xref: /freebsd/sys/dev/uart/uart_dev_z8530.c (revision 3d11b6c8f01e1fca5936a11d6996448467851a94)
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 < 0 || 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, struct mtx *);
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_getreg(bas, REG_CTRL) & 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_getreg(bas, REG_CTRL) & BES_RXA))
227 		return (-1);
228 	return (uart_getreg(bas, REG_DATA));
229 }
230 
231 static int
232 z8530_getc(struct uart_bas *bas, struct mtx *hwmtx)
233 {
234 	int c;
235 
236 	uart_lock(hwmtx);
237 
238 	while (!(uart_getreg(bas, REG_CTRL) & BES_RXA)) {
239 		uart_unlock(hwmtx);
240 		DELAY(10);
241 		uart_lock(hwmtx);
242 	}
243 
244 	c = uart_getreg(bas, REG_DATA);
245 
246 	uart_unlock(hwmtx);
247 
248 	return (c);
249 }
250 
251 /*
252  * High-level UART interface.
253  */
254 struct z8530_softc {
255 	struct uart_softc base;
256 	uint8_t	tpc;
257 	uint8_t	txidle;
258 };
259 
260 static int z8530_bus_attach(struct uart_softc *);
261 static int z8530_bus_detach(struct uart_softc *);
262 static int z8530_bus_flush(struct uart_softc *, int);
263 static int z8530_bus_getsig(struct uart_softc *);
264 static int z8530_bus_ioctl(struct uart_softc *, int, intptr_t);
265 static int z8530_bus_ipend(struct uart_softc *);
266 static int z8530_bus_param(struct uart_softc *, int, int, int, int);
267 static int z8530_bus_probe(struct uart_softc *);
268 static int z8530_bus_receive(struct uart_softc *);
269 static int z8530_bus_setsig(struct uart_softc *, int);
270 static int z8530_bus_transmit(struct uart_softc *);
271 
272 static kobj_method_t z8530_methods[] = {
273 	KOBJMETHOD(uart_attach,		z8530_bus_attach),
274 	KOBJMETHOD(uart_detach,		z8530_bus_detach),
275 	KOBJMETHOD(uart_flush,		z8530_bus_flush),
276 	KOBJMETHOD(uart_getsig,		z8530_bus_getsig),
277 	KOBJMETHOD(uart_ioctl,		z8530_bus_ioctl),
278 	KOBJMETHOD(uart_ipend,		z8530_bus_ipend),
279 	KOBJMETHOD(uart_param,		z8530_bus_param),
280 	KOBJMETHOD(uart_probe,		z8530_bus_probe),
281 	KOBJMETHOD(uart_receive,	z8530_bus_receive),
282 	KOBJMETHOD(uart_setsig,		z8530_bus_setsig),
283 	KOBJMETHOD(uart_transmit,	z8530_bus_transmit),
284 	{ 0, 0 }
285 };
286 
287 struct uart_class uart_z8530_class = {
288 	"z8530 class",
289 	z8530_methods,
290 	sizeof(struct z8530_softc),
291 	.uc_range = 2,
292 	.uc_rclk = DEFAULT_RCLK
293 };
294 
295 #define	SIGCHG(c, i, s, d)				\
296 	if (c) {					\
297 		i |= (i & s) ? s : s | d;		\
298 	} else {					\
299 		i = (i & s) ? (i & ~s) | d : i;		\
300 	}
301 
302 static int
303 z8530_bus_attach(struct uart_softc *sc)
304 {
305 	struct z8530_softc *z8530 = (struct z8530_softc*)sc;
306 	struct uart_bas *bas;
307 	struct uart_devinfo *di;
308 
309 	bas = &sc->sc_bas;
310 	if (sc->sc_sysdev != NULL) {
311 		di = sc->sc_sysdev;
312 		z8530->tpc = TPC_DTR|TPC_RTS;
313 		z8530_param(bas, di->baudrate, di->databits, di->stopbits,
314 		    di->parity, &z8530->tpc);
315 	} else {
316 		z8530->tpc = z8530_setup(bas, 9600, 8, 1, UART_PARITY_NONE);
317 		z8530->tpc &= ~(TPC_DTR|TPC_RTS);
318 	}
319 	z8530->txidle = 1;	/* Report SER_INT_TXIDLE. */
320 
321 	sc->sc_rxfifosz = 3;
322 	sc->sc_txfifosz = 1;
323 
324 	(void)z8530_bus_getsig(sc);
325 
326 	uart_setmreg(bas, WR_IC, IC_BRK | IC_CTS | IC_DCD);
327 	uart_barrier(bas);
