xref: /netbsd-src/sys/arch/arm/ep93xx/epcom.c (revision fad4c9f71477ae11cea2ee75ec82151ac770a534)
1 /*	$NetBSD: epcom.c,v 1.10 2006/05/14 21:55:09 elad 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 1.10 2006/05/14 21:55:09 elad 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 
371 	if (tp->t_outq.c_cc <= tp->t_lowat) {
372 		if (ISSET(tp->t_state, TS_ASLEEP)) {
373 			CLR(tp->t_state, TS_ASLEEP);
374 			wakeup(&tp->t_outq);
375 		}
376 		selwakeup(&tp->t_wsel);
377 		if (tp->t_outq.c_cc == 0)
378 			goto out;
379 	}
380 
381 	/* Grab the first contiguous region of buffer space. */
382 	{
383 		u_char *tba;
384 		int tbc;
385 
386 		tba = tp->t_outq.c_cf;
387 		tbc = ndqb(&tp->t_outq, 0);
388 
389 		(void)splserial();
390 
391 		sc->sc_tba = tba;
392 		sc->sc_tbc = tbc;
393 	}
394 
395 	SET(tp->t_state, TS_BUSY);
396 	sc->sc_tx_busy = 1;
397 
398 	/* Output the first chunk of the contiguous buffer. */
399 	epcom_filltx(sc);
400 
401 	if (!ISSET(sc->sc_ctrl, Ctrl_TIE)) {
402 		SET(sc->sc_ctrl, Ctrl_TIE);
403 		epcom_set(sc);
404 	}
405 
406 out:
407 	splx(s);
408 	return;
409 }
410 
411 static void
412 epcom_break(struct epcom_softc *sc, int onoff)
413 {
414 	if (onoff)
415 		SET(sc->sc_lcrhi, LinCtrlHigh_BRK);
416 	else
417 		CLR(sc->sc_lcrhi, LinCtrlHigh_BRK);
418 	epcom_set(sc);
419 }
420 
421 static void
422 epcom_shutdown(struct epcom_softc *sc)
423 {
424 	int s;
425 
426 	s = splserial();
427 
428 	/* Turn off interrupts. */
429 	CLR(sc->sc_ctrl, (Ctrl_TIE|Ctrl_RTIE|Ctrl_RIE));
430 
431 	/* Clear any break condition set with TIOCSBRK. */
432 	epcom_break(sc, 0);
433 	epcom_set(sc);
434 
435 	if (sc->disable) {
436 #ifdef DIAGNOSTIC
437 		if (!sc->enabled)
438 			panic("epcom_shutdown: not enabled?");
439 #endif
440 		(*sc->disable)(sc);
441 		sc->enabled = 0;
442 	}
443 	splx(s);
444 }
445 
446 int
447 epcomopen(dev_t dev, int flag, int mode, struct lwp *l)
448 {
449 	struct epcom_softc *sc;
450 	struct tty *tp;
451 	int s, s2;
452 	int error;
453 
454 	sc = device_lookup(&epcom_cd, COMUNIT(dev));
455 	if (sc == NULL || !ISSET(sc->sc_hwflags, COM_HW_DEV_OK) ||
456 		sc->sc_rbuf == NULL)
457 		return (ENXIO);
458 
459 	if (!device_is_active(&sc->sc_dev))
460 		return (ENXIO);
461 
462 #ifdef KGDB
463 	/*
464 	 * If this is the kgdb port, no other use is permitted.
465 	 */
466 	if (ISSET(sc->sc_hwflags, COM_HW_KGDB))
467 		return (EBUSY);
468 #endif
469 
470 	tp = sc->sc_tty;
471 
472 	if (ISSET(tp->t_state, TS_ISOPEN) &&
473 	    ISSET(tp->t_state, TS_XCLUDE) &&
474 	    kauth_authorize_generic(l->l_proc->p_cred, KAUTH_GENERIC_ISSUSER, &l->l_proc->p_acflag) != 0)
475 		return (EBUSY);
476 
477 	s = spltty();
478 
479 	/*
480 	 * Do the following iff this is a first open.
