xref: /netbsd-src/sys/arch/arm/ep93xx/epcom.c (revision 8b0f9554ff8762542c4defc4f70e1eb76fb508fa)
1 /*	$NetBSD: epcom.c,v 1.15 2007/11/19 18:51:38 ad Exp $ */
2 /*
3  * Copyright (c) 1998, 1999, 2001, 2002, 2004 The NetBSD Foundation, Inc.
4  * All rights reserved.
5  *
6  * This code is derived from software contributed to The NetBSD Foundation
7  * by Jesse Off
8  *
9  * This code is derived from software contributed to The NetBSD Foundation
10  * by Ichiro FUKUHARA and Naoto Shimazaki.
11  *
12  * This code is derived from software contributed to The NetBSD Foundation
13  * by IWAMOTO Toshihiro.
14  *
15  * This code is derived from software contributed to The NetBSD Foundation
16  * by Charles M. Hannum.
17  *
18  * Redistribution and use in source and binary forms, with or without
19  * modification, are permitted provided that the following conditions
20  * are met:
21  * 1. Redistributions of source code must retain the above copyright
22  *    notice, this list of conditions and the following disclaimer.
23  * 2. Redistributions in binary form must reproduce the above copyright
24  *    notice, this list of conditions and the following disclaimer in the
25  *    documentation and/or other materials provided with the distribution.
26  * 3. All advertising materials mentioning features or use of this software
27  *    must display the following acknowledgement:
28  *        This product includes software developed by the NetBSD
29  *        Foundation, Inc. and its contributors.
30  * 4. Neither the name of The NetBSD Foundation nor the names of its
31  *    contributors may be used to endorse or promote products derived
32  *    from this software without specific prior written permission.
33  *
34  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
35  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
36  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
37  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
38  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
39  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
40  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
41  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
42  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
43  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
44  * POSSIBILITY OF SUCH DAMAGE.
45  */
46 
47 /*
48  * Copyright (c) 1991 The Regents of the University of California.
49  * All rights reserved.
50  *
51  * Redistribution and use in source and binary forms, with or without
52  * modification, are permitted provided that the following conditions
53  * are met:
54  * 1. Redistributions of source code must retain the above copyright
55  *    notice, this list of conditions and the following disclaimer.
56  * 2. Redistributions in binary form must reproduce the above copyright
57  *    notice, this list of conditions and the following disclaimer in the
58  *    documentation and/or other materials provided with the distribution.
59  * 3. Neither the name of the University nor the names of its contributors
60  *    may be used to endorse or promote products derived from this software
61  *    without specific prior written permission.
62  *
63  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
64  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
65  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
66  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
67  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
68  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
69  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
70  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
71  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
72  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
73  * SUCH DAMAGE.
74  *
75  *      @(#)com.c       7.5 (Berkeley) 5/16/91
76  */
77 
78 /*
79  * TODO: hardware flow control
80  */
81 
82 #include <sys/cdefs.h>
83 __KERNEL_RCSID(0, "$NetBSD: epcom.c,v 1.15 2007/11/19 18:51:38 ad Exp $");
84 
85 #include "opt_ddb.h"
86 #include "opt_kgdb.h"
87 #include "epcom.h"
88 
89 #include "rnd.h"
90 #if NRND > 0 && defined(RND_COM)
91 #include <sys/rnd.h>
92 #endif
93 
94 /*
95  * Override cnmagic(9) macro before including <sys/systm.h>.
96  * We need to know if cn_check_magic triggered debugger, so set a flag.
97  * Callers of cn_check_magic must declare int cn_trapped = 0;
98  * XXX: this is *ugly*!
99  */
100 #define cn_trap()				\
101 	do {					\
102 		console_debugger();		\
103 		cn_trapped = 1;			\
104 	} while (/* CONSTCOND */ 0)
105 
106 
107 #include <sys/param.h>
108 #include <sys/systm.h>
109 #include <sys/types.h>
110 #include <sys/conf.h>
111 #include <sys/file.h>
112 #include <sys/device.h>
113 #include <sys/kernel.h>
114 #include <sys/malloc.h>
