xref: /netbsd-src/sys/arch/arm/clps711x/clpscom.c (revision 82d56013d7b633d116a93943de88e08335357a7c)
1 /*      $NetBSD: clpscom.c,v 1.9 2020/11/20 18:03:52 thorpej 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 1.9 2020/11/20 18:03:52 thorpej 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/kmem.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 = kmem_alloc(CLPSCOM_RING_SIZE << 1, KM_SLEEP);
226 	sc->sc_rbput = sc->sc_rbget = sc->sc_rbuf;
227 	sc->sc_rbavail = CLPSCOM_RING_SIZE;
228 
229 	tty_attach(sc->sc_tty);
230 
231 	if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
232 		int maj = cdevsw_lookup_major(&clpscom_cdevsw);
233 
234 		sc->sc_tty->t_dev = makedev(maj, device_unit(sc->sc_dev));
235 		cn_tab->cn_dev = sc->sc_tty->t_dev;
236 
237 		aprint_normal_dev(self, "console\n");
238 	}
239 
240 	sc->sc_si = softint_establish(SOFTINT_SERIAL, clpscom_soft, sc);
241 
242 #ifdef RND_COM
243 	rnd_attach_source(&sc->rnd_source, device_xname(sc->sc_dev),
244 	    RND_TYPE_TTY, RND_FLAG_DEFAULT);
245 #endif
246 
247 	SET(sc->sc_hwflags, COM_HW_DEV_OK);
248 }
249 
250 static int
251 clpscom_txintr(void *arg)
252 {
253 	struct clpscom_softc *sc = arg;
254 	uint32_t sysflg;
255 
256 	if (!device_is_active(sc->sc_dev))
257 		return 0;
258 
259 	sysflg = CLPSCOM_READ_FLG(sc);
260 
261 	/*
262 	 * Done handling any receive interrupts. See if data can be
263 	 * transmitted as well. Schedule tx done event if no data left
264 	 * and tty was marked busy.
265 	 */
266 
267 	if (!ISSET(sysflg, SYSFLG_UTXFF)) {
268 		/* Output the next chunk of the contiguous buffer, if any. */
269 		if (sc->sc_tbc > 0) {
270 			while (sc->sc_tbc > 0 && !ISSET(sysflg, SYSFLG_UTXFF)) {
271 				CLPSCOM_WRITE(sc, *sc->sc_tba);
272 				sc->sc_tba++;
273 				sc->sc_tbc--;
274 				sysflg = CLPSCOM_READ_FLG(sc);
275 			}
276 		} else if (!ISSET(sysflg, SYSFLG_UBUSY) &&
277 					sc->sc_ih[CLPSCOM_TXINT] != NULL) {
278 			intr_disestablish(sc->sc_ih[CLPSCOM_TXINT]);
279 			sc->sc_ih[CLPSCOM_TXINT] = NULL;
280 			sc->sc_tx_done = 1;
281 		}
282 	}
283 
284 	/* Wake up the poller. */
285 	softint_schedule(sc->sc_si);
286 
287 	return 1;
288 }
289 
290 static int
291 clpscom_rxintr(void *arg)
292 {
293 	struct clpscom_softc *sc = arg;
294 	int cc;
295 	uint32_t sysflg;
296 	uint16_t data;
297 	u_char *put;
298 
299 	if (!device_is_active(sc->sc_dev))
300 		return 0;
301 
302 	if (sc->sc_ih[CLPSCOM_RXINT] != NULL) {
303 		put = sc->sc_rbput;
304 		cc = sc->sc_rbavail;
305 		while (cc > 0) {
306 			sysflg = CLPSCOM_READ_FLG(sc);
307 			if (ISSET(sysflg, SYSFLG_URXFE))
308 				break;
309 			data = CLPSCOM_READ(sc);
310 			cn_check_magic(sc->sc_tty->t_dev, data & 0xff,
311 			    clpscom_cnm_state);
312 
313 			put[0] = data & 0xff;
314 			put[1] = (data >> 8) & 0xff;
315 			put += 2;
316 			if (put >= sc->sc_rbuf + (CLPSCOM_RING_SIZE << 1))
317 				put = sc->sc_rbuf;
318 			cc--;
319 			sc->sc_rx_ready = 1;
320 		}
321 
322 		/*
323 		 * Current string of incoming characters ended because
324 		 * no more data was available or we ran out of space.
