xref: /netbsd-src/sys/dev/ic/z8530tty.c (revision b1c86f5f087524e68db12794ee9c3e3da1ab17a0)
1 /*	$NetBSD: z8530tty.c,v 1.127 2009/05/22 03:51:30 mrg 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) 1992, 1993
35  *	The Regents of the University of California.  All rights reserved.
36  *
37  * This software was developed by the Computer Systems Engineering group
38  * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
39  * contributed to Berkeley.
40  *
41  * All advertising materials mentioning features or use of this software
42  * must display the following acknowledgement:
43  *	This product includes software developed by the University of
44  *	California, Lawrence Berkeley Laboratory.
45  *
46  * Redistribution and use in source and binary forms, with or without
47  * modification, are permitted provided that the following conditions
48  * are met:
49  * 1. Redistributions of source code must retain the above copyright
50  *    notice, this list of conditions and the following disclaimer.
51  * 2. Redistributions in binary form must reproduce the above copyright
52  *    notice, this list of conditions and the following disclaimer in the
53  *    documentation and/or other materials provided with the distribution.
54  * 3. Neither the name of the University nor the names of its contributors
55  *    may be used to endorse or promote products derived from this software
56  *    without specific prior written permission.
57  *
58  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
59  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
60  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
61  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
62  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
63  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
64  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
65  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
66  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
67  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
68  * SUCH DAMAGE.
69  *
70  *	@(#)zs.c	8.1 (Berkeley) 7/19/93
71  */
72 
73 /*
74  * Copyright (c) 1994 Gordon W. Ross
75  *
76  * This software was developed by the Computer Systems Engineering group
77  * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
78  * contributed to Berkeley.
79  *
80  * All advertising materials mentioning features or use of this software
81  * must display the following acknowledgement:
82  *	This product includes software developed by the University of
83  *	California, Lawrence Berkeley Laboratory.
84  *
85  * Redistribution and use in source and binary forms, with or without
86  * modification, are permitted provided that the following conditions
87  * are met:
88  * 1. Redistributions of source code must retain the above copyright
89  *    notice, this list of conditions and the following disclaimer.
90  * 2. Redistributions in binary form must reproduce the above copyright
91  *    notice, this list of conditions and the following disclaimer in the
92  *    documentation and/or other materials provided with the distribution.
93  * 3. All advertising materials mentioning features or use of this software
94  *    must display the following acknowledgement:
95  *	This product includes software developed by the University of
96  *	California, Berkeley and its contributors.
97  * 4. Neither the name of the University nor the names of its contributors
98  *    may be used to endorse or promote products derived from this software
99  *    without specific prior written permission.
100  *
101  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
102  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
103  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
104  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
105  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
106  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
107  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
108  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
109  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
110  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
111  * SUCH DAMAGE.
112  *
113  *	@(#)zs.c	8.1 (Berkeley) 7/19/93
114  */
115 
116 /*
117  * Zilog Z8530 Dual UART driver (tty interface)
118  *
119  * This is the "slave" driver that will be attached to
120  * the "zsc" driver for plain "tty" async. serial lines.
121  *
122  * Credits, history:
123  *
124  * The original version of this code was the sparc/dev/zs.c driver
125  * as distributed with the Berkeley 4.4 Lite release.  Since then,
126  * Gordon Ross reorganized the code into the current parent/child
127  * driver scheme, separating the Sun keyboard and mouse support
128  * into independent child drivers.
129  *
130  * RTS/CTS flow-control support was a collaboration of:
131  *	Gordon Ross <gwr@NetBSD.org>,
132  *	Bill Studenmund <wrstuden@loki.stanford.edu>
133  *	Ian Dall <Ian.Dall@dsto.defence.gov.au>
134  *
135  * The driver was massively overhauled in November 1997 by Charles Hannum,
136  * fixing *many* bugs, and substantially improving performance.
137  */
138 
139 #include <sys/cdefs.h>
140 __KERNEL_RCSID(0, "$NetBSD: z8530tty.c,v 1.127 2009/05/22 03:51:30 mrg Exp $");
141 
142 #include "opt_kgdb.h"
143 #include "opt_ntp.h"
144 
145 #include <sys/param.h>
146 #include <sys/systm.h>
147 #include <sys/proc.h>
148 #include <sys/device.h>
149 #include <sys/conf.h>
150 #include <sys/file.h>
151 #include <sys/ioctl.h>
152 #include <sys/malloc.h>
153 #include <sys/timepps.h>
154 #include <sys/tty.h>
155 #include <sys/time.h>
156 #include <sys/kernel.h>
157 #include <sys/syslog.h>
158 #include <sys/kauth.h>
159 
160 #include <dev/ic/z8530reg.h>
161 #include <machine/z8530var.h>
162 
163 #include <dev/cons.h>
164 
165 #include "ioconf.h"
166 #include "locators.h"
167 
168 /*
169  * How many input characters we can buffer.
170  * The port-specific var.h may override this.
171  * Note: must be a power of two!
172  */
173 #ifndef	ZSTTY_RING_SIZE
174 #define	ZSTTY_RING_SIZE	2048
175 #endif
176 
177 static struct cnm_state zstty_cnm_state;
178 /*
179  * Make this an option variable one can patch.
180  * But be warned:  this must be a power of 2!
181  */
182 u_int zstty_rbuf_size = ZSTTY_RING_SIZE;
183 
184 /* Stop input when 3/4 of the ring is full; restart when only 1/4 is full. */
185 u_int zstty_rbuf_hiwat = (ZSTTY_RING_SIZE * 1) / 4;
186 u_int zstty_rbuf_lowat = (ZSTTY_RING_SIZE * 3) / 4;
187 
188 struct zstty_softc {
189 	device_t zst_dev;		/* required first: base device */
190 	struct  tty *zst_tty;
191 	struct	zs_chanstate *zst_cs;
192 
193 	struct callout zst_diag_ch;
194 
195 	u_int zst_overflows,
196 	      zst_floods,
197 	      zst_errors;
198 
199 	int zst_hwflags,	/* see z8530var.h */
200 	    zst_swflags;	/* TIOCFLAG_SOFTCAR, ... <ttycom.h> */
201 
202 	u_int zst_r_hiwat,
203 	      zst_r_lowat;
204 	uint8_t *volatile zst_rbget,
205 	        *volatile zst_rbput;
206 	volatile u_int zst_rbavail;
207 	uint8_t *zst_rbuf,
208 	        *zst_ebuf;
209 
210 	/*
211 	 * The transmit byte count and address are used for pseudo-DMA
212 	 * output in the hardware interrupt code.  PDMA can be suspended
213 	 * to get pending changes done; heldtbc is used for this.  It can
214 	 * also be stopped for ^S; this sets TS_TTSTOP in tp->t_state.
