Annotation of 43BSDReno/sys/vaxmba/mba.c, revision 1.1

1.1     ! root        1: /*
        !             2:  * Copyright (c) 1982 Regents of the University of California.
        !             3:  * All rights reserved.  The Berkeley software License Agreement
        !             4:  * specifies the terms and conditions for redistribution.
        !             5:  *
        !             6:  *     @(#)mba.c       7.4 (Berkeley) 2/17/90
        !             7:  */
        !             8: 
        !             9: #include "mba.h"
        !            10: #if NMBA > 0
        !            11: /*
        !            12:  * Massbus driver, arbitrates a massbus among attached devices.
        !            13:  */
        !            14: #include "machine/pte.h"
        !            15: 
        !            16: #include "param.h"
        !            17: #include "systm.h"
        !            18: #include "dkstat.h"
        !            19: #include "buf.h"
        !            20: #include "conf.h"
        !            21: #include "user.h"
        !            22: #include "proc.h"
        !            23: #include "map.h"
        !            24: #include "../vax/mtpr.h"
        !            25: #include "vm.h"
        !            26: 
        !            27: #include "mbareg.h"
        !            28: #include "mbavar.h"
        !            29: 
        !            30: /* mbunit should be the same as hpunit, etc.! */
        !            31: #define mbunit(dev)    (minor(dev) >> 3)
        !            32: 
        !            33: char   mbsr_bits[] = MBSR_BITS;
        !            34: /*
        !            35:  * Start activity on a massbus device.
        !            36:  * We are given the device's mba_device structure and activate
        !            37:  * the device via the unit start routine.  The unit start
        !            38:  * routine may indicate that it is finished (e.g. if the operation
        !            39:  * was a ``sense'' on a tape drive), that the (multi-ported) unit
        !            40:  * is busy (we will get an interrupt later), that it started the
        !            41:  * unit (e.g. for a non-data transfer operation), or that it has
        !            42:  * set up a data transfer operation and we should start the massbus adaptor.
        !            43:  */
        !            44: mbustart(mi)
        !            45:        register struct mba_device *mi;
        !            46: {
        !            47:        register struct buf *bp;        /* i/o operation at head of queue */
        !            48:        register struct mba_hd *mhp;    /* header for mba device is on */
        !            49: 
        !            50: loop:
        !            51:        /*
        !            52:         * Get the first thing to do off device queue.
        !            53:         */
        !            54:        bp = mi->mi_tab.b_actf;
        !            55:        if (bp == NULL)
        !            56:                return;
        !            57:        /*
        !            58:         * Let the drivers unit start routine have at it
        !            59:         * and then process the request further, per its instructions.
        !            60:         */
        !            61:        switch ((*mi->mi_driver->md_ustart)(mi)) {
        !            62: 
        !            63:        case MBU_NEXT:          /* request is complete (e.g. ``sense'') */
        !            64:                mi->mi_tab.b_active = 0;
        !            65:                mi->mi_tab.b_errcnt = 0;
        !            66:                mi->mi_tab.b_actf = bp->av_forw;
        !            67:                biodone(bp);
        !            68:                goto loop;
        !            69: 
        !            70:        case MBU_DODATA:        /* all ready to do data transfer */
        !            71:                /*
        !            72:                 * Queue the device mba_device structure on the massbus
        !            73:                 * mba_hd structure for processing as soon as the
        !            74:                 * data path is available.
        !            75:                 */
        !            76:                mhp = mi->mi_hd;
        !            77:                mi->mi_forw = NULL;
        !            78:                if (mhp->mh_actf == NULL)
        !            79:                        mhp->mh_actf = mi;
        !            80:                else
        !            81:                        mhp->mh_actl->mi_forw = mi;
        !            82:                mhp->mh_actl = mi;
        !            83:                /*
        !            84:                 * If data path is idle, start transfer now.
        !            85:                 * In any case the device is ``active'' waiting for the
        !            86:                 * data to transfer.
