mx6uart.c File Reference

#include "common.h"
#include <pshpack1.h>
#include <poppack.h>

Classes
struct	_MX6_UART_REGISTERS

Macros
#define	MX6_UCR1_UARTEN   (1 << 0)
#define	MX6_UCR2_TXEN   (1 << 2)
#define	MX6_UCR2_RXEN   (1 << 1)
#define	MX6_UCR2_PREN   (1 << 8)
#define	MX6_UCR2_STPB   (1 << 6)
#define	MX6_UCR2_WRDSZ   (1 << 5)
#define	MX6_USR1_TRDY   (1 << 13)
#define	MX6_USR2_RDR   (1 << 0)
#define	MX6_RXD_CHARRDY   (1 << 15)
#define	MX6_RXD_ERR   (1 << 14)
#define	MX6_RXD_FRMERR   (1 << 12)
#define	MX6_RXD_PARERR   (1 << 10)
#define	MX6_RXD_DATA_MASK   0xFF
#define	MX6_UFCR_TXTL_SHIFT   10
#define	MX6_UFCR_TXTL_MAX   32
#define	MX6_UFCR_TXTL_MASK   0x3F
#define	MX6_USR1_PRTERRY_MASK   (1 << 15)
#define	MX6_USR1_ESCF_MASK   (1 << 11)
#define	MX6_USR1_FRMER_MASK   (1 << 10)
#define	MX6_USR1_AGTIM_MASK   (1 << 8)
#define	MX6_USR1_DTRD_MASK   (1 << 7)
#define	MX6_USR1_AIRINT_MASK   (1 << 5)
#define	MX6_USR1_AWAKE_MASK   (1 << 4)
#define	MX6_USR2_RDRDY_MASK   1
#define	MX6_UTS_RXEMPTY_MASK   (1 << 5)

Typedefs
typedef struct _MX6_UART_REGISTERS	MX6_UART_REGISTERS
typedef struct _MX6_UART_REGISTERS *	PMX6_UART_REGISTERS

Functions
	C_ASSERT (FIELD_OFFSET(MX6_UART_REGISTERS, Umcr)==0xB8)
BOOLEAN	MX6InitializePort (_In_opt_ _Null_terminated_ PCHAR LoadOptions, _Inout_ PCPPORT Port, BOOLEAN MemoryMapped, UCHAR AccessSize, UCHAR BitWidth)
BOOLEAN	MX6SetBaud (_Inout_ PCPPORT Port, ULONG Rate)
UART_STATUS	MX6GetByte (_Inout_ PCPPORT Port, _Out_ PUCHAR Byte)
UART_STATUS	MX6PutByte (_Inout_ PCPPORT Port, UCHAR Byte, BOOLEAN BusyWait)
BOOLEAN	MX6RxReady (_Inout_ PCPPORT Port)

Variables
UART_HARDWARE_DRIVER	MX6HardwareDriver

Macro Definition Documentation

MX6_RXD_CHARRDY

#define MX6_RXD_CHARRDY   (1 << 15)

MX6_RXD_DATA_MASK

#define MX6_RXD_DATA_MASK   0xFF

MX6_RXD_ERR

#define MX6_RXD_ERR   (1 << 14)

MX6_RXD_FRMERR

#define MX6_RXD_FRMERR   (1 << 12)

MX6_RXD_PARERR

#define MX6_RXD_PARERR   (1 << 10)

MX6_UCR1_UARTEN

#define MX6_UCR1_UARTEN   (1 << 0)

MX6_UCR2_PREN

#define MX6_UCR2_PREN   (1 << 8)

MX6_UCR2_RXEN

#define MX6_UCR2_RXEN   (1 << 1)

MX6_UCR2_STPB

#define MX6_UCR2_STPB   (1 << 6)

MX6_UCR2_TXEN

#define MX6_UCR2_TXEN   (1 << 2)

