xref: /openbsd/sys/dev/ic/com.c (revision 0f9e9ec2)
1 /*	$OpenBSD: com.c,v 1.179 2024/05/13 01:15:50 jsg Exp $	*/
2 /*	$NetBSD: com.c,v 1.82.4.1 1996/06/02 09:08:00 mrg Exp $	*/
3 
4 /*
5  * Copyright (c) 1997 - 1999, Jason Downs.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS
17  * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
18  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
19  * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT,
20  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
21  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
22  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
23  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 /*-
29  * Copyright (c) 1993, 1994, 1995, 1996
30  *	Charles M. Hannum.  All rights reserved.
31  * Copyright (c) 1991 The Regents of the University of California.
32  * All rights reserved.
33  *
34  * Redistribution and use in source and binary forms, with or without
35  * modification, are permitted provided that the following conditions
36  * are met:
37  * 1. Redistributions of source code must retain the above copyright
38  *    notice, this list of conditions and the following disclaimer.
39  * 2. Redistributions in binary form must reproduce the above copyright
40  *    notice, this list of conditions and the following disclaimer in the
41  *    documentation and/or other materials provided with the distribution.
42  * 3. Neither the name of the University nor the names of its contributors
43  *    may be used to endorse or promote products derived from this software
44  *    without specific prior written permission.
45  *
46  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
47  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
48  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
49  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
50  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
51  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
52  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
53  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
54  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
55  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
56  * SUCH DAMAGE.
57  *
58  *	@(#)com.c	7.5 (Berkeley) 5/16/91
59  */
60 
61 /*
62  * COM driver, based on HP dca driver
63  * uses National Semiconductor NS16450/NS16550AF UART
64  */
65 #include <sys/param.h>
66 #include <sys/systm.h>
67 #include <sys/ioctl.h>
68 #include <sys/tty.h>
69 #include <sys/conf.h>
70 #include <sys/fcntl.h>
71 #include <sys/uio.h>
72 #include <sys/kernel.h>
73 #include <sys/syslog.h>
74 #include <sys/device.h>
75 #include <sys/vnode.h>
76 #ifdef DDB
77 #include <ddb/db_var.h>
78 #endif
79 
80 #include <machine/bus.h>
81 #include <machine/intr.h>
82 
83 #define	COM_CONSOLE
84 #include <dev/cons.h>
85 
86 #include <dev/ic/comreg.h>
87 #include <dev/ic/comvar.h>
88 #include <dev/ic/ns16550reg.h>
89 #define	com_lcr	com_cfcr
90 
91 cdev_decl(com);
92 
93 static u_char tiocm_xxx2mcr(int);
94 
95 void	compwroff(struct com_softc *);
96 void	cominit(bus_space_tag_t, bus_space_handle_t, int, int);
97 
98 struct cfdriver com_cd = {
99 	NULL, "com", DV_TTY
100 };
101 
102 int	comdefaultrate = TTYDEF_SPEED;
103 #ifdef COM_CONSOLE
104 int	comconsfreq;
105 int	comconsrate = TTYDEF_SPEED;
106 bus_addr_t comconsaddr = 0;
107 int	comconsattached;
108 bus_space_tag_t comconsiot;
109 bus_space_handle_t comconsioh;
110 int	comconsunit;
111 tcflag_t comconscflag = TTYDEF_CFLAG;
112 #endif
113 
114 int	commajor;
115 
116 #define	DEVUNIT(x)	(minor(x) & 0x7f)
117 #define	DEVCUA(x)	(minor(x) & 0x80)
118 
119 int
comspeed(long freq,long speed)120 comspeed(long freq, long speed)
121 {
122 #define	divrnd(n, q)	(((n)*2/(q)+1)/2)	/* divide and round off */
123 
124 	int x, err;
125 
126 	if (speed == 0)
127 		return 0;
128 	if (speed < 0)
129 		return -1;
130 	x = divrnd((freq / 16), speed);
131 	if (x <= 0)
132 		return -1;
133 	err = divrnd((quad_t)freq * 1000 / 16, speed * x) - 1000;
134 	if (err < 0)
135 		err = -err;
136 	if (err > COM_TOLERANCE)
137 		return -1;
138 	return x;
139 
140 #undef	divrnd
141 }
142 
143 #ifdef COM_CONSOLE
144 int
comprobe1(bus_space_tag_t iot,bus_space_handle_t ioh)145 comprobe1(bus_space_tag_t iot, bus_space_handle_t ioh)
146 {
147 	int i;
148 
149 	/* force access to id reg */
150 	bus_space_write_1(iot, ioh, com_lcr, LCR_8BITS);
151 	bus_space_write_1(iot, ioh, com_iir, 0);
152 	for (i = 0; i < 32; i++) {
153 		if ((bus_space_read_1(iot, ioh, com_lcr) != LCR_8BITS) ||
154 		    (bus_space_read_1(iot, ioh, com_iir) & 0x38)) {
155 			bus_space_read_1(iot, ioh, com_data); /* cleanup */
156 		} else
157 			break;
158 	}
159 	if (i >= 32)
160 		return 0;
161 
162 	return 1;
163 }
164 #endif
165 
166 int
com_detach(struct device * self,int flags)167 com_detach(struct device *self, int flags)
168 {
169 	struct com_softc *sc = (struct com_softc *)self;
170 	int maj, mn;
171 
172 	sc->sc_swflags |= COM_SW_DEAD;
173 
174 	/* Locate the major number. */
175 	for (maj = 0; maj < nchrdev; maj++)
176 		if (cdevsw[maj].d_open == comopen)
177 			break;
178 
179 	/* Nuke the vnodes for any open instances. */
180 	mn = self->dv_unit;
181 	vdevgone(maj, mn, mn, VCHR);
182 
183 	/* XXX a symbolic constant for the cua bit would be nicer. */
184 	mn |= 0x80;
185 	vdevgone(maj, mn, mn, VCHR);
186 
187 	timeout_del(&sc->sc_dtr_tmo);
188 	timeout_del(&sc->sc_diag_tmo);
189 	softintr_disestablish(sc->sc_si);
190 
191 	/* Detach and free the tty. */
192 	if (sc->sc_tty) {
193 		ttyfree(sc->sc_tty);
194 	}
195 
196 	return (0);
197 }
198 
199 int
com_activate(struct device * self,int act)200 com_activate(struct device *self, int act)
201 {
202 	struct com_softc *sc = (struct com_softc *)self;
203 	int s, rv = 0;
204 
205 	switch (act) {
206 	case DVACT_SUSPEND:
207 		if (timeout_del(&sc->sc_dtr_tmo)) {
208 			/* Make sure DTR gets raised upon resume. */
209 			SET(sc->sc_mcr, MCR_DTR | MCR_RTS);
210 		}
211 		timeout_del(&sc->sc_diag_tmo);
212 		break;
213 	case DVACT_RESUME:
214 		com_resume(sc);
215 		break;
216 	case DVACT_DEACTIVATE:
217 		if (sc->sc_hwflags & COM_HW_CONSOLE) {
218 			rv = EBUSY;
219 			break;
220 		}
221 
222 		s = spltty();
223 		if (sc->disable != NULL && sc->enabled != 0) {
224 			(*sc->disable)(sc);
225 			sc->enabled = 0;
226 		}
227 		splx(s);
228 		break;
229 	}
230 	return (rv);
231 }
232 
233 int
comopen(dev_t dev,int flag,int mode,struct proc * p)234 comopen(dev_t dev, int flag, int mode, struct proc *p)
235 {
236 	int unit = DEVUNIT(dev);
237 	struct com_softc *sc;
238 	struct tty *tp;
239 	int s;
240 	int error = 0;
241 
242 	if (unit >= com_cd.cd_ndevs)
243 		return ENXIO;
244 	sc = com_cd.cd_devs[unit];
245 	if (!sc)
246 		return ENXIO;
247 
248 	s = spltty();
249 	if (!sc->sc_tty) {
250 		tp = sc->sc_tty = ttymalloc(1000000);
251 	} else
252 		tp = sc->sc_tty;
253 	splx(s);
254 
255 	tp->t_oproc = comstart;
256 	tp->t_param = comparam;
257 	tp->t_dev = dev;
258 	if (!ISSET(tp->t_state, TS_ISOPEN)) {
259 		SET(tp->t_state, TS_WOPEN);
260 		ttychars(tp);
261 		tp->t_iflag = TTYDEF_IFLAG;
262 		tp->t_oflag = TTYDEF_OFLAG;
263 #ifdef COM_CONSOLE
264 		if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
265 			tp->t_cflag = comconscflag;
266 			tp->t_ispeed = tp->t_ospeed = comconsrate;
267 		} else
268 #endif
269 		{
270 			tp->t_cflag = TTYDEF_CFLAG;
271 			tp->t_ispeed = tp->t_ospeed = comdefaultrate;
272 		}
273 		if (ISSET(sc->sc_swflags, COM_SW_CLOCAL))
274 			SET(tp->t_cflag, CLOCAL);
275 		if (ISSET(sc->sc_swflags, COM_SW_CRTSCTS))
276 			SET(tp->t_cflag, CRTSCTS);
277 		if (ISSET(sc->sc_swflags, COM_SW_MDMBUF))
278 			SET(tp->t_cflag, MDMBUF);
279 		tp->t_lflag = TTYDEF_LFLAG;
280 
281 		s = spltty();
282 
283 		sc->sc_initialize = 1;
284 		comparam(tp, &tp->t_termios);
285 		ttsetwater(tp);
286 
287 		sc->sc_ibufp = sc->sc_ibuf = sc->sc_ibufs[0];
288 		sc->sc_ibufhigh = sc->sc_ibuf + COM_IHIGHWATER;
289 		sc->sc_ibufend = sc->sc_ibuf + COM_IBUFSIZE;
290 
291 		/*
292 		 * Wake up the sleepy heads.
