}            else		{                pChan->uart.pSmcReg->smcm = 0;				/* mask off the receive and transmit intrs */		* CIMR(pChan->regBase) &= (~(pChan->uart.intMask));				/* mask off this SMC's interrupt */                 }            pChan->channelMode = arg;            intUnlock(oldlevel);            break;        case SIO_MODE_GET:            * (int *) arg = pChan->channelMode;	    break;        case SIO_AVAIL_MODES_GET:            *(int *)arg = SIO_MODE_INT | SIO_MODE_POLL;	    break;	default:	    status = ENOSYS;	}    return (status);    }/********************************************************************************* ppc860Int - handle an SMC interrupt** This routine is called to handle SMC interrupts.*/void ppc860Int    (    PPC860SMC_CHAN *pChan    )    {    char		outChar;    FAST UINT16		dataLen = 0;    /* check for a receive event */    if (pChan->uart.pSmcReg->smce & SMCE_RX)	{        pChan->uart.pSmcReg->smce = SMCE_RX;	while (!(pChan->uart.rxBdBase [pChan->uart.rxBdNext].statusMode &		 BD_RX_EMPTY_BIT))	    {	    /* process all filled receive buffers */	    outChar = pChan->uart.rxBdBase[pChan->uart.rxBdNext].dataPointer[0];            pChan->uart.rxBdBase[pChan->uart.rxBdNext].statusMode |=                BD_RX_EMPTY_BIT;            /* incr BD count */            pChan->uart.rxBdNext = (pChan->uart.rxBdNext + 1) %                                  pChan->uart.rxBdNum;            /* acknowledge interrupt ??? multiple events ??? */            pChan->uart.pSmcReg->smce = SMCE_RX;	    (*pChan->putRcvChar) (pChan->putRcvArg,outChar);	    if (pChan->channelMode == SIO_MODE_POLL)		break;	    }	}    /* check for a transmit event and if a character needs to be output */    if ((pChan->uart.pSmcReg->smce & SMCE_TX) &&        (pChan->channelMode != SIO_MODE_POLL))	{        pChan->uart.pSmcReg->smce = SMCE_TX;            if ((*pChan->getTxChar) (pChan->getTxArg, &outChar) == OK)	    {	    do	        {	        pChan->uart.txBdBase[pChan->uart.txBdNext].dataPointer[dataLen++]		    = outChar;                if (pChan->channelMode == SIO_MODE_POLL)                    break;	        }	    while ((dataLen < pChan->uart.txBufSize) &&                   ((*pChan->getTxChar) (pChan->getTxArg, &outChar)		       == OK));	    pChan->uart.txBdBase[pChan->uart.txBdNext].dataLength = dataLen;            /* acknowledge interrupt */            pChan->uart.pSmcReg->smce = SMCE_TX;	    /* send transmit buffer */	    pChan->uart.txBdBase[pChan->uart.txBdNext].statusMode |=	        BD_TX_READY_BIT;	    /* incr BD count */ 	    pChan->uart.txBdNext = (pChan->uart.txBdNext+ 1) %							pChan->uart.txBdNum;	    }	}    /* acknowledge all other interrupts - ignore events */    pChan->uart.pSmcReg->smce = (pChan->uart.pSmcReg->smce & 							~(SMCE_RX | SMCE_TX));    * CISR(pChan->regBase) = pChan->uart.intMask;    }/********************************************************************************* ppc860Startup - transmitter startup routine*/static void ppc860Startup    (    PPC860SMC_CHAN *pChan		/* ty device to start up */    )    {    char outChar;    FAST UINT16 dataLen = 0;    if (pChan->channelMode == SIO_MODE_POLL)	return;    /* check if buffer is ready and if a character needs to be output */    if ((!