Return to dma.c CVS log

Up to [Net/2] / Net2 / arch / amiga / dev

Annotation of Net2/arch/amiga/dev/dma.c, revision 1.1

1.1     ! root        1: /*
        !             2:  * Copyright (c) 1982, 1990 The Regents of the University of California.
        !             3:  * All rights reserved.
        !             4:  *
        !             5:  * Redistribution and use in source and binary forms, with or without
        !             6:  * modification, are permitted provided that the following conditions
        !             7:  * are met:
        !             8:  * 1. Redistributions of source code must retain the above copyright
        !             9:  *    notice, this list of conditions and the following disclaimer.
        !            10:  * 2. Redistributions in binary form must reproduce the above copyright
        !            11:  *    notice, this list of conditions and the following disclaimer in the
        !            12:  *    documentation and/or other materials provided with the distribution.
        !            13:  * 3. All advertising materials mentioning features or use of this software
        !            14:  *    must display the following acknowledgement:
        !            15:  *     This product includes software developed by the University of
        !            16:  *     California, Berkeley and its contributors.
        !            17:  * 4. Neither the name of the University nor the names of its contributors
        !            18:  *    may be used to endorse or promote products derived from this software
        !            19:  *    without specific prior written permission.
        !            20:  *
        !            21:  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
        !            22:  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
        !            23:  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
        !            24:  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
        !            25:  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
        !            26:  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
        !            27:  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
        !            28:  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
        !            29:  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
        !            30:  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
        !            31:  * SUCH DAMAGE.
        !            32:  *
        !            33:  *     @(#)dma.c
        !            34:  */
        !            35: 
        !            36: /*
        !            37:  * DMA driver
        !            38:  */
        !            39: 
        !            40: #include "param.h"
        !            41: #include "systm.h"
        !            42: #include "time.h"
        !            43: #include "kernel.h"
        !            44: #include "proc.h"
        !            45: 
        !            46: #include "vm/vm.h"
        !            47: #include "vm/vm_kern.h"
        !            48: #include "vm/vm_page.h"
        !            49: #include "vm/vm_statistics.h"
        !            50: #include "machine/pmap.h"
        !            51: 
        !            52: #include "device.h"
        !            53: #include "dmareg.h"
        !            54: #include "dmavar.h"
        !            55: 
        !            56: #include "../include/cpu.h"
        !            57: 
        !            58: extern void isrlink();
        !            59: extern void _insque();
        !            60: extern void _remque();
        !            61: extern void timeout();
        !            62: extern u_int kvtop();
        !            63: 
        !            64: /*
        !            65:  * The largest single request will be MAXPHYS bytes which will require
        !            66:  * at most MAXPHYS/NBPG+1 chain elements to describe, i.e. if none of
        !            67:  * the buffer pages are physically contiguous (MAXPHYS/NBPG) and the
        !            68:  * buffer is not page aligned (+1).
