1 /* $NetBSD: imxuart.c,v 1.30 2022/10/26 23:38:06 riastradh 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 1.30 2022/10/26 23:38:06 riastradh Exp $");
100 
101 #include "opt_imxuart.h"
102 #include "opt_ddb.h"
103 #include "opt_ddbparam.h"
104 #include "opt_kgdb.h"
105 #include "opt_lockdebug.h"
106 #include "opt_multiprocessor.h"
107 #include "opt_ntp.h"
108 #include "opt_imxuart.h"
109 
110 #ifdef RND_COM
111 #include <sys/rndsource.h>
112 #endif
113 
114 #ifndef   IMXUART_TOLERANCE
115 #define   IMXUART_TOLERANCE   30        /* baud rate tolerance, in 0.1% units */
116 #endif
117 
118 #ifndef   IMXUART_FREQDIV
119 #define   IMXUART_FREQDIV               2         /* XXX */
120 #endif
121 
122 #ifndef   IMXUART_FREQ
123 #define   IMXUART_FREQ        (56900000)
124 #endif
125 
126 /*
127  * Override cnmagic(9) macro before including <sys/systm.h>.
128  * We need to know if cn_check_magic triggered debugger, so set a flag.
129  * Callers of cn_check_magic must declare int cn_trapped = 0;
130  * XXX: this is *ugly*!
131  */
132 #define   cn_trap()                               \
133           do {                                              \
134                     console_debugger();           \
135                     cn_trapped = 1;                         \
136           } while (/* CONSTCOND */ 0)
137 
138 #include <sys/param.h>
139 #include <sys/systm.h>
140 #include <sys/ioctl.h>
141 #include <sys/select.h>
142 #include <sys/poll.h>
143 #include <sys/tty.h>
144 #include <sys/proc.h>
145 #include <sys/conf.h>
146 #include <sys/file.h>
147 #include <sys/uio.h>
148 #include <sys/kernel.h>
149 #include <sys/syslog.h>
150 #include <sys/device.h>
151 #include <sys/kmem.h>
152 #include <sys/timepps.h>
153 #include <sys/vnode.h>
154 #include <sys/kauth.h>
155 #include <sys/intr.h>
156 
157 #include <sys/bus.h>
158 
159 #include <ddb/db_active.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 int       imxuspeed(long, struct imxuart_baudrate_ratio *);
170 int       imxuparam(struct tty *, struct termios *);
171 void      imxustart(struct tty *);
172 int       imxuhwiflow(struct tty *, int);
173 
174 void      imxuart_shutdown(struct imxuart_softc *);
175 void      imxuart_loadchannelregs(struct imxuart_softc *);
176 void      imxuart_hwiflow(struct imxuart_softc *);
177 void      imxuart_break(struct imxuart_softc *, bool);
178 void      imxuart_modem(struct imxuart_softc *, int);
179 void      tiocm_to_imxu(struct imxuart_softc *, u_long, int);
180 int       imxuart_to_tiocm(struct imxuart_softc *);
181 void      imxuart_iflush(struct imxuart_softc *);
182 int       imxuintr(void *);
183 
184 int       imxuart_common_getc(dev_t, struct imxuart_regs *);
185 void      imxuart_common_putc(dev_t, struct imxuart_regs *, int);
186 
187 
188 int       imxuart_init(struct imxuart_regs *, int, tcflag_t, int);
189 
190 int       imxucngetc(dev_t);
191 void      imxucnputc(dev_t, int);
192 void      imxucnpollc(dev_t, int);
193 
194 static void imxuintr_read(struct imxuart_softc *);
195 static void imxuintr_send(struct imxuart_softc *);
196 
197 static void imxuart_enable_debugport(struct imxuart_softc *);
198 static void imxuart_disable_all_interrupts(struct imxuart_softc *);
199 static void imxuart_control_rxint(struct imxuart_softc *, bool);
200 static void imxuart_control_txint(struct imxuart_softc *, bool);
201 static u_int imxuart_txfifo_space(struct imxuart_softc *sc);
202 
203 static    uint32_t  cflag_to_ucr2(tcflag_t, uint32_t);
204 
205 #define   integrate static inline
206 void      imxusoft(void *);
207 integrate void imxuart_rxsoft(struct imxuart_softc *, struct tty *);
208 integrate void imxuart_txsoft(struct imxuart_softc *, struct tty *);
209 integrate void imxuart_stsoft(struct imxuart_softc *, struct tty *);
210 integrate void imxuart_schedrx(struct imxuart_softc *);
211 void      imxudiag(void *);
212 static void imxuart_load_speed(struct imxuart_softc *);
213 static void imxuart_load_params(struct imxuart_softc *);
214 integrate void imxuart_load_pendings(struct imxuart_softc *);
215 
216 
217 extern struct cfdriver imxuart_cd;
218 
219 dev_type_open(imxuopen);
220 dev_type_close(imxuclose);
221 dev_type_read(imxuread);
222 dev_type_write(imxuwrite);
223 dev_type_ioctl(imxuioctl);
224 dev_type_stop(imxustop);
225 dev_type_tty(imxutty);
226 dev_type_poll(imxupoll);
227 
228 const struct cdevsw imxcom_cdevsw = {
229           .d_open = imxuopen,
230           .d_close = imxuclose,
231           .d_read = imxuread,
232           .d_write = imxuwrite,
233           .d_ioctl = imxuioctl,
234           .d_stop = imxustop,
235           .d_tty = imxutty,
236           .d_poll = imxupoll,
237           .d_mmap = nommap,
238           .d_kqfilter = ttykqfilter,
239           .d_discard = nodiscard,
240           .d_flag = D_TTY
241 };
242 
243 /*
244  * Make this an option variable one can patch.
245  * But be warned:  this must be a power of 2!
246  */
247 u_int imxuart_rbuf_size = IMXUART_RING_SIZE;
248 
249 /* Stop input when 3/4 of the ring is full; restart when only 1/4 is full. */
250 u_int imxuart_rbuf_hiwat = (IMXUART_RING_SIZE * 1) / 4;
251 u_int imxuart_rbuf_lowat = (IMXUART_RING_SIZE * 3) / 4;
252 
253 static struct imxuart_regs imxuconsregs;
254 static int imxuconsattached;
255 static int imxuconsrate;
256 static tcflag_t imxuconscflag;
257 static struct cnm_state imxuart_cnm_state;
258 
259 u_int imxuart_freq = IMXUART_FREQ;
260 u_int imxuart_freqdiv = IMXUART_FREQDIV;
261 
262 #ifdef KGDB
263 #include <sys/kgdb.h>
264 
265 static struct imxuart_regs imxu_kgdb_regs;
266 static int imxu_kgdb_attached;
267 
268 int       imxuart_kgdb_getc(void *);
269 void      imxuart_kgdb_putc(void *, int);
270 #endif /* KGDB */
271 
272 #define   IMXUART_DIALOUT_MASK          TTDIALOUT_MASK
273 
274 #define   IMXUART_UNIT(x)               TTUNIT(x)
275 #define   IMXUART_DIALOUT(x)  TTDIALOUT(x)
276 
277 #define   IMXUART_ISALIVE(sc) ((sc)->enabled != 0 && \
278                                device_is_active((sc)->sc_dev))
279 
280 #define   BR        BUS_SPACE_BARRIER_READ
281 #define   BW        BUS_SPACE_BARRIER_WRITE
282 #define   IMXUART_BARRIER(r, f) \
283           bus_space_barrier((r)->ur_iot, (r)->ur_ioh, 0, IMX_UART_SIZE, (f))
284 
285 
286 void
imxuart_attach_common(device_t parent,device_t self,bus_space_tag_t iot,paddr_t iobase,size_t size,int intr,int flags)287 imxuart_attach_common(device_t parent, device_t self,
288     bus_space_tag_t iot, paddr_t iobase, size_t size, int intr, int flags)
289 {
290           struct imxuart_softc *sc = device_private(self);
291           struct imxuart_regs *regsp = &sc->sc_regs;
292           bus_space_handle_t ioh;
293 
294           aprint_naive("\n");
295           aprint_normal("\n");
296 
297           sc->sc_dev = self;
298 
299           if (size <= 0)
300                     size = IMX_UART_SIZE;
301 
302           sc->sc_intr = intr;
303           regsp->ur_iot = iot;
304           regsp->ur_iobase = iobase;
305 
306           if (bus_space_map(iot, regsp->ur_iobase, size, 0, &ioh)) {
307                     return;
308           }
309           regsp->ur_ioh = ioh;
310 
311           sc->sc_ih = intr_establish(sc->sc_intr, IPL_SERIAL, IST_LEVEL,
312               imxuintr, sc);
313           if (sc->sc_ih == NULL) {
314                     aprint_error_dev(sc->sc_dev, "intr_establish failed\n");
315                     return;
316           }
317 
318           imxuart_attach_subr(sc);
319 }
320 
321 void
imxuart_attach_subr(struct imxuart_softc * sc)322 imxuart_attach_subr(struct imxuart_softc *sc)
323 {
324           struct imxuart_regs *regsp = &sc->sc_regs;
325           bus_space_tag_t iot = regsp->ur_iot;
326           bus_space_handle_t ioh = regsp->ur_ioh;
327           struct tty *tp;
328 
329           callout_init(&sc->sc_diag_callout, 0);
330           mutex_init(&sc->sc_lock, MUTEX_DEFAULT, IPL_HIGH);
331 
332           if (regsp->ur_iobase != imxuconsregs.ur_iobase)
333                     imxuart_init(&sc->sc_regs, TTYDEF_SPEED, TTYDEF_CFLAG, false);
334 
335           bus_space_read_region_4(iot, ioh, IMX_UCR1, sc->sc_ucr, 4);
336           sc->sc_ucr2_d = sc->sc_ucr2;
337 
338           /* Disable interrupts before configuring the device. */
339           imxuart_disable_all_interrupts(sc);
340 
341           if (regsp->ur_iobase == imxuconsregs.ur_iobase) {
342                     imxuconsattached = 1;
343 
344                     /* Make sure the console is always "hardwired". */
345 #if 0
346                     delay(10000);                           /* wait for output to finish */
347 #endif
348                     SET(sc->sc_hwflags, IMXUART_HW_CONSOLE);
349                     SET(sc->sc_swflags, TIOCFLAG_SOFTCAR);
350           }
351 
352 
353           tp = tty_alloc();
354           tp->t_oproc = imxustart;
355           tp->t_param = imxuparam;
356           tp->t_hwiflow = imxuhwiflow;
357 
358           sc->sc_tty = tp;
359           sc->sc_rbuf = kmem_alloc(sizeof (*sc->sc_rbuf) * imxuart_rbuf_size,
360               KM_SLEEP);
361           sc->sc_rbuf_size = imxuart_rbuf_size;
362           sc->sc_rbuf_in = sc->sc_rbuf_out = 0;
363           sc->sc_txfifo_len = 32;
364           sc->sc_txfifo_thresh = 16;    /* when USR1.TRDY, fifo has space
365                                                    * for this many characters */
366 
367           tty_attach(tp);
368 
369           if (ISSET(sc->sc_hwflags, IMXUART_HW_CONSOLE)) {
370                     int maj;
371 
372                     /* locate the major number */
373                     maj = cdevsw_lookup_major(&imxcom_cdevsw);
374 
375                     if (maj != NODEVMAJOR) {
376                               tp->t_dev = cn_tab->cn_dev = makedev(maj,
377                                   device_unit(sc->sc_dev));
378 
379                               aprint_normal_dev(sc->sc_dev, "console\n");
380                     }
381           }
382 
383 #ifdef KGDB
384           /*
385            * Allow kgdb to "take over" this port.  If this is
386            * not the console and is the kgdb device, it has
387            * exclusive use.  If it's the console _and_ the
388            * kgdb device, it doesn't.
