xref: /netbsd-src/sys/arch/cesfic/dev/zs.c (revision d710132b4b8ce7f7cccaaf660cb16aa16b4077a0)
1 /*	$NetBSD: zs.c,v 1.7 2003/04/09 11:04:41 drochner Exp $	*/
2 
3 /*-
4  * Copyright (c) 1996 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Gordon W. Ross.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *        This product includes software developed by the NetBSD
21  *        Foundation, Inc. and its contributors.
22  * 4. Neither the name of The NetBSD Foundation nor the names of its
23  *    contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36  * POSSIBILITY OF SUCH DAMAGE.
37  */
38 
39 /*
40  * Zilog Z8530 Dual UART driver (machine-dependent part)
41  *
42  * Runs two serial lines per chip using slave drivers.
43  * Plain tty/async lines use the zs_async slave.
44  */
45 
46 #include "opt_ddb.h"
47 
48 #include <sys/param.h>
49 #include <sys/systm.h>
50 #include <sys/conf.h>
51 #include <sys/device.h>
52 #include <sys/file.h>
53 #include <sys/ioctl.h>
54 #include <sys/kernel.h>
55 #include <sys/malloc.h>
56 #include <sys/proc.h>
57 #include <sys/tty.h>
58 #include <sys/time.h>
59 #include <sys/syslog.h>
60 
61 #include <dev/cons.h>
62 #include <dev/ic/z8530reg.h>
63 
64 #include <machine/cpu.h>
65 
66 #include <machine/z8530var.h>
67 #include <cesfic/dev/zsvar.h>
68 
69 int zs_getc __P((void*));
70 void zs_putc __P((void*, int));
71 
72 static struct zs_chanstate zs_conschan_store;
73 static int zs_hwflags[2][2];
74 int zssoftpending;
75 
76 extern struct cfdriver zsc_cd;
77 
78 u_char zs_init_reg[16] = {
79 	0,	/* 0: CMD (reset, etc.) */
80 	0,	/* 1: No interrupts yet. */
81 	0x18 + ZSHARD_PRI,	/* IVECT */
82 	ZSWR3_RX_8 | ZSWR3_RX_ENABLE,
83 	ZSWR4_CLK_X16 | ZSWR4_ONESB | ZSWR4_EVENP,
84 	ZSWR5_TX_8 | ZSWR5_TX_ENABLE,
85 	0,	/* 6: TXSYNC/SYNCLO */
86 	0,	/* 7: RXSYNC/SYNCHI */
87 	0,	/* 8: alias for data port */
88 	ZSWR9_MASTER_IE,
89 	0,	/*10: Misc. TX/RX control bits */
90 	ZSWR11_TXCLK_BAUD | ZSWR11_RXCLK_BAUD,
91 	11,	/*12: BAUDLO (default=9600) */
92 	0,	/*13: BAUDHI (default=9600) */
93 	ZSWR14_BAUD_ENA | ZSWR14_BAUD_FROM_PCLK,
94 	ZSWR15_BREAK_IE | ZSWR15_DCD_IE,
95 };
96 
97 static int zsc_print __P((void *, const char *));
98 int zscngetc __P((dev_t));
99 void zscnputc __P((dev_t, int));
100 
101 static struct consdev zscons = {
102 	NULL, NULL,
103 	zscngetc, zscnputc, nullcnpollc, NULL, NULL, NULL,
104 	NODEV, 1
105 };
106 
107 void
108 zs_config(zsc, base)
109 	struct zsc_softc *zsc;
110         char *base;
111 {
112 	struct zsc_attach_args zsc_args;
113 	struct zs_chanstate *cs;
114 	int zsc_unit, channel, s;
115 
116 	zsc_unit = zsc->zsc_dev.dv_unit;
117 	printf(": Zilog 8530 SCC\n");
118 
119 	/*
120 	 * Initialize software state for each channel.
121 	 */
122 	for (channel = 0; channel < 2; channel++) {
123 		zsc_args.channel = channel;
124 		zsc_args.hwflags = zs_hwflags[zsc_unit][channel];
125 
126 		/*
127 		 * If we're the console, copy the channel state, and
128 		 * adjust the console channel pointer.
