xref: /netbsd-src/sys/arch/macppc/dev/zs.c (revision de1dfb1250df962f1ff3a011772cf58e605aed11)
1 /*	$NetBSD: zs.c,v 1.29 2004/03/24 19:42:04 matt Exp $	*/
2 
3 /*
4  * Copyright (c) 1996, 1998 Bill Studenmund
5  * Copyright (c) 1995 Gordon W. Ross
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
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  * 3. The name of the author may not be used to endorse or promote products
17  *    derived from this software without specific prior written permission.
18  * 4. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *      This product includes software developed by Gordon Ross
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
23  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
24  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
25  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
26  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
27  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
29  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
31  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 /*
35  * Zilog Z8530 Dual UART driver (machine-dependent part)
36  *
37  * Runs two serial lines per chip using slave drivers.
38  * Plain tty/async lines use the zs_async slave.
39  * Sun keyboard/mouse uses the zs_kbd/zs_ms slaves.
40  * Other ports use their own mice & keyboard slaves.
41  *
42  * Credits & history:
43  *
44  * With NetBSD 1.1, port-mac68k started using a port of the port-sparc
45  * (port-sun3?) zs.c driver (which was in turn based on code in the
46  * Berkeley 4.4 Lite release). Bill Studenmund did the port, with
47  * help from Allen Briggs and Gordon Ross <gwr@NetBSD.org>. Noud de
48  * Brouwer field-tested the driver at a local ISP.
49  *
50  * Bill Studenmund and Gordon Ross then ported the machine-independant
51  * z8530 driver to work with port-mac68k. NetBSD 1.2 contained an
52  * intermediate version (mac68k using a local, patched version of
53  * the m.i. drivers), with NetBSD 1.3 containing a full version.
54  */
55 
56 #include <sys/cdefs.h>
57 __KERNEL_RCSID(0, "$NetBSD: zs.c,v 1.29 2004/03/24 19:42:04 matt Exp $");
58 
59 #include "opt_ddb.h"
60 #include "opt_kgdb.h"
61 
62 #include <sys/param.h>
63 #include <sys/systm.h>
64 #include <sys/proc.h>
65 #include <sys/device.h>
66 #include <sys/conf.h>
67 #include <sys/file.h>
68 #include <sys/ioctl.h>
69 #include <sys/tty.h>
70 #include <sys/time.h>
71 #include <sys/kernel.h>
72 #include <sys/syslog.h>
73 #ifdef KGDB
74 #include <sys/kgdb.h>
75 #endif
76 
77 #include <dev/cons.h>
78 #include <dev/ofw/openfirm.h>
79 #include <dev/ic/z8530reg.h>
80 
81 #include <machine/z8530var.h>
82 #include <machine/autoconf.h>
83 #include <machine/cpu.h>
84 #include <machine/pio.h>
85 
86 /* Are these in a header file anywhere? */
87 /* Booter flags interface */
88 #define ZSMAC_RAW	0x01
89 #define ZSMAC_LOCALTALK	0x02
90 
91 #include "zsc.h"	/* get the # of zs chips defined */
92 
93 /*
94  * Some warts needed by z8530tty.c -
95  */
96 int zs_def_cflag = (CREAD | CS8 | HUPCL);
97 
98 /*
99  * abort detection on console will now timeout after iterating on a loop
100  * the following # of times. Cheep hack. Also, abort detection is turned
101  * off after a timeout (i.e. maybe there's not a terminal hooked up).
102  */
103 #define ZSABORT_DELAY 3000000
104 
105 struct zsdevice {
106 	/* Yes, they are backwards. */
107 	struct	zschan zs_chan_b;
108 	struct	zschan zs_chan_a;
109 };
110 
111 /* Flags from cninit() */
112 static int zs_hwflags[NZSC][2];
113 /* Default speed for each channel */
114 static int zs_defspeed[NZSC][2] = {
115 	{ 38400, 	/* tty00 */
116 	  38400 },	/* tty01 */
117 };
118 
119 /* console stuff */
120 void	*zs_conschan = 0;
121 #ifdef	ZS_CONSOLE_ABORT
122 int	zs_cons_canabort = 1;
123 #else
124 int	zs_cons_canabort = 0;
125 #endif /* ZS_CONSOLE_ABORT*/
126 
127 /* device to which the console is attached--if serial. */
128 /* Mac stuff */
129 
130 static int zs_get_speed __P((struct zs_chanstate *));
131 
132 /*
133  * Even though zsparam will set up the clock multiples, etc., we
134  * still set them here as: 1) mice & keyboards don't use zsparam,
135  * and 2) the console stuff uses these defaults before device
136  * attach.
