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sbic.c revision 1.8
      1 /*	$NetBSD: sbic.c,v 1.8 1998/08/22 10:55:33 scw Exp $	*/
      2 
      3 /*
      4  * Changes Copyright (c) 1996 Steve Woodford
      5  * Original Copyright (c) 1994 Christian E. Hopps
      6  * Copyright (c) 1990 The Regents of the University of California.
      7  * All rights reserved.
      8  *
      9  * This code is derived from software contributed to Berkeley by
     10  * Van Jacobson of Lawrence Berkeley Laboratory.
     11  *
     12  * Redistribution and use in source and binary forms, with or without
     13  * modification, are permitted provided that the following conditions
     14  * are met:
     15  * 1. Redistributions of source code must retain the above copyright
     16  *    notice, this list of conditions and the following disclaimer.
     17  * 2. Redistributions in binary form must reproduce the above copyright
     18  *    notice, this list of conditions and the following disclaimer in the
     19  *    documentation and/or other materials provided with the distribution.
     20  * 3. All advertising materials mentioning features or use of this software
     21  *    must display the following acknowledgement:
     22  *  This product includes software developed by the University of
     23  *  California, Berkeley and its contributors.
     24  * 4. Neither the name of the University nor the names of its contributors
     25  *    may be used to endorse or promote products derived from this software
     26  *    without specific prior written permission.
     27  *
     28  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     29  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     30  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     31  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     32  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     33  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     34  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     35  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     36  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     37  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     38  * SUCH DAMAGE.
     39  *
     40  *  @(#)scsi.c  7.5 (Berkeley) 5/4/91
     41  */
     42 
     43 /*
     44  * Steve Woodford (SCW), Apr, 1996
     45  * MVME147S WD33C93 Scsi Bus Interface Controller driver,
     46  *
     47  * Basically a de-loused and tidied up version of the Amiga AMD 33C93 driver.
     48  *
     49  * The original driver used features which required at least a WD33C93A
     50  * chip. The '147 has the original WD33C93 chip (no 'A' suffix).
     51  *
     52  * This version of the driver is pretty well generic, so should work with
     53  * any flavour of WD33C93 chip.
     54  */
     55 #include "opt_ddb.h"
     56 
     57 #include <sys/param.h>
     58 #include <sys/systm.h>
     59 #include <sys/device.h>
     60 #include <sys/kernel.h> /* For hz */
     61 #include <sys/disklabel.h>
     62 #include <sys/dkstat.h>
     63 #include <sys/buf.h>
     64 #include <dev/scsipi/scsi_all.h>
     65 #include <dev/scsipi/scsipi_all.h>
     66 #include <dev/scsipi/scsiconf.h>
     67 #include <vm/vm.h>
     68 #include <vm/vm_kern.h>
     69 #include <vm/vm_page.h>
     70 #include <vm/pmap.h>
     71 #include <machine/pmap.h>
     72 #include <mvme68k/mvme68k/isr.h>
     73 #include <mvme68k/dev/dmavar.h>
     74 #include <mvme68k/dev/sbicreg.h>
     75 #include <mvme68k/dev/sbicvar.h>
     76 
     77 
     78 /*
     79  * Since I can't find this in any other header files
     80  */
     81 #define SCSI_PHASE(reg) (reg&0x07)
     82 
     83 /*
     84  * SCSI delays
     85  * In u-seconds, primarily for state changes on the SPC.
     86  */
     87 #define SBIC_CMD_WAIT   50000   /* wait per step of 'immediate' cmds */
     88 #define SBIC_DATA_WAIT  50000   /* wait per data in/out step */
     89 #define SBIC_INIT_WAIT  50000   /* wait per step (both) during init */
     90 
     91 /*
     92  * Convenience macro for waiting for a particular sbic event
     93  */
     94 #define SBIC_WAIT(regs, until, timeo) sbicwait(regs, until, timeo, __LINE__)
     95 
     96 extern u_int kvtop();
     97 
     98 int     sbicicmd            __P((struct sbic_softc *, void *, int, void *, int));
     99 int     sbicgo              __P((struct sbic_softc *, struct scsipi_xfer *));
    100 int     sbicdmaok           __P((struct sbic_softc *, struct scsipi_xfer *));
    101 int     sbicwait            __P((sbic_regmap_p, u_char, int , int));
    102 int     sbiccheckdmap       __P((void *, u_long, u_long));
    103 u_char  sbicselectbus       __P((struct sbic_softc *));
    104 int     sbicxfout           __P((sbic_regmap_p, int, void *));
    105 int     sbicxfin            __P((sbic_regmap_p, int, void *));
    106 int     sbicfromscsiperiod  __P((struct sbic_softc *, int));
    107 int     sbictoscsiperiod    __P((struct sbic_softc *, int));
    108 int     sbicintr            __P((struct sbic_softc *));
    109 int     sbicpoll            __P((struct sbic_softc *));
    110 int     sbicnextstate       __P((struct sbic_softc *, u_char, u_char));
    111 int     sbicmsgin           __P((struct sbic_softc *));
    112 int     sbicabort           __P((struct sbic_softc *, char *));
    113 void    sbicxfdone          __P((struct sbic_softc *));
    114 void    sbicerror           __P((struct sbic_softc *,u_char));
    115 void    sbicreset           __P((struct sbic_softc *));
    116 void    sbic_scsidone       __P((struct sbic_acb *, int));
    117 void    sbic_sched          __P((struct sbic_softc *));
    118 void    sbic_save_ptrs      __P((struct sbic_softc *));
    119 void    sbic_load_ptrs      __P((struct sbic_softc *));
    120 
    121 /*
    122  * Synch xfer parameters, and timing conversions
    123  */
    124 int     sbic_min_period = SBIC_SYN_MIN_PERIOD;  /* in cycles = f(ICLK,FSn) */
    125 int     sbic_max_offset = SBIC_SYN_MAX_OFFSET;  /* pure number */
    126 int     sbic_cmd_wait   = SBIC_CMD_WAIT;
    127 int     sbic_data_wait  = SBIC_DATA_WAIT;
    128 int     sbic_init_wait  = SBIC_INIT_WAIT;
    129 
    130 /*
    131  * was broken before.. now if you want this you get it for all drives
    132  * on sbic controllers.
    133  */
    134 u_char  sbic_inhibit_sync[8];
    135 int     sbic_enable_reselect     = 1;   /* Allow Disconnect / Reselect */
    136 int     sbic_no_dma              = 0;   /* Use PIO transfers instead of DMA */
    137 int     sbic_parallel_operations = 1;   /* Allow command queues */
    138 
    139 /*
    140  * Some useful stuff for debugging purposes
    141  */
    142 #ifdef DEBUG
    143 int     sbicdma_ops     = 0;    /* total DMA operations */
    144 int     sbicdma_hits    = 0;    /* number of DMA chains that were contiguous */
    145 int     sbicdma_misses  = 0;    /* number of DMA chains that were not contiguous */
    146 int     sbicdma_saves   = 0;
    147 
    148 #define QPRINTF(a) if (sbic_debug > 1) printf a
    149 
    150 int     sbic_debug      = 0;    /* Debug all chip related things */
    151 int     sync_debug      = 0;    /* Debug all Synchronous Scsi related things */
    152 int     reselect_debug  = 0;    /* Debug all reselection related things */
    153 int     report_sense    = 0;    /* Always print Sense information */
    154 int     data_pointer_debug = 0; /* Debug Data Pointer related things */
    155 
    156 void    sbictimeout __P((struct sbic_softc *dev));
    157 
    158 #else
    159 #define QPRINTF(a)  /* */
    160 #endif
    161 
    162 
    163 /*
    164  * default minphys routine for sbic based controllers
    165  */
    166 void
    167 sbic_minphys(bp)
    168     struct buf *bp;
    169 {
    170     /*
    171      * No max transfer at this level.
    172      */
    173     minphys(bp);
    174 }
    175 
    176 
    177 /*
    178  * Save DMA pointers.  Take into account partial transfer. Shut down DMA.
    179  */
    180 void
    181 sbic_save_ptrs(dev)
    182     struct sbic_softc   *dev;
    183 {
    184     sbic_regmap_p       regs;
    185     struct sbic_acb*    acb;
    186     int                 count,
    187                         asr,
    188                         s;
    189 
    190     /*
    191      * Only need to save pointers if DMA was active...
    192      */
    193     if ( dev->sc_cur == NULL || (dev->sc_flags & SBICF_INDMA) == 0 )
    194         return;
    195 
    196     regs = dev->sc_sbicp;
    197 
    198     s = splbio();
    199 
    200     /*
    201      * Wait until WD chip is idle
    202      */
    203     do {
    204         GET_SBIC_asr(regs, asr);
    205         if( asr & SBIC_ASR_DBR ) {
    206             printf("sbic_save_ptrs: asr %02x canceled!\n", asr);
    207             splx(s);
    208             return;
    209         }
    210     } while( asr & (SBIC_ASR_BSY|SBIC_ASR_CIP) );
    211 
    212 
    213     /*
    214      * Save important state.
    215      * must be done before dmastop
    216      */
    217     acb            = dev->sc_nexus;
    218     acb->sc_dmacmd = dev->sc_dmacmd;
    219 
    220     /*
    221      * Fetch the residual count
    222      */
    223     SBIC_TC_GET(regs, count);
    224 
    225     /*
    226      * Shut down DMA
    227      */
    228     dev->sc_dmastop(dev);
    229 
    230     /*
    231      * No longer in DMA
    232      */
    233     dev->sc_flags &= ~SBICF_INDMA;
    234 
    235     /*
    236      * Ensure the WD chip is back in polled I/O mode, with nothing to
    237      * transfer.
    238      */
    239     SBIC_TC_PUT(regs, 0);
    240     SET_SBIC_control(regs, SBIC_CTL_EDI | SBIC_CTL_IDI);
    241 
    242     /*
    243      * Update current count...
    244      */
    245     acb->sc_tcnt = count;
    246 
    247     /*
    248      * Work out how many bytes were actually transferred
    249      */
    250     count        = dev->sc_tcnt - count;
    251     dev->sc_tcnt = acb->sc_tcnt;
    252 
    253     /*
    254      * Fixup partial xfers
    255      */
    256     acb->sc_kv.dc_addr  += count;
    257     acb->sc_kv.dc_count -= count;
    258     acb->sc_pa.dc_addr  += count;
    259     acb->sc_pa.dc_count -= count >> 1;
    260 
    261 #ifdef DEBUG
    262     if ( data_pointer_debug )
    263         printf("save at (%x,%x):%x\n",
    264                dev->sc_cur->dc_addr, dev->sc_cur->dc_count,count);
    265     sbicdma_saves++;
    266 #endif
    267 
    268     splx(s);
    269 }
    270 
    271 
    272 /*
    273  * DOES NOT RESTART DMA!!!
    274  */
    275 void
    276 sbic_load_ptrs(dev)
    277     struct sbic_softc   *dev;
    278 {
    279     struct sbic_acb *acb = dev->sc_nexus;
    280     int             s;
    281 
    282     if ( acb->sc_kv.dc_count == 0 ) {
    283         /*
    284          * No data to xfer
    285          */
    286         return;
    287     }
    288 
    289     s = splbio();
    290 
    291     /*
    292      * Reset the Scatter-Gather chain
    293      */
    294     dev->sc_last = dev->sc_cur = &acb->sc_pa;
    295 
    296     /*
    297      * Restore the Transfer Count and DMA specific data
    298      */
    299     dev->sc_tcnt   = acb->sc_tcnt;
    300     dev->sc_dmacmd = acb->sc_dmacmd;
    301 
    302 #ifdef DEBUG
    303     sbicdma_ops++;
    304 #endif
    305 
    306     /*
    307      * Need to fixup new segment?
    308      */
    309     if ( dev->sc_tcnt == 0 ) {
    310         /*
    311          * sc_tcnt == 0 implies end of segment
    312          */
    313         char    *vaddr, *paddr;
    314         int     count;
    315 
    316         /*
    317          * do kvm to pa mappings
    318          */
    319         vaddr = acb->sc_kv.dc_addr;
    320         paddr = acb->sc_pa.dc_addr = (char *) kvtop(vaddr);
    321 
    322         for (count = (NBPG - ((int)vaddr & PGOFSET));
    323              count < acb->sc_kv.dc_count &&
    324                      (char*)kvtop(vaddr + count + 4) == paddr + count + 4;
    325              count += NBPG)
    326             ;   /* Do nothing */
    327 
    328         /*
    329          * If it's all contiguous...