129 		 */
130 		if (zsc_args.hwflags & ZS_HWFLAG_CONSOLE) {
131 			cs = &zs_conschan_store;
132 		} else {
133 			cs = malloc(sizeof(struct zs_chanstate),
134 				    M_DEVBUF, M_NOWAIT | M_ZERO);
135 			if(channel==0){
136 				cs->cs_reg_csr  = base+7;
137 				cs->cs_reg_data = base+15;
138 			} else {
139 				cs->cs_reg_csr  = base+3;
140 				cs->cs_reg_data = base+11;
141 			}
142 			bcopy(zs_init_reg, cs->cs_creg, 16);
143 			bcopy(zs_init_reg, cs->cs_preg, 16);
144 			cs->cs_defspeed = 9600;
145 		}
146 		zsc->zsc_cs[channel] = cs;
147 		simple_lock_init(&cs->cs_lock);
148 
149 		cs->cs_defcflag = CREAD | CS8 | HUPCL;
150 
151 		/* Make these correspond to cs_defcflag (-crtscts) */
152 		cs->cs_rr0_dcd = ZSRR0_DCD;
153 		cs->cs_rr0_cts = 0;
154 		cs->cs_wr5_dtr = ZSWR5_DTR | ZSWR5_RTS;
155 		cs->cs_wr5_rts = 0;
156 
157 		cs->cs_channel = channel;
158 		cs->cs_private = NULL;
159 		cs->cs_ops = &zsops_null;
160 		cs->cs_brg_clk = 4000000 / 16;
161 
162 		/*
163 		 * Clear the master interrupt enable.
164 		 * The INTENA is common to both channels,
165 		 * so just do it on the A channel.
166 		 */
167 		if (channel == 0) {
168 			zs_write_reg(cs, 9, 0);
169 		}
170 
171 		/*
172 		 * Look for a child driver for this channel.
173 		 * The child attach will setup the hardware.
174 		 */
175 		if (!config_found(&zsc->zsc_dev, (void *)&zsc_args, zsc_print)) {
176 			/* No sub-driver.  Just reset it. */
177 			u_char reset = (channel == 0) ?
178 				ZSWR9_A_RESET : ZSWR9_B_RESET;
179 			s = splzs();
180 			zs_write_reg(cs,  9, reset);
181 			splx(s);
182 		}
183 	}
184 }
185 
186 static int
187 zsc_print(aux, name)
188 	void *aux;
189 	const char *name;
190 {
191 	struct zsc_attach_args *args = aux;
192 
193 	if (name != NULL)
194 		aprint_normal("%s: ", name);
195 
196 	if (args->channel != -1)
197 		aprint_normal(" channel %d", args->channel);
198 
199 	return UNCONF;
200 }
201 
202 int
203 zshard(arg)
204 	void *arg;
205 {
206 	register struct zsc_softc *zsc;
207 	register int unit, rval;
208 
209 	rval = 0;
210 	for (unit = 0; unit < zsc_cd.cd_ndevs; unit++) {
211 		zsc = zsc_cd.cd_devs[unit];
212 		if (zsc == NULL)
213 			continue;
214 		rval |= zsc_intr_hard(zsc);
215 		if ((zsc->zsc_cs[0]->cs_softreq) ||
216 			(zsc->zsc_cs[1]->cs_softreq))
217 		{
218 			/* zsc_req_softint(zsc); */
219 			/* We are at splzs here, so no need to lock. */
220 			if (zssoftpending == 0) {
221 				zssoftpending = 1;
222 				setsoftzs();
223 			}
224 		}
225 	}
226 	return (rval);
227 }
228 
229 void
230 softzs()
231 {
232 	register struct zsc_softc *zsc;
233 	register int unit;
234 
235 	/* This is not the only ISR on this IPL. */
236 	if (zssoftpending == 0)
237 		return;
238 
239 	/*
240 	 * The soft intr. bit will be set by zshard only if
241 	 * the variable zssoftpending is zero.
