xref: /netbsd-src/sys/arch/arm/ep93xx/epcom.c (revision 82d56013d7b633d116a93943de88e08335357a7c)
1 /*	$NetBSD: epcom.c,v 1.32 2020/11/20 18:03:52 thorpej 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  *
27  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
28  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
29  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
30  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
31  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
32  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
33  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
34  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
35  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
36  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
37  * POSSIBILITY OF SUCH DAMAGE.
38  */
39 
40 /*
41  * Copyright (c) 1991 The Regents of the University of California.
42  * All rights reserved.
43  *
44  * Redistribution and use in source and binary forms, with or without
45  * modification, are permitted provided that the following conditions
46  * are met:
47  * 1. Redistributions of source code must retain the above copyright
48  *    notice, this list of conditions and the following disclaimer.
49  * 2. Redistributions in binary form must reproduce the above copyright
50  *    notice, this list of conditions and the following disclaimer in the
51  *    documentation and/or other materials provided with the distribution.
52  * 3. Neither the name of the University nor the names of its contributors
53  *    may be used to endorse or promote products derived from this software
54  *    without specific prior written permission.
55  *
56  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
57  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
58  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
59  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
60  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
61  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
62  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
63  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
64  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
65  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
66  * SUCH DAMAGE.
67  *
68  *      @(#)com.c       7.5 (Berkeley) 5/16/91
69  */
70 
71 /*
72  * TODO: hardware flow control
73  */
74 
75 #include <sys/cdefs.h>
76 __KERNEL_RCSID(0, "$NetBSD: epcom.c,v 1.32 2020/11/20 18:03:52 thorpej Exp $");
77 
78 #include "opt_ddb.h"
79 #include "opt_kgdb.h"
80 #include "epcom.h"
81 
82 #ifdef RND_COM
83 #include <sys/rndsource.h>
84 #endif
85 
86 /*
87  * Override cnmagic(9) macro before including <sys/systm.h>.
88  * We need to know if cn_check_magic triggered debugger, so set a flag.
89  * Callers of cn_check_magic must declare int cn_trapped = 0;
90  * XXX: this is *ugly*!
91  */
92 #define cn_trap()				\
93 	do {					\
94 		console_debugger();		\
95 		cn_trapped = 1;			\
96 	} while (/* CONSTCOND */ 0)
97 
98 
99 #include <sys/param.h>
100 #include <sys/systm.h>
101 #include <sys/types.h>
102 #include <sys/conf.h>
103 #include <sys/file.h>
104 #include <sys/device.h>
105 #include <sys/kernel.h>
106 #include <sys/kmem.h>
107 #include <sys/tty.h>
108 #include <sys/uio.h>
109 #include <sys/vnode.h>
110 #include <sys/kauth.h>
111 
112 #include <machine/intr.h>
113 #include <sys/bus.h>
114 
115 #include <arm/ep93xx/epcomreg.h>
116 #include <arm/ep93xx/epcomvar.h>
117 #include <arm/ep93xx/ep93xxreg.h>
118 #include <arm/ep93xx/ep93xxvar.h>
119 
120 #include <dev/cons.h>
121 
122 static int	epcomparam(struct tty *, struct termios *);
123 static void	epcomstart(struct tty *);
124 static int	epcomhwiflow(struct tty *, int);
125 
126 static u_int	cflag2lcrhi(tcflag_t);
127 static void	epcom_iflush(struct epcom_softc *);
128 static void	epcom_set(struct epcom_softc *);
129 
130 int             epcomcngetc(dev_t);
131 void            epcomcnputc(dev_t, int);
132 void            epcomcnpollc(dev_t, int);
133 
134 static void	epcomsoft(void* arg);
135 inline static void	epcom_txsoft(struct epcom_softc *, struct tty *);
136 inline static void	epcom_rxsoft(struct epcom_softc *, struct tty *);
