sdmv50xx.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

		return 0;
	drive = &ctlr->drive[unit->subno];

	e = p+l;
	op = p;
	if(drive->state == Dready){
		p = seprint(p, e, "model    %s\n", drive->model);
		p = seprint(p, e, "serial   %s\n", drive->serial);
		p = seprint(p, e, "firmware %s\n", drive->firmware);
	}else
		p = seprint(p, e, "no disk present\n");
	p = seprint(p, e, "geometry %llud 512\n", drive->sectors);
	p = rdinfo(p, e, drive->info);

	p = rdregs(p, e, drive->chip->arb, regsarb, nelem(regsarb), nil);
	p = rdregs(p, e, drive->bridge, regsbridge, nelem(regsbridge), nil);
	p = rdregs(p, e, drive->edma, regsedma, nelem(regsedma), nil);

	return p-op;
}

static int
mv50wctl(SDunit *unit, Cmdbuf *cb)
{
	Ctlr *ctlr;
	Drive *drive;

	USED(unit);
	if(strcmp(cb->f[0], "reset") == 0){
		ctlr = unit->dev->ctlr;
		drive = &ctlr->drive[unit->subno];
		ilock(drive);
		updatedrive(drive, eDevDis);
		iunlock(drive);
		return 0;
	}
	cmderror(cb, Ebadctl);
	return -1;
}

static char*
mv50rtopctl(SDev *sdev, char *p, char *e)
{
	char name[10];
	Ctlr *ctlr;

	ctlr = sdev->ctlr;
	if(ctlr == nil)
		return p;

	snprint(name, sizeof name, "sd%c", sdev->idno);
	p = rdregs(p, e, ctlr->mmio, regsctlr, nelem(regsctlr), name);
	/* info for first disk */
	p = rdregs(p, e, ctlr->chip[0].arb, regsarb, nelem(regsarb), name);
	p = rdregs(p, e, &ctlr->chip[0].arb->bridge[0], regsbridge, nelem(regsbridge), name);
	p = rdregs(p, e, &ctlr->chip[0].edma[0], regsedma, nelem(regsedma), name);

	return p;
}
#endif

static int
mv50rio(SDreq *r)
{
	int count, max, n, status;
	uchar *cmd, *data;
	uvlong lba;
	Ctlr *ctlr;
	Drive *drive;
	SDunit *unit;
	Srb *srb;

	unit = r->unit;
	ctlr = unit->dev->ctlr;
	drive = &ctlr->drive[unit->subno];
	cmd = r->cmd;

	if((status = sdfakescsi(r, drive->info, sizeof drive->info)) != SDnostatus){
		/* XXX check for SDcheck here */
		r->status = status;
		return status;
	}

	switch(cmd[0]){
	case 0x28:	/* read */
	case 0x2A:	/* write */
		break;
	default:
		print("sdmv50xx: bad cmd 0x%.2ux\n", cmd[0]);
		r->status = SDcheck;
		return SDcheck;
	}

	lba = (cmd[2]<<24)|(cmd[3]<<16)|(cmd[4]<<8)|cmd[5];
	count = (cmd[7]<<8)|cmd[8];
	if(r->data == nil)
		return SDok;
	if(r->dlen < count*unit->secsize)
		count = r->dlen/unit->secsize;

	/*
	 * Could arrange here to have an Srb always outstanding:
	 *
	 *	lsrb = nil;
	 *	while(count > 0 || lsrb != nil){
	 *		srb = nil;
	 *		if(count > 0){
	 *			srb = issue next srb;
	 *		}
	 *		if(lsrb){
	 *			sleep on lsrb and handle it
	 *		}
	 *	}
	 *
	 * On the disks I tried, this didn't help.  If anything,
	 * it's a little slower.		-rsc
	 */
	data = r->data;
	while(count > 0){
		/*
		 * Max is 128 sectors (64kB) because prd->count is 16 bits.
		 */
		max = 128;
		n = count;
		if(n > max)
			n = max;
		srb = srbrw(cmd[0]==0x28 ? SRBread : SRBwrite, drive, data, n, lba);
		ilock(drive);
		startsrb(drive, srb);
		iunlock(drive);

