xref: /netbsd-src/sys/arch/arm/clps711x/clpscom.c (revision bdc22b2e01993381dcefeff2bc9b56ca75a4235c)
1 /*      $NetBSD: clpscom.c,v 1.6 2015/04/13 21:18:41 riastradh Exp $      */
2 /*
3  * Copyright (c) 2013 KIYOHARA Takashi
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
17  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
18  * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
19  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
20  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
21  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
23  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
24  * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
25  * POSSIBILITY OF SUCH DAMAGE.
26  */
27 #include <sys/cdefs.h>
28 __KERNEL_RCSID(0, "$NetBSD: clpscom.c,v 1.6 2015/04/13 21:18:41 riastradh Exp $");
29 
30 #include "rnd.h"
31 
32 #include <sys/param.h>
33 #include <sys/bus.h>
34 #include <sys/conf.h>
35 #include <sys/device.h>
36 #include <sys/errno.h>
37 #include <sys/fcntl.h>
38 #include <sys/intr.h>
39 #include <sys/kauth.h>
40 #include <sys/lwp.h>
41 #include <sys/malloc.h>
42 #include <sys/systm.h>
43 #include <sys/termios.h>
44 #include <sys/tty.h>
45 #include <sys/types.h>
46 
47 #include <arm/clps711x/clps711xreg.h>
48 #include <arm/clps711x/clpssocvar.h>
49 
50 #include <dev/cons.h>
51 
52 #ifdef RND_COM
53 #include <sys/rndsource.h>
54 #endif
55 
56 #include "ioconf.h"
57 #include "locators.h"
58 
59 #define COMUNIT(x)	TTUNIT(x)
60 #define COMDIALOUT(x)	TTDIALOUT(x)
61 
62 #define CLPSCOM_RING_SIZE	2048
63 #define UART_FIFO_SIZE		16
64 
65 #define CLPSCOM_READ_CON(sc) \
66 	bus_space_read_4((sc)->sc_iot, (sc)->sc_ioh, PS711X_SYSCON)
67 #define CLPSCOM_WRITE_CON(sc, val) \
68 	bus_space_write_4((sc)->sc_iot, (sc)->sc_ioh, PS711X_SYSCON, (val))
69 #define CLPSCOM_READ_FLG(sc) \
70 	bus_space_read_4((sc)->sc_iot, (sc)->sc_ioh, PS711X_SYSFLG)
71 #define CLPSCOM_WRITE_FLG(sc, val) \
72 	bus_space_write_4((sc)->sc_iot, (sc)->sc_ioh, PS711X_SYSFLG, (val))
73 #define CLPSCOM_READ(sc) \
74 	bus_space_read_4((sc)->sc_iot, (sc)->sc_ioh, PS711X_UARTDR)
75 #define CLPSCOM_WRITE(sc, val) \
76 	bus_space_write_1((sc)->sc_iot, (sc)->sc_ioh, PS711X_UARTDR, (val))
77 #define CLPSCOM_WRITE_MULTI(sc, val, n) \
78   bus_space_write_multi_1((sc)->sc_iot, (sc)->sc_ioh, PS711X_UARTDR, (val), (n))
79 #define CLPSCOM_READ_UBRLCR(sc) \
80 	bus_space_read_4((sc)->sc_iot, (sc)->sc_ioh, PS711X_UBRLCR)
81 #define CLPSCOM_WRITE_UBRLCR(sc, val) \
82 	bus_space_write_4((sc)->sc_iot, (sc)->sc_ioh, PS711X_UBRLCR, (val))
83 
84 struct clpscom_softc {
85 	device_t sc_dev;
86 	bus_space_tag_t sc_iot;
87 	bus_space_handle_t sc_ioh;
88 	int sc_irq[3];
89 	void *sc_ih[3];
90 #define CLPSCOM_TXINT	0
91 #define CLPSCOM_RXINT	1
92 #define CLPSCOM_MSINT	2
93 
94 	void *sc_si;
95 
96 	struct tty *sc_tty;
97 
98 	u_char *sc_tba;
99 	u_int sc_tbc;
100 	u_char *sc_rbuf;
101 	char *volatile sc_rbget;
102 	char *volatile sc_rbput;
103 	volatile int sc_rbavail;
104 
105 #define CLPSCOM_MODEM_STATUS_MASK (SYSFLG_DCD | SYSFLG_DSR | SYSFLG_CTS)
106 	uint32_t sc_ms;
107 	uint32_t sc_ms_dcd;
108 	uint32_t sc_ms_cts;
109 	uint32_t sc_ms_mask;
110 	uint32_t sc_ms_delta;
111 
112 	int sc_tx_stopped;
113 
114 	int sc_tx_done;
115 	int sc_rx_ready;
116 	int sc_ms_changed;
117 
118 	int sc_hwflags;
119 #define COM_HW_CONSOLE	(1 << 0)
120 #define COM_HW_DEV_OK	(1 << 1)
121 #define COM_HW_KGDB	(1 << 2)
122 	int sc_swflags;
123 
124 #ifdef RND_COM
125 	krandsource_t rnd_source;
126 #endif
127 };
128 
129 static int clpscom_match(device_t, cfdata_t, void *);
130 static void clpscom_attach(device_t, device_t, void *);
131 
132 static int clpscom_txintr(void *);
133 static int clpscom_rxintr(void *);
134 static int clpscom_msintr(void *);
135 static void clpscom_soft(void *);
136 
137 static void clpscom_start(struct tty *);
