xref: /original-bsd/sys/pmax/dev/dc.c (revision bacd16ee)
1 /*-
2  * Copyright (c) 1992, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * This code is derived from software contributed to Berkeley by
6  * Ralph Campbell and Rick Macklem.
7  *
8  * %sccs.include.redist.c%
9  *
10  *	@(#)dc.c	8.1 (Berkeley) 06/10/93
11  */
12 
13 /*
14  * devDC7085.c --
15  *
16  *     	This file contains machine-dependent routines that handle the
17  *	output queue for the serial lines.
18  *
19  *	Copyright (C) 1989 Digital Equipment Corporation.
20  *	Permission to use, copy, modify, and distribute this software and
21  *	its documentation for any purpose and without fee is hereby granted,
22  *	provided that the above copyright notice appears in all copies.
23  *	Digital Equipment Corporation makes no representations about the
24  *	suitability of this software for any purpose.  It is provided "as is"
25  *	without express or implied warranty.
26  *
27  * from: $Header: /sprite/src/kernel/dev/ds3100.md/RCS/devDC7085.c,
28  *	v 1.4 89/08/29 11:55:30 nelson Exp $ SPRITE (DECWRL)";
29  */
30 
31 #include <dc.h>
32 #if NDC > 0
33 /*
34  * DC7085 (DZ-11 look alike) Driver
35  */
36 #include <sys/param.h>
37 #include <sys/systm.h>
38 #include <sys/ioctl.h>
39 #include <sys/tty.h>
40 #include <sys/proc.h>
41 #include <sys/map.h>
42 #include <sys/buf.h>
43 #include <sys/conf.h>
44 #include <sys/file.h>
45 #include <sys/uio.h>
46 #include <sys/kernel.h>
47 #include <sys/syslog.h>
48 
49 #include <machine/dc7085cons.h>
50 #include <machine/pmioctl.h>
51 
52 #include <pmax/pmax/pmaxtype.h>
53 #include <pmax/pmax/cons.h>
54 
55 #include <pmax/dev/device.h>
56 #include <pmax/dev/pdma.h>
57 #include <pmax/dev/fbreg.h>
58 
59 extern int pmax_boardtype;
60 extern struct consdev cn_tab;
61 
62 /*
63  * Driver information for auto-configuration stuff.
64  */
65 int	dcprobe();
66 void	dcintr();
67 struct	driver dcdriver = {
68 	"dc", dcprobe, 0, 0, dcintr,
69 };
70 
71 #define	NDCLINE 	(NDC*4)
72 
73 void dcstart	__P((struct tty *));
74 void dcxint	__P((struct tty *));
75 void dcPutc	__P((dev_t, int));
76 void dcscan	__P((void *));
77 extern void ttrstrt __P((void *));
78 int dcGetc	__P((dev_t));
79 int dcparam	__P((struct tty *, struct termios *));
80 
81 struct	tty dc_tty[NDCLINE];
82 int	dc_cnt = NDCLINE;
83 void	(*dcDivertXInput)();	/* X windows keyboard input routine */
84 void	(*dcMouseEvent)();	/* X windows mouse motion event routine */
85 void	(*dcMouseButtons)();	/* X windows mouse buttons event routine */
86 #ifdef DEBUG
87 int	debugChar;
88 #endif
89 
90 /*
91  * Software copy of brk register since it isn't readable
92  */
93 int	dc_brk[NDC];
94 char	dcsoftCAR[NDC];		/* mask of dc's with carrier on (DSR) */
95 
96 /*
97  * The DC7085 doesn't interrupt on carrier transitions, so
98  * we have to use a timer to watch it.