293 		 */
294 		if (!ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
295 			switch (sc->sc_uarttype) {
296 			case COM_UART_ST16650:
297 			case COM_UART_ST16650V2:
298 				com_write_reg(sc, com_lcr, LCR_EFR);
299 				com_write_reg(sc, com_efr, EFR_ECB);
300 				com_write_reg(sc, com_ier, 0);
301 				com_write_reg(sc, com_efr, 0);
302 				com_write_reg(sc, com_lcr, 0);
303 				break;
304 			case COM_UART_TI16750:
305 				com_write_reg(sc, com_ier, 0);
306 				break;
307 			case COM_UART_XR17V35X:
308 				com_write_reg(sc, UART_EXAR_SLEEP, 0);
309 				break;
310 			}
311 		}
312 
313 		if (ISSET(sc->sc_hwflags, COM_HW_FIFO)) {
314 			u_int8_t fifo = FIFO_ENABLE|FIFO_RCV_RST|FIFO_XMT_RST;
315 			u_int8_t lcr;
316 
317 			if (tp->t_ispeed <= 1200)
318 				fifo |= FIFO_TRIGGER_1;
319 			else if (tp->t_ispeed <= 38400)
320 				fifo |= FIFO_TRIGGER_4;
321 			else
322 				fifo |= FIFO_TRIGGER_8;
323 			if (sc->sc_uarttype == COM_UART_TI16750) {
324 				fifo |= FIFO_ENABLE_64BYTE;
325 				lcr = com_read_reg(sc, com_lcr);
326 				com_write_reg(sc, com_lcr,
327 				    lcr | LCR_DLAB);
328 			}
329 
330 			/*
331 			 * (Re)enable and drain FIFOs.
332 			 *
333 			 * Certain SMC chips cause problems if the FIFOs are
334 			 * enabled while input is ready. Turn off the FIFO
335 			 * if necessary to clear the input. Test the input
336 			 * ready bit after enabling the FIFOs to handle races
337 			 * between enabling and fresh input.
338 			 *
339 			 * Set the FIFO threshold based on the receive speed.
340 			 */
341 			for (;;) {
342 				com_write_reg(sc, com_fifo, 0);
343 				delay(100);
344 				(void) com_read_reg(sc, com_data);
345 				com_write_reg(sc, com_fifo, fifo |
346 				    FIFO_RCV_RST | FIFO_XMT_RST);
347 				delay(100);
348 				if(!ISSET(com_read_reg(sc,
349 				    com_lsr), LSR_RXRDY))
350 					break;
351 			}
352 			if (sc->sc_uarttype == COM_UART_TI16750)
353 				com_write_reg(sc, com_lcr, lcr);
354 		}
355 
356 		/* Flush any pending I/O. */
357 		while (ISSET(com_read_reg(sc, com_lsr), LSR_RXRDY))
358 			(void) com_read_reg(sc, com_data);
359 
360 		/* You turn me on, baby! */
361 		sc->sc_mcr = MCR_DTR | MCR_RTS;
362 		if (!ISSET(sc->sc_hwflags, COM_HW_NOIEN))
363 			SET(sc->sc_mcr, MCR_IENABLE);
364 		com_write_reg(sc, com_mcr, sc->sc_mcr);
365 		sc->sc_ier = IER_ERXRDY | IER_ERLS | IER_EMSC;
366 		com_write_reg(sc, com_ier, sc->sc_ier);
367 
368 		sc->sc_msr = com_read_reg(sc, com_msr);
369 		if (ISSET(sc->sc_swflags, COM_SW_SOFTCAR) || DEVCUA(dev) ||
370 		    ISSET(sc->sc_msr, MSR_DCD) || ISSET(tp->t_cflag, MDMBUF))
371 			SET(tp->t_state, TS_CARR_ON);
372 		else
373 			CLR(tp->t_state, TS_CARR_ON);
374 	} else if (ISSET(tp->t_state, TS_XCLUDE) && suser(p) != 0)
375 		return EBUSY;
376 	else
377 		s = spltty();
378 
379 	if (DEVCUA(dev)) {
380 		if (ISSET(tp->t_state, TS_ISOPEN)) {
381 			/* Ah, but someone already is dialed in... */
382 			splx(s);
383 			return EBUSY;
384 		}
385 		sc->sc_cua = 1;		/* We go into CUA mode. */
386 	} else {
387 		/* tty (not cua) device; wait for carrier if necessary. */
388 		if (ISSET(flag, O_NONBLOCK)) {
389 			if (sc->sc_cua) {
390 				/* Opening TTY non-blocking... but the CUA is busy. */
391 				splx(s);
392 				return EBUSY;
393 			}
394 		} else {
395 			while (sc->sc_cua ||
396 			    (!ISSET(tp->t_cflag, CLOCAL) &&
397 				!ISSET(tp->t_state, TS_CARR_ON))) {
398 				SET(tp->t_state, TS_WOPEN);
399 				error = ttysleep(tp, &tp->t_rawq, TTIPRI | PCATCH, ttopen);
400 				/*
401 				 * If TS_WOPEN has been reset, that means the cua device
402 				 * has been closed.  We don't want to fail in that case,
403 				 * so just go around again.
404 				 */
405 				if (error && ISSET(tp->t_state, TS_WOPEN)) {
406 					CLR(tp->t_state, TS_WOPEN);
407 					if (!sc->sc_cua && !ISSET(tp->t_state, TS_ISOPEN))
408 						compwroff(sc);
409 					splx(s);
410 					return error;
411 				}
412 			}
413 		}
414 	}
415 	splx(s);
416 
417 	return (*linesw[tp->t_line].l_open)(dev, tp, p);
418 }
419 
420 int
comclose(dev_t dev,int flag,int mode,struct proc * p)421 comclose(dev_t dev, int flag, int mode, struct proc *p)
422 {
423 	int unit = DEVUNIT(dev);
424 	struct com_softc *sc = com_cd.cd_devs[unit];
425 	struct tty *tp = sc->sc_tty;
426 	int s;
427 
428 #ifdef COM_CONSOLE
429 	/* XXX This is for cons.c. */
430 	if (!ISSET(tp->t_state, TS_ISOPEN))
431 		return 0;
432 #endif
433 
434 	if(sc->sc_swflags & COM_SW_DEAD)
435 		return 0;
436 
437 	(*linesw[tp->t_line].l_close)(tp, flag, p);
438 	s = spltty();
439 	if (ISSET(tp->t_state, TS_WOPEN)) {
440 		/* tty device is waiting for carrier; drop dtr then re-raise */
441 		CLR(sc->sc_mcr, MCR_DTR | MCR_RTS);
442 		com_write_reg(sc, com_mcr, sc->sc_mcr);
443 		timeout_add_sec(&sc->sc_dtr_tmo, 2);
444 	} else {
445 		/* no one else waiting; turn off the uart */
446 		compwroff(sc);
447 	}
448 	CLR(tp->t_state, TS_BUSY | TS_FLUSH);
449 	sc->sc_cua = 0;
450 	splx(s);
451 	ttyclose(tp);
452 
453 #ifdef COM_CONSOLE
454 #ifdef notyet /* XXXX */
455 	if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
456 		ttyfree(tp);
457 		sc->sc_tty = 0;
458 	}
459 #endif
460 #endif
461 	return 0;
462 }
463 
464 void
compwroff(struct com_softc * sc)465 compwroff(struct com_softc *sc)
466 {
467 	struct tty *tp = sc->sc_tty;
468 
469 	CLR(sc->sc_lcr, LCR_SBREAK);
470 	com_write_reg(sc, com_lcr, sc->sc_lcr);
471 	com_write_reg(sc, com_ier, 0);
472 	if (ISSET(tp->t_cflag, HUPCL) &&
473 	    !ISSET(sc->sc_swflags, COM_SW_SOFTCAR)) {
474 		/* XXX perhaps only clear DTR */
475 		sc->sc_mcr = 0;
476 		com_write_reg(sc, com_mcr, sc->sc_mcr);
477 	}
478 
479 	/*
480 	 * Turn FIFO off; enter sleep mode if possible.
