z8530tty.c revision 1.64
1/*	$NetBSD: z8530tty.c,v 1.64 2000/03/19 12:42:45 pk 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/param.h>
102#include <sys/systm.h>
103#include <sys/proc.h>
104#include <sys/device.h>
105#include <sys/conf.h>
106#include <sys/file.h>
107#include <sys/ioctl.h>
108#include <sys/malloc.h>
109#include <sys/timepps.h>
110#include <sys/tty.h>
111#include <sys/time.h>
112#include <sys/kernel.h>
113#include <sys/syslog.h>
114
115#include <dev/ic/z8530reg.h>
116#include <machine/z8530var.h>
117
118#include <dev/cons.h>
119
120#include "locators.h"
121
122/*
123 * How many input characters we can buffer.
124 * The port-specific var.h may override this.
125 * Note: must be a power of two!
126 */
127#ifndef	ZSTTY_RING_SIZE
128#define	ZSTTY_RING_SIZE	2048
129#endif
130
131/*
132 * Make this an option variable one can patch.
133 * But be warned:  this must be a power of 2!
134 */
135u_int zstty_rbuf_size = ZSTTY_RING_SIZE;
136
137/* Stop input when 3/4 of the ring is full; restart when only 1/4 is full. */
138u_int zstty_rbuf_hiwat = (ZSTTY_RING_SIZE * 1) / 4;
139u_int zstty_rbuf_lowat = (ZSTTY_RING_SIZE * 3) / 4;
140
141static int zsppscap =
142	PPS_TSFMT_TSPEC |
143	PPS_CAPTUREASSERT |
144	PPS_CAPTURECLEAR |
145#ifdef  PPS_SYNC
146	PPS_HARDPPSONASSERT | PPS_HARDPPSONCLEAR |
147#endif	/* PPS_SYNC */
148	PPS_OFFSETASSERT | PPS_OFFSETCLEAR;
149
150struct zstty_softc {
151	struct	device zst_dev;		/* required first: base device */
152	struct  tty *zst_tty;
153	struct	zs_chanstate *zst_cs;
154
155	u_int zst_overflows,
156	      zst_floods,
157	      zst_errors;
158
159	int zst_hwflags,	/* see z8530var.h */
160	    zst_swflags;	/* TIOCFLAG_SOFTCAR, ... <ttycom.h> */
161
162	u_int zst_r_hiwat,
163	      zst_r_lowat;
164	u_char *volatile zst_rbget,
165	       *volatile zst_rbput;
166	volatile u_int zst_rbavail;
167	u_char *zst_rbuf,
168	       *zst_ebuf;
169
170	/*
171	 * The transmit byte count and address are used for pseudo-DMA
172	 * output in the hardware interrupt code.  PDMA can be suspended
173	 * to get pending changes done; heldtbc is used for this.  It can
174	 * also be stopped for ^S; this sets TS_TTSTOP in tp->t_state.
175	 */
176	u_char *zst_tba;		/* transmit buffer address */
177	u_int zst_tbc,			/* transmit byte count */
178	      zst_heldtbc;		/* held tbc while xmission stopped */
179
180	/* Flags to communicate with zstty_softint() */
181	volatile u_char zst_rx_flags,	/* receiver blocked */
182#define	RX_TTY_BLOCKED		0x01
183#define	RX_TTY_OVERFLOWED	0x02
184#define	RX_IBUF_BLOCKED		0x04
185#define	RX_IBUF_OVERFLOWED	0x08
186#define	RX_ANY_BLOCK		0x0f
187			zst_tx_busy,	/* working on an output chunk */
188			zst_tx_done,	/* done with one output chunk */
189			zst_tx_stopped,	/* H/W level stop (lost CTS) */
190			zst_st_check,	/* got a status interrupt */
191			zst_rx_ready;
192
193	/* PPS signal on DCD, with or without inkernel clock disciplining */
194	u_char  zst_ppsmask;			/* pps signal mask */
195	u_char  zst_ppsassert;			/* pps leading edge */
196	u_char  zst_ppsclear;			/* pps trailing edge */
197	pps_info_t ppsinfo;
198	pps_params_t ppsparam;
199};
200
201/* Macros to clear/set/test flags. */
202#define SET(t, f)	(t) |= (f)
203#define CLR(t, f)	(t) &= ~(f)
204#define ISSET(t, f)	((t) & (f))
205
206/* Definition of the driver for autoconfig. */
207static int	zstty_match(struct device *, struct cfdata *, void *);
208static void	zstty_attach(struct device *, struct device *, void *);
209
210struct cfattach zstty_ca = {
211	sizeof(struct zstty_softc), zstty_match, zstty_attach
212};
213
214extern struct cfdriver zstty_cd;
215
216struct zsops zsops_tty;
217
218/* Routines called from other code. */
219cdev_decl(zs);	/* open, close, read, write, ioctl, stop, ... */
220
221static void zs_shutdown __P((struct zstty_softc *));
222static void	zsstart __P((struct tty *));
223static int	zsparam __P((struct tty *, struct termios *));
224static void zs_modem __P((struct zstty_softc *, int));
225static void tiocm_to_zs __P((struct zstty_softc *, int, int));
226static int  zs_to_tiocm __P((struct zstty_softc *));
227static int    zshwiflow __P((struct tty *, int));
228static void  zs_hwiflow __P((struct zstty_softc *));
229static void zs_maskintr __P((struct zstty_softc *));
230
231/* Low-level routines. */
232static void zstty_rxint   __P((struct zs_chanstate *));
233static void zstty_stint   __P((struct zs_chanstate *, int));
234static void zstty_txint   __P((struct zs_chanstate *));
235static void zstty_softint __P((struct zs_chanstate *));
236
237#define	ZSUNIT(x)	(minor(x) & 0x7ffff)
238#define	ZSDIALOUT(x)	(minor(x) & 0x80000)
239
240/*
241 * zstty_match: how is this zs channel configured?
242 */
243int
244zstty_match(parent, cf, aux)
245	struct device *parent;
246	struct cfdata *cf;
247	void   *aux;
248{
249	struct zsc_attach_args *args = aux;
250
251	/* Exact match is better than wildcard. */
252	if (cf->cf_loc[ZSCCF_CHANNEL] == args->channel)
253		return 2;
254
255	/* This driver accepts wildcard. */
256	if (cf->cf_loc[ZSCCF_CHANNEL] == ZSCCF_CHANNEL_DEFAULT)
257		return 1;
258
259	return 0;
260}
261
262void
263zstty_attach(parent, self, aux)
264	struct device *parent, *self;
265	void   *aux;
266
267{
268	struct zsc_softc *zsc = (void *) parent;
269	struct zstty_softc *zst = (void *) self;
270	struct cfdata *cf = self->dv_cfdata;
271	struct zsc_attach_args *args = aux;
272	struct zs_chanstate *cs;
273	struct tty *tp;
274	int channel, s, tty_unit;
275	dev_t dev;
276	char *i, *o;
277
278	tty_unit = zst->zst_dev.dv_unit;
279	channel = args->channel;
280	cs = zsc->zsc_cs[channel];
281	cs->cs_private = zst;
282	cs->cs_ops = &zsops_tty;
283
284	zst->zst_cs = cs;
285	zst->zst_swflags = cf->cf_flags;	/* softcar, etc. */
286	zst->zst_hwflags = args->hwflags;
287	dev = makedev(zs_major, tty_unit);
288
289	if (zst->zst_swflags)
290		printf(" flags 0x%x", zst->zst_swflags);
291
292	/*
293	 * Check whether we serve as a console device.