138 static int clpscom_param(struct tty *, struct termios *);
139 static int clpscom_hwiflow(struct tty *, int);
140 
141 dev_type_open(clpscomopen);
142 dev_type_close(clpscomclose);
143 dev_type_read(clpscomread);
144 dev_type_write(clpscomwrite);
145 dev_type_ioctl(clpscomioctl);
146 dev_type_stop(clpscomstop);
147 dev_type_tty(clpscomtty);
148 dev_type_poll(clpscompoll);
149 
150 static void clpscom_iflush(struct clpscom_softc *);
151 static void clpscom_shutdown(struct clpscom_softc *);
152 static void clpscom_break(struct clpscom_softc *, int);
153 static int clpscom_to_tiocm(struct clpscom_softc *);
154 
155 static void clpscom_rxsoft(struct clpscom_softc *, struct tty *);
156 static void clpscom_mssoft(struct clpscom_softc *, struct tty *);
157 
158 static inline uint32_t clpscom_rate2ubrlcr(int);
159 static uint32_t clpscom_cflag2ubrlcr(tcflag_t);
160 
161 static int clpscom_cngetc(dev_t);
162 static void clpscom_cnputc(dev_t, int);
163 static void clpscom_cnpollc(dev_t, int);
164 
165 CFATTACH_DECL_NEW(clpscom, sizeof(struct clpscom_softc),
166     clpscom_match, clpscom_attach, NULL, NULL);
167 
168 const struct cdevsw clpscom_cdevsw = {
169 	.d_open = clpscomopen,
170 	.d_close = clpscomclose,
171 	.d_read = clpscomread,
172 	.d_write = clpscomwrite,
173 	.d_ioctl = clpscomioctl,
174 	.d_stop = clpscomstop,
175 	.d_tty = clpscomtty,
176 	.d_poll = clpscompoll,
177 	.d_mmap = nommap,
178 	.d_kqfilter = ttykqfilter,
179 	.d_discard = nodiscard,
180 	.d_flag = D_TTY
181 };
182 
183 static struct cnm_state clpscom_cnm_state;
184 static vaddr_t clpscom_cnaddr = 0;
185 static int clpscom_cnrate;
186 static tcflag_t clpscom_cncflag;
187 
188 
189 /* ARGSUSED */
190 static int
191 clpscom_match(device_t parent, cfdata_t match, void *aux)
192 {
193 
194 	return 1;
195 }
196 
197 /* ARGSUSED */
198 static void
199 clpscom_attach(device_t parent, device_t self, void *aux)
200 {
201 	struct clpscom_softc *sc = device_private(self);
202 	struct clpssoc_attach_args *aa = aux;
203 	int i;
204 
205 	aprint_naive("\n");
206 	aprint_normal("\n");
207 
208 	sc->sc_dev = self;
209 	sc->sc_iot = aa->aa_iot;
210 	sc->sc_ioh = *aa->aa_ioh;
211 	for (i = 0; i < __arraycount(aa->aa_irq); i++) {
212 		sc->sc_irq[i] = aa->aa_irq[i];
213 		sc->sc_ih[i] = NULL;
214 	}
215 
216 	if (clpscom_cnaddr != 0)
217 		SET(sc->sc_hwflags, COM_HW_CONSOLE);
218 
219 	sc->sc_tty = tty_alloc();
220 	sc->sc_tty->t_oproc = clpscom_start;
221 	sc->sc_tty->t_param = clpscom_param;
222 	sc->sc_tty->t_hwiflow = clpscom_hwiflow;
223 
224 	sc->sc_tbc = 0;
225 	sc->sc_rbuf = malloc(CLPSCOM_RING_SIZE << 1, M_DEVBUF, M_NOWAIT);
226 	if (sc->sc_rbuf == NULL) {
227 		aprint_error_dev(self, "unable to allocate ring buffer\n");
228 		return;
229 	}
230 	sc->sc_rbput = sc->sc_rbget = sc->sc_rbuf;
231 	sc->sc_rbavail = CLPSCOM_RING_SIZE;
232 
233 	tty_attach(sc->sc_tty);
234 
235 	if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
236 		int maj = cdevsw_lookup_major(&clpscom_cdevsw);
237 
238 		sc->sc_tty->t_dev = makedev(maj, device_unit(sc->sc_dev));
239 		cn_tab->cn_dev = sc->sc_tty->t_dev;
240 
241 		aprint_normal_dev(self, "console\n");
242 	}
243 
244 	sc->sc_si = softint_establish(SOFTINT_SERIAL, clpscom_soft, sc);
245 
246 #ifdef RND_COM
247 	rnd_attach_source(&sc->rnd_source, device_xname(sc->sc_dev),
248 	    RND_TYPE_TTY, RND_FLAG_DEFAULT);
249 #endif
250 
251 	SET(sc->sc_hwflags, COM_HW_DEV_OK);
252 }
253 
254 static int
255 clpscom_txintr(void *arg)
256 {
257 	struct clpscom_softc *sc = arg;
258 	uint32_t sysflg;
259 
260 	if (!device_is_active(sc->sc_dev))
261 		return 0;
262 
263 	sysflg = CLPSCOM_READ_FLG(sc);
264 
265 	/*
266 	 * Done handling any receive interrupts. See if data can be
267 	 * transmitted as well. Schedule tx done event if no data left
268 	 * and tty was marked busy.