		/*
		 * Cannot let user interrupt the DMA.
		 */
		while(waserror())
			;
		tsleep(srb, srbdone, srb, 60*1000);
		poperror();

		if(!(srb->flag & SFdone)){
			ilock(drive);
			if(!(srb->flag & SFdone)){
				/*
				 * DMA didn't finish but we have to let go of
				 * the data buffer.  Reset the drive to (try to) keep it
				 * from using the buffer after we're gone.
				 */
				iprint("%s: i/o timeout\n", unit->name);
				updatedrive(drive, eDevDis);
				enabledrive(drive);
				freesrb(srb);
				iunlock(drive);
				error("i/o timeout");
			}
			iunlock(drive);
		}

		if(srb->flag & SFerror){
			freesrb(srb);
			error("i/o error");
		}
		freesrb(srb);
		count -= n;
		lba += n;
		data += n*unit->secsize;
	}
	r->rlen = data - (uchar*)r->data;
	return SDok;
err:
	return SDeio;
}

SDifc sdmv50xxifc = {
	"mv50xx",				/* name */

	mv50pnp,			/* pnp */
	nil,				/* legacy */
#ifdef FS
	nil,			/* id */
#endif
	mv50enable,		/* enable */
	mv50disable,		/* disable */

	mv50verify,			/* verify */
	mv50online,			/* online */
	mv50rio,				/* rio */
#ifdef FS
	nil,
	nil,
#else
	mv50rctl,			/* rctl */
	mv50wctl,			/* wctl */
#endif
	scsibio,			/* bio */
#ifndef FS
	nil,			/* probe */
	mv50clear,			/* clear */
	mv50rtopctl,			/* rtopctl */
#endif
};

/*
 * file-server-specific routines
 *
 * mvide* routines implement the `m' device and call the mvsata* routines.
 */

static Drive*
mvsatapart(Drive *dp)
{
	return dp;
}

static Drive*
mvsatadriveprobe(int driveno)
{
	Drive *drive;

	drive = mvsatadrive[driveno];
	if (drive == nil)
		return nil;
	if (drive->magic != Drvmagic)
		print("mv50xx: mvsatadriveprobe(m%d): bad drive magic 0x%lux\n",
			driveno, drive->magic);
	drive->driveno = driveno;
	if(drive->online == 0){
		/* LBA assumed */
		print("m%d: LBA %,llud sectors\n",
			drive->driveno, (Wideoff)drive->sectors);
		drive->online = 1;
	}
	return mvsatapart(drive);
}

/* find all the controllers, enable interrupts, set up SDevs & SDunits */
int
mvsatainit(void)
{
	unsigned i;
	SDev *sdp;
	SDev **sdpp;
	SDunit *sup;
	SDunit **supp;
	static int first = 1;

	if (first)
		first = 0;
	else
		return 0xFF;

	mv50pnp();

	for (sdpp = sdevs; sdpp < sdevs + nelem(sdevs); sdpp++) {
		sdp = *sdpp;
		if (sdp == nil)
			continue;
		i = sdpp - sdevs;
		sdp->ifc = &sdmv50xxifc;
		sdp->nunit = NCtlrdrv;
		sdp->index = i;
		sdp->idno = 'E' + i;
		sdp->ctlr = mvsatactlr[i];
		if (sdp->ctlr != nil)
			mv50enable(sdp);
	}
	for (supp = sdunits; supp < sdunits + nelem(sdunits); supp++) {
		sup = *supp;
		if (sup == nil)
			continue;
		i = supp - sdunits;
		sup->dev = sdevs[i/NCtlrdrv];	/* controller */
		sup->subno = i%NCtlrdrv;	/* drive within controller */
		snprint(sup->name, sizeof sup->name, "m%d", i);
	}
	statsinit();
	return 0xFF;
}