294	 * XXX - split console input/output channels aren't
295	 *	 supported yet on /dev/console
296	 */
297	i = o = NULL;
298	if ((zst->zst_hwflags & ZS_HWFLAG_CONSOLE_INPUT) != 0) {
299		i = "input";
300		if ((args->hwflags & ZS_HWFLAG_USE_CONSDEV) != 0) {
301			cn_tab->cn_pollc = args->consdev->cn_pollc;
302			cn_tab->cn_getc = args->consdev->cn_getc;
303		}
304		cn_tab->cn_dev = dev;
305	}
306	if ((zst->zst_hwflags & ZS_HWFLAG_CONSOLE_OUTPUT) != 0) {
307		o = "output";
308		if ((args->hwflags & ZS_HWFLAG_USE_CONSDEV) != 0) {
309			cn_tab->cn_putc = args->consdev->cn_putc;
310		}
311		cn_tab->cn_dev = dev;
312	}
313	if (i != NULL || o != NULL)
314		printf(" (console %s)", i ? (o ? "i/o" : i) : o);
315
316#ifdef KGDB
317	if (zs_check_kgdb(cs, dev)) {
318		/*
319		 * Allow kgdb to "take over" this port.  Returns true
320		 * if this serial port is in-use by kgdb.
321		 */
322		printf(" (kgdb)");
323		/*
324		 * This is the kgdb port (exclusive use)
325		 * so skip the normal attach code.
326		 */
327		return;
328	}
329#endif
330	printf("\n");
331
332	tp = ttymalloc();
333	tp->t_dev = dev;
334	tp->t_oproc = zsstart;
335	tp->t_param = zsparam;
336	tp->t_hwiflow = zshwiflow;
337	tty_attach(tp);
338
339	zst->zst_tty = tp;
340	zst->zst_rbuf = malloc(zstty_rbuf_size << 1, M_DEVBUF, M_WAITOK);
341	zst->zst_ebuf = zst->zst_rbuf + (zstty_rbuf_size << 1);
342	/* Disable the high water mark. */
343	zst->zst_r_hiwat = 0;
344	zst->zst_r_lowat = 0;
345	zst->zst_rbget = zst->zst_rbput = zst->zst_rbuf;
346	zst->zst_rbavail = zstty_rbuf_size;
347
348	/* if there are no enable/disable functions, assume the device
349	   is always enabled */
350	if (!cs->enable)
351		cs->enabled = 1;
352
353	/*
354	 * Hardware init
355	 */
356	if (ISSET(zst->zst_hwflags, ZS_HWFLAG_CONSOLE)) {
357		/* Call zsparam similar to open. */
358		struct termios t;
359
360		/* Setup the "new" parameters in t. */
361		t.c_ispeed = 0;
362		t.c_ospeed = cs->cs_defspeed;
363		t.c_cflag = cs->cs_defcflag;
364
365		s = splzs();
366
367		/*
368		 * Turn on receiver and status interrupts.
369		 * We defer the actual write of the register to zsparam(),
370		 * but we must make sure status interrupts are turned on by
371		 * the time zsparam() reads the initial rr0 state.
372		 */
373		SET(cs->cs_preg[1], ZSWR1_RIE | ZSWR1_SIE);
374
375		splx(s);
376
377		/* Make sure zsparam will see changes. */
378		tp->t_ospeed = 0;
379		(void) zsparam(tp, &t);
380
381		s = splzs();
382
383		/* Make sure DTR is on now. */
384		zs_modem(zst, 1);
385
386		splx(s);
387	} else {
388		/* Not the console; may need reset. */
389		int reset;
390
391		reset = (channel == 0) ? ZSWR9_A_RESET : ZSWR9_B_RESET;
392
393		s = splzs();
394
395		zs_write_reg(cs, 9, reset);
396
397		/* Will raise DTR in open. */
398		zs_modem(zst, 0);
399
400		splx(s);
401	}
402}
403
404
405/*
406 * Return pointer to our tty.
407 */
408struct tty *
409zstty(dev)
410	dev_t dev;
411{
412	struct zstty_softc *zst;
413	int unit = ZSUNIT(dev);
414
415#ifdef	DIAGNOSTIC
416	if (unit >= zstty_cd.cd_ndevs)
417		panic("zstty");
418#endif
419	zst = zstty_cd.cd_devs[unit];
420	return (zst->zst_tty);
421}
422
423
424void
425zs_shutdown(zst)
426	struct zstty_softc *zst;
427{
428	struct zs_chanstate *cs = zst->zst_cs;
429	struct tty *tp = zst->zst_tty;
430	int s;
431
432	s = splzs();
433
434	/* If we were asserting flow control, then deassert it. */
435	SET(zst->zst_rx_flags, RX_IBUF_BLOCKED);
436	zs_hwiflow(zst);
437
438	/* Clear any break condition set with TIOCSBRK. */
439	zs_break(cs, 0);
440
441	/* Turn off PPS capture on last close. */
442	zst->zst_ppsmask = 0;
443	zst->ppsparam.mode = 0;
444
445	/*
446	 * Hang up if necessary.  Wait a bit, so the other side has time to
447	 * notice even if we immediately open the port again.
448	 */
449	if (ISSET(tp->t_cflag, HUPCL)) {
450		zs_modem(zst, 0);
451		(void) tsleep(cs, TTIPRI, ttclos, hz);
452	}
453
454	/* Turn off interrupts if not the console. */
455	if (!ISSET(zst->zst_hwflags, ZS_HWFLAG_CONSOLE)) {
456		CLR(cs->cs_preg[1], ZSWR1_RIE | ZSWR1_SIE);
457		cs->cs_creg[1] = cs->cs_preg[1];
458		zs_write_reg(cs, 1, cs->cs_creg[1]);
459	}
460
461	/* Call the power management hook. */
462	if (cs->disable) {
463#ifdef DIAGNOSTIC
464		if (!cs->enabled)
465			panic("zs_shutdown: not enabled?");
466#endif
467		(*cs->disable)(zst->zst_cs);
468	}
469
470	splx(s);
471}
472
473/*
474 * Open a zs serial (tty) port.
475 */
476int
477zsopen(dev, flags, mode, p)
478	dev_t dev;
479	int flags;
480	int mode;
481	struct proc *p;
482{
483	int unit = ZSUNIT(dev);
484	struct zstty_softc *zst;
485	struct zs_chanstate *cs;
486	struct tty *tp;
487	int s, s2;
488	int error;
489
490	if (unit >= zstty_cd.cd_ndevs)
491		return (ENXIO);
492	zst = zstty_cd.cd_devs[unit];
493	if (zst == 0)
494		return (ENXIO);
495	tp = zst->zst_tty;
496	cs = zst->zst_cs;
497
498	/* If KGDB took the line, then tp==NULL */
499	if (tp == NULL)
500		return (EBUSY);
501
502	if (ISSET(tp->t_state, TS_ISOPEN) &&
503	    ISSET(tp->t_state, TS_XCLUDE) &&
504	    p->p_ucred->cr_uid != 0)
505		return (EBUSY);
506
507	s = spltty();
508
509	/*
510	 * Do the following iff this is a first open.