        !            87:                 */
        !            88:                mi->mi_tab.b_active = 1;
        !            89:                if (mhp->mh_active == 0)
        !            90:                        mbstart(mhp);
        !            91:                return;
        !            92: 
        !            93:        case MBU_STARTED:       /* driver started a non-data transfer */
        !            94:                /*
        !            95:                 * Mark device busy during non-data transfer
        !            96:                 * and count this as a ``seek'' on the device.
        !            97:                 */
        !            98:                if (mi->mi_dk >= 0) {
        !            99:                        dk_seek[mi->mi_dk]++;
        !           100:                        dk_busy |= (1 << mi->mi_dk);
        !           101:                }
        !           102:                mi->mi_tab.b_active = 1;
        !           103:                return;
        !           104: 
        !           105:        case MBU_BUSY:          /* dual port drive busy */
        !           106:                /*
        !           107:                 * We mark the device structure so that when an
        !           108:                 * interrupt occurs we will know to restart the unit.
        !           109:                 */
        !           110:                mi->mi_tab.b_flags |= B_BUSY;
        !           111:                return;
        !           112: 
        !           113:        default:
        !           114:                panic("mbustart");
        !           115:        }
        !           116: }
        !           117: 
        !           118: /*
        !           119:  * Start an i/o operation on the massbus specified by the argument.
        !           120:  * We peel the first operation off its queue and insure that the drive
        !           121:  * is present and on-line.  We then use the drivers start routine
        !           122:  * (if any) to prepare the drive, setup the massbus map for the transfer
        !           123:  * and start the transfer.
        !           124:  */
        !           125: mbstart(mhp)
        !           126:        register struct mba_hd *mhp;
        !           127: {
        !           128:        register struct mba_device *mi;
        !           129:        struct buf *bp;
        !           130:        register struct mba_regs *mbp;
        !           131:        register int com;
        !           132:        extern int cold;
        !           133: 
        !           134: loop:
        !           135:        /*
        !           136:         * Look for an operation at the front of the queue.
        !           137:         */
        !           138:        if ((mi = mhp->mh_actf) == NULL) {
        !           139:                return;
        !           140:        }
        !           141:        if ((bp = mi->mi_tab.b_actf) == NULL) {
        !           142:                mhp->mh_actf = mi->mi_forw;
        !           143:                goto loop;
        !           144:        }
        !           145:        /*
        !           146:         * If this device isn't present and on-line, then
        !           147:         * we screwed up, and can't really do the operation.
        !           148:         * Only check for non-tapes because tape drivers check
        !           149:         * ONLINE themselves and because TU78 registers are
        !           150:         * different.
        !           151:         * No complaints during autoconfiguration,
        !           152:         * when we try to read disk labels from anything on line.
        !           153:         */
        !           154:        if (((com = mi->mi_drv->mbd_dt) & MBDT_TAP) == 0)
        !           155:        if ((mi->mi_drv->mbd_ds & MBDS_DREADY) != MBDS_DREADY) {
        !           156:                if (!cold) {
        !           157:                    if ((com & MBDT_TYPE) == 0) {
        !           158:                        mi->mi_alive = 0;
        !           159:                        printf("%s%d: nonexistent\n", mi->mi_driver->md_dname,
        !           160:                            mbunit(bp->b_dev));
        !           161:                    } else
        !           162:                        printf("%s%d: not ready\n", mi->mi_driver->md_dname,
        !           163:                            mbunit(bp->b_dev));
        !           164:                }
        !           165:                mi->mi_tab.b_actf = bp->av_forw;
        !           166:                mi->mi_tab.b_errcnt = 0;
        !           167:                mi->mi_tab.b_active = 0;
        !           168:                bp->b_flags |= B_ERROR;
        !           169:                biodone(bp);
        !           170:                goto loop;
        !           171:        }
        !           172:        /*
        !           173:         * We can do the operation; mark the massbus active
        !           174:         * and let the device start routine setup any necessary
        !           175:         * device state for the transfer (e.g. desired cylinder, etc
        !           176:         * on disks).
        !           177:         */
        !           178:        mhp->mh_active = 1;
        !           179:        if (mi->mi_driver->md_start == (int (*)())0 ||
        !           180:            (com = (*mi->mi_driver->md_start)(mi)) == 0)
        !           181:                com = (bp->b_flags & B_READ) ? MB_RCOM|MB_GO : MB_WCOM|MB_GO;
        !           182: 
        !           183:        /*
        !           184:         * Setup the massbus control and map registers and start
        !           185:         * the transfer.