MX6_UCR2_WRDSZ

#define MX6_UCR2_WRDSZ   (1 << 5)

MX6_UFCR_TXTL_MASK

#define MX6_UFCR_TXTL_MASK   0x3F

MX6_UFCR_TXTL_MAX

#define MX6_UFCR_TXTL_MAX   32

MX6_UFCR_TXTL_SHIFT

#define MX6_UFCR_TXTL_SHIFT   10

MX6_USR1_AGTIM_MASK

#define MX6_USR1_AGTIM_MASK   (1 << 8)

MX6_USR1_AIRINT_MASK

#define MX6_USR1_AIRINT_MASK   (1 << 5)

MX6_USR1_AWAKE_MASK

#define MX6_USR1_AWAKE_MASK   (1 << 4)

MX6_USR1_DTRD_MASK

#define MX6_USR1_DTRD_MASK   (1 << 7)

MX6_USR1_ESCF_MASK

#define MX6_USR1_ESCF_MASK   (1 << 11)

MX6_USR1_FRMER_MASK

#define MX6_USR1_FRMER_MASK   (1 << 10)

MX6_USR1_PRTERRY_MASK

#define MX6_USR1_PRTERRY_MASK   (1 << 15)

MX6_USR1_TRDY

#define MX6_USR1_TRDY   (1 << 13)

MX6_USR2_RDR

#define MX6_USR2_RDR   (1 << 0)

MX6_USR2_RDRDY_MASK

#define MX6_USR2_RDRDY_MASK   1

MX6_UTS_RXEMPTY_MASK

#define MX6_UTS_RXEMPTY_MASK   (1 << 5)

Typedef Documentation

MX6_UART_REGISTERS

typedef struct _MX6_UART_REGISTERS MX6_UART_REGISTERS

PMX6_UART_REGISTERS

typedef struct _MX6_UART_REGISTERS * PMX6_UART_REGISTERS

Function Documentation

C_ASSERT()

C_ASSERT

(

FIELD_OFFSET(MX6_UART_REGISTERS, Umcr)

= =0xB8

)

MX6GetByte()

UART_STATUS MX6GetByte	(	_Inout_ PCPPORT	Port,
		_Out_ PUCHAR	Byte )

{
    volatile PMX6_UART_REGISTERS Registers;
    ULONG                        RxdReg;
 
    if ((Port == NULL) || (Port->Address == NULL))
    {
        return UartNotReady;
    }
 
    Registers = (PMX6_UART_REGISTERS)Port->Address;
 
    //
    // Read an entry from the RX FIFO.
    //
 
    RxdReg = READ_REGISTER_ULONG(&Registers->Rxd);
 
    //
    // Check if the entry is valid (i.e. was a byte actually received).
    //
 
    if ((RxdReg & MX6_RXD_CHARRDY) == 0)
    {
        return UartNoData;
    }
 
    //
    // Check if an error occurred.
    //
 
    if ((RxdReg & MX6_RXD_ERR) != 0)
    {
        return UartError;
    }
 
    //
    // Mask off the data and return it
    //
 
    *Byte = (UCHAR)(RxdReg & MX6_RXD_DATA_MASK);
    return UartSuccess;
}

MX6InitializePort()

BOOLEAN MX6InitializePort	(	_In_opt_ _Null_terminated_ PCHAR	LoadOptions,
		_Inout_ PCPPORT	Port,
		BOOLEAN	MemoryMapped,
		UCHAR	AccessSize,
		UCHAR	BitWidth )

{
    volatile PMX6_UART_REGISTERS Registers;
    ULONG                        Ucr1Reg;
    ULONG                        Ucr2Reg;
    ULONG                        UfcrReg;
 
    UNREFERENCED_PARAMETER(LoadOptions);
    UNREFERENCED_PARAMETER(AccessSize);
    UNREFERENCED_PARAMETER(BitWidth);
 
    if (MemoryMapped == FALSE)
    {
        return FALSE;
    }
 
    Registers = (PMX6_UART_REGISTERS)Port->Address;
 
