xref: /freebsd/sys/dev/uart/uart_dev_z8530.c (revision 6af83ee0d2941d18880b6aaa2b4facd1d30c6106)
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 /* Multiplexed I/O. */
47 static __inline void
48 uart_setmreg(struct uart_bas *bas, int reg, int val)
49 {
50 
51 	uart_setreg(bas, REG_CTRL, reg);
52 	uart_barrier(bas);
53 	uart_setreg(bas, REG_CTRL, val);
54 }
55 
56 static __inline uint8_t
57 uart_getmreg(struct uart_bas *bas, int reg)
58 {
59 
60 	uart_setreg(bas, REG_CTRL, reg);
61 	uart_barrier(bas);
62 	return (uart_getreg(bas, REG_CTRL));
63 }
64 
65 static int
66 z8530_divisor(int rclk, int baudrate)
67 {
68 	int act_baud, divisor, error;
69 
70 	if (baudrate == 0)
71 		return (0);
72 
73 	divisor = (rclk + baudrate) / (baudrate << 1) - 2;
74 	if (divisor >= 65536)
75 		return (0);
76 	act_baud = rclk / 2 / (divisor + 2);
77 
78 	/* 10 times error in percent: */
79 	error = ((act_baud - baudrate) * 2000 / baudrate + 1) >> 1;
80 
81 	/* 3.0% maximum error tolerance: */
82 	if (error < -30 || error > 30)
83 		return (0);
84 
85 	return (divisor);
86 }
87 
88 static int
89 z8530_param(struct uart_bas *bas, int baudrate, int databits, int stopbits,
90     int parity, uint8_t *tpcp)
91 {
92 	int divisor;
93 	uint8_t mpm, rpc, tpc;
94 
95 	rpc = RPC_RXE;
96 	mpm = MPM_CM16;
97 	tpc = TPC_TXE | (*tpcp & (TPC_DTR | TPC_RTS));
98 
99 	if (databits >= 8) {
100 		rpc |= RPC_RB8;
101 		tpc |= TPC_TB8;
102 	} else if (databits == 7) {
103 		rpc |= RPC_RB7;
104 		tpc |= TPC_TB7;
105 	} else if (databits == 6) {
106 		rpc |= RPC_RB6;
107 		tpc |= TPC_TB6;
108 	} else {
109 		rpc |= RPC_RB5;
110 		tpc |= TPC_TB5;
111 	}
112 	mpm |= (stopbits > 1) ? MPM_SB2 : MPM_SB1;
113 	switch (parity) {
114 	case UART_PARITY_EVEN:	mpm |= MPM_PE | MPM_EVEN; break;
115 	case UART_PARITY_NONE:	break;
116 	case UART_PARITY_ODD:	mpm |= MPM_PE; break;
117 	default:		return (EINVAL);
118 	}
119 
120 	/* Set baudrate. */
121 	if (baudrate > 0) {
122 		divisor = z8530_divisor(bas->rclk, baudrate);
123 		if (divisor == 0)
124 			return (EINVAL);
125 		uart_setmreg(bas, WR_TCL, divisor & 0xff);
126 		uart_barrier(bas);
127 		uart_setmreg(bas, WR_TCH, (divisor >> 8) & 0xff);
128 		uart_barrier(bas);
129 	}
130 
131 	uart_setmreg(bas, WR_RPC, rpc);
132 	uart_barrier(bas);
133 	uart_setmreg(bas, WR_MPM, mpm);
134 	uart_barrier(bas);
135 	uart_setmreg(bas, WR_TPC, tpc);
136 	uart_barrier(bas);
137 	*tpcp = tpc;
138 	return (0);
139 }
140 
141 static int
142 z8530_setup(struct uart_bas *bas, int baudrate, int databits, int stopbits,
143     int parity)
144 {
145 	uint8_t tpc;
146 
147 	if (bas->rclk == 0)
148 		bas->rclk = DEFAULT_RCLK;
149 
150 	/* Assume we don't need to perform a full hardware reset. */
151 	switch (bas->chan) {
152 	case 1:
153 		uart_setmreg(bas, WR_MIC, MIC_NV | MIC_CRA);
154 		break;
155 	case 2:
156 		uart_setmreg(bas, WR_MIC, MIC_NV | MIC_CRB);
157 		break;
158 	}
159 	uart_barrier(bas);
160 	/* Set clock sources and enable BRG. */
161 	uart_setmreg(bas, WR_CMC, CMC_RC_BRG | CMC_TC_BRG);
162 	uart_setmreg(bas, WR_MCB2, MCB2_PCLK | MCB2_BRGE);
163 	uart_barrier(bas);
164 	/* Set data encoding. */
165 	uart_setmreg(bas, WR_MCB1, MCB1_NRZ);
166 	uart_barrier(bas);
167 
168 	tpc = TPC_DTR | TPC_RTS;
169 	z8530_param(bas, baudrate, databits, stopbits, parity, &tpc);
170 	return (int)tpc;
171 }
172 
173 /*
174  * Low-level UART interface.
