1 /*-
2  * Copyright (c) 2003 Marcel Moolenaar
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  *
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/bus.h>
33 #include <sys/conf.h>
34 #include <machine/bus.h>
35 
36 #include <dev/uart/uart.h>
37 #include <dev/uart/uart_cpu.h>
38 #include <dev/uart/uart_bus.h>
39 
40 #include <dev/ic/sab82532.h>
41 
42 #include "uart_if.h"
43 
44 #define	DEFAULT_RCLK	29491200
45 
46 /*
47  * NOTE: To allow us to read the baudrate divisor from the chip, we
48  * copy the value written to the write-only BGR register to an unused
49  * read-write register. We use TCR for that.
50  */
51 
52 static int
53 sab82532_delay(struct uart_bas *bas)
54 {
55 	int divisor, m, n;
56 	uint8_t bgr, ccr2;
57 
58 	bgr = uart_getreg(bas, SAB_TCR);
59 	ccr2 = uart_getreg(bas, SAB_CCR2);
60 	n = (bgr & 0x3f) + 1;
61 	m = (bgr >> 6) | ((ccr2 >> 4) & 0xC);
62 	divisor = n * (1<<m);
63 
64 	/* 1/10th the time to transmit 1 character (estimate). */
65 	return (16000000 * divisor / bas->rclk);
66 }
67 
68 static int
69 sab82532_divisor(int rclk, int baudrate)
70 {
71 	int act_baud, act_div, divisor;
72 	int error, m, n;
73 
74 	if (baudrate == 0)
75 		return (0);
76 
77 	divisor = (rclk / (baudrate << 3) + 1) >> 1;
78 	if (divisor < 2 || divisor >= 1048576)
79 		return (0);
80 
81 	/* Find the best (N+1,M) pair. */
82 	for (m = 1; m < 15; m++) {
83 		n = divisor / (1<<m);
84 		if (n < 1 || n > 63)
85 			continue;
86 		act_div = n * (1<<m);
87 		act_baud = rclk / (act_div << 4);
88 
89 		/* 10 times error in percent: */
90 		error = ((act_baud - baudrate) * 2000 / baudrate + 1) >> 1;
91 
92 		/* 3.0% maximum error tolerance: */
93 		if (error < -30 || error > 30)
94 			continue;
95 
96 		/* Got it. */
97 		return ((n - 1) | (m << 6));
98 	}
99 
100 	return (0);
101 }
102 
103 static void
104 sab82532_flush(struct uart_bas *bas, int what)
105 {
106 
107 	if (what & UART_FLUSH_TRANSMITTER) {
108 		while (uart_getreg(bas, SAB_STAR) & SAB_STAR_CEC)
109 			;
110 		uart_setreg(bas, SAB_CMDR, SAB_CMDR_XRES);
111 		uart_barrier(bas);
112 	}
113 	if (what & UART_FLUSH_RECEIVER) {
114 		while (uart_getreg(bas, SAB_STAR) & SAB_STAR_CEC)
115 			;
116 		uart_setreg(bas, SAB_CMDR, SAB_CMDR_RRES);
117 		uart_barrier(bas);
118 	}
119 }
120 
121 static int
122 sab82532_param(struct uart_bas *bas, int baudrate, int databits, int stopbits,
123     int parity)
124 {
125 	int divisor;
126 	uint8_t ccr2, dafo;
127 
128 	if (databits >= 8)
129 		dafo = SAB_DAFO_CHL_CS8;
130 	else if (databits == 7)
131 		dafo = SAB_DAFO_CHL_CS7;
132 	else if (databits == 6)
133 		dafo = SAB_DAFO_CHL_CS6;
134 	else
135 		dafo = SAB_DAFO_CHL_CS5;
136 	if (stopbits > 1)
137 		dafo |= SAB_DAFO_STOP;
138 	switch (parity) {
139 	case UART_PARITY_EVEN:	dafo |= SAB_DAFO_PAR_EVEN; break;
140 	case UART_PARITY_MARK:	dafo |= SAB_DAFO_PAR_MARK; break;