        !            69:  */
        !            70: #define        DMAMAXIO        (MAXPHYS/NBPG+1)
        !            71: 
        !            72: struct dma_chain {
        !            73:        int     dc_count;
        !            74:        char    *dc_addr;
        !            75: };
        !            76: 
        !            77: struct dma_softc {
        !            78:        struct  sdmac *sc_hwaddr;
        !            79:        char    sc_dmaflags;
        !            80:        u_short sc_cmd;
        !            81:        struct  dma_chain *sc_cur;
        !            82:        struct  dma_chain *sc_last;
        !            83:        struct  dma_chain sc_chain[DMAMAXIO];
        !            84: } dma_softc;
        !            85: 
        !            86: #define DMAF_NOINTR    0x01
        !            87: 
        !            88: struct devqueue dmachan[NDMA + 1];
        !            89: int    dmaintr();
        !            90: 
        !            91: /* because keybord and dma share same interrupt priority... */
        !            92: int dma_initialized = 0;
        !            93: /* if not in int-mode, don't pay attention for possible scsi interrupts */
        !            94: int scsi_int_mode = 0;
        !            95: 
        !            96: #ifdef DEBUG
        !            97: #define        DDB_FOLLOW      0x04
        !            98: #define DDB_IO         0x08
        !            99: int    dmadebug = 0;
        !           100: 
        !           101: void   dmatimeout();
        !           102: int    dmatimo;
        !           103: 
        !           104: long   dmahits;
        !           105: long   dmamisses;
        !           106: long   dmabyte;
        !           107: long   dmaword;
        !           108: long   dmalword;
        !           109: #endif
        !           110: 
        !           111: /* This setup function is also used by the SCSI driver, as it shares
        !           112:    the same chip */
        !           113: 
        !           114: struct sdmac *SDMAC_address = 0;
        !           115: volatile void *SCSI_address = 0;
        !           116: 
        !           117: void 
        !           118: SDMAC_setup ()
        !           119: {
        !           120:   if (! SDMAC_address)
        !           121:     {
        !           122:       extern u_int SCSIADDR;   /* setup in amiga_init.c. Should really be mapped here... */
        !           123:       SDMAC_address = (struct sdmac *) SCSIADDR;
        !           124:       SCSI_address = &SDMAC_address->SASR;
        !           125:     }
        !           126: }
        !           127: 
        !           128: 
        !           129: void
        !           130: dmainit()
        !           131: {
        !           132:   register struct sdmac *dma;
        !           133:   register int i;
        !           134:   char rev;
        !           135: 
        !           136:   SDMAC_setup ();
        !           137:   dma = SDMAC_address;
        !           138: 
        !           139:   /* make sure interrupts are disabled while we later on reset the scsi-chip */
        !           140:   dma->CNTR = CNTR_PDMD;
        !           141:   dma->DAWR = DAWR_A3000;
        !           142:   dma_softc.sc_dmaflags = 0;
        !           143:   dma_softc.sc_cmd = 0;
        !           144:   dma_softc.sc_hwaddr = dma;
        !           145:   dmachan[0].dq_forw = dmachan[0].dq_back = &dmachan[0];
        !           146:   dmachan[1].dq_forw = dmachan[1].dq_back = &dmachan[1];
        !           147: #ifdef DEBUG
        !           148:   /* make sure timeout is really not needed */
        !           149:   timeout(dmatimeout, 0, 30 * hz);
        !           150: #endif
        !           151: 
        !           152:   printf("dma: A3000 %d bit DMA\n", 32);       /* XXX */
        !           153:   dma_initialized = 1;
        !           154: }
        !           155: 
        !           156: int
        !           157: dmareq(dq)
        !           158:        register struct devqueue *dq;
        !           159: {
        !           160:   register int s = splbio();
        !           161: 
        !           162:   if (dmachan[0].dq_forw == &dmachan[0])
        !           163:     {
        !           164:       insque(dq, &dmachan[0]);
        !           165:       dq->dq_ctlr = 0;
        !           166:       splx(s);
        !           167:       return 1;
        !           168:     }
        !           169: 
        !           170:   insque (dq, dmachan[1].dq_back);
        !           171:   splx(s);
        !           172:   return(0);
        !           173: }
        !           174: 
        !           175: void
        !           176: dmafree(dq)
        !           177:        register struct devqueue *dq;
        !           178: {
        !           179:   register struct dma_softc *dc = &dma_softc;