481 	 */
482 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
483 		struct termios t;
484 
485 		tp->t_dev = dev;
486 
487 		s2 = splserial();
488 
489 		if (sc->enable) {
490 			if ((*sc->enable)(sc)) {
491 				splx(s2);
492 				splx(s);
493 				printf("%s: device enable failed\n",
494 				       sc->sc_dev.dv_xname);
495 				return (EIO);
496 			}
497 			sc->enabled = 1;
498 #if 0
499 /* XXXXXXXXXXXXXXX */
500 			com_config(sc);
501 #endif
502 		}
503 
504 		/* Turn on interrupts. */
505 		SET(sc->sc_ctrl, (Ctrl_UARTE|Ctrl_RIE|Ctrl_RTIE));
506 		epcom_set(sc);
507 
508 #if 0
509 		/* Fetch the current modem control status, needed later. */
510 		sc->sc_msr = bus_space_read_1(sc->sc_iot, sc->sc_ioh, com_msr);
511 
512 		/* Clear PPS capture state on first open. */
513 		sc->sc_ppsmask = 0;
514 		sc->ppsparam.mode = 0;
515 #endif
516 
517 		splx(s2);
518 
519 		/*
520 		 * Initialize the termios status to the defaults.  Add in the
521 		 * sticky bits from TIOCSFLAGS.
522 		 */
523 		t.c_ispeed = 0;
524 		if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
525 			t.c_ospeed = epcomcn_sc.sc_ospeed;
526 			t.c_cflag = epcomcn_sc.sc_cflag;
527 		} else {
528 			t.c_ospeed = TTYDEF_SPEED;
529 			t.c_cflag = TTYDEF_CFLAG;
530 		}
531 		if (ISSET(sc->sc_swflags, TIOCFLAG_CLOCAL))
532 			SET(t.c_cflag, CLOCAL);
533 		if (ISSET(sc->sc_swflags, TIOCFLAG_CRTSCTS))
534 			SET(t.c_cflag, CRTSCTS);
535 		if (ISSET(sc->sc_swflags, TIOCFLAG_MDMBUF))
536 			SET(t.c_cflag, MDMBUF);
537 		/* Make sure epcomparam() will do something. */
538 		tp->t_ospeed = 0;
539 		(void) epcomparam(tp, &t);
540 		tp->t_iflag = TTYDEF_IFLAG;
541 		tp->t_oflag = TTYDEF_OFLAG;
542 		tp->t_lflag = TTYDEF_LFLAG;
543 		ttychars(tp);
544 		ttsetwater(tp);
545 
546 		s2 = splserial();
547 
548 		/* Clear the input ring, and unblock. */
549 		sc->sc_rbput = sc->sc_rbget = sc->sc_rbuf;
550 		sc->sc_rbavail = EPCOM_RING_SIZE;
551 		epcom_iflush(sc);
552 		CLR(sc->sc_rx_flags, RX_ANY_BLOCK);
553 
554 #ifdef COM_DEBUG
555 		if (epcom_debug)
556 			comstatus(sc, "epcomopen  ");
557 #endif
558 
559 		splx(s2);
560 	}
561 
562 	splx(s);
563 
564 	error = ttyopen(tp, COMDIALOUT(dev), ISSET(flag, O_NONBLOCK));
565 	if (error)
566 		goto bad;
567 
568 	error = (*tp->t_linesw->l_open)(dev, tp);
569 	if (error)
570 		goto bad;
571 
572 	return (0);
573 
574 bad:
575 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
576 		/*
577 		 * We failed to open the device, and nobody else had it opened.
578 		 * Clean up the state as appropriate.
579 		 */
580 		epcom_shutdown(sc);
581 	}
582 
583 	return (error);
584 }
585 
586 int
587 epcomclose(dev_t dev, int flag, int mode, struct lwp *l)
588 {
589 	struct epcom_softc *sc = device_lookup(&epcom_cd, COMUNIT(dev));
590 	struct tty *tp = sc->sc_tty;
591 
592 	/* XXX This is for cons.c. */
593 	if (!ISSET(tp->t_state, TS_ISOPEN))
594 		return (0);
595 
596 	(*tp->t_linesw->l_close)(tp, flag);
597 	ttyclose(tp);
598 
599 	if (COM_ISALIVE(sc) == 0)
600 		return (0);
601 
602 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
603 		/*
604 		 * Although we got a last close, the device may still be in
605 		 * use; e.g. if this was the dialout node, and there are still
606 		 * processes waiting for carrier on the non-dialout node.