141 	case UART_PARITY_NONE:	dafo |= SAB_DAFO_PAR_NONE; break;
142 	case UART_PARITY_ODD:	dafo |= SAB_DAFO_PAR_ODD; break;
143 	case UART_PARITY_SPACE:	dafo |= SAB_DAFO_PAR_SPACE; break;
144 	default:		return (EINVAL);
145 	}
146 
147 	/* Set baudrate. */
148 	if (baudrate > 0) {
149 		divisor = sab82532_divisor(bas->rclk, baudrate);
150 		if (divisor == 0)
151 			return (EINVAL);
152 		uart_setreg(bas, SAB_BGR, divisor & 0xff);
153 		uart_barrier(bas);
154 		/* Allow reading the (n-1,m) tuple from the chip. */
155 		uart_setreg(bas, SAB_TCR, divisor & 0xff);
156 		uart_barrier(bas);
157 		ccr2 = uart_getreg(bas, SAB_CCR2);
158 		ccr2 &= ~(SAB_CCR2_BR9 | SAB_CCR2_BR8);
159 		ccr2 |= (divisor >> 2) & (SAB_CCR2_BR9 | SAB_CCR2_BR8);
160 		uart_setreg(bas, SAB_CCR2, ccr2);
161 		uart_barrier(bas);
162 	}
163 
164 	uart_setreg(bas, SAB_DAFO, dafo);
165 	uart_barrier(bas);
166 	return (0);
167 }
168 
169 /*
170  * Low-level UART interface.
171  */
172 static int sab82532_probe(struct uart_bas *bas);
173 static void sab82532_init(struct uart_bas *bas, int, int, int, int);
174 static void sab82532_term(struct uart_bas *bas);
175 static void sab82532_putc(struct uart_bas *bas, int);
176 static int sab82532_poll(struct uart_bas *bas);
177 static int sab82532_getc(struct uart_bas *bas);
178 
179 struct uart_ops uart_sab82532_ops = {
180 	.probe = sab82532_probe,
181 	.init = sab82532_init,
182 	.term = sab82532_term,
183 	.putc = sab82532_putc,
184 	.poll = sab82532_poll,
185 	.getc = sab82532_getc,
186 };
187 
188 static int
189 sab82532_probe(struct uart_bas *bas)
190 {
191 
192 	return (0);
193 }
194 
195 static void
196 sab82532_init(struct uart_bas *bas, int baudrate, int databits, int stopbits,
197     int parity)
198 {
199 	uint8_t ccr0, pvr;
200 
201 	if (bas->rclk == 0)
202 		bas->rclk = DEFAULT_RCLK;
203 
204 	/*
205 	 * Set all pins, except the DTR pins (pin 1 and 2) to be inputs.
206 	 * Pin 4 is magical, meaning that I don't know what it does, but
207 	 * it too has to be set to output.
208 	 */
209 	uart_setreg(bas, SAB_PCR,
210 	    ~(SAB_PVR_DTR_A|SAB_PVR_DTR_B|SAB_PVR_MAGIC));
211 	uart_barrier(bas);
212 	/* Disable port interrupts. */
213 	uart_setreg(bas, SAB_PIM, 0xff);
214 	uart_barrier(bas);
215 	/* Interrupts are active low. */
216 	uart_setreg(bas, SAB_IPC, SAB_IPC_ICPL);
217 	uart_barrier(bas);
218 	/* Set DTR. */
219 	pvr = uart_getreg(bas, SAB_PVR);
220 	switch (bas->chan) {
221 	case 1:
222 		pvr &= ~SAB_PVR_DTR_A;
223 		break;
224 	case 2:
225 		pvr &= ~SAB_PVR_DTR_B;
226 		break;
227 	}
228 	uart_setreg(bas, SAB_PVR, pvr | SAB_PVR_MAGIC);
229 	uart_barrier(bas);
230 
231 	/* power down */
232 	uart_setreg(bas, SAB_CCR0, 0);
233 	uart_barrier(bas);
234 
235 	/* set basic configuration */
236 	ccr0 = SAB_CCR0_MCE|SAB_CCR0_SC_NRZ|SAB_CCR0_SM_ASYNC;
237 	uart_setreg(bas, SAB_CCR0, ccr0);
238 	uart_barrier(bas);