269 	 */
270 
271 	if (!ISSET(sysflg, SYSFLG_UTXFF)) {
272 		/* Output the next chunk of the contiguous buffer, if any. */
273 		if (sc->sc_tbc > 0) {
274 			while (sc->sc_tbc > 0 && !ISSET(sysflg, SYSFLG_UTXFF)) {
275 				CLPSCOM_WRITE(sc, *sc->sc_tba);
276 				sc->sc_tba++;
277 				sc->sc_tbc--;
278 				sysflg = CLPSCOM_READ_FLG(sc);
279 			}
280 		} else if (!ISSET(sysflg, SYSFLG_UBUSY) &&
281 					sc->sc_ih[CLPSCOM_TXINT] != NULL) {
282 			intr_disestablish(sc->sc_ih[CLPSCOM_TXINT]);
283 			sc->sc_ih[CLPSCOM_TXINT] = NULL;
284 			sc->sc_tx_done = 1;
285 		}
286 	}
287 
288 	/* Wake up the poller. */
289 	softint_schedule(sc->sc_si);
290 
291 	return 1;
292 }
293 
294 static int
295 clpscom_rxintr(void *arg)
296 {
297 	struct clpscom_softc *sc = arg;
298 	int cc;
299 	uint32_t sysflg;
300 	uint16_t data;
301 	u_char *put;
302 
303 	if (!device_is_active(sc->sc_dev))
304 		return 0;
305 
306 	if (sc->sc_ih[CLPSCOM_RXINT] != NULL) {
307 		put = sc->sc_rbput;
308 		cc = sc->sc_rbavail;
309 		while (cc > 0) {
310 			sysflg = CLPSCOM_READ_FLG(sc);
311 			if (ISSET(sysflg, SYSFLG_URXFE))
312 				break;
313 			data = CLPSCOM_READ(sc);
314 			cn_check_magic(sc->sc_tty->t_dev, data & 0xff,
315 			    clpscom_cnm_state);
316 
317 			put[0] = data & 0xff;
318 			put[1] = (data >> 8) & 0xff;
319 			put += 2;
320 			if (put >= sc->sc_rbuf + (CLPSCOM_RING_SIZE << 1))
321 				put = sc->sc_rbuf;
322 			cc--;
323 			sc->sc_rx_ready = 1;
324 		}
325 
326 		/*
327 		 * Current string of incoming characters ended because
328 		 * no more data was available or we ran out of space.
329 		 * Schedule a receive event if any data was received.
330 		 * If we're out of space, turn off receive interrupts.
331 		 */
332 		sc->sc_rbput = put;
333 		sc->sc_rbavail = cc;
334 
335 		/*
336 		 * See if we are in danger of overflowing a buffer. If
337 		 * so, use hardware flow control to ease the pressure.
338 		 */
339 
340 		/* but clpscom cannot. X-( */
341 
342 		/*
343 		 * If we're out of space, disable receive interrupts
344 		 * until the queue has drained a bit.
345 		 */
346 		if (cc <= 0) {
347 			intr_disestablish(sc->sc_ih[CLPSCOM_RXINT]);
348 			sc->sc_ih[CLPSCOM_RXINT] = NULL;
349 		}
350 	}
351 
352 	/* Wake up the poller. */
353 	softint_schedule(sc->sc_si);
354 
355 	return 1;
356 }
357 
358 static int
359 clpscom_msintr(void *arg)
360 {
361 	struct clpscom_softc *sc = arg;
362 	uint32_t ms, delta;
363 
364 	if (!device_is_active(sc->sc_dev))
365 		return 0;
366 
367 	if (sc->sc_ih[CLPSCOM_MSINT] != NULL) {
368 		ms = CLPSCOM_READ_FLG(sc) & CLPSCOM_MODEM_STATUS_MASK;
369 		delta = ms ^ sc->sc_ms;
370 		sc->sc_ms = ms;
371 
372 		if (ISSET(delta, sc->sc_ms_mask)) {
373 			SET(sc->sc_ms_delta, delta);
374 
375 			/*
376 			 * Stop output immediately if we lose the output
377 			 * flow control signal or carrier detect.