137 
138 void            epcomcnprobe(struct consdev *);
139 void            epcomcninit(struct consdev *);
140 
141 static struct epcom_cons_softc {
142 	bus_space_tag_t		sc_iot;
143 	bus_space_handle_t	sc_ioh;
144 	bus_addr_t		sc_hwbase;
145 	int			sc_ospeed;
146 	tcflag_t		sc_cflag;
147 	int			sc_attached;
148 } epcomcn_sc;
149 
150 static struct cnm_state epcom_cnm_state;
151 
152 extern struct cfdriver epcom_cd;
153 
154 dev_type_open(epcomopen);
155 dev_type_close(epcomclose);
156 dev_type_read(epcomread);
157 dev_type_write(epcomwrite);
158 dev_type_ioctl(epcomioctl);
159 dev_type_stop(epcomstop);
160 dev_type_tty(epcomtty);
161 dev_type_poll(epcompoll);
162 
163 const struct cdevsw epcom_cdevsw = {
164 	.d_open = epcomopen,
165 	.d_close = epcomclose,
166 	.d_read = epcomread,
167 	.d_write = epcomwrite,
168 	.d_ioctl = epcomioctl,
169 	.d_stop = epcomstop,
170 	.d_tty = epcomtty,
171 	.d_poll = epcompoll,
172 	.d_mmap = nommap,
173 	.d_kqfilter = ttykqfilter,
174 	.d_discard = nodiscard,
175 	.d_flag = D_TTY
176 };
177 
178 struct consdev epcomcons = {
179 	NULL, NULL, epcomcngetc, epcomcnputc, epcomcnpollc, NULL,
180 	NULL, NULL, NODEV, CN_NORMAL
181 };
182 
183 #ifndef DEFAULT_COMSPEED
184 #define DEFAULT_COMSPEED 115200
185 #endif
186 
187 #define COMUNIT(x)	TTUNIT(x)
188 #define COMDIALOUT(x)	TTDIALOUT(x)
189 
190 #define COM_ISALIVE(sc)	((sc)->enabled != 0 && \
191 			device_is_active((sc)->sc_dev))
192 
193 void
194 epcom_attach_subr(struct epcom_softc *sc)
195 {
196 	struct tty *tp;
197 
198 	if (sc->sc_iot == epcomcn_sc.sc_iot
199 	    && sc->sc_hwbase == epcomcn_sc.sc_hwbase) {
200 		epcomcn_sc.sc_attached = 1;
201 		sc->sc_lcrlo = EPCOMSPEED2BRD(epcomcn_sc.sc_ospeed) & 0xff;
202 		sc->sc_lcrmid = EPCOMSPEED2BRD(epcomcn_sc.sc_ospeed) >> 8;
203 
204 		/* Make sure the console is always "hardwired". */
205 		delay(10000);	/* wait for output to finish */
206 		SET(sc->sc_hwflags, COM_HW_CONSOLE);
207 		SET(sc->sc_swflags, TIOCFLAG_SOFTCAR);
208 	}
209 
210 	tp = tty_alloc();
211 	tp->t_oproc = epcomstart;
212 	tp->t_param = epcomparam;
213 	tp->t_hwiflow = epcomhwiflow;
214 
215 	sc->sc_tty = tp;
216 	sc->sc_rbuf = kmem_alloc(EPCOM_RING_SIZE << 1, KM_SLEEP);
217 	sc->sc_rbput = sc->sc_rbget = sc->sc_rbuf;
218 	sc->sc_rbavail = EPCOM_RING_SIZE;
219 	sc->sc_ebuf = sc->sc_rbuf + (EPCOM_RING_SIZE << 1);
220 	sc->sc_tbc = 0;
221 
222 	sc->sc_lcrlo = EPCOMSPEED2BRD(DEFAULT_COMSPEED) & 0xff;
223 	sc->sc_lcrmid = EPCOMSPEED2BRD(DEFAULT_COMSPEED) >> 8;
224 	sc->sc_lcrhi = cflag2lcrhi(CS8); /* 8N1 */
225 
226 	tty_attach(tp);
227 
228 	if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
229 		int maj;
230 
231 		/* locate the major number */
232 		maj = cdevsw_lookup_major(&epcom_cdevsw);
233 
234 		cn_tab->cn_dev = makedev(maj, device_unit(sc->sc_dev));
235 
236 		aprint_normal("%s: console\n", device_xname(sc->sc_dev));
237 	}
238 
239 	sc->sc_si = softint_establish(SOFTINT_SERIAL, epcomsoft, sc);
240 
241 #ifdef RND_COM
242 	rnd_attach_source(&sc->rnd_source, device_xname(sc->sc_dev),
243 			  RND_TYPE_TTY, RND_FLAG_DEFAULT);
244 #endif
245 
246 	/* if there are no enable/disable functions, assume the device
247 	   is always enabled */
248 	if (!sc->enable)
249 		sc->enabled = 1;
250 
251 	/* XXX configure register */
252 	/* xxx_config(sc) */
253 
254 	SET(sc->sc_hwflags, COM_HW_DEV_OK);
255 }
256 
257 static int
258 epcomparam(struct tty *tp, struct termios *t)
259 {
260 	struct epcom_softc *sc
261 		= device_lookup_private(&epcom_cd, COMUNIT(tp->t_dev));
262 	int s;
263 
264 	if (COM_ISALIVE(sc) == 0)
265 		return (EIO);
266 
267 	if (t->c_ispeed && t->c_ispeed != t->c_ospeed)
268 		return (EINVAL);
269 
270 	/*
271 	 * For the console, always force CLOCAL and !HUPCL, so that the port
272 	 * is always active.
273 	 */
274 	if (ISSET(sc->sc_swflags, TIOCFLAG_SOFTCAR) ||
275 	    ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
276 		SET(t->c_cflag, CLOCAL);
277 		CLR(t->c_cflag, HUPCL);
278 	}
279 
280 	/*
281 	 * If there were no changes, don't do anything.  This avoids dropping
282 	 * input and improves performance when all we did was frob things like
283 	 * VMIN and VTIME.