511	 */
512	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
513		struct termios t;
514
515		tp->t_dev = dev;
516
517		/* Call the power management hook. */
518		if (cs->enable) {
519			if ((*cs->enable)(cs)) {
520				splx(s2);
521				splx(s);
522				printf("%s: device enable failed\n",
523			       	zst->zst_dev.dv_xname);
524				return (EIO);
525			}
526		}
527
528		/*
529		 * Initialize the termios status to the defaults.  Add in the
530		 * sticky bits from TIOCSFLAGS.
531		 */
532		t.c_ispeed = 0;
533		t.c_ospeed = cs->cs_defspeed;
534		t.c_cflag = cs->cs_defcflag;
535		if (ISSET(zst->zst_swflags, TIOCFLAG_CLOCAL))
536			SET(t.c_cflag, CLOCAL);
537		if (ISSET(zst->zst_swflags, TIOCFLAG_CRTSCTS))
538			SET(t.c_cflag, CRTSCTS);
539		if (ISSET(zst->zst_swflags, TIOCFLAG_CDTRCTS))
540			SET(t.c_cflag, CDTRCTS);
541		if (ISSET(zst->zst_swflags, TIOCFLAG_MDMBUF))
542			SET(t.c_cflag, MDMBUF);
543
544		s2 = splzs();
545
546		/*
547		 * Turn on receiver and status interrupts.
548		 * We defer the actual write of the register to zsparam(),
549		 * but we must make sure status interrupts are turned on by
550		 * the time zsparam() reads the initial rr0 state.
551		 */
552		SET(cs->cs_preg[1], ZSWR1_RIE | ZSWR1_SIE);
553
554		/* Clear PPS capture state on first open. */
555		zst->zst_ppsmask = 0;
556		zst->ppsparam.mode = 0;
557
558		splx(s2);
559
560		/* Make sure zsparam will see changes. */
561		tp->t_ospeed = 0;
562		(void) zsparam(tp, &t);
563
564		/*
565		 * Note: zsparam has done: cflag, ispeed, ospeed
566		 * so we just need to do: iflag, oflag, lflag, cc
567		 * For "raw" mode, just leave all zeros.
568		 */
569		if (!ISSET(zst->zst_hwflags, ZS_HWFLAG_RAW)) {
570			tp->t_iflag = TTYDEF_IFLAG;
571			tp->t_oflag = TTYDEF_OFLAG;
572			tp->t_lflag = TTYDEF_LFLAG;
573		} else {
574			tp->t_iflag = 0;
575			tp->t_oflag = 0;
576			tp->t_lflag = 0;
577		}
578		ttychars(tp);
579		ttsetwater(tp);
580
581		s2 = splzs();
582
583		/*
584		 * Turn on DTR.  We must always do this, even if carrier is not
585		 * present, because otherwise we'd have to use TIOCSDTR
586		 * immediately after setting CLOCAL, which applications do not
587		 * expect.  We always assert DTR while the device is open
588		 * unless explicitly requested to deassert it.
589		 */
590		zs_modem(zst, 1);
591
592		/* Clear the input ring, and unblock. */
593		zst->zst_rbget = zst->zst_rbput = zst->zst_rbuf;
594		zst->zst_rbavail = zstty_rbuf_size;
595		zs_iflush(cs);
596		CLR(zst->zst_rx_flags, RX_ANY_BLOCK);
597		zs_hwiflow(zst);
598
599		splx(s2);
600	}
601
602	splx(s);
603
604	error = ttyopen(tp, ZSDIALOUT(dev), ISSET(flags, O_NONBLOCK));
605	if (error)
606		goto bad;
607
608	error = (*linesw[tp->t_line].l_open)(dev, tp);
609	if (error)
610		goto bad;
611
612	return (0);
613
614bad:
615	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
616		/*
617		 * We failed to open the device, and nobody else had it opened.
618		 * Clean up the state as appropriate.
619		 */
620		zs_shutdown(zst);
621	}
622
623	return (error);
624}
625
626/*
627 * Close a zs serial port.
628 */
629int
630zsclose(dev, flags, mode, p)
631	dev_t dev;
632	int flags;
633	int mode;
634	struct proc *p;
635{
636	struct zstty_softc *zst = zstty_cd.cd_devs[ZSUNIT(dev)];
637	struct tty *tp = zst->zst_tty;
638
639	/* XXX This is for cons.c. */
640	if (!ISSET(tp->t_state, TS_ISOPEN))
641		return 0;
642
643	(*linesw[tp->t_line].l_close)(tp, flags);
644	ttyclose(tp);
645
646	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
647		/*
648		 * Although we got a last close, the device may still be in
649		 * use; e.g. if this was the dialout node, and there are still
650		 * processes waiting for carrier on the non-dialout node.
651		 */
652		zs_shutdown(zst);
653	}
654
655	return (0);
656}
657
658/*
659 * Read/write zs serial port.
660 */
661int
662zsread(dev, uio, flags)
663	dev_t dev;
664	struct uio *uio;
665	int flags;
666{
667	struct zstty_softc *zst = zstty_cd.cd_devs[ZSUNIT(dev)];
668	struct tty *tp = zst->zst_tty;
669
670	return ((*linesw[tp->t_line].l_read)(tp, uio, flags));
671}
672
673int
674zswrite(dev, uio, flags)
675	dev_t dev;
676	struct uio *uio;
677	int flags;
678{
679	struct zstty_softc *zst = zstty_cd.cd_devs[ZSUNIT(dev)];
680	struct tty *tp = zst->zst_tty;
681
682	return ((*linesw[tp->t_line].l_write)(tp, uio, flags));
683}
684
685int
686zsioctl(dev, cmd, data, flag, p)
687	dev_t dev;
688	u_long cmd;
689	caddr_t data;
690	int flag;
691	struct proc *p;
692{
693	struct zstty_softc *zst = zstty_cd.cd_devs[ZSUNIT(dev)];
694	struct zs_chanstate *cs = zst->zst_cs;
695	struct tty *tp = zst->zst_tty;
696	int error;
697	int s;
698
699	error = (*linesw[tp->t_line].l_ioctl)(tp, cmd, data, flag, p);
700	if (error >= 0)
701		return (error);
702
703	error = ttioctl(tp, cmd, data, flag, p);
704	if (error >= 0)
705		return (error);
706
707#ifdef	ZS_MD_IOCTL
708	error = ZS_MD_IOCTL;
709	if (error >= 0)
710		return (error);
711#endif	/* ZS_MD_IOCTL */
712
713	error = 0;
714
715	s = splzs();
716
717	switch (cmd) {
718	case TIOCSBRK:
719		zs_break(cs, 1);
720		break;
721
722	case TIOCCBRK:
723		zs_break(cs, 0);
724		break;
725
726	case TIOCGFLAGS:
727		*(int *)data = zst->zst_swflags;
728		break;
729
730	case TIOCSFLAGS:
731		error = suser(p->p_ucred, &p->p_acflag);
732		if (error)
733			break;
734		zst->zst_swflags = *(int *)data;
735		break;
736
737	case TIOCSDTR:
738		zs_modem(zst, 1);
739		break;
740
741	case TIOCCDTR:
742		zs_modem(zst, 0);
743		break;
744
745	case TIOCMSET:
746	case TIOCMBIS:
747	case TIOCMBIC:
748		tiocm_to_zs(zst, cmd, *(int *)data);
749		break;
750
751	case TIOCMGET:
752		*(int *)data = zs_to_tiocm(zst);
753		break;
754
755	case PPS_IOC_CREATE:
756		break;
757
758	case PPS_IOC_DESTROY:
759		break;
760
761	case PPS_IOC_GETPARAMS: {
762		pps_params_t *pp;
763		pp = (pps_params_t *)data;
764		*pp = zst->ppsparam;
765		break;
766	}
767
768	case PPS_IOC_SETPARAMS: {
769		pps_params_t *pp;
770		int mode;
771		if (cs->cs_rr0_pps == 0) {
772			error = EINVAL;
773			break;
774		}
775		pp = (pps_params_t *)data;
776		if (pp->mode & ~zsppscap) {
777			error = EINVAL;
778			break;
779		}
780		zst->ppsparam = *pp;
781		/*
782		 * compute masks from user-specified timestamp state.
