1/*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (c) 2003 Marcel Moolenaar
5 * All rights reserved.
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 *
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29#include <sys/cdefs.h>
30__FBSDID("$FreeBSD$");
31
32#include <sys/param.h>
33#include <sys/systm.h>
34#include <sys/bus.h>
35#include <sys/conf.h>
36#include <machine/bus.h>
37
38#include <dev/uart/uart.h>
39#include <dev/uart/uart_cpu.h>
40#include <dev/uart/uart_bus.h>
41
42#include <dev/ic/z8530.h>
43
44#include "uart_if.h"
45
46#define	DEFAULT_RCLK	307200
47
48/* Hack! */
49#ifdef __powerpc__
50#define	UART_PCLK	0
51#else
52#define	UART_PCLK	MCB2_PCLK
53#endif
54
55/* Multiplexed I/O. */
56static __inline void
57uart_setmreg(struct uart_bas *bas, int reg, int val)
58{
59
60	uart_setreg(bas, REG_CTRL, reg);
61	uart_barrier(bas);
62	uart_setreg(bas, REG_CTRL, val);
63}
64
65static __inline uint8_t
66uart_getmreg(struct uart_bas *bas, int reg)
67{
68
69	uart_setreg(bas, REG_CTRL, reg);
70	uart_barrier(bas);
71	return (uart_getreg(bas, REG_CTRL));
72}
73
74static int
75z8530_divisor(int rclk, int baudrate)
76{
77	int act_baud, divisor, error;
78
79	if (baudrate == 0)
80		return (-1);
81
82	divisor = (rclk + baudrate) / (baudrate << 1) - 2;
83	if (divisor < 0 || divisor >= 65536)
84		return (-1);
85	act_baud = rclk / 2 / (divisor + 2);
86
87	/* 10 times error in percent: */
88	error = ((act_baud - baudrate) * 2000 / baudrate + 1) >> 1;
89
90	/* 3.0% maximum error tolerance: */
91	if (error < -30 || error > 30)
92		return (-1);
93
94	return (divisor);
95}
96
97static int
98z8530_param(struct uart_bas *bas, int baudrate, int databits, int stopbits,
99    int parity, uint8_t *tpcp)
100{
101	int divisor;
102	uint8_t mpm, rpc, tpc;
103
104	rpc = RPC_RXE;
105	mpm = MPM_CM16;
106	tpc = TPC_TXE | (*tpcp & (TPC_DTR | TPC_RTS));
107
108	if (databits >= 8) {
109		rpc |= RPC_RB8;
110		tpc |= TPC_TB8;
111	} else if (databits == 7) {
112		rpc |= RPC_RB7;
113		tpc |= TPC_TB7;
114	} else if (databits == 6) {
115		rpc |= RPC_RB6;
116		tpc |= TPC_TB6;
117	} else {
118		rpc |= RPC_RB5;
119		tpc |= TPC_TB5;
120	}
121	mpm |= (stopbits > 1) ? MPM_SB2 : MPM_SB1;
122	switch (parity) {
123	case UART_PARITY_EVEN:	mpm |= MPM_PE | MPM_EVEN; break;
124	case UART_PARITY_NONE:	break;
125	case UART_PARITY_ODD:	mpm |= MPM_PE; break;
126	default:		return (EINVAL);
127	}
128
129	if (baudrate > 0) {
130		divisor = z8530_divisor(bas->rclk, baudrate);
131		if (divisor == -1)
132			return (EINVAL);
133	} else
134		divisor = -1;
135
136	uart_setmreg(bas, WR_MCB2, UART_PCLK);
137	uart_barrier(bas);
138
139	if (divisor >= 0) {
140		uart_setmreg(bas, WR_TCL, divisor & 0xff);
141		uart_barrier(bas);
142		uart_setmreg(bas, WR_TCH, (divisor >> 8) & 0xff);
143		uart_barrier(bas);
144	}
145
146	uart_setmreg(bas, WR_RPC, rpc);
147	uart_barrier(bas);
148	uart_setmreg(bas, WR_MPM, mpm);
149	uart_barrier(bas);
150	uart_setmreg(bas, WR_TPC, tpc);
151	uart_barrier(bas);
152	uart_setmreg(bas, WR_MCB2, UART_PCLK | MCB2_BRGE);
153	uart_barrier(bas);
154	*tpcp = tpc;
155	return (0);
156}
157
158static int
159z8530_setup(struct uart_bas *bas, int baudrate, int databits, int stopbits,
160    int parity)
161{
162	uint8_t tpc;
163
164	if (bas->rclk == 0)
165		bas->rclk = DEFAULT_RCLK;
166
167	/* Assume we don't need to perform a full hardware reset. */
168	switch (bas->chan) {
169	case 1:
170		uart_setmreg(bas, WR_MIC, MIC_NV | MIC_CRA);
171		break;
172	case 2:
173		uart_setmreg(bas, WR_MIC, MIC_NV | MIC_CRB);
174		break;
175	}
176	uart_barrier(bas);
177	/* Set clock sources. */
178	uart_setmreg(bas, WR_CMC, CMC_RC_BRG | CMC_TC_BRG);
179	uart_setmreg(bas, WR_MCB2, UART_PCLK);
180	uart_barrier(bas);
181	/* Set data encoding. */
182	uart_setmreg(bas, WR_MCB1, MCB1_NRZ);
183	uart_barrier(bas);
184
185	tpc = TPC_DTR | TPC_RTS;
186	z8530_param(bas, baudrate, databits, stopbits, parity, &tpc);
187	return (int)tpc;
188}
189
190/*
191 * Low-level UART interface.
