zs.c revision 1.56
1/*	$NetBSD: zs.c,v 1.56 2008/04/29 06:53:01 martin Exp $	*/
2
3/*
4 * Copyright (c) 1992, 1993
5 *	The Regents of the University of California.  All rights reserved.
6 *
7 * This software was developed by the Computer Systems Engineering group
8 * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
9 * contributed to Berkeley.
10 *
11 *
12 * All advertising materials mentioning features or use of this software
13 * must display the following acknowledgement:
14 *	This product includes software developed by the University of
15 *	California, Lawrence Berkeley Laboratory.
16 *
17 * Redistribution and use in source and binary forms, with or without
18 * modification, are permitted provided that the following conditions
19 * are met:
20 * 1. Redistributions of source code must retain the above copyright
21 *    notice, this list of conditions and the following disclaimer.
22 * 2. Redistributions in binary form must reproduce the above copyright
23 *    notice, this list of conditions and the following disclaimer in the
24 *    documentation and/or other materials provided with the distribution.
25 * 3. Neither the name of the University nor the names of its contributors
26 *    may be used to endorse or promote products derived from this software
27 *    without specific prior written permission.
28 *
29 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
30 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
31 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
32 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
33 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
34 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
35 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
36 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
37 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
38 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
39 * SUCH DAMAGE.
40 *
41 *	@(#)zs.c	8.1 (Berkeley) 7/19/93
42 */
43
44/*-
45 * Copyright (c) 1995 The NetBSD Foundation, Inc. (Atari modifications)
46 * All rights reserved.
47 *
48 * This code is derived from software contributed to The NetBSD Foundation
49 * by Leo Weppelman.
50 *
51 * Redistribution and use in source and binary forms, with or without
52 * modification, are permitted provided that the following conditions
53 * are met:
54 * 1. Redistributions of source code must retain the above copyright
55 *    notice, this list of conditions and the following disclaimer.
56 * 2. Redistributions in binary form must reproduce the above copyright
57 *    notice, this list of conditions and the following disclaimer in the
58 *    documentation and/or other materials provided with the distribution.
59 *
60 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
61 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
62 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
63 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
64 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
65 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
66 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
67 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
68 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
69 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
70 * POSSIBILITY OF SUCH DAMAGE.
71 */
72
73/*
74 * Zilog Z8530 (ZSCC) driver.
75 *
76 * Runs two tty ports (modem2 and serial2) on zs0.
77 *
78 * This driver knows far too much about chip to usage mappings.
79 */
80
81#include <sys/cdefs.h>
82__KERNEL_RCSID(0, "$NetBSD: zs.c,v 1.56 2008/04/29 06:53:01 martin Exp $");
83
84#include <sys/param.h>
85#include <sys/systm.h>
86#include <sys/proc.h>
87#include <sys/device.h>
88#include <sys/conf.h>
89#include <sys/file.h>
90#include <sys/ioctl.h>
91#include <sys/malloc.h>
92#include <sys/tty.h>
93#include <sys/time.h>
94#include <sys/kernel.h>
95#include <sys/syslog.h>
96#include <sys/kauth.h>
97
98#include <machine/cpu.h>
99#include <machine/iomap.h>
100#include <machine/scu.h>
101#include <machine/mfp.h>
102#include <atari/dev/ym2149reg.h>
103
104#include <dev/ic/z8530reg.h>
105#include <atari/dev/zsvar.h>
106#include "zs.h"
107#if NZS > 1
108#error "This driver supports only 1 85C30!"
109#endif
110
111#if NZS > 0
112
113#define PCLK	(8053976)	/* PCLK pin input clock rate */
114#define PCLK_HD	(9600 * 1536)	/* PCLK on Hades pin input clock rate */
115
116#define splzs	spl5
117
118/*
119 * Software state per found chip.
120 */
121struct zs_softc {
122    struct	device		zi_dev;    /* base device		  */
123    volatile struct zsdevice	*zi_zs;    /* chip registers		  */
124    struct	zs_chanstate	zi_cs[2];  /* chan A and B software state */
125};
126
127static u_char	cb_scheduled = 0;	/* Already asked for callback? */
128/*
129 * Define the registers for a closed port
130 */
131static u_char zs_init_regs[16] = {
132/*  0 */	0,
133/*  1 */	0,
134/*  2 */	0x60,
135/*  3 */	0,
136/*  4 */	0,
137/*  5 */	0,
138/*  6 */	0,
139/*  7 */	0,
140/*  8 */	0,
141/*  9 */	ZSWR9_MASTER_IE | ZSWR9_VECTOR_INCL_STAT,
142/* 10 */	ZSWR10_NRZ,
143/* 11 */	ZSWR11_TXCLK_BAUD | ZSWR11_RXCLK_BAUD,
144/* 12 */	0,
145/* 13 */	0,
146/* 14 */	ZSWR14_BAUD_FROM_PCLK | ZSWR14_BAUD_ENA,
147/* 15 */	0
148};
149
150/*
151 * Define the machine dependant clock frequencies
152 * If BRgen feeds sender/receiver we always use a
153 * divisor 16, therefor the division by 16 can as
154 * well be done here.
155 */
156static u_long zs_freqs_tt[] = {
157	/*
158	 * Atari TT, RTxCB is generated by TT-MFP timer C,
159	 * which is set to 307.2 kHz during initialisation
160	 * and never changed afterwards.
161	 */
162	PCLK/16,	/* BRgen, PCLK,  divisor 16	*/
163	 229500,	/* BRgen, RTxCA, divisor 16	*/
164	3672000,	/* RTxCA, from PCLK4		*/
165	      0,	/* TRxCA, external		*/
166
167	PCLK/16,	/* BRgen, PCLK,  divisor 16	*/
168	  19200,	/* BRgen, RTxCB, divisor 16	*/
169	 307200,	/* RTxCB, from TT-MFP TCO	*/
170	2457600		/* TRxCB, from BCLK		*/
171};
172
173static u_long zs_freqs_falcon[] = {
174	/*
175	 * Atari Falcon, XXX no specs available, this might be wrong
176	 */
177	PCLK/16,	/* BRgen, PCLK,  divisor 16	*/
178	 229500,	/* BRgen, RTxCA, divisor 16	*/
179	3672000,	/* RTxCA, ???			*/
180	      0,	/* TRxCA, external		*/
181
182	PCLK/16,	/* BRgen, PCLK,  divisor 16	*/
183	 229500,	/* BRgen, RTxCB, divisor 16	*/
184	3672000,	/* RTxCB, ???			*/
185	2457600		/* TRxCB, ???			*/
186};
187
188static u_long zs_freqs_hades[] = {
189	/*
190	 * XXX: Channel-A unchecked!!!!!
