xref: /openbsd/sys/dev/ic/z8530tty.c (revision 8544fed6)
1 /*	$OpenBSD: z8530tty.c,v 1.32 2020/01/09 14:35:19 mpi Exp $	*/
2 /*	$NetBSD: z8530tty.c,v 1.77 2001/05/30 15:24:24 lukem Exp $	*/
3 
4 /*-
5  * Copyright (c) 1993, 1994, 1995, 1996, 1997, 1998, 1999
6  *	Charles M. Hannum.  All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *	This product includes software developed by Charles M. Hannum.
19  * 4. The name of the author may not be used to endorse or promote products
20  *    derived from this software without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
23  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
24  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
25  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
26  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
27  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
29  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
31  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 /*
35  * Copyright (c) 1994 Gordon W. Ross
36  * Copyright (c) 1992, 1993
37  *	The Regents of the University of California.  All rights reserved.
38  *
39  * This software was developed by the Computer Systems Engineering group
40  * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
41  * contributed to Berkeley.
42  *
43  * All advertising materials mentioning features or use of this software
44  * must display the following acknowledgement:
45  *	This product includes software developed by the University of
46  *	California, Lawrence Berkeley Laboratory.
47  *
48  * Redistribution and use in source and binary forms, with or without
49  * modification, are permitted provided that the following conditions
50  * are met:
51  * 1. Redistributions of source code must retain the above copyright
52  *    notice, this list of conditions and the following disclaimer.
53  * 2. Redistributions in binary form must reproduce the above copyright
54  *    notice, this list of conditions and the following disclaimer in the
55  *    documentation and/or other materials provided with the distribution.
56  * 3. Neither the name of the University nor the names of its contributors
57  *    may be used to endorse or promote products derived from this software
58  *    without specific prior written permission.
59  *
60  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
61  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
62  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
63  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
64  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
65  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
66  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
67  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
68  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
69  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
70  * SUCH DAMAGE.
71  *
72  *	@(#)zs.c	8.1 (Berkeley) 7/19/93
73  */
74 
75 /*
76  * Zilog Z8530 Dual UART driver (tty interface)
77  *
78  * This is the "slave" driver that will be attached to
79  * the "zsc" driver for plain "tty" async. serial lines.
80  *
81  * Credits, history:
82  *
83  * The original version of this code was the sparc/dev/zs.c driver
84  * as distributed with the Berkeley 4.4 Lite release.  Since then,
85  * Gordon Ross reorganized the code into the current parent/child
86  * driver scheme, separating the Sun keyboard and mouse support
87  * into independent child drivers.
88  *
89  * RTS/CTS flow-control support was a collaboration of:
90  *	Gordon Ross <gwr@NetBSD.org>,
91  *	Bill Studenmund <wrstuden@loki.stanford.edu>
92  *	Ian Dall <Ian.Dall@dsto.defence.gov.au>
93  *
94  * The driver was massively overhauled in November 1997 by Charles Hannum,
95  * fixing *many* bugs, and substantially improving performance.
96  */
97 
98 #include <sys/param.h>
99 #include <sys/systm.h>
100 #include <sys/proc.h>
101 #include <sys/device.h>
102 #include <sys/conf.h>
103 #include <sys/fcntl.h>
104 #include <sys/ioctl.h>
105 #include <sys/malloc.h>
106 #include <sys/tty.h>
107 #include <sys/time.h>
108 #include <sys/kernel.h>
109 #include <sys/syslog.h>
110 
111 #include <dev/ic/z8530reg.h>
112 #include <machine/z8530var.h>
113 
114 #include <dev/cons.h>
115 
116 /*
117  * Allow the MD var.h to override the default CFLAG so that
118  * console messages during boot come out with correct parity.
119  */
120 #ifndef	ZSTTY_DEF_CFLAG
121 #define	ZSTTY_DEF_CFLAG	TTYDEF_CFLAG
122 #endif
123 
124 /*
125  * How many input characters we can buffer.
126  * The port-specific var.h may override this.
127  * Note: must be a power of two!
128  */
129 #ifndef	ZSTTY_RING_SIZE
130 #define	ZSTTY_RING_SIZE	2048
131 #endif
132 
133 struct cfdriver zstty_cd = {
134 	NULL, "zstty", DV_TTY
135 };
136 
137 /*
138  * Make this an option variable one can patch.
139  * But be warned:  this must be a power of 2!
140  */
141 u_int zstty_rbuf_size = ZSTTY_RING_SIZE;
142 
143 /* Stop input when 3/4 of the ring is full; restart when only 1/4 is full. */
144 u_int zstty_rbuf_hiwat = (ZSTTY_RING_SIZE * 1) / 4;
145 u_int zstty_rbuf_lowat = (ZSTTY_RING_SIZE * 3) / 4;
146 
147 struct zstty_softc {
148 	struct	device zst_dev;		/* required first: base device */
149 	struct  tty *zst_tty;
150 	struct	zs_chanstate *zst_cs;
151 
152 	struct timeout zst_diag_ch;
153 
154 	u_int zst_overflows,
155 	      zst_floods,
156 	      zst_errors;
157 
158 	int zst_hwflags,	/* see z8530var.h */
159 	    zst_swflags;	/* TIOCFLAG_SOFTCAR, ... <ttycom.h> */
160 
161 	u_int zst_r_hiwat,
162 	      zst_r_lowat;
163 	uint8_t *volatile zst_rbget,
164 		*volatile zst_rbput;
165 	volatile u_int zst_rbavail;
166 	uint8_t *zst_rbuf,
167 		*zst_ebuf;
168 
169 	/*
170 	 * The transmit byte count and address are used for pseudo-DMA
171 	 * output in the hardware interrupt code.  PDMA can be suspended
172 	 * to get pending changes done; heldtbc is used for this.  It can
173 	 * also be stopped for ^S; this sets TS_TTSTOP in tp->t_state.
174 	 */
175 	uint8_t *zst_tba;		/* transmit buffer address */
176 	u_int zst_tbc,			/* transmit byte count */
177 	      zst_heldtbc;		/* held tbc while xmission stopped */
178 
179 	/* Flags to communicate with zstty_softint() */
180 	volatile uint8_t zst_rx_flags,	/* receiver blocked */
181 #define	RX_TTY_BLOCKED		0x01
182 #define	RX_TTY_OVERFLOWED	0x02
183 #define	RX_IBUF_BLOCKED		0x04
184 #define	RX_IBUF_OVERFLOWED	0x08
185 #define	RX_ANY_BLOCK		0x0f
186 			zst_tx_busy,	/* working on an output chunk */
187 			zst_tx_done,	/* done with one output chunk */
188 			zst_tx_stopped,	/* H/W level stop (lost CTS) */
189 			zst_st_check,	/* got a status interrupt */
190 			zst_rx_ready;
191 
192 	/* PPS signal on DCD, with or without inkernel clock disciplining */
193 	uint8_t  zst_ppsmask;			/* pps signal mask */
194 	uint8_t  zst_ppsassert;			/* pps leading edge */
195 	uint8_t  zst_ppsclear;			/* pps trailing edge */
196 };
197 
198 /* Definition of the driver for autoconfig. */
199 int	zstty_match(struct device *, void *, void *);
200 void	zstty_attach(struct device *, struct device *, void *);
201 
202 const struct cfattach zstty_ca = {
203 	sizeof(struct zstty_softc), zstty_match, zstty_attach
204 };
205 
206 cdev_decl(zs);
207 
208 struct zsops zsops_tty;
209 
210 void zs_shutdown(struct zstty_softc *);
211 void	zsstart(struct tty *);
212 int	zsparam(struct tty *, struct termios *);
213 void zs_modem(struct zstty_softc *, int);
214 void tiocm_to_zs(struct zstty_softc *, u_long, int);
215 int  zs_to_tiocm(struct zstty_softc *);
216 int    zshwiflow(struct tty *, int);
217 void  zs_hwiflow(struct zstty_softc *);
218 void zs_maskintr(struct zstty_softc *);
219 
220 struct zstty_softc *zs_device_lookup(struct cfdriver *, int);
221 
222 /* Low-level routines. */
223 void zstty_rxint(struct zs_chanstate *);
224 void zstty_stint(struct zs_chanstate *, int);
225 void zstty_txint(struct zs_chanstate *);
226 void zstty_softint(struct zs_chanstate *);
227 void zstty_diag(void *);
228 
229 #define	ZSUNIT(x)	(minor(x) & 0x7f)
230 #define	ZSDIALOUT(x)	(minor(x) & 0x80)
231 
232 struct zstty_softc *
zs_device_lookup(struct cfdriver * cf,int unit)233 zs_device_lookup(struct cfdriver *cf, int unit)
234 {
235 	return (struct zstty_softc *)device_lookup(cf, unit);
236 }
237 
238 /*
239  * zstty_match: how is this zs channel configured?
