at91uart.c

包含makefile config.h rominit romstart userinit 等等文件

/* sndsSio.c - Samsung SNDS100 serial driver */

/*
modification history
--------------------
*/

/*
DESCRIPTION

INCLUDES:
sndsSio.h sioLib.h
*/

#include "sioLib.h"
#include "intLib.h"
#include "errno.h"
#include "ioLib.h"


#define AT91UART_BAUD_MIN	1200
#define AT91UART_BAUD_MAX	460800
							
/* for backward compatibility */

#ifndef	SIO_HUP
#   define SIO_OPEN	0x100A	/* open channel, raise DTR, RTS */
#   define SIO_HUP	0x100B	/* hang-up, lower DTR, RTS */
#endif

/* forward static declarations */

LOCAL int	AT91UartTxStartup (SIO_CHAN * pSioChan);
LOCAL int	AT91UartCallbackInstall (SIO_CHAN *pSioChan, int callbackType,
				    STATUS (*callback)(), void *callbackArg);
LOCAL int	AT91UartPollOutput (SIO_CHAN *pSioChan, char	outChar);
LOCAL int	AT91UartPollInput (SIO_CHAN *pSioChan, char *thisChar);
LOCAL int	AT91UartIoctl (SIO_CHAN *pSioChan, int request, void *arg );


/* local variables */

LOCAL	SIO_DRV_FUNCS AT91UartDrvFuncs =
{
    AT91UartIoctl,
    AT91UartTxStartup,
    AT91UartCallbackInstall,
    AT91UartPollInput,
    AT91UartPollOutput,
};



/******************************************************************************
*
* AT91DevInit - initialize a SNDS_DUSART
*
* This routine initializes the driver
* function pointers and then resets the chip in a quiescent state.
* The BSP must have already initialized all the device addresses and the
* baudFreq fields in the SNDS_DUSART structure before passing it to
* this routine.
*
* RETURNS: N/A
*/

void AT91UartDevInit
(
    AT91_CHAN * pChan
)
{
    UINT32 dummy;
	/* initialize each channel's driver function pointers */
    int oldlevel;
	
    pChan->sio.pDrvFuncs	= &AT91UartDrvFuncs;

    /* install dummy driver callbacks */

    pChan->getTxChar    = dummyCallback;
    pChan->putRcvChar	= dummyCallback;
    
    /* reset the chip */
	 oldlevel = intLock ();
	
    pChan->regs->US_CR = UART_CR_RESET_RECV | UART_CR_RESET_TRAN | UART_CR_RX_DIS | UART_CR_TX_DIS;
	pChan->regs->US_MR = UART_MR_CHAR_8BIT | UART_MR_STOP_1BIT | UART_MR_PARITY_NONE
				| UART_MR_CLK_USE_MCK | UART_MR_TEST_NORMAL_MODE| UART_MR_UART_MODE_NORMAL;
	/*
	 *	disable all interrupt source first
	 */
	pChan->regs->US_IDR = 0xFFFFFFFF;
	pChan->regs->US_TTGR = UART_TANS_TIME_GUARD;
	dummy = pChan ->regs->US_RHR;
    intUnlock ( oldlevel );
	pChan->intrmode = FALSE;
	
	/*
	 *	Init PDC, disable all pdc function
	 */
	AT91_PDC_Close( &(pChan->regs->US_PDC) );
	/*
	 *	make a dummy read emtpy the receive buf
	 */
	
    /* setting polled mode is one way to make the device quiet */
	AT91UartIoctl ( (SIO_CHAN *)pChan, SIO_BAUD_SET, (void *)pChan->baudRate );
    AT91UartIoctl ( (SIO_CHAN *)pChan, SIO_MODE_SET,(void *)SIO_MODE_POLL );

	pChan->regs->US_CR = UART_CR_RX_ENA | UART_CR_TX_DIS | UART_CR_RESET_STATUS;
}

/******************************************************************************
*
* sndsDevInit2 - initialize a SNDS_DUSART, part 2
*
* This routine is called by the BSP after interrupts have been connected.
* The driver can now operate in interrupt mode.  Before this routine is
* called only polled mode operations should be allowed.
*
* RETURNS: N/A
* ARGSUSED
*/

void AT91UartDevInit2
    (
    AT91_CHAN * pChan		/* device to initialize */
    )
{
	pChan ->errcount = 0;
	pChan->regs->US_CR = UART_CR_RX_ENA | UART_CR_TX_DIS | UART_CR_RESET_STATUS;
	/*
	 *	enable UART interrupt now.
	 */
    pChan->regs->US_IER = UART_IE_DR_TXRDY | UART_IE_DR_RXRDY | UART_IE_DR_FRAME 
					| UART_IE_DR_PARE| UART_IE_DR_OVRE;

	pChan->intrmode = TRUE;
}

/******************************************************************************
*
* sndsIntRcv - handle a channel's receive-character interrupt
*
* RETURNS: N/A
*/ 

void AT91UartInt
    (
    AT91_CHAN *	pChan		/* channel generating the interrupt */
    )
{
    
	char outchar;
	UINT32	    status;

