xref: /netbsd-src/sys/arch/sparc64/dev/zs.c (revision 82d56013d7b633d116a93943de88e08335357a7c)
1 /*	$NetBSD: zs.c,v 1.76 2021/04/24 23:36:49 thorpej 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  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 /*
33  * Zilog Z8530 Dual UART driver (machine-dependent part)
34  *
35  * Runs two serial lines per chip using slave drivers.
36  * Plain tty/async lines use the zs_async slave.
37  * Sun keyboard/mouse uses the zs_kbd/zs_ms slaves.
38  */
39 
40 #include <sys/cdefs.h>
41 __KERNEL_RCSID(0, "$NetBSD: zs.c,v 1.76 2021/04/24 23:36:49 thorpej Exp $");
42 
43 #include "opt_ddb.h"
44 #include "opt_kgdb.h"
45 
46 #include <sys/param.h>
47 #include <sys/systm.h>
48 #include <sys/conf.h>
49 #include <sys/device.h>
50 #include <sys/file.h>
51 #include <sys/ioctl.h>
52 #include <sys/kernel.h>
53 #include <sys/proc.h>
54 #include <sys/tty.h>
55 #include <sys/time.h>
56 #include <sys/syslog.h>
57 #include <sys/intr.h>
58 
59 #include <machine/autoconf.h>
60 #include <machine/openfirm.h>
61 #include <machine/cpu.h>
62 #include <machine/eeprom.h>
63 #include <machine/psl.h>
64 #include <machine/z8530var.h>
65 
66 #include <dev/cons.h>
67 #include <dev/ic/z8530reg.h>
68 #include <dev/sun/kbd_ms_ttyvar.h>
69 #include <ddb/db_output.h>
70 
71 #include <dev/sbus/sbusvar.h>
72 #include <sparc64/dev/fhcvar.h>
73 #include <sparc64/dev/cons.h>
74 
75 #include "ioconf.h"
76 #include "kbd.h"	/* NKBD */
77 #include "ms.h"		/* NMS */
78 #include "zs.h" 	/* NZS */
79 
80 /* Make life easier for the initialized arrays here. */
81 #if NZS < 3
82 #undef  NZS
83 #define NZS 3
84 #endif
85 
86 /*
87  * Some warts needed by z8530tty.c -
88  * The default parity REALLY needs to be the same as the PROM uses,
89  * or you can not see messages done with printf during boot-up...
90  */
91 int zs_def_cflag = (CREAD | CS8 | HUPCL);
92 
93 /*
94  * The Sun provides a 4.9152 MHz clock to the ZS chips.
95  */
96 #define PCLK	(9600 * 512)	/* PCLK pin input clock rate */
97 
98 #define	ZS_DELAY()
99 
100 /* The layout of this is hardware-dependent (padding, order). */
101 struct zschan {
102 	volatile uint8_t zc_csr;	/* ctrl,status, and indirect access */
103 	uint8_t		zc_xxx0;
104 	volatile uint8_t zc_data;	/* data */
105 	uint8_t		zc_xxx1;
106 };
107 struct zsdevice {
108 	/* Yes, they are backwards. */
109 	struct	zschan zs_chan_b;
110 	struct	zschan zs_chan_a;
111 };
112 
113 /* ZS channel used as the console device (if any) */
114 void *zs_conschan_get, *zs_conschan_put;
115 
116 /* Saved PROM mappings */
117 static struct zsdevice *zsaddr[NZS];
118 
119 static uint8_t zs_init_reg[16] = {
120 	0,	/* 0: CMD (reset, etc.) */
121 	0,	/* 1: No interrupts yet. */
122 	0,	/* 2: 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 | ZSWR9_NO_VECTOR,
130 	0,	/*10: Misc. TX/RX control bits */
131 	ZSWR11_TXCLK_BAUD | ZSWR11_RXCLK_BAUD,
132 	((PCLK/32)/9600)-2,	/*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 /* Console ops */