137  */
138 
139 static u_char zs_init_reg[16] = {
140 	0,	/* 0: CMD (reset, etc.) */
141 	0,	/* 1: No interrupts yet. */
142 	0,	/* IVECT */
143 	ZSWR3_RX_8 | ZSWR3_RX_ENABLE,
144 	ZSWR4_CLK_X16 | ZSWR4_ONESB | ZSWR4_EVENP,
145 	ZSWR5_TX_8 | ZSWR5_TX_ENABLE,
146 	0,	/* 6: TXSYNC/SYNCLO */
147 	0,	/* 7: RXSYNC/SYNCHI */
148 	0,	/* 8: alias for data port */
149 	ZSWR9_MASTER_IE,
150 	0,	/*10: Misc. TX/RX control bits */
151 	ZSWR11_TXCLK_BAUD | ZSWR11_RXCLK_BAUD,
152 	((PCLK/32)/38400)-2,	/*12: BAUDLO (default=38400) */
153 	0,			/*13: BAUDHI (default=38400) */
154 	ZSWR14_BAUD_ENA,
155 	ZSWR15_BREAK_IE,
156 };
157 
158 /****************************************************************
159  * Autoconfig
160  ****************************************************************/
161 
162 /* Definition of the driver for autoconfig. */
163 static int	zsc_match __P((struct device *, struct cfdata *, void *));
164 static void	zsc_attach __P((struct device *, struct device *, void *));
165 static int  zsc_print __P((void *, const char *name));
166 
167 CFATTACH_DECL(zsc, sizeof(struct zsc_softc),
168     zsc_match, zsc_attach, NULL, NULL);
169 
170 extern struct cfdriver zsc_cd;
171 
172 int zshard __P((void *));
173 int zssoft __P((void *));
174 #ifdef ZS_TXDMA
175 static int zs_txdma_int __P((void *));
176 #endif
177 
178 void zscnprobe __P((struct consdev *));
179 void zscninit __P((struct consdev *));
180 int  zscngetc __P((dev_t));
181 void zscnputc __P((dev_t, int));
182 void zscnpollc __P((dev_t, int));
183 
184 /*
185  * Is the zs chip present?
186  */
187 static int
188 zsc_match(parent, cf, aux)
189 	struct device *parent;
190 	struct cfdata *cf;
191 	void *aux;
192 {
193 	struct confargs *ca = aux;
194 	int unit = cf->cf_unit;
195 
196 	if (strcmp(ca->ca_name, "escc") != 0)
197 		return 0;
198 
199 	if (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 static void
212 zsc_attach(parent, self, aux)
213 	struct device *parent;
214 	struct device *self;
215 	void *aux;
216 {
217 	struct zsc_softc *zsc = (void *)self;
218 	struct confargs *ca = aux;
219 	struct zsc_attach_args zsc_args;
220 	volatile struct zschan *zc;
221 	struct xzs_chanstate *xcs;
222 	struct zs_chanstate *cs;
223 	struct zsdevice *zsd;
224 	int zsc_unit, channel;
225 	int s, chip, theflags;
226 	int node, intr[2][3];
227 	u_int regs[6];
228 
229 	chip = 0;
230 	zsc_unit = zsc->zsc_dev.dv_unit;
231 
232 	ca->ca_reg[0] += ca->ca_baseaddr;
233 	zsd = mapiodev(ca->ca_reg[0], ca->ca_reg[1]);
234 
235 	node = OF_child(ca->ca_node);	/* ch-a */
236 
237 	for (channel = 0; channel < 2; channel++) {
238 		if (OF_getprop(node, "AAPL,interrupts",
239 			       intr[channel], sizeof(intr[0])) == -1 &&
240 		    OF_getprop(node, "interrupts",
241 			       intr[channel], sizeof(intr[0])) == -1) {
242 			printf(": cannot find interrupt property\n");
243 			return;
244 		}
245 
246 		if (OF_getprop(node, "reg", regs, sizeof(regs)) < 24) {
247 			printf(": cannot find reg property\n");
248 			return;
249 		}
250 		regs[2] += ca->ca_baseaddr;
251 		regs[4] += ca->ca_baseaddr;
252 #ifdef ZS_TXDMA
253 		zsc->zsc_txdmareg[channel] = mapiodev(regs[2], regs[3]);
254 		zsc->zsc_txdmacmd[channel] =
255 			dbdma_alloc(sizeof(dbdma_command_t) * 3);
256 		memset(zsc->zsc_txdmacmd[channel], 0,
257 			sizeof(dbdma_command_t) * 3);
258 		dbdma_reset(zsc->zsc_txdmareg[channel]);
259 #endif
260 		node = OF_peer(node);	/* ch-b */
261 	}
262 
263 	printf(": irq %d,%d\n", intr[0][0], intr[1][0]);
264 
265 	/*
266 	 * Initialize software state for each channel.
