xref: /netbsd-src/sys/dev/ic/com.c (revision cd22f25e6f6d1cc1f197fe8c5468a80f51d1c4e1)
1 /*	com.c,v 1.262.2.3 2008/01/09 01:52:50 matt Exp	*/
2 
3 /*-
4  * Copyright (c) 1998, 1999, 2004, 2008 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Charles M. Hannum.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 /*
33  * Copyright (c) 1991 The Regents of the University of California.
34  * All rights reserved.
35  *
36  * Redistribution and use in source and binary forms, with or without
37  * modification, are permitted provided that the following conditions
38  * are met:
39  * 1. Redistributions of source code must retain the above copyright
40  *    notice, this list of conditions and the following disclaimer.
41  * 2. Redistributions in binary form must reproduce the above copyright
42  *    notice, this list of conditions and the following disclaimer in the
43  *    documentation and/or other materials provided with the distribution.
44  * 3. Neither the name of the University nor the names of its contributors
45  *    may be used to endorse or promote products derived from this software
46  *    without specific prior written permission.
47  *
48  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
49  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
50  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
51  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
52  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
53  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
54  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
55  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
56  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
57  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
58  * SUCH DAMAGE.
59  *
60  *	@(#)com.c	7.5 (Berkeley) 5/16/91
61  */
62 
63 /*
64  * COM driver, uses National Semiconductor NS16450/NS16550AF UART
65  * Supports automatic hardware flow control on StarTech ST16C650A UART
66  */
67 
68 #include <sys/cdefs.h>
69 __KERNEL_RCSID(0, "com.c,v 1.262.2.3 2008/01/09 01:52:50 matt Exp");
70 
71 #include "opt_com.h"
72 #include "opt_ddb.h"
73 #include "opt_kgdb.h"
74 #include "opt_lockdebug.h"
75 #include "opt_multiprocessor.h"
76 #include "opt_ntp.h"
77 
78 #include "rnd.h"
79 #if NRND > 0 && defined(RND_COM)
80 #include <sys/rnd.h>
81 #endif
82 
83 /* The COM16650 option was renamed to COM_16650. */
84 #ifdef COM16650
85 #error Obsolete COM16650 option; use COM_16650 instead.
86 #endif
87 
88 /*
89  * Override cnmagic(9) macro before including <sys/systm.h>.
90  * We need to know if cn_check_magic triggered debugger, so set a flag.
91  * Callers of cn_check_magic must declare int cn_trapped = 0;
92  * XXX: this is *ugly*!
93  */
94 #define cn_trap()				\
95 	do {					\
96 		console_debugger();		\
97 		cn_trapped = 1;			\
98 	} while (/* CONSTCOND */ 0)
99 
100 #include <sys/param.h>
101 #include <sys/systm.h>
102 #include <sys/ioctl.h>
103 #include <sys/select.h>
104 #include <sys/poll.h>
105 #include <sys/tty.h>
106 #include <sys/proc.h>
107 #include <sys/user.h>
108 #include <sys/conf.h>
109 #include <sys/file.h>
110 #include <sys/uio.h>
111 #include <sys/kernel.h>
112 #include <sys/syslog.h>
113 #include <sys/device.h>
114 #include <sys/malloc.h>
115 #include <sys/timepps.h>
116 #include <sys/vnode.h>
117 #include <sys/kauth.h>
118 #include <sys/intr.h>
119 
120 #include <sys/bus.h>
121 
122 #include <dev/ic/comreg.h>
123 #include <dev/ic/comvar.h>
124 #include <dev/ic/ns16550reg.h>
125 #include <dev/ic/st16650reg.h>
126 #ifdef COM_HAYESP
127 #include <dev/ic/hayespreg.h>
128 #endif
129 #define	com_lcr	com_cfcr
130 #include <dev/cons.h>
131 
132 #ifdef	COM_REGMAP
133 #define	CSR_WRITE_1(r, o, v)	\
134 	bus_space_write_1((r)->cr_iot, (r)->cr_ioh, (r)->cr_map[o], v)
135 #define	CSR_READ_1(r, o)	\
136 	bus_space_read_1((r)->cr_iot, (r)->cr_ioh, (r)->cr_map[o])
137 #define	CSR_WRITE_2(r, o, v)	\
138 	bus_space_write_2((r)->cr_iot, (r)->cr_ioh, (r)->cr_map[o], v)
139 #define	CSR_READ_2(r, o)	\
140 	bus_space_read_2((r)->cr_iot, (r)->cr_ioh, (r)->cr_map[o])
141 #define	CSR_WRITE_MULTI(r, o, p, n)	\
142 	bus_space_write_multi_1((r)->cr_iot, (r)->cr_ioh, (r)->cr_map[o], p, n)
143 #else
144 #define	CSR_WRITE_1(r, o, v)	\
145 	bus_space_write_1((r)->cr_iot, (r)->cr_ioh, o, v)
146 #define	CSR_READ_1(r, o)	\
147 	bus_space_read_1((r)->cr_iot, (r)->cr_ioh, o)
148 #define	CSR_WRITE_2(r, o, v)	\
149 	bus_space_write_2((r)->cr_iot, (r)->cr_ioh, o, v)
150 #define	CSR_READ_2(r, o)	\
151 	bus_space_read_2((r)->cr_iot, (r)->cr_ioh, o)
152 #define	CSR_WRITE_MULTI(r, o, p, n)	\
153 	bus_space_write_multi_1((r)->cr_iot, (r)->cr_ioh, o, p, n)
154 #endif
155 
156 
157 static void com_enable_debugport(struct com_softc *);
158 
159 void	com_config(struct com_softc *);
160 void	com_shutdown(struct com_softc *);
161 int	comspeed(long, long, int);
162 static	u_char	cflag2lcr(tcflag_t);
163 int	comparam(struct tty *, struct termios *);
164 void	comstart(struct tty *);
165 int	comhwiflow(struct tty *, int);
166 
167 void	com_loadchannelregs(struct com_softc *);
168 void	com_hwiflow(struct com_softc *);
169 void	com_break(struct com_softc *, int);
170 void	com_modem(struct com_softc *, int);
171 void	tiocm_to_com(struct com_softc *, u_long, int);
172 int	com_to_tiocm(struct com_softc *);
173 void	com_iflush(struct com_softc *);
174 
175 int	com_common_getc(dev_t, struct com_regs *);
176 void	com_common_putc(dev_t, struct com_regs *, int);
177 
178 int	cominit(struct com_regs *, int, int, int, tcflag_t);
179 
180 int	comcngetc(dev_t);
181 void	comcnputc(dev_t, int);
182 void	comcnpollc(dev_t, int);
183 
184 #define	integrate	static inline
185 void 	comsoft(void *);
186 integrate void com_rxsoft(struct com_softc *, struct tty *);
187 integrate void com_txsoft(struct com_softc *, struct tty *);
188 integrate void com_stsoft(struct com_softc *, struct tty *);
189 integrate void com_schedrx(struct com_softc *);
190 void	comdiag(void *);
191 
192 extern struct cfdriver com_cd;
193 
194 dev_type_open(comopen);
195 dev_type_close(comclose);
196 dev_type_read(comread);
197 dev_type_write(comwrite);
198 dev_type_ioctl(comioctl);
199 dev_type_stop(comstop);
200 dev_type_tty(comtty);
201 dev_type_poll(compoll);
202 
203 const struct cdevsw com_cdevsw = {
204 	comopen, comclose, comread, comwrite, comioctl,
205 	comstop, comtty, compoll, nommap, ttykqfilter, D_TTY
206 };
207 
208 /*
209  * Make this an option variable one can patch.
210  * But be warned:  this must be a power of 2!
211  */
212 u_int com_rbuf_size = COM_RING_SIZE;
213 
214 /* Stop input when 3/4 of the ring is full; restart when only 1/4 is full. */
215 u_int com_rbuf_hiwat = (COM_RING_SIZE * 1) / 4;
216 u_int com_rbuf_lowat = (COM_RING_SIZE * 3) / 4;
217 
218 static struct com_regs comconsregs;
219 static int comconsattached;
220 static int comconsrate;
221 static tcflag_t comconscflag;
222 static struct cnm_state com_cnm_state;
223 
224 #ifdef KGDB
225 #include <sys/kgdb.h>
226 
227 static struct com_regs comkgdbregs;
228 static int com_kgdb_attached;
229 
230 int	com_kgdb_getc(void *);
231 void	com_kgdb_putc(void *, int);
232 #endif /* KGDB */
233 
234 #ifdef COM_REGMAP
235 /* initializer for typical 16550-ish hardware */
236 #define	COM_REG_16550	{ \
237 	com_data, com_data, com_dlbl, com_dlbh, com_ier, com_iir, com_fifo, \
238 	com_efr, com_lcr, com_mcr, com_lsr, com_msr }
239 
240 const bus_size_t com_std_map[16] = COM_REG_16550;
241 #endif /* COM_REGMAP */
242 
243 #define	COMUNIT_MASK	0x7ffff
244 #define	COMDIALOUT_MASK	0x80000
245 
246 #define	COMUNIT(x)	(minor(x) & COMUNIT_MASK)
247 #define	COMDIALOUT(x)	(minor(x) & COMDIALOUT_MASK)
248 
249 #define	COM_ISALIVE(sc)	((sc)->enabled != 0 && \
250 			 device_is_active((sc)->sc_dev))
251 
252 #define	BR	BUS_SPACE_BARRIER_READ
253 #define	BW	BUS_SPACE_BARRIER_WRITE
254 #define COM_BARRIER(r, f) \
255 	bus_space_barrier((r)->cr_iot, (r)->cr_ioh, 0, (r)->cr_nports, (f))
256 
257 /*ARGSUSED*/
258 int
259 comspeed(long speed, long frequency, int type)
260 {
261 #define	divrnd(n, q)	(((n)*2/(q)+1)/2)	/* divide and round off */
262 
263 	int x, err;
264 	int divisor = 16;
265 
266 	if ((type == COM_TYPE_OMAP) && (speed > 230400)) {
267 	    divisor = 13;
268 	}
269 
270 #if 0
271 	if (speed == 0)
272 		return (0);
273 #endif
274 	if (speed <= 0)
275 		return (-1);
276 	x = divrnd(frequency / divisor, speed);
277 	if (x <= 0)
278 		return (-1);
279 	err = divrnd(((quad_t)frequency) * 1000 / divisor, speed * x) - 1000;
280 	if (err < 0)
281 		err = -err;
282 	if (err > COM_TOLERANCE)
283 		return (-1);
284 	return (x);
285 
286 #undef	divrnd
287 }
288 
289 #ifdef COM_DEBUG
290 int	com_debug = 0;
291 
292 void comstatus(struct com_softc *, const char *);
293 void
294 comstatus(struct com_softc *sc, const char *str)
295 {
296 	struct tty *tp = sc->sc_tty;
297 
298 	aprint_normal_dev(sc->sc_dev,
299 	    "%s %cclocal  %cdcd %cts_carr_on %cdtr %ctx_stopped\n",
300 	    str,
301 	    ISSET(tp->t_cflag, CLOCAL) ? '+' : '-',
302 	    ISSET(sc->sc_msr, MSR_DCD) ? '+' : '-',
303 	    ISSET(tp->t_state, TS_CARR_ON) ? '+' : '-',
304 	    ISSET(sc->sc_mcr, MCR_DTR) ? '+' : '-',
305 	    sc->sc_tx_stopped ? '+' : '-');
306 
307 	aprint_normal_dev(sc->sc_dev,
308 	    "%s %ccrtscts %ccts %cts_ttstop  %crts rx_flags=0x%x\n",
309 	    str,
310 	    ISSET(tp->t_cflag, CRTSCTS) ? '+' : '-',
311 	    ISSET(sc->sc_msr, MSR_CTS) ? '+' : '-',
312 	    ISSET(tp->t_state, TS_TTSTOP) ? '+' : '-',
313 	    ISSET(sc->sc_mcr, MCR_RTS) ? '+' : '-',
314 	    sc->sc_rx_flags);
315 }
316 #endif
317 
318 int
319 com_probe_subr(struct com_regs *regs)
320 {
321 
322 	/* force access to id reg */
323 	CSR_WRITE_1(regs, COM_REG_LCR, LCR_8BITS);
324 	CSR_WRITE_1(regs, COM_REG_IIR, 0);
325 	if ((CSR_READ_1(regs, COM_REG_LCR) != LCR_8BITS) ||
326 	    (CSR_READ_1(regs, COM_REG_IIR) & 0x38))
327 		return (0);
328 
329 	return (1);
330 }
331 
332 int
333 comprobe1(bus_space_tag_t iot, bus_space_handle_t ioh)
334 {
335 	struct com_regs	regs;
336 
337 	regs.cr_iot = iot;
338 	regs.cr_ioh = ioh;
339 #ifdef	COM_REGMAP
340 	memcpy(regs.cr_map, com_std_map, sizeof (regs.cr_map));;
341 #endif
342 
343 	return com_probe_subr(&regs);
344 }
345 
346 /*
347  * No locking in this routine; it is only called during attach,
348  * or with the port already locked.
