xref: /netbsd-src/sys/arch/mvme68k/dev/zs.c (revision e5548b402ae4c44fb816de42c7bba9581ce23ef5)
1 /*	$NetBSD: zs.c,v 1.34 2005/12/11 12:18:17 christos 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  * Modified for NetBSD/mvme68k by Jason R. Thorpe <thorpej@NetBSD.org>
46  */
47 
48 #include <sys/cdefs.h>
49 __KERNEL_RCSID(0, "$NetBSD: zs.c,v 1.34 2005/12/11 12:18:17 christos Exp $");
50 
51 #include <sys/param.h>
52 #include <sys/systm.h>
53 #include <sys/conf.h>
54 #include <sys/device.h>
55 #include <sys/file.h>
56 #include <sys/ioctl.h>
57 #include <sys/kernel.h>
58 #include <sys/proc.h>
59 #include <sys/tty.h>
60 #include <sys/time.h>
61 #include <sys/syslog.h>
62 
63 #include <dev/cons.h>
64 #include <dev/ic/z8530reg.h>
65 #include <machine/z8530var.h>
66 
67 #include <machine/cpu.h>
68 #include <machine/bus.h>
69 #include <machine/intr.h>
70 
71 #include <mvme68k/dev/zsvar.h>
72 
73 /*
74  * Some warts needed by z8530tty.c -
75  * The default parity REALLY needs to be the same as the PROM uses,
76  * or you can not see messages done with printf during boot-up...
77  */
78 int zs_def_cflag = (CREAD | CS8 | HUPCL);
79 
80 /* Flags from zscnprobe() */
81 static int zs_hwflags[NZSC][2];
82 
83 /* Default speed for each channel */
84 static int zs_defspeed[NZSC][2] = {
85 	{ 9600, 	/* port 1 */
86 	  9600 },	/* port 2 */
87 	{ 9600, 	/* port 3 */
88 	  9600 },	/* port 4 */
89 };
90 
91 static struct zs_chanstate zs_conschan_store;
92 static struct zs_chanstate *zs_conschan;
93 
94 u_char zs_init_reg[16] = {
95 	0,	/* 0: CMD (reset, etc.) */
96 	0,	/* 1: No interrupts yet. */
97 	0x18 + ZSHARD_PRI,	/* IVECT */
98 	ZSWR3_RX_8 | ZSWR3_RX_ENABLE,
99 	ZSWR4_CLK_X16 | ZSWR4_ONESB | ZSWR4_EVENP,
100 	ZSWR5_TX_8 | ZSWR5_TX_ENABLE,
101 	0,	/* 6: TXSYNC/SYNCLO */
102 	0,	/* 7: RXSYNC/SYNCHI */
103 	0,	/* 8: alias for data port */
104 	ZSWR9_MASTER_IE,
105 	0,	/*10: Misc. TX/RX control bits */
106 	ZSWR11_TXCLK_BAUD | ZSWR11_RXCLK_BAUD,
107 	0,			/*12: BAUDLO (default=9600) */
108 	0,			/*13: BAUDHI (default=9600) */
109 	ZSWR14_BAUD_ENA | ZSWR14_BAUD_FROM_PCLK,
110 	ZSWR15_BREAK_IE,
111 };
112 
113 
114 /****************************************************************
115  * Autoconfig
116  ****************************************************************/
117 
118 /* Definition of the driver for autoconfig. */
119 static int	zsc_print __P((void *, const char *name));
120 int	zs_getc __P((void *));
121 void	zs_putc __P((void *, int));
122 
123 #if 0
124 static int zs_get_speed __P((struct zs_chanstate *));
125 #endif
126 
127 extern struct cfdriver zsc_cd;
128 
129 cons_decl(zsc_pcc);
130 
131 
132 /*
133  * Configure children of an SCC.