191	 */
192     PCLK_HD/16,	/* BRgen, PCLK,  divisor 16	*/
193	 229500,	/* BRgen, RTxCA, divisor 16	*/
194	3672000,	/* RTxCA, from PCLK4		*/
195	      0,	/* TRxCA, external		*/
196
197     PCLK_HD/16,	/* BRgen, PCLK,  divisor 16	*/
198	 235550,	/* BRgen, RTxCB, divisor 16	*/
199	3768800,	/* RTxCB, 3.7688MHz		*/
200	3768800		/* TRxCB, 3.7688MHz		*/
201};
202
203static u_long zs_freqs_generic[] = {
204	/*
205	 * other machines, assume only PCLK is available
206	 */
207	PCLK/16,	/* BRgen, PCLK,  divisor 16	*/
208	      0,	/* BRgen, RTxCA, divisor 16	*/
209	      0,	/* RTxCA, unknown		*/
210	      0,	/* TRxCA, unknown		*/
211
212	PCLK/16,	/* BRgen, PCLK,  divisor 16	*/
213	      0,	/* BRgen, RTxCB, divisor 16	*/
214	      0,	/* RTxCB, unknown		*/
215	      0		/* TRxCB, unknown		*/
216};
217static u_long *zs_frequencies;
218
219/* Definition of the driver for autoconfig. */
220static int	zsmatch __P((struct device *, struct cfdata *, void *));
221static void	zsattach __P((struct device *, struct device *, void *));
222
223CFATTACH_DECL(zs, sizeof(struct zs_softc),
224    zsmatch, zsattach, NULL, NULL);
225
226extern struct cfdriver zs_cd;
227
228/* {b,c}devsw[] function prototypes */
229dev_type_open(zsopen);
230dev_type_close(zsclose);
231dev_type_read(zsread);
232dev_type_write(zswrite);
233dev_type_ioctl(zsioctl);
234dev_type_stop(zsstop);
235dev_type_tty(zstty);
236dev_type_poll(zspoll);
237
238const struct cdevsw zs_cdevsw = {
239	zsopen, zsclose, zsread, zswrite, zsioctl,
240	zsstop, zstty, zspoll, nommap, ttykqfilter, D_TTY
241};
242
243/* Interrupt handlers. */
244int		zshard __P((long));
245static int	zssoft __P((long));
246static int	zsrint __P((struct zs_chanstate *, volatile struct zschan *));
247static int	zsxint __P((struct zs_chanstate *, volatile struct zschan *));
248static int	zssint __P((struct zs_chanstate *, volatile struct zschan *));
249
250static struct zs_chanstate *zslist;
251
252/* Routines called from other code. */
253static void	zsstart __P((struct tty *));
254
255/* Routines purely local to this driver. */
256static void	zsoverrun __P((int, long *, const char *));
257static int	zsparam __P((struct tty *, struct termios *));
258static int	zsbaudrate __P((int, int, int *, int *, int *, int *));
259static int	zs_modem __P((struct zs_chanstate *, int, int));
260static void	zs_loadchannelregs __P((volatile struct zschan *, u_char *));
261static void	zs_shutdown __P((struct zs_chanstate *));
262
263static int zsshortcuts;	/* number of "shortcut" software interrupts */
264
265static int
266zsmatch(pdp, cfp, auxp)
267struct device	*pdp;
268struct cfdata	*cfp;
269void		*auxp;
270{
271	static int	zs_matched = 0;
272
273	if(strcmp("zs", auxp) || zs_matched)
274		return(0);
275	zs_matched = 1;
276	return(1);
277}
278
279/*
280 * Attach a found zs.
281 */
282static void
283zsattach(parent, dev, aux)
284struct device	*parent;
285struct device	*dev;
286void		*aux;
287{
288	register struct zs_softc		*zi;
289	register struct zs_chanstate		*cs;
290	register volatile struct zsdevice	*addr;
291		 char				tmp;
292
293	addr      = (struct zsdevice *)AD_SCC;
294	zi        = (struct zs_softc *)dev;
295	zi->zi_zs = addr;
296	cs        = zi->zi_cs;
297
298	/*
299	 * Get the command register into a known state.
300	 */
301	tmp = addr->zs_chan[ZS_CHAN_A].zc_csr;
302	tmp = addr->zs_chan[ZS_CHAN_A].zc_csr;
303	tmp = addr->zs_chan[ZS_CHAN_B].zc_csr;
304	tmp = addr->zs_chan[ZS_CHAN_B].zc_csr;
305
306	/*
307	 * Do a hardware reset.
308	 */
309	ZS_WRITE(&addr->zs_chan[ZS_CHAN_A], 9, ZSWR9_HARD_RESET);
310	delay(50000);	/*enough ? */
311	ZS_WRITE(&addr->zs_chan[ZS_CHAN_A], 9, 0);
312
313	/*
314	 * Initialize both channels
315	 */
316	zs_loadchannelregs(&addr->zs_chan[ZS_CHAN_A], zs_init_regs);
317	zs_loadchannelregs(&addr->zs_chan[ZS_CHAN_B], zs_init_regs);
318
319	if(machineid & ATARI_TT) {
320		/*
321		 * ininitialise TT-MFP timer C: 307200Hz
322		 * timer C and D share one control register:
323		 *	bits 0-2 control timer D
324		 *	bits 4-6 control timer C
325		 */
326		int cr = MFP2->mf_tcdcr & 7;
327		MFP2->mf_tcdcr = cr;		/* stop timer C  */
328		MFP2->mf_tcdr  = 1;		/* counter 1     */
329		cr |= T_Q004 << 4;		/* divisor 4     */
330		MFP2->mf_tcdcr = cr;		/* start timer C */
331		/*
332		 * enable scc related interrupts
333		 */
334		SCU->vme_mask |= SCU_SCC;
335
336		zs_frequencies = zs_freqs_tt;
337	} else if (machineid & ATARI_FALCON) {
338		zs_frequencies = zs_freqs_falcon;
339	} else if (machineid & ATARI_HADES) {
340		zs_frequencies = zs_freqs_hades;
341	} else {
342		zs_frequencies = zs_freqs_generic;
343	}
344
345	/* link into interrupt list with order (A,B) (B=A+1) */
346	cs[0].cs_next = &cs[1];
347	cs[1].cs_next = zslist;
348	zslist        = cs;
349
350	cs->cs_unit  = 0;
351	cs->cs_zc    = &addr->zs_chan[ZS_CHAN_A];
352	cs++;
353	cs->cs_unit  = 1;
354	cs->cs_zc    = &addr->zs_chan[ZS_CHAN_B];
355
356	printf(": serial2 on channel a and modem2 on channel b\n");
357}
358
359/*
360 * Open a zs serial port.