    330          */
    331         if ( count > acb->sc_kv.dc_count ) {
    332             count = acb->sc_kv.dc_count;
    333 #ifdef  DEBUG
    334             sbicdma_hits++;
    335 #endif
    336         }
    337 #ifdef  DEBUG
    338         else
    339             sbicdma_misses++;
    340 #endif
    341 
    342         acb->sc_tcnt        = count;
    343         acb->sc_pa.dc_count = count >> 1;
    344 
    345 #ifdef DEBUG
    346         if ( data_pointer_debug )
    347             printf("DMA recalc:kv(%x,%x)pa(%x,%x)\n", acb->sc_kv.dc_addr,
    348                                                       acb->sc_kv.dc_count,
    349                                                       acb->sc_pa.dc_addr,
    350                                                       acb->sc_tcnt);
    351 #endif
    352 
    353     }
    354 
    355     splx(s);
    356 }
    357 
    358 /*
    359  * used by specific sbic controller
    360  *
    361  * it appears that the higher level code does nothing with LUN's
    362  * so I will too.  I could plug it in, however so could they
    363  * in scsi_scsipi_cmd().
    364  */
    365 int
    366 sbic_scsicmd(xs)
    367     struct scsipi_xfer *xs;
    368 {
    369     struct scsipi_link    *slp = xs->sc_link;
    370     struct sbic_softc   *dev = slp->adapter_softc;
    371     struct sbic_acb     *acb;
    372     int                 flags = xs->flags,
    373                         s;
    374 
    375     if ( flags & SCSI_DATA_UIO )
    376         panic("sbic: scsi data uio requested");
    377 
    378     if ( dev->sc_nexus && (flags & SCSI_POLL) )
    379         panic("sbic_scsicmd: busy");
    380 
    381     if ( slp->scsipi_scsi.target == slp->scsipi_scsi.adapter_target )
    382         return ESCAPE_NOT_SUPPORTED;
    383 
    384     s = splbio();
    385 
    386     if ( (acb = dev->free_list.tqh_first) != NULL )
    387         TAILQ_REMOVE(&dev->free_list, acb, chain);
    388 
    389     splx(s);
    390 
    391     if ( acb == NULL ) {
    392 #ifdef DEBUG
    393         printf("sbic_scsicmd: unable to queue request for target %d\n",
    394             slp->scsipi_scsi.target);
    395 #ifdef DDB
    396         Debugger();
    397 #endif
    398 #endif
    399         xs->error = XS_DRIVER_STUFFUP;
    400 
    401         return(TRY_AGAIN_LATER);
    402     }
    403 
    404     if ( flags & SCSI_DATA_IN )
    405         acb->flags = ACB_ACTIVE | ACB_DATAIN;
    406     else
    407         acb->flags = ACB_ACTIVE;
    408 
    409     acb->xs             = xs;
    410     acb->clen           = xs->cmdlen;
    411     acb->sc_kv.dc_addr  = xs->data;
    412     acb->sc_kv.dc_count = xs->datalen;
    413     acb->pa_addr        = xs->data ? (char *)kvtop(xs->data) : 0;
    414     bcopy(xs->cmd, &acb->cmd, xs->cmdlen);
    415 
    416     if ( flags & SCSI_POLL ) {
    417         /*
    418          * This has major side effects -- it locks up the machine
    419          */
    420         int stat;
    421 
    422         s = splbio();
    423 
    424         dev->sc_flags |= SBICF_ICMD;
    425 
    426         do {
    427             /*
    428              * If we already had a nexus, while away the time until idle...
    429              * This is likely only to happen if a reselection occurs between
    430              * here and our earlier check for ICMD && sc_nexus (which would
    431              * have resulted in a panic() had it been true).
    432              */
    433             while ( dev->sc_nexus )
    434                 sbicpoll(dev);
    435 
    436             /*
    437              * Fix up the new nexus
    438              */
    439             dev->sc_nexus   = acb;
    440             dev->sc_xs      = xs;
    441             dev->target     = slp->scsipi_scsi.target;
    442             dev->lun        = slp->scsipi_scsi.lun;
    443 
    444             stat = sbicicmd(dev, &acb->cmd, acb->clen,
    445                             acb->sc_kv.dc_addr, acb->sc_kv.dc_count);
    446 
    447         } while ( dev->sc_nexus != acb );
    448 
    449         sbic_scsidone(acb, stat);
    450 
    451         splx(s);
    452 
    453         return(COMPLETE);
    454     }
    455 
    456     s = splbio();
    457     TAILQ_INSERT_TAIL(&dev->ready_list, acb, chain);
    458 
    459     /*
    460      * If nothing is active, try to start it now.
    461      */
    462     if ( dev->sc_nexus == NULL )
    463         sbic_sched(dev);
    464 
    465     splx(s);
    466 
    467     return(SUCCESSFULLY_QUEUED);
    468 }
    469 
    470 /*
    471  * attempt to start the next available command
    472  */
    473 void
    474 sbic_sched(dev)
    475     struct sbic_softc *dev;
    476 {
    477     struct scsipi_xfer    *xs;
    478     struct scsipi_link    *slp = NULL;    /* Gag the compiler */
    479     struct sbic_acb     *acb;
    480     int                 flags,
    481                         stat;
    482 
    483     /*
    484      * XXXSCW
    485      * I'll keep this test here, even though I can't see any obvious way
    486      * in which sbic_sched() could be called with sc_nexus non NULL
    487      */
    488     if ( dev->sc_nexus )
    489         return;         /* a command is current active */
    490 
    491     /*
    492      * Loop through the ready list looking for work to do...
    493      */
    494     for (acb = dev->ready_list.tqh_first; acb; acb = acb->chain.tqe_next) {
    495         int     i, j;
    496 
    497         slp = acb->xs->sc_link;
    498         i   = slp->scsipi_scsi.target;
    499         j   = 1 << slp->scsipi_scsi.lun;
    500 
    501         /*
    502          * We've found a potential command, but is the target/lun busy?
    503          */
    504         if ( (dev->sc_tinfo[i].lubusy & j) == 0 ) {
    505             /*
    506              * Nope, it's not busy, so we can use it.
    507              */
    508             dev->sc_tinfo[i].lubusy |= j;
    509             TAILQ_REMOVE(&dev->ready_list, acb, chain);
    510             dev->sc_nexus = acb;
    511             acb->sc_pa.dc_addr = acb->pa_addr;  /* XXXX check */
    512             break;
    513         }
    514     }
    515 
    516     if ( acb == NULL ) {
    517         QPRINTF(("sbicsched: no work\n"));
    518         return;         /* did not find an available command */
    519     }
    520 
    521 #ifdef DEBUG
    522     if ( data_pointer_debug > 1 )
    523         printf("sbic_sched(%d,%d)\n", slp->scsipi_scsi.target,
    524 			slp->scsipi_scsi.lun);
    525 #endif
    526 
    527     dev->sc_xs = xs = acb->xs;
    528     flags      = xs->flags;
    529 
    530     if ( flags & SCSI_RESET )
    531         sbicreset(dev);
    532 
    533     dev->sc_stat[0] = -1;
    534     dev->target     = slp->scsipi_scsi.target;
    535     dev->lun        = slp->scsipi_scsi.lun;
    536 
    537     if ( flags & SCSI_POLL || (!sbic_parallel_operations &&
    538                               (sbicdmaok(dev, xs) == 0)) )
    539         stat = sbicicmd(dev, &acb->cmd, acb->clen,
    540                         acb->sc_kv.dc_addr, acb->sc_kv.dc_count);
    541     else
    542     if ( sbicgo(dev, xs) == 0 )
    543         return;
    544     else
    545         stat = dev->sc_stat[0];
    546 
    547     sbic_scsidone(acb, stat);
    548 }
    549 
    550 void
    551 sbic_scsidone(acb, stat)
    552     struct sbic_acb *acb;
    553     int             stat;
    554 {
    555     struct scsipi_xfer    *xs  = acb->xs;
    556     struct scsipi_link    *slp = xs->sc_link;
    557     struct sbic_softc   *dev = slp->adapter_softc;
    558     int                 dosched = 0;
    559 
    560 #ifdef DIAGNOSTIC
    561     if ( acb == NULL || xs == NULL ) {
    562         printf("sbic_scsidone -- (%d,%d) no scsipi_xfer\n", dev->target, dev->lun);
    563 #ifdef DDB
    564         Debugger();
    565 #endif
    566         return;
    567     }
    568 #endif
    569 
    570     /*
    571      * is this right?
    572      */
    573     xs->status = stat;
    574 
    575 #ifdef DEBUG
    576     if ( data_pointer_debug > 1 )
    577         printf("scsidone: (%d,%d)->(%d,%d)%02x\n", slp->scsipi_scsi.target,
    578 			slp->scsipi_scsi.lun,
    579                                                    dev->target, dev->lun, stat);
    580 
    581     if ( xs->sc_link->scsipi_scsi.target ==
    582 		dev->sc_link.scsipi_scsi.adapter_target )
    583         panic("target == hostid");
    584 #endif
    585 
    586     if ( xs->error == XS_NOERROR && (acb->flags & ACB_CHKSENSE) == 0 ) {
    587 
    588         if ( stat == SCSI_CHECK ) {
    589             /*
    590              * Schedule a REQUEST SENSE
    591              */
    592             struct scsipi_sense *ss = (void *)&acb->cmd;
    593 
    594 #ifdef DEBUG
    595             if ( report_sense )
    596                 printf("sbic_scsidone: autosense %02x targ %d lun %d",
    597                         acb->cmd.opcode, slp->scsipi_scsi.target,
    598 						slp->scsipi_scsi.lun);
    599 #endif
    600 
    601             bzero(ss, sizeof(*ss));
    602 
    603             ss->opcode          = REQUEST_SENSE;
    604             ss->byte2           = slp->scsipi_scsi.lun << 5;
    605             ss->length          = sizeof(struct scsipi_sense_data);
    606 
    607             acb->clen           = sizeof(*ss);
    608             acb->sc_kv.dc_addr  = (char *)&xs->sense.scsi_sense;
    609             acb->sc_kv.dc_count = sizeof(struct scsipi_sense_data);
    610             acb->pa_addr        = (char *)kvtop(&xs->sense.scsi_sense); /* XXX check */
    611             acb->flags          = ACB_ACTIVE | ACB_CHKSENSE | ACB_DATAIN;
    612 
    613             TAILQ_INSERT_HEAD(&dev->ready_list, acb, chain);
    614 
    615             dev->sc_tinfo[slp->scsipi_scsi.target].lubusy &=
    616 				~(1 << slp->scsipi_scsi.lun);
    617             dev->sc_tinfo[slp->scsipi_scsi.target].senses++;
    618 
    619             if ( dev->sc_nexus == acb ) {
    620                 dev->sc_nexus = NULL;
    621                 dev->sc_xs = NULL;
    622                 sbic_sched(dev);
    623             }
    624             return;
    625         }
    626     }
    627 
    628     if ( xs->error == XS_NOERROR && (acb->flags & ACB_CHKSENSE) != 0 ) {
    629 
    630         xs->error = XS_SENSE;
    631 
    632 #ifdef DEBUG
    633         if (report_sense)
    634             printf(" => %02x %02x\n", xs->sense.scsi_sense.flags,
    635 			xs->sense.scsi_sense.extra_bytes[3]);
    636 #endif
    637 
    638     } else {
    639         xs->resid = 0;      /* XXXX */
    640     }
    641 
    642     xs->flags |= ITSDONE;
    643 
    644     /*
    645      * Remove the ACB from whatever queue it's on.  We have to do a bit of
    646      * a hack to figure out which queue it's on.  Note that it is *not*
    647      * necessary to cdr down the ready queue, but we must cdr down the
    648      * nexus queue and see if it's there, so we can mark the unit as no
    649      * longer busy.  This code is sickening, but it works.
    650      */
    651     if ( acb == dev->sc_nexus ) {
    652 
    653         dev->sc_nexus = NULL;
    654         dev->sc_xs    = NULL;
    655 
    656         dev->sc_tinfo[slp->scsipi_scsi.target].lubusy &=
    657 			~(1 << slp->scsipi_scsi.lun);
    658 
    659         if ( dev->ready_list.tqh_first )
    660             dosched = 1;    /* start next command */
    661 
    662     } else
    663     if ( dev->ready_list.tqh_last == &acb->chain.tqe_next ) {
    664 
    665         TAILQ_REMOVE(&dev->ready_list, acb, chain);
    666 
    667     } else {
    668 
    669         struct sbic_acb *a;
    670 
    671         for (a = dev->nexus_list.tqh_first; a; a = a->chain.tqe_next) {
    672             if ( a == acb ) {
    673                 TAILQ_REMOVE(&dev->nexus_list, acb, chain);
    674                 dev->sc_tinfo[slp->scsipi_scsi.target].lubusy &=
    675 					~(1 << slp->scsipi_scsi.lun);
    676                 break;
    677             }
    678         }
    679 
    680         if ( a )
    681             ;
    682         else if ( acb->chain.tqe_next ) {
    683             TAILQ_REMOVE(&dev->ready_list, acb, chain);
    684         } else {
    685             printf("%s: can't find matching acb\n", dev->sc_dev.dv_xname);
    686 #ifdef DDB
    687             Debugger();
    688 #endif
    689         }
    690     }
    691 
    692     /*
    693      * Put it on the free list.