242 	 */
243 	zssoftpending = 0;
244 
245 	for (unit = 0; unit < zsc_cd.cd_ndevs; ++unit) {
246 		zsc = zsc_cd.cd_devs[unit];
247 		if (zsc == NULL)
248 			continue;
249 		(void) zsc_intr_soft(zsc);
250 	}
251 	return;
252 }
253 
254 u_char
255 zs_read_reg(cs, reg)
256 	struct zs_chanstate *cs;
257 	u_char reg;
258 {
259 	u_char val;
260 
261 	*cs->cs_reg_csr = reg;
262 	ZS_DELAY();
263 	val = *cs->cs_reg_csr;
264 	ZS_DELAY();
265 	return val;
266 }
267 
268 void
269 zs_write_reg(cs, reg, val)
270 	struct zs_chanstate *cs;
271 	u_char reg, val;
272 {
273 	*cs->cs_reg_csr = reg;
274 	ZS_DELAY();
275 	*cs->cs_reg_csr = val;
276 	ZS_DELAY();
277 }
278 
279 u_char zs_read_csr(cs)
280 	struct zs_chanstate *cs;
281 {
282 	register u_char val;
283 
284 	val = *cs->cs_reg_csr;
285 	ZS_DELAY();
286 	return val;
287 }
288 
289 void  zs_write_csr(cs, val)
290 	struct zs_chanstate *cs;
291 	u_char val;
292 {
293 	*cs->cs_reg_csr = val;
294 	ZS_DELAY();
295 }
296 
297 u_char zs_read_data(cs)
298 	struct zs_chanstate *cs;
299 {
300 	register u_char val;
301 
302 	val = *cs->cs_reg_data;
303 	ZS_DELAY();
304 	return val;
305 }
306 
307 void  zs_write_data(cs, val)
308 	struct zs_chanstate *cs;
309 	u_char val;
310 {
311 	*cs->cs_reg_data = val;
312 	ZS_DELAY();
313 }
314 
315 int
316 zs_set_speed(cs, bps)
317 	struct zs_chanstate *cs;
318 	int bps;	/* bits per second */
319 {
320 	int tconst, real_bps;
321 
322 	tconst = BPS_TO_TCONST(cs->cs_brg_clk, bps);
323 
324 	if (tconst < 0)
325 		return (EINVAL);
326 
327 	/* Convert back to make sure we can do it. */
328 	real_bps = TCONST_TO_BPS(cs->cs_brg_clk, tconst);
329 #if 0
330 	/* XXX - Allow some tolerance here? */
331 	if (real_bps != bps)
332 		return (EINVAL);
333 #endif
334 	cs->cs_preg[12] = tconst;
335 	cs->cs_preg[13] = tconst >> 8;
336 
337 	return (0);
338 }
339 
340 int
341 zs_set_modes(cs, cflag)
342 	struct zs_chanstate *cs;
343 	int cflag;	/* bits per second */
344 {
345 	int s;
346 
347 	/*
348 	 * Output hardware flow control on the chip is horrendous:
349 	 * if carrier detect drops, the receiver is disabled, and if
350 	 * CTS drops, the transmitter is stoped IN MID CHARACTER!
351 	 * Therefore, NEVER set the HFC bit, and instead use the
352 	 * status interrupt to detect CTS changes.
353 	 */
354 	s = splzs();
355 #if 0	/* XXX - See below. */
356 	if (cflag & CLOCAL) {
357 		cs->cs_rr0_dcd = 0;
358 		cs->cs_preg[15] &= ~ZSWR15_DCD_IE;
359 	} else {
360 		/* XXX - Need to notice DCD change here... */
361 		cs->cs_rr0_dcd = ZSRR0_DCD;
362 		cs->cs_preg[15] |= ZSWR15_DCD_IE;
363 	}
364 #endif	/* XXX */
365 	if (cflag & CRTSCTS) {
366 		cs->cs_wr5_dtr = ZSWR5_DTR;
367 		cs->cs_wr5_rts = ZSWR5_RTS;
368 		cs->cs_rr0_cts = ZSRR0_CTS;
369 		cs->cs_preg[15] |= ZSWR15_CTS_IE;
370 	} else {
371 		cs->cs_wr5_dtr = ZSWR5_DTR | ZSWR5_RTS;
372 		cs->cs_wr5_rts = 0;
373 		cs->cs_rr0_cts = 0;
374 		cs->cs_preg[15] &= ~ZSWR15_CTS_IE;
375 	}
376 	splx(s);
377 
378 	/* Caller will stuff the pending registers. */
379 	return (0);
380 }
381 
382 /*
383  * Handle user request to enter kernel debugger.
