/***************************************************************************
Function: sFlushRxFIFO
Purpose: Flush the Rx FIFO
Call: sFlushRxFIFO(ChP)
CHANNEL_T *ChP; Ptr to channel structure
Return: void
Comments: To prevent data from being enqueued or dequeued in the Tx FIFO
while it is being flushed the receive processor is stopped
and the transmitter is disabled. After these operations a
4 uS delay is done before clearing the pointers to allow
the receive processor to stop. These items are handled inside
this function.
Warnings: No context switches are allowed while executing this function.
*/
void sFlushRxFIFO(CHANNEL_T *ChP)
{
int i;
Byte_t Ch; /* channel number within AIOP */
int RxFIFOEnabled; /* TRUE if Rx FIFO enabled */
if(sGetRxCnt(ChP) == 0) /* Rx FIFO empty */
return; /* don't need to flush */
RxFIFOEnabled = FALSE;
if(ChP->R[0x32] == 0x08) /* Rx FIFO is enabled */
{
RxFIFOEnabled = TRUE;
sDisRxFIFO(ChP); /* disable it */
for(i=0; i < 2000/200; i++) /* delay 2 uS to allow proc to disable FIFO*/
rp_readch1(ChP,_INT_CHAN); /* depends on bus i/o timing */
}
sGetChanStatus(ChP); /* clear any pending Rx errors in chan stat */
Ch = (Byte_t)sGetChanNum(ChP);
rp_writech1(ChP,_CMD_REG,Ch | RESRXFCNT); /* apply reset Rx FIFO count */
rp_writech1(ChP,_CMD_REG,Ch); /* remove reset Rx FIFO count */
rp_writech2(ChP,_INDX_ADDR,ChP->RxFIFOPtrs); /* clear Rx out ptr */
rp_writech2(ChP,_INDX_DATA,0);
rp_writech2(ChP,_INDX_ADDR,ChP->RxFIFOPtrs + 2); /* clear Rx in ptr */
rp_writech2(ChP,_INDX_DATA,0);
if(RxFIFOEnabled)
sEnRxFIFO(ChP); /* enable Rx FIFO */
}
static void rp_do_receive(struct rp_port *rp, struct tty *tp,
CHANNEL_t *cp, unsigned int ChanStatus)
{
unsigned int CharNStat;
int ToRecv, ch, err = 0;
ToRecv = sGetRxCnt(cp);
if(ToRecv == 0)
return;
/* If status indicates there are errored characters in the
FIFO, then enter status mode (a word in FIFO holds
characters and status)
*/
if(ChanStatus & (RXFOVERFL | RXBREAK | RXFRAME | RXPARITY)) {
if(!(ChanStatus & STATMODE)) {
ChanStatus |= STATMODE;
sEnRxStatusMode(cp);
}
}
/*
if we previously entered status mode then read down the
FIFO one word at a time, pulling apart the character and
the status. Update error counters depending on status.
*/
tty_lock(tp);
if(ChanStatus & STATMODE) {
while(ToRecv) {
CharNStat = rp_readch2(cp,sGetTxRxDataIO(cp));
ch = CharNStat & 0xff;
if((CharNStat & STMBREAK) || (CharNStat & STMFRAMEH))
err |= TRE_FRAMING;
else if (CharNStat & STMPARITYH)
err |= TRE_PARITY;
else if (CharNStat & STMRCVROVRH) {
rp->rp_overflows++;
err |= TRE_OVERRUN;
}
ttydisc_rint(tp, ch, err);
ToRecv--;
}
/*
After emtying FIFO in status mode, turn off status mode
*/
if(sGetRxCnt(cp) == 0) {
sDisRxStatusMode(cp);
}
} else {
ToRecv = sGetRxCnt(cp);
while (ToRecv) {
ch = rp_readch1(cp,sGetTxRxDataIO(cp));
ttydisc_rint(tp, ch & 0xff, err);
ToRecv--;
}
}
ttydisc_rint_done(tp);
tty_unlock(tp);
}
/*
* NOTE: Must be called with tty_token held
*/
static void
rp_do_receive(struct rp_port *rp, struct tty *tp,
CHANNEL_t *cp, unsigned int ChanStatus)
{
unsigned int CharNStat;
int ToRecv, wRecv, ch, ttynocopy;
ASSERT_LWKT_TOKEN_HELD(&tty_token);
ToRecv = sGetRxCnt(cp);
if(ToRecv == 0)
return;
/* If status indicates there are errored characters in the
FIFO, then enter status mode (a word in FIFO holds
characters and status)
*/
if(ChanStatus & (RXFOVERFL | RXBREAK | RXFRAME | RXPARITY)) {
if(!(ChanStatus & STATMODE)) {
ChanStatus |= STATMODE;
sEnRxStatusMode(cp);
}
}
/*
if we previously entered status mode then read down the
FIFO one word at a time, pulling apart the character and
the status. Update error counters depending on status.
*/
if(ChanStatus & STATMODE) {
while(ToRecv) {
if(tp->t_state & TS_TBLOCK) {
break;
}
CharNStat = rp_readch2(cp,sGetTxRxDataIO(cp));
ch = CharNStat & 0xff;
if((CharNStat & STMBREAK) || (CharNStat & STMFRAMEH))
ch |= TTY_FE;
else if (CharNStat & STMPARITYH)
ch |= TTY_PE;
else if (CharNStat & STMRCVROVRH)
rp->rp_overflows++;
(*linesw[tp->t_line].l_rint)(ch, tp);
ToRecv--;
}
/*
After emtying FIFO in status mode, turn off status mode
*/
if(sGetRxCnt(cp) == 0) {
sDisRxStatusMode(cp);
}
} else {
/*
* Avoid the grotesquely inefficient lineswitch routine
* (ttyinput) in "raw" mode. It usually takes about 450
* instructions (that's without canonical processing or echo!).
* slinput is reasonably fast (usually 40 instructions plus
* call overhead).
*/
ToRecv = sGetRxCnt(cp);
if ( tp->t_state & TS_CAN_BYPASS_L_RINT ) {
if ( ToRecv > RXFIFO_SIZE ) {
ToRecv = RXFIFO_SIZE;
}
wRecv = ToRecv >> 1;
if ( wRecv ) {
rp_readmultich2(cp,sGetTxRxDataIO(cp),(u_int16_t *)rp->RxBuf,wRecv);
}
if ( ToRecv & 1 ) {
((unsigned char *)rp->RxBuf)[(ToRecv-1)] = (u_char) rp_readch1(cp,sGetTxRxDataIO(cp));
}
tk_nin += ToRecv;
tk_rawcc += ToRecv;
tp->t_rawcc += ToRecv;
ttynocopy = b_to_q((char *)rp->RxBuf, ToRecv, &tp->t_rawq);
ttwakeup(tp);
} else {
while (ToRecv) {
if(tp->t_state & TS_TBLOCK) {
break;
}
ch = (u_char) rp_readch1(cp,sGetTxRxDataIO(cp));
crit_enter();
(*linesw[tp->t_line].l_rint)(ch, tp);
crit_exit();
ToRecv--;
}
}
}