267 	 */
268 	for (channel = 0; channel < 2; channel++) {
269 		zsc_args.channel = channel;
270 		zsc_args.hwflags = zs_hwflags[zsc_unit][channel];
271 		xcs = &zsc->xzsc_xcs_store[channel];
272 		cs  = &xcs->xzs_cs;
273 		zsc->zsc_cs[channel] = cs;
274 
275 		simple_lock_init(&cs->cs_lock);
276 		cs->cs_channel = channel;
277 		cs->cs_private = NULL;
278 		cs->cs_ops = &zsops_null;
279 
280 		zc = (channel == 0) ? &zsd->zs_chan_a : &zsd->zs_chan_b;
281 
282 		cs->cs_reg_csr  = &zc->zc_csr;
283 		cs->cs_reg_data = &zc->zc_data;
284 
285 		memcpy(cs->cs_creg, zs_init_reg, 16);
286 		memcpy(cs->cs_preg, zs_init_reg, 16);
287 
288 		/* Current BAUD rate generator clock. */
289 		cs->cs_brg_clk = PCLK / 16;	/* RTxC is 230400*16, so use 230400 */
290 		if (zsc_args.hwflags & ZS_HWFLAG_CONSOLE)
291 			cs->cs_defspeed = zs_get_speed(cs);
292 		else
293 			cs->cs_defspeed = zs_defspeed[zsc_unit][channel];
294 		cs->cs_defcflag = zs_def_cflag;
295 
296 		/* Make these correspond to cs_defcflag (-crtscts) */
297 		cs->cs_rr0_dcd = ZSRR0_DCD;
298 		cs->cs_rr0_cts = 0;
299 		cs->cs_wr5_dtr = ZSWR5_DTR;
300 		cs->cs_wr5_rts = 0;
301 
302 #ifdef __notyet__
303 		cs->cs_slave_type = ZS_SLAVE_NONE;
304 #endif
305 
306 		/* Define BAUD rate stuff. */
307 		xcs->cs_clocks[0].clk = PCLK;
308 		xcs->cs_clocks[0].flags = ZSC_RTXBRG | ZSC_RTXDIV;
309 		xcs->cs_clocks[1].flags =
310 			ZSC_RTXBRG | ZSC_RTXDIV | ZSC_VARIABLE | ZSC_EXTERN;
311 		xcs->cs_clocks[2].flags = ZSC_TRXDIV | ZSC_VARIABLE;
312 		xcs->cs_clock_count = 3;
313 		if (channel == 0) {
314 			theflags = 0; /*mac68k_machine.modem_flags;*/
315 			/*xcs->cs_clocks[1].clk = mac68k_machine.modem_dcd_clk;*/
316 			/*xcs->cs_clocks[2].clk = mac68k_machine.modem_cts_clk;*/
317 			xcs->cs_clocks[1].clk = 0;
318 			xcs->cs_clocks[2].clk = 0;
319 		} else {
320 			theflags = 0; /*mac68k_machine.print_flags;*/
321 			xcs->cs_clocks[1].flags = ZSC_VARIABLE;
322 			/*
323 			 * Yes, we aren't defining ANY clock source enables for the
324 			 * printer's DCD clock in. The hardware won't let us
325 			 * use it. But a clock will freak out the chip, so we
326 			 * let you set it, telling us to bar interrupts on the line.
327 			 */
328 			/*xcs->cs_clocks[1].clk = mac68k_machine.print_dcd_clk;*/
329 			/*xcs->cs_clocks[2].clk = mac68k_machine.print_cts_clk;*/
330 			xcs->cs_clocks[1].clk = 0;
331 			xcs->cs_clocks[2].clk = 0;
332 		}
333 		if (xcs->cs_clocks[1].clk)
334 			zsc_args.hwflags |= ZS_HWFLAG_NO_DCD;
335 		if (xcs->cs_clocks[2].clk)
336 			zsc_args.hwflags |= ZS_HWFLAG_NO_CTS;
337 
338 		/* Set defaults in our "extended" chanstate. */
339 		xcs->cs_csource = 0;
340 		xcs->cs_psource = 0;
341 		xcs->cs_cclk_flag = 0;  /* Nothing fancy by default */
342 		xcs->cs_pclk_flag = 0;
343 
344 		if (theflags & ZSMAC_RAW) {
345 			zsc_args.hwflags |= ZS_HWFLAG_RAW;
346 			printf(" (raw defaults)");
347 		}
348 
349 		/*
350 		 * XXX - This might be better done with a "stub" driver
351 		 * (to replace zstty) that ignores LocalTalk for now.
352 		 */
353 		if (theflags & ZSMAC_LOCALTALK) {
354 			printf(" shielding from LocalTalk");
355 			cs->cs_defspeed = 1;
356 			cs->cs_creg[ZSRR_BAUDLO] = cs->cs_preg[ZSRR_BAUDLO] = 0xff;
357 			cs->cs_creg[ZSRR_BAUDHI] = cs->cs_preg[ZSRR_BAUDHI] = 0xff;
358 			zs_write_reg(cs, ZSRR_BAUDLO, 0xff);
359 			zs_write_reg(cs, ZSRR_BAUDHI, 0xff);
360 			/*
361 			 * If we might have LocalTalk, then make sure we have the
362 			 * Baud rate low-enough to not do any damage.
363 			 */
364 		}
365 
366 		/*
367 		 * We used to disable chip interrupts here, but we now
368 		 * do that in zscnprobe, just in case MacOS left the chip on.
369 		 */
370 
371 		xcs->cs_chip = chip;
372 
373 		/* Stash away a copy of the final H/W flags. */
374 		xcs->cs_hwflags = zsc_args.hwflags;
375 
376 		/*
377 		 * Look for a child driver for this channel.
378 		 * The child attach will setup the hardware.
379 		 */
380 		if (!config_found(self, (void *)&zsc_args, zsc_print)) {
381 			/* No sub-driver.  Just reset it. */
382 			u_char reset = (channel == 0) ?
383 				ZSWR9_A_RESET : ZSWR9_B_RESET;
384 			s = splzs();
385 			zs_write_reg(cs, 9, reset);
386 			splx(s);
387 		}
388 	}
389 
390 	/* XXX - Now safe to install interrupt handlers. */
391 	intr_establish(intr[0][0], IST_LEVEL, IPL_TTY, zshard, NULL);
392 	intr_establish(intr[1][0], IST_LEVEL, IPL_TTY, zshard, NULL);
393 #ifdef ZS_TXDMA
394 	intr_establish(intr[0][1], IST_LEVEL, IPL_TTY, zs_txdma_int, (void *)0);
395 	intr_establish(intr[1][1], IST_LEVEL, IPL_TTY, zs_txdma_int, (void *)1);
396 #endif
397 
398 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS
399 	zsc->zsc_si = softintr_establish(IPL_SOFTSERIAL,
400 		(void (*)(void *)) zsc_intr_soft, zsc);
401 #endif
402 
403 	/*
404 	 * Set the master interrupt enable and interrupt vector.