99  */
100 int	dc_timer;		/* true if timer started */
101 
102 /*
103  * Pdma structures for fast output code
104  */
105 struct	pdma dcpdma[NDCLINE];
106 
107 struct speedtab dcspeedtab[] = {
108 	0,	0,
109 	50,	LPR_B50,
110 	75,	LPR_B75,
111 	110,	LPR_B110,
112 	134,	LPR_B134,
113 	150,	LPR_B150,
114 	300,	LPR_B300,
115 	600,	LPR_B600,
116 	1200,	LPR_B1200,
117 	1800,	LPR_B1800,
118 	2400,	LPR_B2400,
119 	4800,	LPR_B4800,
120 	9600,	LPR_B9600,
121 	19200,	LPR_B19200,
122 	-1,	-1
123 };
124 
125 #ifndef	PORTSELECTOR
126 #define	ISPEED	TTYDEF_SPEED
127 #define	LFLAG	TTYDEF_LFLAG
128 #else
129 #define	ISPEED	B4800
130 #define	LFLAG	(TTYDEF_LFLAG & ~ECHO)
131 #endif
132 
133 /*
134  * Test to see if device is present.
135  * Return true if found and initialized ok.
136  */
137 dcprobe(cp)
138 	register struct pmax_ctlr *cp;
139 {
140 	register dcregs *dcaddr;
141 	register struct pdma *pdp;
142 	register struct tty *tp;
143 	register int cntr;
144 	int s;
145 
146 	if (cp->pmax_unit >= NDC)
147 		return (0);
148 	if (badaddr(cp->pmax_addr, 2))
149 		return (0);
150 
151 	/*
152 	 * For a remote console, wait a while for previous output to
153 	 * complete.
154 	 */
155 	if (major(cn_tab.cn_dev) == DCDEV && cp->pmax_unit == 0 &&
156 		cn_tab.cn_screen == 0)
157 		DELAY(10000);
158 
159 	/* reset chip */
160 	dcaddr = (dcregs *)cp->pmax_addr;
161 	dcaddr->dc_csr = CSR_CLR;
162 	MachEmptyWriteBuffer();
163 	while (dcaddr->dc_csr & CSR_CLR)
164 		;
165 	dcaddr->dc_csr = CSR_MSE | CSR_TIE | CSR_RIE;
166 
167 	/* init pseudo DMA structures */
168 	pdp = &dcpdma[cp->pmax_unit * 4];
169 	tp = &dc_tty[cp->pmax_unit * 4];
170 	for (cntr = 0; cntr < 4; cntr++) {
171 		pdp->p_addr = (void *)dcaddr;
172 		pdp->p_arg = (int)tp;
173 		pdp->p_fcn = dcxint;
174 		tp->t_addr = (caddr_t)pdp;
175 		pdp++, tp++;
176 	}
177 	dcsoftCAR[cp->pmax_unit] = cp->pmax_flags | 0xB;
178 
179 	if (dc_timer == 0) {
180 		dc_timer = 1;
181 		timeout(dcscan, (void *)0, hz);
182 	}
183 
184 	/*
185 	 * Special handling for consoles.
186 	 */
187 	if (cp->pmax_unit == 0) {
188 		if (cn_tab.cn_screen) {
189 			s = spltty();
190 			dcaddr->dc_lpr = LPR_RXENAB | LPR_8_BIT_CHAR |
191 				LPR_B4800 | DCKBD_PORT;
192 			MachEmptyWriteBuffer();
193 			dcaddr->dc_lpr = LPR_RXENAB | LPR_B4800 | LPR_OPAR |
194 				LPR_PARENB | LPR_8_BIT_CHAR | DCMOUSE_PORT;
195 			MachEmptyWriteBuffer();
196 			DELAY(1000);
197 			KBDReset(makedev(DCDEV, DCKBD_PORT), dcPutc);
198 			MouseInit(makedev(DCDEV, DCMOUSE_PORT), dcPutc, dcGetc);
199 			splx(s);
200 		} else if (major(cn_tab.cn_dev) == DCDEV) {
201 			s = spltty();
202 			dcaddr->dc_lpr = LPR_RXENAB | LPR_8_BIT_CHAR |
203 				LPR_B9600 | minor(cn_tab.cn_dev);
204 			MachEmptyWriteBuffer();
205 			DELAY(1000);
206 			cn_tab.cn_disabled = 0;
207 			splx(s);
208 		}
209 	}
210 	printf("dc%d at nexus0 csr 0x%x priority %d\n",
