xref: /freebsd/sys/dev/uart/uart_dev_z8530.c (revision 511cecafd6f81e86fe43552c72dae3f6e584e71d)
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/z8530.h>
41 
42 #include "uart_if.h"
43 
44 #define	DEFAULT_RCLK	307200
45 
46 /* Hack! */
47 #ifdef __powerpc__
48 #define	UART_PCLK	0
49 #else
50 #define	UART_PCLK	MCB2_PCLK
51 #endif
52 
53 /* Multiplexed I/O. */
54 static __inline void
55 uart_setmreg(struct uart_bas *bas, int reg, int val)
56 {
57 
58 	uart_setreg(bas, REG_CTRL, reg);
59 	uart_barrier(bas);
60 	uart_setreg(bas, REG_CTRL, val);
61 }
62 
63 static __inline uint8_t
64 uart_getmreg(struct uart_bas *bas, int reg)
65 {
66 
67 	uart_setreg(bas, REG_CTRL, reg);
68 	uart_barrier(bas);
69 	return (uart_getreg(bas, REG_CTRL));
70 }
71 
72 static int
73 z8530_divisor(int rclk, int baudrate)
74 {
75 	int act_baud, divisor, error;
76 
77 	if (baudrate == 0)
78 		return (-1);
79 
80 	divisor = (rclk + baudrate) / (baudrate << 1) - 2;
81 	if (divisor < 0 || divisor >= 65536)
82 		return (-1);
83 	act_baud = rclk / 2 / (divisor + 2);
84 
85 	/* 10 times error in percent: */
86 	error = ((act_baud - baudrate) * 2000 / baudrate + 1) >> 1;
87 
88 	/* 3.0% maximum error tolerance: */
89 	if (error < -30 || error > 30)
90 		return (-1);
91 
92 	return (divisor);
93 }
94 
95 static int
96 z8530_param(struct uart_bas *bas, int baudrate, int databits, int stopbits,
97     int parity, uint8_t *tpcp)
98 {
99 	int divisor;
100 	uint8_t mpm, rpc, tpc;
101 
102 	rpc = RPC_RXE;
103 	mpm = MPM_CM16;
104 	tpc = TPC_TXE | (*tpcp & (TPC_DTR | TPC_RTS));
105 
106 	if (databits >= 8) {
107 		rpc |= RPC_RB8;
108 		tpc |= TPC_TB8;
109 	} else if (databits == 7) {
110 		rpc |= RPC_RB7;
111 		tpc |= TPC_TB7;
112 	} else if (databits == 6) {
113 		rpc |= RPC_RB6;
114 		tpc |= TPC_TB6;
115 	} else {
116 		rpc |= RPC_RB5;
117 		tpc |= TPC_TB5;
118 	}
119 	mpm |= (stopbits > 1) ? MPM_SB2 : MPM_SB1;
120 	switch (parity) {
121 	case UART_PARITY_EVEN:	mpm |= MPM_PE | MPM_EVEN; break;
122 	case UART_PARITY_NONE:	break;
123 	case UART_PARITY_ODD:	mpm |= MPM_PE; break;
124 	default:		return (EINVAL);
125 	}
126 
127 	if (baudrate > 0) {
128 		divisor = z8530_divisor(bas->rclk, baudrate);
129 		if (divisor == -1)
130 			return (EINVAL);
131 	} else
132 		divisor = -1;
133 
134 	uart_setmreg(bas, WR_MCB2, UART_PCLK);
135 	uart_barrier(bas);
136 
137 	if (divisor >= 0) {
138 		uart_setmreg(bas, WR_TCL, divisor & 0xff);
139 		uart_barrier(bas);
140 		uart_setmreg(bas, WR_TCH, (divisor >> 8) & 0xff);
141 		uart_barrier(bas);
142 	}
143 
144 	uart_setmreg(bas, WR_RPC, rpc);
145 	uart_barrier(bas);
146 	uart_setmreg(bas, WR_MPM, mpm);
147 	uart_barrier(bas);
148 	uart_setmreg(bas, WR_TPC, tpc);
149 	uart_barrier(bas);
150 	uart_setmreg(bas, WR_MCB2, UART_PCLK | MCB2_BRGE);
151 	uart_barrier(bas);
152 	*tpcp = tpc;
153 	return (0);
154 }
155 
156 static int
157 z8530_setup(struct uart_bas *bas, int baudrate, int databits, int stopbits,
158     int parity)
159 {
160 	uint8_t tpc;
161 
162 	if (bas->rclk == 0)
163 		bas->rclk = DEFAULT_RCLK;
164 
165 	/* Assume we don't need to perform a full hardware reset. */
166 	switch (bas->chan) {
167 	case 1:
168 		uart_setmreg(bas, WR_MIC, MIC_NV | MIC_CRA);
169 		break;
170 	case 2:
171 		uart_setmreg(bas, WR_MIC, MIC_NV | MIC_CRB);
172 		break;
173 	}
174 	uart_barrier(bas);
175 	/* Set clock sources. */
176 	uart_setmreg(bas, WR_CMC, CMC_RC_BRG | CMC_TC_BRG);
177 	uart_setmreg(bas, WR_MCB2, UART_PCLK);
178 	uart_barrier(bas);
179 	/* Set data encoding. */
180 	uart_setmreg(bas, WR_MCB1, MCB1_NRZ);
181 	uart_barrier(bas);
182 
183 	tpc = TPC_DTR | TPC_RTS;
184 	z8530_param(bas, baudrate, databits, stopbits, parity, &tpc);
185 	return (int)tpc;
186 }
187 
188 /*
189  * Low-level UART interface.
