xref: /netbsd-src/sys/arch/arm/s3c2xx0/sscom.c (revision 6a493d6bc668897c91594964a732d38505b70cbb)
1 /*	$NetBSD: sscom.c,v 1.39 2013/05/01 07:38:01 mlelstv 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 1.39 2013/05/01 07:38:01 mlelstv 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 
146 #include <arm/s3c2xx0/s3c2xx0reg.h>
147 #include <arm/s3c2xx0/s3c2xx0var.h>
148 #if defined(SSCOM_S3C2410) || defined(SSCOM_S3C2400) || defined(SSCOM_S3C2440)
149 #include <arm/s3c2xx0/s3c24x0reg.h>
150 #elif defined(SSCOM_S3C2800)
151 #include <arm/s3c2xx0/s3c2800reg.h>
152 #endif
153 #include <arm/s3c2xx0/sscom_var.h>
154 #include <dev/cons.h>
155 
156 dev_type_open(sscomopen);
157 dev_type_close(sscomclose);
158 dev_type_read(sscomread);
159 dev_type_write(sscomwrite);
160 dev_type_ioctl(sscomioctl);
161 dev_type_stop(sscomstop);
162 dev_type_tty(sscomtty);
163 dev_type_poll(sscompoll);
164 
165 int	sscomcngetc	(dev_t);
166 void	sscomcnputc	(dev_t, int);
167 void	sscomcnpollc	(dev_t, int);
168 
169 #define	integrate	static inline
170 void 	sscomsoft	(void *);
171 
172 integrate void sscom_rxsoft	(struct sscom_softc *, struct tty *);
173 integrate void sscom_txsoft	(struct sscom_softc *, struct tty *);
174 integrate void sscom_stsoft	(struct sscom_softc *, struct tty *);
175 integrate void sscom_schedrx	(struct sscom_softc *);
176 static void	sscom_modem(struct sscom_softc *, int);
177 static void	sscom_break(struct sscom_softc *, int);
178 static void	sscom_iflush(struct sscom_softc *);
179 static void	sscom_hwiflow(struct sscom_softc *);
180 static void	sscom_loadchannelregs(struct sscom_softc *);
181 static void	tiocm_to_sscom(struct sscom_softc *, u_long, int);
182 static int	sscom_to_tiocm(struct sscom_softc *);
183 static void	tiocm_to_sscom(struct sscom_softc *, u_long, int);
184 static int	sscom_to_tiocm(struct sscom_softc *);
185 static void	sscom_iflush(struct sscom_softc *);
186 
187 static int	sscomhwiflow(struct tty *tp, int block);
188 static int	sscom_init(bus_space_tag_t, const struct sscom_uart_info *,
189 		    int, int, tcflag_t, bus_space_handle_t *);
190 
191 extern struct cfdriver sscom_cd;
192 
193 const struct cdevsw sscom_cdevsw = {
194 	sscomopen, sscomclose, sscomread, sscomwrite, sscomioctl,
195 	sscomstop, sscomtty, sscompoll, nommap, ttykqfilter, D_TTY
196 };
197 
198 /*
199  * Make this an option variable one can patch.
200  * But be warned:  this must be a power of 2!
201  */
202 u_int sscom_rbuf_size = SSCOM_RING_SIZE;
203 
204 /* Stop input when 3/4 of the ring is full; restart when only 1/4 is full. */
205 u_int sscom_rbuf_hiwat = (SSCOM_RING_SIZE * 1) / 4;
206 u_int sscom_rbuf_lowat = (SSCOM_RING_SIZE * 3) / 4;
207 
208 static int	sscomconsunit = -1;
209 static bus_space_tag_t sscomconstag;
210 static bus_space_handle_t sscomconsioh;
211 static int	sscomconsattached;
212 static int	sscomconsrate;
213 static tcflag_t sscomconscflag;
214 static struct cnm_state sscom_cnm_state;
215 
216 #ifdef KGDB
217 #include <sys/kgdb.h>
218 
219 static int sscom_kgdb_unit = -1;
220 static bus_space_tag_t sscom_kgdb_iot;
221 static bus_space_handle_t sscom_kgdb_ioh;
222 static int sscom_kgdb_attached;
223 
224 int	sscom_kgdb_getc (void *);
225 void	sscom_kgdb_putc (void *, int);
226 #endif /* KGDB */
227 
228 #define	SSCOMUNIT_MASK  	0x7f
229 #define	SSCOMDIALOUT_MASK	0x80
230 
231 #define	SSCOMUNIT(x)	(minor(x) & SSCOMUNIT_MASK)
232 #define	SSCOMDIALOUT(x)	(minor(x) & SSCOMDIALOUT_MASK)
233 
234 #if 0
235 #define	SSCOM_ISALIVE(sc)	((sc)->enabled != 0 && \
236 				 device_is_active(&(sc)->sc_dev))
237 #else
238 #define	SSCOM_ISALIVE(sc)	device_is_active((sc)->sc_dev)
239 #endif
240 
241 #define	BR	BUS_SPACE_BARRIER_READ
242 #define	BW	BUS_SPACE_BARRIER_WRITE
243 #define SSCOM_BARRIER(t, h, f) /* no-op */
244 
245 #if (defined(MULTIPROCESSOR) || defined(LOCKDEBUG)) && defined(SSCOM_MPLOCK)
246 
247 #define SSCOM_LOCK(sc) simple_lock((sc)->sc_lock)
248 #define SSCOM_UNLOCK(sc) simple_unlock((sc)->sc_lock)
249 
250 #else
251 
252 #define SSCOM_LOCK(sc)
253 #define SSCOM_UNLOCK(sc)
254 
255 #endif
256 
257 #ifndef SSCOM_TOLERANCE
258 #define	SSCOM_TOLERANCE	30	/* XXX: baud rate tolerance, in 0.1% units */
259 #endif
260 
261 /* value for UCON */
262 #define UCON_RXINT_MASK	  \
263 	(UCON_RXMODE_MASK|UCON_ERRINT|UCON_TOINT|UCON_RXINT_TYPE)
264 #define UCON_RXINT_ENABLE \
265 	(UCON_RXMODE_INT|UCON_ERRINT|UCON_TOINT|UCON_RXINT_TYPE_LEVEL)
266 #define UCON_TXINT_MASK   (UCON_TXMODE_MASK|UCON_TXINT_TYPE)
267 #define UCON_TXINT_ENABLE (UCON_TXMODE_INT|UCON_TXINT_TYPE_LEVEL)
268 
269 /* we don't want tx interrupt on debug port, but it is needed to
270    have transmitter active */
271 #define UCON_DEBUGPORT	  (UCON_RXINT_ENABLE|UCON_TXINT_ENABLE)
272 
273 
274 static inline void
275 __sscom_output_chunk(struct sscom_softc *sc, int ufstat)
276 {
277 	int n, space;
278 	bus_space_tag_t iot = sc->sc_iot;
279 	bus_space_handle_t ioh = sc->sc_ioh;
280 
281 	n = sc->sc_tbc;
282 	space = 16 - ((ufstat & UFSTAT_TXCOUNT) >> UFSTAT_TXCOUNT_SHIFT);
283 
284 	if (n > space)
285 		n = space;
286 
287 	if (n > 0) {
288 		bus_space_write_multi_1(iot, ioh, SSCOM_UTXH, sc->sc_tba, n);
289 		sc->sc_tbc -= n;
290 		sc->sc_tba += n;
291 	}
292 }
293 
294 static void
295 sscom_output_chunk(struct sscom_softc *sc)
296 {
297 	int ufstat = bus_space_read_2(sc->sc_iot, sc->sc_ioh, SSCOM_UFSTAT);
298 
299 	if (!(ufstat & UFSTAT_TXFULL))
300 		__sscom_output_chunk(sc, ufstat);
301 }
302 
303 int
304 sscomspeed(long speed, long frequency)
305 {
306 #define	divrnd(n, q)	(((n)*2/(q)+1)/2)	/* divide and round off */
307 
308 	int x, err;
309 
310 	if (speed <= 0)
311 		return -1;
312 	x = divrnd(frequency / 16, speed);
313 	if (x <= 0)
314 		return -1;
315 	err = divrnd(((quad_t)frequency) * 1000 / 16, speed * x) - 1000;
316 	if (err < 0)
317 		err = -err;
318 	if (err > SSCOM_TOLERANCE)
319 		return -1;
320 	return x-1;
321 
322 #undef	divrnd
323 }
324 
325 void sscomstatus (struct sscom_softc *, const char *);
326 
327 #ifdef SSCOM_DEBUG
328 int	sscom_debug = 0;
329 
330 void
331 sscomstatus(struct sscom_softc *sc, const char *str)
332 {
333 	struct tty *tp = sc->sc_tty;
334 	int umstat = bus_space_read_1(sc->sc_iot, sc->sc_iot, SSCOM_UMSTAT);
335 	int umcon = bus_space_read_1(sc->sc_iot, sc->sc_iot, SSCOM_UMCON);
336 