389            */
390           if (regsp->ur_iobase == imxu_kgdb_regs.ur_iobase) {
391                     if (!ISSET(sc->sc_hwflags, IMXUART_HW_CONSOLE)) {
392                               imxu_kgdb_attached = 1;
393 
394                               SET(sc->sc_hwflags, IMXUART_HW_KGDB);
395                     }
396                     aprint_normal_dev(sc->sc_dev, "kgdb\n");
397           }
398 #endif
399 
400           sc->sc_si = softint_establish(SOFTINT_SERIAL, imxusoft, sc);
401 
402 #ifdef RND_COM
403           rnd_attach_source(&sc->rnd_source, device_xname(sc->sc_dev),
404                                 RND_TYPE_TTY, RND_FLAG_COLLECT_TIME |
405                                                   RND_FLAG_ESTIMATE_TIME);
406 #endif
407 
408           /* if there are no enable/disable functions, assume the device
409              is always enabled */
410           if (!sc->enable)
411                     sc->enabled = 1;
412 
413           imxuart_enable_debugport(sc);
414 
415           SET(sc->sc_hwflags, IMXUART_HW_DEV_OK);
416 
417           //shutdownhook_establish(imxuart_shutdownhook, sc);
418 
419 
420 #if 0
421           {
422                     uint32_t reg;
423                     reg = bus_space_read_4(iot, ioh, IMX_UCR1);
424                     reg |= IMX_UCR1_TXDMAEN | IMX_UCR1_RXDMAEN;
425                     bus_space_write_4(iot, ioh, IMX_UCR1, reg);
426           }
427 #endif
428 }
429 
430 /*
431  * baudrate = RefFreq / (16 * (UMBR + 1)/(UBIR + 1))
432  *
433  * (UBIR + 1) / (UBMR + 1) = (16 * BaurdRate) / RefFreq
434  */
435 
436 static long
gcd(long m,long n)437 gcd(long m, long n)
438 {
439 
440           if (m < n)
441                     return gcd(n, m);
442 
443           if (n <= 0)
444                     return m;
445           return gcd(n, m % n);
446 }
447 
448 int
imxuspeed(long speed,struct imxuart_baudrate_ratio * ratio)449 imxuspeed(long speed, struct imxuart_baudrate_ratio *ratio)
450 {
451 #define   divrnd(n, q)        (((n)*2/(q)+1)/2)   /* divide and round off */
452           long b = 16 * speed;
453           long f = imxuart_freq / imxuart_freqdiv;
454           long d;
455           int err = 0;
456 
457           /* reduce b/f */
458           while ((f > (1<<16) || b > (1<<16)) && (d = gcd(f, b)) > 1) {
459                     f /= d;
460                     b /= d;
461           }
462 
463 
464           while (f > (1<<16) || b > (1<<16)) {
465                     f /= 2;
466                     b /= 2;
467           }
468           if (f <= 0 || b <= 0)
469                     return -1;
470 
471 #ifdef    DIAGNOSTIC
472           err = divrnd(((uint64_t)imxuart_freq) * 1000 / imxuart_freqdiv,
473                          (uint64_t)speed * 16 * f / b) - 1000;
474           if (err < 0)
475                     err = -err;
476 #endif
477 
478           ratio->numerator = b-1;
479           ratio->modulator = f-1;
480 
481           if (err > IMXUART_TOLERANCE)
482                     return -1;
483 
484           return 0;
485 #undef    divrnd
486 }
487 
488 #ifdef IMXUART_DEBUG
489 int       imxuart_debug = 0;
490 
491 void imxustatus(struct imxuart_softc *, const char *);
492 void
imxustatus(struct imxuart_softc * sc,const char * str)493 imxustatus(struct imxuart_softc *sc, const char *str)
494 {
495           struct tty *tp = sc->sc_tty;
496 
497           aprint_normal_dev(sc->sc_dev,
498               "%s %cclocal  %cdcd %cts_carr_on %cdtr %ctx_stopped\n",
499               str,
500               ISSET(tp->t_cflag, CLOCAL) ? '+' : '-',
501               ISSET(sc->sc_msr, MSR_DCD) ? '+' : '-',
502               ISSET(tp->t_state, TS_CARR_ON) ? '+' : '-',
503               ISSET(sc->sc_mcr, MCR_DTR) ? '+' : '-',
504               sc->sc_tx_stopped ? '+' : '-');
505 
506           aprint_normal_dev(sc->sc_dev,
507               "%s %ccrtscts %ccts %cts_ttstop  %crts rx_flags=0x%x\n",
508               str,
509               ISSET(tp->t_cflag, CRTSCTS) ? '+' : '-',
510               ISSET(sc->sc_msr, MSR_CTS) ? '+' : '-',
511               ISSET(tp->t_state, TS_TTSTOP) ? '+' : '-',
512               ISSET(sc->sc_mcr, MCR_RTS) ? '+' : '-',
513               sc->sc_rx_flags);
514 }
515 #endif
516 
517 #if 0
518 int
519 imxuart_detach(device_t self, int flags)
520 {
521           struct imxuart_softc *sc = device_private(self);
522           int maj, mn;
523 
524         if (ISSET(sc->sc_hwflags, IMXUART_HW_CONSOLE))
525                     return EBUSY;
526 
527           /* locate the major number */
528           maj = cdevsw_lookup_major(&imxcom_cdevsw);
529 
530           /* Nuke the vnodes for any open instances. */
531           mn = device_unit(self);
532           vdevgone(maj, mn, mn, VCHR);
533 
534           mn |= IMXUART_DIALOUT_MASK;
535           vdevgone(maj, mn, mn, VCHR);
536 
537           if (sc->sc_rbuf == NULL) {
538                     /*
539                      * Ring buffer allocation failed in the imxuart_attach_subr,
540                      * only the tty is allocated, and nothing else.
541                      */
542                     tty_free(sc->sc_tty);
543                     return 0;
544           }
545 
546           /* Free the receive buffer. */
547           kmem_free(sc->sc_rbuf, sizeof(*sc->sc_rbuf) * sc->sc_rbuf_size);
548 
549           /* Detach and free the tty. */
550           tty_detach(sc->sc_tty);
551           tty_free(sc->sc_tty);
552 
553           /* Unhook the soft interrupt handler. */
554           softint_disestablish(sc->sc_si);
555 
556 #ifdef RND_COM
557           /* Unhook the entropy source. */
558           rnd_detach_source(&sc->rnd_source);
559 #endif
560           callout_destroy(&sc->sc_diag_callout);
561 
562           /* Destroy the lock. */
563           mutex_destroy(&sc->sc_lock);
564 
565           return (0);
566 }
567 #endif
568 
569 #ifdef notyet
570 int
imxuart_activate(device_t self,enum devact act)571 imxuart_activate(device_t self, enum devact act)
572 {
573           struct imxuart_softc *sc = device_private(self);
574           int rv = 0;
575 
576           switch (act) {
577           case DVACT_ACTIVATE:
578                     rv = EOPNOTSUPP;
579                     break;
580 
581           case DVACT_DEACTIVATE:
582                     if (sc->sc_hwflags & (IMXUART_HW_CONSOLE|IMXUART_HW_KGDB)) {
583                               rv = EBUSY;
584                               break;
585                     }
586 
587                     if (sc->disable != NULL && sc->enabled != 0) {
588                               (*sc->disable)(sc);
589                               sc->enabled = 0;
590                     }
591                     break;
592           }
593 
594           return (rv);
595 }
596 #endif
597 
598 void
imxuart_shutdown(struct imxuart_softc * sc)599 imxuart_shutdown(struct imxuart_softc *sc)
600 {
601           struct tty *tp = sc->sc_tty;
602 
603           mutex_spin_enter(&sc->sc_lock);
604 
605           /* If we were asserting flow control, then deassert it. */
606           SET(sc->sc_rx_flags, IMXUART_RX_IBUF_BLOCKED);
607           imxuart_hwiflow(sc);
608 
609           /* Clear any break condition set with TIOCSBRK. */
610           imxuart_break(sc, false);
611 
612           /*
613            * Hang up if necessary.  Wait a bit, so the other side has time to
614            * notice even if we immediately open the port again.
615            * Avoid tsleeping above splhigh().
616            */
617           if (ISSET(tp->t_cflag, HUPCL)) {
618                     imxuart_modem(sc, 0);
619                     mutex_spin_exit(&sc->sc_lock);
620                     /* XXX will only timeout */
621                     (void) kpause(ttclos, false, hz, NULL);
622                     mutex_spin_enter(&sc->sc_lock);
623           }
624 
625           /* Turn off interrupts. */
626           imxuart_disable_all_interrupts(sc);
627           /* re-enable recv interrupt for console or kgdb port */
628           imxuart_enable_debugport(sc);
629 
630           mutex_spin_exit(&sc->sc_lock);
631 
632 #ifdef    notyet
633           if (sc->disable) {
634 #ifdef DIAGNOSTIC
635                     if (!sc->enabled)
636                               panic("imxuart_shutdown: not enabled?");
637 #endif
638                     (*sc->disable)(sc);
639                     sc->enabled = 0;
640           }
641 #endif
642 }
643 
644 int
imxuopen(dev_t dev,int flag,int mode,struct lwp * l)645 imxuopen(dev_t dev, int flag, int mode, struct lwp *l)
646 {
647           struct imxuart_softc *sc;
648           struct tty *tp;
649           int s;
650           int error;
651 
652           sc = device_lookup_private(&imxuart_cd, IMXUART_UNIT(dev));
653           if (sc == NULL || !ISSET(sc->sc_hwflags, IMXUART_HW_DEV_OK) ||
654                     sc->sc_rbuf == NULL)
655                     return (ENXIO);
656 
657           if (!device_is_active(sc->sc_dev))
658                     return (ENXIO);
659 
660 #ifdef KGDB
661           /*
662            * If this is the kgdb port, no other use is permitted.
663            */
664           if (ISSET(sc->sc_hwflags, IMXUART_HW_KGDB))
665                     return (EBUSY);
666 #endif
667 
668           tp = sc->sc_tty;
669 
670           if (kauth_authorize_device_tty(l->l_cred, KAUTH_DEVICE_TTY_OPEN, tp))
671                     return (EBUSY);
672 
673           s = spltty();
674 
675           /*
676            * Do the following iff this is a first open.
677            */
678           if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
679                     struct termios t;
680 
681                     tp->t_dev = dev;
682 
683 
684 #ifdef notyet
685                     if (sc->enable) {
686                               if ((*sc->enable)(sc)) {
687                                         splx(s);
688                                         aprint_error_dev(sc->sc_dev,
689                                             "device enable failed\n");
690                                         return (EIO);
691                               }
692                               sc->enabled = 1;
693                     }
694 #endif
695 
696                     mutex_spin_enter(&sc->sc_lock);
697 
698                     imxuart_disable_all_interrupts(sc);
699 
700                     /* Fetch the current modem control status, needed later. */
701 
702 #ifdef    IMXUART_PPS
703                     /* Clear PPS capture state on first open. */
704                     mutex_spin_enter(&timecounter_lock);
705                     memset(&sc->sc_pps_state, 0, sizeof(sc->sc_pps_state));
706                     sc->sc_pps_state.ppscap = PPS_CAPTUREASSERT | PPS_CAPTURECLEAR;
707                     pps_init(&sc->sc_pps_state);
708                     mutex_spin_exit(&timecounter_lock);
709 #endif
710 
711                     mutex_spin_exit(&sc->sc_lock);
712 
713                     /*
714                      * Initialize the termios status to the defaults.  Add in the
715                      * sticky bits from TIOCSFLAGS.
