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- Cleanup the arbitration

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- Make sure the MON_BUSY flag is cleared after a DMA transfer. Otherwise
  we might end up with a 'lost-busy' situation unexpectedly. This will
  prevent the 5380 from driving the bus, which is not funny during
  reselections.
This commit is contained in:
leo 1995-10-08 13:34:23 +00:00
parent 5510303680
commit 0e5fe20560
1 changed files with 47 additions and 47 deletions
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94
sys/arch/atari/dev/ncr5380.c
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@ -1,4 +1,4 @@
/* $NetBSD: ncr5380.c,v 1.10 1995/10/05 08:52:58 leo Exp $ */
/* $NetBSD: ncr5380.c,v 1.11 1995/10/08 13:34:23 leo Exp $ */
/*
* Copyright (c) 1995 Leo Weppelman.
@ -711,7 +711,7 @@ SC_REQ *reqp;
* Interrupts are lowered when the 5380 is setup to arbitrate for the
* bus.
*/
if (connected || (GET_5380_REG(NCR5380_IDSTAT) & SC_S_BSY)) {
if (connected) {
splx(sps);
PID("scsi_select2");
return (-1);
@ -732,34 +732,15 @@ SC_REQ *reqp;
splx(sps);
cnt = 10000;
cnt = 10;
while (!(GET_5380_REG(NCR5380_ICOM) & SC_AIP) && --cnt)
delay(1);
if (!(GET_5380_REG(NCR5380_ICOM) & SC_AIP)) {
SET_5380_REG(NCR5380_MODE, IMODE_BASE);
delay(1);
SET_5380_REG(NCR5380_ICOM, 0);
DBG_SELPRINT ("Arbitration lost, bus not free\n",0);
PID("scsi_select3");
if (GET_5380_REG(NCR5380_IDSTAT) & SC_S_BSY) {
/*
* Damn, we have a connected target that we don't know
* of. Some targets seem to respond to a selection
* AFTER the selection-timeout. Try to get the target
* into the Message-out phase so we can send an ABORT
* message. We try to avoid resetting the SCSI-bus!
*/
if (!reach_msg_out(sc, sizeof(struct scsi_generic))) {
u_long len = 1;
u_char phase = PH_MSGOUT;
u_char msg = MSG_ABORT;
transfer_pio(&phase, &msg, &len, 0);
}
else if (GET_5380_REG(NCR5380_IDSTAT) & SC_S_BSY)
scsi_reset(sc);
}
PID("scsi_select4");
return (-1);
}
@ -770,36 +751,47 @@ SC_REQ *reqp;
* Check the result of the arbitration. If we failed, return -1.
*/
if (GET_5380_REG(NCR5380_ICOM) & SC_LA) {
/*
* The spec requires that we should read the data register to
* check for higher id's and check the SC_LA again.
*/
tmp[0] = GET_5380_REG(NCR5380_DATA);
if (GET_5380_REG(NCR5380_ICOM) & SC_LA) {
SET_5380_REG(NCR5380_MODE, IMODE_BASE);
SET_5380_REG(NCR5380_ICOM, 0);
DBG_SELPRINT ("Arbitration lost,deassert SC_ARBIT\n",0);
PID("scsi_select5");
return (-1);
}
SET_5380_REG(NCR5380_MODE, IMODE_BASE);
SET_5380_REG(NCR5380_ICOM, 0);
PID("scsi_select4");
return (-1);
}
/*
* The spec requires that we should read the data register to
* check for higher id's and check the SC_LA again.
