xref: /netbsd-src/sys/arch/arm/imx/imxuart.c (revision 4817a0b0b8fe9612e8ebe21a9bf2d97b95038a97)
1 /* $NetBSD: imxuart.c,v 1.6 2010/11/27 13:37:27 bsh Exp $ */
2 
3 /*
4  * Copyright (c) 2009, 2010  Genetec Corporation.  All rights reserved.
5  * Written by Hiroyuki Bessho for Genetec Corporation.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY GENETEC CORPORATION ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
18  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
19  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL GENETEC CORPORATION
20  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26  * POSSIBILITY OF SUCH DAMAGE.
27  *
28  */
29 
30 /*
31  * derived from sys/dev/ic/com.c
32  */
33 
34 /*-
35  * Copyright (c) 1998, 1999, 2004, 2008 The NetBSD Foundation, Inc.
36  * All rights reserved.
37  *
38  * This code is derived from software contributed to The NetBSD Foundation
39  * by Charles M. Hannum.
40  *
41  * Redistribution and use in source and binary forms, with or without
42  * modification, are permitted provided that the following conditions
43  * are met:
44  * 1. Redistributions of source code must retain the above copyright
45  *    notice, this list of conditions and the following disclaimer.
46  * 2. Redistributions in binary form must reproduce the above copyright
47  *    notice, this list of conditions and the following disclaimer in the
48  *    documentation and/or other materials provided with the distribution.
49  *
50  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
51  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
52  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
53  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
54  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
55  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
56  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
57  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
58  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
59  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
60  * POSSIBILITY OF SUCH DAMAGE.
61  */
62 
63 /*
64  * Copyright (c) 1991 The Regents of the University of California.
65  * All rights reserved.
66  *
67  * Redistribution and use in source and binary forms, with or without
68  * modification, are permitted provided that the following conditions
69  * are met:
70  * 1. Redistributions of source code must retain the above copyright
71  *    notice, this list of conditions and the following disclaimer.
72  * 2. Redistributions in binary form must reproduce the above copyright
73  *    notice, this list of conditions and the following disclaimer in the
74  *    documentation and/or other materials provided with the distribution.
75  * 3. Neither the name of the University nor the names of its contributors
76  *    may be used to endorse or promote products derived from this software
77  *    without specific prior written permission.
78  *
79  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
80  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
81  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
82  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
83  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
84  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
85  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
86  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
87  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
88  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
89  * SUCH DAMAGE.
90  *
91  *	@(#)com.c	7.5 (Berkeley) 5/16/91
92  */
93 
94 /*
95  * driver for UART in i.MX SoC.
96  */
97 
98 #include <sys/cdefs.h>
99 __KERNEL_RCSID(0, "$NetBSD: imxuart.c,v 1.6 2010/11/27 13:37:27 bsh Exp $");
100 
101 #include "opt_imxuart.h"
102 #include "opt_ddb.h"
103 #include "opt_kgdb.h"
104 #include "opt_lockdebug.h"
105 #include "opt_multiprocessor.h"
106 #include "opt_ntp.h"
107 #include "opt_imxuart.h"
108 #include "opt_imx.h"
109 
110 #include "rnd.h"
111 #if NRND > 0 && defined(RND_COM)
112 #include <sys/rnd.h>
113 #endif
114 
115 #ifndef	IMXUART_TOLERANCE
116 #define	IMXUART_TOLERANCE	30	/* baud rate tolerance, in 0.1% units */
117 #endif
118 
119 #ifndef	IMXUART_FREQDIV
120 #define	IMXUART_FREQDIV		2	/* XXX */
121 #endif
122 
123 #ifndef	IMXUART_FREQ
124 #define	IMXUART_FREQ	(56900000)
125 #endif
126 
127 /*
128  * Override cnmagic(9) macro before including <sys/systm.h>.
129  * We need to know if cn_check_magic triggered debugger, so set a flag.
130  * Callers of cn_check_magic must declare int cn_trapped = 0;
131  * XXX: this is *ugly*!
132  */
133 #define	cn_trap()				\
134 	do {					\
135 		console_debugger();		\
136 		cn_trapped = 1;			\
137 	} while (/* CONSTCOND */ 0)
138 
139 #include <sys/param.h>
140 #include <sys/systm.h>
141 #include <sys/ioctl.h>
142 #include <sys/select.h>
143 #include <sys/poll.h>
144 #include <sys/tty.h>
145 #include <sys/proc.h>
146 #include <sys/user.h>
147 #include <sys/conf.h>
148 #include <sys/file.h>
149 #include <sys/uio.h>
150 #include <sys/kernel.h>
151 #include <sys/syslog.h>
152 #include <sys/device.h>
153 #include <sys/malloc.h>
154 #include <sys/timepps.h>
155 #include <sys/vnode.h>
156 #include <sys/kauth.h>
157 #include <sys/intr.h>
158 
159 #include <sys/bus.h>
160 
161 #include <arm/imx/imxuartreg.h>
162 #include <arm/imx/imxuartvar.h>
163 #include <dev/cons.h>
164 
165 #ifndef	IMXUART_RING_SIZE
166 #define	IMXUART_RING_SIZE	2048
167 #endif
168 
169 typedef struct imxuart_softc {
170 	device_t	sc_dev;
171 
172 	struct imxuart_regs {
173 		bus_space_tag_t		ur_iot;
174 		bus_space_handle_t	ur_ioh;
175 		bus_addr_t		ur_iobase;
176 #if 0
177 		bus_size_t		ur_nports;
178 		bus_size_t		ur_map[16];
179 #endif
180 	} sc_regs;
181 
182 #define	sc_bt	sc_regs.ur_iot
183 #define	sc_bh	sc_regs.ur_ioh
184 
185 	uint32_t		sc_intrspec_enb;
186 	uint32_t	sc_ucr2_d;	/* target value for UCR2 */
187 	uint32_t	sc_ucr[4];	/* cached value of UCRn */
188 #define	sc_ucr1	sc_ucr[0]
189 #define	sc_ucr2	sc_ucr[1]
190 #define	sc_ucr3	sc_ucr[2]
191 #define	sc_ucr4	sc_ucr[3]
192 
193 	uint			sc_init_cnt;
194 
195 	bus_addr_t		sc_addr;
196 	bus_size_t		sc_size;
197 	int			sc_intr;
198 
199 	u_char	sc_hwflags;
200 /* Hardware flag masks */
201 #define	IMXUART_HW_FLOW 	__BIT(0)
202 #define	IMXUART_HW_DEV_OK	__BIT(1)
203 #define	IMXUART_HW_CONSOLE	__BIT(2)
204 #define	IMXUART_HW_KGDB 	__BIT(3)
205 
206 
207 	bool	enabled;
208 
209 	u_char	sc_swflags;
210 
211 	u_char sc_rx_flags;
212 #define	IMXUART_RX_TTY_BLOCKED  	__BIT(0)
213 #define	IMXUART_RX_TTY_OVERFLOWED	__BIT(1)
214 #define	IMXUART_RX_IBUF_BLOCKED 	__BIT(2)
215 #define	IMXUART_RX_IBUF_OVERFLOWED	__BIT(3)
216 #define	IMXUART_RX_ANY_BLOCK					\
217 	(IMXUART_RX_TTY_BLOCKED|IMXUART_RX_TTY_OVERFLOWED| 	\
218 	    IMXUART_RX_IBUF_BLOCKED|IMXUART_RX_IBUF_OVERFLOWED)
219 
220 	bool	sc_tx_busy, sc_tx_done, sc_tx_stopped;
221 	bool	sc_rx_ready,sc_st_check;
222 	u_short	sc_txfifo_len, sc_txfifo_thresh;
223 
224 	uint16_t	*sc_rbuf;
225 	u_int		sc_rbuf_size;
226 	u_int		sc_rbuf_in;
227 	u_int		sc_rbuf_out;
228 #define	IMXUART_RBUF_AVAIL(sc)					\
229 	((sc->sc_rbuf_out <= sc->sc_rbuf_in) ?			\
230 	(sc->sc_rbuf_in - sc->sc_rbuf_out) :			\
231 	(sc->sc_rbuf_size - (sc->sc_rbuf_out - sc->sc_rbuf_in)))
232 
233 #define	IMXUART_RBUF_SPACE(sc)	\
234 	((sc->sc_rbuf_in <= sc->sc_rbuf_out ?			    \
235 	    sc->sc_rbuf_size - (sc->sc_rbuf_out - sc->sc_rbuf_in) : \
236 	    sc->sc_rbuf_in - sc->sc_rbuf_out) - 1)
237 /* increment ringbuffer pointer */
238 #define	IMXUART_RBUF_INC(sc,v,i)	(((v) + (i))&((sc->sc_rbuf_size)-1))
239 	u_int	sc_r_lowat;
240 	u_int	sc_r_hiwat;
241 
242 	/* output chunk */
243  	u_char *sc_tba;
244  	u_int sc_tbc;
245 	u_int sc_heldtbc;
246 	/* pending parameter changes */
247 	u_char	sc_pending;
248 #define	IMXUART_PEND_PARAM	__BIT(0)
249 #define	IMXUART_PEND_SPEED	__BIT(1)
250 
251 
252 	struct callout sc_diag_callout;
253 	kmutex_t sc_lock;
254 	void *sc_ih;		/* interrupt handler */
255 	void *sc_si;		/* soft interrupt */
256 	struct tty		*sc_tty;
257 
258 	/* power management hooks */
259 	int (*enable)(struct imxuart_softc *);
260 	void (*disable)(struct imxuart_softc *);
261 
262 	struct {
263 		ulong err;
264 		ulong brk;
265 		ulong prerr;
266 		ulong frmerr;
267 		ulong ovrrun;
268 	}	sc_errors;
269 
270 	struct imxuart_baudrate_ratio {
271 		uint16_t numerator;	/* UBIR */
272 		uint16_t modulator;	/* UBMR */
273 	} sc_ratio;
274 
275 } imxuart_softc_t;
276 
277 
278 int	imxuspeed(long, struct imxuart_baudrate_ratio *);
279 int	imxuparam(struct tty *, struct termios *);
280 void	imxustart(struct tty *);
281 int	imxuhwiflow(struct tty *, int);
282 
283 void	imxuart_shutdown(struct imxuart_softc *);
284 void	imxuart_loadchannelregs(struct imxuart_softc *);
285 void	imxuart_hwiflow(struct imxuart_softc *);
286 void	imxuart_break(struct imxuart_softc *, bool);
287 void	imxuart_modem(struct imxuart_softc *, int);
288 void	tiocm_to_imxu(struct imxuart_softc *, u_long, int);
289 int	imxuart_to_tiocm(struct imxuart_softc *);
290 void	imxuart_iflush(struct imxuart_softc *);
291 int	imxuintr(void *);
292 
293 int	imxuart_common_getc(dev_t, struct imxuart_regs *);
294 void	imxuart_common_putc(dev_t, struct imxuart_regs *, int);
295 
296 
297 int	imxuart_init(struct imxuart_regs *, int, tcflag_t);
298 
299 int	imxucngetc(dev_t);
300 void	imxucnputc(dev_t, int);
301 void	imxucnpollc(dev_t, int);
302 
303 static void imxuintr_read(struct imxuart_softc *);
304 static void imxuintr_send(struct imxuart_softc *);
305 
306 static void imxuart_enable_debugport(struct imxuart_softc *);
307 static void imxuart_disable_all_interrupts(struct imxuart_softc *);
308 static void imxuart_control_rxint(struct imxuart_softc *, bool);
309 static void imxuart_control_txint(struct imxuart_softc *, bool);
310 static u_int imxuart_txfifo_space(struct imxuart_softc *sc);
311 
312 static	uint32_t	cflag_to_ucr2(tcflag_t, uint32_t);
313 
314 CFATTACH_DECL_NEW(imxuart, sizeof(struct imxuart_softc),
315     imxuart_match, imxuart_attach, NULL, NULL);
316 
317 
318 #define	integrate	static inline
319 void 	imxusoft(void *);
320 integrate void imxuart_rxsoft(struct imxuart_softc *, struct tty *);
321 integrate void imxuart_txsoft(struct imxuart_softc *, struct tty *);
322 integrate void imxuart_stsoft(struct imxuart_softc *, struct tty *);
323 integrate void imxuart_schedrx(struct imxuart_softc *);
324 void	imxudiag(void *);
325 static void imxuart_load_speed(struct imxuart_softc *);
326 static void imxuart_load_params(struct imxuart_softc *);
327 integrate void imxuart_load_pendings(struct imxuart_softc *);
328 
329 
330 extern struct cfdriver imxuart_cd;
331 
332 dev_type_open(imxuopen);
333 dev_type_close(imxuclose);
334 dev_type_read(imxuread);
335 dev_type_write(imxuwrite);
336 dev_type_ioctl(imxuioctl);
337 dev_type_stop(imxustop);
338 dev_type_tty(imxutty);
339 dev_type_poll(imxupoll);
340 
341 const struct cdevsw imxcom_cdevsw = {
342 	imxuopen, imxuclose, imxuread, imxuwrite, imxuioctl,
343 	imxustop, imxutty, imxupoll, nommap, ttykqfilter, D_TTY
344 };
345 
346 /*
347  * Make this an option variable one can patch.