325 		 * Schedule a receive event if any data was received.
326 		 * If we're out of space, turn off receive interrupts.
327 		 */
328 		sc->sc_rbput = put;
329 		sc->sc_rbavail = cc;
330 
331 		/*
332 		 * See if we are in danger of overflowing a buffer. If
333 		 * so, use hardware flow control to ease the pressure.
334 		 */
335 
336 		/* but clpscom cannot. X-( */
337 
338 		/*
339 		 * If we're out of space, disable receive interrupts
340 		 * until the queue has drained a bit.
341 		 */
342 		if (cc <= 0) {
343 			intr_disestablish(sc->sc_ih[CLPSCOM_RXINT]);
344 			sc->sc_ih[CLPSCOM_RXINT] = NULL;
345 		}
346 	}
347 
348 	/* Wake up the poller. */
349 	softint_schedule(sc->sc_si);
350 
351 	return 1;
352 }
353 
354 static int
355 clpscom_msintr(void *arg)
356 {
357 	struct clpscom_softc *sc = arg;
358 	uint32_t ms, delta;
359 
360 	if (!device_is_active(sc->sc_dev))
361 		return 0;
362 
363 	if (sc->sc_ih[CLPSCOM_MSINT] != NULL) {
364 		ms = CLPSCOM_READ_FLG(sc) & CLPSCOM_MODEM_STATUS_MASK;
365 		delta = ms ^ sc->sc_ms;
366 		sc->sc_ms = ms;
367 
368 		if (ISSET(delta, sc->sc_ms_mask)) {
369 			SET(sc->sc_ms_delta, delta);
370 
371 			/*
372 			 * Stop output immediately if we lose the output
373 			 * flow control signal or carrier detect.
374 			 */
375 			if (ISSET(~ms, sc->sc_ms_mask))
376 				sc->sc_tbc = 0;
377 			sc->sc_ms_changed = 1;
378 		}
379 	}
380 	bus_space_write_4(sc->sc_iot, sc->sc_ioh, PS711X_UMSEOI, 1);
381 
382 	/* Wake up the poller. */
383 	softint_schedule(sc->sc_si);
384 
385 	return 1;
386 }
387 
388 static void
389 clpscom_soft(void *arg)
390 {
391 	struct clpscom_softc *sc = arg;
392 	struct tty *tp = sc->sc_tty;
393 
394 	if (!device_is_active(sc->sc_dev))
395 		return;
396 
397 	if (sc->sc_rx_ready) {
398 		sc->sc_rx_ready = 0;
399 		clpscom_rxsoft(sc, tp);
400 	}
401 	if (sc->sc_tx_done) {
402 		sc->sc_tx_done = 0;
403 		CLR(tp->t_state, TS_BUSY);
404 		if (ISSET(tp->t_state, TS_FLUSH))
405 			CLR(tp->t_state, TS_FLUSH);
406 		else
407 			ndflush(&tp->t_outq,
408 			    (int)(sc->sc_tba - tp->t_outq.c_cf));
409 		(*tp->t_linesw->l_start)(tp);
410 	}
411 	if (sc->sc_ms_changed == 1) {
412 		sc->sc_ms_changed = 0;
413 		clpscom_mssoft(sc, tp);
414 	}
415 }
416 
417 static void
418 clpscom_start(struct tty *tp)
419 {
420 	struct clpscom_softc *sc
421 		= device_lookup_private(&clpscom_cd, COMUNIT(tp->t_dev));
422 	int s, n;
423 
424 	if (!device_is_active(sc->sc_dev))
425 		return;
426 
427 	s = spltty();
428 	if (ISSET(tp->t_state, TS_BUSY | TS_TIMEOUT | TS_TTSTOP))
429 		goto out;
430 	if (sc->sc_tx_stopped)
431 		goto out;
432 	if (!ttypull(tp))
433 		goto out;
434 
435 	/* Grab the first contiguous region of buffer space. */
436 	{
437 		u_char *tba;
438 		int tbc;
439 
440 		tba = tp->t_outq.c_cf;
441 		tbc = ndqb(&tp->t_outq, 0);
442 
443 		(void)splserial();
444 
445 		sc->sc_tba = tba;
446 		sc->sc_tbc = tbc;
447 	}