349  */
350 static void
351 com_enable_debugport(struct com_softc *sc)
352 {
353 
354 	/* Turn on line break interrupt, set carrier. */
355 	sc->sc_ier = IER_ERXRDY;
356 	if (sc->sc_type == COM_TYPE_PXA2x0)
357 		sc->sc_ier |= IER_EUART | IER_ERXTOUT;
358 	CSR_WRITE_1(&sc->sc_regs, COM_REG_IER, sc->sc_ier);
359 	SET(sc->sc_mcr, MCR_DTR | MCR_RTS);
360 	CSR_WRITE_1(&sc->sc_regs, COM_REG_MCR, sc->sc_mcr);
361 }
362 
363 void
364 com_attach_subr(struct com_softc *sc)
365 {
366 	struct com_regs *regsp = &sc->sc_regs;
367 	struct tty *tp;
368 #ifdef COM_16650
369 	u_int8_t lcr;
370 #endif
371 	const char *fifo_msg = NULL;
372 
373 	aprint_naive("\n");
374 
375 	callout_init(&sc->sc_diag_callout, 0);
376 	mutex_init(&sc->sc_lock, MUTEX_DEFAULT, IPL_HIGH);
377 
378 	/* Disable interrupts before configuring the device. */
379 	if (sc->sc_type == COM_TYPE_PXA2x0)
380 		sc->sc_ier = IER_EUART;
381 	else
382 		sc->sc_ier = 0;
383 
384 	CSR_WRITE_1(regsp, COM_REG_IER, sc->sc_ier);
385 
386 	if (regsp->cr_iot == comconsregs.cr_iot &&
387 	    regsp->cr_iobase == comconsregs.cr_iobase) {
388 		comconsattached = 1;
389 
390 		/* Make sure the console is always "hardwired". */
391 		delay(10000);			/* wait for output to finish */
392 		SET(sc->sc_hwflags, COM_HW_CONSOLE);
393 		SET(sc->sc_swflags, TIOCFLAG_SOFTCAR);
394 	}
395 
396 	/* Probe for FIFO */
397 	switch (sc->sc_type) {
398 	case COM_TYPE_HAYESP:
399 		goto fifodone;
400 
401 	case COM_TYPE_AU1x00:
402 		sc->sc_fifolen = 16;
403 		fifo_msg = "Au1X00 UART, working fifo";
404 		SET(sc->sc_hwflags, COM_HW_FIFO);
405 		goto fifodelay;
406 
407  	case COM_TYPE_OMAP:
408  		sc->sc_fifolen = 64;
409  		fifo_msg = "OMAP UART, working fifo";
410  		SET(sc->sc_hwflags, COM_HW_FIFO);
411  		goto fifodelay;
412   	}
413 
414 	sc->sc_fifolen = 1;
415 	/* look for a NS 16550AF UART with FIFOs */
416 	CSR_WRITE_1(regsp, COM_REG_FIFO,
417 	    FIFO_ENABLE | FIFO_RCV_RST | FIFO_XMT_RST | FIFO_TRIGGER_14);
418 	delay(100);
419 	if (ISSET(CSR_READ_1(regsp, COM_REG_IIR), IIR_FIFO_MASK)
420 	    == IIR_FIFO_MASK)
421 		if (ISSET(CSR_READ_1(regsp, COM_REG_FIFO), FIFO_TRIGGER_14)
422 		    == FIFO_TRIGGER_14) {
423 			SET(sc->sc_hwflags, COM_HW_FIFO);
424 
425 #ifdef COM_16650
426 			/*
427 			 * IIR changes into the EFR if LCR is set to LCR_EERS
428 			 * on 16650s. We also know IIR != 0 at this point.
429 			 * Write 0 into the EFR, and read it. If the result
430 			 * is 0, we have a 16650.
431 			 *
432 			 * Older 16650s were broken; the test to detect them
433 			 * is taken from the Linux driver. Apparently
434 			 * setting DLAB enable gives access to the EFR on
435 			 * these chips.
436 			 */
437 			lcr = CSR_READ_1(regsp, COM_REG_LCR);
438 			CSR_WRITE_1(regsp, COM_REG_LCR, LCR_EERS);
439 			CSR_WRITE_1(regsp, COM_REG_EFR, 0);
440 			if (CSR_READ_1(regsp, COM_REG_EFR) == 0) {
441 				CSR_WRITE_1(regsp, COM_REG_LCR,
442 				    lcr | LCR_DLAB);
443 				if (CSR_READ_1(regsp, COM_REG_EFR) == 0) {
444 					CLR(sc->sc_hwflags, COM_HW_FIFO);
445 					sc->sc_fifolen = 0;
446 				} else {
447 					SET(sc->sc_hwflags, COM_HW_FLOW);
448 					sc->sc_fifolen = 32;
449 				}
450 			} else
451 #endif
452 				sc->sc_fifolen = 16;
453 
454 #ifdef COM_16650
455 			CSR_WRITE_1(regsp, COM_REG_LCR, lcr);
456 			if (sc->sc_fifolen == 0)
457 				fifo_msg = "st16650, broken fifo";
458 			else if (sc->sc_fifolen == 32)
459 				fifo_msg = "st16650a, working fifo";
460 			else
461 #endif
462 				fifo_msg = "ns16550a, working fifo";
463 		} else
464 			fifo_msg = "ns16550, broken fifo";
465 	else
466 		fifo_msg = "ns8250 or ns16450, no fifo";
467 	CSR_WRITE_1(regsp, COM_REG_FIFO, 0);
468 fifodelay:
469 	/*
470 	 * Some chips will clear down both Tx and Rx FIFOs when zero is
471 	 * written to com_fifo. If this chip is the console, writing zero
472 	 * results in some of the chip/FIFO description being lost, so delay
473 	 * printing it until now.
474 	 */
475 	delay(10);
476 	aprint_normal(": %s\n", fifo_msg);
477 	if (ISSET(sc->sc_hwflags, COM_HW_TXFIFO_DISABLE)) {
478 		sc->sc_fifolen = 1;
479 		aprint_normal_dev(sc->sc_dev, "txfifo disabled\n");
480 	}
481 
482 fifodone:
483 
484 	tp = ttymalloc();
485 	tp->t_oproc = comstart;
486 	tp->t_param = comparam;
487 	tp->t_hwiflow = comhwiflow;
488 
489 	sc->sc_tty = tp;
490 	sc->sc_rbuf = malloc(com_rbuf_size << 1, M_DEVBUF, M_NOWAIT);
491 	sc->sc_rbput = sc->sc_rbget = sc->sc_rbuf;
492 	sc->sc_rbavail = com_rbuf_size;
493 	if (sc->sc_rbuf == NULL) {
494 		aprint_error_dev(sc->sc_dev,
495 		    "unable to allocate ring buffer\n");
496 		return;
497 	}
498 	sc->sc_ebuf = sc->sc_rbuf + (com_rbuf_size << 1);
499 
500 	tty_attach(tp);
501 
502 	if (!ISSET(sc->sc_hwflags, COM_HW_NOIEN))
503 		SET(sc->sc_mcr, MCR_IENABLE);
504 
505 	if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
506 		int maj;
507 
508 		/* locate the major number */
509 		maj = cdevsw_lookup_major(&com_cdevsw);
510 
511 		tp->t_dev = cn_tab->cn_dev = makedev(maj,
512 						     device_unit(sc->sc_dev));
513 
514 		aprint_normal_dev(sc->sc_dev, "console\n");
515 	}
516 
517 #ifdef KGDB
518 	/*
519 	 * Allow kgdb to "take over" this port.  If this is
520 	 * not the console and is the kgdb device, it has
521 	 * exclusive use.  If it's the console _and_ the
522 	 * kgdb device, it doesn't.
523 	 */
524 	if (regsp->cr_iot == comkgdbregs.cr_iot &&
525 	    regsp->cr_iobase == comkgdbregs.cr_iobase) {
526 		if (!ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
527 			com_kgdb_attached = 1;
528 
529 			SET(sc->sc_hwflags, COM_HW_KGDB);
530 		}
531 		aprint_normal_dev(sc->sc_dev, "kgdb\n");
532 	}
533 #endif
534 
535 	sc->sc_si = softint_establish(SOFTINT_SERIAL, comsoft, sc);
536 
537 #if NRND > 0 && defined(RND_COM)
538 	rnd_attach_source(&sc->rnd_source, device_xname(sc->sc_dev),
539 			  RND_TYPE_TTY, 0);
540 #endif
541 
542 	/* if there are no enable/disable functions, assume the device
543 	   is always enabled */
544 	if (!sc->enable)
545 		sc->enabled = 1;
546 
547 	com_config(sc);
548 
549 	SET(sc->sc_hwflags, COM_HW_DEV_OK);
550 }
551 
552 void
553 com_config(struct com_softc *sc)
554 {
555 	struct com_regs *regsp = &sc->sc_regs;
556 
557 	/* Disable interrupts before configuring the device. */
558 	if (sc->sc_type == COM_TYPE_PXA2x0)
559 		sc->sc_ier = IER_EUART;
560 	else
561 		sc->sc_ier = 0;
562 	CSR_WRITE_1(regsp, COM_REG_IER, sc->sc_ier);
563 	(void) CSR_READ_1(regsp, COM_REG_IIR);
564 
565 #ifdef COM_HAYESP
566 	/* Look for a Hayes ESP board. */
567 	if (sc->sc_type == COM_TYPE_HAYESP) {
568 
569 		/* Set 16550 compatibility mode */
570 		bus_space_write_1(regsp->cr_iot, sc->sc_hayespioh, HAYESP_CMD1,
571 				  HAYESP_SETMODE);
572 		bus_space_write_1(regsp->cr_iot, sc->sc_hayespioh, HAYESP_CMD2,
573 				  HAYESP_MODE_FIFO|HAYESP_MODE_RTS|
574 				  HAYESP_MODE_SCALE);
575 
576 		/* Set RTS/CTS flow control */
577 		bus_space_write_1(regsp->cr_iot, sc->sc_hayespioh, HAYESP_CMD1,
578 				  HAYESP_SETFLOWTYPE);
579 		bus_space_write_1(regsp->cr_iot, sc->sc_hayespioh, HAYESP_CMD2,
580 				  HAYESP_FLOW_RTS);
581 		bus_space_write_1(regsp->cr_iot, sc->sc_hayespioh, HAYESP_CMD2,
582 				  HAYESP_FLOW_CTS);
583 
584 		/* Set flow control levels */
585 		bus_space_write_1(regsp->cr_iot, sc->sc_hayespioh, HAYESP_CMD1,
586 				  HAYESP_SETRXFLOW);
587 		bus_space_write_1(regsp->cr_iot, sc->sc_hayespioh, HAYESP_CMD2,
588 				  HAYESP_HIBYTE(HAYESP_RXHIWMARK));
589 		bus_space_write_1(regsp->cr_iot, sc->sc_hayespioh, HAYESP_CMD2,
590 				  HAYESP_LOBYTE(HAYESP_RXHIWMARK));
591 		bus_space_write_1(regsp->cr_iot, sc->sc_hayespioh, HAYESP_CMD2,
592 				  HAYESP_HIBYTE(HAYESP_RXLOWMARK));
593 		bus_space_write_1(regsp->cr_iot, sc->sc_hayespioh, HAYESP_CMD2,
594 				  HAYESP_LOBYTE(HAYESP_RXLOWMARK));
595 	}
596 #endif
597 
598 	if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE|COM_HW_KGDB))
599 		com_enable_debugport(sc);
600 }
601 
602 int
603 com_detach(device_t self, int flags)
604 {
605 	struct com_softc *sc = device_private(self);
606 	int maj, mn;
607 
608         if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE))
609 		return EBUSY;
610 
611 	/* locate the major number */
612 	maj = cdevsw_lookup_major(&com_cdevsw);
613 
614 	/* Nuke the vnodes for any open instances. */
615 	mn = device_unit(self);
616 	vdevgone(maj, mn, mn, VCHR);
617 
618 	mn |= COMDIALOUT_MASK;
619 	vdevgone(maj, mn, mn, VCHR);
620 
621 	if (sc->sc_rbuf == NULL) {
622 		/*
623 		 * Ring buffer allocation failed in the com_attach_subr,
624 		 * only the tty is allocated, and nothing else.