192 */
193static int z8530_probe(struct uart_bas *bas);
194static void z8530_init(struct uart_bas *bas, int, int, int, int);
195static void z8530_term(struct uart_bas *bas);
196static void z8530_putc(struct uart_bas *bas, int);
197static int z8530_rxready(struct uart_bas *bas);
198static int z8530_getc(struct uart_bas *bas, struct mtx *);
199
200static struct uart_ops uart_z8530_ops = {
201	.probe = z8530_probe,
202	.init = z8530_init,
203	.term = z8530_term,
204	.putc = z8530_putc,
205	.rxready = z8530_rxready,
206	.getc = z8530_getc,
207};
208
209static int
210z8530_probe(struct uart_bas *bas)
211{
212
213	return (0);
214}
215
216static void
217z8530_init(struct uart_bas *bas, int baudrate, int databits, int stopbits,
218    int parity)
219{
220
221	z8530_setup(bas, baudrate, databits, stopbits, parity);
222}
223
224static void
225z8530_term(struct uart_bas *bas)
226{
227}
228
229static void
230z8530_putc(struct uart_bas *bas, int c)
231{
232
233	while (!(uart_getreg(bas, REG_CTRL) & BES_TXE))
234		;
235	uart_setreg(bas, REG_DATA, c);
236	uart_barrier(bas);
237}
238
239static int
240z8530_rxready(struct uart_bas *bas)
241{
242
243	return ((uart_getreg(bas, REG_CTRL) & BES_RXA) != 0 ? 1 : 0);
244}
245
246static int
247z8530_getc(struct uart_bas *bas, struct mtx *hwmtx)
248{
249	int c;
250
251	uart_lock(hwmtx);
252
253	while (!(uart_getreg(bas, REG_CTRL) & BES_RXA)) {
254		uart_unlock(hwmtx);
255		DELAY(10);
256		uart_lock(hwmtx);
257	}
258
259	c = uart_getreg(bas, REG_DATA);
260
261	uart_unlock(hwmtx);
262
263	return (c);
264}
265
266/*
267 * High-level UART interface.