378 			 */
379 			if (ISSET(~ms, sc->sc_ms_mask))
380 				sc->sc_tbc = 0;
381 			sc->sc_ms_changed = 1;
382 		}
383 	}
384 	bus_space_write_4(sc->sc_iot, sc->sc_ioh, PS711X_UMSEOI, 1);
385 
386 	/* Wake up the poller. */
387 	softint_schedule(sc->sc_si);
388 
389 	return 1;
390 }
391 
392 static void
393 clpscom_soft(void *arg)
394 {
395 	struct clpscom_softc *sc = arg;
396 	struct tty *tp = sc->sc_tty;
397 
398 	if (!device_is_active(sc->sc_dev))
399 		return;
400 
401 	if (sc->sc_rx_ready) {
402 		sc->sc_rx_ready = 0;
403 		clpscom_rxsoft(sc, tp);
404 	}
405 	if (sc->sc_tx_done) {
406 		sc->sc_tx_done = 0;
407 		CLR(tp->t_state, TS_BUSY);
408 		if (ISSET(tp->t_state, TS_FLUSH))
409 			CLR(tp->t_state, TS_FLUSH);
410 		else
411 			ndflush(&tp->t_outq,
412 			    (int)(sc->sc_tba - tp->t_outq.c_cf));
413 		(*tp->t_linesw->l_start)(tp);
414 	}
415 	if (sc->sc_ms_changed == 1) {
416 		sc->sc_ms_changed = 0;
417 		clpscom_mssoft(sc, tp);
418 	}
419 }
420 
421 static void
422 clpscom_start(struct tty *tp)
423 {
424 	struct clpscom_softc *sc
425 		= device_lookup_private(&clpscom_cd, COMUNIT(tp->t_dev));
426 	int s, n;
427 
428 	if (!device_is_active(sc->sc_dev))
429 		return;
430 
431 	s = spltty();
432 	if (ISSET(tp->t_state, TS_BUSY | TS_TIMEOUT | TS_TTSTOP))
433 		goto out;
434 	if (sc->sc_tx_stopped)
435 		goto out;
436 	if (!ttypull(tp))
437 		goto out;
438 
439 	/* Grab the first contiguous region of buffer space. */
440 	{
441 		u_char *tba;
442 		int tbc;
443 
444 		tba = tp->t_outq.c_cf;
445 		tbc = ndqb(&tp->t_outq, 0);
446 
447 		(void)splserial();
448 
449 		sc->sc_tba = tba;
450 		sc->sc_tbc = tbc;
451 	}
452 
453 	SET(tp->t_state, TS_BUSY);
454 
455 	if (sc->sc_ih[CLPSCOM_TXINT] == NULL) {
456 		sc->sc_ih[CLPSCOM_TXINT] =
457 		    intr_establish(sc->sc_irq[CLPSCOM_TXINT], IPL_SERIAL, 0,
458 		    clpscom_txintr, sc);
459 		if (sc->sc_ih[CLPSCOM_TXINT] == NULL)
460 			printf("%s: can't establish tx interrupt\n",
461 			    device_xname(sc->sc_dev));
462 
463 		/* Output the first chunk of the contiguous buffer. */
464 		n = min(sc->sc_tbc, UART_FIFO_SIZE);
465 		CLPSCOM_WRITE_MULTI(sc, sc->sc_tba, n);
466 		sc->sc_tba += n;
467 		sc->sc_tbc -= n;
468 	}
469 out:
470 	splx(s);
471 	return;
472 }
473 
474 static int
475 clpscom_param(struct tty *tp, struct termios *t)
476 {
477 	struct clpscom_softc *sc =
478 	    device_lookup_private(&clpscom_cd, COMUNIT(tp->t_dev));
479 	int s;
480 
481 	if (!device_is_active(sc->sc_dev))
482 		return ENXIO;
483 	if (t->c_ispeed && t->c_ispeed != t->c_ospeed)
484 		return EINVAL;
485 
486 	/*
487 	 * For the console, always force CLOCAL and !HUPCL, so that the port
488 	 * is always active.
489 	 */
490 	if (ISSET(sc->sc_swflags, TIOCFLAG_SOFTCAR) ||
491 	    ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
492 		SET(t->c_cflag, CLOCAL);
493 		CLR(t->c_cflag, HUPCL);
494 	}
495 
496 	/*
497 	 * If there were no changes, don't do anything.  This avoids dropping
498 	 * input and improves performance when all we did was frob things like
499 	 * VMIN and VTIME.
500 	 */
501 	if (tp->t_ospeed == t->c_ospeed &&
502 	    tp->t_cflag == t->c_cflag)
503 		return 0;
504 
505 	/*
506 	 * If we're not in a mode that assumes a connection is present, then
507 	 * ignore carrier changes.
508 	 */
509 	if (ISSET(t->c_cflag, CLOCAL | MDMBUF))
510 		sc->sc_ms_dcd = 0;
511 	else
512 		sc->sc_ms_dcd = SYSFLG_DCD;
513 	/*
514 	 * Set the flow control pins depending on the current flow control
515 	 * mode.
516 	 */
517 	if (ISSET(t->c_cflag, CRTSCTS)) {
518 		sc->sc_ms_cts = SYSFLG_CTS;
519 	} else if (ISSET(t->c_cflag, MDMBUF)) {
520 		/*
521 		 * For DTR/DCD flow control, make sure we don't toggle DTR for
522 		 * carrier detection.
523 		 */
524 		sc->sc_ms_cts = SYSFLG_DCD;
525 	} else {
526 		/*
527 		 * If no flow control, then always set RTS.  This will make
528 		 * the other side happy if it mistakenly thinks we're doing
529 		 * RTS/CTS flow control.
530 		 */
531 		sc->sc_ms_cts = 0;
532 	}
533 	sc->sc_ms_mask = sc->sc_ms_cts | sc->sc_ms_dcd;
534 
535 	s = splserial();
536 	CLPSCOM_WRITE_UBRLCR(sc,
537 	    UBRLCR_FIFOEN |
538 	    clpscom_rate2ubrlcr(t->c_ospeed) |
539 	    clpscom_cflag2ubrlcr(t->c_cflag));
540 
541 	/* And copy to tty. */
542 	tp->t_ispeed = 0;
543 	tp->t_ospeed = t->c_ospeed;
544 	tp->t_cflag = t->c_cflag;
545 	splx(s);
546 
547 	/*
548 	 * Update the tty layer's idea of the carrier bit, in case we changed
549 	 * CLOCAL or MDMBUF.  We don't hang up here; we only do that by
550 	 * explicit request.