448 
449 	SET(tp->t_state, TS_BUSY);
450 
451 	if (sc->sc_ih[CLPSCOM_TXINT] == NULL) {
452 		sc->sc_ih[CLPSCOM_TXINT] =
453 		    intr_establish(sc->sc_irq[CLPSCOM_TXINT], IPL_SERIAL, 0,
454 		    clpscom_txintr, sc);
455 		if (sc->sc_ih[CLPSCOM_TXINT] == NULL)
456 			printf("%s: can't establish tx interrupt\n",
457 			    device_xname(sc->sc_dev));
458 
459 		/* Output the first chunk of the contiguous buffer. */
460 		n = uimin(sc->sc_tbc, UART_FIFO_SIZE);
461 		CLPSCOM_WRITE_MULTI(sc, sc->sc_tba, n);
462 		sc->sc_tba += n;
463 		sc->sc_tbc -= n;
464 	}
465 out:
466 	splx(s);
467 	return;
468 }
469 
470 static int
471 clpscom_param(struct tty *tp, struct termios *t)
472 {
473 	struct clpscom_softc *sc =
474 	    device_lookup_private(&clpscom_cd, COMUNIT(tp->t_dev));
475 	int s;
476 
477 	if (!device_is_active(sc->sc_dev))
478 		return ENXIO;
479 	if (t->c_ispeed && t->c_ispeed != t->c_ospeed)
480 		return EINVAL;
481 
482 	/*
483 	 * For the console, always force CLOCAL and !HUPCL, so that the port
484 	 * is always active.
485 	 */
486 	if (ISSET(sc->sc_swflags, TIOCFLAG_SOFTCAR) ||
487 	    ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
488 		SET(t->c_cflag, CLOCAL);
489 		CLR(t->c_cflag, HUPCL);
490 	}
491 
492 	/*
493 	 * If there were no changes, don't do anything.  This avoids dropping
494 	 * input and improves performance when all we did was frob things like
495 	 * VMIN and VTIME.
496 	 */
497 	if (tp->t_ospeed == t->c_ospeed &&
498 	    tp->t_cflag == t->c_cflag)
499 		return 0;
500 
501 	/*
502 	 * If we're not in a mode that assumes a connection is present, then
503 	 * ignore carrier changes.
504 	 */
505 	if (ISSET(t->c_cflag, CLOCAL | MDMBUF))
506 		sc->sc_ms_dcd = 0;
507 	else
508 		sc->sc_ms_dcd = SYSFLG_DCD;
509 	/*
510 	 * Set the flow control pins depending on the current flow control
511 	 * mode.
512 	 */
513 	if (ISSET(t->c_cflag, CRTSCTS)) {
514 		sc->sc_ms_cts = SYSFLG_CTS;
515 	} else if (ISSET(t->c_cflag, MDMBUF)) {
516 		/*
517 		 * For DTR/DCD flow control, make sure we don't toggle DTR for
518 		 * carrier detection.
519 		 */
520 		sc->sc_ms_cts = SYSFLG_DCD;
521 	} else {
522 		/*
523 		 * If no flow control, then always set RTS.  This will make
524 		 * the other side happy if it mistakenly thinks we're doing
525 		 * RTS/CTS flow control.
526 		 */
527 		sc->sc_ms_cts = 0;
528 	}
529 	sc->sc_ms_mask = sc->sc_ms_cts | sc->sc_ms_dcd;
530 
531 	s = splserial();
532 	CLPSCOM_WRITE_UBRLCR(sc,
533 	    UBRLCR_FIFOEN |
534 	    clpscom_rate2ubrlcr(t->c_ospeed) |
535 	    clpscom_cflag2ubrlcr(t->c_cflag));
536 
537 	/* And copy to tty. */
538 	tp->t_ispeed = 0;
539 	tp->t_ospeed = t->c_ospeed;
540 	tp->t_cflag = t->c_cflag;
541 	splx(s);
542 
543 	/*
544 	 * Update the tty layer's idea of the carrier bit, in case we changed
545 	 * CLOCAL or MDMBUF.  We don't hang up here; we only do that by
546 	 * explicit request.