    694      */
    695     acb->flags = ACB_FREE;
    696     TAILQ_INSERT_HEAD(&dev->free_list, acb, chain);
    697 
    698     dev->sc_tinfo[slp->scsipi_scsi.target].cmds++;
    699 
    700     scsipi_done(xs);
    701 
    702     if ( dosched )
    703         sbic_sched(dev);
    704 }
    705 
    706 int
    707 sbicdmaok(dev, xs)
    708     struct sbic_softc   *dev;
    709     struct scsipi_xfer    *xs;
    710 {
    711     if ( sbic_no_dma || xs->datalen & 0x03 || (int)xs->data & 0x03)
    712         return(0);
    713 
    714     /*
    715      * controller supports dma to any addresses?
    716      */
    717     if ( (dev->sc_flags & SBICF_BADDMA) == 0 )
    718         return(1);
    719 
    720     /*
    721      * this address is ok for dma?
    722      */
    723     if ( sbiccheckdmap(xs->data, xs->datalen, dev->sc_dmamask) == 0 )
    724         return(1);
    725 
    726     return(0);
    727 }
    728 
    729 int
    730 sbicwait(regs, until, timeo, line)
    731     sbic_regmap_p   regs;
    732     u_char          until;
    733     int             timeo;
    734     int             line;
    735 {
    736     u_char  val;
    737 
    738     if ( timeo == 0 )
    739         timeo = 1000000;    /* some large value.. */
    740 
    741     GET_SBIC_asr(regs, val);
    742 
    743     while ( (val & until) == 0 ) {
    744 
    745         if ( timeo-- == 0 ) {
    746             int csr;
    747             GET_SBIC_csr(regs, csr);
    748             printf("sbicwait TIMEO @%d with asr=x%x csr=x%x\n", line, val, csr);
    749 #if defined(DDB) && defined(DEBUG)
    750             Debugger();
    751 #endif
    752             return(val); /* Maybe I should abort */
    753             break;
    754         }
    755 
    756         DELAY(1);
    757         GET_SBIC_asr(regs, val);
    758     }
    759 
    760     return(val);
    761 }
    762 
    763 int
    764 sbicabort(dev, where)
    765     struct sbic_softc   *dev;
    766     char                *where;
    767 {
    768     sbic_regmap_p   regs = dev->sc_sbicp;
    769     u_char          csr,
    770                     asr;
    771 
    772     GET_SBIC_asr(regs, asr);
    773     GET_SBIC_csr(regs, csr);
    774 
    775     printf ("%s: abort %s: csr = 0x%02x, asr = 0x%02x\n",
    776             dev->sc_dev.dv_xname, where, csr, asr);
    777 
    778     /*
    779      * Clean up chip itself
    780      */
    781     if ( dev->sc_flags & SBICF_SELECTED ) {
    782 
    783         while ( asr & SBIC_ASR_DBR ) {
    784             /*
    785              * sbic is jammed w/data. need to clear it
    786              * But we don't know what direction it needs to go
    787              */
    788             GET_SBIC_data(regs, asr);
    789             printf("%s: abort %s: clearing data buffer 0x%02x\n",
    790                    dev->sc_dev.dv_xname, where, asr);
    791             GET_SBIC_asr(regs, asr);
    792             if ( asr & SBIC_ASR_DBR ) /* Not the read direction, then */
    793                 SET_SBIC_data(regs, asr);
    794             GET_SBIC_asr(regs, asr);
    795         }
    796 
    797         WAIT_CIP(regs);
    798 
    799         printf("%s: sbicabort - sending ABORT command\n", dev->sc_dev.dv_xname);
    800         SET_SBIC_cmd(regs, SBIC_CMD_ABORT);
    801         WAIT_CIP(regs);
    802 
    803         GET_SBIC_asr(regs, asr);
    804 
    805         if ( asr & (SBIC_ASR_BSY|SBIC_ASR_LCI) ) {
    806             /*
    807              * ok, get more drastic..
    808              */
    809             printf("%s: sbicabort - asr %x, trying to reset\n",
    810                     dev->sc_dev.dv_xname, asr);
    811             sbicreset(dev);
    812             dev->sc_flags &= ~SBICF_SELECTED;
    813             return SBIC_STATE_ERROR;
    814         }
    815 
    816         printf("%s: sbicabort - sending DISC command\n", dev->sc_dev.dv_xname);
    817         SET_SBIC_cmd(regs, SBIC_CMD_DISC);
    818 
    819         do {
    820             SBIC_WAIT (regs, SBIC_ASR_INT, 0);
    821             GET_SBIC_asr(regs, asr);
    822             GET_SBIC_csr (regs, csr);
    823             QPRINTF(("csr: 0x%02x, asr: 0x%02x\n", csr, asr));
    824         } while ( (csr != SBIC_CSR_DISC) && (csr != SBIC_CSR_DISC_1) &&
    825                   (csr != SBIC_CSR_CMD_INVALID) );
    826 
    827         /*
    828          * lets just hope it worked..
    829          */
    830         dev->sc_flags &= ~SBICF_SELECTED;
    831     }
    832 
    833     return SBIC_STATE_ERROR;
    834 }
    835 
    836 
    837 /*
    838  * Initialize driver-private structures
    839  */
    840 void
    841 sbicinit(dev)
    842     struct sbic_softc *dev;
    843 {
    844     u_int   i;
    845 
    846     extern u_long   scsi_nosync;
    847     extern int      shift_nosync;
    848 
    849     if ( (dev->sc_flags & SBICF_ALIVE) == 0 ) {
    850 
    851         struct sbic_acb *acb;
    852 
    853         TAILQ_INIT(&dev->ready_list);
    854         TAILQ_INIT(&dev->nexus_list);
    855         TAILQ_INIT(&dev->free_list);
    856 
    857         dev->sc_nexus = NULL;
    858         dev->sc_xs    = NULL;
    859 
    860         acb = dev->sc_acb;
    861         bzero(acb, sizeof(dev->sc_acb));
    862 
    863         for (i = 0; i < sizeof(dev->sc_acb) / sizeof(*acb); i++) {
    864             TAILQ_INSERT_TAIL(&dev->free_list, acb, chain);
    865             acb++;
    866         }
    867 
    868         bzero(dev->sc_tinfo, sizeof(dev->sc_tinfo));
    869 
    870 #ifdef DEBUG
    871         /*
    872          * make sure timeout is really not needed
    873          */
    874         timeout((void *)sbictimeout, dev, 30 * hz);
    875 #endif
    876 
    877     } else
    878         panic("sbic: reinitializing driver!");
    879 
    880     dev->sc_flags |=  SBICF_ALIVE;
    881     dev->sc_flags &= ~SBICF_SELECTED;
    882 
    883     /*
    884      * initialize inhibit array
    885      */
    886     if ( scsi_nosync ) {
    887 
    888         u_int inhibit_sync = (scsi_nosync >> shift_nosync) & 0xff;
    889 
    890         shift_nosync += 8;
    891 
    892 #ifdef DEBUG
    893         if ( inhibit_sync )
    894             printf("%s: Inhibiting synchronous transfer %02x\n",
    895                         dev->sc_dev.dv_xname, inhibit_sync);
    896 #endif
    897         for (i = 0; i < 8; ++i) {
    898             if ( inhibit_sync & (1 << i) )
    899                 sbic_inhibit_sync[i] = 1;
    900         }
    901     }
    902 
    903     sbicreset(dev);
    904 }
    905 
    906 void
    907 sbicreset(dev)
    908     struct sbic_softc *dev;
    909 {
    910     sbic_regmap_p   regs = dev->sc_sbicp;
    911     u_int           my_id,
    912                     s;
    913     u_char          csr;
    914 
    915     s = splbio();
    916 
    917     my_id = dev->sc_link.scsipi_scsi.adapter_target & SBIC_ID_MASK;
    918 
    919     if (dev->sc_clkfreq < 110)
    920         my_id |= SBIC_ID_FS_8_10;
    921     else if (dev->sc_clkfreq < 160)
    922         my_id |= SBIC_ID_FS_12_15;
    923     else if (dev->sc_clkfreq < 210)
    924         my_id |= SBIC_ID_FS_16_20;
    925 
    926     SET_SBIC_myid(regs, my_id);
    927 
    928     /*
    929      * Reset the chip
    930      */
    931     SET_SBIC_cmd(regs, SBIC_CMD_RESET);
    932     DELAY(25);
    933 
    934     SBIC_WAIT(regs, SBIC_ASR_INT, 0);
    935     GET_SBIC_csr(regs, csr);       /* clears interrupt also */
    936 
    937     /*
    938      * Set up various chip parameters
    939      */
    940     SET_SBIC_control(regs, SBIC_CTL_EDI | SBIC_CTL_IDI);
    941 
    942     /*
    943      * don't allow Selection (SBIC_RID_ES)
    944      * until we can handle target mode!!
    945      */
    946     SET_SBIC_rselid(regs, SBIC_RID_ER);
    947 
    948     /*
    949      * Asynchronous for now
    950      */
    951     SET_SBIC_syn(regs, 0);
    952 
    953     /*
    954      * Anything else was zeroed by reset
    955      */
    956     splx(s);
    957 
    958     dev->sc_flags &= ~SBICF_SELECTED;
    959 }
    960 
    961 void
    962 sbicerror(dev, csr)
    963     struct sbic_softc   *dev;
    964     u_char              csr;
    965 {
    966     struct scsipi_xfer    *xs  = dev->sc_xs;
    967 
    968 #ifdef DIAGNOSTIC
    969     if ( xs == NULL )
    970         panic("sbicerror: dev->sc_xs == NULL");
    971 #endif
    972 
    973     if ( xs->flags & SCSI_SILENT )
    974         return;
    975 
    976     printf("%s: csr == 0x%02x\n", dev->sc_dev.dv_xname, csr);
    977 }
    978 
    979 /*
    980  * select the bus, return when selected or error.
    981  *
    982  * Returns the current CSR following selection and optionally MSG out phase.
    983  * i.e. the returned CSR *should* indicate CMD phase...
    984  * If the return value is 0, some error happened.
    985  */
    986 u_char
    987 sbicselectbus(dev)
    988     struct sbic_softc   *dev;
    989 {
    990     sbic_regmap_p   regs   = dev->sc_sbicp;
    991     u_char          target = dev->target,
    992                     lun    = dev->lun,
    993                     asr,
    994                     csr,
    995                     id;
    996 
    997     /*
    998      * if we're already selected, return (XXXX panic maybe?)
    999      */
   1000     if ( dev->sc_flags & SBICF_SELECTED )
   1001         return(0);
   1002 
   1003     QPRINTF(("sbicselectbus %d: ", target));
   1004 
   1005     /*
   1006      * issue select
   1007      */
   1008     SET_SBIC_selid(regs, target);
   1009     SET_SBIC_timeo(regs, SBIC_TIMEOUT(250, dev->sc_clkfreq));
   1010 
   1011     GET_SBIC_asr(regs, asr);
   1012 
   1013     if ( asr & (SBIC_ASR_INT|SBIC_ASR_BSY) ) {
   1014         /*
   1015          * This means we got ourselves reselected upon
   1016          */
   1017         QPRINTF(("WD busy (reselect?)\n"));
   1018         return 0;
   1019     }
   1020 
   1021     SET_SBIC_cmd(regs, SBIC_CMD_SEL_ATN);
   1022 
   1023     /*
   1024      * wait for select (merged from seperate function may need
   1025      * cleanup)
   1026      */
   1027     WAIT_CIP(regs);
   1028 
   1029     do {
   1030 
   1031         asr = SBIC_WAIT(regs, SBIC_ASR_INT | SBIC_ASR_LCI, 0);
   1032 
   1033         if ( asr & SBIC_ASR_LCI ) {
   1034             QPRINTF(("late LCI: asr %02x\n", asr));
   1035             return 0;
   1036         }
   1037 
   1038         /*
   1039          * Clear interrupt
   1040          */
   1041         GET_SBIC_csr (regs, csr);
   1042 
   1043         QPRINTF(("%02x ", csr));
   1044 
   1045         /*
   1046          * Reselected from under our feet?
   1047          */
   1048         if ( csr == SBIC_CSR_RSLT_NI || csr == SBIC_CSR_RSLT_IFY ) {
   1049             QPRINTF(("got reselected, asr %02x\n", asr));
   1050             /*
   1051              * We need to handle this now so we don't lock up later
   1052              */
   1053             sbicnextstate(dev, csr, asr);
   1054 
   1055             return 0;
   1056         }
   1057 
   1058         /*
   1059          * Whoops!