625 		 */
626 		ttyfree(sc->sc_tty);
627 		return 0;
628 	}
629 
630 	/* Free the receive buffer. */
631 	free(sc->sc_rbuf, M_DEVBUF);
632 
633 	/* Detach and free the tty. */
634 	tty_detach(sc->sc_tty);
635 	ttyfree(sc->sc_tty);
636 
637 	/* Unhook the soft interrupt handler. */
638 	softint_disestablish(sc->sc_si);
639 
640 #if NRND > 0 && defined(RND_COM)
641 	/* Unhook the entropy source. */
642 	rnd_detach_source(&sc->rnd_source);
643 #endif
644 	callout_destroy(&sc->sc_diag_callout);
645 
646 	/* Destroy the lock. */
647 	mutex_destroy(&sc->sc_lock);
648 
649 	return (0);
650 }
651 
652 int
653 com_activate(device_t self, enum devact act)
654 {
655 	struct com_softc *sc = device_private(self);
656 	int rv = 0;
657 
658 	switch (act) {
659 	case DVACT_ACTIVATE:
660 		rv = EOPNOTSUPP;
661 		break;
662 
663 	case DVACT_DEACTIVATE:
664 		if (sc->sc_hwflags & (COM_HW_CONSOLE|COM_HW_KGDB)) {
665 			rv = EBUSY;
666 			break;
667 		}
668 
669 		if (sc->disable != NULL && sc->enabled != 0) {
670 			(*sc->disable)(sc);
671 			sc->enabled = 0;
672 		}
673 		break;
674 	}
675 
676 	if (sc->sc_type == COM_TYPE_OMAP) {
677 		/* enable but mode is based on speed */
678 		if (sc->sc_tty->t_termios.c_ospeed > 230400) {
679 			CSR_WRITE_1(&sc->sc_regs, COM_REG_MDR1, MDR1_MODE_UART_13X);
680 		} else {
681 			CSR_WRITE_1(&sc->sc_regs, COM_REG_MDR1, MDR1_MODE_UART_16X);
682 		}
683 	}
684 	mutex_spin_exit(&sc->sc_lock);
685 	return (rv);
686 }
687 
688 void
689 com_shutdown(struct com_softc *sc)
690 {
691 	struct tty *tp = sc->sc_tty;
692 
693 	mutex_spin_enter(&sc->sc_lock);
694 
695 	/* If we were asserting flow control, then deassert it. */
696 	SET(sc->sc_rx_flags, RX_IBUF_BLOCKED);
697 	com_hwiflow(sc);
698 
699 	/* Clear any break condition set with TIOCSBRK. */
700 	com_break(sc, 0);
701 
702 	/*
703 	 * Hang up if necessary.  Wait a bit, so the other side has time to
704 	 * notice even if we immediately open the port again.
705 	 * Avoid tsleeping above splhigh().
706 	 */
707 	if (ISSET(tp->t_cflag, HUPCL)) {
708 		com_modem(sc, 0);
709 		mutex_spin_exit(&sc->sc_lock);
710 		/* XXX will only timeout */
711 		(void) kpause(ttclos, false, hz, NULL);
712 		mutex_spin_enter(&sc->sc_lock);
713 	}
714 
715 	/* Turn off interrupts. */
716 	if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
717 		sc->sc_ier = IER_ERXRDY; /* interrupt on break */
718 		if (sc->sc_type == COM_TYPE_PXA2x0)
719 			sc->sc_ier |= IER_ERXTOUT;
720 	} else
721 		sc->sc_ier = 0;
722 
723 	if (sc->sc_type == COM_TYPE_PXA2x0)
724 		sc->sc_ier |= IER_EUART;
725 
726 	CSR_WRITE_1(&sc->sc_regs, COM_REG_IER, sc->sc_ier);
727 
728 	mutex_spin_exit(&sc->sc_lock);
729 
730 	if (sc->disable) {
731 #ifdef DIAGNOSTIC
732 		if (!sc->enabled)
733 			panic("com_shutdown: not enabled?");
734 #endif
735 		(*sc->disable)(sc);
736 		sc->enabled = 0;
737 	}
738 }
739 
740 int
741 comopen(dev_t dev, int flag, int mode, struct lwp *l)
742 {
743 	struct com_softc *sc;
744 	struct tty *tp;
745 	int s;
746 	int error;
747 
748 	sc = device_lookup_private(&com_cd, COMUNIT(dev));
749 	if (sc == NULL || !ISSET(sc->sc_hwflags, COM_HW_DEV_OK) ||
750 		sc->sc_rbuf == NULL)
751 		return (ENXIO);
752 
753 	if (!device_is_active(sc->sc_dev))
754 		return (ENXIO);
755 
756 #ifdef KGDB
757 	/*
758 	 * If this is the kgdb port, no other use is permitted.
759 	 */
760 	if (ISSET(sc->sc_hwflags, COM_HW_KGDB))
761 		return (EBUSY);
762 #endif
763 
764 	tp = sc->sc_tty;
765 
766 	if (kauth_authorize_device_tty(l->l_cred, KAUTH_DEVICE_TTY_OPEN, tp))
767 		return (EBUSY);
768 
769 	s = spltty();
770 
771 	/*
772 	 * Do the following iff this is a first open.
773 	 */
774 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
775 		struct termios t;
776 
777 		tp->t_dev = dev;
778 
779 
780 		if (sc->enable) {
781 			if ((*sc->enable)(sc)) {
782 				splx(s);
783 				aprint_error_dev(sc->sc_dev,
784 				    "device enable failed\n");
785 				return (EIO);
786 			}
787 			mutex_spin_enter(&sc->sc_lock);
788 			sc->enabled = 1;
789 			com_config(sc);
790 		} else {
791 			mutex_spin_enter(&sc->sc_lock);
792 		}
793 
794 		/* Turn on interrupts. */
795 		sc->sc_ier = IER_ERXRDY | IER_ERLS | IER_EMSC;
796 		if (sc->sc_type == COM_TYPE_PXA2x0)
797 			sc->sc_ier |= IER_EUART | IER_ERXTOUT;
798 		CSR_WRITE_1(&sc->sc_regs, COM_REG_IER, sc->sc_ier);
799 
800 		/* Fetch the current modem control status, needed later. */
801 		sc->sc_msr = CSR_READ_1(&sc->sc_regs, COM_REG_MSR);
802 
803 		/* Clear PPS capture state on first open. */
804 		mutex_spin_enter(&timecounter_lock);
805 		memset(&sc->sc_pps_state, 0, sizeof(sc->sc_pps_state));
806 		sc->sc_pps_state.ppscap = PPS_CAPTUREASSERT | PPS_CAPTURECLEAR;
807 		pps_init(&sc->sc_pps_state);
808 		mutex_spin_exit(&timecounter_lock);
809 
810 		mutex_spin_exit(&sc->sc_lock);
811 
812 		/*
813 		 * Initialize the termios status to the defaults.  Add in the
814 		 * sticky bits from TIOCSFLAGS.
815 		 */
816 		if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
817 			t.c_ospeed = comconsrate;
818 			t.c_cflag = comconscflag;
819 		} else {
820 			t.c_ospeed = TTYDEF_SPEED;
821 			t.c_cflag = TTYDEF_CFLAG;
822 		}
823 		t.c_ispeed = t.c_ospeed;
824 		if (ISSET(sc->sc_swflags, TIOCFLAG_CLOCAL))
825 			SET(t.c_cflag, CLOCAL);
826 		if (ISSET(sc->sc_swflags, TIOCFLAG_CRTSCTS))
827 			SET(t.c_cflag, CRTSCTS);
828 		if (ISSET(sc->sc_swflags, TIOCFLAG_MDMBUF))
829 			SET(t.c_cflag, MDMBUF);
830 		/* Make sure comparam() will do something. */
831 		tp->t_ospeed = 0;
832 		(void) comparam(tp, &t);
833 		tp->t_iflag = TTYDEF_IFLAG;
834 		tp->t_oflag = TTYDEF_OFLAG;
835 		tp->t_lflag = TTYDEF_LFLAG;
836 		ttychars(tp);
837 		ttsetwater(tp);
838 
839 		mutex_spin_enter(&sc->sc_lock);
840 
841 		/*
842 		 * Turn on DTR.  We must always do this, even if carrier is not
843 		 * present, because otherwise we'd have to use TIOCSDTR
844 		 * immediately after setting CLOCAL, which applications do not
845 		 * expect.  We always assert DTR while the device is open
846 		 * unless explicitly requested to deassert it.
847 		 */
848 		com_modem(sc, 1);
849 
850 		/* Clear the input ring, and unblock. */
851 		sc->sc_rbput = sc->sc_rbget = sc->sc_rbuf;
852 		sc->sc_rbavail = com_rbuf_size;
853 		com_iflush(sc);
854 		CLR(sc->sc_rx_flags, RX_ANY_BLOCK);
855 		com_hwiflow(sc);
856 
857 #ifdef COM_DEBUG
858 		if (com_debug)
859 			comstatus(sc, "comopen  ");
860 #endif
861 
862 		mutex_spin_exit(&sc->sc_lock);
863 	}
864 
865 	splx(s);
866 
867 	error = ttyopen(tp, COMDIALOUT(dev), ISSET(flag, O_NONBLOCK));
868 	if (error)
869 		goto bad;
870 
871 	error = (*tp->t_linesw->l_open)(dev, tp);
872 	if (error)
873 		goto bad;
874 
875 	return (0);
876 
877 bad:
878 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
879 		/*
880 		 * We failed to open the device, and nobody else had it opened.
881 		 * Clean up the state as appropriate.
882 		 */
883 		com_shutdown(sc);
884 	}
885 
886 	return (error);
887 }
888 
889 int
890 comclose(dev_t dev, int flag, int mode, struct lwp *l)
891 {
892 	struct com_softc *sc =
893 	    device_lookup_private(&com_cd, COMUNIT(dev));
894 	struct tty *tp = sc->sc_tty;
895 
896 	/* XXX This is for cons.c. */
897 	if (!ISSET(tp->t_state, TS_ISOPEN))
898 		return (0);
899 
900 	(*tp->t_linesw->l_close)(tp, flag);
901 	ttyclose(tp);
902 
903 	if (COM_ISALIVE(sc) == 0)
904 		return (0);
905 
906 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
907 		/*
908 		 * Although we got a last close, the device may still be in
909 		 * use; e.g. if this was the dialout node, and there are still
910 		 * processes waiting for carrier on the non-dialout node.