(pChan->uart.txBdBase[pChan->uart.txBdNext].statusMode &	   BD_TX_READY_BIT)) &&        ((*pChan->getTxChar) (pChan->getTxArg, &outChar) == OK))	{	do	    {	    pChan->uart.txBdBase[pChan->uart.txBdNext].dataPointer[dataLen++] =		outChar;	    }	while ((dataLen < pChan->uart.txBufSize) &&               ((*pChan->getTxChar) (pChan->getTxArg, &outChar) == OK));	       						/* fill buffer */	/* send transmit buffer */	pChan->uart.txBdBase[pChan->uart.txBdNext].dataLength  = dataLen;	pChan->uart.txBdBase[pChan->uart.txBdNext].statusMode |=	    BD_TX_READY_BIT;	/* incr BD count */        pChan->uart.txBdNext = (pChan->uart.txBdNext + 1) % pChan->uart.txBdNum;	}    }/******************************************************************************** ppc860PollInput - poll the device for input.** RETURNS: OK if a character arrived, ERROR on device error, EAGAIN*          if the input buffer is empty.*/static int ppc860PollInput    (    SIO_CHAN *	pSioChan,    char *	thisChar    )    {    PPC860SMC_CHAN * pChan = (PPC860SMC_CHAN *) pSioChan;    if (!(pChan->uart.pSmcReg->smce & SMCE_RX))        return (EAGAIN);     if (pChan->uart.rxBdBase[pChan->uart.rxBdNext].statusMode & BD_RX_EMPTY_BIT)        return (EAGAIN);    /* get a character */    *thisChar = pChan->uart.rxBdBase[pChan->uart.rxBdNext].dataPointer[0];    /* set the empty bit */    pChan->uart.rxBdBase[pChan->uart.rxBdNext].statusMode |= BD_RX_EMPTY_BIT;    /* incr BD count */    pChan->uart.rxBdNext = (pChan->uart.rxBdNext + 1) % pChan->uart.rxBdNum;    /* only clear RX event if no more characters are ready */    if (pChan->uart.rxBdBase[pChan->uart.rxBdNext].statusMode & BD_RX_EMPTY_BIT)        pChan->uart.pSmcReg->smce = SMCE_RX;    return (OK);    }/******************************************************************************** ppc860PollOutput - output a character in polled mode.** RETURNS: OK if a character arrived, ERROR on device error, EAGAIN*          if the output buffer if full.*/static int ppc860PollOutput    (    SIO_CHAN *	pSioChan,    char	outChar    )    {    PPC860SMC_CHAN *	pChan = (PPC860SMC_CHAN *) pSioChan;    int			i;    /* wait a bit for the last character to get out */    /* because the PPC604 is a very fast processor */    /* ???  make the 10000 value a #define */    i = 0;    while( (i<10000) && (pChan->uart.txBdBase[pChan->uart.txBdNext].statusMode &	BD_TX_READY_BIT) )	{	i = i + 1;    	}	    /* is the transmitter ready to accept a character? */    /* if still not, we have a problem */    if (pChan->uart.txBdBase[pChan->uart.txBdNext].statusMode &	BD_TX_READY_BIT)	return(EAGAIN);    /* reset the transmitter status bit */    pChan->uart.pSmcReg->smce = SMCE_TX;    /* write out the character */    pChan->uart.txBdBase[pChan->uart.txBdNext].dataPointer[0] = outChar;    pChan->uart.txBdBase[pChan->uart.txBdNext].dataLength  = 1;    /* send transmit buffer */    pChan->uart.txBdBase[pChan->uart.txBdNext].statusMode |= BD_TX_READY_BIT;    pChan->uart.txBdNext = (pChan->uart.txBdNext + 1) % pChan->uart.txBdNum;    return (OK);    }/******************************************************************************** ppc860CallbackInstall - install ISR callbacks to get put chars.**/static int ppc860CallbackInstall    (    SIO_CHAN *	pSioChan,    int		callbackType,    STATUS	(* callback)(),    void *	callbackArg    )    {    PPC860SMC_CHAN * pChan = (PPC860SMC_CHAN *) pSioChan;    switch (callbackType)        {        case SIO_CALLBACK_GET_TX_CHAR:            pChan->getTxChar    = callback;            pChan->getTxArg     = callbackArg;            return (OK);	    break;        case SIO_CALLBACK_PUT_RCV_CHAR:            pChan->putRcvChar   = callback;            pChan->putRcvArg    = callbackArg;            return (OK);	    break;        default:            return (ENOSYS);        }    }