uda.c

早期freebsd实现

 * This routine is broken into two so that the internal version
 * udastrat1() can be called by the (nonexistent, as yet) bad block
 * revectoring routine.
 */
udastrategy(bp)
	register struct buf *bp;
{
	register int unit;
	register struct uba_device *ui;
	register struct ra_info *ra;
	struct partition *pp;
	int p;
	daddr_t sz, maxsz;

	/*
	 * Make sure this is a reasonable drive to use.
	 */
	if ((unit = udaunit(bp->b_dev)) >= NRA ||
	    (ui = udadinfo[unit]) == NULL || ui->ui_alive == 0 ||
	    (ra = &ra_info[unit])->ra_state == CLOSED) {
		bp->b_error = ENXIO;
		goto bad;
	}

	/*
	 * If drive is open `raw' or reading label, let it at it.
	 */
	if (ra->ra_state < OPEN) {
		udastrat1(bp);
		return;
	}
	p = udapart(bp->b_dev);
	if ((ra->ra_openpart & (1 << p)) == 0) {
		bp->b_error = ENODEV;
		goto bad;
	}

	/*
	 * Determine the size of the transfer, and make sure it is
	 * within the boundaries of the partition.
	 */
	pp = &udalabel[unit].d_partitions[p];
	maxsz = pp->p_size;
	if (pp->p_offset + pp->p_size > ra->ra_dsize)
		maxsz = ra->ra_dsize - pp->p_offset;
	sz = (bp->b_bcount + DEV_BSIZE - 1) >> DEV_BSHIFT;
	if (bp->b_blkno + pp->p_offset <= LABELSECTOR &&
#if LABELSECTOR != 0
	    bp->b_blkno + pp->p_offset + sz > LABELSECTOR &&
#endif
	    (bp->b_flags & B_READ) == 0 && ra->ra_wlabel == 0) {
		bp->b_error = EROFS;
		goto bad;
	}
	if (bp->b_blkno < 0 || bp->b_blkno + sz > maxsz) {
		/* if exactly at end of disk, return an EOF */
		if (bp->b_blkno == maxsz) {
			bp->b_resid = bp->b_bcount;
			biodone(bp);
			return;
		}
		/* or truncate if part of it fits */
		sz = maxsz - bp->b_blkno;
		if (sz <= 0) {
			bp->b_error = EINVAL;	/* or hang it up */
			goto bad;
		}
		bp->b_bcount = sz << DEV_BSHIFT;
	}
	udastrat1(bp);
	return;
bad:
	bp->b_flags |= B_ERROR;
	biodone(bp);
}

/*
 * Work routine for udastrategy.
 */
udastrat1(bp)
	register struct buf *bp;
{
	register int unit = udaunit(bp->b_dev);
	register struct uba_ctlr *um;
	register struct buf *dp;
	struct uba_device *ui;
	int s = spl5();

	/*
	 * Append the buffer to the drive queue, and if it is not
	 * already there, the drive to the controller queue.  (However,
	 * if the drive queue is marked to be requeued, we must be
	 * awaiting an on line or get unit status command; in this
	 * case, leave it off the controller queue.)
	 */
	um = (ui = udadinfo[unit])->ui_mi;
	dp = &udautab[unit];
	APPEND(bp, dp, av_forw);
	if (dp->b_active == 0 && (ui->ui_flags & UNIT_REQUEUE) == 0) {
		APPEND(dp, &um->um_tab, b_forw);
		dp->b_active++;
	}

	/*
	 * Start activity on the controller.  Note that unlike other
	 * Unibus drivers, we must always do this, not just when the
	 * controller is not active.
	 */
	udastart(um);
	splx(s);
}

/*
 * Start up whatever transfers we can find.
 * Note that udastart() must be called at spl5().
 */
udastart(um)
	register struct uba_ctlr *um;
{
	register struct uda_softc *sc = &uda_softc[um->um_ctlr];
	register struct buf *bp, *dp;
	register struct mscp *mp;
	struct uba_device *ui;
	struct udadevice *udaddr;
	struct partition *pp;
	int i, sz;

#ifdef lint
	i = 0; i = i;
#endif
	/*
	 * If it is not running, try (again and again...) to initialise
	 * it.  If it is currently initialising just ignore it for now.
	 */
	if (sc->sc_state != ST_RUN) {
		if (sc->sc_state == ST_IDLE && udainit(um->um_ctlr))
			printf("uda%d: still hung\n", um->um_ctlr);
		return;
	}

