scsincr53c8xx.c

这是一个同样来自贝尔实验室的和UNIX有着渊源的操作系统, 其简洁的设计和实现易于我们学习和理解

#ifdef WMR_DEBUG
	if (inchip) {
		IPRINT(PRINTPREFIX "%d/%d: write_mismatch_recover: DMA FIFO = %d\n",
		    dsa->target, dsa->lun, inchip);
	}
#endif
	if (n->sstat0 & (1 << 5)) {
		inchip++;
#ifdef WMR_DEBUG
		IPRINT(PRINTPREFIX "%d/%d: write_mismatch_recover: SODL full\n", dsa->target, dsa->lun);
#endif
	}
	if (n->sstat2 & (1 << 5)) {
		inchip++;
#ifdef WMR_DEBUG
		IPRINT(PRINTPREFIX "%d/%d: write_mismatch_recover: SODL msb full\n", dsa->target, dsa->lun);
#endif
	}
	if (n->sxfer & SYNCOFFMASK(c)) {
		/* synchronous SODR */
		if (n->sstat0 & (1 << 6)) {
			inchip++;
#ifdef WMR_DEBUG
			IPRINT(PRINTPREFIX "%d/%d: write_mismatch_recover: SODR full\n",
			    dsa->target, dsa->lun);
#endif
		}
		if (n->sstat2 & (1 << 6)) {
			inchip++;
#ifdef WMR_DEBUG
			IPRINT(PRINTPREFIX "%d/%d: write_mismatch_recover: SODR msb full\n",
			    dsa->target, dsa->lun);
#endif
		}
	}
	/* clear the dma fifo */
	n->ctest3 |= (1 << 2);
	/* wait till done */
	while ((n->dstat & Dfe) == 0)
		;
	return dbc + inchip;
}

static void
interrupt(Ureg *ur, void *a)
{
	int wakeme = 0, cont = -1;
	uchar istat, dstat;
	ushort sist;
	Controller *c = a;
	Ncr *n = c->n;
	Dsa *dsa;

	USED(ur);
	if (DEBUG(1))
		IPRINT(PRINTPREFIX "int\n");
	ilock(c);
	istat = n->istat;
	if (istat & Intf) {
		Dsa *d;
		int wokesomething = 0;
		if (DEBUG(1))
			IPRINT(PRINTPREFIX "Intfly\n");
		n->istat = Intf;
		/* search for structures in A_STATE_DONE */
		for (d = KPTR(legetl(c->dsalist.head)); d; d = KPTR(legetl(d->next))) {
			if (d->stateb == A_STATE_DONE) {
				d->p9status = STATUS_COMPLETE | d->status;
				if (DEBUG(1))
					IPRINT(PRINTPREFIX "waking up dsa %lux\n", (ulong)d);
				wakeup(d);
				wokesomething = 1;
			}
		}
		if (!wokesomething)
			IPRINT(PRINTPREFIX "nothing to wake up\n");
	}

	if ((istat & (Sip | Dip)) == 0) {
		if (DEBUG(1))
			IPRINT(PRINTPREFIX "int end %x\n", istat);
		iunlock(c);
		return;
	}

	sist = (n->sist1<<8)|n->sist0;	/* BUG? can two-byte read be inconsistent? */
	dstat = n->dstat;

	dsa = (Dsa *)DMASEG_TO_KADDR(legetl(n->dsa));
	c->running = 0;
	if (dsa == nil || dsa == (Dsa *)-1)
		panic("53c8xx: dsa == %ld in interrupt; bad controller", (long)dsa);
	if (istat & Sip) {
		if (DEBUG(1))
			IPRINT("sist = %.4x\n", sist);
		if (sist & 0x80) {
			ulong addr;
			ulong sa;
			ulong dbc;
			ulong tbc;
			int dmablks;
			ulong dmaaddr;