481 	 */
482 	com_write_reg(sc, com_fifo, 0);
483 	delay(100);
484 	if (ISSET(com_read_reg(sc, com_lsr), LSR_RXRDY))
485 		(void) com_read_reg(sc, com_data);
486 	delay(100);
487 	com_write_reg(sc, com_fifo,
488 			  FIFO_RCV_RST | FIFO_XMT_RST);
489 
490 	if (!ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
491 		switch (sc->sc_uarttype) {
492 		case COM_UART_ST16650:
493 		case COM_UART_ST16650V2:
494 			com_write_reg(sc, com_lcr, LCR_EFR);
495 			com_write_reg(sc, com_efr, EFR_ECB);
496 			com_write_reg(sc, com_ier, IER_SLEEP);
497 			com_write_reg(sc, com_lcr, 0);
498 			break;
499 		case COM_UART_TI16750:
500 			com_write_reg(sc, com_ier, IER_SLEEP);
501 			break;
502 		case COM_UART_XR17V35X:
503 			com_write_reg(sc, UART_EXAR_SLEEP, 0xff);
504 			break;
505 		}
506 	}
507 }
508 
509 void
com_resume(struct com_softc * sc)510 com_resume(struct com_softc *sc)
511 {
512 	struct tty *tp = sc->sc_tty;
513 	int ospeed;
514 
515 	if (!tp || !ISSET(tp->t_state, TS_ISOPEN)) {
516 #ifdef COM_CONSOLE
517 		if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE))
518 			cominit(comconsiot, comconsioh, comconsrate,
519 			    comconsfreq);
520 #endif
521 		return;
522 	}
523 
524 	/*
525 	 * Wake up the sleepy heads.
526 	 */
527 	if (!ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
528 		switch (sc->sc_uarttype) {
529 		case COM_UART_ST16650:
530 		case COM_UART_ST16650V2:
531 			com_write_reg(sc, com_lcr, LCR_EFR);
532 			com_write_reg(sc, com_efr, EFR_ECB);
533 			com_write_reg(sc, com_ier, 0);
534 			com_write_reg(sc, com_efr, 0);
535 			com_write_reg(sc, com_lcr, 0);
536 			break;
537 		case COM_UART_TI16750:
538 			com_write_reg(sc, com_ier, 0);
539 			break;
540 		case COM_UART_XR17V35X:
541 			com_write_reg(sc, UART_EXAR_SLEEP, 0);
542 			break;
543 		}
544 	}
545 
546 	ospeed = comspeed(sc->sc_frequency, tp->t_ospeed);
547 
548 	if (ospeed != 0) {
549 		com_write_reg(sc, com_lcr, sc->sc_lcr | LCR_DLAB);
550 		com_write_reg(sc, com_dlbl, ospeed);
551 		com_write_reg(sc, com_dlbh, ospeed >> 8);
552 		com_write_reg(sc, com_lcr, sc->sc_lcr);
553 	} else {
554 		com_write_reg(sc, com_lcr, sc->sc_lcr);
555 	}
556 
557 	if (ISSET(sc->sc_hwflags, COM_HW_FIFO)) {
558 		u_int8_t fifo = FIFO_ENABLE|FIFO_RCV_RST|FIFO_XMT_RST;
559 		u_int8_t lcr;
560 
561 		if (tp->t_ispeed <= 1200)
562 			fifo |= FIFO_TRIGGER_1;
563 		else if (tp->t_ispeed <= 38400)
564 			fifo |= FIFO_TRIGGER_4;
565 		else
566 			fifo |= FIFO_TRIGGER_8;
567 		if (sc->sc_uarttype == COM_UART_TI16750) {
568 			fifo |= FIFO_ENABLE_64BYTE;
569 			lcr = com_read_reg(sc, com_lcr);
570 			com_write_reg(sc, com_lcr,
571 			    lcr | LCR_DLAB);
572 		}
573 
574 		/*
575 		 * (Re)enable and drain FIFOs.
576 		 *
577 		 * Certain SMC chips cause problems if the FIFOs are
578 		 * enabled while input is ready. Turn off the FIFO
579 		 * if necessary to clear the input. Test the input
580 		 * ready bit after enabling the FIFOs to handle races
581 		 * between enabling and fresh input.
582 		 *
583 		 * Set the FIFO threshold based on the receive speed.
584 		 */
585 		for (;;) {
586 			com_write_reg(sc, com_fifo, 0);
587 			delay(100);
588 			(void) com_read_reg(sc, com_data);
589 			com_write_reg(sc, com_fifo, fifo |
590 			    FIFO_RCV_RST | FIFO_XMT_RST);
591 			delay(100);
592 			if(!ISSET(com_read_reg(sc,
593 			    com_lsr), LSR_RXRDY))
594 				break;
595 		}
596 		if (sc->sc_uarttype == COM_UART_TI16750)
597 			com_write_reg(sc, com_lcr, lcr);
598 	}
599 
600 	/* You turn me on, baby! */
601 	com_write_reg(sc, com_mcr, sc->sc_mcr);
602 	com_write_reg(sc, com_ier, sc->sc_ier);
603 }
604 
605 void
com_raisedtr(void * arg)606 com_raisedtr(void *arg)
607 {
608 	struct com_softc *sc = arg;
609 
610 	SET(sc->sc_mcr, MCR_DTR | MCR_RTS);
611 	com_write_reg(sc, com_mcr, sc->sc_mcr);
612 }
613 
614 int
comread(dev_t dev,struct uio * uio,int flag)615 comread(dev_t dev, struct uio *uio, int flag)
616 {
617 	struct com_softc *sc = com_cd.cd_devs[DEVUNIT(dev)];
618 	struct tty *tp = sc->sc_tty;
619 
620 	return ((*linesw[tp->t_line].l_read)(tp, uio, flag));
621 }
622 
623 int
comwrite(dev_t dev,struct uio * uio,int flag)624 comwrite(dev_t dev, struct uio *uio, int flag)
625 {
626 	struct com_softc *sc = com_cd.cd_devs[DEVUNIT(dev)];
627 	struct tty *tp = sc->sc_tty;
628 
629 	return ((*linesw[tp->t_line].l_write)(tp, uio, flag));
630 }
631 
632 struct tty *
comtty(dev_t dev)633 comtty(dev_t dev)
634 {
635 	struct com_softc *sc = com_cd.cd_devs[DEVUNIT(dev)];
636 	struct tty *tp = sc->sc_tty;
637 
638 	return (tp);
639 }
640 
641 static u_char
tiocm_xxx2mcr(int data)642 tiocm_xxx2mcr(int data)
643 {
644 	u_char m = 0;
645 
646 	if (ISSET(data, TIOCM_DTR))
647 		SET(m, MCR_DTR);
648 	if (ISSET(data, TIOCM_RTS))
649 		SET(m, MCR_RTS);
650 	return m;
651 }
652 
653 int
comioctl(dev_t dev,u_long cmd,caddr_t data,int flag,struct proc * p)654 comioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct proc *p)
655 {
656 	int unit = DEVUNIT(dev);
657 	struct com_softc *sc = com_cd.cd_devs[unit];
658 	struct tty *tp = sc->sc_tty;
659 	int error;
660 
661 	error = (*linesw[tp->t_line].l_ioctl)(tp, cmd, data, flag, p);
662 	if (error >= 0)
663 		return error;
664 	error = ttioctl(tp, cmd, data, flag, p);
665 	if (error >= 0)
666 		return error;
667 
668 	switch (cmd) {
669 	case TIOCSBRK:
670 		SET(sc->sc_lcr, LCR_SBREAK);
671 		com_write_reg(sc, com_lcr, sc->sc_lcr);
672 		break;
673 	case TIOCCBRK:
674 		CLR(sc->sc_lcr, LCR_SBREAK);
675 		com_write_reg(sc, com_lcr, sc->sc_lcr);
676 		break;
677 	case TIOCSDTR:
678 		SET(sc->sc_mcr, sc->sc_dtr);
679 		com_write_reg(sc, com_mcr, sc->sc_mcr);
680 		break;
681 	case TIOCCDTR:
682 		CLR(sc->sc_mcr, sc->sc_dtr);
683 		com_write_reg(sc, com_mcr, sc->sc_mcr);
684 		break;
685 	case TIOCMSET:
686 		CLR(sc->sc_mcr, MCR_DTR | MCR_RTS);
687 	case TIOCMBIS:
688 		SET(sc->sc_mcr, tiocm_xxx2mcr(*(int *)data));
689 		com_write_reg(sc, com_mcr, sc->sc_mcr);
690 		break;
691 	case TIOCMBIC:
692 		CLR(sc->sc_mcr, tiocm_xxx2mcr(*(int *)data));
693 		com_write_reg(sc, com_mcr, sc->sc_mcr);
694 		break;
695 	case TIOCMGET: {
696 		u_char m;
697 		int bits = 0;
698 
699 		m = sc->sc_mcr;
700 		if (ISSET(m, MCR_DTR))
701 			SET(bits, TIOCM_DTR);
702 		if (ISSET(m, MCR_RTS))
703 			SET(bits, TIOCM_RTS);
704 		m = sc->sc_msr;
705 		if (ISSET(m, MSR_DCD))
706 			SET(bits, TIOCM_CD);
707 		if (ISSET(m, MSR_CTS))
708 			SET(bits, TIOCM_CTS);
709 		if (ISSET(m, MSR_DSR))
710 			SET(bits, TIOCM_DSR);
711 		if (ISSET(m, MSR_RI | MSR_TERI))
712 			SET(bits, TIOCM_RI);
713 		if (com_read_reg(sc, com_ier))
714 			SET(bits, TIOCM_LE);
715 		*(int *)data = bits;
716 		break;
717 	}
718 	case TIOCGFLAGS: {
719 		int driverbits, userbits = 0;
720 
721 		driverbits = sc->sc_swflags;
722 		if (ISSET(driverbits, COM_SW_SOFTCAR))
723 			SET(userbits, TIOCFLAG_SOFTCAR);
724 		if (ISSET(driverbits, COM_SW_CLOCAL))
725 			SET(userbits, TIOCFLAG_CLOCAL);
726 		if (ISSET(driverbits, COM_SW_CRTSCTS))
727 			SET(userbits, TIOCFLAG_CRTSCTS);
728 		if (ISSET(driverbits, COM_SW_MDMBUF))
729 			SET(userbits, TIOCFLAG_MDMBUF);
730 		if (ISSET(driverbits, COM_SW_PPS))
731 			SET(userbits, TIOCFLAG_PPS);
732 
733 		*(int *)data = userbits;
734 		break;
735 	}
736 	case TIOCSFLAGS: {
737 		int userbits, driverbits = 0;
738 
739 		error = suser(p);
740 		if (error != 0)
741 			return(EPERM);
742 
743 		userbits = *(int *)data;
744 		if (ISSET(userbits, TIOCFLAG_SOFTCAR) ||
745 		    ISSET(sc->sc_hwflags, COM_HW_CONSOLE))
746 			SET(driverbits, COM_SW_SOFTCAR);
747 		if (ISSET(userbits, TIOCFLAG_CLOCAL))
748 			SET(driverbits, COM_SW_CLOCAL);
749 		if (ISSET(userbits, TIOCFLAG_CRTSCTS))
750 			SET(driverbits, COM_SW_CRTSCTS);
751 		if (ISSET(userbits, TIOCFLAG_MDMBUF))
752 			SET(driverbits, COM_SW_MDMBUF);
753 		if (ISSET(userbits, TIOCFLAG_PPS))
754 			SET(driverbits, COM_SW_PPS);
755 
756 		sc->sc_swflags = driverbits;
757 		break;
758 	}
759 	default:
760 		return ENOTTY;
761 	}
762 
763 	return 0;
764 }
765 
766 /* already called at spltty */
767 int
comparam(struct tty * tp,struct termios * t)768 comparam(struct tty *tp, struct termios *t)
769 {
770 	struct com_softc *sc = com_cd.cd_devs[DEVUNIT(tp->t_dev)];
771 	int ospeed = comspeed(sc->sc_frequency, t->c_ospeed);
772 	u_char lcr;
773 	tcflag_t oldcflag;
774 
775 	/* Check requested parameters. */
776 	if (ospeed < 0 || (t->c_ispeed && t->c_ispeed != t->c_ospeed))
777 		return EINVAL;
778 
779 	lcr = ISSET(sc->sc_lcr, LCR_SBREAK);
780 
781 	switch (ISSET(t->c_cflag, CSIZE)) {
782 	case CS5:
783 		SET(lcr, LCR_5BITS);
784 		break;
785 	case CS6:
786 		SET(lcr, LCR_6BITS);
787 		break;
788 	case CS7:
789 		SET(lcr, LCR_7BITS);
790 		break;
791 	case CS8:
792 		SET(lcr, LCR_8BITS);
793 		break;
794 	}
795 	if (ISSET(t->c_cflag, PARENB)) {
796 		SET(lcr, LCR_PENAB);
797 		if (!ISSET(t->c_cflag, PARODD))
798 			SET(lcr, LCR_PEVEN);
799 	}
800 	if (ISSET(t->c_cflag, CSTOPB))
801 		SET(lcr, LCR_STOPB);
802 
803 	sc->sc_lcr = lcr;
804 
805 	if (ospeed == 0) {
806 		CLR(sc->sc_mcr, MCR_DTR);
807 		com_write_reg(sc, com_mcr, sc->sc_mcr);
808 	}
809 
810 	/*
811 	 * Set the FIFO threshold based on the receive speed, if we are
812 	 * changing it.
813 	 */
814 	if (sc->sc_initialize || (tp->t_ispeed != t->c_ispeed)) {
815 		sc->sc_initialize = 0;
816 
817 		if (ospeed != 0) {
818 			/*
819 			 * Make sure the transmit FIFO is empty before
820 			 * proceeding.  If we don't do this, some revisions
821 			 * of the UART will hang.  Interestingly enough,
822 			 * even if we do this while the last character is
823 			 * still being pushed out, they don't hang.  This
824 			 * seems good enough.
825 			 */
826 			while (ISSET(tp->t_state, TS_BUSY)) {
827 				int error;
828 
829 				++sc->sc_halt;
830 				error = ttysleep(tp, &tp->t_outq,
831 				    TTOPRI | PCATCH, "comprm");
832 				--sc->sc_halt;
833 				if (error) {
834 					comstart(tp);
835 					return (error);
836 				}
837 			}
838 
839 			com_write_reg(sc, com_lcr, lcr | LCR_DLAB);
840 			com_write_reg(sc, com_dlbl, ospeed);
841 			com_write_reg(sc, com_dlbh, ospeed >> 8);
842 			com_write_reg(sc, com_lcr, lcr);
843 			SET(sc->sc_mcr, MCR_DTR);
844 			com_write_reg(sc, com_mcr, sc->sc_mcr);
845 		} else
846 			com_write_reg(sc, com_lcr, lcr);
847 
848 		if (ISSET(sc->sc_hwflags, COM_HW_FIFO)) {
849 			if (sc->sc_uarttype == COM_UART_TI16750) {
850 				com_write_reg(sc, com_lcr,
851 				    lcr | LCR_DLAB);
852 				com_write_reg(sc, com_fifo,
853 				    FIFO_ENABLE | FIFO_ENABLE_64BYTE |
854 				    (t->c_ispeed <= 1200 ? FIFO_TRIGGER_1 : FIFO_TRIGGER_8));
855 				com_write_reg(sc, com_lcr, lcr);
856 			} else
857 				com_write_reg(sc, com_fifo,
858 				    FIFO_ENABLE |
859 				    (t->c_ispeed <= 1200 ? FIFO_TRIGGER_1 : FIFO_TRIGGER_8));
860 		}
861 	} else
862 		com_write_reg(sc, com_lcr, lcr);
863 
864 	/* When not using CRTSCTS, RTS follows DTR. */
865 	if (!ISSET(t->c_cflag, CRTSCTS)) {
866 		if (ISSET(sc->sc_mcr, MCR_DTR)) {
867 			if (!ISSET(sc->sc_mcr, MCR_RTS)) {
868 				SET(sc->sc_mcr, MCR_RTS);
869 				com_write_reg(sc, com_mcr, sc->sc_mcr);
870 			}
871 		} else {
872 			if (ISSET(sc->sc_mcr, MCR_RTS)) {
873 				CLR(sc->sc_mcr, MCR_RTS);
874 				com_write_reg(sc, com_mcr, sc->sc_mcr);
875 			}
876 		}
877 		sc->sc_dtr = MCR_DTR | MCR_RTS;
878 	} else
879 		sc->sc_dtr = MCR_DTR;
880 
881 	/* and copy to tty */
882 	tp->t_ispeed = t->c_ispeed;
883 	tp->t_ospeed = t->c_ospeed;
884 	oldcflag = tp->t_cflag;
885 	tp->t_cflag = t->c_cflag;
886 
887 	/*
888 	 * If DCD is off and MDMBUF is changed, ask the tty layer if we should
889 	 * stop the device.