190  */
191 static int z8530_probe(struct uart_bas *bas);
192 static void z8530_init(struct uart_bas *bas, int, int, int, int);
193 static void z8530_term(struct uart_bas *bas);
194 static void z8530_putc(struct uart_bas *bas, int);
195 static int z8530_rxready(struct uart_bas *bas);
196 static int z8530_getc(struct uart_bas *bas, struct mtx *);
197 
198 struct uart_ops uart_z8530_ops = {
199 	.probe = z8530_probe,
200 	.init = z8530_init,
201 	.term = z8530_term,
202 	.putc = z8530_putc,
203 	.rxready = z8530_rxready,
204 	.getc = z8530_getc,
205 };
206 
207 static int
208 z8530_probe(struct uart_bas *bas)
209 {
210 
211 	return (0);
212 }
213 
214 static void
215 z8530_init(struct uart_bas *bas, int baudrate, int databits, int stopbits,
216     int parity)
217 {
218 
219 	z8530_setup(bas, baudrate, databits, stopbits, parity);
220 }
221 
222 static void
223 z8530_term(struct uart_bas *bas)
224 {
225 }
226 
227 static void
228 z8530_putc(struct uart_bas *bas, int c)
229 {
230 
231 	while (!(uart_getreg(bas, REG_CTRL) & BES_TXE))
232 		;
233 	uart_setreg(bas, REG_DATA, c);
234 	uart_barrier(bas);
235 }
236 
237 static int
238 z8530_rxready(struct uart_bas *bas)
239 {
240 
241 	return ((uart_getreg(bas, REG_CTRL) & BES_RXA) != 0 ? 1 : 0);
242 }
243 
244 static int
245 z8530_getc(struct uart_bas *bas, struct mtx *hwmtx)
246 {
247 	int c;
248 
249 	uart_lock(hwmtx);
250 
251 	while (!(uart_getreg(bas, REG_CTRL) & BES_RXA)) {
252 		uart_unlock(hwmtx);
253 		DELAY(10);
254 		uart_lock(hwmtx);
255 	}
256 
257 	c = uart_getreg(bas, REG_DATA);
258 
259 	uart_unlock(hwmtx);
260 
261 	return (c);
262 }
263 
264 /*
265  * High-level UART interface.