139 static int  zscngetc(dev_t);
140 static void zscnputc(dev_t, int);
141 static void zscnpollc(dev_t, int);
142 
143 struct consdev zs_consdev = {
144 	.cn_getc = zscngetc,
145 	.cn_putc = zscnputc,
146 	.cn_pollc = zscnpollc,
147 };
148 
149 
150 /****************************************************************
151  * Autoconfig
152  ****************************************************************/
153 
154 /* Definition of the driver for autoconfig. */
155 static int  zs_match_sbus(device_t, cfdata_t, void *);
156 static void zs_attach_sbus(device_t, device_t, void *);
157 
158 static int  zs_match_fhc(device_t, cfdata_t, void *);
159 static void zs_attach_fhc(device_t, device_t, void *);
160 
161 static void zs_attach(struct zsc_softc *, struct zsdevice *, int);
162 static int  zs_print(void *, const char *);
163 
164 CFATTACH_DECL_NEW(zs, sizeof(struct zsc_softc),
165     zs_match_sbus, zs_attach_sbus, NULL, NULL);
166 
167 CFATTACH_DECL_NEW(zs_fhc, sizeof(struct zsc_softc),
168     zs_match_fhc, zs_attach_fhc, NULL, NULL);
169 
170 /* Interrupt handlers. */
171 int zscheckintr(void *);
172 static int zshard(void *);
173 static void zssoft(void *);
174 
175 static int zs_get_speed(struct zs_chanstate *);
176 
177 /* Console device support */
178 static int zs_console_flags(int, int, int);
179 
180 /* Power management hooks */
181 int  zs_enable(struct zs_chanstate *);
182 void zs_disable(struct zs_chanstate *);
183 
184 /* from dev/ic/z8530tty.c */
185 struct tty *zstty_get_tty_from_dev(device_t);
186 
187 /*
188  * Is the zs chip present?
189  */
190 static int
191 zs_match_sbus(device_t parent, cfdata_t cf, void *aux)
192 {
193 	struct sbus_attach_args *sa = aux;
194 
195 	if (strcmp(cf->cf_name, sa->sa_name) != 0)
196 		return (0);
197 
198 	return (1);
199 }
200 
201 static int
202 zs_match_fhc(device_t parent, cfdata_t cf, void *aux)
203 {
204 	struct fhc_attach_args *fa = aux;
205 
206 	if (strcmp(cf->cf_name, fa->fa_name) != 0)
207 		return (0);
208 
209 	return (1);
210 }
211 
212 static void
213 zs_attach_sbus(device_t parent, device_t self, void *aux)
214 {
215 	struct zsc_softc *zsc = device_private(self);
216 	struct sbus_attach_args *sa = aux;
217 	bus_space_handle_t bh;
218 	int zs_unit;
219 
220 	zsc->zsc_dev = self;
221 	zs_unit = device_unit(self);
222 
223 	if (sa->sa_nintr == 0) {
224 		aprint_error(": no interrupt lines\n");
225 		return;
226 	}
227 
228 	/* Use the mapping setup by the Sun PROM if possible. */
229 	if (zsaddr[zs_unit] == NULL) {
230 		/* Only map registers once. */
231 		if (sa->sa_npromvaddrs) {
232 			/*
233 			 * We're converting from a 32-bit pointer to a 64-bit
234 			 * pointer.  Since the 32-bit entity is negative, but
235 			 * the kernel is still mapped into the lower 4GB
236 			 * range, this needs to be zero-extended.
237 			 *
238 			 * XXXXX If we map the kernel and devices into the
239 			 * high 4GB range, this needs to be changed to
240 			 * sign-extend the address.
