xref: /netbsd-src/sys/dev/ic/com.c (revision b1c86f5f087524e68db12794ee9c3e3da1ab17a0)
1 /* $NetBSD: com.c,v 1.298 2010/07/20 06:17:20 jklos 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, "$NetBSD: com.c,v 1.298 2010/07/20 06:17:20 jklos 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/conf.h>
108 #include <sys/file.h>
109 #include <sys/uio.h>
110 #include <sys/kernel.h>
111 #include <sys/syslog.h>
112 #include <sys/device.h>
113 #include <sys/malloc.h>
114 #include <sys/timepps.h>
115 #include <sys/vnode.h>
116 #include <sys/kauth.h>
117 #include <sys/intr.h>
118 
119 #include <sys/bus.h>
120 
121 #include <dev/ic/comreg.h>
122 #include <dev/ic/comvar.h>
123 #include <dev/ic/ns16550reg.h>
124 #include <dev/ic/st16650reg.h>
125 #ifdef COM_HAYESP
126 #include <dev/ic/hayespreg.h>
127 #endif
128 #define	com_lcr	com_cfcr
129 #include <dev/cons.h>
130 
131 #ifdef	COM_REGMAP
132 #define	CSR_WRITE_1(r, o, v)	\
133 	bus_space_write_1((r)->cr_iot, (r)->cr_ioh, (r)->cr_map[o], v)
134 #define	CSR_READ_1(r, o)	\
135 	bus_space_read_1((r)->cr_iot, (r)->cr_ioh, (r)->cr_map[o])
136 #define	CSR_WRITE_2(r, o, v)	\
137 	bus_space_write_2((r)->cr_iot, (r)->cr_ioh, (r)->cr_map[o], v)
138 #define	CSR_READ_2(r, o)	\
139 	bus_space_read_2((r)->cr_iot, (r)->cr_ioh, (r)->cr_map[o])
140 #define	CSR_WRITE_MULTI(r, o, p, n)	\
141 	bus_space_write_multi_1((r)->cr_iot, (r)->cr_ioh, (r)->cr_map[o], p, n)
142 #else
143 #define	CSR_WRITE_1(r, o, v)	\
144 	bus_space_write_1((r)->cr_iot, (r)->cr_ioh, o, v)
145 #define	CSR_READ_1(r, o)	\
146 	bus_space_read_1((r)->cr_iot, (r)->cr_ioh, o)
147 #define	CSR_WRITE_2(r, o, v)	\
148 	bus_space_write_2((r)->cr_iot, (r)->cr_ioh, o, v)
149 #define	CSR_READ_2(r, o)	\
150 	bus_space_read_2((r)->cr_iot, (r)->cr_ioh, o)
151 #define	CSR_WRITE_MULTI(r, o, p, n)	\
152 	bus_space_write_multi_1((r)->cr_iot, (r)->cr_ioh, o, p, n)
153 #endif
154 
155 
156 static void com_enable_debugport(struct com_softc *);
157 
158 void	com_config(struct com_softc *);
159 void	com_shutdown(struct com_softc *);
160 int	comspeed(long, long, int);
161 static	u_char	cflag2lcr(tcflag_t);
162 int	comparam(struct tty *, struct termios *);
163 void	comstart(struct tty *);
164 int	comhwiflow(struct tty *, int);
165 
166 void	com_loadchannelregs(struct com_softc *);
167 void	com_hwiflow(struct com_softc *);
168 void	com_break(struct com_softc *, int);
169 void	com_modem(struct com_softc *, int);
170 void	tiocm_to_com(struct com_softc *, u_long, int);
171 int	com_to_tiocm(struct com_softc *);
172 void	com_iflush(struct com_softc *);
173 
174 int	com_common_getc(dev_t, struct com_regs *);
175 static void	com_common_putc(dev_t, struct com_regs *, int);
176 
177 int	cominit(struct com_regs *, int, int, int, tcflag_t);
178 
179 static int comcnreattach(void);
180 
181 int	comcngetc(dev_t);
182 void	comcnputc(dev_t, int);
183 void	comcnpollc(dev_t, int);
184 
185 #define	integrate	static inline
186 void 	comsoft(void *);
187 integrate void com_rxsoft(struct com_softc *, struct tty *);
188 integrate void com_txsoft(struct com_softc *, struct tty *);
189 integrate void com_stsoft(struct com_softc *, struct tty *);
190 integrate void com_schedrx(struct com_softc *);
191 void	comdiag(void *);
192 
193 extern struct cfdriver com_cd;
194 
195 dev_type_open(comopen);
196 dev_type_close(comclose);
197 dev_type_read(comread);
198 dev_type_write(comwrite);
199 dev_type_ioctl(comioctl);
200 dev_type_stop(comstop);
201 dev_type_tty(comtty);
202 dev_type_poll(compoll);
203 
204 static struct comcons_info comcons_info;
205 
206 /*
207  * Following are all routines needed for COM to act as console
208  */
209 static struct consdev comcons = {
210 	NULL, NULL, comcngetc, comcnputc, comcnpollc, NULL, NULL, NULL,
211 	NODEV, CN_NORMAL
212 };
213 
214 
215 const struct cdevsw com_cdevsw = {
216 	comopen, comclose, comread, comwrite, comioctl,
217 	comstop, comtty, compoll, nommap, ttykqfilter, D_TTY
218 };
219 
220 /*
221  * Make this an option variable one can patch.
222  * But be warned:  this must be a power of 2!
223  */
224 u_int com_rbuf_size = COM_RING_SIZE;
225 
226 /* Stop input when 3/4 of the ring is full; restart when only 1/4 is full. */
227 u_int com_rbuf_hiwat = (COM_RING_SIZE * 1) / 4;
228 u_int com_rbuf_lowat = (COM_RING_SIZE * 3) / 4;
229 
230 static int comconsattached;
231 static struct cnm_state com_cnm_state;
232 
233 #ifdef KGDB
234 #include <sys/kgdb.h>
235 
236 static struct com_regs comkgdbregs;
237 static int com_kgdb_attached;
238 
239 int	com_kgdb_getc(void *);
240 void	com_kgdb_putc(void *, int);
241 #endif /* KGDB */
242 
243 #ifdef COM_REGMAP
244 /* initializer for typical 16550-ish hardware */
245 #define	COM_REG_16550	{ \
246 	com_data, com_data, com_dlbl, com_dlbh, com_ier, com_iir, com_fifo, \
247 	com_efr, com_lcr, com_mcr, com_lsr, com_msr }
248 
249 const bus_size_t com_std_map[16] = COM_REG_16550;
250 #endif /* COM_REGMAP */
251 
252 #define	COMUNIT_MASK	0x7ffff
253 #define	COMDIALOUT_MASK	0x80000
254 
255 #define	COMUNIT(x)	(minor(x) & COMUNIT_MASK)
256 #define	COMDIALOUT(x)	(minor(x) & COMDIALOUT_MASK)
257 
258 #define	COM_ISALIVE(sc)	((sc)->enabled != 0 && \
259 			 device_is_active((sc)->sc_dev))
260 
261 #define	BR	BUS_SPACE_BARRIER_READ
262 #define	BW	BUS_SPACE_BARRIER_WRITE
263 #define COM_BARRIER(r, f) \
264 	bus_space_barrier((r)->cr_iot, (r)->cr_ioh, 0, (r)->cr_nports, (f))
265 
266 /*ARGSUSED*/
267 int
268 comspeed(long speed, long frequency, int type)
269 {
270 #define	divrnd(n, q)	(((n)*2/(q)+1)/2)	/* divide and round off */
271 
272 	int x, err;
273 	int divisor = 16;
274 
275 	if ((type == COM_TYPE_OMAP) && (speed > 230400)) {
276 	    divisor = 13;
277 	}
278 
279 #if 0
280 	if (speed == 0)
281 		return (0);
282 #endif
283 	if (speed <= 0)
284 		return (-1);
285 	x = divrnd(frequency / divisor, speed);
286 	if (x <= 0)
287 		return (-1);
288 	err = divrnd(((quad_t)frequency) * 1000 / divisor, speed * x) - 1000;
289 	if (err < 0)
290 		err = -err;
291 	if (err > COM_TOLERANCE)
292 		return (-1);
293 	return (x);
294 
295 #undef	divrnd
296 }
297 
298 #ifdef COM_DEBUG
299 int	com_debug = 0;
300 
301 void comstatus(struct com_softc *, const char *);
302 void
303 comstatus(struct com_softc *sc, const char *str)
304 {
305 	struct tty *tp = sc->sc_tty;
306 
307 	aprint_normal_dev(sc->sc_dev,
308 	    "%s %cclocal  %cdcd %cts_carr_on %cdtr %ctx_stopped\n",
309 	    str,
310 	    ISSET(tp->t_cflag, CLOCAL) ? '+' : '-',
311 	    ISSET(sc->sc_msr, MSR_DCD) ? '+' : '-',
312 	    ISSET(tp->t_state, TS_CARR_ON) ? '+' : '-',
313 	    ISSET(sc->sc_mcr, MCR_DTR) ? '+' : '-',
314 	    sc->sc_tx_stopped ? '+' : '-');
315 
316 	aprint_normal_dev(sc->sc_dev,
317 	    "%s %ccrtscts %ccts %cts_ttstop  %crts rx_flags=0x%x\n",
318 	    str,
319 	    ISSET(tp->t_cflag, CRTSCTS) ? '+' : '-',
320 	    ISSET(sc->sc_msr, MSR_CTS) ? '+' : '-',
321 	    ISSET(tp->t_state, TS_TTSTOP) ? '+' : '-',
322 	    ISSET(sc->sc_mcr, MCR_RTS) ? '+' : '-',
323 	    sc->sc_rx_flags);
324 }
325 #endif
326 
327 int
328 com_probe_subr(struct com_regs *regs)
329 {
330 
331 	/* force access to id reg */
332 	CSR_WRITE_1(regs, COM_REG_LCR, LCR_8BITS);
333 	CSR_WRITE_1(regs, COM_REG_IIR, 0);
334 	if ((CSR_READ_1(regs, COM_REG_LCR) != LCR_8BITS) ||
335 	    (CSR_READ_1(regs, COM_REG_IIR) & 0x38))
336 		return (0);
337 
338 	return (1);
339 }
340 
341 int
342 comprobe1(bus_space_tag_t iot, bus_space_handle_t ioh)
343 {
344 	struct com_regs	regs;
345 
346 	regs.cr_iot = iot;
347 	regs.cr_ioh = ioh;
348 #ifdef	COM_REGMAP
349 	memcpy(regs.cr_map, com_std_map, sizeof (regs.cr_map));
350 #endif
351 
352 	return com_probe_subr(&regs);
353 }
354 
355 /*
356  * No locking in this routine; it is only called during attach,
357  * or with the port already locked.