361 */
362int
363zsopen(dev, flags, mode, l)
364dev_t		dev;
365int		flags;
366int		mode;
367struct lwp	*l;
368{
369	register struct tty		*tp;
370	register struct zs_chanstate	*cs;
371		 struct zs_softc	*zi;
372		 int			unit = ZS_UNIT(dev);
373		 int			zs = unit >> 1;
374		 int			error, s;
375
376	if(zs >= zs_cd.cd_ndevs || (zi = zs_cd.cd_devs[zs]) == NULL)
377		return (ENXIO);
378	cs = &zi->zi_cs[unit & 1];
379
380	/*
381	 * When port A (ser02) is selected on the TT, make sure
382	 * the port is enabled.
383	 */
384	if((machineid & ATARI_TT) && !(unit & 1))
385		ym2149_ser2(1);
386
387	if (cs->cs_rbuf == NULL) {
388		cs->cs_rbuf = malloc(ZLRB_RING_SIZE * sizeof(int), M_DEVBUF,
389								   M_WAITOK);
390	}
391
392	tp = cs->cs_ttyp;
393	if(tp == NULL) {
394		cs->cs_ttyp = tp = ttymalloc();
395		tty_attach(tp);
396		tp->t_dev   = dev;
397		tp->t_oproc = zsstart;
398		tp->t_param = zsparam;
399	}
400
401	if (kauth_authorize_device_tty(l->l_cred, KAUTH_DEVICE_TTY_OPEN, tp))
402		return (EBUSY);
403
404	s  = spltty();
405
406	/*
407	 * Do the following iff this is a first open.
408	 */
409	if (!(tp->t_state & TS_ISOPEN) && tp->t_wopen == 0) {
410		if(tp->t_ispeed == 0) {
411			tp->t_iflag = TTYDEF_IFLAG;
412			tp->t_oflag = TTYDEF_OFLAG;
413			tp->t_cflag = TTYDEF_CFLAG;
414			tp->t_lflag = TTYDEF_LFLAG;
415			tp->t_ispeed = tp->t_ospeed = TTYDEF_SPEED;
416		}
417		ttychars(tp);
418		ttsetwater(tp);
419
420		(void)zsparam(tp, &tp->t_termios);
421
422		/*
423		 * Turn on DTR.  We must always do this, even if carrier is not
424		 * present, because otherwise we'd have to use TIOCSDTR
425		 * immediately after setting CLOCAL, which applications do not
426		 * expect.  We always assert DTR while the device is open
427		 * unless explicitly requested to deassert it.
428		 */
429		zs_modem(cs, ZSWR5_RTS|ZSWR5_DTR, DMSET);
430		/* May never get a status intr. if DCD already on. -gwr */
431		if((cs->cs_rr0 = cs->cs_zc->zc_csr) & ZSRR0_DCD)
432			tp->t_state |= TS_CARR_ON;
433		if(cs->cs_softcar)
434			tp->t_state |= TS_CARR_ON;
435	}
436
437	splx(s);
438
439	error = ttyopen(tp, ZS_DIALOUT(dev), (flags & O_NONBLOCK));
440	if (error)
441		goto bad;
442
443	error = tp->t_linesw->l_open(dev, tp);
444	if(error)
445		goto bad;
446	return (0);
447
448bad:
449	if (!(tp->t_state & TS_ISOPEN) && tp->t_wopen == 0) {
450		/*
451		 * We failed to open the device, and nobody else had it opened.
452		 * Clean up the state as appropriate.
453		 */
454		zs_shutdown(cs);
455	}
456	return(error);
457}
458
459/*
460 * Close a zs serial port.
461 */
462int
463zsclose(dev, flags, mode, l)
464dev_t		dev;
465int		flags;
466int		mode;
467struct lwp	*l;
468{
469	register struct zs_chanstate	*cs;
470	register struct tty		*tp;
471		 struct zs_softc	*zi;
472		 int			unit = ZS_UNIT(dev);
473
474	zi = zs_cd.cd_devs[unit >> 1];
475	cs = &zi->zi_cs[unit & 1];
476	tp = cs->cs_ttyp;
477
478	tp->t_linesw->l_close(tp, flags);
479	ttyclose(tp);
480
481	if (!(tp->t_state & TS_ISOPEN) && tp->t_wopen == 0) {
482		/*
483		 * Although we got a last close, the device may still be in
484		 * use; e.g. if this was the dialout node, and there are still
485		 * processes waiting for carrier on the non-dialout node.
486		 */
487		zs_shutdown(cs);
488	}
489	return (0);
490}
491
492/*
493 * Read/write zs serial port.
494 */
495int
496zsread(dev, uio, flags)
497dev_t		dev;
498struct uio	*uio;
499int		flags;
500{
501	register struct zs_chanstate	*cs;
502	register struct zs_softc	*zi;
503	register struct tty		*tp;
504		 int			unit;
505
506	unit = ZS_UNIT(dev);
507	zi   = zs_cd.cd_devs[unit >> 1];
508	cs   = &zi->zi_cs[unit & 1];
509	tp   = cs->cs_ttyp;
510
511	return(tp->t_linesw->l_read(tp, uio, flags));
512}
513
514int
515zswrite(dev, uio, flags)
516dev_t		dev;
517struct uio	*uio;
518int		flags;
519{
520	register struct zs_chanstate	*cs;
521	register struct zs_softc	*zi;
522	register struct tty		*tp;
523		 int			unit;
524
525	unit = ZS_UNIT(dev);
526	zi   = zs_cd.cd_devs[unit >> 1];
527	cs   = &zi->zi_cs[unit & 1];
528	tp   = cs->cs_ttyp;
529
530	return(tp->t_linesw->l_write(tp, uio, flags));
531}
532
533int
534zspoll(dev, events, l)
535dev_t		dev;
536int		events;
537struct lwp	*l;
538{
539	register struct zs_chanstate	*cs;
540	register struct zs_softc	*zi;
541	register struct tty		*tp;
542		 int			unit;
543
544	unit = ZS_UNIT(dev);
545	zi   = zs_cd.cd_devs[unit >> 1];
546	cs   = &zi->zi_cs[unit & 1];
547	tp   = cs->cs_ttyp;
548
549	return ((*tp->t_linesw->l_poll)(tp, events, l));
550}
551
552struct tty *
553zstty(dev)
554dev_t	dev;
555{
556	register struct zs_chanstate	*cs;
557	register struct zs_softc	*zi;
558		 int			unit;
559
560	unit = ZS_UNIT(dev);
561	zi   = zs_cd.cd_devs[unit >> 1];
562	cs   = &zi->zi_cs[unit & 1];
563	return(cs->cs_ttyp);
564}
565
566/*
567 * ZS hardware interrupt.  Scan all ZS channels.  NB: we know here that
568 * channels are kept in (A,B) pairs.