241 			 */
242 			sparc_promaddr_to_handle(sa->sa_bustag,
243 				sa->sa_promvaddrs[0], &bh);
244 
245 		} else {
246 
247 			if (sbus_bus_map(sa->sa_bustag, sa->sa_slot,
248 					 sa->sa_offset,
249 					 sa->sa_size,
250 					 BUS_SPACE_MAP_LINEAR,
251 					 &bh) != 0) {
252 				aprint_error(": cannot map registers\n");
253 				return;
254 			}
255 		}
256 		zsaddr[zs_unit] = bus_space_vaddr(sa->sa_bustag, bh);
257 	}
258 	zsc->zsc_bustag = sa->sa_bustag;
259 	zsc->zsc_dmatag = sa->sa_dmatag;
260 	zsc->zsc_promunit = prom_getpropint(sa->sa_node, "slave", -2);
261 	zsc->zsc_node = sa->sa_node;
262 	aprint_normal("\n");
263 	zs_attach(zsc, zsaddr[zs_unit], sa->sa_pri);
264 }
265 
266 static void
267 zs_attach_fhc(device_t parent, device_t self, void *aux)
268 {
269 	struct zsc_softc *zsc = device_private(self);
270 	struct fhc_attach_args *fa = aux;
271 	bus_space_handle_t bh;
272 	int zs_unit;
273 
274 	zsc->zsc_dev = self;
275 	zs_unit = device_unit(self);
276 
277 	if (fa->fa_nreg < 1 && fa->fa_npromvaddrs < 1) {
278 		printf(": no registers\n");
279 		return;
280 	}
281 
282 	if (fa->fa_nintr == 0) {
283 		aprint_error(": no interrupt lines\n");
284 		return;
285 	}
286 
287 	/* Use the mapping setup by the Sun PROM if possible. */
288 	if (zsaddr[zs_unit] == NULL) {
289 		/* Only map registers once. */
290 		if (fa->fa_npromvaddrs) {
291 			/*
292 			 * We're converting from a 32-bit pointer to a 64-bit
293 			 * pointer.  Since the 32-bit entity is negative, but
294 			 * the kernel is still mapped into the lower 4GB
295 			 * range, this needs to be zero-extended.
296 			 *
297 			 * XXXXX If we map the kernel and devices into the
298 			 * high 4GB range, this needs to be changed to
299 			 * sign-extend the address.
300 			 */
301 			sparc_promaddr_to_handle(fa->fa_bustag,
302 				fa->fa_promvaddrs[0], &bh);
303 
304 		} else {
305 
306 			if (fhc_bus_map(fa->fa_bustag,
307 					fa->fa_reg[0].fbr_slot,
308 					fa->fa_reg[0].fbr_offset,
309 					fa->fa_reg[0].fbr_size,
310 					BUS_SPACE_MAP_LINEAR,
311 					&bh) != 0) {
312 				aprint_error(": cannot map registers\n");
313 				return;
314 			}
315 		}
316 		zsaddr[zs_unit] = bus_space_vaddr(fa->fa_bustag, bh);
317 	}
318 	zsc->zsc_bustag = fa->fa_bustag;
319 	zsc->zsc_dmatag = NULL;
320 	zsc->zsc_promunit = prom_getpropint(fa->fa_node, "slave", -2);
321 	zsc->zsc_node = fa->fa_node;
322 	aprint_normal("\n");
323 	zs_attach(zsc, zsaddr[zs_unit], fa->fa_intr[0]);
324 }
325 
326 /*
327  * Attach a found zs.
328  *
329  * USE ROM PROPERTIES port-a-ignore-cd AND port-b-ignore-cd FOR
330  * SOFT CARRIER, AND keyboard PROPERTY FOR KEYBOARD/MOUSE?
331  */
332 static void
333 zs_attach(struct zsc_softc *zsc, struct zsdevice *zsd, int pri)
334 {
335 	struct zsc_attach_args zsc_args;
336 	struct zs_chanstate *cs;
337 	int channel;
338 
339 	if (zsd == NULL) {
340 		aprint_error(": configuration incomplete\n");
341 		return;
342 	}
343 
344 	/*
345 	 * Initialize software state for each channel.
346 	 */
347 	for (channel = 0; channel < 2; channel++) {
348 		struct zschan *zc;
349 		device_t child;
350 
351 		zsc_args.channel = channel;
352 		cs = &zsc->zsc_cs_store[channel];
353 		zsc->zsc_cs[channel] = cs;
354 
355 		zs_lock_init(cs);
356 		cs->cs_channel = channel;
357 		cs->cs_private = NULL;
358 		cs->cs_ops = &zsops_null;
359 		cs->cs_brg_clk = PCLK / 16;
360 
361 		zc = (channel == 0) ? &zsd->zs_chan_a : &zsd->zs_chan_b;
362 
363 		zsc_args.consdev = NULL;
364 		zsc_args.hwflags = zs_console_flags(zsc->zsc_promunit,
365 						    zsc->zsc_node,
366 						    channel);
367 
368 		if (zsc_args.hwflags & ZS_HWFLAG_CONSOLE) {
369 			zsc_args.hwflags |= ZS_HWFLAG_USE_CONSDEV;
370 			zsc_args.consdev = &zs_consdev;
371 		}
372 
373 		if ((zsc_args.hwflags & ZS_HWFLAG_CONSOLE_INPUT) != 0) {
374 			zs_conschan_get = zc;
375 		}
376 		if ((zsc_args.hwflags & ZS_HWFLAG_CONSOLE_OUTPUT) != 0) {
377 			zs_conschan_put = zc;
378 		}
379 
380 		/* Children need to set cn_dev, etc */
381 		cs->cs_reg_csr  = &zc->zc_csr;
382 		cs->cs_reg_data = &zc->zc_data;
383 
384 		memcpy(cs->cs_creg, zs_init_reg, 16);
385 		memcpy(cs->cs_preg, zs_init_reg, 16);
386 
387 		/* XXX: Consult PROM properties for this?! */
388 		cs->cs_defspeed = zs_get_speed(cs);
389 		cs->cs_defcflag = zs_def_cflag;
390 
391 		/* Make these correspond to cs_defcflag (-crtscts) */
392 		cs->cs_rr0_dcd = ZSRR0_DCD;
393 		cs->cs_rr0_cts = 0;
394 		cs->cs_wr5_dtr = ZSWR5_DTR | ZSWR5_RTS;
395 		cs->cs_wr5_rts = 0;
396 
397 		/*
398 		 * Clear the master interrupt enable.