348  * But be warned:  this must be a power of 2!
349  */
350 u_int imxuart_rbuf_size = IMXUART_RING_SIZE;
351 
352 /* Stop input when 3/4 of the ring is full; restart when only 1/4 is full. */
353 u_int imxuart_rbuf_hiwat = (IMXUART_RING_SIZE * 1) / 4;
354 u_int imxuart_rbuf_lowat = (IMXUART_RING_SIZE * 3) / 4;
355 
356 static struct imxuart_regs imxuconsregs;
357 static int imxuconsattached;
358 static int imxuconsrate;
359 static tcflag_t imxuconscflag;
360 static struct cnm_state imxuart_cnm_state;
361 
362 u_int imxuart_freq = IMXUART_FREQ;
363 u_int imxuart_freqdiv = IMXUART_FREQDIV;
364 
365 #ifdef KGDB
366 #include <sys/kgdb.h>
367 
368 static struct imxuart_regs imxu_kgdb_regs;
369 static int imxu_kgdb_attached;
370 
371 int	imxuart_kgdb_getc(void *);
372 void	imxuart_kgdb_putc(void *, int);
373 #endif /* KGDB */
374 
375 #define	IMXUART_UNIT_MASK	0x7ffff
376 #define	IMXUART_DIALOUT_MASK	0x80000
377 
378 #define	IMXUART_UNIT(x)	(minor(x) & IMXUART_UNIT_MASK)
379 #define	IMXUART_DIALOUT(x)	(minor(x) & IMXUART_DIALOUT_MASK)
380 
381 #define	IMXUART_ISALIVE(sc)	((sc)->enabled != 0 && \
382 			 device_is_active((sc)->sc_dev))
383 
384 #define	BR	BUS_SPACE_BARRIER_READ
385 #define	BW	BUS_SPACE_BARRIER_WRITE
386 #define	IMXUART_BARRIER(r, f) \
387 	bus_space_barrier((r)->ur_iot, (r)->ur_ioh, 0, IMX_UART_SIZE, (f))
388 
389 
390 void
391 imxuart_attach_common(device_t parent, device_t self,
392     bus_space_tag_t iot, paddr_t iobase, size_t size, int intr, int flags)
393 {
394 	imxuart_softc_t *sc = device_private(self);
395 	struct imxuart_regs *regsp = &sc->sc_regs;
396 	struct tty *tp;
397 	bus_space_handle_t ioh;
398 
399 	aprint_naive("\n");
400 	aprint_normal("\n");
401 
402 	sc->sc_dev = self;
403 
404 	if (size <= 0)
405 		size = IMX_UART_SIZE;
406 
407 	sc->sc_intr = intr;
408 	regsp->ur_iot = iot;
409 	regsp->ur_iobase = iobase;
410 
411 	if (bus_space_map(iot, regsp->ur_iobase, size, 0, &ioh)) {
412 		return;
413 	}
414 	regsp->ur_ioh = ioh;
415 
416 	callout_init(&sc->sc_diag_callout, 0);
417 	mutex_init(&sc->sc_lock, MUTEX_DEFAULT, IPL_HIGH);
418 
419 	bus_space_read_region_4(iot, ioh, IMX_UCR1, sc->sc_ucr, 4);
420 	sc->sc_ucr2_d = sc->sc_ucr2;
421 
422 	/* Disable interrupts before configuring the device. */
423 	imxuart_disable_all_interrupts(sc);
424 
425 	if (regsp->ur_iobase == imxuconsregs.ur_iobase) {
426 		imxuconsattached = 1;
427 
428 		/* Make sure the console is always "hardwired". */
429 #if 0
430 		delay(10000);			/* wait for output to finish */
431 #endif
432 		SET(sc->sc_hwflags, IMXUART_HW_CONSOLE);
433 		SET(sc->sc_swflags, TIOCFLAG_SOFTCAR);
434 	}
435 
436 
437 	tp = ttymalloc();
438 	tp->t_oproc = imxustart;
439 	tp->t_param = imxuparam;
440 	tp->t_hwiflow = imxuhwiflow;
441 
442 	sc->sc_tty = tp;
443 	sc->sc_rbuf = malloc(sizeof (*sc->sc_rbuf) * imxuart_rbuf_size,
444 	    M_DEVBUF, M_NOWAIT);
445 	sc->sc_rbuf_size = imxuart_rbuf_size;
446 	sc->sc_rbuf_in = sc->sc_rbuf_out = 0;
447 	if (sc->sc_rbuf == NULL) {
448 		aprint_error_dev(sc->sc_dev,
449 		    "unable to allocate ring buffer\n");
450 		return;
451 	}
452 
453 	sc->sc_txfifo_len = 32;
454 	sc->sc_txfifo_thresh = 16;	/* when USR1.TRDY, fifo has space
455 					 * for this many characters */
456 
457 	tty_attach(tp);
458 
459 	if (ISSET(sc->sc_hwflags, IMXUART_HW_CONSOLE)) {
460 		int maj;
461 
462 		/* locate the major number */
463 		maj = cdevsw_lookup_major(&imxcom_cdevsw);
464 
465 		if (maj != NODEVMAJOR) {
466 			tp->t_dev = cn_tab->cn_dev = makedev(maj,
467 			    device_unit(sc->sc_dev));
468 
469 			aprint_normal_dev(sc->sc_dev, "console\n");
470 		}
471 	}
472 
473 	sc->sc_ih = intr_establish(sc->sc_intr, IPL_SERIAL, IST_LEVEL,
474 	    imxuintr, sc);
475 	if (sc->sc_ih == NULL)
476 		aprint_error_dev(sc->sc_dev, "intr_establish failed\n");
477 
478 #ifdef KGDB
479 	/*
480 	 * Allow kgdb to "take over" this port.  If this is
481 	 * not the console and is the kgdb device, it has
482 	 * exclusive use.  If it's the console _and_ the
483 	 * kgdb device, it doesn't.
484 	 */
485 	if (regsp->ur_iobase == imxu_kgdb_regs.ur_iobase) {
486 		if (!ISSET(sc->sc_hwflags, IMXUART_HW_CONSOLE)) {
487 			imxu_kgdb_attached = 1;
488 
489 			SET(sc->sc_hwflags, IMXUART_HW_KGDB);
490 		}
491 		aprint_normal_dev(sc->sc_dev, "kgdb\n");
492 	}
493 #endif
494 
495 	sc->sc_si = softint_establish(SOFTINT_SERIAL, imxusoft, sc);
496 
497 #if NRND > 0 && defined(RND_IMXUART)
498 	rnd_attach_source(&sc->rnd_source, device_xname(sc->sc_dev),
499 			  RND_TYPE_TTY, 0);
500 #endif
501 
502 	/* if there are no enable/disable functions, assume the device
503 	   is always enabled */
504 	if (!sc->enable)
505 		sc->enabled = 1;
506 
507 	imxuart_enable_debugport(sc);
508 
509 	SET(sc->sc_hwflags, IMXUART_HW_DEV_OK);
510 
511 	//shutdownhook_establish(imxuart_shutdownhook, sc);
512 
513 
514 #if 0
515 	{
516 		uint32_t reg;
517 		reg = bus_space_read_4(iot, ioh, IMX_UCR1);
518 		reg |= IMX_UCR1_TXDMAEN | IMX_UCR1_RXDMAEN;
519 		bus_space_write_4(iot, ioh, IMX_UCR1, reg);
520 	}
521 #endif
522 }
523 
524 /*
525  * baudrate = RefFreq / (16 * (UMBR + 1)/(UBIR + 1))
526  *
527  * (UBIR + 1) / (UBMR + 1) = (16 * BaurdRate) / RefFreq
528  */
529 
530 static long
531 gcd(long m, long n)
532 {
533 
534 	if (m < n)
535 		return gcd(n, m);
536 
537 	if (n <= 0)
538 		return m;
539 	return gcd(n, m % n);
540 }
541 
542 
543 int
544 imxuspeed(long speed, struct imxuart_baudrate_ratio *ratio)
545 {
546 #define	divrnd(n, q)	(((n)*2/(q)+1)/2)	/* divide and round off */
547 	long b = 16 * speed;
548 	long f = imxuart_freq / imxuart_freqdiv;
549 	long d;
550 	int err = 0;
551 
552 	/* reduce b/f */
553 	while ((f > (1<<16) || b > (1<<16)) && (d = gcd(f, b)) > 1) {
554 		f /= d;
555 		b /= d;
556 	}
557 
558 
559 	while (f > (1<<16) || b > (1<<16)) {
560 		f /= 2;
561 		b /= 2;
562 	}
563 	if (f <= 0 || b <= 0)
564 		return -1;
565 
566 #ifdef	DIAGNOSTIC
567 	err = divrnd(((uint64_t)imxuart_freq) * 1000 / imxuart_freqdiv,
568 		     (uint64_t)speed * 16 * f / b) - 1000;
569 	if (err < 0)
570 		err = -err;
571 #endif
572 
573 	ratio->numerator = b-1;
574 	ratio->modulator = f-1;
575 
576 	if (err > IMXUART_TOLERANCE)
577 		return -1;
578 
579 	return 0;
580 #undef	divrnd
581 }
582 
583 #ifdef IMXUART_DEBUG
584 int	imxuart_debug = 0;
585 
586 void imxustatus(struct imxuart_softc *, const char *);
587 void
588 imxustatus(struct imxuart_softc *sc, const char *str)
589 {
590 	struct tty *tp = sc->sc_tty;
591 
592 	aprint_normal_dev(sc->sc_dev,
593 	    "%s %cclocal  %cdcd %cts_carr_on %cdtr %ctx_stopped\n",
594 	    str,
595 	    ISSET(tp->t_cflag, CLOCAL) ? '+' : '-',
596 	    ISSET(sc->sc_msr, MSR_DCD) ? '+' : '-',
597 	    ISSET(tp->t_state, TS_CARR_ON) ? '+' : '-',
598 	    ISSET(sc->sc_mcr, MCR_DTR) ? '+' : '-',
599 	    sc->sc_tx_stopped ? '+' : '-');
600 
601 	aprint_normal_dev(sc->sc_dev,
602 	    "%s %ccrtscts %ccts %cts_ttstop  %crts rx_flags=0x%x\n",
603 	    str,
604 	    ISSET(tp->t_cflag, CRTSCTS) ? '+' : '-',
605 	    ISSET(sc->sc_msr, MSR_CTS) ? '+' : '-',
606 	    ISSET(tp->t_state, TS_TTSTOP) ? '+' : '-',
607 	    ISSET(sc->sc_mcr, MCR_RTS) ? '+' : '-',
608 	    sc->sc_rx_flags);
609 }
610 #endif
611 
612 #if 0
613 int
614 imxuart_detach(device_t self, int flags)
615 {
616 	struct imxuart_softc *sc = device_private(self);
617 	int maj, mn;
618 
619         if (ISSET(sc->sc_hwflags, IMXUART_HW_CONSOLE))
620 		return EBUSY;
621 
622 	/* locate the major number */
623 	maj = cdevsw_lookup_major(&imxcom_cdevsw);
624 
625 	/* Nuke the vnodes for any open instances. */
626 	mn = device_unit(self);
627 	vdevgone(maj, mn, mn, VCHR);
628 
629 	mn |= IMXUART_DIALOUT_MASK;
630 	vdevgone(maj, mn, mn, VCHR);
631 
632 	if (sc->sc_rbuf == NULL) {
633 		/*
634 		 * Ring buffer allocation failed in the imxuart_attach_subr,
635 		 * only the tty is allocated, and nothing else.