115 #include <sys/tty.h>
116 #include <sys/uio.h>
117 #include <sys/vnode.h>
118 #include <sys/kauth.h>
119 
120 #include <machine/intr.h>
121 #include <machine/bus.h>
122 
123 #include <arm/ep93xx/epcomreg.h>
124 #include <arm/ep93xx/epcomvar.h>
125 #include <arm/ep93xx/ep93xxreg.h>
126 #include <arm/ep93xx/ep93xxvar.h>
127 
128 #include <dev/cons.h>
129 
130 static int	epcomparam(struct tty *, struct termios *);
131 static void	epcomstart(struct tty *);
132 static int	epcomhwiflow(struct tty *, int);
133 
134 static u_int	cflag2lcrhi(tcflag_t);
135 static void	epcom_iflush(struct epcom_softc *);
136 static void	epcom_set(struct epcom_softc *);
137 
138 int             epcomcngetc(dev_t);
139 void            epcomcnputc(dev_t, int);
140 void            epcomcnpollc(dev_t, int);
141 
142 static void	epcomsoft(void* arg);
143 inline static void	epcom_txsoft(struct epcom_softc *, struct tty *);
144 inline static void	epcom_rxsoft(struct epcom_softc *, struct tty *);
145 
146 void            epcomcnprobe(struct consdev *);
147 void            epcomcninit(struct consdev *);
148 
149 static struct epcom_cons_softc {
150 	bus_space_tag_t		sc_iot;
151 	bus_space_handle_t	sc_ioh;
152 	bus_addr_t		sc_hwbase;
153 	int			sc_ospeed;
154 	tcflag_t		sc_cflag;
155 	int			sc_attached;
156 } epcomcn_sc;
157 
158 static struct cnm_state epcom_cnm_state;
159 
160 extern struct cfdriver epcom_cd;
161 
162 dev_type_open(epcomopen);
163 dev_type_close(epcomclose);
164 dev_type_read(epcomread);
165 dev_type_write(epcomwrite);
166 dev_type_ioctl(epcomioctl);
167 dev_type_stop(epcomstop);
168 dev_type_tty(epcomtty);
169 dev_type_poll(epcompoll);
170 
171 const struct cdevsw epcom_cdevsw = {
172 	epcomopen, epcomclose, epcomread, epcomwrite, epcomioctl,
173 	epcomstop, epcomtty, epcompoll, nommap, ttykqfilter, D_TTY
174 };
175 
176 struct consdev epcomcons = {
177 	NULL, NULL, epcomcngetc, epcomcnputc, epcomcnpollc, NULL,
178 	NULL, NULL, NODEV, CN_NORMAL
179 };
180 
181 #ifndef DEFAULT_COMSPEED
182 #define DEFAULT_COMSPEED 115200
183 #endif
184 
185 #define COMUNIT_MASK    0x7ffff
186 #define COMDIALOUT_MASK 0x80000
187 
188 #define COMUNIT(x)	(minor(x) & COMUNIT_MASK)
189 #define COMDIALOUT(x)	(minor(x) & COMDIALOUT_MASK)
190 
191 #define COM_ISALIVE(sc)	((sc)->enabled != 0 && \
192 			device_is_active(&(sc)->sc_dev))
193 
194 void
195 epcom_attach_subr(struct epcom_softc *sc)
196 {
197 	struct tty *tp;
198 
199 	if (sc->sc_iot == epcomcn_sc.sc_iot
200 	    && sc->sc_hwbase == epcomcn_sc.sc_hwbase) {
201 		epcomcn_sc.sc_attached = 1;
202 		sc->sc_lcrlo = EPCOMSPEED2BRD(epcomcn_sc.sc_ospeed) & 0xff;
203 		sc->sc_lcrmid = EPCOMSPEED2BRD(epcomcn_sc.sc_ospeed) >> 8;
204 
205 		/* Make sure the console is always "hardwired". */
206 		delay(10000);	/* wait for output to finish */
207 		SET(sc->sc_hwflags, COM_HW_CONSOLE);
208 		SET(sc->sc_swflags, TIOCFLAG_SOFTCAR);
209 	}
210 
211 	tp = ttymalloc();
212 	tp->t_oproc = epcomstart;
213 	tp->t_param = epcomparam;
214 	tp->t_hwiflow = epcomhwiflow;
215 
216 	sc->sc_tty = tp;
217 	sc->sc_rbuf = malloc(EPCOM_RING_SIZE << 1, M_DEVBUF, M_NOWAIT);
218 	sc->sc_rbput = sc->sc_rbget = sc->sc_rbuf;
219 	sc->sc_rbavail = EPCOM_RING_SIZE;
220 	if (sc->sc_rbuf == NULL) {
221 		printf("%s: unable to allocate ring buffer\n",
222 		    sc->sc_dev.dv_xname);
223 		return;
224 	}
225 	sc->sc_ebuf = sc->sc_rbuf + (EPCOM_RING_SIZE << 1);
226 	sc->sc_tbc = 0;
227 
228 	sc->sc_lcrlo = EPCOMSPEED2BRD(DEFAULT_COMSPEED) & 0xff;
229 	sc->sc_lcrmid = EPCOMSPEED2BRD(DEFAULT_COMSPEED) >> 8;
230 	sc->sc_lcrhi = cflag2lcrhi(CS8); /* 8N1 */
231 
232 	tty_attach(tp);
233 
234 	if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
235 		int maj;
236 
237 		/* locate the major number */
238 		maj = cdevsw_lookup_major(&epcom_cdevsw);
239 
240 		cn_tab->cn_dev = makedev(maj, device_unit(&sc->sc_dev));
241 
242 		aprint_normal("%s: console\n", sc->sc_dev.dv_xname);
243 	}
244 
245 	sc->sc_si = softintr_establish(IPL_SOFTSERIAL, epcomsoft, sc);
246 
247 #if NRND > 0 && defined(RND_COM)
248 	rnd_attach_source(&sc->rnd_source, sc->sc_dev.dv_xname,
249 			  RND_TYPE_TTY, 0);
250 #endif
251 
252 	/* if there are no enable/disable functions, assume the device
253 	   is always enabled */
254 	if (!sc->enable)
255 		sc->enabled = 1;
256 
257 	/* XXX configure register */
258 	/* xxx_config(sc) */
259 
260 	SET(sc->sc_hwflags, COM_HW_DEV_OK);
261 }
262 
263 static int
264 epcomparam(struct tty *tp, struct termios *t)
265 {
266 	struct epcom_softc *sc
267 		= device_lookup(&epcom_cd, COMUNIT(tp->t_dev));
268 	int s;
269 
270 	if (COM_ISALIVE(sc) == 0)
271 		return (EIO);
272 
273 	if (t->c_ispeed && t->c_ispeed != t->c_ospeed)
274 		return (EINVAL);
275 
276 	/*
277 	 * For the console, always force CLOCAL and !HUPCL, so that the port
278 	 * is always active.