399 		 * The INTENA is common to both channels,
400 		 * so just do it on the A channel.
401 		 */
402 		if (channel == 0) {
403 			zs_write_reg(cs, 9, 0);
404 		}
405 
406 		/*
407 		 * Look for a child driver for this channel.
408 		 * The child attach will setup the hardware.
409 		 */
410 		child = config_found(zsc->zsc_dev, (void *)&zsc_args,
411 		    zs_print, CFARG_EOL);
412 		if (child == NULL) {
413 			/* No sub-driver.  Just reset it. */
414 			uint8_t reset = (channel == 0) ?
415 				ZSWR9_A_RESET : ZSWR9_B_RESET;
416 			zs_lock_chan(cs);
417 			zs_write_reg(cs,  9, reset);
418 			zs_unlock_chan(cs);
419 		}
420 #if (NKBD > 0) || (NMS > 0)
421 		/*
422 		 * If this was a zstty it has a keyboard
423 		 * property on it we need to attach the
424 		 * sunkbd and sunms line disciplines.
425 		 */
426 		if (child
427 		    && (device_is_a(child, "zstty"))
428 		    && (prom_getproplen(zsc->zsc_node, "keyboard") == 0)) {
429 			struct kbd_ms_tty_attach_args kma;
430 			struct tty *tp;
431 
432 			kma.kmta_tp = tp = zstty_get_tty_from_dev(child);
433 			kma.kmta_dev = tp->t_dev;
434 			kma.kmta_consdev = zsc_args.consdev;
435 
436 			/* Attach 'em if we got 'em. */
437 #if (NKBD > 0)
438 			if (channel == 0) {
439 				kma.kmta_name = "keyboard";
440 				config_found(child, (void *)&kma, NULL,
441 				    CFARG_EOL);
442 			}
443 #endif
444 #if (NMS > 0)
445 			if (channel == 1) {
446 				kma.kmta_name = "mouse";
447 				config_found(child, (void *)&kma, NULL,
448 				    CFARG_EOL);
449 			}
450 #endif
451 		}
452 #endif
453 	}
454 
455 	/*
456 	 * Now safe to install interrupt handlers.  Note the arguments
457 	 * to the interrupt handlers aren't used.  Note, we only do this
458 	 * once since both SCCs interrupt at the same level and vector.
459 	 */
460 	bus_intr_establish(zsc->zsc_bustag, pri, IPL_SERIAL, zshard, zsc);
461 	if (!(zsc->zsc_softintr = softint_establish(SOFTINT_SERIAL, zssoft, zsc)))
462 		panic("zsattach: could not establish soft interrupt");
463 
464 	evcnt_attach_dynamic(&zsc->zsc_intrcnt, EVCNT_TYPE_INTR, NULL,
465 	    device_xname(zsc->zsc_dev), "intr");
466 
467 
468 	/*
469 	 * Set the master interrupt enable and interrupt vector.
