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