215 	 */
216 	uint8_t *zst_tba;		/* transmit buffer address */
217 	u_int zst_tbc,			/* transmit byte count */
218 	      zst_heldtbc;		/* held tbc while xmission stopped */
219 
220 	/* Flags to communicate with zstty_softint() */
221 	volatile uint8_t zst_rx_flags,	/* receiver blocked */
222 #define	RX_TTY_BLOCKED		0x01
223 #define	RX_TTY_OVERFLOWED	0x02
224 #define	RX_IBUF_BLOCKED		0x04
225 #define	RX_IBUF_OVERFLOWED	0x08
226 #define	RX_ANY_BLOCK		0x0f
227 			zst_tx_busy,	/* working on an output chunk */
228 			zst_tx_done,	/* done with one output chunk */
229 			zst_tx_stopped,	/* H/W level stop (lost CTS) */
230 			zst_st_check,	/* got a status interrupt */
231 			zst_rx_ready;
232 
233 	/* PPS signal on DCD, with or without inkernel clock disciplining */
234 	uint8_t  zst_ppsmask;			/* pps signal mask */
235 	struct pps_state zst_pps_state;
236 };
237 
238 /* Definition of the driver for autoconfig. */
239 static int	zstty_match(device_t, cfdata_t, void *);
240 static void	zstty_attach(device_t, device_t, void *);
241 
242 CFATTACH_DECL_NEW(zstty, sizeof(struct zstty_softc),
243     zstty_match, zstty_attach, NULL, NULL);
244 
245 dev_type_open(zsopen);
246 dev_type_close(zsclose);
247 dev_type_read(zsread);
248 dev_type_write(zswrite);
249 dev_type_ioctl(zsioctl);
250 dev_type_stop(zsstop);
251 dev_type_tty(zstty);
252 dev_type_poll(zspoll);
253 
254 const struct cdevsw zstty_cdevsw = {
255 	zsopen, zsclose, zsread, zswrite, zsioctl,
256 	zsstop, zstty, zspoll, nommap, ttykqfilter, D_TTY
257 };
258 
259 struct zsops zsops_tty;
260 
261 static void zs_shutdown(struct zstty_softc *);
262 static void	zsstart(struct tty *);
263 static int	zsparam(struct tty *, struct termios *);
264 static void zs_modem(struct zstty_softc *, int);
265 static void tiocm_to_zs(struct zstty_softc *, u_long, int);
266 static int  zs_to_tiocm(struct zstty_softc *);
267 static int    zshwiflow(struct tty *, int);
268 static void  zs_hwiflow(struct zstty_softc *);
269 static void zs_maskintr(struct zstty_softc *);
270 
271 /* Low-level routines. */
272 static void zstty_rxint  (struct zs_chanstate *);
273 static void zstty_stint  (struct zs_chanstate *, int);
274 static void zstty_txint  (struct zs_chanstate *);
275 static void zstty_softint(struct zs_chanstate *);
276 static void zstty_softint1(struct zs_chanstate *);
277 
278 #define	ZSUNIT(x)	(minor(x) & 0x7ffff)
279 #define	ZSDIALOUT(x)	(minor(x) & 0x80000)
280 
281 struct tty *zstty_get_tty_from_dev(device_t);
282 
283 /*
284  * XXX get the (struct tty *) out of a (device_t) we trust to be a
285  * (struct zstty_softc *) - needed by sparc/dev/zs.c, sparc64/dev/zs.c,
286  * sun3/dev/zs.c and sun2/dev/zs.c will probably need it at some point
287  */
288 
289 struct tty *
290 zstty_get_tty_from_dev(device_t dev)
291 {
292 	struct zstty_softc *sc = device_private(dev);
293 
294 	return sc->zst_tty;
295 }
296 
297 /*
298  * zstty_match: how is this zs channel configured?
299  */
300 int
301 zstty_match(device_t parent, cfdata_t cf, void *aux)
302 {
303 	struct zsc_attach_args *args = aux;
304 
305 	/* Exact match is better than wildcard. */
306 	if (cf->zsccf_channel == args->channel)
307 		return 2;
308 
309 	/* This driver accepts wildcard. */
310 	if (cf->zsccf_channel == ZSCCF_CHANNEL_DEFAULT)
311 		return 1;
312 
313 	return 0;
314 }
315 
316 void
317 zstty_attach(device_t parent, device_t self, void *aux)
318 {
319 	struct zstty_softc *zst = device_private(self);
320 	struct zsc_softc *zsc = device_private(parent);
321 	cfdata_t cf = device_cfdata(self);
322 	struct zsc_attach_args *args = aux;
323 	struct zs_chanstate *cs;
324 	struct tty *tp;
325 	int channel, tty_unit;
326 	dev_t dev;
327 	const char *i, *o;
328 	int dtr_on;
329 	int resetbit;
330 
331 	zst->zst_dev = self;
332 
333 	callout_init(&zst->zst_diag_ch, 0);
334 	cn_init_magic(&zstty_cnm_state);
335 
336 	tty_unit = device_unit(self);
337 	channel = args->channel;
338 	cs = zsc->zsc_cs[channel];
339 	cs->cs_private = zst;
340 	cs->cs_ops = &zsops_tty;
341 
342 	zst->zst_cs = cs;
343 	zst->zst_swflags = cf->cf_flags;	/* softcar, etc. */
344 	zst->zst_hwflags = args->hwflags;
345 	dev = makedev(cdevsw_lookup_major(&zstty_cdevsw), tty_unit);
346 
347 	if (zst->zst_swflags)
348 		aprint_normal(" flags 0x%x", zst->zst_swflags);
349 
350 	/*
351 	 * Check whether we serve as a console device.
352 	 * XXX - split console input/output channels aren't
353 	 *	 supported yet on /dev/console
354 	 */
355 	i = o = NULL;
356 	if ((zst->zst_hwflags & ZS_HWFLAG_CONSOLE_INPUT) != 0) {
357 		i = "input";
358 		if ((args->hwflags & ZS_HWFLAG_USE_CONSDEV) != 0) {
359 			args->consdev->cn_dev = dev;
360 			cn_tab->cn_pollc = args->consdev->cn_pollc;
361 			cn_tab->cn_getc = args->consdev->cn_getc;
362 		}
363 		cn_tab->cn_dev = dev;
364 		/* Set console magic to BREAK */
365 		cn_set_magic("\047\001");
366 	}
367 	if ((zst->zst_hwflags & ZS_HWFLAG_CONSOLE_OUTPUT) != 0) {
368 		o = "output";
369 		if ((args->hwflags & ZS_HWFLAG_USE_CONSDEV) != 0) {
370 			cn_tab->cn_putc = args->consdev->cn_putc;
371 		}
372 		cn_tab->cn_dev = dev;
373 	}
374 	if (i != NULL || o != NULL)
375 		aprint_normal(" (console %s)", i ? (o ? "i/o" : i) : o);
376 
377 #ifdef KGDB
378 	if (zs_check_kgdb(cs, dev)) {
379 		/*
380 		 * Allow kgdb to "take over" this port.  Returns true
381 		 * if this serial port is in-use by kgdb.
382 		 */
383 		aprint_normal(" (kgdb)\n");
384 		/*
385 		 * This is the kgdb port (exclusive use)
386 		 * so skip the normal attach code.
387 		 */
388 		return;
389 	}
390 #endif
391 	aprint_normal("\n");
392 
393 	tp = ttymalloc();
394 	tp->t_dev = dev;
395 	tp->t_oproc = zsstart;
396 	tp->t_param = zsparam;
397 	tp->t_hwiflow = zshwiflow;
398 	tty_attach(tp);
399 
400 	zst->zst_tty = tp;
401 	zst->zst_rbuf = malloc(zstty_rbuf_size << 1, M_DEVBUF, M_NOWAIT);
402 	if (zst->zst_rbuf == NULL) {
403 		aprint_error_dev(zst->zst_dev,
404 		    "unable to allocate ring buffer\n");
405 		return;
406 	}
407 	zst->zst_ebuf = zst->zst_rbuf + (zstty_rbuf_size << 1);
408 	/* Disable the high water mark. */
409 	zst->zst_r_hiwat = 0;
410 	zst->zst_r_lowat = 0;
411 	zst->zst_rbget = zst->zst_rbput = zst->zst_rbuf;
412 	zst->zst_rbavail = zstty_rbuf_size;
413 
414 	/* if there are no enable/disable functions, assume the device
415 	   is always enabled */
416 	if (!cs->enable)
417 		cs->enabled = 1;
418 
419 	/*
420 	 * Hardware init
421 	 */
422 	dtr_on = 0;
423 	resetbit = 0;
424 	if (ISSET(zst->zst_hwflags, ZS_HWFLAG_CONSOLE)) {
425 		/* Call zsparam similar to open. */
426 		struct termios t;
427 
428 		/* Wait a while for previous console output to complete */
429 		DELAY(10000);
430 
431 		/* Setup the "new" parameters in t. */
432 		t.c_ispeed = 0;
433 		t.c_ospeed = cs->cs_defspeed;
434 		t.c_cflag = cs->cs_defcflag;
435 
436 		/*
437 		 * Turn on receiver and status interrupts.
438 		 * We defer the actual write of the register to zsparam(),
439 		 * but we must make sure status interrupts are turned on by
440 		 * the time zsparam() reads the initial rr0 state.
441 		 */
442 		SET(cs->cs_preg[1], ZSWR1_RIE | ZSWR1_TIE | ZSWR1_SIE);
443 
444 		/* Make sure zsparam will see changes. */
445 		tp->t_ospeed = 0;
446 		(void) zsparam(tp, &t);
447 
448 		/* Make sure DTR is on now. */
449 		dtr_on = 1;
450 
451 	} else if (!ISSET(zst->zst_hwflags, ZS_HWFLAG_NORESET)) {
452 		/* Not the console; may need reset. */
453 		resetbit = (channel == 0) ? ZSWR9_A_RESET : ZSWR9_B_RESET;
454 	}
455 
456 	mutex_spin_enter(&cs->cs_lock);
457 	if (resetbit)
458 		zs_write_reg(cs, 9, resetbit);
459 	zs_modem(zst, dtr_on);
460 	mutex_spin_exit(&cs->cs_lock);
461 }
462 
463 
464 /*
465  * Return pointer to our tty.
