xref: /netbsd/sys/arch/cesfic/dev/zs.c (revision bf9ec67e)
1 /*	$NetBSD: zs.c,v 1.1 2001/05/14 18:23:07 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 zs_major = 10;
75 int zssoftpending;
76 
77 extern struct cfdriver zsc_cd;
78 
79 u_char zs_init_reg[16] = {
80 	0,	/* 0: CMD (reset, etc.) */
81 	0,	/* 1: No interrupts yet. */
82 	0x18 + ZSHARD_PRI,	/* IVECT */
83 	ZSWR3_RX_8 | ZSWR3_RX_ENABLE,
84 	ZSWR4_CLK_X16 | ZSWR4_ONESB | ZSWR4_EVENP,
85 	ZSWR5_TX_8 | ZSWR5_TX_ENABLE,
86 	0,	/* 6: TXSYNC/SYNCLO */
87 	0,	/* 7: RXSYNC/SYNCHI */
88 	0,	/* 8: alias for data port */
89 	ZSWR9_MASTER_IE,
90 	0,	/*10: Misc. TX/RX control bits */
91 	ZSWR11_TXCLK_BAUD | ZSWR11_RXCLK_BAUD,
92 	11,	/*12: BAUDLO (default=9600) */
93 	0,	/*13: BAUDHI (default=9600) */
94 	ZSWR14_BAUD_ENA | ZSWR14_BAUD_FROM_PCLK,
95 	ZSWR15_BREAK_IE | ZSWR15_DCD_IE,
96 };
97 
98 static int zsc_print __P((void *, const char *));
99 int zscngetc __P((dev_t));
100 void zscnputc __P((dev_t, int));
101 
102 static struct consdev zscons = { NULL, NULL,
103 	zscngetc, zscnputc, nullcnpollc, 0, NODEV, 1 };
104 
105 void
106 zs_config(zsc, base)
107 	struct zsc_softc *zsc;
108         char *base;
109 {
110 	struct zsc_attach_args zsc_args;
111 	struct zs_chanstate *cs;
112 	int zsc_unit, channel, s;
113 
114 	zsc_unit = zsc->zsc_dev.dv_unit;
115 	printf(": Zilog 8530 SCC\n");
116 
117 	/*
118 	 * Initialize software state for each channel.
119 	 */
120 	for (channel = 0; channel < 2; channel++) {
121 		zsc_args.channel = channel;
122 		zsc_args.hwflags = zs_hwflags[zsc_unit][channel];
123 
124 		/*
125 		 * If we're the console, copy the channel state, and
126 		 * adjust the console channel pointer.
127 		 */
128 		if (zsc_args.hwflags & ZS_HWFLAG_CONSOLE) {
129 			cs = &zs_conschan_store;
130 		} else {
131 			cs = malloc(sizeof(struct zs_chanstate),
132 				    M_DEVBUF, M_NOWAIT);
133 			if(channel==0){
134 				cs->cs_reg_csr  = base+7;
135 				cs->cs_reg_data = base+15;
136 			} else {
137 				cs->cs_reg_csr  = base+3;
138 				cs->cs_reg_data = base+11;
139 			}
140 			bcopy(zs_init_reg, cs->cs_creg, 16);
141 			bcopy(zs_init_reg, cs->cs_preg, 16);
142 			cs->cs_defspeed = 9600;
143 		}
144 		zsc->zsc_cs[channel] = cs;
145 
146 		cs->cs_defcflag = CREAD | CS8 | HUPCL;
147 
148 		/* Make these correspond to cs_defcflag (-crtscts) */
149 		cs->cs_rr0_dcd = ZSRR0_DCD;
150 		cs->cs_rr0_cts = 0;
151 		cs->cs_wr5_dtr = ZSWR5_DTR | ZSWR5_RTS;
152 		cs->cs_wr5_rts = 0;
153 
154 		cs->cs_channel = channel;
155 		cs->cs_private = NULL;
156 		cs->cs_ops = &zsops_null;
157 		cs->cs_brg_clk = 4000000 / 16;
158 
159 		/*
160 		 * Clear the master interrupt enable.
161 		 * The INTENA is common to both channels,
162 		 * so just do it on the A channel.
163 		 */
164 		if (channel == 0) {
165 			zs_write_reg(cs, 9, 0);
166 		}
167 
168 		/*
169 		 * Look for a child driver for this channel.
170 		 * The child attach will setup the hardware.
171 		 */
172 		if (!config_found(&zsc->zsc_dev, (void *)&zsc_args, zsc_print)) {
173 			/* No sub-driver.  Just reset it. */
174 			u_char reset = (channel == 0) ?