547 	 */
548 	(*tp->t_linesw->l_modem)(tp, ISSET(sc->sc_ms, SYSFLG_DCD));
549 
550 	if (!ISSET(t->c_cflag, CHWFLOW))
551 		if (sc->sc_tx_stopped) {
552 			sc->sc_tx_stopped = 0;
553 			clpscom_start(tp);
554 		}
555 
556 	return 0;
557 }
558 
559 static int
560 clpscom_hwiflow(struct tty *tp, int block)
561 {
562 	/* Nothing */
563 	return 0;
564 }
565 
566 /* ARGSUSED */
567 int
568 clpscomopen(dev_t dev, int flag, int mode, struct lwp *l)
569 {
570 	struct clpscom_softc *sc;
571 	struct tty *tp;
572 	int error, s, s2;
573 
574 	sc = device_lookup_private(&clpscom_cd, COMUNIT(dev));
575 	if (sc == NULL || !ISSET(sc->sc_hwflags, COM_HW_DEV_OK))
576 		return ENXIO;
577 	if (!device_is_active(sc->sc_dev))
578 		return ENXIO;
579 
580 #ifdef KGDB
581 	/*
582 	 * If this is the kgdb port, no other use is permitted.
583 	 */
584 	if (ISSET(sc->sc_hwflags, COM_HW_KGDB))
585 		return EBUSY;
586 #endif
587 
588 	tp = sc->sc_tty;
589 
590 	if (kauth_authorize_device_tty(l->l_cred, KAUTH_DEVICE_TTY_OPEN, tp))
591 		return EBUSY;
592 
593 	s = spltty();
594 
595 	/*
596 	 * Do the following iff this is a first open.
597 	 */
598 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
599 		struct termios t;
600 
601 		tp->t_dev = dev;
602 
603 		/* Enable and turn on interrupt */
604 		CLPSCOM_WRITE_CON(sc, CLPSCOM_READ_CON(sc) | SYSCON_UARTEN);
605 
606 		/* Fetch the current modem control status, needed later. */
607 		sc->sc_ms = CLPSCOM_READ_FLG(sc) & CLPSCOM_MODEM_STATUS_MASK;
608 
609 		/*
610 		 * Initialize the termios status to the defaults.  Add in the
611 		 * sticky bits from TIOCSFLAGS.
612 		 */
613 		t.c_ispeed = 0;
614 		if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
615 			t.c_ospeed = clpscom_cnrate;
616 			t.c_cflag = clpscom_cncflag;
617 		} else {
618 			t.c_ospeed = TTYDEF_SPEED;
619 			t.c_cflag = TTYDEF_CFLAG;
620 		}
621 		if (ISSET(sc->sc_swflags, TIOCFLAG_CLOCAL))
622 			SET(t.c_cflag, CLOCAL);
623 		if (ISSET(sc->sc_swflags, TIOCFLAG_CRTSCTS))
624 			SET(t.c_cflag, CRTSCTS);
625 		if (ISSET(sc->sc_swflags, TIOCFLAG_MDMBUF))
626 			SET(t.c_cflag, MDMBUF);
627 		/* Make sure pscom_param() we do something */
628 		tp->t_ospeed = 0;
629 		clpscom_param(tp, &t);
630 		tp->t_iflag = TTYDEF_IFLAG;
631 		tp->t_oflag = TTYDEF_OFLAG;
632 		tp->t_lflag = TTYDEF_LFLAG;
633 		ttychars(tp);
634 		ttsetwater(tp);
635 
636 		s2 = splserial();
637 
638 		/* Clear the input ring. */
639 		sc->sc_rbput = sc->sc_rbget = sc->sc_rbuf;
640 		sc->sc_rbavail = CLPSCOM_RING_SIZE;
641 		clpscom_iflush(sc);
642 
643 		splx(s2);
644 	}
645 
646 	splx(s);
647 
648 	error = ttyopen(tp, COMDIALOUT(dev), ISSET(flag, O_NONBLOCK));
649 	if (error)
650 		goto bad;
651 
652 	error = (*tp->t_linesw->l_open)(dev, tp);
653 	if (error)
654 		goto bad;
655 	return 0;
656 
657 bad:
658 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
659 		/*
660 		 * We failed to open the device, and nobody else had it opened.