569 *
570 * Do just a little, then get out; set a software interrupt if more
571 * work is needed.
572 *
573 * We deliberately ignore the vectoring Zilog gives us, and match up
574 * only the number of `reset interrupt under service' operations, not
575 * the order.
576 */
577
578int
579zshard(sr)
580long sr;
581{
582	register struct zs_chanstate	*a;
583#define	b (a + 1)
584	register volatile struct zschan *zc;
585	register int			rr3, intflags = 0, v, i;
586
587	do {
588	    intflags &= ~4;
589	    for(a = zslist; a != NULL; a = b->cs_next) {
590		rr3 = ZS_READ(a->cs_zc, 3);
591		if(rr3 & (ZSRR3_IP_A_RX|ZSRR3_IP_A_TX|ZSRR3_IP_A_STAT)) {
592			intflags |= 4|2;
593			zc = a->cs_zc;
594			i  = a->cs_rbput;
595			if(rr3 & ZSRR3_IP_A_RX && (v = zsrint(a, zc)) != 0) {
596				a->cs_rbuf[i++ & ZLRB_RING_MASK] = v;
597				intflags |= 1;
598			}
599			if(rr3 & ZSRR3_IP_A_TX && (v = zsxint(a, zc)) != 0) {
600				a->cs_rbuf[i++ & ZLRB_RING_MASK] = v;
601				intflags |= 1;
602			}
603			if(rr3 & ZSRR3_IP_A_STAT && (v = zssint(a, zc)) != 0) {
604				a->cs_rbuf[i++ & ZLRB_RING_MASK] = v;
605				intflags |= 1;
606			}
607			a->cs_rbput = i;
608		}
609		if(rr3 & (ZSRR3_IP_B_RX|ZSRR3_IP_B_TX|ZSRR3_IP_B_STAT)) {
610			intflags |= 4|2;
611			zc = b->cs_zc;
612			i  = b->cs_rbput;
613			if(rr3 & ZSRR3_IP_B_RX && (v = zsrint(b, zc)) != 0) {
614				b->cs_rbuf[i++ & ZLRB_RING_MASK] = v;
615				intflags |= 1;
616			}
617			if(rr3 & ZSRR3_IP_B_TX && (v = zsxint(b, zc)) != 0) {
618				b->cs_rbuf[i++ & ZLRB_RING_MASK] = v;
619				intflags |= 1;
620			}
621			if(rr3 & ZSRR3_IP_B_STAT && (v = zssint(b, zc)) != 0) {
622				b->cs_rbuf[i++ & ZLRB_RING_MASK] = v;
623				intflags |= 1;
624			}
625			b->cs_rbput = i;
626		}
627	    }
628	} while(intflags & 4);
629#undef b
630
631	if(intflags & 1) {
632		if(BASEPRI(sr)) {
633			spl1();
634			zsshortcuts++;
635			return(zssoft(sr));
636		}
637		else if(!cb_scheduled) {
638			cb_scheduled++;
639			add_sicallback((si_farg)zssoft, 0, 0);
640		}
641	}
642	return(intflags & 2);
643}
644
645static int
646zsrint(cs, zc)
647register struct zs_chanstate	*cs;
648register volatile struct zschan	*zc;
649{
650	register int c;
651
652	/*
653	 * First read the status, because read of the received char
654	 * destroy the status of this char.
655	 */
656	c = ZS_READ(zc, 1);
657	c |= (zc->zc_data << 8);
658
659	/* clear receive error & interrupt condition */
660	zc->zc_csr = ZSWR0_RESET_ERRORS;
661	zc->zc_csr = ZSWR0_CLR_INTR;
662
663	return(ZRING_MAKE(ZRING_RINT, c));
664}
665
666static int
667zsxint(cs, zc)
668register struct zs_chanstate	*cs;
669register volatile struct zschan	*zc;
670{
671	register int i = cs->cs_tbc;
672
673	if(i == 0) {
674		zc->zc_csr = ZSWR0_RESET_TXINT;
675		zc->zc_csr = ZSWR0_CLR_INTR;
676		return(ZRING_MAKE(ZRING_XINT, 0));
677	}
678	cs->cs_tbc = i - 1;
679	zc->zc_data = *cs->cs_tba++;
680	zc->zc_csr = ZSWR0_CLR_INTR;
681	return (0);
682}
683
684static int
685zssint(cs, zc)
686register struct zs_chanstate	*cs;
687register volatile struct zschan	*zc;
688{
689	register int rr0;
690
691	rr0 = zc->zc_csr;
692	zc->zc_csr = ZSWR0_RESET_STATUS;
693	zc->zc_csr = ZSWR0_CLR_INTR;
694	/*
695	 * The chip's hardware flow control is, as noted in zsreg.h,
696	 * busted---if the DCD line goes low the chip shuts off the
697	 * receiver (!).  If we want hardware CTS flow control but do
698	 * not have it, and carrier is now on, turn HFC on; if we have
699	 * HFC now but carrier has gone low, turn it off.