279 	 */
280 	if (ISSET(sc->sc_swflags, TIOCFLAG_SOFTCAR) ||
281 	    ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
282 		SET(t->c_cflag, CLOCAL);
283 		CLR(t->c_cflag, HUPCL);
284 	}
285 
286 	/*
287 	 * If there were no changes, don't do anything.  This avoids dropping
288 	 * input and improves performance when all we did was frob things like
289 	 * VMIN and VTIME.
290 	 */
291 	if (tp->t_ospeed == t->c_ospeed &&
292 	    tp->t_cflag == t->c_cflag)
293 		return (0);
294 
295 	s = splserial();
296 
297 	sc->sc_lcrhi = cflag2lcrhi(t->c_cflag);
298 	sc->sc_lcrlo = EPCOMSPEED2BRD(t->c_ospeed) & 0xff;
299 	sc->sc_lcrmid = EPCOMSPEED2BRD(t->c_ospeed) >> 8;
300 
301 	/* And copy to tty. */
302 	tp->t_ispeed = 0;
303 	tp->t_ospeed = t->c_ospeed;
304 	tp->t_cflag = t->c_cflag;
305 	epcom_set(sc);
306 
307 	splx(s);
308 
309 	/*
310 	 * Update the tty layer's idea of the carrier bit.
311 	 * We tell tty the carrier is always on.
312 	 */
313 	(void) (*tp->t_linesw->l_modem)(tp, 1);
314 
315 #ifdef COM_DEBUG
316 	if (com_debug)
317 		comstatus(sc, "comparam ");
318 #endif
319 
320 	if (!ISSET(t->c_cflag, CHWFLOW)) {
321 		if (sc->sc_tx_stopped) {
322 			sc->sc_tx_stopped = 0;
323 			epcomstart(tp);
324 		}
325 	}
326 
327 	return (0);
328 }
329 
330 static int
331 epcomhwiflow(struct tty *tp, int block)
332 {
333 	return (0);
334 }
335 
336 static void
337 epcom_filltx(struct epcom_softc *sc)
338 {
339 	bus_space_tag_t iot = sc->sc_iot;
340 	bus_space_handle_t ioh = sc->sc_ioh;
341 	int n;
342 
343 	n = 0;
344         while ((bus_space_read_4(iot, ioh, EPCOM_Flag) & Flag_TXFF) == 0) {
345 		if (n >= sc->sc_tbc)
346 			break;
347 		bus_space_write_4(iot, ioh, EPCOM_Data,
348 				  0xff & *(sc->sc_tba + n));
349 		n++;
350         }
351         sc->sc_tbc -= n;
352         sc->sc_tba += n;
353 }
354 
355 static void
356 epcomstart(struct tty *tp)
357 {
358 	struct epcom_softc *sc
359 		= device_lookup(&epcom_cd, COMUNIT(tp->t_dev));
360 	int s;
361 
362 	if (COM_ISALIVE(sc) == 0)
363 		return;
364 
365 	s = spltty();
366 	if (ISSET(tp->t_state, TS_BUSY | TS_TIMEOUT | TS_TTSTOP))
367 		goto out;
368 	if (sc->sc_tx_stopped)
369 		goto out;
370 	if (!ttypull(tp))
371 		goto out;
372 
373 	/* Grab the first contiguous region of buffer space. */
374 	{
375 		u_char *tba;
376 		int tbc;
377 
378 		tba = tp->t_outq.c_cf;
379 		tbc = ndqb(&tp->t_outq, 0);
380 
381 		(void)splserial();
382 
383 		sc->sc_tba = tba;
384 		sc->sc_tbc = tbc;
385 	}
386 
387 	SET(tp->t_state, TS_BUSY);
388 	sc->sc_tx_busy = 1;
389 
390 	/* Output the first chunk of the contiguous buffer. */
391 	epcom_filltx(sc);
392 
393 	if (!ISSET(sc->sc_ctrl, Ctrl_TIE)) {
394 		SET(sc->sc_ctrl, Ctrl_TIE);
395 		epcom_set(sc);
396 	}
397 
398 out:
399 	splx(s);
400 	return;
401 }
402 
403 static void
404 epcom_break(struct epcom_softc *sc, int onoff)
405 {
406 	if (onoff)
407 		SET(sc->sc_lcrhi, LinCtrlHigh_BRK);
408 	else
409 		CLR(sc->sc_lcrhi, LinCtrlHigh_BRK);
410 	epcom_set(sc);
411 }
412 
413 static void
414 epcom_shutdown(struct epcom_softc *sc)
415 {
416 	int s;
417 
418 	s = splserial();
419 
420 	/* Turn off interrupts. */
421 	CLR(sc->sc_ctrl, (Ctrl_TIE|Ctrl_RTIE|Ctrl_RIE));
422 
423 	/* Clear any break condition set with TIOCSBRK. */
424 	epcom_break(sc, 0);
425 	epcom_set(sc);
426 
427 	if (sc->disable) {
428 #ifdef DIAGNOSTIC
429 		if (!sc->enabled)
430 			panic("epcom_shutdown: not enabled?");
431 #endif
432 		(*sc->disable)(sc);
433 		sc->enabled = 0;
434 	}
435 	splx(s);
436 }
437 
438 int
439 epcomopen(dev_t dev, int flag, int mode, struct lwp *l)
440 {
441 	struct epcom_softc *sc;
442 	struct tty *tp;
443 	int s, s2;
444 	int error;
445 
446 	sc = device_lookup(&epcom_cd, COMUNIT(dev));
447 	if (sc == NULL || !ISSET(sc->sc_hwflags, COM_HW_DEV_OK) ||
448 		sc->sc_rbuf == NULL)
449 		return (ENXIO);
450 
451 	if (!device_is_active(&sc->sc_dev))
452 		return (ENXIO);
453 
454 #ifdef KGDB
455 	/*
456 	 * If this is the kgdb port, no other use is permitted.