   1060          */
   1061         if ( csr == SBIC_CSR_SLT || csr == SBIC_CSR_SLT_ATN ) {
   1062             panic("sbicselectbus: target issued select!");
   1063             return 0;
   1064         }
   1065 
   1066     } while (csr != (SBIC_CSR_MIS_2 | MESG_OUT_PHASE) &&
   1067              csr != (SBIC_CSR_MIS_2 | CMD_PHASE) &&
   1068              csr != SBIC_CSR_SEL_TIMEO);
   1069 
   1070     /*
   1071      * Anyone at home?
   1072      */
   1073     if ( csr == SBIC_CSR_SEL_TIMEO ) {
   1074         dev->sc_xs->error = XS_SELTIMEOUT;
   1075         QPRINTF(("Selection Timeout\n"));
   1076         return 0;
   1077     }
   1078 
   1079     QPRINTF(("Selection Complete\n"));
   1080 
   1081     /*
   1082      * Assume we're now selected
   1083      */
   1084     GET_SBIC_selid(regs, id);
   1085     dev->target    = id;
   1086     dev->lun       = lun;
   1087     dev->sc_flags |= SBICF_SELECTED;
   1088 
   1089     /*
   1090      * Enable (or not) reselection
   1091      * XXXSCW This is probably not necessary since we don't use use the
   1092      * Select-and-Xfer-with-ATN command to initiate a selection...
   1093      */
   1094     if ( !sbic_enable_reselect && dev->nexus_list.tqh_first == NULL)
   1095         SET_SBIC_rselid (regs, 0);
   1096     else
   1097         SET_SBIC_rselid (regs, SBIC_RID_ER);
   1098 
   1099     /*
   1100      * We only really need to do anything when the target goes to MSG out
   1101      * If the device ignored ATN, it's probably old and brain-dead,
   1102      * but we'll try to support it anyhow.
   1103      * If it doesn't support message out, it definately doesn't
   1104      * support synchronous transfers, so no point in even asking...
   1105      */
   1106     if ( csr == (SBIC_CSR_MIS_2 | MESG_OUT_PHASE) ) {
   1107         /*
   1108          * Send identify message (SCSI-2 requires an identify msg)
   1109          */
   1110         if ( sbic_inhibit_sync[id] && dev->sc_sync[id].state == SYNC_START ) {
   1111             /*
   1112              * Handle drives that don't want to be asked
   1113              * whether to go sync at all.
   1114              */
   1115             dev->sc_sync[id].offset = 0;
   1116             dev->sc_sync[id].period = sbic_min_period;
   1117             dev->sc_sync[id].state  = SYNC_DONE;
   1118         }
   1119 
   1120         /*
   1121          * Do we need to negotiate Synchronous Xfers for this target?
   1122          */
   1123         if ( dev->sc_sync[id].state != SYNC_START ) {
   1124             /*
   1125              * Nope, we've already negotiated.
   1126              * Now see if we should allow the target to disconnect/reselect...
   1127              */
   1128             if ( dev->sc_xs->flags & SCSI_POLL || dev->sc_flags & SBICF_ICMD ||
   1129                                                   !sbic_enable_reselect )
   1130                 SEND_BYTE (regs, MSG_IDENTIFY | lun);
   1131             else
   1132                 SEND_BYTE (regs, MSG_IDENTIFY_DR | lun);
   1133 
   1134         } else {
   1135             /*
   1136              * try to initiate a sync transfer.
   1137              * So compose the sync message we're going
   1138              * to send to the target
   1139              */
   1140 #ifdef DEBUG
   1141             if ( sync_debug )
   1142                 printf("\nSending sync request to target %d ... ", id);
   1143 #endif
   1144             /*
   1145              * setup scsi message sync message request
   1146              */
   1147             dev->sc_msg[0] = MSG_IDENTIFY | lun;
   1148             dev->sc_msg[1] = MSG_EXT_MESSAGE;
   1149             dev->sc_msg[2] = 3;
   1150             dev->sc_msg[3] = MSG_SYNC_REQ;
   1151             dev->sc_msg[4] = sbictoscsiperiod(dev, sbic_min_period);
   1152             dev->sc_msg[5] = sbic_max_offset;
   1153 
   1154             sbicxfout(regs, 6, dev->sc_msg);
   1155 
   1156             dev->sc_sync[id].state = SYNC_SENT;
   1157 #ifdef DEBUG
   1158             if ( sync_debug )
   1159                 printf ("sent\n");
   1160 #endif
   1161         }
   1162 
   1163         /*
   1164          * There's one interrupt still to come: the change to CMD phase...
   1165          */
   1166         SBIC_WAIT(regs, SBIC_ASR_INT , 0);
   1167         GET_SBIC_csr(regs, csr);
   1168     }
   1169 
   1170     /*
   1171      * set sync or async
   1172      */
   1173     if ( dev->sc_sync[target].state == SYNC_DONE ) {
   1174 #ifdef  DEBUG
   1175         if ( sync_debug )
   1176             printf("select(%d): sync reg = 0x%02x\n", target,
   1177                             SBIC_SYN(dev->sc_sync[target].offset,
   1178                                      dev->sc_sync[target].period));
   1179 #endif
   1180         SET_SBIC_syn(regs, SBIC_SYN(dev->sc_sync[target].offset,
   1181                                     dev->sc_sync[target].period));
   1182     } else {
   1183 #ifdef  DEBUG
   1184         if ( sync_debug )
   1185             printf("select(%d): sync reg = 0x%02x\n", target,
   1186                             SBIC_SYN(0,sbic_min_period));
   1187 #endif
   1188         SET_SBIC_syn(regs, SBIC_SYN(0, sbic_min_period));
   1189     }
   1190 
   1191     return csr;
   1192 }
   1193 
   1194 /*
   1195  * Information Transfer *to* a Scsi Target.
   1196  *
   1197  * Note: Don't expect there to be an interrupt immediately after all
   1198  * the data is transferred out. The WD spec sheet says that the Transfer-
   1199  * Info command for non-MSG_IN phases only completes when the target
   1200  * next asserts 'REQ'. That is, when the SCSI bus changes to a new state.
   1201  *
   1202  * This can have a nasty effect on commands which take a relatively long
   1203  * time to complete, for example a START/STOP unit command may remain in
   1204  * CMD phase until the disk has spun up. Only then will the target change
   1205  * to STATUS phase. This is really only a problem for immediate commands
   1206  * since we don't allow disconnection for them (yet).
   1207  */
   1208 int
   1209 sbicxfout(regs, len, bp)
   1210     sbic_regmap_p   regs;
   1211     int             len;
   1212     void            *bp;
   1213 {
   1214     int     wait = sbic_data_wait;
   1215     u_char  asr,
   1216             *buf = bp;
   1217 
   1218     QPRINTF(("sbicxfout {%d} %02x %02x %02x %02x %02x "
   1219         "%02x %02x %02x %02x %02x\n", len, buf[0], buf[1], buf[2],
   1220         buf[3], buf[4], buf[5], buf[6], buf[7], buf[8], buf[9]));
   1221 
   1222     /*
   1223      * sigh.. WD-PROTO strikes again.. sending the command in one go
   1224      * causes the chip to lock up if talking to certain (misbehaving?)
   1225      * targets. Anyway, this procedure should work for all targets, but
   1226      * it's slightly slower due to the overhead
   1227      */
   1228     WAIT_CIP (regs);
   1229 
   1230     SBIC_TC_PUT (regs, 0);
   1231     SET_SBIC_control(regs, SBIC_CTL_EDI | SBIC_CTL_IDI);
   1232     SBIC_TC_PUT (regs, (unsigned)len);
   1233     SET_SBIC_cmd (regs, SBIC_CMD_XFER_INFO);
   1234 
   1235     /*
   1236      * Loop for each byte transferred
   1237      */
   1238     do {
   1239 
   1240         GET_SBIC_asr (regs, asr);
   1241 
   1242         if ( asr & SBIC_ASR_DBR ) {
   1243             if ( len ) {
   1244                 SET_SBIC_data (regs, *buf);
   1245                 buf++;
   1246                 len--;
   1247             } else {
   1248                 SET_SBIC_data (regs, 0);
   1249             }
   1250             wait = sbic_data_wait;
   1251         }
   1252 
   1253     } while ( len && (asr & SBIC_ASR_INT) == 0 && wait-- > 0 );
   1254 
   1255 #ifdef  DEBUG
   1256     QPRINTF(("sbicxfout done: %d bytes remaining (wait:%d)\n", len, wait));
   1257 #endif
   1258 
   1259     /*
   1260      * Normally, an interrupt will be pending when this routing returns.
   1261      */
   1262     return(len);
   1263 }
   1264 
   1265 /*
   1266  * Information Transfer *from* a Scsi Target
   1267  * returns # bytes left to read
   1268  */
   1269 int
   1270 sbicxfin(regs, len, bp)
   1271     sbic_regmap_p   regs;
   1272     int             len;
   1273     void            *bp;
   1274 {
   1275     int     wait = sbic_data_wait;
   1276     u_char  *buf = bp;
   1277     u_char  asr;
   1278 #ifdef  DEBUG
   1279     u_char  *obp = bp;
   1280 #endif
   1281 
   1282     WAIT_CIP (regs);
   1283 
   1284     SET_SBIC_control(regs, SBIC_CTL_EDI | SBIC_CTL_IDI);
   1285     SBIC_TC_PUT (regs, (unsigned)len);
   1286     SET_SBIC_cmd (regs, SBIC_CMD_XFER_INFO);
   1287 
   1288     /*
   1289      * Loop for each byte transferred
   1290      */
   1291     do {
   1292 
   1293         GET_SBIC_asr (regs, asr);
   1294 
   1295         if ( asr & SBIC_ASR_DBR ) {
   1296             if ( len ) {
   1297                 GET_SBIC_data (regs, *buf);
   1298                 buf++;
   1299                 len--;
   1300             } else {
   1301                 u_char foo;
   1302                 GET_SBIC_data (regs, foo);
   1303             }
   1304             wait = sbic_data_wait;
   1305         }
   1306 
   1307     } while ( (asr & SBIC_ASR_INT) == 0 && wait-- > 0 );
   1308 
   1309     QPRINTF(("sbicxfin {%d} %02x %02x %02x %02x %02x %02x "
   1310         "%02x %02x %02x %02x\n", len, obp[0], obp[1], obp[2],
   1311         obp[3], obp[4], obp[5], obp[6], obp[7], obp[8], obp[9]));
   1312 
   1313     SBIC_TC_PUT (regs, 0);
   1314 
   1315     /*
   1316      * this leaves with one csr to be read
   1317      */
   1318     return len;
   1319 }
   1320 
   1321 /*
   1322  * SCSI 'immediate' command:  issue a command to some SCSI device
   1323  * and get back an 'immediate' response (i.e., do programmed xfer
   1324  * to get the response data).  'cbuf' is a buffer containing a scsi
   1325  * command of length clen bytes.  'buf' is a buffer of length 'len'
   1326  * bytes for data.  The transfer direction is determined by the device
   1327  * (i.e., by the scsi bus data xfer phase).  If 'len' is zero, the
   1328  * command must supply no data.
   1329  *
   1330  * Note that although this routine looks like it can handle disconnect/
   1331  * reselect, the fact is that it can't. There is still some work to be
   1332  * done to clean this lot up.
