xref: /netbsd-src/sys/arch/arm/s3c2xx0/sscom.c (revision b7b7574d3bf8eeb51a1fa3977b59142ec6434a55)
1 /*	$NetBSD: sscom.c,v 1.44 2014/03/16 12:26:58 reinoud Exp $ */
2 
3 /*
4  * Copyright (c) 2002, 2003 Fujitsu Component Limited
5  * Copyright (c) 2002, 2003 Genetec Corporation
6  * 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. Neither the name of The Fujitsu Component Limited nor the name of
17  *    Genetec corporation may not be used to endorse or promote products
18  *    derived from this software without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY FUJITSU COMPONENT LIMITED AND GENETEC
21  * CORPORATION ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
22  * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
23  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
24  * DISCLAIMED.  IN NO EVENT SHALL FUJITSU COMPONENT LIMITED OR GENETEC
25  * CORPORATION BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
26  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
27  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
28  * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
29  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
31  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  */
34 
35 /*-
36  * Copyright (c) 1998, 1999 The NetBSD Foundation, Inc.
37  * All rights reserved.
38  *
39  * This code is derived from software contributed to The NetBSD Foundation
40  * by Charles M. Hannum.
41  *
42  * Redistribution and use in source and binary forms, with or without
43  * modification, are permitted provided that the following conditions
44  * are met:
45  * 1. Redistributions of source code must retain the above copyright
46  *    notice, this list of conditions and the following disclaimer.
47  * 2. Redistributions in binary form must reproduce the above copyright
48  *    notice, this list of conditions and the following disclaimer in the
49  *    documentation and/or other materials provided with the distribution.
50  *
51  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
52  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
53  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
54  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
55  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
56  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
57  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
58  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
59  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
60  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
61  * POSSIBILITY OF SUCH DAMAGE.
62  */
63 
64 /*
65  * Copyright (c) 1991 The Regents of the University of California.
66  * All rights reserved.
67  *
68  * Redistribution and use in source and binary forms, with or without
69  * modification, are permitted provided that the following conditions
70  * are met:
71  * 1. Redistributions of source code must retain the above copyright
72  *    notice, this list of conditions and the following disclaimer.
73  * 2. Redistributions in binary form must reproduce the above copyright
74  *    notice, this list of conditions and the following disclaimer in the
75  *    documentation and/or other materials provided with the distribution.
76  * 3. Neither the name of the University nor the names of its contributors
77  *    may be used to endorse or promote products derived from this software
78  *    without specific prior written permission.
79  *
80  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
81  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
82  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
83  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
84  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
85  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
86  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
87  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
88  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
89  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
90  * SUCH DAMAGE.
91  *
92  *	@(#)com.c	7.5 (Berkeley) 5/16/91
93  */
94 
95 /*
96  * Support integrated UARTs of Samsung S3C2800/2400X/2410X
97  * Derived from sys/dev/ic/com.c
98  */
99 
100 #include <sys/cdefs.h>
101 __KERNEL_RCSID(0, "$NetBSD: sscom.c,v 1.44 2014/03/16 12:26:58 reinoud Exp $");
102 
103 #include "opt_sscom.h"
104 #include "opt_ddb.h"
105 #include "opt_kgdb.h"
106 #include "opt_multiprocessor.h"
107 #include "opt_lockdebug.h"
108 
109 #include "rnd.h"
110 #ifdef RND_COM
111 #include <sys/rnd.h>
112 #endif
113 
114 /*
115  * Override cnmagic(9) macro before including <sys/systm.h>.
116  * We need to know if cn_check_magic triggered debugger, so set a flag.
117  * Callers of cn_check_magic must declare int cn_trapped = 0;
118  * XXX: this is *ugly*!
119  */
120 #define cn_trap()				\
121 	do {					\
122 		console_debugger();		\
123 		cn_trapped = 1;			\
124 	} while (/* CONSTCOND */ 0)
125 
126 #include <sys/param.h>
127 #include <sys/systm.h>
128 #include <sys/ioctl.h>
129 #include <sys/select.h>
130 #include <sys/tty.h>
131 #include <sys/proc.h>
132 #include <sys/conf.h>
133 #include <sys/file.h>
134 #include <sys/uio.h>
135 #include <sys/kernel.h>
136 #include <sys/syslog.h>
137 #include <sys/types.h>
138 #include <sys/device.h>
139 #include <sys/malloc.h>
140 #include <sys/timepps.h>
141 #include <sys/vnode.h>
142 #include <sys/kauth.h>
143 #include <sys/intr.h>
144 #include <sys/bus.h>
145 #include <sys/mutex.h>
146 
147 #include <arm/s3c2xx0/s3c2xx0reg.h>
148 #include <arm/s3c2xx0/sscom_var.h>
149 #include <dev/cons.h>
150 
151 dev_type_open(sscomopen);
152 dev_type_close(sscomclose);
153 dev_type_read(sscomread);
154 dev_type_write(sscomwrite);
155 dev_type_ioctl(sscomioctl);
156 dev_type_stop(sscomstop);
157 dev_type_tty(sscomtty);
158 dev_type_poll(sscompoll);
159 
160 int	sscomcngetc	(dev_t);
161 void	sscomcnputc	(dev_t, int);
162 void	sscomcnpollc	(dev_t, int);
163 
164 #define	integrate	static inline
165 void 	sscomsoft	(void *);
166 
167 integrate void sscom_rxsoft	(struct sscom_softc *, struct tty *);
168 integrate void sscom_txsoft	(struct sscom_softc *, struct tty *);
169 integrate void sscom_stsoft	(struct sscom_softc *, struct tty *);
170 integrate void sscom_schedrx	(struct sscom_softc *);
171 static void	sscom_modem(struct sscom_softc *, int);
172 static void	sscom_break(struct sscom_softc *, int);
173 static void	sscom_iflush(struct sscom_softc *);
174 static void	sscom_hwiflow(struct sscom_softc *);
175 static void	sscom_loadchannelregs(struct sscom_softc *);
176 static void	tiocm_to_sscom(struct sscom_softc *, u_long, int);
177 static int	sscom_to_tiocm(struct sscom_softc *);
178 static void	tiocm_to_sscom(struct sscom_softc *, u_long, int);
179 static int	sscom_to_tiocm(struct sscom_softc *);
180 static void	sscom_iflush(struct sscom_softc *);
181 
182 static int	sscomhwiflow(struct tty *tp, int block);
183 #if defined(KGDB) || defined(SSCOM0CONSOLE) || defined(SSCOM1CONSOLE)
184 static int	sscom_init(bus_space_tag_t, const struct sscom_uart_info *,
185 		    int, int, tcflag_t, bus_space_handle_t *);
186 #endif
187 
188 extern struct cfdriver sscom_cd;
189 
190 const struct cdevsw sscom_cdevsw = {
191 	.d_open = sscomopen,
192 	.d_close = sscomclose,
193 	.d_read = sscomread,
194 	.d_write = sscomwrite,
195 	.d_ioctl = sscomioctl,
196 	.d_stop = sscomstop,
197 	.d_tty = sscomtty,
198 	.d_poll = sscompoll,
199 	.d_mmap = nommap,
200 	.d_kqfilter = ttykqfilter,
201 	.d_flag = D_TTY
202 };
203 
204 /*
205  * Make this an option variable one can patch.
206  * But be warned:  this must be a power of 2!