700	 */
701	if(rr0 & ZSRR0_DCD) {
702		if(cs->cs_ttyp->t_cflag & CCTS_OFLOW &&
703		    (cs->cs_creg[3] & ZSWR3_HFC) == 0) {
704			cs->cs_creg[3] |= ZSWR3_HFC;
705			ZS_WRITE(zc, 3, cs->cs_creg[3]);
706		}
707	}
708	else {
709		if (cs->cs_creg[3] & ZSWR3_HFC) {
710			cs->cs_creg[3] &= ~ZSWR3_HFC;
711			ZS_WRITE(zc, 3, cs->cs_creg[3]);
712		}
713	}
714	return(ZRING_MAKE(ZRING_SINT, rr0));
715}
716
717/*
718 * Print out a ring or fifo overrun error message.
719 */
720static void
721zsoverrun(unit, ptime, what)
722int	unit;
723long	*ptime;
724const char *what;
725{
726	time_t cur_sec = time_second;
727
728	if(*ptime != cur_sec) {
729		*ptime = cur_sec;
730		log(LOG_WARNING, "zs%d%c: %s overrun\n", unit >> 1,
731		    (unit & 1) + 'a', what);
732	}
733}
734
735/*
736 * ZS software interrupt.  Scan all channels for deferred interrupts.
737 */
738int
739zssoft(sr)
740long sr;
741{
742    register struct zs_chanstate	*cs;
743    register volatile struct zschan	*zc;
744    register struct linesw		*line;
745    register struct tty			*tp;
746    register int			get, n, c, cc, unit, s;
747 	     int			retval = 0;
748
749    cb_scheduled = 0;
750    s = spltty();
751    for(cs = zslist; cs != NULL; cs = cs->cs_next) {
752	get = cs->cs_rbget;
753again:
754	n = cs->cs_rbput;	/* atomic			*/
755	if(get == n)		/* nothing more on this line	*/
756		continue;
757	retval = 1;
758	unit   = cs->cs_unit;	/* set up to handle interrupts	*/
759	zc     = cs->cs_zc;
760	tp     = cs->cs_ttyp;
761	line   = tp->t_linesw;
762	/*
763	 * Compute the number of interrupts in the receive ring.
764	 * If the count is overlarge, we lost some events, and
765	 * must advance to the first valid one.  It may get
766	 * overwritten if more data are arriving, but this is
767	 * too expensive to check and gains nothing (we already
768	 * lost out; all we can do at this point is trade one
769	 * kind of loss for another).
770	 */
771	n -= get;
772	if(n > ZLRB_RING_SIZE) {
773		zsoverrun(unit, &cs->cs_rotime, "ring");
774		get += n - ZLRB_RING_SIZE;
775		n    = ZLRB_RING_SIZE;
776	}
777	while(--n >= 0) {
778		/* race to keep ahead of incoming interrupts */
779		c = cs->cs_rbuf[get++ & ZLRB_RING_MASK];
780		switch (ZRING_TYPE(c)) {
781
782		case ZRING_RINT:
783			c = ZRING_VALUE(c);
784			if(c & ZSRR1_DO)
785				zsoverrun(unit, &cs->cs_fotime, "fifo");
786			cc = c >> 8;
787			if(c & ZSRR1_FE)
788				cc |= TTY_FE;
789			if(c & ZSRR1_PE)
790				cc |= TTY_PE;
791			line->l_rint(cc, tp);
792			break;
793
794		case ZRING_XINT:
795			/*
796			 * Transmit done: change registers and resume,
797			 * or clear BUSY.
798			 */
799			if(cs->cs_heldchange) {
800				int sps;
801
802				sps = splzs();
803				c = zc->zc_csr;
804				if((c & ZSRR0_DCD) == 0)
805					cs->cs_preg[3] &= ~ZSWR3_HFC;
806				bcopy((void *)cs->cs_preg,
807				    (void *)cs->cs_creg, 16);
808				zs_loadchannelregs(zc, cs->cs_creg);
809				splx(sps);
810				cs->cs_heldchange = 0;
811				if(cs->cs_heldtbc
812					&& (tp->t_state & TS_TTSTOP) == 0) {
813					cs->cs_tbc = cs->cs_heldtbc - 1;
814					zc->zc_data = *cs->cs_tba++;
815					goto again;
816				}
817			}
818			tp->t_state &= ~TS_BUSY;
819			if(tp->t_state & TS_FLUSH)
820				tp->t_state &= ~TS_FLUSH;
821			else ndflush(&tp->t_outq,cs->cs_tba
822						- tp->t_outq.c_cf);
823			line->l_start(tp);
824			break;
825
826		case ZRING_SINT:
827			/*
828			 * Status line change.  HFC bit is run in
829			 * hardware interrupt, to avoid locking
830			 * at splzs here.
831			 */
832			c = ZRING_VALUE(c);
833			if((c ^ cs->cs_rr0) & ZSRR0_DCD) {
834				cc = (c & ZSRR0_DCD) != 0;
835				if(line->l_modem(tp, cc) == 0)
836					zs_modem(cs, ZSWR5_RTS|ZSWR5_DTR,
837							cc ? DMBIS : DMBIC);
838			}
839			cs->cs_rr0 = c;
840			break;
841
842		default:
843			log(LOG_ERR, "zs%d%c: bad ZRING_TYPE (%x)\n",
844			    unit >> 1, (unit & 1) + 'a', c);
845			break;
846		}
847	}
848	cs->cs_rbget = get;
849	goto again;
850    }
851    splx(s);
852    return (retval);
853}
854
855int
856zsioctl(dev, cmd, data, flag, l)
857dev_t		dev;
858u_long		cmd;
859void *		data;
860int		flag;
861struct lwp	*l;
862{
863		 int			unit = ZS_UNIT(dev);
864		 struct zs_softc	*zi = zs_cd.cd_devs[unit >> 1];
865	register struct tty		*tp = zi->zi_cs[unit & 1].cs_ttyp;
866	register int			error, s;
867	register struct zs_chanstate	*cs = &zi->zi_cs[unit & 1];
868
869	error = tp->t_linesw->l_ioctl(tp, cmd, data, flag, l);
870	if(error != EPASSTHROUGH)
871		return(error);
872
873	error = ttioctl(tp, cmd, data, flag, l);
874	if(error !=EPASSTHROUGH)
875		return (error);
876
877	switch (cmd) {
878	case TIOCSBRK:
879		s = splzs();
880		cs->cs_preg[5] |= ZSWR5_BREAK;
881		cs->cs_creg[5] |= ZSWR5_BREAK;
882		ZS_WRITE(cs->cs_zc, 5, cs->cs_creg[5]);
883		splx(s);
884		break;
885	case TIOCCBRK:
886		s = splzs();
887		cs->cs_preg[5] &= ~ZSWR5_BREAK;
888		cs->cs_creg[5] &= ~ZSWR5_BREAK;
889		ZS_WRITE(cs->cs_zc, 5, cs->cs_creg[5]);
890		splx(s);
891		break;
892	case TIOCGFLAGS: {
893		int bits = 0;
894
895		if(cs->cs_softcar)
896			bits |= TIOCFLAG_SOFTCAR;
897		if(cs->cs_creg[15] & ZSWR15_DCD_IE)
898			bits |= TIOCFLAG_CLOCAL;
899		if(cs->cs_creg[3] & ZSWR3_HFC)
900			bits |= TIOCFLAG_CRTSCTS;
901		*(int *)data = bits;
902		break;
903	}
904	case TIOCSFLAGS: {
905		int userbits = 0;
906
907		error = kauth_authorize_device_tty(l->l_cred,
908		    KAUTH_DEVICE_TTY_PRIVSET, tp);
909		if(error != 0)
910			return (EPERM);
911
912		userbits = *(int *)data;
913
914		/*
915		 * can have `local' or `softcar', and `rtscts' or `mdmbuf'
916		 # defaulting to software flow control.