211 		cp->pmax_unit, cp->pmax_addr, cp->pmax_pri);
212 	return (1);
213 }
214 
215 dcopen(dev, flag, mode, p)
216 	dev_t dev;
217 	int flag, mode;
218 	struct proc *p;
219 {
220 	register struct tty *tp;
221 	register int unit;
222 	int s, error = 0;
223 
224 	unit = minor(dev);
225 	if (unit >= dc_cnt || dcpdma[unit].p_addr == (void *)0)
226 		return (ENXIO);
227 	tp = &dc_tty[unit];
228 	tp->t_addr = (caddr_t)&dcpdma[unit];
229 	tp->t_oproc = dcstart;
230 	tp->t_param = dcparam;
231 	tp->t_dev = dev;
232 	if ((tp->t_state & TS_ISOPEN) == 0) {
233 		tp->t_state |= TS_WOPEN;
234 		ttychars(tp);
235 #ifndef PORTSELECTOR
236 		if (tp->t_ispeed == 0) {
237 #endif
238 			tp->t_iflag = TTYDEF_IFLAG;
239 			tp->t_oflag = TTYDEF_OFLAG;
240 			tp->t_cflag = TTYDEF_CFLAG;
241 			tp->t_lflag = LFLAG;
242 			tp->t_ispeed = tp->t_ospeed = ISPEED;
243 #ifdef PORTSELECTOR
244 			tp->t_cflag |= HUPCL;
245 #else
246 		}
247 #endif
248 		(void) dcparam(tp, &tp->t_termios);
249 		ttsetwater(tp);
250 	} else if ((tp->t_state & TS_XCLUDE) && curproc->p_ucred->cr_uid != 0)
251 		return (EBUSY);
252 	(void) dcmctl(dev, DML_DTR, DMSET);
253 	s = spltty();
254 	while (!(flag & O_NONBLOCK) && !(tp->t_cflag & CLOCAL) &&
255 	       !(tp->t_state & TS_CARR_ON)) {
256 		tp->t_state |= TS_WOPEN;
257 		if (error = ttysleep(tp, (caddr_t)&tp->t_rawq, TTIPRI | PCATCH,
258 		    ttopen, 0))
259 			break;
260 	}
261 	splx(s);
262 	if (error)
263 		return (error);
264 	return ((*linesw[tp->t_line].l_open)(dev, tp));
265 }
266 
267 /*ARGSUSED*/
268 dcclose(dev, flag, mode, p)
269 	dev_t dev;
270 	int flag, mode;
271 	struct proc *p;
272 {
273 	register struct tty *tp;
274 	register int unit, bit;
275 
276 	unit = minor(dev);
277 	tp = &dc_tty[unit];
278 	bit = 1 << ((unit & 03) + 8);
279 	if (dc_brk[unit >> 2] & bit) {
280 		dc_brk[unit >> 2] &= ~bit;
281 		ttyoutput(0, tp);
282 	}
283 	(*linesw[tp->t_line].l_close)(tp, flag);
284 	if ((tp->t_cflag & HUPCL) || (tp->t_state & TS_WOPEN) ||
285 	    !(tp->t_state & TS_ISOPEN))
286 		(void) dcmctl(dev, 0, DMSET);
287 	return (ttyclose(tp));
288 }
289 
290 dcread(dev, uio, flag)
291 	dev_t dev;
292 	struct uio *uio;
293 {
294 	register struct tty *tp;
295 
296 	tp = &dc_tty[minor(dev)];
297 	return ((*linesw[tp->t_line].l_read)(tp, uio, flag));
298 }
299 
300 dcwrite(dev, uio, flag)
301 	dev_t dev;
302 	struct uio *uio;
303 {
304 	register struct tty *tp;
305 
306 	tp = &dc_tty[minor(dev)];
307 	return ((*linesw[tp->t_line].l_write)(tp, uio, flag));
308 }
309 
310 /*ARGSUSED*/
311 dcioctl(dev, cmd, data, flag, p)
312 	dev_t dev;
313 	int cmd;
314 	caddr_t data;
315 	int flag;
316 	struct proc *p;
317 {
318 	register struct tty *tp;
319 	register int unit = minor(dev);
320 	register int dc = unit >> 2;
321 	int error;
322 
323 	tp = &dc_tty[unit];
324 	error = (*linesw[tp->t_line].l_ioctl)(tp, cmd, data, flag, p);
325 	if (error >= 0)