607 		 */
608 		epcom_shutdown(sc);
609 	}
610 
611 	return (0);
612 }
613 
614 int
615 epcomread(dev_t dev, struct uio *uio, int flag)
616 {
617 	struct epcom_softc *sc = device_lookup(&epcom_cd, COMUNIT(dev));
618 	struct tty *tp = sc->sc_tty;
619 
620 	if (COM_ISALIVE(sc) == 0)
621 		return (EIO);
622 
623 	return ((*tp->t_linesw->l_read)(tp, uio, flag));
624 }
625 
626 int
627 epcomwrite(dev_t dev, struct uio *uio, int flag)
628 {
629 	struct epcom_softc *sc = device_lookup(&epcom_cd, COMUNIT(dev));
630 	struct tty *tp = sc->sc_tty;
631 
632 	if (COM_ISALIVE(sc) == 0)
633 		return (EIO);
634 
635 	return ((*tp->t_linesw->l_write)(tp, uio, flag));
636 }
637 
638 int
639 epcompoll(dev_t dev, int events, struct lwp *l)
640 {
641 	struct epcom_softc *sc = device_lookup(&epcom_cd, COMUNIT(dev));
642 	struct tty *tp = sc->sc_tty;
643 
644 	if (COM_ISALIVE(sc) == 0)
645 		return (EIO);
646 
647 	return ((*tp->t_linesw->l_poll)(tp, events, l));
648 }
649 
650 struct tty *
651 epcomtty(dev_t dev)
652 {
653 	struct epcom_softc *sc = device_lookup(&epcom_cd, COMUNIT(dev));
654 	struct tty *tp = sc->sc_tty;
655 
656 	return (tp);
657 }
658 
659 int
660 epcomioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct lwp *l)
661 {
662 	struct epcom_softc *sc = device_lookup(&epcom_cd, COMUNIT(dev));
663 	struct tty *tp = sc->sc_tty;
664 	int error;
665 	int s;
666 
667 	if (COM_ISALIVE(sc) == 0)
668 		return (EIO);
669 
670 	error = (*tp->t_linesw->l_ioctl)(tp, cmd, data, flag, l);
671 	if (error != EPASSTHROUGH)
672 		return (error);
673 
674 	error = ttioctl(tp, cmd, data, flag, l);
675 	if (error != EPASSTHROUGH)
676 		return (error);
677 
678 	error = 0;
679 
680 	s = splserial();
681 
682 	switch (cmd) {
683 	case TIOCSBRK:
684 		epcom_break(sc, 1);
685 		break;
686 
687 	case TIOCCBRK:
688 		epcom_break(sc, 0);
689 		break;
690 
691 	case TIOCGFLAGS:
692 		*(int *)data = sc->sc_swflags;
693 		break;
694 
695 	case TIOCSFLAGS:
696 		error = kauth_authorize_generic(l->l_proc->p_cred, KAUTH_GENERIC_ISSUSER, &l->l_proc->p_acflag);
697 		if (error)
698 			break;
699 		sc->sc_swflags = *(int *)data;
700 		break;
701 
702 	default:
703 		error = EPASSTHROUGH;
704 		break;
705 	}
706 
707 	splx(s);
708 
709 	return (error);
710 }
711 
712 /*
713  * Stop output on a line.