917		 */
918		if(userbits & TIOCFLAG_SOFTCAR && userbits & TIOCFLAG_CLOCAL)
919			return(EINVAL);
920		if(userbits & TIOCFLAG_MDMBUF)	/* don't support this (yet?) */
921			return(ENODEV);
922
923		s = splzs();
924		if((userbits & TIOCFLAG_SOFTCAR)) {
925			cs->cs_softcar = 1;	/* turn on softcar */
926			cs->cs_preg[15] &= ~ZSWR15_DCD_IE; /* turn off dcd */
927			cs->cs_creg[15] &= ~ZSWR15_DCD_IE;
928			ZS_WRITE(cs->cs_zc, 15, cs->cs_creg[15]);
929		}
930		else if(userbits & TIOCFLAG_CLOCAL) {
931			cs->cs_softcar = 0; 	/* turn off softcar */
932			cs->cs_preg[15] |= ZSWR15_DCD_IE; /* turn on dcd */
933			cs->cs_creg[15] |= ZSWR15_DCD_IE;
934			ZS_WRITE(cs->cs_zc, 15, cs->cs_creg[15]);
935			tp->t_termios.c_cflag |= CLOCAL;
936		}
937		if(userbits & TIOCFLAG_CRTSCTS) {
938			cs->cs_preg[15] |= ZSWR15_CTS_IE;
939			cs->cs_creg[15] |= ZSWR15_CTS_IE;
940			ZS_WRITE(cs->cs_zc, 15, cs->cs_creg[15]);
941			cs->cs_preg[3] |= ZSWR3_HFC;
942			cs->cs_creg[3] |= ZSWR3_HFC;
943			ZS_WRITE(cs->cs_zc, 3, cs->cs_creg[3]);
944			tp->t_termios.c_cflag |= CRTSCTS;
945		}
946		else {
947			/* no mdmbuf, so we must want software flow control */
948			cs->cs_preg[15] &= ~ZSWR15_CTS_IE;
949			cs->cs_creg[15] &= ~ZSWR15_CTS_IE;
950			ZS_WRITE(cs->cs_zc, 15, cs->cs_creg[15]);
951			cs->cs_preg[3] &= ~ZSWR3_HFC;
952			cs->cs_creg[3] &= ~ZSWR3_HFC;
953			ZS_WRITE(cs->cs_zc, 3, cs->cs_creg[3]);
954			tp->t_termios.c_cflag &= ~CRTSCTS;
955		}
956		splx(s);
957		break;
958	}
959	case TIOCSDTR:
960		zs_modem(cs, ZSWR5_DTR, DMBIS);
961		break;
962	case TIOCCDTR:
963		zs_modem(cs, ZSWR5_DTR, DMBIC);
964		break;
965	case TIOCMGET:
966		zs_modem(cs, 0, DMGET);
967		break;
968	case TIOCMSET:
969	case TIOCMBIS:
970	case TIOCMBIC:
971	default:
972		return (EPASSTHROUGH);
973	}
974	return (0);
975}
976
977/*
978 * Start or restart transmission.
979 */
980static void
981zsstart(tp)
982register struct tty *tp;
983{
984	register struct zs_chanstate	*cs;
985	register int			s, nch;
986		 int			unit = ZS_UNIT(tp->t_dev);
987		 struct zs_softc	*zi = zs_cd.cd_devs[unit >> 1];
988
989	cs = &zi->zi_cs[unit & 1];
990	s  = spltty();
991
992	/*
993	 * If currently active or delaying, no need to do anything.
994	 */
995	if(tp->t_state & (TS_TIMEOUT | TS_BUSY | TS_TTSTOP))
996		goto out;
997
998	/*
999	 * If there are sleepers, and output has drained below low
1000	 * water mark, awaken.
1001	 */
1002	ttypull(tp);
1003
1004	nch = ndqb(&tp->t_outq, 0);	/* XXX */
1005	if(nch) {
1006		register char *p = tp->t_outq.c_cf;
1007
1008		/* mark busy, enable tx done interrupts, & send first byte */
1009		tp->t_state |= TS_BUSY;
1010		(void) splzs();
1011		cs->cs_preg[1] |= ZSWR1_TIE;
1012		cs->cs_creg[1] |= ZSWR1_TIE;
1013		ZS_WRITE(cs->cs_zc, 1, cs->cs_creg[1]);
1014		cs->cs_zc->zc_data = *p;
1015		cs->cs_tba = p + 1;
1016		cs->cs_tbc = nch - 1;
1017	} else {
1018		/*
1019		 * Nothing to send, turn off transmit done interrupts.
1020		 * This is useful if something is doing polled output.
1021		 */
1022		(void) splzs();
1023		cs->cs_preg[1] &= ~ZSWR1_TIE;
1024		cs->cs_creg[1] &= ~ZSWR1_TIE;
1025		ZS_WRITE(cs->cs_zc, 1, cs->cs_creg[1]);
1026	}
1027out:
1028	splx(s);
1029}
1030
1031/*
1032 * Stop output, e.g., for ^S or output flush.