911 		 */
912 		com_shutdown(sc);
913 	}
914 
915 	return (0);
916 }
917 
918 int
919 comread(dev_t dev, struct uio *uio, int flag)
920 {
921 	struct com_softc *sc =
922 	    device_lookup_private(&com_cd, COMUNIT(dev));
923 	struct tty *tp = sc->sc_tty;
924 
925 	if (COM_ISALIVE(sc) == 0)
926 		return (EIO);
927 
928 	return ((*tp->t_linesw->l_read)(tp, uio, flag));
929 }
930 
931 int
932 comwrite(dev_t dev, struct uio *uio, int flag)
933 {
934 	struct com_softc *sc =
935 	    device_lookup_private(&com_cd, COMUNIT(dev));
936 	struct tty *tp = sc->sc_tty;
937 
938 	if (COM_ISALIVE(sc) == 0)
939 		return (EIO);
940 
941 	return ((*tp->t_linesw->l_write)(tp, uio, flag));
942 }
943 
944 int
945 compoll(dev_t dev, int events, struct lwp *l)
946 {
947 	struct com_softc *sc =
948 	    device_lookup_private(&com_cd, COMUNIT(dev));
949 	struct tty *tp = sc->sc_tty;
950 
951 	if (COM_ISALIVE(sc) == 0)
952 		return (POLLHUP);
953 
954 	return ((*tp->t_linesw->l_poll)(tp, events, l));
955 }
956 
957 struct tty *
958 comtty(dev_t dev)
959 {
960 	struct com_softc *sc =
961 	    device_lookup_private(&com_cd, COMUNIT(dev));
962 	struct tty *tp = sc->sc_tty;
963 
964 	return (tp);
965 }
966 
967 int
968 comioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l)
969 {
970 	struct com_softc *sc;
971 	struct tty *tp;
972 	int error;
973 
974 	sc = device_lookup_private(&com_cd, COMUNIT(dev));
975 	if (sc == NULL)
976 		return ENXIO;
977 	if (COM_ISALIVE(sc) == 0)
978 		return (EIO);
979 
980 	tp = sc->sc_tty;
981 
982 	error = (*tp->t_linesw->l_ioctl)(tp, cmd, data, flag, l);
983 	if (error != EPASSTHROUGH)
984 		return (error);
985 
986 	error = ttioctl(tp, cmd, data, flag, l);
987 	if (error != EPASSTHROUGH)
988 		return (error);
989 
990 	error = 0;
991 	switch (cmd) {
992 	case TIOCSFLAGS:
993 		error = kauth_authorize_device_tty(l->l_cred,
994 		    KAUTH_DEVICE_TTY_PRIVSET, tp);
995 		break;
996 	default:
997 		/* nothing */
998 		break;
999 	}
1000 	if (error) {
1001 		return error;
1002 	}
1003 
1004 	mutex_spin_enter(&sc->sc_lock);
1005 
1006 	switch (cmd) {
1007 	case TIOCSBRK:
1008 		com_break(sc, 1);
1009 		break;
1010 
1011 	case TIOCCBRK:
1012 		com_break(sc, 0);
1013 		break;
1014 
1015 	case TIOCSDTR:
1016 		com_modem(sc, 1);
1017 		break;
1018 
1019 	case TIOCCDTR:
1020 		com_modem(sc, 0);
1021 		break;
1022 
1023 	case TIOCGFLAGS:
1024 		*(int *)data = sc->sc_swflags;
1025 		break;
1026 
1027 	case TIOCSFLAGS:
1028 		sc->sc_swflags = *(int *)data;
1029 		break;
1030 
1031 	case TIOCMSET:
1032 	case TIOCMBIS:
1033 	case TIOCMBIC:
1034 		tiocm_to_com(sc, cmd, *(int *)data);
1035 		break;
1036 
1037 	case TIOCMGET:
1038 		*(int *)data = com_to_tiocm(sc);
1039 		break;
1040 
1041 	case PPS_IOC_CREATE:
1042 	case PPS_IOC_DESTROY:
1043 	case PPS_IOC_GETPARAMS:
1044 	case PPS_IOC_SETPARAMS:
1045 	case PPS_IOC_GETCAP:
1046 	case PPS_IOC_FETCH:
1047 #ifdef PPS_SYNC
1048 	case PPS_IOC_KCBIND:
1049 #endif
1050 		mutex_spin_enter(&timecounter_lock);
1051 		error = pps_ioctl(cmd, data, &sc->sc_pps_state);
1052 		mutex_spin_exit(&timecounter_lock);
1053 		break;
1054 
1055 	case TIOCDCDTIMESTAMP:	/* XXX old, overloaded  API used by xntpd v3 */
1056 		mutex_spin_enter(&timecounter_lock);
1057 #ifndef PPS_TRAILING_EDGE
1058 		TIMESPEC_TO_TIMEVAL((struct timeval *)data,
1059 		    &sc->sc_pps_state.ppsinfo.assert_timestamp);
1060 #else
1061 		TIMESPEC_TO_TIMEVAL((struct timeval *)data,
1062 		    &sc->sc_pps_state.ppsinfo.clear_timestamp);
1063 #endif
1064 		mutex_spin_exit(&timecounter_lock);
1065 		break;
1066 
1067 	default:
1068 		error = EPASSTHROUGH;
1069 		break;
1070 	}
1071 
1072 	mutex_spin_exit(&sc->sc_lock);
1073 
1074 #ifdef COM_DEBUG
1075 	if (com_debug)
1076 		comstatus(sc, "comioctl ");
1077 #endif
1078 
1079 	return (error);
1080 }
1081 
1082 integrate void
1083 com_schedrx(struct com_softc *sc)
1084 {
1085 
1086 	sc->sc_rx_ready = 1;
1087 
1088 	/* Wake up the poller. */
1089 	softint_schedule(sc->sc_si);
1090 }
1091 
1092 void
1093 com_break(struct com_softc *sc, int onoff)
1094 {
1095 
1096 	if (onoff)
1097 		SET(sc->sc_lcr, LCR_SBREAK);
1098 	else
1099 		CLR(sc->sc_lcr, LCR_SBREAK);
1100 
1101 	if (!sc->sc_heldchange) {
1102 		if (sc->sc_tx_busy) {
1103 			sc->sc_heldtbc = sc->sc_tbc;
1104 			sc->sc_tbc = 0;
1105 			sc->sc_heldchange = 1;
1106 		} else
1107 			com_loadchannelregs(sc);
1108 	}
1109 }
1110 
1111 void
1112 com_modem(struct com_softc *sc, int onoff)
1113 {
1114 
1115 	if (sc->sc_mcr_dtr == 0)
1116 		return;
1117 
1118 	if (onoff)
1119 		SET(sc->sc_mcr, sc->sc_mcr_dtr);
1120 	else
1121 		CLR(sc->sc_mcr, sc->sc_mcr_dtr);
1122 
1123 	if (!sc->sc_heldchange) {
1124 		if (sc->sc_tx_busy) {
1125 			sc->sc_heldtbc = sc->sc_tbc;
1126 			sc->sc_tbc = 0;
1127 			sc->sc_heldchange = 1;
1128 		} else
1129 			com_loadchannelregs(sc);
1130 	}
1131 }
1132 
1133 void
1134 tiocm_to_com(struct com_softc *sc, u_long how, int ttybits)
1135 {
1136 	u_char combits;
1137 
1138 	combits = 0;
1139 	if (ISSET(ttybits, TIOCM_DTR))
1140 		SET(combits, MCR_DTR);
1141 	if (ISSET(ttybits, TIOCM_RTS))
1142 		SET(combits, MCR_RTS);
1143 
1144 	switch (how) {
1145 	case TIOCMBIC:
1146 		CLR(sc->sc_mcr, combits);
1147 		break;
1148 
1149 	case TIOCMBIS:
1150 		SET(sc->sc_mcr, combits);
1151 		break;
1152 
1153 	case TIOCMSET:
1154 		CLR(sc->sc_mcr, MCR_DTR | MCR_RTS);
1155 		SET(sc->sc_mcr, combits);
1156 		break;
1157 	}
1158 
1159 	if (!sc->sc_heldchange) {
1160 		if (sc->sc_tx_busy) {
1161 			sc->sc_heldtbc = sc->sc_tbc;
1162 			sc->sc_tbc = 0;
1163 			sc->sc_heldchange = 1;
1164 		} else
1165 			com_loadchannelregs(sc);
1166 	}
1167 }
1168 
1169 int
1170 com_to_tiocm(struct com_softc *sc)
1171 {
1172 	u_char combits;
1173 	int ttybits = 0;
1174 
1175 	combits = sc->sc_mcr;
1176 	if (ISSET(combits, MCR_DTR))
1177 		SET(ttybits, TIOCM_DTR);
1178 	if (ISSET(combits, MCR_RTS))
1179 		SET(ttybits, TIOCM_RTS);
1180 
1181 	combits = sc->sc_msr;
1182 	if (ISSET(combits, MSR_DCD))
1183 		SET(ttybits, TIOCM_CD);
1184 	if (ISSET(combits, MSR_CTS))
1185 		SET(ttybits, TIOCM_CTS);
1186 	if (ISSET(combits, MSR_DSR))
1187 		SET(ttybits, TIOCM_DSR);
1188 	if (ISSET(combits, MSR_RI | MSR_TERI))
1189 		SET(ttybits, TIOCM_RI);
1190 
1191 	if (ISSET(sc->sc_ier, IER_ERXRDY | IER_ETXRDY | IER_ERLS | IER_EMSC))
1192 		SET(ttybits, TIOCM_LE);
1193 
1194 	return (ttybits);
1195 }
1196 
1197 static u_char
1198 cflag2lcr(tcflag_t cflag)
1199 {
1200 	u_char lcr = 0;
1201 
1202 	switch (ISSET(cflag, CSIZE)) {
1203 	case CS5:
1204 		SET(lcr, LCR_5BITS);
1205 		break;
1206 	case CS6:
1207 		SET(lcr, LCR_6BITS);
1208 		break;
1209 	case CS7:
1210 		SET(lcr, LCR_7BITS);
1211 		break;
1212 	case CS8:
1213 		SET(lcr, LCR_8BITS);
1214 		break;
1215 	}
1216 	if (ISSET(cflag, PARENB)) {
1217 		SET(lcr, LCR_PENAB);
1218 		if (!ISSET(cflag, PARODD))
1219 			SET(lcr, LCR_PEVEN);
1220 	}
1221 	if (ISSET(cflag, CSTOPB))
1222 		SET(lcr, LCR_STOPB);
1223 
1224 	return (lcr);
1225 }
1226 
1227 int
1228 comparam(struct tty *tp, struct termios *t)
1229 {
1230 	struct com_softc *sc =
1231 	    device_lookup_private(&com_cd, COMUNIT(tp->t_dev));
1232 	int ospeed;
1233 	u_char lcr;
1234 
1235 	if (COM_ISALIVE(sc) == 0)
1236 		return (EIO);
1237 
1238 #ifdef COM_HAYESP
1239 	if (sc->sc_type == COM_TYPE_HAYESP) {
1240 		int prescaler, speed;
1241 
1242 		/*
1243 		 * Calculate UART clock prescaler.  It should be in
1244 		 * range of 0 .. 3.