326 		return (error);
327 	error = ttioctl(tp, cmd, data, flag);
328 	if (error >= 0)
329 		return (error);
330 
331 	switch (cmd) {
332 
333 	case TIOCSBRK:
334 		dc_brk[dc] |= 1 << ((unit & 03) + 8);
335 		ttyoutput(0, tp);
336 		break;
337 
338 	case TIOCCBRK:
339 		dc_brk[dc] &= ~(1 << ((unit & 03) + 8));
340 		ttyoutput(0, tp);
341 		break;
342 
343 	case TIOCSDTR:
344 		(void) dcmctl(dev, DML_DTR|DML_RTS, DMBIS);
345 		break;
346 
347 	case TIOCCDTR:
348 		(void) dcmctl(dev, DML_DTR|DML_RTS, DMBIC);
349 		break;
350 
351 	case TIOCMSET:
352 		(void) dcmctl(dev, *(int *)data, DMSET);
353 		break;
354 
355 	case TIOCMBIS:
356 		(void) dcmctl(dev, *(int *)data, DMBIS);
357 		break;
358 
359 	case TIOCMBIC:
360 		(void) dcmctl(dev, *(int *)data, DMBIC);
361 		break;
362 
363 	case TIOCMGET:
364 		*(int *)data = dcmctl(dev, 0, DMGET);
365 		break;
366 
367 	default:
368 		return (ENOTTY);
369 	}
370 	return (0);
371 }
372 
373 dcparam(tp, t)
374 	register struct tty *tp;
375 	register struct termios *t;
376 {
377 	register dcregs *dcaddr;
378 	register int lpr;
379 	register int cflag = t->c_cflag;
380 	int unit = minor(tp->t_dev);
381 	int ospeed = ttspeedtab(t->c_ospeed, dcspeedtab);
382 
383 	/* check requested parameters */
384         if (ospeed < 0 || (t->c_ispeed && t->c_ispeed != t->c_ospeed) ||
385             (cflag & CSIZE) == CS5 || (cflag & CSIZE) == CS6 ||
386 	    (pmax_boardtype == DS_PMAX && t->c_ospeed == 19200))
387                 return (EINVAL);
388         /* and copy to tty */
389         tp->t_ispeed = t->c_ispeed;
390         tp->t_ospeed = t->c_ospeed;
391         tp->t_cflag = cflag;
392 
393 	dcaddr = (dcregs *)dcpdma[unit].p_addr;
394 
395 	/*
396 	 * Handle console cases specially.
397 	 */
398 	if (cn_tab.cn_screen) {
399 		if (unit == DCKBD_PORT) {
400 			dcaddr->dc_lpr = LPR_RXENAB | LPR_8_BIT_CHAR |
401 				LPR_B4800 | DCKBD_PORT;
402 			MachEmptyWriteBuffer();
403 			return (0);
404 		} else if (unit == DCMOUSE_PORT) {
405 			dcaddr->dc_lpr = LPR_RXENAB | LPR_B4800 | LPR_OPAR |
406 				LPR_PARENB | LPR_8_BIT_CHAR | DCMOUSE_PORT;
407 			MachEmptyWriteBuffer();
408 			return (0);
409 		}
410 	} else if (tp->t_dev == cn_tab.cn_dev) {
411 		dcaddr->dc_lpr = LPR_RXENAB | LPR_8_BIT_CHAR |
412 			LPR_B9600 | unit;
413 		MachEmptyWriteBuffer();
414 		return (0);
415 	}
416 	if (ospeed == 0) {
417 		(void) dcmctl(unit, 0, DMSET);	/* hang up line */
418 		return (0);
419 	}
420 	lpr = LPR_RXENAB | ospeed | (unit & 03);
421 	if ((cflag & CSIZE) == CS7)
422 		lpr |= LPR_7_BIT_CHAR;
423 	else
424 		lpr |= LPR_8_BIT_CHAR;
425 	if (cflag & PARENB)
426 		lpr |= LPR_PARENB;
427 	if (cflag & PARODD)
428 		lpr |= LPR_OPAR;
429 	if (cflag & CSTOPB)
430 		lpr |= LPR_2_STOP;
431 	dcaddr->dc_lpr = lpr;
432 	MachEmptyWriteBuffer();
433 	DELAY(10);
434 	return (0);
435 }
436 
437 /*
438  * Check for interrupts from all devices.
