xref: /netbsd/sys/dev/ic/z8530tty.c (revision c4a72b64)
1 /*	$NetBSD: z8530tty.c,v 1.86 2002/11/09 19:22:54 thorpej Exp $	*/
2 
3 /*-
4  * Copyright (c) 1993, 1994, 1995, 1996, 1997, 1998, 1999
5  *	Charles M. Hannum.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by Charles M. Hannum.
18  * 4. The name of the author may not be used to endorse or promote products
19  *    derived from this software without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
22  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
23  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
24  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
26  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
28  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
29  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
30  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31  */
32 
33 /*
34  * Copyright (c) 1994 Gordon W. Ross
35  * Copyright (c) 1992, 1993
36  *	The Regents of the University of California.  All rights reserved.
37  *
38  * This software was developed by the Computer Systems Engineering group
39  * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
40  * contributed to Berkeley.
41  *
42  * All advertising materials mentioning features or use of this software
43  * must display the following acknowledgement:
44  *	This product includes software developed by the University of
45  *	California, Lawrence Berkeley Laboratory.
46  *
47  * Redistribution and use in source and binary forms, with or without
48  * modification, are permitted provided that the following conditions
49  * are met:
50  * 1. Redistributions of source code must retain the above copyright
51  *    notice, this list of conditions and the following disclaimer.
52  * 2. Redistributions in binary form must reproduce the above copyright
53  *    notice, this list of conditions and the following disclaimer in the
54  *    documentation and/or other materials provided with the distribution.
55  * 3. All advertising materials mentioning features or use of this software
56  *    must display the following acknowledgement:
57  *	This product includes software developed by the University of
58  *	California, Berkeley and its contributors.
59  * 4. Neither the name of the University nor the names of its contributors
60  *    may be used to endorse or promote products derived from this software
61  *    without specific prior written permission.
62  *
63  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
64  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
65  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
66  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
67  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
68  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
69  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
70  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
71  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
72  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
73  * SUCH DAMAGE.
74  *
75  *	@(#)zs.c	8.1 (Berkeley) 7/19/93
76  */
77 
78 /*
79  * Zilog Z8530 Dual UART driver (tty interface)
80  *
81  * This is the "slave" driver that will be attached to
82  * the "zsc" driver for plain "tty" async. serial lines.
83  *
84  * Credits, history:
85  *
86  * The original version of this code was the sparc/dev/zs.c driver
87  * as distributed with the Berkeley 4.4 Lite release.  Since then,
88  * Gordon Ross reorganized the code into the current parent/child
89  * driver scheme, separating the Sun keyboard and mouse support
90  * into independent child drivers.
91  *
92  * RTS/CTS flow-control support was a collaboration of:
93  *	Gordon Ross <gwr@netbsd.org>,
94  *	Bill Studenmund <wrstuden@loki.stanford.edu>
95  *	Ian Dall <Ian.Dall@dsto.defence.gov.au>
96  *
97  * The driver was massively overhauled in November 1997 by Charles Hannum,
98  * fixing *many* bugs, and substantially improving performance.
99  */
100 
101 #include <sys/cdefs.h>
102 __KERNEL_RCSID(0, "$NetBSD: z8530tty.c,v 1.86 2002/11/09 19:22:54 thorpej Exp $");
103 
104 #include "opt_kgdb.h"
105 
106 #include <sys/param.h>
107 #include <sys/systm.h>
108 #include <sys/proc.h>
109 #include <sys/device.h>
110 #include <sys/conf.h>
111 #include <sys/file.h>
112 #include <sys/ioctl.h>
113 #include <sys/malloc.h>
114 #include <sys/timepps.h>
115 #include <sys/tty.h>
116 #include <sys/time.h>
117 #include <sys/kernel.h>
118 #include <sys/syslog.h>
119 
120 #include <dev/ic/z8530reg.h>
121 #include <machine/z8530var.h>
122 
123 #include <dev/cons.h>
124 
125 #include "locators.h"
126 
127 /*
128  * How many input characters we can buffer.
129  * The port-specific var.h may override this.
130  * Note: must be a power of two!
131  */
132 #ifndef	ZSTTY_RING_SIZE
133 #define	ZSTTY_RING_SIZE	2048
134 #endif
135 
136 static struct cnm_state zstty_cnm_state;
137 /*
138  * Make this an option variable one can patch.
139  * But be warned:  this must be a power of 2!
140  */
141 u_int zstty_rbuf_size = ZSTTY_RING_SIZE;
142 
143 /* Stop input when 3/4 of the ring is full; restart when only 1/4 is full. */
144 u_int zstty_rbuf_hiwat = (ZSTTY_RING_SIZE * 1) / 4;
145 u_int zstty_rbuf_lowat = (ZSTTY_RING_SIZE * 3) / 4;
146 
147 static int zsppscap =
148 	PPS_TSFMT_TSPEC |
149 	PPS_CAPTUREASSERT |
150 	PPS_CAPTURECLEAR |
151 #ifdef  PPS_SYNC
152 	PPS_HARDPPSONASSERT | PPS_HARDPPSONCLEAR |
153 #endif	/* PPS_SYNC */
154 	PPS_OFFSETASSERT | PPS_OFFSETCLEAR;
155 
156 struct zstty_softc {
157 	struct	device zst_dev;		/* required first: base device */
158 	struct  tty *zst_tty;
159 	struct	zs_chanstate *zst_cs;
160 
161 	struct callout zst_diag_ch;
162 
163 	u_int zst_overflows,
164 	      zst_floods,
165 	      zst_errors;
166 
167 	int zst_hwflags,	/* see z8530var.h */
168 	    zst_swflags;	/* TIOCFLAG_SOFTCAR, ... <ttycom.h> */
169 
170 	u_int zst_r_hiwat,
171 	      zst_r_lowat;
172 	u_char *volatile zst_rbget,
173 	       *volatile zst_rbput;
174 	volatile u_int zst_rbavail;
175 	u_char *zst_rbuf,
176 	       *zst_ebuf;
177 
178 	/*
179 	 * The transmit byte count and address are used for pseudo-DMA
180 	 * output in the hardware interrupt code.  PDMA can be suspended
181 	 * to get pending changes done; heldtbc is used for this.  It can
182 	 * also be stopped for ^S; this sets TS_TTSTOP in tp->t_state.
183 	 */
184 	u_char *zst_tba;		/* transmit buffer address */
185 	u_int zst_tbc,			/* transmit byte count */
186 	      zst_heldtbc;		/* held tbc while xmission stopped */
187 
188 	/* Flags to communicate with zstty_softint() */
189 	volatile u_char zst_rx_flags,	/* receiver blocked */
190 #define	RX_TTY_BLOCKED		0x01
191 #define	RX_TTY_OVERFLOWED	0x02
192 #define	RX_IBUF_BLOCKED		0x04
193 #define	RX_IBUF_OVERFLOWED	0x08
194 #define	RX_ANY_BLOCK		0x0f
195 			zst_tx_busy,	/* working on an output chunk */
196 			zst_tx_done,	/* done with one output chunk */
197 			zst_tx_stopped,	/* H/W level stop (lost CTS) */
198 			zst_st_check,	/* got a status interrupt */
199 			zst_rx_ready;
200 
201 	/* PPS signal on DCD, with or without inkernel clock disciplining */
202 	u_char  zst_ppsmask;			/* pps signal mask */
203 	u_char  zst_ppsassert;			/* pps leading edge */
204 	u_char  zst_ppsclear;			/* pps trailing edge */
205 	pps_info_t ppsinfo;
206 	pps_params_t ppsparam;
207 };
208 
209 /* Macros to clear/set/test flags. */
210 #define SET(t, f)	(t) |= (f)
211 #define CLR(t, f)	(t) &= ~(f)
212 #define ISSET(t, f)	((t) & (f))
213 
214 /* Definition of the driver for autoconfig. */
215 static int	zstty_match(struct device *, struct cfdata *, void *);
216 static void	zstty_attach(struct device *, struct device *, void *);
217 
218 CFATTACH_DECL(zstty, sizeof(struct zstty_softc),
219     zstty_match, zstty_attach, NULL, NULL);
220 
221 extern struct cfdriver zstty_cd;
222 
223 dev_type_open(zsopen);
224 dev_type_close(zsclose);
225 dev_type_read(zsread);
226 dev_type_write(zswrite);
227 dev_type_ioctl(zsioctl);
228 dev_type_stop(zsstop);
229 dev_type_tty(zstty);
230 dev_type_poll(zspoll);
231 
232 const struct cdevsw zstty_cdevsw = {
233 	zsopen, zsclose, zsread, zswrite, zsioctl,
234 	zsstop, zstty, zspoll, nommap, ttykqfilter, D_TTY
235 };
236 
237 struct zsops zsops_tty;
238 
239 static void zs_shutdown __P((struct zstty_softc *));
240 static void	zsstart __P((struct tty *));
241 static int	zsparam __P((struct tty *, struct termios *));
242 static void zs_modem __P((struct zstty_softc *, int));
243 static void tiocm_to_zs __P((struct zstty_softc *, u_long, int));
244 static int  zs_to_tiocm __P((struct zstty_softc *));
245 static int    zshwiflow __P((struct tty *, int));
246 static void  zs_hwiflow __P((struct zstty_softc *));
247 static void zs_maskintr __P((struct zstty_softc *));
248 
249 /* Low-level routines. */
250 static void zstty_rxint   __P((struct zs_chanstate *));
251 static void zstty_stint   __P((struct zs_chanstate *, int));
252 static void zstty_txint   __P((struct zs_chanstate *));
253 static void zstty_softint __P((struct zs_chanstate *));
254 
255 #define	ZSUNIT(x)	(minor(x) & 0x7ffff)
256 #define	ZSDIALOUT(x)	(minor(x) & 0x80000)
257 
258 /*
259  * zstty_match: how is this zs channel configured?
