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[unix-history] / sys / dmr / rf.c

#
/*
* RF disk driver
*/

#include "/sys/nsys/param.h"
#include "/sys/nsys/buf.h"
#include "/sys/nsys/conf.h"
#include "/sys/nsys/user.h"

struct { char lbyte, hbyte; };

struct {
       int     rfcs;
       int     rfwc;
       int     rfba;
       int     rfda;
       int     rfdae;
};

#define NRFBLK  2048
#define RFADDR  0177460
#define JRF     0

#define GO      01
#define RCOM    02
#define WCOM    04
#define IENABLE 0100

rfstrategy(abp)
struct buf *abp;
{
       register struct buf *bp;

       bp = abp;
       if (bp->b_blkno >= NRFBLK) {
               bp->b_flags =| B_ERROR;
               iodone(bp);
               return;
       }
       bp->av_forw = 0;
       spl5();
       if (devtab[JRF].d_actf==0)
               devtab[JRF].d_actf = bp;
       else
               devtab[JRF].d_actl->av_forw = bp;
       devtab[JRF].d_actl = bp;
       if (devtab[JRF].d_active==0)
               rfstart();
       spl0();
}

rfstart()
{
       register struct buf *bp;

       if ((bp = devtab[JRF].d_actf) == 0)
               return;
       devtab[JRF].d_active++;
       RFADDR->rfdae = bp->b_blkno.hbyte;
       devstart(bp, &RFADDR->rfda, bp->b_blkno<<8);
}

rfintr()
{
       register struct buf *bp;

       if (devtab[JRF].d_active == 0)
               return;
       bp = devtab[JRF].d_actf;
       devtab[JRF].d_active = 0;
       if (RFADDR->rfcs < 0) {         /* error bit */
               if (++devtab[JRF].d_errcnt <= 10) {
                       rfstart();
                       return;
               }
               bp->b_flags =| B_ERROR;
       }
       devtab[JRF].d_errcnt = 0;
       devtab[JRF].d_actf = bp->av_forw;
       iodone(bp);
       rfstart();
}