	/*
	 * If um_cmd is nonzero, this controller is on the Unibus
	 * resource wait queue.  It will not help to try more requests;
	 * instead, when the Unibus unblocks and calls udadgo(), we
	 * will call udastart() again.
	 */
	if (um->um_cmd)
		return;

	sc->sc_flags |= SC_INSTART;
	udaddr = (struct udadevice *) um->um_addr;

loop:
	/*
	 * Service the drive at the head of the queue.  It may not
	 * need anything, in which case it might be shutting down
	 * in udaclose().
	 */
	if ((dp = um->um_tab.b_actf) == NULL)
		goto out;
	if ((bp = dp->b_actf) == NULL) {
		dp->b_active = 0;
		um->um_tab.b_actf = dp->b_forw;
		if (ra_info[dp - udautab].ra_openpart == 0)
			wakeup((caddr_t)dp); /* finish close protocol */
		goto loop;
	}

	if (udaddr->udasa & UDA_ERR) {	/* ctlr fatal error */
		udasaerror(um, 1);
		goto out;
	}

	/*
	 * Get an MSCP packet, then figure out what to do.  If
	 * we cannot get a command packet, the command ring may
	 * be too small:  We should have at least as many command
	 * packets as credits, for best performance.
	 */
	if ((mp = mscp_getcp(&sc->sc_mi, MSCP_DONTWAIT)) == NULL) {
		if (sc->sc_mi.mi_credits > MSCP_MINCREDITS &&
		    (sc->sc_flags & SC_GRIPED) == 0) {
			log(LOG_NOTICE, "uda%d: command ring too small\n",
				um->um_ctlr);
			sc->sc_flags |= SC_GRIPED;/* complain only once */
		}
		goto out;
	}

	/*
	 * Bring the drive on line if it is not already.  Get its status
	 * if we do not already have it.  Otherwise just start the transfer.
	 */
	ui = udadinfo[udaunit(bp->b_dev)];
	if ((ui->ui_flags & UNIT_ONLINE) == 0) {
		mp->mscp_opcode = M_OP_ONLINE;
		goto common;
	}
	if ((ui->ui_flags & UNIT_HAVESTATUS) == 0) {
		mp->mscp_opcode = M_OP_GETUNITST;
common:
if (ui->ui_flags & UNIT_REQUEUE) panic("udastart");
		/*
		 * Take the drive off the controller queue.  When the
		 * command finishes, make sure the drive is requeued.
		 */
		um->um_tab.b_actf = dp->b_forw;
		dp->b_active = 0;
		ui->ui_flags |= UNIT_REQUEUE;
		mp->mscp_unit = ui->ui_slave;
		*mp->mscp_addr |= MSCP_OWN | MSCP_INT;
		sc->sc_flags |= SC_STARTPOLL;
#ifdef POLLSTATS
		sc->sc_ncmd++;
#endif
		goto loop;
	}

	pp = &udalabel[ui->ui_unit].d_partitions[udapart(bp->b_dev)];
	mp->mscp_opcode = (bp->b_flags & B_READ) ? M_OP_READ : M_OP_WRITE;
	mp->mscp_unit = ui->ui_slave;
	mp->mscp_seq.seq_lbn = bp->b_blkno + pp->p_offset;
	sz = (bp->b_bcount + DEV_BSIZE - 1) >> DEV_BSHIFT;
	mp->mscp_seq.seq_bytecount = bp->b_blkno + sz > pp->p_size ?
		(pp->p_size - bp->b_blkno) >> DEV_BSHIFT : bp->b_bcount;
	/* mscp_cmdref is filled in by mscp_go() */

	/*
	 * Drop the packet pointer into the `command' field so udadgo()
	 * can tell what to start.  If ubago returns 1, we can do another
	 * transfer.  If not, um_cmd will still point at mp, so we will
	 * know that we are waiting for resources.
	 */
	um->um_cmd = (int)mp;
	if (ubago(ui))
		goto loop;