890 	 */
891 	if (!ISSET(sc->sc_msr, MSR_DCD) &&
892 	    !ISSET(sc->sc_swflags, COM_SW_SOFTCAR) &&
893 	    ISSET(oldcflag, MDMBUF) != ISSET(tp->t_cflag, MDMBUF) &&
894 	    (*linesw[tp->t_line].l_modem)(tp, 0) == 0) {
895 		CLR(sc->sc_mcr, sc->sc_dtr);
896 		com_write_reg(sc, com_mcr, sc->sc_mcr);
897 	}
898 
899 	/* Just to be sure... */
900 	comstart(tp);
901 	return 0;
902 }
903 
904 void
comstart(struct tty * tp)905 comstart(struct tty *tp)
906 {
907 	struct com_softc *sc = com_cd.cd_devs[DEVUNIT(tp->t_dev)];
908 	int s;
909 
910 	s = spltty();
911 	if (ISSET(tp->t_state, TS_BUSY))
912 		goto out;
913 	if (ISSET(tp->t_state, TS_TIMEOUT | TS_TTSTOP) || sc->sc_halt > 0)
914 		goto stopped;
915 	if (ISSET(tp->t_cflag, CRTSCTS) && !ISSET(sc->sc_msr, MSR_CTS))
916 		goto stopped;
917 	ttwakeupwr(tp);
918 	if (tp->t_outq.c_cc == 0)
919 		goto stopped;
920 	SET(tp->t_state, TS_BUSY);
921 
922 	/* Enable transmit completion interrupts. */
923 	if (!ISSET(sc->sc_ier, IER_ETXRDY)) {
924 		SET(sc->sc_ier, IER_ETXRDY);
925 		com_write_reg(sc, com_ier, sc->sc_ier);
926 	}
927 
928 	if (ISSET(sc->sc_hwflags, COM_HW_FIFO)) {
929 		u_char buffer[256];	/* largest fifo */
930 		int i, n;
931 
932 		n = q_to_b(&tp->t_outq, buffer,
933 		    min(sc->sc_fifolen, sizeof buffer));
934 		for (i = 0; i < n; i++) {
935 			com_write_reg(sc, com_data, buffer[i]);
936 		}
937 		bzero(buffer, n);
938 	} else if (tp->t_outq.c_cc != 0)
939 		com_write_reg(sc, com_data, getc(&tp->t_outq));
940 out:
941 	splx(s);
942 	return;
943 stopped:
944 	if (ISSET(sc->sc_ier, IER_ETXRDY)) {
945 		CLR(sc->sc_ier, IER_ETXRDY);
946 		com_write_reg(sc, com_ier, sc->sc_ier);
947 	}
948 	splx(s);
949 }
950 
951 /*
952  * Stop output on a line.
953  */
954 int
comstop(struct tty * tp,int flag)955 comstop(struct tty *tp, int flag)
956 {
957 	int s;
958 
959 	s = spltty();
960 	if (ISSET(tp->t_state, TS_BUSY))
961 		if (!ISSET(tp->t_state, TS_TTSTOP))
962 			SET(tp->t_state, TS_FLUSH);
963 	splx(s);
964 	return 0;
965 }
966 
967 void
comdiag(void * arg)968 comdiag(void *arg)
969 {
970 	struct com_softc *sc = arg;
971 	int overflows, floods;
972 	int s;
973 
974 	s = spltty();
975 	sc->sc_errors = 0;
976 	overflows = sc->sc_overflows;
977 	sc->sc_overflows = 0;
978 	floods = sc->sc_floods;
979 	sc->sc_floods = 0;
980 	splx(s);
981 	log(LOG_WARNING, "%s: %d silo overflow%s, %d ibuf overflow%s\n",
982 	    sc->sc_dev.dv_xname,
983 	    overflows, overflows == 1 ? "" : "s",
984 	    floods, floods == 1 ? "" : "s");
985 }
986 
987 void
comsoft(void * arg)988 comsoft(void *arg)
989 {
990 	struct com_softc *sc = (struct com_softc *)arg;
991 	struct tty *tp;
992 	u_char *ibufp;
993 	u_char *ibufend;
994 	int c;
995 	int s;
996 	static int lsrmap[8] = {
997 		0,      TTY_PE,
998 		TTY_FE, TTY_PE|TTY_FE,
999 		TTY_FE, TTY_PE|TTY_FE,
1000 		TTY_FE, TTY_PE|TTY_FE
1001 	};
1002 
1003 	if (sc == NULL || sc->sc_ibufp == sc->sc_ibuf)
1004 		return;
1005 
1006 	tp = sc->sc_tty;
1007 
1008 	s = spltty();
1009 
1010 	ibufp = sc->sc_ibuf;
1011 	ibufend = sc->sc_ibufp;
1012 
1013 	if (ibufp == ibufend) {
1014 		splx(s);
1015 		return;
1016 	}
1017 
1018 	sc->sc_ibufp = sc->sc_ibuf = (ibufp == sc->sc_ibufs[0]) ?
1019 				     sc->sc_ibufs[1] : sc->sc_ibufs[0];
1020 	sc->sc_ibufhigh = sc->sc_ibuf + COM_IHIGHWATER;
1021 	sc->sc_ibufend = sc->sc_ibuf + COM_IBUFSIZE;
1022 
1023 	if (tp == NULL || !ISSET(tp->t_state, TS_ISOPEN)) {
1024 		splx(s);
1025 		return;
1026 	}
1027 
1028 	if (ISSET(tp->t_cflag, CRTSCTS) &&
1029 	    !ISSET(sc->sc_mcr, MCR_RTS)) {
1030 		/* XXX */
1031 		SET(sc->sc_mcr, MCR_RTS);
1032 		com_write_reg(sc, com_mcr, sc->sc_mcr);
1033 	}
1034 
1035 	splx(s);
1036 
1037 	while (ibufp < ibufend) {
1038 		c = *ibufp++;
1039 		if (ISSET(*ibufp, LSR_OE)) {
1040 			sc->sc_overflows++;
1041 			if (sc->sc_errors++ == 0)
1042 				timeout_add_sec(&sc->sc_diag_tmo, 60);
1043 		}
1044 		/* This is ugly, but fast. */
1045 		c |= lsrmap[(*ibufp++ & (LSR_BI|LSR_FE|LSR_PE)) >> 2];
1046 		(*linesw[tp->t_line].l_rint)(c, tp);
1047 	}
1048 }
1049 
1050 int
comintr(void * arg)1051 comintr(void *arg)
1052 {
1053 	struct com_softc *sc = arg;
1054 	struct tty *tp;
1055 	u_char lsr, data, msr, delta;
1056 
1057 	if (!sc->sc_tty)
1058 		return (0);		/* Can't do squat. */
1059 
1060 	if (ISSET(com_read_reg(sc, com_iir), IIR_NOPEND))
1061 		return (0);
1062 
1063 	tp = sc->sc_tty;
1064 
1065 	for (;;) {
1066 		lsr = com_read_reg(sc, com_lsr);
1067 
1068 		if (ISSET(lsr, LSR_RXRDY)) {
1069 			u_char *p = sc->sc_ibufp;
1070 
1071 			softintr_schedule(sc->sc_si);
1072 			do {
1073 				data = com_read_reg(sc, com_data);
1074 				if (ISSET(lsr, LSR_BI)) {
1075 #if defined(COM_CONSOLE) && defined(DDB)
1076 					if (ISSET(sc->sc_hwflags,
1077 					    COM_HW_CONSOLE)) {
1078 						if (db_console)
1079 							db_enter();
1080 						goto next;
1081 					}
1082 #endif
1083 					data = 0;
1084 				}
1085 				if (p >= sc->sc_ibufend) {
1086 					sc->sc_floods++;