439  */
440 void
441 dcintr(unit)
442 	register int unit;
443 {
444 	register dcregs *dcaddr;
445 	register unsigned csr;
446 
447 	unit <<= 2;
448 	dcaddr = (dcregs *)dcpdma[unit].p_addr;
449 	while ((csr = dcaddr->dc_csr) & (CSR_RDONE | CSR_TRDY)) {
450 		if (csr & CSR_RDONE)
451 			dcrint(unit);
452 		if (csr & CSR_TRDY)
453 			dcxint(&dc_tty[unit + ((csr >> 8) & 03)]);
454 	}
455 }
456 
457 dcrint(unit)
458 	register int unit;
459 {
460 	register dcregs *dcaddr;
461 	register struct tty *tp;
462 	register int c, cc;
463 	register struct tty *tp0;
464 	int overrun = 0;
465 
466 	dcaddr = (dcregs *)dcpdma[unit].p_addr;
467 	tp0 = &dc_tty[unit];
468 	while ((c = dcaddr->dc_rbuf) < 0) {	/* char present */
469 		cc = c & 0xff;
470 		tp = tp0 + ((c >> 8) & 03);
471 		if ((c & RBUF_OERR) && overrun == 0) {
472 			log(LOG_WARNING, "dc%d,%d: silo overflow\n", unit >> 2,
473 				(c >> 8) & 03);
474 			overrun = 1;
475 		}
476 		/* the keyboard requires special translation */
477 		if (tp == &dc_tty[DCKBD_PORT] && cn_tab.cn_screen) {
478 #ifdef KADB
479 			if (cc == LK_DO) {
480 				spl0();
481 				kdbpanic();
482 				return;
483 			}
484 #endif
485 #ifdef DEBUG
486 			debugChar = cc;
487 #endif
488 			if (dcDivertXInput) {
489 				(*dcDivertXInput)(cc);
490 				return;
491 			}
492 			if ((cc = kbdMapChar(cc)) < 0)
493 				return;
494 		} else if (tp == &dc_tty[DCMOUSE_PORT] && dcMouseButtons) {
495 			register MouseReport *mrp;
496 			static MouseReport currentRep;
497 
498 			mrp = &currentRep;
499 			mrp->byteCount++;
500 			if (cc & MOUSE_START_FRAME) {
501 				/*
502 				 * The first mouse report byte (button state).
503 				 */
504 				mrp->state = cc;
505 				if (mrp->byteCount > 1)
506 					mrp->byteCount = 1;
507 			} else if (mrp->byteCount == 2) {
508 				/*
509 				 * The second mouse report byte (delta x).
510 				 */
511 				mrp->dx = cc;
512 			} else if (mrp->byteCount == 3) {
513 				/*
514 				 * The final mouse report byte (delta y).
515 				 */
516 				mrp->dy = cc;
517 				mrp->byteCount = 0;
518 				if (mrp->dx != 0 || mrp->dy != 0) {
519 					/*
520 					 * If the mouse moved,
521 					 * post a motion event.