	/*
	 * All done, or blocked in ubago().  If we managed to
	 * issue some commands, start up the beast.
	 */
out:
	if (sc->sc_flags & SC_STARTPOLL) {
#ifdef POLLSTATS
		udastats.cmd[sc->sc_ncmd]++;
		sc->sc_ncmd = 0;
#endif
		i = ((struct udadevice *)um->um_addr)->udaip;
	}
	sc->sc_flags &= ~(SC_INSTART | SC_STARTPOLL);
}

/*
 * Start a transfer.
 *
 * If we are not called from within udastart(), we must have been
 * blocked, so call udastart to do more requests (if any).  If
 * this calls us again immediately we will not recurse, because
 * that time we will be in udastart().  Clever....
 */
udadgo(um)
	register struct uba_ctlr *um;
{
	struct uda_softc *sc = &uda_softc[um->um_ctlr];
	struct mscp *mp = (struct mscp *)um->um_cmd;

	um->um_tab.b_active++;	/* another transfer going */

	/*
	 * Fill in the MSCP packet and move the buffer to the
	 * I/O wait queue.  Mark the controller as no longer on
	 * the resource queue, and remember to initiate polling.
	 */
	mp->mscp_seq.seq_buffer = UBAI_ADDR(um->um_ubinfo) |
		(UBAI_BDP(um->um_ubinfo) << 24);
	mscp_go(&sc->sc_mi, mp, um->um_ubinfo);
	um->um_cmd = 0;	
	um->um_ubinfo = 0;	/* tyke it awye */
	sc->sc_flags |= SC_STARTPOLL;
#ifdef POLLSTATS
	sc->sc_ncmd++;
#endif
	if ((sc->sc_flags & SC_INSTART) == 0)
		udastart(um);
}

udaiodone(mi, bp, info)
	register struct mscp_info *mi;
	struct buf *bp;
	int info;
{
	register struct uba_ctlr *um = udaminfo[mi->mi_ctlr];

	um->um_ubinfo = info;
	ubadone(um);
	biodone(bp);
	if (um->um_bdp && mi->mi_wtab.av_forw == &mi->mi_wtab)
		ubarelse(um->um_ubanum, &um->um_bdp);
	um->um_tab.b_active--;	/* another transfer done */
}

static struct saerr {
	int	code;		/* error code (including UDA_ERR) */
	char	*desc;		/* what it means: Efoo => foo error */
} saerr[] = {
	{ 0100001, "Eunibus packet read" },
	{ 0100002, "Eunibus packet write" },
	{ 0100003, "EUDA ROM and RAM parity" },
	{ 0100004, "EUDA RAM parity" },
	{ 0100005, "EUDA ROM parity" },
	{ 0100006, "Eunibus ring read" },
	{ 0100007, "Eunibus ring write" },
	{ 0100010, " unibus interrupt master failure" },
	{ 0100011, "Ehost access timeout" },
	{ 0100012, " host exceeded command limit" },
	{ 0100013, " unibus bus master failure" },
	{ 0100014, " DM XFC fatal error" },
	{ 0100015, " hardware timeout of instruction loop" },
	{ 0100016, " invalid virtual circuit id" },
	{ 0100017, "Eunibus interrupt write" },
	{ 0104000, "Efatal sequence" },
	{ 0104040, " D proc ALU" },
	{ 0104041, "ED proc control ROM parity" },
	{ 0105102, "ED proc w/no BD#2 or RAM parity" },
	{ 0105105, "ED proc RAM buffer" },
	{ 0105152, "ED proc SDI" },
	{ 0105153, "ED proc write mode wrap serdes" },
	{ 0105154, "ED proc read mode serdes, RSGEN & ECC" },
	{ 0106040, "EU proc ALU" },
	{ 0106041, "EU proc control reg" },
	{ 0106042, " U proc DFAIL/cntl ROM parity/BD #1 test CNT" },
	{ 0106047, " U proc const PROM err w/D proc running SDI test" },
	{ 0106055, " unexpected trap" },
	{ 0106071, "EU proc const PROM" },
	{ 0106072, "EU proc control ROM parity" },
	{ 0106200, "Estep 1 data" },
	{ 0107103, "EU proc RAM parity" },
	{ 0107107, "EU proc RAM buffer" },
	{ 0107115, " test count wrong (BD 12)" },
	{ 0112300, "Estep 2" },
	{ 0122240, "ENPR" },
	{ 0122300, "Estep 3" },
	{ 0142300, "Estep 4" },
	{ 0, " unknown error code" }
};