783		 */
784		mode = zst->ppsparam.mode;
785#ifdef	PPS_SYNC
786		if (mode & PPS_HARDPPSONASSERT) {
787			mode |= PPS_CAPTUREASSERT;
788			/* XXX revoke any previous HARDPPS source */
789		}
790		if (mode & PPS_HARDPPSONCLEAR) {
791			mode |= PPS_CAPTURECLEAR;
792			/* XXX revoke any previous HARDPPS source */
793		}
794#endif	/* PPS_SYNC */
795		switch (mode & PPS_CAPTUREBOTH) {
796		case 0:
797			zst->zst_ppsmask = 0;
798			break;
799
800		case PPS_CAPTUREASSERT:
801			zst->zst_ppsmask = ZSRR0_DCD;
802			zst->zst_ppsassert = ZSRR0_DCD;
803			zst->zst_ppsclear = -1;
804			break;
805
806		case PPS_CAPTURECLEAR:
807			zst->zst_ppsmask = ZSRR0_DCD;
808			zst->zst_ppsassert = -1;
809			zst->zst_ppsclear = 0;
810			break;
811
812		case PPS_CAPTUREBOTH:
813			zst->zst_ppsmask = ZSRR0_DCD;
814			zst->zst_ppsassert = ZSRR0_DCD;
815			zst->zst_ppsclear = 0;
816			break;
817
818		default:
819			error = EINVAL;
820			break;
821		}
822
823		/*
824		 * Now update interrupts.
825		 */
826		zs_maskintr(zst);
827		/*
828		 * If nothing is being transmitted, set up new current values,
829		 * else mark them as pending.
830		 */
831		if (!cs->cs_heldchange) {
832			if (zst->zst_tx_busy) {
833				zst->zst_heldtbc = zst->zst_tbc;
834				zst->zst_tbc = 0;
835				cs->cs_heldchange = 1;
836			} else
837				zs_loadchannelregs(cs);
838		}
839
840		break;
841	}
842
843	case PPS_IOC_GETCAP:
844		*(int *)data = zsppscap;
845		break;
846
847	case PPS_IOC_FETCH: {
848		pps_info_t *pi;
849		pi = (pps_info_t *)data;
850		*pi = zst->ppsinfo;
851		break;
852	}
853
854	case TIOCDCDTIMESTAMP:	/* XXX old, overloaded  API used by xntpd v3 */
855		if (cs->cs_rr0_pps == 0) {
856			error = EINVAL;
857			break;
858		}
859		/*
860		 * Some GPS clocks models use the falling rather than
861		 * rising edge as the on-the-second signal.
862		 * The old API has no way to specify PPS polarity.
863		 */
864		zst->zst_ppsmask = ZSRR0_DCD;
865#ifndef	PPS_TRAILING_EDGE
866		zst->zst_ppsassert = ZSRR0_DCD;
867		zst->zst_ppsclear = -1;
868		TIMESPEC_TO_TIMEVAL((struct timeval *)data,
869			&zst->ppsinfo.assert_timestamp);
870#else
871		zst->zst_ppsassert = -1;
872		zst->zst_ppsclear = 01;
873		TIMESPEC_TO_TIMEVAL((struct timeval *)data,
874			&zst->ppsinfo.clear_timestamp);
875#endif
876		/*
877		 * Now update interrupts.
878		 */
879		zs_maskintr(zst);
880		/*
881		 * If nothing is being transmitted, set up new current values,
882		 * else mark them as pending.
883		 */
884		if (!cs->cs_heldchange) {
885			if (zst->zst_tx_busy) {
886				zst->zst_heldtbc = zst->zst_tbc;
887				zst->zst_tbc = 0;
888				cs->cs_heldchange = 1;
889			} else
890				zs_loadchannelregs(cs);
891		}
892
893		break;
894
895	default:
896		error = ENOTTY;
897		break;
898	}
899
900	splx(s);
901
902	return (error);
903}
904
905/*
906 * Start or restart transmission.
907 */
908static void
909zsstart(tp)
910	struct tty *tp;
911{
912	struct zstty_softc *zst = zstty_cd.cd_devs[ZSUNIT(tp->t_dev)];
913	struct zs_chanstate *cs = zst->zst_cs;
914	int s;
915
916	s = spltty();
917	if (ISSET(tp->t_state, TS_BUSY | TS_TIMEOUT | TS_TTSTOP))
918		goto out;
919	if (zst->zst_tx_stopped)
920		goto out;
921
922	if (tp->t_outq.c_cc <= tp->t_lowat) {
923		if (ISSET(tp->t_state, TS_ASLEEP)) {
924			CLR(tp->t_state, TS_ASLEEP);
925			wakeup((caddr_t)&tp->t_outq);
926		}
927		selwakeup(&tp->t_wsel);
928		if (tp->t_outq.c_cc == 0)
929			goto out;
930	}
931
932	/* Grab the first contiguous region of buffer space. */
933	{
934		u_char *tba;
935		int tbc;
936
937		tba = tp->t_outq.c_cf;
938		tbc = ndqb(&tp->t_outq, 0);
939
940		(void) splzs();
941
942		zst->zst_tba = tba;
943		zst->zst_tbc = tbc;
944	}
945
946	SET(tp->t_state, TS_BUSY);
947	zst->zst_tx_busy = 1;
948
949	/* Enable transmit completion interrupts if necessary. */
950	if (!ISSET(cs->cs_preg[1], ZSWR1_TIE)) {
951		SET(cs->cs_preg[1], ZSWR1_TIE);
952		cs->cs_creg[1] = cs->cs_preg[1];
953		zs_write_reg(cs, 1, cs->cs_creg[1]);
954	}
955
956	/* Output the first character of the contiguous buffer. */
957	{
958		zs_write_data(cs, *zst->zst_tba);
959		zst->zst_tbc--;
960		zst->zst_tba++;
961	}
962out:
963	splx(s);
964	return;
965}
966
967/*
968 * Stop output, e.g., for ^S or output flush.
969 */
970void
971zsstop(tp, flag)
972	struct tty *tp;
973	int flag;
974{
975	struct zstty_softc *zst = zstty_cd.cd_devs[ZSUNIT(tp->t_dev)];
976	int s;
977
978	s = splzs();
979	if (ISSET(tp->t_state, TS_BUSY)) {
980		/* Stop transmitting at the next chunk. */
981		zst->zst_tbc = 0;
982		zst->zst_heldtbc = 0;
983		if (!ISSET(tp->t_state, TS_TTSTOP))
984			SET(tp->t_state, TS_FLUSH);
985	}
986	splx(s);
987}
988
989/*
990 * Set ZS tty parameters from termios.
991 * XXX - Should just copy the whole termios after
992 * making sure all the changes could be done.