337 	printf("%s: %s %sclocal  %sdcd %sts_carr_on %sdtr %stx_stopped\n",
338 	    device_xname(sc->sc_dev), str,
339 	    ISSET(tp->t_cflag, CLOCAL) ? "+" : "-",
340 	    "+",			/* DCD */
341 	    ISSET(tp->t_state, TS_CARR_ON) ? "+" : "-",
342 	    "+",			/* DTR */
343 	    sc->sc_tx_stopped ? "+" : "-");
344 
345 	printf("%s: %s %scrtscts %scts %sts_ttstop  %srts %xrx_flags\n",
346 	    device_xname(sc->sc_dev), str,
347 	    ISSET(tp->t_cflag, CRTSCTS) ? "+" : "-",
348 	    ISSET(umstat, UMSTAT_CTS) ? "+" : "-",
349 	    ISSET(tp->t_state, TS_TTSTOP) ? "+" : "-",
350 	    ISSET(umcon, UMCON_RTS) ? "+" : "-",
351 	    sc->sc_rx_flags);
352 }
353 #else
354 #define sscom_debug  0
355 #endif
356 
357 static void
358 sscom_enable_debugport(struct sscom_softc *sc)
359 {
360 	int s;
361 
362 	/* Turn on line break interrupt, set carrier. */
363 	s = splserial();
364 	SSCOM_LOCK(sc);
365 	sc->sc_ucon = UCON_DEBUGPORT;
366 	bus_space_write_2(sc->sc_iot, sc->sc_ioh, SSCOM_UCON, sc->sc_ucon);
367 	sc->sc_umcon = UMCON_RTS|UMCON_DTR;
368 	sc->set_modem_control(sc);
369 	sscom_enable_rxint(sc);
370 	sscom_disable_txint(sc);
371 	SSCOM_UNLOCK(sc);
372 	splx(s);
373 }
374 
375 static void
376 sscom_set_modem_control(struct sscom_softc *sc)
377 {
378 	/* flob RTS */
379 	bus_space_write_1(sc->sc_iot, sc->sc_ioh,
380 	    SSCOM_UMCON, sc->sc_umcon & UMCON_HW_MASK);
381 	/* ignore DTR */
382 }
383 
384 static int
385 sscom_read_modem_status(struct sscom_softc *sc)
386 {
387 	int msts;
388 
389 	msts = bus_space_read_1(sc->sc_iot, sc->sc_ioh, SSCOM_UMSTAT);
390 
391 	/* DCD and DSR are always on */
392 	return (msts & UMSTAT_CTS) | MSTS_DCD | MSTS_DSR;
393 }
394 
395 void
396 sscom_attach_subr(struct sscom_softc *sc)
397 {
398 	int unit = sc->sc_unit;
399 	bus_space_tag_t iot = sc->sc_iot;
400 	bus_space_handle_t ioh = sc->sc_ioh;
401 	struct tty *tp;
402 
403 	callout_init(&sc->sc_diag_callout, 0);
404 #if (defined(MULTIPROCESSOR) || defined(LOCKDEBUG)) && defined(SSCOM_MPLOCK)
405 	simple_lock_init(&sc->sc_lock);
406 #endif
407 
408 	sc->sc_ucon = UCON_RXINT_ENABLE|UCON_TXINT_ENABLE;
409 
410 	/*
411 	 * set default for modem control hook
412 	 */
413 	if (sc->set_modem_control == NULL)
414 		sc->set_modem_control = sscom_set_modem_control;
415 	if (sc->read_modem_status == NULL)
416 		sc->read_modem_status = sscom_read_modem_status;
417 
418 	/* Disable interrupts before configuring the device. */
419 	sscom_disable_txrxint(sc);
420 
421 #ifdef KGDB
422 	/*
423 	 * Allow kgdb to "take over" this port.  If this is
424 	 * the kgdb device, it has exclusive use.
425 	 */
426 	if (unit == sscom_kgdb_unit) {
427 		SET(sc->sc_hwflags, SSCOM_HW_KGDB);
428 		sc->sc_ucon = UCON_DEBUGPORT;
429 	}
430 #endif
431 
432 	if (unit == sscomconsunit) {
433 		int timo, stat;
434 
435 		sscomconsattached = 1;
436 		sscomconstag = iot;
437 		sscomconsioh = ioh;
438 
439 		/* wait for this transmission to complete */
440 		timo = 1500000;
441 		do {
442 			stat = bus_space_read_1(iot, ioh, SSCOM_UTRSTAT);
443 		} while ((stat & UTRSTAT_TXEMPTY) == 0 && --timo > 0);
444 
445 		/* Make sure the console is always "hardwired". */
446 		SET(sc->sc_hwflags, SSCOM_HW_CONSOLE);
447 		SET(sc->sc_swflags, TIOCFLAG_SOFTCAR);
448 
449 		sc->sc_ucon = UCON_DEBUGPORT;
450 	}
451 
452 	bus_space_write_1(iot, ioh, SSCOM_UFCON,
453 #ifdef SSCOM_S3C2440
454 	    UFCON_TXTRIGGER_16|UFCON_RXTRIGGER_16|UFCON_FIFO_ENABLE|
455 #else
456 	    UFCON_TXTRIGGER_8|UFCON_RXTRIGGER_8|UFCON_FIFO_ENABLE|
457 #endif
458 	    UFCON_TXFIFO_RESET|UFCON_RXFIFO_RESET);
459 
460 	bus_space_write_1(iot, ioh, SSCOM_UCON, sc->sc_ucon);
461 
462 #ifdef KGDB
463 	if (ISSET(sc->sc_hwflags, SSCOM_HW_KGDB)) {
464 		sscom_kgdb_attached = 1;
465 		printf("%s: kgdb\n", device_xname(sc->sc_dev));
466 		sscom_enable_debugport(sc);
467 		return;
468 	}
469 #endif
470 
471 	tp = tty_alloc();
472 	tp->t_oproc = sscomstart;
473 	tp->t_param = sscomparam;
474 	tp->t_hwiflow = sscomhwiflow;
475 
476 	sc->sc_tty = tp;
477 	sc->sc_rbuf = malloc(sscom_rbuf_size << 1, M_DEVBUF, M_NOWAIT);
478 	sc->sc_rbput = sc->sc_rbget = sc->sc_rbuf;
479 	sc->sc_rbavail = sscom_rbuf_size;
480 	if (sc->sc_rbuf == NULL) {
481 		printf("%s: unable to allocate ring buffer\n",
482 		    device_xname(sc->sc_dev));
483 		return;
484 	}
485 	sc->sc_ebuf = sc->sc_rbuf + (sscom_rbuf_size << 1);
486 
487 	tty_attach(tp);
488 
489 	if (ISSET(sc->sc_hwflags, SSCOM_HW_CONSOLE)) {
490 		int maj;
491 
492 		/* locate the major number */
493 		maj = cdevsw_lookup_major(&sscom_cdevsw);
494 
495 		cn_tab->cn_dev = makedev(maj, device_unit(sc->sc_dev));
496 
497 		printf("%s: console (major=%d)\n", device_xname(sc->sc_dev), maj);
498 	}
499 
500 
501 	sc->sc_si = softint_establish(SOFTINT_SERIAL, sscomsoft, sc);
502 
503 #ifdef RND_COM
504 	rnd_attach_source(&sc->rnd_source, device_xname(sc->sc_dev),
505 			  RND_TYPE_TTY, 0);
506 #endif
507 
508 	/* if there are no enable/disable functions, assume the device
509 	   is always enabled */
510 
511 	if (ISSET(sc->sc_hwflags, SSCOM_HW_CONSOLE))
512 		sscom_enable_debugport(sc);
513 	else
514 		sscom_disable_txrxint(sc);
515 
516 	SET(sc->sc_hwflags, SSCOM_HW_DEV_OK);
517 }
518 
519 int
520 sscom_detach(device_t self, int flags)
521 {
522 	struct sscom_softc *sc = device_private(self);
523 
524 	if (sc->sc_hwflags & (SSCOM_HW_CONSOLE|SSCOM_HW_KGDB))
525 		return EBUSY;
526 
527 	return 0;
528 }
529 
530 int
531 sscom_activate(device_t self, enum devact act)
532 {
533 #ifdef notyet
534 	struct sscom_softc *sc = device_private(self);
535 #endif
536 
537 	switch (act) {
538 	case DVACT_DEACTIVATE:
539 #ifdef notyet
540 		sc->enabled = 0;
541 #endif
542 		return 0;
543 	default:
544 		return EOPNOTSUPP;
545 	}
546 }
547 
548 void
549 sscom_shutdown(struct sscom_softc *sc)
550 {
551 #ifdef notyet
552 	struct tty *tp = sc->sc_tty;
553 	int s;
554 
555 	s = splserial();
556 	SSCOM_LOCK(sc);
557 
558 	/* If we were asserting flow control, then deassert it. */
559 	SET(sc->sc_rx_flags, RX_IBUF_BLOCKED);
560 	sscom_hwiflow(sc);
561 
562 	/* Clear any break condition set with TIOCSBRK. */
563 	sscom_break(sc, 0);
564 
565 	/*
566 	 * Hang up if necessary.  Wait a bit, so the other side has time to
567 	 * notice even if we immediately open the port again.
568 	 * Avoid tsleeping above splhigh().