175  */
176 static int z8530_probe(struct uart_bas *bas);
177 static void z8530_init(struct uart_bas *bas, int, int, int, int);
178 static void z8530_term(struct uart_bas *bas);
179 static void z8530_putc(struct uart_bas *bas, int);
180 static int z8530_poll(struct uart_bas *bas);
181 static int z8530_getc(struct uart_bas *bas);
182 
183 struct uart_ops uart_z8530_ops = {
184 	.probe = z8530_probe,
185 	.init = z8530_init,
186 	.term = z8530_term,
187 	.putc = z8530_putc,
188 	.poll = z8530_poll,
189 	.getc = z8530_getc,
190 };
191 
192 static int
193 z8530_probe(struct uart_bas *bas)
194 {
195 
196 	return (0);
197 }
198 
199 static void
200 z8530_init(struct uart_bas *bas, int baudrate, int databits, int stopbits,
201     int parity)
202 {
203 
204 	z8530_setup(bas, baudrate, databits, stopbits, parity);
205 }
206 
207 static void
208 z8530_term(struct uart_bas *bas)
209 {
210 }
211 
212 static void
213 z8530_putc(struct uart_bas *bas, int c)
214 {
215 
216 	while (!(uart_getmreg(bas, RR_BES) & BES_TXE))
217 		;
218 	uart_setreg(bas, REG_DATA, c);
219 	uart_barrier(bas);
220 }
221 
222 static int
223 z8530_poll(struct uart_bas *bas)
224 {
225 
226 	if (!(uart_getmreg(bas, RR_BES) & BES_RXA))
227 		return (-1);
228 	return (uart_getreg(bas, REG_DATA));
229 }
230 
231 static int
232 z8530_getc(struct uart_bas *bas)
233 {
234 
235 	while (!(uart_getmreg(bas, RR_BES) & BES_RXA))
236 		;
237 	return (uart_getreg(bas, REG_DATA));
238 }
239 
240 /*
241  * High-level UART interface.
242  */
243 struct z8530_softc {
244 	struct uart_softc base;
245 	uint8_t	tpc;
246 	uint8_t	txidle;
247 };
248 
249 static int z8530_bus_attach(struct uart_softc *);
250 static int z8530_bus_detach(struct uart_softc *);
251 static int z8530_bus_flush(struct uart_softc *, int);
252 static int z8530_bus_getsig(struct uart_softc *);
253 static int z8530_bus_ioctl(struct uart_softc *, int, intptr_t);
254 static int z8530_bus_ipend(struct uart_softc *);
255 static int z8530_bus_param(struct uart_softc *, int, int, int, int);
256 static int z8530_bus_probe(struct uart_softc *);
257 static int z8530_bus_receive(struct uart_softc *);
258 static int z8530_bus_setsig(struct uart_softc *, int);
259 static int z8530_bus_transmit(struct uart_softc *);
260 
261 static kobj_method_t z8530_methods[] = {
262 	KOBJMETHOD(uart_attach,		z8530_bus_attach),
263 	KOBJMETHOD(uart_detach,		z8530_bus_detach),
264 	KOBJMETHOD(uart_flush,		z8530_bus_flush),
265 	KOBJMETHOD(uart_getsig,		z8530_bus_getsig),
266 	KOBJMETHOD(uart_ioctl,		z8530_bus_ioctl),
267 	KOBJMETHOD(uart_ipend,		z8530_bus_ipend),
268 	KOBJMETHOD(uart_param,		z8530_bus_param),
269 	KOBJMETHOD(uart_probe,		z8530_bus_probe),
270 	KOBJMETHOD(uart_receive,	z8530_bus_receive),