	UART_S* udev = pChan ->regs;
	
	status = udev->US_CSR;
	if( status&( UART_CSR_FRAME | UART_CSR_OVRE| UART_CSR_PARE ) )
	{
		pChan->errcount ++;
		udev->US_CR = UART_CR_RESET_STATUS;
	}

	if( status&(UART_CSR_RXRDY ) )
	{
		(*pChan->putRcvChar) ( pChan->putRcvArg, udev ->US_RHR );
	}

	if( status&( UART_CSR_TXRDY ) )
	{
		if( (*pChan->getTxChar) (pChan->getTxArg, &outchar) != ERROR )
		{
			udev ->US_THR = (AT91_REG)(outchar);
		}
		else
		{
			udev ->US_CR = UART_CR_TX_DIS;
		}
	}
}


/******************************************************************************
*
* sndsTxStartup - start the interrupt transmitter
*
* RETURNS: OK on success, ENOSYS if the device is polled-only, or
* EIO on hardware error.
*/

LOCAL int AT91UartTxStartup
    (
    SIO_CHAN * pSioChan                 /* channel to start */
    )
{
    AT91_CHAN * pChan = (AT91_CHAN *)pSioChan;
	
	if( pChan ->intrmode == TRUE )
	{
		pChan ->regs->US_CR = UART_CR_TX_ENA;
		return OK;
	}
	else 
		return ENOSYS;
}

/******************************************************************************
*
* sndsCallbackInstall - install ISR callbacks to get/put chars
*
* This driver allows interrupt callbacks for transmitting characters
* and receiving characters. In general, drivers may support other
* types of callbacks too.
*
* RETURNS: OK on success, or ENOSYS for an unsupported callback type.
*/ 

LOCAL int AT91UartCallbackInstall
    (
    SIO_CHAN *	pSioChan,               /* channel */
    int		callbackType,           /* type of callback */
    STATUS	(*callback)(),          /* callback */
    void *      callbackArg             /* parameter to callback */
    )
{
    AT91_CHAN * pChan = (AT91_CHAN *)pSioChan;
    switch (callbackType)
	{
	case SIO_CALLBACK_GET_TX_CHAR:
	    pChan->getTxChar	= callback;
	    pChan->getTxArg	= callbackArg;
	    return (OK);

	case SIO_CALLBACK_PUT_RCV_CHAR:
	    pChan->putRcvChar	= callback;
	    pChan->putRcvArg	= callbackArg;
	    return (OK);

	default:
	    return (ENOSYS);
	}
}

/*******************************************************************************
*
* sndsPollOutput - output a character in polled mode
*
* RETURNS: OK if a character arrived, EIO on device error, EAGAIN
* if the output buffer if full. ENOSYS if the device is
* interrupt-only.
*/

LOCAL int AT91UartPollOutput
    (
    SIO_CHAN *	pSioChan,
    char	outChar
    )
{
    AT91_CHAN * pChan = (AT91_CHAN *)pSioChan;
    UART_S* udev;
	UINT32	status;

	udev = pChan ->regs;
    /* is the transmitter ready to accept a character? */
	status = udev ->US_CSR;

	if( status&( UART_CSR_FRAME | UART_CSR_OVRE| UART_CSR_PARE ) )
	{
		pChan->errcount ++;
		udev->US_CR = UART_CR_RESET_STATUS;
	}

	if( status&(UART_CSR_TXRDY) )
	{
		udev ->US_THR = (AT91_REG)(outChar);
		return (OK);
	}
	else
		return (EAGAIN);
}

/******************************************************************************
*
* sndsPollInput - poll the device for input
*
* RETURNS: OK if a character arrived, EIO on device error, EAGAIN
* if the input buffer if empty, ENOSYS if the device is
* interrupt-only.
*/

LOCAL int AT91UartPollInput
    (
    SIO_CHAN *	pSioChan,
    char *	thisChar
    )
{
    AT91_CHAN * pChan = (AT91_CHAN *)pSioChan;
    UART_S* udev;
	UINT32	status;
	
	udev = pChan ->regs;
	status = udev ->US_CSR;
	
	if( status&( UART_CSR_FRAME | UART_CSR_OVRE| UART_CSR_PARE ) )
	{
		pChan->errcount ++;
		udev->US_CR = UART_CR_RESET_STATUS;
	}
	
	if( status&(UART_CSR_RXRDY) )
	{
		status = udev ->US_RHR;
		(*thisChar) = (BYTE)status;
	    return (OK);
    }
	else
		return (EAGAIN);
}
/******************************************************************************
*
* sndsModeSet - toggle between interrupt and polled mode
*
* RETURNS: OK on success, EIO on unsupported mode.
*/

LOCAL int At91UartModeSet
    (
    AT91_CHAN * pChan,		/* channel */
    int	newMode        	/* new mode */
    )
{
    UINT32	temp;
    if ( (newMode != SIO_MODE_POLL) && (newMode != SIO_MODE_INT) )	
		return (EIO);


    /* Don't enter interrupt mode unless it is allowed. */

    if ( (newMode == SIO_MODE_INT) && ( pChan ->intrmode ) )
		return (EIO);

    /* set the new mode */
	if( newMode == SIO_MODE_INT )
		pChan->intrmode = TRUE;
	else
		pChan->intrmode = FALSE;


    if ( pChan->intrmode )
	{
		/*
		 *	TX int still not enabled
		 */
		pChan->regs->US_CR = UART_CR_RX_ENA | UART_CR_TX_DIS | UART_CR_RESET_STATUS;
		pChan->regs->US_IER = UART_IE_DR_TXRDY | UART_IE_DR_RXRDY | UART_IE_DR_FRAME 
			| UART_IE_DR_PARE| UART_IE_DR_OVRE;
		intEnable( pChan ->level );
	}
	else