207  */
208 u_int sscom_rbuf_size = SSCOM_RING_SIZE;
209 
210 /* Stop input when 3/4 of the ring is full; restart when only 1/4 is full. */
211 u_int sscom_rbuf_hiwat = (SSCOM_RING_SIZE * 1) / 4;
212 u_int sscom_rbuf_lowat = (SSCOM_RING_SIZE * 3) / 4;
213 
214 static int	sscomconsunit = -1;
215 static bus_space_tag_t sscomconstag;
216 static bus_space_handle_t sscomconsioh;
217 static int	sscomconsattached;
218 static int	sscomconsrate;
219 static tcflag_t sscomconscflag;
220 static struct cnm_state sscom_cnm_state;
221 
222 #ifdef KGDB
223 #include <sys/kgdb.h>
224 
225 static int sscom_kgdb_unit = -1;
226 static bus_space_tag_t sscom_kgdb_iot;
227 static bus_space_handle_t sscom_kgdb_ioh;
228 static int sscom_kgdb_attached;
229 
230 int	sscom_kgdb_getc (void *);
231 void	sscom_kgdb_putc (void *, int);
232 #endif /* KGDB */
233 
234 #define	SSCOMUNIT_MASK  	0x7f
235 #define	SSCOMDIALOUT_MASK	0x80
236 
237 #define	SSCOMUNIT(x)	(minor(x) & SSCOMUNIT_MASK)
238 #define	SSCOMDIALOUT(x)	(minor(x) & SSCOMDIALOUT_MASK)
239 
240 #if 0
241 #define	SSCOM_ISALIVE(sc)	((sc)->enabled != 0 && \
242 				 device_is_active(&(sc)->sc_dev))
243 #else
244 #define	SSCOM_ISALIVE(sc)	device_is_active((sc)->sc_dev)
245 #endif
246 
247 #define	BR	BUS_SPACE_BARRIER_READ
248 #define	BW	BUS_SPACE_BARRIER_WRITE
249 #define SSCOM_BARRIER(t, h, f) /* no-op */
250 
251 #if (defined(MULTIPROCESSOR) || defined(LOCKDEBUG)) && defined(SSCOM_MPLOCK)
252 
253 #define SSCOM_LOCK(sc) mutex_enter((sc)->sc_lock)
254 #define SSCOM_UNLOCK(sc) mutex_exit((sc)->sc_lock)
255 
256 #else
257 
258 #define SSCOM_LOCK(sc)
259 #define SSCOM_UNLOCK(sc)
260 
261 #endif
262 
263 #ifndef SSCOM_TOLERANCE
264 #define	SSCOM_TOLERANCE	30	/* XXX: baud rate tolerance, in 0.1% units */
265 #endif
266 
267 /* value for UCON */
268 #define UCON_RXINT_MASK	  \
269 	(UCON_RXMODE_MASK|UCON_ERRINT|UCON_TOINT|UCON_RXINT_TYPE)
270 #define UCON_RXINT_ENABLE \
271 	(UCON_RXMODE_INT|UCON_ERRINT|UCON_TOINT|UCON_RXINT_TYPE_LEVEL)
272 #define UCON_TXINT_MASK   (UCON_TXMODE_MASK|UCON_TXINT_TYPE)
273 #define UCON_TXINT_ENABLE (UCON_TXMODE_INT|UCON_TXINT_TYPE_LEVEL)
274 
275 /* we don't want tx interrupt on debug port, but it is needed to
276    have transmitter active */
277 #define UCON_DEBUGPORT	  (UCON_RXINT_ENABLE|UCON_TXINT_ENABLE)
278 
279 
280 static inline void
281 __sscom_output_chunk(struct sscom_softc *sc, int ufstat)
282 {
283 	int n, space;
284 	bus_space_tag_t iot = sc->sc_iot;
285 	bus_space_handle_t ioh = sc->sc_ioh;
286 
287 	n = sc->sc_tbc;
288 	space = 16 - ((ufstat & UFSTAT_TXCOUNT) >> UFSTAT_TXCOUNT_SHIFT);
289 
290 	if (n > space)
291 		n = space;
292 
293 	if (n > 0) {
294 		bus_space_write_multi_1(iot, ioh, SSCOM_UTXH, sc->sc_tba, n);
295 		sc->sc_tbc -= n;
296 		sc->sc_tba += n;
297 	}
298 }
299 
300 static void
301 sscom_output_chunk(struct sscom_softc *sc)
302 {
303 	int ufstat = bus_space_read_2(sc->sc_iot, sc->sc_ioh, SSCOM_UFSTAT);
304 
305 	if (!(ufstat & UFSTAT_TXFULL))
306 		__sscom_output_chunk(sc, ufstat);
307 }
308 
309 int
310 sscomspeed(long speed, long frequency)
311 {
312 #define	divrnd(n, q)	(((n)*2/(q)+1)/2)	/* divide and round off */
313 
314 	int x, err;
315 
316 	if (speed <= 0)
317 		return -1;
318 	x = divrnd(frequency / 16, speed);
319 	if (x <= 0)
320 		return -1;
321 	err = divrnd(((quad_t)frequency) * 1000 / 16, speed * x) - 1000;
322 	if (err < 0)
323 		err = -err;
324 	if (err > SSCOM_TOLERANCE)
325 		return -1;
326 	return x-1;
327 
328 #undef	divrnd
329 }
330 
331 void sscomstatus (struct sscom_softc *, const char *);
332 
333 #ifdef SSCOM_DEBUG
334 int	sscom_debug = 0;
335 
336 void
337 sscomstatus(struct sscom_softc *sc, const char *str)
338 {
339 	struct tty *tp = sc->sc_tty;
340 	int umstat = bus_space_read_1(sc->sc_iot, sc->sc_iot, SSCOM_UMSTAT);
341 	int umcon = bus_space_read_1(sc->sc_iot, sc->sc_iot, SSCOM_UMCON);
342 
343 	printf("%s: %s %sclocal  %sdcd %sts_carr_on %sdtr %stx_stopped\n",
344 	    device_xname(sc->sc_dev), str,
345 	    ISSET(tp->t_cflag, CLOCAL) ? "+" : "-",
346 	    "+",			/* DCD */
347 	    ISSET(tp->t_state, TS_CARR_ON) ? "+" : "-",
348 	    "+",			/* DTR */
349 	    sc->sc_tx_stopped ? "+" : "-");
350 
351 	printf("%s: %s %scrtscts %scts %sts_ttstop  %srts %xrx_flags\n",
352 	    device_xname(sc->sc_dev), str,
353 	    ISSET(tp->t_cflag, CRTSCTS) ? "+" : "-",
354 	    ISSET(umstat, UMSTAT_CTS) ? "+" : "-",
355 	    ISSET(tp->t_state, TS_TTSTOP) ? "+" : "-",
356 	    ISSET(umcon, UMCON_RTS) ? "+" : "-",
357 	    sc->sc_rx_flags);
358 }
359 #else
360 #define sscom_debug  0
361 #endif
362 
363 static void
364 sscom_enable_debugport(struct sscom_softc *sc)
365 {
366 	int s;
367 
368 	/* Turn on line break interrupt, set carrier. */
369 	s = splserial();
370 	SSCOM_LOCK(sc);
371 	sc->sc_ucon = UCON_DEBUGPORT;
372 	bus_space_write_2(sc->sc_iot, sc->sc_ioh, SSCOM_UCON, sc->sc_ucon);
373 	sc->sc_umcon = UMCON_RTS|UMCON_DTR;
374 	sc->sc_set_modem_control(sc);
375 	sscom_enable_rxint(sc);
376 	sscom_disable_txint(sc);
377 	SSCOM_UNLOCK(sc);
378 	splx(s);
379 }
380 
381 static void
382 sscom_set_modem_control(struct sscom_softc *sc)
383 {
384 	/* flob RTS */
385 	bus_space_write_1(sc->sc_iot, sc->sc_ioh,
386 	    SSCOM_UMCON, sc->sc_umcon & UMCON_HW_MASK);
387 	/* ignore DTR */
388 }
389 
390 static int
391 sscom_read_modem_status(struct sscom_softc *sc)
392 {
393 	int msts;
394 
395 	msts = bus_space_read_1(sc->sc_iot, sc->sc_ioh, SSCOM_UMSTAT);
396 
397 	/* DCD and DSR are always on */
398 	return (msts & UMSTAT_CTS) | MSTS_DCD | MSTS_DSR;
399 }
400 
401 void
402 sscom_attach_subr(struct sscom_softc *sc)
403 {
404 	int unit = sc->sc_unit;
405 	bus_space_tag_t iot = sc->sc_iot;
406 	bus_space_handle_t ioh = sc->sc_ioh;
407 	struct tty *tp;
408 
409 	callout_init(&sc->sc_diag_callout, 0);
410 #if (defined(MULTIPROCESSOR) || defined(LOCKDEBUG)) && defined(SSCOM_MPLOCK)
411 	sc->sc_lock = mutex_obj_alloc(MUTEX_DEFAULT, IPL_SERIAL);
412 #endif
413 
414 	sc->sc_ucon = UCON_RXINT_ENABLE|UCON_TXINT_ENABLE;
415 
416 	/*
417 	 * set default for modem control hook
418 	 */
419 	if (sc->sc_set_modem_control == NULL)
420 		sc->sc_set_modem_control = sscom_set_modem_control;
421 	if (sc->sc_read_modem_status == NULL)
422 		sc->sc_read_modem_status = sscom_read_modem_status;
423 
424 	/* Disable interrupts before configuring the device. */
425 	KASSERT(sc->sc_change_txrx_interrupts != NULL);
426 	sscom_disable_txrxint(sc);
427 
428 #ifdef KGDB
429 	/*
430 	 * Allow kgdb to "take over" this port.  If this is
431 	 * the kgdb device, it has exclusive use.