716                      */
717                     if (ISSET(sc->sc_hwflags, IMXUART_HW_CONSOLE)) {
718                               t.c_ospeed = imxuconsrate;
719                               t.c_cflag = imxuconscflag;
720                     } else {
721                               t.c_ospeed = TTYDEF_SPEED;
722                               t.c_cflag = TTYDEF_CFLAG;
723                     }
724                     t.c_ispeed = t.c_ospeed;
725                     if (ISSET(sc->sc_swflags, TIOCFLAG_CLOCAL))
726                               SET(t.c_cflag, CLOCAL);
727                     if (ISSET(sc->sc_swflags, TIOCFLAG_CRTSCTS))
728                               SET(t.c_cflag, CRTSCTS);
729                     if (ISSET(sc->sc_swflags, TIOCFLAG_MDMBUF))
730                               SET(t.c_cflag, MDMBUF);
731                     /* Make sure imxuparam() will do something. */
732                     tp->t_ospeed = 0;
733                     (void) imxuparam(tp, &t);
734                     tp->t_iflag = TTYDEF_IFLAG;
735                     tp->t_oflag = TTYDEF_OFLAG;
736                     tp->t_lflag = TTYDEF_LFLAG;
737                     ttychars(tp);
738                     ttsetwater(tp);
739 
740                     mutex_spin_enter(&sc->sc_lock);
741 
742                     /*
743                      * Turn on DTR.  We must always do this, even if carrier is not
744                      * present, because otherwise we'd have to use TIOCSDTR
745                      * immediately after setting CLOCAL, which applications do not
746                      * expect.  We always assert DTR while the device is open
747                      * unless explicitly requested to deassert it.
748                      */
749                     imxuart_modem(sc, 1);
750 
751                     /* Clear the input ring, and unblock. */
752                     sc->sc_rbuf_in = sc->sc_rbuf_out = 0;
753                     imxuart_iflush(sc);
754                     CLR(sc->sc_rx_flags, IMXUART_RX_ANY_BLOCK);
755                     imxuart_hwiflow(sc);
756 
757                     /* Turn on interrupts. */
758                     imxuart_control_rxint(sc, true);
759 
760 #ifdef IMXUART_DEBUG
761                     if (imxuart_debug)
762                               imxustatus(sc, "imxuopen  ");
763 #endif
764 
765                     mutex_spin_exit(&sc->sc_lock);
766           }
767 
768           splx(s);
769 
770 #if 0
771           error = ttyopen(tp, IMXUART_DIALOUT(dev), ISSET(flag, O_NONBLOCK));
772 #else
773           error = ttyopen(tp, 1, ISSET(flag, O_NONBLOCK));
774 #endif
775           if (error)
776                     goto bad;
777 
778           error = (*tp->t_linesw->l_open)(dev, tp);
779           if (error)
780                     goto bad;
781 
782           return (0);
783 
784 bad:
785           if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
786                     /*
787                      * We failed to open the device, and nobody else had it opened.
788                      * Clean up the state as appropriate.
789                      */
790                     imxuart_shutdown(sc);
791           }
792 
793           return (error);
794 }
795 
796 int
imxuclose(dev_t dev,int flag,int mode,struct lwp * l)797 imxuclose(dev_t dev, int flag, int mode, struct lwp *l)
798 {
799           struct imxuart_softc *sc =
800               device_lookup_private(&imxuart_cd, IMXUART_UNIT(dev));
801           struct tty *tp = sc->sc_tty;
802 
803           /* XXX This is for cons.c. */
804           if (!ISSET(tp->t_state, TS_ISOPEN))
805                     return (0);
806 
807           (*tp->t_linesw->l_close)(tp, flag);
808           ttyclose(tp);
809 
810           if (IMXUART_ISALIVE(sc) == 0)
811                     return (0);
812 
813           if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
814                     /*
815                      * Although we got a last close, the device may still be in
816                      * use; e.g. if this was the dialout node, and there are still
817                      * processes waiting for carrier on the non-dialout node.
818                      */
819                     imxuart_shutdown(sc);
820           }
821 
822           return (0);
823 }
824 
825 int
imxuread(dev_t dev,struct uio * uio,int flag)826 imxuread(dev_t dev, struct uio *uio, int flag)
827 {
828           struct imxuart_softc *sc =
829               device_lookup_private(&imxuart_cd, IMXUART_UNIT(dev));
830           struct tty *tp = sc->sc_tty;
831 
832           if (IMXUART_ISALIVE(sc) == 0)
833                     return (EIO);
834 
835           return ((*tp->t_linesw->l_read)(tp, uio, flag));
836 }
837 
838 int
imxuwrite(dev_t dev,struct uio * uio,int flag)839 imxuwrite(dev_t dev, struct uio *uio, int flag)
840 {
841           struct imxuart_softc *sc =
842               device_lookup_private(&imxuart_cd, IMXUART_UNIT(dev));
843           struct tty *tp = sc->sc_tty;
844 
845           if (IMXUART_ISALIVE(sc) == 0)
846                     return (EIO);
847 
848           return ((*tp->t_linesw->l_write)(tp, uio, flag));
849 }
850 
851 int
imxupoll(dev_t dev,int events,struct lwp * l)852 imxupoll(dev_t dev, int events, struct lwp *l)
853 {
854           struct imxuart_softc *sc =
855               device_lookup_private(&imxuart_cd, IMXUART_UNIT(dev));
856           struct tty *tp = sc->sc_tty;
857 
858           if (IMXUART_ISALIVE(sc) == 0)
859                     return (POLLHUP);
860 
861           return ((*tp->t_linesw->l_poll)(tp, events, l));
862 }
863 
864 struct tty *
imxutty(dev_t dev)865 imxutty(dev_t dev)
866 {
867           struct imxuart_softc *sc =
868               device_lookup_private(&imxuart_cd, IMXUART_UNIT(dev));
869           struct tty *tp = sc->sc_tty;
870 
871           return (tp);
872 }
873 
874 int
imxuioctl(dev_t dev,u_long cmd,void * data,int flag,struct lwp * l)875 imxuioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l)
876 {
877           struct imxuart_softc *sc;
878           struct tty *tp;
879           int error;
880 
881           sc = device_lookup_private(&imxuart_cd, IMXUART_UNIT(dev));
882           if (sc == NULL)
883                     return ENXIO;
884           if (IMXUART_ISALIVE(sc) == 0)
885                     return (EIO);
886 
887           tp = sc->sc_tty;
888 
889           error = (*tp->t_linesw->l_ioctl)(tp, cmd, data, flag, l);
890           if (error != EPASSTHROUGH)
891                     return (error);
892 
893           error = ttioctl(tp, cmd, data, flag, l);
894           if (error != EPASSTHROUGH)
895                     return (error);
896 
897           error = 0;
898           switch (cmd) {
899           case TIOCSFLAGS:
900                     error = kauth_authorize_device_tty(l->l_cred,
901                         KAUTH_DEVICE_TTY_PRIVSET, tp);
902                     break;
903           default:
904                     /* nothing */
905                     break;
906           }
907           if (error) {
908                     return error;
909           }
910 
911           mutex_spin_enter(&sc->sc_lock);
912 
913           switch (cmd) {
914           case TIOCSBRK:
915                     imxuart_break(sc, true);
916                     break;
917 
918           case TIOCCBRK:
919                     imxuart_break(sc, false);
920                     break;
921 
922           case TIOCSDTR:
923                     imxuart_modem(sc, 1);
924                     break;
925 
926           case TIOCCDTR:
927                     imxuart_modem(sc, 0);
928                     break;
929 
930           case TIOCGFLAGS:
931                     *(int *)data = sc->sc_swflags;
932                     break;
933 
934           case TIOCSFLAGS:
935                     sc->sc_swflags = *(int *)data;
936                     break;
937 
938           case TIOCMSET:
939           case TIOCMBIS:
940           case TIOCMBIC:
941                     tiocm_to_imxu(sc, cmd, *(int *)data);
942                     break;
943 
944           case TIOCMGET:
945                     *(int *)data = imxuart_to_tiocm(sc);
946                     break;
947 
948 #ifdef notyet
949           case PPS_IOC_CREATE:
950           case PPS_IOC_DESTROY:
951           case PPS_IOC_GETPARAMS:
952           case PPS_IOC_SETPARAMS:
953           case PPS_IOC_GETCAP:
954           case PPS_IOC_FETCH:
955 #ifdef PPS_SYNC
956           case PPS_IOC_KCBIND:
957 #endif
958                     mutex_spin_enter(&timecounter_lock);
959                     error = pps_ioctl(cmd, data, &sc->sc_pps_state);
960                     mutex_spin_exit(&timecounter_lock);
961                     break;
962 
963           case TIOCDCDTIMESTAMP:        /* XXX old, overloaded  API used by xntpd v3 */
964                     mutex_spin_enter(&timecounter_lock);
965 #ifndef PPS_TRAILING_EDGE
966                     TIMESPEC_TO_TIMEVAL((struct timeval *)data,
967                         &sc->sc_pps_state.ppsinfo.assert_timestamp);
968 #else
969                     TIMESPEC_TO_TIMEVAL((struct timeval *)data,
970                         &sc->sc_pps_state.ppsinfo.clear_timestamp);
971 #endif
972                     mutex_spin_exit(&timecounter_lock);
973                     break;
974 #endif
975 
976           default:
977                     error = EPASSTHROUGH;
978                     break;
979           }
980 
981           mutex_spin_exit(&sc->sc_lock);
982 
983 #ifdef IMXUART_DEBUG
984           if (imxuart_debug)
985                     imxustatus(sc, "imxuioctl ");
986 #endif
987 
988           return (error);
989 }
990 
991 integrate void
imxuart_schedrx(struct imxuart_softc * sc)992 imxuart_schedrx(struct imxuart_softc *sc)
993 {
994           sc->sc_rx_ready = 1;
995 
996           /* Wake up the poller. */
997           softint_schedule(sc->sc_si);
998 }
999 
1000 void
imxuart_break(struct imxuart_softc * sc,bool onoff)1001 imxuart_break(struct imxuart_softc *sc, bool onoff)
1002 {
1003           bus_space_tag_t iot = sc->sc_regs.ur_iot;
1004           bus_space_handle_t ioh = sc->sc_regs.ur_ioh;
1005 
1006           if (onoff)
1007                     SET(sc->sc_ucr1, IMX_UCR1_SNDBRK);
1008           else
1009                     CLR(sc->sc_ucr1, IMX_UCR1_SNDBRK);
1010 
1011           bus_space_write_4(iot, ioh, IMX_UCR1, sc->sc_ucr1);
1012 }
1013 
1014 void
imxuart_modem(struct imxuart_softc * sc,int onoff)1015 imxuart_modem(struct imxuart_softc *sc, int onoff)
1016 {
1017 #ifdef notyet
1018           if (sc->sc_mcr_dtr == 0)
1019                     return;
1020 
1021           if (onoff)
1022                     SET(sc->sc_mcr, sc->sc_mcr_dtr);
1023           else
1024                     CLR(sc->sc_mcr, sc->sc_mcr_dtr);
1025 
1026           if (!sc->sc_heldchange) {
1027                     if (sc->sc_tx_busy) {
1028                               sc->sc_heldtbc = sc->sc_tbc;
1029                               sc->sc_tbc = 0;
1030                               sc->sc_heldchange = 1;
1031                     } else
1032                               imxuart_loadchannelregs(sc);
1033           }
1034 #endif
1035 }
1036 
1037 /*
1038  * RTS output is controlled by UCR2.CTS bit.
1039  * DTR output is controlled by UCR3.DSR bit.
1040  * (i.MX reference manual uses names in DCE mode)
1041  *
1042  * note: if UCR2.CTSC == 1 for automatic HW flow control, UCR2.CTS is ignored.