358  */
359 static void
360 com_enable_debugport(struct com_softc *sc)
361 {
362 
363 	/* Turn on line break interrupt, set carrier. */
364 	sc->sc_ier = IER_ERXRDY;
365 	if (sc->sc_type == COM_TYPE_PXA2x0)
366 		sc->sc_ier |= IER_EUART | IER_ERXTOUT;
367 	CSR_WRITE_1(&sc->sc_regs, COM_REG_IER, sc->sc_ier);
368 	SET(sc->sc_mcr, MCR_DTR | MCR_RTS);
369 	CSR_WRITE_1(&sc->sc_regs, COM_REG_MCR, sc->sc_mcr);
370 }
371 
372 void
373 com_attach_subr(struct com_softc *sc)
374 {
375 	struct com_regs *regsp = &sc->sc_regs;
376 	struct tty *tp;
377 #ifdef COM_16650
378 	u_int8_t lcr;
379 #endif
380 	const char *fifo_msg = NULL;
381 
382 	aprint_naive("\n");
383 
384 	callout_init(&sc->sc_diag_callout, 0);
385 	mutex_init(&sc->sc_lock, MUTEX_DEFAULT, IPL_HIGH);
386 
387 	/* Disable interrupts before configuring the device. */
388 	if (sc->sc_type == COM_TYPE_PXA2x0)
389 		sc->sc_ier = IER_EUART;
390 	else
391 		sc->sc_ier = 0;
392 
393 	CSR_WRITE_1(regsp, COM_REG_IER, sc->sc_ier);
394 
395 	if (bus_space_is_equal(regsp->cr_iot, comcons_info.regs.cr_iot) &&
396 	    regsp->cr_iobase == comcons_info.regs.cr_iobase) {
397 		comconsattached = 1;
398 
399 		if (cn_tab == NULL && comcnreattach() != 0) {
400 			printf("can't re-init serial console @%lx\n",
401 			    (u_long)comcons_info.regs.cr_iobase);
402 		}
403 
404 		/* Make sure the console is always "hardwired". */
405 		delay(10000);			/* wait for output to finish */
406 		SET(sc->sc_hwflags, COM_HW_CONSOLE);
407 		SET(sc->sc_swflags, TIOCFLAG_SOFTCAR);
408 	}
409 
410 	/* Probe for FIFO */
411 	switch (sc->sc_type) {
412 	case COM_TYPE_HAYESP:
413 		goto fifodone;
414 
415 	case COM_TYPE_AU1x00:
416 		sc->sc_fifolen = 16;
417 		fifo_msg = "Au1X00 UART, working fifo";
418 		SET(sc->sc_hwflags, COM_HW_FIFO);
419 		goto fifodelay;
420 
421 	case COM_TYPE_16550_NOERS:
422 		sc->sc_fifolen = 16;
423 		fifo_msg = "ns16650, no ERS, working fifo";
424 		SET(sc->sc_hwflags, COM_HW_FIFO);
425 		goto fifodelay;
426 
427  	case COM_TYPE_OMAP:
428  		sc->sc_fifolen = 64;
429  		fifo_msg = "OMAP UART, working fifo";
430  		SET(sc->sc_hwflags, COM_HW_FIFO);
431  		goto fifodelay;
432   	}
433 
434 	sc->sc_fifolen = 1;
435 	/* look for a NS 16550AF UART with FIFOs */
436 	CSR_WRITE_1(regsp, COM_REG_FIFO,
437 	    FIFO_ENABLE | FIFO_RCV_RST | FIFO_XMT_RST | FIFO_TRIGGER_14);
438 	delay(100);
439 	if (ISSET(CSR_READ_1(regsp, COM_REG_IIR), IIR_FIFO_MASK)
440 	    == IIR_FIFO_MASK)
441 		if (ISSET(CSR_READ_1(regsp, COM_REG_FIFO), FIFO_TRIGGER_14)
442 		    == FIFO_TRIGGER_14) {
443 			SET(sc->sc_hwflags, COM_HW_FIFO);
444 
445 #ifdef COM_16650
446 			/*
447 			 * IIR changes into the EFR if LCR is set to LCR_EERS
448 			 * on 16650s. We also know IIR != 0 at this point.
449 			 * Write 0 into the EFR, and read it. If the result
450 			 * is 0, we have a 16650.
451 			 *
452 			 * Older 16650s were broken; the test to detect them
453 			 * is taken from the Linux driver. Apparently
454 			 * setting DLAB enable gives access to the EFR on
455 			 * these chips.
456 			 */
457 			lcr = CSR_READ_1(regsp, COM_REG_LCR);
458 			CSR_WRITE_1(regsp, COM_REG_LCR, LCR_EERS);
459 			CSR_WRITE_1(regsp, COM_REG_EFR, 0);
460 			if (CSR_READ_1(regsp, COM_REG_EFR) == 0) {
461 				CSR_WRITE_1(regsp, COM_REG_LCR,
462 				    lcr | LCR_DLAB);
463 				if (CSR_READ_1(regsp, COM_REG_EFR) == 0) {
464 					CLR(sc->sc_hwflags, COM_HW_FIFO);
465 					sc->sc_fifolen = 0;
466 				} else {
467 					SET(sc->sc_hwflags, COM_HW_FLOW);
468 					SET(sc->sc_mcr, MCR_PRESCALE);
469 					sc->sc_frequency /= 4;
470 					sc->sc_fifolen = 32;
471 				}
472 			} else
473 #endif
474 				sc->sc_fifolen = 16;
475 
476 #ifdef COM_16650
477 			CSR_WRITE_1(regsp, COM_REG_LCR, lcr);
478 			if (sc->sc_fifolen == 0)
479 				fifo_msg = "st16650, broken fifo";
480 			else if (sc->sc_fifolen == 32)
481 				fifo_msg = "st16650a, working fifo";
482 			else
483 #endif
484 				fifo_msg = "ns16550a, working fifo";
485 		} else
486 			fifo_msg = "ns16550, broken fifo";
487 	else
488 		fifo_msg = "ns8250 or ns16450, no fifo";
489 	CSR_WRITE_1(regsp, COM_REG_FIFO, 0);
490 fifodelay:
491 	/*
492 	 * Some chips will clear down both Tx and Rx FIFOs when zero is
493 	 * written to com_fifo. If this chip is the console, writing zero
494 	 * results in some of the chip/FIFO description being lost, so delay
495 	 * printing it until now.
496 	 */
497 	delay(10);
498 	aprint_normal(": %s\n", fifo_msg);
499 	if (ISSET(sc->sc_hwflags, COM_HW_TXFIFO_DISABLE)) {
500 		sc->sc_fifolen = 1;
501 		aprint_normal_dev(sc->sc_dev, "txfifo disabled\n");
502 	}
503 
504 fifodone:
505 
506 	tp = ttymalloc();
507 	tp->t_oproc = comstart;
508 	tp->t_param = comparam;
509 	tp->t_hwiflow = comhwiflow;
510 
511 	sc->sc_tty = tp;
512 	sc->sc_rbuf = malloc(com_rbuf_size << 1, M_DEVBUF, M_NOWAIT);
513 	sc->sc_rbput = sc->sc_rbget = sc->sc_rbuf;
514 	sc->sc_rbavail = com_rbuf_size;
515 	if (sc->sc_rbuf == NULL) {
516 		aprint_error_dev(sc->sc_dev,
517 		    "unable to allocate ring buffer\n");
518 		return;
519 	}
520 	sc->sc_ebuf = sc->sc_rbuf + (com_rbuf_size << 1);
521 
522 	tty_attach(tp);
523 
524 	if (!ISSET(sc->sc_hwflags, COM_HW_NOIEN))
525 		SET(sc->sc_mcr, MCR_IENABLE);
526 
527 	if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
528 		int maj;
529 
530 		/* locate the major number */
531 		maj = cdevsw_lookup_major(&com_cdevsw);
532 
533 		tp->t_dev = cn_tab->cn_dev = makedev(maj,
534 						     device_unit(sc->sc_dev));
535 
536 		aprint_normal_dev(sc->sc_dev, "console\n");
537 	}
538 
539 #ifdef KGDB
540 	/*
541 	 * Allow kgdb to "take over" this port.  If this is
542 	 * not the console and is the kgdb device, it has
543 	 * exclusive use.  If it's the console _and_ the
544 	 * kgdb device, it doesn't.
545 	 */
546 	if (bus_space_is_equal(regsp->cr_iot, comkgdbregs.cr_iot) &&
547 	    regsp->cr_iobase == comkgdbregs.cr_iobase) {
548 		if (!ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
549 			com_kgdb_attached = 1;
550 
551 			SET(sc->sc_hwflags, COM_HW_KGDB);
552 		}
553 		aprint_normal_dev(sc->sc_dev, "kgdb\n");
554 	}
555 #endif
556 
557 	sc->sc_si = softint_establish(SOFTINT_SERIAL, comsoft, sc);
558 
559 #if NRND > 0 && defined(RND_COM)
560 	rnd_attach_source(&sc->rnd_source, device_xname(sc->sc_dev),
561 			  RND_TYPE_TTY, 0);
562 #endif
563 
564 	/* if there are no enable/disable functions, assume the device
565 	   is always enabled */
566 	if (!sc->enable)
567 		sc->enabled = 1;
568 
569 	com_config(sc);
570 
571 	SET(sc->sc_hwflags, COM_HW_DEV_OK);
572 }
573 
574 void
575 com_config(struct com_softc *sc)
576 {
577 	struct com_regs *regsp = &sc->sc_regs;
578 
579 	/* Disable interrupts before configuring the device. */
580 	if (sc->sc_type == COM_TYPE_PXA2x0)
581 		sc->sc_ier = IER_EUART;
582 	else
583 		sc->sc_ier = 0;
584 	CSR_WRITE_1(regsp, COM_REG_IER, sc->sc_ier);
585 	(void) CSR_READ_1(regsp, COM_REG_IIR);
586 
587 #ifdef COM_HAYESP
588 	/* Look for a Hayes ESP board. */
589 	if (sc->sc_type == COM_TYPE_HAYESP) {
590 
591 		/* Set 16550 compatibility mode */
592 		bus_space_write_1(regsp->cr_iot, sc->sc_hayespioh, HAYESP_CMD1,
593 				  HAYESP_SETMODE);
594 		bus_space_write_1(regsp->cr_iot, sc->sc_hayespioh, HAYESP_CMD2,
595 				  HAYESP_MODE_FIFO|HAYESP_MODE_RTS|
596 				  HAYESP_MODE_SCALE);
597 
598 		/* Set RTS/CTS flow control */
599 		bus_space_write_1(regsp->cr_iot, sc->sc_hayespioh, HAYESP_CMD1,
600 				  HAYESP_SETFLOWTYPE);
601 		bus_space_write_1(regsp->cr_iot, sc->sc_hayespioh, HAYESP_CMD2,
602 				  HAYESP_FLOW_RTS);
603 		bus_space_write_1(regsp->cr_iot, sc->sc_hayespioh, HAYESP_CMD2,
604 				  HAYESP_FLOW_CTS);
605 
606 		/* Set flow control levels */
607 		bus_space_write_1(regsp->cr_iot, sc->sc_hayespioh, HAYESP_CMD1,
608 				  HAYESP_SETRXFLOW);
609 		bus_space_write_1(regsp->cr_iot, sc->sc_hayespioh, HAYESP_CMD2,
610 				  HAYESP_HIBYTE(HAYESP_RXHIWMARK));
611 		bus_space_write_1(regsp->cr_iot, sc->sc_hayespioh, HAYESP_CMD2,
612 				  HAYESP_LOBYTE(HAYESP_RXHIWMARK));
613 		bus_space_write_1(regsp->cr_iot, sc->sc_hayespioh, HAYESP_CMD2,
614 				  HAYESP_HIBYTE(HAYESP_RXLOWMARK));
615 		bus_space_write_1(regsp->cr_iot, sc->sc_hayespioh, HAYESP_CMD2,
616 				  HAYESP_LOBYTE(HAYESP_RXLOWMARK));
617 	}
618 #endif
619 
620 	if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE|COM_HW_KGDB))
621 		com_enable_debugport(sc);
622 }
623 
624 #if 0
625 static int
626 comcngetc_detached(dev_t dev)
627 {
628 	return 0;
629 }
630 
631 static void
632 comcnputc_detached(dev_t dev, int c)
633 {
634 }
635 #endif
636 
637 int
638 com_detach(device_t self, int flags)
639 {
640 	struct com_softc *sc = device_private(self);
641 	int maj, mn;
642 
643 	if (ISSET(sc->sc_hwflags, COM_HW_KGDB))
644 		return EBUSY;
645 
646         if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE) &&
647 	    (flags & DETACH_SHUTDOWN) != 0)
648 		return EBUSY;
649 
650 	if (sc->disable != NULL && sc->enabled != 0) {
651 		(*sc->disable)(sc);
652 		sc->enabled = 0;
653 	}
654 
655         if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
656 		comconsattached = 0;
657 		cn_tab = NULL;
658 	}
659 
660 	/* locate the major number */
661 	maj = cdevsw_lookup_major(&com_cdevsw);
662 
663 	/* Nuke the vnodes for any open instances. */
664 	mn = device_unit(self);
665 	vdevgone(maj, mn, mn, VCHR);
666 
667 	mn |= COMDIALOUT_MASK;
668 	vdevgone(maj, mn, mn, VCHR);
669 
670 	if (sc->sc_rbuf == NULL) {
671 		/*
672 		 * Ring buffer allocation failed in the com_attach_subr,
673 		 * only the tty is allocated, and nothing else.