328 	uart_setmreg(bas, WR_IDT, IDT_XIE | IDT_TIE | IDT_RIA);
329 	uart_barrier(bas);
330 	uart_setmreg(bas, WR_IV, 0);
331 	uart_barrier(bas);
332 	uart_setmreg(bas, WR_TPC, z8530->tpc);
333 	uart_barrier(bas);
334 	uart_setmreg(bas, WR_MIC, MIC_NV | MIC_MIE);
335 	uart_barrier(bas);
336 	return (0);
337 }
338 
339 static int
340 z8530_bus_detach(struct uart_softc *sc)
341 {
342 
343 	return (0);
344 }
345 
346 static int
347 z8530_bus_flush(struct uart_softc *sc, int what)
348 {
349 
350 	return (0);
351 }
352 
353 static int
354 z8530_bus_getsig(struct uart_softc *sc)
355 {
356 	uint32_t new, old, sig;
357 	uint8_t bes;
358 
359 	do {
360 		old = sc->sc_hwsig;
361 		sig = old;
362 		uart_lock(sc->sc_hwmtx);
363 		bes = uart_getmreg(&sc->sc_bas, RR_BES);
364 		uart_unlock(sc->sc_hwmtx);
365 		SIGCHG(bes & BES_CTS, sig, SER_CTS, SER_DCTS);
366 		SIGCHG(bes & BES_DCD, sig, SER_DCD, SER_DDCD);
367 		SIGCHG(bes & BES_SYNC, sig, SER_DSR, SER_DDSR);
368 		new = sig & ~SER_MASK_DELTA;
369 	} while (!atomic_cmpset_32(&sc->sc_hwsig, old, new));
370 	return (sig);
371 }
372 
373 static int
374 z8530_bus_ioctl(struct uart_softc *sc, int request, intptr_t data)
375 {
376 	struct z8530_softc *z8530 = (struct z8530_softc*)sc;
377 	struct uart_bas *bas;
378 	int error;
379 
380 	bas = &sc->sc_bas;
381 	error = 0;
382 	uart_lock(sc->sc_hwmtx);
383 	switch (request) {
384 	case UART_IOCTL_BREAK:
385 		if (data)
386 			z8530->tpc |= TPC_BRK;
387 		else
388 			z8530->tpc &= ~TPC_BRK;
389 		uart_setmreg(bas, WR_TPC, z8530->tpc);
390 		uart_barrier(bas);
391 		break;
392 	default:
393 		error = EINVAL;
394 		break;
395 	}
396 	uart_unlock(sc->sc_hwmtx);
397 	return (error);
398 }
399 
400 static int
401 z8530_bus_ipend(struct uart_softc *sc)
402 {
403 	struct z8530_softc *z8530 = (struct z8530_softc*)sc;
404 	struct uart_bas *bas;
405 	int ipend;
406 	uint32_t sig;
407 	uint8_t bes, ip, iv, src;
408 
409 	bas = &sc->sc_bas;
410 	ipend = 0;
411 
412 	uart_lock(sc->sc_hwmtx);
413 	switch (bas->chan) {
414 	case 1:
415 		ip = uart_getmreg(bas, RR_IP);
416 		break;
417 	case 2:	/* XXX hack!!! */
418 		iv = uart_getmreg(bas, RR_IV) & 0x0E;
419 		switch (iv) {
420 		case IV_TEB:	ip = IP_TIA; break;
421 		case IV_XSB:	ip = IP_SIA; break;
422 		case IV_RAB:	ip = IP_RIA; break;
423 		default:	ip = 0; break;
424 		}
425 		break;
426 	default:
427 		ip = 0;
428 		break;
429 	}
430 
431 	if (ip & IP_RIA)
432 		ipend |= SER_INT_RXREADY;
433 
434 	if (ip & IP_TIA) {
435 		uart_setreg(bas, REG_CTRL, CR_RSTTXI);
436 		uart_barrier(bas);
437 		if (z8530->txidle) {
438 			ipend |= SER_INT_TXIDLE;
439 			z8530->txidle = 0;	/* Mask SER_INT_TXIDLE. */
440 		}
441 	}
442 
443 	if (ip & IP_SIA) {
444 		uart_setreg(bas, REG_CTRL, CR_RSTXSI);
445 		uart_barrier(bas);
446 		bes = uart_getmreg(bas, RR_BES);
447 		if (bes & BES_BRK)
448 			ipend |= SER_INT_BREAK;
449 		sig = sc->sc_hwsig;
450 		SIGCHG(bes & BES_CTS, sig, SER_CTS, SER_DCTS);
451 		SIGCHG(bes & BES_DCD, sig, SER_DCD, SER_DDCD);
452 		SIGCHG(bes & BES_SYNC, sig, SER_DSR, SER_DDSR);
453 		if (sig & SER_MASK_DELTA)
454 			ipend |= SER_INT_SIGCHG;
455 		src = uart_getmreg(bas, RR_SRC);
456 		if (src & SRC_OVR) {
457 			uart_setreg(bas, REG_CTRL, CR_RSTERR);
458 			uart_barrier(bas);
459 			ipend |= SER_INT_OVERRUN;
460 		}
461 	}
462 
463 	if (ipend) {
464 		uart_setreg(bas, REG_CTRL, CR_RSTIUS);