271 	KOBJMETHOD(uart_setsig,		z8530_bus_setsig),
272 	KOBJMETHOD(uart_transmit,	z8530_bus_transmit),
273 	{ 0, 0 }
274 };
275 
276 struct uart_class uart_z8530_class = {
277 	"z8530 class",
278 	z8530_methods,
279 	sizeof(struct z8530_softc),
280 	.uc_range = 2,
281 	.uc_rclk = DEFAULT_RCLK
282 };
283 
284 #define	SIGCHG(c, i, s, d)				\
285 	if (c) {					\
286 		i |= (i & s) ? s : s | d;		\
287 	} else {					\
288 		i = (i & s) ? (i & ~s) | d : i;		\
289 	}
290 
291 static int
292 z8530_bus_attach(struct uart_softc *sc)
293 {
294 	struct z8530_softc *z8530 = (struct z8530_softc*)sc;
295 	struct uart_bas *bas;
296 	struct uart_devinfo *di;
297 
298 	bas = &sc->sc_bas;
299 	if (sc->sc_sysdev != NULL) {
300 		di = sc->sc_sysdev;
301 		z8530->tpc = TPC_DTR|TPC_RTS;
302 		z8530_param(bas, di->baudrate, di->databits, di->stopbits,
303 		    di->parity, &z8530->tpc);
304 	} else {
305 		z8530->tpc = z8530_setup(bas, 9600, 8, 1, UART_PARITY_NONE);
306 		z8530->tpc &= ~(TPC_DTR|TPC_RTS);
307 	}
308 	z8530->txidle = 1;	/* Report UART_IPEND_TXIDLE. */
309 
310 	sc->sc_rxfifosz = 3;
311 	sc->sc_txfifosz = 1;
312 
313 	(void)z8530_bus_getsig(sc);
314 
315 	uart_setmreg(bas, WR_IC, IC_BRK | IC_CTS | IC_DCD);
316 	uart_barrier(bas);
317 	uart_setmreg(bas, WR_IDT, IDT_XIE | IDT_TIE | IDT_RIA);
318 	uart_barrier(bas);
319 	uart_setmreg(bas, WR_IV, 0);
320 	uart_barrier(bas);
321 	uart_setmreg(bas, WR_TPC, z8530->tpc);
322 	uart_barrier(bas);
323 	uart_setmreg(bas, WR_MIC, MIC_NV | MIC_MIE);
324 	uart_barrier(bas);
325 	return (0);
326 }
327 
328 static int
329 z8530_bus_detach(struct uart_softc *sc)
330 {
331 
332 	return (0);
333 }
334 
335 static int
336 z8530_bus_flush(struct uart_softc *sc, int what)
337 {
338 
339 	return (0);
340 }
341 
342 static int
343 z8530_bus_getsig(struct uart_softc *sc)
344 {
345 	uint32_t new, old, sig;
346 	uint8_t bes;
347 
348 	do {
349 		old = sc->sc_hwsig;
350 		sig = old;
351 		mtx_lock_spin(&sc->sc_hwmtx);
352 		bes = uart_getmreg(&sc->sc_bas, RR_BES);
353 		mtx_unlock_spin(&sc->sc_hwmtx);
354 		SIGCHG(bes & BES_CTS, sig, SER_CTS, SER_DCTS);
355 		SIGCHG(bes & BES_DCD, sig, SER_DCD, SER_DDCD);
356 		SIGCHG(bes & BES_SYNC, sig, SER_DSR, SER_DDSR);
357 		new = sig & ~UART_SIGMASK_DELTA;
358 	} while (!atomic_cmpset_32(&sc->sc_hwsig, old, new));
359 	return (sig);
360 }
361 
362 static int
363 z8530_bus_ioctl(struct uart_softc *sc, int request, intptr_t data)
364 {
365 	struct z8530_softc *z8530 = (struct z8530_softc*)sc;
366 	struct uart_bas *bas;
367 	int error;
368 
369 	bas = &sc->sc_bas;
370 	error = 0;
371 	mtx_lock_spin(&sc->sc_hwmtx);
372 	switch (request) {
373 	case UART_IOCTL_BREAK:
374 		if (data)
375 			z8530->tpc |= TPC_BRK;
376 		else