        !           180:   register struct devqueue *dn;
        !           181:   register int s;
        !           182: 
        !           183:   s = splbio();
        !           184: #ifdef DEBUG
        !           185:   dmatimo = 0;
        !           186: #endif
        !           187:   if (dc->sc_cmd)
        !           188:     {
        !           189:       if ((dc->sc_cmd & (CNTR_TCEN | CNTR_DDIR)) == 0)
        !           190:         {
        !           191:           /* only FLUSH if terminal count not enabled, and reading from peripheral */
        !           192:           dc->sc_hwaddr->FLUSH = 1;
        !           193:           while (! (dc->sc_hwaddr->ISTR & ISTR_FE_FLG)) ;
        !           194:         }
        !           195:       dc->sc_hwaddr->CINT = 1;         /* clear possible interrupt */
        !           196:       dc->sc_hwaddr->SP_DMA = 1;       /* stop dma */
        !           197:       dc->sc_cmd = 0;
        !           198:     }
        !           199:   dc->sc_hwaddr->CNTR = CNTR_PDMD;     /* disable interrupts from dma/scsi */
        !           200:   scsi_int_mode = 0;
        !           201: 
        !           202:   remque(dq);
        !           203:   for (dn = dmachan[1].dq_forw;
        !           204:        dn != &dmachan[1]; 
        !           205:        dn = dn->dq_forw) 
        !           206:     {
        !           207:       remque ((caddr_t) dn);
        !           208:       insque ((caddr_t) dn, (caddr_t) dq->dq_back);
        !           209:       splx(s);
        !           210:       dn->dq_ctlr = dq->dq_ctlr;
        !           211:       (dn->dq_driver->d_start)(0);
        !           212:       return;
        !           213:     }
        !           214: 
        !           215:   splx(s);
        !           216: }
        !           217: 
        !           218: int
        !           219: dmago(addr, count, flags)
        !           220:        register char *addr;
        !           221:        register int count;
        !           222:        register int flags;
        !           223: {
        !           224:   register struct dma_softc *dc = &dma_softc;
        !           225:   register struct dma_chain *dcp;
        !           226:   register char *dmaend = NULL;
        !           227:   register int tcount;
        !           228: 
        !           229:   if (count > MAXPHYS)
        !           230:      panic("dmago: count > MAXPHYS");
        !           231: #ifdef DEBUG
        !           232:   if (dmadebug & DDB_FOLLOW)
        !           233:      printf("dmago(%x, %x, %x)\n", addr, count, flags);
        !           234: #endif
        !           235:   /*
        !           236:    * Build the DMA chain
        !           237:    */
        !           238:   for (dcp = dc->sc_chain; count > 0; dcp++) 
        !           239:     {
        !           240: #ifdef DEBUG
        !           241:       if (! pmap_extract(pmap_kernel(), (vm_offset_t)addr))
        !           242:         panic ("dmago: no physical page for address!");
        !           243: #endif
        !           244: 
        !           245:       dcp->dc_addr = (char *) kvtop(addr);
        !           246:       if (count < (tcount = NBPG - ((int)addr & PGOFSET)))
        !           247:        tcount = count;
        !           248:       dcp->dc_count = tcount;
        !           249:       addr += tcount;
        !           250:       count -= tcount;
        !           251:       tcount >>= 1;    /* number of words (the sdmac wants 16bit values here) */
        !           252:       if (dcp->dc_addr == dmaend) 
        !           253:        {
        !           254: #ifdef DEBUG
        !           255:          dmahits++;
        !           256: #endif
        !           257:          dmaend += dcp->dc_count;
        !           258:          (--dcp)->dc_count += tcount;
        !           259:        } 
        !           260:       else 
        !           261:         {
        !           262: #ifdef DEBUG
        !           263:          dmamisses++;
        !           264: #endif
        !           265:          dmaend = dcp->dc_addr + dcp->dc_count;
        !           266:          dcp->dc_count = tcount;
        !           267:        }
        !           268:     }
        !           269: 
        !           270:   dc->sc_cur = dc->sc_chain;
        !           271:   dc->sc_last = --dcp;
        !           272:   dc->sc_dmaflags = 0;
        !           273:   /*
        !           274:    * Set up the command word based on flags
        !           275:    */
        !           276:   dc->sc_cmd = CNTR_PDMD | CNTR_INTEN;
        !           277:   if ((flags & DMAGO_READ) == 0)
        !           278:     dc->sc_cmd |= CNTR_DDIR;
        !           279: #ifdef DEBUG
        !           280:   if (dmadebug & DDB_IO)
        !           281:     {
        !           282:       printf("dmago: cmd %x, flags %x\n",