260  */
261 int
262 zstty_match(parent, cf, aux)
263 	struct device *parent;
264 	struct cfdata *cf;
265 	void   *aux;
266 {
267 	struct zsc_attach_args *args = aux;
268 
269 	/* Exact match is better than wildcard. */
270 	if (cf->cf_loc[ZSCCF_CHANNEL] == args->channel)
271 		return 2;
272 
273 	/* This driver accepts wildcard. */
274 	if (cf->cf_loc[ZSCCF_CHANNEL] == ZSCCF_CHANNEL_DEFAULT)
275 		return 1;
276 
277 	return 0;
278 }
279 
280 void
281 zstty_attach(parent, self, aux)
282 	struct device *parent, *self;
283 	void   *aux;
284 
285 {
286 	struct zsc_softc *zsc = (void *) parent;
287 	struct zstty_softc *zst = (void *) self;
288 	struct cfdata *cf = self->dv_cfdata;
289 	struct zsc_attach_args *args = aux;
290 	struct zs_chanstate *cs;
291 	struct tty *tp;
292 	int channel, s, tty_unit;
293 	dev_t dev;
294 	char *i, *o;
295 
296 	callout_init(&zst->zst_diag_ch);
297 	cn_init_magic(&zstty_cnm_state);
298 
299 	tty_unit = zst->zst_dev.dv_unit;
300 	channel = args->channel;
301 	cs = zsc->zsc_cs[channel];
302 	cs->cs_private = zst;
303 	cs->cs_ops = &zsops_tty;
304 
305 	zst->zst_cs = cs;
306 	zst->zst_swflags = cf->cf_flags;	/* softcar, etc. */
307 	zst->zst_hwflags = args->hwflags;
308 	dev = makedev(cdevsw_lookup_major(&zstty_cdevsw), tty_unit);
309 
310 	if (zst->zst_swflags)
311 		printf(" flags 0x%x", zst->zst_swflags);
312 
313 	/*
314 	 * Check whether we serve as a console device.
315 	 * XXX - split console input/output channels aren't
316 	 *	 supported yet on /dev/console
317 	 */
318 	i = o = NULL;
319 	if ((zst->zst_hwflags & ZS_HWFLAG_CONSOLE_INPUT) != 0) {
320 		i = "input";
321 		if ((args->hwflags & ZS_HWFLAG_USE_CONSDEV) != 0) {
322 			args->consdev->cn_dev = dev;
323 			cn_tab->cn_pollc = args->consdev->cn_pollc;
324 			cn_tab->cn_getc = args->consdev->cn_getc;
325 		}
326 		cn_tab->cn_dev = dev;
327 		/* Set console magic to BREAK */
328 		cn_set_magic("\047\001");
329 	}
330 	if ((zst->zst_hwflags & ZS_HWFLAG_CONSOLE_OUTPUT) != 0) {
331 		o = "output";
332 		if ((args->hwflags & ZS_HWFLAG_USE_CONSDEV) != 0) {
333 			cn_tab->cn_putc = args->consdev->cn_putc;
334 		}
335 		cn_tab->cn_dev = dev;
336 	}
337 	if (i != NULL || o != NULL)
338 		printf(" (console %s)", i ? (o ? "i/o" : i) : o);
339 
340 #ifdef KGDB
341 	if (zs_check_kgdb(cs, dev)) {
342 		/*
343 		 * Allow kgdb to "take over" this port.  Returns true
344 		 * if this serial port is in-use by kgdb.
345 		 */
346 		printf(" (kgdb)\n");
347 		/*
348 		 * This is the kgdb port (exclusive use)
349 		 * so skip the normal attach code.
350 		 */
351 		return;
352 	}
353 #endif
354 	printf("\n");
355 
356 	tp = ttymalloc();
357 	tp->t_dev = dev;
358 	tp->t_oproc = zsstart;
359 	tp->t_param = zsparam;
360 	tp->t_hwiflow = zshwiflow;
361 	tty_attach(tp);
362 
363 	zst->zst_tty = tp;
364 	zst->zst_rbuf = malloc(zstty_rbuf_size << 1, M_DEVBUF, M_WAITOK);
365 	zst->zst_ebuf = zst->zst_rbuf + (zstty_rbuf_size << 1);
366 	/* Disable the high water mark. */
367 	zst->zst_r_hiwat = 0;
368 	zst->zst_r_lowat = 0;
369 	zst->zst_rbget = zst->zst_rbput = zst->zst_rbuf;
370 	zst->zst_rbavail = zstty_rbuf_size;
371 
372 	/* if there are no enable/disable functions, assume the device
373 	   is always enabled */
374 	if (!cs->enable)
375 		cs->enabled = 1;
376 
377 	/*
378 	 * Hardware init
379 	 */
380 	if (ISSET(zst->zst_hwflags, ZS_HWFLAG_CONSOLE)) {
381 		/* Call zsparam similar to open. */
382 		struct termios t;
383 
384 		/* Wait a while for previous console output to complete */
385 		DELAY(10000);
386 
387 		/* Setup the "new" parameters in t. */
388 		t.c_ispeed = 0;
389 		t.c_ospeed = cs->cs_defspeed;
390 		t.c_cflag = cs->cs_defcflag;
391 
392 		s = splzs();
393 
394 		/*
395 		 * Turn on receiver and status interrupts.
396 		 * We defer the actual write of the register to zsparam(),
397 		 * but we must make sure status interrupts are turned on by
398 		 * the time zsparam() reads the initial rr0 state.
399 		 */
400 		SET(cs->cs_preg[1], ZSWR1_RIE | ZSWR1_SIE);
401 
402 		splx(s);
403 
404 		/* Make sure zsparam will see changes. */
405 		tp->t_ospeed = 0;
406 		(void) zsparam(tp, &t);
407 
408 		s = splzs();
409 
410 		/* Make sure DTR is on now. */
411 		zs_modem(zst, 1);
412 
413 		splx(s);
414 	} else if (!ISSET(zst->zst_hwflags, ZS_HWFLAG_NORESET)) {
415 		/* Not the console; may need reset. */
416 		int reset;
417 
418 		reset = (channel == 0) ? ZSWR9_A_RESET : ZSWR9_B_RESET;
419 
420 		s = splzs();
421 
422 		zs_write_reg(cs, 9, reset);
423 
424 		/* Will raise DTR in open. */
425 		zs_modem(zst, 0);
426 
427 		splx(s);
428 	}
429 }
430 
431 
432 /*
433  * Return pointer to our tty.
434  */
435 struct tty *
436 zstty(dev)
437 	dev_t dev;
438 {
439 	struct zstty_softc *zst = device_lookup(&zstty_cd, ZSUNIT(dev));
440 
441 	return (zst->zst_tty);
442 }
443 
444 
445 void
446 zs_shutdown(zst)
447 	struct zstty_softc *zst;
448 {
449 	struct zs_chanstate *cs = zst->zst_cs;
450 	struct tty *tp = zst->zst_tty;
451 	int s;
452 
453 	s = splzs();
454 
455 	/* If we were asserting flow control, then deassert it. */
456 	SET(zst->zst_rx_flags, RX_IBUF_BLOCKED);
457 	zs_hwiflow(zst);
458 
459 	/* Clear any break condition set with TIOCSBRK. */
460 	zs_break(cs, 0);
461 
462 	/* Turn off PPS capture on last close. */
463 	zst->zst_ppsmask = 0;
464 	zst->ppsparam.mode = 0;
465 
466 	/*
467 	 * Hang up if necessary.  Wait a bit, so the other side has time to
468 	 * notice even if we immediately open the port again.