239 	uart_setreg(bas, SAB_CCR1, SAB_CCR1_ODS|SAB_CCR1_BCR|SAB_CCR1_CM_7);
240 	uart_barrier(bas);
241 	uart_setreg(bas, SAB_CCR2, SAB_CCR2_BDF|SAB_CCR2_SSEL|SAB_CCR2_TOE);
242 	uart_barrier(bas);
243 	uart_setreg(bas, SAB_CCR3, 0);
244 	uart_barrier(bas);
245 	uart_setreg(bas, SAB_CCR4, SAB_CCR4_MCK4|SAB_CCR4_EBRG|SAB_CCR4_ICD);
246 	uart_barrier(bas);
247 	uart_setreg(bas, SAB_MODE, SAB_MODE_FCTS|SAB_MODE_RTS|SAB_MODE_RAC);
248 	uart_barrier(bas);
249 	uart_setreg(bas, SAB_RFC, SAB_RFC_DPS|SAB_RFC_RFDF|
250 	    SAB_RFC_RFTH_32CHAR);
251 	uart_barrier(bas);
252 
253 	sab82532_param(bas, baudrate, databits, stopbits, parity);
254 
255 	/* Clear interrupts. */
256 	uart_setreg(bas, SAB_IMR0, (unsigned char)~SAB_IMR0_TCD);
257 	uart_setreg(bas, SAB_IMR1, 0xff);
258 	uart_barrier(bas);
259 	uart_getreg(bas, SAB_ISR0);
260 	uart_getreg(bas, SAB_ISR1);
261 	uart_barrier(bas);
262 
263 	sab82532_flush(bas, UART_FLUSH_TRANSMITTER|UART_FLUSH_RECEIVER);
264 
265 	/* Power up. */
266 	uart_setreg(bas, SAB_CCR0, ccr0|SAB_CCR0_PU);
267 	uart_barrier(bas);
268 }
269 
270 static void
271 sab82532_term(struct uart_bas *bas)
272 {
273 	uint8_t pvr;
274 
275 	pvr = uart_getreg(bas, SAB_PVR);
276 	switch (bas->chan) {
277 	case 1:
278 		pvr |= SAB_PVR_DTR_A;
279 		break;
280 	case 2:
281 		pvr |= SAB_PVR_DTR_B;
282 		break;
283 	}
284 	uart_setreg(bas, SAB_PVR, pvr);
285 	uart_barrier(bas);
286 }
287 
288 static void
289 sab82532_putc(struct uart_bas *bas, int c)
290 {
291 	int delay, limit;
292 
293 	/* 1/10th the time to transmit 1 character (estimate). */
294 	delay = sab82532_delay(bas);
295 
296 	limit = 20;
297 	while ((uart_getreg(bas, SAB_STAR) & SAB_STAR_TEC) && --limit)
298 		DELAY(delay);
299 	uart_setreg(bas, SAB_TIC, c);
300 	limit = 20;
301 	while ((uart_getreg(bas, SAB_STAR) & SAB_STAR_TEC) && --limit)
302 		DELAY(delay);
303 }
304 
305 static int
306 sab82532_poll(struct uart_bas *bas)
307 {
308 
309 	if (uart_getreg(bas, SAB_STAR) & SAB_STAR_RFNE)
310 		return (sab82532_getc(bas));
311 	return (-1);
312 }
313 
314 static int
315 sab82532_getc(struct uart_bas *bas)
316 {
317 	int c, delay;
318 
319 	/* 1/10th the time to transmit 1 character (estimate). */
320 	delay = sab82532_delay(bas);
321 
322 	while (!(uart_getreg(bas, SAB_STAR) & SAB_STAR_RFNE))
323 		DELAY(delay);
324 
325 	while (uart_getreg(bas, SAB_STAR) & SAB_STAR_CEC)
326 		;
327 	uart_setreg(bas, SAB_CMDR, SAB_CMDR_RFRD);
328 	uart_barrier(bas);
329 
330 	while (!(uart_getreg(bas, SAB_ISR0) & SAB_ISR0_TCD))
331 		DELAY(delay);
332 
333 	c = uart_getreg(bas, SAB_RFIFO);
334 	uart_barrier(bas);
335 
336 	/* Blow away everything left in the FIFO... */
337 	while (uart_getreg(bas, SAB_STAR) & SAB_STAR_CEC)
338 		;
339 	uart_setreg(bas, SAB_CMDR, SAB_CMDR_RMC);
340 	uart_barrier(bas);
341 	return (c);
342 }
343 
344 /*
345  * High-level UART interface.