714  */
715 void
716 epcomstop(struct tty *tp, int flag)
717 {
718 	struct epcom_softc *sc
719 		= device_lookup(&epcom_cd, COMUNIT(tp->t_dev));
720 	int s;
721 
722 	s = splserial();
723 	if (ISSET(tp->t_state, TS_BUSY)) {
724 		/* Stop transmitting at the next chunk. */
725 		sc->sc_tbc = 0;
726 		if (!ISSET(tp->t_state, TS_TTSTOP))
727 			SET(tp->t_state, TS_FLUSH);
728 	}
729 	splx(s);
730 }
731 
732 static u_int
733 cflag2lcrhi(tcflag_t cflag)
734 {
735 	u_int lcrhi;
736 
737 	switch (cflag & CSIZE) {
738 	case CS7:
739 		lcrhi = 0x40;
740 		break;
741 	case CS6:
742 		lcrhi = 0x20;
743 		break;
744 	case CS8:
745 	default:
746 		lcrhi = 0x60;
747 		break;
748 	}
749 	lcrhi |= (cflag & PARENB) ? LinCtrlHigh_PEN : 0;
750 	lcrhi |= (cflag & PARODD) ? 0 : LinCtrlHigh_EPS;
751 	lcrhi |= (cflag & CSTOPB) ? LinCtrlHigh_STP2 : 0;
752 	lcrhi |= LinCtrlHigh_FEN;  /* FIFO always enabled */
753 
754 	return (lcrhi);
755 }
756 
757 static void
758 epcom_iflush(struct epcom_softc *sc)
759 {
760 	bus_space_tag_t iot = sc->sc_iot;
761 	bus_space_handle_t ioh = sc->sc_ioh;
762 #ifdef DIAGNOSTIC
763 	int reg;
764 #endif
765 	int timo;
766 
767 #ifdef DIAGNOSTIC
768 	reg = 0xffff;
769 #endif
770 	timo = 50000;
771 	/* flush any pending I/O */
772 	while ((bus_space_read_4(iot, ioh, EPCOM_Flag) & Flag_RXFE) == 0
773 	       && --timo)
774 #ifdef DIAGNOSTIC
775 		reg =
776 #else
777 			(void)
778 #endif
779 			bus_space_read_4(iot, ioh, EPCOM_Data);
780 #ifdef DIAGNOSTIC
781 	if (!timo)
782 		printf("%s: com_iflush timeout %02x\n", sc->sc_dev.dv_xname,
783 		       reg);
784 #endif
785 }
786 
787 static void
788 epcom_set(struct epcom_softc *sc)
789 {
790 	bus_space_write_4(sc->sc_iot, sc->sc_ioh, EPCOM_LinCtrlLow,
791 			  sc->sc_lcrlo);
792 	bus_space_write_4(sc->sc_iot, sc->sc_ioh, EPCOM_LinCtrlMid,
793 			  sc->sc_lcrmid);
794 	bus_space_write_4(sc->sc_iot, sc->sc_ioh, EPCOM_LinCtrlHigh,
795 			  sc->sc_lcrhi);
796 	bus_space_write_4(sc->sc_iot, sc->sc_ioh, EPCOM_Ctrl,
797 			  sc->sc_ctrl);
798 }
799 
800 int
801 epcomcnattach(bus_space_tag_t iot, bus_addr_t iobase, bus_space_handle_t ioh,
802     int ospeed, tcflag_t cflag)
803 {
804 	u_int lcrlo, lcrmid, lcrhi, ctrl, pwrcnt;
805 	bus_space_handle_t syscon_ioh;
806 
807 	cn_tab = &epcomcons;
808 	cn_init_magic(&epcom_cnm_state);
809 	cn_set_magic("\047\001");
810 
811 	epcomcn_sc.sc_iot = iot;
812 	epcomcn_sc.sc_ioh = ioh;
813 	epcomcn_sc.sc_hwbase = iobase;
814 	epcomcn_sc.sc_ospeed = ospeed;
815 	epcomcn_sc.sc_cflag = cflag;
816 
817 	lcrhi = cflag2lcrhi(cflag);
818 	lcrlo = EPCOMSPEED2BRD(ospeed) & 0xff;
819 	lcrmid = EPCOMSPEED2BRD(ospeed) >> 8;
820 	ctrl = Ctrl_UARTE;
821 
822 	bus_space_map(iot, EP93XX_APB_HWBASE + EP93XX_APB_SYSCON,
823 		EP93XX_APB_SYSCON_SIZE, 0, &syscon_ioh);
824 	pwrcnt = bus_space_read_4(iot, syscon_ioh, EP93XX_SYSCON_PwrCnt);
825 	pwrcnt &= ~(PwrCnt_UARTBAUD);
826 	bus_space_write_4(iot, syscon_ioh, EP93XX_SYSCON_PwrCnt, pwrcnt);
827 	bus_space_unmap(iot, syscon_ioh, EP93XX_APB_SYSCON_SIZE);
828 