469 	 */
470 	if (ISSET(tp->t_cflag, HUPCL)) {
471 		zs_modem(zst, 0);
472 		(void) tsleep(cs, TTIPRI, ttclos, hz);
473 	}
474 
475 	/* Turn off interrupts if not the console. */
476 	if (!ISSET(zst->zst_hwflags, ZS_HWFLAG_CONSOLE)) {
477 		CLR(cs->cs_preg[1], ZSWR1_RIE | ZSWR1_SIE);
478 		cs->cs_creg[1] = cs->cs_preg[1];
479 		zs_write_reg(cs, 1, cs->cs_creg[1]);
480 	}
481 
482 	/* Call the power management hook. */
483 	if (cs->disable) {
484 #ifdef DIAGNOSTIC
485 		if (!cs->enabled)
486 			panic("zs_shutdown: not enabled?");
487 #endif
488 		(*cs->disable)(zst->zst_cs);
489 	}
490 
491 	splx(s);
492 }
493 
494 /*
495  * Open a zs serial (tty) port.
496  */
497 int
498 zsopen(dev, flags, mode, p)
499 	dev_t dev;
500 	int flags;
501 	int mode;
502 	struct proc *p;
503 {
504 	struct zstty_softc *zst;
505 	struct zs_chanstate *cs;
506 	struct tty *tp;
507 	int s, s2;
508 	int error;
509 
510 	zst = device_lookup(&zstty_cd, ZSUNIT(dev));
511 	if (zst == NULL)
512 		return (ENXIO);
513 
514 	tp = zst->zst_tty;
515 	cs = zst->zst_cs;
516 
517 	/* If KGDB took the line, then tp==NULL */
518 	if (tp == NULL)
519 		return (EBUSY);
520 
521 	if (ISSET(tp->t_state, TS_ISOPEN) &&
522 	    ISSET(tp->t_state, TS_XCLUDE) &&
523 	    p->p_ucred->cr_uid != 0)
524 		return (EBUSY);
525 
526 	s = spltty();
527 
528 	/*
529 	 * Do the following iff this is a first open.
530 	 */
531 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
532 		struct termios t;
533 
534 		tp->t_dev = dev;
535 
536 		/* Call the power management hook. */
537 		if (cs->enable) {
538 			if ((*cs->enable)(cs)) {
539 				splx(s);
540 				printf("%s: device enable failed\n",
541 			       	zst->zst_dev.dv_xname);
542 				return (EIO);
543 			}
544 		}
545 
546 		/*
547 		 * Initialize the termios status to the defaults.  Add in the
548 		 * sticky bits from TIOCSFLAGS.
549 		 */
550 		t.c_ispeed = 0;
551 		t.c_ospeed = cs->cs_defspeed;
552 		t.c_cflag = cs->cs_defcflag;
553 		if (ISSET(zst->zst_swflags, TIOCFLAG_CLOCAL))
554 			SET(t.c_cflag, CLOCAL);
555 		if (ISSET(zst->zst_swflags, TIOCFLAG_CRTSCTS))
556 			SET(t.c_cflag, CRTSCTS);
557 		if (ISSET(zst->zst_swflags, TIOCFLAG_CDTRCTS))
558 			SET(t.c_cflag, CDTRCTS);
559 		if (ISSET(zst->zst_swflags, TIOCFLAG_MDMBUF))
560 			SET(t.c_cflag, MDMBUF);
561 
562 		s2 = splzs();
563 
564 		/*
565 		 * Turn on receiver and status interrupts.
566 		 * We defer the actual write of the register to zsparam(),
567 		 * but we must make sure status interrupts are turned on by
568 		 * the time zsparam() reads the initial rr0 state.
569 		 */
570 		SET(cs->cs_preg[1], ZSWR1_RIE | ZSWR1_SIE);
571 
572 		/* Clear PPS capture state on first open. */
573 		zst->zst_ppsmask = 0;
574 		zst->ppsparam.mode = 0;
575 
576 		splx(s2);
577 
578 		/* Make sure zsparam will see changes. */
579 		tp->t_ospeed = 0;
580 		(void) zsparam(tp, &t);
581 
582 		/*
583 		 * Note: zsparam has done: cflag, ispeed, ospeed
584 		 * so we just need to do: iflag, oflag, lflag, cc
585 		 * For "raw" mode, just leave all zeros.
586 		 */
587 		if (!ISSET(zst->zst_hwflags, ZS_HWFLAG_RAW)) {
588 			tp->t_iflag = TTYDEF_IFLAG;
589 			tp->t_oflag = TTYDEF_OFLAG;
590 			tp->t_lflag = TTYDEF_LFLAG;
591 		} else {
592 			tp->t_iflag = 0;
593 			tp->t_oflag = 0;
594 			tp->t_lflag = 0;
595 		}
596 		ttychars(tp);
597 		ttsetwater(tp);
598 
599 		s2 = splzs();
600 
601 		/*
602 		 * Turn on DTR.  We must always do this, even if carrier is not
603 		 * present, because otherwise we'd have to use TIOCSDTR
604 		 * immediately after setting CLOCAL, which applications do not
605 		 * expect.  We always assert DTR while the device is open
606 		 * unless explicitly requested to deassert it.
607 		 */
608 		zs_modem(zst, 1);
609 
610 		/* Clear the input ring, and unblock. */
611 		zst->zst_rbget = zst->zst_rbput = zst->zst_rbuf;
612 		zst->zst_rbavail = zstty_rbuf_size;
613 		zs_iflush(cs);
614 		CLR(zst->zst_rx_flags, RX_ANY_BLOCK);
615 		zs_hwiflow(zst);
616 
617 		splx(s2);
618 	}
619 
620 	splx(s);
621 
622 	error = ttyopen(tp, ZSDIALOUT(dev), ISSET(flags, O_NONBLOCK));
623 	if (error)
624 		goto bad;
625 
626 	error = (*tp->t_linesw->l_open)(dev, tp);
627 	if (error)
628 		goto bad;
629 
630 	return (0);
631 
632 bad:
633 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
634 		/*
635 		 * We failed to open the device, and nobody else had it opened.
636 		 * Clean up the state as appropriate.
637 		 */
638 		zs_shutdown(zst);
639 	}
640 
641 	return (error);
642 }
643 
644 /*
645  * Close a zs serial port.
646  */
647 int
648 zsclose(dev, flags, mode, p)
649 	dev_t dev;
650 	int flags;
651 	int mode;
652 	struct proc *p;
653 {
654 	struct zstty_softc *zst = device_lookup(&zstty_cd, ZSUNIT(dev));
655 	struct tty *tp = zst->zst_tty;
656 
657 	/* XXX This is for cons.c. */
658 	if (!ISSET(tp->t_state, TS_ISOPEN))
659 		return 0;
660 
661 	(*tp->t_linesw->l_close)(tp, flags);
662 	ttyclose(tp);
663 
664 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
665 		/*
666 		 * Although we got a last close, the device may still be in
667 		 * use; e.g. if this was the dialout node, and there are still
668 		 * processes waiting for carrier on the non-dialout node.
669 		 */
670 		zs_shutdown(zst);
671 	}
672 
673 	return (0);
674 }
675 
676 /*
677  * Read/write zs serial port.