522 					 */
523 					(*dcMouseEvent)(mrp);
524 				}
525 				(*dcMouseButtons)(mrp);
526 			}
527 			return;
528 		}
529 		if (!(tp->t_state & TS_ISOPEN)) {
530 			wakeup((caddr_t)&tp->t_rawq);
531 #ifdef PORTSELECTOR
532 			if (!(tp->t_state & TS_WOPEN))
533 #endif
534 				return;
535 		}
536 		if (c & RBUF_FERR)
537 			cc |= TTY_FE;
538 		if (c & RBUF_PERR)
539 			cc |= TTY_PE;
540 		(*linesw[tp->t_line].l_rint)(cc, tp);
541 	}
542 	DELAY(10);
543 }
544 
545 void
546 dcxint(tp)
547 	register struct tty *tp;
548 {
549 	register struct pdma *dp;
550 	register dcregs *dcaddr;
551 
552 	dp = (struct pdma *)tp->t_addr;
553 	if (dp->p_mem < dp->p_end) {
554 		dcaddr = (dcregs *)dp->p_addr;
555 		dcaddr->dc_tdr = dc_brk[(tp - dc_tty) >> 2] | *dp->p_mem++;
556 		MachEmptyWriteBuffer();
557 		DELAY(10);
558 		return;
559 	}
560 	tp->t_state &= ~TS_BUSY;
561 	if (tp->t_state & TS_FLUSH)
562 		tp->t_state &= ~TS_FLUSH;
563 	else {
564 		ndflush(&tp->t_outq, dp->p_mem-tp->t_outq.c_cf);
565 		dp->p_end = dp->p_mem = tp->t_outq.c_cf;
566 	}
567 	if (tp->t_line)
568 		(*linesw[tp->t_line].l_start)(tp);
569 	else
570 		dcstart(tp);
571 	if (tp->t_outq.c_cc == 0 || !(tp->t_state & TS_BUSY)) {
572 		dcaddr = (dcregs *)dp->p_addr;
573 		dcaddr->dc_tcr &= ~(1 << (minor(tp->t_dev) & 03));
574 		MachEmptyWriteBuffer();
575 		DELAY(10);
576 	}
577 }
578 
579 void
580 dcstart(tp)
581 	register struct tty *tp;
582 {
583 	register struct pdma *dp;
584 	register dcregs *dcaddr;
585 	register int cc;
586 	int s;
587 
588 	dp = (struct pdma *)tp->t_addr;
589 	dcaddr = (dcregs *)dp->p_addr;
590 	s = spltty();
591 	if (tp->t_state & (TS_TIMEOUT|TS_BUSY|TS_TTSTOP))
592 		goto out;
593 	if (tp->t_outq.c_cc <= tp->t_lowat) {
594 		if (tp->t_state & TS_ASLEEP) {
595 			tp->t_state &= ~TS_ASLEEP;
596 			wakeup((caddr_t)&tp->t_outq);
597 		}
598 		selwakeup(&tp->t_wsel);
599 	}
600 	if (tp->t_outq.c_cc == 0)
601 		goto out;
602 	/* handle console specially */
603 	if (tp == &dc_tty[DCKBD_PORT] && cn_tab.cn_screen) {
604 		while (tp->t_outq.c_cc > 0) {
605 			cc = getc(&tp->t_outq) & 0x7f;
606 			cnputc(cc);
607 		}
608 		/*
609 		 * After we flush the output queue we may need to wake
610 		 * up the process that made the output.
611 		 */
612 		if (tp->t_outq.c_cc <= tp->t_lowat) {
613 			if (tp->t_state & TS_ASLEEP) {
614 				tp->t_state &= ~TS_ASLEEP;
615 				wakeup((caddr_t)&tp->t_outq);
616 			}
617 			selwakeup(&tp->t_wsel);
618 		}
619 		goto out;
620 	}
621 	if (tp->t_flags & (RAW|LITOUT))
622 		cc = ndqb(&tp->t_outq, 0);
623 	else {
624 		cc = ndqb(&tp->t_outq, 0200);
625 		if (cc == 0) {
626 			cc = getc(&tp->t_outq);
627 			timeout(ttrstrt, (void *)tp, (cc & 0x7f) + 6);
628 			tp->t_state |= TS_TIMEOUT;
629 			goto out;
630 		}
631 	}
632 	tp->t_state |= TS_BUSY;
633 	dp->p_end = dp->p_mem = tp->t_outq.c_cf;
634 	dp->p_end += cc;
635 	dcaddr->dc_tcr |= 1 << (minor(tp->t_dev) & 03);
636 	MachEmptyWriteBuffer();
637 out:
638 	splx(s);
639 }
640 
641 /*
642  * Stop output on a line.