1245 		 */
1246 		for (prescaler = 0, speed = t->c_ospeed; prescaler < 4;
1247 		    prescaler++, speed /= 2)
1248 			if ((ospeed = comspeed(speed, sc->sc_frequency,
1249 					       sc->sc_type)) > 0)
1250 				break;
1251 
1252 		if (prescaler == 4)
1253 			return (EINVAL);
1254 		sc->sc_prescaler = prescaler;
1255 	} else
1256 #endif
1257 	ospeed = comspeed(t->c_ospeed, sc->sc_frequency, sc->sc_type);
1258 
1259 	/* Check requested parameters. */
1260 	if (ospeed < 0)
1261 		return (EINVAL);
1262 	if (t->c_ispeed && t->c_ispeed != t->c_ospeed)
1263 		return (EINVAL);
1264 
1265 	/*
1266 	 * For the console, always force CLOCAL and !HUPCL, so that the port
1267 	 * is always active.
1268 	 */
1269 	if (ISSET(sc->sc_swflags, TIOCFLAG_SOFTCAR) ||
1270 	    ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
1271 		SET(t->c_cflag, CLOCAL);
1272 		CLR(t->c_cflag, HUPCL);
1273 	}
1274 
1275 	/*
1276 	 * If there were no changes, don't do anything.  This avoids dropping
1277 	 * input and improves performance when all we did was frob things like
1278 	 * VMIN and VTIME.
1279 	 */
1280 	if (tp->t_ospeed == t->c_ospeed &&
1281 	    tp->t_cflag == t->c_cflag)
1282 		return (0);
1283 
1284 	lcr = ISSET(sc->sc_lcr, LCR_SBREAK) | cflag2lcr(t->c_cflag);
1285 
1286 	mutex_spin_enter(&sc->sc_lock);
1287 
1288 	sc->sc_lcr = lcr;
1289 
1290 	/*
1291 	 * If we're not in a mode that assumes a connection is present, then
1292 	 * ignore carrier changes.
1293 	 */
1294 	if (ISSET(t->c_cflag, CLOCAL | MDMBUF))
1295 		sc->sc_msr_dcd = 0;
1296 	else
1297 		sc->sc_msr_dcd = MSR_DCD;
1298 	/*
1299 	 * Set the flow control pins depending on the current flow control
1300 	 * mode.
1301 	 */
1302 	if (ISSET(t->c_cflag, CRTSCTS)) {
1303 		sc->sc_mcr_dtr = MCR_DTR;
1304 		sc->sc_mcr_rts = MCR_RTS;
1305 		sc->sc_msr_cts = MSR_CTS;
1306 		sc->sc_efr = EFR_AUTORTS | EFR_AUTOCTS;
1307 	} else if (ISSET(t->c_cflag, MDMBUF)) {
1308 		/*
1309 		 * For DTR/DCD flow control, make sure we don't toggle DTR for
1310 		 * carrier detection.
1311 		 */
1312 		sc->sc_mcr_dtr = 0;
1313 		sc->sc_mcr_rts = MCR_DTR;
1314 		sc->sc_msr_cts = MSR_DCD;
1315 		sc->sc_efr = 0;
1316 	} else {
1317 		/*
1318 		 * If no flow control, then always set RTS.  This will make
1319 		 * the other side happy if it mistakenly thinks we're doing
1320 		 * RTS/CTS flow control.
1321 		 */
1322 		sc->sc_mcr_dtr = MCR_DTR | MCR_RTS;
1323 		sc->sc_mcr_rts = 0;
1324 		sc->sc_msr_cts = 0;
1325 		sc->sc_efr = 0;
1326 		if (ISSET(sc->sc_mcr, MCR_DTR))
1327 			SET(sc->sc_mcr, MCR_RTS);
1328 		else
1329 			CLR(sc->sc_mcr, MCR_RTS);
1330 	}
1331 	sc->sc_msr_mask = sc->sc_msr_cts | sc->sc_msr_dcd;
1332 
1333 #if 0
1334 	if (ospeed == 0)
1335 		CLR(sc->sc_mcr, sc->sc_mcr_dtr);
1336 	else
1337 		SET(sc->sc_mcr, sc->sc_mcr_dtr);
1338 #endif
1339 
1340 	sc->sc_dlbl = ospeed;
1341 	sc->sc_dlbh = ospeed >> 8;
1342 
1343 	/*
1344 	 * Set the FIFO threshold based on the receive speed.
1345 	 *
1346 	 *  * If it's a low speed, it's probably a mouse or some other
1347 	 *    interactive device, so set the threshold low.
1348 	 *  * If it's a high speed, trim the trigger level down to prevent
1349 	 *    overflows.
1350 	 *  * Otherwise set it a bit higher.
1351 	 */
1352 	if (sc->sc_type == COM_TYPE_HAYESP)
1353 		sc->sc_fifo = FIFO_DMA_MODE | FIFO_ENABLE | FIFO_TRIGGER_8;
1354 	else if (ISSET(sc->sc_hwflags, COM_HW_FIFO)) {
1355 		if (t->c_ospeed <= 1200)
1356 			sc->sc_fifo = FIFO_ENABLE | FIFO_TRIGGER_1;
1357 		else if (t->c_ospeed <= 38400)
1358 			sc->sc_fifo = FIFO_ENABLE | FIFO_TRIGGER_8;
1359 		else
1360 			sc->sc_fifo = FIFO_ENABLE | FIFO_TRIGGER_4;
1361 	} else
1362 		sc->sc_fifo = 0;
1363 
1364 	/* And copy to tty. */
1365 	tp->t_ispeed = t->c_ospeed;
1366 	tp->t_ospeed = t->c_ospeed;
1367 	tp->t_cflag = t->c_cflag;
1368 
1369 	if (!sc->sc_heldchange) {
1370 		if (sc->sc_tx_busy) {
1371 			sc->sc_heldtbc = sc->sc_tbc;
1372 			sc->sc_tbc = 0;
1373 			sc->sc_heldchange = 1;
1374 		} else
1375 			com_loadchannelregs(sc);
1376 	}
1377 
1378 	if (!ISSET(t->c_cflag, CHWFLOW)) {
1379 		/* Disable the high water mark. */
1380 		sc->sc_r_hiwat = 0;
1381 		sc->sc_r_lowat = 0;
1382 		if (ISSET(sc->sc_rx_flags, RX_TTY_OVERFLOWED)) {
1383 			CLR(sc->sc_rx_flags, RX_TTY_OVERFLOWED);
1384 			com_schedrx(sc);
1385 		}
1386 		if (ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED|RX_IBUF_BLOCKED)) {
1387 			CLR(sc->sc_rx_flags, RX_TTY_BLOCKED|RX_IBUF_BLOCKED);
1388 			com_hwiflow(sc);
1389 		}
1390 	} else {
1391 		sc->sc_r_hiwat = com_rbuf_hiwat;
1392 		sc->sc_r_lowat = com_rbuf_lowat;
1393 	}
1394 
1395 	mutex_spin_exit(&sc->sc_lock);
1396 
1397 	/*
1398 	 * Update the tty layer's idea of the carrier bit, in case we changed
1399 	 * CLOCAL or MDMBUF.  We don't hang up here; we only do that by
1400 	 * explicit request.
1401 	 */
1402 	(void) (*tp->t_linesw->l_modem)(tp, ISSET(sc->sc_msr, MSR_DCD));
1403 
1404 #ifdef COM_DEBUG
1405 	if (com_debug)
1406 		comstatus(sc, "comparam ");
1407 #endif
1408 
1409 	if (!ISSET(t->c_cflag, CHWFLOW)) {
1410 		if (sc->sc_tx_stopped) {
1411 			sc->sc_tx_stopped = 0;
1412 			comstart(tp);
1413 		}
1414 	}
1415 
1416 	return (0);
1417 }
1418 
1419 void
1420 com_iflush(struct com_softc *sc)
1421 {
1422 	struct com_regs	*regsp = &sc->sc_regs;
1423 #ifdef DIAGNOSTIC
1424 	int reg;
1425 #endif
1426 	int timo;
1427 
1428 #ifdef DIAGNOSTIC
1429 	reg = 0xffff;
1430 #endif
1431 	timo = 50000;
1432 	/* flush any pending I/O */
1433 	while (ISSET(CSR_READ_1(regsp, COM_REG_LSR), LSR_RXRDY)
1434 	    && --timo)
1435 #ifdef DIAGNOSTIC
1436 		reg =
1437 #else
1438 		    (void)
1439 #endif
1440 		    CSR_READ_1(regsp, COM_REG_RXDATA);
1441 #ifdef DIAGNOSTIC
1442 	if (!timo)
1443 		aprint_error_dev(sc->sc_dev, "com_iflush timeout %02x\n", reg);
1444 #endif
1445 }
1446 
1447 void
1448 com_loadchannelregs(struct com_softc *sc)
1449 {
1450 	struct com_regs *regsp = &sc->sc_regs;
1451 
1452 	/* XXXXX necessary? */
1453 	com_iflush(sc);
1454 
1455 	if (sc->sc_type == COM_TYPE_PXA2x0)
1456 		CSR_WRITE_1(regsp, COM_REG_IER, IER_EUART);
1457 	else
1458 		CSR_WRITE_1(regsp, COM_REG_IER, 0);
1459 
1460 	if (sc->sc_type == COM_TYPE_OMAP) {
1461 		/* disable before changing settings */
1462 		CSR_WRITE_1(regsp, COM_REG_MDR1, MDR1_MODE_DISABLE);
1463 	}
1464 
1465 	if (ISSET(sc->sc_hwflags, COM_HW_FLOW)) {
1466 		if (sc->sc_type != COM_TYPE_AU1x00) {	/* no EFR on alchemy */
1467 			CSR_WRITE_1(regsp, COM_REG_EFR, sc->sc_efr);
1468 			CSR_WRITE_1(regsp, COM_REG_LCR, LCR_EERS);
1469 		}
1470 	}
1471 	if (sc->sc_type == COM_TYPE_AU1x00) {
1472 		/* alchemy has single separate 16-bit clock divisor register */
1473 		CSR_WRITE_2(regsp, COM_REG_DLBL, sc->sc_dlbl +
1474 		    (sc->sc_dlbh << 8));
1475 	} else {
1476 		CSR_WRITE_1(regsp, COM_REG_LCR, sc->sc_lcr | LCR_DLAB);
1477 		CSR_WRITE_1(regsp, COM_REG_DLBL, sc->sc_dlbl);
1478 		CSR_WRITE_1(regsp, COM_REG_DLBH, sc->sc_dlbh);
1479 	}
1480 	CSR_WRITE_1(regsp, COM_REG_LCR, sc->sc_lcr);
1481 	CSR_WRITE_1(regsp, COM_REG_MCR, sc->sc_mcr_active = sc->sc_mcr);
1482 	CSR_WRITE_1(regsp, COM_REG_FIFO, sc->sc_fifo);
1483 #ifdef COM_HAYESP
1484 	if (sc->sc_type == COM_TYPE_HAYESP) {
1485 		bus_space_write_1(regsp->cr_iot, sc->sc_hayespioh, HAYESP_CMD1,
1486 		    HAYESP_SETPRESCALER);
1487 		bus_space_write_1(regsp->cr_iot, sc->sc_hayespioh, HAYESP_CMD2,
1488 		    sc->sc_prescaler);
1489 	}
1490 #endif
1491 	if (sc->sc_type == COM_TYPE_OMAP) {
1492 		/* setup the fifos.  the FCR value is not used as long
1493 		   as SCR[6] and SCR[7] are 0, which they are at reset
1494 		   and we never touch the SCR register */
1495 		uint8_t rx_fifo_trig = 40;
1496 		uint8_t tx_fifo_trig = 60;
1497 		uint8_t rx_start = 8;
1498 		uint8_t rx_halt = 60;
1499 		uint8_t tlr_value = ((rx_fifo_trig>>2) << 4) | (tx_fifo_trig>>2);
1500 		uint8_t tcr_value = ((rx_start>>2) << 4) | (rx_halt>>2);
1501 
1502 		/* enable access to TCR & TLR */
1503 		CSR_WRITE_1(regsp, COM_REG_MCR, sc->sc_mcr | MCR_TCR_TLR);
1504 
1505 		/* write tcr and tlr values */
1506 		CSR_WRITE_1(regsp, COM_REG_TLR, tlr_value);
1507 		CSR_WRITE_1(regsp, COM_REG_TCR, tcr_value);