175 				ZSWR9_A_RESET : ZSWR9_B_RESET;
176 			s = splzs();
177 			zs_write_reg(cs,  9, reset);
178 			splx(s);
179 		}
180 	}
181 }
182 
183 static int
184 zsc_print(aux, name)
185 	void *aux;
186 	const char *name;
187 {
188 	struct zsc_attach_args *args = aux;
189 
190 	if (name != NULL)
191 		printf("%s: ", name);
192 
193 	if (args->channel != -1)
194 		printf(" channel %d", args->channel);
195 
196 	return UNCONF;
197 }
198 
199 int
200 zshard(arg)
201 	void *arg;
202 {
203 	register struct zsc_softc *zsc;
204 	register int unit, rval;
205 
206 	rval = 0;
207 	for (unit = 0; unit < zsc_cd.cd_ndevs; unit++) {
208 		zsc = zsc_cd.cd_devs[unit];
209 		if (zsc == NULL)
210 			continue;
211 		rval |= zsc_intr_hard(zsc);
212 		if ((zsc->zsc_cs[0]->cs_softreq) ||
213 			(zsc->zsc_cs[1]->cs_softreq))
214 		{
215 			/* zsc_req_softint(zsc); */
216 			/* We are at splzs here, so no need to lock. */
217 			if (zssoftpending == 0) {
218 				zssoftpending = 1;
219 				setsoftzs();
220 			}
221 		}
222 	}
223 	return (rval);
224 }
225 
226 void
227 softzs()
228 {
229 	register struct zsc_softc *zsc;
230 	register int unit;
231 
232 	/* This is not the only ISR on this IPL. */
233 	if (zssoftpending == 0)
234 		return;
235 
236 	/*
237 	 * The soft intr. bit will be set by zshard only if
238 	 * the variable zssoftpending is zero.
239 	 */
240 	zssoftpending = 0;
241 
242 	for (unit = 0; unit < zsc_cd.cd_ndevs; ++unit) {
243 		zsc = zsc_cd.cd_devs[unit];
244 		if (zsc == NULL)
245 			continue;
246 		(void) zsc_intr_soft(zsc);
247 	}
248 	return;
249 }
250 
251 u_char
252 zs_read_reg(cs, reg)
253 	struct zs_chanstate *cs;
254 	u_char reg;
255 {
256 	u_char val;
257 
258 	*cs->cs_reg_csr = reg;
259 	ZS_DELAY();
260 	val = *cs->cs_reg_csr;
261 	ZS_DELAY();
262 	return val;
263 }
264 
265 void
266 zs_write_reg(cs, reg, val)
267 	struct zs_chanstate *cs;
268 	u_char reg, val;
269 {
270 	*cs->cs_reg_csr = reg;
271 	ZS_DELAY();
272 	*cs->cs_reg_csr = val;
273 	ZS_DELAY();
274 }
275 
276 u_char zs_read_csr(cs)
277 	struct zs_chanstate *cs;
278 {
279 	register u_char val;
280 
281 	val = *cs->cs_reg_csr;
282 	ZS_DELAY();
283 	return val;
284 }
285 
286 void  zs_write_csr(cs, val)
287 	struct zs_chanstate *cs;
288 	u_char val;
289 {
290 	*cs->cs_reg_csr = val;
291 	ZS_DELAY();
292 }
293 
294 u_char zs_read_data(cs)
295 	struct zs_chanstate *cs;
296 {
297 	register u_char val;
298 
299 	val = *cs->cs_reg_data;
300 	ZS_DELAY();
301 	return val;
302 }
303 
304 void  zs_write_data(cs, val)
305 	struct zs_chanstate *cs;
306 	u_char val;
307 {
308 	*cs->cs_reg_data = val;
309 	ZS_DELAY();
310 }
311 
312 int
313 zs_set_speed(cs, bps)
314 	struct zs_chanstate *cs;
315 	int bps;	/* bits per second */
316 {
317 	int tconst, real_bps;
318 
319 	tconst = BPS_TO_TCONST(cs->cs_brg_clk, bps);
320 
321 	if (tconst < 0)
322 		return (EINVAL);
323 
324 	/* Convert back to make sure we can do it. */
325 	real_bps = TCONST_TO_BPS(cs->cs_brg_clk, tconst);
326 #if 0
327 	/* XXX - Allow some tolerance here? */
328 	if (real_bps != bps)
329 		return (EINVAL);
330 #endif
331 	cs->cs_preg[12] = tconst;
332 	cs->cs_preg[13] = tconst >> 8;
333 
334 	return (0);
335 }
336 
337 int
338 zs_set_modes(cs, cflag)
339 	struct zs_chanstate *cs;
340 	int cflag;	/* bits per second */
341 {
342 	int s;
343 
344 	/*
345 	 * Output hardware flow control on the chip is horrendous:
346 	 * if carrier detect drops, the receiver is disabled, and if
347 	 * CTS drops, the transmitter is stoped IN MID CHARACTER!
348 	 * Therefore, NEVER set the HFC bit, and instead use the
349 	 * status interrupt to detect CTS changes.