993 */
994static int
995zsparam(tp, t)
996	struct tty *tp;
997	struct termios *t;
998{
999	struct zstty_softc *zst = zstty_cd.cd_devs[ZSUNIT(tp->t_dev)];
1000	struct zs_chanstate *cs = zst->zst_cs;
1001	int ospeed, cflag;
1002	u_char tmp3, tmp4, tmp5;
1003	int s, error;
1004
1005	ospeed = t->c_ospeed;
1006	cflag = t->c_cflag;
1007
1008	/* Check requested parameters. */
1009	if (ospeed < 0)
1010		return (EINVAL);
1011	if (t->c_ispeed && t->c_ispeed != ospeed)
1012		return (EINVAL);
1013
1014	/*
1015	 * For the console, always force CLOCAL and !HUPCL, so that the port
1016	 * is always active.
1017	 */
1018	if (ISSET(zst->zst_swflags, TIOCFLAG_SOFTCAR) ||
1019	    ISSET(zst->zst_hwflags, ZS_HWFLAG_CONSOLE)) {
1020		SET(cflag, CLOCAL);
1021		CLR(cflag, HUPCL);
1022	}
1023
1024	/*
1025	 * Only whack the UART when params change.
1026	 * Some callers need to clear tp->t_ospeed
1027	 * to make sure initialization gets done.
1028	 */
1029	if (tp->t_ospeed == ospeed &&
1030	    tp->t_cflag == cflag)
1031		return (0);
1032
1033	/*
1034	 * Call MD functions to deal with changed
1035	 * clock modes or H/W flow control modes.
1036	 * The BRG divisor is set now. (reg 12,13)
1037	 */
1038	error = zs_set_speed(cs, ospeed);
1039	if (error)
1040		return (error);
1041	error = zs_set_modes(cs, cflag);
1042	if (error)
1043		return (error);
1044
1045	/*
1046	 * Block interrupts so that state will not
1047	 * be altered until we are done setting it up.
1048	 *
1049	 * Initial values in cs_preg are set before
1050	 * our attach routine is called.  The master
1051	 * interrupt enable is handled by zsc.c
1052	 *
1053	 */
1054	s = splzs();
1055
1056	/*
1057	 * Recalculate which status ints to enable.
1058	 */
1059	zs_maskintr(zst);
1060
1061	/* Recompute character size bits. */
1062	tmp3 = cs->cs_preg[3];
1063	tmp5 = cs->cs_preg[5];
1064	CLR(tmp3, ZSWR3_RXSIZE);
1065	CLR(tmp5, ZSWR5_TXSIZE);
1066	switch (ISSET(cflag, CSIZE)) {
1067	case CS5:
1068		SET(tmp3, ZSWR3_RX_5);
1069		SET(tmp5, ZSWR5_TX_5);
1070		break;
1071	case CS6:
1072		SET(tmp3, ZSWR3_RX_6);
1073		SET(tmp5, ZSWR5_TX_6);
1074		break;
1075	case CS7:
1076		SET(tmp3, ZSWR3_RX_7);
1077		SET(tmp5, ZSWR5_TX_7);
1078		break;
1079	case CS8:
1080		SET(tmp3, ZSWR3_RX_8);
1081		SET(tmp5, ZSWR5_TX_8);
1082		break;
1083	}
1084	cs->cs_preg[3] = tmp3;
1085	cs->cs_preg[5] = tmp5;
1086
1087	/*
1088	 * Recompute the stop bits and parity bits.  Note that
1089	 * zs_set_speed() may have set clock selection bits etc.
1090	 * in wr4, so those must preserved.
1091	 */
1092	tmp4 = cs->cs_preg[4];
1093	CLR(tmp4, ZSWR4_SBMASK | ZSWR4_PARMASK);
1094	if (ISSET(cflag, CSTOPB))
1095		SET(tmp4, ZSWR4_TWOSB);
1096	else
1097		SET(tmp4, ZSWR4_ONESB);
1098	if (!ISSET(cflag, PARODD))
1099		SET(tmp4, ZSWR4_EVENP);
1100	if (ISSET(cflag, PARENB))
1101		SET(tmp4, ZSWR4_PARENB);
1102	cs->cs_preg[4] = tmp4;
1103
1104	/* And copy to tty. */
1105	tp->t_ispeed = 0;
1106	tp->t_ospeed = ospeed;
1107	tp->t_cflag = cflag;
1108
1109	/*
1110	 * If nothing is being transmitted, set up new current values,
1111	 * else mark them as pending.
1112	 */
1113	if (!cs->cs_heldchange) {
1114		if (zst->zst_tx_busy) {
1115			zst->zst_heldtbc = zst->zst_tbc;
1116			zst->zst_tbc = 0;
1117			cs->cs_heldchange = 1;
1118		} else
1119			zs_loadchannelregs(cs);
1120	}
1121
1122	/*
1123	 * If hardware flow control is disabled, turn off the buffer water
1124	 * marks and unblock any soft flow control state.  Otherwise, enable
1125	 * the water marks.
1126	 */
1127	if (!ISSET(cflag, CHWFLOW)) {
1128		zst->zst_r_hiwat = 0;
1129		zst->zst_r_lowat = 0;
1130		if (ISSET(zst->zst_rx_flags, RX_TTY_OVERFLOWED)) {
1131			CLR(zst->zst_rx_flags, RX_TTY_OVERFLOWED);
1132			zst->zst_rx_ready = 1;
1133			cs->cs_softreq = 1;
1134		}
1135		if (ISSET(zst->zst_rx_flags, RX_TTY_BLOCKED|RX_IBUF_BLOCKED)) {
1136			CLR(zst->zst_rx_flags, RX_TTY_BLOCKED|RX_IBUF_BLOCKED);
1137			zs_hwiflow(zst);
1138		}
1139	} else {
1140		zst->zst_r_hiwat = zstty_rbuf_hiwat;
1141		zst->zst_r_lowat = zstty_rbuf_lowat;
1142	}
1143
1144	/*
1145	 * Force a recheck of the hardware carrier and flow control status,
1146	 * since we may have changed which bits we're looking at.
1147	 */
1148	zstty_stint(cs, 1);
1149
1150	splx(s);
1151
1152	/*
1153	 * If hardware flow control is disabled, unblock any hard flow control
1154	 * state.
1155	 */
1156	if (!ISSET(cflag, CHWFLOW)) {
1157		if (zst->zst_tx_stopped) {
1158			zst->zst_tx_stopped = 0;
1159			zsstart(tp);
1160		}
1161	}
1162
1163	zstty_softint(cs);
1164
1165	return (0);
1166}
1167
1168/*
1169 * Compute interupt enable bits and set in the pending bits. Called both
1170 * in zsparam() and when PPS (pulse per second timing) state changes.
1171 * Must be called at splzs().
1172 */
1173static void
1174zs_maskintr(zst)
1175	struct zstty_softc *zst;
1176{
1177	struct zs_chanstate *cs = zst->zst_cs;
1178	int tmp15;
1179
1180	cs->cs_rr0_mask = cs->cs_rr0_cts | cs->cs_rr0_dcd;
1181	if (zst->zst_ppsmask != 0)
1182		cs->cs_rr0_mask |= cs->cs_rr0_pps;
1183	tmp15 = cs->cs_preg[15];
1184	if (ISSET(cs->cs_rr0_mask, ZSRR0_DCD))
1185		SET(tmp15, ZSWR15_DCD_IE);
1186	else
1187		CLR(tmp15, ZSWR15_DCD_IE);
1188	if (ISSET(cs->cs_rr0_mask, ZSRR0_CTS))
1189		SET(tmp15, ZSWR15_CTS_IE);
1190	else
1191		CLR(tmp15, ZSWR15_CTS_IE);
1192	cs->cs_preg[15] = tmp15;
1193}
1194
1195
1196/*
1197 * Raise or lower modem control (DTR/RTS) signals.  If a character is
1198 * in transmission, the change is deferred.