1087 					if (sc->sc_errors++ == 0)
1088 						timeout_add_sec(&sc->sc_diag_tmo, 60);
1089 				} else {
1090 					*p++ = data;
1091 					*p++ = lsr;
1092 					if (p == sc->sc_ibufhigh &&
1093 					    ISSET(tp->t_cflag, CRTSCTS)) {
1094 						/* XXX */
1095 						CLR(sc->sc_mcr, MCR_RTS);
1096 						com_write_reg(sc, com_mcr,
1097 						    sc->sc_mcr);
1098 					}
1099 				}
1100 #if defined(COM_CONSOLE) && defined(DDB)
1101 			next:
1102 #endif
1103 				lsr = com_read_reg(sc, com_lsr);
1104 			} while (ISSET(lsr, LSR_RXRDY));
1105 
1106 			sc->sc_ibufp = p;
1107 		}
1108 		msr = com_read_reg(sc, com_msr);
1109 
1110 		if (msr != sc->sc_msr) {
1111 			delta = msr ^ sc->sc_msr;
1112 
1113 			ttytstamp(tp, sc->sc_msr & MSR_CTS, msr & MSR_CTS,
1114 			    sc->sc_msr & MSR_DCD, msr & MSR_DCD);
1115 
1116 			sc->sc_msr = msr;
1117 			if (ISSET(delta, MSR_DCD)) {
1118 				if (!ISSET(sc->sc_swflags, COM_SW_SOFTCAR) &&
1119 				    (*linesw[tp->t_line].l_modem)(tp, ISSET(msr, MSR_DCD)) == 0) {
1120 					CLR(sc->sc_mcr, sc->sc_dtr);
1121 					com_write_reg(sc, com_mcr, sc->sc_mcr);
1122 				}
1123 			}
1124 			if (ISSET(delta & msr, MSR_CTS) &&
1125 			    ISSET(tp->t_cflag, CRTSCTS)) {
1126 				/* the line is up and we want to do rts/cts flow control */
1127 				(*linesw[tp->t_line].l_start)(tp);
1128 			}
1129 		}
1130 
1131 		if (ISSET(lsr, LSR_TXRDY) && ISSET(tp->t_state, TS_BUSY)) {
1132 			CLR(tp->t_state, TS_BUSY | TS_FLUSH);
1133 			if (sc->sc_halt > 0)
1134 				wakeup(&tp->t_outq);
1135 			(*linesw[tp->t_line].l_start)(tp);
1136 		}
1137 
1138 		if (ISSET(com_read_reg(sc, com_iir), IIR_NOPEND))
1139 			return (1);
1140 	}
1141 }
1142 
1143 void
cominit(bus_space_tag_t iot,bus_space_handle_t ioh,int rate,int frequency)1144 cominit(bus_space_tag_t iot, bus_space_handle_t ioh, int rate, int frequency)
1145 {
1146 	int s = splhigh();
1147 	u_char stat;
1148 
1149 	bus_space_write_1(iot, ioh, com_lcr, LCR_DLAB);
1150 	rate = comspeed(frequency, rate); /* XXX not comdefaultrate? */
1151 	bus_space_write_1(iot, ioh, com_dlbl, rate);
1152 	bus_space_write_1(iot, ioh, com_dlbh, rate >> 8);
1153 	bus_space_write_1(iot, ioh, com_lcr, LCR_8BITS);
1154 	bus_space_write_1(iot, ioh, com_mcr, MCR_DTR | MCR_RTS);
1155 	bus_space_write_1(iot, ioh, com_ier, 0);  /* Make sure they are off */
1156 	bus_space_write_1(iot, ioh, com_fifo,
1157 	    FIFO_ENABLE | FIFO_RCV_RST | FIFO_XMT_RST | FIFO_TRIGGER_1);
1158 	stat = bus_space_read_1(iot, ioh, com_iir);
1159 	splx(s);
1160 }
1161 
1162 #ifdef COM_CONSOLE
1163 void
comcnprobe(struct consdev * cp)1164 comcnprobe(struct consdev *cp)
1165 {
1166 	bus_space_handle_t ioh;
1167 	int found = 1;
1168 
1169 	if (comconsaddr == 0)
1170 		return;
1171 
1172 	if (bus_space_map(comconsiot, comconsaddr, COM_NPORTS, 0, &ioh))
1173 		return;
1174 	/* XXX Some com@acpi devices will fail the comprobe1() check */
1175 	if (comcons_reg_width != 4)
1176 		found = comprobe1(comconsiot, ioh);
1177 	bus_space_unmap(comconsiot, ioh, COM_NPORTS);
1178 	if (!found)
1179 		return;
1180 
1181 	/* Locate the major number. */
1182 	for (commajor = 0; commajor < nchrdev; commajor++)
1183 		if (cdevsw[commajor].d_open == comopen)
1184 			break;
1185 
1186 	/* Initialize required fields. */
1187 	cp->cn_dev = makedev(commajor, comconsunit);
1188 	cp->cn_pri = CN_HIGHPRI;
1189 }
1190 
1191 void
comcninit(struct consdev * cp)1192 comcninit(struct consdev *cp)
1193 {
1194 	if (bus_space_map(comconsiot, comconsaddr, COM_NPORTS, 0, &comconsioh))
1195 		panic("comcninit: mapping failed");
1196 
1197 	if (comconsfreq == 0)
1198 		comconsfreq = COM_FREQ;
1199 
1200 	cominit(comconsiot, comconsioh, comconsrate, comconsfreq);
1201 }
1202 
1203 int
comcnattach(bus_space_tag_t iot,bus_addr_t iobase,int rate,int frequency,tcflag_t cflag)1204 comcnattach(bus_space_tag_t iot, bus_addr_t iobase, int rate,
1205     int frequency, tcflag_t cflag)
1206 {
1207 	static struct consdev comcons = {
1208 		NULL, NULL, comcngetc, comcnputc, comcnpollc, NULL,
1209 		NODEV, CN_LOWPRI
1210 	};
1211 
1212 #ifndef __sparc64__
1213 	if (bus_space_map(iot, iobase, COM_NPORTS, 0, &comconsioh))
1214 		return ENOMEM;
1215 #endif
1216 
1217 	cominit(iot, comconsioh, rate, frequency);
1218 
1219 	cn_tab = &comcons;
1220 
1221 	comconsiot = iot;
1222 	comconsaddr = iobase;
1223 	comconscflag = cflag;
1224 	comconsfreq = frequency;
1225 	comconsrate = rate;
1226 
1227 	return (0);
1228 }
1229 
1230 int
comcngetc(dev_t dev)1231 comcngetc(dev_t dev)
1232 {
1233 	int s = splhigh();
1234 	u_char stat, c;
1235 
1236 	/* Block until a character becomes available. */
1237 	while (!ISSET(stat = comcn_read_reg(com_lsr), LSR_RXRDY))
1238 		continue;
1239 
1240 	c = comcn_read_reg(com_data);
1241 
1242 	/* Clear any interrupts generated by this transmission. */
1243 	stat = comcn_read_reg(com_iir);
1244 	splx(s);
1245 	return (c);
1246 }
1247 
1248 /*
1249  * Console kernel output character routine.