457 	 */
458 	if (ISSET(sc->sc_hwflags, COM_HW_KGDB))
459 		return (EBUSY);
460 #endif
461 
462 	tp = sc->sc_tty;
463 
464 	if (kauth_authorize_device_tty(l->l_cred, KAUTH_DEVICE_TTY_OPEN, tp))
465 		return (EBUSY);
466 
467 	s = spltty();
468 
469 	/*
470 	 * Do the following iff this is a first open.
471 	 */
472 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
473 		struct termios t;
474 
475 		tp->t_dev = dev;
476 
477 		s2 = splserial();
478 
479 		if (sc->enable) {
480 			if ((*sc->enable)(sc)) {
481 				splx(s2);
482 				splx(s);
483 				printf("%s: device enable failed\n",
484 				       sc->sc_dev.dv_xname);
485 				return (EIO);
486 			}
487 			sc->enabled = 1;
488 #if 0
489 /* XXXXXXXXXXXXXXX */
490 			com_config(sc);
491 #endif
492 		}
493 
494 		/* Turn on interrupts. */
495 		SET(sc->sc_ctrl, (Ctrl_UARTE|Ctrl_RIE|Ctrl_RTIE));
496 		epcom_set(sc);
497 
498 #if 0
499 		/* Fetch the current modem control status, needed later. */
500 		sc->sc_msr = bus_space_read_1(sc->sc_iot, sc->sc_ioh, com_msr);
501 
502 		/* Clear PPS capture state on first open. */
503 		sc->sc_ppsmask = 0;
504 		sc->ppsparam.mode = 0;
505 #endif
506 
507 		splx(s2);
508 
509 		/*
510 		 * Initialize the termios status to the defaults.  Add in the
511 		 * sticky bits from TIOCSFLAGS.
512 		 */
513 		t.c_ispeed = 0;
514 		if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
515 			t.c_ospeed = epcomcn_sc.sc_ospeed;
516 			t.c_cflag = epcomcn_sc.sc_cflag;
517 		} else {
518 			t.c_ospeed = TTYDEF_SPEED;
519 			t.c_cflag = TTYDEF_CFLAG;
520 		}
521 		if (ISSET(sc->sc_swflags, TIOCFLAG_CLOCAL))
522 			SET(t.c_cflag, CLOCAL);
523 		if (ISSET(sc->sc_swflags, TIOCFLAG_CRTSCTS))
524 			SET(t.c_cflag, CRTSCTS);
525 		if (ISSET(sc->sc_swflags, TIOCFLAG_MDMBUF))
526 			SET(t.c_cflag, MDMBUF);
527 		/* Make sure epcomparam() will do something. */
528 		tp->t_ospeed = 0;
529 		(void) epcomparam(tp, &t);
530 		tp->t_iflag = TTYDEF_IFLAG;
531 		tp->t_oflag = TTYDEF_OFLAG;
532 		tp->t_lflag = TTYDEF_LFLAG;
533 		ttychars(tp);
534 		ttsetwater(tp);
535 
536 		s2 = splserial();
537 
538 		/* Clear the input ring, and unblock. */
539 		sc->sc_rbput = sc->sc_rbget = sc->sc_rbuf;
540 		sc->sc_rbavail = EPCOM_RING_SIZE;
541 		epcom_iflush(sc);
542 		CLR(sc->sc_rx_flags, RX_ANY_BLOCK);
543 
544 #ifdef COM_DEBUG
545 		if (epcom_debug)
546 			comstatus(sc, "epcomopen  ");
547 #endif
548 
549 		splx(s2);
550 	}
551 
552 	splx(s);
553 
554 	error = ttyopen(tp, COMDIALOUT(dev), ISSET(flag, O_NONBLOCK));
555 	if (error)
556 		goto bad;
557 
558 	error = (*tp->t_linesw->l_open)(dev, tp);
559 	if (error)
560 		goto bad;
561 
562 	return (0);
563 
564 bad:
565 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
566 		/*
567 		 * We failed to open the device, and nobody else had it opened.
568 		 * Clean up the state as appropriate.