405 	 * (common to both channels, do it on A)
406 	 */
407 	cs = zsc->zsc_cs[0];
408 	s = splzs();
409 	/* interrupt vector */
410 	zs_write_reg(cs, 2, zs_init_reg[2]);
411 	/* master interrupt control (enable) */
412 	zs_write_reg(cs, 9, zs_init_reg[9]);
413 	splx(s);
414 }
415 
416 static int
417 zsc_print(aux, name)
418 	void *aux;
419 	const char *name;
420 {
421 	struct zsc_attach_args *args = aux;
422 
423 	if (name != NULL)
424 		aprint_normal("%s: ", name);
425 
426 	if (args->channel != -1)
427 		aprint_normal(" channel %d", args->channel);
428 
429 	return UNCONF;
430 }
431 
432 int
433 zsmdioctl(cs, cmd, data)
434 	struct zs_chanstate *cs;
435 	u_long cmd;
436 	caddr_t data;
437 {
438 	switch (cmd) {
439 	default:
440 		return (EPASSTHROUGH);
441 	}
442 	return (0);
443 }
444 
445 void
446 zsmd_setclock(cs)
447 	struct zs_chanstate *cs;
448 {
449 #ifdef NOTYET
450 	struct xzs_chanstate *xcs = (void *)cs;
451 
452 	if (cs->cs_channel != 0)
453 		return;
454 
455 	/*
456 	 * If the new clock has the external bit set, then select the
457 	 * external source.
458 	 */
459 	via_set_modem((xcs->cs_pclk_flag & ZSC_EXTERN) ? 1 : 0);
460 #endif
461 }
462 
463 #ifndef __HAVE_GENERIC_SOFT_INTERRUPTS
464 static int zssoftpending;
465 #endif
466 
467 /*
468  * Our ZS chips all share a common, autovectored interrupt,
469  * so we have to look at all of them on each interrupt.
470  */
471 int
472 zshard(arg)
473 	void *arg;
474 {
475 	register struct zsc_softc *zsc;
476 	register int unit, rval;
477 
478 	rval = 0;
479 	for (unit = 0; unit < zsc_cd.cd_ndevs; unit++) {
480 		zsc = zsc_cd.cd_devs[unit];
481 		if (zsc == NULL)
482 			continue;
483 		rval |= zsc_intr_hard(zsc);
484 		if ((zsc->zsc_cs[0]->cs_softreq) ||
485 			(zsc->zsc_cs[1]->cs_softreq))
486 		{
487 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS
488 			softintr_schedule(zsc->zsc_si);
489 #else
490 			/* zsc_req_softint(zsc); */
491 			/* We are at splzs here, so no need to lock. */
492 			if (zssoftpending == 0) {
493 				zssoftpending = 1;
494 				setsoftserial();
495 			}
496 #endif
497 		}
498 	}
499 	return (rval);
500 }
501 
502 #ifndef __HAVE_GENERIC_SOFT_INTERRUPTS
503 /*
504  * Similar scheme as for zshard (look at all of them)
505  */
506 int
507 zssoft(arg)
508 	void *arg;
509 {
510 	register struct zsc_softc *zsc;
511 	register int unit;
512 
513 	/* This is not the only ISR on this IPL. */
514 	if (zssoftpending == 0)
515 		return (0);
516 
517 	/*
518 	 * The soft intr. bit will be set by zshard only if
519 	 * the variable zssoftpending is zero.
520 	 */
521 	zssoftpending = 0;
522 
523 	for (unit = 0; unit < zsc_cd.cd_ndevs; ++unit) {
524 		zsc = zsc_cd.cd_devs[unit];
525 		if (zsc == NULL)
526 			continue;
527 		(void) zsc_intr_soft(zsc);
528 	}
529 	return (1);
530 }
531 #endif
532 
533 #ifdef ZS_TXDMA
534 int
535 zs_txdma_int(arg)
536 	void *arg;
537 {
538 	int ch = (int)arg;
539 	struct zsc_softc *zsc;
540 	struct zs_chanstate *cs;
541 	int unit = 0;			/* XXX */
542 
543 	zsc = zsc_cd.cd_devs[unit];
544 	if (zsc == NULL)
545 		panic("zs_txdma_int");
546 
547 	cs = zsc->zsc_cs[ch];
548 	zstty_txdma_int(cs);
549 
550 	if (cs->cs_softreq) {
551 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS
552 		softintr_schedule(zsc->zsc_si);
553 #else
554 		if (zssoftpending == 0) {
555 			zssoftpending = 1;
556 			setsoftserial();
557 		}
558 #endif
559 	}
560 	return 1;
561 }
562 
563 void
564 zs_dma_setup(cs, pa, len)
565 	struct zs_chanstate *cs;
566 	caddr_t pa;
567 	int len;
568 {
569 	struct zsc_softc *zsc;
570 	dbdma_command_t *cmdp;
571 	int ch = cs->cs_channel;
572 
573 	zsc = zsc_cd.cd_devs[ch];
574 	cmdp = zsc->zsc_txdmacmd[ch];
575 
576 	DBDMA_BUILD(cmdp, DBDMA_CMD_OUT_LAST, 0, len, kvtop(pa),
577 		DBDMA_INT_ALWAYS, DBDMA_WAIT_NEVER, DBDMA_BRANCH_NEVER);
578 	cmdp++;
579 	DBDMA_BUILD(cmdp, DBDMA_CMD_STOP, 0, 0, 0,
580 		DBDMA_INT_NEVER, DBDMA_WAIT_NEVER, DBDMA_BRANCH_NEVER);
581 
582 	__asm __volatile("eieio");
583 
584 	dbdma_start(zsc->zsc_txdmareg[ch], zsc->zsc_txdmacmd[ch]);
585 }
586 #endif
587 
588 /*
589  * Compute the current baud rate given a ZS channel.