678  */
679 int
680 zsread(dev, uio, flags)
681 	dev_t dev;
682 	struct uio *uio;
683 	int flags;
684 {
685 	struct zstty_softc *zst = device_lookup(&zstty_cd, ZSUNIT(dev));
686 	struct tty *tp = zst->zst_tty;
687 
688 	return ((*tp->t_linesw->l_read)(tp, uio, flags));
689 }
690 
691 int
692 zswrite(dev, uio, flags)
693 	dev_t dev;
694 	struct uio *uio;
695 	int flags;
696 {
697 	struct zstty_softc *zst = device_lookup(&zstty_cd, ZSUNIT(dev));
698 	struct tty *tp = zst->zst_tty;
699 
700 	return ((*tp->t_linesw->l_write)(tp, uio, flags));
701 }
702 
703 int
704 zspoll(dev, events, p)
705 	dev_t dev;
706 	int events;
707 	struct proc *p;
708 {
709 	struct zstty_softc *zst = device_lookup(&zstty_cd, ZSUNIT(dev));
710 	struct tty *tp = zst->zst_tty;
711 
712 	return ((*tp->t_linesw->l_poll)(tp, events, p));
713 }
714 
715 int
716 zsioctl(dev, cmd, data, flag, p)
717 	dev_t dev;
718 	u_long cmd;
719 	caddr_t data;
720 	int flag;
721 	struct proc *p;
722 {
723 	struct zstty_softc *zst = device_lookup(&zstty_cd, ZSUNIT(dev));
724 	struct zs_chanstate *cs = zst->zst_cs;
725 	struct tty *tp = zst->zst_tty;
726 	int error;
727 	int s;
728 
729 	error = (*tp->t_linesw->l_ioctl)(tp, cmd, data, flag, p);
730 	if (error != EPASSTHROUGH)
731 		return (error);
732 
733 	error = ttioctl(tp, cmd, data, flag, p);
734 	if (error != EPASSTHROUGH)
735 		return (error);
736 
737 #ifdef	ZS_MD_IOCTL
738 	error = ZS_MD_IOCTL(cs, cmd, data);
739 	if (error != EPASSTHROUGH)
740 		return (error);
741 #endif	/* ZS_MD_IOCTL */
742 
743 	error = 0;
744 
745 	s = splzs();
746 
747 	switch (cmd) {
748 	case TIOCSBRK:
749 		zs_break(cs, 1);
750 		break;
751 
752 	case TIOCCBRK:
753 		zs_break(cs, 0);
754 		break;
755 
756 	case TIOCGFLAGS:
757 		*(int *)data = zst->zst_swflags;
758 		break;
759 
760 	case TIOCSFLAGS:
761 		error = suser(p->p_ucred, &p->p_acflag);
762 		if (error)
763 			break;
764 		zst->zst_swflags = *(int *)data;
765 		break;
766 
767 	case TIOCSDTR:
768 		zs_modem(zst, 1);
769 		break;
770 
771 	case TIOCCDTR:
772 		zs_modem(zst, 0);
773 		break;
774 
775 	case TIOCMSET:
776 	case TIOCMBIS:
777 	case TIOCMBIC:
778 		tiocm_to_zs(zst, cmd, *(int *)data);
779 		break;
780 
781 	case TIOCMGET:
782 		*(int *)data = zs_to_tiocm(zst);
783 		break;
784 
785 	case PPS_IOC_CREATE:
786 		break;
787 
788 	case PPS_IOC_DESTROY:
789 		break;
790 
791 	case PPS_IOC_GETPARAMS: {
792 		pps_params_t *pp;
793 		pp = (pps_params_t *)data;
794 		*pp = zst->ppsparam;
795 		break;
796 	}
797 
798 	case PPS_IOC_SETPARAMS: {
799 		pps_params_t *pp;
800 		int mode;
801 		if (cs->cs_rr0_pps == 0) {
802 			error = EINVAL;
803 			break;
804 		}
805 		pp = (pps_params_t *)data;
806 		if (pp->mode & ~zsppscap) {
807 			error = EINVAL;
808 			break;
809 		}
810 		zst->ppsparam = *pp;
811 		/*
812 		 * compute masks from user-specified timestamp state.
813 		 */
814 		mode = zst->ppsparam.mode;
815 #ifdef	PPS_SYNC
816 		if (mode & PPS_HARDPPSONASSERT) {
817 			mode |= PPS_CAPTUREASSERT;
818 			/* XXX revoke any previous HARDPPS source */
819 		}
820 		if (mode & PPS_HARDPPSONCLEAR) {
821 			mode |= PPS_CAPTURECLEAR;
822 			/* XXX revoke any previous HARDPPS source */
823 		}
824 #endif	/* PPS_SYNC */
825 		switch (mode & PPS_CAPTUREBOTH) {
826 		case 0:
827 			zst->zst_ppsmask = 0;
828 			break;
829 
830 		case PPS_CAPTUREASSERT:
831 			zst->zst_ppsmask = ZSRR0_DCD;
832 			zst->zst_ppsassert = ZSRR0_DCD;
833 			zst->zst_ppsclear = -1;
834 			break;
835 
836 		case PPS_CAPTURECLEAR:
837 			zst->zst_ppsmask = ZSRR0_DCD;
838 			zst->zst_ppsassert = -1;
839 			zst->zst_ppsclear = 0;
840 			break;
841 
842 		case PPS_CAPTUREBOTH:
843 			zst->zst_ppsmask = ZSRR0_DCD;
844 			zst->zst_ppsassert = ZSRR0_DCD;
845 			zst->zst_ppsclear = 0;
846 			break;
847 
848 		default:
849 			error = EINVAL;
850 			break;
851 		}
852 
853 		/*
854 		 * Now update interrupts.
855 		 */
856 		zs_maskintr(zst);
857 		/*
858 		 * If nothing is being transmitted, set up new current values,
859 		 * else mark them as pending.
860 		 */
861 		if (!cs->cs_heldchange) {
862 			if (zst->zst_tx_busy) {
863 				zst->zst_heldtbc = zst->zst_tbc;
864 				zst->zst_tbc = 0;
865 				cs->cs_heldchange = 1;
866 			} else
867 				zs_loadchannelregs(cs);
868 		}
869 
870 		break;
871 	}
872 
873 	case PPS_IOC_GETCAP:
874 		*(int *)data = zsppscap;
875 		break;
876 
877 	case PPS_IOC_FETCH: {
878 		pps_info_t *pi;
879 		pi = (pps_info_t *)data;
880 		*pi = zst->ppsinfo;
881 		break;
882 	}
883 
884 	case TIOCDCDTIMESTAMP:	/* XXX old, overloaded  API used by xntpd v3 */
885 		if (cs->cs_rr0_pps == 0) {
886 			error = EINVAL;
887 			break;
888 		}
889 		/*
890 		 * Some GPS clocks models use the falling rather than
891 		 * rising edge as the on-the-second signal.
892 		 * The old API has no way to specify PPS polarity.
893 		 */
894 		zst->zst_ppsmask = ZSRR0_DCD;
895 #ifndef	PPS_TRAILING_EDGE
896 		zst->zst_ppsassert = ZSRR0_DCD;
897 		zst->zst_ppsclear = -1;
898 		TIMESPEC_TO_TIMEVAL((struct timeval *)data,
899 			&zst->ppsinfo.assert_timestamp);
900 #else
901 		zst->zst_ppsassert = -1;
902 		zst->zst_ppsclear = 01;
903 		TIMESPEC_TO_TIMEVAL((struct timeval *)data,
904 			&zst->ppsinfo.clear_timestamp);
905 #endif
906 		/*
907 		 * Now update interrupts.
908 		 */
909 		zs_maskintr(zst);
910 		/*
911 		 * If nothing is being transmitted, set up new current values,
912 		 * else mark them as pending.
913 		 */
914 		if (!cs->cs_heldchange) {
915 			if (zst->zst_tx_busy) {
916 				zst->zst_heldtbc = zst->zst_tbc;
917 				zst->zst_tbc = 0;
918 				cs->cs_heldchange = 1;
919 			} else
920 				zs_loadchannelregs(cs);
921 		}
922 
923 		break;
924 
925 	default:
926 		error = EPASSTHROUGH;
927 		break;
928 	}
929 
930 	splx(s);
931 
932 	return (error);
933 }
934 
935 /*
936  * Start or restart transmission.
937  */
938 static void
939 zsstart(tp)
940 	struct tty *tp;
941 {
942 	struct zstty_softc *zst = device_lookup(&zstty_cd, ZSUNIT(tp->t_dev));
943 	struct zs_chanstate *cs = zst->zst_cs;
944 	int s;
945 
946 	s = spltty();
947 	if (ISSET(tp->t_state, TS_BUSY | TS_TIMEOUT | TS_TTSTOP))
948 		goto out;
949 	if (zst->zst_tx_stopped)
950 		goto out;
951 
952 	if (tp->t_outq.c_cc <= tp->t_lowat) {
953 		if (ISSET(tp->t_state, TS_ASLEEP)) {
954 			CLR(tp->t_state, TS_ASLEEP);
955 			wakeup((caddr_t)&tp->t_outq);
956 		}
957 		selwakeup(&tp->t_wsel);
958 		if (tp->t_outq.c_cc == 0)
959 			goto out;
960 	}
961 
962 	/* Grab the first contiguous region of buffer space. */
963 	{
964 		u_char *tba;
965 		int tbc;
966 
967 		tba = tp->t_outq.c_cf;
968 		tbc = ndqb(&tp->t_outq, 0);
969 
970 		(void) splzs();
971 
972 		zst->zst_tba = tba;
973 		zst->zst_tbc = tbc;
974 	}
975 
976 	SET(tp->t_state, TS_BUSY);
977 	zst->zst_tx_busy = 1;
978 
979 	/* Enable transmit completion interrupts if necessary. */
980 	if (!ISSET(cs->cs_preg[1], ZSWR1_TIE)) {
981 		SET(cs->cs_preg[1], ZSWR1_TIE);
982 		cs->cs_creg[1] = cs->cs_preg[1];
983 		zs_write_reg(cs, 1, cs->cs_creg[1]);
984 	}
985 
986 	/* Output the first character of the contiguous buffer. */
987 	{
988 		zs_write_data(cs, *zst->zst_tba);
989 		zst->zst_tbc--;
990 		zst->zst_tba++;
991 	}
992 out:
993 	splx(s);
994 	return;
995 }
996 
997 /*
998  * Stop output, e.g., for ^S or output flush.