569 		 */
570 		epcom_shutdown(sc);
571 	}
572 
573 	return (error);
574 }
575 
576 int
577 epcomclose(dev_t dev, int flag, int mode, struct lwp *l)
578 {
579 	struct epcom_softc *sc = device_lookup(&epcom_cd, COMUNIT(dev));
580 	struct tty *tp = sc->sc_tty;
581 
582 	/* XXX This is for cons.c. */
583 	if (!ISSET(tp->t_state, TS_ISOPEN))
584 		return (0);
585 
586 	(*tp->t_linesw->l_close)(tp, flag);
587 	ttyclose(tp);
588 
589 	if (COM_ISALIVE(sc) == 0)
590 		return (0);
591 
592 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
593 		/*
594 		 * Although we got a last close, the device may still be in
595 		 * use; e.g. if this was the dialout node, and there are still
596 		 * processes waiting for carrier on the non-dialout node.
597 		 */
598 		epcom_shutdown(sc);
599 	}
600 
601 	return (0);
602 }
603 
604 int
605 epcomread(dev_t dev, struct uio *uio, int flag)
606 {
607 	struct epcom_softc *sc = device_lookup(&epcom_cd, COMUNIT(dev));
608 	struct tty *tp = sc->sc_tty;
609 
610 	if (COM_ISALIVE(sc) == 0)
611 		return (EIO);
612 
613 	return ((*tp->t_linesw->l_read)(tp, uio, flag));
614 }
615 
616 int
617 epcomwrite(dev_t dev, struct uio *uio, int flag)
618 {
619 	struct epcom_softc *sc = device_lookup(&epcom_cd, COMUNIT(dev));
620 	struct tty *tp = sc->sc_tty;
621 
622 	if (COM_ISALIVE(sc) == 0)
623 		return (EIO);
624 
625 	return ((*tp->t_linesw->l_write)(tp, uio, flag));
626 }
627 
628 int
629 epcompoll(dev_t dev, int events, struct lwp *l)
630 {
631 	struct epcom_softc *sc = device_lookup(&epcom_cd, COMUNIT(dev));
632 	struct tty *tp = sc->sc_tty;
633 
634 	if (COM_ISALIVE(sc) == 0)
635 		return (EIO);
636 
637 	return ((*tp->t_linesw->l_poll)(tp, events, l));
638 }
639 
640 struct tty *
641 epcomtty(dev_t dev)
642 {
643 	struct epcom_softc *sc = device_lookup(&epcom_cd, COMUNIT(dev));
644 	struct tty *tp = sc->sc_tty;
645 
646 	return (tp);
647 }
648 
649 int
650 epcomioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l)
651 {
652 	struct epcom_softc *sc = device_lookup(&epcom_cd, COMUNIT(dev));
653 	struct tty *tp = sc->sc_tty;
654 	int error;
655 	int s;
656 
657 	if (COM_ISALIVE(sc) == 0)
658 		return (EIO);
659 
660 	error = (*tp->t_linesw->l_ioctl)(tp, cmd, data, flag, l);
661 	if (error != EPASSTHROUGH)
662 		return (error);
663 
664 	error = ttioctl(tp, cmd, data, flag, l);
665 	if (error != EPASSTHROUGH)
666 		return (error);
667 
668 	error = 0;
669 
670 	s = splserial();
671 
672 	switch (cmd) {
673 	case TIOCSBRK:
674 		epcom_break(sc, 1);
675 		break;
676 
677 	case TIOCCBRK:
678 		epcom_break(sc, 0);
679 		break;
680 
681 	case TIOCGFLAGS:
682 		*(int *)data = sc->sc_swflags;
683 		break;
684 
685 	case TIOCSFLAGS:
686 		error = kauth_authorize_device_tty(l->l_cred,
687 		    KAUTH_DEVICE_TTY_PRIVSET, tp);
688 		if (error)
689 			break;
690 		sc->sc_swflags = *(int *)data;
691 		break;
692 
693 	default:
694 		error = EPASSTHROUGH;
695 		break;
696 	}
697 
698 	splx(s);
699 
700 	return (error);
701 }
702 
703 /*
704  * Stop output on a line.