1250  */
1251 void
comcnputc(dev_t dev,int c)1252 comcnputc(dev_t dev, int c)
1253 {
1254 	int s = spltty();
1255 	int timo;
1256 
1257 	/* Wait for any pending transmission to finish. */
1258 	timo = 2000;
1259 	while (!ISSET(comcn_read_reg(com_lsr), LSR_TXRDY) && --timo)
1260 		delay(1);
1261 
1262 	comcn_write_reg(com_data, (u_int8_t)(c & 0xff));
1263 	bus_space_barrier(comconsiot, comconsioh, 0,
1264 	    COM_NPORTS << comcons_reg_shift,
1265 	    (BUS_SPACE_BARRIER_READ|BUS_SPACE_BARRIER_WRITE));
1266 
1267 	/* Wait for this transmission to complete. */
1268 	timo = 2000;
1269 	while (!ISSET(comcn_read_reg(com_lsr), LSR_TXRDY) && --timo)
1270 		delay(1);
1271 
1272 	splx(s);
1273 }
1274 
1275 void
comcnpollc(dev_t dev,int on)1276 comcnpollc(dev_t dev, int on)
1277 {
1278 }
1279 #endif	/* COM_CONSOLE */
1280 
1281 void	com_enable_debugport(struct com_softc *);
1282 void	com_fifo_probe(struct com_softc *);
1283 
1284 #ifdef COM_CONSOLE
1285 void
com_enable_debugport(struct com_softc * sc)1286 com_enable_debugport(struct com_softc *sc)
1287 {
1288 	int s;
1289 
1290 	/* Turn on line break interrupt, set carrier. */
1291 	s = splhigh();
1292 	SET(sc->sc_mcr, MCR_DTR | MCR_RTS | MCR_IENABLE);
1293 	com_write_reg(sc, com_mcr, sc->sc_mcr);
1294 
1295 	splx(s);
1296 }
1297 #endif	/* COM_CONSOLE */
1298 
1299 void
com_attach_subr(struct com_softc * sc)1300 com_attach_subr(struct com_softc *sc)
1301 {
1302 	int probe = 0;
1303 	u_int8_t lcr, fifo;
1304 	u_int32_t cpr;
1305 
1306 	sc->sc_ier = 0;
1307 	/* disable interrupts */
1308 	com_write_reg(sc, com_ier, sc->sc_ier);
1309 
1310 #ifdef COM_CONSOLE
1311 	if (sc->sc_iot == comconsiot && sc->sc_iobase == comconsaddr) {
1312 		comconsattached = 1;
1313 		delay(10000);			/* wait for output to finish */
1314 		SET(sc->sc_hwflags, COM_HW_CONSOLE);
1315 		SET(sc->sc_swflags, COM_SW_SOFTCAR);
1316 	}
1317 #endif
1318 
1319 	/*
1320 	 * Probe for all known forms of UART.
1321 	 */
1322 	lcr = com_read_reg(sc, com_lcr);
1323 	com_write_reg(sc, com_lcr, LCR_EFR);
1324 	com_write_reg(sc, com_efr, 0);
1325 	com_write_reg(sc, com_lcr, 0);
1326 
1327 	com_write_reg(sc, com_fifo, FIFO_ENABLE);
1328 	delay(100);
1329 
1330 	/*
1331 	 * Skip specific probes if attachment code knows it already.
1332 	 */
1333 	if (sc->sc_uarttype == COM_UART_UNKNOWN) {
1334 		switch (com_read_reg(sc, com_iir) >> 6) {
1335 		case 0:
1336 			sc->sc_uarttype = COM_UART_16450;
1337 			break;
1338 		case 2:
1339 			sc->sc_uarttype = COM_UART_16550;
1340 			break;
1341 		case 3:
1342 			sc->sc_uarttype = COM_UART_16550A;
1343 			break;
1344 		default:
1345 			sc->sc_uarttype = COM_UART_UNKNOWN;
1346 			break;
1347 		}
1348 		probe = 1;
1349 	}
1350 
1351 	/* Probe for ST16650s */
1352 	if (probe && sc->sc_uarttype == COM_UART_16550A) {
1353 		com_write_reg(sc, com_lcr, lcr | LCR_DLAB);
1354 		if (com_read_reg(sc, com_efr) == 0) {
1355 			com_write_reg(sc, com_efr, EFR_CTS);
1356 			if (com_read_reg(sc, com_efr) != 0)
1357 				sc->sc_uarttype = COM_UART_ST16650;
1358 			com_write_reg(sc, com_efr, 0);
1359 		} else {
1360 			com_write_reg(sc, com_lcr, LCR_EFR);
1361 			if (com_read_reg(sc, com_efr) == 0)
1362 				sc->sc_uarttype = COM_UART_ST16650V2;
1363 		}
1364 	}
1365 
1366 #if 0	/* until com works with large FIFOs */
1367 	/* Probe for XR16850s */
1368 	if (probe && sc->sc_uarttype == COM_UART_ST16650V2) {
1369 		u_int8_t dlbl, dlbh;
1370 
1371 		/* Enable latch access and get the current values. */
1372 		com_write_reg(sc, com_lcr, lcr | LCR_DLAB);
1373 		dlbl = com_read_reg(sc, com_dlbl);
1374 		dlbh = com_read_reg(sc, com_dlbh);
1375 
1376 		/* Zero out the latch divisors */
1377 		com_write_reg(sc, com_dlbl, 0);
1378 		com_write_reg(sc, com_dlbh, 0);
1379 
1380 		if (com_read_reg(sc, com_dlbh) == 0x10) {
1381 			sc->sc_uarttype = COM_UART_XR16850;
1382 			sc->sc_uartrev = com_read_reg(sc, com_dlbl);
1383 		}
1384 
1385 		/* Reset to original. */
1386 		com_write_reg(sc, com_dlbl, dlbl);
1387 		com_write_reg(sc, com_dlbh, dlbh);
1388 	}
1389 #endif
1390 
1391 	/* Probe for TI16750s */
1392 	if (probe && sc->sc_uarttype == COM_UART_16550A) {
1393 		com_write_reg(sc, com_lcr, lcr | LCR_DLAB);
1394 		com_write_reg(sc, com_fifo,
1395 		    FIFO_ENABLE | FIFO_ENABLE_64BYTE);
1396 		if ((com_read_reg(sc, com_iir) >> 5) == 7) {
1397 #if 0
1398 			com_write_reg(sc, com_lcr, 0);
1399 			if ((com_read_reg(sc, com_iir) >> 5) == 6)
1400 #endif
1401 				sc->sc_uarttype = COM_UART_TI16750;
1402 		}
1403 		com_write_reg(sc, com_fifo, FIFO_ENABLE);
1404 	}
1405 
1406 	/* Reset the LCR (latch access is probably enabled). */
1407 	com_write_reg(sc, com_lcr, lcr);
1408 
1409 	/* Probe for 8250 */
1410 	if (probe && sc->sc_uarttype == COM_UART_16450) {
1411 		u_int8_t scr0, scr1, scr2;
1412 
1413 		scr0 = com_read_reg(sc, com_scratch);
1414 		com_write_reg(sc, com_scratch, 0xa5);
1415 		scr1 = com_read_reg(sc, com_scratch);
1416 		com_write_reg(sc, com_scratch, 0x5a);
1417 		scr2 = com_read_reg(sc, com_scratch);
1418 		com_write_reg(sc, com_scratch, scr0);
1419 
1420 		if ((scr1 != 0xa5) || (scr2 != 0x5a))
1421 			sc->sc_uarttype = COM_UART_8250;
1422 	}
1423 
1424 	/*
1425 	 * Print UART type and initialize ourself.
1426 	 */
1427 	switch (sc->sc_uarttype) {
1428 	case COM_UART_UNKNOWN:
1429 		printf(": unknown uart\n");
1430 		break;
1431 	case COM_UART_8250:
1432 		printf(": ns8250, no fifo\n");
1433 		break;
1434 	case COM_UART_16450:
1435 		printf(": ns16450, no fifo\n");
1436 		break;
1437 	case COM_UART_16550:
1438 		printf(": ns16550, no working fifo\n");
1439 		break;
1440 	case COM_UART_16550A:
1441 		if (sc->sc_fifolen == 0)
1442 			sc->sc_fifolen = 16;
1443 		printf(": ns16550a, %d byte fifo\n", sc->sc_fifolen);
1444 		SET(sc->sc_hwflags, COM_HW_FIFO);
1445 		break;
1446 	case COM_UART_ST16650:
1447 		printf(": st16650, no working fifo\n");
1448 		break;
1449 	case COM_UART_ST16650V2:
1450 		if (sc->sc_fifolen == 0)
1451 			sc->sc_fifolen = 32;
1452 		printf(": st16650, %d byte fifo\n", sc->sc_fifolen);
1453 		SET(sc->sc_hwflags, COM_HW_FIFO);
1454 		break;
1455 	case COM_UART_ST16C654:
1456 		printf(": st16c654, 64 byte fifo\n");
1457 		SET(sc->sc_hwflags, COM_HW_FIFO);
1458 		sc->sc_fifolen = 64;
1459 		break;
1460 	case COM_UART_TI16750:
1461 		printf(": ti16750, 64 byte fifo\n");
1462 		SET(sc->sc_hwflags, COM_HW_FIFO);
1463 		sc->sc_fifolen = 64;
1464 		break;
1465 #if 0
1466 	case COM_UART_XR16850:
1467 		printf(": xr16850 (rev %d), 128 byte fifo\n", sc->sc_uartrev);
1468 		SET(sc->sc_hwflags, COM_HW_FIFO);
1469 		sc->sc_fifolen = 128;
1470 		break;
1471 #ifdef COM_UART_OX16C950
1472 	case COM_UART_OX16C950:
1473 		printf(": ox16c950 (rev %d), 128 byte fifo\n", sc->sc_uartrev);
1474 		SET(sc->sc_hwflags, COM_HW_FIFO);
1475 		sc->sc_fifolen = 128;
1476 		break;
1477 #endif
1478 #endif
1479 	case COM_UART_XR17V35X:
1480 		printf(": xr17v35x, 256 byte fifo\n");
1481 		SET(sc->sc_hwflags, COM_HW_FIFO);
1482 		sc->sc_fifolen = 256;
1483 		break;
1484 	case COM_UART_DW_APB:
1485 		printf(": dw16550");
1486 		SET(sc->sc_hwflags, COM_HW_FIFO);
1487 		cpr = bus_space_read_4(sc->sc_iot, sc->sc_ioh, com_cpr << 2);
1488 		sc->sc_fifolen = CPR_FIFO_MODE(cpr) * 16;
1489 		if (sc->sc_fifolen) {
1490 			printf(", %d byte fifo\n", sc->sc_fifolen);
1491 		} else {
1492 			printf("\n");
1493 			/*
1494 			 * The DW-APB configuration on the Allwinner H6 SoC
1495 			 * does not provide the CPR register and will be
1496 			 * detected as having no FIFO.  But it does have a
1497 			 * 256-byte FIFO and with the FIFO disabled the
1498 			 * LSR_RXRDY bit remains set even if the input
1499 			 * buffer is empty.  As a workaround, treat as a
1500 			 * 1-byte FIFO.