569 	 */
570 	if (ISSET(tp->t_cflag, HUPCL)) {
571 		sscom_modem(sc, 0);
572 		SSCOM_UNLOCK(sc);
573 		splx(s);
574 		/* XXX tsleep will only timeout */
575 		(void) tsleep(sc, TTIPRI, ttclos, hz);
576 		s = splserial();
577 		SSCOM_LOCK(sc);
578 	}
579 
580 	if (ISSET(sc->sc_hwflags, SSCOM_HW_CONSOLE))
581 		/* interrupt on break */
582 		sc->sc_ucon = UCON_DEBUGPORT;
583 	else
584 		sc->sc_ucon = 0;
585 	bus_space_write_2(sc->sc_iot, sc->sc_ioh, SSCOM_UCON, sc->sc_ucon);
586 
587 #ifdef DIAGNOSTIC
588 	if (!sc->enabled)
589 		panic("sscom_shutdown: not enabled?");
590 #endif
591 	sc->enabled = 0;
592 	SSCOM_UNLOCK(sc);
593 	splx(s);
594 #endif
595 }
596 
597 int
598 sscomopen(dev_t dev, int flag, int mode, struct lwp *l)
599 {
600 	struct sscom_softc *sc;
601 	struct tty *tp;
602 	int s, s2;
603 	int error;
604 
605 	sc = device_lookup_private(&sscom_cd, SSCOMUNIT(dev));
606 	if (sc == NULL || !ISSET(sc->sc_hwflags, SSCOM_HW_DEV_OK) ||
607 		sc->sc_rbuf == NULL)
608 		return ENXIO;
609 
610 	if (!device_is_active(sc->sc_dev))
611 		return ENXIO;
612 
613 #ifdef KGDB
614 	/*
615 	 * If this is the kgdb port, no other use is permitted.
616 	 */
617 	if (ISSET(sc->sc_hwflags, SSCOM_HW_KGDB))
618 		return EBUSY;
619 #endif
620 
621 	tp = sc->sc_tty;
622 
623 	if (kauth_authorize_device_tty(l->l_cred, KAUTH_DEVICE_TTY_OPEN, tp))
624 		return (EBUSY);
625 
626 	s = spltty();
627 
628 	/*
629 	 * Do the following iff this is a first open.
630 	 */
631 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
632 		struct termios t;
633 
634 		tp->t_dev = dev;
635 
636 		s2 = splserial();
637 		SSCOM_LOCK(sc);
638 
639 		/* Turn on interrupts. */
640 		sscom_enable_txrxint(sc);
641 
642 		/* Fetch the current modem control status, needed later. */
643 		sc->sc_msts = sc->read_modem_status(sc);
644 
645 #if 0
646 		/* Clear PPS capture state on first open. */
647 		sc->sc_ppsmask = 0;
648 		sc->ppsparam.mode = 0;
649 #endif
650 
651 		SSCOM_UNLOCK(sc);
652 		splx(s2);
653 
654 		/*
655 		 * Initialize the termios status to the defaults.  Add in the
656 		 * sticky bits from TIOCSFLAGS.
657 		 */
658 		t.c_ispeed = 0;
659 		if (ISSET(sc->sc_hwflags, SSCOM_HW_CONSOLE)) {
660 			t.c_ospeed = sscomconsrate;
661 			t.c_cflag = sscomconscflag;
662 		} else {
663 			t.c_ospeed = TTYDEF_SPEED;
664 			t.c_cflag = TTYDEF_CFLAG;
665 		}
666 		if (ISSET(sc->sc_swflags, TIOCFLAG_CLOCAL))
667 			SET(t.c_cflag, CLOCAL);
668 		if (ISSET(sc->sc_swflags, TIOCFLAG_CRTSCTS))
669 			SET(t.c_cflag, CRTSCTS);
670 		if (ISSET(sc->sc_swflags, TIOCFLAG_MDMBUF))
671 			SET(t.c_cflag, MDMBUF);
672 		/* Make sure sscomparam() will do something. */
673 		tp->t_ospeed = 0;
674 		(void) sscomparam(tp, &t);
675 		tp->t_iflag = TTYDEF_IFLAG;
676 		tp->t_oflag = TTYDEF_OFLAG;
677 		tp->t_lflag = TTYDEF_LFLAG;
678 		ttychars(tp);
679 		ttsetwater(tp);
680 
681 		s2 = splserial();
682 		SSCOM_LOCK(sc);
683 
684 		/*
685 		 * Turn on DTR.  We must always do this, even if carrier is not
686 		 * present, because otherwise we'd have to use TIOCSDTR
687 		 * immediately after setting CLOCAL, which applications do not
688 		 * expect.  We always assert DTR while the device is open
689 		 * unless explicitly requested to deassert it.
690 		 */
691 		sscom_modem(sc, 1);
692 
693 		/* Clear the input ring, and unblock. */
694 		sc->sc_rbput = sc->sc_rbget = sc->sc_rbuf;
695 		sc->sc_rbavail = sscom_rbuf_size;
696 		sscom_iflush(sc);
697 		CLR(sc->sc_rx_flags, RX_ANY_BLOCK);
698 		sscom_hwiflow(sc);
699 
700 		if (sscom_debug)
701 			sscomstatus(sc, "sscomopen  ");
702 
703 		SSCOM_UNLOCK(sc);
704 		splx(s2);
705 	}
706 
707 	splx(s);
708 
709 	error = ttyopen(tp, SSCOMDIALOUT(dev), ISSET(flag, O_NONBLOCK));
710 	if (error)
711 		goto bad;
712 
713 	error = (*tp->t_linesw->l_open)(dev, tp);
714 	if (error)
715 		goto bad;
716 
717 	return 0;
718 
719 bad:
720 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
721 		/*
722 		 * We failed to open the device, and nobody else had it opened.
723 		 * Clean up the state as appropriate.
724 		 */
725 		sscom_shutdown(sc);
726 	}
727 
728 	return error;
729 }
730 
731 int
732 sscomclose(dev_t dev, int flag, int mode, struct lwp *l)
733 {
734 	struct sscom_softc *sc = device_lookup_private(&sscom_cd, SSCOMUNIT(dev));
735 	struct tty *tp = sc->sc_tty;
736 
737 	/* XXX This is for cons.c. */
738 	if (!ISSET(tp->t_state, TS_ISOPEN))
739 		return 0;
740 
741 	(*tp->t_linesw->l_close)(tp, flag);
742 	ttyclose(tp);
743 
744 	if (SSCOM_ISALIVE(sc) == 0)
745 		return 0;
746 
747 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
748 		/*
749 		 * Although we got a last close, the device may still be in
750 		 * use; e.g. if this was the dialout node, and there are still
751 		 * processes waiting for carrier on the non-dialout node.
752 		 */
753 		sscom_shutdown(sc);
754 	}
755 
756 	return 0;
757 }
758 
759 int
760 sscomread(dev_t dev, struct uio *uio, int flag)
761 {
762 	struct sscom_softc *sc = device_lookup_private(&sscom_cd, SSCOMUNIT(dev));
763 	struct tty *tp = sc->sc_tty;
764 
765 	if (SSCOM_ISALIVE(sc) == 0)
766 		return EIO;
767 
768 	return (*tp->t_linesw->l_read)(tp, uio, flag);
769 }
770 
771 int
772 sscomwrite(dev_t dev, struct uio *uio, int flag)
773 {
774 	struct sscom_softc *sc = device_lookup_private(&sscom_cd, SSCOMUNIT(dev));
775 	struct tty *tp = sc->sc_tty;
776 
777 	if (SSCOM_ISALIVE(sc) == 0)
778 		return EIO;
779 
780 	return (*tp->t_linesw->l_write)(tp, uio, flag);
781 }
782 
783 int
784 sscompoll(dev_t dev, int events, struct lwp *l)
785 {
786 	struct sscom_softc *sc = device_lookup_private(&sscom_cd, SSCOMUNIT(dev));
787 	struct tty *tp = sc->sc_tty;
788 
789 	if (SSCOM_ISALIVE(sc) == 0)
790 		return EIO;
791 
792 	return (*tp->t_linesw->l_poll)(tp, events, l);
793 }
794 
795 struct tty *
796 sscomtty(dev_t dev)
797 {
798 	struct sscom_softc *sc = device_lookup_private(&sscom_cd, SSCOMUNIT(dev));
799 	struct tty *tp = sc->sc_tty;
800 
801 	return tp;
802 }
803 
804 int
805 sscomioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l)
806 {
807 	struct sscom_softc *sc = device_lookup_private(&sscom_cd, SSCOMUNIT(dev));
808 	struct tty *tp = sc->sc_tty;
809 	int error;
810 	int s;
811 
812 	if (SSCOM_ISALIVE(sc) == 0)
813 		return EIO;
814 
815 	error = (*tp->t_linesw->l_ioctl)(tp, cmd, data, flag, l);
816 	if (error != EPASSTHROUGH)