432 	 */
433 	if (unit == sscom_kgdb_unit) {
434 		SET(sc->sc_hwflags, SSCOM_HW_KGDB);
435 		sc->sc_ucon = UCON_DEBUGPORT;
436 	}
437 #endif
438 
439 	if (unit == sscomconsunit) {
440 		int timo, stat;
441 
442 		sscomconsattached = 1;
443 		sscomconstag = iot;
444 		sscomconsioh = ioh;
445 
446 		/* wait for this transmission to complete */
447 		timo = 1500000;
448 		do {
449 			stat = bus_space_read_1(iot, ioh, SSCOM_UTRSTAT);
450 		} while ((stat & UTRSTAT_TXEMPTY) == 0 && --timo > 0);
451 
452 		/* Make sure the console is always "hardwired". */
453 		SET(sc->sc_hwflags, SSCOM_HW_CONSOLE);
454 		SET(sc->sc_swflags, TIOCFLAG_SOFTCAR);
455 
456 		sc->sc_ucon = UCON_DEBUGPORT;
457 	}
458 
459 	bus_space_write_1(iot, ioh, SSCOM_UFCON,
460 #ifdef SSCOM_S3C2440
461 	    UFCON_TXTRIGGER_16|UFCON_RXTRIGGER_16|UFCON_FIFO_ENABLE|
462 #else
463 	    UFCON_TXTRIGGER_8|UFCON_RXTRIGGER_8|UFCON_FIFO_ENABLE|
464 #endif
465 	    UFCON_TXFIFO_RESET|UFCON_RXFIFO_RESET);
466 
467 	bus_space_write_1(iot, ioh, SSCOM_UCON, sc->sc_ucon);
468 
469 #ifdef KGDB
470 	if (ISSET(sc->sc_hwflags, SSCOM_HW_KGDB)) {
471 		sscom_kgdb_attached = 1;
472 		printf("%s: kgdb\n", device_xname(sc->sc_dev));
473 		sscom_enable_debugport(sc);
474 		return;
475 	}
476 #endif
477 
478 	tp = tty_alloc();
479 	tp->t_oproc = sscomstart;
480 	tp->t_param = sscomparam;
481 	tp->t_hwiflow = sscomhwiflow;
482 
483 	sc->sc_tty = tp;
484 	sc->sc_rbuf = malloc(sscom_rbuf_size << 1, M_DEVBUF, M_NOWAIT);
485 	sc->sc_rbput = sc->sc_rbget = sc->sc_rbuf;
486 	sc->sc_rbavail = sscom_rbuf_size;
487 	if (sc->sc_rbuf == NULL) {
488 		printf("%s: unable to allocate ring buffer\n",
489 		    device_xname(sc->sc_dev));
490 		return;
491 	}
492 	sc->sc_ebuf = sc->sc_rbuf + (sscom_rbuf_size << 1);
493 
494 	tty_attach(tp);
495 
496 	if (ISSET(sc->sc_hwflags, SSCOM_HW_CONSOLE)) {
497 		int maj;
498 
499 		/* locate the major number */
500 		maj = cdevsw_lookup_major(&sscom_cdevsw);
501 
502 		cn_tab->cn_dev = makedev(maj, device_unit(sc->sc_dev));
503 
504 		printf("%s: console (major=%d)\n", device_xname(sc->sc_dev), maj);
505 	}
506 
507 
508 	sc->sc_si = softint_establish(SOFTINT_SERIAL, sscomsoft, sc);
509 
510 #ifdef RND_COM
511 	rnd_attach_source(&sc->rnd_source, device_xname(sc->sc_dev),
512 			  RND_TYPE_TTY, 0);
513 #endif
514 
515 	/* if there are no enable/disable functions, assume the device
516 	   is always enabled */
517 
518 	if (ISSET(sc->sc_hwflags, SSCOM_HW_CONSOLE))
519 		sscom_enable_debugport(sc);
520 	else
521 		sscom_disable_txrxint(sc);
522 
523 	SET(sc->sc_hwflags, SSCOM_HW_DEV_OK);
524 }
525 
526 int
527 sscom_detach(device_t self, int flags)
528 {
529 	struct sscom_softc *sc = device_private(self);
530 
531 	if (sc->sc_hwflags & (SSCOM_HW_CONSOLE|SSCOM_HW_KGDB))
532 		return EBUSY;
533 
534 	return 0;
535 }
536 
537 int
538 sscom_activate(device_t self, enum devact act)
539 {
540 #ifdef notyet
541 	struct sscom_softc *sc = device_private(self);
542 #endif
543 
544 	switch (act) {
545 	case DVACT_DEACTIVATE:
546 #ifdef notyet
547 		sc->enabled = 0;
548 #endif
549 		return 0;
550 	default:
551 		return EOPNOTSUPP;
552 	}
553 }
554 
555 void
556 sscom_shutdown(struct sscom_softc *sc)
557 {
558 #ifdef notyet
559 	struct tty *tp = sc->sc_tty;
560 	int s;
561 
562 	s = splserial();
563 	SSCOM_LOCK(sc);
564 
565 	/* If we were asserting flow control, then deassert it. */
566 	SET(sc->sc_rx_flags, RX_IBUF_BLOCKED);
567 	sscom_hwiflow(sc);
568 
569 	/* Clear any break condition set with TIOCSBRK. */
570 	sscom_break(sc, 0);
571 
572 	/*
573 	 * Hang up if necessary.  Wait a bit, so the other side has time to
574 	 * notice even if we immediately open the port again.
575 	 * Avoid tsleeping above splhigh().
576 	 */
577 	if (ISSET(tp->t_cflag, HUPCL)) {
578 		sscom_modem(sc, 0);
579 		SSCOM_UNLOCK(sc);
580 		splx(s);
581 		/* XXX tsleep will only timeout */
582 		(void) tsleep(sc, TTIPRI, ttclos, hz);
583 		s = splserial();
584 		SSCOM_LOCK(sc);
585 	}
586 
587 	if (ISSET(sc->sc_hwflags, SSCOM_HW_CONSOLE))
588 		/* interrupt on break */
589 		sc->sc_ucon = UCON_DEBUGPORT;
590 	else
591 		sc->sc_ucon = 0;
592 	bus_space_write_2(sc->sc_iot, sc->sc_ioh, SSCOM_UCON, sc->sc_ucon);
593 
594 #ifdef DIAGNOSTIC
595 	if (!sc->enabled)
596 		panic("sscom_shutdown: not enabled?");
597 #endif
598 	sc->enabled = 0;
599 	SSCOM_UNLOCK(sc);
600 	splx(s);
601 #endif
602 }
603 
604 int
605 sscomopen(dev_t dev, int flag, int mode, struct lwp *l)
606 {
607 	struct sscom_softc *sc;
608 	struct tty *tp;
609 	int s, s2;
610 	int error;
611 
612 	sc = device_lookup_private(&sscom_cd, SSCOMUNIT(dev));
613 	if (sc == NULL || !ISSET(sc->sc_hwflags, SSCOM_HW_DEV_OK) ||
614 		sc->sc_rbuf == NULL)
615 		return ENXIO;
616 
617 	if (!device_is_active(sc->sc_dev))
618 		return ENXIO;
619 
620 #ifdef KGDB
621 	/*
622 	 * If this is the kgdb port, no other use is permitted.
623 	 */
624 	if (ISSET(sc->sc_hwflags, SSCOM_HW_KGDB))
625 		return EBUSY;
626 #endif
627 
628 	tp = sc->sc_tty;
629 
630 	if (kauth_authorize_device_tty(l->l_cred, KAUTH_DEVICE_TTY_OPEN, tp))
631 		return (EBUSY);
632 
633 	s = spltty();
634 
635 	/*
636 	 * Do the following iff this is a first open.
637 	 */
638 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
639 		struct termios t;
640 
641 		tp->t_dev = dev;
642 
643 		s2 = splserial();
644 		SSCOM_LOCK(sc);
645 
646 		/* Turn on interrupts. */
647 		sscom_enable_txrxint(sc);
648 
649 		/* Fetch the current modem control status, needed later. */
650 		sc->sc_msts = sc->sc_read_modem_status(sc);
651 
652 #if 0
653 		/* Clear PPS capture state on first open. */
654 		sc->sc_ppsmask = 0;
655 		sc->ppsparam.mode = 0;
656 #endif
657 
658 		SSCOM_UNLOCK(sc);
659 		splx(s2);
660 
661 		/*
662 		 * Initialize the termios status to the defaults.  Add in the
663 		 * sticky bits from TIOCSFLAGS.
664 		 */
665 		t.c_ispeed = 0;
666 		if (ISSET(sc->sc_hwflags, SSCOM_HW_CONSOLE)) {
667 			t.c_ospeed = sscomconsrate;
668 			t.c_cflag = sscomconscflag;
669 		} else {
670 			t.c_ospeed = TTYDEF_SPEED;
671 			t.c_cflag = TTYDEF_CFLAG;
672 		}
673 		if (ISSET(sc->sc_swflags, TIOCFLAG_CLOCAL))
674 			SET(t.c_cflag, CLOCAL);
675 		if (ISSET(sc->sc_swflags, TIOCFLAG_CRTSCTS))
676 			SET(t.c_cflag, CRTSCTS);
677 		if (ISSET(sc->sc_swflags, TIOCFLAG_MDMBUF))
678 			SET(t.c_cflag, MDMBUF);
679 		/* Make sure sscomparam() will do something. */
680 		tp->t_ospeed = 0;
681 		(void) sscomparam(tp, &t);
682 		tp->t_iflag = TTYDEF_IFLAG;
683 		tp->t_oflag = TTYDEF_OFLAG;
684 		tp->t_lflag = TTYDEF_LFLAG;
685 		ttychars(tp);
686 		ttsetwater(tp);
687 
688 		s2 = splserial();
689 		SSCOM_LOCK(sc);
690 
691 		/*
692 		 * Turn on DTR.  We must always do this, even if carrier is not
693 		 * present, because otherwise we'd have to use TIOCSDTR
694 		 * immediately after setting CLOCAL, which applications do not
695 		 * expect.  We always assert DTR while the device is open
696 		 * unless explicitly requested to deassert it.
697 		 */
698 		sscom_modem(sc, 1);
699 
700 		/* Clear the input ring, and unblock. */
701 		sc->sc_rbput = sc->sc_rbget = sc->sc_rbuf;
702 		sc->sc_rbavail = sscom_rbuf_size;
703 		sscom_iflush(sc);
704 		CLR(sc->sc_rx_flags, RX_ANY_BLOCK);
705 		sscom_hwiflow(sc);
706 
707 		if (sscom_debug)
708 			sscomstatus(sc, "sscomopen  ");
709 
710 		SSCOM_UNLOCK(sc);
711 		splx(s2);
712 	}
713 
714 	splx(s);
715 
716 	error = ttyopen(tp, SSCOMDIALOUT(dev), ISSET(flag, O_NONBLOCK));
717 	if (error)
718 		goto bad;
719 
720 	error = (*tp->t_linesw->l_open)(dev, tp);
721 	if (error)
722 		goto bad;
723 
724 	return 0;
725 
726 bad:
727 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
728 		/*
729 		 * We failed to open the device, and nobody else had it opened.
730 		 * Clean up the state as appropriate.
731 		 */
732 		sscom_shutdown(sc);
733 	}
734 
735 	return error;
736 }
737 
738 int
739 sscomclose(dev_t dev, int flag, int mode, struct lwp *l)
740 {
741 	struct sscom_softc *sc = device_lookup_private(&sscom_cd, SSCOMUNIT(dev));
742 	struct tty *tp = sc->sc_tty;
743 
744 	/* XXX This is for cons.c. */
745 	if (!ISSET(tp->t_state, TS_ISOPEN))
746 		return 0;
747 
748 	(*tp->t_linesw->l_close)(tp, flag);
749 	ttyclose(tp);
750 
751 	if (SSCOM_ISALIVE(sc) == 0)
752 		return 0;
753 
754 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
755 		/*
756 		 * Although we got a last close, the device may still be in
757 		 * use; e.g. if this was the dialout node, and there are still
758 		 * processes waiting for carrier on the non-dialout node.