674 		 */
675 		ttyfree(sc->sc_tty);
676 		return 0;
677 	}
678 
679 	/* Free the receive buffer. */
680 	free(sc->sc_rbuf, M_DEVBUF);
681 
682 	/* Detach and free the tty. */
683 	tty_detach(sc->sc_tty);
684 	ttyfree(sc->sc_tty);
685 
686 	/* Unhook the soft interrupt handler. */
687 	softint_disestablish(sc->sc_si);
688 
689 #if NRND > 0 && defined(RND_COM)
690 	/* Unhook the entropy source. */
691 	rnd_detach_source(&sc->rnd_source);
692 #endif
693 	callout_destroy(&sc->sc_diag_callout);
694 
695 	/* Destroy the lock. */
696 	mutex_destroy(&sc->sc_lock);
697 
698 	return (0);
699 }
700 
701 void
702 com_shutdown(struct com_softc *sc)
703 {
704 	struct tty *tp = sc->sc_tty;
705 
706 	mutex_spin_enter(&sc->sc_lock);
707 
708 	/* If we were asserting flow control, then deassert it. */
709 	SET(sc->sc_rx_flags, RX_IBUF_BLOCKED);
710 	com_hwiflow(sc);
711 
712 	/* Clear any break condition set with TIOCSBRK. */
713 	com_break(sc, 0);
714 
715 	/*
716 	 * Hang up if necessary.  Wait a bit, so the other side has time to
717 	 * notice even if we immediately open the port again.
718 	 * Avoid tsleeping above splhigh().
719 	 */
720 	if (ISSET(tp->t_cflag, HUPCL)) {
721 		com_modem(sc, 0);
722 		mutex_spin_exit(&sc->sc_lock);
723 		/* XXX will only timeout */
724 		(void) kpause(ttclos, false, hz, NULL);
725 		mutex_spin_enter(&sc->sc_lock);
726 	}
727 
728 	/* Turn off interrupts. */
729 	if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
730 		sc->sc_ier = IER_ERXRDY; /* interrupt on break */
731 		if (sc->sc_type == COM_TYPE_PXA2x0)
732 			sc->sc_ier |= IER_ERXTOUT;
733 	} else
734 		sc->sc_ier = 0;
735 
736 	if (sc->sc_type == COM_TYPE_PXA2x0)
737 		sc->sc_ier |= IER_EUART;
738 
739 	CSR_WRITE_1(&sc->sc_regs, COM_REG_IER, sc->sc_ier);
740 
741 	mutex_spin_exit(&sc->sc_lock);
742 
743 	if (sc->disable) {
744 #ifdef DIAGNOSTIC
745 		if (!sc->enabled)
746 			panic("com_shutdown: not enabled?");
747 #endif
748 		(*sc->disable)(sc);
749 		sc->enabled = 0;
750 	}
751 }
752 
753 int
754 comopen(dev_t dev, int flag, int mode, struct lwp *l)
755 {
756 	struct com_softc *sc;
757 	struct tty *tp;
758 	int s;
759 	int error;
760 
761 	sc = device_lookup_private(&com_cd, COMUNIT(dev));
762 	if (sc == NULL || !ISSET(sc->sc_hwflags, COM_HW_DEV_OK) ||
763 		sc->sc_rbuf == NULL)
764 		return (ENXIO);
765 
766 	if (!device_is_active(sc->sc_dev))
767 		return (ENXIO);
768 
769 #ifdef KGDB
770 	/*
771 	 * If this is the kgdb port, no other use is permitted.
772 	 */
773 	if (ISSET(sc->sc_hwflags, COM_HW_KGDB))
774 		return (EBUSY);
775 #endif
776 
777 	tp = sc->sc_tty;
778 
779 	if (kauth_authorize_device_tty(l->l_cred, KAUTH_DEVICE_TTY_OPEN, tp))
780 		return (EBUSY);
781 
782 	s = spltty();
783 
784 	/*
785 	 * Do the following iff this is a first open.
786 	 */
787 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
788 		struct termios t;
789 
790 		tp->t_dev = dev;
791 
792 
793 		if (sc->enable) {
794 			if ((*sc->enable)(sc)) {
795 				splx(s);
796 				aprint_error_dev(sc->sc_dev,
797 				    "device enable failed\n");
798 				return (EIO);
799 			}
800 			mutex_spin_enter(&sc->sc_lock);
801 			sc->enabled = 1;
802 			com_config(sc);
803 		} else {
804 			mutex_spin_enter(&sc->sc_lock);
805 		}
806 
807 		/* Turn on interrupts. */
808 		sc->sc_ier = IER_ERXRDY | IER_ERLS | IER_EMSC;
809 		if (sc->sc_type == COM_TYPE_PXA2x0)
810 			sc->sc_ier |= IER_EUART | IER_ERXTOUT;
811 		CSR_WRITE_1(&sc->sc_regs, COM_REG_IER, sc->sc_ier);
812 
813 		/* Fetch the current modem control status, needed later. */
814 		sc->sc_msr = CSR_READ_1(&sc->sc_regs, COM_REG_MSR);
815 
816 		/* Clear PPS capture state on first open. */
817 		mutex_spin_enter(&timecounter_lock);
818 		memset(&sc->sc_pps_state, 0, sizeof(sc->sc_pps_state));
819 		sc->sc_pps_state.ppscap = PPS_CAPTUREASSERT | PPS_CAPTURECLEAR;
820 		pps_init(&sc->sc_pps_state);
821 		mutex_spin_exit(&timecounter_lock);
822 
823 		mutex_spin_exit(&sc->sc_lock);
824 
825 		/*
826 		 * Initialize the termios status to the defaults.  Add in the
827 		 * sticky bits from TIOCSFLAGS.
828 		 */
829 		if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
830 			t.c_ospeed = comcons_info.rate;
831 			t.c_cflag = comcons_info.cflag;
832 		} else {
833 			t.c_ospeed = TTYDEF_SPEED;
834 			t.c_cflag = TTYDEF_CFLAG;
835 		}
836 		t.c_ispeed = t.c_ospeed;
837 		if (ISSET(sc->sc_swflags, TIOCFLAG_CLOCAL))
838 			SET(t.c_cflag, CLOCAL);
839 		if (ISSET(sc->sc_swflags, TIOCFLAG_CRTSCTS))
840 			SET(t.c_cflag, CRTSCTS);
841 		if (ISSET(sc->sc_swflags, TIOCFLAG_MDMBUF))
842 			SET(t.c_cflag, MDMBUF);
843 		/* Make sure comparam() will do something. */
844 		tp->t_ospeed = 0;
845 		(void) comparam(tp, &t);
846 		tp->t_iflag = TTYDEF_IFLAG;
847 		tp->t_oflag = TTYDEF_OFLAG;
848 		tp->t_lflag = TTYDEF_LFLAG;
849 		ttychars(tp);
850 		ttsetwater(tp);
851 
852 		mutex_spin_enter(&sc->sc_lock);
853 
854 		/*
855 		 * Turn on DTR.  We must always do this, even if carrier is not
856 		 * present, because otherwise we'd have to use TIOCSDTR
857 		 * immediately after setting CLOCAL, which applications do not
858 		 * expect.  We always assert DTR while the device is open
859 		 * unless explicitly requested to deassert it.
860 		 */
861 		com_modem(sc, 1);
862 
863 		/* Clear the input ring, and unblock. */
864 		sc->sc_rbput = sc->sc_rbget = sc->sc_rbuf;
865 		sc->sc_rbavail = com_rbuf_size;
866 		com_iflush(sc);
867 		CLR(sc->sc_rx_flags, RX_ANY_BLOCK);
868 		com_hwiflow(sc);
869 
870 #ifdef COM_DEBUG
871 		if (com_debug)
872 			comstatus(sc, "comopen  ");
873 #endif
874 
875 		mutex_spin_exit(&sc->sc_lock);
876 	}
877 
878 	splx(s);
879 
880 	error = ttyopen(tp, COMDIALOUT(dev), ISSET(flag, O_NONBLOCK));
881 	if (error)
882 		goto bad;
883 
884 	error = (*tp->t_linesw->l_open)(dev, tp);
885 	if (error)
886 		goto bad;
887 
888 	return (0);
889 
890 bad:
891 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
892 		/*
893 		 * We failed to open the device, and nobody else had it opened.
894 		 * Clean up the state as appropriate.
895 		 */
896 		com_shutdown(sc);
897 	}
898 
899 	return (error);
900 }
901 
902 int
903 comclose(dev_t dev, int flag, int mode, struct lwp *l)
904 {
905 	struct com_softc *sc =
906 	    device_lookup_private(&com_cd, COMUNIT(dev));
907 	struct tty *tp = sc->sc_tty;
908 
909 	/* XXX This is for cons.c. */
910 	if (!ISSET(tp->t_state, TS_ISOPEN))
911 		return (0);
912 
913 	(*tp->t_linesw->l_close)(tp, flag);
914 	ttyclose(tp);
915 
916 	if (COM_ISALIVE(sc) == 0)
917 		return (0);
918 
919 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
920 		/*
921 		 * Although we got a last close, the device may still be in
922 		 * use; e.g. if this was the dialout node, and there are still
923 		 * processes waiting for carrier on the non-dialout node.