268 */
269struct z8530_softc {
270	struct uart_softc base;
271	uint8_t	tpc;
272	uint8_t	txidle;
273};
274
275static int z8530_bus_attach(struct uart_softc *);
276static int z8530_bus_detach(struct uart_softc *);
277static int z8530_bus_flush(struct uart_softc *, int);
278static int z8530_bus_getsig(struct uart_softc *);
279static int z8530_bus_ioctl(struct uart_softc *, int, intptr_t);
280static int z8530_bus_ipend(struct uart_softc *);
281static int z8530_bus_param(struct uart_softc *, int, int, int, int);
282static int z8530_bus_probe(struct uart_softc *);
283static int z8530_bus_receive(struct uart_softc *);
284static int z8530_bus_setsig(struct uart_softc *, int);
285static int z8530_bus_transmit(struct uart_softc *);
286static void z8530_bus_grab(struct uart_softc *);
287static void z8530_bus_ungrab(struct uart_softc *);
288
289static kobj_method_t z8530_methods[] = {
290	KOBJMETHOD(uart_attach,		z8530_bus_attach),
291	KOBJMETHOD(uart_detach,		z8530_bus_detach),
292	KOBJMETHOD(uart_flush,		z8530_bus_flush),
293	KOBJMETHOD(uart_getsig,		z8530_bus_getsig),
294	KOBJMETHOD(uart_ioctl,		z8530_bus_ioctl),
295	KOBJMETHOD(uart_ipend,		z8530_bus_ipend),
296	KOBJMETHOD(uart_param,		z8530_bus_param),
297	KOBJMETHOD(uart_probe,		z8530_bus_probe),
298	KOBJMETHOD(uart_receive,	z8530_bus_receive),
299	KOBJMETHOD(uart_setsig,		z8530_bus_setsig),
300	KOBJMETHOD(uart_transmit,	z8530_bus_transmit),
301	KOBJMETHOD(uart_grab,		z8530_bus_grab),
302	KOBJMETHOD(uart_ungrab,		z8530_bus_ungrab),
303	{ 0, 0 }
304};
305
306struct uart_class uart_z8530_class = {
307	"z8530",
308	z8530_methods,
309	sizeof(struct z8530_softc),
310	.uc_ops = &uart_z8530_ops,
311	.uc_range = 2,
312	.uc_rclk = DEFAULT_RCLK,
313	.uc_rshift = 0
314};
315
316#define	SIGCHG(c, i, s, d)				\
317	if (c) {					\
318		i |= (i & s) ? s : s | d;		\
319	} else {					\
320		i = (i & s) ? (i & ~s) | d : i;		\
321	}
322
323static int
324z8530_bus_attach(struct uart_softc *sc)
325{
326	struct z8530_softc *z8530 = (struct z8530_softc*)sc;
327	struct uart_bas *bas;
328	struct uart_devinfo *di;
329
330	bas = &sc->sc_bas;
331	if (sc->sc_sysdev != NULL) {
332		di = sc->sc_sysdev;
333		z8530->tpc = TPC_DTR|TPC_RTS;
334		z8530_param(bas, di->baudrate, di->databits, di->stopbits,
335		    di->parity, &z8530->tpc);
336	} else {
337		z8530->tpc = z8530_setup(bas, 9600, 8, 1, UART_PARITY_NONE);
338		z8530->tpc &= ~(TPC_DTR|TPC_RTS);
339	}
340	z8530->txidle = 1;	/* Report SER_INT_TXIDLE. */
341
342	(void)z8530_bus_getsig(sc);
343
344	uart_setmreg(bas, WR_IC, IC_BRK | IC_CTS | IC_DCD);
345	uart_barrier(bas);
346	uart_setmreg(bas, WR_IDT, IDT_XIE | IDT_TIE | IDT_RIA);
347	uart_barrier(bas);
348	uart_setmreg(bas, WR_IV, 0);
349	uart_barrier(bas);
350	uart_setmreg(bas, WR_TPC, z8530->tpc);
351	uart_barrier(bas);
352	uart_setmreg(bas, WR_MIC, MIC_NV | MIC_MIE);
353	uart_barrier(bas);
354	return (0);
355}
356
357static int
358z8530_bus_detach(struct uart_softc *sc)
359{
360
361	return (0);
362}
363
364static int
365z8530_bus_flush(struct uart_softc *sc, int what)
366{
367
368	return (0);
369}
370
371static int
372z8530_bus_getsig(struct uart_softc *sc)
373{
374	uint32_t new, old, sig;
375	uint8_t bes;
376
377	do {
378		old = sc->sc_hwsig;
379		sig = old;
380		uart_lock(sc->sc_hwmtx);
381		bes = uart_getmreg(&sc->sc_bas, RR_BES);