1199 */
1200static void
1201zs_modem(zst, onoff)
1202	struct zstty_softc *zst;
1203	int onoff;
1204{
1205	struct zs_chanstate *cs = zst->zst_cs;
1206
1207	if (cs->cs_wr5_dtr == 0)
1208		return;
1209
1210	if (onoff)
1211		SET(cs->cs_preg[5], cs->cs_wr5_dtr);
1212	else
1213		CLR(cs->cs_preg[5], cs->cs_wr5_dtr);
1214
1215	if (!cs->cs_heldchange) {
1216		if (zst->zst_tx_busy) {
1217			zst->zst_heldtbc = zst->zst_tbc;
1218			zst->zst_tbc = 0;
1219			cs->cs_heldchange = 1;
1220		} else
1221			zs_loadchannelregs(cs);
1222	}
1223}
1224
1225static void
1226tiocm_to_zs(zst, how, ttybits)
1227	struct zstty_softc *zst;
1228	int how, ttybits;
1229{
1230	struct zs_chanstate *cs = zst->zst_cs;
1231	u_char zsbits;
1232
1233	zsbits = 0;
1234	if (ISSET(ttybits, TIOCM_DTR))
1235		SET(zsbits, ZSWR5_DTR);
1236	if (ISSET(ttybits, TIOCM_RTS))
1237		SET(zsbits, ZSWR5_RTS);
1238
1239	switch (how) {
1240	case TIOCMBIC:
1241		CLR(cs->cs_preg[5], zsbits);
1242		break;
1243
1244	case TIOCMBIS:
1245		SET(cs->cs_preg[5], zsbits);
1246		break;
1247
1248	case TIOCMSET:
1249		CLR(cs->cs_preg[5], ZSWR5_RTS | ZSWR5_DTR);
1250		SET(cs->cs_preg[5], zsbits);
1251		break;
1252	}
1253
1254	if (!cs->cs_heldchange) {
1255		if (zst->zst_tx_busy) {
1256			zst->zst_heldtbc = zst->zst_tbc;
1257			zst->zst_tbc = 0;
1258			cs->cs_heldchange = 1;
1259		} else
1260			zs_loadchannelregs(cs);
1261	}
1262}
1263
1264static int
1265zs_to_tiocm(zst)
1266	struct zstty_softc *zst;
1267{
1268	struct zs_chanstate *cs = zst->zst_cs;
1269	u_char zsbits;
1270	int ttybits = 0;
1271
1272	zsbits = cs->cs_preg[5];
1273	if (ISSET(zsbits, ZSWR5_DTR))
1274		SET(ttybits, TIOCM_DTR);
1275	if (ISSET(zsbits, ZSWR5_RTS))
1276		SET(ttybits, TIOCM_RTS);
1277
1278	zsbits = cs->cs_rr0;
1279	if (ISSET(zsbits, ZSRR0_DCD))
1280		SET(ttybits, TIOCM_CD);
1281	if (ISSET(zsbits, ZSRR0_CTS))
1282		SET(ttybits, TIOCM_CTS);
1283
1284	return (ttybits);
1285}
1286
1287/*
1288 * Try to block or unblock input using hardware flow-control.
1289 * This is called by kern/tty.c if MDMBUF|CRTSCTS is set, and
1290 * if this function returns non-zero, the TS_TBLOCK flag will
1291 * be set or cleared according to the "block" arg passed.
1292 */
1293int
1294zshwiflow(tp, block)
1295	struct tty *tp;
1296	int block;
1297{
1298	struct zstty_softc *zst = zstty_cd.cd_devs[ZSUNIT(tp->t_dev)];
1299	struct zs_chanstate *cs = zst->zst_cs;
1300	int s;
1301
1302	if (cs->cs_wr5_rts == 0)
1303		return (0);
1304
1305	s = splzs();
1306	if (block) {
1307		if (!ISSET(zst->zst_rx_flags, RX_TTY_BLOCKED)) {
1308			SET(zst->zst_rx_flags, RX_TTY_BLOCKED);
1309			zs_hwiflow(zst);
1310		}
1311	} else {
1312		if (ISSET(zst->zst_rx_flags, RX_TTY_OVERFLOWED)) {
1313			CLR(zst->zst_rx_flags, RX_TTY_OVERFLOWED);
1314			zst->zst_rx_ready = 1;
1315			cs->cs_softreq = 1;
1316		}
1317		if (ISSET(zst->zst_rx_flags, RX_TTY_BLOCKED)) {
1318			CLR(zst->zst_rx_flags, RX_TTY_BLOCKED);
1319			zs_hwiflow(zst);
1320		}
1321	}
1322	splx(s);
1323	return (1);
1324}
1325
1326/*
1327 * Internal version of zshwiflow
1328 * called at splzs
1329 */
1330static void
1331zs_hwiflow(zst)
1332	struct zstty_softc *zst;
1333{
1334	struct zs_chanstate *cs = zst->zst_cs;
1335
1336	if (cs->cs_wr5_rts == 0)
1337		return;
1338
1339	if (ISSET(zst->zst_rx_flags, RX_ANY_BLOCK)) {
1340		CLR(cs->cs_preg[5], cs->cs_wr5_rts);
1341		CLR(cs->cs_creg[5], cs->cs_wr5_rts);
1342	} else {
1343		SET(cs->cs_preg[5], cs->cs_wr5_rts);
1344		SET(cs->cs_creg[5], cs->cs_wr5_rts);
1345	}
1346	zs_write_reg(cs, 5, cs->cs_creg[5]);
1347}
1348
1349
1350/****************************************************************
1351 * Interface to the lower layer (zscc)
1352 ****************************************************************/
1353
1354#define	integrate	static inline
1355integrate void zstty_rxsoft __P((struct zstty_softc *, struct tty *));
1356integrate void zstty_txsoft __P((struct zstty_softc *, struct tty *));
1357integrate void zstty_stsoft __P((struct zstty_softc *, struct tty *));
1358static void zstty_diag __P((void *));
1359
1360/*
1361 * receiver ready interrupt.
1362 * called at splzs
1363 */
1364static void
1365zstty_rxint(cs)
1366	struct zs_chanstate *cs;
1367{
1368	struct zstty_softc *zst = cs->cs_private;
1369	u_char *put, *end;
1370	u_int cc;
1371	u_char rr0, rr1, c;
1372
1373	end = zst->zst_ebuf;
1374	put = zst->zst_rbput;
1375	cc = zst->zst_rbavail;
1376
1377	while (cc > 0) {
1378		/*
1379		 * First read the status, because reading the received char
1380		 * destroys the status of this char.
1381		 */
1382		rr1 = zs_read_reg(cs, 1);
1383		c = zs_read_data(cs);
1384
1385		if (ISSET(rr1, ZSRR1_FE | ZSRR1_DO | ZSRR1_PE)) {
1386			/* Clear the receive error. */
1387			zs_write_csr(cs, ZSWR0_RESET_ERRORS);
1388		}
1389
1390		put[0] = c;
1391		put[1] = rr1;
1392		put += 2;
1393		if (put >= end)
1394			put = zst->zst_rbuf;
1395		cc--;
1396
1397		rr0 = zs_read_csr(cs);
1398		if (!ISSET(rr0, ZSRR0_RX_READY))
1399			break;
1400	}
1401
1402	/*
1403	 * Current string of incoming characters ended because
1404	 * no more data was available or we ran out of space.