240  */
241 int
zstty_match(struct device * parent,void * vcf,void * aux)242 zstty_match(struct device *parent, void *vcf, void *aux)
243 {
244 	struct cfdata *cf = vcf;
245 	struct zsc_attach_args *args = aux;
246 
247 	/* Exact match is better than wildcard. */
248 	if (cf->cf_loc[0] == args->channel)
249 		return 2;
250 
251 	/* This driver accepts wildcard. */
252 	if (cf->cf_loc[0] == -1)
253 		return 1;
254 
255 	return 0;
256 }
257 
258 void
zstty_attach(struct device * parent,struct device * self,void * aux)259 zstty_attach(struct device *parent, struct device *self, void *aux)
260 {
261 	struct zsc_softc *zsc = (struct zsc_softc *)parent;
262 	struct zstty_softc *zst = (struct zstty_softc *)self;
263 	struct cfdata *cf = self->dv_cfdata;
264 	struct zsc_attach_args *args = aux;
265 	struct zs_chanstate *cs;
266 	struct tty *tp;
267 	int channel, s, tty_unit;
268 	dev_t dev;
269 	const char *i, *o;
270 	int dtr_on;
271 	int resetbit;
272 
273 	timeout_set(&zst->zst_diag_ch, zstty_diag, zst);
274 
275 	tty_unit = zst->zst_dev.dv_unit;
276 	channel = args->channel;
277 	cs = zsc->zsc_cs[channel];
278 	cs->cs_private = zst;
279 	cs->cs_ops = &zsops_tty;
280 
281 	zst->zst_cs = cs;
282 	zst->zst_swflags = cf->cf_flags;	/* softcar, etc. */
283 	zst->zst_hwflags = args->hwflags;
284 	dev = makedev(zs_major, tty_unit);
285 
286 	if (zst->zst_swflags)
287 		printf(" flags 0x%x", zst->zst_swflags);
288 
289 	if (ISSET(zst->zst_hwflags, ZS_HWFLAG_NO_DCD))
290 		SET(zst->zst_swflags, TIOCFLAG_SOFTCAR);
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 			args->consdev->cn_dev = dev;
302 			cn_tab->cn_pollc = args->consdev->cn_pollc;
303 			cn_tab->cn_getc = args->consdev->cn_getc;
304 		}
305 		cn_tab->cn_dev = dev;
306 	}
307 	if ((zst->zst_hwflags & ZS_HWFLAG_CONSOLE_OUTPUT) != 0) {
308 		o = " output";
309 		if ((args->hwflags & ZS_HWFLAG_USE_CONSDEV) != 0) {
310 			cn_tab->cn_putc = args->consdev->cn_putc;
311 		}
312 		cn_tab->cn_dev = dev;
313 	}
314 	if (i != NULL || o != NULL) {
315 		printf(": console%s", i ? (o ? "" : i) : o);
316 	}
317 
318 #if defined(__sparc64__)
319 	if (strcmp(args->type, "keyboard") == 0 ||
320 	    strcmp(args->type, "mouse") == 0)
321 		printf(": %s", args->type);
322 #endif
323 
324 	printf("\n");
325 
326 	tp = ttymalloc(0);
327 	tp->t_dev = dev;
328 	tp->t_oproc = zsstart;
329 	tp->t_param = zsparam;
330 	tp->t_hwiflow = zshwiflow;
331 
332 	zst->zst_tty = tp;
333 	zst->zst_rbuf = mallocarray(zstty_rbuf_size, 2, M_DEVBUF, M_WAITOK);
334 	zst->zst_ebuf = zst->zst_rbuf + (zstty_rbuf_size * 2);
335 	/* Disable the high water mark. */
336 	zst->zst_r_hiwat = 0;
337 	zst->zst_r_lowat = 0;
338 	zst->zst_rbget = zst->zst_rbput = zst->zst_rbuf;
339 	zst->zst_rbavail = zstty_rbuf_size;
340 
341 	/* if there are no enable/disable functions, assume the device
342 	   is always enabled */
343 	if (!cs->enable)
344 		cs->enabled = 1;
345 
346 	/*
347 	 * Hardware init
348 	 */
349 	dtr_on = 0;
350 	resetbit = 0;
351 	if (ISSET(zst->zst_hwflags, ZS_HWFLAG_CONSOLE)) {
352 		/* Call zsparam similar to open. */
353 		struct termios t;
354 
355 		/* Wait a while for previous console output to complete */
356 		DELAY(10000);
357 
358 		/* Setup the "new" parameters in t. */
359 		t.c_ispeed = 0;
360 		t.c_ospeed = cs->cs_defspeed;
361 		t.c_cflag = cs->cs_defcflag;
362 
363 		s = splzs();
364 
365 		/*
366 		 * Turn on receiver and status interrupts.
367 		 * We defer the actual write of the register to zsparam(),
368 		 * but we must make sure status interrupts are turned on by
369 		 * the time zsparam() reads the initial rr0 state.
370 		 */
371 		SET(cs->cs_preg[1], ZSWR1_RIE | ZSWR1_TIE | ZSWR1_SIE);
372 
373 		splx(s);
374 
375 		/* Make sure zsparam will see changes. */
376 		tp->t_ospeed = 0;
377 		(void)zsparam(tp, &t);
378 
379 		/* Make sure DTR is on now. */
380 		dtr_on = 1;
381 	} else if (!ISSET(zst->zst_hwflags, ZS_HWFLAG_NORESET)) {
382 		/* Not the console; may need reset. */
383 		resetbit = (channel == 0) ? ZSWR9_A_RESET : ZSWR9_B_RESET;
384 	}
385 
386 	s = splzs();
387 	if (resetbit)
388 		zs_write_reg(cs, 9, resetbit);
389 	zs_modem(zst, dtr_on);
390 	splx(s);
391 }
392 
393 
394 /*
395  * Return pointer to our tty.
396  */
397 struct tty *
zstty(dev_t dev)398 zstty(dev_t dev)
399 {
400 	struct zstty_softc *zst = zs_device_lookup(&zstty_cd, ZSUNIT(dev));
401 
402 	return (zst->zst_tty);
403 }
404 
405 
406 void
zs_shutdown(struct zstty_softc * zst)407 zs_shutdown(struct zstty_softc *zst)
408 {
409 	struct zs_chanstate *cs = zst->zst_cs;
410 	struct tty *tp = zst->zst_tty;
411 	int s;
412 
413 	s = splzs();
414 
415 	/* If we were asserting flow control, then deassert it. */
416 	SET(zst->zst_rx_flags, RX_IBUF_BLOCKED);
417 	zs_hwiflow(zst);
418 
419 	/* Clear any break condition set with TIOCSBRK. */
420 	zs_break(cs, 0);
421 
422 	/* Turn off PPS capture on last close. */
423 	zst->zst_ppsmask = 0;
424 
425 	/*
426 	 * Hang up if necessary.  Wait a bit, so the other side has time to
427 	 * notice even if we immediately open the port again.
