sam5250SetBaud	(	_Inout_ PCPPORT	Port,
		ULONG	Rate )

{
    if ((Port == NULL) || (Port->Address == NULL))
    {
        return FALSE;
    }
 
    //
    // There is no way to determine reference clock frequency for this UART so
    // just remember the desired baud rate but don't do anything else.
    //
 
    Port->BaudRate = Rate;
    return TRUE;
}

Variable Documentation

Sam5250HardwareDriver

UART_HARDWARE_DRIVER Sam5250HardwareDriver

Initial value:

= {
    Sam5250InitializePort,
    Sam5250SetBaud,
    Sam5250GetByte,
    Sam5250PutByte,
    Sam5250RxReady}

                                             {
    Sam5250InitializePort,
    Sam5250SetBaud,
    Sam5250GetByte,
    Sam5250PutByte,
    Sam5250RxReady};