xref: /netbsd-src/sys/arch/news68k/dev/zs.c (revision d710132b4b8ce7f7cccaaf660cb16aa16b4077a0)
1 /*	$NetBSD: zs.c,v 1.17 2003/05/01 23:25:52 tsutsui Exp $	*/
2 
3 /*-
4  * Copyright (c) 1996 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Gordon W. Ross.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *        This product includes software developed by the NetBSD
21  *        Foundation, Inc. and its contributors.
22  * 4. Neither the name of The NetBSD Foundation nor the names of its
23  *    contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36  * POSSIBILITY OF SUCH DAMAGE.
37  */
38 
39 /*
40  * Zilog Z8530 Dual UART driver (machine-dependent part)
41  *
42  * Runs two serial lines per chip using slave drivers.
43  * Plain tty/async lines use the zs_async slave.
44  */
45 
46 /*
47  * news68k/dev/zs.c - based on {newsmips,x68k,mvme68k}/dev/zs.c
48  */
49 
50 #include "opt_ddb.h"
51 
52 #include <sys/param.h>
53 #include <sys/systm.h>
54 #include <sys/conf.h>
55 #include <sys/device.h>
56 #include <sys/tty.h>
57 
58 #include <machine/cpu.h>
59 #include <machine/z8530var.h>
60 
61 #include <dev/cons.h>
62 #include <dev/ic/z8530reg.h>
63 
64 #include <news68k/dev/hbvar.h>
65 
66 int  zs_getc(void *);
67 void zs_putc(void *, int);
68 
69 /*
70  * Some warts needed by z8530tty.c -
71  * The default parity REALLY needs to be the same as the PROM uses,
72  * or you can not see messages done with printf during boot-up...
73  */
74 int zs_def_cflag = (CREAD | CS8 | HUPCL);
75 
76 /*
77  * The news68k machines use three different clocks for the ZS chips.
78  */
79 #define NPCLK	3
80 #define PCLK0	(9600 * 416)	/*  news1700: 3.9936MHz */
81 #define PCLK1	(9600 * 512)	/*  news1200: 4.9152MHz */
82 #define PCLK2	(9600 * 384)	/*  external: 3.6864MHz */
83 
84 static const u_int pclk[NPCLK] = {
85 	PCLK0,
86 	PCLK1,
87 	PCLK2,
88 };
89 
90 /*
91  * Define interrupt levels.
92  */
93 #define ZSHARD_PRI 5
94 #define ZS_IVECT 64
95 
96 #define ZS_DELAY() /* delay(2) */
97 
98 /* The layout of this is hardware-dependent (padding, order). */
99 struct zschan {
100 	volatile u_char	zc_csr;		/* ctrl,status, and indirect access */
101 	volatile u_char	zc_data;	/* data */
102 };
103 struct zsdevice {
104 	/* Yes, they are backwards. */
105 	struct	zschan zs_chan_b;
106 	struct	zschan zs_chan_a;
107 };
108 
109 static u_char zs_sir;
110 
111 /* Default speed for all channels */
112 static int zs_defspeed = 9600;
113 
114 /* console status from cninit */
115 static struct zs_chanstate zs_conschan_store;
116 static struct zs_chanstate *zs_conschan;
117 static struct zschan *zc_cons;
118 
119 static u_char zs_init_reg[16] = {
120 	0,	/* 0: CMD (reset, etc.) */
121 	0,	/* 1: No interrupts yet. */
122 	ZS_IVECT,	/* IVECT */
123 	ZSWR3_RX_8 | ZSWR3_RX_ENABLE,
124 	ZSWR4_CLK_X16 | ZSWR4_ONESB | ZSWR4_EVENP,
125 	ZSWR5_TX_8 | ZSWR5_TX_ENABLE,
126 	0,	/* 6: TXSYNC/SYNCLO */
127 	0,	/* 7: RXSYNC/SYNCHI */
128 	0,	/* 8: alias for data port */
129 	ZSWR9_MASTER_IE,
130 	0,	/*10: Misc. TX/RX control bits */
131 	ZSWR11_TXCLK_BAUD | ZSWR11_RXCLK_BAUD,
132 	BPS_TO_TCONST((PCLK0/16), 9600), /*12: BAUDLO (default=9600) */
133 	0,			/*13: BAUDHI (default=9600) */
134 	ZSWR14_BAUD_ENA | ZSWR14_BAUD_FROM_PCLK,
135 	ZSWR15_BREAK_IE,
136 };
137 
138 
139 /****************************************************************
140  * Autoconfig
141  ****************************************************************/
142 
143 /* Definition of the driver for autoconfig. */
144 static int  zs_match(struct device *, struct cfdata *, void *);
145 static void zs_attach(struct device *, struct device *, void *);
146 static int  zs_print(void *, const char *name);
147 
148 CFATTACH_DECL(zsc, sizeof(struct zsc_softc),
149     zs_match, zs_attach, NULL, NULL);
150 
151 extern struct cfdriver zsc_cd;
152 
153 static int zshard(void *);
154 void zssoft(void *);
155 #if 0
156 static int zs_get_speed(struct zs_chanstate *);
157 #endif
158 
159 /*
160  * Is the zs chip present?