Devsize
mvsataseek(int driveno, Devsize offset)
{
	Drive *drive = mvsatadrive[driveno];

	if (drive == nil || !drive->online)
		return -1;
	drive->offset = offset;
	return offset;
}

/* zero indicates failure; only otherinit() cares */
int
setmv50part(int driveno, char *)
{
	/* mvsatadriveprobe() sets drive->online */
	if(mvsatadriveprobe(driveno) == nil)
		return 0;
	return 1;
}

static void
keepstats(SDunit *unit, int dbytes)
{
	Ctlr *ctlr = unit->dev->ctlr;
	Target *tp = &ctlr->target[unit->subno];

	qlock(tp);
	if(tp->fflag == 0) {
		dofilter(tp->work+0, C0a, C0b, 1);	/* was , 1000); */
		dofilter(tp->work+1, C1a, C1b, 1);	/* was , 1000); */
		dofilter(tp->work+2, C2a, C2b, 1);	/* was , 1000); */
		dofilter(tp->rate+0, C0a, C0b, 1);
		dofilter(tp->rate+1, C1a, C1b, 1);
		dofilter(tp->rate+2, C2a, C2b, 1);
		tp->fflag = 1;
	}
	tp->work[0].count++;
	tp->work[1].count++;
	tp->work[2].count++;
	tp->rate[0].count += dbytes;
	tp->rate[1].count += dbytes;
	tp->rate[2].count += dbytes;
	qunlock(tp);
}

static long
mvsataxfer(Drive *dp, void *, int inout, Devsize start, long bytes)
{
	unsigned driveno = dp->driveno;
	ulong secsize = dp->unit->secsize, sects;
	SDunit *unit;
	SDunit **unitp = sdunits + driveno;
	static int beenhere;

	DPRINT("%s: mvsataxfer\n", dp->unit->name);
	unit = *unitp;
	if (unit == nil) {
		print("mvsataxfer: nil unit\n");
		return -1;
	}
	if (!beenhere && dp->unit != unit) {
		beenhere = 1;
		print("mvsataxfer: units differ: dp->unit %p unit %p\n",
			dp->unit, unit);
	}
	if (dp->driveno == -1)
		panic("mvsataxfer: dp->driveno unset");
	if (unit->dev != sdevs[driveno/NCtlrdrv])
		panic("mvsataxfer: SDunit[%d].dev is wrong controller", driveno);
	if (unit->subno != driveno%NCtlrdrv)
		panic("mvsataxfer: SDunit[%d].subno is %d, not %d",
			driveno, unit->subno, driveno%NCtlrdrv);
	if (unit->sectors == 0) {
		unit->sectors = dp->sectors;
		unit->secsize = secsize;
	}
	keepstats(unit, bytes);
	sects = (bytes + secsize - 1) / secsize;	/* round up */
	if (start%secsize != 0)
		print("mvsataxfer: start offset not on sector boundary\n");
	return scsibio(unit, 0, inout, dp->buf, sects, start/secsize);
}

/*
 * mvsataread & mvsatawrite do the real work;
 * mvideread & mvidewrite just call them.
 * mvsataread & mvsatawrite are called by the nvram routines.
 * mvideread & mvidewrite are called for normal file server I/O.
 */

Off
mvsataread(int driveno, void *a, long n)
{
	int skip;
	Off rv, i;
	uchar *aa = a;
//	Ctlr *cp;
	Drive *dp;

	DPRINT("m%d: mvsataread\n", driveno);
	dp = mvsatadrive[driveno];
	if(dp == nil || !dp->online)
		return 0;
	DPRINT("%s: mvsataread drive=%p\n", dp->unit->name, dp);

//	cp = dp->ctlr;
	if (dp->unit->secsize == 0)
		panic("mvsataread: %s: sector size of zero", dp->unit->name);
	skip = dp->offset % dp->unit->secsize;
	for(rv = 0; rv < n; rv += i){
		i = mvsataxfer(dp, nil, Read, dp->offset+rv-skip, n-rv+skip);
		if(i == 0)
			break;
		if(i < 0) {
			return -1;
		}
		i -= skip;
		if(i > n - rv)
			i = n - rv;
		memmove(aa+rv, dp->buf + skip, i);
		skip = 0;
	}
	dp->offset += rv;
	return rv;
}