346  */
347 struct sab82532_softc {
348 	struct uart_softc base;
349 };
350 
351 static int sab82532_bus_attach(struct uart_softc *);
352 static int sab82532_bus_detach(struct uart_softc *);
353 static int sab82532_bus_flush(struct uart_softc *, int);
354 static int sab82532_bus_getsig(struct uart_softc *);
355 static int sab82532_bus_ioctl(struct uart_softc *, int, intptr_t);
356 static int sab82532_bus_ipend(struct uart_softc *);
357 static int sab82532_bus_param(struct uart_softc *, int, int, int, int);
358 static int sab82532_bus_probe(struct uart_softc *);
359 static int sab82532_bus_receive(struct uart_softc *);
360 static int sab82532_bus_setsig(struct uart_softc *, int);
361 static int sab82532_bus_transmit(struct uart_softc *);
362 
363 static kobj_method_t sab82532_methods[] = {
364 	KOBJMETHOD(uart_attach,		sab82532_bus_attach),
365 	KOBJMETHOD(uart_detach,		sab82532_bus_detach),
366 	KOBJMETHOD(uart_flush,		sab82532_bus_flush),
367 	KOBJMETHOD(uart_getsig,		sab82532_bus_getsig),
368 	KOBJMETHOD(uart_ioctl,		sab82532_bus_ioctl),
369 	KOBJMETHOD(uart_ipend,		sab82532_bus_ipend),
370 	KOBJMETHOD(uart_param,		sab82532_bus_param),
371 	KOBJMETHOD(uart_probe,		sab82532_bus_probe),
372 	KOBJMETHOD(uart_receive,	sab82532_bus_receive),
373 	KOBJMETHOD(uart_setsig,		sab82532_bus_setsig),
374 	KOBJMETHOD(uart_transmit,	sab82532_bus_transmit),
375 	{ 0, 0 }
376 };
377 
378 struct uart_class uart_sab82532_class = {
379 	"sab82532 class",
380 	sab82532_methods,
381 	sizeof(struct sab82532_softc),
382 	.uc_range = 64,
383 	.uc_rclk = DEFAULT_RCLK
384 };
385 
386 #define	SIGCHG(c, i, s, d)				\
387 	if (c) {					\
388 		i |= (i & s) ? s : s | d;		\
389 	} else {					\
390 		i = (i & s) ? (i & ~s) | d : i;		\
391 	}
392 
393 static int
394 sab82532_bus_attach(struct uart_softc *sc)
395 {
396 	struct uart_bas *bas;
397 	uint8_t imr0, imr1;
398 
399 	bas = &sc->sc_bas;
400 	if (sc->sc_sysdev == NULL)
401 		sab82532_init(bas, 9600, 8, 1, UART_PARITY_NONE);
402 
403 	sc->sc_rxfifosz = 32;
404 	sc->sc_txfifosz = 32;
405 
406 	imr0 = SAB_IMR0_TCD|SAB_IMR0_TIME|SAB_IMR0_CDSC|SAB_IMR0_RFO|
407 	    SAB_IMR0_RPF;
408 	uart_setreg(bas, SAB_IMR0, 0xff & ~imr0);
409 	imr1 = SAB_IMR1_BRKT|SAB_IMR1_ALLS|SAB_IMR1_CSC;
410 	uart_setreg(bas, SAB_IMR1, 0xff & ~imr1);
411 	uart_barrier(bas);
412 
413 	if (sc->sc_sysdev == NULL)
414 		sab82532_bus_setsig(sc, SER_DDTR|SER_DRTS);
415 	(void)sab82532_bus_getsig(sc);
416 	return (0);
417 }
418 
419 static int