661 		 * Clean up the state as appropriate.
662 		 */
663 		clpscom_shutdown(sc);
664 
665 		/* Disable UART */
666 		if (!ISSET(sc->sc_hwflags, COM_HW_CONSOLE))
667 			CLPSCOM_WRITE_CON(sc,
668 			    CLPSCOM_READ_CON(sc) & ~SYSCON_UARTEN);
669 	}
670 
671 	return error;
672 }
673 
674 /* ARGSUSED */
675 int
676 clpscomclose(dev_t dev, int flag, int mode, struct lwp *l)
677 {
678 	struct clpscom_softc *sc =
679 	    device_lookup_private(&clpscom_cd, COMUNIT(dev));
680 	struct tty *tp = sc->sc_tty;
681 
682 	/* XXXX This is for cons.c. */
683 	if (!ISSET(tp->t_state, TS_ISOPEN))
684 		return 0;
685 
686 	(*tp->t_linesw->l_close)(tp, flag);
687 	ttyclose(tp);
688 
689 	if (!device_is_active(sc->sc_dev))
690 		return 0;
691 
692 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
693 		/*
694 		 * Although we got a last close, the device may still be in
695 		 * use; e.g. if this was the dialout node, and there are still
696 		 * processes waiting for carrier on the non-dialout node.
697 		 */
698 		clpscom_shutdown(sc);
699 
700 		/* Disable UART */
701 		if (!ISSET(sc->sc_hwflags, COM_HW_CONSOLE))
702 			CLPSCOM_WRITE_CON(sc,
703 			    CLPSCOM_READ_CON(sc) & ~SYSCON_UARTEN);
704 	}
705 
706 	return 0;
707 }
708 
709 int
710 clpscomread(dev_t dev, struct uio *uio, int flag)
711 {
712 	struct clpscom_softc *sc =
713 	    device_lookup_private(&clpscom_cd, COMUNIT(dev));
714 	struct tty *tp = sc->sc_tty;
715 
716 	if (!device_is_active(sc->sc_dev))
717 		return EIO;
718 
719 	return (*tp->t_linesw->l_read)(tp, uio, flag);
720 }
721 
722 int
723 clpscomwrite(dev_t dev, struct uio *uio, int flag)
724 {
725 	struct clpscom_softc *sc =
726 	    device_lookup_private(&clpscom_cd, COMUNIT(dev));
727 	struct tty *tp = sc->sc_tty;
728 
729 	if (!device_is_active(sc->sc_dev))
730 		return EIO;
731 
732 	return (*tp->t_linesw->l_write)(tp, uio, flag);
733 }
734 
735 int
736 clpscomioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l)
737 {
738 	struct clpscom_softc *sc =
739 	    device_lookup_private(&clpscom_cd, COMUNIT(dev));
740 	struct tty *tp = sc->sc_tty;
741 	int error, s;
742 
743 	if (!device_is_active(sc->sc_dev))
744 		return EIO;
745 
746 	error = (*tp->t_linesw->l_ioctl)(tp, cmd, data, flag, l);
747 	if (error != EPASSTHROUGH)
748 		return error;
749 
750 	error = ttioctl(tp, cmd, data, flag, l);
751 	if (error != EPASSTHROUGH)
752 		return error;
753 
754 	switch (cmd) {
755 	case TIOCSFLAGS:
756 		error = kauth_authorize_device_tty(l->l_cred,
757 		    KAUTH_DEVICE_TTY_PRIVSET, tp);
758 		break;
759 	default:
760 		break;
761 	}
762 	if (error)
763 		return error;
764 
765 	s = splserial();
766 	error = 0;
767 	switch (cmd) {
768 	case TIOCSBRK:
769 		clpscom_break(sc, 1);
770 		break;
771 
772 	case TIOCCBRK:
773 		clpscom_break(sc, 0);
774 		break;
775 
776 	case TIOCGFLAGS:
777 		*(int *)data = sc->sc_swflags;
778 		break;
779 
780 	case TIOCSFLAGS:
781 		sc->sc_swflags = *(int *)data;
782 		break;
783 
784 	case TIOCMGET:
785 		*(int *)data = clpscom_to_tiocm(sc);
786 		break;
787 
788 	default:
789 		error = EPASSTHROUGH;
790 		break;
791 	}
792 	splx(s);
793 	return error;
794 }
795 