1033 */
1034void
1035zsstop(tp, flag)
1036register struct tty	*tp;
1037	 int		flag;
1038{
1039	register struct zs_chanstate	*cs;
1040	register int			s, unit = ZS_UNIT(tp->t_dev);
1041		 struct zs_softc	*zi = zs_cd.cd_devs[unit >> 1];
1042
1043	cs = &zi->zi_cs[unit & 1];
1044	s  = splzs();
1045	if(tp->t_state & TS_BUSY) {
1046		/*
1047		 * Device is transmitting; must stop it.
1048		 */
1049		cs->cs_tbc = 0;
1050		if ((tp->t_state & TS_TTSTOP) == 0)
1051			tp->t_state |= TS_FLUSH;
1052	}
1053	splx(s);
1054}
1055
1056static void
1057zs_shutdown(cs)
1058	struct zs_chanstate	*cs;
1059{
1060	struct tty	*tp = cs->cs_ttyp;
1061	int		s;
1062
1063	s = splzs();
1064
1065	/*
1066	 * Hang up if necessary.  Wait a bit, so the other side has time to
1067	 * notice even if we immediately open the port again.
1068	 */
1069	if(tp->t_cflag & HUPCL) {
1070		zs_modem(cs, 0, DMSET);
1071		(void)tsleep((void *)cs, TTIPRI, ttclos, hz);
1072	}
1073
1074	/* Clear any break condition set with TIOCSBRK. */
1075	if(cs->cs_creg[5] & ZSWR5_BREAK) {
1076		cs->cs_preg[5] &= ~ZSWR5_BREAK;
1077		cs->cs_creg[5] &= ~ZSWR5_BREAK;
1078		ZS_WRITE(cs->cs_zc, 5, cs->cs_creg[5]);
1079	}
1080
1081	/*
1082	 * Drop all lines and cancel interrupts
1083	 */
1084	zs_loadchannelregs(cs->cs_zc, zs_init_regs);
1085	splx(s);
1086}
1087
1088/*
1089 * Set ZS tty parameters from termios.
1090 *
1091 * This routine makes use of the fact that only registers
1092 * 1, 3, 4, 5, 9, 10, 11, 12, 13, 14, and 15 are written.
1093 */
1094static int
1095zsparam(tp, t)
1096register struct tty	*tp;
1097register struct termios	*t;
1098{
1099		 int			unit = ZS_UNIT(tp->t_dev);
1100		 struct zs_softc	*zi = zs_cd.cd_devs[unit >> 1];
1101	register struct zs_chanstate	*cs = &zi->zi_cs[unit & 1];
1102		 int			cdiv = 0,	/* XXX gcc4 -Wuninitialized */
1103					clkm = 0,	/* XXX gcc4 -Wuninitialized */
1104					brgm = 0,	/* XXX gcc4 -Wuninitialized */
1105					tcon = 0;	/* XXX gcc4 -Wuninitialized */
1106	register int			tmp, tmp5, cflag, s;
1107
1108	tmp  = t->c_ospeed;
1109	tmp5 = t->c_ispeed;
1110	if(tmp < 0 || (tmp5 && tmp5 != tmp))
1111		return(EINVAL);
1112	if(tmp == 0) {
1113		/* stty 0 => drop DTR and RTS */
1114		zs_modem(cs, 0, DMSET);
1115		return(0);
1116	}
1117	tmp = zsbaudrate(unit, tmp, &cdiv, &clkm, &brgm, &tcon);
1118	if (tmp < 0)
1119		return(EINVAL);
1120	tp->t_ispeed = tp->t_ospeed = tmp;
1121
1122	cflag = tp->t_cflag = t->c_cflag;
1123	if (cflag & CSTOPB)
1124		cdiv |= ZSWR4_TWOSB;
1125	else
1126		cdiv |= ZSWR4_ONESB;
1127	if (!(cflag & PARODD))
1128		cdiv |= ZSWR4_EVENP;
1129	if (cflag & PARENB)
1130		cdiv |= ZSWR4_PARENB;
1131
1132	switch(cflag & CSIZE) {
1133	case CS5:
1134		tmp  = ZSWR3_RX_5;
1135		tmp5 = ZSWR5_TX_5;
1136		break;
1137	case CS6:
1138		tmp  = ZSWR3_RX_6;
1139		tmp5 = ZSWR5_TX_6;
1140		break;
1141	case CS7:
1142		tmp  = ZSWR3_RX_7;
1143		tmp5 = ZSWR5_TX_7;
1144		break;
1145	case CS8:
1146	default:
1147		tmp  = ZSWR3_RX_8;
1148		tmp5 = ZSWR5_TX_8;
1149		break;
1150	}
1151	tmp  |= ZSWR3_RX_ENABLE;
1152	tmp5 |= ZSWR5_TX_ENABLE | ZSWR5_DTR | ZSWR5_RTS;
1153
1154	/*
1155	 * Block interrupts so that state will not
1156	 * be altered until we are done setting it up.
1157	 */
1158	s = splzs();
1159	cs->cs_preg[4]  = cdiv;
1160	cs->cs_preg[11] = clkm;
1161	cs->cs_preg[12] = tcon;
1162	cs->cs_preg[13] = tcon >> 8;
1163	cs->cs_preg[14] = brgm;
1164	cs->cs_preg[1]  = ZSWR1_RIE | ZSWR1_TIE | ZSWR1_SIE;
1165	cs->cs_preg[9]  = ZSWR9_MASTER_IE | ZSWR9_VECTOR_INCL_STAT;
1166	cs->cs_preg[10] = ZSWR10_NRZ;
1167	cs->cs_preg[15] = ZSWR15_BREAK_IE | ZSWR15_DCD_IE;
1168
1169	/*
1170	 * Output hardware flow control on the chip is horrendous: if
1171	 * carrier detect drops, the receiver is disabled.  Hence we
1172	 * can only do this when the carrier is on.
1173	 */
1174	if(cflag & CCTS_OFLOW && cs->cs_zc->zc_csr & ZSRR0_DCD)
1175		tmp |= ZSWR3_HFC;
1176	cs->cs_preg[3] = tmp;
1177	cs->cs_preg[5] = tmp5;
1178
1179	/*
1180	 * If nothing is being transmitted, set up new current values,
1181	 * else mark them as pending.