643  */
644 /*ARGSUSED*/
645 dcstop(tp, flag)
646 	register struct tty *tp;
647 {
648 	register struct pdma *dp;
649 	register int s;
650 
651 	dp = (struct pdma *)tp->t_addr;
652 	s = spltty();
653 	if (tp->t_state & TS_BUSY) {
654 		dp->p_end = dp->p_mem;
655 		if (!(tp->t_state & TS_TTSTOP))
656 			tp->t_state |= TS_FLUSH;
657 	}
658 	splx(s);
659 }
660 
661 dcmctl(dev, bits, how)
662 	dev_t dev;
663 	int bits, how;
664 {
665 	register dcregs *dcaddr;
666 	register int unit, mbits;
667 	int b, s;
668 	register int msr;
669 
670 	unit = minor(dev);
671 	b = 1 << (unit & 03);
672 	dcaddr = (dcregs *)dcpdma[unit].p_addr;
673 	s = spltty();
674 	/* only channel 2 has modem control (what about line 3?) */
675 	mbits = DML_DTR | DML_DSR | DML_CAR;
676 	switch (unit & 03) {
677 	case 2:
678 		mbits = 0;
679 		if (dcaddr->dc_tcr & TCR_DTR2)
680 			mbits |= DML_DTR;
681 		msr = dcaddr->dc_msr;
682 		if (msr & MSR_CD2)
683 			mbits |= DML_CAR;
684 		if (msr & MSR_DSR2) {
685 			if (pmax_boardtype == DS_PMAX)
686 				mbits |= DML_CAR | DML_DSR;
687 			else
688 				mbits |= DML_DSR;
689 		}
690 		break;
691 
692 	case 3:
693 		if (pmax_boardtype != DS_PMAX) {
694 			mbits = 0;
695 			if (dcaddr->dc_tcr & TCR_DTR3)
696 				mbits |= DML_DTR;
697 			msr = dcaddr->dc_msr;
698 			if (msr & MSR_CD3)
699 				mbits |= DML_CAR;
700 			if (msr & MSR_DSR3)
701 				mbits |= DML_DSR;
702 		}
703 	}
704 	switch (how) {
705 	case DMSET:
706 		mbits = bits;
707 		break;
708 
709 	case DMBIS:
710 		mbits |= bits;
711 		break;
712 
713 	case DMBIC:
714 		mbits &= ~bits;
715 		break;
716 
717 	case DMGET:
718 		(void) splx(s);
719 		return (mbits);
720 	}
721 	switch (unit & 03) {
722 	case 2:
723 		if (mbits & DML_DTR)
724 			dcaddr->dc_tcr |= TCR_DTR2;
725 		else
726 			dcaddr->dc_tcr &= ~TCR_DTR2;
727 		break;
728 
729 	case 3:
730 		if (pmax_boardtype != DS_PMAX) {
731 			if (mbits & DML_DTR)
732 				dcaddr->dc_tcr |= TCR_DTR3;
733 			else
734 				dcaddr->dc_tcr &= ~TCR_DTR3;
735 		}
736 	}
737 	if ((mbits & DML_DTR) && (dcsoftCAR[unit >> 2] & b))
738 		dc_tty[unit].t_state |= TS_CARR_ON;
739 	(void) splx(s);
740 	return (mbits);
741 }
742 
743 /*
744  * This is called by timeout() periodically.
745  * Check to see if modem status bits have changed.
746  */
747 void
748 dcscan(arg)
749 	void *arg;
750 {
751 	register dcregs *dcaddr;
752 	register struct tty *tp;
753 	register int i, bit, car;
754 	int s;
755 
756 	s = spltty();
757 	/* only channel 2 has modem control (what about line 3?) */
758 	dcaddr = (dcregs *)dcpdma[i = 2].p_addr;
759 	tp = &dc_tty[i];
760 	bit = TCR_DTR2;
761 	if (dcsoftCAR[i >> 2] & bit)
762 		car = 1;
763 	else
764 		car = dcaddr->dc_msr & MSR_DSR2;
765 	if (car) {
766 		/* carrier present */
767 		if (!(tp->t_state & TS_CARR_ON))
768 			(void)(*linesw[tp->t_line].l_modem)(tp, 1);
769 	} else if ((tp->t_state & TS_CARR_ON) &&
770 	    (*linesw[tp->t_line].l_modem)(tp, 0) == 0)
771 		dcaddr->dc_tcr &= ~bit;
772 	splx(s);
773 	timeout(dcscan, (void *)0, hz);
774 }
775 
776 /*
777  * ----------------------------------------------------------------------------
778  *
779  * dcGetc --
780  *
781  *	Read a character from a serial line.