Off
mvsatawrite(int driveno, void *a, long n)
{
	Off rv, i, partial;
	uchar *aa = a;
//	Ctlr *cp;
	Drive *dp;

	DPRINT("m%d: mvsatawrite\n", driveno);
	dp = mvsatadrive[driveno];
	if(dp == nil || !dp->online)
		return 0;
	DPRINT("%s: mvsatawrite drive=%p\n", dp->unit->name, dp);

//	cp = dp->ctlr;

	/*
	 *  if not starting on a sector boundary,
	 *  read in the first sector before writing it out.
	 */
	if (dp->unit->secsize == 0)
		panic("mvsatawrite: %s: sector size of zero", dp->unit->name);
	partial = dp->offset % dp->unit->secsize;
	if(partial){
		if (mvsataxfer(dp, nil, Read, dp->offset-partial,
		    dp->unit->secsize) < 0)
			return -1;
		if(partial+n > dp->unit->secsize)
			rv = dp->unit->secsize - partial;
		else
			rv = n;
		memmove(dp->buf+partial, aa, rv);
		if (mvsataxfer(dp, nil, Write, dp->offset-partial,
		    dp->unit->secsize) < 0)
			return -1;
	} else
		rv = 0;

	/*
	 *  write out the full sectors (common case)
	 */
	partial = (n - rv) % dp->unit->secsize;
	n -= partial;
	for(; rv < n; rv += i){
		i = n - rv;
		if(i > Maxxfer)
			i = Maxxfer;
		memmove(dp->buf, aa+rv, i);
		i = mvsataxfer(dp, nil, Write, dp->offset+rv, i);
		if(i == 0)
			break;
		if(i < 0)
			return -1;
	}

	/*
	 *  if not ending on a sector boundary,
	 *  read in the last sector before writing it out.
	 */
	if(partial){
		if (mvsataxfer(dp, nil, Read, dp->offset+rv, dp->unit->secsize)
		    < 0)
			return -1;
		memmove(dp->buf, aa+rv, partial);
		if (mvsataxfer(dp, nil, Write, dp->offset+rv, dp->unit->secsize)
		    < 0)
			return -1;
		rv += partial;
	}
	dp->offset += rv;
	return rv;
}

/*
 * normal file server I/O interface
 */

/* result is size of d in blocks of RBUFSIZE bytes */
Devsize
mvidesize(Device *d)
{
	Drive *dp = d->private;

	if (dp == nil)
		return 0;
	/*
	 * dividing first is sloppy but reduces the range of intermediate
	 * values, avoiding possible overflow.
	 */
	return (dp->sectors / RBUFSIZE) * dp->unit->secsize;
}

void
mvideinit(Device *d)
{
	int driveno;
	Drive *dp;

	DPRINT("mvideinit\n");
	mvsatainit();
	if (d->private)
		return;
	/* call setmv50part() first in case we didn't boot off this drive */
	driveno = d->wren.ctrl*NCtlrdrv + d->wren.targ;
	DPRINT("%Z: mvideinit\n", d);
	setmv50part(driveno, "disk");
	dp = mvsatadriveprobe(driveno);
	if (dp) {
		print("mvideinit(ctrl %d targ %d) driveno %d\n",
			d->wren.ctrl, d->wren.targ, dp->driveno);
		if (dp->driveno != driveno)
			panic("mvideinit: dp->dev != driveno");
		if (dp->magic != Drvmagic)
			panic("mvideinit: %Z: bad drive magic", d);
		d->private = dp;
		if (dp->unit == nil)
			panic("mvideinit: %Z: nil dp->unit", d);
		/* print the sizes now, not later */
		print(
	"  mvidesize(driveno %d):  %llud %lud-byte sectors -> %llud blocks\n",
			dp->driveno, (Wideoff)dp->sectors, dp->unit->secsize,
			(Wideoff)mvidesize(d));
		if (dp->unit->secsize == 0)
			panic("%Z: zero sector size", d);
		if (dp->sectors == 0)
			panic("%Z: zero sectors", d);
	}
}