428 	 */
429 	if (ISSET(tp->t_cflag, HUPCL) || ISSET(tp->t_state, TS_WOPEN)) {
430 		zs_modem(zst, 0);
431 		/* hold low for 1 second */
432 		tsleep_nsec(cs, TTIPRI, ttclos, SEC_TO_NSEC(1));
433 	}
434 
435 	/* Turn off interrupts if not the console. */
436 	if (!ISSET(zst->zst_hwflags, ZS_HWFLAG_CONSOLE)) {
437 		CLR(cs->cs_preg[1], ZSWR1_RIE | ZSWR1_TIE | ZSWR1_SIE);
438 		cs->cs_creg[1] = cs->cs_preg[1];
439 		zs_write_reg(cs, 1, cs->cs_creg[1]);
440 	}
441 
442 	/* Call the power management hook. */
443 	if (cs->disable) {
444 #ifdef DIAGNOSTIC
445 		if (!cs->enabled)
446 			panic("%s: not enabled?", __func__);
447 #endif
448 		(*cs->disable)(zst->zst_cs);
449 	}
450 
451 	splx(s);
452 }
453 
454 /*
455  * Open a zs serial (tty) port.
456  */
457 int
zsopen(dev_t dev,int flags,int mode,struct proc * p)458 zsopen(dev_t dev, int flags, int mode, struct proc *p)
459 {
460 	struct zstty_softc *zst;
461 	struct zs_chanstate *cs;
462 	struct tty *tp;
463 	int s;
464 #if IPL_ZS != IPL_TTY
465 	int s2;
466 #endif
467 	int error;
468 
469 	zst = zs_device_lookup(&zstty_cd, ZSUNIT(dev));
470 	if (zst == NULL)
471 		return (ENXIO);
472 
473 	tp = zst->zst_tty;
474 	cs = zst->zst_cs;
475 
476 	/* If KGDB took the line, then tp==NULL */
477 	if (tp == NULL)
478 		return (EBUSY);
479 
480 	if (ISSET(tp->t_state, TS_ISOPEN) &&
481 	    ISSET(tp->t_state, TS_XCLUDE) &&
482 	    suser(p) != 0)
483 		return (EBUSY);
484 
485 	s = spltty();
486 
487 	/*
488 	 * Do the following iff this is a first open.
489 	 */
490 	if (!ISSET(tp->t_state, TS_ISOPEN)) {
491 		struct termios t;
492 
493 		tp->t_dev = dev;
494 
495 		/* Call the power management hook. */
496 		if (cs->enable) {
497 			if ((*cs->enable)(cs)) {
498 				splx(s);
499 				printf("%s: device enable failed\n",
500 				    zst->zst_dev.dv_xname);
501 				return (EIO);
502 			}
503 		}
504 
505 		/*
506 		 * Initialize the termios status to the defaults.  Add in the
507 		 * sticky bits from TIOCSFLAGS.
508 		 */
509 		t.c_ispeed = 0;
510 		t.c_ospeed = cs->cs_defspeed;
511 		t.c_cflag = cs->cs_defcflag;
512 		if (ISSET(zst->zst_swflags, TIOCFLAG_CLOCAL))
513 			SET(t.c_cflag, CLOCAL);
514 		if (ISSET(zst->zst_swflags, TIOCFLAG_CRTSCTS))
515 			SET(t.c_cflag, CRTSCTS);
516 		if (ISSET(zst->zst_swflags, TIOCFLAG_MDMBUF))
517 			SET(t.c_cflag, MDMBUF);
518 
519 #if IPL_ZS != IPL_TTY
520 		s2 = splzs();
521 #endif
522 
523 		/*
524 		 * Turn on receiver and status interrupts.
525 		 * We defer the actual write of the register to zsparam(),
526 		 * but we must make sure status interrupts are turned on by
527 		 * the time zsparam() reads the initial rr0 state.
528 		 */
529 		SET(cs->cs_preg[1], ZSWR1_RIE | ZSWR1_TIE | ZSWR1_SIE);
530 
531 		/* Clear PPS capture state on first open. */
532 		zst->zst_ppsmask = 0;
533 
534 #if IPL_ZS != IPL_TTY
535 		splx(s2);
536 #endif
537 
538 		/* Make sure zsparam will see changes. */
539 		tp->t_ospeed = 0;
540 		(void)zsparam(tp, &t);
541 
542 		/*
543 		 * Note: zsparam has done: cflag, ispeed, ospeed
544 		 * so we just need to do: iflag, oflag, lflag, cc
545 		 * For "raw" mode, just leave all zeros.
546 		 */
547 		if (!ISSET(zst->zst_hwflags, ZS_HWFLAG_RAW)) {
548 			tp->t_iflag = TTYDEF_IFLAG;
549 			tp->t_oflag = TTYDEF_OFLAG;
550 			tp->t_lflag = TTYDEF_LFLAG;
551 		} else {
552 			tp->t_iflag = 0;
553 			tp->t_oflag = 0;
554 			tp->t_lflag = 0;
555 		}
556 		ttychars(tp);
557 		ttsetwater(tp);
558 
559 		if (ZSDIALOUT(dev))
560 			SET(tp->t_state, TS_CARR_ON);
561 		else
562 			CLR(tp->t_state, TS_CARR_ON);
563 
564 #if IPL_ZS != IPL_TTY
565 		s2 = splzs();
566 #endif
567 
568 		/* Clear the input ring, and unblock. */
569 		zst->zst_rbget = zst->zst_rbput = zst->zst_rbuf;
570 		zst->zst_rbavail = zstty_rbuf_size;
571 		zs_iflush(cs);
572 		CLR(zst->zst_rx_flags, RX_ANY_BLOCK);
573 		zs_hwiflow(zst);
574 
575 #if IPL_ZS != IPL_TTY
576 		splx(s2);
577 #endif
578 	}
579 
580 	if (ZSDIALOUT(dev)) {
581 		if (ISSET(tp->t_state, TS_ISOPEN)) {
582 			/* someone already is dialed in... */
583 			splx(s);
584 			return EBUSY;
585 		}
586 		cs->cs_cua = 1;
587 	}
588 
589 	error = 0;
590 	/* wait for carrier if necessary */
591 	if (ISSET(flags, O_NONBLOCK)) {
592 		if (!ZSDIALOUT(dev) && cs->cs_cua) {
593 			/* Opening TTY non-blocking... but the CUA is busy */
594 			error = EBUSY;
595 		}
596 	} else
597 	  while (cs->cs_cua ||
598 	    (!ISSET(tp->t_cflag, CLOCAL) && !ISSET(tp->t_state, TS_CARR_ON))) {
599 		int rr0;
600 
601 		error = 0;
602 		SET(tp->t_state, TS_WOPEN);
603 
604 		if (!ZSDIALOUT(dev) && !cs->cs_cua) {
605 			/*
606 			 * Turn on DTR.  We must always do this on non-CUA
607 			 * devices, even if carrier is not present, because
608 			 * otherwise we'd have to use TIOCSDTR immediately
609 			 * after setting CLOCAL, which applications do not
610 			 * expect.  We always assert DTR while the device is
611 			 * open unless explicitly requested to deassert it.