924 		 */
925 		com_shutdown(sc);
926 	}
927 
928 	return (0);
929 }
930 
931 int
932 comread(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_read)(tp, uio, flag));
942 }
943 
944 int
945 comwrite(dev_t dev, struct uio *uio, int flag)
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 (EIO);
953 
954 	return ((*tp->t_linesw->l_write)(tp, uio, flag));
955 }
956 
957 int
958 compoll(dev_t dev, int events, struct lwp *l)
959 {
960 	struct com_softc *sc =
961 	    device_lookup_private(&com_cd, COMUNIT(dev));
962 	struct tty *tp = sc->sc_tty;
963 
964 	if (COM_ISALIVE(sc) == 0)
965 		return (POLLHUP);
966 
967 	return ((*tp->t_linesw->l_poll)(tp, events, l));
968 }
969 
970 struct tty *
971 comtty(dev_t dev)
972 {
973 	struct com_softc *sc =
974 	    device_lookup_private(&com_cd, COMUNIT(dev));
975 	struct tty *tp = sc->sc_tty;
976 
977 	return (tp);
978 }
979 
980 int
981 comioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l)
982 {
983 	struct com_softc *sc;
984 	struct tty *tp;
985 	int error;
986 
987 	sc = device_lookup_private(&com_cd, COMUNIT(dev));
988 	if (sc == NULL)
989 		return ENXIO;
990 	if (COM_ISALIVE(sc) == 0)
991 		return (EIO);
992 
993 	tp = sc->sc_tty;
994 
995 	error = (*tp->t_linesw->l_ioctl)(tp, cmd, data, flag, l);
996 	if (error != EPASSTHROUGH)
997 		return (error);
998 
999 	error = ttioctl(tp, cmd, data, flag, l);
1000 	if (error != EPASSTHROUGH)
1001 		return (error);
1002 
1003 	error = 0;
1004 	switch (cmd) {
1005 	case TIOCSFLAGS:
1006 		error = kauth_authorize_device_tty(l->l_cred,
1007 		    KAUTH_DEVICE_TTY_PRIVSET, tp);
1008 		break;
1009 	default:
1010 		/* nothing */
1011 		break;
1012 	}
1013 	if (error) {
1014 		return error;
1015 	}
1016 
1017 	mutex_spin_enter(&sc->sc_lock);
1018 
1019 	switch (cmd) {
1020 	case TIOCSBRK:
1021 		com_break(sc, 1);
1022 		break;
1023 
1024 	case TIOCCBRK:
1025 		com_break(sc, 0);
1026 		break;
1027 
1028 	case TIOCSDTR:
1029 		com_modem(sc, 1);
1030 		break;
1031 
1032 	case TIOCCDTR:
1033 		com_modem(sc, 0);
1034 		break;
1035 
1036 	case TIOCGFLAGS:
1037 		*(int *)data = sc->sc_swflags;
1038 		break;
1039 
1040 	case TIOCSFLAGS:
1041 		sc->sc_swflags = *(int *)data;
1042 		break;
1043 
1044 	case TIOCMSET:
1045 	case TIOCMBIS:
1046 	case TIOCMBIC:
1047 		tiocm_to_com(sc, cmd, *(int *)data);
1048 		break;
1049 
1050 	case TIOCMGET:
1051 		*(int *)data = com_to_tiocm(sc);
1052 		break;
1053 
1054 	case PPS_IOC_CREATE:
1055 	case PPS_IOC_DESTROY:
1056 	case PPS_IOC_GETPARAMS:
1057 	case PPS_IOC_SETPARAMS:
1058 	case PPS_IOC_GETCAP:
1059 	case PPS_IOC_FETCH:
1060 #ifdef PPS_SYNC
1061 	case PPS_IOC_KCBIND:
1062 #endif
1063 		mutex_spin_enter(&timecounter_lock);
1064 		error = pps_ioctl(cmd, data, &sc->sc_pps_state);
1065 		mutex_spin_exit(&timecounter_lock);
1066 		break;
1067 
1068 	case TIOCDCDTIMESTAMP:	/* XXX old, overloaded  API used by xntpd v3 */
1069 		mutex_spin_enter(&timecounter_lock);
1070 #ifndef PPS_TRAILING_EDGE
1071 		TIMESPEC_TO_TIMEVAL((struct timeval *)data,
1072 		    &sc->sc_pps_state.ppsinfo.assert_timestamp);
1073 #else
1074 		TIMESPEC_TO_TIMEVAL((struct timeval *)data,
1075 		    &sc->sc_pps_state.ppsinfo.clear_timestamp);
1076 #endif
1077 		mutex_spin_exit(&timecounter_lock);
1078 		break;
1079 
1080 	default:
1081 		error = EPASSTHROUGH;
1082 		break;
1083 	}
1084 
1085 	mutex_spin_exit(&sc->sc_lock);
1086 
1087 #ifdef COM_DEBUG
1088 	if (com_debug)
1089 		comstatus(sc, "comioctl ");
1090 #endif
1091 
1092 	return (error);
1093 }
1094 
1095 integrate void
1096 com_schedrx(struct com_softc *sc)
1097 {
1098 
1099 	sc->sc_rx_ready = 1;
1100 
1101 	/* Wake up the poller. */
1102 	softint_schedule(sc->sc_si);
1103 }
1104 
1105 void
1106 com_break(struct com_softc *sc, int onoff)
1107 {
1108 
1109 	if (onoff)
1110 		SET(sc->sc_lcr, LCR_SBREAK);
1111 	else
1112 		CLR(sc->sc_lcr, LCR_SBREAK);
1113 
1114 	if (!sc->sc_heldchange) {
1115 		if (sc->sc_tx_busy) {
1116 			sc->sc_heldtbc = sc->sc_tbc;
1117 			sc->sc_tbc = 0;
1118 			sc->sc_heldchange = 1;
1119 		} else
1120 			com_loadchannelregs(sc);
1121 	}
1122 }
1123 
1124 void
1125 com_modem(struct com_softc *sc, int onoff)
1126 {
1127 
1128 	if (sc->sc_mcr_dtr == 0)
1129 		return;
1130 
1131 	if (onoff)
1132 		SET(sc->sc_mcr, sc->sc_mcr_dtr);
1133 	else
1134 		CLR(sc->sc_mcr, sc->sc_mcr_dtr);
1135 
1136 	if (!sc->sc_heldchange) {
1137 		if (sc->sc_tx_busy) {
1138 			sc->sc_heldtbc = sc->sc_tbc;
1139 			sc->sc_tbc = 0;
1140 			sc->sc_heldchange = 1;
1141 		} else
1142 			com_loadchannelregs(sc);
1143 	}
1144 }
1145 
1146 void
1147 tiocm_to_com(struct com_softc *sc, u_long how, int ttybits)
1148 {
1149 	u_char combits;
1150 
1151 	combits = 0;
1152 	if (ISSET(ttybits, TIOCM_DTR))
1153 		SET(combits, MCR_DTR);
1154 	if (ISSET(ttybits, TIOCM_RTS))
1155 		SET(combits, MCR_RTS);
1156 
1157 	switch (how) {
1158 	case TIOCMBIC:
1159 		CLR(sc->sc_mcr, combits);
1160 		break;
1161 
1162 	case TIOCMBIS:
1163 		SET(sc->sc_mcr, combits);
1164 		break;
1165 
1166 	case TIOCMSET:
1167 		CLR(sc->sc_mcr, MCR_DTR | MCR_RTS);
1168 		SET(sc->sc_mcr, combits);
1169 		break;
1170 	}
1171 
1172 	if (!sc->sc_heldchange) {
1173 		if (sc->sc_tx_busy) {
1174 			sc->sc_heldtbc = sc->sc_tbc;
1175 			sc->sc_tbc = 0;
1176 			sc->sc_heldchange = 1;
1177 		} else
1178 			com_loadchannelregs(sc);
1179 	}
1180 }
1181 
1182 int
1183 com_to_tiocm(struct com_softc *sc)
1184 {
1185 	u_char combits;
1186 	int ttybits = 0;
1187 
1188 	combits = sc->sc_mcr;
1189 	if (ISSET(combits, MCR_DTR))
1190 		SET(ttybits, TIOCM_DTR);
1191 	if (ISSET(combits, MCR_RTS))
1192 		SET(ttybits, TIOCM_RTS);
1193 
1194 	combits = sc->sc_msr;
1195 	if (ISSET(combits, MSR_DCD))
1196 		SET(ttybits, TIOCM_CD);
1197 	if (ISSET(combits, MSR_CTS))
1198 		SET(ttybits, TIOCM_CTS);
1199 	if (ISSET(combits, MSR_DSR))
1200 		SET(ttybits, TIOCM_DSR);
1201 	if (ISSET(combits, MSR_RI | MSR_TERI))
1202 		SET(ttybits, TIOCM_RI);
1203 
1204 	if (ISSET(sc->sc_ier, IER_ERXRDY | IER_ETXRDY | IER_ERLS | IER_EMSC))
1205 		SET(ttybits, TIOCM_LE);
1206 
1207 	return (ttybits);
1208 }
1209 
1210 static u_char
1211 cflag2lcr(tcflag_t cflag)
1212 {
1213 	u_char lcr = 0;
1214 
1215 	switch (ISSET(cflag, CSIZE)) {
1216 	case CS5:
1217 		SET(lcr, LCR_5BITS);
1218 		break;
1219 	case CS6:
1220 		SET(lcr, LCR_6BITS);
1221 		break;
1222 	case CS7:
1223 		SET(lcr, LCR_7BITS);
1224 		break;
1225 	case CS8:
1226 		SET(lcr, LCR_8BITS);
1227 		break;
1228 	}
1229 	if (ISSET(cflag, PARENB)) {
1230 		SET(lcr, LCR_PENAB);
1231 		if (!ISSET(cflag, PARODD))
1232 			SET(lcr, LCR_PEVEN);
1233 	}
1234 	if (ISSET(cflag, CSTOPB))
1235 		SET(lcr, LCR_STOPB);
1236 
1237 	return (lcr);
1238 }
1239 
1240 int
1241 comparam(struct tty *tp, struct termios *t)
1242 {
1243 	struct com_softc *sc =
1244 	    device_lookup_private(&com_cd, COMUNIT(tp->t_dev));
1245 	int ospeed;
1246 	u_char lcr;
1247 
1248 	if (COM_ISALIVE(sc) == 0)
1249 		return (EIO);
1250 
1251 #ifdef COM_HAYESP
1252 	if (sc->sc_type == COM_TYPE_HAYESP) {
1253 		int prescaler, speed;
1254 
1255 		/*
1256 		 * Calculate UART clock prescaler.  It should be in
1257 		 * range of 0 .. 3.
1258 		 */
1259 		for (prescaler = 0, speed = t->c_ospeed; prescaler < 4;
1260 		    prescaler++, speed /= 2)
1261 			if ((ospeed = comspeed(speed, sc->sc_frequency,
1262 					       sc->sc_type)) > 0)
1263 				break;
1264 
1265 		if (prescaler == 4)
1266 			return (EINVAL);
1267 		sc->sc_prescaler = prescaler;
1268 	} else
1269 #endif
1270 	ospeed = comspeed(t->c_ospeed, sc->sc_frequency, sc->sc_type);
1271 
1272 	/* Check requested parameters. */
1273 	if (ospeed < 0)
1274 		return (EINVAL);
1275 	if (t->c_ispeed && t->c_ispeed != t->c_ospeed)
1276 		return (EINVAL);
1277 
1278 	/*
1279 	 * For the console, always force CLOCAL and !HUPCL, so that the port
1280 	 * is always active.
1281 	 */
1282 	if (ISSET(sc->sc_swflags, TIOCFLAG_SOFTCAR) ||
1283 	    ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
1284 		SET(t->c_cflag, CLOCAL);
1285 		CLR(t->c_cflag, HUPCL);
1286 	}
1287 
1288 	/*
1289 	 * If there were no changes, don't do anything.  This avoids dropping
1290 	 * input and improves performance when all we did was frob things like
1291 	 * VMIN and VTIME.
1292 	 */
1293 	if (tp->t_ospeed == t->c_ospeed &&
1294 	    tp->t_cflag == t->c_cflag)
1295 		return (0);
1296 
1297 	lcr = ISSET(sc->sc_lcr, LCR_SBREAK) | cflag2lcr(t->c_cflag);
1298 
1299 	mutex_spin_enter(&sc->sc_lock);
1300 
1301 	sc->sc_lcr = lcr;
1302 
1303 	/*
1304 	 * If we're not in a mode that assumes a connection is present, then
1305 	 * ignore carrier changes.