796 int
797 clpscompoll(dev_t dev, int events, struct lwp *l)
798 {
799 	struct clpscom_softc *sc =
800 	    device_lookup_private(&clpscom_cd, COMUNIT(dev));
801 	struct tty *tp = sc->sc_tty;
802 
803 	if (!device_is_active(sc->sc_dev))
804 		return EIO;
805 
806 	return (*tp->t_linesw->l_poll)(tp, events, l);
807 }
808 
809 struct tty *
810 clpscomtty(dev_t dev)
811 {
812 	struct clpscom_softc *sc =
813 	    device_lookup_private(&clpscom_cd, COMUNIT(dev));
814 
815 	return sc->sc_tty;
816 }
817 
818 void
819 clpscomstop(struct tty *tp, int flag)
820 {
821 	int s;
822 
823 	s = splserial();
824 	if (ISSET(tp->t_state, TS_BUSY)) {
825 		/* Stop transmitting at the next chunk. */
826 		if (!ISSET(tp->t_state, TS_TTSTOP))
827 			SET(tp->t_state, TS_FLUSH);
828 	}
829 	splx(s);
830 }
831 
832 
833 static void
834 clpscom_iflush(struct clpscom_softc *sc)
835 {
836 	int timo;
837 
838 	timo = 50000;
839 	while ((CLPSCOM_READ_FLG(sc) & SYSFLG_URXFE) == 0
840 	    && timo--)
841 		CLPSCOM_READ(sc);
842 	if (timo == 0)
843 		printf("%s: iflush timeout\n", device_xname(sc->sc_dev));
844 }
845 
846 static void
847 clpscom_shutdown(struct clpscom_softc *sc)
848 {
849 	int s;
850 
851 	s = splserial();
852 
853 	/* Turn off all interrupts */
854 	if (sc->sc_ih[CLPSCOM_TXINT] != NULL)
855 		intr_disestablish(sc->sc_ih[CLPSCOM_TXINT]);
856 	sc->sc_ih[CLPSCOM_TXINT] = NULL;
857 	if (sc->sc_ih[CLPSCOM_RXINT] != NULL)
858 		intr_disestablish(sc->sc_ih[CLPSCOM_RXINT]);
859 	sc->sc_ih[CLPSCOM_RXINT] = NULL;
860 	if (sc->sc_ih[CLPSCOM_MSINT] != NULL)
861 		intr_disestablish(sc->sc_ih[CLPSCOM_MSINT]);
862 	sc->sc_ih[CLPSCOM_MSINT] = NULL;
863 
864 	/* Clear any break condition set with TIOCSBRK. */
865 	clpscom_break(sc, 0);
866 
867 	splx(s);
868 }
869 
870 static void
871 clpscom_break(struct clpscom_softc *sc, int onoff)
872 {
873 	int s;
874 	uint8_t ubrlcr;
875 
876 	s = splserial();
877 	ubrlcr = CLPSCOM_READ_UBRLCR(sc);
878 	if (onoff)
879 		SET(ubrlcr, UBRLCR_BREAK);
880 	else
881 		CLR(ubrlcr, UBRLCR_BREAK);
882 	CLPSCOM_WRITE_UBRLCR(sc, ubrlcr);
883 	splx(s);
884 }
885 
886 static int
887 clpscom_to_tiocm(struct clpscom_softc *sc)
888 {
889 	uint32_t combits;
890 	int ttybits = 0;
891 
892 	combits = sc->sc_ms;
893 	if (ISSET(combits, SYSFLG_DCD))
894 		SET(ttybits, TIOCM_CD);
895 	if (ISSET(combits, SYSFLG_CTS))
896 		SET(ttybits, TIOCM_CTS);
897 	if (ISSET(combits, SYSFLG_DSR))
898 		SET(ttybits, TIOCM_DSR);
899 
900 	return ttybits;
901 }
902 
903 static void
904 clpscom_rxsoft(struct clpscom_softc *sc, struct tty *tp)
905 {
906 	int code, s;
907 	u_int cc, scc;
908 	u_char sts, *get;
909 
910 	get = sc->sc_rbget;
911 	scc = cc = CLPSCOM_RING_SIZE - sc->sc_rbavail;
912 	while (cc) {
913 		code = get[0];
914 		sts = get[1];
915 		if (ISSET(sts, UARTDR_FRMERR | UARTDR_PARERR | UARTDR_OVERR)) {
916 			if (ISSET(sts, (UARTDR_FRMERR)))
917 				SET(code, TTY_FE);
918 			if (ISSET(sts, UARTDR_PARERR))
919 				SET(code, TTY_PE);
920 			if (ISSET(sts, UARTDR_OVERR))
921 				;		/* XXXXX: Overrun */
922 		}
923 		if ((*tp->t_linesw->l_rint)(code, tp) == -1) {
924 			/*
925 			 * The line discipline's buffer is out of space.