134  */
135 void
136 zs_config(zsc, zs, vector, pclk)
137 	struct zsc_softc *zsc;
138 	struct zsdevice *zs;
139 	int vector, pclk;
140 {
141 	struct zsc_attach_args zsc_args;
142 	volatile struct zschan *zc;
143 	struct zs_chanstate *cs;
144 	int zsc_unit, channel, s;
145 
146 	zsc_unit = zsc->zsc_dev.dv_unit;
147 	printf(": Zilog 8530 SCC at vector 0x%x\n", vector);
148 
149 	/*
150 	 * Initialize software state for each channel.
151 	 */
152 	for (channel = 0; channel < 2; channel++) {
153 		zsc_args.channel = channel;
154 		zsc_args.hwflags = zs_hwflags[zsc_unit][channel];
155 		cs = &zsc->zsc_cs_store[channel];
156 		zsc->zsc_cs[channel] = cs;
157 		simple_lock_init(&cs->cs_lock);
158 
159 		/*
160 		 * If we're the console, copy the channel state, and
161 		 * adjust the console channel pointer.
162 		 */
163 		if (zsc_args.hwflags & ZS_HWFLAG_CONSOLE) {
164 			memcpy(cs, zs_conschan, sizeof(struct zs_chanstate));
165 			zs_conschan = cs;
166 		} else {
167 			zc = (channel == 0) ? &zs->zs_chan_a : &zs->zs_chan_b;
168 			cs->cs_reg_csr  = zc->zc_csr;
169 			cs->cs_reg_data = zc->zc_data;
170 			memcpy(cs->cs_creg, zs_init_reg, 16);
171 			memcpy(cs->cs_preg, zs_init_reg, 16);
172 			cs->cs_defspeed = zs_defspeed[zsc_unit][channel];
173 		}
174 
175 		cs->cs_brg_clk = pclk / 16;
176 		cs->cs_creg[2] = cs->cs_preg[2] = vector;
177 		zs_set_speed(cs, cs->cs_defspeed);
178 		cs->cs_creg[12] = cs->cs_preg[12];
179 		cs->cs_creg[13] = cs->cs_preg[13];
180 		cs->cs_defcflag = zs_def_cflag;
181 
182 		/* Make these correspond to cs_defcflag (-crtscts) */
183 		cs->cs_rr0_dcd = ZSRR0_DCD;
184 		cs->cs_rr0_cts = 0;
185 		cs->cs_wr5_dtr = ZSWR5_DTR | ZSWR5_RTS;
186 		cs->cs_wr5_rts = 0;
187 
188 		cs->cs_channel = channel;
189 		cs->cs_private = NULL;
190 		cs->cs_ops = &zsops_null;
191 
192 		/*
193 		 * Clear the master interrupt enable.
194 		 * The INTENA is common to both channels,
195 		 * so just do it on the A channel.
196 		 * Write the interrupt vector while we're at it.
197 		 */
198 		if (channel == 0) {
199 			zs_write_reg(cs, 9, 0);
200 			zs_write_reg(cs, 2, vector);
201 		}
202 
203 		/*
204 		 * Look for a child driver for this channel.
205 		 * The child attach will setup the hardware.
206 		 */
207 		if (!config_found(&zsc->zsc_dev, (void *)&zsc_args, zsc_print)) {
208 			/* No sub-driver.  Just reset it. */
209 			u_char reset = (channel == 0) ?
210 				ZSWR9_A_RESET : ZSWR9_B_RESET;
211 			s = splzs();
212 			zs_write_reg(cs,  9, reset);
213 			splx(s);
214 		}
215 	}
216 
217 	/*
218 	 * Allocate a software interrupt cookie.
219 	 */
220 	zsc->zsc_softintr_cookie = softintr_establish(IPL_SOFTSERIAL,
221 	    (void (*)(void *)) zsc_intr_soft, zsc);
222 #ifdef DEBUG
223 	assert(zsc->zsc_softintr_cookie);
224 #endif
225 }
226 
227 static int
228 zsc_print(aux, name)
229 	void *aux;
230 	const char *name;
231 {
232 	struct zsc_attach_args *args = aux;
233 
234 	if (name != NULL)
235 		aprint_normal("%s: ", name);
236 
237 	if (args->channel != -1)
238 		aprint_normal(" channel %d", args->channel);
239 
240 	return UNCONF;
241 }
242 
243 #if defined(MVME162) || defined(MVME172)
244 /*
245  * Our ZS chips each have their own interrupt vector.