759 		 */
760 		sscom_shutdown(sc);
761 	}
762 
763 	return 0;
764 }
765 
766 int
767 sscomread(dev_t dev, struct uio *uio, int flag)
768 {
769 	struct sscom_softc *sc = device_lookup_private(&sscom_cd, SSCOMUNIT(dev));
770 	struct tty *tp = sc->sc_tty;
771 
772 	if (SSCOM_ISALIVE(sc) == 0)
773 		return EIO;
774 
775 	return (*tp->t_linesw->l_read)(tp, uio, flag);
776 }
777 
778 int
779 sscomwrite(dev_t dev, struct uio *uio, int flag)
780 {
781 	struct sscom_softc *sc = device_lookup_private(&sscom_cd, SSCOMUNIT(dev));
782 	struct tty *tp = sc->sc_tty;
783 
784 	if (SSCOM_ISALIVE(sc) == 0)
785 		return EIO;
786 
787 	return (*tp->t_linesw->l_write)(tp, uio, flag);
788 }
789 
790 int
791 sscompoll(dev_t dev, int events, struct lwp *l)
792 {
793 	struct sscom_softc *sc = device_lookup_private(&sscom_cd, SSCOMUNIT(dev));
794 	struct tty *tp = sc->sc_tty;
795 
796 	if (SSCOM_ISALIVE(sc) == 0)
797 		return EIO;
798 
799 	return (*tp->t_linesw->l_poll)(tp, events, l);
800 }
801 
802 struct tty *
803 sscomtty(dev_t dev)
804 {
805 	struct sscom_softc *sc = device_lookup_private(&sscom_cd, SSCOMUNIT(dev));
806 	struct tty *tp = sc->sc_tty;
807 
808 	return tp;
809 }
810 
811 int
812 sscomioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l)
813 {
814 	struct sscom_softc *sc = device_lookup_private(&sscom_cd, SSCOMUNIT(dev));
815 	struct tty *tp = sc->sc_tty;
816 	int error;
817 	int s;
818 
819 	if (SSCOM_ISALIVE(sc) == 0)
820 		return EIO;
821 
822 	error = (*tp->t_linesw->l_ioctl)(tp, cmd, data, flag, l);
823 	if (error != EPASSTHROUGH)
824 		return error;
825 
826 	error = ttioctl(tp, cmd, data, flag, l);
827 	if (error != EPASSTHROUGH)
828 		return error;
829 
830 	error = 0;
831 
832 	s = splserial();
833 	SSCOM_LOCK(sc);
834 
835 	switch (cmd) {
836 	case TIOCSBRK:
837 		sscom_break(sc, 1);
838 		break;
839 
840 	case TIOCCBRK:
841 		sscom_break(sc, 0);
842 		break;
843 
844 	case TIOCSDTR:
845 		sscom_modem(sc, 1);
846 		break;
847 
848 	case TIOCCDTR:
849 		sscom_modem(sc, 0);
850 		break;
851 
852 	case TIOCGFLAGS:
853 		*(int *)data = sc->sc_swflags;
854 		break;
855 
856 	case TIOCSFLAGS:
857 		error = kauth_authorize_device_tty(l->l_cred,
858 		    KAUTH_DEVICE_TTY_PRIVSET, tp);
859 		if (error)
860 			break;
861 		sc->sc_swflags = *(int *)data;
862 		break;
863 
864 	case TIOCMSET:
865 	case TIOCMBIS:
866 	case TIOCMBIC:
867 		tiocm_to_sscom(sc, cmd, *(int *)data);
868 		break;
869 
870 	case TIOCMGET:
871 		*(int *)data = sscom_to_tiocm(sc);
872 		break;
873 
874 	default:
875 		error = EPASSTHROUGH;
876 		break;
877 	}
878 
879 	SSCOM_UNLOCK(sc);
880 	splx(s);
881 
882 	if (sscom_debug)
883 		sscomstatus(sc, "sscomioctl ");
884 
885 	return error;
886 }
887 
888 integrate void
889 sscom_schedrx(struct sscom_softc *sc)
890 {
891 
892 	sc->sc_rx_ready = 1;
893 
894 	/* Wake up the poller. */
895 	softint_schedule(sc->sc_si);
896 }
897 
898 static void
899 sscom_break(struct sscom_softc *sc, int onoff)
900 {
901 
902 	if (onoff)
903 		SET(sc->sc_ucon, UCON_SBREAK);
904 	else
905 		CLR(sc->sc_ucon, UCON_SBREAK);
906 
907 	if (!sc->sc_heldchange) {
908 		if (sc->sc_tx_busy) {
909 			sc->sc_heldtbc = sc->sc_tbc;
910 			sc->sc_tbc = 0;
911 			sc->sc_heldchange = 1;
912 		} else
913 			sscom_loadchannelregs(sc);
914 	}
915 }
916 
917 static void
918 sscom_modem(struct sscom_softc *sc, int onoff)
919 {
920 	if (onoff)
921 		SET(sc->sc_umcon, UMCON_DTR);
922 	else
923 		CLR(sc->sc_umcon, UMCON_DTR);
924 
925 	if (!sc->sc_heldchange) {
926 		if (sc->sc_tx_busy) {
927 			sc->sc_heldtbc = sc->sc_tbc;
928 			sc->sc_tbc = 0;
929 			sc->sc_heldchange = 1;
930 		} else
931 			sscom_loadchannelregs(sc);
932 	}
933 }
934 
935 static void
936 tiocm_to_sscom(struct sscom_softc *sc, u_long how, int ttybits)
937 {
938 	u_char sscombits;
939 
940 	sscombits = 0;
941 	if (ISSET(ttybits, TIOCM_DTR))
942 		sscombits = UMCON_DTR;
943 	if (ISSET(ttybits, TIOCM_RTS))
944 		SET(sscombits, UMCON_RTS);
945 
946 	switch (how) {
947 	case TIOCMBIC:
948 		CLR(sc->sc_umcon, sscombits);
949 		break;
950 
951 	case TIOCMBIS:
952 		SET(sc->sc_umcon, sscombits);
953 		break;
954 
955 	case TIOCMSET:
956 		CLR(sc->sc_umcon, UMCON_DTR);
957 		SET(sc->sc_umcon, sscombits);
958 		break;
959 	}
960 
961 	if (!sc->sc_heldchange) {
962 		if (sc->sc_tx_busy) {
963 			sc->sc_heldtbc = sc->sc_tbc;
964 			sc->sc_tbc = 0;
965 			sc->sc_heldchange = 1;
966 		} else
967 			sscom_loadchannelregs(sc);
968 	}
969 }
970 
971 static int
972 sscom_to_tiocm(struct sscom_softc *sc)
973 {
974 	u_char sscombits;
975 	int ttybits = 0;
976 
977 	sscombits = sc->sc_umcon;
978 #if 0
979 	if (ISSET(sscombits, MCR_DTR))
980 		SET(ttybits, TIOCM_DTR);
981 #endif
982 	if (ISSET(sscombits, UMCON_RTS))
983 		SET(ttybits, TIOCM_RTS);
984 
985 	sscombits = sc->sc_msts;
986 	if (ISSET(sscombits, MSTS_DCD))
987 		SET(ttybits, TIOCM_CD);
988 	if (ISSET(sscombits, MSTS_DSR))
989 		SET(ttybits, TIOCM_DSR);
990 	if (ISSET(sscombits, MSTS_CTS))
991 		SET(ttybits, TIOCM_CTS);
992 
993 	if (sc->sc_ucon != 0)
994 		SET(ttybits, TIOCM_LE);
995 
996 	return ttybits;
997 }
998 
999 static int
1000 cflag2lcr(tcflag_t cflag)
1001 {
1002 	u_char lcr = ULCON_PARITY_NONE;
1003 
1004 	switch (cflag & (PARENB|PARODD)) {
1005 	case PARENB|PARODD: lcr = ULCON_PARITY_ODD; break;
1006 	case PARENB: lcr = ULCON_PARITY_EVEN;
1007 	}
1008 
1009 	switch (ISSET(cflag, CSIZE)) {
1010 	case CS5:
1011 		SET(lcr, ULCON_LENGTH_5);
1012 		break;
1013 	case CS6:
1014 		SET(lcr, ULCON_LENGTH_6);
1015 		break;
1016 	case CS7:
1017 		SET(lcr, ULCON_LENGTH_7);
1018 		break;
1019 	case CS8:
1020 		SET(lcr, ULCON_LENGTH_8);
1021 		break;
1022 	}
1023 	if (ISSET(cflag, CSTOPB))
1024 		SET(lcr, ULCON_STOP);
1025 
1026 	return lcr;
1027 }
1028 
1029 int
1030 sscomparam(struct tty *tp, struct termios *t)
1031 {
1032 	struct sscom_softc *sc = device_lookup_private(&sscom_cd, SSCOMUNIT(tp->t_dev));
1033 	int ospeed;
1034 	u_char lcr;
1035 	int s;
1036 
1037 	if (SSCOM_ISALIVE(sc) == 0)
1038 		return EIO;
1039 
1040 	ospeed = sscomspeed(t->c_ospeed, sc->sc_frequency);
1041 
1042 	/* Check requested parameters. */
1043 	if (ospeed < 0)
1044 		return EINVAL;
1045 	if (t->c_ispeed && t->c_ispeed != t->c_ospeed)
1046 		return EINVAL;
1047 
1048 	/*
1049 	 * For the console, always force CLOCAL and !HUPCL, so that the port
1050 	 * is always active.
1051 	 */
1052 	if (ISSET(sc->sc_swflags, TIOCFLAG_SOFTCAR) ||
1053 	    ISSET(sc->sc_hwflags, SSCOM_HW_CONSOLE)) {
1054 		SET(t->c_cflag, CLOCAL);
1055 		CLR(t->c_cflag, HUPCL);
1056 	}
1057 
1058 	/*
1059 	 * If there were no changes, don't do anything.  This avoids dropping
1060 	 * input and improves performance when all we did was frob things like
1061 	 * VMIN and VTIME.