			addr = legetl(n->dsp);
			sa = addr - c->scriptpa;
			if (DEBUG(1) || DEBUG(2))
				IPRINT(PRINTPREFIX "%d/%d: Phase Mismatch sa=%.8lux\n",
				    dsa->target, dsa->lun, sa);
			/*
			 * now recover
			 */
			if (sa == E_data_in_mismatch) {
				dbc = read_mismatch_recover(c, n, dsa);
				tbc = legetl(dsa->data_buf.dbc) - dbc;
				advancedata(&dsa->data_buf, tbc);
				if (DEBUG(1) || DEBUG(2))
					IPRINT(PRINTPREFIX "%d/%d: transferred = %ld residue = %ld\n",
					    dsa->target, dsa->lun, tbc, legetl(dsa->data_buf.dbc));
				cont = E_to_decisions;
			}
			else if (sa == E_data_in_block_mismatch) {
				dbc = read_mismatch_recover(c, n, dsa);
				tbc = A_BSIZE - dbc;
				/* recover current state from registers */
				dmablks = n->scratcha[2];
				dmaaddr = legetl(n->scratchb);
				/* we have got to dmaaddr + tbc */
				/* we have dmablks * A_BSIZE - tbc + residue left to do */
				/* so remaining transfer is */
				IPRINT("in_block_mismatch: dmaaddr = 0x%lux tbc=%lud dmablks=%d\n",
				    dmaaddr, tbc, dmablks);
				calcblockdma(dsa, dmaaddr + tbc,
				    dmablks * A_BSIZE - tbc + legetl(dsa->data_buf.dbc));
				/* copy changes into scratch registers */
				IPRINT("recalc: dmablks %d dmaaddr 0x%lx pa 0x%lx dbc %ld\n",
				    dsa->dmablks, legetl(dsa->dmaaddr),
				    legetl(dsa->data_buf.pa), legetl(dsa->data_buf.dbc));
				n->scratcha[2] = dsa->dmablks;
				lesetl(n->scratchb, dsa->dmancr);
				cont = E_data_block_mismatch_recover;
			}
			else if (sa == E_data_out_mismatch) {
				dbc = write_mismatch_recover(c, n, dsa);
				tbc = legetl(dsa->data_buf.dbc) - dbc;
				advancedata(&dsa->data_buf, tbc);
				if (DEBUG(1) || DEBUG(2))
					IPRINT(PRINTPREFIX "%d/%d: transferred = %ld residue = %ld\n",
					    dsa->target, dsa->lun, tbc, legetl(dsa->data_buf.dbc));
				cont = E_to_decisions;
			}
			else if (sa == E_data_out_block_mismatch) {
				dbc = write_mismatch_recover(c, n, dsa);
				tbc = legetl(dsa->data_buf.dbc) - dbc;
				/* recover current state from registers */
				dmablks = n->scratcha[2];
				dmaaddr = legetl(n->scratchb);
				/* we have got to dmaaddr + tbc */
				/* we have dmablks blocks - tbc + residue left to do */
				/* so remaining transfer is */
				IPRINT("out_block_mismatch: dmaaddr = %lux tbc=%lud dmablks=%d\n",
				    dmaaddr, tbc, dmablks);
				calcblockdma(dsa, dmaaddr + tbc,
				    dmablks * A_BSIZE - tbc + legetl(dsa->data_buf.dbc));
				/* copy changes into scratch registers */
				n->scratcha[2] = dsa->dmablks;
				lesetl(n->scratchb, dsa->dmancr);
				cont = E_data_block_mismatch_recover;
			}
			else if (sa == E_id_out_mismatch) {
				/*
				 * target switched phases while attention held during
				 * message out. The possibilities are:
				 * 1. It didn't like the last message. This is indicated
				 *    by the new phase being message_in. Use script to recover
				 *
				 * 2. It's not SCSI-II compliant. The new phase will be other
				 *    than message_in. We should also indicate that the device
				 *    is asynchronous, if it's the SDTR that got ignored
				 *
				 * For now, if the phase switch is not to message_in, and
				 * and it happens after IDENTIFY and before SDTR, we
				 * notify the negotiation state machine.
				 */
				ulong lim = legetl(dsa->msg_out_buf.dbc);
				uchar p = n->sstat1 & 7;
				dbc = write_mismatch_recover(c, n, dsa);
				tbc = lim - dbc;
				IPRINT(PRINTPREFIX "%d/%d: msg_out_mismatch: %lud/%lud sent, phase %s\n",