1508 
1509 		/* disable access to TCR & TLR */
1510 		CSR_WRITE_1(regsp, COM_REG_MCR, sc->sc_mcr);
1511 
1512 		/* enable again, but mode is based on speed */
1513 		if (sc->sc_tty->t_termios.c_ospeed > 230400) {
1514 			CSR_WRITE_1(regsp, COM_REG_MDR1, MDR1_MODE_UART_13X);
1515 		} else {
1516 			CSR_WRITE_1(regsp, COM_REG_MDR1, MDR1_MODE_UART_16X);
1517 		}
1518 	}
1519 
1520 	CSR_WRITE_1(regsp, COM_REG_IER, sc->sc_ier);
1521 }
1522 
1523 int
1524 comhwiflow(struct tty *tp, int block)
1525 {
1526 	struct com_softc *sc =
1527 	    device_lookup_private(&com_cd, COMUNIT(tp->t_dev));
1528 
1529 	if (COM_ISALIVE(sc) == 0)
1530 		return (0);
1531 
1532 	if (sc->sc_mcr_rts == 0)
1533 		return (0);
1534 
1535 	mutex_spin_enter(&sc->sc_lock);
1536 
1537 	if (block) {
1538 		if (!ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED)) {
1539 			SET(sc->sc_rx_flags, RX_TTY_BLOCKED);
1540 			com_hwiflow(sc);
1541 		}
1542 	} else {
1543 		if (ISSET(sc->sc_rx_flags, RX_TTY_OVERFLOWED)) {
1544 			CLR(sc->sc_rx_flags, RX_TTY_OVERFLOWED);
1545 			com_schedrx(sc);
1546 		}
1547 		if (ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED)) {
1548 			CLR(sc->sc_rx_flags, RX_TTY_BLOCKED);
1549 			com_hwiflow(sc);
1550 		}
1551 	}
1552 
1553 	mutex_spin_exit(&sc->sc_lock);
1554 	return (1);
1555 }
1556 
1557 /*
1558  * (un)block input via hw flowcontrol
1559  */
1560 void
1561 com_hwiflow(struct com_softc *sc)
1562 {
1563 	struct com_regs *regsp= &sc->sc_regs;
1564 
1565 	if (sc->sc_mcr_rts == 0)
1566 		return;
1567 
1568 	if (ISSET(sc->sc_rx_flags, RX_ANY_BLOCK)) {
1569 		CLR(sc->sc_mcr, sc->sc_mcr_rts);
1570 		CLR(sc->sc_mcr_active, sc->sc_mcr_rts);
1571 	} else {
1572 		SET(sc->sc_mcr, sc->sc_mcr_rts);
1573 		SET(sc->sc_mcr_active, sc->sc_mcr_rts);
1574 	}
1575 	CSR_WRITE_1(regsp, COM_REG_MCR, sc->sc_mcr_active);
1576 }
1577 
1578 
1579 void
1580 comstart(struct tty *tp)
1581 {
1582 	struct com_softc *sc =
1583 	    device_lookup_private(&com_cd, COMUNIT(tp->t_dev));
1584 	struct com_regs *regsp = &sc->sc_regs;
1585 	int s;
1586 
1587 	if (COM_ISALIVE(sc) == 0)
1588 		return;
1589 
1590 	s = spltty();
1591 	if (ISSET(tp->t_state, TS_BUSY | TS_TIMEOUT | TS_TTSTOP))
1592 		goto out;
1593 	if (sc->sc_tx_stopped)
1594 		goto out;
1595 	if (!ttypull(tp))
1596 		goto out;
1597 
1598 	/* Grab the first contiguous region of buffer space. */
1599 	{
1600 		u_char *tba;
1601 		int tbc;
1602 
1603 		tba = tp->t_outq.c_cf;
1604 		tbc = ndqb(&tp->t_outq, 0);
1605 
1606 		mutex_spin_enter(&sc->sc_lock);
1607 
1608 		sc->sc_tba = tba;
1609 		sc->sc_tbc = tbc;
1610 	}
1611 
1612 	SET(tp->t_state, TS_BUSY);
1613 	sc->sc_tx_busy = 1;
1614 
1615 	/* Enable transmit completion interrupts if necessary. */
1616 	if (!ISSET(sc->sc_ier, IER_ETXRDY)) {
1617 		SET(sc->sc_ier, IER_ETXRDY);
1618 		CSR_WRITE_1(regsp, COM_REG_IER, sc->sc_ier);
1619 	}
1620 
1621 	/* Output the first chunk of the contiguous buffer. */
1622 	if (!ISSET(sc->sc_hwflags, COM_HW_NO_TXPRELOAD)) {
1623 		u_int n;
1624 
1625 		n = sc->sc_tbc;
1626 		if (n > sc->sc_fifolen)
1627 			n = sc->sc_fifolen;
1628 		CSR_WRITE_MULTI(regsp, COM_REG_TXDATA, sc->sc_tba, n);
1629 		sc->sc_tbc -= n;
1630 		sc->sc_tba += n;
1631 	}
1632 
1633 	mutex_spin_exit(&sc->sc_lock);
1634 out:
1635 	splx(s);
1636 	return;
1637 }
1638 
1639 /*
1640  * Stop output on a line.
1641  */
1642 void
1643 comstop(struct tty *tp, int flag)
1644 {
1645 	struct com_softc *sc =
1646 	    device_lookup_private(&com_cd, COMUNIT(tp->t_dev));
1647 
1648 	mutex_spin_enter(&sc->sc_lock);
1649 	if (ISSET(tp->t_state, TS_BUSY)) {
1650 		/* Stop transmitting at the next chunk. */
1651 		sc->sc_tbc = 0;
1652 		sc->sc_heldtbc = 0;
1653 		if (!ISSET(tp->t_state, TS_TTSTOP))
1654 			SET(tp->t_state, TS_FLUSH);
1655 	}
1656 	mutex_spin_exit(&sc->sc_lock);
1657 }
1658 
1659 void
1660 comdiag(void *arg)
1661 {
1662 	struct com_softc *sc = arg;
1663 	int overflows, floods;
1664 
1665 	mutex_spin_enter(&sc->sc_lock);
1666 	overflows = sc->sc_overflows;
1667 	sc->sc_overflows = 0;
1668 	floods = sc->sc_floods;
1669 	sc->sc_floods = 0;
1670 	sc->sc_errors = 0;
1671 	mutex_spin_exit(&sc->sc_lock);
1672 
1673 	log(LOG_WARNING, "%s: %d silo overflow%s, %d ibuf flood%s\n",
1674 	    device_xname(sc->sc_dev),
1675 	    overflows, overflows == 1 ? "" : "s",
1676 	    floods, floods == 1 ? "" : "s");
1677 }
1678 
1679 integrate void
1680 com_rxsoft(struct com_softc *sc, struct tty *tp)
1681 {
1682 	int (*rint)(int, struct tty *) = tp->t_linesw->l_rint;
1683 	u_char *get, *end;
1684 	u_int cc, scc;
1685 	u_char lsr;
1686 	int code;
1687 
1688 	end = sc->sc_ebuf;
1689 	get = sc->sc_rbget;
1690 	scc = cc = com_rbuf_size - sc->sc_rbavail;
1691 
1692 	if (cc == com_rbuf_size) {
1693 		sc->sc_floods++;
1694 		if (sc->sc_errors++ == 0)
1695 			callout_reset(&sc->sc_diag_callout, 60 * hz,
1696 			    comdiag, sc);
1697 	}
1698 
1699 	/* If not yet open, drop the entire buffer content here */
1700 	if (!ISSET(tp->t_state, TS_ISOPEN)) {
1701 		get += cc << 1;
1702 		if (get >= end)
1703 			get -= com_rbuf_size << 1;
1704 		cc = 0;
1705 	}
1706 	while (cc) {
1707 		code = get[0];
1708 		lsr = get[1];
1709 		if (ISSET(lsr, LSR_OE | LSR_BI | LSR_FE | LSR_PE)) {
1710 			if (ISSET(lsr, LSR_OE)) {
1711 				sc->sc_overflows++;
1712 				if (sc->sc_errors++ == 0)
1713 					callout_reset(&sc->sc_diag_callout,
1714 					    60 * hz, comdiag, sc);
1715 			}
1716 			if (ISSET(lsr, LSR_BI | LSR_FE))
1717 				SET(code, TTY_FE);
1718 			if (ISSET(lsr, LSR_PE))
1719 				SET(code, TTY_PE);
1720 		}
1721 		if ((*rint)(code, tp) == -1) {
1722 			/*
1723 			 * The line discipline's buffer is out of space.
1724 			 */
1725 			if (!ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED)) {
1726 				/*
1727 				 * We're either not using flow control, or the
1728 				 * line discipline didn't tell us to block for
1729 				 * some reason.  Either way, we have no way to
1730 				 * know when there's more space available, so
1731 				 * just drop the rest of the data.
1732 				 */
1733 				get += cc << 1;
1734 				if (get >= end)
1735 					get -= com_rbuf_size << 1;
1736 				cc = 0;
1737 			} else {
1738 				/*
1739 				 * Don't schedule any more receive processing
1740 				 * until the line discipline tells us there's
1741 				 * space available (through comhwiflow()).
1742 				 * Leave the rest of the data in the input
1743 				 * buffer.
1744 				 */
1745 				SET(sc->sc_rx_flags, RX_TTY_OVERFLOWED);
1746 			}
1747 			break;
1748 		}
1749 		get += 2;
1750 		if (get >= end)
1751 			get = sc->sc_rbuf;
1752 		cc--;
1753 	}
1754 
1755 	if (cc != scc) {
1756 		sc->sc_rbget = get;
1757 		mutex_spin_enter(&sc->sc_lock);
1758 
1759 		cc = sc->sc_rbavail += scc - cc;
1760 		/* Buffers should be ok again, release possible block. */
1761 		if (cc >= sc->sc_r_lowat) {
1762 			if (ISSET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED)) {
1763 				CLR(sc->sc_rx_flags, RX_IBUF_OVERFLOWED);
1764 				SET(sc->sc_ier, IER_ERXRDY);
1765 #ifdef COM_PXA2X0
1766 				if (sc->sc_type == COM_TYPE_PXA2x0)
1767 					SET(sc->sc_ier, IER_ERXTOUT);
1768 #endif
1769 				CSR_WRITE_1(&sc->sc_regs, COM_REG_IER, sc->sc_ier);
1770 			}
1771 			if (ISSET(sc->sc_rx_flags, RX_IBUF_BLOCKED)) {
1772 				CLR(sc->sc_rx_flags, RX_IBUF_BLOCKED);
1773 				com_hwiflow(sc);
1774 			}
1775 		}
1776 		mutex_spin_exit(&sc->sc_lock);
1777 	}
1778 }
1779 
1780 integrate void
1781 com_txsoft(struct com_softc *sc, struct tty *tp)
1782 {
1783 
1784 	CLR(tp->t_state, TS_BUSY);
1785 	if (ISSET(tp->t_state, TS_FLUSH))
1786 		CLR(tp->t_state, TS_FLUSH);
1787 	else
1788 		ndflush(&tp->t_outq, (int)(sc->sc_tba - tp->t_outq.c_cf));
1789 	(*tp->t_linesw->l_start)(tp);
1790 }
1791 
1792 integrate void
1793 com_stsoft(struct com_softc *sc, struct tty *tp)
1794 {
1795 	u_char msr, delta;
1796 
1797 	mutex_spin_enter(&sc->sc_lock);
1798 	msr = sc->sc_msr;
1799 	delta = sc->sc_msr_delta;
1800 	sc->sc_msr_delta = 0;
1801 	mutex_spin_exit(&sc->sc_lock);
1802 
1803 	if (ISSET(delta, sc->sc_msr_dcd)) {
1804 		/*
1805 		 * Inform the tty layer that carrier detect changed.