590  * XXX Assume internal BRG.
591  */
592 int
593 zs_get_speed(cs)
594 	struct zs_chanstate *cs;
595 {
596 	int tconst;
597 
598 	tconst = zs_read_reg(cs, 12);
599 	tconst |= zs_read_reg(cs, 13) << 8;
600 	return TCONST_TO_BPS(cs->cs_brg_clk, tconst);
601 }
602 
603 #ifndef ZS_TOLERANCE
604 #define ZS_TOLERANCE 51
605 /* 5% in tenths of a %, plus 1 so that exactly 5% will be ok. */
606 #endif
607 
608 /*
609  * Search through the signal sources in the channel, and
610  * pick the best one for the baud rate requested. Return
611  * a -1 if not achievable in tolerance. Otherwise return 0
612  * and fill in the values.
613  *
614  * This routine draws inspiration from the Atari port's zs.c
615  * driver in NetBSD 1.1 which did the same type of source switching.
616  * Tolerance code inspired by comspeed routine in isa/com.c.
617  *
618  * By Bill Studenmund, 1996-05-12
619  */
620 int
621 zs_set_speed(cs, bps)
622 	struct zs_chanstate *cs;
623 	int bps;	/* bits per second */
624 {
625 	struct xzs_chanstate *xcs = (void *) cs;
626 	int i, tc, tc0 = 0, tc1, s, sf = 0;
627 	int src, rate0, rate1, err, tol;
628 
629 	if (bps == 0)
630 		return (0);
631 
632 	src = -1;		/* no valid source yet */
633 	tol = ZS_TOLERANCE;
634 
635 	/*
636 	 * Step through all the sources and see which one matches
637 	 * the best. A source has to match BETTER than tol to be chosen.
638 	 * Thus if two sources give the same error, the first one will be
639 	 * chosen. Also, allow for the possability that one source might run
640 	 * both the BRG and the direct divider (i.e. RTxC).
641 	 */
642 	for (i = 0; i < xcs->cs_clock_count; i++) {
643 		if (xcs->cs_clocks[i].clk <= 0)
644 			continue;	/* skip non-existent or bad clocks */
645 		if (xcs->cs_clocks[i].flags & ZSC_BRG) {
646 			/* check out BRG at /16 */
647 			tc1 = BPS_TO_TCONST(xcs->cs_clocks[i].clk >> 4, bps);
648 			if (tc1 >= 0) {
649 				rate1 = TCONST_TO_BPS(xcs->cs_clocks[i].clk >> 4, tc1);
650 				err = abs(((rate1 - bps)*1000)/bps);
651 				if (err < tol) {
652 					tol = err;
653 					src = i;
654 					sf = xcs->cs_clocks[i].flags & ~ZSC_DIV;
655 					tc0 = tc1;
656 					rate0 = rate1;
657 				}
658 			}
659 		}
660 		if (xcs->cs_clocks[i].flags & ZSC_DIV) {
661 			/*
662 			 * Check out either /1, /16, /32, or /64
663 			 * Note: for /1, you'd better be using a synchronized
664 			 * clock!
665 			 */
666 			int b0 = xcs->cs_clocks[i].clk, e0 = abs(b0-bps);
667 			int b1 = b0 >> 4, e1 = abs(b1-bps);
668 			int b2 = b1 >> 1, e2 = abs(b2-bps);
669 			int b3 = b2 >> 1, e3 = abs(b3-bps);
670 
671 			if (e0 < e1 && e0 < e2 && e0 < e3) {
672 				err = e0;
673 				rate1 = b0;
674 				tc1 = ZSWR4_CLK_X1;
675 			} else if (e0 > e1 && e1 < e2  && e1 < e3) {
676 				err = e1;
677 				rate1 = b1;
678 				tc1 = ZSWR4_CLK_X16;
679 			} else if (e0 > e2 && e1 > e2 && e2 < e3) {
680 				err = e2;
681 				rate1 = b2;
682 				tc1 = ZSWR4_CLK_X32;
683 			} else {
684 				err = e3;
685 				rate1 = b3;
686 				tc1 = ZSWR4_CLK_X64;
687 			}
688 
689 			err = (err * 1000)/bps;
690 			if (err < tol) {
691 				tol = err;
692 				src = i;
693 				sf = xcs->cs_clocks[i].flags & ~ZSC_BRG;
694 				tc0 = tc1;
695 				rate0 = rate1;
696 			}
697 		}
698 	}
699 #ifdef ZSMACDEBUG
700 	zsprintf("Checking for rate %d. Found source #%d.\n",bps, src);
701 #endif
702 	if (src == -1)
703 		return (EINVAL); /* no can do */
704 
705 	/*
706 	 * The M.I. layer likes to keep cs_brg_clk current, even though
707 	 * we are the only ones who should be touching the BRG's rate.