636 		 */
637 		ttyfree(sc->sc_tty);
638 		return 0;
639 	}
640 
641 	/* Free the receive buffer. */
642 	free(sc->sc_rbuf, M_DEVBUF);
643 
644 	/* Detach and free the tty. */
645 	tty_detach(sc->sc_tty);
646 	ttyfree(sc->sc_tty);
647 
648 	/* Unhook the soft interrupt handler. */
649 	softint_disestablish(sc->sc_si);
650 
651 #if NRND > 0 && defined(RND_IMXU)
652 	/* Unhook the entropy source. */
653 	rnd_detach_source(&sc->rnd_source);
654 #endif
655 	callout_destroy(&sc->sc_diag_callout);
656 
657 	/* Destroy the lock. */
658 	mutex_destroy(&sc->sc_lock);
659 
660 	return (0);
661 }
662 #endif
663 
664 #ifdef notyet
665 int
666 imxuart_activate(device_t self, enum devact act)
667 {
668 	struct imxuart_softc *sc = device_private(self);
669 	int rv = 0;
670 
671 	switch (act) {
672 	case DVACT_ACTIVATE:
673 		rv = EOPNOTSUPP;
674 		break;
675 
676 	case DVACT_DEACTIVATE:
677 		if (sc->sc_hwflags & (IMXUART_HW_CONSOLE|IMXUART_HW_KGDB)) {
678 			rv = EBUSY;
679 			break;
680 		}
681 
682 		if (sc->disable != NULL && sc->enabled != 0) {
683 			(*sc->disable)(sc);
684 			sc->enabled = 0;
685 		}
686 		break;
687 	}
688 
689 	return (rv);
690 }
691 #endif
692 
693 void
694 imxuart_shutdown(struct imxuart_softc *sc)
695 {
696 	struct tty *tp = sc->sc_tty;
697 
698 	mutex_spin_enter(&sc->sc_lock);
699 
700 	/* If we were asserting flow control, then deassert it. */
701 	SET(sc->sc_rx_flags, IMXUART_RX_IBUF_BLOCKED);
702 	imxuart_hwiflow(sc);
703 
704 	/* Clear any break condition set with TIOCSBRK. */
705 	imxuart_break(sc, false);
706 
707 	/*
708 	 * Hang up if necessary.  Wait a bit, so the other side has time to
709 	 * notice even if we immediately open the port again.
710 	 * Avoid tsleeping above splhigh().
711 	 */
712 	if (ISSET(tp->t_cflag, HUPCL)) {
713 		imxuart_modem(sc, 0);
714 		mutex_spin_exit(&sc->sc_lock);
715 		/* XXX will only timeout */
716 		(void) kpause(ttclos, false, hz, NULL);
717 		mutex_spin_enter(&sc->sc_lock);
718 	}
719 
720 	/* Turn off interrupts. */
721 	imxuart_disable_all_interrupts(sc);
722 	/* re-enable recv interrupt for console or kgdb port */
723 	imxuart_enable_debugport(sc);
724 
725 	mutex_spin_exit(&sc->sc_lock);
726 
727 #ifdef	notyet
728 	if (sc->disable) {
729 #ifdef DIAGNOSTIC
730 		if (!sc->enabled)
731 			panic("imxuart_shutdown: not enabled?");
732 #endif
733 		(*sc->disable)(sc);
734 		sc->enabled = 0;
735 	}
736 #endif
737 }
738 
739 int
740 imxuopen(dev_t dev, int flag, int mode, struct lwp *l)
741 {
742 	struct imxuart_softc *sc;
743 	struct tty *tp;
744 	int s;
745 	int error;
746 
747 	sc = device_lookup_private(&imxuart_cd, IMXUART_UNIT(dev));
748 	if (sc == NULL || !ISSET(sc->sc_hwflags, IMXUART_HW_DEV_OK) ||
749 		sc->sc_rbuf == NULL)
750 		return (ENXIO);
751 
752 	if (!device_is_active(sc->sc_dev))
753 		return (ENXIO);
754 
755 #ifdef KGDB
756 	/*
757 	 * If this is the kgdb port, no other use is permitted.
758 	 */
759 	if (ISSET(sc->sc_hwflags, IMXUART_HW_KGDB))
760 		return (EBUSY);
761 #endif
762 
763 	tp = sc->sc_tty;
764 
765 	if (kauth_authorize_device_tty(l->l_cred, KAUTH_DEVICE_TTY_OPEN, tp))
766 		return (EBUSY);
767 
768 	s = spltty();
769 
770 	/*
771 	 * Do the following iff this is a first open.
772 	 */
773 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
774 		struct termios t;
775 
776 		tp->t_dev = dev;
777 
778 
779 #ifdef notyet
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 			sc->enabled = 1;
788 		}
789 #endif
790 
791 		mutex_spin_enter(&sc->sc_lock);
792 
793 		imxuart_disable_all_interrupts(sc);
794 
795 		/* Fetch the current modem control status, needed later. */
796 
797 #ifdef	IMXUART_PPS
798 		/* Clear PPS capture state on first open. */
799 		mutex_spin_enter(&timecounter_lock);
800 		memset(&sc->sc_pps_state, 0, sizeof(sc->sc_pps_state));
801 		sc->sc_pps_state.ppscap = PPS_CAPTUREASSERT | PPS_CAPTURECLEAR;
802 		pps_init(&sc->sc_pps_state);
803 		mutex_spin_exit(&timecounter_lock);
804 #endif
805 
806 		mutex_spin_exit(&sc->sc_lock);
807 
808 		/*
809 		 * Initialize the termios status to the defaults.  Add in the
810 		 * sticky bits from TIOCSFLAGS.
811 		 */
812 		if (ISSET(sc->sc_hwflags, IMXUART_HW_CONSOLE)) {
813 			t.c_ospeed = imxuconsrate;
814 			t.c_cflag = imxuconscflag;
815 		} else {
816 			t.c_ospeed = TTYDEF_SPEED;
817 			t.c_cflag = TTYDEF_CFLAG;
818 		}
819 		t.c_ispeed = t.c_ospeed;
820 		if (ISSET(sc->sc_swflags, TIOCFLAG_CLOCAL))
821 			SET(t.c_cflag, CLOCAL);
822 		if (ISSET(sc->sc_swflags, TIOCFLAG_CRTSCTS))
823 			SET(t.c_cflag, CRTSCTS);
824 		if (ISSET(sc->sc_swflags, TIOCFLAG_MDMBUF))
825 			SET(t.c_cflag, MDMBUF);
826 		/* Make sure imxuparam() will do something. */
827 		tp->t_ospeed = 0;
828 		(void) imxuparam(tp, &t);
829 		tp->t_iflag = TTYDEF_IFLAG;
830 		tp->t_oflag = TTYDEF_OFLAG;
831 		tp->t_lflag = TTYDEF_LFLAG;
832 		ttychars(tp);
833 		ttsetwater(tp);
834 
835 		mutex_spin_enter(&sc->sc_lock);
836 
837 		/*
838 		 * Turn on DTR.  We must always do this, even if carrier is not
839 		 * present, because otherwise we'd have to use TIOCSDTR
840 		 * immediately after setting CLOCAL, which applications do not
841 		 * expect.  We always assert DTR while the device is open
842 		 * unless explicitly requested to deassert it.
843 		 */
844 		imxuart_modem(sc, 1);
845 
846 		/* Clear the input ring, and unblock. */
847 		sc->sc_rbuf_in = sc->sc_rbuf_out = 0;
848 		imxuart_iflush(sc);
849 		CLR(sc->sc_rx_flags, IMXUART_RX_ANY_BLOCK);
850 		imxuart_hwiflow(sc);
851 
852 		/* Turn on interrupts. */
853 		imxuart_control_rxint(sc, true);
854 
855 #ifdef IMXUART_DEBUG
856 		if (imxuart_debug)
857 			imxustatus(sc, "imxuopen  ");
858 #endif
859 
860 		mutex_spin_exit(&sc->sc_lock);
861 	}
862 
863 	splx(s);
864 
865 #if 0
866 	error = ttyopen(tp, IMXUART_DIALOUT(dev), ISSET(flag, O_NONBLOCK));
867 #else
868 	error = ttyopen(tp, 1, ISSET(flag, O_NONBLOCK));
869 #endif
870 	if (error)
871 		goto bad;
872 
873 	error = (*tp->t_linesw->l_open)(dev, tp);
874 	if (error)
875 		goto bad;
876 
877 	return (0);
878 
879 bad:
880 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
881 		/*
882 		 * We failed to open the device, and nobody else had it opened.
883 		 * Clean up the state as appropriate.
884 		 */
885 		imxuart_shutdown(sc);
886 	}
887 
888 	return (error);
889 }
890 
891 int
892 imxuclose(dev_t dev, int flag, int mode, struct lwp *l)
893 {
894 	struct imxuart_softc *sc =
895 	    device_lookup_private(&imxuart_cd, IMXUART_UNIT(dev));
896 	struct tty *tp = sc->sc_tty;
897 
898 	/* XXX This is for cons.c. */
899 	if (!ISSET(tp->t_state, TS_ISOPEN))
900 		return (0);
901 
902 	(*tp->t_linesw->l_close)(tp, flag);
903 	ttyclose(tp);
904 
905 	if (IMXUART_ISALIVE(sc) == 0)
906 		return (0);
907 
908 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
909 		/*
910 		 * Although we got a last close, the device may still be in
911 		 * use; e.g. if this was the dialout node, and there are still
912 		 * processes waiting for carrier on the non-dialout node.