1182	 */
1183	if(cs->cs_heldchange == 0) {
1184		if (cs->cs_ttyp->t_state & TS_BUSY) {
1185			cs->cs_heldtbc = cs->cs_tbc;
1186			cs->cs_tbc = 0;
1187			cs->cs_heldchange = 1;
1188		} else {
1189			bcopy((void *)cs->cs_preg, (void *)cs->cs_creg, 16);
1190			zs_loadchannelregs(cs->cs_zc, cs->cs_creg);
1191		}
1192	}
1193	splx(s);
1194	return (0);
1195}
1196
1197/*
1198 * search for the best matching baudrate
1199 */
1200static int
1201zsbaudrate(unit, wanted, divisor, clockmode, brgenmode, timeconst)
1202int	unit, wanted, *divisor, *clockmode, *brgenmode, *timeconst;
1203{
1204	int	bestdiff, bestbps, source;
1205
1206	bestdiff = bestbps = 0;
1207	unit = (unit & 1) << 2;
1208	for (source = 0; source < 4; ++source) {
1209		long	freq = zs_frequencies[unit + source];
1210		int	diff, bps, div, clkm, brgm, tcon;
1211
1212		bps = div = clkm = brgm = tcon = 0;
1213		switch (source) {
1214			case 0:	/* BRgen, PCLK */
1215				brgm = ZSWR14_BAUD_ENA|ZSWR14_BAUD_FROM_PCLK;
1216				break;
1217			case 1:	/* BRgen, RTxC */
1218				brgm = ZSWR14_BAUD_ENA;
1219				break;
1220			case 2: /* RTxC */
1221				clkm = ZSWR11_RXCLK_RTXC|ZSWR11_TXCLK_RTXC;
1222				break;
1223			case 3: /* TRxC */
1224				clkm = ZSWR11_RXCLK_TRXC|ZSWR11_TXCLK_TRXC;
1225				break;
1226		}
1227		switch (source) {
1228			case 0:
1229			case 1:
1230				div  = ZSWR4_CLK_X16;
1231				clkm = ZSWR11_RXCLK_BAUD|ZSWR11_TXCLK_BAUD;
1232				tcon = BPS_TO_TCONST(freq, wanted);
1233				if (tcon < 0)
1234					tcon = 0;
1235				bps  = TCONST_TO_BPS(freq, tcon);
1236				break;
1237			case 2:
1238			case 3:
1239			{	int	b1 = freq / 16, d1 = abs(b1 - wanted);
1240				int	b2 = freq / 32, d2 = abs(b2 - wanted);
1241				int	b3 = freq / 64, d3 = abs(b3 - wanted);
1242
1243				if (d1 < d2 && d1 < d3) {
1244					div = ZSWR4_CLK_X16;
1245					bps = b1;
1246				} else if (d2 < d3 && d2 < d1) {
1247					div = ZSWR4_CLK_X32;
1248					bps = b2;
1249				} else {
1250					div = ZSWR4_CLK_X64;
1251					bps = b3;
1252				}
1253				brgm = tcon = 0;
1254				break;
1255			}
1256		}
1257		diff = abs(bps - wanted);
1258		if (!source || diff < bestdiff) {
1259			*divisor   = div;
1260			*clockmode = clkm;
1261			*brgenmode = brgm;
1262			*timeconst = tcon;
1263			bestbps    = bps;
1264			bestdiff   = diff;
1265			if (diff == 0)
1266				break;
1267		}
1268	}
1269	/* Allow deviations upto 5% */
1270	if (20 * bestdiff > wanted)
1271		return -1;
1272	return bestbps;
1273}
1274
1275/*
1276 * Raise or lower modem control (DTR/RTS) signals.  If a character is
1277 * in transmission, the change is deferred.
1278 */
1279static int
1280zs_modem(cs, bits, how)
1281struct zs_chanstate	*cs;
1282int			bits, how;
1283{
1284	int s, mbits;
1285
1286	bits  &= ZSWR5_DTR | ZSWR5_RTS;
1287
1288	s = splzs();
1289	mbits  = cs->cs_preg[5] &  (ZSWR5_DTR | ZSWR5_RTS);
1290
1291	switch(how) {
1292		case DMSET:
1293				mbits  = bits;
1294				break;
1295		case DMBIS:
1296				mbits |= bits;
1297				break;
1298		case DMBIC:
1299				mbits &= ~bits;
1300				break;
1301		case DMGET:
1302				splx(s);
1303				return(mbits);
1304	}
1305
1306	cs->cs_preg[5] = (cs->cs_preg[5] & ~(ZSWR5_DTR | ZSWR5_RTS)) | mbits;
1307	if(cs->cs_heldchange == 0) {
1308		if(cs->cs_ttyp->t_state & TS_BUSY) {
1309			cs->cs_heldtbc = cs->cs_tbc;
1310			cs->cs_tbc = 0;
1311			cs->cs_heldchange = 1;
1312		}
1313		else {
1314			ZS_WRITE(cs->cs_zc, 5, cs->cs_creg[5]);
1315		}
1316	}
1317	splx(s);
1318	return(0);
1319}
1320
1321/*
1322 * Write the given register set to the given zs channel in the proper order.
1323 * The channel must not be transmitting at the time.  The receiver will
1324 * be disabled for the time it takes to write all the registers.
1325 */
1326static void
1327zs_loadchannelregs(zc, reg)
1328volatile struct zschan	*zc;
1329u_char			*reg;
1330{
1331	int i;
1332
1333	zc->zc_csr = ZSM_RESET_ERR;	/* reset error condition */
1334	i = zc->zc_data;		/* drain fifo */
1335	i = zc->zc_data;
1336	i = zc->zc_data;
1337	ZS_WRITE(zc,  4, reg[4]);
1338	ZS_WRITE(zc, 10, reg[10]);
1339	ZS_WRITE(zc,  3, reg[3] & ~ZSWR3_RX_ENABLE);
1340	ZS_WRITE(zc,  5, reg[5] & ~ZSWR5_TX_ENABLE);
1341	ZS_WRITE(zc,  1, reg[1]);
1342	ZS_WRITE(zc,  9, reg[9]);
1343	ZS_WRITE(zc, 11, reg[11]);
1344	ZS_WRITE(zc, 12, reg[12]);
1345	ZS_WRITE(zc, 13, reg[13]);
1346	ZS_WRITE(zc, 14, reg[14]);
1347	ZS_WRITE(zc, 15, reg[15]);
1348	ZS_WRITE(zc,  3, reg[3]);
1349	ZS_WRITE(zc,  5, reg[5]);
1350}
1351#endif /* NZS > 1 */
1352