xref: /openbsd-src/sys/arch/macppc/dev/zs.c (revision 2b0358df1d88d06ef4139321dd05bd5e05d91eaf)
1 /*	$OpenBSD: zs.c,v 1.17 2008/08/19 07:59:19 kettenis Exp $	*/
2 /*	$NetBSD: zs.c,v 1.17 2001/06/19 13:42:15 wiz Exp $	*/
3 
4 /*
5  * Copyright (c) 1996, 1998 Bill Studenmund
6  * Copyright (c) 1995 Gordon W. Ross
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. The name of the author may not be used to endorse or promote products
18  *    derived from this software without specific prior written permission.
19  * 4. All advertising materials mentioning features or use of this software
20  *    must display the following acknowledgement:
21  *      This product includes software developed by Gordon Ross
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
24  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
25  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
26  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
27  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
28  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
29  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
30  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
31  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
32  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33  */
34 
35 /*
36  * Zilog Z8530 Dual UART driver (machine-dependent part)
37  *
38  * Runs two serial lines per chip using slave drivers.
39  * Plain tty/async lines use the zs_async slave.
40  * Sun keyboard/mouse uses the zs_kbd/zs_ms slaves.
41  * Other ports use their own mice & keyboard slaves.
42  *
43  * Credits & history:
44  *
45  * With NetBSD 1.1, port-mac68k started using a port of the port-sparc
46  * (port-sun3?) zs.c driver (which was in turn based on code in the
47  * Berkeley 4.4 Lite release). Bill Studenmund did the port, with
48  * help from Allen Briggs and Gordon Ross <gwr@netbsd.org>. Noud de
49  * Brouwer field-tested the driver at a local ISP.
50  *
51  * Bill Studenmund and Gordon Ross then ported the machine-independent
52  * z8530 driver to work with port-mac68k. NetBSD 1.2 contained an
53  * intermediate version (mac68k using a local, patched version of
54  * the m.i. drivers), with NetBSD 1.3 containing a full version.
55  */
56 
57 #include <sys/param.h>
58 #include <sys/systm.h>
59 #include <sys/proc.h>
60 #include <sys/device.h>
61 #include <sys/conf.h>
62 #include <sys/file.h>
63 #include <sys/ioctl.h>
64 #include <sys/tty.h>
65 #include <sys/time.h>
66 #include <sys/kernel.h>
67 #include <sys/syslog.h>
68 
69 #include <dev/cons.h>
70 #include <dev/ofw/openfirm.h>
71 #include <dev/ic/z8530reg.h>
72 
73 #include <machine/z8530var.h>
74 #include <machine/autoconf.h>
75 #include <machine/cpu.h>
76 
77 /* Are these in a header file anywhere? */
78 /* Booter flags interface */
79 #define ZSMAC_RAW	0x01
80 #define ZSMAC_LOCALTALK	0x02
81 
82 #include "zsc.h"	/* get the # of zs chips defined */
83 
84 /*
85  * Some warts needed by z8530tty.c -
86  */
87 int zs_def_cflag = (CREAD | CS8 | HUPCL);
88 
89 /*
90  * abort detection on console will now timeout after iterating on a loop
91  * the following # of times. Cheep hack. Also, abort detection is turned
92  * off after a timeout (i.e. maybe there's not a terminal hooked up).
93  */
94 #define ZSABORT_DELAY 3000000
95 
96 struct zsdevice {
97 	/* Yes, they are backwards. */
98 	struct	zschan zs_chan_b;
99 	struct	zschan zs_chan_a;
100 };
101 
102 /* Flags from cninit() */
103 static int zs_hwflags[NZSC][2];
104 /* Default speed for each channel */
105 static int zs_defspeed[NZSC][2] = {
106 	{ 38400,	/* tty00 */
107 	  38400 },	/* tty01 */
108 };
109 
110 /* console stuff */
111 void	*zs_conschan = 0;
112 #ifdef	ZS_CONSOLE_ABORT
113 int	zs_cons_canabort = 1;
114 #else
115 int	zs_cons_canabort = 0;
116 #endif /* ZS_CONSOLE_ABORT*/
117 
118 /* device to which the console is attached--if serial. */
119 /* Mac stuff */
120 
121 int zs_get_speed(struct zs_chanstate *);
122 
123 /*
124  * Even though zsparam will set up the clock multiples, etc., we
125  * still set them here as: 1) mice & keyboards don't use zsparam,
126  * and 2) the console stuff uses these defaults before device
127  * attach.