612 			 */
613 #if IPL_ZS != IPL_TTY
614 			s2 = splzs();
615 #endif
616 			zs_modem(zst, 1);
617 			rr0 = zs_read_csr(cs);
618 #if IPL_ZS != IPL_TTY
619 			splx(s2);
620 #endif
621 
622 			/* loop, turning on the device, until carrier present */
623 			if (ISSET(rr0, ZSRR0_DCD) ||
624 			    ISSET(zst->zst_swflags, TIOCFLAG_SOFTCAR))
625 				SET(tp->t_state, TS_CARR_ON);
626 		}
627 
628 		if ((ISSET(tp->t_cflag, CLOCAL) ||
629 		    ISSET(tp->t_state, TS_CARR_ON)) && !cs->cs_cua)
630 			break;
631 
632 		error = ttysleep(tp, (caddr_t)&tp->t_rawq, TTIPRI | PCATCH,
633 		    ttopen);
634 
635 		if (!ZSDIALOUT(dev) && cs->cs_cua && error == EINTR) {
636 			error = 0;
637 			continue;
638 		}
639 
640 		if (error) {
641 			if (!ISSET(tp->t_state, TS_ISOPEN)) {
642 #if IPL_ZS != IPL_TTY
643 				s2 = splzs();
644 #endif
645 				zs_modem(zst, 0);
646 #if IPL_ZS != IPL_TTY
647 				splx(s2);
648 #endif
649 				CLR(tp->t_state, TS_WOPEN);
650 				ttwakeup(tp);
651 			}
652 			if (ZSDIALOUT(dev))
653 				cs->cs_cua = 0;
654 			CLR(tp->t_state, TS_WOPEN);
655 			break;
656 		}
657 		if (!ZSDIALOUT(dev) && cs->cs_cua)
658 			continue;
659 	}
660 
661 	splx(s);
662 
663 	if (error == 0)
664 		error = ((*linesw[tp->t_line].l_open)(dev, tp, p));
665 	if (error)
666 		goto bad;
667 
668 	return (0);
669 
670 bad:
671 	if (!ISSET(tp->t_state, TS_ISOPEN)) {
672 		/*
673 		 * We failed to open the device, and nobody else had it opened.
674 		 * Clean up the state as appropriate.
675 		 */
676 		zs_shutdown(zst);
677 	}
678 
679 	return (error);
680 }
681 
682 /*
683  * Close a zs serial port.
684  */
685 int
zsclose(dev_t dev,int flags,int mode,struct proc * p)686 zsclose(dev_t dev, int flags, int mode, struct proc *p)
687 {
688 	struct zstty_softc *zst = zs_device_lookup(&zstty_cd, ZSUNIT(dev));
689 	struct zs_chanstate *cs = zst->zst_cs;
690 	struct tty *tp = zst->zst_tty;
691 	int s;
692 
693 	/* XXX This is for cons.c. */
694 	if (!ISSET(tp->t_state, TS_ISOPEN))
695 		return 0;
696 
697 	(*linesw[tp->t_line].l_close)(tp, flags, p);
698 
699 	s = spltty();
700 	cs->cs_cua = 0;
701 	ttyclose(tp);
702 	splx(s);
703 
704 	if (!ISSET(tp->t_state, TS_ISOPEN)) {
705 		/*
706 		 * Although we got a last close, the device may still be in
707 		 * use; e.g. if this was the dialout node, and there are still
708 		 * processes waiting for carrier on the non-dialout node.
709 		 */
710 		zs_shutdown(zst);
711 	}
712 
713 	return (0);
714 }
715 
716 /*
717  * Read/write zs serial port.
718  */
719 int
zsread(dev_t dev,struct uio * uio,int flags)720 zsread(dev_t dev, struct uio *uio, int flags)
721 {
722 	struct zstty_softc *zst = zs_device_lookup(&zstty_cd, ZSUNIT(dev));
723 	struct tty *tp = zst->zst_tty;
724 
725 	return (*linesw[tp->t_line].l_read)(tp, uio, flags);
726 }
727 
728 int
zswrite(dev_t dev,struct uio * uio,int flags)729 zswrite(dev_t dev, struct uio *uio, int flags)
730 {
731 	struct zstty_softc *zst = zs_device_lookup(&zstty_cd, ZSUNIT(dev));
732 	struct tty *tp = zst->zst_tty;
733 
734 	return (*linesw[tp->t_line].l_write)(tp, uio, flags);
735 }
736 
737 int
zsioctl(dev_t dev,u_long cmd,caddr_t data,int flag,struct proc * p)738 zsioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct proc *p)
739 {
740 	struct zstty_softc *zst = zs_device_lookup(&zstty_cd, ZSUNIT(dev));
741 	struct zs_chanstate *cs = zst->zst_cs;
742 	struct tty *tp = zst->zst_tty;
743 	int error;
744 	int s;
745 
746 	error = (*linesw[tp->t_line].l_ioctl)(tp, cmd, data, flag, p);
747 	if (error >= 0)
748 		return (error);
749 
750 	error = ttioctl(tp, cmd, data, flag, p);
751 	if (error >= 0)
752 		return (error);
753 
754 #ifdef	ZS_MD_IOCTL
755 	error = ZS_MD_IOCTL;
756 	if (error >= 0)
757 		return (error);
758 #endif	/* ZS_MD_IOCTL */
759 
760 	error = 0;
761 
762 	s = splzs();
763 
764 	switch (cmd) {
765 	case TIOCSBRK:
766 		zs_break(cs, 1);
767 		break;
768 
769 	case TIOCCBRK:
770 		zs_break(cs, 0);
771 		break;
772 
773 	case TIOCGFLAGS:
774 		*(int *)data = zst->zst_swflags;
775 		break;
776 
777 	case TIOCSFLAGS:
778 		error = suser(p);
779 		if (error)
780 			break;
781 		zst->zst_swflags = *(int *)data;
782 		if (ISSET(zst->zst_hwflags, ZS_HWFLAG_NO_DCD))
783 			SET(zst->zst_swflags, TIOCFLAG_SOFTCAR);
784 		break;
785 
786 	case TIOCSDTR:
787 		zs_modem(zst, 1);
788 		break;
789 
790 	case TIOCCDTR:
791 		zs_modem(zst, 0);
792 		break;
793 
794 	case TIOCMSET:
795 	case TIOCMBIS:
796 	case TIOCMBIC:
797 		tiocm_to_zs(zst, cmd, *(int *)data);
798 		break;
799 
800 	case TIOCMGET:
801 		*(int *)data = zs_to_tiocm(zst);
802 		break;
803 
804 	default:
805 		error = ENOTTY;
806 		break;
807 	}
808 
809 	splx(s);
810 
811 	return (error);
812 }
813 
814 /*
815  * Start or restart transmission.
816  */
817 void
zsstart(struct tty * tp)818 zsstart(struct tty *tp)
819 {
820 	struct zstty_softc *zst = zs_device_lookup(&zstty_cd, ZSUNIT(tp->t_dev));
821 	struct zs_chanstate *cs = zst->zst_cs;
822 	u_char *tba;
823 	int tbc, rr0;
824 	int s;
825 
826 	s = spltty();
827 	if (ISSET(tp->t_state, TS_BUSY | TS_TIMEOUT | TS_TTSTOP))
828 		goto out;
829 	if (zst->zst_tx_stopped)
830 		goto out;
831 
832 	ttwakeupwr(tp);
833 	if (tp->t_outq.c_cc == 0)
834 		goto out;
835 
836 	/* Grab the first contiguous region of buffer space. */
837 	tba = tp->t_outq.c_cf;
838 	tbc = ndqb(&tp->t_outq, 0);
839 
840 #if IPL_ZS != IPL_TTY
841 	(void)splzs();
842 #endif
843 
844 	zst->zst_tba = tba;
845 	zst->zst_tbc = tbc;
846 	SET(tp->t_state, TS_BUSY);
847 	zst->zst_tx_busy = 1;
848 
849 	do {
850 		rr0 = zs_read_csr(cs);
851 		if ((rr0 & ZSRR0_TX_READY) == 0)
852 			break;
853 
854 		zs_write_data(cs, *zst->zst_tba);
855 		zst->zst_tbc--;
856 		zst->zst_tba++;
857 	} while (zst->zst_tbc > 0);
858 
859 out:
860 	splx(s);
861 }
862 
863 /*
864  * Stop output, e.g., for ^S or output flush.