        !           186:         */
        !           187:        mbp = mi->mi_mba;
        !           188:        mbp->mba_sr = -1;       /* conservative */
        !           189:        if (bp->b_bcount >= 0) {
        !           190:                mbp->mba_var = mbasetup(mi) + mi->mi_tab.b_bdone;
        !           191:                mbp->mba_bcr = -(bp->b_bcount - mi->mi_tab.b_bdone);
        !           192:        } else {
        !           193:                mbp->mba_var = mbasetup(mi) - bp->b_bcount - mi->mi_tab.b_bdone - 1;
        !           194:                mbp->mba_bcr = bp->b_bcount + mi->mi_tab.b_bdone;
        !           195:        }
        !           196:        mi->mi_drv->mbd_cs1 = com;
        !           197:        if (mi->mi_dk >= 0) {
        !           198:                dk_busy |= 1 << mi->mi_dk;
        !           199:                dk_xfer[mi->mi_dk]++;
        !           200:                if (bp->b_bcount >= 0)
        !           201:                        dk_wds[mi->mi_dk] += bp->b_bcount >> 6;
        !           202:                else
        !           203:                        dk_wds[mi->mi_dk] += -(bp->b_bcount) >> 6;
        !           204:        }
        !           205: }
        !           206: 
        !           207: /*
        !           208:  * Take an interrupt off of massbus mbanum,
        !           209:  * and dispatch to drivers as appropriate.
        !           210:  */
        !           211: mbintr(mbanum)
        !           212:        int mbanum;
        !           213: {
        !           214:        register struct mba_hd *mhp = &mba_hd[mbanum];
        !           215:        register struct mba_regs *mbp = mhp->mh_mba;
        !           216:        register struct mba_device *mi;
        !           217:        register struct buf *bp;
        !           218:        register int drive;
        !           219:        int mbasr, as;
        !           220:        extern struct mba_device *mbaconfig();
        !           221:        
        !           222:        /*
        !           223:         * Read out the massbus status register
        !           224:         * and attention status register and clear
        !           225:         * the bits in same by writing them back.
        !           226:         */
        !           227:        mbasr = mbp->mba_sr;
        !           228:        mbp->mba_sr = mbasr;
        !           229: #if VAX750
        !           230:        if (mbasr&MBSR_CBHUNG) {
        !           231:                printf("mba%d: control bus hung\n", mbanum);
        !           232:                panic("cbhung");
        !           233:        }
        !           234: #endif
        !           235:        /* note: the mbd_as register is shared between drives */
        !           236:        as = mbp->mba_drv[0].mbd_as & 0xff;
        !           237:        mbp->mba_drv[0].mbd_as = as;
        !           238: 
        !           239:        /*
        !           240:         * If the mba was active, process the data transfer
        !           241:         * complete interrupt; otherwise just process units which
        !           242:         * are now finished.
        !           243:         */
        !           244:        if (mhp->mh_active) {
        !           245:                /*
        !           246:                 * Clear attention status for drive whose data
        !           247:                 * transfer related operation completed,
        !           248:                 * and give the dtint driver
        !           249:                 * routine a chance to say what is next.
        !           250:                 */
        !           251:                mi = mhp->mh_actf;
        !           252:                as &= ~(1 << mi->mi_drive);
        !           253:                dk_busy &= ~(1 << mi->mi_dk);
        !           254:                bp = mi->mi_tab.b_actf;
        !           255:                switch ((*mi->mi_driver->md_dtint)(mi, mbasr)) {
        !           256: 
        !           257:                case MBD_DONE:          /* all done, for better or worse */
        !           258:                        /*
        !           259:                         * Flush request from drive queue.
        !           260:                         */
        !           261:                        mi->mi_tab.b_errcnt = 0;
        !           262:                        mi->mi_tab.b_actf = bp->av_forw;
        !           263:                        biodone(bp);
        !           264:                        /* fall into... */
        !           265:                case MBD_RETRY:         /* attempt the operation again */
        !           266:                        /*
        !           267:                         * Dequeue data transfer from massbus queue;
        !           268:                         * if there is still a i/o request on the device
        !           269:                         * queue then start the next operation on the device.