246  */
247 int
248 zshard_unshared(arg)
249 	void *arg;
250 {
251 	struct zsc_softc *zsc = arg;
252 	int rval;
253 
254 	rval = zsc_intr_hard(zsc);
255 
256 	if (rval) {
257 		if ((zsc->zsc_cs[0]->cs_softreq) ||
258 		    (zsc->zsc_cs[1]->cs_softreq))
259 			softintr_schedule(zsc->zsc_softintr_cookie);
260 		zsc->zsc_evcnt.ev_count++;
261 	}
262 
263 	return (rval);
264 }
265 #endif
266 
267 #ifdef MVME147
268 /*
269  * Our ZS chips all share a common, PCC-vectored interrupt,
270  * so we have to look at all of them on each interrupt.
271  */
272 int
273 zshard_shared(arg)
274 	void *arg;
275 {
276 	struct zsc_softc *zsc;
277 	int unit, rval;
278 
279 	rval = 0;
280 	for (unit = 0; unit < zsc_cd.cd_ndevs; unit++) {
281 		zsc = zsc_cd.cd_devs[unit];
282 		if (zsc != NULL && zsc_intr_hard(zsc)) {
283 			if ((zsc->zsc_cs[0]->cs_softreq) ||
284 			    (zsc->zsc_cs[1]->cs_softreq))
285 				softintr_schedule(zsc->zsc_softintr_cookie);
286 			zsc->zsc_evcnt.ev_count++;
287 			rval++;
288 		}
289 	}
290 	return (rval);
291 }
292 #endif
293 
294 
295 #if 0
296 /*
297  * Compute the current baud rate given a ZSCC channel.
298  */
299 static int
300 zs_get_speed(cs)
301 	struct zs_chanstate *cs;
302 {
303 	int tconst;
304 
305 	tconst = zs_read_reg(cs, 12);
306 	tconst |= zs_read_reg(cs, 13) << 8;
307 	return (TCONST_TO_BPS(cs->cs_brg_clk, tconst));
308 }
309 #endif
310 
311 /*
312  * MD functions for setting the baud rate and control modes.
313  */
314 int
315 zs_set_speed(cs, bps)
316 	struct zs_chanstate *cs;
317 	int bps;	/* bits per second */
318 {
319 	int tconst, real_bps;
320 
321 	if (bps == 0)
322 		return (0);
323 
324 #ifdef	DIAGNOSTIC
325 	if (cs->cs_brg_clk == 0)
326 		panic("zs_set_speed");
327 #endif
328 
329 	tconst = BPS_TO_TCONST(cs->cs_brg_clk, bps);
330 	if (tconst < 0)
331 		return (EINVAL);
332 
333 	/* Convert back to make sure we can do it. */
334 	real_bps = TCONST_TO_BPS(cs->cs_brg_clk, tconst);
335 
336 	/* Allow 2% tolerance WRT the required bps */
337 	if (((abs(real_bps - bps) * 1000) / bps) > 20)
338 		return (EINVAL);
339 
340 	cs->cs_preg[12] = tconst;
341 	cs->cs_preg[13] = tconst >> 8;
342 
343 	/* Caller will stuff the pending registers. */
344 	return (0);
345 }
346 
347 int
348 zs_set_modes(cs, cflag)
349 	struct zs_chanstate *cs;
350 	int cflag;	/* bits per second */
351 {
352 	int s;
353 
354 	/*
355 	 * Output hardware flow control on the chip is horrendous:
356 	 * if carrier detect drops, the receiver is disabled, and if
357 	 * CTS drops, the transmitter is stoped IN MID CHARACTER!
358 	 * Therefore, NEVER set the HFC bit, and instead use the
359 	 * status interrupt to detect CTS changes.