266  */
267 struct z8530_softc {
268 	struct uart_softc base;
269 	uint8_t	tpc;
270 	uint8_t	txidle;
271 };
272 
273 static int z8530_bus_attach(struct uart_softc *);
274 static int z8530_bus_detach(struct uart_softc *);
275 static int z8530_bus_flush(struct uart_softc *, int);
276 static int z8530_bus_getsig(struct uart_softc *);
277 static int z8530_bus_ioctl(struct uart_softc *, int, intptr_t);
278 static int z8530_bus_ipend(struct uart_softc *);
279 static int z8530_bus_param(struct uart_softc *, int, int, int, int);
280 static int z8530_bus_probe(struct uart_softc *);
281 static int z8530_bus_receive(struct uart_softc *);
282 static int z8530_bus_setsig(struct uart_softc *, int);
283 static int z8530_bus_transmit(struct uart_softc *);
284 
285 static kobj_method_t z8530_methods[] = {
286 	KOBJMETHOD(uart_attach,		z8530_bus_attach),
287 	KOBJMETHOD(uart_detach,		z8530_bus_detach),
288 	KOBJMETHOD(uart_flush,		z8530_bus_flush),
289 	KOBJMETHOD(uart_getsig,		z8530_bus_getsig),
290 	KOBJMETHOD(uart_ioctl,		z8530_bus_ioctl),
291 	KOBJMETHOD(uart_ipend,		z8530_bus_ipend),
292 	KOBJMETHOD(uart_param,		z8530_bus_param),
293 	KOBJMETHOD(uart_probe,		z8530_bus_probe),
294 	KOBJMETHOD(uart_receive,	z8530_bus_receive),
295 	KOBJMETHOD(uart_setsig,		z8530_bus_setsig),
296 	KOBJMETHOD(uart_transmit,	z8530_bus_transmit),
297 	{ 0, 0 }
298 };
299 
300 struct uart_class uart_z8530_class = {
301 	"z8530 class",
302 	z8530_methods,
303 	sizeof(struct z8530_softc),
304 	.uc_range = 2,
305 	.uc_rclk = DEFAULT_RCLK
306 };
307 
308 #define	SIGCHG(c, i, s, d)				\
309 	if (c) {					\
310 		i |= (i & s) ? s : s | d;		\
311 	} else {					\
312 		i = (i & s) ? (i & ~s) | d : i;		\
313 	}
314 
315 static int
316 z8530_bus_attach(struct uart_softc *sc)
317 {
318 	struct z8530_softc *z8530 = (struct z8530_softc*)sc;
319 	struct uart_bas *bas;
320 	struct uart_devinfo *di;
321 
322 	bas = &sc->sc_bas;
323 	if (sc->sc_sysdev != NULL) {
324 		di = sc->sc_sysdev;
325 		z8530->tpc = TPC_DTR|TPC_RTS;
326 		z8530_param(bas, di->baudrate, di->databits, di->stopbits,
327 		    di->parity, &z8530->tpc);
328 	} else {
329 		z8530->tpc = z8530_setup(bas, 9600, 8, 1, UART_PARITY_NONE);
330 		z8530->tpc &= ~(TPC_DTR|TPC_RTS);
331 	}
332 	z8530->txidle = 1;	/* Report SER_INT_TXIDLE. */
333 
334 	sc->sc_rxfifosz = 3;
335 	sc->sc_txfifosz = 1;
336 
337 	(void)z8530_bus_getsig(sc);
338 
339 	uart_setmreg(bas, WR_IC, IC_BRK | IC_CTS | IC_DCD);
340 	uart_barrier(bas);
341 	uart_setmreg(bas, WR_IDT, IDT_XIE | IDT_TIE | IDT_RIA);
342 	uart_barrier(bas);
343 	uart_setmreg(bas, WR_IV, 0);
344 	uart_barrier(bas);
345 	uart_setmreg(bas, WR_TPC, z8530->tpc);
346 	uart_barrier(bas);
347 	uart_setmreg(bas, WR_MIC, MIC_NV | MIC_MIE);
348 	uart_barrier(bas);
349 	return (0);
350 }
351 
352 static int
353 z8530_bus_detach(struct uart_softc *sc)
354 {
355 
356 	return (0);
357 }
358 
359 static int
360 z8530_bus_flush(struct uart_softc *sc, int what)
361 {
362 
363 	return (0);
364 }
365 
366 static int
367 z8530_bus_getsig(struct uart_softc *sc)
368 {
369 	uint32_t new, old, sig;
370 	uint8_t bes;
371 
372 	do {
373 		old = sc->sc_hwsig;
374 		sig = old;
375 		uart_lock(sc->sc_hwmtx);