705  */
706 void
707 epcomstop(struct tty *tp, int flag)
708 {
709 	struct epcom_softc *sc
710 		= device_lookup(&epcom_cd, COMUNIT(tp->t_dev));
711 	int s;
712 
713 	s = splserial();
714 	if (ISSET(tp->t_state, TS_BUSY)) {
715 		/* Stop transmitting at the next chunk. */
716 		sc->sc_tbc = 0;
717 		if (!ISSET(tp->t_state, TS_TTSTOP))
718 			SET(tp->t_state, TS_FLUSH);
719 	}
720 	splx(s);
721 }
722 
723 static u_int
724 cflag2lcrhi(tcflag_t cflag)
725 {
726 	u_int lcrhi;
727 
728 	switch (cflag & CSIZE) {
729 	case CS7:
730 		lcrhi = 0x40;
731 		break;
732 	case CS6:
733 		lcrhi = 0x20;
734 		break;
735 	case CS8:
736 	default:
737 		lcrhi = 0x60;
738 		break;
739 	}
740 	lcrhi |= (cflag & PARENB) ? LinCtrlHigh_PEN : 0;
741 	lcrhi |= (cflag & PARODD) ? 0 : LinCtrlHigh_EPS;
742 	lcrhi |= (cflag & CSTOPB) ? LinCtrlHigh_STP2 : 0;
743 	lcrhi |= LinCtrlHigh_FEN;  /* FIFO always enabled */
744 
745 	return (lcrhi);
746 }
747 
748 static void
749 epcom_iflush(struct epcom_softc *sc)
750 {
751 	bus_space_tag_t iot = sc->sc_iot;
752 	bus_space_handle_t ioh = sc->sc_ioh;
753 #ifdef DIAGNOSTIC
754 	int reg;
755 #endif
756 	int timo;
757 
758 #ifdef DIAGNOSTIC
759 	reg = 0xffff;
760 #endif
761 	timo = 50000;
762 	/* flush any pending I/O */
763 	while ((bus_space_read_4(iot, ioh, EPCOM_Flag) & Flag_RXFE) == 0
764 	       && --timo)
765 #ifdef DIAGNOSTIC
766 		reg =
767 #else
768 			(void)
769 #endif
770 			bus_space_read_4(iot, ioh, EPCOM_Data);
771 #ifdef DIAGNOSTIC
772 	if (!timo)
773 		printf("%s: com_iflush timeout %02x\n", sc->sc_dev.dv_xname,
774 		       reg);
775 #endif
776 }
777 
778 static void
779 epcom_set(struct epcom_softc *sc)
780 {
781 	bus_space_write_4(sc->sc_iot, sc->sc_ioh, EPCOM_LinCtrlLow,
782 			  sc->sc_lcrlo);
783 	bus_space_write_4(sc->sc_iot, sc->sc_ioh, EPCOM_LinCtrlMid,
784 			  sc->sc_lcrmid);
785 	bus_space_write_4(sc->sc_iot, sc->sc_ioh, EPCOM_LinCtrlHigh,
786 			  sc->sc_lcrhi);
787 	bus_space_write_4(sc->sc_iot, sc->sc_ioh, EPCOM_Ctrl,
788 			  sc->sc_ctrl);
789 }
790 
791 int
792 epcomcnattach(bus_space_tag_t iot, bus_addr_t iobase, bus_space_handle_t ioh,
793     int ospeed, tcflag_t cflag)
794 {
795 	u_int lcrlo, lcrmid, lcrhi, ctrl, pwrcnt;
796 	bus_space_handle_t syscon_ioh;
797 
798 	cn_tab = &epcomcons;
799 	cn_init_magic(&epcom_cnm_state);
800 	cn_set_magic("\047\001");
801 
802 	epcomcn_sc.sc_iot = iot;
803 	epcomcn_sc.sc_ioh = ioh;
804 	epcomcn_sc.sc_hwbase = iobase;
805 	epcomcn_sc.sc_ospeed = ospeed;
806 	epcomcn_sc.sc_cflag = cflag;
807 
808 	lcrhi = cflag2lcrhi(cflag);
809 	lcrlo = EPCOMSPEED2BRD(ospeed) & 0xff;
810 	lcrmid = EPCOMSPEED2BRD(ospeed) >> 8;
811 	ctrl = Ctrl_UARTE;
812 
813 	bus_space_map(iot, EP93XX_APB_HWBASE + EP93XX_APB_SYSCON,
814 		EP93XX_APB_SYSCON_SIZE, 0, &syscon_ioh);
815 	pwrcnt = bus_space_read_4(iot, syscon_ioh, EP93XX_SYSCON_PwrCnt);
816 	pwrcnt &= ~(PwrCnt_UARTBAUD);
817 	bus_space_write_4(iot, syscon_ioh, EP93XX_SYSCON_PwrCnt, pwrcnt);
818 	bus_space_unmap(iot, syscon_ioh, EP93XX_APB_SYSCON_SIZE);
819 
820 	bus_space_write_4(iot, ioh, EPCOM_LinCtrlLow, lcrlo);
821 	bus_space_write_4(iot, ioh, EPCOM_LinCtrlMid, lcrmid);
822 	bus_space_write_4(iot, ioh, EPCOM_LinCtrlHigh, lcrhi);
823 	bus_space_write_4(iot, ioh, EPCOM_Ctrl, ctrl);
824 
825 	return (0);
826 }
827 
828 void
829 epcomcnprobe(struct consdev *cp)
830 {
831 	cp->cn_pri = CN_REMOTE;
832 }
833 
834 void