*/
tmp[0] = GET_5380_REG(NCR5380_DATA);
if (tmp[0] & ~((SC_HOST_ID << 1) - 1)) {
SET_5380_REG(NCR5380_MODE, IMODE_BASE);
SET_5380_REG(NCR5380_ICOM, 0);
DBG_SELPRINT ("Arbitration lost, higher id present\n",0);
PID("scsi_select5");
return (-1);
}
if (GET_5380_REG(NCR5380_ICOM) & SC_LA) {
SET_5380_REG(NCR5380_MODE, IMODE_BASE);
SET_5380_REG(NCR5380_ICOM, 0);
DBG_SELPRINT ("Arbitration lost,deassert SC_ARBIT\n",0);
PID("scsi_select6");
return (-1);
}
SET_5380_REG(NCR5380_ICOM, SC_A_SEL | SC_A_BSY);
if (GET_5380_REG(NCR5380_ICOM) & SC_LA) {
SET_5380_REG(NCR5380_MODE, IMODE_BASE);
SET_5380_REG(NCR5380_ICOM, 0);
DBG_SELPRINT ("Arbitration lost, deassert SC_A_SEL\n", 0);
PID("scsi_select6");
PID("scsi_select7");
return (-1);
}
/* Bus settle delay + Bus clear delay = 1.2 usecs */
delay(2);
DBG_SELPRINT ("Arbitration complete\n", 0);
targ_bit = 1 << reqp->targ_id;
/*
* Now that we won the arbitration, start the selection.
*/
targ_bit = 1 << reqp->targ_id;
SET_5380_REG(NCR5380_DATA, SC_HOST_ID | targ_bit);
if (sc->sc_noselatn & targ_bit)
@ -832,7 +824,7 @@ SC_REQ *reqp;
* Wait for the target to react, the specs call for a timeout of
* 250 ms.
*/
cnt = 25000 /* 250 */;
cnt = 25000;
while (!(GET_5380_REG(NCR5380_IDSTAT) & SC_S_BSY) && --cnt)
delay(10);
@ -845,7 +837,7 @@ SC_REQ *reqp;
* When BSY is asserted, we assume the selection succeeded,
* otherwise we release the bus.
*/
SET_5380_REG(NCR5380_ICOM, SC_A_SEL | SC_A_ATN);
SET_5380_REG(NCR5380_ICOM, SC_A_SEL | atn_flag);
delay(201);
if (!(GET_5380_REG(NCR5380_IDSTAT) & SC_S_BSY)) {
SET_5380_REG(NCR5380_ICOM, 0);
@ -853,7 +845,7 @@ SC_REQ *reqp;
DBG_SELPRINT ("Target %d not responding to sel\n",
reqp->targ_id);
finish_req(reqp);
PID("scsi_select7");
PID("scsi_select8");
return (0);
}
}
@ -921,7 +913,7 @@ SC_REQ *reqp;
SET_5380_REG(NCR5380_ICOM, 0);
reqp->xs->error = code ? code : XS_DRIVER_STUFFUP;
finish_req(reqp);
PID("scsi_select8");
PID("scsi_select9");
return (0);
}
reqp->phase = PH_MSGOUT;
@ -938,7 +930,7 @@ identify_failed:
connected = reqp;
busy |= targ_bit;
PID("scsi_select9");
PID("scsi_select10");
return (0);
}
@ -986,7 +978,6 @@ information_transfer()
switch (phase) {
case PH_DATAOUT:
#ifdef DBG_NOWRITE
ncr_tprint(reqp, "NOWRITE set -- write attempt aborted.");
reqp->msgout = MSG_ABORT;
@ -1198,6 +1189,13 @@ struct ncr_softc *sc;
SET_5380_REG(NCR5380_ICOM, SC_A_BSY);
len = 1000;
while ((GET_5380_REG(NCR5380_IDSTAT) & SC_S_SEL) && (len > 0)) {
if(!GET_5380_REG(NCR5380_DATA)) {
/*
* We stepped into the reselection timeout....
*/
SET_5380_REG(NCR5380_ICOM, 0);
return;
}
delay(1);
len--;
}
@ -1457,9 +1455,11 @@ dma_ready()
/*
* DMA mode should always be reset even when we will continue with the
* next chain.
* next chain. It is also essential to clear the MON_BUSY because
* when LOST_BUSY is unexpectedly set, we will not be able to drive
* the bus....
*/
SET_5380_REG(NCR5380_MODE, GET_5380_REG(NCR5380_MODE) & ~SC_M_DMA);
SET_5380_REG(NCR5380_MODE, IMODE_BASE);
if ((dmstat & SC_BSY_ERR) || !(dmstat & SC_PHS_MTCH)