1062 	 */
1063 	if (tp->t_ospeed == t->c_ospeed &&
1064 	    tp->t_cflag == t->c_cflag)
1065 		return 0;
1066 
1067 	lcr = cflag2lcr(t->c_cflag);
1068 
1069 	s = splserial();
1070 	SSCOM_LOCK(sc);
1071 
1072 	sc->sc_ulcon = lcr;
1073 
1074 	/*
1075 	 * If we're not in a mode that assumes a connection is present, then
1076 	 * ignore carrier changes.
1077 	 */
1078 	if (ISSET(t->c_cflag, CLOCAL | MDMBUF))
1079 		sc->sc_msr_dcd = 0;
1080 	else
1081 		sc->sc_msr_dcd = MSTS_DCD;
1082 
1083 	/*
1084 	 * Set the flow control pins depending on the current flow control
1085 	 * mode.
1086 	 */
1087 	if (ISSET(t->c_cflag, CRTSCTS)) {
1088 		sc->sc_mcr_dtr = UMCON_DTR;
1089 		sc->sc_mcr_rts = UMCON_RTS;
1090 		sc->sc_msr_cts = MSTS_CTS;
1091 	}
1092 	else if (ISSET(t->c_cflag, MDMBUF)) {
1093 		/*
1094 		 * For DTR/DCD flow control, make sure we don't toggle DTR for
1095 		 * carrier detection.
1096 		 */
1097 		sc->sc_mcr_dtr = 0;
1098 		sc->sc_mcr_rts = UMCON_DTR;
1099 		sc->sc_msr_cts = MSTS_DCD;
1100 	}
1101 	else {
1102 		/*
1103 		 * If no flow control, then always set RTS.  This will make
1104 		 * the other side happy if it mistakenly thinks we're doing
1105 		 * RTS/CTS flow control.
1106 		 */
1107 		sc->sc_mcr_dtr = UMCON_DTR | UMCON_RTS;
1108 		sc->sc_mcr_rts = 0;
1109 		sc->sc_msr_cts = 0;
1110 		if (ISSET(sc->sc_umcon, UMCON_DTR))
1111 			SET(sc->sc_umcon, UMCON_RTS);
1112 		else
1113 			CLR(sc->sc_umcon, UMCON_RTS);
1114 	}
1115 	sc->sc_msr_mask = sc->sc_msr_cts | sc->sc_msr_dcd;
1116 
1117 	if (ospeed == 0)
1118 		CLR(sc->sc_umcon, sc->sc_mcr_dtr);
1119 	else
1120 		SET(sc->sc_umcon, sc->sc_mcr_dtr);
1121 
1122 	sc->sc_ubrdiv = ospeed;
1123 
1124 	/* And copy to tty. */
1125 	tp->t_ispeed = 0;
1126 	tp->t_ospeed = t->c_ospeed;
1127 	tp->t_cflag = t->c_cflag;
1128 
1129 	if (!sc->sc_heldchange) {
1130 		if (sc->sc_tx_busy) {
1131 			sc->sc_heldtbc = sc->sc_tbc;
1132 			sc->sc_tbc = 0;
1133 			sc->sc_heldchange = 1;
1134 		} else
1135 			sscom_loadchannelregs(sc);
1136 	}
1137 
1138 	if (!ISSET(t->c_cflag, CHWFLOW)) {
1139 		/* Disable the high water mark. */
1140 		sc->sc_r_hiwat = 0;
1141 		sc->sc_r_lowat = 0;
1142 		if (ISSET(sc->sc_rx_flags, RX_TTY_OVERFLOWED)) {
1143 			CLR(sc->sc_rx_flags, RX_TTY_OVERFLOWED);
1144 			sscom_schedrx(sc);
1145 		}
1146 		if (ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED|RX_IBUF_BLOCKED)) {
1147 			CLR(sc->sc_rx_flags, RX_TTY_BLOCKED|RX_IBUF_BLOCKED);
1148 			sscom_hwiflow(sc);
1149 		}
1150 	} else {
1151 		sc->sc_r_hiwat = sscom_rbuf_hiwat;
1152 		sc->sc_r_lowat = sscom_rbuf_lowat;
1153 	}
1154 
1155 	SSCOM_UNLOCK(sc);
1156 	splx(s);
1157 
1158 	/*
1159 	 * Update the tty layer's idea of the carrier bit, in case we changed
1160 	 * CLOCAL or MDMBUF.  We don't hang up here; we only do that by
1161 	 * explicit request.
1162 	 */
1163 	(void) (*tp->t_linesw->l_modem)(tp, ISSET(sc->sc_msts, MSTS_DCD));
1164 
1165 	if (sscom_debug)
1166 		sscomstatus(sc, "sscomparam ");
1167 
1168 	if (!ISSET(t->c_cflag, CHWFLOW)) {
1169 		if (sc->sc_tx_stopped) {
1170 			sc->sc_tx_stopped = 0;
1171 			sscomstart(tp);
1172 		}
1173 	}
1174 
1175 	return 0;
1176 }
1177 
1178 static void
1179 sscom_iflush(struct sscom_softc *sc)
1180 {
1181 	bus_space_tag_t iot = sc->sc_iot;
1182 	bus_space_handle_t ioh = sc->sc_ioh;
1183 	int timo;
1184 
1185 
1186 	timo = 50000;
1187 	/* flush any pending I/O */
1188 	while ( sscom_rxrdy(iot, ioh) && --timo)
1189 		(void)sscom_getc(iot,ioh);
1190 #ifdef DIAGNOSTIC
1191 	if (!timo)
1192 		printf("%s: sscom_iflush timeout\n", device_xname(sc->sc_dev));
1193 #endif
1194 }
1195 
1196 static void
1197 sscom_loadchannelregs(struct sscom_softc *sc)
1198 {
1199 	bus_space_tag_t iot = sc->sc_iot;
1200 	bus_space_handle_t ioh = sc->sc_ioh;
1201 
1202 	/* XXXXX necessary? */
1203 	sscom_iflush(sc);
1204 
1205 	bus_space_write_2(iot, ioh, SSCOM_UCON, 0);
1206 
1207 #if 0
1208 	if (ISSET(sc->sc_hwflags, COM_HW_FLOW)) {
1209 		bus_space_write_1(iot, ioh, com_lcr, LCR_EERS);
1210 		bus_space_write_1(iot, ioh, com_efr, sc->sc_efr);
1211 	}
1212 #endif
1213 
1214 	bus_space_write_2(iot, ioh, SSCOM_UBRDIV, sc->sc_ubrdiv);
1215 	bus_space_write_1(iot, ioh, SSCOM_ULCON, sc->sc_ulcon);
1216 	sc->sc_set_modem_control(sc);
1217 	bus_space_write_2(iot, ioh, SSCOM_UCON, sc->sc_ucon);
1218 }
1219 
1220 static int
1221 sscomhwiflow(struct tty *tp, int block)
1222 {
1223 	struct sscom_softc *sc = device_lookup_private(&sscom_cd, SSCOMUNIT(tp->t_dev));
1224 	int s;
1225 
1226 	if (SSCOM_ISALIVE(sc) == 0)
1227 		return 0;
1228 
1229 	if (sc->sc_mcr_rts == 0)
1230 		return 0;
1231 
1232 	s = splserial();
1233 	SSCOM_LOCK(sc);
1234 
1235 	if (block) {
1236 		if (!ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED)) {
1237 			SET(sc->sc_rx_flags, RX_TTY_BLOCKED);
1238 			sscom_hwiflow(sc);
1239 		}
1240 	} else {
1241 		if (ISSET(sc->sc_rx_flags, RX_TTY_OVERFLOWED)) {
1242 			CLR(sc->sc_rx_flags, RX_TTY_OVERFLOWED);
1243 			sscom_schedrx(sc);
1244 		}
1245 		if (ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED)) {
1246 			CLR(sc->sc_rx_flags, RX_TTY_BLOCKED);
1247 			sscom_hwiflow(sc);
1248 		}
1249 	}
1250 
1251 	SSCOM_UNLOCK(sc);
1252 	splx(s);
1253 	return 1;
1254 }
1255 
1256 /*
1257  * (un)block input via hw flowcontrol
1258  */
1259 static void
1260 sscom_hwiflow(struct sscom_softc *sc)
1261 {
1262 	if (sc->sc_mcr_rts == 0)
1263 		return;
1264 
1265 	if (ISSET(sc->sc_rx_flags, RX_ANY_BLOCK)) {
1266 		CLR(sc->sc_umcon, sc->sc_mcr_rts);
1267 		CLR(sc->sc_mcr_active, sc->sc_mcr_rts);
1268 	} else {
1269 		SET(sc->sc_umcon, sc->sc_mcr_rts);
1270 		SET(sc->sc_mcr_active, sc->sc_mcr_rts);
1271 	}
1272 	sc->sc_set_modem_control(sc);
1273 }
1274 
1275 
1276 void
1277 sscomstart(struct tty *tp)
1278 {
1279 	struct sscom_softc *sc = device_lookup_private(&sscom_cd, SSCOMUNIT(tp->t_dev));
1280 	int s;
1281 
1282 	if (SSCOM_ISALIVE(sc) == 0)
1283 		return;
1284 
1285 	s = spltty();
1286 	if (ISSET(tp->t_state, TS_BUSY | TS_TIMEOUT | TS_TTSTOP))
1287 		goto out;
1288 	if (sc->sc_tx_stopped)
1289 		goto out;
1290 	if (!ttypull(tp))
1291 		goto out;
1292 
1293 	/* Grab the first contiguous region of buffer space. */
1294 	{
1295 		u_char *tba;
1296 		int tbc;
1297 
1298 		tba = tp->t_outq.c_cf;
1299 		tbc = ndqb(&tp->t_outq, 0);
1300 
1301 		(void)splserial();
1302 		SSCOM_LOCK(sc);
1303 
1304 		sc->sc_tba = tba;
1305 		sc->sc_tbc = tbc;
1306 	}
1307 
1308 	SET(tp->t_state, TS_BUSY);
1309 	sc->sc_tx_busy = 1;
1310 
1311 	/* Output the first chunk of the contiguous buffer. */
1312 	sscom_output_chunk(sc);
1313 
1314 	/* Enable transmit completion interrupts if necessary. */
1315 	if ((sc->sc_hwflags & SSCOM_HW_TXINT) == 0)
1316 		sscom_enable_txint(sc);
1317 
1318 	SSCOM_UNLOCK(sc);
1319 out:
1320 	splx(s);
1321 	return;
1322 }
1323 
1324 /*
1325  * Stop output on a line.