817 		return error;
818 
819 	error = ttioctl(tp, cmd, data, flag, l);
820 	if (error != EPASSTHROUGH)
821 		return error;
822 
823 	error = 0;
824 
825 	s = splserial();
826 	SSCOM_LOCK(sc);
827 
828 	switch (cmd) {
829 	case TIOCSBRK:
830 		sscom_break(sc, 1);
831 		break;
832 
833 	case TIOCCBRK:
834 		sscom_break(sc, 0);
835 		break;
836 
837 	case TIOCSDTR:
838 		sscom_modem(sc, 1);
839 		break;
840 
841 	case TIOCCDTR:
842 		sscom_modem(sc, 0);
843 		break;
844 
845 	case TIOCGFLAGS:
846 		*(int *)data = sc->sc_swflags;
847 		break;
848 
849 	case TIOCSFLAGS:
850 		error = kauth_authorize_device_tty(l->l_cred,
851 		    KAUTH_DEVICE_TTY_PRIVSET, tp);
852 		if (error)
853 			break;
854 		sc->sc_swflags = *(int *)data;
855 		break;
856 
857 	case TIOCMSET:
858 	case TIOCMBIS:
859 	case TIOCMBIC:
860 		tiocm_to_sscom(sc, cmd, *(int *)data);
861 		break;
862 
863 	case TIOCMGET:
864 		*(int *)data = sscom_to_tiocm(sc);
865 		break;
866 
867 	default:
868 		error = EPASSTHROUGH;
869 		break;
870 	}
871 
872 	SSCOM_UNLOCK(sc);
873 	splx(s);
874 
875 	if (sscom_debug)
876 		sscomstatus(sc, "sscomioctl ");
877 
878 	return error;
879 }
880 
881 integrate void
882 sscom_schedrx(struct sscom_softc *sc)
883 {
884 
885 	sc->sc_rx_ready = 1;
886 
887 	/* Wake up the poller. */
888 	softint_schedule(sc->sc_si);
889 }
890 
891 static void
892 sscom_break(struct sscom_softc *sc, int onoff)
893 {
894 
895 	if (onoff)
896 		SET(sc->sc_ucon, UCON_SBREAK);
897 	else
898 		CLR(sc->sc_ucon, UCON_SBREAK);
899 
900 	if (!sc->sc_heldchange) {
901 		if (sc->sc_tx_busy) {
902 			sc->sc_heldtbc = sc->sc_tbc;
903 			sc->sc_tbc = 0;
904 			sc->sc_heldchange = 1;
905 		} else
906 			sscom_loadchannelregs(sc);
907 	}
908 }
909 
910 static void
911 sscom_modem(struct sscom_softc *sc, int onoff)
912 {
913 	if (onoff)
914 		SET(sc->sc_umcon, UMCON_DTR);
915 	else
916 		CLR(sc->sc_umcon, UMCON_DTR);
917 
918 	if (!sc->sc_heldchange) {
919 		if (sc->sc_tx_busy) {
920 			sc->sc_heldtbc = sc->sc_tbc;
921 			sc->sc_tbc = 0;
922 			sc->sc_heldchange = 1;
923 		} else
924 			sscom_loadchannelregs(sc);
925 	}
926 }
927 
928 static void
929 tiocm_to_sscom(struct sscom_softc *sc, u_long how, int ttybits)
930 {
931 	u_char sscombits;
932 
933 	sscombits = 0;
934 	if (ISSET(ttybits, TIOCM_DTR))
935 		sscombits = UMCON_DTR;
936 	if (ISSET(ttybits, TIOCM_RTS))
937 		SET(sscombits, UMCON_RTS);
938 
939 	switch (how) {
940 	case TIOCMBIC:
941 		CLR(sc->sc_umcon, sscombits);
942 		break;
943 
944 	case TIOCMBIS:
945 		SET(sc->sc_umcon, sscombits);
946 		break;
947 
948 	case TIOCMSET:
949 		CLR(sc->sc_umcon, UMCON_DTR);
950 		SET(sc->sc_umcon, sscombits);
951 		break;
952 	}
953 
954 	if (!sc->sc_heldchange) {
955 		if (sc->sc_tx_busy) {
956 			sc->sc_heldtbc = sc->sc_tbc;
957 			sc->sc_tbc = 0;
958 			sc->sc_heldchange = 1;
959 		} else
960 			sscom_loadchannelregs(sc);
961 	}
962 }
963 
964 static int
965 sscom_to_tiocm(struct sscom_softc *sc)
966 {
967 	u_char sscombits;
968 	int ttybits = 0;
969 
970 	sscombits = sc->sc_umcon;
971 #if 0
972 	if (ISSET(sscombits, MCR_DTR))
973 		SET(ttybits, TIOCM_DTR);
974 #endif
975 	if (ISSET(sscombits, UMCON_RTS))
976 		SET(ttybits, TIOCM_RTS);
977 
978 	sscombits = sc->sc_msts;
979 	if (ISSET(sscombits, MSTS_DCD))
980 		SET(ttybits, TIOCM_CD);
981 	if (ISSET(sscombits, MSTS_DSR))
982 		SET(ttybits, TIOCM_DSR);
983 	if (ISSET(sscombits, MSTS_CTS))
984 		SET(ttybits, TIOCM_CTS);
985 
986 	if (sc->sc_ucon != 0)
987 		SET(ttybits, TIOCM_LE);
988 
989 	return ttybits;
990 }
991 
992 static int
993 cflag2lcr(tcflag_t cflag)
994 {
995 	u_char lcr = ULCON_PARITY_NONE;
996 
997 	switch (cflag & (PARENB|PARODD)) {
998 	case PARENB|PARODD: lcr = ULCON_PARITY_ODD; break;
999 	case PARENB: lcr = ULCON_PARITY_EVEN;
1000 	}
1001 
1002 	switch (ISSET(cflag, CSIZE)) {
1003 	case CS5:
1004 		SET(lcr, ULCON_LENGTH_5);
1005 		break;
1006 	case CS6:
1007 		SET(lcr, ULCON_LENGTH_6);
1008 		break;
1009 	case CS7:
1010 		SET(lcr, ULCON_LENGTH_7);
1011 		break;
1012 	case CS8:
1013 		SET(lcr, ULCON_LENGTH_8);
1014 		break;
1015 	}
1016 	if (ISSET(cflag, CSTOPB))
1017 		SET(lcr, ULCON_STOP);
1018 
1019 	return lcr;
1020 }
1021 
1022 int
1023 sscomparam(struct tty *tp, struct termios *t)
1024 {
1025 	struct sscom_softc *sc = device_lookup_private(&sscom_cd, SSCOMUNIT(tp->t_dev));
1026 	int ospeed;
1027 	u_char lcr;
1028 	int s;
1029 
1030 	if (SSCOM_ISALIVE(sc) == 0)
1031 		return EIO;
1032 
1033 	ospeed = sscomspeed(t->c_ospeed, sc->sc_frequency);
1034 
1035 	/* Check requested parameters. */
1036 	if (ospeed < 0)
1037 		return EINVAL;
1038 	if (t->c_ispeed && t->c_ispeed != t->c_ospeed)
1039 		return EINVAL;
1040 
1041 	/*
1042 	 * For the console, always force CLOCAL and !HUPCL, so that the port
1043 	 * is always active.
1044 	 */
1045 	if (ISSET(sc->sc_swflags, TIOCFLAG_SOFTCAR) ||
1046 	    ISSET(sc->sc_hwflags, SSCOM_HW_CONSOLE)) {
1047 		SET(t->c_cflag, CLOCAL);
1048 		CLR(t->c_cflag, HUPCL);
1049 	}
1050 
1051 	/*
1052 	 * If there were no changes, don't do anything.  This avoids dropping
1053 	 * input and improves performance when all we did was frob things like
1054 	 * VMIN and VTIME.
1055 	 */
1056 	if (tp->t_ospeed == t->c_ospeed &&
1057 	    tp->t_cflag == t->c_cflag)
1058 		return 0;
1059 
1060 	lcr = cflag2lcr(t->c_cflag);
1061 
1062 	s = splserial();
1063 	SSCOM_LOCK(sc);
1064 
1065 	sc->sc_ulcon = lcr;
1066 
1067 	/*
1068 	 * If we're not in a mode that assumes a connection is present, then
1069 	 * ignore carrier changes.
1070 	 */
1071 	if (ISSET(t->c_cflag, CLOCAL | MDMBUF))
1072 		sc->sc_msr_dcd = 0;
1073 	else
1074 		sc->sc_msr_dcd = MSTS_DCD;
1075 
1076 	/*
1077 	 * Set the flow control pins depending on the current flow control
1078 	 * mode.
1079 	 */
1080 	if (ISSET(t->c_cflag, CRTSCTS)) {
1081 		sc->sc_mcr_dtr = UMCON_DTR;
1082 		sc->sc_mcr_rts = UMCON_RTS;
1083 		sc->sc_msr_cts = MSTS_CTS;
1084 	}
1085 	else if (ISSET(t->c_cflag, MDMBUF)) {
1086 		/*
1087 		 * For DTR/DCD flow control, make sure we don't toggle DTR for
1088 		 * carrier detection.
1089 		 */
1090 		sc->sc_mcr_dtr = 0;
1091 		sc->sc_mcr_rts = UMCON_DTR;
1092 		sc->sc_msr_cts = MSTS_DCD;
1093 	}
1094 	else {
1095 		/*
1096 		 * If no flow control, then always set RTS.  This will make
1097 		 * the other side happy if it mistakenly thinks we're doing
1098 		 * RTS/CTS flow control.