382		uart_unlock(sc->sc_hwmtx);
383		SIGCHG(bes & BES_CTS, sig, SER_CTS, SER_DCTS);
384		SIGCHG(bes & BES_DCD, sig, SER_DCD, SER_DDCD);
385		SIGCHG(bes & BES_SYNC, sig, SER_DSR, SER_DDSR);
386		new = sig & ~SER_MASK_DELTA;
387	} while (!atomic_cmpset_32(&sc->sc_hwsig, old, new));
388	return (sig);
389}
390
391static int
392z8530_bus_ioctl(struct uart_softc *sc, int request, intptr_t data)
393{
394	struct z8530_softc *z8530 = (struct z8530_softc*)sc;
395	struct uart_bas *bas;
396	int baudrate, divisor, error;
397
398	bas = &sc->sc_bas;
399	error = 0;
400	uart_lock(sc->sc_hwmtx);
401	switch (request) {
402	case UART_IOCTL_BREAK:
403		if (data)
404			z8530->tpc |= TPC_BRK;
405		else
406			z8530->tpc &= ~TPC_BRK;
407		uart_setmreg(bas, WR_TPC, z8530->tpc);
408		uart_barrier(bas);
409		break;
410	case UART_IOCTL_BAUD:
411		divisor = uart_getmreg(bas, RR_TCH);
412		divisor = (divisor << 8) | uart_getmreg(bas, RR_TCL);
413		baudrate = bas->rclk / 2 / (divisor + 2);
414		*(int*)data = baudrate;
415		break;
416	default:
417		error = EINVAL;
418		break;
419	}
420	uart_unlock(sc->sc_hwmtx);
421	return (error);
422}
423
424static int
425z8530_bus_ipend(struct uart_softc *sc)
426{
427	struct z8530_softc *z8530 = (struct z8530_softc*)sc;
428	struct uart_bas *bas;
429	int ipend;
430	uint32_t sig;
431	uint8_t bes, ip, iv, src;
432
433	bas = &sc->sc_bas;
434	ipend = 0;
435
436	uart_lock(sc->sc_hwmtx);
437	switch (bas->chan) {
438	case 1:
439		ip = uart_getmreg(bas, RR_IP);
440		break;
441	case 2:	/* XXX hack!!! */
442		iv = uart_getmreg(bas, RR_IV) & 0x0E;
443		switch (iv) {
444		case IV_TEB:	ip = IP_TIA; break;
445		case IV_XSB:	ip = IP_SIA; break;
446		case IV_RAB:	ip = IP_RIA; break;
447		default:	ip = 0; break;
448		}
449		break;
450	default:
451		ip = 0;
452		break;
453	}
454
455	if (ip & IP_RIA)
456		ipend |= SER_INT_RXREADY;
457
458	if (ip & IP_TIA) {
459		uart_setreg(bas, REG_CTRL, CR_RSTTXI);
460		uart_barrier(bas);
461		if (z8530->txidle) {
462			ipend |= SER_INT_TXIDLE;
463			z8530->txidle = 0;	/* Mask SER_INT_TXIDLE. */
464		}
465	}
466
467	if (ip & IP_SIA) {
468		uart_setreg(bas, REG_CTRL, CR_RSTXSI);
469		uart_barrier(bas);
470		bes = uart_getmreg(bas, RR_BES);
471		if (bes & BES_BRK)
472			ipend |= SER_INT_BREAK;
473		sig = sc->sc_hwsig;
474		SIGCHG(bes & BES_CTS, sig, SER_CTS, SER_DCTS);
475		SIGCHG(bes & BES_DCD, sig, SER_DCD, SER_DDCD);
476		SIGCHG(bes & BES_SYNC, sig, SER_DSR, SER_DDSR);
477		if (sig & SER_MASK_DELTA)
478			ipend |= SER_INT_SIGCHG;
479		src = uart_getmreg(bas, RR_SRC);
480		if (src & SRC_OVR) {
481			uart_setreg(bas, REG_CTRL, CR_RSTERR);
482			uart_barrier(bas);
483			ipend |= SER_INT_OVERRUN;
484		}
485	}
486
487	if (ipend) {
488		uart_setreg(bas, REG_CTRL, CR_RSTIUS);
489		uart_barrier(bas);
490	}
491
492	uart_unlock(sc->sc_hwmtx);
493
494	return (ipend);
495}
496
497static int
498z8530_bus_param(struct uart_softc *sc, int baudrate, int databits,
499    int stopbits, int parity)
500{
501	struct z8530_softc *z8530 = (struct z8530_softc*)sc;
502	int error;
503
504	uart_lock(sc->sc_hwmtx);
505	error = z8530_param(&sc->sc_bas, baudrate, databits, stopbits, parity,
506	    &z8530->tpc);
507	uart_unlock(sc->sc_hwmtx);
508	return (error);
509}
510
511static int
512z8530_bus_probe(struct uart_softc *sc)
513{
514	char buf[80];
515	int error;
516	char ch;
517