1043  */
1044 void
tiocm_to_imxu(struct imxuart_softc * sc,u_long how,int ttybits)1045 tiocm_to_imxu(struct imxuart_softc *sc, u_long how, int ttybits)
1046 {
1047           bus_space_tag_t iot = sc->sc_regs.ur_iot;
1048           bus_space_handle_t ioh = sc->sc_regs.ur_ioh;
1049 
1050           uint32_t ucr2 = sc->sc_ucr2_d;
1051           uint32_t ucr3 = sc->sc_ucr3;
1052 
1053           uint32_t ucr2_mask = 0;
1054           uint32_t ucr3_mask = 0;
1055 
1056 
1057           if (ISSET(ttybits, TIOCM_DTR))
1058                     ucr3_mask = IMX_UCR3_DSR;
1059           if (ISSET(ttybits, TIOCM_RTS))
1060                     ucr2_mask = IMX_UCR2_CTS;
1061 
1062           switch (how) {
1063           case TIOCMBIC:
1064                     CLR(ucr2, ucr2_mask);
1065                     CLR(ucr3, ucr3_mask);
1066                     break;
1067 
1068           case TIOCMBIS:
1069                     SET(ucr2, ucr2_mask);
1070                     SET(ucr3, ucr3_mask);
1071                     break;
1072 
1073           case TIOCMSET:
1074                     CLR(ucr2, ucr2_mask);
1075                     CLR(ucr3, ucr3_mask);
1076                     SET(ucr2, ucr2_mask);
1077                     SET(ucr3, ucr3_mask);
1078                     break;
1079           }
1080 
1081           if (ucr3 != sc->sc_ucr3) {
1082                     bus_space_write_4(iot, ioh, IMX_UCR3, ucr3);
1083                     sc->sc_ucr3 = ucr3;
1084           }
1085 
1086           if (ucr2 == sc->sc_ucr2_d)
1087                     return;
1088 
1089           sc->sc_ucr2_d = ucr2;
1090           /* update CTS bit only */
1091           ucr2 = (sc->sc_ucr2 & ~IMX_UCR2_CTS) |
1092               (ucr2 & IMX_UCR2_CTS);
1093 
1094           bus_space_write_4(iot, ioh, IMX_UCR2, ucr2);
1095           sc->sc_ucr2 = ucr2;
1096 }
1097 
1098 int
imxuart_to_tiocm(struct imxuart_softc * sc)1099 imxuart_to_tiocm(struct imxuart_softc *sc)
1100 {
1101           bus_space_tag_t iot = sc->sc_regs.ur_iot;
1102           bus_space_handle_t ioh = sc->sc_regs.ur_ioh;
1103           int ttybits = 0;
1104           uint32_t usr[2];
1105 
1106           if (ISSET(sc->sc_ucr3, IMX_UCR3_DSR))
1107                     SET(ttybits, TIOCM_DTR);
1108           if (ISSET(sc->sc_ucr2, IMX_UCR2_CTS))
1109                     SET(ttybits, TIOCM_RTS);
1110 
1111           bus_space_read_region_4(iot, ioh, IMX_USR1, usr, 2);
1112 
1113           if (ISSET(usr[0], IMX_USR1_RTSS))
1114                     SET(ttybits, TIOCM_CTS);
1115 
1116           if (ISSET(usr[1], IMX_USR2_DCDIN))
1117                     SET(ttybits, TIOCM_CD);
1118 
1119 #if 0
1120           /* XXXbsh: I couldn't find the way to read ipp_uart_dsr_dte_i signal,
1121              although there are bits in UART registers to detect delta of DSR.
1122           */
1123           if (ISSET(imxubits, MSR_DSR))
1124                     SET(ttybits, TIOCM_DSR);
1125 #endif
1126 
1127           if (ISSET(usr[1], IMX_USR2_RIIN))
1128                     SET(ttybits, TIOCM_RI);
1129 
1130 
1131 #ifdef    notyet
1132           if (ISSET(sc->sc_ier, IER_ERXRDY | IER_ETXRDY | IER_ERLS | IER_EMSC))
1133                     SET(ttybits, TIOCM_LE);
1134 #endif
1135 
1136           return (ttybits);
1137 }
1138 
1139 static uint32_t
cflag_to_ucr2(tcflag_t cflag,uint32_t oldval)1140 cflag_to_ucr2(tcflag_t cflag, uint32_t oldval)
1141 {
1142           uint32_t val = oldval;
1143 
1144           CLR(val,IMX_UCR2_WS|IMX_UCR2_PREN|IMX_UCR2_PROE|IMX_UCR2_STPB);
1145 
1146           switch (cflag & CSIZE) {
1147           case CS5:
1148           case CS6:
1149                     /* not suppreted. use 7-bits */
1150           case CS7:
1151                     break;
1152           case CS8:
1153                     SET(val, IMX_UCR2_WS);
1154                     break;
1155           }
1156 
1157 
1158           if (ISSET(cflag, PARENB)) {
1159                     SET(val, IMX_UCR2_PREN);
1160 
1161                     /* odd parity */
1162                     if (!ISSET(cflag, PARODD))
1163                               SET(val, IMX_UCR2_PROE);
1164           }
1165 
1166           if (ISSET(cflag, CSTOPB))
1167                     SET(val, IMX_UCR2_STPB);
1168 
1169           val |= IMX_UCR2_TXEN| IMX_UCR2_RXEN|IMX_UCR2_SRST;
1170 
1171           return val;
1172 }
1173 
1174 int
imxuparam(struct tty * tp,struct termios * t)1175 imxuparam(struct tty *tp, struct termios *t)
1176 {
1177           struct imxuart_softc *sc =
1178               device_lookup_private(&imxuart_cd, IMXUART_UNIT(tp->t_dev));
1179           struct imxuart_baudrate_ratio ratio;
1180           uint32_t ucr2;
1181           bool change_speed = tp->t_ospeed != t->c_ospeed;
1182 
1183           if (IMXUART_ISALIVE(sc) == 0)
1184                     return (EIO);
1185 
1186           /* Check requested parameters. */
1187           if (t->c_ispeed && t->c_ispeed != t->c_ospeed)
1188                     return (EINVAL);
1189 
1190           /*
1191            * For the console, always force CLOCAL and !HUPCL, so that the port
1192            * is always active.
1193            */
1194           if (ISSET(sc->sc_swflags, TIOCFLAG_SOFTCAR) ||
1195               ISSET(sc->sc_hwflags, IMXUART_HW_CONSOLE)) {
1196                     SET(t->c_cflag, CLOCAL);
1197                     CLR(t->c_cflag, HUPCL);
1198           }
1199 
1200           /*
1201            * If there were no changes, don't do anything.  This avoids dropping
1202            * input and improves performance when all we did was frob things like
1203            * VMIN and VTIME.
1204            */
1205           if ( !change_speed && tp->t_cflag == t->c_cflag)
1206                     return (0);
1207 
1208           if (change_speed) {
1209                     /* calculate baudrate modulator value */
1210                     if (imxuspeed(t->c_ospeed, &ratio) < 0)
1211                               return (EINVAL);
1212                     sc->sc_ratio = ratio;
1213           }
1214 
1215           ucr2 = cflag_to_ucr2(t->c_cflag, sc->sc_ucr2_d);
1216 
1217           mutex_spin_enter(&sc->sc_lock);
1218 
1219 #if 0     /* flow control stuff.  not yet */
1220           /*
1221            * If we're not in a mode that assumes a connection is present, then
1222            * ignore carrier changes.
1223            */
1224           if (ISSET(t->c_cflag, CLOCAL | MDMBUF))
1225                     sc->sc_msr_dcd = 0;
1226           else
1227                     sc->sc_msr_dcd = MSR_DCD;
1228           /*
1229            * Set the flow control pins depending on the current flow control
1230            * mode.
1231            */
1232           if (ISSET(t->c_cflag, CRTSCTS)) {
1233                     sc->sc_mcr_dtr = MCR_DTR;
1234                     sc->sc_mcr_rts = MCR_RTS;
1235                     sc->sc_msr_cts = MSR_CTS;
1236                     sc->sc_efr = EFR_AUTORTS | EFR_AUTOCTS;
1237           } else if (ISSET(t->c_cflag, MDMBUF)) {
1238                     /*
1239                      * For DTR/DCD flow control, make sure we don't toggle DTR for
1240                      * carrier detection.
1241                      */
1242                     sc->sc_mcr_dtr = 0;
1243                     sc->sc_mcr_rts = MCR_DTR;
1244                     sc->sc_msr_cts = MSR_DCD;
1245                     sc->sc_efr = 0;
1246           } else {
1247                     /*
1248                      * If no flow control, then always set RTS.  This will make
1249                      * the other side happy if it mistakenly thinks we're doing
1250                      * RTS/CTS flow control.
1251                      */
1252                     sc->sc_mcr_dtr = MCR_DTR | MCR_RTS;
1253                     sc->sc_mcr_rts = 0;
1254                     sc->sc_msr_cts = 0;
1255                     sc->sc_efr = 0;
1256                     if (ISSET(sc->sc_mcr, MCR_DTR))
1257                               SET(sc->sc_mcr, MCR_RTS);
1258                     else
1259                               CLR(sc->sc_mcr, MCR_RTS);
1260           }
1261           sc->sc_msr_mask = sc->sc_msr_cts | sc->sc_msr_dcd;
1262 #endif
1263 
1264           /* And copy to tty. */
1265           tp->t_ispeed = t->c_ospeed;
1266           tp->t_ospeed = t->c_ospeed;
1267           tp->t_cflag = t->c_cflag;
1268 
1269           if (!change_speed && ucr2 == sc->sc_ucr2_d) {
1270                     /* noop */
1271           }
1272           else if (!sc->sc_pending && !sc->sc_tx_busy) {
1273                     if (ucr2 != sc->sc_ucr2_d) {
1274                               sc->sc_ucr2_d = ucr2;
1275                               imxuart_load_params(sc);
1276                     }
1277                     if (change_speed)
1278                               imxuart_load_speed(sc);
1279           }
1280           else {
1281                     if (!sc->sc_pending) {
1282                               sc->sc_heldtbc = sc->sc_tbc;
1283                               sc->sc_tbc = 0;
1284                     }
1285                     sc->sc_pending |=
1286                         (ucr2 == sc->sc_ucr2_d ? 0 : IMXUART_PEND_PARAM) |
1287                         (change_speed ? 0 : IMXUART_PEND_SPEED);
1288                     sc->sc_ucr2_d = ucr2;
1289           }
1290 
1291           if (!ISSET(t->c_cflag, CHWFLOW)) {
1292                     /* Disable the high water mark. */
1293                     sc->sc_r_hiwat = 0;
1294                     sc->sc_r_lowat = 0;
1295                     if (ISSET(sc->sc_rx_flags, IMXUART_RX_TTY_OVERFLOWED)) {
1296                               CLR(sc->sc_rx_flags, IMXUART_RX_TTY_OVERFLOWED);
1297                               imxuart_schedrx(sc);
1298                     }
1299                     if (ISSET(sc->sc_rx_flags,
1300                               IMXUART_RX_TTY_BLOCKED|IMXUART_RX_IBUF_BLOCKED)) {
1301                               CLR(sc->sc_rx_flags,
1302                                   IMXUART_RX_TTY_BLOCKED|IMXUART_RX_IBUF_BLOCKED);
1303                               imxuart_hwiflow(sc);
1304                     }
1305           } else {
1306                     sc->sc_r_hiwat = imxuart_rbuf_hiwat;
1307                     sc->sc_r_lowat = imxuart_rbuf_lowat;
1308           }
1309 
1310           mutex_spin_exit(&sc->sc_lock);
1311 
1312 #if 0
1313           /*
1314            * Update the tty layer's idea of the carrier bit, in case we changed
1315            * CLOCAL or MDMBUF.  We don't hang up here; we only do that by
1316            * explicit request.