360 	 */
361 	s = splzs();
362 	cs->cs_rr0_pps = 0;
363 	if ((cflag & (CLOCAL | MDMBUF)) != 0) {
364 		cs->cs_rr0_dcd = 0;
365 		if ((cflag & MDMBUF) == 0)
366 			cs->cs_rr0_pps = ZSRR0_DCD;
367 	} else
368 		cs->cs_rr0_dcd = ZSRR0_DCD;
369 	if ((cflag & CRTSCTS) != 0) {
370 		cs->cs_wr5_dtr = ZSWR5_DTR;
371 		cs->cs_wr5_rts = ZSWR5_RTS;
372 		cs->cs_rr0_cts = ZSRR0_CTS;
373 	} else if ((cflag & MDMBUF) != 0) {
374 		cs->cs_wr5_dtr = 0;
375 		cs->cs_wr5_rts = ZSWR5_DTR;
376 		cs->cs_rr0_cts = ZSRR0_DCD;
377 	} else {
378 		cs->cs_wr5_dtr = ZSWR5_DTR | ZSWR5_RTS;
379 		cs->cs_wr5_rts = 0;
380 		cs->cs_rr0_cts = 0;
381 	}
382 	splx(s);
383 
384 	/* Caller will stuff the pending registers. */
385 	return (0);
386 }
387 
388 
389 /*
390  * Read or write the chip with suitable delays.
391  */
392 
393 u_char
394 zs_read_reg(cs, reg)
395 	struct zs_chanstate *cs;
396 	u_char reg;
397 {
398 	u_char val;
399 
400 	*cs->cs_reg_csr = reg;
401 	ZS_DELAY();
402 	val = *cs->cs_reg_csr;
403 	ZS_DELAY();
404 	return val;
405 }
406 
407 void
408 zs_write_reg(cs, reg, val)
409 	struct zs_chanstate *cs;
410 	u_char reg, val;
411 {
412 	*cs->cs_reg_csr = reg;
413 	ZS_DELAY();
414 	*cs->cs_reg_csr = val;
415 	ZS_DELAY();
416 }
417 
418 u_char zs_read_csr(cs)
419 	struct zs_chanstate *cs;
420 {
421 	u_char val;
422 
423 	val = *cs->cs_reg_csr;
424 	ZS_DELAY();
425 	return val;
426 }
427 
428 void  zs_write_csr(cs, val)
429 	struct zs_chanstate *cs;
430 	u_char val;
431 {
432 	*cs->cs_reg_csr = val;
433 	ZS_DELAY();
434 }
435 
436 u_char zs_read_data(cs)
437 	struct zs_chanstate *cs;
438 {
439 	u_char val;
440 
441 	val = *cs->cs_reg_data;
442 	ZS_DELAY();
443 	return val;
444 }
445 
446 void  zs_write_data(cs, val)
447 	struct zs_chanstate *cs;
448 	u_char val;
449 {
450 	*cs->cs_reg_data = val;
451 	ZS_DELAY();
452 }
453 
454 /****************************************************************
455  * Console support functions (MVME specific!)
456  ****************************************************************/
457 
458 /*
459  * Polled input char.
460  */
461 int
462 zs_getc(arg)
463 	void *arg;
464 {
465 	struct zs_chanstate *cs = arg;
466 	int s, c, rr0, stat;
467 
468 	s = splhigh();
469  top:
470 	/* Wait for a character to arrive. */
471 	do {
472 		rr0 = *cs->cs_reg_csr;
473 		ZS_DELAY();
474 	} while ((rr0 & ZSRR0_RX_READY) == 0);
475 
476 	/* Read error register. */
477 	stat = zs_read_reg(cs, 1) & (ZSRR1_FE | ZSRR1_DO | ZSRR1_PE);
478 	if (stat) {
479 		zs_write_csr(cs, ZSM_RESET_ERR);
480 		goto top;
481 	}
482 
483 	/* Read character. */
484 	c = *cs->cs_reg_data;
485 	ZS_DELAY();
486 	splx(s);
487 
488 	return (c);
489 }
490 
491 /*
492  * Polled output char.