1306 	 */
1307 	if (ISSET(t->c_cflag, CLOCAL | MDMBUF))
1308 		sc->sc_msr_dcd = 0;
1309 	else
1310 		sc->sc_msr_dcd = MSR_DCD;
1311 	/*
1312 	 * Set the flow control pins depending on the current flow control
1313 	 * mode.
1314 	 */
1315 	if (ISSET(t->c_cflag, CRTSCTS)) {
1316 		sc->sc_mcr_dtr = MCR_DTR;
1317 		sc->sc_mcr_rts = MCR_RTS;
1318 		sc->sc_msr_cts = MSR_CTS;
1319 		sc->sc_efr = EFR_AUTORTS | EFR_AUTOCTS;
1320 	} else if (ISSET(t->c_cflag, MDMBUF)) {
1321 		/*
1322 		 * For DTR/DCD flow control, make sure we don't toggle DTR for
1323 		 * carrier detection.
1324 		 */
1325 		sc->sc_mcr_dtr = 0;
1326 		sc->sc_mcr_rts = MCR_DTR;
1327 		sc->sc_msr_cts = MSR_DCD;
1328 		sc->sc_efr = 0;
1329 	} else {
1330 		/*
1331 		 * If no flow control, then always set RTS.  This will make
1332 		 * the other side happy if it mistakenly thinks we're doing
1333 		 * RTS/CTS flow control.
1334 		 */
1335 		sc->sc_mcr_dtr = MCR_DTR | MCR_RTS;
1336 		sc->sc_mcr_rts = 0;
1337 		sc->sc_msr_cts = 0;
1338 		sc->sc_efr = 0;
1339 		if (ISSET(sc->sc_mcr, MCR_DTR))
1340 			SET(sc->sc_mcr, MCR_RTS);
1341 		else
1342 			CLR(sc->sc_mcr, MCR_RTS);
1343 	}
1344 	sc->sc_msr_mask = sc->sc_msr_cts | sc->sc_msr_dcd;
1345 
1346 #if 0
1347 	if (ospeed == 0)
1348 		CLR(sc->sc_mcr, sc->sc_mcr_dtr);
1349 	else
1350 		SET(sc->sc_mcr, sc->sc_mcr_dtr);
1351 #endif
1352 
1353 	sc->sc_dlbl = ospeed;
1354 	sc->sc_dlbh = ospeed >> 8;
1355 
1356 	/*
1357 	 * Set the FIFO threshold based on the receive speed.
1358 	 *
1359 	 *  * If it's a low speed, it's probably a mouse or some other
1360 	 *    interactive device, so set the threshold low.
1361 	 *  * If it's a high speed, trim the trigger level down to prevent
1362 	 *    overflows.
1363 	 *  * Otherwise set it a bit higher.
1364 	 */
1365 	if (sc->sc_type == COM_TYPE_HAYESP)
1366 		sc->sc_fifo = FIFO_DMA_MODE | FIFO_ENABLE | FIFO_TRIGGER_8;
1367 	else if (ISSET(sc->sc_hwflags, COM_HW_FIFO)) {
1368 		if (t->c_ospeed <= 1200)
1369 			sc->sc_fifo = FIFO_ENABLE | FIFO_TRIGGER_1;
1370 		else if (t->c_ospeed <= 38400)
1371 			sc->sc_fifo = FIFO_ENABLE | FIFO_TRIGGER_8;
1372 		else
1373 			sc->sc_fifo = FIFO_ENABLE | FIFO_TRIGGER_4;
1374 	} else
1375 		sc->sc_fifo = 0;
1376 
1377 	/* And copy to tty. */
1378 	tp->t_ispeed = t->c_ospeed;
1379 	tp->t_ospeed = t->c_ospeed;
1380 	tp->t_cflag = t->c_cflag;
1381 
1382 	if (!sc->sc_heldchange) {
1383 		if (sc->sc_tx_busy) {
1384 			sc->sc_heldtbc = sc->sc_tbc;
1385 			sc->sc_tbc = 0;
1386 			sc->sc_heldchange = 1;
1387 		} else
1388 			com_loadchannelregs(sc);
1389 	}
1390 
1391 	if (!ISSET(t->c_cflag, CHWFLOW)) {
1392 		/* Disable the high water mark. */
1393 		sc->sc_r_hiwat = 0;
1394 		sc->sc_r_lowat = 0;
1395 		if (ISSET(sc->sc_rx_flags, RX_TTY_OVERFLOWED)) {
1396 			CLR(sc->sc_rx_flags, RX_TTY_OVERFLOWED);
1397 			com_schedrx(sc);
1398 		}
1399 		if (ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED|RX_IBUF_BLOCKED)) {
1400 			CLR(sc->sc_rx_flags, RX_TTY_BLOCKED|RX_IBUF_BLOCKED);
1401 			com_hwiflow(sc);
1402 		}
1403 	} else {
1404 		sc->sc_r_hiwat = com_rbuf_hiwat;
1405 		sc->sc_r_lowat = com_rbuf_lowat;
1406 	}
1407 
1408 	mutex_spin_exit(&sc->sc_lock);
1409 
1410 	/*
1411 	 * Update the tty layer's idea of the carrier bit, in case we changed
1412 	 * CLOCAL or MDMBUF.  We don't hang up here; we only do that by
1413 	 * explicit request.
1414 	 */
1415 	(void) (*tp->t_linesw->l_modem)(tp, ISSET(sc->sc_msr, MSR_DCD));
1416 
1417 #ifdef COM_DEBUG
1418 	if (com_debug)
1419 		comstatus(sc, "comparam ");
1420 #endif
1421 
1422 	if (!ISSET(t->c_cflag, CHWFLOW)) {
1423 		if (sc->sc_tx_stopped) {
1424 			sc->sc_tx_stopped = 0;
1425 			comstart(tp);
1426 		}
1427 	}
1428 
1429 	return (0);
1430 }
1431 
1432 void
1433 com_iflush(struct com_softc *sc)
1434 {
1435 	struct com_regs	*regsp = &sc->sc_regs;
1436 #ifdef DIAGNOSTIC
1437 	int reg;
1438 #endif
1439 	int timo;
1440 
1441 #ifdef DIAGNOSTIC
1442 	reg = 0xffff;
1443 #endif
1444 	timo = 50000;
1445 	/* flush any pending I/O */
1446 	while (ISSET(CSR_READ_1(regsp, COM_REG_LSR), LSR_RXRDY)
1447 	    && --timo)
1448 #ifdef DIAGNOSTIC
1449 		reg =
1450 #else
1451 		    (void)
1452 #endif
1453 		    CSR_READ_1(regsp, COM_REG_RXDATA);
1454 #ifdef DIAGNOSTIC
1455 	if (!timo)
1456 		aprint_error_dev(sc->sc_dev, "com_iflush timeout %02x\n", reg);
1457 #endif
1458 }
1459 
1460 void
1461 com_loadchannelregs(struct com_softc *sc)
1462 {
1463 	struct com_regs *regsp = &sc->sc_regs;
1464 
1465 	/* XXXXX necessary? */
1466 	com_iflush(sc);
1467 
1468 	if (sc->sc_type == COM_TYPE_PXA2x0)
1469 		CSR_WRITE_1(regsp, COM_REG_IER, IER_EUART);
1470 	else
1471 		CSR_WRITE_1(regsp, COM_REG_IER, 0);
1472 
1473 	if (sc->sc_type == COM_TYPE_OMAP) {
1474 		/* disable before changing settings */
1475 		CSR_WRITE_1(regsp, COM_REG_MDR1, MDR1_MODE_DISABLE);
1476 	}
1477 
1478 	if (ISSET(sc->sc_hwflags, COM_HW_FLOW)) {
1479 		KASSERT(sc->sc_type != COM_TYPE_AU1x00);
1480 		KASSERT(sc->sc_type != COM_TYPE_16550_NOERS);
1481 		/* no EFR on alchemy */
1482 		CSR_WRITE_1(regsp, COM_REG_LCR, LCR_EERS);
1483 		CSR_WRITE_1(regsp, COM_REG_EFR, sc->sc_efr);
1484 	}
1485 	if (sc->sc_type == COM_TYPE_AU1x00) {
1486 		/* alchemy has single separate 16-bit clock divisor register */
1487 		CSR_WRITE_2(regsp, COM_REG_DLBL, sc->sc_dlbl +
1488 		    (sc->sc_dlbh << 8));
1489 	} else {
1490 		CSR_WRITE_1(regsp, COM_REG_LCR, sc->sc_lcr | LCR_DLAB);
1491 		CSR_WRITE_1(regsp, COM_REG_DLBL, sc->sc_dlbl);
1492 		CSR_WRITE_1(regsp, COM_REG_DLBH, sc->sc_dlbh);
1493 	}
1494 	CSR_WRITE_1(regsp, COM_REG_LCR, sc->sc_lcr);
1495 	CSR_WRITE_1(regsp, COM_REG_MCR, sc->sc_mcr_active = sc->sc_mcr);
1496 	CSR_WRITE_1(regsp, COM_REG_FIFO, sc->sc_fifo);
1497 #ifdef COM_HAYESP
1498 	if (sc->sc_type == COM_TYPE_HAYESP) {
1499 		bus_space_write_1(regsp->cr_iot, sc->sc_hayespioh, HAYESP_CMD1,
1500 		    HAYESP_SETPRESCALER);
1501 		bus_space_write_1(regsp->cr_iot, sc->sc_hayespioh, HAYESP_CMD2,
1502 		    sc->sc_prescaler);
1503 	}
1504 #endif
1505 	if (sc->sc_type == COM_TYPE_OMAP) {
1506 		/* setup the fifos.  the FCR value is not used as long
1507 		   as SCR[6] and SCR[7] are 0, which they are at reset
1508 		   and we never touch the SCR register */
1509 		uint8_t rx_fifo_trig = 40;
1510 		uint8_t tx_fifo_trig = 60;
1511 		uint8_t rx_start = 8;
1512 		uint8_t rx_halt = 60;
1513 		uint8_t tlr_value = ((rx_fifo_trig>>2) << 4) | (tx_fifo_trig>>2);
1514 		uint8_t tcr_value = ((rx_start>>2) << 4) | (rx_halt>>2);
1515 
1516 		/* enable access to TCR & TLR */
1517 		CSR_WRITE_1(regsp, COM_REG_MCR, sc->sc_mcr | MCR_TCR_TLR);
1518 
1519 		/* write tcr and tlr values */
1520 		CSR_WRITE_1(regsp, COM_REG_TLR, tlr_value);
1521 		CSR_WRITE_1(regsp, COM_REG_TCR, tcr_value);
1522 
1523 		/* disable access to TCR & TLR */
1524 		CSR_WRITE_1(regsp, COM_REG_MCR, sc->sc_mcr);
1525 
1526 		/* enable again, but mode is based on speed */
1527 		if (sc->sc_tty->t_termios.c_ospeed > 230400) {
1528 			CSR_WRITE_1(regsp, COM_REG_MDR1, MDR1_MODE_UART_13X);
1529 		} else {
1530 			CSR_WRITE_1(regsp, COM_REG_MDR1, MDR1_MODE_UART_16X);
1531 		}
1532 	}
1533 
1534 	CSR_WRITE_1(regsp, COM_REG_IER, sc->sc_ier);
1535 }
1536 
1537 int
1538 comhwiflow(struct tty *tp, int block)
1539 {
1540 	struct com_softc *sc =
1541 	    device_lookup_private(&com_cd, COMUNIT(tp->t_dev));
1542 
1543 	if (COM_ISALIVE(sc) == 0)
1544 		return (0);
1545 
1546 	if (sc->sc_mcr_rts == 0)