865  */
866 int
zsstop(struct tty * tp,int flag)867 zsstop(struct tty *tp, int flag)
868 {
869 	struct zstty_softc *zst = zs_device_lookup(&zstty_cd, ZSUNIT(tp->t_dev));
870 	int s;
871 
872 	s = splzs();
873 	if (ISSET(tp->t_state, TS_BUSY)) {
874 		/* Stop transmitting at the next chunk. */
875 		zst->zst_tbc = 0;
876 		zst->zst_heldtbc = 0;
877 		if (!ISSET(tp->t_state, TS_TTSTOP))
878 			SET(tp->t_state, TS_FLUSH);
879 	}
880 	splx(s);
881 	return 0;
882 }
883 
884 /*
885  * Set ZS tty parameters from termios.
886  * XXX - Should just copy the whole termios after
887  * making sure all the changes could be done.
888  */
889 int
zsparam(struct tty * tp,struct termios * t)890 zsparam(struct tty *tp, struct termios *t)
891 {
892 	struct zstty_softc *zst = zs_device_lookup(&zstty_cd, ZSUNIT(tp->t_dev));
893 	struct zs_chanstate *cs = zst->zst_cs;
894 	int ospeed;
895 	tcflag_t cflag;
896 	uint8_t tmp3, tmp4, tmp5;
897 	int s, error;
898 
899 	ospeed = t->c_ospeed;
900 	cflag = t->c_cflag;
901 
902 	/* Check requested parameters. */
903 	if (ospeed < 0)
904 		return (EINVAL);
905 	if (t->c_ispeed && t->c_ispeed != ospeed)
906 		return (EINVAL);
907 
908 	/*
909 	 * For the console, always force CLOCAL and !HUPCL, so that the port
910 	 * is always active.
911 	 */
912 	if (ISSET(zst->zst_swflags, TIOCFLAG_SOFTCAR) ||
913 	    ISSET(zst->zst_hwflags, ZS_HWFLAG_CONSOLE)) {
914 		SET(cflag, CLOCAL);
915 		CLR(cflag, HUPCL);
916 	}
917 
918 	/*
919 	 * Only whack the UART when params change.
920 	 * Some callers need to clear tp->t_ospeed
921 	 * to make sure initialization gets done.
922 	 */
923 	if (tp->t_ospeed == ospeed &&
924 	    tp->t_cflag == cflag)
925 		return (0);
926 
927 	/*
928 	 * Call MD functions to deal with changed
929 	 * clock modes or H/W flow control modes.
930 	 * The BRG divisor is set now. (reg 12,13)
931 	 */
932 	error = zs_set_speed(cs, ospeed);
933 	if (error)
934 		return (error);
935 	error = zs_set_modes(cs, cflag);
936 	if (error)
937 		return (error);
938 
939 	/*
940 	 * Block interrupts so that state will not
941 	 * be altered until we are done setting it up.
942 	 *
943 	 * Initial values in cs_preg are set before
944 	 * our attach routine is called.  The master
945 	 * interrupt enable is handled by zsc.c
946 	 *
947 	 */
948 	s = splzs();
949 
950 	/*
951 	 * Recalculate which status ints to enable.
952 	 */
953 	zs_maskintr(zst);
954 
955 	/* Recompute character size bits. */
956 	tmp3 = cs->cs_preg[3];
957 	tmp5 = cs->cs_preg[5];
958 	CLR(tmp3, ZSWR3_RXSIZE);
959 	CLR(tmp5, ZSWR5_TXSIZE);
960 	switch (ISSET(cflag, CSIZE)) {
961 	case CS5:
962 		SET(tmp3, ZSWR3_RX_5);
963 		SET(tmp5, ZSWR5_TX_5);
964 		break;
965 	case CS6:
966 		SET(tmp3, ZSWR3_RX_6);
967 		SET(tmp5, ZSWR5_TX_6);
968 		break;
969 	case CS7:
970 		SET(tmp3, ZSWR3_RX_7);
971 		SET(tmp5, ZSWR5_TX_7);
972 		break;
973 	case CS8:
974 		SET(tmp3, ZSWR3_RX_8);
975 		SET(tmp5, ZSWR5_TX_8);
976 		break;
977 	}
978 	cs->cs_preg[3] = tmp3;
979 	cs->cs_preg[5] = tmp5;
980 
981 	/*
982 	 * Recompute the stop bits and parity bits.  Note that
983 	 * zs_set_speed() may have set clock selection bits etc.
984 	 * in wr4, so those must preserved.
985 	 */
986 	tmp4 = cs->cs_preg[4];
987 	CLR(tmp4, ZSWR4_SBMASK | ZSWR4_PARMASK);
988 	if (ISSET(cflag, CSTOPB))
989 		SET(tmp4, ZSWR4_TWOSB);
990 	else
991 		SET(tmp4, ZSWR4_ONESB);
992 	if (!ISSET(cflag, PARODD))
993 		SET(tmp4, ZSWR4_EVENP);
994 	if (ISSET(cflag, PARENB))
995 		SET(tmp4, ZSWR4_PARENB);
996 	cs->cs_preg[4] = tmp4;
997 
998 	/* And copy to tty. */
999 	tp->t_ispeed = 0;
1000 	tp->t_ospeed = ospeed;
1001 	tp->t_cflag = cflag;
1002 
1003 	/*
1004 	 * If nothing is being transmitted, set up new current values,
1005 	 * else mark them as pending.
1006 	 */
1007 	if (!cs->cs_heldchange) {
1008 		if (zst->zst_tx_busy) {
1009 			zst->zst_heldtbc = zst->zst_tbc;
1010 			zst->zst_tbc = 0;
1011 			cs->cs_heldchange = 1;
1012 		} else
1013 			zs_loadchannelregs(cs);
1014 	}
1015 
1016 	/*
1017 	 * If hardware flow control is disabled, turn off the buffer water
1018 	 * marks and unblock any soft flow control state.  Otherwise, enable
1019 	 * the water marks.
1020 	 */
1021 	if (!ISSET(cflag, CHWFLOW)) {
1022 		zst->zst_r_hiwat = 0;
1023 		zst->zst_r_lowat = 0;
1024 		if (ISSET(zst->zst_rx_flags, RX_TTY_OVERFLOWED)) {
1025 			CLR(zst->zst_rx_flags, RX_TTY_OVERFLOWED);
1026 			zst->zst_rx_ready = 1;
1027 			cs->cs_softreq = 1;
1028 		}
1029 		if (ISSET(zst->zst_rx_flags, RX_TTY_BLOCKED|RX_IBUF_BLOCKED)) {
1030 			CLR(zst->zst_rx_flags, RX_TTY_BLOCKED|RX_IBUF_BLOCKED);
1031 			zs_hwiflow(zst);
1032 		}
1033 	} else {
1034 		zst->zst_r_hiwat = zstty_rbuf_hiwat;
1035 		zst->zst_r_lowat = zstty_rbuf_lowat;
1036 	}
1037 
1038 	/*
1039 	 * Force a recheck of the hardware carrier and flow control status,
1040 	 * since we may have changed which bits we're looking at.
1041 	 */
1042 	zstty_stint(cs, 1);
1043 
1044 	splx(s);
1045 
1046 	/*
1047 	 * If hardware flow control is disabled, unblock any hard flow control
1048 	 * state.
1049 	 */
1050 	if (!ISSET(cflag, CHWFLOW)) {
1051 		if (zst->zst_tx_stopped) {
1052 			zst->zst_tx_stopped = 0;
1053 			zsstart(tp);
1054 		}
1055 	}
1056 
1057 	zstty_softint(cs);
1058 
1059 	return (0);
1060 }
1061 
1062 /*
1063  * Compute interrupt enable bits and set in the pending bits. Called both
1064  * in zsparam() and when PPS (pulse per second timing) state changes.
1065  * Must be called at splzs().