1501 			 */
1502 			sc->sc_fifolen = 1;
1503 		}
1504 		break;
1505 	default:
1506 		panic("comattach: bad fifo type");
1507 	}
1508 
1509 #ifdef COM_CONSOLE
1510 	if (!ISSET(sc->sc_hwflags, COM_HW_CONSOLE))
1511 #endif
1512 		if (sc->sc_fifolen < 256)
1513 			com_fifo_probe(sc);
1514 
1515 	if (sc->sc_fifolen == 0) {
1516 		CLR(sc->sc_hwflags, COM_HW_FIFO);
1517 		sc->sc_fifolen = 1;
1518 	}
1519 
1520 	/* clear and disable fifo */
1521 	/* DW-APB UART cannot turn off FIFO here (ddb will not work) */
1522 	fifo = (sc->sc_uarttype == COM_UART_DW_APB) ?
1523 		(FIFO_ENABLE | FIFO_TRIGGER_1) : 0;
1524 	com_write_reg(sc, com_fifo, fifo | FIFO_RCV_RST | FIFO_XMT_RST);
1525 	if (ISSET(com_read_reg(sc, com_lsr), LSR_RXRDY))
1526 		(void)com_read_reg(sc, com_data);
1527 	com_write_reg(sc, com_fifo, fifo);
1528 
1529 	sc->sc_mcr = 0;
1530 	com_write_reg(sc, com_mcr, sc->sc_mcr);
1531 
1532 #ifdef COM_CONSOLE
1533 	if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
1534 		int maj;
1535 
1536 		/* locate the major number */
1537 		for (maj = 0; maj < nchrdev; maj++)
1538 			if (cdevsw[maj].d_open == comopen)
1539 				break;
1540 
1541 		KASSERT(maj < nchrdev);
1542 		cn_tab->cn_dev = makedev(maj, sc->sc_dev.dv_unit);
1543 
1544 		printf("%s: console\n", sc->sc_dev.dv_xname);
1545 	}
1546 #endif
1547 
1548 	timeout_set(&sc->sc_diag_tmo, comdiag, sc);
1549 	timeout_set(&sc->sc_dtr_tmo, com_raisedtr, sc);
1550 	sc->sc_si = softintr_establish(IPL_TTY, comsoft, sc);
1551 	if (sc->sc_si == NULL)
1552 		panic("%s: can't establish soft interrupt",
1553 		    sc->sc_dev.dv_xname);
1554 
1555 	/*
1556 	 * If there are no enable/disable functions, assume the device
1557 	 * is always enabled.
1558 	 */
1559 	if (!sc->enable)
1560 		sc->enabled = 1;
1561 
1562 #ifdef COM_CONSOLE
1563 	if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE))
1564 		com_enable_debugport(sc);
1565 #endif
1566 }
1567 
1568 void
com_fifo_probe(struct com_softc * sc)1569 com_fifo_probe(struct com_softc *sc)
1570 {
1571 	u_int8_t fifo, ier;
1572 	int timo, len;
1573 
1574 	if (!ISSET(sc->sc_hwflags, COM_HW_FIFO))
1575 		return;
1576 
1577 	ier = 0;
1578 	com_write_reg(sc, com_ier, ier);
1579 	com_write_reg(sc, com_lcr, LCR_DLAB);
1580 	com_write_reg(sc, com_dlbl, 3);
1581 	com_write_reg(sc, com_dlbh, 0);
1582 	com_write_reg(sc, com_lcr, LCR_PNONE | LCR_8BITS);
1583 	com_write_reg(sc, com_mcr, MCR_LOOPBACK);
1584 
1585 	fifo = FIFO_ENABLE | FIFO_RCV_RST | FIFO_XMT_RST;
1586 	if (sc->sc_uarttype == COM_UART_TI16750)
1587 		fifo |= FIFO_ENABLE_64BYTE;
1588 
1589 	com_write_reg(sc, com_fifo, fifo);
1590 
1591 	for (len = 0; len < 256; len++) {
1592 		com_write_reg(sc, com_data, (len + 1));
1593 		timo = 2000;
1594 		while (!ISSET(com_read_reg(sc, com_lsr),
1595 		    LSR_TXRDY) && --timo)
1596 			delay(1);
1597 		if (!timo)
1598 			break;
1599 	}
1600 
1601 	delay(100);
1602 
1603 	for (len = 0; len < 256; len++) {
1604 		timo = 2000;
1605 		while (!ISSET(com_read_reg(sc, com_lsr),
1606 		    LSR_RXRDY) && --timo)
1607 			delay(1);
1608 		if (!timo || com_read_reg(sc, com_data) != (len + 1))
1609 			break;
1610 	}
1611 
1612 	/* For safety, always use the smaller value. */
1613 	if (sc->sc_fifolen > len) {
1614 		printf("%s: probed fifo depth: %d bytes\n",
1615 		    sc->sc_dev.dv_xname, len);
1616 		sc->sc_fifolen = len;
1617 	}
1618 }
1619 
1620 uint8_t
com_read_reg(struct com_softc * sc,bus_size_t reg)1621 com_read_reg(struct com_softc *sc, bus_size_t reg)
1622 {
1623 	reg <<= sc->sc_reg_shift;
1624 
1625 	if (sc->sc_reg_width == 4)
1626 		return bus_space_read_4(sc->sc_iot, sc->sc_ioh, reg);
1627 	else
1628 		return bus_space_read_1(sc->sc_iot, sc->sc_ioh, reg);
1629 }
1630 
1631 void
com_write_reg(struct com_softc * sc,bus_size_t reg,uint8_t value)1632 com_write_reg(struct com_softc *sc, bus_size_t reg, uint8_t value)
1633 {
1634 	reg <<= sc->sc_reg_shift;
1635 
1636 	if (sc->sc_reg_width == 4)
1637 		bus_space_write_4(sc->sc_iot, sc->sc_ioh, reg, value);
1638 	else
1639 		bus_space_write_1(sc->sc_iot, sc->sc_ioh, reg, value);
1640 }
1641 
1642 #ifdef COM_CONSOLE
1643 
1644 u_char comcons_reg_width;
1645 u_char comcons_reg_shift;
1646 
1647 uint8_t
comcn_read_reg(bus_size_t reg)1648 comcn_read_reg(bus_size_t reg)
1649 {
1650 	reg <<= comcons_reg_shift;
1651 
1652 	if (comcons_reg_width == 4)
1653 		return bus_space_read_4(comconsiot, comconsioh, reg);
1654 	else
1655 		return bus_space_read_1(comconsiot, comconsioh, reg);
1656 }
1657 
1658 void
comcn_write_reg(bus_size_t reg,uint8_t value)1659 comcn_write_reg(bus_size_t reg, uint8_t value)
1660 {
1661 	reg <<= comcons_reg_shift;
1662 
1663 	if (comcons_reg_width == 4)
1664 		bus_space_write_4(comconsiot, comconsioh, reg, value);
1665 	else
1666 		bus_space_write_1(comconsiot, comconsioh, reg, value);
1667 }
1668 
1669 #endif
1670