420 sab82532_bus_detach(struct uart_softc *sc)
421 {
422 	struct uart_bas *bas;
423 
424 	bas = &sc->sc_bas;
425 	uart_setreg(bas, SAB_IMR0, 0xff);
426 	uart_setreg(bas, SAB_IMR1, 0xff);
427 	uart_barrier(bas);
428 	uart_getreg(bas, SAB_ISR0);
429 	uart_getreg(bas, SAB_ISR1);
430 	uart_barrier(bas);
431 	uart_setreg(bas, SAB_CCR0, 0);
432 	uart_barrier(bas);
433 	return (0);
434 }
435 
436 static int
437 sab82532_bus_flush(struct uart_softc *sc, int what)
438 {
439 
440 	mtx_lock_spin(&sc->sc_hwmtx);
441 	sab82532_flush(&sc->sc_bas, what);
442 	mtx_unlock_spin(&sc->sc_hwmtx);
443 	return (0);
444 }
445 
446 static int
447 sab82532_bus_getsig(struct uart_softc *sc)
448 {
449 	struct uart_bas *bas;
450 	uint32_t new, old, sig;
451 	uint8_t pvr, star, vstr;
452 
453 	bas = &sc->sc_bas;
454 	do {
455 		old = sc->sc_hwsig;
456 		sig = old;
457 		mtx_lock_spin(&sc->sc_hwmtx);
458 		star = uart_getreg(bas, SAB_STAR);
459 		SIGCHG(star & SAB_STAR_CTS, sig, SER_CTS, SER_DCTS);
460 		vstr = uart_getreg(bas, SAB_VSTR);
461 		SIGCHG(vstr & SAB_VSTR_CD, sig, SER_DCD, SER_DDCD);
462 		pvr = ~uart_getreg(bas, SAB_PVR);
463 		switch (bas->chan) {
464 		case 1:
465 			pvr &= SAB_PVR_DSR_A;
466 			break;
467 		case 2:
468 			pvr &= SAB_PVR_DSR_B;
469 			break;
470 		}
471 		SIGCHG(pvr, sig, SER_DSR, SER_DDSR);
472 		mtx_unlock_spin(&sc->sc_hwmtx);
473 		new = sig & ~UART_SIGMASK_DELTA;
474 	} while (!atomic_cmpset_32(&sc->sc_hwsig, old, new));
475 	return (sig);
476 }
477 
478 static int
479 sab82532_bus_ioctl(struct uart_softc *sc, int request, intptr_t data)
480 {
481 	struct uart_bas *bas;
482 	uint8_t dafo, mode;
483 	int error;
484 
485 	bas = &sc->sc_bas;
486 	error = 0;
487 	mtx_lock_spin(&sc->sc_hwmtx);
488 	switch (request) {
489 	case UART_IOCTL_BREAK:
490 		dafo = uart_getreg(bas, SAB_DAFO);
491 		if (data)
492 			dafo |= SAB_DAFO_XBRK;
493 		else
494 			dafo &= ~SAB_DAFO_XBRK;
495 		uart_setreg(bas, SAB_DAFO, dafo);
496 		uart_barrier(bas);
497 		break;
498 	case UART_IOCTL_IFLOW:
499 		mode = uart_getreg(bas, SAB_MODE);
500 		if (data) {
501 			mode &= ~SAB_MODE_RTS;
502 			mode |= SAB_MODE_FRTS;
503 		} else {
504 			mode |= SAB_MODE_RTS;
505 			mode &= ~SAB_MODE_FRTS;
506 		}
507 		uart_setreg(bas, SAB_MODE, mode);
508 		uart_barrier(bas);
509 		break;
510 	case UART_IOCTL_OFLOW:
511 		mode = uart_getreg(bas, SAB_MODE);
512 		if (data)
513 			mode &= ~SAB_MODE_FCTS;
514 		else
515 			mode |= SAB_MODE_FCTS;
516 		uart_setreg(bas, SAB_MODE, mode);