				    dsa->target, dsa->lun, tbc, lim, phase[p]);
				if (p != MessageIn && tbc == 1) {
					msgsm(dsa, c, A_SIR_EV_PHASE_SWITCH_AFTER_ID, &cont, &wakeme);
				}
				else
					cont = E_id_out_mismatch_recover;
			}
			else if (sa == E_cmd_out_mismatch) {
				/*
				 * probably the command count is longer than the device wants ...
				 */
				ulong lim = legetl(dsa->cmd_buf.dbc);
				uchar p = n->sstat1 & 7;
				dbc = write_mismatch_recover(c, n, dsa);
				tbc = lim - dbc;
				IPRINT(PRINTPREFIX "%d/%d: cmd_out_mismatch: %lud/%lud sent, phase %s\n",
				    dsa->target, dsa->lun, tbc, lim, phase[p]);
				USED(p, tbc);
				cont = E_to_decisions;
			}
			else {
				IPRINT(PRINTPREFIX "%d/%d: ma sa=%.8lux wanted=%s got=%s\n",
				    dsa->target, dsa->lun, sa,
				    phase[n->dcmd & 7],
				    phase[n->sstat1 & 7]);
				dumpncrregs(c, 1);
				dsa->p9status = STATUS_FAIL;	/* chf */
				wakeme = 1;
			}
		}
		/*else*/ if (sist & 0x400) {
			if (DEBUG(0))
				IPRINT(PRINTPREFIX "%d/%d Sto\n", dsa->target, dsa->lun);
			dsa->p9status = STATUS_SELECTION_TIMEOUT;
			dsa->stateb = A_STATE_DONE;
			softreset(c);
			cont = E_issue_check;
			wakeme = 1;
		}
		if (sist & 0x1) {
			IPRINT(PRINTPREFIX "%d/%d: parity error\n", dsa->target, dsa->lun);
			dsa->parityerror = 1;
		}
		if (sist & 0x4) {
			IPRINT(PRINTPREFIX "%d/%d: unexpected disconnect\n",
			    dsa->target, dsa->lun);
			dumpncrregs(c, 1);
			//wakeme = 1;
			dsa->p9status = STATUS_FAIL;
		}
	}
	if (istat & Dip) {
		if (DEBUG(1))
			IPRINT("dstat = %.2x\n", dstat);
		/*else*/ if (dstat & Ssi) {
			ulong *p = DMASEG_TO_KADDR(legetl(n->dsp));
			ulong w = (uchar *)p - (uchar *)c->script;
			IPRINT("[%lux]", w);
			USED(w);
			cont = -2;	/* restart */
		}
		if (dstat & Sir) {
			switch (legetl(n->dsps)) {
			case A_SIR_MSG_IO_COMPLETE:
				dsa->p9status = STATUS_COMPLETE | dsa->status;
				wakeme = 1;
				break;
			case A_SIR_MSG_SDTR:
			case A_SIR_MSG_WDTR:
			case A_SIR_MSG_REJECT:
			case A_SIR_EV_RESPONSE_OK:
				msgsm(dsa, c, legetl(n->dsps), &cont, &wakeme);
				break;
			case A_SIR_MSG_IGNORE_WIDE_RESIDUE:
				/* back up one in the data transfer */
				IPRINT(PRINTPREFIX "%d/%d: ignore wide residue %d, WSR = %d\n",
				    dsa->target, dsa->lun, n->scratcha[1], n->scntl2 & 1);
				if (dsa->dmablks == 0 && dsa->flag)
					IPRINT(PRINTPREFIX "%d/%d: transfer over; residue ignored\n",
					    dsa->target, dsa->lun);
				else
					calcblockdma(dsa, legetl(dsa->dmaaddr) - 1,
					    dsa->dmablks * A_BSIZE + legetl(dsa->data_buf.dbc) + 1);
				cont = -2;
				break;
			case A_SIR_ERROR_NOT_MSG_IN_AFTER_RESELECT:
				IPRINT(PRINTPREFIX "%d: not msg_in after reselect (%s)",
				    n->ssid & SSIDMASK(c), phase[n->sstat1 & 7]);
				dsa = dsafind(c, n->ssid & SSIDMASK(c), -1, A_STATE_DISCONNECTED);
				dumpncrregs(c, 1);
				wakeme = 1;
				break;
			case A_SIR_NOTIFY_MSG_IN:
				IPRINT(PRINTPREFIX "%d/%d: msg_in %d\n",
				    dsa->target, dsa->lun, n->sfbr);
				cont = -2;
				break;
			case A_SIR_NOTIFY_DISC:
				IPRINT(PRINTPREFIX "%d/%d: disconnect:", dsa->target, dsa->lun);
				goto dsadump;
			case A_SIR_NOTIFY_STATUS:
				IPRINT(PRINTPREFIX "%d/%d: status\n", dsa->target, dsa->lun);
				cont = -2;
				break;
			case A_SIR_NOTIFY_COMMAND:
				IPRINT(PRINTPREFIX "%d/%d: commands\n", dsa->target, dsa->lun);
				cont = -2;
				break;
			case A_SIR_NOTIFY_DATA_IN:
				IPRINT(PRINTPREFIX "%d/%d: data in a %lx b %lx\n",
				    dsa->target, dsa->lun, legetl(n->scratcha), legetl(n->scratchb));