926 			 */
927 			/*
928 			 * We're either not using flow control, or the
929 			 * line discipline didn't tell us to block for
930 			 * some reason.  Either way, we have no way to
931 			 * know when there's more space available, so
932 			 * just drop the rest of the data.
933 			 */
934 			get += cc << 1;
935 			if (get >= sc->sc_rbuf + (CLPSCOM_RING_SIZE << 1))
936 				get -= (CLPSCOM_RING_SIZE << 1);
937 			cc = 0;
938 			break;
939 		}
940 		get += 2;
941 		if (get >= sc->sc_rbuf + (CLPSCOM_RING_SIZE << 1))
942 			get = sc->sc_rbuf;
943 		cc--;
944 	}
945 
946 	if (cc != scc) {
947 		sc->sc_rbget = get;
948 		s = splserial();
949 
950 		cc = sc->sc_rbavail += scc - cc;
951 		/* Buffers should be ok again, release possible block. */
952 		if (cc >= 1) {
953 			if (sc->sc_ih[CLPSCOM_RXINT] == NULL) {
954 				sc->sc_ih[CLPSCOM_RXINT] =
955 				    intr_establish(sc->sc_irq[CLPSCOM_RXINT],
956 				    IPL_SERIAL, 0, clpscom_rxintr, sc);
957 				if (sc->sc_ih[CLPSCOM_RXINT] == NULL)
958 					printf("%s: can't establish"
959 					    " rx interrupt\n",
960 					    device_xname(sc->sc_dev));
961 			}
962 			if (sc->sc_ih[CLPSCOM_MSINT] == NULL) {
963 				sc->sc_ih[CLPSCOM_MSINT] =
964 				    intr_establish(sc->sc_irq[CLPSCOM_MSINT],
965 				    IPL_SERIAL, 0, clpscom_msintr, sc);
966 				if (sc->sc_ih[CLPSCOM_MSINT] == NULL)
967 					printf("%s: can't establish"
968 					    " ms interrupt\n",
969 					    device_xname(sc->sc_dev));
970 			}
971 		}
972 		splx(s);
973 	}
974 }
975 
976 static void
977 clpscom_mssoft(struct clpscom_softc *sc, struct tty *tp)
978 {
979 	uint32_t ms, delta;
980 
981 	ms = sc->sc_ms;
982 	delta = sc->sc_ms_delta;
983 	sc->sc_ms_delta = 0;
984 
985 	if (ISSET(delta, sc->sc_ms_dcd))
986 		/*
987 		 * Inform the tty layer that carrier detect changed.