551 	 */
552 	(*tp->t_linesw->l_modem)(tp, ISSET(sc->sc_ms, SYSFLG_DCD));
553 
554 	if (!ISSET(t->c_cflag, CHWFLOW))
555 		if (sc->sc_tx_stopped) {
556 			sc->sc_tx_stopped = 0;
557 			clpscom_start(tp);
558 		}
559 
560 	return 0;
561 }
562 
563 static int
564 clpscom_hwiflow(struct tty *tp, int block)
565 {
566 	/* Nothing */
567 	return 0;
568 }
569 
570 /* ARGSUSED */
571 int
572 clpscomopen(dev_t dev, int flag, int mode, struct lwp *l)
573 {
574 	struct clpscom_softc *sc;
575 	struct tty *tp;
576 	int error, s, s2;
577 
578 	sc = device_lookup_private(&clpscom_cd, COMUNIT(dev));
579 	if (sc == NULL || !ISSET(sc->sc_hwflags, COM_HW_DEV_OK))
580 		return ENXIO;
581 	if (!device_is_active(sc->sc_dev))
582 		return ENXIO;
583 
584 #ifdef KGDB
585 	/*
586 	 * If this is the kgdb port, no other use is permitted.
587 	 */
588 	if (ISSET(sc->sc_hwflags, COM_HW_KGDB))
589 		return EBUSY;
590 #endif
591 
592 	tp = sc->sc_tty;
593 
594 	if (kauth_authorize_device_tty(l->l_cred, KAUTH_DEVICE_TTY_OPEN, tp))
595 		return EBUSY;
596 
597 	s = spltty();
598 
599 	/*
600 	 * Do the following iff this is a first open.
601 	 */
602 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
603 		struct termios t;
604 
605 		tp->t_dev = dev;
606 
607 		/* Enable and turn on interrupt */
608 		CLPSCOM_WRITE_CON(sc, CLPSCOM_READ_CON(sc) | SYSCON_UARTEN);
609 
610 		/* Fetch the current modem control status, needed later. */
611 		sc->sc_ms = CLPSCOM_READ_FLG(sc) & CLPSCOM_MODEM_STATUS_MASK;
612 
613 		/*
614 		 * Initialize the termios status to the defaults.  Add in the
615 		 * sticky bits from TIOCSFLAGS.
616 		 */
617 		t.c_ispeed = 0;
618 		if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
619 			t.c_ospeed = clpscom_cnrate;
620 			t.c_cflag = clpscom_cncflag;
621 		} else {
622 			t.c_ospeed = TTYDEF_SPEED;
623 			t.c_cflag = TTYDEF_CFLAG;
624 		}
625 		if (ISSET(sc->sc_swflags, TIOCFLAG_CLOCAL))
626 			SET(t.c_cflag, CLOCAL);
627 		if (ISSET(sc->sc_swflags, TIOCFLAG_CRTSCTS))
628 			SET(t.c_cflag, CRTSCTS);
629 		if (ISSET(sc->sc_swflags, TIOCFLAG_MDMBUF))
630 			SET(t.c_cflag, MDMBUF);
631 		/* Make sure pscom_param() we do something */
632 		tp->t_ospeed = 0;
633 		clpscom_param(tp, &t);
634 		tp->t_iflag = TTYDEF_IFLAG;
635 		tp->t_oflag = TTYDEF_OFLAG;
636 		tp->t_lflag = TTYDEF_LFLAG;
637 		ttychars(tp);
638 		ttsetwater(tp);
639 
640 		s2 = splserial();
641 
642 		/* Clear the input ring. */
643 		sc->sc_rbput = sc->sc_rbget = sc->sc_rbuf;
644 		sc->sc_rbavail = CLPSCOM_RING_SIZE;
645 		clpscom_iflush(sc);
646 
647 		splx(s2);
648 	}
649 
650 	splx(s);
651 
652 	error = ttyopen(tp, COMDIALOUT(dev), ISSET(flag, O_NONBLOCK));
653 	if (error)
654 		goto bad;
655 
656 	error = (*tp->t_linesw->l_open)(dev, tp);
657 	if (error)
658 		goto bad;
659 	return 0;
660 
661 bad:
662 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
663 		/*
664 		 * We failed to open the device, and nobody else had it opened.
665 		 * Clean up the state as appropriate.
666 		 */
667 		clpscom_shutdown(sc);
668 
669 		/* Disable UART */
670 		if (!ISSET(sc->sc_hwflags, COM_HW_CONSOLE))
671 			CLPSCOM_WRITE_CON(sc,
672 			    CLPSCOM_READ_CON(sc) & ~SYSCON_UARTEN);
673 	}
674 
675 	return error;
676 }
677 
678 /* ARGSUSED */
679 int
680 clpscomclose(dev_t dev, int flag, int mode, struct lwp *l)
681 {
682 	struct clpscom_softc *sc =
683 	    device_lookup_private(&clpscom_cd, COMUNIT(dev));
684 	struct tty *tp = sc->sc_tty;
685 
686 	/* XXXX This is for cons.c. */
687 	if (!ISSET(tp->t_state, TS_ISOPEN))
688 		return 0;
689 
690 	(*tp->t_linesw->l_close)(tp, flag);
691 	ttyclose(tp);
692 
693 	if (!device_is_active(sc->sc_dev))
694 		return 0;
695 
696 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
697 		/*
698 		 * Although we got a last close, the device may still be in
699 		 * use; e.g. if this was the dialout node, and there are still
700 		 * processes waiting for carrier on the non-dialout node.