1547 		return (0);
1548 
1549 	mutex_spin_enter(&sc->sc_lock);
1550 
1551 	if (block) {
1552 		if (!ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED)) {
1553 			SET(sc->sc_rx_flags, RX_TTY_BLOCKED);
1554 			com_hwiflow(sc);
1555 		}
1556 	} else {
1557 		if (ISSET(sc->sc_rx_flags, RX_TTY_OVERFLOWED)) {
1558 			CLR(sc->sc_rx_flags, RX_TTY_OVERFLOWED);
1559 			com_schedrx(sc);
1560 		}
1561 		if (ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED)) {
1562 			CLR(sc->sc_rx_flags, RX_TTY_BLOCKED);
1563 			com_hwiflow(sc);
1564 		}
1565 	}
1566 
1567 	mutex_spin_exit(&sc->sc_lock);
1568 	return (1);
1569 }
1570 
1571 /*
1572  * (un)block input via hw flowcontrol
1573  */
1574 void
1575 com_hwiflow(struct com_softc *sc)
1576 {
1577 	struct com_regs *regsp= &sc->sc_regs;
1578 
1579 	if (sc->sc_mcr_rts == 0)
1580 		return;
1581 
1582 	if (ISSET(sc->sc_rx_flags, RX_ANY_BLOCK)) {
1583 		CLR(sc->sc_mcr, sc->sc_mcr_rts);
1584 		CLR(sc->sc_mcr_active, sc->sc_mcr_rts);
1585 	} else {
1586 		SET(sc->sc_mcr, sc->sc_mcr_rts);
1587 		SET(sc->sc_mcr_active, sc->sc_mcr_rts);
1588 	}
1589 	CSR_WRITE_1(regsp, COM_REG_MCR, sc->sc_mcr_active);
1590 }
1591 
1592 
1593 void
1594 comstart(struct tty *tp)
1595 {
1596 	struct com_softc *sc =
1597 	    device_lookup_private(&com_cd, COMUNIT(tp->t_dev));
1598 	struct com_regs *regsp = &sc->sc_regs;
1599 	int s;
1600 
1601 	if (COM_ISALIVE(sc) == 0)
1602 		return;
1603 
1604 	s = spltty();
1605 	if (ISSET(tp->t_state, TS_BUSY | TS_TIMEOUT | TS_TTSTOP))
1606 		goto out;
1607 	if (sc->sc_tx_stopped)
1608 		goto out;
1609 	if (!ttypull(tp))
1610 		goto out;
1611 
1612 	/* Grab the first contiguous region of buffer space. */
1613 	{
1614 		u_char *tba;
1615 		int tbc;
1616 
1617 		tba = tp->t_outq.c_cf;
1618 		tbc = ndqb(&tp->t_outq, 0);
1619 
1620 		mutex_spin_enter(&sc->sc_lock);
1621 
1622 		sc->sc_tba = tba;
1623 		sc->sc_tbc = tbc;
1624 	}
1625 
1626 	SET(tp->t_state, TS_BUSY);
1627 	sc->sc_tx_busy = 1;
1628 
1629 	/* Enable transmit completion interrupts if necessary. */
1630 	if (!ISSET(sc->sc_ier, IER_ETXRDY)) {
1631 		SET(sc->sc_ier, IER_ETXRDY);
1632 		CSR_WRITE_1(regsp, COM_REG_IER, sc->sc_ier);
1633 	}
1634 
1635 	/* Output the first chunk of the contiguous buffer. */
1636 	if (!ISSET(sc->sc_hwflags, COM_HW_NO_TXPRELOAD)) {
1637 		u_int n;
1638 
1639 		n = sc->sc_tbc;
1640 		if (n > sc->sc_fifolen)
1641 			n = sc->sc_fifolen;
1642 		CSR_WRITE_MULTI(regsp, COM_REG_TXDATA, sc->sc_tba, n);
1643 		sc->sc_tbc -= n;
1644 		sc->sc_tba += n;
1645 	}
1646 
1647 	mutex_spin_exit(&sc->sc_lock);
1648 out:
1649 	splx(s);
1650 	return;
1651 }
1652 
1653 /*
1654  * Stop output on a line.
1655  */
1656 void
1657 comstop(struct tty *tp, int flag)
1658 {
1659 	struct com_softc *sc =
1660 	    device_lookup_private(&com_cd, COMUNIT(tp->t_dev));
1661 
1662 	mutex_spin_enter(&sc->sc_lock);
1663 	if (ISSET(tp->t_state, TS_BUSY)) {
1664 		/* Stop transmitting at the next chunk. */
1665 		sc->sc_tbc = 0;
1666 		sc->sc_heldtbc = 0;
1667 		if (!ISSET(tp->t_state, TS_TTSTOP))
1668 			SET(tp->t_state, TS_FLUSH);
1669 	}
1670 	mutex_spin_exit(&sc->sc_lock);
1671 }
1672 
1673 void
1674 comdiag(void *arg)
1675 {
1676 	struct com_softc *sc = arg;
1677 	int overflows, floods;
1678 
1679 	mutex_spin_enter(&sc->sc_lock);
1680 	overflows = sc->sc_overflows;
1681 	sc->sc_overflows = 0;
1682 	floods = sc->sc_floods;
1683 	sc->sc_floods = 0;
1684 	sc->sc_errors = 0;
1685 	mutex_spin_exit(&sc->sc_lock);
1686 
1687 	log(LOG_WARNING, "%s: %d silo overflow%s, %d ibuf flood%s\n",
1688 	    device_xname(sc->sc_dev),
1689 	    overflows, overflows == 1 ? "" : "s",
1690 	    floods, floods == 1 ? "" : "s");
1691 }
1692 
1693 integrate void
1694 com_rxsoft(struct com_softc *sc, struct tty *tp)
1695 {
1696 	int (*rint)(int, struct tty *) = tp->t_linesw->l_rint;
1697 	u_char *get, *end;
1698 	u_int cc, scc;
1699 	u_char lsr;
1700 	int code;
1701 
1702 	end = sc->sc_ebuf;
1703 	get = sc->sc_rbget;
1704 	scc = cc = com_rbuf_size - sc->sc_rbavail;
1705 
1706 	if (cc == com_rbuf_size) {
1707 		sc->sc_floods++;
1708 		if (sc->sc_errors++ == 0)
1709 			callout_reset(&sc->sc_diag_callout, 60 * hz,
1710 			    comdiag, sc);
1711 	}
1712 
1713 	/* If not yet open, drop the entire buffer content here */
1714 	if (!ISSET(tp->t_state, TS_ISOPEN)) {
1715 		get += cc << 1;
1716 		if (get >= end)
1717 			get -= com_rbuf_size << 1;
1718 		cc = 0;
1719 	}
1720 	while (cc) {
1721 		code = get[0];
1722 		lsr = get[1];
1723 		if (ISSET(lsr, LSR_OE | LSR_BI | LSR_FE | LSR_PE)) {
1724 			if (ISSET(lsr, LSR_OE)) {
1725 				sc->sc_overflows++;
1726 				if (sc->sc_errors++ == 0)
1727 					callout_reset(&sc->sc_diag_callout,
1728 					    60 * hz, comdiag, sc);
1729 			}
1730 			if (ISSET(lsr, LSR_BI | LSR_FE))
1731 				SET(code, TTY_FE);
1732 			if (ISSET(lsr, LSR_PE))
1733 				SET(code, TTY_PE);
1734 		}
1735 		if ((*rint)(code, tp) == -1) {
1736 			/*
1737 			 * The line discipline's buffer is out of space.
1738 			 */
1739 			if (!ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED)) {
1740 				/*
1741 				 * We're either not using flow control, or the
1742 				 * line discipline didn't tell us to block for
1743 				 * some reason.  Either way, we have no way to
1744 				 * know when there's more space available, so
1745 				 * just drop the rest of the data.
1746 				 */
1747 				get += cc << 1;
1748 				if (get >= end)
1749 					get -= com_rbuf_size << 1;
1750 				cc = 0;
1751 			} else {
1752 				/*
1753 				 * Don't schedule any more receive processing
1754 				 * until the line discipline tells us there's
1755 				 * space available (through comhwiflow()).
1756 				 * Leave the rest of the data in the input
1757 				 * buffer.
1758 				 */
1759 				SET(sc->sc_rx_flags, RX_TTY_OVERFLOWED);
1760 			}
1761 			break;
1762 		}
1763 		get += 2;
1764 		if (get >= end)
1765 			get = sc->sc_rbuf;
1766 		cc--;
1767 	}
1768 
1769 	if (cc != scc) {
1770 		sc->sc_rbget = get;
1771 		mutex_spin_enter(&sc->sc_lock);
1772 
1773 		cc = sc->sc_rbavail += scc - cc;
1774 		/* Buffers should be ok again, release possible block. */
1775 		if (cc >= sc->sc_r_lowat) {
1776 			if (ISSET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED)) {
1777 				CLR(sc->sc_rx_flags, RX_IBUF_OVERFLOWED);
1778 				SET(sc->sc_ier, IER_ERXRDY);
1779 #ifdef COM_PXA2X0
1780 				if (sc->sc_type == COM_TYPE_PXA2x0)
1781 					SET(sc->sc_ier, IER_ERXTOUT);
1782 #endif
1783 				CSR_WRITE_1(&sc->sc_regs, COM_REG_IER, sc->sc_ier);
1784 			}
1785 			if (ISSET(sc->sc_rx_flags, RX_IBUF_BLOCKED)) {
1786 				CLR(sc->sc_rx_flags, RX_IBUF_BLOCKED);
1787 				com_hwiflow(sc);
1788 			}
1789 		}
1790 		mutex_spin_exit(&sc->sc_lock);
1791 	}
1792 }
1793 
1794 integrate void
1795 com_txsoft(struct com_softc *sc, struct tty *tp)
1796 {
1797 
1798 	CLR(tp->t_state, TS_BUSY);
1799 	if (ISSET(tp->t_state, TS_FLUSH))
1800 		CLR(tp->t_state, TS_FLUSH);
1801 	else
1802 		ndflush(&tp->t_outq, (int)(sc->sc_tba - tp->t_outq.c_cf));
1803 	(*tp->t_linesw->l_start)(tp);
1804 }
1805 
1806 integrate void
1807 com_stsoft(struct com_softc *sc, struct tty *tp)
1808 {
1809 	u_char msr, delta;
1810 
1811 	mutex_spin_enter(&sc->sc_lock);
1812 	msr = sc->sc_msr;
1813 	delta = sc->sc_msr_delta;
1814 	sc->sc_msr_delta = 0;
1815 	mutex_spin_exit(&sc->sc_lock);
1816 
1817 	if (ISSET(delta, sc->sc_msr_dcd)) {
1818 		/*
1819 		 * Inform the tty layer that carrier detect changed.