377 			z8530->tpc &= ~TPC_BRK;
378 		uart_setmreg(bas, WR_TPC, z8530->tpc);
379 		uart_barrier(bas);
380 		break;
381 	default:
382 		error = EINVAL;
383 		break;
384 	}
385 	mtx_unlock_spin(&sc->sc_hwmtx);
386 	return (error);
387 }
388 
389 static int
390 z8530_bus_ipend(struct uart_softc *sc)
391 {
392 	struct z8530_softc *z8530 = (struct z8530_softc*)sc;
393 	struct uart_bas *bas;
394 	int ipend;
395 	uint32_t sig;
396 	uint8_t bes, ip, iv, src;
397 
398 	bas = &sc->sc_bas;
399 	ipend = 0;
400 
401 	mtx_lock_spin(&sc->sc_hwmtx);
402 	switch (bas->chan) {
403 	case 1:
404 		ip = uart_getmreg(bas, RR_IP);
405 		break;
406 	case 2:	/* XXX hack!!! */
407 		iv = uart_getmreg(bas, RR_IV) & 0x0E;
408 		switch (iv) {
409 		case IV_TEB:	ip = IP_TIA; break;
410 		case IV_XSB:	ip = IP_SIA; break;
411 		case IV_RAB:	ip = IP_RIA; break;
412 		default:	ip = 0; break;
413 		}
414 		break;
415 	default:
416 		ip = 0;
417 		break;
418 	}
419 
420 	if (ip & IP_RIA)
421 		ipend |= UART_IPEND_RXREADY;
422 
423 	if (ip & IP_TIA) {
424 		uart_setreg(bas, REG_CTRL, CR_RSTTXI);
425 		uart_barrier(bas);
426 		if (z8530->txidle) {
427 			ipend |= UART_IPEND_TXIDLE;
428 			z8530->txidle = 0;	/* Mask UART_IPEND_TXIDLE. */
429 		}
430 	}
431 
432 	if (ip & IP_SIA) {
433 		uart_setreg(bas, REG_CTRL, CR_RSTXSI);
434 		uart_barrier(bas);
435 		bes = uart_getmreg(bas, RR_BES);
436 		if (bes & BES_BRK)
437 			ipend |= UART_IPEND_BREAK;
438 		sig = sc->sc_hwsig;
439 		SIGCHG(bes & BES_CTS, sig, SER_CTS, SER_DCTS);
440 		SIGCHG(bes & BES_DCD, sig, SER_DCD, SER_DDCD);
441 		SIGCHG(bes & BES_SYNC, sig, SER_DSR, SER_DDSR);
442 		if (sig & UART_SIGMASK_DELTA)
443 			ipend |= UART_IPEND_SIGCHG;
444 		src = uart_getmreg(bas, RR_SRC);
445 		if (src & SRC_OVR) {
446 			uart_setreg(bas, REG_CTRL, CR_RSTERR);
447 			uart_barrier(bas);
448 			ipend |= UART_IPEND_OVERRUN;
449 		}
450 	}
451 
452 	if (ipend) {
453 		uart_setreg(bas, REG_CTRL, CR_RSTIUS);
454 		uart_barrier(bas);
455 	}
456 
457 	mtx_unlock_spin(&sc->sc_hwmtx);
458 
459 	return (ipend);
460 }
461 
462 static int
463 z8530_bus_param(struct uart_softc *sc, int baudrate, int databits,
464     int stopbits, int parity)
465 {
466 	struct z8530_softc *z8530 = (struct z8530_softc*)sc;
467 	int error;
468 
469 	mtx_lock_spin(&sc->sc_hwmtx);
470 	error = z8530_param(&sc->sc_bas, baudrate, databits, stopbits, parity,
471 	    &z8530->tpc);
472 	mtx_unlock_spin(&sc->sc_hwmtx);
473 	return (error);
474 }
475 
476 static int
477 z8530_bus_probe(struct uart_softc *sc)
478 {
479 	char buf[80];
480 	int error;
481 	char ch;
482 
483 	error = z8530_probe(&sc->sc_bas);
484 	if (error)
485 		return (error);
486 
487 	ch = sc->sc_bas.chan - 1 + 'A';
488 
489 	snprintf(buf, sizeof(buf), "z8530, channel %c", ch);