701 		 */
702 		clpscom_shutdown(sc);
703 
704 		/* Disable UART */
705 		if (!ISSET(sc->sc_hwflags, COM_HW_CONSOLE))
706 			CLPSCOM_WRITE_CON(sc,
707 			    CLPSCOM_READ_CON(sc) & ~SYSCON_UARTEN);
708 	}
709 
710 	return 0;
711 }
712 
713 int
714 clpscomread(dev_t dev, struct uio *uio, int flag)
715 {
716 	struct clpscom_softc *sc =
717 	    device_lookup_private(&clpscom_cd, COMUNIT(dev));
718 	struct tty *tp = sc->sc_tty;
719 
720 	if (!device_is_active(sc->sc_dev))
721 		return EIO;
722 
723 	return (*tp->t_linesw->l_read)(tp, uio, flag);
724 }
725 
726 int
727 clpscomwrite(dev_t dev, struct uio *uio, int flag)
728 {
729 	struct clpscom_softc *sc =
730 	    device_lookup_private(&clpscom_cd, COMUNIT(dev));
731 	struct tty *tp = sc->sc_tty;
732 
733 	if (!device_is_active(sc->sc_dev))
734 		return EIO;
735 
736 	return (*tp->t_linesw->l_write)(tp, uio, flag);
737 }
738 
739 int
740 clpscomioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l)
741 {
742 	struct clpscom_softc *sc =
743 	    device_lookup_private(&clpscom_cd, COMUNIT(dev));
744 	struct tty *tp = sc->sc_tty;
745 	int error, s;
746 
747 	if (!device_is_active(sc->sc_dev))
748 		return EIO;
749 
750 	error = (*tp->t_linesw->l_ioctl)(tp, cmd, data, flag, l);
751 	if (error != EPASSTHROUGH)
752 		return error;
753 
754 	error = ttioctl(tp, cmd, data, flag, l);
755 	if (error != EPASSTHROUGH)
756 		return error;
757 
758 	switch (cmd) {
759 	case TIOCSFLAGS:
760 		error = kauth_authorize_device_tty(l->l_cred,
761 		    KAUTH_DEVICE_TTY_PRIVSET, tp);
762 		break;
763 	default:
764 		break;
765 	}
766 	if (error)
767 		return error;
768 
769 	s = splserial();
770 	error = 0;
771 	switch (cmd) {
772 	case TIOCSBRK:
773 		clpscom_break(sc, 1);
774 		break;
775 
776 	case TIOCCBRK:
777 		clpscom_break(sc, 0);
778 		break;
779 
780 	case TIOCGFLAGS:
781 		*(int *)data = sc->sc_swflags;
782 		break;
783 
784 	case TIOCSFLAGS:
785 		sc->sc_swflags = *(int *)data;
786 		break;
787 
788 	case TIOCMGET:
789 		*(int *)data = clpscom_to_tiocm(sc);
790 		break;
791 
792 	default:
793 		error = EPASSTHROUGH;
794 		break;
795 	}
796 	splx(s);
797 	return error;
798 }
799 
800 int
801 clpscompoll(dev_t dev, int events, struct lwp *l)
802 {
803 	struct clpscom_softc *sc =
804 	    device_lookup_private(&clpscom_cd, COMUNIT(dev));
805 	struct tty *tp = sc->sc_tty;
806 
807 	if (!device_is_active(sc->sc_dev))
808 		return EIO;
809 
810 	return (*tp->t_linesw->l_poll)(tp, events, l);
811 }
812 
813 struct tty *
814 clpscomtty(dev_t dev)
815 {
816 	struct clpscom_softc *sc =
817 	    device_lookup_private(&clpscom_cd, COMUNIT(dev));
818 
819 	return sc->sc_tty;
820 }
821 
822 void
823 clpscomstop(struct tty *tp, int flag)
824 {
825 	int s;
826 
827 	s = splserial();
828 	if (ISSET(tp->t_state, TS_BUSY)) {
829 		/* Stop transmitting at the next chunk. */
830 		if (!ISSET(tp->t_state, TS_TTSTOP))
831 			SET(tp->t_state, TS_FLUSH);
832 	}
833 	splx(s);
834 }
835 
836 
837 static void
838 clpscom_iflush(struct clpscom_softc *sc)
839 {
840 	int timo;
841 
842 	timo = 50000;
843 	while ((CLPSCOM_READ_FLG(sc) & SYSFLG_URXFE) == 0
844 	    && timo--)
845 		CLPSCOM_READ(sc);
846 	if (timo == 0)
847 		printf("%s: iflush timeout\n", device_xname(sc->sc_dev));
848 }
849 
850 static void
851 clpscom_shutdown(struct clpscom_softc *sc)
852 {
853 	int s;
854 
855 	s = splserial();
856 
857 	/* Turn off all interrupts */
858 	if (sc->sc_ih[CLPSCOM_TXINT] != NULL)
859 		intr_disestablish(sc->sc_ih[CLPSCOM_TXINT]);
860 	sc->sc_ih[CLPSCOM_TXINT] = NULL;
861 	if (sc->sc_ih[CLPSCOM_RXINT] != NULL)