128  */
129 
130 static u_char zs_init_reg[16] = {
131 	0,	/* 0: CMD (reset, etc.) */
132 	ZSWR1_RIE | ZSWR1_TIE | ZSWR1_SIE, 	/* 1: No interrupts yet. ??? */
133 	0,	/* IVECT */
134 	ZSWR3_RX_8 | ZSWR3_RX_ENABLE,
135 	ZSWR4_CLK_X16 | ZSWR4_ONESB | ZSWR4_EVENP,
136 	ZSWR5_TX_8 | ZSWR5_TX_ENABLE,
137 	0,	/* 6: TXSYNC/SYNCLO */
138 	0,	/* 7: RXSYNC/SYNCHI */
139 	0,	/* 8: alias for data port */
140 	ZSWR9_MASTER_IE,
141 	0,	/*10: Misc. TX/RX control bits */
142 	ZSWR11_TXCLK_BAUD | ZSWR11_RXCLK_BAUD,
143 	((PCLK/32)/38400)-2,	/*12: BAUDLO (default=38400) */
144 	0,			/*13: BAUDHI (default=38400) */
145 	ZSWR14_BAUD_ENA,
146 	ZSWR15_BREAK_IE,
147 };
148 
149 /****************************************************************
150  * Autoconfig
151  ****************************************************************/
152 
153 struct cfdriver zsc_cd = {
154 	NULL, "zsc", DV_TTY
155 };
156 
157 /* Definition of the driver for autoconfig. */
158 int	zsc_match(struct device *, void *, void *);
159 void	zsc_attach(struct device *, struct device *, void *);
160 int	zsc_print(void *, const char *name);
161 
162 /* Power management hooks */
163 int  zs_enable (struct zs_chanstate *);
164 void zs_disable (struct zs_chanstate *);
165 
166 struct cfattach zsc_ca = {
167 	sizeof(struct zsc_softc), zsc_match, zsc_attach
168 };
169 
170 extern struct cfdriver zsc_cd;
171 
172 int zshard(void *);
173 int zssoft(void *);
174 #ifdef ZS_TXDMA
175 int zs_txdma_int(void *);
176 #endif
177 
178 void zscnprobe(struct consdev *);
179 void zscninit(struct consdev *);
180 int  zscngetc(dev_t);
181 void zscnputc(dev_t, int);
182 void zscnpollc(dev_t, int);
183 
184 /*
185  * Is the zs chip present?
186  */
187 int
188 zsc_match(struct device *parent, void *match, void *aux)
189 {
190 	struct confargs *ca = aux;
191 	struct cfdata *cf = match;
192 
193 	if (strcmp(ca->ca_name, "escc") != 0)
194 		return 0;
195 
196 	if (ca->ca_nreg < 8)
197 		return 0;
198 
199 	if (cf->cf_unit > 1)
200 		return 0;
201 
202 	return 1;
203 }
204 
205 /*
206  * Attach a found zs.
207  *
208  * Match slave number to zs unit number, so that misconfiguration will
209  * not set up the keyboard as ttya, etc.
210  */
211 void
212 zsc_attach(struct device *parent, struct device *self, void *aux)
213 {
214 	struct zsc_softc *zsc = (void *)self;
215 	struct confargs *ca = aux;
216 	struct zsc_attach_args zsc_args;
217 	volatile struct zschan *zc;
218 	struct xzs_chanstate *xcs;
219 	struct zs_chanstate *cs;
220 	struct zsdevice *zsd;
221 	int zsc_unit, channel;
222 	int s, theflags;
223 	int node, intr[3][3];
224 	u_int regs[16];
225 
226 	zsc_unit = zsc->zsc_dev.dv_unit;
227 
228 	zsd = mapiodev(ca->ca_baseaddr + ca->ca_reg[0], ca->ca_reg[1]);
229 	node = OF_child(ca->ca_node);	/* ch-a */
230 
231 	for (channel = 0; channel < 2; channel++) {
232 		if (OF_getprop(node, "AAPL,interrupts",
233 			       intr[channel], sizeof(intr[0])) == -1 &&
234 		    OF_getprop(node, "interrupts",
235 			       intr[channel], sizeof(intr[0])) == -1) {
236 			printf(": cannot find interrupt property\n");
237 			return;
238 		}
239 
240 		if (OF_getprop(node, "reg", regs, sizeof(regs)) < 24) {
241 			printf(": cannot find reg property\n");
242 			return;
243 		}
244 		regs[2] += ca->ca_baseaddr;
245 		regs[4] += ca->ca_baseaddr;
246 #ifdef ZS_TXDMA
247 		zsc->zsc_txdmareg[channel] = mapiodev(regs[2], regs[3]);
248 		zsc->zsc_txdmacmd[channel] =
249 			dbdma_alloc(sizeof(dbdma_command_t) * 3);
250 		memset(zsc->zsc_txdmacmd[channel], 0,
251 			sizeof(dbdma_command_t) * 3);
252 		dbdma_reset(zsc->zsc_txdmareg[channel]);
253 #endif
254 		node = OF_peer(node);	/* ch-b */
255 	}
256 
257 	printf(": irq %d,%d\n", intr[0][0], intr[1][0]);
258 
259 	/*
260 	 * Initialize software state for each channel.