466  */
467 struct tty *
468 zstty(dev_t dev)
469 {
470 	struct zstty_softc *zst;
471 
472 	zst = device_lookup_private(&zstty_cd, ZSUNIT(dev));
473 
474 	return (zst->zst_tty);
475 }
476 
477 
478 void
479 zs_shutdown(struct zstty_softc *zst)
480 {
481 	struct zs_chanstate *cs = zst->zst_cs;
482 	struct tty *tp = zst->zst_tty;
483 
484 	mutex_spin_enter(&cs->cs_lock);
485 
486 	/* If we were asserting flow control, then deassert it. */
487 	SET(zst->zst_rx_flags, RX_IBUF_BLOCKED);
488 	zs_hwiflow(zst);
489 
490 	/* Clear any break condition set with TIOCSBRK. */
491 	zs_break(cs, 0);
492 
493 	/*
494 	 * Hang up if necessary.  Wait a bit, so the other side has time to
495 	 * notice even if we immediately open the port again.
496 	 */
497 	if (ISSET(tp->t_cflag, HUPCL)) {
498 		zs_modem(zst, 0);
499 		mutex_spin_exit(&cs->cs_lock);
500 		/*
501 		 * XXX -    another process is not prevented from opening
502 		 *	    the device during our sleep.
503 		 */
504 		(void) tsleep(cs, TTIPRI, ttclos, hz);
505 		/* Re-check state in case we were opened during our sleep */
506 		if (ISSET(tp->t_state, TS_ISOPEN) || tp->t_wopen != 0)
507 			return;
508 
509 		mutex_spin_enter(&cs->cs_lock);
510 	}
511 
512 	/* Turn off interrupts if not the console. */
513 	if (!ISSET(zst->zst_hwflags, ZS_HWFLAG_CONSOLE)) {
514 		CLR(cs->cs_preg[1], ZSWR1_RIE | ZSWR1_TIE | ZSWR1_SIE);
515 		cs->cs_creg[1] = cs->cs_preg[1];
516 		zs_write_reg(cs, 1, cs->cs_creg[1]);
517 	}
518 
519 	/* Call the power management hook. */
520 	if (cs->disable) {
521 #ifdef DIAGNOSTIC
522 		if (!cs->enabled)
523 			panic("%s: not enabled?", __func__);
524 #endif
525 		(*cs->disable)(zst->zst_cs);
526 	}
527 
528 	mutex_spin_exit(&cs->cs_lock);
529 }
530 
531 /*
532  * Open a zs serial (tty) port.
533  */
534 int
535 zsopen(dev_t dev, int flags, int mode, struct lwp *l)
536 {
537 	struct zstty_softc *zst;
538 	struct zs_chanstate *cs;
539 	struct tty *tp;
540 	int error;
541 
542 	zst = device_lookup_private(&zstty_cd, ZSUNIT(dev));
543 	if (zst == NULL)
544 		return (ENXIO);
545 
546 	tp = zst->zst_tty;
547 	cs = zst->zst_cs;
548 
549 	/* If KGDB took the line, then tp==NULL */
550 	if (tp == NULL)
551 		return (EBUSY);
552 
553 	if (kauth_authorize_device_tty(l->l_cred, KAUTH_DEVICE_TTY_OPEN, tp))
554 		return (EBUSY);
555 
556 	mutex_spin_enter(&tty_lock);
557 
558 	/*
559 	 * Do the following iff this is a first open.
560 	 */
561 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
562 		struct termios t;
563 
564 		tp->t_dev = dev;
565 
566 		/* Call the power management hook. */
567 		if (cs->enable) {
568 			if ((*cs->enable)(cs)) {
569 				mutex_spin_exit(&tty_lock);
570 				printf("%s: device enable failed\n",
571 				    device_xname(zst->zst_dev));
572 				return (EIO);
573 			}
574 		}
575 
576 		/*
577 		 * Initialize the termios status to the defaults.  Add in the
578 		 * sticky bits from TIOCSFLAGS.
579 		 */
580 		t.c_ispeed = 0;
581 		t.c_ospeed = cs->cs_defspeed;
582 		t.c_cflag = cs->cs_defcflag;
583 		if (ISSET(zst->zst_swflags, TIOCFLAG_CLOCAL))
584 			SET(t.c_cflag, CLOCAL);
585 		if (ISSET(zst->zst_swflags, TIOCFLAG_CRTSCTS))
586 			SET(t.c_cflag, CRTSCTS);
587 		if (ISSET(zst->zst_swflags, TIOCFLAG_CDTRCTS))
588 			SET(t.c_cflag, CDTRCTS);
589 		if (ISSET(zst->zst_swflags, TIOCFLAG_MDMBUF))
590 			SET(t.c_cflag, MDMBUF);
591 
592 		mutex_spin_enter(&cs->cs_lock);
593 
594 		/*
595 		 * Turn on receiver and status interrupts.
596 		 * We defer the actual write of the register to zsparam(),
597 		 * but we must make sure status interrupts are turned on by
598 		 * the time zsparam() reads the initial rr0 state.
599 		 */
600 		SET(cs->cs_preg[1], ZSWR1_RIE | ZSWR1_TIE | ZSWR1_SIE);
601 
602 		/* Clear PPS capture state on first open. */
603 		mutex_spin_enter(&timecounter_lock);
604 		zst->zst_ppsmask = 0;
605 		memset(&zst->zst_pps_state, 0, sizeof(zst->zst_pps_state));
606 		zst->zst_pps_state.ppscap =
607 		    PPS_CAPTUREASSERT | PPS_CAPTURECLEAR;
608 		pps_init(&zst->zst_pps_state);
609 		mutex_spin_exit(&timecounter_lock);
610 
611 		mutex_spin_exit(&cs->cs_lock);
612 
613 		/* Make sure zsparam will see changes. */
614 		tp->t_ospeed = 0;
615 		(void) zsparam(tp, &t);
616 
617 		/*
618 		 * Note: zsparam has done: cflag, ispeed, ospeed
619 		 * so we just need to do: iflag, oflag, lflag, cc
620 		 * For "raw" mode, just leave all zeros.
621 		 */
622 		if (!ISSET(zst->zst_hwflags, ZS_HWFLAG_RAW)) {
623 			tp->t_iflag = TTYDEF_IFLAG;
624 			tp->t_oflag = TTYDEF_OFLAG;
625 			tp->t_lflag = TTYDEF_LFLAG;
626 		} else {
627 			tp->t_iflag = 0;
628 			tp->t_oflag = 0;
629 			tp->t_lflag = 0;
630 		}
631 		ttychars(tp);
632 		ttsetwater(tp);
633 
634 		mutex_spin_enter(&cs->cs_lock);
635 
636 		/*
637 		 * Turn on DTR.  We must always do this, even if carrier is not
638 		 * present, because otherwise we'd have to use TIOCSDTR
639 		 * immediately after setting CLOCAL, which applications do not
640 		 * expect.  We always assert DTR while the device is open
641 		 * unless explicitly requested to deassert it.
642 		 */
643 		zs_modem(zst, 1);
644 
645 		/* Clear the input ring, and unblock. */
646 		zst->zst_rbget = zst->zst_rbput = zst->zst_rbuf;
647 		zst->zst_rbavail = zstty_rbuf_size;
648 		zs_iflush(cs);
649 		CLR(zst->zst_rx_flags, RX_ANY_BLOCK);
650 		zs_hwiflow(zst);
651 
652 		mutex_spin_exit(&cs->cs_lock);
653 	}
654 
655 	mutex_spin_exit(&tty_lock);
656 
657 	error = ttyopen(tp, ZSDIALOUT(dev), ISSET(flags, O_NONBLOCK));
658 	if (error)
659 		goto bad;
660 
661 	error = (*tp->t_linesw->l_open)(dev, tp);
662 	if (error)
663 		goto bad;
664 
665 	return (0);
666 
667 bad:
668 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
669 		/*
670 		 * We failed to open the device, and nobody else had it opened.