int
mvideread(Device *d, Devsize b, void *c)
{
	int x, driveno;
	Drive *dp;
	Ctlr *cp;

	if (d == nil || d->private == nil) {
		print("mvideread: %Z: nil d or d->private == nil\n", d);
		return 1;
	}
	dp = d->private;
	cp = dp->ctlr;
	if (cp == nil)
		panic("mvideread: no controller for drive");

	qlock(&cp->idelock);
	cp->idelock.name = "mvideio";
	driveno = dp->driveno;
	if (driveno == -1)
		panic("mvideread: dp->driveno unset");
	IDPRINT("mvideread(dev %lux, %lld, %lux, %d): %lux\n",
		(ulong)d, (Wideoff)b, (ulong)c, driveno, (ulong)dp);
	mvsataseek(driveno, b * RBUFSIZE);
	x = mvsataread(driveno, c, RBUFSIZE) != RBUFSIZE;
	qunlock(&cp->idelock);
	return x;
}

int
mvidewrite(Device *d, Devsize b, void *c)
{
	int x, driveno;
	Drive *dp;
	Ctlr *cp;

	if (d == nil || d->private == nil) {
		print("mvidewrite: %Z: nil d or d->private == nil\n", d);
		return 1;
	}
	dp = d->private;
	cp = dp->ctlr;
	if (cp == nil)
		panic("mvidewrite: no controller for drive");

	qlock(&cp->idelock);
	cp->idelock.name = "mvideio";
	driveno = dp->driveno;
	if (driveno == -1)
		panic("mvidewrite: dp->driveno unset");
	IDPRINT("mvidewrite(%ux, %lld, %ux): driveno %d\n",
		(int)d, (Wideoff)b, (int)c, driveno);
	mvsataseek(driveno, b * RBUFSIZE);
	x = mvsatawrite(driveno, c, RBUFSIZE) != RBUFSIZE;
	qunlock(&cp->idelock);
	return x;
}

static void
cmd_stat(int, char*[])
{
	Ctlr *ctlr;
	int ctlrno, targetno;
	Target *tp;

	for(ctlrno = 0; ctlrno < nelem(mvsatactlr); ctlrno++){
		ctlr = mvsatactlr[ctlrno];
		if(ctlr == nil || ctlr->sdev == nil)
			continue;
		for(targetno = 0; targetno < NTarget; targetno++){
			tp = &ctlr->target[targetno];
			if(tp->fflag == 0)
				continue;
			print("\t%d.%d work =%7W%7W%7W xfrs\n",
				ctlrno, targetno,
				tp->work+0, tp->work+1, tp->work+2);
			print("\t    rate =%7W%7W%7W tBps\n",
				tp->rate+0, tp->rate+1, tp->rate+2);
		}
	}
}

static void
statsinit(void)
{
	cmd_install("statm", "-- marvell sata stats", cmd_stat);
}

/* Tab 4 Font
* Copyright 2005
* Coraid, Inc.
*
* This software is provided `as-is,' without any express or implied
* warranty.  In no event will the author be held liable for any damages
* arising from the use of this software.
*
* Permission is granted to anyone to use this software for any purpose,
* including commercial applications, and to alter it and redistribute it
* freely, subject to the following restrictions:
*
* 1.  The origin of this software must not be misrepresented; you must
* not claim that you wrote the original software.  If you use this
* software in a product, an acknowledgment in the product documentation
* would be appreciated but is not required.
*
* 2.  Altered source versions must be plainly marked as such, and must
* not be misrepresented as being the original software.
*
* 3.  This notice may not be removed or altered from any source
* distribution.
*/