[unix-history] / usr / sys / dmr / tc.c

#
/*
 *	Copyright 1973 Bell Telephone Laboratories Inc
 */

/*
 * TC-11 DECtape driver
 */

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

struct {
	int	tccsr;
	int	tccm;
	int	tcwc;
	int	tcba;
	int	tcdt;
};

struct	devtab	tctab;

#define	TCADDR	0177340
#define	NTCBLK	578

#define	TAPERR	0100000
#define	TREV	04000
#define	READY	0200
#define	IENABLE	0100
#define	UPS	0200
#define	ENDZ	0100000
#define	BLKM	02000
#define	ILGOP	010000
#define	SELERR	04000

#define	SAT	0
#define	RNUM	02
#define	RDATA	04
#define	SST	010
#define	WDATA	014
#define	GO	01

#define	SFORW	1
#define	SREV	2
#define	SIO	3

tcclose(dev)
{
	bflush(dev);
}

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

	bp = abp;
	if(bp->b_blkno >= NTCBLK) {
		bp->b_flags =| B_ERROR;
		iodone(bp);
		return;
	}
	bp->av_forw = 0;
	spl6();
	if (tctab.d_actf==0)
		tctab.d_actf = bp;
	else
		tctab.d_actl->av_forw = bp;
	tctab.d_actl = bp;
	if (tctab.d_active==0)
		tcstart();
	spl0();
}

tcstart()
{
	register struct buf *bp;
	register int *tccmp, com;

	if ((bp = tctab.d_actf) == 0)
		return;
	tccmp = &TCADDR->tccm;
	if (((*tccmp).hibyte&07) != bp->b_dev.d_minor)
		(*tccmp).lobyte = SAT|GO;
	tctab.d_errcnt = 20;
	tctab.d_active = SFORW;
	com = (bp->b_dev.d_minor<<8) | IENABLE|RNUM|GO;
	if ((TCADDR->tccsr & UPS) == 0) {
		com =| TREV;
		tctab.d_active = SREV;
	}
	*tccmp = com;
}

tcintr()
{
	register struct buf *bp;
	register int *tccmp;
	register int *tcdtp;

	tccmp = &TCADDR->tccm;
	tcdtp = &TCADDR->tccsr;
	bp = tctab.d_actf;
	if (*tccmp&TAPERR) {
		if((*tcdtp & (ENDZ|BLKM)) == 0)
			deverror(bp, *tcdtp);
		if(*tcdtp & (ILGOP|SELERR))
			tctab.d_errcnt = 0;
		*tccmp =& ~TAPERR;
		if (--tctab.d_errcnt  <= 0) {
			bp->b_flags =| B_ERROR;
			goto done;
		}
		if (*tccmp&TREV) {
		setforw:
			tctab.d_active = SFORW;
			*tccmp =& ~TREV;
		} else {
		setback:
			tctab.d_active = SREV;
			*tccmp =| TREV;
		}
		(*tccmp).lobyte = IENABLE|RNUM|GO;
		return;
	}
	tcdtp = &TCADDR->tcdt;
	switch (tctab.d_active) {

	case SIO:
	done:
		tctab.d_active = 0;
		if (tctab.d_actf = bp->av_forw)
			tcstart();
		else
			TCADDR->tccm.lobyte = SAT|GO;
		iodone(bp);
		return;

	case SFORW:
		if (*tcdtp > bp->b_blkno)
			goto setback;
		if (*tcdtp < bp->b_blkno)
			goto setforw;
		*--tcdtp = bp->b_addr;		/* core address */
		*--tcdtp = bp->b_wcount;
		tccmp->lobyte = (bp->b_flags&B_XMEM) | IENABLE|GO
		    | (bp->b_flags&B_READ?RDATA:WDATA);
		tctab.d_active = SIO;
		return;