1317            */
1318           (void) (*tp->t_linesw->l_modem)(tp, ISSET(sc->sc_msr, MSR_DCD));
1319 #else
1320           /* XXX: always report that we have DCD */
1321           (void) (*tp->t_linesw->l_modem)(tp, 1);
1322 #endif
1323 
1324 #ifdef IMXUART_DEBUG
1325           if (imxuart_debug)
1326                     imxustatus(sc, "imxuparam ");
1327 #endif
1328 
1329           if (!ISSET(t->c_cflag, CHWFLOW)) {
1330                     if (sc->sc_tx_stopped) {
1331                               sc->sc_tx_stopped = 0;
1332                               imxustart(tp);
1333                     }
1334           }
1335 
1336           return (0);
1337 }
1338 
1339 void
imxuart_iflush(struct imxuart_softc * sc)1340 imxuart_iflush(struct imxuart_softc *sc)
1341 {
1342           bus_space_tag_t iot = sc->sc_regs.ur_iot;
1343           bus_space_handle_t ioh = sc->sc_regs.ur_ioh;
1344 #ifdef DIAGNOSTIC
1345           uint32_t reg = 0xffff;
1346 #endif
1347           int timo;
1348 
1349           timo = 50000;
1350           /* flush any pending I/O */
1351           while (ISSET(bus_space_read_4(iot, ioh, IMX_USR2), IMX_USR2_RDR)
1352               && --timo)
1353 #ifdef DIAGNOSTIC
1354                     reg =
1355 #else
1356                         (void)
1357 #endif
1358                         bus_space_read_4(iot, ioh, IMX_URXD);
1359 #ifdef DIAGNOSTIC
1360           if (!timo)
1361                     aprint_error_dev(sc->sc_dev, "imxuart_iflush timeout %02x\n", reg);
1362 #endif
1363 }
1364 
1365 int
imxuhwiflow(struct tty * tp,int block)1366 imxuhwiflow(struct tty *tp, int block)
1367 {
1368           struct imxuart_softc *sc =
1369               device_lookup_private(&imxuart_cd, IMXUART_UNIT(tp->t_dev));
1370 
1371           if (IMXUART_ISALIVE(sc) == 0)
1372                     return (0);
1373 
1374 #ifdef notyet
1375           if (sc->sc_mcr_rts == 0)
1376                     return (0);
1377 #endif
1378 
1379           mutex_spin_enter(&sc->sc_lock);
1380 
1381           if (block) {
1382                     if (!ISSET(sc->sc_rx_flags, IMXUART_RX_TTY_BLOCKED)) {
1383                               SET(sc->sc_rx_flags, IMXUART_RX_TTY_BLOCKED);
1384                               imxuart_hwiflow(sc);
1385                     }
1386           } else {
1387                     if (ISSET(sc->sc_rx_flags, IMXUART_RX_TTY_OVERFLOWED)) {
1388                               CLR(sc->sc_rx_flags, IMXUART_RX_TTY_OVERFLOWED);
1389                               imxuart_schedrx(sc);
1390                     }
1391                     if (ISSET(sc->sc_rx_flags, IMXUART_RX_TTY_BLOCKED)) {
1392                               CLR(sc->sc_rx_flags, IMXUART_RX_TTY_BLOCKED);
1393                               imxuart_hwiflow(sc);
1394                     }
1395           }
1396 
1397           mutex_spin_exit(&sc->sc_lock);
1398           return (1);
1399 }
1400 
1401 /*
1402  * (un)block input via hw flowcontrol
1403  */
1404 void
imxuart_hwiflow(struct imxuart_softc * sc)1405 imxuart_hwiflow(struct imxuart_softc *sc)
1406 {
1407 #ifdef notyet
1408           struct imxuart_regs *regsp= &sc->sc_regs;
1409 
1410           if (sc->sc_mcr_rts == 0)
1411                     return;
1412 
1413           if (ISSET(sc->sc_rx_flags, RX_ANY_BLOCK)) {
1414                     CLR(sc->sc_mcr, sc->sc_mcr_rts);
1415                     CLR(sc->sc_mcr_active, sc->sc_mcr_rts);
1416           } else {
1417                     SET(sc->sc_mcr, sc->sc_mcr_rts);
1418                     SET(sc->sc_mcr_active, sc->sc_mcr_rts);
1419           }
1420           UR_WRITE_1(regsp, IMXUART_REG_MCR, sc->sc_mcr_active);
1421 #endif
1422 }
1423 
1424 
1425 void
imxustart(struct tty * tp)1426 imxustart(struct tty *tp)
1427 {
1428           struct imxuart_softc *sc =
1429               device_lookup_private(&imxuart_cd, IMXUART_UNIT(tp->t_dev));
1430           int s;
1431           u_char *tba;
1432           int tbc;
1433           u_int n;
1434           u_int space;
1435           bus_space_tag_t iot = sc->sc_regs.ur_iot;
1436           bus_space_handle_t ioh = sc->sc_regs.ur_ioh;
1437 
1438           if (IMXUART_ISALIVE(sc) == 0)
1439                     return;
1440 
1441           s = spltty();
1442           if (ISSET(tp->t_state, TS_BUSY | TS_TIMEOUT | TS_TTSTOP))
1443                     goto out;
1444           if (sc->sc_tx_stopped)
1445                     goto out;
1446           if (!ttypull(tp))
1447                     goto out;
1448 
1449           /* Grab the first contiguous region of buffer space. */
1450           tba = tp->t_outq.c_cf;
1451           tbc = ndqb(&tp->t_outq, 0);
1452 
1453           mutex_spin_enter(&sc->sc_lock);
1454 
1455           sc->sc_tba = tba;
1456           sc->sc_tbc = tbc;
1457 
1458           SET(tp->t_state, TS_BUSY);
1459           sc->sc_tx_busy = 1;
1460 
1461           space = imxuart_txfifo_space(sc);
1462           n = MIN(sc->sc_tbc, space);
1463 
1464           if (n > 0) {
1465                     bus_space_write_multi_1(iot, ioh, IMX_UTXD, sc->sc_tba, n);
1466                     sc->sc_tbc -= n;
1467                     sc->sc_tba += n;
1468           }
1469 
1470           /* Enable transmit completion interrupts */
1471           imxuart_control_txint(sc, true);
1472 
1473           mutex_spin_exit(&sc->sc_lock);
1474 out:
1475           splx(s);
1476           return;
1477 }
1478 
1479 /*
1480  * Stop output on a line.
1481  */
1482 void
imxustop(struct tty * tp,int flag)1483 imxustop(struct tty *tp, int flag)
1484 {
1485           struct imxuart_softc *sc =
1486               device_lookup_private(&imxuart_cd, IMXUART_UNIT(tp->t_dev));
1487 
1488           mutex_spin_enter(&sc->sc_lock);
1489           if (ISSET(tp->t_state, TS_BUSY)) {
1490                     /* Stop transmitting at the next chunk. */
1491                     sc->sc_tbc = 0;
1492                     sc->sc_heldtbc = 0;
1493                     if (!ISSET(tp->t_state, TS_TTSTOP))
1494                               SET(tp->t_state, TS_FLUSH);
1495           }
1496           mutex_spin_exit(&sc->sc_lock);
1497 }
1498 
1499 void
imxudiag(void * arg)1500 imxudiag(void *arg)
1501 {
1502 #ifdef notyet
1503           struct imxuart_softc *sc = arg;
1504           int overflows, floods;
1505 
1506           mutex_spin_enter(&sc->sc_lock);
1507           overflows = sc->sc_overflows;
1508           sc->sc_overflows = 0;
1509           floods = sc->sc_floods;
1510           sc->sc_floods = 0;
1511           sc->sc_errors = 0;
1512           mutex_spin_exit(&sc->sc_lock);
1513 
1514           log(LOG_WARNING, "%s: %d silo overflow%s, %d ibuf flood%s\n",
1515               device_xname(sc->sc_dev),
1516               overflows, overflows == 1 ? "" : "s",
1517               floods, floods == 1 ? "" : "s");
1518 #endif
1519 }
1520 
1521 integrate void
imxuart_rxsoft(struct imxuart_softc * sc,struct tty * tp)1522 imxuart_rxsoft(struct imxuart_softc *sc, struct tty *tp)
1523 {
1524           int (*rint)(int, struct tty *) = tp->t_linesw->l_rint;
1525           u_int cc, scc, outp;
1526           uint16_t data;
1527           u_int code;
1528 
1529           scc = cc = IMXUART_RBUF_AVAIL(sc);
1530 
1531 #if 0
1532           if (cc == imxuart_rbuf_size-1) {
1533                     sc->sc_floods++;
1534                     if (sc->sc_errors++ == 0)
1535                               callout_reset(&sc->sc_diag_callout, 60 * hz,
1536                                   imxudiag, sc);
1537           }
1538 #endif
1539 
1540           /* If not yet open, drop the entire buffer content here */
1541           if (!ISSET(tp->t_state, TS_ISOPEN)) {
1542                     sc->sc_rbuf_out = sc->sc_rbuf_in;
1543                     cc = 0;
1544           }
1545 
1546           outp = sc->sc_rbuf_out;
1547 
1548 #define   ERRBITS (IMX_URXD_PRERR|IMX_URXD_BRK|IMX_URXD_FRMERR|IMX_URXD_OVRRUN)
1549 
1550           while (cc) {
1551                   data = sc->sc_rbuf[outp];
1552                     code = data & IMX_URXD_RX_DATA;
1553                     if (ISSET(data, ERRBITS)) {
1554                               if (sc->sc_errors.err == 0)
1555                                         callout_reset(&sc->sc_diag_callout,
1556                                             60 * hz, imxudiag, sc);
1557                               if (ISSET(data, IMX_URXD_OVRRUN))
1558                                         sc->sc_errors.ovrrun++;
1559                               if (ISSET(data, IMX_URXD_BRK)) {
1560                                         sc->sc_errors.brk++;
1561                                         SET(code, TTY_FE);
1562                               }
1563                               if (ISSET(data, IMX_URXD_FRMERR)) {
1564                                         sc->sc_errors.frmerr++;
1565                                         SET(code, TTY_FE);
1566                               }
1567                               if (ISSET(data, IMX_URXD_PRERR)) {
1568                                         sc->sc_errors.prerr++;
1569                                         SET(code, TTY_PE);
1570                               }
1571                     }
1572                     if ((*rint)(code, tp) == -1) {
1573                               /*
1574                                * The line discipline's buffer is out of space.
1575                                */
1576                               if (!ISSET(sc->sc_rx_flags, IMXUART_RX_TTY_BLOCKED)) {
1577                                         /*
1578                                          * We're either not using flow control, or the
1579                                          * line discipline didn't tell us to block for
1580                                          * some reason.  Either way, we have no way to
1581                                          * know when there's more space available, so
1582                                          * just drop the rest of the data.
1583                                          */
1584                                         sc->sc_rbuf_out = sc->sc_rbuf_in;
1585                                         cc = 0;
1586                               } else {
1587                                         /*
1588                                          * Don't schedule any more receive processing
1589                                          * until the line discipline tells us there's
1590                                          * space available (through imxuhwiflow()).
1591                                          * Leave the rest of the data in the input
1592                                          * buffer.