161  */
162 static int
163 zs_match(parent, cf, aux)
164 	struct device *parent;
165 	struct cfdata *cf;
166 	void *aux;
167 {
168 	struct hb_attach_args *ha = aux;
169 	u_int addr;
170 
171 	if (strcmp(ha->ha_name, "zsc"))
172 		return 0;
173 
174 	/* XXX no default address */
175 	if (ha->ha_address == (u_int)-1)
176 		return 0;
177 
178 	addr = IIOV(ha->ha_address);
179 	/* This returns -1 on a fault (bus error). */
180 	if (badaddr((void *)addr, 1))
181 		return 0;
182 
183 	return 1;
184 }
185 
186 /*
187  * Attach a found zs.
188  */
189 static void
190 zs_attach(parent, self, aux)
191 	struct device *parent;
192 	struct device *self;
193 	void *aux;
194 {
195 	struct zsc_softc *zsc = (void *) self;
196 	struct cfdata *cf = self->dv_cfdata;
197 	struct hb_attach_args *ha = aux;
198 	struct zsc_attach_args zsc_args;
199 	struct zsdevice *zs;
200 	struct zschan *zc;
201 	struct zs_chanstate *cs;
202 	int s, channel, clk;
203 
204 	zs = (void *)IIOV(ha->ha_address);
205 
206 	clk = cf->cf_flags;
207 	if (clk < 0 || clk >= NPCLK)
208 		clk = 0;
209 
210 	printf("\n");
211 
212 	/*
213 	 * Initialize software state for each channel.
214 	 */
215 	for (channel = 0; channel < 2; channel++) {
216 		zsc_args.channel = channel;
217 		cs = &zsc->zsc_cs_store[channel];
218 		simple_lock_init(&cs->cs_lock);
219 
220 		zsc->zsc_cs[channel] = cs;
221 		zc = (channel == 0) ? &zs->zs_chan_a : &zs->zs_chan_b;
222 
223 		if (ha->ha_vect != -1)
224 			zs_init_reg[2] = ha->ha_vect;
225 
226 		if (zc == zc_cons) {
227 			memcpy(cs, zs_conschan, sizeof(struct zs_chanstate));
228 			zs_conschan = cs;
229 			zsc_args.hwflags = ZS_HWFLAG_CONSOLE;
230 		} else {
231 			cs->cs_reg_csr  = &zc->zc_csr;
232 			cs->cs_reg_data = &zc->zc_data;
233 			memcpy(cs->cs_creg, zs_init_reg, 16);
234 			memcpy(cs->cs_preg, zs_init_reg, 16);
235 			cs->cs_defspeed = zs_defspeed;
236 			zsc_args.hwflags = 0;
237 		}
238 
239 		cs->cs_defcflag = zs_def_cflag;
240 
241 		cs->cs_channel = channel;
242 		cs->cs_private = NULL;
243 		cs->cs_ops = &zsops_null;
244 		cs->cs_brg_clk = pclk[clk] / 16;
245 
246 		/* Make these correspond to cs_defcflag (-crtscts) */
247 		cs->cs_rr0_dcd = ZSRR0_DCD;
248 		cs->cs_rr0_cts = 0;
249 		cs->cs_wr5_dtr = ZSWR5_DTR | ZSWR5_RTS;
250 		cs->cs_wr5_rts = 0;
251 
252 		/*
253 		 * Clear the master interrupt enable.