				cont = -2;
				break;
			case A_SIR_NOTIFY_BLOCK_DATA_IN:
				IPRINT(PRINTPREFIX "%d/%d: block data in: a2 %x b %lx\n",
				    dsa->target, dsa->lun, n->scratcha[2], legetl(n->scratchb));
				cont = -2;
				break;
			case A_SIR_NOTIFY_DATA_OUT:
				IPRINT(PRINTPREFIX "%d/%d: data out\n", dsa->target, dsa->lun);
				cont = -2;
				break;
			case A_SIR_NOTIFY_DUMP:
				IPRINT(PRINTPREFIX "%d/%d: dump\n", dsa->target, dsa->lun);
				dumpncrregs(c, 1);
				cont = -2;
				break;
			case A_SIR_NOTIFY_DUMP2:
				IPRINT(PRINTPREFIX "%d/%d: dump2:", dsa->target, dsa->lun);
				IPRINT(" sa %lux", legetl(n->dsp) - c->scriptpa);
				IPRINT(" dsa %lux", legetl(n->dsa));
				IPRINT(" sfbr %ux", n->sfbr);
				IPRINT(" a %lux", legetl(n->scratcha));
				IPRINT(" b %lux", legetl(n->scratchb));
				IPRINT(" ssid %ux", n->ssid);
				IPRINT("\n");
				cont = -2;
				break;
			case A_SIR_NOTIFY_WAIT_RESELECT:
				IPRINT(PRINTPREFIX "wait reselect\n");
				cont = -2;
				break;
			case A_SIR_NOTIFY_RESELECT:
				IPRINT(PRINTPREFIX "reselect: ssid %.2x sfbr %.2x at %ld\n",
				    n->ssid, n->sfbr, TK2MS(m->ticks));
				cont = -2;
				break;
			case A_SIR_NOTIFY_ISSUE:
				IPRINT(PRINTPREFIX "%d/%d: issue:", dsa->target, dsa->lun);
			dsadump:
				IPRINT(" tgt=%d", dsa->target);
				IPRINT(" time=%ld", TK2MS(m->ticks));
				IPRINT("\n");
				cont = -2;
				break;
			case A_SIR_NOTIFY_ISSUE_CHECK:
				IPRINT(PRINTPREFIX "issue check\n");
				cont = -2;
				break;
			case A_SIR_NOTIFY_SIGP:
				IPRINT(PRINTPREFIX "responded to SIGP\n");
				cont = -2;
				break;
			case A_SIR_NOTIFY_DUMP_NEXT_CODE: {
				ulong *dsp = DMASEG_TO_KADDR(legetl(n->dsp));
				int x;
				IPRINT(PRINTPREFIX "code at %lux", dsp - c->script);
				for (x = 0; x < 6; x++)
					IPRINT(" %.8lux", dsp[x]);
				IPRINT("\n");
				USED(dsp);
				cont = -2;
				break;
			}
			case A_SIR_NOTIFY_WSR:
				IPRINT(PRINTPREFIX "%d/%d: WSR set\n", dsa->target, dsa->lun);
				cont = -2;
				break;
			case A_SIR_NOTIFY_LOAD_SYNC:
				IPRINT(PRINTPREFIX "%d/%d: scntl=%.2x sxfer=%.2x\n",
				    dsa->target, dsa->lun, n->scntl3, n->sxfer);
				cont = -2;
				break;
			case A_SIR_NOTIFY_RESELECTED_ON_SELECT:
				IPRINT(PRINTPREFIX "%d/%d: reselected during select\n",
				    dsa->target, dsa->lun);
				cont = -2;
				break;
			default:
				IPRINT(PRINTPREFIX "%d/%d: script error %ld\n",
					dsa->target, dsa->lun, legetl(n->dsps));
				dumpncrregs(c, 1);
				wakeme = 1;
			}
		}
		/*else*/ if (dstat & Iid) {
			ulong addr = legetl(n->dsp);
			ulong dbc = (n->dbc[2]<<16)|(n->dbc[1]<<8)|n->dbc[0];
			IPRINT(PRINTPREFIX "%d/%d: Iid pa=%.8lux sa=%.8lux dbc=%lux\n",
			    dsa->target, dsa->lun,
			    addr, addr - c->scriptpa, dbc);
			addr = (ulong)DMASEG_TO_KADDR(addr);
			IPRINT("%.8lux %.8lux %.8lux\n",
			    *(ulong *)(addr - 12), *(ulong *)(addr - 8), *(ulong *)(addr - 4));
			USED(addr, dbc);
			if (dsa)
				dsa->p9status = STATUS_FAIL;
			wakeme = 1;
		}
		/*else*/ if (dstat & Bf) {
			if (dsa == nil)
				print(PRINTPREFIX "Bus Fault with dsa==0\n");
			else {
				print(PRINTPREFIX "%d/%d: Bus Fault\n", dsa->target, dsa->lun);
				dsa->p9status = STATUS_FAIL;
			}
			dumpncrregs(c, 1);
			wakeme = 1;
		}
	}
	if (cont == -2)
		ncrcontinue(c);
	else if (cont >= 0)
		start(c, cont);
	if (wakeme && dsa){
		if(dsa->p9status == 0xffff)
			dsa->p9status = STATUS_FAIL;
		wakeup(dsa);
	}
	iunlock(c);
	if (DEBUG(1)) {
		IPRINT(PRINTPREFIX "int end 1\n");
	}
}