999  */
1000 void
1001 zsstop(tp, flag)
1002 	struct tty *tp;
1003 	int flag;
1004 {
1005 	struct zstty_softc *zst = device_lookup(&zstty_cd, ZSUNIT(tp->t_dev));
1006 	int s;
1007 
1008 	s = splzs();
1009 	if (ISSET(tp->t_state, TS_BUSY)) {
1010 		/* Stop transmitting at the next chunk. */
1011 		zst->zst_tbc = 0;
1012 		zst->zst_heldtbc = 0;
1013 		if (!ISSET(tp->t_state, TS_TTSTOP))
1014 			SET(tp->t_state, TS_FLUSH);
1015 	}
1016 	splx(s);
1017 }
1018 
1019 /*
1020  * Set ZS tty parameters from termios.
1021  * XXX - Should just copy the whole termios after
1022  * making sure all the changes could be done.
1023  */
1024 static int
1025 zsparam(tp, t)
1026 	struct tty *tp;
1027 	struct termios *t;
1028 {
1029 	struct zstty_softc *zst = device_lookup(&zstty_cd, ZSUNIT(tp->t_dev));
1030 	struct zs_chanstate *cs = zst->zst_cs;
1031 	int ospeed;
1032 	tcflag_t cflag;
1033 	u_char tmp3, tmp4, tmp5;
1034 	int s, error;
1035 
1036 	ospeed = t->c_ospeed;
1037 	cflag = t->c_cflag;
1038 
1039 	/* Check requested parameters. */
1040 	if (ospeed < 0)
1041 		return (EINVAL);
1042 	if (t->c_ispeed && t->c_ispeed != ospeed)
1043 		return (EINVAL);
1044 
1045 	/*
1046 	 * For the console, always force CLOCAL and !HUPCL, so that the port
1047 	 * is always active.
1048 	 */
1049 	if (ISSET(zst->zst_swflags, TIOCFLAG_SOFTCAR) ||
1050 	    ISSET(zst->zst_hwflags, ZS_HWFLAG_CONSOLE)) {
1051 		SET(cflag, CLOCAL);
1052 		CLR(cflag, HUPCL);
1053 	}
1054 
1055 	/*
1056 	 * Only whack the UART when params change.
1057 	 * Some callers need to clear tp->t_ospeed
1058 	 * to make sure initialization gets done.
1059 	 */
1060 	if (tp->t_ospeed == ospeed &&
1061 	    tp->t_cflag == cflag)
1062 		return (0);
1063 
1064 	/*
1065 	 * Call MD functions to deal with changed
1066 	 * clock modes or H/W flow control modes.
1067 	 * The BRG divisor is set now. (reg 12,13)
1068 	 */
1069 	error = zs_set_speed(cs, ospeed);
1070 	if (error)
1071 		return (error);
1072 	error = zs_set_modes(cs, cflag);
1073 	if (error)
1074 		return (error);
1075 
1076 	/*
1077 	 * Block interrupts so that state will not
1078 	 * be altered until we are done setting it up.
1079 	 *
1080 	 * Initial values in cs_preg are set before
1081 	 * our attach routine is called.  The master
1082 	 * interrupt enable is handled by zsc.c
1083 	 *
1084 	 */
1085 	s = splzs();
1086 
1087 	/*
1088 	 * Recalculate which status ints to enable.
1089 	 */
1090 	zs_maskintr(zst);
1091 
1092 	/* Recompute character size bits. */
1093 	tmp3 = cs->cs_preg[3];
1094 	tmp5 = cs->cs_preg[5];
1095 	CLR(tmp3, ZSWR3_RXSIZE);
1096 	CLR(tmp5, ZSWR5_TXSIZE);
1097 	switch (ISSET(cflag, CSIZE)) {
1098 	case CS5:
1099 		SET(tmp3, ZSWR3_RX_5);
1100 		SET(tmp5, ZSWR5_TX_5);
1101 		break;
1102 	case CS6:
1103 		SET(tmp3, ZSWR3_RX_6);
1104 		SET(tmp5, ZSWR5_TX_6);
1105 		break;
1106 	case CS7:
1107 		SET(tmp3, ZSWR3_RX_7);
1108 		SET(tmp5, ZSWR5_TX_7);
1109 		break;
1110 	case CS8:
1111 		SET(tmp3, ZSWR3_RX_8);
1112 		SET(tmp5, ZSWR5_TX_8);
1113 		break;
1114 	}
1115 	cs->cs_preg[3] = tmp3;
1116 	cs->cs_preg[5] = tmp5;
1117 
1118 	/*
1119 	 * Recompute the stop bits and parity bits.  Note that
1120 	 * zs_set_speed() may have set clock selection bits etc.
1121 	 * in wr4, so those must preserved.
1122 	 */
1123 	tmp4 = cs->cs_preg[4];
1124 	CLR(tmp4, ZSWR4_SBMASK | ZSWR4_PARMASK);
1125 	if (ISSET(cflag, CSTOPB))
1126 		SET(tmp4, ZSWR4_TWOSB);
1127 	else
1128 		SET(tmp4, ZSWR4_ONESB);
1129 	if (!ISSET(cflag, PARODD))
1130 		SET(tmp4, ZSWR4_EVENP);
1131 	if (ISSET(cflag, PARENB))
1132 		SET(tmp4, ZSWR4_PARENB);
1133 	cs->cs_preg[4] = tmp4;
1134 
1135 	/* And copy to tty. */
1136 	tp->t_ispeed = 0;
1137 	tp->t_ospeed = ospeed;
1138 	tp->t_cflag = cflag;
1139 
1140 	/*
1141 	 * If nothing is being transmitted, set up new current values,
1142 	 * else mark them as pending.
1143 	 */
1144 	if (!cs->cs_heldchange) {
1145 		if (zst->zst_tx_busy) {
1146 			zst->zst_heldtbc = zst->zst_tbc;
1147 			zst->zst_tbc = 0;
1148 			cs->cs_heldchange = 1;
1149 		} else
1150 			zs_loadchannelregs(cs);
1151 	}
1152 
1153 	/*
1154 	 * If hardware flow control is disabled, turn off the buffer water
1155 	 * marks and unblock any soft flow control state.  Otherwise, enable
1156 	 * the water marks.
1157 	 */
1158 	if (!ISSET(cflag, CHWFLOW)) {
1159 		zst->zst_r_hiwat = 0;
1160 		zst->zst_r_lowat = 0;
1161 		if (ISSET(zst->zst_rx_flags, RX_TTY_OVERFLOWED)) {
1162 			CLR(zst->zst_rx_flags, RX_TTY_OVERFLOWED);
1163 			zst->zst_rx_ready = 1;
1164 			cs->cs_softreq = 1;
1165 		}
1166 		if (ISSET(zst->zst_rx_flags, RX_TTY_BLOCKED|RX_IBUF_BLOCKED)) {
1167 			CLR(zst->zst_rx_flags, RX_TTY_BLOCKED|RX_IBUF_BLOCKED);
1168 			zs_hwiflow(zst);
1169 		}
1170 	} else {
1171 		zst->zst_r_hiwat = zstty_rbuf_hiwat;
1172 		zst->zst_r_lowat = zstty_rbuf_lowat;
1173 	}
1174 
1175 	/*
1176 	 * Force a recheck of the hardware carrier and flow control status,
1177 	 * since we may have changed which bits we're looking at.
1178 	 */
1179 	zstty_stint(cs, 1);
1180 
1181 	splx(s);
1182 
1183 	/*
1184 	 * If hardware flow control is disabled, unblock any hard flow control
1185 	 * state.