261 	 */
262 	for (channel = 0; channel < 2; channel++) {
263 		zsc_args.channel = channel;
264 		zsc_args.hwflags = zs_hwflags[zsc_unit][channel];
265 		xcs = &zsc->xzsc_xcs_store[channel];
266 		cs  = &xcs->xzs_cs;
267 		zsc->zsc_cs[channel] = cs;
268 
269 		cs->cs_channel = channel;
270 		cs->cs_private = NULL;
271 		cs->cs_ops = &zsops_null;
272 
273 		zc = (channel == 0) ? &zsd->zs_chan_a : &zsd->zs_chan_b;
274 
275 		cs->cs_reg_csr  = &zc->zc_csr;
276 		cs->cs_reg_data = &zc->zc_data;
277 
278 		memcpy(cs->cs_creg, zs_init_reg, 16);
279 		memcpy(cs->cs_preg, zs_init_reg, 16);
280 
281 		/* Current BAUD rate generator clock. */
282 		/* RTxC is 230400*16, so use 230400 */
283 		cs->cs_brg_clk = PCLK / 16;
284 		if (zsc_args.hwflags & ZS_HWFLAG_CONSOLE)
285 			cs->cs_defspeed = zs_get_speed(cs);
286 		else
287 			cs->cs_defspeed =
288 			    zs_defspeed[zsc_unit][channel];
289 		cs->cs_defcflag = zs_def_cflag;
290 
291 		/* Make these correspond to cs_defcflag (-crtscts) */
292 		cs->cs_rr0_dcd = ZSRR0_DCD;
293 		cs->cs_rr0_cts = 0;
294 		cs->cs_wr5_dtr = ZSWR5_DTR;
295 		cs->cs_wr5_rts = 0;
296 
297 #ifdef __notyet__
298 		cs->cs_slave_type = ZS_SLAVE_NONE;
299 #endif
300 
301 		/* Define BAUD rate stuff. */
302 		xcs->cs_clocks[0].clk = PCLK;
303 		xcs->cs_clocks[0].flags = ZSC_RTXBRG | ZSC_RTXDIV;
304 		xcs->cs_clocks[1].flags =
305 			ZSC_RTXBRG | ZSC_RTXDIV | ZSC_VARIABLE | ZSC_EXTERN;
306 		xcs->cs_clocks[2].flags = ZSC_TRXDIV | ZSC_VARIABLE;
307 		xcs->cs_clock_count = 3;
308 		if (channel == 0) {
309 			theflags = 0; /*mac68k_machine.modem_flags;*/
310 			/*xcs->cs_clocks[1].clk = mac68k_machine.modem_dcd_clk;*/
311 			/*xcs->cs_clocks[2].clk = mac68k_machine.modem_cts_clk;*/
312 			xcs->cs_clocks[1].clk = 0;
313 			xcs->cs_clocks[2].clk = 0;
314 		} else {
315 			theflags = 0; /*mac68k_machine.print_flags;*/
316 			xcs->cs_clocks[1].flags = ZSC_VARIABLE;
317 			/*
318 			 * Yes, we aren't defining ANY clock source enables for the
319 			 * printer's DCD clock in. The hardware won't let us
320 			 * use it. But a clock will freak out the chip, so we
321 			 * let you set it, telling us to bar interrupts on the line.
322 			 */
323 			/*xcs->cs_clocks[1].clk = mac68k_machine.print_dcd_clk;*/
324 			/*xcs->cs_clocks[2].clk = mac68k_machine.print_cts_clk;*/
325 			xcs->cs_clocks[1].clk = 0;
326 			xcs->cs_clocks[2].clk = 0;
327 		}
328 		if (xcs->cs_clocks[1].clk)
329 			zsc_args.hwflags |= ZS_HWFLAG_NO_DCD;
330 		if (xcs->cs_clocks[2].clk)
331 			zsc_args.hwflags |= ZS_HWFLAG_NO_CTS;
332 
333 		/* Set defaults in our "extended" chanstate. */
334 		xcs->cs_csource = 0;
335 		xcs->cs_psource = 0;
336 		xcs->cs_cclk_flag = 0;  /* Nothing fancy by default */
337 		xcs->cs_pclk_flag = 0;
338 
339 		if (theflags & ZSMAC_RAW) {
340 			zsc_args.hwflags |= ZS_HWFLAG_RAW;
341 			printf(" (raw defaults)");
342 		}
343 
344 		/*
345 		 * XXX - This might be better done with a "stub" driver
346 		 * (to replace zstty) that ignores LocalTalk for now.
347 		 */
348 		if (theflags & ZSMAC_LOCALTALK) {
349 			printf(" shielding from LocalTalk");
350 			cs->cs_defspeed = 1;
351 			cs->cs_creg[ZSRR_BAUDLO] = cs->cs_preg[ZSRR_BAUDLO] = 0xff;
352 			cs->cs_creg[ZSRR_BAUDHI] = cs->cs_preg[ZSRR_BAUDHI] = 0xff;
353 			zs_write_reg(cs, ZSRR_BAUDLO, 0xff);
354 			zs_write_reg(cs, ZSRR_BAUDHI, 0xff);
355 			/*
356 			 * If we might have LocalTalk, then make sure we have the
357 			 * Baud rate low-enough to not do any damage.
358 			 */
359 		}
360 
361 		/*
362 		 * We used to disable chip interrupts here, but we now
363 		 * do that in zscnprobe, just in case MacOS left the chip on.
364 		 */
365 
366 		xcs->cs_chip = 0;
367 
368 		/* Stash away a copy of the final H/W flags. */
369 		xcs->cs_hwflags = zsc_args.hwflags;
370 
371 		/*
372 		 * Look for a child driver for this channel.
373 		 * The child attach will setup the hardware.
374 		 */
375 		if (!config_found(self, (void *)&zsc_args, zsc_print)) {
376 			/* No sub-driver.  Just reset it. */
377 			u_char reset = (channel == 0) ?
378 				ZSWR9_A_RESET : ZSWR9_B_RESET;
379 			s = splzs();
380 			zs_write_reg(cs, 9, reset);
381 			splx(s);
382 		}
383 	}
384 
385 	/* XXX - Now safe to install interrupt handlers. */
386 	mac_intr_establish(parent, intr[0][0], IST_LEVEL, IPL_TTY,
387 	    zshard, NULL, "zs0");
388 	mac_intr_establish(parent, intr[1][0], IST_LEVEL, IPL_TTY,
389 	    zshard, NULL, "zs1");
390 #ifdef ZS_TXDMA
391 	mac_intr_establish(parent, intr[0][1], IST_LEVEL, IPL_TTY,
392 	    zs_txdma_int, (void *)0, "zsdma0");
393 	mac_intr_establish(parent, intr[1][1], IST_LEVEL, IPL_TTY,
394 	    zs_txdma_int, (void *)1, "zsdma1");
395 #endif
396 
397 	/*
398 	 * Set the master interrupt enable and interrupt vector.