708 	 *
709 	 * Note: we are assuming that any ZSC_EXTERN signal source comes in
710 	 * on the RTxC pin. Correct for the mac68k obio zsc.
711 	 */
712 	if (sf & ZSC_EXTERN)
713 		cs->cs_brg_clk = xcs->cs_clocks[i].clk >> 4;
714 	else
715 		cs->cs_brg_clk = PCLK / 16;
716 
717 	/*
718 	 * Now we have a source, so set it up.
719 	 */
720 	s = splzs();
721 	xcs->cs_psource = src;
722 	xcs->cs_pclk_flag = sf;
723 	bps = rate0;
724 	if (sf & ZSC_BRG) {
725 		cs->cs_preg[4] = ZSWR4_CLK_X16;
726 		cs->cs_preg[11]= ZSWR11_RXCLK_BAUD | ZSWR11_TXCLK_BAUD;
727 		if (sf & ZSC_PCLK) {
728 			cs->cs_preg[14] = ZSWR14_BAUD_ENA | ZSWR14_BAUD_FROM_PCLK;
729 		} else {
730 			cs->cs_preg[14] = ZSWR14_BAUD_ENA;
731 		}
732 		tc = tc0;
733 	} else {
734 		cs->cs_preg[4] = tc0;
735 		if (sf & ZSC_RTXDIV) {
736 			cs->cs_preg[11] = ZSWR11_RXCLK_RTXC | ZSWR11_TXCLK_RTXC;
737 		} else {
738 			cs->cs_preg[11] = ZSWR11_RXCLK_TRXC | ZSWR11_TXCLK_TRXC;
739 		}
740 		cs->cs_preg[14]= 0;
741 		tc = 0xffff;
742 	}
743 	/* Set the BAUD rate divisor. */
744 	cs->cs_preg[12] = tc;
745 	cs->cs_preg[13] = tc >> 8;
746 	splx(s);
747 
748 #ifdef ZSMACDEBUG
749 	zsprintf("Rate is %7d, tc is %7d, source no. %2d, flags %4x\n", \
750 	    bps, tc, src, sf);
751 	zsprintf("Registers are: 4 %x, 11 %x, 14 %x\n\n",
752 		cs->cs_preg[4], cs->cs_preg[11], cs->cs_preg[14]);
753 #endif
754 
755 	cs->cs_preg[5] |= ZSWR5_RTS;	/* Make sure the drivers are on! */
756 
757 	/* Caller will stuff the pending registers. */
758 	return (0);
759 }
760 
761 int
762 zs_set_modes(cs, cflag)
763 	struct zs_chanstate *cs;
764 	int cflag;	/* bits per second */
765 {
766 	struct xzs_chanstate *xcs = (void*)cs;
767 	int s;
768 
769 	/*
770 	 * Make sure we don't enable hfc on a signal line we're ignoring.
771 	 * As we enable CTS interrupts only if we have CRTSCTS or CDTRCTS,
772 	 * this code also effectivly turns off ZSWR15_CTS_IE.
773 	 *
774 	 * Also, disable DCD interrupts if we've been told to ignore
775 	 * the DCD pin. Happens on mac68k because the input line for
776 	 * DCD can also be used as a clock input.  (Just set CLOCAL.)
777 	 *
778 	 * If someone tries to turn an invalid flow mode on, Just Say No
779 	 * (Suggested by gwr)
780 	 */
781 	if ((cflag & CDTRCTS) && (cflag & (CRTSCTS | MDMBUF)))
782 		return (EINVAL);
783 	if (xcs->cs_hwflags & ZS_HWFLAG_NO_DCD) {
784 		if (cflag & MDMBUF)
785 			return (EINVAL);
786 		cflag |= CLOCAL;
787 	}
788 	if ((xcs->cs_hwflags & ZS_HWFLAG_NO_CTS) && (cflag & (CRTSCTS | CDTRCTS)))
789 		return (EINVAL);
790 
791 	/*
792 	 * Output hardware flow control on the chip is horrendous:
793 	 * if carrier detect drops, the receiver is disabled, and if
794 	 * CTS drops, the transmitter is stoped IN MID CHARACTER!
795 	 * Therefore, NEVER set the HFC bit, and instead use the
796 	 * status interrupt to detect CTS changes.
797 	 */
798 	s = splzs();
799 	if ((cflag & (CLOCAL | MDMBUF)) != 0)
800 		cs->cs_rr0_dcd = 0;
801 	else
802 		cs->cs_rr0_dcd = ZSRR0_DCD;
803 	/*
804 	 * The mac hardware only has one output, DTR (HSKo in Mac
805 	 * parlance). In HFC mode, we use it for the functions
806 	 * typically served by RTS and DTR on other ports, so we
807 	 * have to fake the upper layer out some.
808 	 *
809 	 * CRTSCTS we use CTS as an input which tells us when to shut up.
810 	 * We make no effort to shut up the other side of the connection.
811 	 * DTR is used to hang up the modem.
812 	 *
813 	 * In CDTRCTS, we use CTS to tell us to stop, but we use DTR to
814 	 * shut up the other side.