1186 	 */
1187 	if (!ISSET(cflag, CHWFLOW)) {
1188 		if (zst->zst_tx_stopped) {
1189 			zst->zst_tx_stopped = 0;
1190 			zsstart(tp);
1191 		}
1192 	}
1193 
1194 	zstty_softint(cs);
1195 
1196 	return (0);
1197 }
1198 
1199 /*
1200  * Compute interupt enable bits and set in the pending bits. Called both
1201  * in zsparam() and when PPS (pulse per second timing) state changes.
1202  * Must be called at splzs().
1203  */
1204 static void
1205 zs_maskintr(zst)
1206 	struct zstty_softc *zst;
1207 {
1208 	struct zs_chanstate *cs = zst->zst_cs;
1209 	int tmp15;
1210 
1211 	cs->cs_rr0_mask = cs->cs_rr0_cts | cs->cs_rr0_dcd;
1212 	if (zst->zst_ppsmask != 0)
1213 		cs->cs_rr0_mask |= cs->cs_rr0_pps;
1214 	tmp15 = cs->cs_preg[15];
1215 	if (ISSET(cs->cs_rr0_mask, ZSRR0_DCD))
1216 		SET(tmp15, ZSWR15_DCD_IE);
1217 	else
1218 		CLR(tmp15, ZSWR15_DCD_IE);
1219 	if (ISSET(cs->cs_rr0_mask, ZSRR0_CTS))
1220 		SET(tmp15, ZSWR15_CTS_IE);
1221 	else
1222 		CLR(tmp15, ZSWR15_CTS_IE);
1223 	cs->cs_preg[15] = tmp15;
1224 }
1225 
1226 
1227 /*
1228  * Raise or lower modem control (DTR/RTS) signals.  If a character is
1229  * in transmission, the change is deferred.
1230  */
1231 static void
1232 zs_modem(zst, onoff)
1233 	struct zstty_softc *zst;
1234 	int onoff;
1235 {
1236 	struct zs_chanstate *cs = zst->zst_cs, *ccs;
1237 
1238 	if (cs->cs_wr5_dtr == 0)
1239 		return;
1240 
1241 	ccs = (cs->cs_ctl_chan != NULL ? cs->cs_ctl_chan : cs);
1242 
1243 	if (onoff)
1244 		SET(ccs->cs_preg[5], cs->cs_wr5_dtr);
1245 	else
1246 		CLR(ccs->cs_preg[5], cs->cs_wr5_dtr);
1247 
1248 	if (!cs->cs_heldchange) {
1249 		if (zst->zst_tx_busy) {
1250 			zst->zst_heldtbc = zst->zst_tbc;
1251 			zst->zst_tbc = 0;
1252 			cs->cs_heldchange = 1;
1253 		} else
1254 			zs_loadchannelregs(cs);
1255 	}
1256 }
1257 
1258 static void
1259 tiocm_to_zs(zst, how, ttybits)
1260 	struct zstty_softc *zst;
1261 	u_long how;
1262 	int ttybits;
1263 {
1264 	struct zs_chanstate *cs = zst->zst_cs, *ccs;
1265 	u_char zsbits;
1266 
1267 	ccs = (cs->cs_ctl_chan != NULL ? cs->cs_ctl_chan : cs);
1268 
1269 	zsbits = 0;
1270 	if (ISSET(ttybits, TIOCM_DTR))
1271 		SET(zsbits, ZSWR5_DTR);
1272 	if (ISSET(ttybits, TIOCM_RTS))
1273 		SET(zsbits, ZSWR5_RTS);
1274 
1275 	switch (how) {
1276 	case TIOCMBIC:
1277 		CLR(ccs->cs_preg[5], zsbits);
1278 		break;
1279 
1280 	case TIOCMBIS:
1281 		SET(ccs->cs_preg[5], zsbits);
1282 		break;
1283 
1284 	case TIOCMSET:
1285 		CLR(ccs->cs_preg[5], ZSWR5_RTS | ZSWR5_DTR);
1286 		SET(ccs->cs_preg[5], zsbits);
1287 		break;
1288 	}
1289 
1290 	if (!cs->cs_heldchange) {
1291 		if (zst->zst_tx_busy) {
1292 			zst->zst_heldtbc = zst->zst_tbc;
1293 			zst->zst_tbc = 0;
1294 			cs->cs_heldchange = 1;
1295 		} else
1296 			zs_loadchannelregs(cs);
1297 	}
1298 }
1299 
1300 static int
1301 zs_to_tiocm(zst)
1302 	struct zstty_softc *zst;
1303 {
1304 	struct zs_chanstate *cs = zst->zst_cs, *ccs;
1305 	u_char zsbits;
1306 	int ttybits = 0;
1307 
1308 	ccs = (cs->cs_ctl_chan != NULL ? cs->cs_ctl_chan : cs);
1309 
1310 	zsbits = ccs->cs_preg[5];
1311 	if (ISSET(zsbits, ZSWR5_DTR))
1312 		SET(ttybits, TIOCM_DTR);
1313 	if (ISSET(zsbits, ZSWR5_RTS))
1314 		SET(ttybits, TIOCM_RTS);
1315 
1316 	zsbits = cs->cs_rr0;
1317 	if (ISSET(zsbits, ZSRR0_DCD))
1318 		SET(ttybits, TIOCM_CD);
1319 	if (ISSET(zsbits, ZSRR0_CTS))
1320 		SET(ttybits, TIOCM_CTS);
1321 
1322 	return (ttybits);
1323 }
1324 
1325 /*
1326  * Try to block or unblock input using hardware flow-control.
1327  * This is called by kern/tty.c if MDMBUF|CRTSCTS is set, and
1328  * if this function returns non-zero, the TS_TBLOCK flag will
1329  * be set or cleared according to the "block" arg passed.
1330  */
1331 int
1332 zshwiflow(tp, block)
1333 	struct tty *tp;
1334 	int block;
1335 {
1336 	struct zstty_softc *zst = device_lookup(&zstty_cd, ZSUNIT(tp->t_dev));
1337 	struct zs_chanstate *cs = zst->zst_cs;
1338 	int s;
1339 
1340 	if (cs->cs_wr5_rts == 0)
1341 		return (0);
1342 
1343 	s = splzs();
1344 	if (block) {
1345 		if (!ISSET(zst->zst_rx_flags, RX_TTY_BLOCKED)) {
1346 			SET(zst->zst_rx_flags, RX_TTY_BLOCKED);
1347 			zs_hwiflow(zst);
1348 		}
1349 	} else {
1350 		if (ISSET(zst->zst_rx_flags, RX_TTY_OVERFLOWED)) {
1351 			CLR(zst->zst_rx_flags, RX_TTY_OVERFLOWED);
1352 			zst->zst_rx_ready = 1;
1353 			cs->cs_softreq = 1;
1354 		}
1355 		if (ISSET(zst->zst_rx_flags, RX_TTY_BLOCKED)) {
1356 			CLR(zst->zst_rx_flags, RX_TTY_BLOCKED);
1357 			zs_hwiflow(zst);
1358 		}
1359 	}
1360 	splx(s);
1361 	return (1);
1362 }
1363 
1364 /*
1365  * Internal version of zshwiflow
1366  * called at splzs
1367  */
1368 static void
1369 zs_hwiflow(zst)
1370 	struct zstty_softc *zst;
1371 {
1372 	struct zs_chanstate *cs = zst->zst_cs, *ccs;
1373 
1374 	if (cs->cs_wr5_rts == 0)
1375 		return;
1376 
1377 	ccs = (cs->cs_ctl_chan != NULL ? cs->cs_ctl_chan : cs);
1378 
1379 	if (ISSET(zst->zst_rx_flags, RX_ANY_BLOCK)) {
1380 		CLR(ccs->cs_preg[5], cs->cs_wr5_rts);
1381 		CLR(ccs->cs_creg[5], cs->cs_wr5_rts);
1382 	} else {
1383 		SET(ccs->cs_preg[5], cs->cs_wr5_rts);
1384 		SET(ccs->cs_creg[5], cs->cs_wr5_rts);
1385 	}
1386 	zs_write_reg(ccs, 5, ccs->cs_creg[5]);
1387 }
1388 
1389 
1390 /****************************************************************
1391  * Interface to the lower layer (zscc)
1392  ****************************************************************/
1393 
1394 #define	integrate	static inline
1395 integrate void zstty_rxsoft __P((struct zstty_softc *, struct tty *));
1396 integrate void zstty_txsoft __P((struct zstty_softc *, struct tty *));
1397 integrate void zstty_stsoft __P((struct zstty_softc *, struct tty *));
1398 static void zstty_diag __P((void *));
1399 
1400 /*
1401  * receiver ready interrupt.