835 epcomcnpollc(dev_t dev, int on)
836 {
837 }
838 
839 void
840 epcomcnputc(dev_t dev, int c)
841 {
842 	int			s;
843 	bus_space_tag_t		iot = epcomcn_sc.sc_iot;
844 	bus_space_handle_t	ioh = epcomcn_sc.sc_ioh;
845 
846 	s = splserial();
847 
848 	while((bus_space_read_4(iot, ioh, EPCOM_Flag) & Flag_TXFF) != 0)
849 		;
850 
851 	bus_space_write_4(iot, ioh, EPCOM_Data, c);
852 
853 #ifdef DEBUG
854 	if (c == '\r') {
855 		while((bus_space_read_4(iot, ioh, EPCOM_Flag) & Flag_TXFE) == 0)
856 			;
857 	}
858 #endif
859 
860 	splx(s);
861 }
862 
863 int
864 epcomcngetc(dev_t dev)
865 {
866 	int			c, sts;
867 	int			s;
868 	bus_space_tag_t		iot = epcomcn_sc.sc_iot;
869 	bus_space_handle_t	ioh = epcomcn_sc.sc_ioh;
870 
871         s = splserial();
872 
873 	while((bus_space_read_4(iot, ioh, EPCOM_Flag) & Flag_RXFE) != 0)
874 		;
875 
876 	c = bus_space_read_4(iot, ioh, EPCOM_Data);
877 	sts = bus_space_read_4(iot, ioh, EPCOM_RXSts);
878 	if (ISSET(sts, RXSts_BE)) c = CNC_BREAK;
879 #ifdef DDB
880 	extern int db_active;
881 	if (!db_active)
882 #endif
883 	{
884 		int cn_trapped = 0; /* unused */
885 
886 		cn_check_magic(dev, c, epcom_cnm_state);
887 	}
888 	c &= 0xff;
889 	splx(s);
890 
891 	return (c);
892 }
893 
894 inline static void
895 epcom_txsoft(struct epcom_softc *sc, struct tty *tp)
896 {
897 	CLR(tp->t_state, TS_BUSY);
898 	if (ISSET(tp->t_state, TS_FLUSH))
899 		CLR(tp->t_state, TS_FLUSH);
900         else
901 		ndflush(&tp->t_outq, (int)(sc->sc_tba - tp->t_outq.c_cf));
902 	(*tp->t_linesw->l_start)(tp);
903 }
904 
905 inline static void
906 epcom_rxsoft(struct epcom_softc *sc, struct tty *tp)
907 {
908 	int (*rint) __P((int, struct tty *)) = tp->t_linesw->l_rint;
909 	u_char *get, *end;
910 	u_int cc, scc;
911 	u_char sts;
912 	int code;
913 	int s;
914 
915 	end = sc->sc_ebuf;
916 	get = sc->sc_rbget;
917 	scc = cc = EPCOM_RING_SIZE - sc->sc_rbavail;
918 #if 0
919 	if (cc == EPCOM_RING_SIZE) {
920 		sc->sc_floods++;
921 		if (sc->sc_errors++ == 0)
922 			callout_reset(&sc->sc_diag_callout, 60 * hz,
923 			    comdiag, sc);
924 	}
925 #endif
926 	while (cc) {
927 		code = get[0];
928 		sts = get[1];
929 		if (ISSET(sts, RXSts_OE | RXSts_FE | RXSts_PE | RXSts_BE)) {
930 #if 0
931 			if (ISSET(lsr, DR_ROR)) {
932 				sc->sc_overflows++;
933 				if (sc->sc_errors++ == 0)
934 					callout_reset(&sc->sc_diag_callout,
935 					    60 * hz, comdiag, sc);
936 			}
937 #endif
938 			if (ISSET(sts, (RXSts_FE|RXSts_BE)))
939 				SET(code, TTY_FE);
940 			if (ISSET(sts, RXSts_PE))
941 				SET(code, TTY_PE);
942 		}
943 		if ((*rint)(code, tp) == -1) {
944 			/*
945 			 * The line discipline's buffer is out of space.
946 			 */
947 			if (!ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED)) {
948 				/*
949 				 * We're either not using flow control, or the
950 				 * line discipline didn't tell us to block for
951 				 * some reason.  Either way, we have no way to
952 				 * know when there's more space available, so
953 				 * just drop the rest of the data.
954 				 */
955 				get += cc << 1;
956 				if (get >= end)
957 					get -= EPCOM_RING_SIZE << 1;
958 				cc = 0;
959 			} else {
960 				/*
961 				 * Don't schedule any more receive processing
962 				 * until the line discipline tells us there's
963 				 * space available (through comhwiflow()).
964 				 * Leave the rest of the data in the input
965 				 * buffer.