254 		 * The INTENA is common to both channels,
255 		 * so just do it on the A channel.
256 		 */
257 		if (channel == 0) {
258 			s = splhigh();
259 			zs_write_reg(cs, 9, 0);
260 			splx(s);
261 		}
262 
263 		/*
264 		 * Look for a child driver for this channel.
265 		 * The child attach will setup the hardware.
266 		 */
267 		if (!config_found(self, (void *)&zsc_args, zs_print)) {
268 			/* No sub-driver.  Just reset it. */
269 			u_char reset = (channel == 0) ?
270 				ZSWR9_A_RESET : ZSWR9_B_RESET;
271 			s = splhigh();
272 			zs_write_reg(cs,  9, reset);
273 			splx(s);
274 		}
275 	}
276 
277 	/*
278 	 * Now safe to install interrupt handlers.
279 	 */
280 	hb_intr_establish(zs_init_reg[2], zshard, ZSHARD_PRI, zsc);
281 
282 	/*
283 	 * Set the master interrupt enable and interrupt vector.
284 	 * (common to both channels, do it on A)
285 	 */
286 	cs = zsc->zsc_cs[0];
287 	s = splhigh();
288 	/* interrupt vector */
289 	zs_write_reg(cs, 2, zs_init_reg[2]);
290 	/* master interrupt control (enable) */
291 	zs_write_reg(cs, 9, zs_init_reg[9]);
292 	splx(s);
293 
294 	if (zs_sir == 0)
295 		zs_sir = allocate_sir(zssoft, zsc);
296 }
297 
298 static int
299 zs_print(aux, name)
300 	void *aux;
301 	const char *name;
302 {
303 	struct zsc_attach_args *args = aux;
304 
305 	if (name != NULL)
306 		aprint_normal("%s: ", name);
307 
308 	if (args->channel != -1)
309 		aprint_normal(" channel %d", args->channel);
310 
311 	return UNCONF;
312 }
313 
314 /*
315  * For news68k-port, we don't use autovectored interrupt.
316  * We do not need to look at all of the zs chips.
317  */
318 static int
319 zshard(arg)
320 	void *arg;
321 {
322 	struct zsc_softc *zsc = arg;
323 	int rval;
324 
325 	rval = zsc_intr_hard(zsc);
326 
327 	/* We are at splzs here, so no need to lock. */
328 	if (zsc->zsc_cs[0]->cs_softreq || zsc->zsc_cs[1]->cs_softreq) {
329 		setsoftint(zs_sir);
330 	}
331 
332 	return rval;
333 }
334 
335 /*
336  * Shared among the all chips. We have to look at all of them.
337  */
338 void
339 zssoft(arg)
340 	void *arg;
341 {
342 	struct zsc_softc *zsc;
343 	int s, unit;
344 
345 	/* Make sure we call the tty layer at spltty. */
346 	s = spltty();
347 	for (unit = 0; unit < zsc_cd.cd_ndevs; unit++) {
348 		zsc = zsc_cd.cd_devs[unit];
349 		if (zsc == NULL)
350 			continue;
351 		(void) zsc_intr_soft(zsc);
352 	}
353 	splx(s);
354 }
355 
356 /*
357  * Compute the current baud rate given a ZS channel.
358  */
359 #if 0
360 static int
361 zs_get_speed(cs)
362 	struct zs_chanstate *cs;
363 {
364 	int tconst;
365 
366 	tconst = zs_read_reg(cs, 12);
367 	tconst |= zs_read_reg(cs, 13) << 8;
368 	return TCONST_TO_BPS(cs->cs_brg_clk, tconst);
369 }
370 #endif
371 
372 /*
373  * MD functions for setting the baud rate and control modes.