   1333  */
   1334 int
   1335 sbicicmd(dev, cbuf, clen, buf, len)
   1336     struct sbic_softc   *dev;
   1337     void                *cbuf,
   1338                         *buf;
   1339     int                 clen,
   1340                         len;
   1341 {
   1342     sbic_regmap_p   regs = dev->sc_sbicp;
   1343     struct sbic_acb *acb = dev->sc_nexus;
   1344     u_char          csr,
   1345                     asr;
   1346     int             still_busy = SBIC_STATE_RUNNING;
   1347 #ifdef  DEBUG
   1348     int             counter = 0;
   1349 #endif
   1350 
   1351     /*
   1352      * Make sure pointers are OK
   1353      */
   1354     dev->sc_last = dev->sc_cur = &acb->sc_pa;
   1355     dev->sc_tcnt = acb->sc_tcnt = 0;
   1356 
   1357     acb->sc_dmacmd      = 0;
   1358     acb->sc_pa.dc_count = 0; /* No DMA */
   1359     acb->sc_kv.dc_addr  = buf;
   1360     acb->sc_kv.dc_count = len;
   1361 
   1362 #ifdef  DEBUG
   1363     if ( data_pointer_debug > 1 )
   1364         printf("sbicicmd(%d,%d):%d\n", dev->target, dev->lun, acb->sc_kv.dc_count);
   1365 #endif
   1366 
   1367     /*
   1368      * set the sbic into non-DMA mode
   1369      */
   1370     SET_SBIC_control(regs, SBIC_CTL_EDI | SBIC_CTL_IDI);
   1371 
   1372     dev->sc_stat[0] = 0xff;
   1373     dev->sc_msg[0]  = 0xff;
   1374 
   1375     /*
   1376      * We're stealing the SCSI bus
   1377      */
   1378     dev->sc_flags |= SBICF_ICMD;
   1379 
   1380     do {
   1381         GET_SBIC_asr (regs, asr);
   1382 
   1383         /*
   1384          * select the SCSI bus (it's an error if bus isn't free)
   1385          */
   1386         if ( (dev->sc_flags & SBICF_SELECTED) == 0 &&
   1387              still_busy != SBIC_STATE_DISCONNECT ) {
   1388             if ( (csr = sbicselectbus(dev)) == 0 ) {
   1389                 dev->sc_flags &= ~SBICF_ICMD;
   1390                 return(-1);
   1391             }
   1392         } else
   1393         if ( (asr & (SBIC_ASR_BSY | SBIC_ASR_INT)) == SBIC_ASR_INT )
   1394             GET_SBIC_csr(regs, csr);
   1395         else
   1396             csr = 0;
   1397 
   1398         if ( csr ) {
   1399 
   1400             QPRINTF((">ASR:0x%02x CSR:0x%02x< ", asr, csr));
   1401 
   1402             switch ( csr ) {
   1403 
   1404               case SBIC_CSR_S_XFERRED:
   1405               case SBIC_CSR_DISC:
   1406               case SBIC_CSR_DISC_1:
   1407                 {
   1408                     u_char  phase;
   1409 
   1410                     dev->sc_flags &= ~SBICF_SELECTED;
   1411                     GET_SBIC_cmd_phase (regs, phase);
   1412 
   1413                     if ( phase == 0x60 ) {
   1414                         GET_SBIC_tlun (regs, dev->sc_stat[0]);
   1415                         still_busy = SBIC_STATE_DONE; /* done */
   1416                     } else {
   1417 #ifdef DEBUG
   1418                         if ( reselect_debug > 1 )
   1419                             printf("sbicicmd: handling disconnect\n");
   1420 #endif
   1421                         still_busy = SBIC_STATE_DISCONNECT;
   1422                     }
   1423                 }
   1424                 break;
   1425 
   1426               case SBIC_CSR_XFERRED | CMD_PHASE:
   1427               case SBIC_CSR_MIS     | CMD_PHASE:
   1428               case SBIC_CSR_MIS_1   | CMD_PHASE:
   1429               case SBIC_CSR_MIS_2   | CMD_PHASE:
   1430                 {
   1431                     if ( sbicxfout(regs, clen, cbuf) )
   1432                         still_busy = sbicabort(dev, "icmd sending cmd");
   1433                 }
   1434                 break;
   1435 
   1436               case SBIC_CSR_XFERRED | STATUS_PHASE:
   1437               case SBIC_CSR_MIS     | STATUS_PHASE:
   1438               case SBIC_CSR_MIS_1   | STATUS_PHASE:
   1439               case SBIC_CSR_MIS_2   | STATUS_PHASE:
   1440                 {
   1441                     /*
   1442                      * The sbic does the status/cmd-complete reading ok,
   1443                      * so do this with its hi-level commands.
   1444                      */
   1445 #ifdef DEBUG
   1446                     if ( sbic_debug )
   1447                         printf("SBICICMD status phase (bsy=%d)\n", still_busy);
   1448 #endif
   1449                     SET_SBIC_cmd_phase(regs, 0x46);
   1450                     SET_SBIC_cmd(regs, SBIC_CMD_SEL_ATN_XFER);
   1451                 }
   1452                 break;
   1453 
   1454               default:
   1455                 {
   1456                     still_busy = sbicnextstate(dev, csr, asr);
   1457                 }
   1458                 break;
   1459             }
   1460 
   1461             /*
   1462              * make sure the last command was taken,
   1463              * ie. we're not hunting after an ignored command..
   1464              */
   1465             GET_SBIC_asr(regs, asr);
   1466 
   1467             /*
   1468              * tapes may take a loooong time..
   1469              */
   1470             while (asr & SBIC_ASR_BSY ) {
   1471 
   1472                 if ( asr & SBIC_ASR_DBR ) {
   1473                     int     i;
   1474 
   1475                     printf("sbicicmd: Waiting while sbic is jammed, CSR:%02x,ASR:%02x\n", csr,asr);
   1476 #ifdef DDB
   1477                     Debugger();
   1478 #endif
   1479                     /*
   1480                      * SBIC is jammed
   1481                      * DUNNO which direction
   1482                      * Try old direction
   1483                      */
   1484                     GET_SBIC_data(regs, i);
   1485                     GET_SBIC_asr(regs, asr);
   1486 
   1487                     if ( asr & SBIC_ASR_DBR ) /* Wants us to write */
   1488                         SET_SBIC_data(regs, i);
   1489                 }
   1490 
   1491                 GET_SBIC_asr(regs, asr);
   1492             }
   1493         }
   1494 
   1495         /*
   1496          * wait for last command to complete
   1497          */
   1498         if ( asr & SBIC_ASR_LCI ) {
   1499             printf("sbicicmd: last command ignored\n");
   1500         }
   1501         else
   1502         if ( still_busy >= SBIC_STATE_RUNNING ) /* Bsy */
   1503             SBIC_WAIT (regs, SBIC_ASR_INT, sbic_cmd_wait);
   1504 
   1505         /*
   1506          * do it again
   1507          */
   1508     } while ( still_busy >= SBIC_STATE_RUNNING && dev->sc_stat[0] == 0xff );
   1509 
   1510     /*
   1511      * Sometimes we need to do an extra read of the CSR
   1512      */
   1513     GET_SBIC_csr(regs, csr);
   1514 
   1515 #ifdef DEBUG
   1516     if ( data_pointer_debug > 1 )
   1517         printf("sbicicmd done(%d,%d):%d =%d=\n", dev->target, dev->lun,
   1518                                                  acb->sc_kv.dc_count,
   1519                                                  dev->sc_stat[0]);
   1520 #endif
   1521 
   1522     dev->sc_flags &= ~SBICF_ICMD;
   1523 
   1524     return(dev->sc_stat[0]);
   1525 }
   1526 
   1527 /*
   1528  * Finish SCSI xfer command:  After the completion interrupt from
   1529  * a read/write operation, sequence through the final phases in
   1530  * programmed i/o.  This routine is a lot like sbicicmd except we
   1531  * skip (and don't allow) the select, cmd out and data in/out phases.
   1532  */
   1533 void
   1534 sbicxfdone(dev)
   1535     struct sbic_softc   *dev;
   1536 {
   1537     sbic_regmap_p   regs = dev->sc_sbicp;
   1538     u_char          phase,
   1539                     csr;
   1540     int             s;
   1541 
   1542     QPRINTF(("{"));
   1543     s = splbio();
   1544 
   1545     /*
   1546      * have the sbic complete on its own
   1547      */
   1548     SBIC_TC_PUT(regs, 0);
   1549     SET_SBIC_cmd_phase(regs, 0x46);
   1550     SET_SBIC_cmd(regs, SBIC_CMD_SEL_ATN_XFER);
   1551 
   1552     do {
   1553 
   1554         SBIC_WAIT (regs, SBIC_ASR_INT, 0);
   1555         GET_SBIC_csr (regs, csr);
   1556         QPRINTF(("%02x:", csr));
   1557 
   1558     } while ( (csr != SBIC_CSR_DISC) && (csr != SBIC_CSR_DISC_1) &&
   1559               (csr != SBIC_CSR_S_XFERRED));
   1560 
   1561     dev->sc_flags &= ~SBICF_SELECTED;
   1562 
   1563     GET_SBIC_cmd_phase (regs, phase);
   1564     QPRINTF(("}%02x", phase));
   1565 
   1566     if ( phase == 0x60 )
   1567         GET_SBIC_tlun(regs, dev->sc_stat[0]);
   1568     else
   1569         sbicerror(dev, csr);
   1570 
   1571     QPRINTF(("=STS:%02x=\n", dev->sc_stat[0]));
   1572 
   1573     splx(s);
   1574 }
   1575 
   1576 /*
   1577  * No DMA chains
   1578  */
   1579 int
   1580 sbicgo(dev, xs)
   1581     struct sbic_softc   *dev;
   1582     struct scsipi_xfer    *xs;
   1583 {
   1584     struct sbic_acb *acb = dev->sc_nexus;
   1585     sbic_regmap_p   regs = dev->sc_sbicp;
   1586     int             i,
   1587                     dmaflags,
   1588                     count,
   1589                     usedma;
   1590     u_char          csr,
   1591                     asr,
   1592                     *addr;
   1593 
   1594     dev->target = xs->sc_link->scsipi_scsi.target;
   1595     dev->lun    = xs->sc_link->scsipi_scsi.lun;
   1596 
   1597     usedma = sbicdmaok(dev, xs);
   1598 
   1599 #ifdef DEBUG
   1600     if ( data_pointer_debug > 1 )
   1601         printf("sbicgo(%d,%d): usedma=%d\n", dev->target, dev->lun, usedma);
   1602 #endif
   1603 
   1604     /*
   1605      * select the SCSI bus (it's an error if bus isn't free)
   1606      */
   1607     if ( (csr = sbicselectbus(dev)) == 0 )
   1608         return(0); /* Not done: needs to be rescheduled */
   1609 
   1610     dev->sc_stat[0] = 0xff;
   1611 
   1612     /*
   1613      * Calculate DMA chains now
   1614      */
   1615     if ( acb->flags & ACB_DATAIN )
   1616         dmaflags = DMAGO_READ;
   1617     else
   1618         dmaflags = 0;
   1619 
   1620     addr  = acb->sc_kv.dc_addr;
   1621     count = acb->sc_kv.dc_count;
   1622 
   1623     if ( count && ((char *)kvtop(addr) != acb->sc_pa.dc_addr) ) {
   1624         printf("sbic: DMA buffer mapping changed %x->%x\n",
   1625                 acb->sc_pa.dc_addr, kvtop(addr));
   1626 #ifdef DDB
   1627         Debugger();
   1628 #endif
   1629     }
   1630 
   1631 #ifdef DEBUG
   1632     ++sbicdma_ops;          /* count total DMA operations */
   1633 #endif
   1634 
   1635     /*
   1636      * Allocate the DMA chain
   1637      * Mark end of segment...
   1638      */
   1639     acb->sc_tcnt        = dev->sc_tcnt = 0;
   1640     acb->sc_pa.dc_count = 0;
   1641 
   1642     sbic_load_ptrs(dev);
   1643 
   1644     /*
   1645      * Enable interrupts but don't do any DMA
   1646      * enintr() also enables interrupts for the sbic
   1647      */
   1648     dev->sc_enintr(dev);
   1649 
   1650     if ( usedma ) {
   1651         dev->sc_tcnt = dev->sc_dmago(dev, acb->sc_pa.dc_addr,
   1652                                           acb->sc_pa.dc_count, dmaflags);
   1653 #ifdef DEBUG
   1654         dev->sc_dmatimo = dev->sc_tcnt ? 1 : 0;
   1655 #endif
   1656     } else
   1657         dev->sc_dmacmd = 0; /* Don't use DMA */
   1658 
   1659     acb->sc_dmacmd = dev->sc_dmacmd;
   1660 
   1661 #ifdef DEBUG
   1662     if ( data_pointer_debug > 1 ) {
   1663         printf("sbicgo dmago:%d(%x:%x) dmacmd=0x%02x\n", dev->target,
   1664                                            dev->sc_cur->dc_addr,
   1665                                            dev->sc_tcnt,
   1666                                            dev->sc_dmacmd);
   1667     }
   1668 #endif
   1669 
   1670     /*
   1671      * Lets cycle a while then let the interrupt handler take over.
   1672      */
   1673     GET_SBIC_asr(regs, asr);
   1674 
   1675     do {
   1676 
   1677         QPRINTF(("go "));
   1678 
   1679         /*
   1680          * Handle the new phase
   1681          */
   1682         i = sbicnextstate(dev, csr, asr);
   1683 #if 0
   1684         WAIT_CIP(regs);
   1685 #endif
   1686         if ( i == SBIC_STATE_RUNNING ) {
   1687             GET_SBIC_asr(regs, asr);
   1688 
   1689             if ( asr & SBIC_ASR_LCI )
   1690                 printf("sbicgo: LCI asr:%02x csr:%02x\n", asr, csr);
   1691 
   1692             if ( asr & SBIC_ASR_INT )
   1693                 GET_SBIC_csr(regs, csr);
   1694         }
   1695 
   1696     } while ( i == SBIC_STATE_RUNNING && asr & (SBIC_ASR_INT|SBIC_ASR_LCI) );
   1697 
   1698     if ( i == SBIC_STATE_DONE ) {
   1699         if ( dev->sc_stat[0] == 0xff )
   1700 #if 0
   1701             printf("sbicgo: done & stat = 0xff\n");
   1702 #else
   1703             ;
   1704 #endif
   1705         else
   1706             return 1;   /* Did we really finish that fast? */
   1707     }
   1708 
   1709     return 0;
   1710 }
   1711 
   1712 
   1713 int
   1714 sbicintr(dev)
   1715     struct sbic_softc   *dev;
   1716 {
   1717     sbic_regmap_p       regs = dev->sc_sbicp;
   1718     u_char              asr,
   1719                         csr;
   1720     int                 i;
   1721 
   1722     /*
   1723      * pending interrupt?