/*
 * If the error bit was set in the controller status register, gripe,
 * then (optionally) reset the controller and requeue pending transfers.
 */
udasaerror(um, doreset)
	register struct uba_ctlr *um;
	int doreset;
{
	register int code = ((struct udadevice *)um->um_addr)->udasa;
	register struct saerr *e;

	if ((code & UDA_ERR) == 0)
		return;
	for (e = saerr; e->code; e++)
		if (e->code == code)
			break;
	printf("uda%d: controller error, sa=0%o (%s%s)\n",
		um->um_ctlr, code, e->desc + 1,
		*e->desc == 'E' ? " error" : "");
	if (doreset) {
		mscp_requeue(&uda_softc[um->um_ctlr].sc_mi);
		(void) udainit(um->um_ctlr);
	}
}

/*
 * Interrupt routine.  Depending on the state of the controller,
 * continue initialisation, or acknowledge command and response
 * interrupts, and process responses.
 */
udaintr(ctlr)
	int ctlr;
{
	register struct uba_ctlr *um = udaminfo[ctlr];
	register struct uda_softc *sc = &uda_softc[ctlr];
	register struct udadevice *udaddr = (struct udadevice *)um->um_addr;
	register struct uda *ud;
	register struct mscp *mp;
	register int i;

#ifdef QBA
	splx(sc->sc_ipl);	/* Qbus interrupt protocol is odd */
#endif
	sc->sc_wticks = 0;	/* reset interrupt watchdog */

	/*
	 * Combinations during steps 1, 2, and 3: STEPnMASK
	 * corresponds to which bits should be tested;
	 * STEPnGOOD corresponds to the pattern that should
	 * appear after the interrupt from STEPn initialisation.
	 * All steps test the bits in ALLSTEPS.
	 */
#define	ALLSTEPS	(UDA_ERR|UDA_STEP4|UDA_STEP3|UDA_STEP2|UDA_STEP1)

#define	STEP1MASK	(ALLSTEPS | UDA_IE | UDA_NCNRMASK)
#define	STEP1GOOD	(UDA_STEP2 | UDA_IE | (NCMDL2 << 3) | NRSPL2)

#define	STEP2MASK	(ALLSTEPS | UDA_IE | UDA_IVECMASK)
#define	STEP2GOOD	(UDA_STEP3 | UDA_IE | (sc->sc_ivec >> 2))

#define	STEP3MASK	ALLSTEPS
#define	STEP3GOOD	UDA_STEP4

	switch (sc->sc_state) {

	case ST_IDLE:
		/*
		 * Ignore unsolicited interrupts.
		 */
		log(LOG_WARNING, "uda%d: stray intr\n", ctlr);
		return;

	case ST_STEP1:
		/*
		 * Begin step two initialisation.
		 */
		if ((udaddr->udasa & STEP1MASK) != STEP1GOOD) {
			i = 1;
initfailed:
			printf("uda%d: init step %d failed, sa=%b\n",
				ctlr, i, udaddr->udasa, udasr_bits);
			udasaerror(um, 0);
			sc->sc_state = ST_IDLE;
			if (sc->sc_flags & SC_DOWAKE) {
				sc->sc_flags &= ~SC_DOWAKE;
				wakeup((caddr_t)sc);
			}
			return;
		}
		udaddr->udasa = (int)&sc->sc_uda->uda_ca.ca_rspdsc[0] |
			(cpu == VAX_780 || cpu == VAX_8600 ? UDA_PI : 0);
		sc->sc_state = ST_STEP2;
		return;

	case ST_STEP2:
		/*
		 * Begin step 3 initialisation.
		 */
		if ((udaddr->udasa & STEP2MASK) != STEP2GOOD) {
			i = 2;
			goto initfailed;
		}
		udaddr->udasa = ((int)&sc->sc_uda->uda_ca.ca_rspdsc[0]) >> 16;
		sc->sc_state = ST_STEP3;
		return;

	case ST_STEP3:
		/*
		 * Set controller characteristics (finish initialisation).
		 */
		if ((udaddr->udasa & STEP3MASK) != STEP3GOOD) {
			i = 3;
			goto initfailed;
		}
		i = udaddr->udasa & 0xff;
		if (i != sc->sc_micro) {