1326  */
1327 void
1328 sscomstop(struct tty *tp, int flag)
1329 {
1330 	struct sscom_softc *sc = device_lookup_private(&sscom_cd, SSCOMUNIT(tp->t_dev));
1331 	int s;
1332 
1333 	s = splserial();
1334 	SSCOM_LOCK(sc);
1335 	if (ISSET(tp->t_state, TS_BUSY)) {
1336 		/* Stop transmitting at the next chunk. */
1337 		sc->sc_tbc = 0;
1338 		sc->sc_heldtbc = 0;
1339 		if (!ISSET(tp->t_state, TS_TTSTOP))
1340 			SET(tp->t_state, TS_FLUSH);
1341 	}
1342 	SSCOM_UNLOCK(sc);
1343 	splx(s);
1344 }
1345 
1346 void
1347 sscomdiag(void *arg)
1348 {
1349 	struct sscom_softc *sc = arg;
1350 	int overflows, floods;
1351 	int s;
1352 
1353 	s = splserial();
1354 	SSCOM_LOCK(sc);
1355 	overflows = sc->sc_overflows;
1356 	sc->sc_overflows = 0;
1357 	floods = sc->sc_floods;
1358 	sc->sc_floods = 0;
1359 	sc->sc_errors = 0;
1360 	SSCOM_UNLOCK(sc);
1361 	splx(s);
1362 
1363 	log(LOG_WARNING, "%s: %d silo overflow%s, %d ibuf flood%s\n",
1364 	    device_xname(sc->sc_dev),
1365 	    overflows, overflows == 1 ? "" : "s",
1366 	    floods, floods == 1 ? "" : "s");
1367 }
1368 
1369 integrate void
1370 sscom_rxsoft(struct sscom_softc *sc, struct tty *tp)
1371 {
1372 	int (*rint) (int, struct tty *) = tp->t_linesw->l_rint;
1373 	u_char *get, *end;
1374 	u_int cc, scc;
1375 	u_char rsr;
1376 	int code;
1377 	int s;
1378 
1379 	end = sc->sc_ebuf;
1380 	get = sc->sc_rbget;
1381 	scc = cc = sscom_rbuf_size - sc->sc_rbavail;
1382 
1383 	if (cc == sscom_rbuf_size) {
1384 		sc->sc_floods++;
1385 		if (sc->sc_errors++ == 0)
1386 			callout_reset(&sc->sc_diag_callout, 60 * hz,
1387 			    sscomdiag, sc);
1388 	}
1389 
1390 	while (cc) {
1391 		code = get[0];
1392 		rsr = get[1];
1393 		if (rsr) {
1394 			if (ISSET(rsr, UERSTAT_OVERRUN)) {
1395 				sc->sc_overflows++;
1396 				if (sc->sc_errors++ == 0)
1397 					callout_reset(&sc->sc_diag_callout,
1398 					    60 * hz, sscomdiag, sc);
1399 			}
1400 			if (ISSET(rsr, UERSTAT_BREAK | UERSTAT_FRAME))
1401 				SET(code, TTY_FE);
1402 			if (ISSET(rsr, UERSTAT_PARITY))
1403 				SET(code, TTY_PE);
1404 		}
1405 		if ((*rint)(code, tp) == -1) {
1406 			/*
1407 			 * The line discipline's buffer is out of space.
1408 			 */
1409 			if (!ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED)) {
1410 				/*
1411 				 * We're either not using flow control, or the
1412 				 * line discipline didn't tell us to block for
1413 				 * some reason.  Either way, we have no way to
1414 				 * know when there's more space available, so
1415 				 * just drop the rest of the data.
1416 				 */
1417 				get += cc << 1;
1418 				if (get >= end)
1419 					get -= sscom_rbuf_size << 1;
1420 				cc = 0;
1421 			} else {
1422 				/*
1423 				 * Don't schedule any more receive processing
1424 				 * until the line discipline tells us there's
1425 				 * space available (through sscomhwiflow()).
1426 				 * Leave the rest of the data in the input
1427 				 * buffer.
1428 				 */
1429 				SET(sc->sc_rx_flags, RX_TTY_OVERFLOWED);
1430 			}
1431 			break;
1432 		}
1433 		get += 2;
1434 		if (get >= end)
1435 			get = sc->sc_rbuf;
1436 		cc--;
1437 	}
1438 
1439 	if (cc != scc) {
1440 		sc->sc_rbget = get;
1441 		s = splserial();
1442 		SSCOM_LOCK(sc);
1443 
1444 		cc = sc->sc_rbavail += scc - cc;
1445 		/* Buffers should be ok again, release possible block. */
1446 		if (cc >= sc->sc_r_lowat) {
1447 			if (ISSET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED)) {
1448 				CLR(sc->sc_rx_flags, RX_IBUF_OVERFLOWED);
1449 				sscom_enable_rxint(sc);
1450 				sc->sc_ucon |= UCON_ERRINT;
1451 				bus_space_write_2(sc->sc_iot, sc->sc_ioh, SSCOM_UCON,
1452 						  sc->sc_ucon);
1453 
1454 			}
1455 			if (ISSET(sc->sc_rx_flags, RX_IBUF_BLOCKED)) {
1456 				CLR(sc->sc_rx_flags, RX_IBUF_BLOCKED);
1457 				sscom_hwiflow(sc);
1458 			}
1459 		}
1460 		SSCOM_UNLOCK(sc);
1461 		splx(s);
1462 	}
1463 }
1464 
1465 integrate void
1466 sscom_txsoft(struct sscom_softc *sc, struct tty *tp)
1467 {
1468 
1469 	CLR(tp->t_state, TS_BUSY);
1470 	if (ISSET(tp->t_state, TS_FLUSH))
1471 		CLR(tp->t_state, TS_FLUSH);
1472 	else
1473 		ndflush(&tp->t_outq, (int)(sc->sc_tba - tp->t_outq.c_cf));
1474 	(*tp->t_linesw->l_start)(tp);
1475 }
1476 
1477 integrate void
1478 sscom_stsoft(struct sscom_softc *sc, struct tty *tp)
1479 {
1480 	u_char msr, delta;
1481 	int s;
1482 
1483 	s = splserial();
1484 	SSCOM_LOCK(sc);
1485 	msr = sc->sc_msts;
1486 	delta = sc->sc_msr_delta;
1487 	sc->sc_msr_delta = 0;
1488 	SSCOM_UNLOCK(sc);
1489 	splx(s);
1490 
1491 	if (ISSET(delta, sc->sc_msr_dcd)) {
1492 		/*
1493 		 * Inform the tty layer that carrier detect changed.
1494 		 */
1495 		(void) (*tp->t_linesw->l_modem)(tp, ISSET(msr, MSTS_DCD));
1496 	}
1497 
1498 	if (ISSET(delta, sc->sc_msr_cts)) {
1499 		/* Block or unblock output according to flow control. */
1500 		if (ISSET(msr, sc->sc_msr_cts)) {
1501 			sc->sc_tx_stopped = 0;
1502 			(*tp->t_linesw->l_start)(tp);
1503 		} else {
1504 			sc->sc_tx_stopped = 1;
1505 		}
1506 	}
1507 
1508 	if (sscom_debug)
1509 		sscomstatus(sc, "sscom_stsoft");
1510 }
1511 
1512 void
1513 sscomsoft(void *arg)
1514 {
1515 	struct sscom_softc *sc = arg;
1516 	struct tty *tp;
1517 
1518 	if (SSCOM_ISALIVE(sc) == 0)
1519 		return;
1520 
1521 	{
1522 		tp = sc->sc_tty;
1523 
1524 		if (sc->sc_rx_ready) {
1525 			sc->sc_rx_ready = 0;
1526 			sscom_rxsoft(sc, tp);
1527 		}
1528 
1529 		if (sc->sc_st_check) {
1530 			sc->sc_st_check = 0;
1531 			sscom_stsoft(sc, tp);
1532 		}
1533 
1534 		if (sc->sc_tx_done) {
1535 			sc->sc_tx_done = 0;
1536 			sscom_txsoft(sc, tp);
1537 		}
1538 	}
1539 }
1540 
1541 
1542 int
1543 sscomrxintr(void *arg)
1544 {
1545 	struct sscom_softc *sc = arg;
1546 	bus_space_tag_t iot = sc->sc_iot;
1547 	bus_space_handle_t ioh = sc->sc_ioh;
1548 	u_char *put, *end;
1549 	u_int cc;
1550 
1551 	if (SSCOM_ISALIVE(sc) == 0)
1552 		return 0;
1553 
1554 	SSCOM_LOCK(sc);
1555 
1556 	end = sc->sc_ebuf;
1557 	put = sc->sc_rbput;
1558 	cc = sc->sc_rbavail;
1559 
1560 	do {
1561 		u_char	msts, delta;
1562 		u_char  uerstat;
1563 		uint16_t ufstat;
1564 
1565 		ufstat = bus_space_read_2(iot, ioh, SSCOM_UFSTAT);
1566 
1567 		/* XXX: break interrupt with no character? */
1568 
1569 		if ( (ufstat & (UFSTAT_RXCOUNT|UFSTAT_RXFULL)) &&
1570 		    !ISSET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED)) {
1571 
1572 			while (cc > 0) {
1573 				int cn_trapped = 0;
1574 
1575 				/* get status and received character.