static int
done(void *arg)
{
	return ((Dsa *)arg)->p9status != 0xffff;
}

static int
xfunc(Controller *c, enum na_external x, unsigned long *v)
{
	switch (x) {
	default:
		print("xfunc: can't find external %d\n", x);
		return 0;
	case X_scsi_id_buf:
		*v = offsetof(Dsa, scsi_id_buf[0]);
		break;
	case X_msg_out_buf:
		*v = offsetof(Dsa, msg_out_buf);
		break;
	case X_cmd_buf:
		*v = offsetof(Dsa, cmd_buf);
		break;
	case X_data_buf:
		*v = offsetof(Dsa, data_buf);
		break;
	case X_status_buf:
		*v = offsetof(Dsa, status_buf);
		break;
	case X_dsa_head:
		*v = DMASEG(&c->dsalist.head[0]);
		break;
	case X_ssid_mask:
		*v = SSIDMASK(c);
		break;
	}
	return 1;
}

static void
setmovedata(Movedata *d, ulong pa, ulong bc)
{
	d->pa[0] = pa;
	d->pa[1] = pa>>8;
	d->pa[2] = pa>>16;
	d->pa[3] = pa>>24;
	d->dbc[0] = bc;
	d->dbc[1] = bc>>8;
	d->dbc[2] = bc>>16;
	d->dbc[3] = bc>>24;
}

static void
advancedata(Movedata *d, long v)
{
	lesetl(d->pa, legetl(d->pa) + v);
	lesetl(d->dbc, legetl(d->dbc) - v);
}

static void
dumpwritedata(uchar *data, int datalen)
{
	int i;
	uchar *bp;
	if (!DEBUG(0)){
		USED(data, datalen);
		return;
	}

	if (datalen) {
		KPRINT(PRINTPREFIX "write:");
		for (i = 0, bp = data; i < 50 && i < datalen; i++, bp++)
			KPRINT("%.2ux", *bp);
		if (i < datalen) {
			KPRINT("...");
		}
		KPRINT("\n");
	}
}

static void
dumpreaddata(uchar *data, int datalen)
{
	int i;
	uchar *bp;
	if (!DEBUG(0)){
		USED(data, datalen);
		return;
	}

	if (datalen) {
		KPRINT(PRINTPREFIX "read:");
		for (i = 0, bp = data; i < 50 && i < datalen; i++, bp++)
			KPRINT("%.2ux", *bp);
		if (i < datalen) {
			KPRINT("...");
		}
		KPRINT("\n");
	}
}

static void
busreset(Controller *c)
{
	int x, ntarget;

	/* bus reset */
	c->n->scntl1 |= (1 << 3);
	delay(500);
	c->n->scntl1 &= ~(1 << 3);
	if(!(c->v->feature & Wide))
		ntarget = 8;
	else
		ntarget = MAXTARGET;
	for (x = 0; x < ntarget; x++) {
		setwide(0, c, x, 0);
#ifndef ASYNC_ONLY
		c->s[x] = NeitherDone;
#endif
	}
	c->capvalid = 0;
}

static void
reset(Controller *c)
{
	/* should wakeup all pending tasks */
	softreset(c);
	busreset(c);
}

static int
io(Controller *c, uchar target, uchar lun, int rw, uchar *cmd, int cmdlen, uchar *data, int datalen,