399 	 * (common to both channels, do it on A)
400 	 */
401 	cs = zsc->zsc_cs[0];
402 	s = splzs();
403 	/* interrupt vector */
404 	zs_write_reg(cs, 2, zs_init_reg[2]);
405 	/* master interrupt control (enable) */
406 	zs_write_reg(cs, 9, zs_init_reg[9]);
407 	splx(s);
408 
409 	/* connect power management for port 0 */
410 	cs->enable = zs_enable;
411 	cs->disable = zs_disable;
412 }
413 
414 int
415 zsc_print(void *aux, const char *name)
416 {
417 	struct zsc_attach_args *args = aux;
418 
419 	if (name != NULL)
420 		printf("%s: ", name);
421 
422 	if (args->channel != -1)
423 		printf(" channel %d", args->channel);
424 
425 	return UNCONF;
426 }
427 
428 int
429 zsmdioctl(struct zs_chanstate *cs, u_long cmd, caddr_t data)
430 {
431 	switch (cmd) {
432 	default:
433 		return (-1);
434 	}
435 	return (0);
436 }
437 
438 void
439 zsmd_setclock(struct zs_chanstate *cs)
440 {
441 #ifdef NOTYET
442 	struct xzs_chanstate *xcs = (void *)cs;
443 
444 	if (cs->cs_channel != 0)
445 		return;
446 
447 	/*
448 	 * If the new clock has the external bit set, then select the
449 	 * external source.
450 	 */
451 	via_set_modem((xcs->cs_pclk_flag & ZSC_EXTERN) ? 1 : 0);
452 #endif
453 }
454 
455 static int zssoftpending;
456 
457 /*
458  * Our ZS chips all share a common, autovectored interrupt,
459  * so we have to look at all of them on each interrupt.
460  */
461 int
462 zshard(void *arg)
463 {
464 	struct zsc_softc *zsc;
465 	int unit, rval;
466 
467 	rval = 0;
468 	for (unit = 0; unit < zsc_cd.cd_ndevs; unit++) {
469 		zsc = zsc_cd.cd_devs[unit];
470 		if (zsc == NULL)
471 			continue;
472 		rval |= zsc_intr_hard(zsc);
473 		if (zsc->zsc_cs[0]->cs_softreq)
474 		{
475 			/* zsc_req_softint(zsc); */
476 			/* We are at splzs here, so no need to lock. */
477 			if (zssoftpending == 0) {
478 				zssoftpending = 1;
479 				/* XXX setsoftserial(); */
480 				setsofttty(); /* UGLY HACK!!! */
481 			}
482 		}
483 	}
484 	return (rval);
485 }
486 
487 /*
488  * Similar scheme as for zshard (look at all of them)
489  */
490 int
491 zssoft(arg)
492 	void *arg;
493 {
494 	struct zsc_softc *zsc;
495 	int unit;
496 
497 	/* This is not the only ISR on this IPL. */
498 	if (zssoftpending == 0)
499 		return (0);
500 
501 	/*
502 	 * The soft intr. bit will be set by zshard only if
503 	 * the variable zssoftpending is zero.
504 	 */
505 	zssoftpending = 0;
506 
507 	for (unit = 0; unit < zsc_cd.cd_ndevs; ++unit) {
508 		zsc = zsc_cd.cd_devs[unit];
509 		if (zsc == NULL)
510 			continue;
511 		(void) zsc_intr_soft(zsc);
512 	}
513 	return (1);
514 }
515 
516 #ifdef ZS_TXDMA
517 int
518 zs_txdma_int(arg)
519 	void *arg;
520 {
521 	int ch = (int)arg;
522 	struct zsc_softc *zsc;
523 	struct zs_chanstate *cs;
524 	int unit = 0;			/* XXX */
525 	extern int zstty_txdma_int();
526 
527 	zsc = zsc_cd.cd_devs[unit];
528 	if (zsc == NULL)
529 		panic("zs_txdma_int");
530 
531 	cs = zsc->zsc_cs[ch];
532 	zstty_txdma_int(cs);
533 
534 	if (cs->cs_softreq) {
535 		if (zssoftpending == 0) {
536 			zssoftpending = 1;
537 			setsoftserial();
538 		}
539 	}
540 	return 1;
541 }
542 
543 void
544 zs_dma_setup(cs, pa, len)
545 	struct zs_chanstate *cs;
546 	caddr_t pa;
547 	int len;
548 {
549 	struct zsc_softc *zsc;
550 	dbdma_command_t *cmdp;
551 	int ch = cs->cs_channel;
552 
553 	zsc = zsc_cd.cd_devs[ch];
554 	cmdp = zsc->zsc_txdmacmd[ch];
555 
556 	DBDMA_BUILD(cmdp, DBDMA_CMD_OUT_LAST, 0, len, kvtop(pa),
557 		DBDMA_INT_ALWAYS, DBDMA_WAIT_NEVER, DBDMA_BRANCH_NEVER);
558 	cmdp++;
559 	DBDMA_BUILD(cmdp, DBDMA_CMD_STOP, 0, 0, 0,
560 		DBDMA_INT_NEVER, DBDMA_WAIT_NEVER, DBDMA_BRANCH_NEVER);
561 
562 	__asm __volatile("eieio");
563 
564 	dbdma_start(zsc->zsc_txdmareg[ch], zsc->zsc_txdmacmd[ch]);
565 }
566 #endif
567 
568 /*
569  * Compute the current baud rate given a ZS channel.