671 		 * Clean up the state as appropriate.
672 		 */
673 		zs_shutdown(zst);
674 	}
675 
676 	return (error);
677 }
678 
679 /*
680  * Close a zs serial port.
681  */
682 int
683 zsclose(dev_t dev, int flags, int mode, struct lwp *l)
684 {
685 	struct zstty_softc *zst;
686 	struct tty *tp;
687 
688 	zst = device_lookup_private(&zstty_cd, ZSUNIT(dev));
689 	tp = zst->zst_tty;
690 
691 	/* XXX This is for cons.c. */
692 	if (!ISSET(tp->t_state, TS_ISOPEN))
693 		return 0;
694 
695 	(*tp->t_linesw->l_close)(tp, flags);
696 	ttyclose(tp);
697 
698 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
699 		/*
700 		 * Although we got a last close, the device may still be in
701 		 * use; e.g. if this was the dialout node, and there are still
702 		 * processes waiting for carrier on the non-dialout node.
703 		 */
704 		zs_shutdown(zst);
705 	}
706 
707 	return (0);
708 }
709 
710 /*
711  * Read/write zs serial port.
712  */
713 int
714 zsread(dev_t dev, struct uio *uio, int flags)
715 {
716 	struct zstty_softc *zst;
717 	struct tty *tp;
718 
719 	zst = device_lookup_private(&zstty_cd, ZSUNIT(dev));
720 	tp = zst->zst_tty;
721 
722 	return ((*tp->t_linesw->l_read)(tp, uio, flags));
723 }
724 
725 int
726 zswrite(dev_t dev, struct uio *uio, int flags)
727 {
728 	struct zstty_softc *zst;
729 	struct tty *tp;
730 
731 	zst = device_lookup_private(&zstty_cd, ZSUNIT(dev));
732 	tp = zst->zst_tty;
733 
734 	return ((*tp->t_linesw->l_write)(tp, uio, flags));
735 }
736 
737 int
738 zspoll(dev_t dev, int events, struct lwp *l)
739 {
740 	struct zstty_softc *zst;
741 	struct tty *tp;
742 
743 	zst = device_lookup_private(&zstty_cd, ZSUNIT(dev));
744 	tp = zst->zst_tty;
745 
746 	return ((*tp->t_linesw->l_poll)(tp, events, l));
747 }
748 
749 int
750 zsioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l)
751 {
752 	struct zstty_softc *zst;
753 	struct zs_chanstate *cs;
754 	struct tty *tp;
755 	int error;
756 
757 	zst = device_lookup_private(&zstty_cd, ZSUNIT(dev));
758 	cs = zst->zst_cs;
759 	tp = zst->zst_tty;
760 	error = (*tp->t_linesw->l_ioctl)(tp, cmd, data, flag, l);
761 	if (error != EPASSTHROUGH)
762 		return (error);
763 
764 	error = ttioctl(tp, cmd, data, flag, l);
765 	if (error != EPASSTHROUGH)
766 		return (error);
767 
768 #ifdef	ZS_MD_IOCTL
769 	error = ZS_MD_IOCTL(cs, cmd, data);
770 	if (error != EPASSTHROUGH)
771 		return (error);
772 #endif	/* ZS_MD_IOCTL */
773 
774 	error = 0;
775 
776 	mutex_spin_enter(&cs->cs_lock);
777 
778 	switch (cmd) {
779 	case TIOCSBRK:
780 		zs_break(cs, 1);
781 		break;
782 
783 	case TIOCCBRK:
784 		zs_break(cs, 0);
785 		break;
786 
787 	case TIOCGFLAGS:
788 		*(int *)data = zst->zst_swflags;
789 		break;
790 
791 	case TIOCSFLAGS:
792 		error = kauth_authorize_device_tty(l->l_cred,
793 			KAUTH_DEVICE_TTY_PRIVSET, tp);
794 		if (error)
795 			break;
796 		zst->zst_swflags = *(int *)data;
797 		break;
798 
799 	case TIOCSDTR:
800 		zs_modem(zst, 1);
801 		break;
802 
803 	case TIOCCDTR:
804 		zs_modem(zst, 0);
805 		break;
806 
807 	case TIOCMSET:
808 	case TIOCMBIS:
809 	case TIOCMBIC:
810 		tiocm_to_zs(zst, cmd, *(int *)data);
811 		break;
812 
813 	case TIOCMGET:
814 		*(int *)data = zs_to_tiocm(zst);
815 		break;
816 
817 	case PPS_IOC_CREATE:
818 	case PPS_IOC_DESTROY:
819 	case PPS_IOC_GETPARAMS:
820 	case PPS_IOC_SETPARAMS:
821 	case PPS_IOC_GETCAP:
822 	case PPS_IOC_FETCH:
823 #ifdef PPS_SYNC
824 	case PPS_IOC_KCBIND:
825 #endif
826 		mutex_spin_enter(&timecounter_lock);
827 		error = pps_ioctl(cmd, data, &zst->zst_pps_state);
828 		if (zst->zst_pps_state.ppsparam.mode & PPS_CAPTUREBOTH)
829 			zst->zst_ppsmask = ZSRR0_DCD;
830 		else
831 			zst->zst_ppsmask = 0;
832 		mutex_spin_exit(&timecounter_lock);
833 		break;
834 
835 	case TIOCDCDTIMESTAMP:	/* XXX old, overloaded  API used by xntpd v3 */
836 		if (cs->cs_rr0_pps == 0) {
837 			error = EINVAL;
838 			break;
839 		}
840 		mutex_spin_enter(&timecounter_lock);
841 #ifndef PPS_TRAILING_EDGE
842 		TIMESPEC_TO_TIMEVAL((struct timeval *)data,
843 		    &zst->zst_pps_state.ppsinfo.assert_timestamp);
844 #else
845 		TIMESPEC_TO_TIMEVAL((struct timeval *)data,
846 		    &zst->zst_pps_state.ppsinfo.clear_timestamp);
847 #endif
848 		mutex_spin_exit(&timecounter_lock);
849 		/*
850 		 * Now update interrupts.
851 		 */
852 		zs_maskintr(zst);
853 		/*
854 		 * If nothing is being transmitted, set up new current values,
855 		 * else mark them as pending.
856 		 */
857 		if (!cs->cs_heldchange) {
858 			if (zst->zst_tx_busy) {
859 				zst->zst_heldtbc = zst->zst_tbc;
860 				zst->zst_tbc = 0;
861 				cs->cs_heldchange = 1;
862 			} else
863 				zs_loadchannelregs(cs);
864 		}
865 
866 		break;
867 
868 	default:
869 		error = EPASSTHROUGH;
870 		break;
871 	}
872 
873 	mutex_spin_exit(&cs->cs_lock);
874 
875 	return (error);
876 }
877 
878 /*
879  * Start or restart transmission.
880  */
881 static void
882 zsstart(struct tty *tp)
883 {
884 	struct zstty_softc *zst;
885 	struct zs_chanstate *cs;
886 	u_char *tba;
887 	int tbc;
888 
889 	zst = device_lookup_private(&zstty_cd, ZSUNIT(tp->t_dev));
890 	cs = zst->zst_cs;
891 
892 	if (ISSET(tp->t_state, TS_BUSY | TS_TIMEOUT | TS_TTSTOP))
893 		return;
894 	if (zst->zst_tx_stopped)
895 		return;
896 	if (!ttypull(tp))
897 		return;
898 
899 	/* Grab the first contiguous region of buffer space. */
900 	tba = tp->t_outq.c_cf;
901 	tbc = ndqb(&tp->t_outq, 0);
902 
903 	mutex_spin_enter(&cs->cs_lock);
904 
905 	zst->zst_tba = tba;
906 	zst->zst_tbc = tbc;
907 	SET(tp->t_state, TS_BUSY);
908 	zst->zst_tx_busy = 1;
909 
910 #ifdef ZS_TXDMA
911 	if (zst->zst_tbc > 1) {
912 		zs_dma_setup(cs, zst->zst_tba, zst->zst_tbc);
913 		mutex_spin_exit(&cs->cs_lock);
914 		return;
915 	}
916 #endif
917 
918 	/* Output the first character of the contiguous buffer. */
919 	zs_write_data(cs, *zst->zst_tba);
920 	zst->zst_tbc--;
921 	zst->zst_tba++;
922 
923 	mutex_spin_exit(&cs->cs_lock);
924 }
925 
926 /*
927  * Stop output, e.g., for ^S or output flush.