284 	 */
285 	if (tp->t_ospeed == t->c_ospeed &&
286 	    tp->t_cflag == t->c_cflag)
287 		return (0);
288 
289 	s = splserial();
290 
291 	sc->sc_lcrhi = cflag2lcrhi(t->c_cflag);
292 	sc->sc_lcrlo = EPCOMSPEED2BRD(t->c_ospeed) & 0xff;
293 	sc->sc_lcrmid = EPCOMSPEED2BRD(t->c_ospeed) >> 8;
294 
295 	/* And copy to tty. */
296 	tp->t_ispeed = 0;
297 	tp->t_ospeed = t->c_ospeed;
298 	tp->t_cflag = t->c_cflag;
299 	epcom_set(sc);
300 
301 	splx(s);
302 
303 	/*
304 	 * Update the tty layer's idea of the carrier bit.
305 	 * We tell tty the carrier is always on.
306 	 */
307 	(void) (*tp->t_linesw->l_modem)(tp, 1);
308 
309 #ifdef COM_DEBUG
310 	if (com_debug)
311 		comstatus(sc, "comparam ");
312 #endif
313 
314 	if (!ISSET(t->c_cflag, CHWFLOW)) {
315 		if (sc->sc_tx_stopped) {
316 			sc->sc_tx_stopped = 0;
317 			epcomstart(tp);
318 		}
319 	}
320 
321 	return (0);
322 }
323 
324 static int
325 epcomhwiflow(struct tty *tp, int block)
326 {
327 	return (0);
328 }
329 
330 static void
331 epcom_filltx(struct epcom_softc *sc)
332 {
333 	bus_space_tag_t iot = sc->sc_iot;
334 	bus_space_handle_t ioh = sc->sc_ioh;
335 	int n;
336 
337 	n = 0;
338         while ((bus_space_read_4(iot, ioh, EPCOM_Flag) & Flag_TXFF) == 0) {
339 		if (n >= sc->sc_tbc)
340 			break;
341 		bus_space_write_4(iot, ioh, EPCOM_Data,
342 				  0xff & *(sc->sc_tba + n));
343 		n++;
344         }
345         sc->sc_tbc -= n;
346         sc->sc_tba += n;
347 }
348 
349 static void
350 epcomstart(struct tty *tp)
351 {
352 	struct epcom_softc *sc
353 		= device_lookup_private(&epcom_cd, COMUNIT(tp->t_dev));
354 	int s;
355 
356 	if (COM_ISALIVE(sc) == 0)
357 		return;
358 
359 	s = spltty();
360 	if (ISSET(tp->t_state, TS_BUSY | TS_TIMEOUT | TS_TTSTOP))
361 		goto out;
362 	if (sc->sc_tx_stopped)
363 		goto out;
364 	if (!ttypull(tp))
365 		goto out;
366 
367 	/* Grab the first contiguous region of buffer space. */
368 	{
369 		u_char *tba;
370 		int tbc;
371 
372 		tba = tp->t_outq.c_cf;
373 		tbc = ndqb(&tp->t_outq, 0);
374 
375 		(void)splserial();
376 
377 		sc->sc_tba = tba;
378 		sc->sc_tbc = tbc;
379 	}
380 
381 	SET(tp->t_state, TS_BUSY);
382 	sc->sc_tx_busy = 1;
383 
384 	/* Output the first chunk of the contiguous buffer. */
385 	epcom_filltx(sc);
386 
387 	if (!ISSET(sc->sc_ctrl, Ctrl_TIE)) {
388 		SET(sc->sc_ctrl, Ctrl_TIE);
389 		epcom_set(sc);
390 	}
391 
392 out:
393 	splx(s);
394 	return;
395 }
396 
397 static void
398 epcom_break(struct epcom_softc *sc, int onoff)
399 {
400 	if (onoff)
401 		SET(sc->sc_lcrhi, LinCtrlHigh_BRK);
402 	else
403 		CLR(sc->sc_lcrhi, LinCtrlHigh_BRK);
404 	epcom_set(sc);
405 }
406 
407 static void
408 epcom_shutdown(struct epcom_softc *sc)
409 {
410 	int s;
411 
412 	s = splserial();
413 
414 	/* Turn off interrupts. */
415 	CLR(sc->sc_ctrl, (Ctrl_TIE|Ctrl_RTIE|Ctrl_RIE));
416 
417 	/* Clear any break condition set with TIOCSBRK. */
418 	epcom_break(sc, 0);
419 	epcom_set(sc);
420 
421 	if (sc->disable) {
422 #ifdef DIAGNOSTIC
423 		if (!sc->enabled)
424 			panic("epcom_shutdown: not enabled?");
425 #endif
426 		(*sc->disable)(sc);
427 		sc->enabled = 0;
428 	}
429 	splx(s);
430 }
431 
432 int
433 epcomopen(dev_t dev, int flag, int mode, struct lwp *l)
434 {
435 	struct epcom_softc *sc;
436 	struct tty *tp;
437 	int s, s2;
438 	int error;
439 
440 	sc = device_lookup_private(&epcom_cd, COMUNIT(dev));
441 	if (sc == NULL || !ISSET(sc->sc_hwflags, COM_HW_DEV_OK) ||
442 		sc->sc_rbuf == NULL)
443 		return (ENXIO);
444 
445 	if (!device_is_active(sc->sc_dev))
446 		return (ENXIO);
447 
448 #ifdef KGDB
449 	/*
450 	 * If this is the kgdb port, no other use is permitted.