1066  */
1067 void
zs_maskintr(struct zstty_softc * zst)1068 zs_maskintr(struct zstty_softc *zst)
1069 {
1070 	struct zs_chanstate *cs = zst->zst_cs;
1071 	uint8_t tmp15;
1072 
1073 	cs->cs_rr0_mask = cs->cs_rr0_cts | cs->cs_rr0_dcd;
1074 	if (zst->zst_ppsmask != 0)
1075 		cs->cs_rr0_mask |= cs->cs_rr0_pps;
1076 	tmp15 = cs->cs_preg[15];
1077 	if (ISSET(cs->cs_rr0_mask, ZSRR0_DCD))
1078 		SET(tmp15, ZSWR15_DCD_IE);
1079 	else
1080 		CLR(tmp15, ZSWR15_DCD_IE);
1081 	if (ISSET(cs->cs_rr0_mask, ZSRR0_CTS))
1082 		SET(tmp15, ZSWR15_CTS_IE);
1083 	else
1084 		CLR(tmp15, ZSWR15_CTS_IE);
1085 	cs->cs_preg[15] = tmp15;
1086 }
1087 
1088 
1089 /*
1090  * Raise or lower modem control (DTR/RTS) signals.  If a character is
1091  * in transmission, the change is deferred.
1092  * Called at splzs().
1093  */
1094 void
zs_modem(struct zstty_softc * zst,int onoff)1095 zs_modem(struct zstty_softc *zst, int onoff)
1096 {
1097 	struct zs_chanstate *cs = zst->zst_cs, *ccs;
1098 
1099 	if (cs->cs_wr5_dtr == 0)
1100 		return;
1101 
1102 	ccs = (cs->cs_ctl_chan != NULL ? cs->cs_ctl_chan : cs);
1103 
1104 	if (onoff)
1105 		SET(ccs->cs_preg[5], cs->cs_wr5_dtr);
1106 	else
1107 		CLR(ccs->cs_preg[5], cs->cs_wr5_dtr);
1108 
1109 	if (!cs->cs_heldchange) {
1110 		if (zst->zst_tx_busy) {
1111 			zst->zst_heldtbc = zst->zst_tbc;
1112 			zst->zst_tbc = 0;
1113 			cs->cs_heldchange = 1;
1114 		} else
1115 			zs_loadchannelregs(cs);
1116 	}
1117 }
1118 
1119 /*
1120  * Set modem bits.
1121  * Called at splzs().
1122  */
1123 void
tiocm_to_zs(struct zstty_softc * zst,u_long how,int ttybits)1124 tiocm_to_zs(struct zstty_softc *zst, u_long how, int ttybits)
1125 {
1126 	struct zs_chanstate *cs = zst->zst_cs, *ccs;
1127 	uint8_t zsbits;
1128 
1129 	ccs = (cs->cs_ctl_chan != NULL ? cs->cs_ctl_chan : cs);
1130 
1131 	zsbits = 0;
1132 	if (ISSET(ttybits, TIOCM_DTR))
1133 		SET(zsbits, ZSWR5_DTR);
1134 	if (ISSET(ttybits, TIOCM_RTS))
1135 		SET(zsbits, ZSWR5_RTS);
1136 
1137 	switch (how) {
1138 	case TIOCMBIC:
1139 		CLR(ccs->cs_preg[5], zsbits);
1140 		break;
1141 
1142 	case TIOCMBIS:
1143 		SET(ccs->cs_preg[5], zsbits);
1144 		break;
1145 
1146 	case TIOCMSET:
1147 		CLR(ccs->cs_preg[5], ZSWR5_RTS | ZSWR5_DTR);
1148 		SET(ccs->cs_preg[5], zsbits);
1149 		break;
1150 	}
1151 
1152 	if (!cs->cs_heldchange) {
1153 		if (zst->zst_tx_busy) {
1154 			zst->zst_heldtbc = zst->zst_tbc;
1155 			zst->zst_tbc = 0;
1156 			cs->cs_heldchange = 1;
1157 		} else
1158 			zs_loadchannelregs(cs);
1159 	}
1160 }
1161 
1162 /*
1163  * Get modem bits.
1164  * Called at splzs().
1165  */
1166 int
zs_to_tiocm(struct zstty_softc * zst)1167 zs_to_tiocm(struct zstty_softc *zst)
1168 {
1169 	struct zs_chanstate *cs = zst->zst_cs, *ccs;
1170 	uint8_t zsbits;
1171 	int ttybits = 0;
1172 
1173 	ccs = (cs->cs_ctl_chan != NULL ? cs->cs_ctl_chan : cs);
1174 
1175 	zsbits = ccs->cs_preg[5];
1176 	if (ISSET(zsbits, ZSWR5_DTR))
1177 		SET(ttybits, TIOCM_DTR);
1178 	if (ISSET(zsbits, ZSWR5_RTS))
1179 		SET(ttybits, TIOCM_RTS);
1180 
1181 	zsbits = cs->cs_rr0;
1182 	if (ISSET(zsbits, ZSRR0_DCD))
1183 		SET(ttybits, TIOCM_CD);
1184 	if (ISSET(zsbits, ZSRR0_CTS))
1185 		SET(ttybits, TIOCM_CTS);
1186 
1187 	return (ttybits);
1188 }
1189 
1190 /*
1191  * Try to block or unblock input using hardware flow-control.
1192  * This is called by kern/tty.c if MDMBUF|CRTSCTS is set, and
1193  * if this function returns non-zero, the TS_TBLOCK flag will
1194  * be set or cleared according to the "block" arg passed.
1195  */
1196 int
zshwiflow(struct tty * tp,int block)1197 zshwiflow(struct tty *tp, int block)
1198 {
1199 	struct zstty_softc *zst = zs_device_lookup(&zstty_cd, ZSUNIT(tp->t_dev));
1200 	struct zs_chanstate *cs = zst->zst_cs;
1201 	int s;
1202 
1203 	if (cs->cs_wr5_rts == 0)
1204 		return (0);
1205 
1206 	s = splzs();
1207 	if (block) {
1208 		if (!ISSET(zst->zst_rx_flags, RX_TTY_BLOCKED)) {
1209 			SET(zst->zst_rx_flags, RX_TTY_BLOCKED);
1210 			zs_hwiflow(zst);
1211 		}
1212 	} else {
1213 		if (ISSET(zst->zst_rx_flags, RX_TTY_OVERFLOWED)) {
1214 			CLR(zst->zst_rx_flags, RX_TTY_OVERFLOWED);
1215 			zst->zst_rx_ready = 1;
1216 			cs->cs_softreq = 1;
1217 		}
1218 		if (ISSET(zst->zst_rx_flags, RX_TTY_BLOCKED)) {
1219 			CLR(zst->zst_rx_flags, RX_TTY_BLOCKED);
1220 			zs_hwiflow(zst);
1221 		}
1222 	}
1223 	splx(s);
1224 	return (1);
1225 }
1226 
1227 /*
1228  * Internal version of zshwiflow
1229  * Called at splzs()
1230  */
1231 void
zs_hwiflow(struct zstty_softc * zst)1232 zs_hwiflow(struct zstty_softc *zst)
1233 {
1234 	struct zs_chanstate *cs = zst->zst_cs, *ccs;
1235 
1236 	if (cs->cs_wr5_rts == 0)
1237 		return;
1238 
1239 	ccs = (cs->cs_ctl_chan != NULL ? cs->cs_ctl_chan : cs);
1240 
1241 	if (ISSET(zst->zst_rx_flags, RX_ANY_BLOCK)) {
1242 		CLR(ccs->cs_preg[5], cs->cs_wr5_rts);
1243 		CLR(ccs->cs_creg[5], cs->cs_wr5_rts);
1244 	} else {
1245 		SET(ccs->cs_preg[5], cs->cs_wr5_rts);
1246 		SET(ccs->cs_creg[5], cs->cs_wr5_rts);
1247 	}
1248 	zs_write_reg(ccs, 5, ccs->cs_creg[5]);
1249 }
1250 
1251 
1252 /****************************************************************
1253  * Interface to the lower layer (zscc)
1254  ****************************************************************/
1255 
1256 void zstty_rxsoft(struct zstty_softc *, struct tty *);
1257 void zstty_txsoft(struct zstty_softc *, struct tty *);
1258 void zstty_stsoft(struct zstty_softc *, struct tty *);
1259 void zstty_diag(void *);
1260 
1261 /*
1262  * Receiver Ready interrupt.