470 	 * (common to both channels, do it on A)
471 	 */
472 	cs = zsc->zsc_cs[0];
473 	zs_lock_chan(cs);
474 	/* interrupt vector */
475 	zs_write_reg(cs, 2, zs_init_reg[2]);
476 	/* master interrupt control (enable) */
477 	zs_write_reg(cs, 9, zs_init_reg[9]);
478 	zs_unlock_chan(cs);
479 }
480 
481 static int
482 zs_print(void *aux, const char *name)
483 {
484 	struct zsc_attach_args *args = aux;
485 
486 	if (name != NULL)
487 		aprint_normal("%s: ", name);
488 
489 	if (args->channel != -1)
490 		aprint_normal(" channel %d", args->channel);
491 
492 	return (UNCONF);
493 }
494 
495 static int
496 zshard(void *arg)
497 {
498 	struct zsc_softc *zsc = arg;
499 	int rr3, rval;
500 
501 	rval = 0;
502 	while ((rr3 = zsc_intr_hard(zsc))) {
503 		/* Count up the interrupts. */
504 		rval |= rr3;
505 		zsc->zsc_intrcnt.ev_count++;
506 	}
507 	if (((zsc->zsc_cs[0] && zsc->zsc_cs[0]->cs_softreq) ||
508 	     (zsc->zsc_cs[1] && zsc->zsc_cs[1]->cs_softreq)) &&
509 	    zsc->zsc_softintr) {
510 		softint_schedule(zsc->zsc_softintr);
511 	}
512 	return (rval);
513 }
514 
515 int
516 zscheckintr(void *arg)
517 {
518 	struct zsc_softc *zsc;
519 	int unit, rval;
520 
521 	rval = 0;
522 	for (unit = 0; unit < zs_cd.cd_ndevs; unit++) {
523 
524 		zsc = device_lookup_private(&zs_cd, unit);
525 		if (zsc == NULL)
526 			continue;
527 		rval = (zshard((void *)zsc) || rval);
528 	}
529 	return (rval);
530 }
531 
532 
533 /*
534  * We need this only for TTY_DEBUG purposes.
535  */
536 static void
537 zssoft(void *arg)
538 {
539 	struct zsc_softc *zsc = arg;
540 
541 #if 0 /* not yet */
542 	/* Make sure we call the tty layer with tty_lock held. */
543 	mutex_spin_enter(&tty_lock);
544 #endif
545 	(void)zsc_intr_soft(zsc);
546 #ifdef TTY_DEBUG
547 	{
548 		struct zstty_softc *zst0 = zsc->zsc_cs[0]->cs_private;
549 		struct zstty_softc *zst1 = zsc->zsc_cs[1]->cs_private;
550 		if (zst0->zst_overflows || zst1->zst_overflows ) {
551 			struct trapframe *frame = (struct trapframe *)arg;
552 
553 			printf("zs silo overflow from %p\n",
554 			       (long)frame->tf_pc);
555 		}
556 	}
557 #endif
558 #if 0 /* not yet */
559 	mutex_spin_exit(&tty_lock);
560 #endif
561 }
562 
563 
564 /*
565  * Compute the current baud rate given a ZS channel.
566  */
567 static int
568 zs_get_speed(struct zs_chanstate *cs)
569 {
570 	int tconst;
571 
572 	tconst = zs_read_reg(cs, 12);
573 	tconst |= zs_read_reg(cs, 13) << 8;
574 	return (TCONST_TO_BPS(cs->cs_brg_clk, tconst));
575 }
576 
577 /*
578  * MD functions for setting the baud rate and control modes.
579  */
580 int
581 zs_set_speed(struct zs_chanstate *cs, int bps /* bits per second */)
582 {
583 	int tconst, real_bps;
584 
585 	if (bps == 0)
586 		return (0);
587 
588 #ifdef	DIAGNOSTIC
589 	if (cs->cs_brg_clk == 0)
590 		panic("zs_set_speed");
591 #endif
592 
593 	tconst = BPS_TO_TCONST(cs->cs_brg_clk, bps);
594 	if (tconst < 0)
595 		return (EINVAL);
596 
597 	/* Convert back to make sure we can do it. */
598 	real_bps = TCONST_TO_BPS(cs->cs_brg_clk, tconst);
599 
600 	/* XXX - Allow some tolerance here? */
601 	if (real_bps != bps)
602 		return (EINVAL);
603 
604 	cs->cs_preg[12] = tconst;
605 	cs->cs_preg[13] = tconst >> 8;
606 
607 	/* Caller will stuff the pending registers. */
608 	return (0);
609 }
610 
611 int
612 zs_set_modes(struct zs_chanstate *cs, int cflag)
613 {
614 
615 	/*
616 	 * Output hardware flow control on the chip is horrendous:
617 	 * if carrier detect drops, the receiver is disabled, and if
618 	 * CTS drops, the transmitter is stoped IN MID CHARACTER!