928  */
929 void
930 zsstop(struct tty *tp, int flag)
931 {
932 	struct zstty_softc *zst;
933 
934 	zst = device_lookup_private(&zstty_cd, ZSUNIT(tp->t_dev));
935 
936 	mutex_spin_enter(&zst->zst_cs->cs_lock);
937 	if (ISSET(tp->t_state, TS_BUSY)) {
938 		/* Stop transmitting at the next chunk. */
939 		zst->zst_tbc = 0;
940 		zst->zst_heldtbc = 0;
941 		if (!ISSET(tp->t_state, TS_TTSTOP))
942 			SET(tp->t_state, TS_FLUSH);
943 	}
944 	mutex_spin_exit(&zst->zst_cs->cs_lock);
945 }
946 
947 /*
948  * Set ZS tty parameters from termios.
949  * XXX - Should just copy the whole termios after
950  * making sure all the changes could be done.
951  */
952 static int
953 zsparam(struct tty *tp, struct termios *t)
954 {
955 	struct zstty_softc *zst;
956 	struct zs_chanstate *cs;
957 	int ospeed;
958 	tcflag_t cflag;
959 	uint8_t tmp3, tmp4, tmp5;
960 	int error;
961 
962 	zst = device_lookup_private(&zstty_cd, ZSUNIT(tp->t_dev));
963 	cs = zst->zst_cs;
964 	ospeed = t->c_ospeed;
965 	cflag = t->c_cflag;
966 
967 	/* Check requested parameters. */
968 	if (ospeed < 0)
969 		return (EINVAL);
970 	if (t->c_ispeed && t->c_ispeed != ospeed)
971 		return (EINVAL);
972 
973 	/*
974 	 * For the console, always force CLOCAL and !HUPCL, so that the port
975 	 * is always active.
976 	 */
977 	if (ISSET(zst->zst_swflags, TIOCFLAG_SOFTCAR) ||
978 	    ISSET(zst->zst_hwflags, ZS_HWFLAG_CONSOLE)) {
979 		SET(cflag, CLOCAL);
980 		CLR(cflag, HUPCL);
981 	}
982 
983 	/*
984 	 * Only whack the UART when params change.
985 	 * Some callers need to clear tp->t_ospeed
986 	 * to make sure initialization gets done.
987 	 */
988 	if (tp->t_ospeed == ospeed &&
989 	    tp->t_cflag == cflag)
990 		return (0);
991 
992 	/*
993 	 * Call MD functions to deal with changed
994 	 * clock modes or H/W flow control modes.
995 	 * The BRG divisor is set now. (reg 12,13)
996 	 */
997 	error = zs_set_speed(cs, ospeed);
998 	if (error)
999 		return (error);
1000 	error = zs_set_modes(cs, cflag);
1001 	if (error)
1002 		return (error);
1003 
1004 	/*
1005 	 * Block interrupts so that state will not
1006 	 * be altered until we are done setting it up.
1007 	 *
1008 	 * Initial values in cs_preg are set before
1009 	 * our attach routine is called.  The master
1010 	 * interrupt enable is handled by zsc.c
1011 	 *
1012 	 */
1013 	mutex_spin_enter(&cs->cs_lock);
1014 
1015 	/*
1016 	 * Recalculate which status ints to enable.
1017 	 */
1018 	zs_maskintr(zst);
1019 
1020 	/* Recompute character size bits. */
1021 	tmp3 = cs->cs_preg[3];
1022 	tmp5 = cs->cs_preg[5];
1023 	CLR(tmp3, ZSWR3_RXSIZE);
1024 	CLR(tmp5, ZSWR5_TXSIZE);
1025 	switch (ISSET(cflag, CSIZE)) {
1026 	case CS5:
1027 		SET(tmp3, ZSWR3_RX_5);
1028 		SET(tmp5, ZSWR5_TX_5);
1029 		break;
1030 	case CS6:
1031 		SET(tmp3, ZSWR3_RX_6);
1032 		SET(tmp5, ZSWR5_TX_6);
1033 		break;
1034 	case CS7:
1035 		SET(tmp3, ZSWR3_RX_7);
1036 		SET(tmp5, ZSWR5_TX_7);
1037 		break;
1038 	case CS8:
1039 		SET(tmp3, ZSWR3_RX_8);
1040 		SET(tmp5, ZSWR5_TX_8);
1041 		break;
1042 	}
1043 	cs->cs_preg[3] = tmp3;
1044 	cs->cs_preg[5] = tmp5;
1045 
1046 	/*
1047 	 * Recompute the stop bits and parity bits.  Note that
1048 	 * zs_set_speed() may have set clock selection bits etc.
1049 	 * in wr4, so those must preserved.
1050 	 */
1051 	tmp4 = cs->cs_preg[4];
1052 	CLR(tmp4, ZSWR4_SBMASK | ZSWR4_PARMASK);
1053 	if (ISSET(cflag, CSTOPB))
1054 		SET(tmp4, ZSWR4_TWOSB);
1055 	else
1056 		SET(tmp4, ZSWR4_ONESB);
1057 	if (!ISSET(cflag, PARODD))
1058 		SET(tmp4, ZSWR4_EVENP);
1059 	if (ISSET(cflag, PARENB))
1060 		SET(tmp4, ZSWR4_PARENB);
1061 	cs->cs_preg[4] = tmp4;
1062 
1063 	/* And copy to tty. */
1064 	tp->t_ispeed = 0;
1065 	tp->t_ospeed = ospeed;
1066 	tp->t_cflag = cflag;
1067 
1068 	/*
1069 	 * If nothing is being transmitted, set up new current values,
1070 	 * else mark them as pending.
1071 	 */
1072 	if (!cs->cs_heldchange) {
1073 		if (zst->zst_tx_busy) {
1074 			zst->zst_heldtbc = zst->zst_tbc;
1075 			zst->zst_tbc = 0;
1076 			cs->cs_heldchange = 1;
1077 		} else
1078 			zs_loadchannelregs(cs);
1079 	}
1080 
1081 	/*
1082 	 * If hardware flow control is disabled, turn off the buffer water
1083 	 * marks and unblock any soft flow control state.  Otherwise, enable
1084 	 * the water marks.
1085 	 */
1086 	if (!ISSET(cflag, CHWFLOW)) {
1087 		zst->zst_r_hiwat = 0;
1088 		zst->zst_r_lowat = 0;
1089 		if (ISSET(zst->zst_rx_flags, RX_TTY_OVERFLOWED)) {
1090 			CLR(zst->zst_rx_flags, RX_TTY_OVERFLOWED);
1091 			zst->zst_rx_ready = 1;
1092 			cs->cs_softreq = 1;
1093 		}
1094 		if (ISSET(zst->zst_rx_flags, RX_TTY_BLOCKED|RX_IBUF_BLOCKED)) {
1095 			CLR(zst->zst_rx_flags, RX_TTY_BLOCKED|RX_IBUF_BLOCKED);
1096 			zs_hwiflow(zst);
1097 		}
1098 	} else {
1099 		zst->zst_r_hiwat = zstty_rbuf_hiwat;
1100 		zst->zst_r_lowat = zstty_rbuf_lowat;
1101 	}
1102 
1103 	/*
1104 	 * Force a recheck of the hardware carrier and flow control status,
1105 	 * since we may have changed which bits we're looking at.
1106 	 */
1107 	zstty_stint(cs, 1);
1108 
1109 	mutex_spin_exit(&cs->cs_lock);
1110 
1111 	/*
1112 	 * If hardware flow control is disabled, unblock any hard flow control
1113 	 * state.
1114 	 */
1115 	if (!ISSET(cflag, CHWFLOW)) {
1116 		if (zst->zst_tx_stopped) {
1117 			zst->zst_tx_stopped = 0;
1118 			zsstart(tp);
1119 		}
1120 	}
1121 
1122 	zstty_softint1(cs);
1123 
1124 	return (0);
1125 }
1126 
1127 /*
1128  * Compute interrupt enable bits and set in the pending bits. Called both
1129  * in zsparam() and when PPS (pulse per second timing) state changes.