517 		uart_barrier(bas);
518 		break;
519 	default:
520 		error = EINVAL;
521 		break;
522 	}
523 	mtx_unlock_spin(&sc->sc_hwmtx);
524 	return (error);
525 }
526 
527 static int
528 sab82532_bus_ipend(struct uart_softc *sc)
529 {
530 	struct uart_bas *bas;
531 	int ipend;
532 	uint8_t isr0, isr1;
533 
534 	bas = &sc->sc_bas;
535 	mtx_lock_spin(&sc->sc_hwmtx);
536 	isr0 = uart_getreg(bas, SAB_ISR0);
537 	isr1 = uart_getreg(bas, SAB_ISR1);
538 	uart_barrier(bas);
539 	if (isr0 & SAB_ISR0_TIME) {
540 		while (uart_getreg(bas, SAB_STAR) & SAB_STAR_CEC)
541 			;
542 		uart_setreg(bas, SAB_CMDR, SAB_CMDR_RFRD);
543 		uart_barrier(bas);
544 	}
545 	mtx_unlock_spin(&sc->sc_hwmtx);
546 
547 	ipend = 0;
548 	if (isr1 & SAB_ISR1_BRKT)
549 		ipend |= UART_IPEND_BREAK;
550 	if (isr0 & SAB_ISR0_RFO)
551 		ipend |= UART_IPEND_OVERRUN;
552 	if (isr0 & (SAB_ISR0_TCD|SAB_ISR0_RPF))
553 		ipend |= UART_IPEND_RXREADY;
554 	if ((isr0 & SAB_ISR0_CDSC) || (isr1 & SAB_ISR1_CSC))
555 		ipend |= UART_IPEND_SIGCHG;
556 	if (isr1 & SAB_ISR1_ALLS)
557 		ipend |= UART_IPEND_TXIDLE;
558 
559 	return (ipend);
560 }
561 
562 static int
563 sab82532_bus_param(struct uart_softc *sc, int baudrate, int databits,
564     int stopbits, int parity)
565 {
566 	struct uart_bas *bas;
567 	int error;
568 
569 	bas = &sc->sc_bas;
570 	mtx_lock_spin(&sc->sc_hwmtx);
571 	error = sab82532_param(bas, baudrate, databits, stopbits, parity);
572 	mtx_unlock_spin(&sc->sc_hwmtx);
573 	return (error);
574 }
575 
576 static int
577 sab82532_bus_probe(struct uart_softc *sc)
578 {
579 	char buf[80];
580 	const char *vstr;
581 	int error;
582 	char ch;
583 
584 	error = sab82532_probe(&sc->sc_bas);
585 	if (error)
586 		return (error);
587 
588 	ch = sc->sc_bas.chan - 1 + 'A';
589 
590 	switch (uart_getreg(&sc->sc_bas, SAB_VSTR) & SAB_VSTR_VMASK) {
591 	case SAB_VSTR_V_1:
592 		vstr = "v1";
593 		break;
594 	case SAB_VSTR_V_2:
595 		vstr = "v2";
596 		break;
597 	case SAB_VSTR_V_32:
598 		vstr = "v3.2";
599 		sc->sc_hwiflow = 0;	/* CTS doesn't work with RFC:RFDF. */
600 		sc->sc_hwoflow = 1;
601 		break;
602 	default:
603 		vstr = "v4?";
604 		break;
605 	}
606 
607 	snprintf(buf, sizeof(buf), "SAB 82532 %s, channel %c", vstr, ch);
608 	device_set_desc_copy(sc->sc_dev, buf);
609 	return (0);
610 }
611 
612 static int
613 sab82532_bus_receive(struct uart_softc *sc)
614 {
615 	struct uart_bas *bas;
616 	int i, rbcl, xc;
617 	uint8_t s;
618 
619 	bas = &sc->sc_bas;
620 	mtx_lock_spin(&sc->sc_hwmtx);