966 				 */
967 				SET(sc->sc_rx_flags, RX_TTY_OVERFLOWED);
968 			}
969 			break;
970 		}
971 		get += 2;
972 		if (get >= end)
973 			get = sc->sc_rbuf;
974 		cc--;
975 	}
976 
977 	if (cc != scc) {
978 		sc->sc_rbget = get;
979 		s = splserial();
980 
981 		cc = sc->sc_rbavail += scc - cc;
982 		/* Buffers should be ok again, release possible block. */
983 		if (cc >= 1) {
984 			if (ISSET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED)) {
985 				CLR(sc->sc_rx_flags, RX_IBUF_OVERFLOWED);
986 				SET(sc->sc_ctrl, (Ctrl_RIE|Ctrl_RTIE));
987 				epcom_set(sc);
988 			}
989 			if (ISSET(sc->sc_rx_flags, RX_IBUF_BLOCKED)) {
990 				CLR(sc->sc_rx_flags, RX_IBUF_BLOCKED);
991 #if 0
992 				com_hwiflow(sc);
993 #endif
994 			}
995 		}
996 		splx(s);
997 	}
998 }
999 
1000 static void
1001 epcomsoft(void* arg)
1002 {
1003 	struct epcom_softc *sc = arg;
1004 
1005 	if (COM_ISALIVE(sc) == 0)
1006 		return;
1007 
1008 	if (sc->sc_rx_ready) {
1009 		sc->sc_rx_ready = 0;
1010 		epcom_rxsoft(sc, sc->sc_tty);
1011 	}
1012 	if (sc->sc_tx_done) {
1013 		sc->sc_tx_done = 0;
1014 		epcom_txsoft(sc, sc->sc_tty);
1015 	}
1016 }
1017 
1018 int
1019 epcomintr(void* arg)
1020 {
1021 	struct epcom_softc *sc = arg;
1022 	bus_space_tag_t iot = sc->sc_iot;
1023 	bus_space_handle_t ioh = sc->sc_ioh;
1024 	u_char *put, *end;
1025 	u_int cc;
1026 	u_int flagr;
1027 	u_int intr;
1028 	u_int32_t c, csts;
1029 
1030 	intr = bus_space_read_4(iot, ioh, EPCOM_IntIDIntClr);
1031 
1032 	if (COM_ISALIVE(sc) == 0)
1033 		panic("intr on disabled epcom");
1034 
1035 	flagr = bus_space_read_4(iot, ioh, EPCOM_Flag);
1036 
1037 	end = sc->sc_ebuf;
1038 	put = sc->sc_rbput;
1039 	cc = sc->sc_rbavail;
1040 
1041 	if (!(ISSET(flagr, Flag_RXFE))) {
1042 		if (!ISSET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED)) {
1043 			while (cc > 0) {
1044 				if (ISSET(flagr, Flag_RXFE))
1045 					break;
1046 				c = bus_space_read_4(iot, ioh, EPCOM_Data);
1047 				csts = bus_space_read_4(iot, ioh, EPCOM_RXSts);
1048 				if (ISSET(csts, RXSts_BE)) {
1049 					int cn_trapped = 0;
1050 
1051 					cn_check_magic(sc->sc_tty->t_dev,
1052 					  CNC_BREAK, epcom_cnm_state);
1053 					if (cn_trapped)
1054 						goto next;
1055 #if defined(KGDB) && !defined(DDB)
1056 					if (ISSET(sc->sc_hwflags, COM_HW_KGDB)){
1057 						kgdb_connect(1);
1058 						goto next;
1059 					}
1060 #endif
1061 				} else {
1062 					int cn_trapped = 0;
1063 
1064 					cn_check_magic(sc->sc_tty->t_dev,
1065 					  (c & 0xff), epcom_cnm_state);
1066 					if (cn_trapped)
1067 						goto next;
1068 				}
1069 
1070 
1071 				put[0] = c & 0xff;
1072 				put[1] = csts & 0xf;
1073 				put += 2;
1074 				if (put >= end)
1075 					put = sc->sc_rbuf;
1076 				cc--;
1077 			next:
1078 				flagr = bus_space_read_4(iot, ioh, EPCOM_Flag);
1079 			}
1080 
1081 			/*
1082 			 * Current string of incoming characters ended because
1083 			 * no more data was available or we ran out of space.
1084 			 * Schedule a receive event if any data was received.
1085 			 * If we're out of space, turn off receive interrupts.
1086 			 */
1087 			sc->sc_rbput = put;
1088 			sc->sc_rbavail = cc;
1089 			if (!ISSET(sc->sc_rx_flags, RX_TTY_OVERFLOWED))
1090 				sc->sc_rx_ready = 1;
1091 
1092 			/*
1093 			 * See if we are in danger of overflowing a buffer. If
1094 			 * so, use hardware flow control to ease the pressure.
1095 			 */
1096 
1097 			/* but epcom cannot. X-( */
1098 
1099 			/*
1100 			 * If we're out of space, disable receive interrupts
1101 			 * until the queue has drained a bit.
1102 			 */
1103 			if (!cc) {
1104 				SET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED);
1105 				CLR(sc->sc_ctrl, (Ctrl_RIE|Ctrl_RTIE));
1106 				epcom_set(sc);
1107 			}
1108 		} else {
1109 #ifdef DIAGNOSTIC
1110 			panic("epcomintr: we shouldn't reach here");
1111 #endif
1112 			CLR(sc->sc_ctrl, (Ctrl_RIE|Ctrl_RTIE));
1113 			epcom_set(sc);
1114 		}
1115 	}
1116 
1117 	/*
1118 	 * Done handling any receive interrupts. See if data can be
1119 	 * transmitted as well. Schedule tx done event if no data left
1120 	 * and tty was marked busy.
1121 	 */
1122 
1123 	if (!ISSET(flagr, Flag_TXFF) && sc->sc_tbc > 0) {
1124 		/* Output the next chunk of the contiguous buffer, if any. */
1125 		epcom_filltx(sc);
1126 	} else {
1127 		/* Disable transmit completion interrupts if necessary. */
1128 		if (ISSET(sc->sc_ctrl, Ctrl_TIE)) {
1129 			CLR(sc->sc_ctrl, Ctrl_TIE);
1130 			epcom_set(sc);
1131 		}
1132 		if (sc->sc_tx_busy) {
1133 			sc->sc_tx_busy = 0;
1134 			sc->sc_tx_done = 1;
1135 		}
1136 	}
1137 
1138 	/* Wake up the poller. */
1139 	softintr_schedule(sc->sc_si);
1140 
1141 #if 0 /* XXX: broken */
1142 #if NRND > 0 && defined(RND_COM)
1143 	rnd_add_uint32(&sc->rnd_source, intr ^ flagr);
1144 #endif
1145 #endif
1146 	return (1);
1147 }
1148