1402  * called at splzs
1403  */
1404 static void
1405 zstty_rxint(cs)
1406 	struct zs_chanstate *cs;
1407 {
1408 	struct zstty_softc *zst = cs->cs_private;
1409 	u_char *put, *end;
1410 	u_int cc;
1411 	u_char rr0, rr1, c;
1412 
1413 	end = zst->zst_ebuf;
1414 	put = zst->zst_rbput;
1415 	cc = zst->zst_rbavail;
1416 
1417 	while (cc > 0) {
1418 		/*
1419 		 * First read the status, because reading the received char
1420 		 * destroys the status of this char.
1421 		 */
1422 		rr1 = zs_read_reg(cs, 1);
1423 		c = zs_read_data(cs);
1424 
1425 		if (ISSET(rr1, ZSRR1_FE | ZSRR1_DO | ZSRR1_PE)) {
1426 			/* Clear the receive error. */
1427 			zs_write_csr(cs, ZSWR0_RESET_ERRORS);
1428 		}
1429 
1430 		cn_check_magic(zst->zst_tty->t_dev, c, zstty_cnm_state);
1431 		put[0] = c;
1432 		put[1] = rr1;
1433 		put += 2;
1434 		if (put >= end)
1435 			put = zst->zst_rbuf;
1436 		cc--;
1437 
1438 		rr0 = zs_read_csr(cs);
1439 		if (!ISSET(rr0, ZSRR0_RX_READY))
1440 			break;
1441 	}
1442 
1443 	/*
1444 	 * Current string of incoming characters ended because
1445 	 * no more data was available or we ran out of space.
1446 	 * Schedule a receive event if any data was received.
1447 	 * If we're out of space, turn off receive interrupts.
1448 	 */
1449 	zst->zst_rbput = put;
1450 	zst->zst_rbavail = cc;
1451 	if (!ISSET(zst->zst_rx_flags, RX_TTY_OVERFLOWED)) {
1452 		zst->zst_rx_ready = 1;
1453 		cs->cs_softreq = 1;
1454 	}
1455 
1456 	/*
1457 	 * See if we are in danger of overflowing a buffer. If
1458 	 * so, use hardware flow control to ease the pressure.
1459 	 */
1460 	if (!ISSET(zst->zst_rx_flags, RX_IBUF_BLOCKED) &&
1461 	    cc < zst->zst_r_hiwat) {
1462 		SET(zst->zst_rx_flags, RX_IBUF_BLOCKED);
1463 		zs_hwiflow(zst);
1464 	}
1465 
1466 	/*
1467 	 * If we're out of space, disable receive interrupts
1468 	 * until the queue has drained a bit.
1469 	 */
1470 	if (!cc) {
1471 		SET(zst->zst_rx_flags, RX_IBUF_OVERFLOWED);
1472 		CLR(cs->cs_preg[1], ZSWR1_RIE);
1473 		cs->cs_creg[1] = cs->cs_preg[1];
1474 		zs_write_reg(cs, 1, cs->cs_creg[1]);
1475 	}
1476 
1477 #if 0
1478 	printf("%xH%04d\n", zst->zst_rx_flags, zst->zst_rbavail);
1479 #endif
1480 }
1481 
1482 /*
1483  * transmitter ready interrupt.  (splzs)
1484  */
1485 static void
1486 zstty_txint(cs)
1487 	struct zs_chanstate *cs;
1488 {
1489 	struct zstty_softc *zst = cs->cs_private;
1490 
1491 	/*
1492 	 * If we've delayed a parameter change, do it now, and restart
1493 	 * output.
1494 	 */
1495 	if (cs->cs_heldchange) {
1496 		zs_loadchannelregs(cs);
1497 		cs->cs_heldchange = 0;
1498 		zst->zst_tbc = zst->zst_heldtbc;
1499 		zst->zst_heldtbc = 0;
1500 	}
1501 
1502 	/* Output the next character in the buffer, if any. */
1503 	if (zst->zst_tbc > 0) {
1504 		zs_write_data(cs, *zst->zst_tba);
1505 		zst->zst_tbc--;
1506 		zst->zst_tba++;
1507 	} else {
1508 		/* Disable transmit completion interrupts if necessary. */
1509 		if (ISSET(cs->cs_preg[1], ZSWR1_TIE)) {
1510 			CLR(cs->cs_preg[1], ZSWR1_TIE);
1511 			cs->cs_creg[1] = cs->cs_preg[1];
1512 			zs_write_reg(cs, 1, cs->cs_creg[1]);
1513 		}
1514 		if (zst->zst_tx_busy) {
1515 			zst->zst_tx_busy = 0;
1516 			zst->zst_tx_done = 1;
1517 			cs->cs_softreq = 1;
1518 		}
1519 	}
1520 }
1521 
1522 /*
1523  * status change interrupt.  (splzs)
1524  */
1525 static void
1526 zstty_stint(cs, force)
1527 	struct zs_chanstate *cs;
1528 	int force;
1529 {
1530 	struct zstty_softc *zst = cs->cs_private;
1531 	u_char rr0, delta;
1532 
1533 	rr0 = zs_read_csr(cs);
1534 	zs_write_csr(cs, ZSWR0_RESET_STATUS);
1535 
1536 	/*
1537 	 * Check here for console break, so that we can abort
1538 	 * even when interrupts are locking up the machine.
1539 	 */
1540 	if (ISSET(rr0, ZSRR0_BREAK))
1541 		cn_check_magic(zst->zst_tty->t_dev, CNC_BREAK, zstty_cnm_state);
1542 
1543 	if (!force)
1544 		delta = rr0 ^ cs->cs_rr0;
1545 	else
1546 		delta = cs->cs_rr0_mask;
1547 	cs->cs_rr0 = rr0;
1548 
1549 	if (ISSET(delta, cs->cs_rr0_mask)) {
1550 		SET(cs->cs_rr0_delta, delta);
1551 
1552 		/*
1553 		 * Pulse-per-second clock signal on edge of DCD?
1554 		 */
1555 		if (ISSET(delta, zst->zst_ppsmask)) {
1556 			struct timeval tv;
1557 			if (ISSET(rr0, zst->zst_ppsmask) == zst->zst_ppsassert) {
1558 				/* XXX nanotime() */
1559 				microtime(&tv);
1560 				TIMEVAL_TO_TIMESPEC(&tv,
1561 					&zst->ppsinfo.assert_timestamp);
1562 				if (zst->ppsparam.mode & PPS_OFFSETASSERT) {
1563 					timespecadd(&zst->ppsinfo.assert_timestamp,
1564 					    &zst->ppsparam.assert_offset,
1565 					    &zst->ppsinfo.assert_timestamp);
1566 				}
1567 
1568 #ifdef PPS_SYNC
1569 				if (zst->ppsparam.mode & PPS_HARDPPSONASSERT)
1570 					hardpps(&tv, tv.tv_usec);
1571 #endif
1572 				zst->ppsinfo.assert_sequence++;
1573 				zst->ppsinfo.current_mode = zst->ppsparam.mode;
1574 			} else if (ISSET(rr0, zst->zst_ppsmask) ==
1575 						zst->zst_ppsclear) {
1576 				/* XXX nanotime() */
1577 				microtime(&tv);
1578 				TIMEVAL_TO_TIMESPEC(&tv,
1579 					&zst->ppsinfo.clear_timestamp);
1580 				if (zst->ppsparam.mode & PPS_OFFSETCLEAR) {
1581 					timespecadd(&zst->ppsinfo.clear_timestamp,
1582 						&zst->ppsparam.clear_offset,
1583 						&zst->ppsinfo.clear_timestamp);
1584 				}
1585 
1586 #ifdef PPS_SYNC
1587 				if (zst->ppsparam.mode & PPS_HARDPPSONCLEAR)
1588 					hardpps(&tv, tv.tv_usec);
1589 #endif
1590 				zst->ppsinfo.clear_sequence++;
1591 				zst->ppsinfo.current_mode = zst->ppsparam.mode;
1592 			}
1593 		}
1594 
1595 		/*
1596 		 * Stop output immediately if we lose the output
1597 		 * flow control signal or carrier detect.