374  */
375 int
376 zs_set_speed(cs, bps)
377 	struct zs_chanstate *cs;
378 	int bps;	/* bits per second */
379 {
380 	int tconst, real_bps;
381 
382 	if (bps == 0)
383 		return 0;
384 
385 #ifdef	DIAGNOSTIC
386 	if (cs->cs_brg_clk == 0)
387 		panic("zs_set_speed");
388 #endif
389 
390 	tconst = BPS_TO_TCONST(cs->cs_brg_clk, bps);
391 	if (tconst < 0)
392 		return EINVAL;
393 
394 	/* Convert back to make sure we can do it. */
395 	real_bps = TCONST_TO_BPS(cs->cs_brg_clk, tconst);
396 
397 	/* XXX - Allow some tolerance here? */
398 	if (real_bps != bps)
399 		return EINVAL;
400 
401 	cs->cs_preg[12] = tconst;
402 	cs->cs_preg[13] = tconst >> 8;
403 
404 	/* Caller will stuff the pending registers. */
405 	return 0;
406 }
407 
408 int
409 zs_set_modes(cs, cflag)
410 	struct zs_chanstate *cs;
411 	int cflag;	/* bits per second */
412 {
413 	int s;
414 
415 	/*
416 	 * Output hardware flow control on the chip is horrendous:
417 	 * if carrier detect drops, the receiver is disabled, and if
418 	 * CTS drops, the transmitter is stoped IN MID CHARACTER!
419 	 * Therefore, NEVER set the HFC bit, and instead use the
420 	 * status interrupt to detect CTS changes.
421 	 */
422 	s = splzs();
423 	cs->cs_rr0_pps = 0;
424 	if ((cflag & (CLOCAL | MDMBUF)) != 0) {
425 		cs->cs_rr0_dcd = 0;
426 		if ((cflag & MDMBUF) == 0)
427 			cs->cs_rr0_pps = ZSRR0_DCD;
428 	} else
429 		cs->cs_rr0_dcd = ZSRR0_DCD;
430 	if ((cflag & CRTSCTS) != 0) {
431 		cs->cs_wr5_dtr = ZSWR5_DTR;
432 		cs->cs_wr5_rts = ZSWR5_RTS;
433 		cs->cs_rr0_cts = ZSRR0_CTS;
434 	} else if ((cflag & MDMBUF) != 0) {
435 		cs->cs_wr5_dtr = 0;
436 		cs->cs_wr5_rts = ZSWR5_DTR;
437 		cs->cs_rr0_cts = ZSRR0_DCD;
438 	} else {
439 		cs->cs_wr5_dtr = ZSWR5_DTR | ZSWR5_RTS;
440 		cs->cs_wr5_rts = 0;
441 		cs->cs_rr0_cts = 0;
442 	}
443 	splx(s);
444 
445 	/* Caller will stuff the pending registers. */
446 	return 0;
447 }
448 
449 
450 /*
451  * Read or write the chip with suitable delays.
452  */
453 
454 u_char
455 zs_read_reg(cs, reg)
456 	struct zs_chanstate *cs;
457 	u_char reg;
458 {
459 	u_char val;
460 
461 	*cs->cs_reg_csr = reg;
462 	ZS_DELAY();
463 	val = *cs->cs_reg_csr;
464 	ZS_DELAY();
465 	return val;
466 }
467 
468 void
469 zs_write_reg(cs, reg, val)
470 	struct zs_chanstate *cs;
471 	u_char reg, val;
472 {
473 
474 	*cs->cs_reg_csr = reg;
475 	ZS_DELAY();
476 	*cs->cs_reg_csr = val;
477 	ZS_DELAY();
478 }
479 
480 u_char
481 zs_read_csr(cs)
482 	struct zs_chanstate *cs;
483 {
484 	u_char val;
485 
486 	val = *cs->cs_reg_csr;
487 	ZS_DELAY();
488 	return val;
489 }
490 
491 void
492 zs_write_csr(cs, val)
493 	struct zs_chanstate *cs;
494 	u_char val;
495 {
496 
497 	*cs->cs_reg_csr = val;
498 	ZS_DELAY();
499 }
500 
501 u_char
502 zs_read_data(cs)
503 	struct zs_chanstate *cs;
504 {
505 	u_char val;
506 
507 	val = *cs->cs_reg_data;
508 	ZS_DELAY();
509 	return val;
510 }
511 
512 void
513 zs_write_data(cs, val)
514 	struct zs_chanstate *cs;
515 	u_char val;
516 {
517 
518 	*cs->cs_reg_data = val;
519 	ZS_DELAY();
520 }
521 
522 void
523 zs_abort(cs)
524 	struct zs_chanstate *cs;
525 {
526 
527 #ifdef DDB
528 	Debugger();
529 #endif
530 }
531 
532 /*
533  * Polled input char.