   1724      */
   1725     GET_SBIC_asr (regs, asr);
   1726     if ( (asr & SBIC_ASR_INT) == 0 )
   1727         return(0);
   1728 
   1729     GET_SBIC_csr(regs, csr);
   1730 
   1731     do {
   1732 
   1733         QPRINTF(("intr[0x%x]", csr));
   1734 
   1735         i = sbicnextstate(dev, csr, asr);
   1736 #if 0
   1737         WAIT_CIP(regs);
   1738 #endif
   1739         if ( i == SBIC_STATE_RUNNING ) {
   1740             GET_SBIC_asr(regs, asr);
   1741 
   1742             if ( asr & SBIC_ASR_LCI )
   1743                 printf("sbicgo: LCI asr:%02x csr:%02x\n", asr, csr);
   1744 
   1745             if ( asr & SBIC_ASR_INT )
   1746                 GET_SBIC_csr(regs, csr);
   1747         }
   1748 
   1749     } while ( i == SBIC_STATE_RUNNING && asr & (SBIC_ASR_INT|SBIC_ASR_LCI) );
   1750 
   1751     QPRINTF(("intr done. state=%d, asr=0x%02x\n", i, asr));
   1752 
   1753     return(1);
   1754 }
   1755 
   1756 /*
   1757  * Run commands and wait for disconnect.
   1758  * This is only ever called when a command is in progress, when we
   1759  * want to busy wait for it to finish.
   1760  */
   1761 int
   1762 sbicpoll(dev)
   1763     struct sbic_softc   *dev;
   1764 {
   1765     sbic_regmap_p       regs = dev->sc_sbicp;
   1766     u_char              asr,
   1767                         csr;
   1768     int                 i;
   1769 
   1770     /*
   1771      * Wait for the next interrupt
   1772      */
   1773     SBIC_WAIT(regs, SBIC_ASR_INT, sbic_cmd_wait);
   1774 
   1775     do {
   1776         GET_SBIC_asr (regs, asr);
   1777 
   1778         if ( asr & SBIC_ASR_INT )
   1779             GET_SBIC_csr(regs, csr);
   1780 
   1781         QPRINTF(("poll[0x%x]", csr));
   1782 
   1783         /*
   1784          * Handle it
   1785          */
   1786         i = sbicnextstate(dev, csr, asr);
   1787 
   1788         WAIT_CIP(regs);
   1789         GET_SBIC_asr(regs, asr);
   1790 
   1791         /*
   1792          * tapes may take a loooong time..
   1793          */
   1794         while ( asr & SBIC_ASR_BSY ) {
   1795             u_char z = 0;
   1796 
   1797             if ( asr & SBIC_ASR_DBR ) {
   1798                 printf("sbipoll: Waiting while sbic is jammed, CSR:%02x,ASR:%02x\n", csr,asr);
   1799 #ifdef DDB
   1800                 Debugger();
   1801 #endif
   1802                 /*
   1803                  * SBIC is jammed
   1804                  * DUNNO which direction
   1805                  * Try old direction
   1806                  */
   1807                 GET_SBIC_data(regs, z);
   1808                 GET_SBIC_asr(regs, asr);
   1809 
   1810                 if ( asr & SBIC_ASR_DBR ) /* Wants us to write */
   1811                     SET_SBIC_data(regs, z);
   1812             }
   1813 
   1814             GET_SBIC_asr(regs, asr);
   1815         }
   1816 
   1817         if ( asr & SBIC_ASR_LCI )
   1818             printf("sbicpoll: LCI asr:%02x csr:%02x\n", asr,csr);
   1819         else
   1820         if ( i == SBIC_STATE_RUNNING ) /* BSY */
   1821             SBIC_WAIT(regs, SBIC_ASR_INT, sbic_cmd_wait);
   1822 
   1823     } while ( i == SBIC_STATE_RUNNING );
   1824 
   1825     return(1);
   1826 }
   1827 
   1828 /*
   1829  * Handle a single msgin
   1830  */
   1831 int
   1832 sbicmsgin(dev)
   1833     struct sbic_softc   *dev;
   1834 {
   1835     sbic_regmap_p       regs = dev->sc_sbicp;
   1836     int                 recvlen = 1;
   1837     u_char              asr,
   1838                         csr,
   1839                         *tmpaddr,
   1840                         *msgaddr;
   1841 
   1842     tmpaddr = msgaddr = dev->sc_msg;
   1843 
   1844     tmpaddr[0] = 0xff;
   1845     tmpaddr[1] = 0xff;
   1846 
   1847     GET_SBIC_asr(regs, asr);
   1848 
   1849 #ifdef DEBUG
   1850     if ( reselect_debug > 1 )
   1851         printf("sbicmsgin asr=%02x\n", asr);
   1852 #endif
   1853 
   1854     GET_SBIC_selid (regs, csr);
   1855     SET_SBIC_selid (regs, csr | SBIC_SID_FROM_SCSI);
   1856 
   1857     SBIC_TC_PUT(regs, 0);
   1858     SET_SBIC_control(regs, SBIC_CTL_EDI | SBIC_CTL_IDI);
   1859 
   1860     do {
   1861         while( recvlen-- ) {
   1862 
   1863             /*
   1864              * Fetch the next byte of the message
   1865              */
   1866             RECV_BYTE(regs, *tmpaddr);
   1867 
   1868             /*
   1869              * get the command completion interrupt, or we
   1870              * can't send a new command (LCI)
   1871              */
   1872             SBIC_WAIT(regs, SBIC_ASR_INT, 0);
   1873             GET_SBIC_csr(regs, csr);
   1874 
   1875 #ifdef DEBUG
   1876             if ( reselect_debug > 1 )
   1877                 printf("sbicmsgin: got %02x csr %02x\n", *tmpaddr, csr);
   1878 #endif
   1879 
   1880             tmpaddr++;
   1881 
   1882             if ( recvlen ) {
   1883                 /*
   1884                  * Clear ACK, and wait for the interrupt for the next byte
   1885                  */
   1886                 SET_SBIC_cmd(regs, SBIC_CMD_CLR_ACK);
   1887                 SBIC_WAIT(regs, SBIC_ASR_INT, 0);
   1888                 GET_SBIC_csr(regs, csr);
   1889             }
   1890         }
   1891 
   1892         if ( msgaddr[0] == 0xff ) {
   1893             printf("sbicmsgin: sbic swallowed our message\n");
   1894             break;
   1895         }
   1896 
   1897 #ifdef DEBUG
   1898         if ( sync_debug ) {
   1899             GET_SBIC_asr(regs, asr);
   1900             printf("msgin done csr 0x%x asr 0x%x msg 0x%x\n", csr, asr, msgaddr[0]);
   1901         }
   1902 #endif
   1903         /*
   1904          * test whether this is a reply to our sync
   1905          * request
   1906          */
   1907         if ( MSG_ISIDENTIFY(msgaddr[0]) ) {
   1908 
   1909             /*
   1910              * Got IFFY msg -- ack it
   1911              */
   1912             QPRINTF(("IFFY"));
   1913 
   1914         } else
   1915         if ( msgaddr[0] == MSG_REJECT &&
   1916              dev->sc_sync[dev->target].state == SYNC_SENT) {
   1917 
   1918             /*
   1919              * Target probably rejected our Sync negotiation.
   1920              */
   1921             QPRINTF(("REJECT of SYN"));
   1922 
   1923 #ifdef DEBUG
   1924             if ( sync_debug )
   1925                 printf("target %d rejected sync, going async\n", dev->target);
   1926 #endif
   1927 
   1928             dev->sc_sync[dev->target].period = sbic_min_period;
   1929             dev->sc_sync[dev->target].offset = 0;
   1930             dev->sc_sync[dev->target].state  = SYNC_DONE;
   1931             SET_SBIC_syn(regs, SBIC_SYN(dev->sc_sync[dev->target].offset,
   1932                                         dev->sc_sync[dev->target].period));
   1933 
   1934         } else
   1935         if ( msgaddr[0] == MSG_REJECT ) {
   1936 
   1937             /*
   1938              * we'll never REJECt a REJECT message..
   1939              */
   1940             QPRINTF(("REJECT"));
   1941 
   1942         } else
   1943         if ( msgaddr[0] == MSG_SAVE_DATA_PTR ) {
   1944 
   1945             /*
   1946              * don't reject this either.
   1947              */
   1948             QPRINTF(("MSG_SAVE_DATA_PTR"));
   1949 
   1950         } else
   1951         if ( msgaddr[0] == MSG_RESTORE_PTR ) {
   1952 
   1953             /*
   1954              * don't reject this either.
   1955              */
   1956             QPRINTF(("MSG_RESTORE_PTR"));
   1957 
   1958         } else
   1959         if ( msgaddr[0] == MSG_DISCONNECT ) {
   1960 
   1961             /*
   1962              * Target is disconnecting...
   1963              */
   1964             QPRINTF(("DISCONNECT"));
   1965 
   1966 #ifdef DEBUG
   1967             if ( reselect_debug > 1 && msgaddr[0] == MSG_DISCONNECT )
   1968                 printf("sbicmsgin: got disconnect msg %s\n",
   1969                        (dev->sc_flags & SBICF_ICMD) ? "rejecting" : "");
   1970 #endif
   1971 
   1972             if ( dev->sc_flags & SBICF_ICMD ) {
   1973                 /*
   1974                  * We're in immediate mode. Prevent disconnects.
   1975                  * prepare to reject the message, NACK
   1976                  */
   1977                 SET_SBIC_cmd(regs, SBIC_CMD_SET_ATN);
   1978                 WAIT_CIP(regs);
   1979             }
   1980 
   1981         } else
   1982         if ( msgaddr[0] == MSG_CMD_COMPLETE ) {
   1983 
   1984             /*
   1985              * !! KLUDGE ALERT !! quite a few drives don't seem to
   1986              * really like the current way of sending the
   1987              * sync-handshake together with the ident-message, and
   1988              * they react by sending command-complete and
   1989              * disconnecting right after returning the valid sync
   1990              * handshake. So, all I can do is reselect the drive,
   1991              * and hope it won't disconnect again. I don't think
   1992              * this is valid behavior, but I can't help fixing a
   1993              * problem that apparently exists.
   1994              *
   1995              * Note: we should not get here on `normal' command
   1996              * completion, as that condition is handled by the
   1997              * high-level sel&xfer resume command used to walk
   1998              * thru status/cc-phase.
   1999              */
   2000             QPRINTF(("CMD_COMPLETE"));
   2001 
   2002 #ifdef DEBUG
   2003             if ( sync_debug )
   2004                 printf ("GOT MSG %d! target %d acting weird.."
   2005                         " waiting for disconnect...\n", msgaddr[0], dev->target);
   2006 #endif
   2007 
   2008             /*
   2009              * Check to see if sbic is handling this
   2010              */
   2011             GET_SBIC_asr(regs, asr);
   2012 
   2013             /*
   2014              * XXXSCW: I'm not convinced of this, we haven't negated ACK yet...
   2015              */
   2016             if ( asr & SBIC_ASR_BSY )
   2017                 return SBIC_STATE_RUNNING;
   2018 
   2019             /*
   2020              * Let's try this: Assume it works and set status to 00
   2021              */
   2022             dev->sc_stat[0] = 0;
   2023 
   2024         } else
   2025         if ( msgaddr[0] == MSG_EXT_MESSAGE && tmpaddr == &(msgaddr[1]) ) {
   2026 
   2027             /*
   2028              * Target is sending us an extended message. We'll assume it's
   2029              * the response to our Sync. negotiation.
   2030              */
   2031             QPRINTF(("ExtMSG\n"));
   2032 
   2033             /*
   2034              * Read in whole extended message. First, negate ACK to accept
   2035              * the MSG_EXT_MESSAGE byte...
   2036              */
   2037             SET_SBIC_cmd(regs, SBIC_CMD_CLR_ACK);
   2038 
   2039             /*
   2040              * Wait for the interrupt for the next byte (length)
   2041              */
   2042             SBIC_WAIT(regs, SBIC_ASR_INT, 0);
   2043             GET_SBIC_csr(regs, csr);
   2044 
   2045 #ifdef  DEBUG
   2046             QPRINTF(("CLR ACK csr %02x\n", csr));
   2047 #endif
   2048 
   2049             /*
   2050              * Read the length byte
   2051              */
   2052             RECV_BYTE(regs, *tmpaddr);
   2053 
   2054             /*
   2055              * Wait for command completion IRQ
   2056              */
   2057             SBIC_WAIT(regs, SBIC_ASR_INT, 0);
   2058             GET_SBIC_csr(regs, csr);
   2059 
   2060             /*
   2061              * Reload the loop counter
   2062              */
   2063             recvlen = *tmpaddr++;
   2064 
   2065             QPRINTF(("Recving ext msg, csr %02x len %02x\n", csr, recvlen));
   2066 
   2067         } else
   2068         if ( msgaddr[0] == MSG_EXT_MESSAGE && msgaddr[1] == 3 &&
   2069              msgaddr[2] == MSG_SYNC_REQ ) {
   2070 
   2071             /*
   2072              * We've received the complete Extended Message Sync. Request...