1806 		 */
1807 		(void) (*tp->t_linesw->l_modem)(tp, ISSET(msr, MSR_DCD));
1808 	}
1809 
1810 	if (ISSET(delta, sc->sc_msr_cts)) {
1811 		/* Block or unblock output according to flow control. */
1812 		if (ISSET(msr, sc->sc_msr_cts)) {
1813 			sc->sc_tx_stopped = 0;
1814 			(*tp->t_linesw->l_start)(tp);
1815 		} else {
1816 			sc->sc_tx_stopped = 1;
1817 		}
1818 	}
1819 
1820 #ifdef COM_DEBUG
1821 	if (com_debug)
1822 		comstatus(sc, "com_stsoft");
1823 #endif
1824 }
1825 
1826 void
1827 comsoft(void *arg)
1828 {
1829 	struct com_softc *sc = arg;
1830 	struct tty *tp;
1831 
1832 	if (COM_ISALIVE(sc) == 0)
1833 		return;
1834 
1835 	tp = sc->sc_tty;
1836 
1837 	if (sc->sc_rx_ready) {
1838 		sc->sc_rx_ready = 0;
1839 		com_rxsoft(sc, tp);
1840 	}
1841 
1842 	if (sc->sc_st_check) {
1843 		sc->sc_st_check = 0;
1844 		com_stsoft(sc, tp);
1845 	}
1846 
1847 	if (sc->sc_tx_done) {
1848 		sc->sc_tx_done = 0;
1849 		com_txsoft(sc, tp);
1850 	}
1851 }
1852 
1853 int
1854 comintr(void *arg)
1855 {
1856 	struct com_softc *sc = arg;
1857 	struct com_regs *regsp = &sc->sc_regs;
1858 
1859 	u_char *put, *end;
1860 	u_int cc;
1861 	u_char lsr, iir;
1862 
1863 	if (COM_ISALIVE(sc) == 0)
1864 		return (0);
1865 
1866 	mutex_spin_enter(&sc->sc_lock);
1867 	iir = CSR_READ_1(regsp, COM_REG_IIR);
1868 	if (ISSET(iir, IIR_NOPEND)) {
1869 		mutex_spin_exit(&sc->sc_lock);
1870 		return (0);
1871 	}
1872 
1873 	end = sc->sc_ebuf;
1874 	put = sc->sc_rbput;
1875 	cc = sc->sc_rbavail;
1876 
1877 again:	do {
1878 		u_char	msr, delta;
1879 
1880 		lsr = CSR_READ_1(regsp, COM_REG_LSR);
1881 		if (ISSET(lsr, LSR_BI)) {
1882 			int cn_trapped = 0;
1883 
1884 			cn_check_magic(sc->sc_tty->t_dev,
1885 				       CNC_BREAK, com_cnm_state);
1886 			if (cn_trapped)
1887 				continue;
1888 #if defined(KGDB) && !defined(DDB)
1889 			if (ISSET(sc->sc_hwflags, COM_HW_KGDB)) {
1890 				kgdb_connect(1);
1891 				continue;
1892 			}
1893 #endif
1894 		}
1895 
1896 		if (ISSET(lsr, LSR_RCV_MASK) &&
1897 		    !ISSET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED)) {
1898 			while (cc > 0) {
1899 				int cn_trapped = 0;
1900 				put[0] = CSR_READ_1(regsp, COM_REG_RXDATA);
1901 				put[1] = lsr;
1902 				cn_check_magic(sc->sc_tty->t_dev,
1903 					       put[0], com_cnm_state);
1904 				if (cn_trapped)
1905 					goto next;
1906 				put += 2;
1907 				if (put >= end)
1908 					put = sc->sc_rbuf;
1909 				cc--;
1910 			next:
1911 				lsr = CSR_READ_1(regsp, COM_REG_LSR);
1912 				if (!ISSET(lsr, LSR_RCV_MASK))
1913 					break;
1914 			}
1915 
1916 			/*
1917 			 * Current string of incoming characters ended because
1918 			 * no more data was available or we ran out of space.
1919 			 * Schedule a receive event if any data was received.
1920 			 * If we're out of space, turn off receive interrupts.
1921 			 */
1922 			sc->sc_rbput = put;
1923 			sc->sc_rbavail = cc;
1924 			if (!ISSET(sc->sc_rx_flags, RX_TTY_OVERFLOWED))
1925 				sc->sc_rx_ready = 1;
1926 
1927 			/*
1928 			 * See if we are in danger of overflowing a buffer. If
1929 			 * so, use hardware flow control to ease the pressure.
1930 			 */
1931 			if (!ISSET(sc->sc_rx_flags, RX_IBUF_BLOCKED) &&
1932 			    cc < sc->sc_r_hiwat) {
1933 				SET(sc->sc_rx_flags, RX_IBUF_BLOCKED);
1934 				com_hwiflow(sc);
1935 			}
1936 
1937 			/*
1938 			 * If we're out of space, disable receive interrupts
1939 			 * until the queue has drained a bit.
1940 			 */
1941 			if (!cc) {
1942 				SET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED);
1943 #ifdef COM_PXA2X0
1944 				if (sc->sc_type == COM_TYPE_PXA2x0)
1945 					CLR(sc->sc_ier, IER_ERXRDY|IER_ERXTOUT);
1946 				else
1947 #endif
1948 					CLR(sc->sc_ier, IER_ERXRDY);
1949 				CSR_WRITE_1(regsp, COM_REG_IER, sc->sc_ier);
1950 			}
1951 		} else {
1952 			if ((iir & (IIR_RXRDY|IIR_TXRDY)) == IIR_RXRDY) {
1953 				(void) CSR_READ_1(regsp, COM_REG_RXDATA);
1954 				continue;
1955 			}
1956 		}
1957 
1958 		msr = CSR_READ_1(regsp, COM_REG_MSR);
1959 		delta = msr ^ sc->sc_msr;
1960 		sc->sc_msr = msr;
1961 		if ((sc->sc_pps_state.ppsparam.mode & PPS_CAPTUREBOTH) &&
1962 		    (delta & MSR_DCD)) {
1963 			mutex_spin_enter(&timecounter_lock);
1964 			pps_capture(&sc->sc_pps_state);
1965 			pps_event(&sc->sc_pps_state,
1966 			    (msr & MSR_DCD) ?
1967 			    PPS_CAPTUREASSERT :
1968 			    PPS_CAPTURECLEAR);
1969 			mutex_spin_exit(&timecounter_lock);
1970 		}
1971 
1972 		/*
1973 		 * Process normal status changes
1974 		 */
1975 		if (ISSET(delta, sc->sc_msr_mask)) {
1976 			SET(sc->sc_msr_delta, delta);
1977 
1978 			/*
1979 			 * Stop output immediately if we lose the output
1980 			 * flow control signal or carrier detect.
1981 			 */
1982 			if (ISSET(~msr, sc->sc_msr_mask)) {
1983 				sc->sc_tbc = 0;
1984 				sc->sc_heldtbc = 0;
1985 #ifdef COM_DEBUG
1986 				if (com_debug)
1987 					comstatus(sc, "comintr  ");
1988 #endif
1989 			}
1990 
1991 			sc->sc_st_check = 1;
1992 		}
1993 	} while (!ISSET((iir =
1994 	    CSR_READ_1(regsp, COM_REG_IIR)), IIR_NOPEND) &&
1995 	    /*
1996 	     * Since some device (e.g., ST16C1550) doesn't clear IIR_TXRDY
1997 	     * by IIR read, so we can't do this way: `process all interrupts,
1998 	     * then do TX if possble'.
1999 	     */
2000 	    (iir & IIR_IMASK) != IIR_TXRDY);
2001 
2002 	/*
2003 	 * Read LSR again, since there may be an interrupt between
2004 	 * the last LSR read and IIR read above.
2005 	 */
2006 	lsr = CSR_READ_1(regsp, COM_REG_LSR);
2007 
2008 	/*
2009 	 * See if data can be transmitted as well.
2010 	 * Schedule tx done event if no data left
2011 	 * and tty was marked busy.
2012 	 */
2013 	if (ISSET(lsr, LSR_TXRDY)) {
2014 		/*
2015 		 * If we've delayed a parameter change, do it now, and restart
2016 		 * output.
2017 		 */
2018 		if (sc->sc_heldchange) {
2019 			com_loadchannelregs(sc);
2020 			sc->sc_heldchange = 0;
2021 			sc->sc_tbc = sc->sc_heldtbc;
2022 			sc->sc_heldtbc = 0;
2023 		}
2024 
2025 		/* Output the next chunk of the contiguous buffer, if any. */
2026 		if (sc->sc_tbc > 0) {
2027 			u_int n;
2028 
2029 			n = sc->sc_tbc;
2030 			if (n > sc->sc_fifolen)
2031 				n = sc->sc_fifolen;
2032 			CSR_WRITE_MULTI(regsp, COM_REG_TXDATA, sc->sc_tba, n);
2033 			sc->sc_tbc -= n;
2034 			sc->sc_tba += n;
2035 		} else {
2036 			/* Disable transmit completion interrupts if necessary. */
2037 			if (ISSET(sc->sc_ier, IER_ETXRDY)) {
2038 				CLR(sc->sc_ier, IER_ETXRDY);
2039 				CSR_WRITE_1(regsp, COM_REG_IER, sc->sc_ier);
2040 			}
2041 			if (sc->sc_tx_busy) {
2042 				sc->sc_tx_busy = 0;
2043 				sc->sc_tx_done = 1;
2044 			}
2045 		}
2046 	}
2047 
2048 	if (!ISSET((iir = CSR_READ_1(regsp, COM_REG_IIR)), IIR_NOPEND))
2049 		goto again;
2050 
2051 	mutex_spin_exit(&sc->sc_lock);
2052 
2053 	/* Wake up the poller. */
2054 	softint_schedule(sc->sc_si);
2055 
2056 #if NRND > 0 && defined(RND_COM)
2057 	rnd_add_uint32(&sc->rnd_source, iir | lsr);
2058 #endif
2059 
2060 	return (1);
2061 }
2062 
2063 /*
2064  * The following functions are polled getc and putc routines, shared
2065  * by the console and kgdb glue.
2066  *
2067  * The read-ahead code is so that you can detect pending in-band
2068  * cn_magic in polled mode while doing output rather than having to
2069  * wait until the kernel decides it needs input.