451 	 */
452 	if (ISSET(sc->sc_hwflags, COM_HW_KGDB))
453 		return (EBUSY);
454 #endif
455 
456 	tp = sc->sc_tty;
457 
458 	if (kauth_authorize_device_tty(l->l_cred, KAUTH_DEVICE_TTY_OPEN, tp))
459 		return (EBUSY);
460 
461 	s = spltty();
462 
463 	/*
464 	 * Do the following iff this is a first open.
465 	 */
466 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
467 		struct termios t;
468 
469 		tp->t_dev = dev;
470 
471 		s2 = splserial();
472 
473 		if (sc->enable) {
474 			if ((*sc->enable)(sc)) {
475 				splx(s2);
476 				splx(s);
477 				printf("%s: device enable failed\n",
478 				       device_xname(sc->sc_dev));
479 				return (EIO);
480 			}
481 			sc->enabled = 1;
482 #if 0
483 /* XXXXXXXXXXXXXXX */
484 			com_config(sc);
485 #endif
486 		}
487 
488 		/* Turn on interrupts. */
489 		SET(sc->sc_ctrl, (Ctrl_UARTE|Ctrl_RIE|Ctrl_RTIE));
490 		epcom_set(sc);
491 
492 #if 0
493 		/* Fetch the current modem control status, needed later. */
494 		sc->sc_msr = bus_space_read_1(sc->sc_iot, sc->sc_ioh, com_msr);
495 
496 		/* Clear PPS capture state on first open. */
497 		sc->sc_ppsmask = 0;
498 		sc->ppsparam.mode = 0;
499 #endif
500 
501 		splx(s2);
502 
503 		/*
504 		 * Initialize the termios status to the defaults.  Add in the
505 		 * sticky bits from TIOCSFLAGS.
506 		 */
507 		t.c_ispeed = 0;
508 		if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
509 			t.c_ospeed = epcomcn_sc.sc_ospeed;
510 			t.c_cflag = epcomcn_sc.sc_cflag;
511 		} else {
512 			t.c_ospeed = TTYDEF_SPEED;
513 			t.c_cflag = TTYDEF_CFLAG;
514 		}
515 		if (ISSET(sc->sc_swflags, TIOCFLAG_CLOCAL))
516 			SET(t.c_cflag, CLOCAL);
517 		if (ISSET(sc->sc_swflags, TIOCFLAG_CRTSCTS))
518 			SET(t.c_cflag, CRTSCTS);
519 		if (ISSET(sc->sc_swflags, TIOCFLAG_MDMBUF))
520 			SET(t.c_cflag, MDMBUF);
521 		/* Make sure epcomparam() will do something. */
522 		tp->t_ospeed = 0;
523 		(void) epcomparam(tp, &t);
524 		tp->t_iflag = TTYDEF_IFLAG;
525 		tp->t_oflag = TTYDEF_OFLAG;
526 		tp->t_lflag = TTYDEF_LFLAG;
527 		ttychars(tp);
528 		ttsetwater(tp);
529 
530 		s2 = splserial();
531 
532 		/* Clear the input ring, and unblock. */
533 		sc->sc_rbput = sc->sc_rbget = sc->sc_rbuf;
534 		sc->sc_rbavail = EPCOM_RING_SIZE;
535 		epcom_iflush(sc);
536 		CLR(sc->sc_rx_flags, RX_ANY_BLOCK);
537 
538 #ifdef COM_DEBUG
539 		if (epcom_debug)
540 			comstatus(sc, "epcomopen  ");
541 #endif
542 
543 		splx(s2);
544 	}
545 
546 	splx(s);
547 
548 	error = ttyopen(tp, COMDIALOUT(dev), ISSET(flag, O_NONBLOCK));
549 	if (error)
550 		goto bad;
551 
552 	error = (*tp->t_linesw->l_open)(dev, tp);
553 	if (error)
554 		goto bad;
555 
556 	return (0);
557 
558 bad:
559 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
560 		/*
561 		 * We failed to open the device, and nobody else had it opened.
562 		 * Clean up the state as appropriate.
563 		 */
564 		epcom_shutdown(sc);
565 	}
566 
567 	return (error);
568 }
569 
570 int
571 epcomclose(dev_t dev, int flag, int mode, struct lwp *l)
572 {
573 	struct epcom_softc *sc = device_lookup_private(&epcom_cd, COMUNIT(dev));
574 	struct tty *tp = sc->sc_tty;
575 
576 	/* XXX This is for cons.c. */
577 	if (!ISSET(tp->t_state, TS_ISOPEN))
578 		return (0);
579 
580 	(*tp->t_linesw->l_close)(tp, flag);
581 	ttyclose(tp);
582 
583 	if (COM_ISALIVE(sc) == 0)
584 		return (0);
585 
586 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
587 		/*
588 		 * Although we got a last close, the device may still be in
589 		 * use; e.g. if this was the dialout node, and there are still
590 		 * processes waiting for carrier on the non-dialout node.