619 	 * Therefore, NEVER set the HFC bit, and instead use the
620 	 * status interrupt to detect CTS changes.
621 	 */
622 	zs_lock_chan(cs);
623 	cs->cs_rr0_pps = 0;
624 	if ((cflag & (CLOCAL | MDMBUF)) != 0) {
625 		cs->cs_rr0_dcd = 0;
626 		if ((cflag & MDMBUF) == 0)
627 			cs->cs_rr0_pps = ZSRR0_DCD;
628 	} else
629 		cs->cs_rr0_dcd = ZSRR0_DCD;
630 	if ((cflag & CRTSCTS) != 0) {
631 		cs->cs_wr5_dtr = ZSWR5_DTR;
632 		cs->cs_wr5_rts = ZSWR5_RTS;
633 		cs->cs_rr0_cts = ZSRR0_CTS;
634 	} else if ((cflag & CDTRCTS) != 0) {
635 		cs->cs_wr5_dtr = 0;
636 		cs->cs_wr5_rts = ZSWR5_DTR;
637 		cs->cs_rr0_cts = ZSRR0_CTS;
638 	} else if ((cflag & MDMBUF) != 0) {
639 		cs->cs_wr5_dtr = 0;
640 		cs->cs_wr5_rts = ZSWR5_DTR;
641 		cs->cs_rr0_cts = ZSRR0_DCD;
642 	} else {
643 		cs->cs_wr5_dtr = ZSWR5_DTR | ZSWR5_RTS;
644 		cs->cs_wr5_rts = 0;
645 		cs->cs_rr0_cts = 0;
646 	}
647 	zs_unlock_chan(cs);
648 
649 	/* Caller will stuff the pending registers. */
650 	return (0);
651 }
652 
653 
654 /*
655  * Read or write the chip with suitable delays.
656  */
657 
658 u_char
659 zs_read_reg(struct zs_chanstate *cs, u_char reg)
660 {
661 	u_char val;
662 
663 	*cs->cs_reg_csr = reg;
664 	ZS_DELAY();
665 	val = *cs->cs_reg_csr;
666 	ZS_DELAY();
667 	return (val);
668 }
669 
670 void
671 zs_write_reg(struct zs_chanstate *cs, u_char reg, u_char val)
672 {
673 	*cs->cs_reg_csr = reg;
674 	ZS_DELAY();
675 	*cs->cs_reg_csr = val;
676 	ZS_DELAY();
677 }
678 
679 u_char
680 zs_read_csr(struct zs_chanstate *cs)
681 {
682 	u_char val;
683 
684 	val = *cs->cs_reg_csr;
685 	ZS_DELAY();
686 	return (val);
687 }
688 
689 void
690 zs_write_csr(struct zs_chanstate *cs, u_char val)
691 {
692 	*cs->cs_reg_csr = val;
693 	ZS_DELAY();
694 }
695 
696 u_char
697 zs_read_data(struct zs_chanstate *cs)
698 {
699 	u_char val;
700 
701 	val = *cs->cs_reg_data;
702 	ZS_DELAY();
703 	return (val);
704 }
705 
706 void
707 zs_write_data(struct zs_chanstate *cs, u_char val)
708 {
709 	*cs->cs_reg_data = val;
710 	ZS_DELAY();
711 }
712 
713 /****************************************************************
714  * Console support functions (Sun specific!)
715  * Note: this code is allowed to know about the layout of
716  * the chip registers, and uses that to keep things simple.
717  * XXX - I think I like the mvme167 code better. -gwr
718  ****************************************************************/
719 
720 extern void Debugger(void);
721 
722 /*
723  * Handle user request to enter kernel debugger.