815 	 */
816 	if ((cflag & CRTSCTS) != 0) {
817 		cs->cs_wr5_dtr = ZSWR5_DTR;
818 		cs->cs_wr5_rts = 0;
819 		cs->cs_rr0_cts = ZSRR0_CTS;
820 	} else if ((cflag & CDTRCTS) != 0) {
821 		cs->cs_wr5_dtr = 0;
822 		cs->cs_wr5_rts = ZSWR5_DTR;
823 		cs->cs_rr0_cts = ZSRR0_CTS;
824 	} else if ((cflag & MDMBUF) != 0) {
825 		cs->cs_wr5_dtr = 0;
826 		cs->cs_wr5_rts = ZSWR5_DTR;
827 		cs->cs_rr0_cts = ZSRR0_DCD;
828 	} else {
829 		cs->cs_wr5_dtr = ZSWR5_DTR;
830 		cs->cs_wr5_rts = 0;
831 		cs->cs_rr0_cts = 0;
832 	}
833 	splx(s);
834 
835 	/* Caller will stuff the pending registers. */
836 	return (0);
837 }
838 
839 
840 /*
841  * Read or write the chip with suitable delays.
842  * MacII hardware has the delay built in.
843  * No need for extra delay. :-) However, some clock-chirped
844  * macs, or zsc's on serial add-on boards might need it.
845  */
846 #define	ZS_DELAY()
847 
848 u_char
849 zs_read_reg(cs, reg)
850 	struct zs_chanstate *cs;
851 	u_char reg;
852 {
853 	u_char val;
854 
855 	out8(cs->cs_reg_csr, reg);
856 	ZS_DELAY();
857 	val = in8(cs->cs_reg_csr);
858 	ZS_DELAY();
859 	return val;
860 }
861 
862 void
863 zs_write_reg(cs, reg, val)
864 	struct zs_chanstate *cs;
865 	u_char reg, val;
866 {
867 	out8(cs->cs_reg_csr, reg);
868 	ZS_DELAY();
869 	out8(cs->cs_reg_csr, val);
870 	ZS_DELAY();
871 }
872 
873 u_char zs_read_csr(cs)
874 	struct zs_chanstate *cs;
875 {
876 	register u_char val;
877 
878 	val = in8(cs->cs_reg_csr);
879 	ZS_DELAY();
880 	/* make up for the fact CTS is wired backwards */
881 	val ^= ZSRR0_CTS;
882 	return val;
883 }
884 
885 void  zs_write_csr(cs, val)
886 	struct zs_chanstate *cs;
887 	u_char val;
888 {
889 	/* Note, the csr does not write CTS... */
890 	out8(cs->cs_reg_csr, val);
891 	ZS_DELAY();
892 }
893 
894 u_char zs_read_data(cs)
895 	struct zs_chanstate *cs;
896 {
897 	register u_char val;
898 
899 	val = in8(cs->cs_reg_data);
900 	ZS_DELAY();
901 	return val;
902 }
903 
904 void  zs_write_data(cs, val)
905 	struct zs_chanstate *cs;
906 	u_char val;
907 {
908 	out8(cs->cs_reg_data, val);
909 	ZS_DELAY();
910 }
911 
912 /****************************************************************
913  * Console support functions (powermac specific!)
914  * Note: this code is allowed to know about the layout of
915  * the chip registers, and uses that to keep things simple.
916  * XXX - I think I like the mvme167 code better. -gwr
917  * XXX - Well :-P  :-)  -wrs
918  ****************************************************************/
919 
920 #define zscnpollc	nullcnpollc
921 cons_decl(zs);
922 
923 static int stdin, stdout;
924 
925 /*
926  * Console functions.
927  */
928 
929 /*
930  * zscnprobe is the routine which gets called as the kernel is trying to
931  * figure out where the console should be. Each io driver which might
932  * be the console (as defined in mac68k/conf.c) gets probed. The probe
933  * fills in the consdev structure. Important parts are the device #,
934  * and the console priority. Values are CN_DEAD (don't touch me),
935  * CN_NORMAL (I'm here, but elsewhere might be better), CN_INTERNAL
936  * (the video, better than CN_NORMAL), and CN_REMOTE (pick me!)
937  *
938  * As the mac's a bit different, we do extra work here. We mainly check
939  * to see if we have serial echo going on. Also chould check for default
940  * speeds.
941  */
942 
943 /*
944  * Polled input char.
945  */
946 int
947 zs_getc(v)
948 	void *v;
949 {
950 	register volatile struct zschan *zc = v;
951 	register int s, c, rr0;
952 
953 	s = splhigh();
954 	/* Wait for a character to arrive. */
955 	do {
956 		rr0 = in8(&zc->zc_csr);
957 		ZS_DELAY();
958 	} while ((rr0 & ZSRR0_RX_READY) == 0);
959 
960 	c = in8(&zc->zc_data);
961 	ZS_DELAY();
962 	splx(s);
963 
964 	/*
965 	 * This is used by the kd driver to read scan codes,
966 	 * so don't translate '\r' ==> '\n' here...
967 	 */
968 	return (c);
969 }
970 
971 /*
972  * Polled output char.
