/***************************************************************************
Function: sFlushTxFIFO
Purpose: Flush the Tx FIFO
Call: sFlushTxFIFO(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 sFlushTxFIFO(CHANNEL_T *ChP)
{
int i;
Byte_t Ch; /* channel number within AIOP */
int TxEnabled; /* TRUE if transmitter enabled */
if(sGetTxCnt(ChP) == 0) /* Tx FIFO empty */
return; /* don't need to flush */
TxEnabled = FALSE;
if(ChP->TxControl[3] & TX_ENABLE)
{
TxEnabled = TRUE;
sDisTransmit(ChP); /* disable transmitter */
}
sStopRxProcessor(ChP); /* stop Rx processor */
for(i = 0; i < 4000/200; i++) /* delay 4 uS to allow proc to stop */
rp_readch1(ChP,_INT_CHAN); /* depends on bus i/o timing */
Ch = (Byte_t)sGetChanNum(ChP);
rp_writech1(ChP,_CMD_REG,Ch | RESTXFCNT); /* apply reset Tx FIFO count */
rp_writech1(ChP,_CMD_REG,Ch); /* remove reset Tx FIFO count */
rp_writech2(ChP,_INDX_ADDR,ChP->TxFIFOPtrs); /* clear Tx in/out ptrs */
rp_writech2(ChP,_INDX_DATA,0);
if(TxEnabled)
sEnTransmit(ChP); /* enable transmitter */
sStartRxProcessor(ChP); /* restart Rx processor */
}
/***************************************************************************
Function: sWriteTxPrioByte
Purpose: Write a byte of priority transmit data to a channel
Call: sWriteTxPrioByte(ChP,Data)
CHANNEL_T *ChP; Ptr to channel structure
Byte_t Data; The transmit data byte
Return: int: 1 if the bytes is successfully written, otherwise 0.
Comments: The priority byte is transmitted before any data in the Tx FIFO.
Warnings: No context switches are allowed while executing this function.
*/
int sWriteTxPrioByte(CHANNEL_T *ChP, Byte_t Data)
{
Byte_t DWBuf[4]; /* buffer for double word writes */
if(sGetTxCnt(ChP) > 1) /* write it to Tx priority buffer */
{
rp_writech2(ChP,_INDX_ADDR,ChP->TxPrioCnt); /* get priority buffer status */
if(rp_readch1(ChP,_INDX_DATA) & PRI_PEND) /* priority buffer busy */
return(0); /* nothing sent */
le16enc(DWBuf,ChP->TxPrioBuf); /* data byte address */
DWBuf[2] = Data; /* data byte value */
DWBuf[3] = 0; /* priority buffer pointer */
rp_writech4(ChP,_INDX_ADDR,le32dec(DWBuf)); /* write it out */
le16enc(DWBuf,ChP->TxPrioCnt); /* Tx priority count address */
DWBuf[2] = PRI_PEND + 1; /* indicate 1 byte pending */
DWBuf[3] = 0; /* priority buffer pointer */
rp_writech4(ChP,_INDX_ADDR,le32dec(DWBuf)); /* write it out */
}
else /* write it to Tx FIFO */
{
sWriteTxByte(ChP,sGetTxRxDataIO(ChP),Data);
}
return(1); /* 1 byte sent */
}
/***************************************************************************
Function: sWriteTxPrioByte
Purpose: Write a byte of priority transmit data to a channel
Call: sWriteTxPrioByte(ChP,Data)
CHANNEL_T *ChP; Ptr to channel structure
Byte_t Data; The transmit data byte
Return: int: 1 if the bytes is successfully written, otherwise 0.
Comments: The priority byte is transmitted before any data in the Tx FIFO.
Warnings: No context switches are allowed while executing this function.
*/
int sWriteTxPrioByte(CHANNEL_T *ChP, Byte_t Data)
{
Byte_t DWBuf[4]; /* buffer for double word writes */
Word_t *WordPtr; /* must be far because Win SS != DS */
crit_enter();
if(sGetTxCnt(ChP) > 1) /* write it to Tx priority buffer */
{
rp_writech2(ChP,_INDX_ADDR,ChP->TxPrioCnt); /* get priority buffer status */
if(rp_readch1(ChP,_INDX_DATA) & PRI_PEND) {/* priority buffer busy */
crit_exit();
return(0); /* nothing sent */
}
WordPtr = (Word_t *)(&DWBuf[0]);
*WordPtr = ChP->TxPrioBuf; /* data byte address */
DWBuf[2] = Data; /* data byte value */
rp_writech4(ChP,_INDX_ADDR,*((DWord_t *)(&DWBuf[0]))); /* write it out */
*WordPtr = ChP->TxPrioCnt; /* Tx priority count address */
DWBuf[2] = PRI_PEND + 1; /* indicate 1 byte pending */
DWBuf[3] = 0; /* priority buffer pointer */
rp_writech4(ChP,_INDX_ADDR,*((DWord_t *)(&DWBuf[0]))); /* write it out */
}
else /* write it to Tx FIFO */
{
sWriteTxByte(ChP,sGetTxRxDataIO(ChP),Data);
}
crit_exit();
return(1); /* 1 byte sent */
}
static void rp_do_poll(void *not_used)
{
CONTROLLER_t *ctl;
struct rp_port *rp;
struct tty *tp;
int unit, aiop, ch, line, count;
unsigned char CtlMask, AiopMask;
for(unit = 0; unit < rp_ndevs; unit++) {
rp = rp_addr(unit);
ctl = rp->rp_ctlp;
CtlMask = ctl->ctlmask(ctl);
for(aiop=0; CtlMask; CtlMask >>=1, aiop++) {
if(CtlMask & 1) {
AiopMask = sGetAiopIntStatus(ctl, aiop);
for(ch = 0; AiopMask; AiopMask >>=1, ch++) {
if(AiopMask & 1) {
line = (unit << 5) | (aiop << 3) | ch;
rp = rp_table(line);
rp_handle_port(rp);
}
}
}
}
for(line = 0, rp = rp_addr(unit); line < rp_num_ports[unit];
line++, rp++) {
tp = rp->rp_tty;
tty_lock(tp);
count = sGetTxCnt(&rp->rp_channel);
if (count >= 0 &&
(count <= rp->rp_restart)) {
rpstart(tp);
}
tty_unlock(tp);
}
}