1598 		 */
1599 		if (ISSET(~rr0, cs->cs_rr0_mask)) {
1600 			zst->zst_tbc = 0;
1601 			zst->zst_heldtbc = 0;
1602 		}
1603 
1604 		zst->zst_st_check = 1;
1605 		cs->cs_softreq = 1;
1606 	}
1607 }
1608 
1609 void
1610 zstty_diag(arg)
1611 	void *arg;
1612 {
1613 	struct zstty_softc *zst = arg;
1614 	int overflows, floods;
1615 	int s;
1616 
1617 	s = splzs();
1618 	overflows = zst->zst_overflows;
1619 	zst->zst_overflows = 0;
1620 	floods = zst->zst_floods;
1621 	zst->zst_floods = 0;
1622 	zst->zst_errors = 0;
1623 	splx(s);
1624 
1625 	log(LOG_WARNING, "%s: %d silo overflow%s, %d ibuf flood%s\n",
1626 	    zst->zst_dev.dv_xname,
1627 	    overflows, overflows == 1 ? "" : "s",
1628 	    floods, floods == 1 ? "" : "s");
1629 }
1630 
1631 integrate void
1632 zstty_rxsoft(zst, tp)
1633 	struct zstty_softc *zst;
1634 	struct tty *tp;
1635 {
1636 	struct zs_chanstate *cs = zst->zst_cs;
1637 	int (*rint) __P((int c, struct tty *tp)) = tp->t_linesw->l_rint;
1638 	u_char *get, *end;
1639 	u_int cc, scc;
1640 	u_char rr1;
1641 	int code;
1642 	int s;
1643 
1644 	end = zst->zst_ebuf;
1645 	get = zst->zst_rbget;
1646 	scc = cc = zstty_rbuf_size - zst->zst_rbavail;
1647 
1648 	if (cc == zstty_rbuf_size) {
1649 		zst->zst_floods++;
1650 		if (zst->zst_errors++ == 0)
1651 			callout_reset(&zst->zst_diag_ch, 60 * hz,
1652 			    zstty_diag, zst);
1653 	}
1654 
1655 	/* If not yet open, drop the entire buffer content here */
1656 	if (!ISSET(tp->t_state, TS_ISOPEN)) {
1657 		get += cc << 1;
1658 		if (get >= end)
1659 			get -= zstty_rbuf_size << 1;
1660 		cc = 0;
1661 	}
1662 	while (cc) {
1663 		code = get[0];
1664 		rr1 = get[1];
1665 		if (ISSET(rr1, ZSRR1_DO | ZSRR1_FE | ZSRR1_PE)) {
1666 			if (ISSET(rr1, ZSRR1_DO)) {
1667 				zst->zst_overflows++;
1668 				if (zst->zst_errors++ == 0)
1669 					callout_reset(&zst->zst_diag_ch,
1670 					    60 * hz, zstty_diag, zst);
1671 			}
1672 			if (ISSET(rr1, ZSRR1_FE))
1673 				SET(code, TTY_FE);
1674 			if (ISSET(rr1, ZSRR1_PE))
1675 				SET(code, TTY_PE);
1676 		}
1677 		if ((*rint)(code, tp) == -1) {
1678 			/*
1679 			 * The line discipline's buffer is out of space.
1680 			 */
1681 			if (!ISSET(zst->zst_rx_flags, RX_TTY_BLOCKED)) {
1682 				/*
1683 				 * We're either not using flow control, or the
1684 				 * line discipline didn't tell us to block for
1685 				 * some reason.  Either way, we have no way to
1686 				 * know when there's more space available, so
1687 				 * just drop the rest of the data.
1688 				 */
1689 				get += cc << 1;
1690 				if (get >= end)
1691 					get -= zstty_rbuf_size << 1;
1692 				cc = 0;
1693 			} else {
1694 				/*
1695 				 * Don't schedule any more receive processing
1696 				 * until the line discipline tells us there's
1697 				 * space available (through comhwiflow()).
1698 				 * Leave the rest of the data in the input
1699 				 * buffer.
1700 				 */
1701 				SET(zst->zst_rx_flags, RX_TTY_OVERFLOWED);
1702 			}
1703 			break;
1704 		}
1705 		get += 2;
1706 		if (get >= end)
1707 			get = zst->zst_rbuf;
1708 		cc--;
1709 	}
1710 
1711 	if (cc != scc) {
1712 		zst->zst_rbget = get;
1713 		s = splzs();
1714 		cc = zst->zst_rbavail += scc - cc;
1715 		/* Buffers should be ok again, release possible block. */
1716 		if (cc >= zst->zst_r_lowat) {
1717 			if (ISSET(zst->zst_rx_flags, RX_IBUF_OVERFLOWED)) {
1718 				CLR(zst->zst_rx_flags, RX_IBUF_OVERFLOWED);
1719 				SET(cs->cs_preg[1], ZSWR1_RIE);
1720 				cs->cs_creg[1] = cs->cs_preg[1];
1721 				zs_write_reg(cs, 1, cs->cs_creg[1]);
1722 			}
1723 			if (ISSET(zst->zst_rx_flags, RX_IBUF_BLOCKED)) {
1724 				CLR(zst->zst_rx_flags, RX_IBUF_BLOCKED);
1725 				zs_hwiflow(zst);
1726 			}
1727 		}
1728 		splx(s);
1729 	}
1730 
1731 #if 0
1732 	printf("%xS%04d\n", zst->zst_rx_flags, zst->zst_rbavail);
1733 #endif
1734 }
1735 
1736 integrate void
1737 zstty_txsoft(zst, tp)
1738 	struct zstty_softc *zst;
1739 	struct tty *tp;
1740 {
1741 
1742 	CLR(tp->t_state, TS_BUSY);
1743 	if (ISSET(tp->t_state, TS_FLUSH))
1744 		CLR(tp->t_state, TS_FLUSH);
1745 	else
1746 		ndflush(&tp->t_outq, (int)(zst->zst_tba - tp->t_outq.c_cf));
1747 	(*tp->t_linesw->l_start)(tp);
1748 }
1749 
1750 integrate void
1751 zstty_stsoft(zst, tp)
1752 	struct zstty_softc *zst;
1753 	struct tty *tp;
1754 {
1755 	struct zs_chanstate *cs = zst->zst_cs;
1756 	u_char rr0, delta;
1757 	int s;
1758 
1759 	s = splzs();
1760 	rr0 = cs->cs_rr0;
1761 	delta = cs->cs_rr0_delta;
1762 	cs->cs_rr0_delta = 0;
1763 	splx(s);
1764 
1765 	if (ISSET(delta, cs->cs_rr0_dcd)) {
1766 		/*
1767 		 * Inform the tty layer that carrier detect changed.
1768 		 */
1769 		(void) (*tp->t_linesw->l_modem)(tp, ISSET(rr0, ZSRR0_DCD));
1770 	}
1771 
1772 	if (ISSET(delta, cs->cs_rr0_cts)) {
1773 		/* Block or unblock output according to flow control. */
1774 		if (ISSET(rr0, cs->cs_rr0_cts)) {
1775 			zst->zst_tx_stopped = 0;
1776 			(*tp->t_linesw->l_start)(tp);
1777 		} else {
1778 			zst->zst_tx_stopped = 1;
1779 		}
1780 	}
1781 }
1782 
1783 /*
1784  * Software interrupt.  Called at zssoft
1785  *
1786  * The main job to be done here is to empty the input ring
1787  * by passing its contents up to the tty layer.  The ring is
1788  * always emptied during this operation, therefore the ring
1789  * must not be larger than the space after "high water" in
1790  * the tty layer, or the tty layer might drop our input.
1791  *
1792  * Note: an "input blockage" condition is assumed to exist if
1793  * EITHER the TS_TBLOCK flag or zst_rx_blocked flag is set.
1794  */
1795 static void
1796 zstty_softint(cs)
1797 	struct zs_chanstate *cs;
1798 {
1799 	struct zstty_softc *zst = cs->cs_private;
1800 	struct tty *tp = zst->zst_tty;
1801 	int s;
1802 
1803 	s = spltty();
1804 
1805 	if (zst->zst_rx_ready) {
1806 		zst->zst_rx_ready = 0;
1807 		zstty_rxsoft(zst, tp);
1808 	}
1809 
1810 	if (zst->zst_st_check) {
1811 		zst->zst_st_check = 0;
1812 		zstty_stsoft(zst, tp);
1813 	}
1814 
1815 	if (zst->zst_tx_done) {
1816 		zst->zst_tx_done = 0;
1817 		zstty_txsoft(zst, tp);
1818 	}
1819 
1820 	splx(s);
1821 }
1822 
1823 struct zsops zsops_tty = {
1824 	zstty_rxint,	/* receive char available */
1825 	zstty_stint,	/* external/status */
1826 	zstty_txint,	/* xmit buffer empty */
1827 	zstty_softint,	/* process software interrupt */
1828 };
1829