1099 		 */
1100 		sc->sc_mcr_dtr = UMCON_DTR | UMCON_RTS;
1101 		sc->sc_mcr_rts = 0;
1102 		sc->sc_msr_cts = 0;
1103 		if (ISSET(sc->sc_umcon, UMCON_DTR))
1104 			SET(sc->sc_umcon, UMCON_RTS);
1105 		else
1106 			CLR(sc->sc_umcon, UMCON_RTS);
1107 	}
1108 	sc->sc_msr_mask = sc->sc_msr_cts | sc->sc_msr_dcd;
1109 
1110 	if (ospeed == 0)
1111 		CLR(sc->sc_umcon, sc->sc_mcr_dtr);
1112 	else
1113 		SET(sc->sc_umcon, sc->sc_mcr_dtr);
1114 
1115 	sc->sc_ubrdiv = ospeed;
1116 
1117 	/* And copy to tty. */
1118 	tp->t_ispeed = 0;
1119 	tp->t_ospeed = t->c_ospeed;
1120 	tp->t_cflag = t->c_cflag;
1121 
1122 	if (!sc->sc_heldchange) {
1123 		if (sc->sc_tx_busy) {
1124 			sc->sc_heldtbc = sc->sc_tbc;
1125 			sc->sc_tbc = 0;
1126 			sc->sc_heldchange = 1;
1127 		} else
1128 			sscom_loadchannelregs(sc);
1129 	}
1130 
1131 	if (!ISSET(t->c_cflag, CHWFLOW)) {
1132 		/* Disable the high water mark. */
1133 		sc->sc_r_hiwat = 0;
1134 		sc->sc_r_lowat = 0;
1135 		if (ISSET(sc->sc_rx_flags, RX_TTY_OVERFLOWED)) {
1136 			CLR(sc->sc_rx_flags, RX_TTY_OVERFLOWED);
1137 			sscom_schedrx(sc);
1138 		}
1139 		if (ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED|RX_IBUF_BLOCKED)) {
1140 			CLR(sc->sc_rx_flags, RX_TTY_BLOCKED|RX_IBUF_BLOCKED);
1141 			sscom_hwiflow(sc);
1142 		}
1143 	} else {
1144 		sc->sc_r_hiwat = sscom_rbuf_hiwat;
1145 		sc->sc_r_lowat = sscom_rbuf_lowat;
1146 	}
1147 
1148 	SSCOM_UNLOCK(sc);
1149 	splx(s);
1150 
1151 	/*
1152 	 * Update the tty layer's idea of the carrier bit, in case we changed
1153 	 * CLOCAL or MDMBUF.  We don't hang up here; we only do that by
1154 	 * explicit request.
1155 	 */
1156 	(void) (*tp->t_linesw->l_modem)(tp, ISSET(sc->sc_msts, MSTS_DCD));
1157 
1158 	if (sscom_debug)
1159 		sscomstatus(sc, "sscomparam ");
1160 
1161 	if (!ISSET(t->c_cflag, CHWFLOW)) {
1162 		if (sc->sc_tx_stopped) {
1163 			sc->sc_tx_stopped = 0;
1164 			sscomstart(tp);
1165 		}
1166 	}
1167 
1168 	return 0;
1169 }
1170 
1171 static void
1172 sscom_iflush(struct sscom_softc *sc)
1173 {
1174 	bus_space_tag_t iot = sc->sc_iot;
1175 	bus_space_handle_t ioh = sc->sc_ioh;
1176 	int timo;
1177 
1178 
1179 	timo = 50000;
1180 	/* flush any pending I/O */
1181 	while ( sscom_rxrdy(iot, ioh) && --timo)
1182 		(void)sscom_getc(iot,ioh);
1183 #ifdef DIAGNOSTIC
1184 	if (!timo)
1185 		printf("%s: sscom_iflush timeout\n", device_xname(sc->sc_dev));
1186 #endif
1187 }
1188 
1189 static void
1190 sscom_loadchannelregs(struct sscom_softc *sc)
1191 {
1192 	bus_space_tag_t iot = sc->sc_iot;
1193 	bus_space_handle_t ioh = sc->sc_ioh;
1194 
1195 	/* XXXXX necessary? */
1196 	sscom_iflush(sc);
1197 
1198 	bus_space_write_2(iot, ioh, SSCOM_UCON, 0);
1199 
1200 #if 0
1201 	if (ISSET(sc->sc_hwflags, COM_HW_FLOW)) {
1202 		bus_space_write_1(iot, ioh, com_lcr, LCR_EERS);
1203 		bus_space_write_1(iot, ioh, com_efr, sc->sc_efr);
1204 	}
1205 #endif
1206 
1207 	bus_space_write_2(iot, ioh, SSCOM_UBRDIV, sc->sc_ubrdiv);
1208 	bus_space_write_1(iot, ioh, SSCOM_ULCON, sc->sc_ulcon);
1209 	sc->set_modem_control(sc);
1210 	bus_space_write_2(iot, ioh, SSCOM_UCON, sc->sc_ucon);
1211 }
1212 
1213 static int
1214 sscomhwiflow(struct tty *tp, int block)
1215 {
1216 	struct sscom_softc *sc = device_lookup_private(&sscom_cd, SSCOMUNIT(tp->t_dev));
1217 	int s;
1218 
1219 	if (SSCOM_ISALIVE(sc) == 0)
1220 		return 0;
1221 
1222 	if (sc->sc_mcr_rts == 0)
1223 		return 0;
1224 
1225 	s = splserial();
1226 	SSCOM_LOCK(sc);
1227 
1228 	if (block) {
1229 		if (!ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED)) {
1230 			SET(sc->sc_rx_flags, RX_TTY_BLOCKED);
1231 			sscom_hwiflow(sc);
1232 		}
1233 	} else {
1234 		if (ISSET(sc->sc_rx_flags, RX_TTY_OVERFLOWED)) {
1235 			CLR(sc->sc_rx_flags, RX_TTY_OVERFLOWED);
1236 			sscom_schedrx(sc);
1237 		}
1238 		if (ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED)) {
1239 			CLR(sc->sc_rx_flags, RX_TTY_BLOCKED);
1240 			sscom_hwiflow(sc);
1241 		}
1242 	}
1243 
1244 	SSCOM_UNLOCK(sc);
1245 	splx(s);
1246 	return 1;
1247 }
1248 
1249 /*
1250  * (un)block input via hw flowcontrol
1251  */
1252 static void
1253 sscom_hwiflow(struct sscom_softc *sc)
1254 {
1255 	if (sc->sc_mcr_rts == 0)
1256 		return;
1257 
1258 	if (ISSET(sc->sc_rx_flags, RX_ANY_BLOCK)) {
1259 		CLR(sc->sc_umcon, sc->sc_mcr_rts);
1260 		CLR(sc->sc_mcr_active, sc->sc_mcr_rts);
1261 	} else {
1262 		SET(sc->sc_umcon, sc->sc_mcr_rts);
1263 		SET(sc->sc_mcr_active, sc->sc_mcr_rts);
1264 	}
1265 	sc->set_modem_control(sc);
1266 }
1267 
1268 
1269 void
1270 sscomstart(struct tty *tp)
1271 {
1272 	struct sscom_softc *sc = device_lookup_private(&sscom_cd, SSCOMUNIT(tp->t_dev));
1273 	int s;
1274 
1275 	if (SSCOM_ISALIVE(sc) == 0)
1276 		return;
1277 
1278 	s = spltty();
1279 	if (ISSET(tp->t_state, TS_BUSY | TS_TIMEOUT | TS_TTSTOP))
1280 		goto out;
1281 	if (sc->sc_tx_stopped)
1282 		goto out;
1283 	if (!ttypull(tp))
1284 		goto out;
1285 
1286 	/* Grab the first contiguous region of buffer space. */
1287 	{
1288 		u_char *tba;
1289 		int tbc;
1290 
1291 		tba = tp->t_outq.c_cf;
1292 		tbc = ndqb(&tp->t_outq, 0);
1293 
1294 		(void)splserial();
1295 		SSCOM_LOCK(sc);
1296 
1297 		sc->sc_tba = tba;
1298 		sc->sc_tbc = tbc;
1299 	}
1300 
1301 	SET(tp->t_state, TS_BUSY);
1302 	sc->sc_tx_busy = 1;
1303 
1304 	/* Output the first chunk of the contiguous buffer. */
1305 	sscom_output_chunk(sc);
1306 
1307 	/* Enable transmit completion interrupts if necessary. */
1308 	if ((sc->sc_hwflags & SSCOM_HW_TXINT) == 0)
1309 		sscom_enable_txint(sc);
1310 
1311 	SSCOM_UNLOCK(sc);
1312 out:
1313 	splx(s);
1314 	return;
1315 }
1316 
1317 /*
1318  * Stop output on a line.