913 		 */
914 		imxuart_shutdown(sc);
915 	}
916 
917 	return (0);
918 }
919 
920 int
921 imxuread(dev_t dev, struct uio *uio, int flag)
922 {
923 	struct imxuart_softc *sc =
924 	    device_lookup_private(&imxuart_cd, IMXUART_UNIT(dev));
925 	struct tty *tp = sc->sc_tty;
926 
927 	if (IMXUART_ISALIVE(sc) == 0)
928 		return (EIO);
929 
930 	return ((*tp->t_linesw->l_read)(tp, uio, flag));
931 }
932 
933 int
934 imxuwrite(dev_t dev, struct uio *uio, int flag)
935 {
936 	struct imxuart_softc *sc =
937 	    device_lookup_private(&imxuart_cd, IMXUART_UNIT(dev));
938 	struct tty *tp = sc->sc_tty;
939 
940 	if (IMXUART_ISALIVE(sc) == 0)
941 		return (EIO);
942 
943 	return ((*tp->t_linesw->l_write)(tp, uio, flag));
944 }
945 
946 int
947 imxupoll(dev_t dev, int events, struct lwp *l)
948 {
949 	struct imxuart_softc *sc =
950 	    device_lookup_private(&imxuart_cd, IMXUART_UNIT(dev));
951 	struct tty *tp = sc->sc_tty;
952 
953 	if (IMXUART_ISALIVE(sc) == 0)
954 		return (POLLHUP);
955 
956 	return ((*tp->t_linesw->l_poll)(tp, events, l));
957 }
958 
959 struct tty *
960 imxutty(dev_t dev)
961 {
962 	struct imxuart_softc *sc =
963 	    device_lookup_private(&imxuart_cd, IMXUART_UNIT(dev));
964 	struct tty *tp = sc->sc_tty;
965 
966 	return (tp);
967 }
968 
969 int
970 imxuioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l)
971 {
972 	struct imxuart_softc *sc;
973 	struct tty *tp;
974 	int error;
975 
976 	sc = device_lookup_private(&imxuart_cd, IMXUART_UNIT(dev));
977 	if (sc == NULL)
978 		return ENXIO;
979 	if (IMXUART_ISALIVE(sc) == 0)
980 		return (EIO);
981 
982 	tp = sc->sc_tty;
983 
984 	error = (*tp->t_linesw->l_ioctl)(tp, cmd, data, flag, l);
985 	if (error != EPASSTHROUGH)
986 		return (error);
987 
988 	error = ttioctl(tp, cmd, data, flag, l);
989 	if (error != EPASSTHROUGH)
990 		return (error);
991 
992 	error = 0;
993 	switch (cmd) {
994 	case TIOCSFLAGS:
995 		error = kauth_authorize_device_tty(l->l_cred,
996 		    KAUTH_DEVICE_TTY_PRIVSET, tp);
997 		break;
998 	default:
999 		/* nothing */
1000 		break;
1001 	}
1002 	if (error) {
1003 		return error;
1004 	}
1005 
1006 	mutex_spin_enter(&sc->sc_lock);
1007 
1008 	switch (cmd) {
1009 	case TIOCSBRK:
1010 		imxuart_break(sc, true);
1011 		break;
1012 
1013 	case TIOCCBRK:
1014 		imxuart_break(sc, false);
1015 		break;
1016 
1017 	case TIOCSDTR:
1018 		imxuart_modem(sc, 1);
1019 		break;
1020 
1021 	case TIOCCDTR:
1022 		imxuart_modem(sc, 0);
1023 		break;
1024 
1025 	case TIOCGFLAGS:
1026 		*(int *)data = sc->sc_swflags;
1027 		break;
1028 
1029 	case TIOCSFLAGS:
1030 		sc->sc_swflags = *(int *)data;
1031 		break;
1032 
1033 	case TIOCMSET:
1034 	case TIOCMBIS:
1035 	case TIOCMBIC:
1036 		tiocm_to_imxu(sc, cmd, *(int *)data);
1037 		break;
1038 
1039 	case TIOCMGET:
1040 		*(int *)data = imxuart_to_tiocm(sc);
1041 		break;
1042 
1043 #ifdef notyet
1044 	case PPS_IOC_CREATE:
1045 	case PPS_IOC_DESTROY:
1046 	case PPS_IOC_GETPARAMS:
1047 	case PPS_IOC_SETPARAMS:
1048 	case PPS_IOC_GETCAP:
1049 	case PPS_IOC_FETCH:
1050 #ifdef PPS_SYNC
1051 	case PPS_IOC_KCBIND:
1052 #endif
1053 		mutex_spin_enter(&timecounter_lock);
1054 		error = pps_ioctl(cmd, data, &sc->sc_pps_state);
1055 		mutex_spin_exit(&timecounter_lock);
1056 		break;
1057 
1058 	case TIOCDCDTIMESTAMP:	/* XXX old, overloaded  API used by xntpd v3 */
1059 		mutex_spin_enter(&timecounter_lock);
1060 #ifndef PPS_TRAILING_EDGE
1061 		TIMESPEC_TO_TIMEVAL((struct timeval *)data,
1062 		    &sc->sc_pps_state.ppsinfo.assert_timestamp);
1063 #else
1064 		TIMESPEC_TO_TIMEVAL((struct timeval *)data,
1065 		    &sc->sc_pps_state.ppsinfo.clear_timestamp);
1066 #endif
1067 		mutex_spin_exit(&timecounter_lock);
1068 		break;
1069 #endif
1070 
1071 	default:
1072 		error = EPASSTHROUGH;
1073 		break;
1074 	}
1075 
1076 	mutex_spin_exit(&sc->sc_lock);
1077 
1078 #ifdef IMXUART_DEBUG
1079 	if (imxuart_debug)
1080 		imxustatus(sc, "imxuioctl ");
1081 #endif
1082 
1083 	return (error);
1084 }
1085 
1086 integrate void
1087 imxuart_schedrx(struct imxuart_softc *sc)
1088 {
1089 	sc->sc_rx_ready = 1;
1090 
1091 	/* Wake up the poller. */
1092 	softint_schedule(sc->sc_si);
1093 }
1094 
1095 void
1096 imxuart_break(struct imxuart_softc *sc, bool onoff)
1097 {
1098 	bus_space_tag_t iot = sc->sc_regs.ur_iot;
1099 	bus_space_handle_t ioh = sc->sc_regs.ur_ioh;
1100 
1101 	if (onoff)
1102 		SET(sc->sc_ucr1, IMX_UCR1_SNDBRK);
1103 	else
1104 		CLR(sc->sc_ucr1, IMX_UCR1_SNDBRK);
1105 
1106 	bus_space_write_4(iot, ioh, IMX_UCR1, sc->sc_ucr1);
1107 }
1108 
1109 void
1110 imxuart_modem(struct imxuart_softc *sc, int onoff)
1111 {
1112 #ifdef notyet
1113 	if (sc->sc_mcr_dtr == 0)
1114 		return;
1115 
1116 	if (onoff)
1117 		SET(sc->sc_mcr, sc->sc_mcr_dtr);
1118 	else
1119 		CLR(sc->sc_mcr, sc->sc_mcr_dtr);
1120 
1121 	if (!sc->sc_heldchange) {
1122 		if (sc->sc_tx_busy) {
1123 			sc->sc_heldtbc = sc->sc_tbc;
1124 			sc->sc_tbc = 0;
1125 			sc->sc_heldchange = 1;
1126 		} else
1127 			imxuart_loadchannelregs(sc);
1128 	}
1129 #endif
1130 }
1131 
1132 /*
1133  * RTS output is controlled by UCR2.CTS bit.
1134  * DTR output is controlled by UCR3.DSR bit.
1135  * (i.MX reference manual uses names in DCE mode)
1136  *
1137  * note: if UCR2.CTSC == 1 for automatic HW flow control, UCR2.CTS is ignored.
1138  */
1139 void
1140 tiocm_to_imxu(struct imxuart_softc *sc, u_long how, int ttybits)
1141 {
1142 	bus_space_tag_t iot = sc->sc_regs.ur_iot;
1143 	bus_space_handle_t ioh = sc->sc_regs.ur_ioh;
1144 
1145 	uint32_t ucr2 = sc->sc_ucr2_d;
1146 	uint32_t ucr3 = sc->sc_ucr3;
1147 
1148 	uint32_t ucr2_mask = 0;
1149 	uint32_t ucr3_mask = 0;
1150 
1151 
1152 	if (ISSET(ttybits, TIOCM_DTR))
1153 		ucr3_mask = IMX_UCR3_DSR;
1154 	if (ISSET(ttybits, TIOCM_RTS))
1155 		ucr2_mask = IMX_UCR2_CTS;
1156 
1157 	switch (how) {
1158 	case TIOCMBIC:
1159 		CLR(ucr2, ucr2_mask);
1160 		CLR(ucr3, ucr3_mask);
1161 		break;
1162 
1163 	case TIOCMBIS:
1164 		SET(ucr2, ucr2_mask);
1165 		SET(ucr3, ucr3_mask);
1166 		break;
1167 
1168 	case TIOCMSET:
1169 		CLR(ucr2, ucr2_mask);
1170 		CLR(ucr3, ucr3_mask);
1171 		SET(ucr2, ucr2_mask);
1172 		SET(ucr3, ucr3_mask);
1173 		break;
1174 	}
1175 
1176 	if (ucr3 != sc->sc_ucr3) {
1177 		bus_space_write_4(iot, ioh, IMX_UCR3, ucr3);
1178 		sc->sc_ucr3 = ucr3;
1179 	}
1180 
1181 	if (ucr2 == sc->sc_ucr2_d)
1182 		return;
1183 
1184 	sc->sc_ucr2_d = ucr2;
1185 	/* update CTS bit only */
1186 	ucr2 = (sc->sc_ucr2 & ~IMX_UCR2_CTS) |
1187 	    (ucr2 & IMX_UCR2_CTS);
1188 
1189 	bus_space_write_4(iot, ioh, IMX_UCR2, ucr2);
1190 	sc->sc_ucr2 = ucr2;
1191 }
1192 
1193 int
1194 imxuart_to_tiocm(struct imxuart_softc *sc)
1195 {
1196 	bus_space_tag_t iot = sc->sc_regs.ur_iot;
1197 	bus_space_handle_t ioh = sc->sc_regs.ur_ioh;
1198 	int ttybits = 0;
1199 	uint32_t usr[2];
1200 
1201 	if (ISSET(sc->sc_ucr3, IMX_UCR3_DSR))
1202 		SET(ttybits, TIOCM_DTR);
1203 	if (ISSET(sc->sc_ucr2, IMX_UCR2_CTS))
1204 		SET(ttybits, TIOCM_RTS);
1205 
1206 	bus_space_read_region_4(iot, ioh, IMX_USR1, usr, 2);
1207 
1208 	if (ISSET(usr[0], IMX_USR1_RTSS))
1209 		SET(ttybits, TIOCM_CTS);
1210 
1211 	if (ISSET(usr[1], IMX_USR2_DCDIN))
1212 		SET(ttybits, TIOCM_CD);
1213 
1214 #if 0
1215 	/* XXXbsh: I couldn't find the way to read ipp_uart_dsr_dte_i signal,
1216 	   although there are bits in UART registers to detect delta of DSR.
1217 	*/
1218 	if (ISSET(imxubits, MSR_DSR))
1219 		SET(ttybits, TIOCM_DSR);
1220 #endif
1221 
1222 	if (ISSET(usr[1], IMX_USR2_RIIN))
1223 		SET(ttybits, TIOCM_RI);
1224 
1225 
1226 #ifdef	notyet
1227 	if (ISSET(sc->sc_ier, IER_ERXRDY | IER_ETXRDY | IER_ERLS | IER_EMSC))
1228 		SET(ttybits, TIOCM_LE);
1229 #endif
1230 
1231 	return (ttybits);
1232 }
1233 
1234 static uint32_t
1235 cflag_to_ucr2(tcflag_t cflag, uint32_t oldval)
1236 {
1237 	uint32_t val = oldval;
1238 
1239 	CLR(val,IMX_UCR2_WS|IMX_UCR2_PREN|IMX_UCR2_PROE|IMX_UCR2_STPB);
1240 
1241 	switch (cflag & CSIZE) {
1242 	case CS5:
1243 	case CS6:
1244 		/* not suppreted. use 7-bits */
1245 	case CS7:
1246 		break;
1247 	case CS8:
1248 		SET(val, IMX_UCR2_WS);
1249 		break;
1250 	}
1251 
1252 
1253 	if (ISSET(cflag, PARENB)) {
1254 		SET(val, IMX_UCR2_PREN);
1255 
1256 		/* odd parity */
1257 		if (!ISSET(cflag, PARODD))
1258 			SET(val, IMX_UCR2_PROE);
1259 	}
1260 
1261 	if (ISSET(cflag, CSTOPB))
1262 		SET(val, IMX_UCR2_STPB);
1263 
1264 	val |= IMX_UCR2_TXEN| IMX_UCR2_RXEN|IMX_UCR2_SRST;
1265 
1266 	return val;
1267 }
1268 
1269 int
1270 imxuparam(struct tty *tp, struct termios *t)
1271 {
1272 	struct imxuart_softc *sc =
1273 	    device_lookup_private(&imxuart_cd, IMXUART_UNIT(tp->t_dev));
1274 	struct imxuart_baudrate_ratio ratio;
1275 	uint32_t ucr2;
1276 	bool change_speed = tp->t_ospeed != t->c_ospeed;
1277 
1278 	if (IMXUART_ISALIVE(sc) == 0)
1279 		return (EIO);
1280 
1281 	/* Check requested parameters. */
1282 	if (t->c_ispeed && t->c_ispeed != t->c_ospeed)
1283 		return (EINVAL);
1284 
1285 	/*
1286 	 * For the console, always force CLOCAL and !HUPCL, so that the port
1287 	 * is always active.
1288 	 */
1289 	if (ISSET(sc->sc_swflags, TIOCFLAG_SOFTCAR) ||
1290 	    ISSET(sc->sc_hwflags, IMXUART_HW_CONSOLE)) {
1291 		SET(t->c_cflag, CLOCAL);
1292 		CLR(t->c_cflag, HUPCL);
1293 	}
1294 
1295 	/*
1296 	 * If there were no changes, don't do anything.  This avoids dropping
1297 	 * input and improves performance when all we did was frob things like
1298 	 * VMIN and VTIME.
1299 	 */
1300 	if ( !change_speed && tp->t_cflag == t->c_cflag)
1301 		return (0);
1302 
1303 	if (change_speed) {
1304 		/* calculate baudrate modulator value */
1305 		if (imxuspeed(t->c_ospeed, &ratio) < 0)
1306 			return (EINVAL);
1307 		sc->sc_ratio = ratio;
1308 	}
1309 
1310 	ucr2 = cflag_to_ucr2(t->c_cflag, sc->sc_ucr2_d);
1311 
1312 	mutex_spin_enter(&sc->sc_lock);
1313 
1314 #if 0	/* flow control stuff.  not yet */
1315 	/*
1316 	 * If we're not in a mode that assumes a connection is present, then
1317 	 * ignore carrier changes.
1318 	 */
1319 	if (ISSET(t->c_cflag, CLOCAL | MDMBUF))
1320 		sc->sc_msr_dcd = 0;
1321 	else
1322 		sc->sc_msr_dcd = MSR_DCD;
1323 	/*
1324 	 * Set the flow control pins depending on the current flow control
1325 	 * mode.