862 		intr_disestablish(sc->sc_ih[CLPSCOM_RXINT]);
863 	sc->sc_ih[CLPSCOM_RXINT] = NULL;
864 	if (sc->sc_ih[CLPSCOM_MSINT] != NULL)
865 		intr_disestablish(sc->sc_ih[CLPSCOM_MSINT]);
866 	sc->sc_ih[CLPSCOM_MSINT] = NULL;
867 
868 	/* Clear any break condition set with TIOCSBRK. */
869 	clpscom_break(sc, 0);
870 
871 	splx(s);
872 }
873 
874 static void
875 clpscom_break(struct clpscom_softc *sc, int onoff)
876 {
877 	int s;
878 	uint8_t ubrlcr;
879 
880 	s = splserial();
881 	ubrlcr = CLPSCOM_READ_UBRLCR(sc);
882 	if (onoff)
883 		SET(ubrlcr, UBRLCR_BREAK);
884 	else
885 		CLR(ubrlcr, UBRLCR_BREAK);
886 	CLPSCOM_WRITE_UBRLCR(sc, ubrlcr);
887 	splx(s);
888 }
889 
890 static int
891 clpscom_to_tiocm(struct clpscom_softc *sc)
892 {
893 	uint32_t combits;
894 	int ttybits = 0;
895 
896 	combits = sc->sc_ms;
897 	if (ISSET(combits, SYSFLG_DCD))
898 		SET(ttybits, TIOCM_CD);
899 	if (ISSET(combits, SYSFLG_CTS))
900 		SET(ttybits, TIOCM_CTS);
901 	if (ISSET(combits, SYSFLG_DSR))
902 		SET(ttybits, TIOCM_DSR);
903 
904 	return ttybits;
905 }
906 
907 static void
908 clpscom_rxsoft(struct clpscom_softc *sc, struct tty *tp)
909 {
910 	int code, s;
911 	u_int cc, scc;
912 	u_char sts, *get;
913 
914 	get = sc->sc_rbget;
915 	scc = cc = CLPSCOM_RING_SIZE - sc->sc_rbavail;
916 	while (cc) {
917 		code = get[0];
918 		sts = get[1];
919 		if (ISSET(sts, UARTDR_FRMERR | UARTDR_PARERR | UARTDR_OVERR)) {
920 			if (ISSET(sts, (UARTDR_FRMERR)))
921 				SET(code, TTY_FE);
922 			if (ISSET(sts, UARTDR_PARERR))
923 				SET(code, TTY_PE);
924 			if (ISSET(sts, UARTDR_OVERR))
925 				;		/* XXXXX: Overrun */
926 		}
927 		if ((*tp->t_linesw->l_rint)(code, tp) == -1) {
928 			/*
929 			 * The line discipline's buffer is out of space.
930 			 */
931 			/*
932 			 * We're either not using flow control, or the
933 			 * line discipline didn't tell us to block for
934 			 * some reason.  Either way, we have no way to
935 			 * know when there's more space available, so
936 			 * just drop the rest of the data.
937 			 */
938 			get += cc << 1;
939 			if (get >= sc->sc_rbuf + (CLPSCOM_RING_SIZE << 1))
940 				get -= (CLPSCOM_RING_SIZE << 1);
941 			cc = 0;
942 			break;
943 		}
944 		get += 2;
945 		if (get >= sc->sc_rbuf + (CLPSCOM_RING_SIZE << 1))
946 			get = sc->sc_rbuf;
947 		cc--;
948 	}
949 
950 	if (cc != scc) {
951 		sc->sc_rbget = get;
952 		s = splserial();
953 
954 		cc = sc->sc_rbavail += scc - cc;
955 		/* Buffers should be ok again, release possible block. */
956 		if (cc >= 1) {
957 			if (sc->sc_ih[CLPSCOM_RXINT] == NULL) {
958 				sc->sc_ih[CLPSCOM_RXINT] =
959 				    intr_establish(sc->sc_irq[CLPSCOM_RXINT],
960 				    IPL_SERIAL, 0, clpscom_rxintr, sc);
961 				if (sc->sc_ih[CLPSCOM_RXINT] == NULL)
962 					printf("%s: can't establish"
963 					    " rx interrupt\n",
964 					    device_xname(sc->sc_dev));
965 			}
966 			if (sc->sc_ih[CLPSCOM_MSINT] == NULL) {
967 				sc->sc_ih[CLPSCOM_MSINT] =
968 				    intr_establish(sc->sc_irq[CLPSCOM_MSINT],
969 				    IPL_SERIAL, 0, clpscom_msintr, sc);
970 				if (sc->sc_ih[CLPSCOM_MSINT] == NULL)
971 					printf("%s: can't establish"
972 					    " ms interrupt\n",
973 					    device_xname(sc->sc_dev));
974 			}
975 		}
976 		splx(s);
977 	}
978 }
979 
980 static void
981 clpscom_mssoft(struct clpscom_softc *sc, struct tty *tp)
982 {
983 	uint32_t ms, delta;
984 
985 	ms = sc->sc_ms;
986 	delta = sc->sc_ms_delta;
987 	sc->sc_ms_delta = 0;
988 
989 	if (ISSET(delta, sc->sc_ms_dcd))
990 		/*
991 		 * Inform the tty layer that carrier detect changed.