518	error = z8530_probe(&sc->sc_bas);
519	if (error)
520		return (error);
521
522	sc->sc_rxfifosz = 3;
523	sc->sc_txfifosz = 1;
524
525	ch = sc->sc_bas.chan - 1 + 'A';
526
527	snprintf(buf, sizeof(buf), "z8530, channel %c", ch);
528	device_set_desc_copy(sc->sc_dev, buf);
529	return (0);
530}
531
532static int
533z8530_bus_receive(struct uart_softc *sc)
534{
535	struct uart_bas *bas;
536	int xc;
537	uint8_t bes, src;
538
539	bas = &sc->sc_bas;
540	uart_lock(sc->sc_hwmtx);
541	bes = uart_getmreg(bas, RR_BES);
542	while (bes & BES_RXA) {
543		if (uart_rx_full(sc)) {
544			sc->sc_rxbuf[sc->sc_rxput] = UART_STAT_OVERRUN;
545			break;
546		}
547		xc = uart_getreg(bas, REG_DATA);
548		uart_barrier(bas);
549		src = uart_getmreg(bas, RR_SRC);
550		if (src & SRC_FE)
551			xc |= UART_STAT_FRAMERR;
552		if (src & SRC_PE)
553			xc |= UART_STAT_PARERR;
554		if (src & SRC_OVR)
555			xc |= UART_STAT_OVERRUN;
556		uart_rx_put(sc, xc);
557		if (src & (SRC_FE | SRC_PE | SRC_OVR)) {
558			uart_setreg(bas, REG_CTRL, CR_RSTERR);
559			uart_barrier(bas);
560		}
561		bes = uart_getmreg(bas, RR_BES);
562	}
563	/* Discard everything left in the Rx FIFO. */
564	while (bes & BES_RXA) {
565		(void)uart_getreg(bas, REG_DATA);
566		uart_barrier(bas);
567		src = uart_getmreg(bas, RR_SRC);
568		if (src & (SRC_FE | SRC_PE | SRC_OVR)) {
569			uart_setreg(bas, REG_CTRL, CR_RSTERR);
570			uart_barrier(bas);
571		}
572		bes = uart_getmreg(bas, RR_BES);
573	}
574	uart_unlock(sc->sc_hwmtx);
575	return (0);
576}
577
578static int
579z8530_bus_setsig(struct uart_softc *sc, int sig)
580{
581	struct z8530_softc *z8530 = (struct z8530_softc*)sc;
582	struct uart_bas *bas;
583	uint32_t new, old;
584
585	bas = &sc->sc_bas;
586	do {
587		old = sc->sc_hwsig;
588		new = old;
589		if (sig & SER_DDTR) {
590			SIGCHG(sig & SER_DTR, new, SER_DTR,
591			    SER_DDTR);
592		}
593		if (sig & SER_DRTS) {
594			SIGCHG(sig & SER_RTS, new, SER_RTS,
595			    SER_DRTS);
596		}
597	} while (!atomic_cmpset_32(&sc->sc_hwsig, old, new));
598
599	uart_lock(sc->sc_hwmtx);
600	if (new & SER_DTR)
601		z8530->tpc |= TPC_DTR;
602	else
603		z8530->tpc &= ~TPC_DTR;
604	if (new & SER_RTS)
605		z8530->tpc |= TPC_RTS;
606	else
607		z8530->tpc &= ~TPC_RTS;
608	uart_setmreg(bas, WR_TPC, z8530->tpc);
609	uart_barrier(bas);
610	uart_unlock(sc->sc_hwmtx);
611	return (0);
612}
613
614static int
615z8530_bus_transmit(struct uart_softc *sc)
616{
617	struct z8530_softc *z8530 = (struct z8530_softc*)sc;
618	struct uart_bas *bas;
619
620	bas = &sc->sc_bas;
621	uart_lock(sc->sc_hwmtx);
622	while (!(uart_getmreg(bas, RR_BES) & BES_TXE))
623		;
624	uart_setreg(bas, REG_DATA, sc->sc_txbuf[0]);
625	uart_barrier(bas);
626	sc->sc_txbusy = 1;
627	z8530->txidle = 1;	/* Report SER_INT_TXIDLE again. */
628	uart_unlock(sc->sc_hwmtx);
629	return (0);
630}
631
632static void
633z8530_bus_grab(struct uart_softc *sc)
634{
635	struct uart_bas *bas;
636
637	bas = &sc->sc_bas;
638	uart_lock(sc->sc_hwmtx);
639	uart_setmreg(bas, WR_IDT, IDT_XIE | IDT_TIE);
640	uart_barrier(bas);
641	uart_unlock(sc->sc_hwmtx);
642}
643
644static void
645z8530_bus_ungrab(struct uart_softc *sc)
646{
647	struct uart_bas *bas;
648
649	bas = &sc->sc_bas;
650	uart_lock(sc->sc_hwmtx);
651	uart_setmreg(bas, WR_IDT, IDT_XIE | IDT_TIE | IDT_RIA);
652	uart_barrier(bas);
653	uart_unlock(sc->sc_hwmtx);
654}
655