1326 	 */
1327 	if (ISSET(t->c_cflag, CRTSCTS)) {
1328 		sc->sc_mcr_dtr = MCR_DTR;
1329 		sc->sc_mcr_rts = MCR_RTS;
1330 		sc->sc_msr_cts = MSR_CTS;
1331 		sc->sc_efr = EFR_AUTORTS | EFR_AUTOCTS;
1332 	} else if (ISSET(t->c_cflag, MDMBUF)) {
1333 		/*
1334 		 * For DTR/DCD flow control, make sure we don't toggle DTR for
1335 		 * carrier detection.
1336 		 */
1337 		sc->sc_mcr_dtr = 0;
1338 		sc->sc_mcr_rts = MCR_DTR;
1339 		sc->sc_msr_cts = MSR_DCD;
1340 		sc->sc_efr = 0;
1341 	} else {
1342 		/*
1343 		 * If no flow control, then always set RTS.  This will make
1344 		 * the other side happy if it mistakenly thinks we're doing
1345 		 * RTS/CTS flow control.
1346 		 */
1347 		sc->sc_mcr_dtr = MCR_DTR | MCR_RTS;
1348 		sc->sc_mcr_rts = 0;
1349 		sc->sc_msr_cts = 0;
1350 		sc->sc_efr = 0;
1351 		if (ISSET(sc->sc_mcr, MCR_DTR))
1352 			SET(sc->sc_mcr, MCR_RTS);
1353 		else
1354 			CLR(sc->sc_mcr, MCR_RTS);
1355 	}
1356 	sc->sc_msr_mask = sc->sc_msr_cts | sc->sc_msr_dcd;
1357 #endif
1358 
1359 	/* And copy to tty. */
1360 	tp->t_ispeed = t->c_ospeed;
1361 	tp->t_ospeed = t->c_ospeed;
1362 	tp->t_cflag = t->c_cflag;
1363 
1364 	if (!change_speed && ucr2 == sc->sc_ucr2_d) {
1365 		/* noop */
1366 	}
1367 	else if (!sc->sc_pending && !sc->sc_tx_busy) {
1368 		if (ucr2 != sc->sc_ucr2_d) {
1369 			sc->sc_ucr2_d = ucr2;
1370 			imxuart_load_params(sc);
1371 		}
1372 		if (change_speed)
1373 			imxuart_load_speed(sc);
1374 	}
1375 	else {
1376 		if (!sc->sc_pending) {
1377 			sc->sc_heldtbc = sc->sc_tbc;
1378 			sc->sc_tbc = 0;
1379 		}
1380 		sc->sc_pending |=
1381 		    (ucr2 == sc->sc_ucr2_d ? 0 : IMXUART_PEND_PARAM) |
1382 		    (change_speed ? 0 : IMXUART_PEND_SPEED);
1383 		sc->sc_ucr2_d = ucr2;
1384 	}
1385 
1386 	if (!ISSET(t->c_cflag, CHWFLOW)) {
1387 		/* Disable the high water mark. */
1388 		sc->sc_r_hiwat = 0;
1389 		sc->sc_r_lowat = 0;
1390 		if (ISSET(sc->sc_rx_flags, IMXUART_RX_TTY_OVERFLOWED)) {
1391 			CLR(sc->sc_rx_flags, IMXUART_RX_TTY_OVERFLOWED);
1392 			imxuart_schedrx(sc);
1393 		}
1394 		if (ISSET(sc->sc_rx_flags,
1395 			IMXUART_RX_TTY_BLOCKED|IMXUART_RX_IBUF_BLOCKED)) {
1396 			CLR(sc->sc_rx_flags,
1397 			    IMXUART_RX_TTY_BLOCKED|IMXUART_RX_IBUF_BLOCKED);
1398 			imxuart_hwiflow(sc);
1399 		}
1400 	} else {
1401 		sc->sc_r_hiwat = imxuart_rbuf_hiwat;
1402 		sc->sc_r_lowat = imxuart_rbuf_lowat;
1403 	}
1404 
1405 	mutex_spin_exit(&sc->sc_lock);
1406 
1407 #if 0
1408 	/*
1409 	 * Update the tty layer's idea of the carrier bit, in case we changed
1410 	 * CLOCAL or MDMBUF.  We don't hang up here; we only do that by
1411 	 * explicit request.
1412 	 */
1413 	(void) (*tp->t_linesw->l_modem)(tp, ISSET(sc->sc_msr, MSR_DCD));
1414 #else
1415 	/* XXX: always report that we have DCD */
1416 	(void) (*tp->t_linesw->l_modem)(tp, 1);
1417 #endif
1418 
1419 #ifdef IMXUART_DEBUG
1420 	if (imxuart_debug)
1421 		imxustatus(sc, "imxuparam ");
1422 #endif
1423 
1424 	if (!ISSET(t->c_cflag, CHWFLOW)) {
1425 		if (sc->sc_tx_stopped) {
1426 			sc->sc_tx_stopped = 0;
1427 			imxustart(tp);
1428 		}
1429 	}
1430 
1431 	return (0);
1432 }
1433 
1434 void
1435 imxuart_iflush(struct imxuart_softc *sc)
1436 {
1437 	bus_space_tag_t iot = sc->sc_regs.ur_iot;
1438 	bus_space_handle_t ioh = sc->sc_regs.ur_ioh;
1439 #ifdef DIAGNOSTIC
1440 	uint32_t reg = 0xffff;
1441 #endif
1442 	int timo;
1443 
1444 	timo = 50000;
1445 	/* flush any pending I/O */
1446 	while (ISSET(bus_space_read_4(iot, ioh, IMX_USR2), IMX_USR2_RDR)
1447 	    && --timo)
1448 #ifdef DIAGNOSTIC
1449 		reg =
1450 #else
1451 		    (void)
1452 #endif
1453 		    bus_space_read_4(iot, ioh, IMX_URXD);
1454 #ifdef DIAGNOSTIC
1455 	if (!timo)
1456 		aprint_error_dev(sc->sc_dev, "imxuart_iflush timeout %02x\n", reg);
1457 #endif
1458 }
1459 
1460 int
1461 imxuhwiflow(struct tty *tp, int block)
1462 {
1463 	struct imxuart_softc *sc =
1464 	    device_lookup_private(&imxuart_cd, IMXUART_UNIT(tp->t_dev));
1465 
1466 	if (IMXUART_ISALIVE(sc) == 0)
1467 		return (0);
1468 
1469 #ifdef notyet
1470 	if (sc->sc_mcr_rts == 0)
1471 		return (0);
1472 #endif
1473 
1474 	mutex_spin_enter(&sc->sc_lock);
1475 
1476 	if (block) {
1477 		if (!ISSET(sc->sc_rx_flags, IMXUART_RX_TTY_BLOCKED)) {
1478 			SET(sc->sc_rx_flags, IMXUART_RX_TTY_BLOCKED);
1479 			imxuart_hwiflow(sc);
1480 		}
1481 	} else {
1482 		if (ISSET(sc->sc_rx_flags, IMXUART_RX_TTY_OVERFLOWED)) {
1483 			CLR(sc->sc_rx_flags, IMXUART_RX_TTY_OVERFLOWED);
1484 			imxuart_schedrx(sc);
1485 		}
1486 		if (ISSET(sc->sc_rx_flags, IMXUART_RX_TTY_BLOCKED)) {
1487 			CLR(sc->sc_rx_flags, IMXUART_RX_TTY_BLOCKED);
1488 			imxuart_hwiflow(sc);
1489 		}
1490 	}
1491 
1492 	mutex_spin_exit(&sc->sc_lock);
1493 	return (1);
1494 }
1495 
1496 /*
1497  * (un)block input via hw flowcontrol
1498  */
1499 void
1500 imxuart_hwiflow(struct imxuart_softc *sc)
1501 {
1502 #ifdef notyet
1503 	struct imxuart_regs *regsp= &sc->sc_regs;
1504 
1505 	if (sc->sc_mcr_rts == 0)
1506 		return;
1507 
1508 	if (ISSET(sc->sc_rx_flags, RX_ANY_BLOCK)) {
1509 		CLR(sc->sc_mcr, sc->sc_mcr_rts);
1510 		CLR(sc->sc_mcr_active, sc->sc_mcr_rts);
1511 	} else {
1512 		SET(sc->sc_mcr, sc->sc_mcr_rts);
1513 		SET(sc->sc_mcr_active, sc->sc_mcr_rts);
1514 	}
1515 	UR_WRITE_1(regsp, IMXUART_REG_MCR, sc->sc_mcr_active);
1516 #endif
1517 }
1518 
1519 
1520 void
1521 imxustart(struct tty *tp)
1522 {
1523 	struct imxuart_softc *sc =
1524 	    device_lookup_private(&imxuart_cd, IMXUART_UNIT(tp->t_dev));
1525 	int s;
1526 	u_char *tba;
1527 	int tbc;
1528 	u_int n;
1529 	u_int space;
1530 	bus_space_tag_t iot = sc->sc_regs.ur_iot;
1531 	bus_space_handle_t ioh = sc->sc_regs.ur_ioh;
1532 
1533 	if (IMXUART_ISALIVE(sc) == 0)
1534 		return;
1535 
1536 	s = spltty();
1537 	if (ISSET(tp->t_state, TS_BUSY | TS_TIMEOUT | TS_TTSTOP))
1538 		goto out;
1539 	if (sc->sc_tx_stopped)
1540 		goto out;
1541 	if (!ttypull(tp))
1542 		goto out;
1543 
1544 	/* Grab the first contiguous region of buffer space. */
1545 	tba = tp->t_outq.c_cf;
1546 	tbc = ndqb(&tp->t_outq, 0);
1547 
1548 	mutex_spin_enter(&sc->sc_lock);
1549 
1550 	sc->sc_tba = tba;
1551 	sc->sc_tbc = tbc;
1552 
1553 	SET(tp->t_state, TS_BUSY);
1554 	sc->sc_tx_busy = 1;
1555 
1556 	space = imxuart_txfifo_space(sc);
1557 	n = MIN(sc->sc_tbc, space);
1558 
1559 	bus_space_write_multi_1(iot, ioh, IMX_UTXD, sc->sc_tba, n);
1560 	sc->sc_tbc -= n;
1561 	sc->sc_tba += n;
1562 
1563 	/* Enable transmit completion interrupts */
1564 	imxuart_control_txint(sc, true);
1565 
1566 	mutex_spin_exit(&sc->sc_lock);
1567 out:
1568 	splx(s);
1569 	return;
1570 }
1571 
1572 /*
1573  * Stop output on a line.