829 	bus_space_write_4(iot, ioh, EPCOM_LinCtrlLow, lcrlo);
830 	bus_space_write_4(iot, ioh, EPCOM_LinCtrlMid, lcrmid);
831 	bus_space_write_4(iot, ioh, EPCOM_LinCtrlHigh, lcrhi);
832 	bus_space_write_4(iot, ioh, EPCOM_Ctrl, ctrl);
833 
834 	return (0);
835 }
836 
837 void
838 epcomcnprobe(struct consdev *cp)
839 {
840 	cp->cn_pri = CN_REMOTE;
841 }
842 
843 void
844 epcomcnpollc(dev_t dev, int on)
845 {
846 }
847 
848 void
849 epcomcnputc(dev_t dev, int c)
850 {
851 	int			s;
852 	bus_space_tag_t		iot = epcomcn_sc.sc_iot;
853 	bus_space_handle_t	ioh = epcomcn_sc.sc_ioh;
854 
855 	s = splserial();
856 
857 	while((bus_space_read_4(iot, ioh, EPCOM_Flag) & Flag_TXFF) != 0)
858 		;
859 
860 	bus_space_write_4(iot, ioh, EPCOM_Data, c);
861 
862 #ifdef DEBUG
863 	if (c == '\r') {
864 		while((bus_space_read_4(iot, ioh, EPCOM_Flag) & Flag_TXFE) == 0)
865 			;
866 	}
867 #endif
868 
869 	splx(s);
870 }
871 
872 int
873 epcomcngetc(dev_t dev)
874 {
875 	int			c, sts;
876 	int			s;
877 	bus_space_tag_t		iot = epcomcn_sc.sc_iot;
878 	bus_space_handle_t	ioh = epcomcn_sc.sc_ioh;
879 
880         s = splserial();
881 
882 	while((bus_space_read_4(iot, ioh, EPCOM_Flag) & Flag_RXFE) != 0)
883 		;
884 
885 	c = bus_space_read_4(iot, ioh, EPCOM_Data);
886 	sts = bus_space_read_4(iot, ioh, EPCOM_RXSts);
887 	if (ISSET(sts, RXSts_BE)) c = CNC_BREAK;
888 #ifdef DDB
889 	extern int db_active;
890 	if (!db_active)
891 #endif
892 	{
893 		int cn_trapped = 0; /* unused */
894 
895 		cn_check_magic(dev, c, epcom_cnm_state);
896 	}
897 	c &= 0xff;
898 	splx(s);
899 
900 	return (c);
901 }
902 
903 inline static void
904 epcom_txsoft(struct epcom_softc *sc, struct tty *tp)
905 {
906 	CLR(tp->t_state, TS_BUSY);
907 	if (ISSET(tp->t_state, TS_FLUSH))
908 		CLR(tp->t_state, TS_FLUSH);
909         else
910 		ndflush(&tp->t_outq, (int)(sc->sc_tba - tp->t_outq.c_cf));
911 	(*tp->t_linesw->l_start)(tp);
912 }
913 
914 inline static void
915 epcom_rxsoft(struct epcom_softc *sc, struct tty *tp)
916 {
917 	int (*rint) __P((int, struct tty *)) = tp->t_linesw->l_rint;
918 	u_char *get, *end;
919 	u_int cc, scc;
920 	u_char sts;
921 	int code;
922 	int s;
923 
924 	end = sc->sc_ebuf;
925 	get = sc->sc_rbget;
926 	scc = cc = EPCOM_RING_SIZE - sc->sc_rbavail;
927 #if 0
928 	if (cc == EPCOM_RING_SIZE) {
929 		sc->sc_floods++;
930 		if (sc->sc_errors++ == 0)
931 			callout_reset(&sc->sc_diag_callout, 60 * hz,
932 			    comdiag, sc);
933 	}
934 #endif
935 	while (cc) {
936 		code = get[0];
937 		sts = get[1];
938 		if (ISSET(sts, RXSts_OE | RXSts_FE | RXSts_PE | RXSts_BE)) {
939 #if 0
940 			if (ISSET(lsr, DR_ROR)) {
941 				sc->sc_overflows++;
942 				if (sc->sc_errors++ == 0)
943 					callout_reset(&sc->sc_diag_callout,
944 					    60 * hz, comdiag, sc);
945 			}
946 #endif
947 			if (ISSET(sts, (RXSts_FE|RXSts_BE)))
948 				SET(code, TTY_FE);
949 			if (ISSET(sts, RXSts_PE))
950 				SET(code, TTY_PE);
951 		}
952 		if ((*rint)(code, tp) == -1) {
953 			/*
954 			 * The line discipline's buffer is out of space.