1130  * Must be called at splzs().
1131  */
1132 static void
1133 zs_maskintr(struct zstty_softc *zst)
1134 {
1135 	struct zs_chanstate *cs = zst->zst_cs;
1136 	uint8_t tmp15;
1137 
1138 	cs->cs_rr0_mask = cs->cs_rr0_cts | cs->cs_rr0_dcd;
1139 	if (zst->zst_ppsmask != 0)
1140 		cs->cs_rr0_mask |= cs->cs_rr0_pps;
1141 	tmp15 = cs->cs_preg[15];
1142 	if (ISSET(cs->cs_rr0_mask, ZSRR0_DCD))
1143 		SET(tmp15, ZSWR15_DCD_IE);
1144 	else
1145 		CLR(tmp15, ZSWR15_DCD_IE);
1146 	if (ISSET(cs->cs_rr0_mask, ZSRR0_CTS))
1147 		SET(tmp15, ZSWR15_CTS_IE);
1148 	else
1149 		CLR(tmp15, ZSWR15_CTS_IE);
1150 	cs->cs_preg[15] = tmp15;
1151 }
1152 
1153 
1154 /*
1155  * Raise or lower modem control (DTR/RTS) signals.  If a character is
1156  * in transmission, the change is deferred.
1157  * Called at splzs() and with the channel lock held.
1158  */
1159 static void
1160 zs_modem(struct zstty_softc *zst, int onoff)
1161 {
1162 	struct zs_chanstate *cs = zst->zst_cs, *ccs;
1163 
1164 	if (cs->cs_wr5_dtr == 0)
1165 		return;
1166 
1167 	ccs = (cs->cs_ctl_chan != NULL ? cs->cs_ctl_chan : cs);
1168 
1169 	if (onoff)
1170 		SET(ccs->cs_preg[5], cs->cs_wr5_dtr);
1171 	else
1172 		CLR(ccs->cs_preg[5], cs->cs_wr5_dtr);
1173 
1174 	if (!cs->cs_heldchange) {
1175 		if (zst->zst_tx_busy) {
1176 			zst->zst_heldtbc = zst->zst_tbc;
1177 			zst->zst_tbc = 0;
1178 			cs->cs_heldchange = 1;
1179 		} else
1180 			zs_loadchannelregs(cs);
1181 	}
1182 }
1183 
1184 /*
1185  * Set modem bits.
1186  * Called at splzs() and with the channel lock held.
1187  */
1188 static void
1189 tiocm_to_zs(struct zstty_softc *zst, u_long how, int ttybits)
1190 {
1191 	struct zs_chanstate *cs = zst->zst_cs, *ccs;
1192 	uint8_t zsbits;
1193 
1194 	ccs = (cs->cs_ctl_chan != NULL ? cs->cs_ctl_chan : cs);
1195 
1196 	zsbits = 0;
1197 	if (ISSET(ttybits, TIOCM_DTR))
1198 		SET(zsbits, ZSWR5_DTR);
1199 	if (ISSET(ttybits, TIOCM_RTS))
1200 		SET(zsbits, ZSWR5_RTS);
1201 
1202 	switch (how) {
1203 	case TIOCMBIC:
1204 		CLR(ccs->cs_preg[5], zsbits);
1205 		break;
1206 
1207 	case TIOCMBIS:
1208 		SET(ccs->cs_preg[5], zsbits);
1209 		break;
1210 
1211 	case TIOCMSET:
1212 		CLR(ccs->cs_preg[5], ZSWR5_RTS | ZSWR5_DTR);
1213 		SET(ccs->cs_preg[5], zsbits);
1214 		break;
1215 	}
1216 
1217 	if (!cs->cs_heldchange) {
1218 		if (zst->zst_tx_busy) {
1219 			zst->zst_heldtbc = zst->zst_tbc;
1220 			zst->zst_tbc = 0;
1221 			cs->cs_heldchange = 1;
1222 		} else
1223 			zs_loadchannelregs(cs);
1224 	}
1225 }
1226 
1227 /*
1228  * Get modem bits.
1229  * Called at splzs() and with the channel lock held.
1230  */
1231 static int
1232 zs_to_tiocm(struct zstty_softc *zst)
1233 {
1234 	struct zs_chanstate *cs = zst->zst_cs, *ccs;
1235 	uint8_t zsbits;
1236 	int ttybits = 0;
1237 
1238 	ccs = (cs->cs_ctl_chan != NULL ? cs->cs_ctl_chan : cs);
1239 
1240 	zsbits = ccs->cs_preg[5];
1241 	if (ISSET(zsbits, ZSWR5_DTR))
1242 		SET(ttybits, TIOCM_DTR);
1243 	if (ISSET(zsbits, ZSWR5_RTS))
1244 		SET(ttybits, TIOCM_RTS);
1245 
1246 	zsbits = cs->cs_rr0;
1247 	if (ISSET(zsbits, ZSRR0_DCD))
1248 		SET(ttybits, TIOCM_CD);
1249 	if (ISSET(zsbits, ZSRR0_CTS))
1250 		SET(ttybits, TIOCM_CTS);
1251 
1252 	return (ttybits);
1253 }
1254 
1255 /*
1256  * Try to block or unblock input using hardware flow-control.
1257  * This is called by kern/tty.c if MDMBUF|CRTSCTS is set, and
1258  * if this function returns non-zero, the TS_TBLOCK flag will
1259  * be set or cleared according to the "block" arg passed.
1260  */
1261 int
1262 zshwiflow(struct tty *tp, int block)
1263 {
1264 	struct zstty_softc *zst;
1265 	struct zs_chanstate *cs;
1266 
1267 	zst = device_lookup_private(&zstty_cd, ZSUNIT(tp->t_dev));
1268 	cs = zst->zst_cs;
1269 
1270 	if (cs->cs_wr5_rts == 0)
1271 		return (0);
1272 
1273 	mutex_spin_enter(&cs->cs_lock);
1274 	if (block) {
1275 		if (!ISSET(zst->zst_rx_flags, RX_TTY_BLOCKED)) {
1276 			SET(zst->zst_rx_flags, RX_TTY_BLOCKED);
1277 			zs_hwiflow(zst);
1278 		}
1279 	} else {
1280 		if (ISSET(zst->zst_rx_flags, RX_TTY_OVERFLOWED)) {
1281 			CLR(zst->zst_rx_flags, RX_TTY_OVERFLOWED);
1282 			zst->zst_rx_ready = 1;
1283 			cs->cs_softreq = 1;
1284 		}
1285 		if (ISSET(zst->zst_rx_flags, RX_TTY_BLOCKED)) {
1286 			CLR(zst->zst_rx_flags, RX_TTY_BLOCKED);
1287 			zs_hwiflow(zst);
1288 		}
1289 	}
1290 	mutex_spin_exit(&cs->cs_lock);
1291 	return (1);
1292 }
1293 
1294 /*
1295  * Internal version of zshwiflow
1296  * Called at splzs() and with the channel lock held.
1297  */
1298 static void
1299 zs_hwiflow(struct zstty_softc *zst)
1300 {
1301 	struct zs_chanstate *cs = zst->zst_cs, *ccs;
1302 
1303 	if (cs->cs_wr5_rts == 0)
1304 		return;
1305 
1306 	ccs = (cs->cs_ctl_chan != NULL ? cs->cs_ctl_chan : cs);
1307 
1308 	if (ISSET(zst->zst_rx_flags, RX_ANY_BLOCK)) {
1309 		CLR(ccs->cs_preg[5], cs->cs_wr5_rts);
1310 		CLR(ccs->cs_creg[5], cs->cs_wr5_rts);
1311 	} else {
1312 		SET(ccs->cs_preg[5], cs->cs_wr5_rts);
1313 		SET(ccs->cs_creg[5], cs->cs_wr5_rts);
1314 	}
1315 	zs_write_reg(ccs, 5, ccs->cs_creg[5]);
1316 }
1317 
1318 
1319 /****************************************************************
1320  * Interface to the lower layer (zscc)
1321  ****************************************************************/
1322 
1323 #define	integrate	static inline
1324 integrate void zstty_rxsoft(struct zstty_softc *, struct tty *);
1325 integrate void zstty_txsoft(struct zstty_softc *, struct tty *);
1326 integrate void zstty_stsoft(struct zstty_softc *, struct tty *);
1327 static void zstty_diag(void *);
1328 
1329 /*
1330  * Receiver Ready interrupt.