376 		bes = uart_getmreg(&sc->sc_bas, RR_BES);
377 		uart_unlock(sc->sc_hwmtx);
378 		SIGCHG(bes & BES_CTS, sig, SER_CTS, SER_DCTS);
379 		SIGCHG(bes & BES_DCD, sig, SER_DCD, SER_DDCD);
380 		SIGCHG(bes & BES_SYNC, sig, SER_DSR, SER_DDSR);
381 		new = sig & ~SER_MASK_DELTA;
382 	} while (!atomic_cmpset_32(&sc->sc_hwsig, old, new));
383 	return (sig);
384 }
385 
386 static int
387 z8530_bus_ioctl(struct uart_softc *sc, int request, intptr_t data)
388 {
389 	struct z8530_softc *z8530 = (struct z8530_softc*)sc;
390 	struct uart_bas *bas;
391 	int baudrate, divisor, error;
392 
393 	bas = &sc->sc_bas;
394 	error = 0;
395 	uart_lock(sc->sc_hwmtx);
396 	switch (request) {
397 	case UART_IOCTL_BREAK:
398 		if (data)
399 			z8530->tpc |= TPC_BRK;
400 		else
401 			z8530->tpc &= ~TPC_BRK;
402 		uart_setmreg(bas, WR_TPC, z8530->tpc);
403 		uart_barrier(bas);
404 		break;
405 	case UART_IOCTL_BAUD:
406 		divisor = uart_getmreg(bas, RR_TCH);
407 		divisor = (divisor << 8) | uart_getmreg(bas, RR_TCL);
408 		baudrate = bas->rclk / 2 / (divisor + 2);
409 		*(int*)data = baudrate;
410 		break;
411 	default:
412 		error = EINVAL;
413 		break;
414 	}
415 	uart_unlock(sc->sc_hwmtx);
416 	return (error);
417 }
418 
419 static int
420 z8530_bus_ipend(struct uart_softc *sc)
421 {
422 	struct z8530_softc *z8530 = (struct z8530_softc*)sc;
423 	struct uart_bas *bas;
424 	int ipend;
425 	uint32_t sig;
426 	uint8_t bes, ip, iv, src;
427 
428 	bas = &sc->sc_bas;
429 	ipend = 0;
430 
431 	uart_lock(sc->sc_hwmtx);
432 	switch (bas->chan) {
433 	case 1:
434 		ip = uart_getmreg(bas, RR_IP);
435 		break;
436 	case 2:	/* XXX hack!!! */
437 		iv = uart_getmreg(bas, RR_IV) & 0x0E;
438 		switch (iv) {
439 		case IV_TEB:	ip = IP_TIA; break;
440 		case IV_XSB:	ip = IP_SIA; break;
441 		case IV_RAB:	ip = IP_RIA; break;
442 		default:	ip = 0; break;
443 		}
444 		break;
445 	default:
446 		ip = 0;
447 		break;
448 	}
449 
450 	if (ip & IP_RIA)
451 		ipend |= SER_INT_RXREADY;
452 
453 	if (ip & IP_TIA) {
454 		uart_setreg(bas, REG_CTRL, CR_RSTTXI);
455 		uart_barrier(bas);
456 		if (z8530->txidle) {
457 			ipend |= SER_INT_TXIDLE;
458 			z8530->txidle = 0;	/* Mask SER_INT_TXIDLE. */
459 		}
460 	}
461 
462 	if (ip & IP_SIA) {
463 		uart_setreg(bas, REG_CTRL, CR_RSTXSI);
464 		uart_barrier(bas);
465 		bes = uart_getmreg(bas, RR_BES);
466 		if (bes & BES_BRK)
467 			ipend |= SER_INT_BREAK;
468 		sig = sc->sc_hwsig;
469 		SIGCHG(bes & BES_CTS, sig, SER_CTS, SER_DCTS);
470 		SIGCHG(bes & BES_DCD, sig, SER_DCD, SER_DDCD);
471 		SIGCHG(bes & BES_SYNC, sig, SER_DSR, SER_DDSR);
472 		if (sig & SER_MASK_DELTA)
473 			ipend |= SER_INT_SIGCHG;
474 		src = uart_getmreg(bas, RR_SRC);
475 		if (src & SRC_OVR) {
476 			uart_setreg(bas, REG_CTRL, CR_RSTERR);
477 			uart_barrier(bas);
478 			ipend |= SER_INT_OVERRUN;
479 		}
480 	}
481 
482 	if (ipend) {
483 		uart_setreg(bas, REG_CTRL, CR_RSTIUS);
484 		uart_barrier(bas);
485 	}
486 
487 	uart_unlock(sc->sc_hwmtx);
488 
489 	return (ipend);
490 }
491 
492 static int
493 z8530_bus_param(struct uart_softc *sc, int baudrate, int databits,
494     int stopbits, int parity)
495 {
496 	struct z8530_softc *z8530 = (struct z8530_softc*)sc;