490 	device_set_desc_copy(sc->sc_dev, buf);
491 	return (0);
492 }
493 
494 static int
495 z8530_bus_receive(struct uart_softc *sc)
496 {
497 	struct uart_bas *bas;
498 	int xc;
499 	uint8_t bes, src;
500 
501 	bas = &sc->sc_bas;
502 	mtx_lock_spin(&sc->sc_hwmtx);
503 	bes = uart_getmreg(bas, RR_BES);
504 	while (bes & BES_RXA) {
505 		if (uart_rx_full(sc)) {
506 			sc->sc_rxbuf[sc->sc_rxput] = UART_STAT_OVERRUN;
507 			break;
508 		}
509 		xc = uart_getreg(bas, REG_DATA);
510 		uart_barrier(bas);
511 		src = uart_getmreg(bas, RR_SRC);
512 		if (src & SRC_FE)
513 			xc |= UART_STAT_FRAMERR;
514 		if (src & SRC_PE)
515 			xc |= UART_STAT_PARERR;
516 		if (src & SRC_OVR)
517 			xc |= UART_STAT_OVERRUN;
518 		uart_rx_put(sc, xc);
519 		if (src & (SRC_FE | SRC_PE | SRC_OVR)) {
520 			uart_setreg(bas, REG_CTRL, CR_RSTERR);
521 			uart_barrier(bas);
522 		}
523 		bes = uart_getmreg(bas, RR_BES);
524 	}
525 	/* Discard everything left in the Rx FIFO. */
526 	while (bes & BES_RXA) {
527 		(void)uart_getreg(bas, REG_DATA);
528 		uart_barrier(bas);
529 		src = uart_getmreg(bas, RR_SRC);
530 		if (src & (SRC_FE | SRC_PE | SRC_OVR)) {
531 			uart_setreg(bas, REG_CTRL, CR_RSTERR);
532 			uart_barrier(bas);
533 		}
534 		bes = uart_getmreg(bas, RR_BES);
535 	}
536 	mtx_unlock_spin(&sc->sc_hwmtx);
537 	return (0);
538 }
539 
540 static int
541 z8530_bus_setsig(struct uart_softc *sc, int sig)
542 {
543 	struct z8530_softc *z8530 = (struct z8530_softc*)sc;
544 	struct uart_bas *bas;
545 	uint32_t new, old;
546 
547 	bas = &sc->sc_bas;
548 	do {
549 		old = sc->sc_hwsig;
550 		new = old;
551 		if (sig & SER_DDTR) {
552 			SIGCHG(sig & SER_DTR, new, SER_DTR,
553 			    SER_DDTR);
554 		}
555 		if (sig & SER_DRTS) {
556 			SIGCHG(sig & SER_RTS, new, SER_RTS,
557 			    SER_DRTS);
558 		}
559 	} while (!atomic_cmpset_32(&sc->sc_hwsig, old, new));
560 
561 	mtx_lock_spin(&sc->sc_hwmtx);
562 	if (new & SER_DTR)
563 		z8530->tpc |= TPC_DTR;
564 	else
565 		z8530->tpc &= ~TPC_DTR;
566 	if (new & SER_RTS)
567 		z8530->tpc |= TPC_RTS;
568 	else
569 		z8530->tpc &= ~TPC_RTS;
570 	uart_setmreg(bas, WR_TPC, z8530->tpc);
571 	uart_barrier(bas);
572 	mtx_unlock_spin(&sc->sc_hwmtx);
573 	return (0);
574 }
575 
576 static int
577 z8530_bus_transmit(struct uart_softc *sc)
578 {
579 	struct z8530_softc *z8530 = (struct z8530_softc*)sc;
580 	struct uart_bas *bas;
581 
582 	bas = &sc->sc_bas;
583 	mtx_lock_spin(&sc->sc_hwmtx);
584 	while (!(uart_getmreg(bas, RR_BES) & BES_TXE))
585 		;
586 	uart_setreg(bas, REG_DATA, sc->sc_txbuf[0]);
587 	uart_barrier(bas);
588 	sc->sc_txbusy = 1;
589 	z8530->txidle = 1;	/* Report UART_IPEND_TXIDLE again. */
590 	mtx_unlock_spin(&sc->sc_hwmtx);
591 	return (0);
592 }
593