        !           270:                         * (Common code for DONE and RETRY).
        !           271:                         */
        !           272:                        mhp->mh_active = 0;
        !           273:                        mi->mi_tab.b_active = 0;
        !           274:                        mhp->mh_actf = mi->mi_forw;
        !           275:                        if (mi->mi_tab.b_actf)
        !           276:                                mbustart(mi);
        !           277:                        break;
        !           278: 
        !           279:                case MBD_REPOSITION:    /* driver started repositioning */
        !           280:                        /*
        !           281:                         * Drive is repositioning, not doing data transfer.
        !           282:                         * Free controller, but don't have to restart drive.
        !           283:                         */
        !           284:                        mhp->mh_active = 0;
        !           285:                        mhp->mh_actf = mi->mi_forw;
        !           286:                        break;
        !           287: 
        !           288:                case MBD_RESTARTED:     /* driver restarted op (ecc, e.g.) */
        !           289:                        /*
        !           290:                         * Note that mhp->mh_active is still on.
        !           291:                         */
        !           292:                        break;
        !           293: 
        !           294:                default:
        !           295:                        panic("mbintr");
        !           296:                }
        !           297:        }
        !           298:        /*
        !           299:         * Service drives which require attention
        !           300:         * after non-data-transfer operations.
        !           301:         */
        !           302:        while (drive = ffs((long)as)) {
        !           303:                drive--;                /* was 1 origin */
        !           304:                as &= ~(1 << drive);
        !           305:                mi = mhp->mh_mbip[drive];
        !           306:                if (mi == NULL || mi->mi_alive == 0) {
        !           307:                        struct mba_device fnd;
        !           308:                        struct mba_drv *mbd = &mhp->mh_mba->mba_drv[drive];
        !           309:                        int dt = mbd->mbd_dt & 0xffff;
        !           310: 
        !           311:                        if (dt == 0 || dt == MBDT_MOH)
        !           312:                                continue;
        !           313:                        fnd.mi_mba = mhp->mh_mba;
        !           314:                        fnd.mi_mbanum = mbanum;
        !           315:                        fnd.mi_drive = drive;
        !           316:                        if ((mi = mbaconfig(&fnd, dt)) == NULL)
        !           317:                                continue;
        !           318:                        /*
        !           319:                         * If a tape, poke the slave attach routines.
        !           320:                         * Otherwise, could be a disk which we want
        !           321:                         * to swap on, so make a pass over the swap
        !           322:                         * configuration table in case the size of
        !           323:                         * the swap area must be determined by drive type.
        !           324:                         */
        !           325:                        if (dt & MBDT_TAP)
        !           326:                                mbaddtape(mi, drive);
        !           327:                        else
        !           328:                                swapconf();
        !           329:                }
        !           330:                /*
        !           331:                 * If driver has a handler for non-data transfer
        !           332:                 * interrupts, give it a chance to tell us what to do.
        !           333:                 */
        !           334:                if (mi->mi_driver->md_ndint) {
        !           335:                        switch ((*mi->mi_driver->md_ndint)(mi)) {
        !           336: 
        !           337:                        case MBN_DONE:          /* operation completed */
        !           338:                                mi->mi_tab.b_active = 0;
        !           339:                                mi->mi_tab.b_errcnt = 0;
        !           340:                                bp = mi->mi_tab.b_actf;
        !           341:                                mi->mi_tab.b_actf = bp->av_forw;
        !           342:                                biodone(bp);
        !           343:                                /* fall into common code */
        !           344:                        case MBN_RETRY:         /* operation continues */
        !           345:                                if (mi->mi_tab.b_actf)
        !           346:                                        mbustart(mi);
        !           347:                                break;
        !           348:                        case MBN_SKIP:          /* ignore unsol. interrupt */
        !           349:                                break;
        !           350:                        default:
        !           351:                                panic("mbintr");
        !           352:                        }
        !           353:                } else
        !           354:                        /*
        !           355:                         * If there is no non-data transfer interrupt
        !           356:                         * routine, then we should just
        !           357:                         * restart the unit, leading to a mbstart() soon.