    //
    // Verify UART is enabled. UEFI should have enabled the UART.
    //
 
    Ucr1Reg = READ_REGISTER_ULONG(&Registers->Ucr1);
    if ((Ucr1Reg & MX6_UCR1_UARTEN) == 0)
    {
        return FALSE;
    }
 
    //
    // Verify transmitter and receiver are enabled. These must be enabled
    // or else writing to the RXD and TXD registers will cause a bus error.
    //
 
    Ucr2Reg = READ_REGISTER_ULONG(&Registers->Ucr2);
    if (((Ucr2Reg & MX6_UCR2_TXEN) == 0) ||
        ((Ucr2Reg & MX6_UCR2_RXEN) == 0))
    {
        return FALSE;
    }
 
    //
    // Configure transmitter trigger level to maximum.
    //
 
    UfcrReg = READ_REGISTER_ULONG(&Registers->Ufcr);
    UfcrReg = (UfcrReg & ~MX6_UFCR_TXTL_MASK) |
              (MX6_UFCR_TXTL_MAX << MX6_UFCR_TXTL_SHIFT);
 
    WRITE_REGISTER_ULONG(&Registers->Ufcr, UfcrReg);
    return TRUE;
}

MX6PutByte()

UART_STATUS MX6PutByte	(	_Inout_ PCPPORT	Port,
		UCHAR	Byte,
		BOOLEAN	BusyWait )

{
    volatile PMX6_UART_REGISTERS Registers;
    ULONG                        Usr1Reg;
 
    if ((Port == NULL) || (Port->Address == NULL))
    {
        return UartNotReady;
    }
 
    Registers = (PMX6_UART_REGISTERS)Port->Address;
 
    //
    // Wait for the transmit interface to be ready (TRDY bit HIGH).
    //
 
    if (BusyWait != FALSE)
    {
        do
        {
            Usr1Reg = READ_REGISTER_ULONG(&Registers->Usr1);
        } while ((Usr1Reg & MX6_USR1_TRDY) == 0);
    }
    else
    {
        Usr1Reg = READ_REGISTER_ULONG(&Registers->Usr1);
        if ((Usr1Reg & MX6_USR1_TRDY) == 0)
        {
            return UartNotReady;
        }
    }
 
    //
    // Send the byte.
    //
 
    WRITE_REGISTER_ULONG(&Registers->Txd, Byte);
    return UartSuccess;
}

MX6RxReady()

BOOLEAN MX6RxReady

(

_Inout_ PCPPORT

Port

)

{
    volatile PMX6_UART_REGISTERS Registers;
    ULONG                        Usr2Reg;
 
    if ((Port == NULL) || (Port->Address == NULL))
    {
        return FALSE;
    }
 
    Registers = (PMX6_UART_REGISTERS)Port->Address;
 
    //
    // Return TRUE if the "Receive Data Ready" bit is set
    //
 
    Usr2Reg = READ_REGISTER_ULONG(&Registers->Usr2);
    return (Usr2Reg & MX6_USR2_RDR) != 0;
}

MX6SetBaud()

BOOLEAN MX6SetBaud	(	_Inout_ PCPPORT	Port,
		ULONG	Rate )

{
    if ((Port == NULL) || (Port->Address == NULL))
    {
        return FALSE;
    }
 
    //
    // Remember the baud rate.
    //
 
    Port->BaudRate = Rate;
    return FALSE;
}

Variable Documentation

MX6HardwareDriver

UART_HARDWARE_DRIVER MX6HardwareDriver

Initial value:

= {
    MX6InitializePort,
    MX6SetBaud,
    MX6GetByte,
    MX6PutByte,
    MX6RxReady}

                                         {
    MX6InitializePort,
    MX6SetBaud,
    MX6GetByte,
    MX6PutByte,
    MX6RxReady};