591 		 */
592 		epcom_shutdown(sc);
593 	}
594 
595 	return (0);
596 }
597 
598 int
599 epcomread(dev_t dev, struct uio *uio, int flag)
600 {
601 	struct epcom_softc *sc = device_lookup_private(&epcom_cd, COMUNIT(dev));
602 	struct tty *tp = sc->sc_tty;
603 
604 	if (COM_ISALIVE(sc) == 0)
605 		return (EIO);
606 
607 	return ((*tp->t_linesw->l_read)(tp, uio, flag));
608 }
609 
610 int
611 epcomwrite(dev_t dev, struct uio *uio, int flag)
612 {
613 	struct epcom_softc *sc = device_lookup_private(&epcom_cd, COMUNIT(dev));
614 	struct tty *tp = sc->sc_tty;
615 
616 	if (COM_ISALIVE(sc) == 0)
617 		return (EIO);
618 
619 	return ((*tp->t_linesw->l_write)(tp, uio, flag));
620 }
621 
622 int
623 epcompoll(dev_t dev, int events, struct lwp *l)
624 {
625 	struct epcom_softc *sc = device_lookup_private(&epcom_cd, COMUNIT(dev));
626 	struct tty *tp = sc->sc_tty;
627 
628 	if (COM_ISALIVE(sc) == 0)
629 		return (EIO);
630 
631 	return ((*tp->t_linesw->l_poll)(tp, events, l));
632 }
633 
634 struct tty *
635 epcomtty(dev_t dev)
636 {
637 	struct epcom_softc *sc = device_lookup_private(&epcom_cd, COMUNIT(dev));
638 	struct tty *tp = sc->sc_tty;
639 
640 	return (tp);
641 }
642 
643 int
644 epcomioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l)
645 {
646 	struct epcom_softc *sc = device_lookup_private(&epcom_cd, COMUNIT(dev));
647 	struct tty *tp = sc->sc_tty;
648 	int error;
649 	int s;
650 
651 	if (COM_ISALIVE(sc) == 0)
652 		return (EIO);
653 
654 	error = (*tp->t_linesw->l_ioctl)(tp, cmd, data, flag, l);
655 	if (error != EPASSTHROUGH)
656 		return (error);
657 
658 	error = ttioctl(tp, cmd, data, flag, l);
659 	if (error != EPASSTHROUGH)
660 		return (error);
661 
662 	error = 0;
663 
664 	s = splserial();
665 
666 	switch (cmd) {
667 	case TIOCSBRK:
668 		epcom_break(sc, 1);
669 		break;
670 
671 	case TIOCCBRK:
672 		epcom_break(sc, 0);
673 		break;
674 
675 	case TIOCGFLAGS:
676 		*(int *)data = sc->sc_swflags;
677 		break;
678 
679 	case TIOCSFLAGS:
680 		error = kauth_authorize_device_tty(l->l_cred,
681 		    KAUTH_DEVICE_TTY_PRIVSET, tp);
682 		if (error)
683 			break;
684 		sc->sc_swflags = *(int *)data;
685 		break;
686 
687 	default:
688 		error = EPASSTHROUGH;
689 		break;
690 	}
691 
692 	splx(s);
693 
694 	return (error);
695 }
696 
697 /*
698  * Stop output on a line.
699  */
700 void
701 epcomstop(struct tty *tp, int flag)
702 {
703 	struct epcom_softc *sc
704 		= device_lookup_private(&epcom_cd, COMUNIT(tp->t_dev));
705 	int s;
706 
707 	s = splserial();
708 	if (ISSET(tp->t_state, TS_BUSY)) {
709 		/* Stop transmitting at the next chunk. */
710 		sc->sc_tbc = 0;
711 		if (!ISSET(tp->t_state, TS_TTSTOP))
712 			SET(tp->t_state, TS_FLUSH);
713 	}
714 	splx(s);
715 }
716 
717 static u_int
718 cflag2lcrhi(tcflag_t cflag)
719 {
720 	u_int lcrhi;
721 
722 	switch (cflag & CSIZE) {
723 	case CS7:
724 		lcrhi = 0x40;
725 		break;
726 	case CS6:
727 		lcrhi = 0x20;
728 		break;
729 	case CS8:
730 	default:
731 		lcrhi = 0x60;
732 		break;
733 	}
734 	lcrhi |= (cflag & PARENB) ? LinCtrlHigh_PEN : 0;
735 	lcrhi |= (cflag & PARODD) ? 0 : LinCtrlHigh_EPS;
736 	lcrhi |= (cflag & CSTOPB) ? LinCtrlHigh_STP2 : 0;
737 	lcrhi |= LinCtrlHigh_FEN;  /* FIFO always enabled */
738 
739 	return (lcrhi);
740 }
741 
742 static void
743 epcom_iflush(struct epcom_softc *sc)
744 {
745 	bus_space_tag_t iot = sc->sc_iot;
746 	bus_space_handle_t ioh = sc->sc_ioh;
747 #ifdef DIAGNOSTIC
748 	int reg;
749 #endif
750 	int timo;