1319  */
1320 void
1321 sscomstop(struct tty *tp, int flag)
1322 {
1323 	struct sscom_softc *sc = device_lookup_private(&sscom_cd, SSCOMUNIT(tp->t_dev));
1324 	int s;
1325 
1326 	s = splserial();
1327 	SSCOM_LOCK(sc);
1328 	if (ISSET(tp->t_state, TS_BUSY)) {
1329 		/* Stop transmitting at the next chunk. */
1330 		sc->sc_tbc = 0;
1331 		sc->sc_heldtbc = 0;
1332 		if (!ISSET(tp->t_state, TS_TTSTOP))
1333 			SET(tp->t_state, TS_FLUSH);
1334 	}
1335 	SSCOM_UNLOCK(sc);
1336 	splx(s);
1337 }
1338 
1339 void
1340 sscomdiag(void *arg)
1341 {
1342 	struct sscom_softc *sc = arg;
1343 	int overflows, floods;
1344 	int s;
1345 
1346 	s = splserial();
1347 	SSCOM_LOCK(sc);
1348 	overflows = sc->sc_overflows;
1349 	sc->sc_overflows = 0;
1350 	floods = sc->sc_floods;
1351 	sc->sc_floods = 0;
1352 	sc->sc_errors = 0;
1353 	SSCOM_UNLOCK(sc);
1354 	splx(s);
1355 
1356 	log(LOG_WARNING, "%s: %d silo overflow%s, %d ibuf flood%s\n",
1357 	    device_xname(sc->sc_dev),
1358 	    overflows, overflows == 1 ? "" : "s",
1359 	    floods, floods == 1 ? "" : "s");
1360 }
1361 
1362 integrate void
1363 sscom_rxsoft(struct sscom_softc *sc, struct tty *tp)
1364 {
1365 	int (*rint) (int, struct tty *) = tp->t_linesw->l_rint;
1366 	u_char *get, *end;
1367 	u_int cc, scc;
1368 	u_char rsr;
1369 	int code;
1370 	int s;
1371 
1372 	end = sc->sc_ebuf;
1373 	get = sc->sc_rbget;
1374 	scc = cc = sscom_rbuf_size - sc->sc_rbavail;
1375 
1376 	if (cc == sscom_rbuf_size) {
1377 		sc->sc_floods++;
1378 		if (sc->sc_errors++ == 0)
1379 			callout_reset(&sc->sc_diag_callout, 60 * hz,
1380 			    sscomdiag, sc);
1381 	}
1382 
1383 	while (cc) {
1384 		code = get[0];
1385 		rsr = get[1];
1386 		if (rsr) {
1387 			if (ISSET(rsr, UERSTAT_OVERRUN)) {
1388 				sc->sc_overflows++;
1389 				if (sc->sc_errors++ == 0)
1390 					callout_reset(&sc->sc_diag_callout,
1391 					    60 * hz, sscomdiag, sc);
1392 			}
1393 			if (ISSET(rsr, UERSTAT_BREAK | UERSTAT_FRAME))
1394 				SET(code, TTY_FE);
1395 			if (ISSET(rsr, UERSTAT_PARITY))
1396 				SET(code, TTY_PE);
1397 		}
1398 		if ((*rint)(code, tp) == -1) {
1399 			/*
1400 			 * The line discipline's buffer is out of space.
1401 			 */
1402 			if (!ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED)) {
1403 				/*
1404 				 * We're either not using flow control, or the
1405 				 * line discipline didn't tell us to block for
1406 				 * some reason.  Either way, we have no way to
1407 				 * know when there's more space available, so
1408 				 * just drop the rest of the data.
1409 				 */
1410 				get += cc << 1;
1411 				if (get >= end)
1412 					get -= sscom_rbuf_size << 1;
1413 				cc = 0;
1414 			} else {
1415 				/*
1416 				 * Don't schedule any more receive processing
1417 				 * until the line discipline tells us there's
1418 				 * space available (through sscomhwiflow()).
1419 				 * Leave the rest of the data in the input
1420 				 * buffer.
1421 				 */
1422 				SET(sc->sc_rx_flags, RX_TTY_OVERFLOWED);
1423 			}
1424 			break;
1425 		}
1426 		get += 2;
1427 		if (get >= end)
1428 			get = sc->sc_rbuf;
1429 		cc--;
1430 	}
1431 
1432 	if (cc != scc) {
1433 		sc->sc_rbget = get;
1434 		s = splserial();
1435 		SSCOM_LOCK(sc);
1436 
1437 		cc = sc->sc_rbavail += scc - cc;
1438 		/* Buffers should be ok again, release possible block. */
1439 		if (cc >= sc->sc_r_lowat) {
1440 			if (ISSET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED)) {
1441 				CLR(sc->sc_rx_flags, RX_IBUF_OVERFLOWED);
1442 				sscom_enable_rxint(sc);
1443 				sc->sc_ucon |= UCON_ERRINT;
1444 				bus_space_write_2(sc->sc_iot, sc->sc_ioh, SSCOM_UCON,
1445 						  sc->sc_ucon);
1446 
1447 			}
1448 			if (ISSET(sc->sc_rx_flags, RX_IBUF_BLOCKED)) {
1449 				CLR(sc->sc_rx_flags, RX_IBUF_BLOCKED);
1450 				sscom_hwiflow(sc);
1451 			}
1452 		}
1453 		SSCOM_UNLOCK(sc);
1454 		splx(s);
1455 	}
1456 }
1457 
1458 integrate void
1459 sscom_txsoft(struct sscom_softc *sc, struct tty *tp)
1460 {
1461 
1462 	CLR(tp->t_state, TS_BUSY);
1463 	if (ISSET(tp->t_state, TS_FLUSH))
1464 		CLR(tp->t_state, TS_FLUSH);
1465 	else
1466 		ndflush(&tp->t_outq, (int)(sc->sc_tba - tp->t_outq.c_cf));
1467 	(*tp->t_linesw->l_start)(tp);
1468 }
1469 
1470 integrate void
1471 sscom_stsoft(struct sscom_softc *sc, struct tty *tp)
1472 {
1473 	u_char msr, delta;
1474 	int s;
1475 
1476 	s = splserial();
1477 	SSCOM_LOCK(sc);
1478 	msr = sc->sc_msts;
1479 	delta = sc->sc_msr_delta;
1480 	sc->sc_msr_delta = 0;
1481 	SSCOM_UNLOCK(sc);
1482 	splx(s);
1483 
1484 	if (ISSET(delta, sc->sc_msr_dcd)) {
1485 		/*
1486 		 * Inform the tty layer that carrier detect changed.
1487 		 */
1488 		(void) (*tp->t_linesw->l_modem)(tp, ISSET(msr, MSTS_DCD));
1489 	}
1490 
1491 	if (ISSET(delta, sc->sc_msr_cts)) {
1492 		/* Block or unblock output according to flow control. */
1493 		if (ISSET(msr, sc->sc_msr_cts)) {
1494 			sc->sc_tx_stopped = 0;
1495 			(*tp->t_linesw->l_start)(tp);
1496 		} else {
1497 			sc->sc_tx_stopped = 1;
1498 		}
1499 	}
1500 
1501 	if (sscom_debug)
1502 		sscomstatus(sc, "sscom_stsoft");
1503 }
1504 
1505 void
1506 sscomsoft(void *arg)
1507 {
1508 	struct sscom_softc *sc = arg;
1509 	struct tty *tp;
1510 
1511 	if (SSCOM_ISALIVE(sc) == 0)
1512 		return;
1513 
1514 	{
1515 		tp = sc->sc_tty;
1516 
1517 		if (sc->sc_rx_ready) {
1518 			sc->sc_rx_ready = 0;
1519 			sscom_rxsoft(sc, tp);
1520 		}
1521 
1522 		if (sc->sc_st_check) {
1523 			sc->sc_st_check = 0;
1524 			sscom_stsoft(sc, tp);
1525 		}
1526 
1527 		if (sc->sc_tx_done) {
1528 			sc->sc_tx_done = 0;
1529 			sscom_txsoft(sc, tp);
1530 		}
1531 	}
1532 }
1533 
1534 
1535 int
1536 sscomrxintr(void *arg)
1537 {
1538 	struct sscom_softc *sc = arg;
1539 	bus_space_tag_t iot = sc->sc_iot;
1540 	bus_space_handle_t ioh = sc->sc_ioh;
1541 	u_char *put, *end;
1542 	u_int cc;
1543 
1544 	if (SSCOM_ISALIVE(sc) == 0)
1545 		return 0;
1546 
1547 	SSCOM_LOCK(sc);
1548 
1549 	end = sc->sc_ebuf;
1550 	put = sc->sc_rbput;
1551 	cc = sc->sc_rbavail;
1552 
1553 	do {
1554 		u_char	msts, delta;
1555 		u_char  uerstat;
1556 		uint16_t ufstat;
1557 
1558 		ufstat = bus_space_read_2(iot, ioh, SSCOM_UFSTAT);
1559 
1560 		/* XXX: break interrupt with no character? */
1561 
1562 		if ( (ufstat & (UFSTAT_RXCOUNT|UFSTAT_RXFULL)) &&
1563 		    !ISSET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED)) {
1564 
1565 			while (cc > 0) {
1566 				int cn_trapped = 0;
1567 
1568 				/* get status and received character.
1569 				   read status register first */
1570 				uerstat = sscom_geterr(iot, ioh);
1571 				put[0] = sscom_getc(iot, ioh);
1572 
1573 				if (ISSET(uerstat, UERSTAT_BREAK)) {
1574 					int con_trapped = 0;
1575 					cn_check_magic(sc->sc_tty->t_dev,
1576 					    CNC_BREAK, sscom_cnm_state);
1577 					if (con_trapped)
1578 						continue;
1579 #if defined(KGDB)
1580 					if (ISSET(sc->sc_hwflags,
1581 					    SSCOM_HW_KGDB)) {
1582 						kgdb_connect(1);
1583 						continue;
1584 					}
1585 #endif
1586 				}
1587 
1588 				put[1] = uerstat;
1589 				cn_check_magic(sc->sc_tty->t_dev,
1590 					       put[0], sscom_cnm_state);
1591 				if (!cn_trapped) {
1592 					put += 2;
1593 					if (put >= end)
1594 						put = sc->sc_rbuf;
1595 					cc--;
1596 				}
1597 
1598 				ufstat = bus_space_read_2(iot, ioh, SSCOM_UFSTAT);
1599 				if ( (ufstat & (UFSTAT_RXFULL|UFSTAT_RXCOUNT)) == 0 )
1600 					break;
1601 			}
1602 
1603 			/*
1604 			 * Current string of incoming characters ended because
1605 			 * no more data was available or we ran out of space.