1593                                          */
1594                                         SET(sc->sc_rx_flags, IMXUART_RX_TTY_OVERFLOWED);
1595                               }
1596                               break;
1597                     }
1598                     outp = IMXUART_RBUF_INC(sc, outp, 1);
1599                     cc--;
1600           }
1601 
1602           if (cc != scc) {
1603                     sc->sc_rbuf_out = outp;
1604                     mutex_spin_enter(&sc->sc_lock);
1605 
1606                     cc = IMXUART_RBUF_SPACE(sc);
1607 
1608                     /* Buffers should be ok again, release possible block. */
1609                     if (cc >= sc->sc_r_lowat) {
1610                               if (ISSET(sc->sc_rx_flags, IMXUART_RX_IBUF_OVERFLOWED)) {
1611                                         CLR(sc->sc_rx_flags, IMXUART_RX_IBUF_OVERFLOWED);
1612                                         imxuart_control_rxint(sc, true);
1613                               }
1614                               if (ISSET(sc->sc_rx_flags, IMXUART_RX_IBUF_BLOCKED)) {
1615                                         CLR(sc->sc_rx_flags, IMXUART_RX_IBUF_BLOCKED);
1616                                         imxuart_hwiflow(sc);
1617                               }
1618                     }
1619                     mutex_spin_exit(&sc->sc_lock);
1620           }
1621 }
1622 
1623 integrate void
imxuart_txsoft(struct imxuart_softc * sc,struct tty * tp)1624 imxuart_txsoft(struct imxuart_softc *sc, struct tty *tp)
1625 {
1626 
1627           CLR(tp->t_state, TS_BUSY);
1628           if (ISSET(tp->t_state, TS_FLUSH))
1629                     CLR(tp->t_state, TS_FLUSH);
1630           else
1631                     ndflush(&tp->t_outq, (int)(sc->sc_tba - tp->t_outq.c_cf));
1632           (*tp->t_linesw->l_start)(tp);
1633 }
1634 
1635 integrate void
imxuart_stsoft(struct imxuart_softc * sc,struct tty * tp)1636 imxuart_stsoft(struct imxuart_softc *sc, struct tty *tp)
1637 {
1638 #ifdef notyet
1639           u_char msr, delta;
1640 
1641           mutex_spin_enter(&sc->sc_lock);
1642           msr = sc->sc_msr;
1643           delta = sc->sc_msr_delta;
1644           sc->sc_msr_delta = 0;
1645           mutex_spin_exit(&sc->sc_lock);
1646 
1647           if (ISSET(delta, sc->sc_msr_dcd)) {
1648                     /*
1649                      * Inform the tty layer that carrier detect changed.
1650                      */
1651                     (void) (*tp->t_linesw->l_modem)(tp, ISSET(msr, MSR_DCD));
1652           }
1653 
1654           if (ISSET(delta, sc->sc_msr_cts)) {
1655                     /* Block or unblock output according to flow control. */
1656                     if (ISSET(msr, sc->sc_msr_cts)) {
1657                               sc->sc_tx_stopped = 0;
1658                               (*tp->t_linesw->l_start)(tp);
1659                     } else {
1660                               sc->sc_tx_stopped = 1;
1661                     }
1662           }
1663 
1664 #endif
1665 #ifdef IMXUART_DEBUG
1666           if (imxuart_debug)
1667                     imxustatus(sc, "imxuart_stsoft");
1668 #endif
1669 }
1670 
1671 void
imxusoft(void * arg)1672 imxusoft(void *arg)
1673 {
1674           struct imxuart_softc *sc = arg;
1675           struct tty *tp;
1676 
1677           if (IMXUART_ISALIVE(sc) == 0)
1678                     return;
1679 
1680           tp = sc->sc_tty;
1681 
1682           if (sc->sc_rx_ready) {
1683                     sc->sc_rx_ready = 0;
1684                     imxuart_rxsoft(sc, tp);
1685           }
1686 
1687           if (sc->sc_st_check) {
1688                     sc->sc_st_check = 0;
1689                     imxuart_stsoft(sc, tp);
1690           }
1691 
1692           if (sc->sc_tx_done) {
1693                     sc->sc_tx_done = 0;
1694                     imxuart_txsoft(sc, tp);
1695           }
1696 }
1697 
1698 int
imxuintr(void * arg)1699 imxuintr(void *arg)
1700 {
1701           struct imxuart_softc *sc = arg;
1702           uint32_t usr1, usr2;
1703           bus_space_tag_t iot = sc->sc_regs.ur_iot;
1704           bus_space_handle_t ioh = sc->sc_regs.ur_ioh;
1705 
1706 
1707           if (IMXUART_ISALIVE(sc) == 0)
1708                     return (0);
1709 
1710           mutex_spin_enter(&sc->sc_lock);
1711 
1712           usr2 = bus_space_read_4(iot, ioh, IMX_USR2);
1713 
1714 
1715           do {
1716                     bus_space_write_4(iot, ioh, IMX_USR2,
1717                         usr2 & (IMX_USR2_BRCD|IMX_USR2_ORE));
1718                     if (usr2 & IMX_USR2_BRCD) {
1719                               /* Break signal detected */
1720                               int cn_trapped = 0;
1721 
1722                               cn_check_magic(sc->sc_tty->t_dev,
1723                                                CNC_BREAK, imxuart_cnm_state);
1724                               if (cn_trapped)
1725                                         goto next;
1726 #if defined(KGDB) && !defined(DDB)
1727                               if (ISSET(sc->sc_hwflags, IMXUART_HW_KGDB)) {
1728                                         kgdb_connect(1);
1729                                         goto next;
1730                               }
1731 #endif
1732                     }
1733 
1734                     if (usr2 & IMX_USR2_RDR)
1735                               imxuintr_read(sc);
1736 
1737 #ifdef    IMXUART_PPS
1738                     {
1739                               u_char    msr, delta;
1740 
1741                               msr = CSR_READ_1(regsp, IMXUART_REG_MSR);
1742                               delta = msr ^ sc->sc_msr;
1743                               sc->sc_msr = msr;
1744                               if ((sc->sc_pps_state.ppsparam.mode & PPS_CAPTUREBOTH) &&
1745                                   (delta & MSR_DCD)) {
1746                                         mutex_spin_enter(&timecounter_lock);
1747                                         pps_capture(&sc->sc_pps_state);
1748                                         pps_event(&sc->sc_pps_state,
1749                                             (msr & MSR_DCD) ?
1750                                             PPS_CAPTUREASSERT :
1751                                             PPS_CAPTURECLEAR);
1752                                         mutex_spin_exit(&timecounter_lock);
1753                               }
1754                     }
1755 #endif
1756 
1757 #ifdef notyet
1758                     /*
1759                      * Process normal status changes
1760                      */
1761                     if (ISSET(delta, sc->sc_msr_mask)) {
1762                               SET(sc->sc_msr_delta, delta);
1763 
1764                               /*
1765                                * Stop output immediately if we lose the output
1766                                * flow control signal or carrier detect.
1767                                */
1768                               if (ISSET(~msr, sc->sc_msr_mask)) {
1769                                         sc->sc_tbc = 0;
1770                                         sc->sc_heldtbc = 0;
1771 #ifdef IMXUART_DEBUG
1772                                         if (imxuart_debug)
1773                                                   imxustatus(sc, "imxuintr  ");
1774 #endif
1775                               }
1776 
1777                               sc->sc_st_check = 1;
1778                     }
1779 #endif
1780 
1781 next:
1782                     usr2 = bus_space_read_4(iot, ioh, IMX_USR2);
1783           } while (usr2 & (IMX_USR2_RDR|IMX_USR2_BRCD));
1784 
1785           usr1 = bus_space_read_4(iot, ioh, IMX_USR1);
1786           if (usr1 & IMX_USR1_TRDY)
1787                     imxuintr_send(sc);
1788 
1789           mutex_spin_exit(&sc->sc_lock);
1790 
1791           /* Wake up the poller. */
1792           softint_schedule(sc->sc_si);
1793 
1794 #ifdef RND_COM
1795           rnd_add_uint32(&sc->rnd_source, iir | lsr);
1796 #endif
1797 
1798           return (1);
1799 }
1800 
1801 
1802 /*
1803  * called when there is least one character in rxfifo
1804  *
1805  */
1806 
1807 static void
imxuintr_read(struct imxuart_softc * sc)1808 imxuintr_read(struct imxuart_softc *sc)
1809 {
1810           int cc;
1811           uint16_t rd;
1812           uint32_t usr2;
1813           bus_space_tag_t iot = sc->sc_regs.ur_iot;
1814           bus_space_handle_t ioh = sc->sc_regs.ur_ioh;
1815 
1816           cc = IMXUART_RBUF_SPACE(sc);
1817 
1818           /* clear aging timer interrupt */
1819           bus_space_write_4(iot, ioh, IMX_USR1, IMX_USR1_AGTIM);
1820 
1821           while (cc > 0) {
1822                     int cn_trapped = 0;
1823 
1824                     sc->sc_rbuf[sc->sc_rbuf_in] = rd =
1825                         bus_space_read_4(iot, ioh, IMX_URXD);
1826 
1827                     cn_check_magic(sc->sc_tty->t_dev,
1828                         rd & 0xff, imxuart_cnm_state);
1829 
1830                     if (!cn_trapped) {
1831 #if defined(DDB) && defined(DDB_KEYCODE)
1832                               /*
1833                                * Temporary hack so that I can force the kernel into
1834                                * the debugger via the serial port
1835                                */
1836                               if ((rd & 0xff) == DDB_KEYCODE)
1837                                         Debugger();
1838 #endif
1839                               sc->sc_rbuf_in = IMXUART_RBUF_INC(sc, sc->sc_rbuf_in, 1);
1840                               cc--;
1841                     }
1842 
1843                     usr2 = bus_space_read_4(iot, ioh, IMX_USR2);
1844                     if (!(usr2 & IMX_USR2_RDR))
1845                               break;
1846           }
1847 
1848           /*
1849            * Current string of incoming characters ended because
1850            * no more data was available or we ran out of space.
1851            * Schedule a receive event if any data was received.
1852            * If we're out of space, turn off receive interrupts.
1853            */
1854           if (!ISSET(sc->sc_rx_flags, IMXUART_RX_TTY_OVERFLOWED))
1855                     sc->sc_rx_ready = 1;
1856           /*
1857            * See if we are in danger of overflowing a buffer. If
1858            * so, use hardware flow control to ease the pressure.
1859            */
1860           if (!ISSET(sc->sc_rx_flags, IMXUART_RX_IBUF_BLOCKED) &&
1861               cc < sc->sc_r_hiwat) {
1862                     sc->sc_rx_flags |= IMXUART_RX_IBUF_BLOCKED;
1863                     imxuart_hwiflow(sc);
1864           }
1865 
1866           /*
1867            * If we're out of space, disable receive interrupts
1868            * until the queue has drained a bit.
1869            */
1870           if (!cc) {
1871                     sc->sc_rx_flags |= IMXUART_RX_IBUF_OVERFLOWED;
1872                     imxuart_control_rxint(sc, false);
1873           }
1874 }
1875 
1876 
1877 
1878 /*
1879  * find how many chars we can put into tx-fifo
1880  */
1881 static u_int
imxuart_txfifo_space(struct imxuart_softc * sc)1882 imxuart_txfifo_space(struct imxuart_softc *sc)
1883 {
1884           uint32_t usr1, usr2;
1885           u_int cc;
1886           bus_space_tag_t iot = sc->sc_regs.ur_iot;
1887           bus_space_handle_t ioh = sc->sc_regs.ur_ioh;
1888 
1889           usr2 = bus_space_read_4(iot, ioh, IMX_USR2);
1890           if (usr2 & IMX_USR2_TXFE)
1891                     cc = sc->sc_txfifo_len;
1892           else {
1893                     usr1 = bus_space_read_4(iot, ioh, IMX_USR1);
1894                     if (usr1 & IMX_USR1_TRDY)
1895                               cc = sc->sc_txfifo_thresh;
1896                     else
1897                               cc = 0;
1898           }
1899 
1900           return cc;
1901 }
1902 
1903 void
imxuintr_send(struct imxuart_softc * sc)1904 imxuintr_send(struct imxuart_softc *sc)
1905 {
1906           uint32_t usr2;
1907           bus_space_tag_t iot = sc->sc_regs.ur_iot;
1908           bus_space_handle_t ioh = sc->sc_regs.ur_ioh;
1909           int cc = 0;
1910 
1911           usr2 = bus_space_read_4(iot, ioh, IMX_USR2);
1912 
1913           if (sc->sc_pending) {
1914                     if (usr2 & IMX_USR2_TXFE) {
1915                               imxuart_load_pendings(sc);
1916                               sc->sc_tbc = sc->sc_heldtbc;
1917                               sc->sc_heldtbc = 0;
1918                     }
1919                     else {
1920                               /* wait for TX fifo empty */
1921                               imxuart_control_txint(sc, true);
1922                               return;
1923                     }
1924           }
1925 
1926           cc = imxuart_txfifo_space(sc);
1927           cc = MIN(cc, sc->sc_tbc);
1928 
1929           if (cc > 0) {
1930                     bus_space_write_multi_1(iot, ioh, IMX_UTXD, sc->sc_tba, cc);
1931                     sc->sc_tbc -= cc;
1932                     sc->sc_tba += cc;
1933           }
1934 
1935           if (sc->sc_tbc > 0)
1936                     imxuart_control_txint(sc, true);
1937           else {
1938                     /* no more chars to send.