751 
752 #ifdef DIAGNOSTIC
753 	reg = 0xffff;
754 #endif
755 	timo = 50000;
756 	/* flush any pending I/O */
757 	while ((bus_space_read_4(iot, ioh, EPCOM_Flag) & Flag_RXFE) == 0
758 	       && --timo)
759 #ifdef DIAGNOSTIC
760 		reg =
761 #else
762 			(void)
763 #endif
764 			bus_space_read_4(iot, ioh, EPCOM_Data);
765 #ifdef DIAGNOSTIC
766 	if (!timo)
767 		printf("%s: com_iflush timeout %02x\n", device_xname(sc->sc_dev),
768 		       reg);
769 #endif
770 }
771 
772 static void
773 epcom_set(struct epcom_softc *sc)
774 {
775 	bus_space_write_4(sc->sc_iot, sc->sc_ioh, EPCOM_LinCtrlLow,
776 			  sc->sc_lcrlo);
777 	bus_space_write_4(sc->sc_iot, sc->sc_ioh, EPCOM_LinCtrlMid,
778 			  sc->sc_lcrmid);
779 	bus_space_write_4(sc->sc_iot, sc->sc_ioh, EPCOM_LinCtrlHigh,
780 			  sc->sc_lcrhi);
781 	bus_space_write_4(sc->sc_iot, sc->sc_ioh, EPCOM_Ctrl,
782 			  sc->sc_ctrl);
783 }
784 
785 int
786 epcomcnattach(bus_space_tag_t iot, bus_addr_t iobase, bus_space_handle_t ioh,
787     int ospeed, tcflag_t cflag)
788 {
789 	u_int lcrlo, lcrmid, lcrhi, ctrl, pwrcnt;
790 	bus_space_handle_t syscon_ioh;
791 
792 	cn_tab = &epcomcons;
793 	cn_init_magic(&epcom_cnm_state);
794 	cn_set_magic("\047\001");
795 
796 	epcomcn_sc.sc_iot = iot;
797 	epcomcn_sc.sc_ioh = ioh;
798 	epcomcn_sc.sc_hwbase = iobase;
799 	epcomcn_sc.sc_ospeed = ospeed;
800 	epcomcn_sc.sc_cflag = cflag;
801 
802 	lcrhi = cflag2lcrhi(cflag);
803 	lcrlo = EPCOMSPEED2BRD(ospeed) & 0xff;
804 	lcrmid = EPCOMSPEED2BRD(ospeed) >> 8;
805 	ctrl = Ctrl_UARTE;
806 
807 	bus_space_map(iot, EP93XX_APB_HWBASE + EP93XX_APB_SYSCON,
808 		EP93XX_APB_SYSCON_SIZE, 0, &syscon_ioh);
809 	pwrcnt = bus_space_read_4(iot, syscon_ioh, EP93XX_SYSCON_PwrCnt);
810 	pwrcnt &= ~(PwrCnt_UARTBAUD);
811 	bus_space_write_4(iot, syscon_ioh, EP93XX_SYSCON_PwrCnt, pwrcnt);
812 	bus_space_unmap(iot, syscon_ioh, EP93XX_APB_SYSCON_SIZE);
813 
814 	bus_space_write_4(iot, ioh, EPCOM_LinCtrlLow, lcrlo);
815 	bus_space_write_4(iot, ioh, EPCOM_LinCtrlMid, lcrmid);
816 	bus_space_write_4(iot, ioh, EPCOM_LinCtrlHigh, lcrhi);
817 	bus_space_write_4(iot, ioh, EPCOM_Ctrl, ctrl);
818 
819 	return (0);
820 }
821 
822 void
823 epcomcnprobe(struct consdev *cp)
824 {
825 	cp->cn_pri = CN_REMOTE;
826 }
827 
828 void
829 epcomcnpollc(dev_t dev, int on)
830 {
831 }
832 
833 void
834 epcomcnputc(dev_t dev, int c)
835 {
836 	int			s;
837 	bus_space_tag_t		iot = epcomcn_sc.sc_iot;
838 	bus_space_handle_t	ioh = epcomcn_sc.sc_ioh;
839 
840 	s = splserial();
841 
842 	while((bus_space_read_4(iot, ioh, EPCOM_Flag) & Flag_TXFF) != 0)
843 		;
844 
845 	bus_space_write_4(iot, ioh, EPCOM_Data, c);
846 
847 #ifdef DEBUG
848 	if (c == '\r') {
849 		while((bus_space_read_4(iot, ioh, EPCOM_Flag) & Flag_TXFE) == 0)
850 			;
851 	}
852 #endif
853 
854 	splx(s);
855 }
856 
857 int
858 epcomcngetc(dev_t dev)
859 {
860 	int			c, sts;
861 	int			s;
862 	bus_space_tag_t		iot = epcomcn_sc.sc_iot;
863 	bus_space_handle_t	ioh = epcomcn_sc.sc_ioh;
864 
865         s = splserial();
866 
867 	while((bus_space_read_4(iot, ioh, EPCOM_Flag) & Flag_RXFE) != 0)
868 		;
869 
870 	c = bus_space_read_4(iot, ioh, EPCOM_Data);
871 	sts = bus_space_read_4(iot, ioh, EPCOM_RXSts);
872 	if (ISSET(sts, RXSts_BE)) c = CNC_BREAK;
873 #ifdef DDB
874 	extern int db_active;
875 	if (!db_active)
876 #endif
877 	{
878 		int cn_trapped __unused = 0;
879 
880 		cn_check_magic(dev, c, epcom_cnm_state);
881 	}
882 	c &= 0xff;
883 	splx(s);
884 
885 	return (c);
886 }