973  */
974 void
975 zs_putc(v, c)
976 	void *v;
977 	int c;
978 {
979 	register volatile struct zschan *zc = v;
980 	register int s, rr0;
981 	register long wait = 0;
982 
983 	s = splhigh();
984 	/* Wait for transmitter to become ready. */
985 	do {
986 		rr0 = in8(&zc->zc_csr);
987 		ZS_DELAY();
988 	} while (((rr0 & ZSRR0_TX_READY) == 0) && (wait++ < 1000000));
989 
990 	if ((rr0 & ZSRR0_TX_READY) != 0) {
991 		out8(&zc->zc_data, c);
992 		ZS_DELAY();
993 	}
994 	splx(s);
995 }
996 
997 
998 /*
999  * Polled console input putchar.
1000  */
1001 int
1002 zscngetc(dev)
1003 	dev_t dev;
1004 {
1005 	register volatile struct zschan *zc = zs_conschan;
1006 	register int c;
1007 
1008 	if (zc) {
1009 		c = zs_getc((void *)zc);
1010 	} else {
1011 		char ch = 0;
1012 		OF_read(stdin, &ch, 1);
1013 		c = ch;
1014 	}
1015 	return c;
1016 }
1017 
1018 /*
1019  * Polled console output putchar.
1020  */
1021 void
1022 zscnputc(dev, c)
1023 	dev_t dev;
1024 	int c;
1025 {
1026 	register volatile struct zschan *zc = zs_conschan;
1027 
1028 	if (zc) {
1029 		zs_putc((void *)zc, c);
1030 	} else {
1031 		char ch = c;
1032 		OF_write(stdout, &ch, 1);
1033 	}
1034 }
1035 
1036 /*
1037  * Handle user request to enter kernel debugger.
1038  */
1039 void
1040 zs_abort(cs)
1041 	struct zs_chanstate *cs;
1042 {
1043 	volatile struct zschan *zc = zs_conschan;
1044 	int rr0;
1045 	register long wait = 0;
1046 
1047 	if (zs_cons_canabort == 0)
1048 		return;
1049 
1050 	/* Wait for end of break to avoid PROM abort. */
1051 	do {
1052 		rr0 = in8(&zc->zc_csr);
1053 		ZS_DELAY();
1054 	} while ((rr0 & ZSRR0_BREAK) && (wait++ < ZSABORT_DELAY));
1055 
1056 	if (wait > ZSABORT_DELAY) {
1057 		zs_cons_canabort = 0;
1058 	/* If we time out, turn off the abort ability! */
1059 	}
1060 
1061 #if defined(KGDB)
1062 	kgdb_connect(1);
1063 #elif defined(DDB)
1064 	Debugger();
1065 #endif
1066 }
1067 
1068 extern int ofccngetc __P((dev_t));
1069 extern void ofccnputc __P((dev_t, int));
1070 
1071 struct consdev consdev_zs = {
1072 	zscnprobe,
1073 	zscninit,
1074 	zscngetc,
1075 	zscnputc,
1076 	zscnpollc,
1077 	NULL,
1078 };
1079 
1080 void
1081 zscnprobe(cp)
1082 	struct consdev *cp;
1083 {
1084 	int chosen, pkg;
1085 	int unit = 0;
1086 	char name[16];
1087 	extern const struct cdevsw zstty_cdevsw;
1088 
1089 	if ((chosen = OF_finddevice("/chosen")) == -1)
1090 		return;
1091 
1092 	if (OF_getprop(chosen, "stdin", &stdin, sizeof(stdin)) == -1)
1093 		return;
1094 	if (OF_getprop(chosen, "stdout", &stdout, sizeof(stdout)) == -1)
1095 		return;
1096 
1097 	if ((pkg = OF_instance_to_package(stdin)) == -1)
1098 		return;
1099 
1100 	memset(name, 0, sizeof(name));
1101 	if (OF_getprop(pkg, "device_type", name, sizeof(name)) == -1)
1102 		return;
1103 
1104 	if (strcmp(name, "serial") != 0)
1105 		return;
1106 
1107 	memset(name, 0, sizeof(name));
1108 	if (OF_getprop(pkg, "name", name, sizeof(name)) == -1)
1109 		return;
1110 
1111 	if (strcmp(name, "ch-b") == 0)
1112 		unit = 1;
1113 
1114 	cp->cn_dev = makedev(cdevsw_lookup_major(&zstty_cdevsw), unit);
1115 	cp->cn_pri = CN_REMOTE;
1116 }
1117 
1118 void
1119 zscninit(cp)
1120 	struct consdev *cp;
1121 {
1122 	int escc, escc_ch, obio, zs_offset;
1123 	int ch = 0;
1124 	u_int32_t reg[5];
1125 	char name[16];
1126 
1127 	if ((escc_ch = OF_instance_to_package(stdin)) == -1)
1128 		return;
1129 
1130 	memset(name, 0, sizeof(name));
1131 	if (OF_getprop(escc_ch, "name", name, sizeof(name)) == -1)
1132 		return;
1133 
1134 	if (strcmp(name, "ch-b") == 0)
1135 		ch = 1;
1136 
1137 	if (OF_getprop(escc_ch, "reg", reg, sizeof(reg)) < 4)
1138 		return;
1139 	zs_offset = reg[0];
1140 
1141 	escc = OF_parent(escc_ch);
1142 	obio = OF_parent(escc);
1143 
1144 	if (OF_getprop(obio, "assigned-addresses", reg, sizeof(reg)) < 12)
1145 		return;
1146 	zs_conschan = (void *)(reg[2] + zs_offset);
1147 
1148 	zs_hwflags[0][ch] = ZS_HWFLAG_CONSOLE;
1149 }
1150