1576 				   read status register first */
1577 				uerstat = sscom_geterr(iot, ioh);
1578 				put[0] = sscom_getc(iot, ioh);
1579 
1580 				if (ISSET(uerstat, UERSTAT_BREAK)) {
1581 					int con_trapped = 0;
1582 					cn_check_magic(sc->sc_tty->t_dev,
1583 					    CNC_BREAK, sscom_cnm_state);
1584 					if (con_trapped)
1585 						continue;
1586 #if defined(KGDB)
1587 					if (ISSET(sc->sc_hwflags,
1588 					    SSCOM_HW_KGDB)) {
1589 						kgdb_connect(1);
1590 						continue;
1591 					}
1592 #endif
1593 				}
1594 
1595 				put[1] = uerstat;
1596 				cn_check_magic(sc->sc_tty->t_dev,
1597 					       put[0], sscom_cnm_state);
1598 				if (!cn_trapped) {
1599 					put += 2;
1600 					if (put >= end)
1601 						put = sc->sc_rbuf;
1602 					cc--;
1603 				}
1604 
1605 				ufstat = bus_space_read_2(iot, ioh, SSCOM_UFSTAT);
1606 				if ( (ufstat & (UFSTAT_RXFULL|UFSTAT_RXCOUNT)) == 0 )
1607 					break;
1608 			}
1609 
1610 			/*
1611 			 * Current string of incoming characters ended because
1612 			 * no more data was available or we ran out of space.
1613 			 * Schedule a receive event if any data was received.
1614 			 * If we're out of space, turn off receive interrupts.
1615 			 */
1616 			sc->sc_rbput = put;
1617 			sc->sc_rbavail = cc;
1618 			if (!ISSET(sc->sc_rx_flags, RX_TTY_OVERFLOWED))
1619 				sc->sc_rx_ready = 1;
1620 
1621 			/*
1622 			 * See if we are in danger of overflowing a buffer. If
1623 			 * so, use hardware flow control to ease the pressure.
1624 			 */
1625 			if (!ISSET(sc->sc_rx_flags, RX_IBUF_BLOCKED) &&
1626 			    cc < sc->sc_r_hiwat) {
1627 				SET(sc->sc_rx_flags, RX_IBUF_BLOCKED);
1628 				sscom_hwiflow(sc);
1629 			}
1630 
1631 			/*
1632 			 * If we're out of space, disable receive interrupts
1633 			 * until the queue has drained a bit.
1634 			 */
1635 			if (!cc) {
1636 				SET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED);
1637 				sscom_disable_rxint(sc);
1638 				sc->sc_ucon &= ~UCON_ERRINT;
1639 				bus_space_write_2(iot, ioh, SSCOM_UCON, sc->sc_ucon);
1640 			}
1641 		}
1642 
1643 
1644 		msts = sc->sc_read_modem_status(sc);
1645 		delta = msts ^ sc->sc_msts;
1646 		sc->sc_msts = msts;
1647 
1648 #ifdef notyet
1649 		/*
1650 		 * Pulse-per-second (PSS) signals on edge of DCD?
1651 		 * Process these even if line discipline is ignoring DCD.
1652 		 */
1653 		if (delta & sc->sc_ppsmask) {
1654 			struct timeval tv;
1655 		    	if ((msr & sc->sc_ppsmask) == sc->sc_ppsassert) {
1656 				/* XXX nanotime() */
1657 				microtime(&tv);
1658 				TIMEVAL_TO_TIMESPEC(&tv,
1659 				    &sc->ppsinfo.assert_timestamp);
1660 				if (sc->ppsparam.mode & PPS_OFFSETASSERT) {
1661 					timespecadd(&sc->ppsinfo.assert_timestamp,
1662 					    &sc->ppsparam.assert_offset,
1663 						    &sc->ppsinfo.assert_timestamp);
1664 				}
1665 
1666 #ifdef PPS_SYNC
1667 				if (sc->ppsparam.mode & PPS_HARDPPSONASSERT)
1668 					hardpps(&tv, tv.tv_usec);
1669 #endif
1670 				sc->ppsinfo.assert_sequence++;
1671 				sc->ppsinfo.current_mode = sc->ppsparam.mode;
1672 
1673 			} else if ((msr & sc->sc_ppsmask) == sc->sc_ppsclear) {
1674 				/* XXX nanotime() */
1675 				microtime(&tv);
1676 				TIMEVAL_TO_TIMESPEC(&tv,
1677 				    &sc->ppsinfo.clear_timestamp);
1678 				if (sc->ppsparam.mode & PPS_OFFSETCLEAR) {
1679 					timespecadd(&sc->ppsinfo.clear_timestamp,
1680 					    &sc->ppsparam.clear_offset,
1681 					    &sc->ppsinfo.clear_timestamp);
1682 				}
1683 
1684 #ifdef PPS_SYNC
1685 				if (sc->ppsparam.mode & PPS_HARDPPSONCLEAR)
1686 					hardpps(&tv, tv.tv_usec);
1687 #endif
1688 				sc->ppsinfo.clear_sequence++;
1689 				sc->ppsinfo.current_mode = sc->ppsparam.mode;
1690 			}
1691 		}
1692 #endif
1693 
1694 		/*
1695 		 * Process normal status changes
1696 		 */
1697 		if (ISSET(delta, sc->sc_msr_mask)) {
1698 			SET(sc->sc_msr_delta, delta);
1699 
1700 			/*
1701 			 * Stop output immediately if we lose the output
1702 			 * flow control signal or carrier detect.
1703 			 */
1704 			if (ISSET(~msts, sc->sc_msr_mask)) {
1705 				sc->sc_tbc = 0;
1706 				sc->sc_heldtbc = 0;
1707 #ifdef SSCOM_DEBUG
1708 				if (sscom_debug)
1709 					sscomstatus(sc, "sscomintr  ");
1710 #endif
1711 			}
1712 
1713 			sc->sc_st_check = 1;
1714 		}
1715 
1716 		/*
1717 		 * Done handling any receive interrupts.
1718 		 */
1719 
1720 		/*
1721 		 * If we've delayed a parameter change, do it
1722 		 * now, and restart * output.
1723 		 */
1724 		if ((ufstat & UFSTAT_TXCOUNT) == 0) {
1725 			/* XXX: we should check transmitter empty also */
1726 
1727 			if (sc->sc_heldchange) {
1728 				sscom_loadchannelregs(sc);
1729 				sc->sc_heldchange = 0;
1730 				sc->sc_tbc = sc->sc_heldtbc;
1731 				sc->sc_heldtbc = 0;
1732 			}
1733 		}
1734 
1735 
1736 	} while (0);
1737 
1738 	SSCOM_UNLOCK(sc);
1739 
1740 	/* Wake up the poller. */
1741 	softint_schedule(sc->sc_si);
1742 
1743 #ifdef RND_COM
1744 	rnd_add_uint32(&sc->rnd_source, iir | rsr);
1745 #endif
1746 
1747 	return 1;
1748 }
1749 
1750 int
1751 sscomtxintr(void *arg)
1752 {
1753 	struct sscom_softc *sc = arg;
1754 	bus_space_tag_t iot = sc->sc_iot;
1755 	bus_space_handle_t ioh = sc->sc_ioh;
1756 	uint16_t ufstat;
1757 
1758 	if (SSCOM_ISALIVE(sc) == 0)
1759 		return 0;
1760 
1761 	SSCOM_LOCK(sc);
1762 
1763 	ufstat = bus_space_read_2(iot, ioh, SSCOM_UFSTAT);
1764 
1765 	/*
1766 	 * If we've delayed a parameter change, do it
1767 	 * now, and restart * output.
1768 	 */
1769 	if (sc->sc_heldchange && (ufstat & UFSTAT_TXCOUNT) == 0) {
1770 		/* XXX: we should check transmitter empty also */
1771 		sscom_loadchannelregs(sc);
1772 		sc->sc_heldchange = 0;
1773 		sc->sc_tbc = sc->sc_heldtbc;
1774 		sc->sc_heldtbc = 0;
1775 	}
1776 
1777 	/*
1778 	 * See if data can be transmitted as well. Schedule tx
1779 	 * done event if no data left and tty was marked busy.
1780 	 */
1781 	if (!ISSET(ufstat,UFSTAT_TXFULL)) {
1782 		/*
1783 		 * Output the next chunk of the contiguous
1784 		 * buffer, if any.
1785 		 */
1786 		if (sc->sc_tbc > 0) {
1787 			__sscom_output_chunk(sc, ufstat);
1788 		}
1789 		else {
1790 			/*
1791 			 * Disable transmit sscompletion
1792 			 * interrupts if necessary.
1793 			 */
1794 			if (sc->sc_hwflags & SSCOM_HW_TXINT)
1795 				sscom_disable_txint(sc);
1796 			if (sc->sc_tx_busy) {
1797 				sc->sc_tx_busy = 0;
1798 				sc->sc_tx_done = 1;
1799 			}
1800 		}
1801 	}
1802 
1803 	SSCOM_UNLOCK(sc);
1804 
1805 	/* Wake up the poller. */
1806 	softint_schedule(sc->sc_si);
1807 
1808 #ifdef RND_COM
1809 	rnd_add_uint32(&sc->rnd_source, iir | rsr);
1810 #endif
1811 
1812 	return 1;
1813 }
1814 
1815 
1816 #if defined(KGDB) || defined(SSCOM0CONSOLE) || defined(SSCOM1CONSOLE)
1817 /*
1818  * Initialize UART for use as console or KGDB line.