992 		 */
993 		(void) (*tp->t_linesw->l_modem)(tp, ISSET(ms, SYSFLG_DCD));
994 
995 	if (ISSET(delta, sc->sc_ms_cts)) {
996 		/* Block or unblock output according to flow control. */
997 		if (ISSET(ms, sc->sc_ms_cts)) {
998 			sc->sc_tx_stopped = 0;
999 			(*tp->t_linesw->l_start)(tp);
1000 		} else
1001 			sc->sc_tx_stopped = 1;
1002 	}
1003 }
1004 
1005 static inline uint32_t
1006 clpscom_rate2ubrlcr(int rate)
1007 {
1008 
1009 	return 230400 / rate - 1;
1010 }
1011 
1012 static uint32_t
1013 clpscom_cflag2ubrlcr(tcflag_t cflag)
1014 {
1015 	int32_t ubrlcr = 0;
1016 
1017 	switch (cflag & CSIZE) {
1018 	case CS5: SET(ubrlcr, UBRLCR_WRDLEN_5B); break;
1019 	case CS6: SET(ubrlcr, UBRLCR_WRDLEN_6B); break;
1020 	case CS7: SET(ubrlcr, UBRLCR_WRDLEN_7B); break;
1021 	case CS8: SET(ubrlcr, UBRLCR_WRDLEN_8B); break;
1022 	default:  SET(ubrlcr, UBRLCR_WRDLEN_8B); break;
1023 	}
1024 	if (cflag & CSTOPB)
1025 		SET(ubrlcr, UBRLCR_XSTOP);
1026 	if (cflag & PARENB) {
1027 		SET(ubrlcr, (UBRLCR_PRTEN | UBRLCR_EVENPRT));
1028 		if (cflag & PARODD)
1029 			CLR(ubrlcr, UBRLCR_EVENPRT);
1030 	}
1031 	return ubrlcr;
1032 }
1033 
1034 #define CLPSCOM_CNREAD() \
1035 	(*(volatile uint32_t *)(clpscom_cnaddr + PS711X_UARTDR))
1036 #define CLPSCOM_CNWRITE(val) \
1037 	(*(volatile uint8_t *)(clpscom_cnaddr + PS711X_UARTDR) = val)
1038 #define CLPSCOM_CNSTATUS() \
1039 	(*(volatile uint32_t *)(clpscom_cnaddr + PS711X_SYSFLG))
1040 
1041 static struct consdev clpscomcons = {
1042 	NULL, NULL, clpscom_cngetc, clpscom_cnputc, clpscom_cnpollc,
1043 	NULL, NULL, NULL, NODEV, CN_NORMAL
1044 };
1045 
1046 int
1047 clpscom_cnattach(vaddr_t addr, int rate, tcflag_t cflag)
1048 {
1049 
1050 	clpscom_cnaddr = addr;
1051 	clpscom_cnrate = rate;
1052 	clpscom_cncflag = cflag;
1053 	*(volatile uint32_t *)(clpscom_cnaddr + PS711X_SYSFLG) |= SYSCON_UARTEN;
1054 	*(volatile uint32_t *)(clpscom_cnaddr + PS711X_UBRLCR) =
1055 	    UBRLCR_FIFOEN |
1056 	    clpscom_cflag2ubrlcr(cflag) |
1057 	    clpscom_rate2ubrlcr(rate);
1058 
1059 	cn_tab = &clpscomcons;
1060 	cn_init_magic(&clpscom_cnm_state);
1061 	cn_set_magic("\047\001");	/* default magic is BREAK */
1062 
1063 	return 0;
1064 }
1065 
1066 /* ARGSUSED */
1067 static int
1068 clpscom_cngetc(dev_t dev)
1069 {
1070 	int s = splserial();
1071 	char ch;
1072 
1073 	while (CLPSCOM_CNSTATUS() & SYSFLG_URXFE);
1074 
1075 	ch = CLPSCOM_CNREAD();
1076 
1077 	{
1078 #ifdef DDB
1079 		extern int db_active;
1080 		if (!db_active)
1081 #endif
1082 			cn_check_magic(dev, ch, clpscom_cnm_state);
1083 	}
1084 
1085 	splx(s);
1086 	return ch;
1087 }
1088 
1089 /* ARGSUSED */
1090 static void
1091 clpscom_cnputc(dev_t dev, int c)
1092 {
1093 	int s = splserial();
1094 
1095 	while (CLPSCOM_CNSTATUS() & SYSFLG_UTXFF);
1096 
1097 	CLPSCOM_CNWRITE(c);
1098 
1099 	/* Make sure output. */
1100 	while (CLPSCOM_CNSTATUS() & SYSFLG_UBUSY);
1101 
1102 	splx(s);
1103 }
1104 
1105 /* ARGSUSED */
1106 static void
1107 clpscom_cnpollc(dev_t dev, int on)
1108 {
1109 	/* Nothing */
1110 }
1111