1939                        we don't need tx interrupt any more. */
1940                     imxuart_control_txint(sc, false);
1941                     if (sc->sc_tx_busy) {
1942                               sc->sc_tx_busy = 0;
1943                               sc->sc_tx_done = 1;
1944                     }
1945           }
1946 }
1947 
1948 static void
imxuart_disable_all_interrupts(struct imxuart_softc * sc)1949 imxuart_disable_all_interrupts(struct imxuart_softc *sc)
1950 {
1951           bus_space_tag_t iot = sc->sc_regs.ur_iot;
1952           bus_space_handle_t ioh = sc->sc_regs.ur_ioh;
1953 
1954           sc->sc_ucr1 &= ~IMXUART_INTRS_UCR1;
1955           sc->sc_ucr2 &= ~IMXUART_INTRS_UCR2;
1956           sc->sc_ucr3 &= ~IMXUART_INTRS_UCR3;
1957           sc->sc_ucr4 &= ~IMXUART_INTRS_UCR4;
1958 
1959 
1960           bus_space_write_region_4(iot, ioh, IMX_UCR1, sc->sc_ucr, 4);
1961 }
1962 
1963 static void
imxuart_control_rxint(struct imxuart_softc * sc,bool enable)1964 imxuart_control_rxint(struct imxuart_softc *sc, bool enable)
1965 {
1966           bus_space_tag_t iot = sc->sc_regs.ur_iot;
1967           bus_space_handle_t ioh = sc->sc_regs.ur_ioh;
1968           uint32_t ucr1, ucr2;
1969 
1970           ucr1 = sc->sc_ucr1;
1971           ucr2 = sc->sc_ucr2;
1972 
1973           if (enable) {
1974                     ucr1 |= IMX_UCR1_RRDYEN;
1975                     ucr2 |= IMX_UCR2_ATEN;
1976           }
1977           else {
1978                     ucr1 &= ~IMX_UCR1_RRDYEN;
1979                     ucr2 &= ~IMX_UCR2_ATEN;
1980           }
1981 
1982           if (ucr1 != sc->sc_ucr1 || ucr2 != sc->sc_ucr2) {
1983                     sc->sc_ucr1 = ucr1;
1984                     sc->sc_ucr2 = ucr2;
1985                     bus_space_write_region_4(iot, ioh, IMX_UCR1, sc->sc_ucr, 2);
1986           }
1987 }
1988 
1989 static void
imxuart_control_txint(struct imxuart_softc * sc,bool enable)1990 imxuart_control_txint(struct imxuart_softc *sc, bool enable)
1991 {
1992           bus_space_tag_t iot = sc->sc_regs.ur_iot;
1993           bus_space_handle_t ioh = sc->sc_regs.ur_ioh;
1994           uint32_t ucr1;
1995           uint32_t mask;
1996 
1997           /* if parameter change is pending, get interrupt when Tx fifo
1998              is completely empty.  otherwise, get interrupt when txfifo
1999              has less characters than threshold */
2000           mask = sc->sc_pending ? IMX_UCR1_TXMPTYEN : IMX_UCR1_TRDYEN;
2001 
2002           ucr1 = sc->sc_ucr1;
2003 
2004           CLR(ucr1, IMX_UCR1_TXMPTYEN|IMX_UCR1_TRDYEN);
2005           if (enable)
2006                     SET(ucr1, mask);
2007 
2008           if (ucr1 != sc->sc_ucr1) {
2009                     bus_space_write_4(iot, ioh, IMX_UCR1, ucr1);
2010                     sc->sc_ucr1 = ucr1;
2011           }
2012 }
2013 
2014 
2015 static void
imxuart_load_params(struct imxuart_softc * sc)2016 imxuart_load_params(struct imxuart_softc *sc)
2017 {
2018           uint32_t ucr2;
2019           bus_space_tag_t iot = sc->sc_regs.ur_iot;
2020           bus_space_handle_t ioh = sc->sc_regs.ur_ioh;
2021 
2022           ucr2 = (sc->sc_ucr2_d & ~IMX_UCR2_ATEN) |
2023               (sc->sc_ucr2 & IMX_UCR2_ATEN);
2024 
2025           bus_space_write_4(iot, ioh, IMX_UCR2, ucr2);
2026           sc->sc_ucr2 = ucr2;
2027 }
2028 
2029 static void
imxuart_load_speed(struct imxuart_softc * sc)2030 imxuart_load_speed(struct imxuart_softc *sc)
2031 {
2032           bus_space_tag_t iot = sc->sc_regs.ur_iot;
2033           bus_space_handle_t ioh = sc->sc_regs.ur_ioh;
2034           int n, rfdiv, ufcr;
2035 
2036 #ifdef notyet
2037           /*
2038            * Set the FIFO threshold based on the receive speed.
2039            *
2040            *  * If it's a low speed, it's probably a mouse or some other
2041            *    interactive device, so set the threshold low.
2042            *  * If it's a high speed, trim the trigger level down to prevent
2043            *    overflows.
2044            *  * Otherwise set it a bit higher.
2045            */
2046           if (t->c_ospeed <= 1200)
2047                     sc->sc_fifo = FIFO_ENABLE | FIFO_TRIGGER_1;
2048           else if (t->c_ospeed <= 38400)
2049                     sc->sc_fifo = FIFO_ENABLE | FIFO_TRIGGER_8;
2050           else
2051                     sc->sc_fifo = FIFO_ENABLE | FIFO_TRIGGER_4;
2052 #endif
2053 
2054           n = 32 - sc->sc_txfifo_thresh;
2055           n = MAX(2, n);
2056 
2057           rfdiv = IMX_UFCR_DIVIDER_TO_RFDIV(imxuart_freqdiv);
2058 
2059           ufcr = (n << IMX_UFCR_TXTL_SHIFT) |
2060                     (rfdiv << IMX_UFCR_RFDIV_SHIFT) |
2061                     (16 << IMX_UFCR_RXTL_SHIFT);
2062 
2063           /* keep DCE/DTE bit */
2064           ufcr |= bus_space_read_4(iot, ioh, IMX_UFCR) & IMX_UFCR_DCEDTE;
2065 
2066           bus_space_write_4(iot, ioh, IMX_UFCR, ufcr);
2067 
2068           /* UBIR must updated before UBMR */
2069           bus_space_write_4(iot, ioh,
2070               IMX_UBIR, sc->sc_ratio.numerator);
2071           bus_space_write_4(iot, ioh,
2072               IMX_UBMR, sc->sc_ratio.modulator);
2073 
2074 
2075 }
2076 
2077 
2078 static void
imxuart_load_pendings(struct imxuart_softc * sc)2079 imxuart_load_pendings(struct imxuart_softc *sc)
2080 {
2081           if (sc->sc_pending & IMXUART_PEND_PARAM)
2082                     imxuart_load_params(sc);
2083           if (sc->sc_pending & IMXUART_PEND_SPEED)
2084                     imxuart_load_speed(sc);
2085           sc->sc_pending = 0;
2086 }
2087 
2088 /*
2089  * The following functions are polled getc and putc routines, shared
2090  * by the console and kgdb glue.
2091  *
2092  * The read-ahead code is so that you can detect pending in-band
2093  * cn_magic in polled mode while doing output rather than having to
2094  * wait until the kernel decides it needs input.
2095  */
2096 
2097 #define   READAHEAD_RING_LEN  16
2098 static int imxuart_readahead[READAHEAD_RING_LEN];
2099 static int imxuart_readahead_in = 0;
2100 static int imxuart_readahead_out = 0;
2101 #define   READAHEAD_IS_EMPTY()          (imxuart_readahead_in==imxuart_readahead_out)
2102 #define   READAHEAD_IS_FULL() \
2103           (((imxuart_readahead_in+1) & (READAHEAD_RING_LEN-1)) ==imxuart_readahead_out)
2104 
2105 int
imxuart_common_getc(dev_t dev,struct imxuart_regs * regsp)2106 imxuart_common_getc(dev_t dev, struct imxuart_regs *regsp)
2107 {
2108           int s = splserial();
2109           u_char c;
2110           bus_space_tag_t iot = regsp->ur_iot;
2111           bus_space_handle_t ioh = regsp->ur_ioh;
2112           uint32_t usr2;
2113 
2114           /* got a character from reading things earlier */
2115           if (!READAHEAD_IS_EMPTY()) {
2116                     c = imxuart_readahead[imxuart_readahead_out];
2117                     imxuart_readahead_out = (imxuart_readahead_out + 1) &
2118                         (READAHEAD_RING_LEN-1);
2119                     splx(s);
2120                     return (c);
2121           }
2122 
2123           /* block until a character becomes available */
2124           while (!((usr2 = bus_space_read_4(iot, ioh, IMX_USR2)) & IMX_USR2_RDR))
2125                     continue;
2126 
2127           c = 0xff & bus_space_read_4(iot, ioh, IMX_URXD);
2128 
2129           {
2130                     int cn_trapped __unused = 0;
2131                     if (!db_active)
2132                               cn_check_magic(dev, c, imxuart_cnm_state);
2133           }
2134           splx(s);
2135           return (c);
2136 }
2137 
2138 void
imxuart_common_putc(dev_t dev,struct imxuart_regs * regsp,int c)2139 imxuart_common_putc(dev_t dev, struct imxuart_regs *regsp, int c)
2140 {
2141           int s = splserial();
2142           int cin, timo;
2143           bus_space_tag_t iot = regsp->ur_iot;
2144           bus_space_handle_t ioh = regsp->ur_ioh;
2145           uint32_t usr2;
2146 
2147           if (!READAHEAD_IS_FULL() &&
2148               ((usr2 = bus_space_read_4(iot, ioh, IMX_USR2)) & IMX_USR2_RDR)) {
2149 
2150                     int __attribute__((__unused__))cn_trapped = 0;
2151                     cin = bus_space_read_4(iot, ioh, IMX_URXD);
2152                     cn_check_magic(dev, cin & 0xff, imxuart_cnm_state);
2153                     imxuart_readahead[imxuart_readahead_in] = cin & 0xff;
2154                     imxuart_readahead_in = (imxuart_readahead_in + 1) &
2155                         (READAHEAD_RING_LEN-1);
2156           }
2157 
2158           /* wait for any pending transmission to finish */
2159           timo = 150000;
2160           do {
2161                     if (bus_space_read_4(iot, ioh, IMX_USR1) & IMX_USR1_TRDY) {
2162                               bus_space_write_4(iot, ioh, IMX_UTXD, c);
2163                               break;
2164                     }
2165           } while(--timo > 0);
2166 
2167           IMXUART_BARRIER(regsp, BR | BW);
2168 
2169           splx(s);
2170 }
2171 
2172 /*
2173  * Initialize UART
2174  */
2175 int
imxuart_init(struct imxuart_regs * regsp,int rate,tcflag_t cflag,int domap)2176 imxuart_init(struct imxuart_regs *regsp, int rate, tcflag_t cflag, int domap)
2177 {
2178           struct imxuart_baudrate_ratio ratio;
2179           int rfdiv = IMX_UFCR_DIVIDER_TO_RFDIV(imxuart_freqdiv);
2180           uint32_t ufcr;