534  */
535 int
536 zs_getc(arg)
537 	void *arg;
538 {
539 	struct zs_chanstate *cs = arg;
540 	int s, c, rr0;
541 
542 	s = splhigh();
543 	/* Wait for a character to arrive. */
544 	do {
545 		rr0 = *cs->cs_reg_csr;
546 		ZS_DELAY();
547 	} while ((rr0 & ZSRR0_RX_READY) == 0);
548 
549 	c = *cs->cs_reg_data;
550 	ZS_DELAY();
551 	splx(s);
552 
553 	return c;
554 }
555 
556 /*
557  * Polled output char.
558  */
559 void
560 zs_putc(arg, c)
561 	void *arg;
562 	int c;
563 {
564 	struct zs_chanstate *cs = arg;
565 	int s, rr0;
566 
567 	s = splhigh();
568 	/* Wait for transmitter to become ready. */
569 	do {
570 		rr0 = *cs->cs_reg_csr;
571 		ZS_DELAY();
572 	} while ((rr0 & ZSRR0_TX_READY) == 0);
573 
574 	*cs->cs_reg_data = c;
575 	ZS_DELAY();
576 	splx(s);
577 }
578 
579 /*****************************************************************/
580 
581 static void zscnprobe(struct consdev *);
582 static void zscninit(struct consdev *);
583 static int  zscngetc(dev_t);
584 static void zscnputc(dev_t, int);
585 
586 struct consdev consdev_zs = {
587 	zscnprobe,
588 	zscninit,
589 	zscngetc,
590 	zscnputc,
591 	nullcnpollc,
592 	NULL,
593 	NULL,
594 	NULL,
595 	NODEV,
596 	CN_DEAD
597 };
598 
599 static void
600 zscnprobe(cn)
601 	struct consdev *cn;
602 {
603 }
604 
605 static void
606 zscninit(cn)
607 	struct consdev *cn;
608 {
609 	struct zs_chanstate *cs;
610 
611 	extern const struct cdevsw zstty_cdevsw;
612 	extern int tty00_is_console;
613 	extern volatile u_char *sccport0a;
614 
615 	cn->cn_dev = makedev(cdevsw_lookup_major(&zstty_cdevsw), 0);
616 	if (tty00_is_console)
617 		cn->cn_pri = CN_REMOTE;
618 	else
619 		cn->cn_pri = CN_NORMAL;
620 
621 	zc_cons = (struct zschan *)sccport0a; /* XXX */
622 
623 	zs_conschan = cs = &zs_conschan_store;
624 
625 	/* Setup temporary chanstate. */
626 	cs->cs_reg_csr  = &zc_cons->zc_csr;
627 	cs->cs_reg_data = &zc_cons->zc_data;
628 
629 	/* Initialize the pending registers. */
630 	memcpy(cs->cs_preg, zs_init_reg, 16);
631 	cs->cs_preg[5] |= ZSWR5_DTR | ZSWR5_RTS;
632 
633 	cs->cs_preg[12] = BPS_TO_TCONST(pclk[systype] / 16, 9600); /* XXX */
634 	cs->cs_preg[13] = 0;
635 	cs->cs_defspeed = 9600;
636 
637 	/* Clear the master interrupt enable. */
638 	zs_write_reg(cs, 9, 0);
639 
640 	/* Reset the whole SCC chip. */
641 	zs_write_reg(cs, 9, ZSWR9_HARD_RESET);
642 
643 	/* Copy "pending" to "current" and H/W */
644 	zs_loadchannelregs(cs);
645 }
646 
647 static int
648 zscngetc(dev)
649 	dev_t dev;
650 {
651 
652 	return zs_getc((void *)zs_conschan);
653 }
654 
655 static void
656 zscnputc(dev, c)
657 	dev_t dev;
658 	int c;
659 {
660 
661 	zs_putc((void *)zs_conschan, c);
662 }
663