1606 			 * Schedule a receive event if any data was received.
1607 			 * If we're out of space, turn off receive interrupts.
1608 			 */
1609 			sc->sc_rbput = put;
1610 			sc->sc_rbavail = cc;
1611 			if (!ISSET(sc->sc_rx_flags, RX_TTY_OVERFLOWED))
1612 				sc->sc_rx_ready = 1;
1613 
1614 			/*
1615 			 * See if we are in danger of overflowing a buffer. If
1616 			 * so, use hardware flow control to ease the pressure.
1617 			 */
1618 			if (!ISSET(sc->sc_rx_flags, RX_IBUF_BLOCKED) &&
1619 			    cc < sc->sc_r_hiwat) {
1620 				SET(sc->sc_rx_flags, RX_IBUF_BLOCKED);
1621 				sscom_hwiflow(sc);
1622 			}
1623 
1624 			/*
1625 			 * If we're out of space, disable receive interrupts
1626 			 * until the queue has drained a bit.
1627 			 */
1628 			if (!cc) {
1629 				SET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED);
1630 				sscom_disable_rxint(sc);
1631 				sc->sc_ucon &= ~UCON_ERRINT;
1632 				bus_space_write_2(iot, ioh, SSCOM_UCON, sc->sc_ucon);
1633 			}
1634 		}
1635 
1636 
1637 		msts = sc->read_modem_status(sc);
1638 		delta = msts ^ sc->sc_msts;
1639 		sc->sc_msts = msts;
1640 
1641 #ifdef notyet
1642 		/*
1643 		 * Pulse-per-second (PSS) signals on edge of DCD?
1644 		 * Process these even if line discipline is ignoring DCD.
1645 		 */
1646 		if (delta & sc->sc_ppsmask) {
1647 			struct timeval tv;
1648 		    	if ((msr & sc->sc_ppsmask) == sc->sc_ppsassert) {
1649 				/* XXX nanotime() */
1650 				microtime(&tv);
1651 				TIMEVAL_TO_TIMESPEC(&tv,
1652 				    &sc->ppsinfo.assert_timestamp);
1653 				if (sc->ppsparam.mode & PPS_OFFSETASSERT) {
1654 					timespecadd(&sc->ppsinfo.assert_timestamp,
1655 					    &sc->ppsparam.assert_offset,
1656 						    &sc->ppsinfo.assert_timestamp);
1657 				}
1658 
1659 #ifdef PPS_SYNC
1660 				if (sc->ppsparam.mode & PPS_HARDPPSONASSERT)
1661 					hardpps(&tv, tv.tv_usec);
1662 #endif
1663 				sc->ppsinfo.assert_sequence++;
1664 				sc->ppsinfo.current_mode = sc->ppsparam.mode;
1665 
1666 			} else if ((msr & sc->sc_ppsmask) == sc->sc_ppsclear) {
1667 				/* XXX nanotime() */
1668 				microtime(&tv);
1669 				TIMEVAL_TO_TIMESPEC(&tv,
1670 				    &sc->ppsinfo.clear_timestamp);
1671 				if (sc->ppsparam.mode & PPS_OFFSETCLEAR) {
1672 					timespecadd(&sc->ppsinfo.clear_timestamp,
1673 					    &sc->ppsparam.clear_offset,
1674 					    &sc->ppsinfo.clear_timestamp);
1675 				}
1676 
1677 #ifdef PPS_SYNC
1678 				if (sc->ppsparam.mode & PPS_HARDPPSONCLEAR)
1679 					hardpps(&tv, tv.tv_usec);
1680 #endif
1681 				sc->ppsinfo.clear_sequence++;
1682 				sc->ppsinfo.current_mode = sc->ppsparam.mode;
1683 			}
1684 		}
1685 #endif
1686 
1687 		/*
1688 		 * Process normal status changes
1689 		 */
1690 		if (ISSET(delta, sc->sc_msr_mask)) {
1691 			SET(sc->sc_msr_delta, delta);
1692 
1693 			/*
1694 			 * Stop output immediately if we lose the output
1695 			 * flow control signal or carrier detect.
1696 			 */
1697 			if (ISSET(~msts, sc->sc_msr_mask)) {
1698 				sc->sc_tbc = 0;
1699 				sc->sc_heldtbc = 0;
1700 #ifdef SSCOM_DEBUG
1701 				if (sscom_debug)
1702 					sscomstatus(sc, "sscomintr  ");
1703 #endif
1704 			}
1705 
1706 			sc->sc_st_check = 1;
1707 		}
1708 
1709 		/*
1710 		 * Done handling any receive interrupts.
1711 		 */
1712 
1713 		/*
1714 		 * If we've delayed a parameter change, do it
1715 		 * now, and restart * output.
1716 		 */
1717 		if ((ufstat & UFSTAT_TXCOUNT) == 0) {
1718 			/* XXX: we should check transmitter empty also */
1719 
1720 			if (sc->sc_heldchange) {
1721 				sscom_loadchannelregs(sc);
1722 				sc->sc_heldchange = 0;
1723 				sc->sc_tbc = sc->sc_heldtbc;
1724 				sc->sc_heldtbc = 0;
1725 			}
1726 		}
1727 
1728 
1729 	} while (0);
1730 
1731 	SSCOM_UNLOCK(sc);
1732 
1733 	/* Wake up the poller. */
1734 	softint_schedule(sc->sc_si);
1735 
1736 #ifdef RND_COM
1737 	rnd_add_uint32(&sc->rnd_source, iir | rsr);
1738 #endif
1739 
1740 	return 1;
1741 }
1742 
1743 int
1744 sscomtxintr(void *arg)
1745 {
1746 	struct sscom_softc *sc = arg;
1747 	bus_space_tag_t iot = sc->sc_iot;
1748 	bus_space_handle_t ioh = sc->sc_ioh;
1749 	uint16_t ufstat;
1750 
1751 	if (SSCOM_ISALIVE(sc) == 0)
1752 		return 0;
1753 
1754 	SSCOM_LOCK(sc);
1755 
1756 	ufstat = bus_space_read_2(iot, ioh, SSCOM_UFSTAT);
1757 
1758 	/*
1759 	 * If we've delayed a parameter change, do it
1760 	 * now, and restart * output.
1761 	 */
1762 	if (sc->sc_heldchange && (ufstat & UFSTAT_TXCOUNT) == 0) {
1763 		/* XXX: we should check transmitter empty also */
1764 		sscom_loadchannelregs(sc);
1765 		sc->sc_heldchange = 0;
1766 		sc->sc_tbc = sc->sc_heldtbc;
1767 		sc->sc_heldtbc = 0;
1768 	}
1769 
1770 	/*
1771 	 * See if data can be transmitted as well. Schedule tx
1772 	 * done event if no data left and tty was marked busy.
1773 	 */
1774 	if (!ISSET(ufstat,UFSTAT_TXFULL)) {
1775 		/*
1776 		 * Output the next chunk of the contiguous
1777 		 * buffer, if any.
1778 		 */
1779 		if (sc->sc_tbc > 0) {
1780 			__sscom_output_chunk(sc, ufstat);
1781 		}
1782 		else {
1783 			/*
1784 			 * Disable transmit sscompletion
1785 			 * interrupts if necessary.
1786 			 */
1787 			if (sc->sc_hwflags & SSCOM_HW_TXINT)
1788 				sscom_disable_txint(sc);
1789 			if (sc->sc_tx_busy) {
1790 				sc->sc_tx_busy = 0;
1791 				sc->sc_tx_done = 1;
1792 			}
1793 		}
1794 	}
1795 
1796 	SSCOM_UNLOCK(sc);
1797 
1798 	/* Wake up the poller. */
1799 	softint_schedule(sc->sc_si);
1800 
1801 #ifdef RND_COM
1802 	rnd_add_uint32(&sc->rnd_source, iir | rsr);
1803 #endif
1804 
1805 	return 1;
1806 }
1807 
1808 
1809 #if defined(KGDB) || defined(SSCOM0CONSOLE) || defined(SSCOM1CONSOLE)
1810 /*
1811  * Initialize UART for use as console or KGDB line.