465 		uart_barrier(bas);
466 	}
467 
468 	uart_unlock(sc->sc_hwmtx);
469 
470 	return (ipend);
471 }
472 
473 static int
474 z8530_bus_param(struct uart_softc *sc, int baudrate, int databits,
475     int stopbits, int parity)
476 {
477 	struct z8530_softc *z8530 = (struct z8530_softc*)sc;
478 	int error;
479 
480 	uart_lock(sc->sc_hwmtx);
481 	error = z8530_param(&sc->sc_bas, baudrate, databits, stopbits, parity,
482 	    &z8530->tpc);
483 	uart_unlock(sc->sc_hwmtx);
484 	return (error);
485 }
486 
487 static int
488 z8530_bus_probe(struct uart_softc *sc)
489 {
490 	char buf[80];
491 	int error;
492 	char ch;
493 
494 	error = z8530_probe(&sc->sc_bas);
495 	if (error)
496 		return (error);
497 
498 	ch = sc->sc_bas.chan - 1 + 'A';
499 
500 	snprintf(buf, sizeof(buf), "z8530, channel %c", ch);
501 	device_set_desc_copy(sc->sc_dev, buf);
502 	return (0);
503 }
504 
505 static int
506 z8530_bus_receive(struct uart_softc *sc)
507 {
508 	struct uart_bas *bas;
509 	int xc;
510 	uint8_t bes, src;
511 
512 	bas = &sc->sc_bas;
513 	uart_lock(sc->sc_hwmtx);
514 	bes = uart_getmreg(bas, RR_BES);
515 	while (bes & BES_RXA) {
516 		if (uart_rx_full(sc)) {
517 			sc->sc_rxbuf[sc->sc_rxput] = UART_STAT_OVERRUN;
518 			break;
519 		}
520 		xc = uart_getreg(bas, REG_DATA);
521 		uart_barrier(bas);
522 		src = uart_getmreg(bas, RR_SRC);
523 		if (src & SRC_FE)
524 			xc |= UART_STAT_FRAMERR;
525 		if (src & SRC_PE)
526 			xc |= UART_STAT_PARERR;
527 		if (src & SRC_OVR)
528 			xc |= UART_STAT_OVERRUN;
529 		uart_rx_put(sc, xc);
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 	/* Discard everything left in the Rx FIFO. */
537 	while (bes & BES_RXA) {
538 		(void)uart_getreg(bas, REG_DATA);
539 		uart_barrier(bas);
540 		src = uart_getmreg(bas, RR_SRC);
541 		if (src & (SRC_FE | SRC_PE | SRC_OVR)) {
542 			uart_setreg(bas, REG_CTRL, CR_RSTERR);
543 			uart_barrier(bas);
544 		}
545 		bes = uart_getmreg(bas, RR_BES);
546 	}
547 	uart_unlock(sc->sc_hwmtx);
548 	return (0);
549 }
550 
551 static int
552 z8530_bus_setsig(struct uart_softc *sc, int sig)
553 {
554 	struct z8530_softc *z8530 = (struct z8530_softc*)sc;
555 	struct uart_bas *bas;
556 	uint32_t new, old;
557 
558 	bas = &sc->sc_bas;
559 	do {
560 		old = sc->sc_hwsig;
561 		new = old;
562 		if (sig & SER_DDTR) {
563 			SIGCHG(sig & SER_DTR, new, SER_DTR,
564 			    SER_DDTR);
565 		}
566 		if (sig & SER_DRTS) {
567 			SIGCHG(sig & SER_RTS, new, SER_RTS,
568 			    SER_DRTS);
569 		}
570 	} while (!atomic_cmpset_32(&sc->sc_hwsig, old, new));
571 
572 	uart_lock(sc->sc_hwmtx);
573 	if (new & SER_DTR)
574 		z8530->tpc |= TPC_DTR;
575 	else
576 		z8530->tpc &= ~TPC_DTR;
577 	if (new & SER_RTS)
578 		z8530->tpc |= TPC_RTS;
579 	else
580 		z8530->tpc &= ~TPC_RTS;
581 	uart_setmreg(bas, WR_TPC, z8530->tpc);
582 	uart_barrier(bas);
583 	uart_unlock(sc->sc_hwmtx);
584 	return (0);
585 }
586 
587 static int
588 z8530_bus_transmit(struct uart_softc *sc)
589 {
590 	struct z8530_softc *z8530 = (struct z8530_softc*)sc;
591 	struct uart_bas *bas;
592 
593 	bas = &sc->sc_bas;
594 	uart_lock(sc->sc_hwmtx);
595 	while (!(uart_getmreg(bas, RR_BES) & BES_TXE))
596 		;
597 	uart_setreg(bas, REG_DATA, sc->sc_txbuf[0]);
598 	uart_barrier(bas);
599 	sc->sc_txbusy = 1;
600 	z8530->txidle = 1;	/* Report SER_INT_TXIDLE again. */
601 	uart_unlock(sc->sc_hwmtx);
602 	return (0);
603 }
604