1574  */
1575 void
1576 imxustop(struct tty *tp, int flag)
1577 {
1578 	struct imxuart_softc *sc =
1579 	    device_lookup_private(&imxuart_cd, IMXUART_UNIT(tp->t_dev));
1580 
1581 	mutex_spin_enter(&sc->sc_lock);
1582 	if (ISSET(tp->t_state, TS_BUSY)) {
1583 		/* Stop transmitting at the next chunk. */
1584 		sc->sc_tbc = 0;
1585 		sc->sc_heldtbc = 0;
1586 		if (!ISSET(tp->t_state, TS_TTSTOP))
1587 			SET(tp->t_state, TS_FLUSH);
1588 	}
1589 	mutex_spin_exit(&sc->sc_lock);
1590 }
1591 
1592 void
1593 imxudiag(void *arg)
1594 {
1595 #ifdef notyet
1596 	struct imxuart_softc *sc = arg;
1597 	int overflows, floods;
1598 
1599 	mutex_spin_enter(&sc->sc_lock);
1600 	overflows = sc->sc_overflows;
1601 	sc->sc_overflows = 0;
1602 	floods = sc->sc_floods;
1603 	sc->sc_floods = 0;
1604 	sc->sc_errors = 0;
1605 	mutex_spin_exit(&sc->sc_lock);
1606 
1607 	log(LOG_WARNING, "%s: %d silo overflow%s, %d ibuf flood%s\n",
1608 	    device_xname(sc->sc_dev),
1609 	    overflows, overflows == 1 ? "" : "s",
1610 	    floods, floods == 1 ? "" : "s");
1611 #endif
1612 }
1613 
1614 integrate void
1615 imxuart_rxsoft(struct imxuart_softc *sc, struct tty *tp)
1616 {
1617 	int (*rint)(int, struct tty *) = tp->t_linesw->l_rint;
1618 	u_int cc, scc, outp;
1619 	uint16_t data;
1620 	u_int code;
1621 
1622 	scc = cc = IMXUART_RBUF_AVAIL(sc);
1623 
1624 #if 0
1625 	if (cc == imxuart_rbuf_size-1) {
1626 		sc->sc_floods++;
1627 		if (sc->sc_errors++ == 0)
1628 			callout_reset(&sc->sc_diag_callout, 60 * hz,
1629 			    imxudiag, sc);
1630 	}
1631 #endif
1632 
1633 	/* If not yet open, drop the entire buffer content here */
1634 	if (!ISSET(tp->t_state, TS_ISOPEN)) {
1635 		sc->sc_rbuf_out = sc->sc_rbuf_in;
1636 		cc = 0;
1637 	}
1638 
1639 	outp = sc->sc_rbuf_out;
1640 
1641 #define	ERRBITS (IMX_URXD_PRERR|IMX_URXD_BRK|IMX_URXD_FRMERR|IMX_URXD_OVRRUN)
1642 
1643 	while (cc) {
1644 	        data = sc->sc_rbuf[outp];
1645 		code = data & IMX_URXD_RX_DATA;
1646 		if (ISSET(data, ERRBITS)) {
1647 			if (sc->sc_errors.err == 0)
1648 				callout_reset(&sc->sc_diag_callout,
1649 				    60 * hz, imxudiag, sc);
1650 			if (ISSET(data, IMX_URXD_OVRRUN))
1651 				sc->sc_errors.ovrrun++;
1652 			if (ISSET(data, IMX_URXD_BRK)) {
1653 				sc->sc_errors.brk++;
1654 				SET(code, TTY_FE);
1655 			}
1656 			if (ISSET(data, IMX_URXD_FRMERR)) {
1657 				sc->sc_errors.frmerr++;
1658 				SET(code, TTY_FE);
1659 			}
1660 			if (ISSET(data, IMX_URXD_PRERR)) {
1661 				sc->sc_errors.prerr++;
1662 				SET(code, TTY_PE);
1663 			}
1664 		}
1665 		if ((*rint)(code, tp) == -1) {
1666 			/*
1667 			 * The line discipline's buffer is out of space.
1668 			 */
1669 			if (!ISSET(sc->sc_rx_flags, IMXUART_RX_TTY_BLOCKED)) {
1670 				/*
1671 				 * We're either not using flow control, or the
1672 				 * line discipline didn't tell us to block for
1673 				 * some reason.  Either way, we have no way to
1674 				 * know when there's more space available, so
1675 				 * just drop the rest of the data.
1676 				 */
1677 				sc->sc_rbuf_out = sc->sc_rbuf_in;
1678 				cc = 0;
1679 			} else {
1680 				/*
1681 				 * Don't schedule any more receive processing
1682 				 * until the line discipline tells us there's
1683 				 * space available (through imxuhwiflow()).
1684 				 * Leave the rest of the data in the input
1685 				 * buffer.
1686 				 */
1687 				SET(sc->sc_rx_flags, IMXUART_RX_TTY_OVERFLOWED);
1688 			}
1689 			break;
1690 		}
1691 		outp = IMXUART_RBUF_INC(sc, outp, 1);
1692 		cc--;
1693 	}
1694 
1695 	if (cc != scc) {
1696 		sc->sc_rbuf_out = outp;
1697 		mutex_spin_enter(&sc->sc_lock);
1698 
1699 		cc = IMXUART_RBUF_SPACE(sc);
1700 
1701 		/* Buffers should be ok again, release possible block. */
1702 		if (cc >= sc->sc_r_lowat) {
1703 			if (ISSET(sc->sc_rx_flags, IMXUART_RX_IBUF_OVERFLOWED)) {
1704 				CLR(sc->sc_rx_flags, IMXUART_RX_IBUF_OVERFLOWED);
1705 				imxuart_control_rxint(sc, true);
1706 			}
1707 			if (ISSET(sc->sc_rx_flags, IMXUART_RX_IBUF_BLOCKED)) {
1708 				CLR(sc->sc_rx_flags, IMXUART_RX_IBUF_BLOCKED);
1709 				imxuart_hwiflow(sc);
1710 			}
1711 		}
1712 		mutex_spin_exit(&sc->sc_lock);
1713 	}
1714 }
1715 
1716 integrate void
1717 imxuart_txsoft(struct imxuart_softc *sc, struct tty *tp)
1718 {
1719 
1720 	CLR(tp->t_state, TS_BUSY);
1721 	if (ISSET(tp->t_state, TS_FLUSH))
1722 		CLR(tp->t_state, TS_FLUSH);
1723 	else
1724 		ndflush(&tp->t_outq, (int)(sc->sc_tba - tp->t_outq.c_cf));
1725 	(*tp->t_linesw->l_start)(tp);
1726 }
1727 
1728 integrate void
1729 imxuart_stsoft(struct imxuart_softc *sc, struct tty *tp)
1730 {
1731 #ifdef notyet
1732 	u_char msr, delta;
1733 
1734 	mutex_spin_enter(&sc->sc_lock);
1735 	msr = sc->sc_msr;
1736 	delta = sc->sc_msr_delta;
1737 	sc->sc_msr_delta = 0;
1738 	mutex_spin_exit(&sc->sc_lock);
1739 
1740 	if (ISSET(delta, sc->sc_msr_dcd)) {
1741 		/*
1742 		 * Inform the tty layer that carrier detect changed.
1743 		 */
1744 		(void) (*tp->t_linesw->l_modem)(tp, ISSET(msr, MSR_DCD));
1745 	}
1746 
1747 	if (ISSET(delta, sc->sc_msr_cts)) {
1748 		/* Block or unblock output according to flow control. */
1749 		if (ISSET(msr, sc->sc_msr_cts)) {
1750 			sc->sc_tx_stopped = 0;
1751 			(*tp->t_linesw->l_start)(tp);
1752 		} else {
1753 			sc->sc_tx_stopped = 1;
1754 		}
1755 	}
1756 
1757 #endif
1758 #ifdef IMXUART_DEBUG
1759 	if (imxuart_debug)
1760 		imxustatus(sc, "imxuart_stsoft");
1761 #endif
1762 }
1763 
1764 void
1765 imxusoft(void *arg)
1766 {
1767 	struct imxuart_softc *sc = arg;
1768 	struct tty *tp;
1769 
1770 	if (IMXUART_ISALIVE(sc) == 0)
1771 		return;
1772 
1773 	tp = sc->sc_tty;
1774 
1775 	if (sc->sc_rx_ready) {
1776 		sc->sc_rx_ready = 0;
1777 		imxuart_rxsoft(sc, tp);
1778 	}
1779 
1780 	if (sc->sc_st_check) {
1781 		sc->sc_st_check = 0;
1782 		imxuart_stsoft(sc, tp);
1783 	}
1784 
1785 	if (sc->sc_tx_done) {
1786 		sc->sc_tx_done = 0;
1787 		imxuart_txsoft(sc, tp);
1788 	}
1789 }
1790 
1791 int
1792 imxuintr(void *arg)
1793 {
1794 	struct imxuart_softc *sc = arg;
1795 	uint32_t usr1, usr2;
1796 	bus_space_tag_t iot = sc->sc_regs.ur_iot;
1797 	bus_space_handle_t ioh = sc->sc_regs.ur_ioh;
1798 
1799 
1800 	if (IMXUART_ISALIVE(sc) == 0)
1801 		return (0);
1802 
1803 	mutex_spin_enter(&sc->sc_lock);
1804 
1805 	usr2 = bus_space_read_4(iot, ioh, IMX_USR2);
1806 
1807 
1808 	do {
1809 		bus_space_write_4(iot, ioh, IMX_USR2,
1810 		    usr2 & (IMX_USR2_BRCD|IMX_USR2_ORE));
1811 		if (usr2 & IMX_USR2_BRCD) {
1812 			/* Break signal detected */
1813 			int cn_trapped = 0;
1814 
1815 			cn_check_magic(sc->sc_tty->t_dev,
1816 				       CNC_BREAK, imxuart_cnm_state);
1817 			if (cn_trapped)
1818 				continue;
1819 #if defined(KGDB) && !defined(DDB)
1820 			if (ISSET(sc->sc_hwflags, IMXUART_HW_KGDB)) {
1821 				kgdb_connect(1);
1822 				continue;
1823 			}
1824 #endif
1825 		}
1826 
1827 		if (usr2 & IMX_USR2_RDR)
1828 			imxuintr_read(sc);
1829 
1830 #ifdef	IMXUART_PPS
1831 		{
1832 			u_char	msr, delta;
1833 
1834 			msr = CSR_READ_1(regsp, IMXUART_REG_MSR);
1835 			delta = msr ^ sc->sc_msr;
1836 			sc->sc_msr = msr;
1837 			if ((sc->sc_pps_state.ppsparam.mode & PPS_CAPTUREBOTH) &&
1838 			    (delta & MSR_DCD)) {
1839 				mutex_spin_enter(&timecounter_lock);
1840 				pps_capture(&sc->sc_pps_state);
1841 				pps_event(&sc->sc_pps_state,
1842 				    (msr & MSR_DCD) ?
1843 				    PPS_CAPTUREASSERT :
1844 				    PPS_CAPTURECLEAR);
1845 				mutex_spin_exit(&timecounter_lock);
1846 			}
1847 		}
1848 #endif
1849 
1850 #ifdef notyet
1851 		/*
1852 		 * Process normal status changes
1853 		 */
1854 		if (ISSET(delta, sc->sc_msr_mask)) {
1855 			SET(sc->sc_msr_delta, delta);
1856 
1857 			/*
1858 			 * Stop output immediately if we lose the output
1859 			 * flow control signal or carrier detect.
1860 			 */
1861 			if (ISSET(~msr, sc->sc_msr_mask)) {
1862 				sc->sc_tbc = 0;
1863 				sc->sc_heldtbc = 0;
1864 #ifdef IMXUART_DEBUG
1865 				if (imxuart_debug)
1866 					imxustatus(sc, "imxuintr  ");
1867 #endif
1868 			}
1869 
1870 			sc->sc_st_check = 1;
1871 		}
1872 #endif
1873 
1874 		usr2 = bus_space_read_4(iot, ioh, IMX_USR2);
1875 	} while (usr2 & (IMX_USR2_RDR|IMX_USR2_BRCD));
1876 
1877 	usr1 = bus_space_read_4(iot, ioh, IMX_USR1);
1878 	if (usr1 & IMX_USR1_TRDY)
1879 		imxuintr_send(sc);
1880 
1881 	mutex_spin_exit(&sc->sc_lock);
1882 
1883 	/* Wake up the poller. */
1884 	softint_schedule(sc->sc_si);
1885 
1886 #if NRND > 0 && defined(RND_COM)
1887 	rnd_add_uint32(&sc->rnd_source, iir | lsr);
1888 #endif
1889 
1890 	return (1);
1891 }
1892 
1893 
1894 /*
1895  * called when there is least one character in rxfifo
1896  *
1897  */
1898 
1899 static void
1900 imxuintr_read(struct imxuart_softc *sc)
1901 {
1902 	int cc;
1903 	uint16_t rd;
1904 	uint32_t usr2;
1905 	bus_space_tag_t iot = sc->sc_regs.ur_iot;
1906 	bus_space_handle_t ioh = sc->sc_regs.ur_ioh;
1907 
1908 	cc = IMXUART_RBUF_SPACE(sc);
1909 
1910 	/* clear aging timer interrupt */
1911 	bus_space_write_4(iot, ioh, IMX_USR1, IMX_USR1_AGTIM);
1912 
1913 	while (cc > 0) {
1914 		int cn_trapped = 0;
1915 
1916 
1917 		sc->sc_rbuf[sc->sc_rbuf_in] = rd =
1918 		    bus_space_read_4(iot, ioh, IMX_URXD);
1919 
1920 		cn_check_magic(sc->sc_tty->t_dev,
1921 		    rd & 0xff, imxuart_cnm_state);
1922 
1923 		if (!cn_trapped) {
1924 			sc->sc_rbuf_in = IMXUART_RBUF_INC(sc, sc->sc_rbuf_in, 1);
1925 			cc--;
1926 		}
1927 
1928 		usr2 = bus_space_read_4(iot, ioh, IMX_USR2);
1929 		if (!(usr2 & IMX_USR2_RDR))
1930 			break;
1931 	}
1932 
1933 	/*
1934 	 * Current string of incoming characters ended because
1935 	 * no more data was available or we ran out of space.
1936 	 * Schedule a receive event if any data was received.