497 	int error;
498 
499 	uart_lock(sc->sc_hwmtx);
500 	error = z8530_param(&sc->sc_bas, baudrate, databits, stopbits, parity,
501 	    &z8530->tpc);
502 	uart_unlock(sc->sc_hwmtx);
503 	return (error);
504 }
505 
506 static int
507 z8530_bus_probe(struct uart_softc *sc)
508 {
509 	char buf[80];
510 	int error;
511 	char ch;
512 
513 	error = z8530_probe(&sc->sc_bas);
514 	if (error)
515 		return (error);
516 
517 	ch = sc->sc_bas.chan - 1 + 'A';
518 
519 	snprintf(buf, sizeof(buf), "z8530, channel %c", ch);
520 	device_set_desc_copy(sc->sc_dev, buf);
521 	return (0);
522 }
523 
524 static int
525 z8530_bus_receive(struct uart_softc *sc)
526 {
527 	struct uart_bas *bas;
528 	int xc;
529 	uint8_t bes, src;
530 
531 	bas = &sc->sc_bas;
532 	uart_lock(sc->sc_hwmtx);
533 	bes = uart_getmreg(bas, RR_BES);
534 	while (bes & BES_RXA) {
535 		if (uart_rx_full(sc)) {
536 			sc->sc_rxbuf[sc->sc_rxput] = UART_STAT_OVERRUN;
537 			break;
538 		}
539 		xc = uart_getreg(bas, REG_DATA);
540 		uart_barrier(bas);
541 		src = uart_getmreg(bas, RR_SRC);
542 		if (src & SRC_FE)
543 			xc |= UART_STAT_FRAMERR;
544 		if (src & SRC_PE)
545 			xc |= UART_STAT_PARERR;
546 		if (src & SRC_OVR)
547 			xc |= UART_STAT_OVERRUN;
548 		uart_rx_put(sc, xc);
549 		if (src & (SRC_FE | SRC_PE | SRC_OVR)) {
550 			uart_setreg(bas, REG_CTRL, CR_RSTERR);
551 			uart_barrier(bas);
552 		}
553 		bes = uart_getmreg(bas, RR_BES);
554 	}
555 	/* Discard everything left in the Rx FIFO. */
556 	while (bes & BES_RXA) {
557 		(void)uart_getreg(bas, REG_DATA);
558 		uart_barrier(bas);
559 		src = uart_getmreg(bas, RR_SRC);
560 		if (src & (SRC_FE | SRC_PE | SRC_OVR)) {
561 			uart_setreg(bas, REG_CTRL, CR_RSTERR);
562 			uart_barrier(bas);
563 		}
564 		bes = uart_getmreg(bas, RR_BES);
565 	}
566 	uart_unlock(sc->sc_hwmtx);
567 	return (0);
568 }
569 
570 static int
571 z8530_bus_setsig(struct uart_softc *sc, int sig)
572 {
573 	struct z8530_softc *z8530 = (struct z8530_softc*)sc;
574 	struct uart_bas *bas;
575 	uint32_t new, old;
576 
577 	bas = &sc->sc_bas;
578 	do {
579 		old = sc->sc_hwsig;
580 		new = old;
581 		if (sig & SER_DDTR) {
582 			SIGCHG(sig & SER_DTR, new, SER_DTR,
583 			    SER_DDTR);
584 		}
585 		if (sig & SER_DRTS) {
586 			SIGCHG(sig & SER_RTS, new, SER_RTS,
587 			    SER_DRTS);
588 		}
589 	} while (!atomic_cmpset_32(&sc->sc_hwsig, old, new));
590 
591 	uart_lock(sc->sc_hwmtx);
592 	if (new & SER_DTR)
593 		z8530->tpc |= TPC_DTR;
594 	else
595 		z8530->tpc &= ~TPC_DTR;
596 	if (new & SER_RTS)
597 		z8530->tpc |= TPC_RTS;
598 	else
599 		z8530->tpc &= ~TPC_RTS;
600 	uart_setmreg(bas, WR_TPC, z8530->tpc);
601 	uart_barrier(bas);
602 	uart_unlock(sc->sc_hwmtx);
603 	return (0);
604 }
605 
606 static int
607 z8530_bus_transmit(struct uart_softc *sc)
608 {
609 	struct z8530_softc *z8530 = (struct z8530_softc*)sc;
610 	struct uart_bas *bas;
611 
612 	bas = &sc->sc_bas;
613 	uart_lock(sc->sc_hwmtx);
614 	while (!(uart_getmreg(bas, RR_BES) & BES_TXE))
615 		;
616 	uart_setreg(bas, REG_DATA, sc->sc_txbuf[0]);
617 	uart_barrier(bas);
618 	sc->sc_txbusy = 1;
619 	z8530->txidle = 1;	/* Report SER_INT_TXIDLE again. */
620 	uart_unlock(sc->sc_hwmtx);
621 	return (0);
622 }
623