1820 		 */
1821 		(void) (*tp->t_linesw->l_modem)(tp, ISSET(msr, MSR_DCD));
1822 	}
1823 
1824 	if (ISSET(delta, sc->sc_msr_cts)) {
1825 		/* Block or unblock output according to flow control. */
1826 		if (ISSET(msr, sc->sc_msr_cts)) {
1827 			sc->sc_tx_stopped = 0;
1828 			(*tp->t_linesw->l_start)(tp);
1829 		} else {
1830 			sc->sc_tx_stopped = 1;
1831 		}
1832 	}
1833 
1834 #ifdef COM_DEBUG
1835 	if (com_debug)
1836 		comstatus(sc, "com_stsoft");
1837 #endif
1838 }
1839 
1840 void
1841 comsoft(void *arg)
1842 {
1843 	struct com_softc *sc = arg;
1844 	struct tty *tp;
1845 
1846 	if (COM_ISALIVE(sc) == 0)
1847 		return;
1848 
1849 	tp = sc->sc_tty;
1850 
1851 	if (sc->sc_rx_ready) {
1852 		sc->sc_rx_ready = 0;
1853 		com_rxsoft(sc, tp);
1854 	}
1855 
1856 	if (sc->sc_st_check) {
1857 		sc->sc_st_check = 0;
1858 		com_stsoft(sc, tp);
1859 	}
1860 
1861 	if (sc->sc_tx_done) {
1862 		sc->sc_tx_done = 0;
1863 		com_txsoft(sc, tp);
1864 	}
1865 }
1866 
1867 int
1868 comintr(void *arg)
1869 {
1870 	struct com_softc *sc = arg;
1871 	struct com_regs *regsp = &sc->sc_regs;
1872 
1873 	u_char *put, *end;
1874 	u_int cc;
1875 	u_char lsr, iir;
1876 
1877 	if (COM_ISALIVE(sc) == 0)
1878 		return (0);
1879 
1880 	KASSERT(regsp != NULL);
1881 
1882 	mutex_spin_enter(&sc->sc_lock);
1883 	iir = CSR_READ_1(regsp, COM_REG_IIR);
1884 	if (ISSET(iir, IIR_NOPEND)) {
1885 		mutex_spin_exit(&sc->sc_lock);
1886 		return (0);
1887 	}
1888 
1889 	end = sc->sc_ebuf;
1890 	put = sc->sc_rbput;
1891 	cc = sc->sc_rbavail;
1892 
1893 again:	do {
1894 		u_char	msr, delta;
1895 
1896 		lsr = CSR_READ_1(regsp, COM_REG_LSR);
1897 		if (ISSET(lsr, LSR_BI)) {
1898 			int cn_trapped = 0;
1899 
1900 			cn_check_magic(sc->sc_tty->t_dev,
1901 				       CNC_BREAK, com_cnm_state);
1902 			if (cn_trapped)
1903 				continue;
1904 #if defined(KGDB) && !defined(DDB)
1905 			if (ISSET(sc->sc_hwflags, COM_HW_KGDB)) {
1906 				kgdb_connect(1);
1907 				continue;
1908 			}
1909 #endif
1910 		}
1911 
1912 		if (ISSET(lsr, LSR_RCV_MASK) &&
1913 		    !ISSET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED)) {
1914 			while (cc > 0) {
1915 				int cn_trapped = 0;
1916 				put[0] = CSR_READ_1(regsp, COM_REG_RXDATA);
1917 				put[1] = lsr;
1918 				cn_check_magic(sc->sc_tty->t_dev,
1919 					       put[0], com_cnm_state);
1920 				if (cn_trapped)
1921 					goto next;
1922 				put += 2;
1923 				if (put >= end)
1924 					put = sc->sc_rbuf;
1925 				cc--;
1926 			next:
1927 				lsr = CSR_READ_1(regsp, COM_REG_LSR);
1928 				if (!ISSET(lsr, LSR_RCV_MASK))
1929 					break;
1930 			}
1931 
1932 			/*
1933 			 * Current string of incoming characters ended because
1934 			 * no more data was available or we ran out of space.
1935 			 * Schedule a receive event if any data was received.
1936 			 * If we're out of space, turn off receive interrupts.
1937 			 */
1938 			sc->sc_rbput = put;
1939 			sc->sc_rbavail = cc;
1940 			if (!ISSET(sc->sc_rx_flags, RX_TTY_OVERFLOWED))
1941 				sc->sc_rx_ready = 1;
1942 
1943 			/*
1944 			 * See if we are in danger of overflowing a buffer. If
1945 			 * so, use hardware flow control to ease the pressure.
1946 			 */
1947 			if (!ISSET(sc->sc_rx_flags, RX_IBUF_BLOCKED) &&
1948 			    cc < sc->sc_r_hiwat) {
1949 				SET(sc->sc_rx_flags, RX_IBUF_BLOCKED);
1950 				com_hwiflow(sc);
1951 			}
1952 
1953 			/*
1954 			 * If we're out of space, disable receive interrupts
1955 			 * until the queue has drained a bit.
1956 			 */
1957 			if (!cc) {
1958 				SET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED);
1959 #ifdef COM_PXA2X0
1960 				if (sc->sc_type == COM_TYPE_PXA2x0)
1961 					CLR(sc->sc_ier, IER_ERXRDY|IER_ERXTOUT);
1962 				else
1963 #endif
1964 					CLR(sc->sc_ier, IER_ERXRDY);
1965 				CSR_WRITE_1(regsp, COM_REG_IER, sc->sc_ier);
1966 			}
1967 		} else {
1968 			if ((iir & (IIR_RXRDY|IIR_TXRDY)) == IIR_RXRDY) {
1969 				(void) CSR_READ_1(regsp, COM_REG_RXDATA);
1970 				continue;
1971 			}
1972 		}
1973 
1974 		msr = CSR_READ_1(regsp, COM_REG_MSR);
1975 		delta = msr ^ sc->sc_msr;
1976 		sc->sc_msr = msr;
1977 		if ((sc->sc_pps_state.ppsparam.mode & PPS_CAPTUREBOTH) &&
1978 		    (delta & MSR_DCD)) {
1979 			mutex_spin_enter(&timecounter_lock);
1980 			pps_capture(&sc->sc_pps_state);
1981 			pps_event(&sc->sc_pps_state,
1982 			    (msr & MSR_DCD) ?
1983 			    PPS_CAPTUREASSERT :
1984 			    PPS_CAPTURECLEAR);
1985 			mutex_spin_exit(&timecounter_lock);
1986 		}
1987 
1988 		/*
1989 		 * Process normal status changes
1990 		 */
1991 		if (ISSET(delta, sc->sc_msr_mask)) {
1992 			SET(sc->sc_msr_delta, delta);
1993 
1994 			/*
1995 			 * Stop output immediately if we lose the output
1996 			 * flow control signal or carrier detect.
1997 			 */
1998 			if (ISSET(~msr, sc->sc_msr_mask)) {
1999 				sc->sc_tbc = 0;
2000 				sc->sc_heldtbc = 0;
2001 #ifdef COM_DEBUG
2002 				if (com_debug)
2003 					comstatus(sc, "comintr  ");
2004 #endif
2005 			}
2006 
2007 			sc->sc_st_check = 1;
2008 		}
2009 	} while (!ISSET((iir =
2010 	    CSR_READ_1(regsp, COM_REG_IIR)), IIR_NOPEND) &&
2011 	    /*
2012 	     * Since some device (e.g., ST16C1550) doesn't clear IIR_TXRDY
2013 	     * by IIR read, so we can't do this way: `process all interrupts,
2014 	     * then do TX if possble'.
2015 	     */
2016 	    (iir & IIR_IMASK) != IIR_TXRDY);
2017 
2018 	/*
2019 	 * Read LSR again, since there may be an interrupt between
2020 	 * the last LSR read and IIR read above.
2021 	 */
2022 	lsr = CSR_READ_1(regsp, COM_REG_LSR);
2023 
2024 	/*
2025 	 * See if data can be transmitted as well.
2026 	 * Schedule tx done event if no data left
2027 	 * and tty was marked busy.
2028 	 */
2029 	if (ISSET(lsr, LSR_TXRDY)) {
2030 		/*
2031 		 * If we've delayed a parameter change, do it now, and restart
2032 		 * output.
2033 		 */
2034 		if (sc->sc_heldchange) {
2035 			com_loadchannelregs(sc);
2036 			sc->sc_heldchange = 0;
2037 			sc->sc_tbc = sc->sc_heldtbc;
2038 			sc->sc_heldtbc = 0;
2039 		}
2040 
2041 		/* Output the next chunk of the contiguous buffer, if any. */
2042 		if (sc->sc_tbc > 0) {
2043 			u_int n;
2044 
2045 			n = sc->sc_tbc;
2046 			if (n > sc->sc_fifolen)
2047 				n = sc->sc_fifolen;
2048 			CSR_WRITE_MULTI(regsp, COM_REG_TXDATA, sc->sc_tba, n);
2049 			sc->sc_tbc -= n;
2050 			sc->sc_tba += n;
2051 		} else {
2052 			/* Disable transmit completion interrupts if necessary. */
2053 			if (ISSET(sc->sc_ier, IER_ETXRDY)) {
2054 				CLR(sc->sc_ier, IER_ETXRDY);
2055 				CSR_WRITE_1(regsp, COM_REG_IER, sc->sc_ier);
2056 			}
2057 			if (sc->sc_tx_busy) {
2058 				sc->sc_tx_busy = 0;
2059 				sc->sc_tx_done = 1;
2060 			}
2061 		}
2062 	}
2063 
2064 	if (!ISSET((iir = CSR_READ_1(regsp, COM_REG_IIR)), IIR_NOPEND))
2065 		goto again;
2066 
2067 	mutex_spin_exit(&sc->sc_lock);
2068 
2069 	/* Wake up the poller. */
2070 	softint_schedule(sc->sc_si);
2071 
2072 #if NRND > 0 && defined(RND_COM)
2073 	rnd_add_uint32(&sc->rnd_source, iir | lsr);
2074 #endif
2075 
2076 	return (1);
2077 }
2078 
2079 /*
2080  * The following functions are polled getc and putc routines, shared
2081  * by the console and kgdb glue.
2082  *
2083  * The read-ahead code is so that you can detect pending in-band
2084  * cn_magic in polled mode while doing output rather than having to
2085  * wait until the kernel decides it needs input.
2086  */
2087 
2088 #define MAX_READAHEAD	20
2089 static int com_readahead[MAX_READAHEAD];
2090 static int com_readaheadcount = 0;
2091 
2092 int
2093 com_common_getc(dev_t dev, struct com_regs *regsp)
2094 {
2095 	int s = splserial();
2096 	u_char stat, c;
2097 
2098 	/* got a character from reading things earlier */
2099 	if (com_readaheadcount > 0) {
2100 		int i;
2101 
2102 		c = com_readahead[0];
2103 		for (i = 1; i < com_readaheadcount; i++) {
2104 			com_readahead[i-1] = com_readahead[i];
2105 		}
2106 		com_readaheadcount--;
2107 		splx(s);
2108 		return (c);
2109 	}
2110 
2111 	/* block until a character becomes available */
2112 	while (!ISSET(stat = CSR_READ_1(regsp, COM_REG_LSR), LSR_RXRDY))
2113 		;
2114 
2115 	c = CSR_READ_1(regsp, COM_REG_RXDATA);
2116 	stat = CSR_READ_1(regsp, COM_REG_IIR);
2117 	{
2118 		int cn_trapped = 0; /* unused */
2119 #ifdef DDB
2120 		extern int db_active;
2121 		if (!db_active)
2122 #endif
2123 			cn_check_magic(dev, c, com_cnm_state);
2124 	}
2125 	splx(s);
2126 	return (c);
2127 }
2128 
2129 static void
2130 com_common_putc(dev_t dev, struct com_regs *regsp, int c)
2131 {
2132 	int s = splserial();
2133 	int cin, stat, timo;
2134 
2135 	if (com_readaheadcount < MAX_READAHEAD
2136 	     && ISSET(stat = CSR_READ_1(regsp, COM_REG_LSR), LSR_RXRDY)) {
2137 		int cn_trapped = 0;
2138 		cin = CSR_READ_1(regsp, COM_REG_RXDATA);
2139 		stat = CSR_READ_1(regsp, COM_REG_IIR);
2140 		cn_check_magic(dev, cin, com_cnm_state);
2141 		com_readahead[com_readaheadcount++] = cin;
2142 	}
2143 
2144 	/* wait for any pending transmission to finish */
2145 	timo = 150000;
2146 	while (!ISSET(CSR_READ_1(regsp, COM_REG_LSR), LSR_TXRDY) && --timo)
2147 		continue;
2148 
2149 	CSR_WRITE_1(regsp, COM_REG_TXDATA, c);
2150 	COM_BARRIER(regsp, BR | BW);
2151 
2152 	splx(s);
2153 }
2154 
2155 /*
2156  * Initialize UART for use as console or KGDB line.