   2073              */
   2074             QPRINTF(("SYN"));
   2075 
   2076             /*
   2077              * Compute the required Transfer Period for the WD chip...
   2078              */
   2079             dev->sc_sync[dev->target].period = sbicfromscsiperiod(dev, msgaddr[3]);
   2080             dev->sc_sync[dev->target].offset = msgaddr[4];
   2081             dev->sc_sync[dev->target].state  = SYNC_DONE;
   2082 
   2083             /*
   2084              * Put the WD chip in synchronous mode
   2085              */
   2086             SET_SBIC_syn(regs, SBIC_SYN(dev->sc_sync[dev->target].offset,
   2087                                         dev->sc_sync[dev->target].period));
   2088 #ifdef  DEBUG
   2089             if ( sync_debug )
   2090                 printf("msgin(%d): sync reg = 0x%02x\n", dev->target,
   2091                                 SBIC_SYN(dev->sc_sync[dev->target].offset,
   2092                                          dev->sc_sync[dev->target].period));
   2093 #endif
   2094 
   2095             printf("%s: target %d now synchronous, period=%dns, offset=%d.\n",
   2096                    dev->sc_dev.dv_xname, dev->target,
   2097                    msgaddr[3] * 4, msgaddr[4]);
   2098 
   2099         } else {
   2100 
   2101             /*
   2102              * We don't support whatever this message is...
   2103              */
   2104 #ifdef DEBUG
   2105             if ( sbic_debug || sync_debug )
   2106                 printf ("sbicmsgin: Rejecting message 0x%02x\n", msgaddr[0]);
   2107 #endif
   2108 
   2109             /*
   2110              * prepare to reject the message, NACK
   2111              */
   2112             SET_SBIC_cmd(regs, SBIC_CMD_SET_ATN);
   2113             WAIT_CIP(regs);
   2114         }
   2115 
   2116         /*
   2117          * Negate ACK to complete the transfer
   2118          */
   2119         SET_SBIC_cmd(regs, SBIC_CMD_CLR_ACK);
   2120 
   2121         /*
   2122          * Wait for the interrupt for the next byte, or phase change.
   2123          * Only read the CSR if we have more data to transfer.
   2124          * XXXSCW: We should really verify that we're still in MSG IN phase
   2125          * before blindly going back around this loop, but that would mean
   2126          * we read the CSR... <sigh>
   2127          */
   2128         SBIC_WAIT(regs, SBIC_ASR_INT, 0);
   2129         if ( recvlen > 0 )
   2130             GET_SBIC_csr(regs, csr);
   2131 
   2132     } while ( recvlen > 0 );
   2133 
   2134     /*
   2135      * Should still have one CSR to read
   2136      */
   2137     return SBIC_STATE_RUNNING;
   2138 }
   2139 
   2140 
   2141 /*
   2142  * sbicnextstate()
   2143  * return:
   2144  *      SBIC_STATE_DONE        == done
   2145  *      SBIC_STATE_RUNNING     == working
   2146  *      SBIC_STATE_DISCONNECT  == disconnected
   2147  *      SBIC_STATE_ERROR       == error
   2148  */
   2149 int
   2150 sbicnextstate(dev, csr, asr)
   2151     struct sbic_softc   *dev;
   2152     u_char              csr,
   2153                         asr;
   2154 {
   2155     sbic_regmap_p       regs = dev->sc_sbicp;
   2156     struct sbic_acb     *acb = dev->sc_nexus;
   2157 
   2158     QPRINTF(("next[%02x,%02x]: ",asr,csr));
   2159 
   2160     switch (csr) {
   2161 
   2162       case SBIC_CSR_XFERRED | CMD_PHASE:
   2163       case SBIC_CSR_MIS     | CMD_PHASE:
   2164       case SBIC_CSR_MIS_1   | CMD_PHASE:
   2165       case SBIC_CSR_MIS_2   | CMD_PHASE:
   2166         {
   2167             if ( sbicxfout(regs, acb->clen, &acb->cmd) )
   2168                 goto abort;
   2169         }
   2170         break;
   2171 
   2172       case SBIC_CSR_XFERRED | STATUS_PHASE:
   2173       case SBIC_CSR_MIS     | STATUS_PHASE:
   2174       case SBIC_CSR_MIS_1   | STATUS_PHASE:
   2175       case SBIC_CSR_MIS_2   | STATUS_PHASE:
   2176         {
   2177             SET_SBIC_control(regs, SBIC_CTL_EDI | SBIC_CTL_IDI);
   2178 
   2179             /*
   2180              * this should be the normal i/o completion case.
   2181              * get the status & cmd complete msg then let the
   2182              * device driver look at what happened.
   2183              */
   2184             sbicxfdone(dev);
   2185 
   2186 #ifdef DEBUG
   2187             dev->sc_dmatimo = 0;
   2188             if ( data_pointer_debug > 1 )
   2189                 printf("next dmastop: %d(%x:%x)\n", dev->target,
   2190                                                     dev->sc_cur->dc_addr,
   2191                                                     dev->sc_tcnt);
   2192 #endif
   2193             /*
   2194              * Stop the DMA chip
   2195              */
   2196             dev->sc_dmastop(dev);
   2197 
   2198             dev->sc_flags &= ~(SBICF_INDMA | SBICF_DCFLUSH);
   2199 
   2200             /*
   2201              * Indicate to the upper layers that the command is done
   2202              */
   2203             sbic_scsidone(acb, dev->sc_stat[0]);
   2204 
   2205             return SBIC_STATE_DONE;
   2206         }
   2207 
   2208       case SBIC_CSR_XFERRED | DATA_OUT_PHASE:
   2209       case SBIC_CSR_XFERRED | DATA_IN_PHASE:
   2210       case SBIC_CSR_MIS     | DATA_OUT_PHASE:
   2211       case SBIC_CSR_MIS     | DATA_IN_PHASE:
   2212       case SBIC_CSR_MIS_1   | DATA_OUT_PHASE:
   2213       case SBIC_CSR_MIS_1   | DATA_IN_PHASE:
   2214       case SBIC_CSR_MIS_2   | DATA_OUT_PHASE:
   2215       case SBIC_CSR_MIS_2   | DATA_IN_PHASE:
   2216         {
   2217             /*
   2218              * Verify that we expected to transfer data...
   2219              */
   2220             if ( acb->sc_kv.dc_count <= 0 ) {
   2221                 printf("next: DATA phase with xfer count == %d, asr:0x%02x csr:0x%02x\n",
   2222                         acb->sc_kv.dc_count, asr, csr);
   2223                 goto abort;
   2224             }
   2225 
   2226             /*
   2227              * Should we transfer using PIO or DMA ?
   2228              */
   2229             if ( dev->sc_xs->flags & SCSI_POLL || dev->sc_flags & SBICF_ICMD ||
   2230                  acb->sc_dmacmd == 0 ) {
   2231 
   2232                 /*
   2233                  * Do PIO transfer
   2234                  */
   2235                 int     i;
   2236 
   2237 #ifdef DEBUG
   2238                 if ( data_pointer_debug > 1 )
   2239                     printf("next PIO: %d(%x:%x)\n", dev->target,
   2240                                                     acb->sc_kv.dc_addr,
   2241                                                     acb->sc_kv.dc_count);
   2242 #endif
   2243 
   2244                 if ( SBIC_PHASE(csr) == DATA_IN_PHASE )
   2245                     /*
   2246                      * data in
   2247                      */
   2248                     i = sbicxfin(regs, acb->sc_kv.dc_count,
   2249                                        acb->sc_kv.dc_addr);
   2250                 else
   2251                     /*
   2252                      * data out
   2253                      */
   2254                     i = sbicxfout(regs, acb->sc_kv.dc_count,
   2255                                         acb->sc_kv.dc_addr);
   2256 
   2257                 acb->sc_kv.dc_addr += (acb->sc_kv.dc_count - i);
   2258                 acb->sc_kv.dc_count = i;
   2259 
   2260                 /*
   2261                  * Update current count...
   2262                  */
   2263                 acb->sc_tcnt = dev->sc_tcnt = i;
   2264 
   2265                 dev->sc_flags &= ~SBICF_INDMA;
   2266 
   2267             } else {
   2268 
   2269                 /*
   2270                  * Do DMA transfer
   2271                  * set next dma addr and dec count
   2272                  */
   2273                 sbic_save_ptrs(dev);
   2274                 sbic_load_ptrs(dev);
   2275 
   2276                 SET_SBIC_control(regs, SBIC_CTL_EDI | SBIC_CTL_IDI |
   2277                                        SBIC_MACHINE_DMA_MODE);
   2278 
   2279 #ifdef DEBUG
   2280                 dev->sc_dmatimo = 1;
   2281                 if ( data_pointer_debug > 1 )
   2282                     printf("next DMA: %d(%x:%x)\n", dev->target,
   2283                                                     dev->sc_cur->dc_addr,
   2284                                                     dev->sc_tcnt);
   2285 #endif
   2286                 /*
   2287                  * Start the DMA chip going
   2288                  */
   2289                 dev->sc_tcnt = dev->sc_dmanext(dev);
   2290 
   2291                 /*
   2292                  * Tell the WD chip how much to transfer this time around
   2293                  */
   2294                 SBIC_TC_PUT(regs, (unsigned)dev->sc_tcnt);
   2295 
   2296                 /*
   2297                  * Start the transfer
   2298                  */
   2299                 SET_SBIC_cmd(regs, SBIC_CMD_XFER_INFO);
   2300 
   2301                 /*
   2302                  * Indicate that we're in DMA mode
   2303                  */
   2304                 dev->sc_flags |= SBICF_INDMA;
   2305             }
   2306         }
   2307         break;
   2308 
   2309       case SBIC_CSR_XFERRED | MESG_IN_PHASE:
   2310       case SBIC_CSR_MIS     | MESG_IN_PHASE:
   2311       case SBIC_CSR_MIS_1   | MESG_IN_PHASE:
   2312       case SBIC_CSR_MIS_2   | MESG_IN_PHASE:
   2313         {
   2314             sbic_save_ptrs(dev);
   2315 
   2316             /*
   2317              * Handle a single message in...
   2318              */
   2319             return sbicmsgin(dev);
   2320         }
   2321 
   2322       case SBIC_CSR_MSGIN_W_ACK:
   2323         {
   2324             /*
   2325              * We should never see this since it's handled in 'sbicmsgin()'
   2326              * but just for the sake of paranoia...
   2327              */
   2328             SET_SBIC_cmd(regs, SBIC_CMD_CLR_ACK); /* Dunno what I'm ACKing */
   2329             printf("Acking unknown msgin CSR:%02x",csr);
   2330         }
   2331         break;
   2332 
   2333       case SBIC_CSR_XFERRED | MESG_OUT_PHASE:
   2334       case SBIC_CSR_MIS     | MESG_OUT_PHASE:
   2335       case SBIC_CSR_MIS_1   | MESG_OUT_PHASE:
   2336       case SBIC_CSR_MIS_2   | MESG_OUT_PHASE:
   2337         {
   2338             /*
   2339              * We only ever handle a message out phase here for sending a
   2340              * REJECT message.
   2341              */
   2342             sbic_save_ptrs(dev);
   2343 
   2344 #ifdef DEBUG
   2345             if (sync_debug)
   2346                 printf ("sending REJECT msg to last msg.\n");
   2347 #endif
   2348 
   2349             SEND_BYTE(regs, MSG_REJECT);
   2350             WAIT_CIP(regs);
   2351         }
   2352         break;
   2353 
   2354       case SBIC_CSR_DISC:
   2355       case SBIC_CSR_DISC_1:
   2356         {
   2357             /*
   2358              * Try to schedule another target
   2359              */
   2360             sbic_save_ptrs(dev);
   2361 
   2362             dev->sc_flags &= ~SBICF_SELECTED;
   2363 
   2364 #ifdef DEBUG
   2365             if ( reselect_debug > 1 )
   2366                 printf("sbicnext target %d disconnected\n", dev->target);
   2367 #endif
   2368 
   2369             TAILQ_INSERT_HEAD(&dev->nexus_list, acb, chain);
   2370 
   2371             ++dev->sc_tinfo[dev->target].dconns;
   2372 
   2373             dev->sc_nexus = NULL;
   2374             dev->sc_xs    = NULL;
   2375 
   2376             if ( acb->xs->flags & SCSI_POLL || dev->sc_flags & SBICF_ICMD ||
   2377                                                !sbic_parallel_operations )
   2378                 return SBIC_STATE_DISCONNECT;
   2379 
   2380             QPRINTF(("sbicnext: calling sbic_sched\n"));
   2381 
   2382             sbic_sched(dev);
   2383 
   2384             QPRINTF(("sbicnext: sbic_sched returned\n"));
   2385 
   2386             return SBIC_STATE_DISCONNECT;
   2387         }
   2388 
   2389       case SBIC_CSR_RSLT_NI:
   2390       case SBIC_CSR_RSLT_IFY:
   2391         {
   2392             /*
   2393              * A reselection.