1331  * Called at splzs() and with the channel lock held.
1332  */
1333 static void
1334 zstty_rxint(struct zs_chanstate *cs)
1335 {
1336 	struct zstty_softc *zst = cs->cs_private;
1337 	uint8_t *put, *end;
1338 	u_int cc;
1339 	uint8_t rr0, rr1, c;
1340 
1341 	end = zst->zst_ebuf;
1342 	put = zst->zst_rbput;
1343 	cc = zst->zst_rbavail;
1344 
1345 	while (cc > 0) {
1346 		/*
1347 		 * First read the status, because reading the received char
1348 		 * destroys the status of this char.
1349 		 */
1350 		rr1 = zs_read_reg(cs, 1);
1351 		c = zs_read_data(cs);
1352 
1353 		if (ISSET(rr1, ZSRR1_FE | ZSRR1_DO | ZSRR1_PE)) {
1354 			/* Clear the receive error. */
1355 			zs_write_csr(cs, ZSWR0_RESET_ERRORS);
1356 		}
1357 
1358 		cn_check_magic(zst->zst_tty->t_dev, c, zstty_cnm_state);
1359 		put[0] = c;
1360 		put[1] = rr1;
1361 		put += 2;
1362 		if (put >= end)
1363 			put = zst->zst_rbuf;
1364 		cc--;
1365 
1366 		rr0 = zs_read_csr(cs);
1367 		if (!ISSET(rr0, ZSRR0_RX_READY))
1368 			break;
1369 	}
1370 
1371 	/*
1372 	 * Current string of incoming characters ended because
1373 	 * no more data was available or we ran out of space.
1374 	 * Schedule a receive event if any data was received.
1375 	 * If we're out of space, turn off receive interrupts.
1376 	 */
1377 	zst->zst_rbput = put;
1378 	zst->zst_rbavail = cc;
1379 	if (!ISSET(zst->zst_rx_flags, RX_TTY_OVERFLOWED)) {
1380 		zst->zst_rx_ready = 1;
1381 		cs->cs_softreq = 1;
1382 	}
1383 
1384 	/*
1385 	 * See if we are in danger of overflowing a buffer. If
1386 	 * so, use hardware flow control to ease the pressure.
1387 	 */
1388 	if (!ISSET(zst->zst_rx_flags, RX_IBUF_BLOCKED) &&
1389 	    cc < zst->zst_r_hiwat) {
1390 		SET(zst->zst_rx_flags, RX_IBUF_BLOCKED);
1391 		zs_hwiflow(zst);
1392 	}
1393 
1394 	/*
1395 	 * If we're out of space, disable receive interrupts
1396 	 * until the queue has drained a bit.
1397 	 */
1398 	if (!cc) {
1399 		SET(zst->zst_rx_flags, RX_IBUF_OVERFLOWED);
1400 		CLR(cs->cs_preg[1], ZSWR1_RIE);
1401 		cs->cs_creg[1] = cs->cs_preg[1];
1402 		zs_write_reg(cs, 1, cs->cs_creg[1]);
1403 	}
1404 
1405 #if 0
1406 	printf("%xH%04d\n", zst->zst_rx_flags, zst->zst_rbavail);
1407 #endif
1408 }
1409 
1410 /*
1411  * Transmitter Ready interrupt.
1412  * Called at splzs() and with the channel lock held.
1413  */
1414 static void
1415 zstty_txint(struct zs_chanstate *cs)
1416 {
1417 	struct zstty_softc *zst = cs->cs_private;
1418 
1419 	zs_write_csr(cs, ZSWR0_RESET_TXINT);
1420 
1421 	/*
1422 	 * If we've delayed a parameter change, do it now, and restart
1423 	 * output.
1424 	 */
1425 	if (cs->cs_heldchange) {
1426 		zs_loadchannelregs(cs);
1427 		cs->cs_heldchange = 0;
1428 		zst->zst_tbc = zst->zst_heldtbc;
1429 		zst->zst_heldtbc = 0;
1430 	}
1431 
1432 	/* Output the next character in the buffer, if any. */
1433 	if (zst->zst_tbc > 0) {
1434 		zs_write_data(cs, *zst->zst_tba);
1435 		zst->zst_tbc--;
1436 		zst->zst_tba++;
1437 	} else {
1438 		if (zst->zst_tx_busy) {
1439 			zst->zst_tx_busy = 0;
1440 			zst->zst_tx_done = 1;
1441 			cs->cs_softreq = 1;
1442 		}
1443 	}
1444 }
1445 
1446 /*
1447  * Status Change interrupt.
1448  * Called at splzs() and with the channel lock held.
1449  */
1450 static void
1451 zstty_stint(struct zs_chanstate *cs, int force)
1452 {
1453 	struct zstty_softc *zst = cs->cs_private;
1454 	uint8_t rr0, delta;
1455 
1456 	rr0 = zs_read_csr(cs);
1457 	zs_write_csr(cs, ZSWR0_RESET_STATUS);
1458 
1459 	/*
1460 	 * Check here for console break, so that we can abort
1461 	 * even when interrupts are locking up the machine.
1462 	 */
1463 	if (ISSET(rr0, ZSRR0_BREAK))
1464 		cn_check_magic(zst->zst_tty->t_dev, CNC_BREAK, zstty_cnm_state);
1465 
1466 	if (!force)
1467 		delta = rr0 ^ cs->cs_rr0;
1468 	else
1469 		delta = cs->cs_rr0_mask;
1470 	cs->cs_rr0 = rr0;
1471 
1472 	if (ISSET(delta, cs->cs_rr0_mask)) {
1473 		SET(cs->cs_rr0_delta, delta);
1474 
1475 		/*
1476 		 * Pulse-per-second clock signal on edge of DCD?
1477 		 */
1478 		if (ISSET(delta, zst->zst_ppsmask)) {
1479 			if (zst->zst_pps_state.ppsparam.mode &
1480 			    PPS_CAPTUREBOTH) {
1481 				mutex_spin_enter(&timecounter_lock);
1482 				pps_capture(&zst->zst_pps_state);
1483 				pps_event(&zst->zst_pps_state,
1484 				    (ISSET(cs->cs_rr0, zst->zst_ppsmask))
1485 				    ? PPS_CAPTUREASSERT
1486 				    : PPS_CAPTURECLEAR);
1487 				mutex_spin_exit(&timecounter_lock);
1488 			}
1489 		}
1490 
1491 		/*
1492 		 * Stop output immediately if we lose the output
1493 		 * flow control signal or carrier detect.
1494 		 */
1495 		if (ISSET(~rr0, cs->cs_rr0_mask)) {
1496 			zst->zst_tbc = 0;
1497 			zst->zst_heldtbc = 0;
1498 		}
1499 
1500 		zst->zst_st_check = 1;
1501 		cs->cs_softreq = 1;
1502 	}
1503 }
1504 
1505 void
1506 zstty_diag(void *arg)
1507 {
1508 	struct zstty_softc *zst = arg;
1509 	int overflows, floods;
1510 
1511 	mutex_spin_enter(&zst->zst_cs->cs_lock);
1512 	overflows = zst->zst_overflows;
1513 	zst->zst_overflows = 0;
1514 	floods = zst->zst_floods;
1515 	zst->zst_floods = 0;
1516 	zst->zst_errors = 0;
1517 	mutex_spin_exit(&zst->zst_cs->cs_lock);
1518 
1519 	log(LOG_WARNING, "%s: %d silo overflow%s, %d ibuf flood%s\n",
1520 	    device_xname(zst->zst_dev),
1521 	    overflows, overflows == 1 ? "" : "s",
1522 	    floods, floods == 1 ? "" : "s");
1523 }
1524 
1525 integrate void
1526 zstty_rxsoft(struct zstty_softc *zst, struct tty *tp)
1527 {
1528 	struct zs_chanstate *cs = zst->zst_cs;
1529 	int (*rint)(int, struct tty *) = tp->t_linesw->l_rint;
1530 	uint8_t *get, *end;
1531 	u_int cc, scc;
1532 	uint8_t rr1;
1533 	int code;
1534 
1535 	end = zst->zst_ebuf;
1536 	get = zst->zst_rbget;
1537 	scc = cc = zstty_rbuf_size - zst->zst_rbavail;
1538 
1539 	if (cc == zstty_rbuf_size) {
1540 		zst->zst_floods++;
1541 		if (zst->zst_errors++ == 0)
1542 			callout_reset(&zst->zst_diag_ch, 60 * hz,
1543 			    zstty_diag, zst);
1544 	}
1545 
1546 	/* If not yet open, drop the entire buffer content here */
1547 	if (!ISSET(tp->t_state, TS_ISOPEN)) {
1548 		get += cc << 1;
1549 		if (get >= end)
1550 			get -= zstty_rbuf_size << 1;
1551 		cc = 0;
1552 	}
1553 	while (cc) {
1554 		code = get[0];
1555 		rr1 = get[1];
1556 		if (ISSET(rr1, ZSRR1_DO | ZSRR1_FE | ZSRR1_PE)) {
1557 			if (ISSET(rr1, ZSRR1_DO)) {
1558 				zst->zst_overflows++;
1559 				if (zst->zst_errors++ == 0)
1560 					callout_reset(&zst->zst_diag_ch,
1561 					    60 * hz, zstty_diag, zst);
1562 			}
1563 			if (ISSET(rr1, ZSRR1_FE))
1564 				SET(code, TTY_FE);
1565 			if (ISSET(rr1, ZSRR1_PE))
1566 				SET(code, TTY_PE);
1567 		}
1568 		if ((*rint)(code, tp) == -1) {
1569 			/*
1570 			 * The line discipline's buffer is out of space.