2070  */
2071 
2072 #define MAX_READAHEAD	20
2073 static int com_readahead[MAX_READAHEAD];
2074 static int com_readaheadcount = 0;
2075 
2076 int
2077 com_common_getc(dev_t dev, struct com_regs *regsp)
2078 {
2079 	int s = splserial();
2080 	u_char stat, c;
2081 
2082 	/* got a character from reading things earlier */
2083 	if (com_readaheadcount > 0) {
2084 		int i;
2085 
2086 		c = com_readahead[0];
2087 		for (i = 1; i < com_readaheadcount; i++) {
2088 			com_readahead[i-1] = com_readahead[i];
2089 		}
2090 		com_readaheadcount--;
2091 		splx(s);
2092 		return (c);
2093 	}
2094 
2095 	/* block until a character becomes available */
2096 	while (!ISSET(stat = CSR_READ_1(regsp, COM_REG_LSR), LSR_RXRDY))
2097 		;
2098 
2099 	c = CSR_READ_1(regsp, COM_REG_RXDATA);
2100 	stat = CSR_READ_1(regsp, COM_REG_IIR);
2101 	{
2102 		int cn_trapped = 0; /* unused */
2103 #ifdef DDB
2104 		extern int db_active;
2105 		if (!db_active)
2106 #endif
2107 			cn_check_magic(dev, c, com_cnm_state);
2108 	}
2109 	splx(s);
2110 	return (c);
2111 }
2112 
2113 void
2114 com_common_putc(dev_t dev, struct com_regs *regsp, int c)
2115 {
2116 	int s = splserial();
2117 	int cin, stat, timo;
2118 
2119 	if (com_readaheadcount < MAX_READAHEAD
2120 	     && ISSET(stat = CSR_READ_1(regsp, COM_REG_LSR), LSR_RXRDY)) {
2121 		int cn_trapped = 0;
2122 		cin = CSR_READ_1(regsp, COM_REG_RXDATA);
2123 		stat = CSR_READ_1(regsp, COM_REG_IIR);
2124 		cn_check_magic(dev, cin, com_cnm_state);
2125 		com_readahead[com_readaheadcount++] = cin;
2126 	}
2127 
2128 	/* wait for any pending transmission to finish */
2129 	timo = 150000;
2130 	while (!ISSET(CSR_READ_1(regsp, COM_REG_LSR), LSR_TXRDY) && --timo)
2131 		continue;
2132 
2133 	CSR_WRITE_1(regsp, COM_REG_TXDATA, c);
2134 	COM_BARRIER(regsp, BR | BW);
2135 
2136 	splx(s);
2137 }
2138 
2139 /*
2140  * Initialize UART for use as console or KGDB line.
2141  */
2142 int
2143 cominit(struct com_regs *regsp, int rate, int frequency, int type,
2144     tcflag_t cflag)
2145 {
2146 
2147 	if (bus_space_map(regsp->cr_iot, regsp->cr_iobase, regsp->cr_nports, 0,
2148 		&regsp->cr_ioh))
2149 		return (ENOMEM); /* ??? */
2150 
2151 	if (type == COM_TYPE_OMAP) {
2152 		/* disable before changing settings */
2153 		CSR_WRITE_1(regsp, COM_REG_MDR1, MDR1_MODE_DISABLE);
2154 	}
2155 
2156 	rate = comspeed(rate, frequency, type);
2157 	if (type != COM_TYPE_AU1x00) {
2158 		/* no EFR on alchemy */
2159 		CSR_WRITE_1(regsp, COM_REG_LCR, LCR_EERS);
2160 		CSR_WRITE_1(regsp, COM_REG_EFR, 0);
2161 		CSR_WRITE_1(regsp, COM_REG_LCR, LCR_DLAB);
2162 		CSR_WRITE_1(regsp, COM_REG_DLBL, rate & 0xff);
2163 		CSR_WRITE_1(regsp, COM_REG_DLBH, rate >> 8);
2164 	} else {
2165 		CSR_WRITE_1(regsp, COM_REG_DLBL, rate);
2166 	}
2167 	CSR_WRITE_1(regsp, COM_REG_LCR, cflag2lcr(cflag));
2168 	CSR_WRITE_1(regsp, COM_REG_MCR, MCR_DTR | MCR_RTS);
2169 	CSR_WRITE_1(regsp, COM_REG_FIFO,
2170 	    FIFO_ENABLE | FIFO_RCV_RST | FIFO_XMT_RST | FIFO_TRIGGER_1);
2171 
2172 	if (type == COM_TYPE_OMAP) {
2173 		/* setup the fifos.  the FCR value is not used as long
2174 		   as SCR[6] and SCR[7] are 0, which they are at reset
2175 		   and we never touch the SCR register */
2176 		uint8_t rx_fifo_trig = 40;
2177 		uint8_t tx_fifo_trig = 60;
2178 		uint8_t rx_start = 8;
2179 		uint8_t rx_halt = 60;
2180 		uint8_t tlr_value = ((rx_fifo_trig>>2) << 4) | (tx_fifo_trig>>2);
2181 		uint8_t tcr_value = ((rx_start>>2) << 4) | (rx_halt>>2);
2182 
2183 		/* enable access to TCR & TLR */
2184 		CSR_WRITE_1(regsp, COM_REG_MCR, MCR_DTR | MCR_RTS | MCR_TCR_TLR);
2185 
2186 		/* write tcr and tlr values */
2187 		CSR_WRITE_1(regsp, COM_REG_TLR, tlr_value);
2188 		CSR_WRITE_1(regsp, COM_REG_TCR, tcr_value);
2189 
2190 		/* disable access to TCR & TLR */
2191 		CSR_WRITE_1(regsp, COM_REG_MCR, MCR_DTR | MCR_RTS);
2192 
2193 		/* enable again, but mode is based on speed */
2194 		if (rate > 230400) {
2195 			CSR_WRITE_1(regsp, COM_REG_MDR1, MDR1_MODE_UART_13X);
2196 		} else {
2197 			CSR_WRITE_1(regsp, COM_REG_MDR1, MDR1_MODE_UART_16X);
2198 		}
2199 	}
2200 
2201 #ifdef COM_PXA2X0
2202 	if (type == COM_TYPE_PXA2x0)
2203 		CSR_WRITE_1(regsp, COM_REG_IER, IER_EUART);
2204 	else
2205 #endif
2206 		CSR_WRITE_1(regsp, COM_REG_IER, 0);
2207 
2208 	return (0);
2209 }
2210 
2211 /*
2212  * Following are all routines needed for COM to act as console
2213  */
2214 struct consdev comcons = {
2215 	NULL, NULL, comcngetc, comcnputc, comcnpollc, NULL, NULL, NULL,
2216 	NODEV, CN_NORMAL
2217 };
2218 
2219 
2220 int
2221 comcnattach1(struct com_regs *regsp, int rate, int frequency, int type,
2222     tcflag_t cflag)
2223 {
2224 	int res;
2225 
2226 	comconsregs = *regsp;
2227 
2228 	res = cominit(&comconsregs, rate, frequency, type, cflag);
2229 	if (res)
2230 		return (res);
2231 
2232 	cn_tab = &comcons;
2233 	cn_init_magic(&com_cnm_state);
2234 	cn_set_magic("\047\001"); /* default magic is BREAK */
2235 
2236 	comconsrate = rate;
2237 	comconscflag = cflag;
2238 
2239 	return (0);
2240 }
2241 
2242 int
2243 comcnattach(bus_space_tag_t iot, bus_addr_t iobase, int rate, int frequency,
2244     int type, tcflag_t cflag)
2245 {
2246 	struct com_regs	regs;
2247 
2248 	memset(&regs, 0, sizeof regs);
2249 	regs.cr_iot = iot;
2250 	regs.cr_iobase = iobase;
2251 	regs.cr_nports = COM_NPORTS;
2252 #ifdef	COM_REGMAP
2253 	memcpy(regs.cr_map, com_std_map, sizeof (regs.cr_map));
2254 #endif
2255 
2256 	return comcnattach1(&regs, rate, frequency, type, cflag);
2257 }
2258 
2259 int
2260 comcngetc(dev_t dev)
2261 {
2262 
2263 	return (com_common_getc(dev, &comconsregs));
2264 }
2265 
2266 /*
2267  * Console kernel output character routine.
2268  */
2269 void
2270 comcnputc(dev_t dev, int c)
2271 {
2272 
2273 	com_common_putc(dev, &comconsregs, c);
2274 }
2275 
2276 void
2277 comcnpollc(dev_t dev, int on)
2278 {
2279 
2280 }
2281 
2282 #ifdef KGDB
2283 int
2284 com_kgdb_attach1(struct com_regs *regsp, int rate, int frequency, int type,
2285     tcflag_t cflag)
2286 {
2287 	int res;
2288 
2289 	if (regsp->cr_iot == comconsregs.cr_iot &&
2290 	    regsp->cr_iobase == comconsregs.cr_iobase) {
2291 #if !defined(DDB)
2292 		return (EBUSY); /* cannot share with console */
2293 #else
2294 		comkgdbregs = *regsp;
2295 		comkgdbregs.cr_ioh = comconsregs.cr_ioh;
2296 #endif
2297 	} else {
2298 		comkgdbregs = *regsp;
2299 		res = cominit(&comkgdbregs, rate, frequency, type, cflag);
2300 		if (res)
2301 			return (res);
2302 
2303 		/*
2304 		 * XXXfvdl this shouldn't be needed, but the cn_magic goo
2305 		 * expects this to be initialized
2306 		 */
2307 		cn_init_magic(&com_cnm_state);
2308 		cn_set_magic("\047\001");
2309 	}
2310 
2311 	kgdb_attach(com_kgdb_getc, com_kgdb_putc, NULL);
2312 	kgdb_dev = 123; /* unneeded, only to satisfy some tests */
2313 
2314 	return (0);
2315 }
2316 
2317 int
2318 com_kgdb_attach(bus_space_tag_t iot, bus_addr_t iobase, int rate,
2319     int frequency, int type, tcflag_t cflag)
2320 {
2321 	struct com_regs regs;
2322 
2323 	regs.cr_iot = iot;
2324 	regs.cr_nports = COM_NPORTS;
2325 	regs.cr_iobase = iobase;
2326 #ifdef COM_REGMAP
2327 	memcpy(regs.cr_map, com_std_map, sizeof (regs.cr_map));
2328 #endif
2329 
2330 	return com_kgdb_attach1(&regs, rate, frequency, type, cflag);
2331 }
2332 
2333 /* ARGSUSED */
2334 int
2335 com_kgdb_getc(void *arg)
2336 {
2337 
2338 	return (com_common_getc(NODEV, &comkgdbregs));
2339 }
2340 
2341 /* ARGSUSED */
2342 void
2343 com_kgdb_putc(void *arg, int c)
2344 {
2345 
2346 	com_common_putc(NODEV, &comkgdbregs, c);
2347 }
2348 #endif /* KGDB */
2349 
2350 /* helper function to identify the com ports used by
2351  console or KGDB (and not yet autoconf attached) */
2352 int
2353 com_is_console(bus_space_tag_t iot, bus_addr_t iobase, bus_space_handle_t *ioh)
2354 {
2355 	bus_space_handle_t help;
2356 
2357 	if (!comconsattached &&
2358 	    iot == comconsregs.cr_iot && iobase == comconsregs.cr_iobase)
2359 		help = comconsregs.cr_ioh;
2360 #ifdef KGDB
2361 	else if (!com_kgdb_attached &&
2362 	    iot == comkgdbregs.cr_iot && iobase == comkgdbregs.cr_iobase)
2363 		help = comkgdbregs.cr_ioh;
2364 #endif
2365 	else
2366 		return (0);
2367 
2368 	if (ioh)
2369 		*ioh = help;
2370 	return (1);
2371 }
2372 
2373 /*
2374  * this routine exists to serve as a shutdown hook for systems that
2375  * have firmware which doesn't interact properly with a com device in
2376  * FIFO mode.
2377  */
2378 bool
2379 com_cleanup(device_t self, int how)
2380 {
2381 	struct com_softc *sc = device_private(self);
2382 
2383 	if (ISSET(sc->sc_hwflags, COM_HW_FIFO))
2384 		CSR_WRITE_1(&sc->sc_regs, COM_REG_FIFO, 0);
2385 
2386 	return true;
2387 }
2388 
2389 bool
2390 com_suspend(device_t self PMF_FN_ARGS)
2391 {
2392 	struct com_softc *sc = device_private(self);
2393 
2394 	CSR_WRITE_1(&sc->sc_regs, COM_REG_IER, 0);
2395 	(void)CSR_READ_1(&sc->sc_regs, COM_REG_IIR);
2396 
2397 	return true;
2398 }
2399 
2400 bool
2401 com_resume(device_t self PMF_FN_ARGS)
2402 {
2403 	struct com_softc *sc = device_private(self);
2404 
2405 	mutex_spin_enter(&sc->sc_lock);
2406 	com_loadchannelregs(sc);
2407 	mutex_spin_exit(&sc->sc_lock);
2408 
2409 	return true;
2410 }
2411