1405	 * Schedule a receive event if any data was received.
1406	 * If we're out of space, turn off receive interrupts.
1407	 */
1408	zst->zst_rbput = put;
1409	zst->zst_rbavail = cc;
1410	if (!ISSET(zst->zst_rx_flags, RX_TTY_OVERFLOWED)) {
1411		zst->zst_rx_ready = 1;
1412		cs->cs_softreq = 1;
1413	}
1414
1415	/*
1416	 * See if we are in danger of overflowing a buffer. If
1417	 * so, use hardware flow control to ease the pressure.
1418	 */
1419	if (!ISSET(zst->zst_rx_flags, RX_IBUF_BLOCKED) &&
1420	    cc < zst->zst_r_hiwat) {
1421		SET(zst->zst_rx_flags, RX_IBUF_BLOCKED);
1422		zs_hwiflow(zst);
1423	}
1424
1425	/*
1426	 * If we're out of space, disable receive interrupts
1427	 * until the queue has drained a bit.
1428	 */
1429	if (!cc) {
1430		SET(zst->zst_rx_flags, RX_IBUF_OVERFLOWED);
1431		CLR(cs->cs_preg[1], ZSWR1_RIE);
1432		cs->cs_creg[1] = cs->cs_preg[1];
1433		zs_write_reg(cs, 1, cs->cs_creg[1]);
1434	}
1435
1436#if 0
1437	printf("%xH%04d\n", zst->zst_rx_flags, zst->zst_rbavail);
1438#endif
1439}
1440
1441/*
1442 * transmitter ready interrupt.  (splzs)
1443 */
1444static void
1445zstty_txint(cs)
1446	struct zs_chanstate *cs;
1447{
1448	struct zstty_softc *zst = cs->cs_private;
1449
1450	/*
1451	 * If we've delayed a parameter change, do it now, and restart
1452	 * output.
1453	 */
1454	if (cs->cs_heldchange) {
1455		zs_loadchannelregs(cs);
1456		cs->cs_heldchange = 0;
1457		zst->zst_tbc = zst->zst_heldtbc;
1458		zst->zst_heldtbc = 0;
1459	}
1460
1461	/* Output the next character in the buffer, if any. */
1462	if (zst->zst_tbc > 0) {
1463		zs_write_data(cs, *zst->zst_tba);
1464		zst->zst_tbc--;
1465		zst->zst_tba++;
1466	} else {
1467		/* Disable transmit completion interrupts if necessary. */
1468		if (ISSET(cs->cs_preg[1], ZSWR1_TIE)) {
1469			CLR(cs->cs_preg[1], ZSWR1_TIE);
1470			cs->cs_creg[1] = cs->cs_preg[1];
1471			zs_write_reg(cs, 1, cs->cs_creg[1]);
1472		}
1473		if (zst->zst_tx_busy) {
1474			zst->zst_tx_busy = 0;
1475			zst->zst_tx_done = 1;
1476			cs->cs_softreq = 1;
1477		}
1478	}
1479}
1480
1481/*
1482 * status change interrupt.  (splzs)
1483 */
1484static void
1485zstty_stint(cs, force)
1486	struct zs_chanstate *cs;
1487	int force;
1488{
1489	struct zstty_softc *zst = cs->cs_private;
1490	u_char rr0, delta;
1491
1492	rr0 = zs_read_csr(cs);
1493	zs_write_csr(cs, ZSWR0_RESET_STATUS);
1494
1495	/*
1496	 * Check here for console break, so that we can abort
1497	 * even when interrupts are locking up the machine.
1498	 */
1499	if (ISSET(rr0, ZSRR0_BREAK) &&
1500	    ISSET(zst->zst_hwflags, ZS_HWFLAG_CONSOLE_INPUT)) {
1501		zs_abort(cs);
1502		return;
1503	}
1504
1505	if (!force)
1506		delta = rr0 ^ cs->cs_rr0;
1507	else
1508		delta = cs->cs_rr0_mask;
1509	cs->cs_rr0 = rr0;
1510
1511	if (ISSET(delta, cs->cs_rr0_mask)) {
1512		SET(cs->cs_rr0_delta, delta);
1513
1514		/*
1515		 * Pulse-per-second clock signal on edge of DCD?
1516		 */
1517		if (ISSET(delta, zst->zst_ppsmask)) {
1518			struct timeval tv;
1519			if (ISSET(rr0, zst->zst_ppsmask) == zst->zst_ppsassert) {
1520				/* XXX nanotime() */
1521				microtime(&tv);
1522				TIMEVAL_TO_TIMESPEC(&tv,
1523					&zst->ppsinfo.assert_timestamp);
1524				if (zst->ppsparam.mode & PPS_OFFSETASSERT) {
1525					timespecadd(&zst->ppsinfo.assert_timestamp,
1526					    &zst->ppsparam.assert_offset,
1527					    &zst->ppsinfo.assert_timestamp);
1528				}
1529
1530#ifdef PPS_SYNC
1531				if (zst->ppsparam.mode & PPS_HARDPPSONASSERT)
1532					hardpps(&tv, tv.tv_usec);
1533#endif
1534				zst->ppsinfo.assert_sequence++;
1535				zst->ppsinfo.current_mode = zst->ppsparam.mode;
1536			} else if (ISSET(rr0, zst->zst_ppsmask) ==
1537						zst->zst_ppsclear) {
1538				/* XXX nanotime() */
1539				microtime(&tv);
1540				TIMEVAL_TO_TIMESPEC(&tv,
1541					&zst->ppsinfo.clear_timestamp);
1542				if (zst->ppsparam.mode & PPS_OFFSETCLEAR) {
1543					timespecadd(&zst->ppsinfo.clear_timestamp,
1544						&zst->ppsparam.clear_offset,
1545						&zst->ppsinfo.clear_timestamp);
1546				}
1547
1548#ifdef PPS_SYNC
1549				if (zst->ppsparam.mode & PPS_HARDPPSONCLEAR)
1550					hardpps(&tv, tv.tv_usec);
1551#endif
1552				zst->ppsinfo.clear_sequence++;
1553				zst->ppsinfo.current_mode = zst->ppsparam.mode;
1554			}
1555		}
1556
1557		/*
1558		 * Stop output immediately if we lose the output
1559		 * flow control signal or carrier detect.