1263  * Called at splzs().
1264  */
1265 void
zstty_rxint(struct zs_chanstate * cs)1266 zstty_rxint(struct zs_chanstate *cs)
1267 {
1268 	struct zstty_softc *zst = cs->cs_private;
1269 	uint8_t *put, *end;
1270 	u_int cc;
1271 	uint8_t rr0, rr1, c;
1272 
1273 	end = zst->zst_ebuf;
1274 	put = zst->zst_rbput;
1275 	cc = zst->zst_rbavail;
1276 
1277 	while (cc > 0) {
1278 		/*
1279 		 * First read the status, because reading the received char
1280 		 * destroys the status of this char.
1281 		 */
1282 		rr1 = zs_read_reg(cs, 1);
1283 		c = zs_read_data(cs);
1284 
1285 		if (ISSET(rr1, ZSRR1_FE | ZSRR1_DO | ZSRR1_PE)) {
1286 			/* Clear the receive error. */
1287 			zs_write_csr(cs, ZSWR0_RESET_ERRORS);
1288 		}
1289 
1290 		put[0] = c;
1291 		put[1] = rr1;
1292 		put += 2;
1293 		if (put >= end)
1294 			put = zst->zst_rbuf;
1295 		cc--;
1296 
1297 		rr0 = zs_read_csr(cs);
1298 		if (!ISSET(rr0, ZSRR0_RX_READY))
1299 			break;
1300 	}
1301 
1302 	/*
1303 	 * Current string of incoming characters ended because
1304 	 * no more data was available or we ran out of space.
1305 	 * Schedule a receive event if any data was received.
1306 	 * If we're out of space, turn off receive interrupts.
1307 	 */
1308 	zst->zst_rbput = put;
1309 	zst->zst_rbavail = cc;
1310 	if (!ISSET(zst->zst_rx_flags, RX_TTY_OVERFLOWED)) {
1311 		zst->zst_rx_ready = 1;
1312 		cs->cs_softreq = 1;
1313 	}
1314 
1315 	/*
1316 	 * See if we are in danger of overflowing a buffer. If
1317 	 * so, use hardware flow control to ease the pressure.
1318 	 */
1319 	if (!ISSET(zst->zst_rx_flags, RX_IBUF_BLOCKED) &&
1320 	    cc < zst->zst_r_hiwat) {
1321 		SET(zst->zst_rx_flags, RX_IBUF_BLOCKED);
1322 		zs_hwiflow(zst);
1323 	}
1324 
1325 	/*
1326 	 * If we're out of space, disable receive interrupts
1327 	 * until the queue has drained a bit.
1328 	 */
1329 	if (!cc) {
1330 		SET(zst->zst_rx_flags, RX_IBUF_OVERFLOWED);
1331 		CLR(cs->cs_preg[1], ZSWR1_RIE);
1332 		cs->cs_creg[1] = cs->cs_preg[1];
1333 		zs_write_reg(cs, 1, cs->cs_creg[1]);
1334 	}
1335 }
1336 
1337 /*
1338  * Transmitter Ready interrupt.
1339  * Called at splzs().
1340  */
1341 void
zstty_txint(struct zs_chanstate * cs)1342 zstty_txint(struct zs_chanstate *cs)
1343 {
1344 	struct zstty_softc *zst = cs->cs_private;
1345 	int rr0;
1346 
1347 	zs_write_csr(cs, ZSWR0_RESET_TXINT);
1348 
1349 	/*
1350 	 * If we've delayed a parameter change, do it now, and restart
1351 	 * output.
1352 	 */
1353 	if (cs->cs_heldchange) {
1354 		zs_loadchannelregs(cs);
1355 		cs->cs_heldchange = 0;
1356 		zst->zst_tbc = zst->zst_heldtbc;
1357 		zst->zst_heldtbc = 0;
1358 	}
1359 
1360 	while (zst->zst_tbc > 0) {
1361 		rr0 = zs_read_csr(cs);
1362 		if ((rr0 & ZSRR0_TX_READY) == 0)
1363 			break;
1364 
1365 		zs_write_data(cs, *zst->zst_tba);
1366 		zst->zst_tbc--;
1367 		zst->zst_tba++;
1368 	}
1369 
1370 	if (zst->zst_tbc == 0) {
1371 		if (zst->zst_tx_busy) {
1372 			zst->zst_tx_busy = 0;
1373 			zst->zst_tx_done = 1;
1374 			cs->cs_softreq = 1;
1375 		}
1376 	}
1377 }
1378 
1379 #ifdef DDB
1380 #include <ddb/db_var.h>
1381 #define	DB_CONSOLE	db_console
1382 #else
1383 #define	DB_CONSOLE	0
1384 #endif
1385 
1386 /*
1387  * Status Change interrupt.
1388  * Called at splzs().
1389  */
1390 void
zstty_stint(struct zs_chanstate * cs,int force)1391 zstty_stint(struct zs_chanstate *cs, int force)
1392 {
1393 	struct zstty_softc *zst = cs->cs_private;
1394 	struct tty *tp = zst->zst_tty;
1395 	uint8_t rr0, delta;
1396 
1397 	rr0 = zs_read_csr(cs);
1398 	zs_write_csr(cs, ZSWR0_RESET_STATUS);
1399 
1400 	/*
1401 	 * Check here for console break, so that we can abort
1402 	 * even when interrupts are locking up the machine.
1403 	 */
1404 	if ((zst->zst_hwflags & ZS_HWFLAG_CONSOLE_INPUT) &&
1405 	    ISSET(rr0, ZSRR0_BREAK) && DB_CONSOLE)
1406 		zs_abort(cs);
1407 
1408 	if (!force)
1409 		delta = rr0 ^ cs->cs_rr0;
1410 	else
1411 		delta = cs->cs_rr0_mask;
1412 
1413 	ttytstamp(tp, cs->cs_rr0 & ZSRR0_CTS, rr0 & ZSRR0_CTS,
1414 	    cs->cs_rr0 & ZSRR0_DCD, rr0 & ZSRR0_DCD);
1415 
1416 	cs->cs_rr0 = rr0;
1417 
1418 	if (ISSET(delta, cs->cs_rr0_mask)) {
1419 		SET(cs->cs_rr0_delta, delta);
1420 
1421 		/*
1422 		 * Stop output immediately if we lose the output
1423 		 * flow control signal or carrier detect.