1812  */
1813 static int
1814 sscom_init(bus_space_tag_t iot, const struct sscom_uart_info *config,
1815     int rate, int frequency, tcflag_t cflag, bus_space_handle_t *iohp)
1816 {
1817 	bus_space_handle_t ioh;
1818 	bus_addr_t iobase = config->iobase;
1819 
1820 	if (bus_space_map(iot, iobase, SSCOM_SIZE, 0, &ioh))
1821 		return ENOMEM; /* ??? */
1822 
1823 	bus_space_write_2(iot, ioh, SSCOM_UCON, 0);
1824 	bus_space_write_1(iot, ioh, SSCOM_UFCON,
1825 #ifdef SSCOM_S3C2440
1826 	    UFCON_TXTRIGGER_16 | UFCON_RXTRIGGER_16 |
1827 #else
1828 	    UFCON_TXTRIGGER_8 | UFCON_RXTRIGGER_8 |
1829 #endif
1830 	    UFCON_TXFIFO_RESET | UFCON_RXFIFO_RESET |
1831 	    UFCON_FIFO_ENABLE );
1832 	/* tx/rx fifo reset are auto-cleared */
1833 
1834 	rate = sscomspeed(rate, frequency);
1835 	bus_space_write_2(iot, ioh, SSCOM_UBRDIV, rate);
1836 	bus_space_write_2(iot, ioh, SSCOM_ULCON, cflag2lcr(cflag));
1837 
1838 	/* enable UART */
1839 	bus_space_write_2(iot, ioh, SSCOM_UCON,
1840 	    UCON_TXMODE_INT|UCON_RXMODE_INT);
1841 	bus_space_write_2(iot, ioh, SSCOM_UMCON, UMCON_RTS);
1842 
1843 	*iohp = ioh;
1844 	return 0;
1845 }
1846 
1847 #endif
1848 
1849 #if defined(SSCOM0CONSOLE) || defined(SSCOM1CONSOLE)
1850 /*
1851  * Following are all routines needed for SSCOM to act as console
1852  */
1853 struct consdev sscomcons = {
1854 	NULL, NULL, sscomcngetc, sscomcnputc, sscomcnpollc, NULL,
1855 	NULL, NULL, NODEV, CN_NORMAL
1856 };
1857 
1858 
1859 int
1860 sscom_cnattach(bus_space_tag_t iot, const struct sscom_uart_info *config,
1861     int rate, int frequency, tcflag_t cflag)
1862 {
1863 	int res;
1864 
1865 	res = sscom_init(iot, config, rate, frequency, cflag, &sscomconsioh);
1866 	if (res)
1867 		return res;
1868 
1869 	cn_tab = &sscomcons;
1870 	cn_init_magic(&sscom_cnm_state);
1871 	cn_set_magic("\047\001"); /* default magic is BREAK */
1872 
1873 	sscomconstag = iot;
1874 	sscomconsunit = config->unit;
1875 	sscomconsrate = rate;
1876 	sscomconscflag = cflag;
1877 
1878 	return 0;
1879 }
1880 
1881 void
1882 sscom_cndetach(void)
1883 {
1884 	bus_space_unmap(sscomconstag, sscomconsioh, SSCOM_SIZE);
1885 	sscomconstag = NULL;
1886 
1887 	cn_tab = NULL;
1888 }
1889 
1890 /*
1891  * The read-ahead code is so that you can detect pending in-band
1892  * cn_magic in polled mode while doing output rather than having to
1893  * wait until the kernel decides it needs input.
1894  */
1895 
1896 #define MAX_READAHEAD	20
1897 static int sscom_readahead[MAX_READAHEAD];
1898 static int sscom_readaheadcount = 0;
1899 
1900 int
1901 sscomcngetc(dev_t dev)
1902 {
1903 	int s = splserial();
1904 	u_char stat, c;
1905 
1906 	/* got a character from reading things earlier */
1907 	if (sscom_readaheadcount > 0) {
1908 		int i;
1909 
1910 		c = sscom_readahead[0];
1911 		for (i = 1; i < sscom_readaheadcount; i++) {
1912 			sscom_readahead[i-1] = sscom_readahead[i];
1913 		}
1914 		sscom_readaheadcount--;
1915 		splx(s);
1916 		return c;
1917 	}
1918 
1919 	/* block until a character becomes available */
1920 	while (!sscom_rxrdy(sscomconstag, sscomconsioh))
1921 		;
1922 
1923 	c = sscom_getc(sscomconstag, sscomconsioh);
1924 	stat = sscom_geterr(sscomconstag, sscomconsioh);
1925 	{
1926 		int cn_trapped = 0; /* unused */
1927 #ifdef DDB
1928 		extern int db_active;
1929 		if (!db_active)
1930 #endif
1931 			cn_check_magic(dev, c, sscom_cnm_state);
1932 	}
1933 	splx(s);
1934 	return c;
1935 }
1936 
1937 /*
1938  * Console kernel output character routine.
1939  */
1940 void
1941 sscomcnputc(dev_t dev, int c)
1942 {
1943 	int s = splserial();
1944 	int timo;
1945 
1946 	int cin, stat;
1947 	if (sscom_readaheadcount < MAX_READAHEAD &&
1948 	    sscom_rxrdy(sscomconstag, sscomconsioh)) {
1949 
1950 		int cn_trapped = 0;
1951 		cin = sscom_getc(sscomconstag, sscomconsioh);
1952 		stat = sscom_geterr(sscomconstag, sscomconsioh);
1953 		cn_check_magic(dev, cin, sscom_cnm_state);
1954 		sscom_readahead[sscom_readaheadcount++] = cin;
1955 	}
1956 
1957 	/* wait for any pending transmission to finish */
1958 	timo = 150000;
1959 	while (ISSET(bus_space_read_2(sscomconstag, sscomconsioh, SSCOM_UFSTAT),
1960 		   UFSTAT_TXFULL) && --timo)
1961 		continue;
1962 
1963 	bus_space_write_1(sscomconstag, sscomconsioh, SSCOM_UTXH, c);
1964 	SSCOM_BARRIER(sscomconstag, sscomconsioh, BR | BW);
1965 
1966 #if 0
1967 	/* wait for this transmission to complete */
1968 	timo = 1500000;
1969 	while (!ISSET(bus_space_read_1(sscomconstag, sscomconsioh, SSCOM_UTRSTAT),
1970 		   UTRSTAT_TXEMPTY) && --timo)
1971 		continue;
1972 #endif
1973 	splx(s);
1974 }
1975 
1976 void
1977 sscomcnpollc(dev_t dev, int on)
1978 {
1979 
1980 	sscom_readaheadcount = 0;
1981 }
1982 
1983 #endif /* SSCOM0CONSOLE||SSCOM1CONSOLE */
1984 
1985 #ifdef KGDB
1986 int
1987 sscom_kgdb_attach(bus_space_tag_t iot, const struct sscom_uart_info *config,
1988     int rate, int frequency, tcflag_t cflag)
1989 {
1990 	int res;
1991 
1992 	if (iot == sscomconstag && config->unit == sscomconsunit) {
1993 		printf( "console==kgdb_port (%d): kgdb disabled\n", sscomconsunit);
1994 		return EBUSY; /* cannot share with console */
1995 	}
1996 
1997 	res = sscom_init(iot, config, rate, frequency, cflag, &sscom_kgdb_ioh);
1998 	if (res)
1999 		return res;
2000 
2001 	kgdb_attach(sscom_kgdb_getc, sscom_kgdb_putc, NULL);
2002 	kgdb_dev = 123; /* unneeded, only to satisfy some tests */
2003 
2004 	sscom_kgdb_iot = iot;
2005 	sscom_kgdb_unit = config->unit;
2006 
2007 	return 0;
2008 }
2009 
2010 /* ARGSUSED */
2011 int
2012 sscom_kgdb_getc(void *arg)
2013 {
2014 	int c, stat;
2015 
2016 	/* block until a character becomes available */
2017 	while (!sscom_rxrdy(sscom_kgdb_iot, sscom_kgdb_ioh))
2018 		;
2019 
2020 	c = sscom_getc(sscom_kgdb_iot, sscom_kgdb_ioh);
2021 	stat = sscom_geterr(sscom_kgdb_iot, sscom_kgdb_ioh);
2022 
2023 	return c;
2024 }
2025 
2026 /* ARGSUSED */
2027 void
2028 sscom_kgdb_putc(void *arg, int c)
2029 {
2030 	int timo;
2031 
2032 	/* wait for any pending transmission to finish */
2033 	timo = 150000;
2034 	while (ISSET(bus_space_read_2(sscom_kgdb_iot, sscom_kgdb_ioh,
2035 	    SSCOM_UFSTAT), UFSTAT_TXFULL) && --timo)
2036 		continue;
2037 
2038 	bus_space_write_1(sscom_kgdb_iot, sscom_kgdb_ioh, SSCOM_UTXH, c);
2039 	SSCOM_BARRIER(sscom_kgdb_iot, sscom_kgdb_ioh, BR | BW);
2040 
2041 #if 0
2042 	/* wait for this transmission to complete */
2043 	timo = 1500000;
2044 	while (!ISSET(bus_space_read_1(sscom_kgdb_iot, sscom_kgdb_ioh,
2045 	    SSCOM_UTRSTAT), UTRSTAT_TXEMPTY) && --timo)
2046 		continue;
2047 #endif
2048 }
2049 #endif /* KGDB */
2050 
2051 /* helper function to identify the sscom ports used by
2052  console or KGDB (and not yet autoconf attached) */
2053 int
2054 sscom_is_console(bus_space_tag_t iot, int unit,
2055     bus_space_handle_t *ioh)
2056 {
2057 	bus_space_handle_t help;
2058 
2059 	if (!sscomconsattached &&
2060 	    iot == sscomconstag && unit == sscomconsunit)
2061 		help = sscomconsioh;
2062 #ifdef KGDB
2063 	else if (!sscom_kgdb_attached &&
2064 	    iot == sscom_kgdb_iot && unit == sscom_kgdb_unit)
2065 		help = sscom_kgdb_ioh;
2066 #endif
2067 	else
2068 		return 0;
2069 
2070 	if (ioh)
2071 		*ioh = help;
2072 	return 1;
2073 }
2074