1560		 */
1561		if (ISSET(~rr0, cs->cs_rr0_mask)) {
1562			zst->zst_tbc = 0;
1563			zst->zst_heldtbc = 0;
1564		}
1565
1566		zst->zst_st_check = 1;
1567		cs->cs_softreq = 1;
1568	}
1569}
1570
1571void
1572zstty_diag(arg)
1573	void *arg;
1574{
1575	struct zstty_softc *zst = arg;
1576	int overflows, floods;
1577	int s;
1578
1579	s = splzs();
1580	overflows = zst->zst_overflows;
1581	zst->zst_overflows = 0;
1582	floods = zst->zst_floods;
1583	zst->zst_floods = 0;
1584	zst->zst_errors = 0;
1585	splx(s);
1586
1587	log(LOG_WARNING, "%s: %d silo overflow%s, %d ibuf flood%s\n",
1588	    zst->zst_dev.dv_xname,
1589	    overflows, overflows == 1 ? "" : "s",
1590	    floods, floods == 1 ? "" : "s");
1591}
1592
1593integrate void
1594zstty_rxsoft(zst, tp)
1595	struct zstty_softc *zst;
1596	struct tty *tp;
1597{
1598	struct zs_chanstate *cs = zst->zst_cs;
1599	int (*rint) __P((int c, struct tty *tp)) = linesw[tp->t_line].l_rint;
1600	u_char *get, *end;
1601	u_int cc, scc;
1602	u_char rr1;
1603	int code;
1604	int s;
1605
1606	end = zst->zst_ebuf;
1607	get = zst->zst_rbget;
1608	scc = cc = zstty_rbuf_size - zst->zst_rbavail;
1609
1610	if (cc == zstty_rbuf_size) {
1611		zst->zst_floods++;
1612		if (zst->zst_errors++ == 0)
1613			timeout(zstty_diag, zst, 60 * hz);
1614	}
1615
1616	/* If not yet open, drop the entire buffer content here */
1617	if (!ISSET(tp->t_state, TS_ISOPEN)) {
1618		get += cc << 1;
1619		if (get >= end)
1620			get -= zstty_rbuf_size << 1;
1621		cc = 0;
1622	}
1623	while (cc) {
1624		code = get[0];
1625		rr1 = get[1];
1626		if (ISSET(rr1, ZSRR1_DO | ZSRR1_FE | ZSRR1_PE)) {
1627			if (ISSET(rr1, ZSRR1_DO)) {
1628				zst->zst_overflows++;
1629				if (zst->zst_errors++ == 0)
1630					timeout(zstty_diag, zst, 60 * hz);
1631			}
1632			if (ISSET(rr1, ZSRR1_FE))
1633				SET(code, TTY_FE);
1634			if (ISSET(rr1, ZSRR1_PE))
1635				SET(code, TTY_PE);
1636		}
1637		if ((*rint)(code, tp) == -1) {
1638			/*
1639			 * The line discipline's buffer is out of space.
1640			 */
1641			if (!ISSET(zst->zst_rx_flags, RX_TTY_BLOCKED)) {
1642				/*
1643				 * We're either not using flow control, or the
1644				 * line discipline didn't tell us to block for
1645				 * some reason.  Either way, we have no way to
1646				 * know when there's more space available, so
1647				 * just drop the rest of the data.
1648				 */
1649				get += cc << 1;
1650				if (get >= end)
1651					get -= zstty_rbuf_size << 1;
1652				cc = 0;
1653			} else {
1654				/*
1655				 * Don't schedule any more receive processing
1656				 * until the line discipline tells us there's
1657				 * space available (through comhwiflow()).
1658				 * Leave the rest of the data in the input
1659				 * buffer.
1660				 */
1661				SET(zst->zst_rx_flags, RX_TTY_OVERFLOWED);
1662			}
1663			break;
1664		}
1665		get += 2;
1666		if (get >= end)
1667			get = zst->zst_rbuf;
1668		cc--;
1669	}
1670
1671	if (cc != scc) {
1672		zst->zst_rbget = get;
1673		s = splzs();
1674		cc = zst->zst_rbavail += scc - cc;
1675		/* Buffers should be ok again, release possible block. */
1676		if (cc >= zst->zst_r_lowat) {
1677			if (ISSET(zst->zst_rx_flags, RX_IBUF_OVERFLOWED)) {
1678				CLR(zst->zst_rx_flags, RX_IBUF_OVERFLOWED);
1679				SET(cs->cs_preg[1], ZSWR1_RIE);
1680				cs->cs_creg[1] = cs->cs_preg[1];
1681				zs_write_reg(cs, 1, cs->cs_creg[1]);
1682			}
1683			if (ISSET(zst->zst_rx_flags, RX_IBUF_BLOCKED)) {
1684				CLR(zst->zst_rx_flags, RX_IBUF_BLOCKED);
1685				zs_hwiflow(zst);
1686			}
1687		}
1688		splx(s);
1689	}
1690
1691#if 0
1692	printf("%xS%04d\n", zst->zst_rx_flags, zst->zst_rbavail);
1693#endif
1694}
1695
1696integrate void
1697zstty_txsoft(zst, tp)
1698	struct zstty_softc *zst;
1699	struct tty *tp;
1700{
1701
1702	CLR(tp->t_state, TS_BUSY);
1703	if (ISSET(tp->t_state, TS_FLUSH))
1704		CLR(tp->t_state, TS_FLUSH);
1705	else
1706		ndflush(&tp->t_outq, (int)(zst->zst_tba - tp->t_outq.c_cf));
1707	(*linesw[tp->t_line].l_start)(tp);
1708}
1709
1710integrate void
1711zstty_stsoft(zst, tp)
1712	struct zstty_softc *zst;
1713	struct tty *tp;
1714{
1715	struct zs_chanstate *cs = zst->zst_cs;
1716	u_char rr0, delta;
1717	int s;
1718
1719	s = splzs();
1720	rr0 = cs->cs_rr0;
1721	delta = cs->cs_rr0_delta;
1722	cs->cs_rr0_delta = 0;
1723	splx(s);
1724
1725	if (ISSET(delta, cs->cs_rr0_dcd)) {
1726		/*
1727		 * Inform the tty layer that carrier detect changed.
1728		 */
1729		(void) (*linesw[tp->t_line].l_modem)(tp, ISSET(rr0, ZSRR0_DCD));
1730	}
1731
1732	if (ISSET(delta, cs->cs_rr0_cts)) {
1733		/* Block or unblock output according to flow control. */
1734		if (ISSET(rr0, cs->cs_rr0_cts)) {
1735			zst->zst_tx_stopped = 0;
1736			(*linesw[tp->t_line].l_start)(tp);
1737		} else {
1738			zst->zst_tx_stopped = 1;
1739		}
1740	}
1741}
1742
1743/*
1744 * Software interrupt.  Called at zssoft
1745 *
1746 * The main job to be done here is to empty the input ring
1747 * by passing its contents up to the tty layer.  The ring is
1748 * always emptied during this operation, therefore the ring
1749 * must not be larger than the space after "high water" in
1750 * the tty layer, or the tty layer might drop our input.
1751 *
1752 * Note: an "input blockage" condition is assumed to exist if
1753 * EITHER the TS_TBLOCK flag or zst_rx_blocked flag is set.
1754 */
1755static void
1756zstty_softint(cs)
1757	struct zs_chanstate *cs;
1758{
1759	struct zstty_softc *zst = cs->cs_private;
1760	struct tty *tp = zst->zst_tty;
1761	int s;
1762
1763	s = spltty();
1764
1765	if (zst->zst_rx_ready) {
1766		zst->zst_rx_ready = 0;
1767		zstty_rxsoft(zst, tp);
1768	}
1769
1770	if (zst->zst_st_check) {
1771		zst->zst_st_check = 0;
1772		zstty_stsoft(zst, tp);
1773	}
1774
1775	if (zst->zst_tx_done) {
1776		zst->zst_tx_done = 0;
1777		zstty_txsoft(zst, tp);
1778	}
1779
1780	splx(s);
1781}
1782
1783struct zsops zsops_tty = {
1784	zstty_rxint,	/* receive char available */
1785	zstty_stint,	/* external/status */
1786	zstty_txint,	/* xmit buffer empty */
1787	zstty_softint,	/* process software interrupt */
1788};
1789