1937 	 * If we're out of space, turn off receive interrupts.
1938 	 */
1939 	if (!ISSET(sc->sc_rx_flags, IMXUART_RX_TTY_OVERFLOWED))
1940 		sc->sc_rx_ready = 1;
1941 	/*
1942 	 * See if we are in danger of overflowing a buffer. If
1943 	 * so, use hardware flow control to ease the pressure.
1944 	 */
1945 	if (!ISSET(sc->sc_rx_flags, IMXUART_RX_IBUF_BLOCKED) &&
1946 	    cc < sc->sc_r_hiwat) {
1947 		sc->sc_rx_flags |= IMXUART_RX_IBUF_BLOCKED;
1948 		imxuart_hwiflow(sc);
1949 	}
1950 
1951 	/*
1952 	 * If we're out of space, disable receive interrupts
1953 	 * until the queue has drained a bit.
1954 	 */
1955 	if (!cc) {
1956 		sc->sc_rx_flags |= IMXUART_RX_IBUF_OVERFLOWED;
1957 		imxuart_control_rxint(sc, false);
1958 	}
1959 }
1960 
1961 
1962 
1963 /*
1964  * find how many chars we can put into tx-fifo
1965  */
1966 static u_int
1967 imxuart_txfifo_space(struct imxuart_softc *sc)
1968 {
1969 	uint32_t usr1, usr2;
1970 	u_int cc;
1971 	bus_space_tag_t iot = sc->sc_regs.ur_iot;
1972 	bus_space_handle_t ioh = sc->sc_regs.ur_ioh;
1973 
1974 	usr2 = bus_space_read_4(iot, ioh, IMX_USR2);
1975 	if (usr2 & IMX_USR2_TXFE)
1976 		cc = sc->sc_txfifo_len;
1977 	else {
1978 		usr1 = bus_space_read_4(iot, ioh, IMX_USR1);
1979 		if (usr1 & IMX_USR1_TRDY)
1980 			cc = sc->sc_txfifo_thresh;
1981 		else
1982 			cc = 0;
1983 	}
1984 
1985 	return cc;
1986 }
1987 
1988 void
1989 imxuintr_send(struct imxuart_softc *sc)
1990 {
1991 	uint32_t usr2;
1992 	bus_space_tag_t iot = sc->sc_regs.ur_iot;
1993 	bus_space_handle_t ioh = sc->sc_regs.ur_ioh;
1994 	int cc = 0;
1995 
1996 	usr2 = bus_space_read_4(iot, ioh, IMX_USR2);
1997 
1998 	if (sc->sc_pending) {
1999 		if (usr2 & IMX_USR2_TXFE) {
2000 			imxuart_load_pendings(sc);
2001 			sc->sc_tbc = sc->sc_heldtbc;
2002 			sc->sc_heldtbc = 0;
2003 		}
2004 		else {
2005 			/* wait for TX fifo empty */
2006 			imxuart_control_txint(sc, true);
2007 			return;
2008 		}
2009 	}
2010 
2011 	cc = imxuart_txfifo_space(sc);
2012 	cc = MIN(cc, sc->sc_tbc);
2013 
2014 	if (cc > 0) {
2015 		bus_space_write_multi_1(iot, ioh, IMX_UTXD, sc->sc_tba, cc);
2016 		sc->sc_tbc -= cc;
2017 		sc->sc_tba += cc;
2018 	}
2019 
2020 	if (sc->sc_tbc > 0)
2021 		imxuart_control_txint(sc, true);
2022 	else {
2023 		/* no more chars to send.
2024 		   we don't need tx interrupt any more. */
2025 		imxuart_control_txint(sc, false);
2026 		if (sc->sc_tx_busy) {
2027 			sc->sc_tx_busy = 0;
2028 			sc->sc_tx_done = 1;
2029 		}
2030 	}
2031 }
2032 
2033 static void
2034 imxuart_disable_all_interrupts(struct imxuart_softc *sc)
2035 {
2036 	bus_space_tag_t iot = sc->sc_regs.ur_iot;
2037 	bus_space_handle_t ioh = sc->sc_regs.ur_ioh;
2038 
2039 	sc->sc_ucr1 &= ~IMXUART_INTRS_UCR1;
2040 	sc->sc_ucr2 &= ~IMXUART_INTRS_UCR2;
2041 	sc->sc_ucr3 &= ~IMXUART_INTRS_UCR3;
2042 	sc->sc_ucr4 &= ~IMXUART_INTRS_UCR4;
2043 
2044 
2045 	bus_space_write_region_4(iot, ioh, IMX_UCR1, sc->sc_ucr, 4);
2046 }
2047 
2048 static void
2049 imxuart_control_rxint(struct imxuart_softc *sc, bool enable)
2050 {
2051 	bus_space_tag_t iot = sc->sc_regs.ur_iot;
2052 	bus_space_handle_t ioh = sc->sc_regs.ur_ioh;
2053 	uint32_t ucr1, ucr2;
2054 
2055 	ucr1 = sc->sc_ucr1;
2056 	ucr2 = sc->sc_ucr2;
2057 
2058 	if (enable) {
2059 		ucr1 |= IMX_UCR1_RRDYEN;
2060 		ucr2 |= IMX_UCR2_ATEN;
2061 	}
2062 	else {
2063 		ucr1 &= ~IMX_UCR1_RRDYEN;
2064 		ucr2 &= ~IMX_UCR2_ATEN;
2065 	}
2066 
2067 	if (ucr1 != sc->sc_ucr1 || ucr2 != sc->sc_ucr2) {
2068 		sc->sc_ucr1 = ucr1;
2069 		sc->sc_ucr2 = ucr2;
2070 		bus_space_write_region_4(iot, ioh, IMX_UCR1, sc->sc_ucr, 2);
2071 	}
2072 }
2073 
2074 static void
2075 imxuart_control_txint(struct imxuart_softc *sc, bool enable)
2076 {
2077 	bus_space_tag_t iot = sc->sc_regs.ur_iot;
2078 	bus_space_handle_t ioh = sc->sc_regs.ur_ioh;
2079 	uint32_t ucr1;
2080 	uint32_t mask;
2081 
2082 	/* if parameter change is pending, get interrupt when Tx fifo
2083 	   is completely empty.  otherwise, get interrupt when txfifo
2084 	   has less characters than threshold */
2085 	mask = sc->sc_pending ? IMX_UCR1_TXMPTYEN : IMX_UCR1_TRDYEN;
2086 
2087 	ucr1 = sc->sc_ucr1;
2088 
2089 	CLR(ucr1, IMX_UCR1_TXMPTYEN|IMX_UCR1_TRDYEN);
2090 	if (enable)
2091 		SET(ucr1, mask);
2092 
2093 	if (ucr1 != sc->sc_ucr1) {
2094 		bus_space_write_4(iot, ioh, IMX_UCR1, ucr1);
2095 		sc->sc_ucr1 = ucr1;
2096 	}
2097 }
2098 
2099 
2100 static void
2101 imxuart_load_params(struct imxuart_softc *sc)
2102 {
2103 	uint32_t ucr2;
2104 	bus_space_tag_t iot = sc->sc_regs.ur_iot;
2105 	bus_space_handle_t ioh = sc->sc_regs.ur_ioh;
2106 
2107 	ucr2 = (sc->sc_ucr2_d & ~IMX_UCR2_ATEN) |
2108 	    (sc->sc_ucr2 & IMX_UCR2_ATEN);
2109 
2110 	bus_space_write_4(iot, ioh, IMX_UCR2, ucr2);
2111 	sc->sc_ucr2 = ucr2;
2112 }
2113 
2114 static void
2115 imxuart_load_speed(struct imxuart_softc *sc)
2116 {
2117 	bus_space_tag_t iot = sc->sc_regs.ur_iot;
2118 	bus_space_handle_t ioh = sc->sc_regs.ur_ioh;
2119 	int n, rfdiv, ufcr;
2120 
2121 #ifdef notyet
2122 	/*
2123 	 * Set the FIFO threshold based on the receive speed.
2124 	 *
2125 	 *  * If it's a low speed, it's probably a mouse or some other
2126 	 *    interactive device, so set the threshold low.
2127 	 *  * If it's a high speed, trim the trigger level down to prevent
2128 	 *    overflows.
2129 	 *  * Otherwise set it a bit higher.
2130 	 */
2131 	if (t->c_ospeed <= 1200)
2132 		sc->sc_fifo = FIFO_ENABLE | FIFO_TRIGGER_1;
2133 	else if (t->c_ospeed <= 38400)
2134 		sc->sc_fifo = FIFO_ENABLE | FIFO_TRIGGER_8;
2135 	else
2136 		sc->sc_fifo = FIFO_ENABLE | FIFO_TRIGGER_4;
2137 #endif
2138 
2139 	n = 32 - sc->sc_txfifo_thresh;
2140 	n = MAX(2, n);
2141 
2142 	rfdiv = IMX_UFCR_DIVIDER_TO_RFDIV(imxuart_freqdiv);
2143 
2144 	ufcr = (n << IMX_UFCR_TXTL_SHIFT) |
2145 		(rfdiv << IMX_UFCR_RFDIV_SHIFT) |
2146 		(16 << IMX_UFCR_RXTL_SHIFT);
2147 
2148 	/* keep DCE/DTE bit */
2149 	ufcr |= bus_space_read_4(iot, ioh, IMX_UFCR) & IMX_UFCR_DCEDTE;
2150 
2151 	bus_space_write_4(iot, ioh, IMX_UFCR, ufcr);
2152 
2153 	/* UBIR must updated before UBMR */
2154 	bus_space_write_4(iot, ioh,
2155 	    IMX_UBIR, sc->sc_ratio.numerator);
2156 	bus_space_write_4(iot, ioh,
2157 	    IMX_UBMR, sc->sc_ratio.modulator);
2158 
2159 
2160 }
2161 
2162 
2163 static void
2164 imxuart_load_pendings(struct imxuart_softc *sc)
2165 {
2166 	if (sc->sc_pending & IMXUART_PEND_PARAM)
2167 		imxuart_load_params(sc);
2168 	if (sc->sc_pending & IMXUART_PEND_SPEED)
2169 		imxuart_load_speed(sc);
2170 	sc->sc_pending = 0;
2171 }
2172 
2173 #if defined(IMXUARTCONSOLE) || defined(KGDB)
2174 
2175 /*
2176  * The following functions are polled getc and putc routines, shared
2177  * by the console and kgdb glue.
2178  *
2179  * The read-ahead code is so that you can detect pending in-band
2180  * cn_magic in polled mode while doing output rather than having to
2181  * wait until the kernel decides it needs input.
2182  */
2183 
2184 #define	READAHEAD_RING_LEN	16
2185 static int imxuart_readahead[READAHEAD_RING_LEN];
2186 static int imxuart_readahead_in = 0;
2187 static int imxuart_readahead_out = 0;
2188 #define	READAHEAD_IS_EMPTY()	(imxuart_readahead_in==imxuart_readahead_out)
2189 #define	READAHEAD_IS_FULL()	\
2190 	(((imxuart_readahead_in+1) & (READAHEAD_RING_LEN-1)) ==imxuart_readahead_out)
2191 
2192 int
2193 imxuart_common_getc(dev_t dev, struct imxuart_regs *regsp)
2194 {
2195 	int s = splserial();
2196 	u_char c;
2197 	bus_space_tag_t iot = regsp->ur_iot;
2198 	bus_space_handle_t ioh = regsp->ur_ioh;
2199 	uint32_t usr2;
2200 
2201 	/* got a character from reading things earlier */
2202 	if (imxuart_readahead_in != imxuart_readahead_out) {
2203 
2204 		c = imxuart_readahead[imxuart_readahead_out];
2205 		imxuart_readahead_out = (imxuart_readahead_out + 1) &
2206 		    (READAHEAD_RING_LEN-1);
2207 		splx(s);
2208 		return (c);
2209 	}
2210 
2211 	/* block until a character becomes available */
2212 	while (!((usr2 = bus_space_read_4(iot, ioh, IMX_USR2)) & IMX_USR2_RDR))
2213 		;
2214 
2215 	c = 0xff & bus_space_read_4(iot, ioh, IMX_URXD);
2216 
2217 	{
2218 		int cn_trapped = 0; /* unused */
2219 #ifdef DDB
2220 		extern int db_active;
2221 		if (!db_active)
2222 #endif
2223 			cn_check_magic(dev, c, imxuart_cnm_state);
2224 	}
2225 	splx(s);
2226 	return (c);
2227 }
2228 
2229 void
2230 imxuart_common_putc(dev_t dev, struct imxuart_regs *regsp, int c)
2231 {
2232 	int s = splserial();
2233 	int cin, timo;
2234 	bus_space_tag_t iot = regsp->ur_iot;
2235 	bus_space_handle_t ioh = regsp->ur_ioh;
2236 	uint32_t usr2;
2237 
2238 	if (!READAHEAD_IS_FULL() &&
2239 	    ((usr2 = bus_space_read_4(iot, ioh, IMX_USR2)) & IMX_USR2_RDR)) {
2240 
2241 		int cn_trapped = 0;
2242 		cin = bus_space_read_4(iot, ioh, IMX_URXD);
2243 		cn_check_magic(dev, cin & 0xff, imxuart_cnm_state);
2244 		imxuart_readahead_in = (imxuart_readahead_in + 1) &
2245 		    (READAHEAD_RING_LEN-1);
2246 	}
2247 
2248 	/* wait for any pending transmission to finish */
2249 	timo = 150000;
2250 	do {
2251 		if (bus_space_read_4(iot, ioh, IMX_USR1) & IMX_USR1_TRDY) {
2252 			bus_space_write_4(iot, ioh, IMX_UTXD, c);
2253 			break;
2254 		}
2255 	} while(--timo > 0);
2256 
2257 	IMXUART_BARRIER(regsp, BR | BW);
2258 
2259 	splx(s);
2260 }
2261 
2262 /*
2263  * Initialize UART for use as console or KGDB line.