1819  */
1820 static int
1821 sscom_init(bus_space_tag_t iot, const struct sscom_uart_info *config,
1822     int rate, int frequency, tcflag_t cflag, bus_space_handle_t *iohp)
1823 {
1824 	bus_space_handle_t ioh;
1825 	bus_addr_t iobase = config->iobase;
1826 
1827 	if (bus_space_map(iot, iobase, SSCOM_SIZE, 0, &ioh))
1828 		return ENOMEM; /* ??? */
1829 
1830 	bus_space_write_2(iot, ioh, SSCOM_UCON, 0);
1831 	bus_space_write_1(iot, ioh, SSCOM_UFCON,
1832 #ifdef SSCOM_S3C2440
1833 	    UFCON_TXTRIGGER_16 | UFCON_RXTRIGGER_16 |
1834 #else
1835 	    UFCON_TXTRIGGER_8 | UFCON_RXTRIGGER_8 |
1836 #endif
1837 	    UFCON_TXFIFO_RESET | UFCON_RXFIFO_RESET |
1838 	    UFCON_FIFO_ENABLE );
1839 	/* tx/rx fifo reset are auto-cleared */
1840 
1841 	rate = sscomspeed(rate, frequency);
1842 	bus_space_write_2(iot, ioh, SSCOM_UBRDIV, rate);
1843 	bus_space_write_2(iot, ioh, SSCOM_ULCON, cflag2lcr(cflag));
1844 
1845 	/* enable UART */
1846 	bus_space_write_2(iot, ioh, SSCOM_UCON,
1847 	    UCON_TXMODE_INT|UCON_RXMODE_INT);
1848 	bus_space_write_2(iot, ioh, SSCOM_UMCON, UMCON_RTS);
1849 
1850 	*iohp = ioh;
1851 	return 0;
1852 }
1853 
1854 #endif
1855 
1856 #if defined(SSCOM0CONSOLE) || defined(SSCOM1CONSOLE)
1857 /*
1858  * Following are all routines needed for SSCOM to act as console
1859  */
1860 struct consdev sscomcons = {
1861 	NULL, NULL, sscomcngetc, sscomcnputc, sscomcnpollc, NULL,
1862 	NULL, NULL, NODEV, CN_NORMAL
1863 };
1864 
1865 
1866 int
1867 sscom_cnattach(bus_space_tag_t iot, const struct sscom_uart_info *config,
1868     int rate, int frequency, tcflag_t cflag)
1869 {
1870 	int res;
1871 
1872 	res = sscom_init(iot, config, rate, frequency, cflag, &sscomconsioh);
1873 	if (res)
1874 		return res;
1875 
1876 	cn_tab = &sscomcons;
1877 	cn_init_magic(&sscom_cnm_state);
1878 	cn_set_magic("\047\001"); /* default magic is BREAK */
1879 
1880 	sscomconstag = iot;
1881 	sscomconsunit = config->unit;
1882 	sscomconsrate = rate;
1883 	sscomconscflag = cflag;
1884 
1885 	return 0;
1886 }
1887 
1888 void
1889 sscom_cndetach(void)
1890 {
1891 	bus_space_unmap(sscomconstag, sscomconsioh, SSCOM_SIZE);
1892 	sscomconstag = NULL;
1893 
1894 	cn_tab = NULL;
1895 }
1896 
1897 /*
1898  * The read-ahead code is so that you can detect pending in-band
1899  * cn_magic in polled mode while doing output rather than having to
1900  * wait until the kernel decides it needs input.
1901  */
1902 
1903 #define MAX_READAHEAD	20
1904 static int sscom_readahead[MAX_READAHEAD];
1905 static int sscom_readaheadcount = 0;
1906 
1907 int
1908 sscomcngetc(dev_t dev)
1909 {
1910 	int s = splserial();
1911 	u_char __attribute__((__unused__)) stat;
1912 	u_char c;
1913 
1914 	/* got a character from reading things earlier */
1915 	if (sscom_readaheadcount > 0) {
1916 		int i;
1917 
1918 		c = sscom_readahead[0];
1919 		for (i = 1; i < sscom_readaheadcount; i++) {
1920 			sscom_readahead[i-1] = sscom_readahead[i];
1921 		}
1922 		sscom_readaheadcount--;
1923 		splx(s);
1924 		return c;
1925 	}
1926 
1927 	/* block until a character becomes available */
1928 	while (!sscom_rxrdy(sscomconstag, sscomconsioh))
1929 		;
1930 
1931 	c = sscom_getc(sscomconstag, sscomconsioh);
1932 	stat = sscom_geterr(sscomconstag, sscomconsioh);
1933 	{
1934 		int __attribute__((__unused__))cn_trapped = 0;
1935 #ifdef DDB
1936 		extern int db_active;
1937 		if (!db_active)
1938 #endif
1939 			cn_check_magic(dev, c, sscom_cnm_state);
1940 	}
1941 	splx(s);
1942 	return c;
1943 }
1944 
1945 /*
1946  * Console kernel output character routine.
1947  */
1948 void
1949 sscomcnputc(dev_t dev, int c)
1950 {
1951 	int s = splserial();
1952 	int timo;
1953 
1954 	int cin;
1955 	int __attribute__((__unused__)) stat;
1956 	if (sscom_readaheadcount < MAX_READAHEAD &&
1957 	    sscom_rxrdy(sscomconstag, sscomconsioh)) {
1958 
1959 		int __attribute__((__unused__))cn_trapped = 0;
1960 		cin = sscom_getc(sscomconstag, sscomconsioh);
1961 		stat = sscom_geterr(sscomconstag, sscomconsioh);
1962 		cn_check_magic(dev, cin, sscom_cnm_state);
1963 		sscom_readahead[sscom_readaheadcount++] = cin;
1964 	}
1965 
1966 	/* wait for any pending transmission to finish */
1967 	timo = 150000;
1968 	while (ISSET(bus_space_read_2(sscomconstag, sscomconsioh, SSCOM_UFSTAT),
1969 		   UFSTAT_TXFULL) && --timo)
1970 		continue;
1971 
1972 	bus_space_write_1(sscomconstag, sscomconsioh, SSCOM_UTXH, c);
1973 	SSCOM_BARRIER(sscomconstag, sscomconsioh, BR | BW);
1974 
1975 #if 0
1976 	/* wait for this transmission to complete */
1977 	timo = 1500000;
1978 	while (!ISSET(bus_space_read_1(sscomconstag, sscomconsioh, SSCOM_UTRSTAT),
1979 		   UTRSTAT_TXEMPTY) && --timo)
1980 		continue;
1981 #endif
1982 	splx(s);
1983 }
1984 
1985 void
1986 sscomcnpollc(dev_t dev, int on)
1987 {
1988 
1989 	sscom_readaheadcount = 0;
1990 }
1991 
1992 #endif /* SSCOM0CONSOLE||SSCOM1CONSOLE */
1993 
1994 #ifdef KGDB
1995 int
1996 sscom_kgdb_attach(bus_space_tag_t iot, const struct sscom_uart_info *config,
1997     int rate, int frequency, tcflag_t cflag)
1998 {
1999 	int res;
2000 
2001 	if (iot == sscomconstag && config->unit == sscomconsunit) {
2002 		printf( "console==kgdb_port (%d): kgdb disabled\n", sscomconsunit);
2003 		return EBUSY; /* cannot share with console */
2004 	}
2005 
2006 	res = sscom_init(iot, config, rate, frequency, cflag, &sscom_kgdb_ioh);
2007 	if (res)
2008 		return res;
2009 
2010 	kgdb_attach(sscom_kgdb_getc, sscom_kgdb_putc, NULL);
2011 	kgdb_dev = 123; /* unneeded, only to satisfy some tests */
2012 
2013 	sscom_kgdb_iot = iot;
2014 	sscom_kgdb_unit = config->unit;
2015 
2016 	return 0;
2017 }
2018 
2019 /* ARGSUSED */
2020 int
2021 sscom_kgdb_getc(void *arg)
2022 {
2023 	int c, stat;
2024 
2025 	/* block until a character becomes available */
2026 	while (!sscom_rxrdy(sscom_kgdb_iot, sscom_kgdb_ioh))
2027 		;
2028 
2029 	c = sscom_getc(sscom_kgdb_iot, sscom_kgdb_ioh);
2030 	stat = sscom_geterr(sscom_kgdb_iot, sscom_kgdb_ioh);
2031 
2032 	return c;
2033 }
2034 
2035 /* ARGSUSED */
2036 void
2037 sscom_kgdb_putc(void *arg, int c)
2038 {
2039 	int timo;
2040 
2041 	/* wait for any pending transmission to finish */
2042 	timo = 150000;
2043 	while (ISSET(bus_space_read_2(sscom_kgdb_iot, sscom_kgdb_ioh,
2044 	    SSCOM_UFSTAT), UFSTAT_TXFULL) && --timo)
2045 		continue;
2046 
2047 	bus_space_write_1(sscom_kgdb_iot, sscom_kgdb_ioh, SSCOM_UTXH, c);
2048 	SSCOM_BARRIER(sscom_kgdb_iot, sscom_kgdb_ioh, BR | BW);
2049 
2050 #if 0
2051 	/* wait for this transmission to complete */
2052 	timo = 1500000;
2053 	while (!ISSET(bus_space_read_1(sscom_kgdb_iot, sscom_kgdb_ioh,
2054 	    SSCOM_UTRSTAT), UTRSTAT_TXEMPTY) && --timo)
2055 		continue;
2056 #endif
2057 }
2058 #endif /* KGDB */
2059 
2060 /* helper function to identify the sscom ports used by
2061  console or KGDB (and not yet autoconf attached) */
2062 int
2063 sscom_is_console(bus_space_tag_t iot, int unit,
2064     bus_space_handle_t *ioh)
2065 {
2066 	bus_space_handle_t help;
2067 
2068 	if (!sscomconsattached &&
2069 	    iot == sscomconstag && unit == sscomconsunit)
2070 		help = sscomconsioh;
2071 #ifdef KGDB
2072 	else if (!sscom_kgdb_attached &&
2073 	    iot == sscom_kgdb_iot && unit == sscom_kgdb_unit)
2074 		help = sscom_kgdb_ioh;
2075 #endif
2076 	else
2077 		return 0;
2078 
2079 	if (ioh)
2080 		*ioh = help;
2081 	return 1;
2082 }
2083