887 
888 inline static void
889 epcom_txsoft(struct epcom_softc *sc, struct tty *tp)
890 {
891 	CLR(tp->t_state, TS_BUSY);
892 	if (ISSET(tp->t_state, TS_FLUSH))
893 		CLR(tp->t_state, TS_FLUSH);
894         else
895 		ndflush(&tp->t_outq, (int)(sc->sc_tba - tp->t_outq.c_cf));
896 	(*tp->t_linesw->l_start)(tp);
897 }
898 
899 inline static void
900 epcom_rxsoft(struct epcom_softc *sc, struct tty *tp)
901 {
902 	int (*rint)(int, struct tty *) = tp->t_linesw->l_rint;
903 	u_char *get, *end;
904 	u_int cc, scc;
905 	u_char sts;
906 	int code;
907 	int s;
908 
909 	end = sc->sc_ebuf;
910 	get = sc->sc_rbget;
911 	scc = cc = EPCOM_RING_SIZE - sc->sc_rbavail;
912 #if 0
913 	if (cc == EPCOM_RING_SIZE) {
914 		sc->sc_floods++;
915 		if (sc->sc_errors++ == 0)
916 			callout_reset(&sc->sc_diag_callout, 60 * hz,
917 			    comdiag, sc);
918 	}
919 #endif
920 	while (cc) {
921 		code = get[0];
922 		sts = get[1];
923 		if (ISSET(sts, RXSts_OE | RXSts_FE | RXSts_PE | RXSts_BE)) {
924 #if 0
925 			if (ISSET(lsr, DR_ROR)) {
926 				sc->sc_overflows++;
927 				if (sc->sc_errors++ == 0)
928 					callout_reset(&sc->sc_diag_callout,
929 					    60 * hz, comdiag, sc);
930 			}
931 #endif
932 			if (ISSET(sts, (RXSts_FE|RXSts_BE)))
933 				SET(code, TTY_FE);
934 			if (ISSET(sts, RXSts_PE))
935 				SET(code, TTY_PE);
936 		}
937 		if ((*rint)(code, tp) == -1) {
938 			/*
939 			 * The line discipline's buffer is out of space.
940 			 */
941 			if (!ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED)) {
942 				/*
943 				 * We're either not using flow control, or the
944 				 * line discipline didn't tell us to block for
945 				 * some reason.  Either way, we have no way to
946 				 * know when there's more space available, so
947 				 * just drop the rest of the data.
948 				 */
949 				get += cc << 1;
950 				if (get >= end)
951 					get -= EPCOM_RING_SIZE << 1;
952 				cc = 0;
953 			} else {
954 				/*
955 				 * Don't schedule any more receive processing
956 				 * until the line discipline tells us there's
957 				 * space available (through comhwiflow()).
958 				 * Leave the rest of the data in the input
959 				 * buffer.
960 				 */
961 				SET(sc->sc_rx_flags, RX_TTY_OVERFLOWED);
962 			}
963 			break;
964 		}
965 		get += 2;
966 		if (get >= end)
967 			get = sc->sc_rbuf;
968 		cc--;
969 	}
970 
971 	if (cc != scc) {
972 		sc->sc_rbget = get;
973 		s = splserial();
974 
975 		cc = sc->sc_rbavail += scc - cc;
976 		/* Buffers should be ok again, release possible block. */
977 		if (cc >= 1) {
978 			if (ISSET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED)) {
979 				CLR(sc->sc_rx_flags, RX_IBUF_OVERFLOWED);
980 				SET(sc->sc_ctrl, (Ctrl_RIE|Ctrl_RTIE));
981 				epcom_set(sc);
982 			}
983 			if (ISSET(sc->sc_rx_flags, RX_IBUF_BLOCKED)) {
984 				CLR(sc->sc_rx_flags, RX_IBUF_BLOCKED);
985 #if 0
986 				com_hwiflow(sc);
987 #endif
988 			}
989 		}
990 		splx(s);
991 	}
992 }
993 
994 static void
995 epcomsoft(void* arg)
996 {
997 	struct epcom_softc *sc = arg;
998 
999 	if (COM_ISALIVE(sc) == 0)
1000 		return;
1001 
1002 	if (sc->sc_rx_ready) {
1003 		sc->sc_rx_ready = 0;
1004 		epcom_rxsoft(sc, sc->sc_tty);
1005 	}
1006 	if (sc->sc_tx_done) {
1007 		sc->sc_tx_done = 0;
1008 		epcom_txsoft(sc, sc->sc_tty);
1009 	}
1010 }
1011 
1012 int
1013 epcomintr(void* arg)
1014 {
1015 	struct epcom_softc *sc = arg;
1016 	bus_space_tag_t iot = sc->sc_iot;
1017 	bus_space_handle_t ioh = sc->sc_ioh;
1018 	u_char *put, *end;