570  * XXX Assume internal BRG.
571  */
572 int
573 zs_get_speed(cs)
574 	struct zs_chanstate *cs;
575 {
576 	int tconst;
577 
578 	tconst = zs_read_reg(cs, 12);
579 	tconst |= zs_read_reg(cs, 13) << 8;
580 	return TCONST_TO_BPS(cs->cs_brg_clk, tconst);
581 }
582 
583 #ifndef ZS_TOLERANCE
584 #define ZS_TOLERANCE 51
585 /* 5% in tenths of a %, plus 1 so that exactly 5% will be ok. */
586 #endif
587 
588 /*
589  * Search through the signal sources in the channel, and
590  * pick the best one for the baud rate requested. Return
591  * a -1 if not achievable in tolerance. Otherwise return 0
592  * and fill in the values.
593  *
594  * This routine draws inspiration from the Atari port's zs.c
595  * driver in NetBSD 1.1 which did the same type of source switching.
596  * Tolerance code inspired by comspeed routine in isa/com.c.
597  *
598  * By Bill Studenmund, 1996-05-12
599  */
600 int
601 zs_set_speed(cs, bps)
602 	struct zs_chanstate *cs;
603 	int bps;	/* bits per second */
604 {
605 	struct xzs_chanstate *xcs = (void *)cs;
606 	int i, tc, tc0 = 0, tc1, s, sf = 0;
607 	int src, rate0, rate1, err, tol;
608 
609 	if (bps == 0)
610 		return (0);
611 
612 	src = -1;		/* no valid source yet */
613 	tol = ZS_TOLERANCE;
614 
615 	/*
616 	 * Step through all the sources and see which one matches
617 	 * the best. A source has to match BETTER than tol to be chosen.
618 	 * Thus if two sources give the same error, the first one will be
619 	 * chosen. Also, allow for the possability that one source might run
620 	 * both the BRG and the direct divider (i.e. RTxC).
621 	 */
622 	for (i = 0; i < xcs->cs_clock_count; i++) {
623 		if (xcs->cs_clocks[i].clk <= 0)
624 			continue;	/* skip non-existent or bad clocks */
625 		if (xcs->cs_clocks[i].flags & ZSC_BRG) {
626 			/* check out BRG at /16 */
627 			tc1 = BPS_TO_TCONST(xcs->cs_clocks[i].clk >> 4, bps);
628 			if (tc1 >= 0) {
629 				rate1 = TCONST_TO_BPS(xcs->cs_clocks[i].clk >> 4, tc1);
630 				err = abs(((rate1 - bps)*1000)/bps);
631 				if (err < tol) {
632 					tol = err;
633 					src = i;
634 					sf = xcs->cs_clocks[i].flags & ~ZSC_DIV;
635 					tc0 = tc1;
636 					rate0 = rate1;
637 				}
638 			}
639 		}
640 		if (xcs->cs_clocks[i].flags & ZSC_DIV) {
641 			/*
642 			 * Check out either /1, /16, /32, or /64
643 			 * Note: for /1, you'd better be using a synchronized
644 			 * clock!
645 			 */
646 			int b0 = xcs->cs_clocks[i].clk, e0 = abs(b0-bps);
647 			int b1 = b0 >> 4, e1 = abs(b1-bps);
648 			int b2 = b1 >> 1, e2 = abs(b2-bps);
649 			int b3 = b2 >> 1, e3 = abs(b3-bps);
650 
651 			if (e0 < e1 && e0 < e2 && e0 < e3) {
652 				err = e0;
653 				rate1 = b0;
654 				tc1 = ZSWR4_CLK_X1;
655 			} else if (e0 > e1 && e1 < e2  && e1 < e3) {
656 				err = e1;
657 				rate1 = b1;
658 				tc1 = ZSWR4_CLK_X16;
659 			} else if (e0 > e2 && e1 > e2 && e2 < e3) {
660 				err = e2;
661 				rate1 = b2;
662 				tc1 = ZSWR4_CLK_X32;
663 			} else {
664 				err = e3;
665 				rate1 = b3;
666 				tc1 = ZSWR4_CLK_X64;
667 			}
668 
669 			err = (err * 1000)/bps;
670 			if (err < tol) {
671 				tol = err;
672 				src = i;
673 				sf = xcs->cs_clocks[i].flags & ~ZSC_BRG;
674 				tc0 = tc1;
675 				rate0 = rate1;
676 			}
677 		}
678 	}
679 #ifdef ZSMACDEBUG
680 	printf("Checking for rate %d. Found source #%d.\n",bps, src);
681 #endif
682 	if (src == -1)
683 		return (EINVAL); /* no can do */
684 
685 	/*
686 	 * The M.I. layer likes to keep cs_brg_clk current, even though
687 	 * we are the only ones who should be touching the BRG's rate.
688 	 *
689 	 * Note: we are assuming that any ZSC_EXTERN signal source comes in
690 	 * on the RTxC pin. Correct for the mac68k obio zsc.
691 	 */
692 	if (sf & ZSC_EXTERN)
693 		cs->cs_brg_clk = xcs->cs_clocks[i].clk >> 4;
694 	else
695 		cs->cs_brg_clk = PCLK / 16;
696 
697 	/*
698 	 * Now we have a source, so set it up.