782  *
783  * Results:
784  *	A character read from the serial port.
785  *
786  * Side effects:
787  *	None.
788  *
789  * ----------------------------------------------------------------------------
790  */
791 int
792 dcGetc(dev)
793 	dev_t dev;
794 {
795 	register dcregs *dcaddr;
796 	register int c;
797 	int s;
798 
799 	dcaddr = (dcregs *)dcpdma[minor(dev)].p_addr;
800 	if (!dcaddr)
801 		return (0);
802 	s = spltty();
803 	for (;;) {
804 		if (!(dcaddr->dc_csr & CSR_RDONE))
805 			continue;
806 		c = dcaddr->dc_rbuf;
807 		DELAY(10);
808 		if (((c >> 8) & 03) == (minor(dev) & 03))
809 			break;
810 	}
811 	splx(s);
812 	return (c & 0xff);
813 }
814 
815 /*
816  * Send a char on a port, non interrupt driven.
817  */
818 void
819 dcPutc(dev, c)
820 	dev_t dev;
821 	int c;
822 {
823 	register dcregs *dcaddr;
824 	register u_short tcr;
825 	register int timeout;
826 	int s, line;
827 
828 	s = spltty();
829 
830 	dcaddr = (dcregs *)dcpdma[minor(dev)].p_addr;
831 	tcr = dcaddr->dc_tcr;
832 	dcaddr->dc_tcr = tcr | (1 << minor(dev));
833 	MachEmptyWriteBuffer();
834 	DELAY(10);
835 	while (1) {
836 		/*
837 		 * Wait for transmitter to be not busy.
838 		 */
839 		timeout = 1000000;
840 		while (!(dcaddr->dc_csr & CSR_TRDY) && timeout > 0)
841 			timeout--;
842 		if (timeout == 0) {
843 			printf("dcPutc: timeout waiting for CSR_TRDY\n");
844 			break;
845 		}
846 		line = (dcaddr->dc_csr >> 8) & 3;
847 		/*
848 		 * Check to be sure its the right port.
849 		 */
850 		if (line != minor(dev)) {
851 			tcr |= 1 << line;
852 			dcaddr->dc_tcr &= ~(1 << line);
853 			MachEmptyWriteBuffer();
854 			DELAY(10);
855 			continue;
856 		}
857 		/*
858 		 * Start sending the character.
859 		 */
860 		dcaddr->dc_tdr = dc_brk[0] | (c & 0xff);
861 		MachEmptyWriteBuffer();
862 		DELAY(10);
863 		/*
864 		 * Wait for character to be sent.
865 		 */
866 		while (1) {
867 			/*
868 			 * cc -O bug: this code produces and infinite loop!
869 			 * while (!(dcaddr->dc_csr & CSR_TRDY))
870 			 *	;
871 			 */
872 			timeout = 1000000;
873 			while (!(dcaddr->dc_csr & CSR_TRDY) && timeout > 0)
874 				timeout--;
875 			line = (dcaddr->dc_csr >> 8) & 3;
876 			if (line != minor(dev)) {
877 				tcr |= 1 << line;
878 				dcaddr->dc_tcr &= ~(1 << line);
879 				MachEmptyWriteBuffer();
880 				DELAY(10);
881 				continue;
882 			}
883 			dcaddr->dc_tcr &= ~(1 << minor(dev));
884 			MachEmptyWriteBuffer();
885 			DELAY(10);
886 			break;
887 		}
888 		break;
889 	}
890 	/*
891 	 * Enable interrupts for other lines which became ready.
892 	 */
893 	if (tcr & 0xF) {
894 		dcaddr->dc_tcr = tcr;
895 		MachEmptyWriteBuffer();
896 		DELAY(10);
897 	}
898 
899 	splx(s);
900 }
901 #endif /* NDC */
902