2264  */
2265 int
2266 imxuart_init(struct imxuart_regs *regsp, int rate, tcflag_t cflag)
2267 {
2268 	struct imxuart_baudrate_ratio ratio;
2269 	int rfdiv = IMX_UFCR_DIVIDER_TO_RFDIV(imxuart_freqdiv);
2270 	uint32_t ufcr;
2271 
2272 	if (bus_space_map(regsp->ur_iot, regsp->ur_iobase, IMX_UART_SIZE, 0,
2273 		&regsp->ur_ioh))
2274 		return ENOMEM; /* ??? */
2275 
2276 	if (imxuspeed(rate, &ratio) < 0)
2277 		return EINVAL;
2278 
2279 	/* UBIR must updated before UBMR */
2280 	bus_space_write_4(regsp->ur_iot, regsp->ur_ioh,
2281 	    IMX_UBIR, ratio.numerator);
2282 	bus_space_write_4(regsp->ur_iot, regsp->ur_ioh,
2283 	    IMX_UBMR, ratio.modulator);
2284 
2285 
2286 	/* XXX: DTREN, DPEC */
2287 	bus_space_write_4(regsp->ur_iot, regsp->ur_ioh, IMX_UCR3,
2288 	    IMX_UCR3_DSR|IMX_UCR3_RXDMUXSEL);
2289 
2290 	ufcr = (8 << IMX_UFCR_TXTL_SHIFT) | (rfdiv << IMX_UFCR_RFDIV_SHIFT) |
2291 		(1 << IMX_UFCR_RXTL_SHIFT);
2292 	/* XXX: keep DCE/DTE bit */
2293 	ufcr |= bus_space_read_4(regsp->ur_iot, regsp->ur_ioh, IMX_UFCR) &
2294 		IMX_UFCR_DCEDTE;
2295 
2296 	bus_space_write_4(regsp->ur_iot, regsp->ur_ioh, IMX_UFCR, ufcr);
2297 
2298 	bus_space_write_4(regsp->ur_iot, regsp->ur_ioh, IMX_ONEMS,
2299 	    imxuart_freq / imxuart_freqdiv / 1000);
2300 
2301 	bus_space_write_4(regsp->ur_iot, regsp->ur_ioh, IMX_UCR2,
2302 			  IMX_UCR2_IRTS|
2303 			  IMX_UCR2_CTSC|
2304 			  IMX_UCR2_WS|IMX_UCR2_TXEN|
2305 			  IMX_UCR2_RXEN|IMX_UCR2_SRST);
2306 	/* clear status registers */
2307 	bus_space_write_4(regsp->ur_iot, regsp->ur_ioh, IMX_USR1, 0xffff);
2308 	bus_space_write_4(regsp->ur_iot, regsp->ur_ioh, IMX_USR2, 0xffff);
2309 
2310 
2311 	bus_space_write_4(regsp->ur_iot, regsp->ur_ioh, IMX_UCR1,
2312 	    IMX_UCR1_UARTEN);
2313 
2314 	return (0);
2315 }
2316 
2317 
2318 #endif
2319 
2320 
2321 #ifdef	IMXUARTCONSOLE
2322 /*
2323  * Following are all routines needed for UART to act as console
2324  */
2325 struct consdev imxucons = {
2326 	NULL, NULL, imxucngetc, imxucnputc, imxucnpollc, NULL, NULL, NULL,
2327 	NODEV, CN_NORMAL
2328 };
2329 
2330 
2331 int
2332 imxuart_cons_attach(bus_space_tag_t iot, paddr_t iobase, u_int rate,
2333 		    tcflag_t cflag)
2334 {
2335 	struct imxuart_regs regs;
2336 	int res;
2337 
2338 	regs.ur_iot = iot;
2339 	regs.ur_iobase = iobase;
2340 
2341 	res = imxuart_init(&regs, rate, cflag);
2342 	if (res)
2343 		return (res);
2344 
2345 	cn_tab = &imxucons;
2346 	cn_init_magic(&imxuart_cnm_state);
2347 	cn_set_magic("\047\001"); /* default magic is BREAK */
2348 
2349 	imxuconsrate = rate;
2350 	imxuconscflag = cflag;
2351 
2352 	imxuconsregs = regs;
2353 
2354 	return 0;
2355 }
2356 
2357 int
2358 imxucngetc(dev_t dev)
2359 {
2360 	return (imxuart_common_getc(dev, &imxuconsregs));
2361 }
2362 
2363 /*
2364  * Console kernel output character routine.
2365  */
2366 void
2367 imxucnputc(dev_t dev, int c)
2368 {
2369 	imxuart_common_putc(dev, &imxuconsregs, c);
2370 }
2371 
2372 void
2373 imxucnpollc(dev_t dev, int on)
2374 {
2375 
2376 }
2377 
2378 #endif	/* IMXUARTCONSOLE */
2379 
2380 #ifdef KGDB
2381 int
2382 imxuart_kgdb_attach(bus_space_tag_t iot, paddr_t iobase, u_int rate,
2383     tcflag_t cflag)
2384 {
2385 	int res;
2386 
2387 	if (iot == imxuconsregs.ur_iot &&
2388 	    iobase == imxuconsregs.ur_iobase) {
2389 #if !defined(DDB)
2390 		return (EBUSY); /* cannot share with console */
2391 #else
2392 		imxu_kgdb_regs.ur_iot = iot;
2393 		imxu_kgdb_regs.ur_ioh = imxuconsregs.ur_ioh;
2394 		imxu_kgdb_regs.ur_iobase = iobase;
2395 #endif
2396 	} else {
2397 		imxu_kgdb_regs.ur_iot = iot;
2398 		imxu_kgdb_regs.ur_iobase = iobase;
2399 
2400 		res = imxuart_init(&imxu_kgdb_regs, rate, cflag);
2401 		if (res)
2402 			return (res);
2403 
2404 		/*
2405 		 * XXXfvdl this shouldn't be needed, but the cn_magic goo
2406 		 * expects this to be initialized
2407 		 */
2408 		cn_init_magic(&imxuart_cnm_state);
2409 		cn_set_magic("\047\001");
2410 	}
2411 
2412 	kgdb_attach(imxuart_kgdb_getc, imxuart_kgdb_putc, &imxu_kgdb_regs);
2413 	kgdb_dev = 123; /* unneeded, only to satisfy some tests */
2414 
2415 	return (0);
2416 }
2417 
2418 /* ARGSUSED */
2419 int
2420 imxuart_kgdb_getc(void *arg)
2421 {
2422 	struct imxuart_regs *regs = arg;
2423 
2424 	return (imxuart_common_getc(NODEV, regs));
2425 }
2426 
2427 /* ARGSUSED */
2428 void
2429 imxuart_kgdb_putc(void *arg, int c)
2430 {
2431 	struct imxuart_regs *regs = arg;
2432 
2433 	imxuart_common_putc(NODEV, regs, c);
2434 }
2435 #endif /* KGDB */
2436 
2437 /* helper function to identify the imxu ports used by
2438  console or KGDB (and not yet autoconf attached) */
2439 int
2440 imxuart_is_console(bus_space_tag_t iot, bus_addr_t iobase, bus_space_handle_t *ioh)
2441 {
2442 	bus_space_handle_t help;
2443 
2444 	if (!imxuconsattached &&
2445 	    iot == imxuconsregs.ur_iot && iobase == imxuconsregs.ur_iobase)
2446 		help = imxuconsregs.ur_ioh;
2447 #ifdef KGDB
2448 	else if (!imxu_kgdb_attached &&
2449 	    iot == imxu_kgdb_regs.ur_iot && iobase == imxu_kgdb_regs.ur_iobase)
2450 		help = imxu_kgdb_regs.ur_ioh;
2451 #endif
2452 	else
2453 		return (0);
2454 
2455 	if (ioh)
2456 		*ioh = help;
2457 	return (1);
2458 }
2459 
2460 #ifdef notyet
2461 
2462 bool
2463 imxuart_cleanup(device_t self, int how)
2464 {
2465 /*
2466  * this routine exists to serve as a shutdown hook for systems that
2467  * have firmware which doesn't interact properly with a imxuart device in
2468  * FIFO mode.
2469  */
2470 	struct imxuart_softc *sc = device_private(self);
2471 
2472 	if (ISSET(sc->sc_hwflags, IMXUART_HW_FIFO))
2473 		UR_WRITE_1(&sc->sc_regs, IMXUART_REG_FIFO, 0);
2474 
2475 	return true;
2476 }
2477 #endif
2478 
2479 #ifdef notyet
2480 bool
2481 imxuart_suspend(device_t self PMF_FN_ARGS)
2482 {
2483 	struct imxuart_softc *sc = device_private(self);
2484 
2485 	UR_WRITE_1(&sc->sc_regs, IMXUART_REG_IER, 0);
2486 	(void)CSR_READ_1(&sc->sc_regs, IMXUART_REG_IIR);
2487 
2488 	return true;
2489 }
2490 #endif
2491 
2492 #ifdef notyet
2493 bool
2494 imxuart_resume(device_t self PMF_FN_ARGS)
2495 {
2496 	struct imxuart_softc *sc = device_private(self);
2497 
2498 	mutex_spin_enter(&sc->sc_lock);
2499 	imxuart_loadchannelregs(sc);
2500 	mutex_spin_exit(&sc->sc_lock);
2501 
2502 	return true;
2503 }
2504 #endif
2505 
2506 static void
2507 imxuart_enable_debugport(struct imxuart_softc *sc)
2508 {
2509 	bus_space_tag_t iot = sc->sc_regs.ur_iot;
2510 	bus_space_handle_t ioh = sc->sc_regs.ur_ioh;
2511 
2512 	if (sc->sc_hwflags & (IMXUART_HW_CONSOLE|IMXUART_HW_KGDB)) {
2513 
2514 		/* Turn on line break interrupt, set carrier. */
2515 
2516 		sc->sc_ucr3 |= IMX_UCR3_DSR;
2517 		bus_space_write_4(iot, ioh, IMX_UCR3, sc->sc_ucr3);
2518 
2519 		sc->sc_ucr4 |= IMX_UCR4_BKEN;
2520 		bus_space_write_4(iot, ioh, IMX_UCR4, sc->sc_ucr4);
2521 
2522 		sc->sc_ucr2 |= IMX_UCR2_TXEN|IMX_UCR2_RXEN|
2523 		    IMX_UCR2_CTS;
2524 		bus_space_write_4(iot, ioh, IMX_UCR2, sc->sc_ucr2);
2525 
2526 		sc->sc_ucr1 |= IMX_UCR1_UARTEN;
2527 		bus_space_write_4(iot, ioh, IMX_UCR1, sc->sc_ucr1);
2528 	}
2529 }
2530 
2531 
2532 void
2533 imxuart_set_frequency(u_int freq, u_int div)
2534 {
2535 	imxuart_freq = freq;
2536 	imxuart_freqdiv = div;
2537 }
2538