        !           358:                         */
        !           359:                        mbustart(mi);
        !           360:        }
        !           361:        /*
        !           362:         * If there is an operation available and
        !           363:         * the massbus isn't active, get it going.
        !           364:         */
        !           365:        if (mhp->mh_actf && !mhp->mh_active)
        !           366:                mbstart(mhp);
        !           367:        /* THHHHATS all folks... */
        !           368: }
        !           369: 
        !           370: /*
        !           371:  * For autoconfig'ng tape drives on the fly.
        !           372:  */
        !           373: mbaddtape(mi, drive)
        !           374:        struct mba_device *mi;
        !           375:        int drive;
        !           376: {
        !           377:        register struct mba_slave *ms;
        !           378: 
        !           379:        for (ms = mbsinit; ms->ms_driver; ms++)
        !           380:                if (ms->ms_driver == mi->mi_driver && ms->ms_alive == 0 && 
        !           381:                    (ms->ms_ctlr == mi->mi_unit ||
        !           382:                     ms->ms_ctlr == '?')) {
        !           383:                        if ((*ms->ms_driver->md_slave)(mi, ms, drive)) {
        !           384:                                printf("%s%d at %s%d slave %d\n",
        !           385:                                    ms->ms_driver->md_sname,
        !           386:                                    ms->ms_unit,
        !           387:                                    mi->mi_driver->md_dname,
        !           388:                                    mi->mi_unit,
        !           389:                                    ms->ms_slave);
        !           390:                                ms->ms_alive = 1;
        !           391:                                ms->ms_ctlr = mi->mi_unit;
        !           392:                        }
        !           393:                }
        !           394: }
        !           395: 
        !           396: /*
        !           397:  * Setup the mapping registers for a transfer.
        !           398:  */
        !           399: mbasetup(mi)
        !           400:        register struct mba_device *mi;
        !           401: {
        !           402:        register struct mba_regs *mbap = mi->mi_mba;
        !           403:        struct buf *bp = mi->mi_tab.b_actf;
        !           404:        register int npf;
        !           405:        unsigned v;
        !           406:        register struct pte *pte, *io;
        !           407:        int o;
        !           408:        struct proc *rp;
        !           409: 
        !           410:        v = btop(bp->b_un.b_addr);
        !           411:        o = (int)(bp->b_un.b_addr) & PGOFSET;
        !           412:        if (bp->b_bcount >= 0)
        !           413:                npf = btoc(bp->b_bcount + o);
        !           414:        else
        !           415:                npf = btoc(-(bp->b_bcount) + o);
        !           416:        rp = bp->b_flags&B_DIRTY ? &proc[2] : bp->b_proc;
        !           417:        if ((bp->b_flags & B_PHYS) == 0)
        !           418:                pte = &Sysmap[btop(((int)bp->b_un.b_addr)&0x7fffffff)];
        !           419:        else if (bp->b_flags & B_UAREA)
        !           420:                pte = &rp->p_addr[v];
        !           421:        else if (bp->b_flags & B_PAGET)
        !           422:                pte = &Usrptmap[btokmx((struct pte *)bp->b_un.b_addr)];
        !           423:        else
        !           424:                pte = vtopte(rp, v);
        !           425:        io = mbap->mba_map;
        !           426:        while (--npf >= 0) {
        !           427:                if (pte->pg_pfnum == 0)
        !           428:                        panic("mba, zero entry");
        !           429:                *(int *)io++ = pte++->pg_pfnum | PG_V;
        !           430:        }
        !           431:        *(int *)io++ = 0;
        !           432:        return (o);
        !           433: }
        !           434: 
        !           435: #if notdef
        !           436: /*
        !           437:  * Init and interrupt enable a massbus adapter.
        !           438:  */
        !           439: mbainit(mp)
        !           440:        struct mba_regs *mp;
        !           441: {
        !           442: 
        !           443:        mp->mba_cr = MBCR_INIT;
        !           444:        mp->mba_cr = MBCR_IE;
        !           445: }
        !           446: #endif
        !           447: #endif

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