621 	if (uart_getreg(bas, SAB_STAR) & SAB_STAR_RFNE) {
622 		rbcl = uart_getreg(bas, SAB_RBCL) & 31;
623 		if (rbcl == 0)
624 			rbcl = 32;
625 		for (i = 0; i < rbcl; i += 2) {
626 			if (uart_rx_full(sc)) {
627 				sc->sc_rxbuf[sc->sc_rxput] = UART_STAT_OVERRUN;
628 				break;
629 			}
630 			xc = uart_getreg(bas, SAB_RFIFO);
631 			s = uart_getreg(bas, SAB_RFIFO + 1);
632 			if (s & SAB_RSTAT_FE)
633 				xc |= UART_STAT_FRAMERR;
634 			if (s & SAB_RSTAT_PE)
635 				xc |= UART_STAT_PARERR;
636 			uart_rx_put(sc, xc);
637 		}
638 	}
639 
640 	while (uart_getreg(bas, SAB_STAR) & SAB_STAR_CEC)
641 		;
642 	uart_setreg(bas, SAB_CMDR, SAB_CMDR_RMC);
643 	uart_barrier(bas);
644 	mtx_unlock_spin(&sc->sc_hwmtx);
645 	return (0);
646 }
647 
648 static int
649 sab82532_bus_setsig(struct uart_softc *sc, int sig)
650 {
651 	struct uart_bas *bas;
652 	uint32_t new, old;
653 	uint8_t mode, pvr;
654 
655 	bas = &sc->sc_bas;
656 	do {
657 		old = sc->sc_hwsig;
658 		new = old;
659 		if (sig & SER_DDTR) {
660 			SIGCHG(sig & SER_DTR, new, SER_DTR,
661 			    SER_DDTR);
662 		}
663 		if (sig & SER_DRTS) {
664 			SIGCHG(sig & SER_RTS, new, SER_RTS,
665 			    SER_DRTS);
666 		}
667 	} while (!atomic_cmpset_32(&sc->sc_hwsig, old, new));
668 
669 	mtx_lock_spin(&sc->sc_hwmtx);
670 	/* Set DTR pin. */
671 	pvr = uart_getreg(bas, SAB_PVR);
672 	switch (bas->chan) {
673 	case 1:
674 		if (new & SER_DTR)
675 			pvr &= ~SAB_PVR_DTR_A;
676 		else
677 			pvr |= SAB_PVR_DTR_A;
678 		break;
679 	case 2:
680 		if (new & SER_DTR)
681 			pvr &= ~SAB_PVR_DTR_B;
682 		else
683 			pvr |= SAB_PVR_DTR_B;
684 		break;
685 	}
686 	uart_setreg(bas, SAB_PVR, pvr);
687 
688 	/* Set RTS pin. */
689 	mode = uart_getreg(bas, SAB_MODE);
690 	if (new & SER_RTS)
691 		mode &= ~SAB_MODE_FRTS;
692 	else
693 		mode |= SAB_MODE_FRTS;
694 	uart_setreg(bas, SAB_MODE, mode);
695 	uart_barrier(bas);
696 	mtx_unlock_spin(&sc->sc_hwmtx);
697 	return (0);
698 }
699 
700 static int
701 sab82532_bus_transmit(struct uart_softc *sc)
702 {
703 	struct uart_bas *bas;
704 	int i;
705 
706 	bas = &sc->sc_bas;
707 	mtx_lock_spin(&sc->sc_hwmtx);
708 	while (!(uart_getreg(bas, SAB_STAR) & SAB_STAR_XFW))
709 		;
710 	for (i = 0; i < sc->sc_txdatasz; i++)
711 		uart_setreg(bas, SAB_XFIFO + i, sc->sc_txbuf[i]);
712 	uart_barrier(bas);
713 	while (uart_getreg(bas, SAB_STAR) & SAB_STAR_CEC)
714 		;
715 	uart_setreg(bas, SAB_CMDR, SAB_CMDR_XF);
716 	sc->sc_txbusy = 1;
717 	mtx_unlock_spin(&sc->sc_hwmtx);
718 	return (0);
719 }
720