955 			 */
956 			if (!ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED)) {
957 				/*
958 				 * We're either not using flow control, or the
959 				 * line discipline didn't tell us to block for
960 				 * some reason.  Either way, we have no way to
961 				 * know when there's more space available, so
962 				 * just drop the rest of the data.
963 				 */
964 				get += cc << 1;
965 				if (get >= end)
966 					get -= EPCOM_RING_SIZE << 1;
967 				cc = 0;
968 			} else {
969 				/*
970 				 * Don't schedule any more receive processing
971 				 * until the line discipline tells us there's
972 				 * space available (through comhwiflow()).
973 				 * Leave the rest of the data in the input
974 				 * buffer.
975 				 */
976 				SET(sc->sc_rx_flags, RX_TTY_OVERFLOWED);
977 			}
978 			break;
979 		}
980 		get += 2;
981 		if (get >= end)
982 			get = sc->sc_rbuf;
983 		cc--;
984 	}
985 
986 	if (cc != scc) {
987 		sc->sc_rbget = get;
988 		s = splserial();
989 
990 		cc = sc->sc_rbavail += scc - cc;
991 		/* Buffers should be ok again, release possible block. */
992 		if (cc >= 1) {
993 			if (ISSET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED)) {
994 				CLR(sc->sc_rx_flags, RX_IBUF_OVERFLOWED);
995 				SET(sc->sc_ctrl, (Ctrl_RIE|Ctrl_RTIE));
996 				epcom_set(sc);
997 			}
998 			if (ISSET(sc->sc_rx_flags, RX_IBUF_BLOCKED)) {
999 				CLR(sc->sc_rx_flags, RX_IBUF_BLOCKED);
1000 #if 0
1001 				com_hwiflow(sc);
1002 #endif
1003 			}
1004 		}
1005 		splx(s);
1006 	}
1007 }
1008 
1009 static void
1010 epcomsoft(void* arg)
1011 {
1012 	struct epcom_softc *sc = arg;
1013 
1014 	if (COM_ISALIVE(sc) == 0)
1015 		return;
1016 
1017 	if (sc->sc_rx_ready) {
1018 		sc->sc_rx_ready = 0;
1019 		epcom_rxsoft(sc, sc->sc_tty);
1020 	}
1021 	if (sc->sc_tx_done) {
1022 		sc->sc_tx_done = 0;
1023 		epcom_txsoft(sc, sc->sc_tty);
1024 	}
1025 }
1026 
1027 int
1028 epcomintr(void* arg)
1029 {
1030 	struct epcom_softc *sc = arg;
1031 	bus_space_tag_t iot = sc->sc_iot;
1032 	bus_space_handle_t ioh = sc->sc_ioh;
1033 	u_char *put, *end;
1034 	u_int cc;
1035 	u_int flagr;
1036 	u_int intr;
1037 	u_int32_t c, csts;
1038 
1039 	intr = bus_space_read_4(iot, ioh, EPCOM_IntIDIntClr);
1040 
1041 	if (COM_ISALIVE(sc) == 0)
1042 		panic("intr on disabled epcom");
1043 
1044 	flagr = bus_space_read_4(iot, ioh, EPCOM_Flag);
1045 
1046 	end = sc->sc_ebuf;
1047 	put = sc->sc_rbput;
1048 	cc = sc->sc_rbavail;
1049 
1050 	if (!(ISSET(flagr, Flag_RXFE))) {
1051 		if (!ISSET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED)) {
1052 			while (cc > 0) {
1053 				if (ISSET(flagr, Flag_RXFE))
1054 					break;
1055 				c = bus_space_read_4(iot, ioh, EPCOM_Data);
1056 				csts = bus_space_read_4(iot, ioh, EPCOM_RXSts);
1057 				if (ISSET(csts, RXSts_BE)) {