724  */
725 void
726 zs_abort(struct zs_chanstate *cs)
727 {
728 	volatile struct zschan *zc = zs_conschan_get;
729 	int rr0;
730 
731 	/* Wait for end of break to avoid PROM abort. */
732 	/* XXX - Limit the wait? */
733 	do {
734 		rr0 = zc->zc_csr;
735 		ZS_DELAY();
736 	} while (rr0 & ZSRR0_BREAK);
737 
738 #if defined(KGDB)
739 	zskgdb(cs);
740 #elif defined(DDB)
741 	{
742 		extern int db_active;
743 
744 		if (!db_active)
745 			Debugger();
746 		else
747 			/* Debugger is probably hozed */
748 			callrom();
749 	}
750 #else
751 	printf("stopping on keyboard abort\n");
752 	callrom();
753 #endif
754 }
755 
756 
757 /*
758  * Polled input char.
759  */
760 int
761 zs_getc(void *arg)
762 {
763 	volatile struct zschan *zc = arg;
764 	int s, c, rr0;
765 
766 	s = splhigh();
767 	/* Wait for a character to arrive. */
768 	do {
769 		rr0 = zc->zc_csr;
770 		ZS_DELAY();
771 	} while ((rr0 & ZSRR0_RX_READY) == 0);
772 
773 	c = zc->zc_data;
774 	ZS_DELAY();
775 	splx(s);
776 
777 	/*
778 	 * This is used by the kd driver to read scan codes,
779 	 * so don't translate '\r' ==> '\n' here...
780 	 */
781 	return (c);
782 }
783 
784 /*
785  * Polled output char.
786  */
787 void
788 zs_putc(void *arg, int c)
789 {
790 	volatile struct zschan *zc = arg;
791 	int s, rr0;
792 
793 	s = splhigh();
794 
795 	/* Wait for transmitter to become ready. */
796 	do {
797 		rr0 = zc->zc_csr;
798 		ZS_DELAY();
799 	} while ((rr0 & ZSRR0_TX_READY) == 0);
800 
801 	/*
802 	 * Send the next character.
803 	 * Now you'd think that this could be followed by a ZS_DELAY()
804 	 * just like all the other chip accesses, but it turns out that
805 	 * the `transmit-ready' interrupt isn't de-asserted until
806 	 * some period of time after the register write completes
807 	 * (more than a couple instructions).  So to avoid stray
808 	 * interrupts we put in the 2us delay regardless of CPU model.
809 	 */
810 	zc->zc_data = c;
811 	delay(2);
812 
813 	splx(s);
814 }
815 
816 /*****************************************************************/
817 
818 
819 
820 
821 /*
822  * Polled console input putchar.
823  */
824 static int
825 zscngetc(dev_t dev)
826 {
827 	return (zs_getc(zs_conschan_get));
828 }
829 
830 /*
831  * Polled console output putchar.
832  */
833 static void
834 zscnputc(dev_t dev, int c)
835 {
836 	zs_putc(zs_conschan_put, c);
837 }
838 
839 int swallow_zsintrs;
840 
841 static void
842 zscnpollc(dev_t dev, int on)
843 {
844 	/*
845 	 * Need to tell zs driver to acknowledge all interrupts or we get
846 	 * annoying spurious interrupt messages.  This is because mucking
847 	 * with spl() levels during polling does not prevent interrupts from
848 	 * being generated.
849 	 */
850 
851 	if (on) swallow_zsintrs++;
852 	else swallow_zsintrs--;
853 }
854 
855 int
856 zs_console_flags(int promunit, int node, int channel)
857 {
858 	int cookie, flags = 0;
859 	char buf[255];
860 
861 	/*
862 	 * We'll just do the OBP grovelling down here since that's
863 	 * the only type of firmware we support.
864 	 */
865 
866 	/* Default to channel 0 if there are no explicit prom args */
867 	cookie = 0;
868 	if (node == prom_instance_to_package(prom_stdin())) {
869 		if (prom_getoption("input-device", buf, sizeof buf) == 0 &&
870 		    strcmp("ttyb", buf) == 0)
871 			cookie = 1;
872 
873 		if (channel == cookie)
874 			flags |= ZS_HWFLAG_CONSOLE_INPUT;
875 	}
876 
877 	if (node == prom_instance_to_package(prom_stdout())) {
878 		if (prom_getoption("output-device", buf, sizeof buf) == 0 &&
879 		    strcmp("ttyb", buf) == 0)
880 			cookie = 1;
881 
882 		if (channel == cookie)
883 			flags |= ZS_HWFLAG_CONSOLE_OUTPUT;
884 	}
885 
886 	return (flags);
887 }
888 
889