2181           int error;
2182 
2183           if (domap && (error = bus_space_map(regsp->ur_iot, regsp->ur_iobase,
2184                IMX_UART_SIZE, 0, &regsp->ur_ioh)) != 0)
2185                     return error;
2186 
2187           if (imxuart_freq != 0) {
2188                     if (imxuspeed(rate, &ratio) < 0)
2189                               return EINVAL;
2190 
2191                     /* UBIR must updated before UBMR */
2192                     bus_space_write_4(regsp->ur_iot, regsp->ur_ioh,
2193                         IMX_UBIR, ratio.numerator);
2194                     bus_space_write_4(regsp->ur_iot, regsp->ur_ioh,
2195                         IMX_UBMR, ratio.modulator);
2196           }
2197 
2198           /* XXX: DTREN, DPEC */
2199           bus_space_write_4(regsp->ur_iot, regsp->ur_ioh, IMX_UCR3,
2200               IMX_UCR3_DSR|IMX_UCR3_RXDMUXSEL);
2201 
2202           ufcr = bus_space_read_4(regsp->ur_iot, regsp->ur_ioh, IMX_UFCR);
2203           ufcr &= ~IMX_UFCR_TXTL;
2204           ufcr |= (8 << IMX_UFCR_TXTL_SHIFT);
2205           ufcr &= ~IMX_UFCR_RXTL;
2206           ufcr |= (1 << IMX_UFCR_RXTL_SHIFT);
2207           if (imxuart_freq != 0) {
2208                     ufcr &= ~IMX_UFCR_RFDIV;
2209                     ufcr |= (rfdiv << IMX_UFCR_RFDIV_SHIFT);
2210           }
2211           bus_space_write_4(regsp->ur_iot, regsp->ur_ioh, IMX_UFCR, ufcr);
2212 
2213           if (imxuart_freq != 0) {
2214                     bus_space_write_4(regsp->ur_iot, regsp->ur_ioh, IMX_ONEMS,
2215                         imxuart_freq / imxuart_freqdiv / 1000);
2216           }
2217 
2218           bus_space_write_4(regsp->ur_iot, regsp->ur_ioh, IMX_UCR2,
2219                                 IMX_UCR2_IRTS|
2220                                 IMX_UCR2_CTSC|
2221                                 IMX_UCR2_WS|IMX_UCR2_TXEN|
2222                                 IMX_UCR2_RXEN|IMX_UCR2_SRST);
2223           /* clear status registers */
2224           bus_space_write_4(regsp->ur_iot, regsp->ur_ioh, IMX_USR1, 0xffff);
2225           bus_space_write_4(regsp->ur_iot, regsp->ur_ioh, IMX_USR2, 0xffff);
2226 
2227 
2228           bus_space_write_4(regsp->ur_iot, regsp->ur_ioh, IMX_UCR1,
2229               IMX_UCR1_UARTEN);
2230 
2231           return (0);
2232 }
2233 
2234 
2235 /*
2236  * Following are all routines needed for UART to act as console
2237  */
2238 struct consdev imxucons = {
2239           NULL, NULL, imxucngetc, imxucnputc, imxucnpollc, NULL, NULL, NULL,
2240           NODEV, CN_NORMAL
2241 };
2242 
2243 
2244 int
imxuart_cnattach(bus_space_tag_t iot,paddr_t iobase,u_int rate,tcflag_t cflag)2245 imxuart_cnattach(bus_space_tag_t iot, paddr_t iobase, u_int rate,
2246     tcflag_t cflag)
2247 {
2248           struct imxuart_regs regs;
2249           int res;
2250 
2251           regs.ur_iot = iot;
2252           regs.ur_iobase = iobase;
2253 
2254           res = imxuart_init(&regs, rate, cflag, true);
2255           if (res)
2256                     return (res);
2257 
2258           cn_tab = &imxucons;
2259           cn_init_magic(&imxuart_cnm_state);
2260           cn_set_magic("\047\001"); /* default magic is BREAK */
2261 
2262           imxuconsrate = rate;
2263           imxuconscflag = cflag;
2264 
2265           imxuconsregs = regs;
2266 
2267           return 0;
2268 }
2269 
2270 int
imxucngetc(dev_t dev)2271 imxucngetc(dev_t dev)
2272 {
2273           return (imxuart_common_getc(dev, &imxuconsregs));
2274 }
2275 
2276 /*
2277  * Console kernel output character routine.
2278  */
2279 void
imxucnputc(dev_t dev,int c)2280 imxucnputc(dev_t dev, int c)
2281 {
2282           imxuart_common_putc(dev, &imxuconsregs, c);
2283 }
2284 
2285 void
imxucnpollc(dev_t dev,int on)2286 imxucnpollc(dev_t dev, int on)
2287 {
2288 
2289           imxuart_readahead_in = 0;
2290           imxuart_readahead_out = 0;
2291 }
2292 
2293 #ifdef KGDB
2294 int
imxuart_kgdb_attach(bus_space_tag_t iot,paddr_t iobase,u_int rate,tcflag_t cflag)2295 imxuart_kgdb_attach(bus_space_tag_t iot, paddr_t iobase, u_int rate,
2296     tcflag_t cflag)
2297 {
2298           int res;
2299 
2300           if (iot == imxuconsregs.ur_iot &&
2301               iobase == imxuconsregs.ur_iobase) {
2302 #if !defined(DDB)
2303                     return (EBUSY); /* cannot share with console */
2304 #else
2305                     imxu_kgdb_regs.ur_iot = iot;
2306                     imxu_kgdb_regs.ur_ioh = imxuconsregs.ur_ioh;
2307                     imxu_kgdb_regs.ur_iobase = iobase;
2308 #endif
2309           } else {
2310                     imxu_kgdb_regs.ur_iot = iot;
2311                     imxu_kgdb_regs.ur_iobase = iobase;
2312 
2313                     res = imxuart_init(&imxu_kgdb_regs, rate, cflag, true);
2314                     if (res)
2315                               return (res);
2316 
2317                     /*
2318                      * XXXfvdl this shouldn't be needed, but the cn_magic goo
2319                      * expects this to be initialized
2320                      */
2321                     cn_init_magic(&imxuart_cnm_state);
2322                     cn_set_magic("\047\001");
2323           }
2324 
2325           kgdb_attach(imxuart_kgdb_getc, imxuart_kgdb_putc, &imxu_kgdb_regs);
2326           kgdb_dev = 123; /* unneeded, only to satisfy some tests */
2327 
2328           return (0);
2329 }
2330 
2331 /* ARGSUSED */
2332 int
imxuart_kgdb_getc(void * arg)2333 imxuart_kgdb_getc(void *arg)
2334 {
2335           struct imxuart_regs *regs = arg;
2336 
2337           return (imxuart_common_getc(NODEV, regs));
2338 }
2339 
2340 /* ARGSUSED */
2341 void
imxuart_kgdb_putc(void * arg,int c)2342 imxuart_kgdb_putc(void *arg, int c)
2343 {
2344           struct imxuart_regs *regs = arg;
2345 
2346           imxuart_common_putc(NODEV, regs, c);
2347 }
2348 #endif /* KGDB */
2349 
2350 /* helper function to identify the imxu ports used by
2351  console or KGDB (and not yet autoconf attached) */
2352 int
imxuart_is_console(bus_space_tag_t iot,bus_addr_t iobase,bus_space_handle_t * ioh)2353 imxuart_is_console(bus_space_tag_t iot, bus_addr_t iobase, bus_space_handle_t *ioh)
2354 {
2355           bus_space_handle_t help;
2356 
2357           if (!imxuconsattached &&
2358               iot == imxuconsregs.ur_iot && iobase == imxuconsregs.ur_iobase)
2359                     help = imxuconsregs.ur_ioh;
2360 #ifdef KGDB
2361           else if (!imxu_kgdb_attached &&
2362               iot == imxu_kgdb_regs.ur_iot && iobase == imxu_kgdb_regs.ur_iobase)
2363                     help = imxu_kgdb_regs.ur_ioh;
2364 #endif
2365           else
2366                     return (0);
2367 
2368           if (ioh)
2369                     *ioh = help;
2370           return (1);
2371 }
2372 
2373 #ifdef notyet
2374 
2375 bool
imxuart_cleanup(device_t self,int how)2376 imxuart_cleanup(device_t self, int how)
2377 {
2378 /*
2379  * this routine exists to serve as a shutdown hook for systems that
2380  * have firmware which doesn't interact properly with a imxuart device in
2381  * FIFO mode.
2382  */
2383           struct imxuart_softc *sc = device_private(self);
2384 
2385           if (ISSET(sc->sc_hwflags, IMXUART_HW_FIFO))
2386                     UR_WRITE_1(&sc->sc_regs, IMXUART_REG_FIFO, 0);
2387 
2388           return true;
2389 }
2390 #endif
2391 
2392 #ifdef notyet
2393 bool
imxuart_suspend(device_t self PMF_FN_ARGS)2394 imxuart_suspend(device_t self PMF_FN_ARGS)
2395 {
2396           struct imxuart_softc *sc = device_private(self);
2397 
2398           UR_WRITE_1(&sc->sc_regs, IMXUART_REG_IER, 0);
2399           (void)CSR_READ_1(&sc->sc_regs, IMXUART_REG_IIR);
2400 
2401           return true;
2402 }
2403 #endif
2404 
2405 #ifdef notyet
2406 bool
imxuart_resume(device_t self PMF_FN_ARGS)2407 imxuart_resume(device_t self PMF_FN_ARGS)
2408 {
2409           struct imxuart_softc *sc = device_private(self);
2410 
2411           mutex_spin_enter(&sc->sc_lock);
2412           imxuart_loadchannelregs(sc);
2413           mutex_spin_exit(&sc->sc_lock);
2414 
2415           return true;
2416 }
2417 #endif
2418 
2419 static void
imxuart_enable_debugport(struct imxuart_softc * sc)2420 imxuart_enable_debugport(struct imxuart_softc *sc)
2421 {
2422           bus_space_tag_t iot = sc->sc_regs.ur_iot;
2423           bus_space_handle_t ioh = sc->sc_regs.ur_ioh;
2424 
2425           if (sc->sc_hwflags & (IMXUART_HW_CONSOLE|IMXUART_HW_KGDB)) {
2426 
2427                     /* Turn on line break interrupt, set carrier. */
2428 
2429                     sc->sc_ucr3 |= IMX_UCR3_DSR;
2430                     bus_space_write_4(iot, ioh, IMX_UCR3, sc->sc_ucr3);
2431 
2432                     sc->sc_ucr4 |= IMX_UCR4_BKEN;
2433                     bus_space_write_4(iot, ioh, IMX_UCR4, sc->sc_ucr4);
2434 
2435                     sc->sc_ucr2 |= IMX_UCR2_TXEN|IMX_UCR2_RXEN|
2436                         IMX_UCR2_CTS;
2437                     bus_space_write_4(iot, ioh, IMX_UCR2, sc->sc_ucr2);
2438 
2439                     sc->sc_ucr1 |= IMX_UCR1_UARTEN;
2440                     bus_space_write_4(iot, ioh, IMX_UCR1, sc->sc_ucr1);
2441           }
2442 }
2443 
2444 
2445 void
imxuart_set_frequency(u_int freq,u_int div)2446 imxuart_set_frequency(u_int freq, u_int div)
2447 {
2448           imxuart_freq = freq;
2449           imxuart_freqdiv = div;
2450 }
2451