384  */
385 void
386 zs_abort(cs)
387 	struct zs_chanstate *cs;
388 {
389 	int rr0;
390 
391 	/* Wait for end of break to avoid PROM abort. */
392 	/* XXX - Limit the wait? */
393 	do {
394 		rr0 = *cs->cs_reg_csr;
395 		ZS_DELAY();
396 	} while (rr0 & ZSRR0_BREAK);
397 #ifdef DDB
398 	console_debugger();
399 #endif
400 }
401 
402 /*
403  * Polled input char.
404  */
405 int
406 zs_getc(arg)
407 	void *arg;
408 {
409 	register struct zs_chanstate *cs = arg;
410 	register int s, c, rr0, stat;
411 
412 	s = splhigh();
413 top:
414 	/* Wait for a character to arrive. */
415 	do {
416 		rr0 = *cs->cs_reg_csr;
417 		ZS_DELAY();
418 	} while ((rr0 & ZSRR0_RX_READY) == 0);
419 
420 	/* Read error register. */
421 	stat = zs_read_reg(cs, 1) & (ZSRR1_FE | ZSRR1_DO | ZSRR1_PE);
422 	if (stat) {
423 		zs_write_csr(cs, ZSM_RESET_ERR);
424 		goto top;
425 	}
426 
427 	/* Read character. */
428 	c = *cs->cs_reg_data;
429 	ZS_DELAY();
430 	splx(s);
431 
432 	return (c);
433 }
434 
435 /*
436  * Polled output char.
437  */
438 void
439 zs_putc(arg, c)
440 	void *arg;
441 	int c;
442 {
443 	register struct zs_chanstate *cs = arg;
444 	register int s, rr0;
445 
446 	s = splhigh();
447 	/* Wait for transmitter to become ready. */
448 	do {
449 		rr0 = *cs->cs_reg_csr;
450 		ZS_DELAY();
451 	} while ((rr0 & ZSRR0_TX_READY) == 0);
452 
453 	*cs->cs_reg_data = c;
454 	ZS_DELAY();
455 	splx(s);
456 }
457 
458 int zscngetc(dev)
459 dev_t dev;
460 {
461 	register struct zs_chanstate *cs = &zs_conschan_store;
462 	register int c;
463 
464 	c = zs_getc(cs);
465 	return (c);
466 }
467 
468 void zscnputc(dev, c)
469 dev_t dev;
470 int c;
471 {
472 	register struct zs_chanstate *cs = &zs_conschan_store;
473 
474 	zs_putc(cs, c);
475 }
476 
477 /*
478  * Common parts of console init.
479  */
480 void
481 zs_cninit(base)
482 	void *base;
483 {
484 	struct zs_chanstate *cs;
485 	/*
486 	 * Pointer to channel state.  Later, the console channel
487 	 * state is copied into the softc, and the console channel
488 	 * pointer adjusted to point to the new copy.
489 	 */
490 	cs = &zs_conschan_store;
491 	zs_hwflags[0][0] = ZS_HWFLAG_CONSOLE;
492 
493 	/* Setup temporary chanstate. */
494 	cs->cs_reg_csr  = (char *)base + 7;
495 	cs->cs_reg_data = (char *)base + 15;
496 
497 	/* Initialize the pending registers. */
498 	bcopy(zs_init_reg, cs->cs_preg, 16);
499 	cs->cs_preg[5] |= (ZSWR5_DTR | ZSWR5_RTS);
500 
501 	/* XXX: Preserve BAUD rate from boot loader. */
502 	/* XXX: Also, why reset the chip here? -gwr */
503 	/* cs->cs_defspeed = zs_get_speed(cs); */
504 	cs->cs_defspeed = 9600;	/* XXX */
505 
506 	/* Clear the master interrupt enable. */
507 	zs_write_reg(cs, 9, 0);
508 
509 	/* Reset the whole SCC chip. */
510 	zs_write_reg(cs, 9, ZSWR9_HARD_RESET);
511 
512 	/* Copy "pending" to "current" and H/W. */
513 	zs_loadchannelregs(cs);
514 
515 	/* Point the console at the SCC. */
516 	cn_tab = &zscons;
517 }
518