	case SREV:
		if (*tcdtp+3 > bp->b_blkno)
			goto setback;
		goto setforw;
	}
}
Commit	Line	Data
b74a9dc6 DR	1	#
	2	/*
	3	* Copyright 1973 Bell Telephone Laboratories Inc
	4	*/
	5
	6	/*
	7	* TC-11 DECtape driver
	8	*/
	9
	10	#include "../param.h"
	11	#include "../conf.h"
	12	#include "../buf.h"
	13	#include "../user.h"
	14
	15	struct {
	16	int tccsr;
	17	int tccm;
	18	int tcwc;
	19	int tcba;
	20	int tcdt;
	21	};
	22
	23	struct devtab tctab;
	24
	25	#define TCADDR 0177340
	26	#define NTCBLK 578
	27
	28	#define TAPERR 0100000
	29	#define TREV 04000
	30	#define READY 0200
	31	#define IENABLE 0100
	32	#define UPS 0200
	33	#define ENDZ 0100000
	34	#define BLKM 02000
	35	#define ILGOP 010000
	36	#define SELERR 04000
	37
	38	#define SAT 0
	39	#define RNUM 02
	40	#define RDATA 04
	41	#define SST 010
	42	#define WDATA 014
	43	#define GO 01
	44
	45	#define SFORW 1
	46	#define SREV 2
	47	#define SIO 3
	48
	49	tcclose(dev)
	50	{
	51	bflush(dev);
	52	}
	53
	54	tcstrategy(abp)
	55	struct buf *abp;
	56	{
	57	register struct buf *bp;
	58
	59	bp = abp;
	60	if(bp->b_blkno >= NTCBLK) {
	61	bp->b_flags =\| B_ERROR;
	62	iodone(bp);
	63	return;
	64	}
65	bp->av_forw = 0;
66	spl6();
67	if (tctab.d_actf==0)
68	tctab.d_actf = bp;
69	else
70	tctab.d_actl->av_forw = bp;
71	tctab.d_actl = bp;
72	if (tctab.d_active==0)
73	tcstart();
74	spl0();
75	}
76
77	tcstart()
78	{
79	register struct buf *bp;
80	register int *tccmp, com;
81
82	if ((bp = tctab.d_actf) == 0)
83	return;
84	tccmp = &TCADDR->tccm;
85	if (((*tccmp).hibyte&07) != bp->b_dev.d_minor)
86	(*tccmp).lobyte = SAT\|GO;
87	tctab.d_errcnt = 20;
88	tctab.d_active = SFORW;
89	com = (bp->b_dev.d_minor<<8) \| IENABLE\|RNUM\|GO;
90	if ((TCADDR->tccsr & UPS) == 0) {
91	com =\| TREV;
92	tctab.d_active = SREV;
93	}
94	*tccmp = com;
95	}
96
97	tcintr()
98	{
99	register struct buf *bp;
100	register int *tccmp;
101	register int *tcdtp;
102
103	tccmp = &TCADDR->tccm;
104	tcdtp = &TCADDR->tccsr;
105	bp = tctab.d_actf;
106	if (*tccmp&TAPERR) {
107	if((*tcdtp & (ENDZ\|BLKM)) == 0)
108	deverror(bp, *tcdtp);
109	if(*tcdtp & (ILGOP\|SELERR))
110	tctab.d_errcnt = 0;
111	*tccmp =& ~TAPERR;
112	if (--tctab.d_errcnt <= 0) {
113	bp->b_flags =\| B_ERROR;
114	goto done;
115	}
116	if (*tccmp&TREV) {
117	setforw:
118	tctab.d_active = SFORW;
119	*tccmp =& ~TREV;
120	} else {
121	setback:
122	tctab.d_active = SREV;
123	*tccmp =\| TREV;
124	}
125	(*tccmp).lobyte = IENABLE\|RNUM\|GO;
126	return;
127	}
128	tcdtp = &TCADDR->tcdt;
129	switch (tctab.d_active) {
130
131	case SIO:
132	done:
133	tctab.d_active = 0;
134	if (tctab.d_actf = bp->av_forw)
135	tcstart();
136	else
137	TCADDR->tccm.lobyte = SAT\|GO;
138	iodone(bp);
139	return;
140
141	case SFORW:
142	if (*tcdtp > bp->b_blkno)
143	goto setback;
144	if (*tcdtp < bp->b_blkno)
145	goto setforw;
146	--tcdtp = bp->b_addr; / core address */
147	*--tcdtp = bp->b_wcount;
148	tccmp->lobyte = (bp->b_flags&B_XMEM) \| IENABLE\|GO
149	\| (bp->b_flags&B_READ?RDATA:WDATA);
150	tctab.d_active = SIO;
151	return;
152
153	case SREV:
154	if (*tcdtp+3 > bp->b_blkno)
155	goto setback;
156	goto setforw;
157	}
158	}