1019 	u_int cc;
1020 	u_int flagr;
1021 	uint32_t c, csts;
1022 
1023 	(void) bus_space_read_4(iot, ioh, EPCOM_IntIDIntClr);
1024 
1025 	if (COM_ISALIVE(sc) == 0)
1026 		panic("intr on disabled epcom");
1027 
1028 	flagr = bus_space_read_4(iot, ioh, EPCOM_Flag);
1029 
1030 	end = sc->sc_ebuf;
1031 	put = sc->sc_rbput;
1032 	cc = sc->sc_rbavail;
1033 
1034 	if (!(ISSET(flagr, Flag_RXFE))) {
1035 		if (!ISSET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED)) {
1036 			while (cc > 0) {
1037 				if (ISSET(flagr, Flag_RXFE))
1038 					break;
1039 				c = bus_space_read_4(iot, ioh, EPCOM_Data);
1040 				csts = bus_space_read_4(iot, ioh, EPCOM_RXSts);
1041 				if (ISSET(csts, RXSts_BE)) {
1042 					int cn_trapped = 0;
1043 
1044 					cn_check_magic(sc->sc_tty->t_dev,
1045 					  CNC_BREAK, epcom_cnm_state);
1046 					if (cn_trapped)
1047 						goto next;
1048 #if defined(KGDB) && !defined(DDB)
1049 					if (ISSET(sc->sc_hwflags, COM_HW_KGDB)){
1050 						kgdb_connect(1);
1051 						goto next;
1052 					}
1053 #endif
1054 				} else {
1055 					int cn_trapped = 0;
1056 
1057 					cn_check_magic(sc->sc_tty->t_dev,
1058 					  (c & 0xff), epcom_cnm_state);
1059 					if (cn_trapped)
1060 						goto next;
1061 				}
1062 
1063 
1064 				put[0] = c & 0xff;
1065 				put[1] = csts & 0xf;
1066 				put += 2;
1067 				if (put >= end)
1068 					put = sc->sc_rbuf;
1069 				cc--;
1070 			next:
1071 				flagr = bus_space_read_4(iot, ioh, EPCOM_Flag);
1072 			}
1073 
1074 			/*
1075 			 * Current string of incoming characters ended because
1076 			 * no more data was available or we ran out of space.
1077 			 * Schedule a receive event if any data was received.
1078 			 * If we're out of space, turn off receive interrupts.
1079 			 */
1080 			sc->sc_rbput = put;
1081 			sc->sc_rbavail = cc;
1082 			if (!ISSET(sc->sc_rx_flags, RX_TTY_OVERFLOWED))
1083 				sc->sc_rx_ready = 1;
1084 
1085 			/*
1086 			 * See if we are in danger of overflowing a buffer. If
1087 			 * so, use hardware flow control to ease the pressure.
1088 			 */
1089 
1090 			/* but epcom cannot. X-( */
1091 
1092 			/*
1093 			 * If we're out of space, disable receive interrupts
1094 			 * until the queue has drained a bit.
1095 			 */
1096 			if (!cc) {
1097 				SET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED);
1098 				CLR(sc->sc_ctrl, (Ctrl_RIE|Ctrl_RTIE));
1099 				epcom_set(sc);
1100 			}
1101 		} else {
1102 #ifdef DIAGNOSTIC
1103 			panic("epcomintr: we shouldn't reach here");
1104 #endif
1105 			CLR(sc->sc_ctrl, (Ctrl_RIE|Ctrl_RTIE));
1106 			epcom_set(sc);
1107 		}
1108 	}
1109 
1110 	/*
1111 	 * Done handling any receive interrupts. See if data can be
1112 	 * transmitted as well. Schedule tx done event if no data left
1113 	 * and tty was marked busy.
1114 	 */
1115 
1116 	if (!ISSET(flagr, Flag_TXFF) && sc->sc_tbc > 0) {
1117 		/* Output the next chunk of the contiguous buffer, if any. */
1118 		epcom_filltx(sc);
1119 	} else {
1120 		/* Disable transmit completion interrupts if necessary. */
1121 		if (ISSET(sc->sc_ctrl, Ctrl_TIE)) {
1122 			CLR(sc->sc_ctrl, Ctrl_TIE);
1123 			epcom_set(sc);
1124 		}
1125 		if (sc->sc_tx_busy) {
1126 			sc->sc_tx_busy = 0;
1127 			sc->sc_tx_done = 1;
1128 		}
1129 	}
1130 
1131 	/* Wake up the poller. */
1132 	softint_schedule(sc->sc_si);
1133 
1134 #if 0 /* XXX: broken */
1135 #ifdef RND_COM
1136 	rnd_add_uint32(&sc->rnd_source, intr ^ flagr);
1137 #endif
1138 #endif
1139 	return (1);
1140 }
1141