2157  */
2158 int
2159 cominit(struct com_regs *regsp, int rate, int frequency, int type,
2160     tcflag_t cflag)
2161 {
2162 
2163 	if (bus_space_map(regsp->cr_iot, regsp->cr_iobase, regsp->cr_nports, 0,
2164 		&regsp->cr_ioh))
2165 		return (ENOMEM); /* ??? */
2166 
2167 	if (type == COM_TYPE_OMAP) {
2168 		/* disable before changing settings */
2169 		CSR_WRITE_1(regsp, COM_REG_MDR1, MDR1_MODE_DISABLE);
2170 	}
2171 
2172 	rate = comspeed(rate, frequency, type);
2173 	if (type != COM_TYPE_AU1x00) {
2174 		/* no EFR on alchemy */
2175 		if (type != COM_TYPE_16550_NOERS) {
2176 			CSR_WRITE_1(regsp, COM_REG_LCR, LCR_EERS);
2177 			CSR_WRITE_1(regsp, COM_REG_EFR, 0);
2178 		}
2179 		CSR_WRITE_1(regsp, COM_REG_LCR, LCR_DLAB);
2180 		CSR_WRITE_1(regsp, COM_REG_DLBL, rate & 0xff);
2181 		CSR_WRITE_1(regsp, COM_REG_DLBH, rate >> 8);
2182 	} else {
2183 		CSR_WRITE_1(regsp, COM_REG_DLBL, rate);
2184 	}
2185 	CSR_WRITE_1(regsp, COM_REG_LCR, cflag2lcr(cflag));
2186 	CSR_WRITE_1(regsp, COM_REG_MCR, MCR_DTR | MCR_RTS);
2187 	CSR_WRITE_1(regsp, COM_REG_FIFO,
2188 	    FIFO_ENABLE | FIFO_RCV_RST | FIFO_XMT_RST | FIFO_TRIGGER_1);
2189 
2190 	if (type == COM_TYPE_OMAP) {
2191 		/* setup the fifos.  the FCR value is not used as long
2192 		   as SCR[6] and SCR[7] are 0, which they are at reset
2193 		   and we never touch the SCR register */
2194 		uint8_t rx_fifo_trig = 40;
2195 		uint8_t tx_fifo_trig = 60;
2196 		uint8_t rx_start = 8;
2197 		uint8_t rx_halt = 60;
2198 		uint8_t tlr_value = ((rx_fifo_trig>>2) << 4) | (tx_fifo_trig>>2);
2199 		uint8_t tcr_value = ((rx_start>>2) << 4) | (rx_halt>>2);
2200 
2201 		/* enable access to TCR & TLR */
2202 		CSR_WRITE_1(regsp, COM_REG_MCR, MCR_DTR | MCR_RTS | MCR_TCR_TLR);
2203 
2204 		/* write tcr and tlr values */
2205 		CSR_WRITE_1(regsp, COM_REG_TLR, tlr_value);
2206 		CSR_WRITE_1(regsp, COM_REG_TCR, tcr_value);
2207 
2208 		/* disable access to TCR & TLR */
2209 		CSR_WRITE_1(regsp, COM_REG_MCR, MCR_DTR | MCR_RTS);
2210 
2211 		/* enable again, but mode is based on speed */
2212 		if (rate > 230400) {
2213 			CSR_WRITE_1(regsp, COM_REG_MDR1, MDR1_MODE_UART_13X);
2214 		} else {
2215 			CSR_WRITE_1(regsp, COM_REG_MDR1, MDR1_MODE_UART_16X);
2216 		}
2217 	}
2218 
2219 #ifdef COM_PXA2X0
2220 	if (type == COM_TYPE_PXA2x0)
2221 		CSR_WRITE_1(regsp, COM_REG_IER, IER_EUART);
2222 	else
2223 #endif
2224 		CSR_WRITE_1(regsp, COM_REG_IER, 0);
2225 
2226 	return (0);
2227 }
2228 
2229 int
2230 comcnattach1(struct com_regs *regsp, int rate, int frequency, int type,
2231     tcflag_t cflag)
2232 {
2233 	int res;
2234 
2235 	comcons_info.regs = *regsp;
2236 
2237 	res = cominit(&comcons_info.regs, rate, frequency, type, cflag);
2238 	if (res)
2239 		return (res);
2240 
2241 	cn_tab = &comcons;
2242 	cn_init_magic(&com_cnm_state);
2243 	cn_set_magic("\047\001"); /* default magic is BREAK */
2244 
2245 	comcons_info.frequency = frequency;
2246 	comcons_info.type = type;
2247 	comcons_info.rate = rate;
2248 	comcons_info.cflag = cflag;
2249 
2250 	return (0);
2251 }
2252 
2253 int
2254 comcnattach(bus_space_tag_t iot, bus_addr_t iobase, int rate, int frequency,
2255     int type, tcflag_t cflag)
2256 {
2257 	struct com_regs	regs;
2258 
2259 	memset(&regs, 0, sizeof regs);
2260 	regs.cr_iot = iot;
2261 	regs.cr_iobase = iobase;
2262 	regs.cr_nports = COM_NPORTS;
2263 #ifdef	COM_REGMAP
2264 	memcpy(regs.cr_map, com_std_map, sizeof (regs.cr_map));
2265 #endif
2266 
2267 	return comcnattach1(&regs, rate, frequency, type, cflag);
2268 }
2269 
2270 static int
2271 comcnreattach(void)
2272 {
2273 	return comcnattach1(&comcons_info.regs, comcons_info.rate,
2274 	    comcons_info.frequency, comcons_info.type, comcons_info.cflag);
2275 }
2276 
2277 int
2278 comcngetc(dev_t dev)
2279 {
2280 
2281 	return (com_common_getc(dev, &comcons_info.regs));
2282 }
2283 
2284 /*
2285  * Console kernel output character routine.
2286  */
2287 void
2288 comcnputc(dev_t dev, int c)
2289 {
2290 
2291 	com_common_putc(dev, &comcons_info.regs, c);
2292 }
2293 
2294 void
2295 comcnpollc(dev_t dev, int on)
2296 {
2297 
2298 }
2299 
2300 #ifdef KGDB
2301 int
2302 com_kgdb_attach1(struct com_regs *regsp, int rate, int frequency, int type,
2303     tcflag_t cflag)
2304 {
2305 	int res;
2306 
2307 	if (bus_space_is_equal(regsp->cr_iot, comcons_info.regs.cr_iot) &&
2308 	    regsp->cr_iobase == comcons_info.regs.cr_iobase) {
2309 #if !defined(DDB)
2310 		return (EBUSY); /* cannot share with console */
2311 #else
2312 		comkgdbregs = *regsp;
2313 		comkgdbregs.cr_ioh = comcons_info.regs.cr_ioh;
2314 #endif
2315 	} else {
2316 		comkgdbregs = *regsp;
2317 		res = cominit(&comkgdbregs, rate, frequency, type, cflag);
2318 		if (res)
2319 			return (res);
2320 
2321 		/*
2322 		 * XXXfvdl this shouldn't be needed, but the cn_magic goo
2323 		 * expects this to be initialized
2324 		 */
2325 		cn_init_magic(&com_cnm_state);
2326 		cn_set_magic("\047\001");
2327 	}
2328 
2329 	kgdb_attach(com_kgdb_getc, com_kgdb_putc, NULL);
2330 	kgdb_dev = 123; /* unneeded, only to satisfy some tests */
2331 
2332 	return (0);
2333 }
2334 
2335 int
2336 com_kgdb_attach(bus_space_tag_t iot, bus_addr_t iobase, int rate,
2337     int frequency, int type, tcflag_t cflag)
2338 {
2339 	struct com_regs regs;
2340 
2341 	regs.cr_iot = iot;
2342 	regs.cr_nports = COM_NPORTS;
2343 	regs.cr_iobase = iobase;
2344 #ifdef COM_REGMAP
2345 	memcpy(regs.cr_map, com_std_map, sizeof (regs.cr_map));
2346 #endif
2347 
2348 	return com_kgdb_attach1(&regs, rate, frequency, type, cflag);
2349 }
2350 
2351 /* ARGSUSED */
2352 int
2353 com_kgdb_getc(void *arg)
2354 {
2355 
2356 	return (com_common_getc(NODEV, &comkgdbregs));
2357 }
2358 
2359 /* ARGSUSED */
2360 void
2361 com_kgdb_putc(void *arg, int c)
2362 {
2363 
2364 	com_common_putc(NODEV, &comkgdbregs, c);
2365 }
2366 #endif /* KGDB */
2367 
2368 /* helper function to identify the com ports used by
2369  console or KGDB (and not yet autoconf attached) */
2370 int
2371 com_is_console(bus_space_tag_t iot, bus_addr_t iobase, bus_space_handle_t *ioh)
2372 {
2373 	bus_space_handle_t help;
2374 
2375 	if (!comconsattached &&
2376 	    bus_space_is_equal(iot, comcons_info.regs.cr_iot) &&
2377 	    iobase == comcons_info.regs.cr_iobase)
2378 		help = comcons_info.regs.cr_ioh;
2379 #ifdef KGDB
2380 	else if (!com_kgdb_attached &&
2381 	    bus_space_is_equal(iot, comkgdbregs.cr_iot) &&
2382 	    iobase == comkgdbregs.cr_iobase)
2383 		help = comkgdbregs.cr_ioh;
2384 #endif
2385 	else
2386 		return (0);
2387 
2388 	if (ioh)
2389 		*ioh = help;
2390 	return (1);
2391 }
2392 
2393 /*
2394  * this routine exists to serve as a shutdown hook for systems that
2395  * have firmware which doesn't interact properly with a com device in
2396  * FIFO mode.
2397  */
2398 bool
2399 com_cleanup(device_t self, int how)
2400 {
2401 	struct com_softc *sc = device_private(self);
2402 
2403 	if (ISSET(sc->sc_hwflags, COM_HW_FIFO))
2404 		CSR_WRITE_1(&sc->sc_regs, COM_REG_FIFO, 0);
2405 
2406 	return true;
2407 }
2408 
2409 bool
2410 com_suspend(device_t self, const pmf_qual_t *qual)
2411 {
2412 	struct com_softc *sc = device_private(self);
2413 
2414 #if 0
2415 	if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE) && cn_tab == &comcons)
2416 		cn_tab = &comcons_suspend;
2417 #endif
2418 
2419 	CSR_WRITE_1(&sc->sc_regs, COM_REG_IER, 0);
2420 	(void)CSR_READ_1(&sc->sc_regs, COM_REG_IIR);
2421 
2422 	return true;
2423 }
2424 
2425 bool
2426 com_resume(device_t self, const pmf_qual_t *qual)
2427 {
2428 	struct com_softc *sc = device_private(self);
2429 
2430 	mutex_spin_enter(&sc->sc_lock);
2431 	com_loadchannelregs(sc);
2432 	mutex_spin_exit(&sc->sc_lock);
2433 
2434 	return true;
2435 }
2436