1424 		 */
1425 		if (ISSET(~rr0, cs->cs_rr0_mask)) {
1426 			zst->zst_tbc = 0;
1427 			zst->zst_heldtbc = 0;
1428 		}
1429 
1430 		zst->zst_st_check = 1;
1431 		cs->cs_softreq = 1;
1432 	}
1433 }
1434 
1435 void
zstty_diag(void * arg)1436 zstty_diag(void *arg)
1437 {
1438 	struct zstty_softc *zst = arg;
1439 	int overflows, floods;
1440 	int s;
1441 
1442 	s = splzs();
1443 	overflows = zst->zst_overflows;
1444 	zst->zst_overflows = 0;
1445 	floods = zst->zst_floods;
1446 	zst->zst_floods = 0;
1447 	zst->zst_errors = 0;
1448 	splx(s);
1449 
1450 	log(LOG_WARNING, "%s: %d silo overflow%s, %d ibuf flood%s\n",
1451 	    zst->zst_dev.dv_xname,
1452 	    overflows, overflows == 1 ? "" : "s",
1453 	    floods, floods == 1 ? "" : "s");
1454 }
1455 
1456 void
zstty_rxsoft(struct zstty_softc * zst,struct tty * tp)1457 zstty_rxsoft(struct zstty_softc *zst, struct tty *tp)
1458 {
1459 	struct zs_chanstate *cs = zst->zst_cs;
1460 	int (*rint)(int, struct tty *) = linesw[tp->t_line].l_rint;
1461 	uint8_t *get, *end;
1462 	u_int cc, scc;
1463 	uint8_t rr1;
1464 	int code;
1465 	int s;
1466 
1467 	end = zst->zst_ebuf;
1468 	get = zst->zst_rbget;
1469 	scc = cc = zstty_rbuf_size - zst->zst_rbavail;
1470 
1471 	if (cc == zstty_rbuf_size) {
1472 		zst->zst_floods++;
1473 		if (zst->zst_errors++ == 0)
1474 			timeout_add_sec(&zst->zst_diag_ch, 60);
1475 	}
1476 
1477 	/* If not yet open, drop the entire buffer content here */
1478 	if (!ISSET(tp->t_state, TS_ISOPEN)) {
1479 		get += cc << 1;
1480 		if (get >= end)
1481 			get -= zstty_rbuf_size << 1;
1482 		cc = 0;
1483 	}
1484 	while (cc) {
1485 		code = get[0];
1486 		rr1 = get[1];
1487 		if (ISSET(rr1, ZSRR1_DO | ZSRR1_FE | ZSRR1_PE)) {
1488 			if (ISSET(rr1, ZSRR1_DO)) {
1489 				zst->zst_overflows++;
1490 				if (zst->zst_errors++ == 0)
1491 					timeout_add_sec(&zst->zst_diag_ch, 60);
1492 			}
1493 			if (ISSET(rr1, ZSRR1_FE))
1494 				SET(code, TTY_FE);
1495 			if (ISSET(rr1, ZSRR1_PE))
1496 				SET(code, TTY_PE);
1497 		}
1498 		if ((*rint)(code, tp) == -1) {
1499 			/*
1500 			 * The line discipline's buffer is out of space.
1501 			 */
1502 			if (!ISSET(zst->zst_rx_flags, RX_TTY_BLOCKED)) {
1503 				/*
1504 				 * We're either not using flow control, or the
1505 				 * line discipline didn't tell us to block for
1506 				 * some reason.  Either way, we have no way to
1507 				 * know when there's more space available, so
1508 				 * just drop the rest of the data.
1509 				 */
1510 				get += cc << 1;
1511 				if (get >= end)
1512 					get -= zstty_rbuf_size << 1;
1513 				cc = 0;
1514 			} else {
1515 				/*
1516 				 * Don't schedule any more receive processing
1517 				 * until the line discipline tells us there's
1518 				 * space available (through comhwiflow()).
1519 				 * Leave the rest of the data in the input
1520 				 * buffer.
1521 				 */
1522 				SET(zst->zst_rx_flags, RX_TTY_OVERFLOWED);
1523 			}
1524 			break;
1525 		}
1526 		get += 2;
1527 		if (get >= end)
1528 			get = zst->zst_rbuf;
1529 		cc--;
1530 	}
1531 
1532 	if (cc != scc) {
1533 		zst->zst_rbget = get;
1534 		s = splzs();
1535 		cc = zst->zst_rbavail += scc - cc;
1536 		/* Buffers should be ok again, release possible block. */
1537 		if (cc >= zst->zst_r_lowat) {
1538 			if (ISSET(zst->zst_rx_flags, RX_IBUF_OVERFLOWED)) {
1539 				CLR(zst->zst_rx_flags, RX_IBUF_OVERFLOWED);
1540 				SET(cs->cs_preg[1], ZSWR1_RIE);
1541 				cs->cs_creg[1] = cs->cs_preg[1];
1542 				zs_write_reg(cs, 1, cs->cs_creg[1]);
1543 			}
1544 			if (ISSET(zst->zst_rx_flags, RX_IBUF_BLOCKED)) {
1545 				CLR(zst->zst_rx_flags, RX_IBUF_BLOCKED);
1546 				zs_hwiflow(zst);
1547 			}
1548 		}
1549 		splx(s);
1550 	}
1551 }
1552 
1553 void
zstty_txsoft(struct zstty_softc * zst,struct tty * tp)1554 zstty_txsoft(struct zstty_softc *zst, struct tty *tp)
1555 {
1556 	int s;
1557 
1558 	CLR(tp->t_state, TS_BUSY);
1559 	if (ISSET(tp->t_state, TS_FLUSH))
1560 		CLR(tp->t_state, TS_FLUSH);
1561 	else {
1562 		s = splzs();
1563 		ndflush(&tp->t_outq, (int)(zst->zst_tba - tp->t_outq.c_cf));
1564 		splx(s);
1565 	}
1566 	(*linesw[tp->t_line].l_start)(tp);
1567 }
1568 
1569 void
zstty_stsoft(struct zstty_softc * zst,struct tty * tp)1570 zstty_stsoft(struct zstty_softc *zst, struct tty *tp)
1571 {
1572 	struct zs_chanstate *cs = zst->zst_cs;
1573 	uint8_t rr0, delta;
1574 	int s;
1575 
1576 	s = splzs();
1577 	rr0 = cs->cs_rr0;
1578 	delta = cs->cs_rr0_delta;
1579 	cs->cs_rr0_delta = 0;
1580 	splx(s);
1581 
1582 	if (ISSET(delta, cs->cs_rr0_dcd)) {
1583 		/*
1584 		 * Inform the tty layer that carrier detect changed.
1585 		 */
1586 		(void)(*linesw[tp->t_line].l_modem)(tp, ISSET(rr0, ZSRR0_DCD));
1587 	}
1588 
1589 	if (ISSET(delta, cs->cs_rr0_cts)) {
1590 		/* Block or unblock output according to flow control. */
1591 		if (ISSET(rr0, cs->cs_rr0_cts)) {
1592 			zst->zst_tx_stopped = 0;
1593 			(*linesw[tp->t_line].l_start)(tp);
1594 		} else {
1595 			zst->zst_tx_stopped = 1;
1596 		}
1597 	}
1598 }
1599 
1600 /*
1601  * Software interrupt.  Called at zssoft
1602  *
1603  * The main job to be done here is to empty the input ring
1604  * by passing its contents up to the tty layer.  The ring is
1605  * always emptied during this operation, therefore the ring
1606  * must not be larger than the space after "high water" in
1607  * the tty layer, or the tty layer might drop our input.
1608  *
1609  * Note: an "input blockage" condition is assumed to exist if
1610  * EITHER the TS_TBLOCK flag or zst_rx_blocked flag is set.
1611  */
1612 void
zstty_softint(struct zs_chanstate * cs)1613 zstty_softint(struct zs_chanstate *cs)
1614 {
1615 	struct zstty_softc *zst = cs->cs_private;
1616 	struct tty *tp = zst->zst_tty;
1617 	int s;
1618 
1619 	s = spltty();
1620 
1621 	if (zst->zst_rx_ready) {
1622 		zst->zst_rx_ready = 0;
1623 		zstty_rxsoft(zst, tp);
1624 	}
1625 
1626 	if (zst->zst_st_check) {
1627 		zst->zst_st_check = 0;
1628 		zstty_stsoft(zst, tp);
1629 	}
1630 
1631 	if (zst->zst_tx_done) {
1632 		zst->zst_tx_done = 0;
1633 		zstty_txsoft(zst, tp);
1634 	}
1635 
1636 	splx(s);
1637 }
1638 
1639 struct zsops zsops_tty = {
1640 	zstty_rxint,	/* receive char available */
1641 	zstty_stint,	/* external/status */
1642 	zstty_txint,	/* xmit buffer empty */
1643 	zstty_softint,	/* process software interrupt */
1644 };
1645