493  */
494 void
495 zs_putc(arg, c)
496 	void *arg;
497 	int c;
498 {
499 	struct zs_chanstate *cs = arg;
500 	int s, rr0;
501 
502 	s = splhigh();
503 	/* Wait for transmitter to become ready. */
504 	do {
505 		rr0 = *cs->cs_reg_csr;
506 		ZS_DELAY();
507 	} while ((rr0 & ZSRR0_TX_READY) == 0);
508 
509 	*cs->cs_reg_data = c;
510 	ZS_DELAY();
511 	splx(s);
512 }
513 
514 /*
515  * Common parts of console init.
516  */
517 void
518 zs_cnconfig(zsc_unit, channel, zs, pclk)
519 	int zsc_unit, channel;
520 	struct zsdevice *zs;
521 	int pclk;
522 {
523 	struct zs_chanstate *cs;
524 	struct zschan *zc;
525 
526 	zc = (channel == 0) ? &zs->zs_chan_a : &zs->zs_chan_b;
527 
528 	/*
529 	 * Pointer to channel state.  Later, the console channel
530 	 * state is copied into the softc, and the console channel
531 	 * pointer adjusted to point to the new copy.
532 	 */
533 	zs_conschan = cs = &zs_conschan_store;
534 	zs_hwflags[zsc_unit][channel] = ZS_HWFLAG_CONSOLE;
535 
536 	/* Setup temporary chanstate. */
537 	cs->cs_brg_clk = pclk / 16;
538 	cs->cs_reg_csr  = zc->zc_csr;
539 	cs->cs_reg_data = zc->zc_data;
540 
541 	/* Initialize the pending registers. */
542 	memcpy(cs->cs_preg, zs_init_reg, 16);
543 	cs->cs_preg[5] |= (ZSWR5_DTR | ZSWR5_RTS);
544 
545 #if 0
546 	/* XXX: Preserve BAUD rate from boot loader. */
547 	/* XXX: Also, why reset the chip here? -gwr */
548 	cs->cs_defspeed = zs_get_speed(cs);
549 #else
550 	cs->cs_defspeed = 9600;	/* XXX */
551 #endif
552 	zs_set_speed(cs, cs->cs_defspeed);
553 	cs->cs_creg[12] = cs->cs_preg[12];
554 	cs->cs_creg[13] = cs->cs_preg[13];
555 
556 	/* Clear the master interrupt enable. */
557 	zs_write_reg(cs, 9, 0);
558 
559 	/* Reset the whole SCC chip. */
560 	zs_write_reg(cs, 9, ZSWR9_HARD_RESET);
561 
562 	/* Copy "pending" to "current" and H/W. */
563 	zs_loadchannelregs(cs);
564 }
565 
566 /*
567  * Polled console input putchar.
568  */
569 int
570 zsc_pcccngetc(dev)
571 	dev_t dev;
572 {
573 	struct zs_chanstate *cs = zs_conschan;
574 	int c;
575 
576 	c = zs_getc(cs);
577 	return (c);
578 }
579 
580 /*
581  * Polled console output putchar.
582  */
583 void
584 zsc_pcccnputc(dev, c)
585 	dev_t dev;
586 	int c;
587 {
588 	struct zs_chanstate *cs = zs_conschan;
589 
590 	zs_putc(cs, c);
591 }
592 
593 /*
594  * Handle user request to enter kernel debugger.
595  */
596 void
597 zs_abort(cs)
598 	struct zs_chanstate *cs;
599 {
600 	int rr0;
601 
602 	/* Wait for end of break to avoid PROM abort. */
603 	/* XXX - Limit the wait? */
604 	do {
605 		rr0 = *cs->cs_reg_csr;
606 		ZS_DELAY();
607 	} while (rr0 & ZSRR0_BREAK);
608 
609 	mvme68k_abort("SERIAL LINE ABORT");
610 }
611