1571 			 */
1572 			if (!ISSET(zst->zst_rx_flags, RX_TTY_BLOCKED)) {
1573 				/*
1574 				 * We're either not using flow control, or the
1575 				 * line discipline didn't tell us to block for
1576 				 * some reason.  Either way, we have no way to
1577 				 * know when there's more space available, so
1578 				 * just drop the rest of the data.
1579 				 */
1580 				get += cc << 1;
1581 				if (get >= end)
1582 					get -= zstty_rbuf_size << 1;
1583 				cc = 0;
1584 			} else {
1585 				/*
1586 				 * Don't schedule any more receive processing
1587 				 * until the line discipline tells us there's
1588 				 * space available (through comhwiflow()).
1589 				 * Leave the rest of the data in the input
1590 				 * buffer.
1591 				 */
1592 				SET(zst->zst_rx_flags, RX_TTY_OVERFLOWED);
1593 			}
1594 			break;
1595 		}
1596 		get += 2;
1597 		if (get >= end)
1598 			get = zst->zst_rbuf;
1599 		cc--;
1600 	}
1601 
1602 	if (cc != scc) {
1603 		zst->zst_rbget = get;
1604 		mutex_spin_enter(&cs->cs_lock);
1605 		cc = zst->zst_rbavail += scc - cc;
1606 		/* Buffers should be ok again, release possible block. */
1607 		if (cc >= zst->zst_r_lowat) {
1608 			if (ISSET(zst->zst_rx_flags, RX_IBUF_OVERFLOWED)) {
1609 				CLR(zst->zst_rx_flags, RX_IBUF_OVERFLOWED);
1610 				SET(cs->cs_preg[1], ZSWR1_RIE);
1611 				cs->cs_creg[1] = cs->cs_preg[1];
1612 				zs_write_reg(cs, 1, cs->cs_creg[1]);
1613 			}
1614 			if (ISSET(zst->zst_rx_flags, RX_IBUF_BLOCKED)) {
1615 				CLR(zst->zst_rx_flags, RX_IBUF_BLOCKED);
1616 				zs_hwiflow(zst);
1617 			}
1618 		}
1619 		mutex_spin_exit(&cs->cs_lock);
1620 	}
1621 
1622 #if 0
1623 	printf("%xS%04d\n", zst->zst_rx_flags, zst->zst_rbavail);
1624 #endif
1625 }
1626 
1627 integrate void
1628 zstty_txsoft(struct zstty_softc *zst, struct tty *tp)
1629 {
1630 	struct zs_chanstate *cs = zst->zst_cs;
1631 
1632 	mutex_spin_enter(&cs->cs_lock);
1633 	CLR(tp->t_state, TS_BUSY);
1634 	if (ISSET(tp->t_state, TS_FLUSH))
1635 		CLR(tp->t_state, TS_FLUSH);
1636 	else
1637 		ndflush(&tp->t_outq, (int)(zst->zst_tba - tp->t_outq.c_cf));
1638 	mutex_spin_exit(&cs->cs_lock);
1639 	(*tp->t_linesw->l_start)(tp);
1640 }
1641 
1642 integrate void
1643 zstty_stsoft(struct zstty_softc *zst, struct tty *tp)
1644 {
1645 	struct zs_chanstate *cs = zst->zst_cs;
1646 	uint8_t rr0, delta;
1647 
1648 	mutex_spin_enter(&cs->cs_lock);
1649 	rr0 = cs->cs_rr0;
1650 	delta = cs->cs_rr0_delta;
1651 	cs->cs_rr0_delta = 0;
1652 	mutex_spin_exit(&cs->cs_lock);
1653 
1654 	if (ISSET(delta, cs->cs_rr0_dcd)) {
1655 		/*
1656 		 * Inform the tty layer that carrier detect changed.
1657 		 */
1658 		mutex_spin_exit(&tty_lock);
1659 		(void) (*tp->t_linesw->l_modem)(tp, ISSET(rr0, ZSRR0_DCD));
1660 		mutex_spin_enter(&tty_lock);
1661 	}
1662 
1663 	if (ISSET(delta, cs->cs_rr0_cts)) {
1664 		/* Block or unblock output according to flow control. */
1665 		if (ISSET(rr0, cs->cs_rr0_cts)) {
1666 			zst->zst_tx_stopped = 0;
1667 			(*tp->t_linesw->l_start)(tp);
1668 		} else {
1669 			zst->zst_tx_stopped = 1;
1670 		}
1671 	}
1672 }
1673 
1674 /*
1675  * Software interrupt.  Called at zssoft
1676  *
1677  * The main job to be done here is to empty the input ring
1678  * by passing its contents up to the tty layer.  The ring is
1679  * always emptied during this operation, therefore the ring
1680  * must not be larger than the space after "high water" in
1681  * the tty layer, or the tty layer might drop our input.
1682  *
1683  * Note: an "input blockage" condition is assumed to exist if
1684  * EITHER the TS_TBLOCK flag or zst_rx_blocked flag is set.
1685  */
1686 static void
1687 zstty_softint(struct zs_chanstate *cs)
1688 {
1689 
1690 	zstty_softint1(cs);
1691 }
1692 
1693 static void
1694 zstty_softint1(struct zs_chanstate *cs)
1695 {
1696 	struct zstty_softc *zst = cs->cs_private;
1697 	struct tty *tp = zst->zst_tty;
1698 
1699 
1700 	if (zst->zst_rx_ready) {
1701 		zst->zst_rx_ready = 0;
1702 		zstty_rxsoft(zst, tp);
1703 	}
1704 
1705 	if (zst->zst_st_check) {
1706 		zst->zst_st_check = 0;
1707 		zstty_stsoft(zst, tp);
1708 	}
1709 
1710 	if (zst->zst_tx_done) {
1711 		zst->zst_tx_done = 0;
1712 		zstty_txsoft(zst, tp);
1713 	}
1714 }
1715 
1716 struct zsops zsops_tty = {
1717 	zstty_rxint,	/* receive char available */
1718 	zstty_stint,	/* external/status */
1719 	zstty_txint,	/* xmit buffer empty */
1720 	zstty_softint,	/* process software interrupt */
1721 };
1722 
1723 #ifdef ZS_TXDMA
1724 void
1725 zstty_txdma_int(void *arg)
1726 {
1727 	struct zs_chanstate *cs = arg;
1728 	struct zstty_softc *zst = cs->cs_private;
1729 
1730 	zst->zst_tba += zst->zst_tbc;
1731 	zst->zst_tbc = 0;
1732 
1733 	if (zst->zst_tx_busy) {
1734 		zst->zst_tx_busy = 0;
1735 		zst->zst_tx_done = 1;
1736 		cs->cs_softreq = 1;
1737 	}
1738 }
1739 #endif
1740