        !           283:             dc->sc_cmd, dc->sc_dmaflags);
        !           284:       for (dcp = dc->sc_chain; dcp <= dc->sc_last; dcp++)
        !           285:        printf("  %d: %d@%x\n", dcp-dc->sc_chain,
        !           286:               dcp->dc_count, dcp->dc_addr);
        !           287:     }
        !           288:   dmatimo = 1;
        !           289: #endif
        !           290: 
        !           291:   dc->sc_hwaddr->CNTR = dc->sc_cmd;
        !           292:   scsi_int_mode = 1;
        !           293:   dc->sc_hwaddr->ACR = (u_int) dc->sc_cur->dc_addr;
        !           294:   dc->sc_hwaddr->ST_DMA = 1;
        !           295:   
        !           296:   return dc->sc_cur->dc_count << 1;
        !           297: }
        !           298: 
        !           299: void
        !           300: dmastop()
        !           301: {
        !           302:   register struct dma_softc *dc = &dma_softc;
        !           303:   register struct devqueue *dq;
        !           304:   int s;
        !           305: 
        !           306: #ifdef DEBUG
        !           307:   if (dmadebug & DDB_FOLLOW)
        !           308:     printf("dmastop()\n");
        !           309:   dmatimo = 0;
        !           310: #endif
        !           311:   if (dc->sc_cmd)
        !           312:     {
        !           313:       s = splbio ();
        !           314:       if ((dc->sc_cmd & (CNTR_TCEN | CNTR_DDIR)) == 0)
        !           315:         {
        !           316:           /* only FLUSH if terminal count not enabled, and reading from peripheral */
        !           317:          dc->sc_hwaddr->FLUSH = 1;
        !           318:           while (! (dc->sc_hwaddr->ISTR & ISTR_FE_FLG)) ;
        !           319:         }
        !           320:       dc->sc_hwaddr->CINT = 1;         /* clear possible interrupt */
        !           321:       dc->sc_hwaddr->SP_DMA = 1;       /* stop dma */
        !           322:       dc->sc_cmd = 0;
        !           323:       splx (s);
        !           324:     }
        !           325: 
        !           326:   /*
        !           327:    * We may get this interrupt after a device service routine
        !           328:    * has freed the dma channel.  So, ignore the intr if there's
        !           329:    * nothing on the queue.
        !           330:    */
        !           331:   dq = dmachan[0].dq_forw;
        !           332:   if (dq != &dmachan[0])
        !           333:     (dq->dq_driver->d_done)(0);
        !           334: }
        !           335: 
        !           336: int
        !           337: dmaintr()
        !           338: {
        !           339:   register struct dma_softc *dc;
        !           340:   register int i, stat;
        !           341:   int found = 0;
        !           342: 
        !           343:   if (! dma_initialized)
        !           344:     return 0;
        !           345: 
        !           346:   dc = &dma_softc;
        !           347:   stat = dc->sc_hwaddr->ISTR;
        !           348: 
        !           349:   /* if no interrupt from this device, return quickly */
        !           350:   if (! (stat & (ISTR_INT_F|ISTR_INT_P)))
        !           351:     return 0;
        !           352:   
        !           353: #ifdef DEBUG
        !           354:   if (dmadebug & DDB_FOLLOW)
        !           355:      printf("dmaintr (0x%x)\n", stat);
        !           356: #endif
        !           357: 
        !           358:   /* both, SCSI and DMA interrupts arrive here. I chose arbitrarily that
        !           359:      DMA interrupts should have higher precedence than SCSI interrupts. */
        !           360: 
        !           361:   if (stat & ISTR_E_INT)
        !           362:     {
        !           363:       found++;
        !           364: 
        !           365: printf ("DMAINTR should no longer be entered!!\n");
        !           366: 
        !           367: 
        !           368:       /* End-of-process interrupt, means the DMA Terminal Counter reached
        !           369:          0, and we have to reload it. SCSI transfer should not be interrupted
        !           370:          by this event (we'll see..) */
        !           371: 
        !           372: #ifdef DEBUG
        !           373:       if (dmadebug & DDB_IO) 
        !           374:        {
        !           375:          printf("dmaintr: stat %x next %d\n",
        !           376:                 stat, (dc->sc_cur-dc->sc_chain)+1);
        !           377:        }
        !           378: #endif
        !           379:       if (++dc->sc_cur <= dc->sc_last) 
        !           380:        {
        !           381: #ifdef DEBUG
        !           382:          dmatimo = 1;
        !           383: #endif
        !           384:          /*
        !           385:           * Last chain segment, disable DMA interrupt.