1058 					int cn_trapped = 0;
1059 
1060 					cn_check_magic(sc->sc_tty->t_dev,
1061 					  CNC_BREAK, epcom_cnm_state);
1062 					if (cn_trapped)
1063 						goto next;
1064 #if defined(KGDB) && !defined(DDB)
1065 					if (ISSET(sc->sc_hwflags, COM_HW_KGDB)){
1066 						kgdb_connect(1);
1067 						goto next;
1068 					}
1069 #endif
1070 				} else {
1071 					int cn_trapped = 0;
1072 
1073 					cn_check_magic(sc->sc_tty->t_dev,
1074 					  (c & 0xff), epcom_cnm_state);
1075 					if (cn_trapped)
1076 						goto next;
1077 				}
1078 
1079 
1080 				put[0] = c & 0xff;
1081 				put[1] = csts & 0xf;
1082 				put += 2;
1083 				if (put >= end)
1084 					put = sc->sc_rbuf;
1085 				cc--;
1086 			next:
1087 				flagr = bus_space_read_4(iot, ioh, EPCOM_Flag);
1088 			}
1089 
1090 			/*
1091 			 * Current string of incoming characters ended because
1092 			 * no more data was available or we ran out of space.
1093 			 * Schedule a receive event if any data was received.
1094 			 * If we're out of space, turn off receive interrupts.
1095 			 */
1096 			sc->sc_rbput = put;
1097 			sc->sc_rbavail = cc;
1098 			if (!ISSET(sc->sc_rx_flags, RX_TTY_OVERFLOWED))
1099 				sc->sc_rx_ready = 1;
1100 
1101 			/*
1102 			 * See if we are in danger of overflowing a buffer. If
1103 			 * so, use hardware flow control to ease the pressure.
1104 			 */
1105 
1106 			/* but epcom cannot. X-( */
1107 
1108 			/*
1109 			 * If we're out of space, disable receive interrupts
1110 			 * until the queue has drained a bit.
1111 			 */
1112 			if (!cc) {
1113 				SET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED);
1114 				CLR(sc->sc_ctrl, (Ctrl_RIE|Ctrl_RTIE));
1115 				epcom_set(sc);
1116 			}
1117 		} else {
1118 #ifdef DIAGNOSTIC
1119 			panic("epcomintr: we shouldn't reach here");
1120 #endif
1121 			CLR(sc->sc_ctrl, (Ctrl_RIE|Ctrl_RTIE));
1122 			epcom_set(sc);
1123 		}
1124 	}
1125 
1126 	/*
1127 	 * Done handling any receive interrupts. See if data can be
1128 	 * transmitted as well. Schedule tx done event if no data left
1129 	 * and tty was marked busy.
1130 	 */
1131 
1132 	if (!ISSET(flagr, Flag_TXFF) && sc->sc_tbc > 0) {
1133 		/* Output the next chunk of the contiguous buffer, if any. */
1134 		epcom_filltx(sc);
1135 	} else {
1136 		/* Disable transmit completion interrupts if necessary. */
1137 		if (ISSET(sc->sc_ctrl, Ctrl_TIE)) {
1138 			CLR(sc->sc_ctrl, Ctrl_TIE);
1139 			epcom_set(sc);
1140 		}
1141 		if (sc->sc_tx_busy) {
1142 			sc->sc_tx_busy = 0;
1143 			sc->sc_tx_done = 1;
1144 		}
1145 	}
1146 
1147 	/* Wake up the poller. */
1148 	softintr_schedule(sc->sc_si);
1149 
1150 #if 0 /* XXX: broken */
1151 #if NRND > 0 && defined(RND_COM)
1152 	rnd_add_uint32(&sc->rnd_source, intr ^ flagr);
1153 #endif
1154 #endif
1155 	return (1);
1156 }
1157