350 	 */
351 	s = splzs();
352 #if 0	/* XXX - See below. */
353 	if (cflag & CLOCAL) {
354 		cs->cs_rr0_dcd = 0;
355 		cs->cs_preg[15] &= ~ZSWR15_DCD_IE;
356 	} else {
357 		/* XXX - Need to notice DCD change here... */
358 		cs->cs_rr0_dcd = ZSRR0_DCD;
359 		cs->cs_preg[15] |= ZSWR15_DCD_IE;
360 	}
361 #endif	/* XXX */
362 	if (cflag & CRTSCTS) {
363 		cs->cs_wr5_dtr = ZSWR5_DTR;
364 		cs->cs_wr5_rts = ZSWR5_RTS;
365 		cs->cs_rr0_cts = ZSRR0_CTS;
366 		cs->cs_preg[15] |= ZSWR15_CTS_IE;
367 	} else {
368 		cs->cs_wr5_dtr = ZSWR5_DTR | ZSWR5_RTS;
369 		cs->cs_wr5_rts = 0;
370 		cs->cs_rr0_cts = 0;
371 		cs->cs_preg[15] &= ~ZSWR15_CTS_IE;
372 	}
373 	splx(s);
374 
375 	/* Caller will stuff the pending registers. */
376 	return (0);
377 }
378 
379 /*
380  * Handle user request to enter kernel debugger.
381  */
382 void
383 zs_abort(cs)
384 	struct zs_chanstate *cs;
385 {
386 	int rr0;
387 
388 	/* Wait for end of break to avoid PROM abort. */
389 	/* XXX - Limit the wait? */
390 	do {
391 		rr0 = *cs->cs_reg_csr;
392 		ZS_DELAY();
393 	} while (rr0 & ZSRR0_BREAK);
394 #ifdef DDB
395 	console_debugger();
396 #endif
397 }
398 
399 /*
400  * Polled input char.
401  */
402 int
403 zs_getc(arg)
404 	void *arg;
405 {
406 	register struct zs_chanstate *cs = arg;
407 	register int s, c, rr0, stat;
408 
409 	s = splhigh();
410 top:
411 	/* Wait for a character to arrive. */
412 	do {
413 		rr0 = *cs->cs_reg_csr;
414 		ZS_DELAY();
415 	} while ((rr0 & ZSRR0_RX_READY) == 0);
416 
417 	/* Read error register. */
418 	stat = zs_read_reg(cs, 1) & (ZSRR1_FE | ZSRR1_DO | ZSRR1_PE);
419 	if (stat) {
420 		zs_write_csr(cs, ZSM_RESET_ERR);
421 		goto top;
422 	}
423 
424 	/* Read character. */
425 	c = *cs->cs_reg_data;
426 	ZS_DELAY();
427 	splx(s);
428 
429 	return (c);
430 }
431 
432 /*
433  * Polled output char.
434  */
435 void
436 zs_putc(arg, c)
437 	void *arg;
438 	int c;
439 {
440 	register struct zs_chanstate *cs = arg;
441 	register int s, rr0;
442 
443 	s = splhigh();
444 	/* Wait for transmitter to become ready. */
445 	do {
446 		rr0 = *cs->cs_reg_csr;
447 		ZS_DELAY();
448 	} while ((rr0 & ZSRR0_TX_READY) == 0);
449 
450 	*cs->cs_reg_data = c;
451 	ZS_DELAY();
452 	splx(s);
453 }
454 
455 int zscngetc(dev)
456 dev_t dev;
457 {
458 	register struct zs_chanstate *cs = &zs_conschan_store;
459 	register int c;
460 
461 	c = zs_getc(cs);
462 	return (c);
463 }
464 
465 void zscnputc(dev, c)
466 dev_t dev;
467 int c;
468 {
469 	register struct zs_chanstate *cs = &zs_conschan_store;
470 
471 	zs_putc(cs, c);
472 }
473 
474 /*
475  * Common parts of console init.
476  */
477 void
478 zs_cninit(base)
479 	void *base;
480 {
481 	struct zs_chanstate *cs;
482 	/*
483 	 * Pointer to channel state.  Later, the console channel
484 	 * state is copied into the softc, and the console channel
485 	 * pointer adjusted to point to the new copy.
486 	 */
487 	cs = &zs_conschan_store;
488 	zs_hwflags[0][0] = ZS_HWFLAG_CONSOLE;
489 
490 	/* Setup temporary chanstate. */
491 	cs->cs_reg_csr  = base+7;
492 	cs->cs_reg_data = base+15;
493 
494 	/* Initialize the pending registers. */
495 	bcopy(zs_init_reg, cs->cs_preg, 16);
496 	cs->cs_preg[5] |= (ZSWR5_DTR | ZSWR5_RTS);
497 
498 	/* XXX: Preserve BAUD rate from boot loader. */
499 	/* XXX: Also, why reset the chip here? -gwr */
500 	/* cs->cs_defspeed = zs_get_speed(cs); */
501 	cs->cs_defspeed = 9600;	/* XXX */
502 
503 	/* Clear the master interrupt enable. */
504 	zs_write_reg(cs, 9, 0);
505 
506 	/* Reset the whole SCC chip. */
507 	zs_write_reg(cs, 9, ZSWR9_HARD_RESET);
508 
509 	/* Copy "pending" to "current" and H/W. */
510 	zs_loadchannelregs(cs);
511 
512 	/* Point the console at the SCC. */
513 	cn_tab = &zscons;
514 }
515