        !           386:           */
        !           387:          if (dc->sc_cur == dc->sc_last && (dc->sc_dmaflags & DMAF_NOINTR))
        !           388:            dc->sc_cmd &= ~CNTR_TCEN;
        !           389: 
        !           390:          dc->sc_hwaddr->CINT = 1;              /* clear possible interrupt */
        !           391:          dc->sc_hwaddr->CNTR = dc->sc_cmd;
        !           392:          dc->sc_hwaddr->ACR = (u_int) dc->sc_cur->dc_addr;
        !           393: #ifndef DONT_WTC
        !           394:          if (dc->sc_cmd & CNTR_TCEN)
        !           395:            dc->sc_hwaddr->WTC = dc->sc_cur->dc_count;
        !           396: #endif
        !           397:          dc->sc_hwaddr->ST_DMA = 1;
        !           398:        } 
        !           399:       else
        !           400:        dmastop ();
        !           401:        
        !           402:       /* check for SCSI ints in the same go and eventually save an interrupt */
        !           403:     }
        !           404: 
        !           405:   if (scsi_int_mode && (stat & ISTR_INTS))
        !           406:     return found + scsiintr (0);
        !           407: 
        !           408:   return found;
        !           409: }
        !           410: 
        !           411: 
        !           412: int
        !           413: dmanext ()
        !           414: {
        !           415:   register struct dma_softc *dc;
        !           416:   register int i, stat;
        !           417:   int found = 0;
        !           418: 
        !           419:   dc = &dma_softc;
        !           420: 
        !           421: #ifdef DEBUG
        !           422:   if (dmadebug & DDB_IO) 
        !           423:     {
        !           424:       printf("dmanext: next %d\n", (dc->sc_cur-dc->sc_chain)+1);
        !           425:     }
        !           426: #endif
        !           427:   if (++dc->sc_cur <= dc->sc_last) 
        !           428:     {
        !           429: #ifdef DEBUG
        !           430:       dmatimo = 1;
        !           431: #endif
        !           432:       if ((dc->sc_cmd & (CNTR_TCEN | CNTR_DDIR)) == 0)
        !           433:         {
        !           434:           /* only FLUSH if terminal count not enabled, and reading from peripheral */
        !           435:           dc->sc_hwaddr->FLUSH = 1;
        !           436:           while (! (dc->sc_hwaddr->ISTR & ISTR_FE_FLG)) ;
        !           437:         }
        !           438:       dc->sc_hwaddr->CINT = 1;         /* clear possible interrupt */
        !           439:       dc->sc_hwaddr->SP_DMA = 1;       /* stop dma */
        !           440:       dc->sc_hwaddr->CNTR = dc->sc_cmd;
        !           441:       dc->sc_hwaddr->ACR = (u_int) dc->sc_cur->dc_addr;
        !           442:       dc->sc_hwaddr->ST_DMA = 1;
        !           443:       
        !           444:       return dc->sc_cur->dc_count << 1;
        !           445:     } 
        !           446:   else
        !           447:     {
        !           448:       /* shouldn't happen !! */
        !           449:       printf ("dmanext at end !!!\n");
        !           450:       dmastop ();
        !           451:       return 0;
        !           452:     }
        !           453: }
        !           454: 
        !           455: 
        !           456: 
        !           457: 
        !           458: #ifdef DEBUG
        !           459: void
        !           460: dmatimeout()
        !           461: {
        !           462:   register int s;
        !           463: 
        !           464:   s = splbio();
        !           465:   if (dmatimo) 
        !           466:     {
        !           467:       if (dmatimo > 1)
        !           468:        printf("dma: timeout #%d\n", dmatimo-1);
        !           469:       dmatimo++;
        !           470:     }
        !           471:   splx(s);
        !           472:   timeout (dmatimeout, (caddr_t)0, 30 * hz);
        !           473: }
        !           474: #endif

This archive runs on limited infrastructure. Preserving old code on modern bandwidth. Automated agents are requested to crawl responsibly.