988 		 */
989 		(void) (*tp->t_linesw->l_modem)(tp, ISSET(ms, SYSFLG_DCD));
990 
991 	if (ISSET(delta, sc->sc_ms_cts)) {
992 		/* Block or unblock output according to flow control. */
993 		if (ISSET(ms, sc->sc_ms_cts)) {
994 			sc->sc_tx_stopped = 0;
995 			(*tp->t_linesw->l_start)(tp);
996 		} else
997 			sc->sc_tx_stopped = 1;
998 	}
999 }
1000 
1001 static inline uint32_t
1002 clpscom_rate2ubrlcr(int rate)
1003 {
1004 
1005 	return 230400 / rate - 1;
1006 }
1007 
1008 static uint32_t
1009 clpscom_cflag2ubrlcr(tcflag_t cflag)
1010 {
1011 	int32_t ubrlcr = 0;
1012 
1013 	switch (cflag & CSIZE) {
1014 	case CS5: SET(ubrlcr, UBRLCR_WRDLEN_5B); break;
1015 	case CS6: SET(ubrlcr, UBRLCR_WRDLEN_6B); break;
1016 	case CS7: SET(ubrlcr, UBRLCR_WRDLEN_7B); break;
1017 	case CS8: SET(ubrlcr, UBRLCR_WRDLEN_8B); break;
1018 	default:  SET(ubrlcr, UBRLCR_WRDLEN_8B); break;
1019 	}
1020 	if (cflag & CSTOPB)
1021 		SET(ubrlcr, UBRLCR_XSTOP);
1022 	if (cflag & PARENB) {
1023 		SET(ubrlcr, (UBRLCR_PRTEN | UBRLCR_EVENPRT));
1024 		if (cflag & PARODD)
1025 			CLR(ubrlcr, UBRLCR_EVENPRT);
1026 	}
1027 	return ubrlcr;
1028 }
1029 
1030 #define CLPSCOM_CNREAD() \
1031 	(*(volatile uint32_t *)(clpscom_cnaddr + PS711X_UARTDR))
1032 #define CLPSCOM_CNWRITE(val) \
1033 	(*(volatile uint8_t *)(clpscom_cnaddr + PS711X_UARTDR) = val)
1034 #define CLPSCOM_CNSTATUS() \
1035 	(*(volatile uint32_t *)(clpscom_cnaddr + PS711X_SYSFLG))
1036 
1037 static struct consdev clpscomcons = {
1038 	NULL, NULL, clpscom_cngetc, clpscom_cnputc, clpscom_cnpollc,
1039 	NULL, NULL, NULL, NODEV, CN_NORMAL
1040 };
1041 
1042 int
1043 clpscom_cnattach(vaddr_t addr, int rate, tcflag_t cflag)
1044 {
1045 
1046 	clpscom_cnaddr = addr;
1047 	clpscom_cnrate = rate;
1048 	clpscom_cncflag = cflag;
1049 	*(volatile uint32_t *)(clpscom_cnaddr + PS711X_SYSFLG) |= SYSCON_UARTEN;
1050 	*(volatile uint32_t *)(clpscom_cnaddr + PS711X_UBRLCR) =
1051 	    UBRLCR_FIFOEN |
1052 	    clpscom_cflag2ubrlcr(cflag) |
1053 	    clpscom_rate2ubrlcr(rate);
1054 
1055 	cn_tab = &clpscomcons;
1056 	cn_init_magic(&clpscom_cnm_state);
1057 	cn_set_magic("\047\001");	/* default magic is BREAK */
1058 
1059 	return 0;
1060 }
1061 
1062 /* ARGSUSED */
1063 static int
1064 clpscom_cngetc(dev_t dev)
1065 {
1066 	int s = splserial();
1067 	char ch;
1068 
1069 	while (CLPSCOM_CNSTATUS() & SYSFLG_URXFE);
1070 
1071 	ch = CLPSCOM_CNREAD();
1072 
1073 	{
1074 #ifdef DDB
1075 		extern int db_active;
1076 		if (!db_active)
1077 #endif
1078 			cn_check_magic(dev, ch, clpscom_cnm_state);
1079 	}
1080 
1081 	splx(s);
1082 	return ch;
1083 }
1084 
1085 /* ARGSUSED */
1086 static void
1087 clpscom_cnputc(dev_t dev, int c)
1088 {
1089 	int s = splserial();
1090 
1091 	while (CLPSCOM_CNSTATUS() & SYSFLG_UTXFF);
1092 
1093 	CLPSCOM_CNWRITE(c);
1094 
1095 	/* Make sure output. */
1096 	while (CLPSCOM_CNSTATUS() & SYSFLG_UBUSY);
1097 
1098 	splx(s);
1099 }
1100 
1101 /* ARGSUSED */
1102 static void
1103 clpscom_cnpollc(dev_t dev, int on)
1104 {
1105 	/* Nothing */
1106 }
1107