   2394              * Note that since we don't enable Advanced Features (assuming
   2395              * the WD chip is at least the 'A' revision), we're only ever
   2396              * likely to see the 'SBIC_CSR_RSLT_NI' status. But for the
   2397              * hell of it, we'll handle it anyway, for all the extra code
   2398              * it needs...
   2399              */
   2400             u_char  newtarget,
   2401                     newlun;
   2402 
   2403             GET_SBIC_rselid(regs, newtarget);
   2404 
   2405             /*
   2406              * check SBIC_RID_SIV?
   2407              */
   2408             newtarget &= SBIC_RID_MASK;
   2409 
   2410             if ( csr == SBIC_CSR_RSLT_IFY ) {
   2411 
   2412                 /*
   2413                  * Read Identify msg to avoid lockup
   2414                  */
   2415                 GET_SBIC_data(regs, newlun);
   2416                 WAIT_CIP(regs);
   2417                 newlun &= SBIC_TLUN_MASK;
   2418 
   2419             } else {
   2420 
   2421                 /*
   2422                  * Need to read Identify message the hard way, assuming
   2423                  * the target even sends us one...
   2424                  */
   2425                 for (newlun = 255; newlun; --newlun) {
   2426                     GET_SBIC_asr(regs, asr);
   2427                     if (asr & SBIC_ASR_INT)
   2428                         break;
   2429                     delay(10);
   2430                 }
   2431 
   2432                 /*
   2433                  * If we didn't get an interrupt, somethink's up
   2434                  */
   2435                 if ( (asr & SBIC_ASR_INT) == 0 ) {
   2436                     printf("%s: Reselect without identify? asr %x\n",
   2437                             dev->sc_dev.dv_xname, asr);
   2438                     newlun = 0; /* XXXX */
   2439                 } else {
   2440                     /*
   2441                      * We got an interrupt, verify that it's a change to
   2442                      * message in phase, and if so read the message.
   2443                      */
   2444                     GET_SBIC_csr(regs,csr);
   2445 
   2446                     if ( csr == SBIC_CSR_MIS   | MESG_IN_PHASE ||
   2447                          csr == SBIC_CSR_MIS_1 | MESG_IN_PHASE ||
   2448                          csr == SBIC_CSR_MIS_2 | MESG_IN_PHASE ) {
   2449                         /*
   2450                          * Yup, gone to message in. Fetch the target LUN
   2451                          */
   2452                         sbicmsgin(dev);
   2453                         newlun = dev->sc_msg[0] & 0x07;
   2454 
   2455                     } else {
   2456                         /*
   2457                          * Whoops! Target didn't go to message in phase!!
   2458                          */
   2459                         printf("RSLT_NI - not MESG_IN_PHASE %x\n", csr);
   2460                         newlun = 0; /* XXXSCW */
   2461                     }
   2462                 }
   2463             }
   2464 
   2465             /*
   2466              * Ok, we have the identity of the reselecting target.
   2467              */
   2468 #ifdef DEBUG
   2469             if ( reselect_debug > 1 ||
   2470                 (reselect_debug && csr == SBIC_CSR_RSLT_NI) ) {
   2471                 printf("sbicnext: reselect %s from targ %d lun %d\n",
   2472                         csr == SBIC_CSR_RSLT_NI ? "NI" : "IFY", newtarget, newlun);
   2473             }
   2474 #endif
   2475 
   2476             if ( dev->sc_nexus ) {
   2477                 /*
   2478                  * Whoops! We've been reselected with an command in progress!
   2479                  * The best we can do is to put the current command back on the
   2480                  * ready list and hope for the best.
   2481                  */
   2482 #ifdef DEBUG
   2483                 if ( reselect_debug > 1 ) {
   2484                     printf("%s: reselect %s with active command\n",
   2485                         dev->sc_dev.dv_xname,
   2486                         csr == SBIC_CSR_RSLT_NI ? "NI" : "IFY");
   2487                 }
   2488 #endif
   2489 
   2490                 TAILQ_INSERT_HEAD(&dev->ready_list, dev->sc_nexus, chain);
   2491 
   2492                 dev->sc_tinfo[dev->target].lubusy &= ~(1 << dev->lun);
   2493 
   2494                 dev->sc_nexus = NULL;
   2495                 dev->sc_xs    = NULL;
   2496             }
   2497 
   2498             /*
   2499              * Reload sync values for this target
   2500              */
   2501             if ( dev->sc_sync[newtarget].state == SYNC_DONE )
   2502                 SET_SBIC_syn(regs, SBIC_SYN (dev->sc_sync[newtarget].offset,
   2503                                              dev->sc_sync[newtarget].period));
   2504             else
   2505                 SET_SBIC_syn(regs, SBIC_SYN (0, sbic_min_period));
   2506 
   2507             /*
   2508              * Loop through the nexus list until we find the saved entry
   2509              * for the reselecting target...
   2510              */
   2511             for (acb = dev->nexus_list.tqh_first; acb;
   2512                                                   acb = acb->chain.tqe_next) {
   2513 
   2514                 if ( acb->xs->sc_link->scsipi_scsi.target == newtarget &&
   2515                      acb->xs->sc_link->scsipi_scsi.lun    == newlun) {
   2516                     /*
   2517                      * We've found the saved entry. Dequeue it, and
   2518                      * make it current again.
   2519                      */
   2520                     TAILQ_REMOVE(&dev->nexus_list, acb, chain);
   2521 
   2522                     dev->sc_nexus  = acb;
   2523                     dev->sc_xs     = acb->xs;
   2524                     dev->sc_flags |= SBICF_SELECTED;
   2525                     dev->target    = newtarget;
   2526                     dev->lun       = newlun;
   2527                     break;
   2528                 }
   2529             }
   2530 
   2531             if ( acb == NULL ) {
   2532                 printf("%s: reselect %s targ %d not in nexus_list %x\n",
   2533                         dev->sc_dev.dv_xname,
   2534                         csr == SBIC_CSR_RSLT_NI ? "NI" : "IFY", newtarget,
   2535                         &dev->nexus_list.tqh_first);
   2536                 panic("bad reselect in sbic");
   2537             }
   2538 
   2539             if ( csr == SBIC_CSR_RSLT_IFY )
   2540                 SET_SBIC_cmd(regs, SBIC_CMD_CLR_ACK);
   2541         }
   2542         break;
   2543 
   2544       default:
   2545         abort:
   2546         {
   2547             /*
   2548              * Something unexpected happened -- deal with it.
   2549              */
   2550             printf("next: aborting asr 0x%02x csr 0x%02x\n", asr, csr);
   2551 
   2552 #ifdef DDB
   2553             Debugger();
   2554 #endif
   2555 
   2556 #ifdef DEBUG
   2557             dev->sc_dmatimo = 0;
   2558             if ( data_pointer_debug > 1 )
   2559                 printf("next dmastop: %d(%x:%x)\n", dev->target,
   2560                                                     dev->sc_cur->dc_addr,
   2561                                                     dev->sc_tcnt);
   2562 #endif
   2563 
   2564             dev->sc_dmastop(dev);
   2565             SET_SBIC_control(regs, SBIC_CTL_EDI | SBIC_CTL_IDI);
   2566             if ( dev->sc_xs ) sbicerror(dev, csr);
   2567             sbicabort(dev, "next");
   2568 
   2569             if ( dev->sc_flags & SBICF_INDMA ) {
   2570                 dev->sc_flags &= ~(SBICF_INDMA | SBICF_DCFLUSH);
   2571 
   2572 #ifdef DEBUG
   2573                 dev->sc_dmatimo = 0;
   2574                 if ( data_pointer_debug > 1 )
   2575                     printf("next dmastop: %d(%x:%x)\n", dev->target,
   2576                                                         dev->sc_cur->dc_addr,
   2577                                                         dev->sc_tcnt);
   2578 #endif
   2579                 sbic_scsidone(acb, -1);
   2580             }
   2581 
   2582             return SBIC_STATE_ERROR;
   2583         }
   2584     }
   2585 
   2586     return(SBIC_STATE_RUNNING);
   2587 }
   2588 
   2589 
   2590 /*
   2591  * Check if DMA can not be used with specified buffer
   2592  */
   2593 int
   2594 sbiccheckdmap(bp, len, mask)
   2595     void    *bp;
   2596     u_long  len,
   2597             mask;
   2598 {
   2599     u_char  *buffer;
   2600     u_long  phy_buf;
   2601     u_long  phy_len;
   2602 
   2603     buffer = bp;
   2604 
   2605     if ( len == 0 )
   2606         return(1);
   2607 
   2608     while ( len ) {
   2609 
   2610         phy_buf = kvtop(buffer);
   2611         phy_len = NBPG - ((int) buffer & PGOFSET);
   2612 
   2613         if ( len < phy_len )
   2614             phy_len = len;
   2615 
   2616         if ( phy_buf & mask )
   2617             return(1);
   2618 
   2619         buffer += phy_len;
   2620         len    -= phy_len;
   2621     }
   2622 
   2623     return(0);
   2624 }
   2625 
   2626 int
   2627 sbictoscsiperiod(dev, a)
   2628     struct sbic_softc   *dev;
   2629     int                 a;
   2630 {
   2631     unsigned int fs;
   2632 
   2633     /*
   2634      * cycle = DIV / (2 * CLK)
   2635      * DIV = FS + 2
   2636      * best we can do is 200ns at 20Mhz, 2 cycles
   2637      */
   2638 
   2639     GET_SBIC_myid(dev->sc_sbicp, fs);
   2640 
   2641     fs = (fs >> 6) + 2;         /* DIV */
   2642 
   2643     fs = (fs * 10000) / (dev->sc_clkfreq << 1); /* Cycle, in ns */
   2644 
   2645     if ( a < 2 )
   2646         a = 8;                  /* map to Cycles */
   2647 
   2648     return ( (fs * a) >> 2 );   /* in 4 ns units */
   2649 }
   2650 
   2651 int
   2652 sbicfromscsiperiod(dev, p)
   2653     struct sbic_softc   *dev;
   2654     int                 p;
   2655 {
   2656     unsigned    fs,
   2657                 ret;
   2658 
   2659     /*
   2660      * Just the inverse of the above
   2661      */
   2662     GET_SBIC_myid(dev->sc_sbicp, fs);
   2663 
   2664     fs = (fs >> 6) + 2;     /* DIV */
   2665 
   2666     fs = (fs * 10000) / (dev->sc_clkfreq << 1); /* Cycle, in ns */
   2667 
   2668     ret = p << 2;           /* in ns units */
   2669     ret = ret / fs;         /* in Cycles */
   2670 
   2671     if ( ret < sbic_min_period )
   2672         return(sbic_min_period);
   2673 
   2674     /*
   2675      * verify rounding
   2676      */
   2677     if ( sbictoscsiperiod(dev, ret) < p )
   2678         ret++;
   2679 
   2680     return( (ret >= 8) ? 0 : ret );
   2681 }
   2682 
   2683 #ifdef DEBUG
   2684 void
   2685 sbictimeout(dev)
   2686     struct sbic_softc   *dev;
   2687 {
   2688     int     s,
   2689             asr;
   2690 
   2691     s = splbio();
   2692 
   2693     if ( dev->sc_dmatimo ) {
   2694 
   2695         if ( dev->sc_dmatimo > 1 ) {
   2696 
   2697             printf("%s: dma timeout #%d\n", dev->sc_dev.dv_xname,
   2698                                             dev->sc_dmatimo - 1);
   2699 
   2700             GET_SBIC_asr(dev->sc_sbicp, asr);
   2701 
   2702             if ( asr & SBIC_ASR_INT ) {
   2703                 /*
   2704                  * We need to service a missed IRQ
   2705                  */
   2706                 sbicintr(dev);
   2707             } else {
   2708                 (void) sbicabort(dev, "timeout");
   2709                 splx(s);
   2710                 return;
   2711             }
   2712         }
   2713 
   2714         dev->sc_dmatimo++;
   2715     }
   2716 
   2717     splx(s);
   2718 
   2719     timeout((void *)sbictimeout, dev, 30 * hz);
   2720 }
   2721 #endif
   2722