699 	 */
700 	s = splzs();
701 	xcs->cs_psource = src;
702 	xcs->cs_pclk_flag = sf;
703 	bps = rate0;
704 	if (sf & ZSC_BRG) {
705 		cs->cs_preg[4] = ZSWR4_CLK_X16;
706 		cs->cs_preg[11]= ZSWR11_RXCLK_BAUD | ZSWR11_TXCLK_BAUD;
707 		if (sf & ZSC_PCLK) {
708 			cs->cs_preg[14] = ZSWR14_BAUD_ENA | ZSWR14_BAUD_FROM_PCLK;
709 		} else {
710 			cs->cs_preg[14] = ZSWR14_BAUD_ENA;
711 		}
712 		tc = tc0;
713 	} else {
714 		cs->cs_preg[4] = tc0;
715 		if (sf & ZSC_RTXDIV) {
716 			cs->cs_preg[11] = ZSWR11_RXCLK_RTXC | ZSWR11_TXCLK_RTXC;
717 		} else {
718 			cs->cs_preg[11] = ZSWR11_RXCLK_TRXC | ZSWR11_TXCLK_TRXC;
719 		}
720 		cs->cs_preg[14]= 0;
721 		tc = 0xffff;
722 	}
723 	/* Set the BAUD rate divisor. */
724 	cs->cs_preg[12] = tc;
725 	cs->cs_preg[13] = tc >> 8;
726 	splx(s);
727 
728 #ifdef ZSMACDEBUG
729 	printf("Rate is %7d, tc is %7d, source no. %2d, flags %4x\n", \
730 	    bps, tc, src, sf);
731 	printf("Registers are: 4 %x, 11 %x, 14 %x\n\n",
732 		cs->cs_preg[4], cs->cs_preg[11], cs->cs_preg[14]);
733 #endif
734 
735 	cs->cs_preg[5] |= ZSWR5_RTS;	/* Make sure the drivers are on! */
736 
737 	/* Caller will stuff the pending registers. */
738 	return (0);
739 }
740 
741 int
742 zs_set_modes(cs, cflag)
743 	struct zs_chanstate *cs;
744 	int cflag;	/* bits per second */
745 {
746 	struct xzs_chanstate *xcs = (void*)cs;
747 	int s;
748 
749 	/*
750 	 * Make sure we don't enable hfc on a signal line we're ignoring.
751 	 * As we enable CTS interrupts only if we have CRTSCTS or CDTRCTS,
752 	 * this code also effectivly turns off ZSWR15_CTS_IE.
753 	 *
754 	 * Also, disable DCD interrupts if we've been told to ignore
755 	 * the DCD pin. Happens on mac68k because the input line for
756 	 * DCD can also be used as a clock input.  (Just set CLOCAL.)
757 	 *
758 	 * If someone tries to turn an invalid flow mode on, Just Say No
759 	 * (Suggested by gwr)
760 	 */
761 	if (xcs->cs_hwflags & ZS_HWFLAG_NO_DCD) {
762 		if (cflag & MDMBUF)
763 		printf(" opps\n");
764 		if (cflag & MDMBUF)
765 			return (EINVAL);
766 		cflag |= CLOCAL;
767 	}
768 #if 0
769 	if ((xcs->cs_hwflags & ZS_HWFLAG_NO_CTS) && (cflag & CRTSCTS))
770 		return (EINVAL);
771 #endif
772 
773 	/*
774 	 * Output hardware flow control on the chip is horrendous:
775 	 * if carrier detect drops, the receiver is disabled, and if
776 	 * CTS drops, the transmitter is stopped IN MID CHARACTER!
777 	 * Therefore, NEVER set the HFC bit, and instead use the
778 	 * status interrupt to detect CTS changes.
779 	 */
780 	s = splzs();
781 	if ((cflag & (CLOCAL | MDMBUF)) != 0)
782 		cs->cs_rr0_dcd = 0;
783 	else
784 		cs->cs_rr0_dcd = ZSRR0_DCD;
785 	/*
786 	 * The mac hardware only has one output, DTR (HSKo in Mac
787 	 * parlance). In HFC mode, we use it for the functions
788 	 * typically served by RTS and DTR on other ports, so we
789 	 * have to fake the upper layer out some.
790 	 *
791 	 * CRTSCTS we use CTS as an input which tells us when to shut up.
792 	 * We make no effort to shut up the other side of the connection.
793 	 * DTR is used to hang up the modem.
794 	 *
795 	 * In CDTRCTS, we use CTS to tell us to stop, but we use DTR to
796 	 * shut up the other side.
797 	 */
798 	if ((cflag & CRTSCTS) != 0) {
799 		cs->cs_wr5_dtr = ZSWR5_DTR;
800 		cs->cs_wr5_rts = 0;
801 		cs->cs_rr0_cts = ZSRR0_CTS;
802 #if 0
803 	} else if ((cflag & CDTRCTS) != 0) {
804 		cs->cs_wr5_dtr = 0;
805 		cs->cs_wr5_rts = ZSWR5_DTR;
806 		cs->cs_rr0_cts = ZSRR0_CTS;
807 #endif
808 	} else if ((cflag & MDMBUF) != 0) {
809 		cs->cs_wr5_dtr = 0;
810 		cs->cs_wr5_rts = ZSWR5_DTR;
811 		cs->cs_rr0_cts = ZSRR0_DCD;
812 	} else {
813 		cs->cs_wr5_dtr = ZSWR5_DTR;
814 		cs->cs_wr5_rts = 0;
815 		cs->cs_rr0_cts = 0;
816 	}
817 	splx(s);
818 
819 	/* Caller will stuff the pending registers. */
820 	return (0);
821 }
822 
823 
824 /*
825  * Read or write the chip with suitable delays.
826  * MacII hardware has the delay built in.
827  * No need for extra delay. :-) However, some clock-chirped
828  * macs, or zsc's on serial add-on boards might need it.
829  */
830 #define	ZS_DELAY()
831 
832 u_char
833 zs_read_reg(cs, reg)
834 	struct zs_chanstate *cs;
835 	u_char reg;
836 {
837 	u_char val;
838 
839 	out8(cs->cs_reg_csr, reg);
840 	ZS_DELAY();
841 	val = in8(cs->cs_reg_csr);
842 	ZS_DELAY();
843 	return val;
844 }
845 
846 void
847 zs_write_reg(cs, reg, val)
848 	struct zs_chanstate *cs;
849 	u_char reg, val;
850 {
851 	out8(cs->cs_reg_csr, reg);
852 	ZS_DELAY();
853 	out8(cs->cs_reg_csr, val);
854 	ZS_DELAY();
855 }
856 
857 u_char zs_read_csr(cs)
858 	struct zs_chanstate *cs;
859 {
860 	u_char val;
861 
862 	val = in8(cs->cs_reg_csr);
863 	ZS_DELAY();
864 	/* make up for the fact CTS is wired backwards */
865 	val ^= ZSRR0_CTS;
866 	return val;
867 }
868 
869 void  zs_write_csr(cs, val)
870 	struct zs_chanstate *cs;
871 	u_char val;
872 {
873 	/* Note, the csr does not write CTS... */
874 	out8(cs->cs_reg_csr, val);
875 	ZS_DELAY();
876 }
877 
878 u_char zs_read_data(cs)
879 	struct zs_chanstate *cs;
880 {
881 	u_char val;
882 
883 	val = in8(cs->cs_reg_data);
884 	ZS_DELAY();
885 	return val;
886 }
887 
888 void  zs_write_data(cs, val)
889 	struct zs_chanstate *cs;
890 	u_char val;
891 {
892 	out8(cs->cs_reg_data, val);
893 	ZS_DELAY();
894 }
895 
896 /*
897  * Power management hooks for zsopen() and zsclose().
898  * We use them to power on/off the ports, if necessary.
899  * This should be modified to turn on/off modem in PBG4, etc.
900  */
901 void macobio_modem_power(int enable);
902 int zs_enable(struct zs_chanstate *cs);
903 void zs_disable(struct zs_chanstate *cs);
904 
905 int
906 zs_enable(cs)
907 	struct zs_chanstate *cs;
908 {
909 	macobio_modem_power(1); /* Whee */
910 	cs->enabled = 1;
911 	return(0);
912 }
913 
914 void
915 zs_disable(cs)
916 	struct zs_chanstate *cs;
917 {
918 	macobio_modem_power(0); /* Whee */
919 	cs->enabled = 0;
920 }
921 
922 
923 /****************************************************************
924  * Console support functions (powermac specific!)
925  * Note: this code is allowed to know about the layout of
926  * the chip registers, and uses that to keep things simple.
927  * XXX - I think I like the mvme167 code better. -gwr
928  * XXX - Well :-P  :-)  -wrs
929  ****************************************************************/
930 
931 cons_decl(zs);
932 
933 void	zs_putc(volatile struct zschan *, int);
934 int	zs_getc(volatile struct zschan *);
935 extern int	zsopen( dev_t dev, int flags, int mode, struct proc *p);
936 
937 static int stdin, stdout;
938 
939 /*
940  * Console functions.
941  */
942 
943 /*
944  * zscnprobe is the routine which gets called as the kernel is trying to
945  * figure out where the console should be. Each io driver which might
946  * be the console (as defined in mac68k/conf.c) gets probed. The probe
947  * fills in the consdev structure. Important parts are the device #,
948  * and the console priority. Values are CN_DEAD (don't touch me),
949  * CN_LOWPRI (I'm here, but elsewhere might be better), CN_MIDPRI
950  * (the video, better than CN_LOWPRI), and CN_HIGHPRI (pick me!)
951  *
952  * As the mac's a bit different, we do extra work here. We mainly check
953  * to see if we have serial echo going on. Also chould check for default
954  * speeds.
955  */
956 
957 /*
958  * Polled input char.
959  */
960 int
961 zs_getc(zc)
962 	register volatile struct zschan *zc;
963 {
964 	register int s, c, rr0;
965 
966 	s = splhigh();
967 	/* Wait for a character to arrive. */
968 	do {
969 		rr0 = in8(&zc->zc_csr);
970 		ZS_DELAY();
971 	} while ((rr0 & ZSRR0_RX_READY) == 0);
972 
973 	c = in8(&zc->zc_data);
974 	ZS_DELAY();
975 	splx(s);
976 
977 	return (c);
978 }
979 
980 /*
981  * Polled output char.
982  */
983 void
984 zs_putc(zc, c)
985 	register volatile struct zschan *zc;
986 	int c;
987 {
988 	register int s, rr0;
989 	register long wait = 0;
990 
991 	s = splhigh();
992 	/* Wait for transmitter to become ready. */
993 	do {
994 		rr0 = in8(&zc->zc_csr);
995 		ZS_DELAY();
996 	} while (((rr0 & ZSRR0_TX_READY) == 0) && (wait++ < 1000000));
997 
998 	if ((rr0 & ZSRR0_TX_READY) != 0) {
999 		out8(&zc->zc_data, c);
1000 		ZS_DELAY();
1001 	}
1002 	splx(s);
1003 }
1004 
1005 
1006 /*
1007  * Polled console input putchar.
1008  */
1009 int
1010 zscngetc(dev)
1011 	dev_t dev;
1012 {
1013 	register volatile struct zschan *zc = zs_conschan;
1014 	register int c;
1015 
1016 	if (zc) {
1017 		c = zs_getc(zc);
1018 	} else {
1019 		char ch = 0;
1020 		OF_read(stdin, &ch, 1);
1021 		c = ch;
1022 	}
1023 	return c;
1024 }
1025 
1026 /*
1027  * Polled console output putchar.
1028  */
1029 void
1030 zscnputc(dev, c)
1031 	dev_t dev;
1032 	int c;
1033 {
1034 	register volatile struct zschan *zc = zs_conschan;
1035 
1036 	if (zc) {
1037 		zs_putc(zc, c);
1038 	} else {
1039 		char ch = c;
1040 		OF_write(stdout, &ch, 1);
1041 	}
1042 }
1043 
1044 void
1045 zscnprobe(cp)
1046 	struct consdev *cp;
1047 {
1048 	int chosen, pkg;
1049 	int unit = 0;
1050 	int maj;
1051 	char name[16];
1052 
1053 	if ((chosen = OF_finddevice("/chosen")) == -1)
1054 		return;
1055 
1056 	if (OF_getprop(chosen, "stdin", &stdin, sizeof(stdin)) == -1)
1057 		return;
1058 	if (OF_getprop(chosen, "stdout", &stdout, sizeof(stdout)) == -1)
1059 		return;
1060 
1061 	if ((pkg = OF_instance_to_package(stdin)) == -1)
1062 		return;
1063 
1064 	memset(name, 0, sizeof(name));
1065 	if (OF_getprop(pkg, "device_type", name, sizeof(name)) == -1)
1066 		return;
1067 
1068 	if (strcmp(name, "serial") != 0)
1069 		return;
1070 
1071 	memset(name, 0, sizeof(name));
1072 	if (OF_getprop(pkg, "name", name, sizeof(name)) == -1)
1073 		return;
1074 
1075 	if (strcmp(name, "ch-b") == 0)
1076 		unit = 1;
1077 
1078 	/* locate the major number */
1079 	for (maj = 0; maj < nchrdev; maj++)
1080 		if (cdevsw[maj].d_open == zsopen)
1081 			break;
1082 
1083 	cp->cn_dev = makedev(maj, unit);
1084 	cp->cn_pri = CN_HIGHPRI;
1085 }
1086 
1087 
1088 void
1089 zscninit(cp)
1090 	struct consdev *cp;
1091 {
1092 	int escc, escc_ch, obio;
1093 	unsigned int zs_offset, zs_size;
1094 	int ch = 0;
1095 	u_int32_t reg[5];
1096 	char name[16];
1097 
1098 	if ((escc_ch = OF_instance_to_package(stdin)) == -1)
1099 		return;
1100 
1101 	memset(name, 0, sizeof(name));
1102 	if (OF_getprop(escc_ch, "name", name, sizeof(name)) == -1)
1103 		return;
1104 
1105 	if (strcmp(name, "ch-b") == 0)
1106 		ch = 1;
1107 
1108 	if (OF_getprop(escc_ch, "reg", reg, sizeof(reg)) < 8)
1109 		return;
1110 	zs_offset = reg[0];
1111 	zs_size   = reg[1];
1112 
1113 	escc = OF_parent(escc_ch);
1114 	obio = OF_parent(escc);
1115 
1116 	if (OF_getprop(obio, "assigned-addresses", reg, sizeof(reg)) < 12)
1117 		return;
1118 	zs_conschan = mapiodev(reg[2] + zs_offset, zs_size);
1119 
1120 	zs_hwflags[0][ch] = ZS_HWFLAG_CONSOLE;
1121 }
1122 
1123 void
1124 zs_abort(struct zs_chanstate *channel)
1125 {
1126 	volatile struct zschan *zc = zs_conschan;
1127 	int rr0;
1128 
1129 	/* Wait for end of break to avoid PROM abort. */
1130 	/* XXX - Limit the wait? */
1131 	do {
1132 		rr0 = zc->zc_csr;
1133 		ZS_DELAY();
1134 	} while (rr0 & ZSRR0_BREAK);
1135 
1136 #if defined(DDB)
1137 	{
1138 		extern int db_active;
1139 
1140 		if (!db_active)
1141 			Debugger();
1142 	}
1143 #endif
1144 }
1145 
1146 /* copied from sparc - XXX? */
1147 void
1148 zscnpollc(dev, on)
1149         dev_t dev;
1150 	int on;
1151 {
1152 	/*
1153 	 * Need to tell zs driver to acknowledge all interrupts or we get
1154 	 * annoying spurious interrupt messages.  This is because mucking
1155 	 * with spl() levels during polling does not prevent interrupts from
1156 	 * being generated.
1157 	 */
1158 
1159 #if 0
1160 	if (on)
1161 		swallow_zsintrs++;
1162 	else
1163 		swallow_zsintrs--;
1164 #endif
1165 }
1166 
1167