xref: /netbsd-src/sys/arch/cesfic/dev/zs.c (revision 8b0f9554ff8762542c4defc4f70e1eb76fb508fa)
1 /*	$NetBSD: zs.c,v 1.13 2007/12/03 15:33:25 ad 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 <sys/cdefs.h>
47 __KERNEL_RCSID(0, "$NetBSD: zs.c,v 1.13 2007/12/03 15:33:25 ad Exp $");
48 
49 #include "opt_ddb.h"
50 
51 #include <sys/param.h>
52 #include <sys/systm.h>
53 #include <sys/conf.h>
54 #include <sys/device.h>
55 #include <sys/file.h>
56 #include <sys/ioctl.h>
57 #include <sys/kernel.h>
58 #include <sys/malloc.h>
59 #include <sys/proc.h>
60 #include <sys/tty.h>
61 #include <sys/time.h>
62 #include <sys/syslog.h>
63 
64 #include <dev/cons.h>
65 #include <dev/ic/z8530reg.h>
66 
67 #include <machine/cpu.h>
68 
69 #include <machine/z8530var.h>
70 #include <cesfic/dev/zsvar.h>
71 
72 int zs_getc __P((void*));
73 void zs_putc __P((void*, int));
74 
75 static struct zs_chanstate zs_conschan_store;
76 static int zs_hwflags[2][2];
77 
78 extern struct cfdriver zsc_cd;
79 
80 u_char zs_init_reg[16] = {
81 	0,	/* 0: CMD (reset, etc.) */
82 	0,	/* 1: No interrupts yet. */
83 	0x18 + ZSHARD_PRI,	/* IVECT */
84 	ZSWR3_RX_8 | ZSWR3_RX_ENABLE,
85 	ZSWR4_CLK_X16 | ZSWR4_ONESB | ZSWR4_EVENP,
86 	ZSWR5_TX_8 | ZSWR5_TX_ENABLE,
87 	0,	/* 6: TXSYNC/SYNCLO */
88 	0,	/* 7: RXSYNC/SYNCHI */
89 	0,	/* 8: alias for data port */
90 	ZSWR9_MASTER_IE,
91 	0,	/*10: Misc. TX/RX control bits */
92 	ZSWR11_TXCLK_BAUD | ZSWR11_RXCLK_BAUD,
93 	11,	/*12: BAUDLO (default=9600) */
94 	0,	/*13: BAUDHI (default=9600) */
95 	ZSWR14_BAUD_ENA | ZSWR14_BAUD_FROM_PCLK,
96 	ZSWR15_BREAK_IE | ZSWR15_DCD_IE,
97 };
98 
99 static int zsc_print __P((void *, const char *));
100 int zscngetc __P((dev_t));
101 void zscnputc __P((dev_t, int));
102 
103 static struct consdev zscons = {
104 	NULL, NULL,
105 	zscngetc, zscnputc, nullcnpollc, NULL, NULL, NULL,
106 	NODEV, 1
107 };
108 
109 void
110 zs_config(zsc, base)
111 	struct zsc_softc *zsc;
112         char *base;
113 {
114 	struct zsc_attach_args zsc_args;
115 	struct zs_chanstate *cs;
116 	int zsc_unit, channel, s;
117 
118 	zsc_unit = device_unit(&zsc->zsc_dev);
119 	printf(": Zilog 8530 SCC\n");
120 
121 	/*
122 	 * Initialize software state for each channel.
123 	 */
124 	for (channel = 0; channel < 2; channel++) {
125 		zsc_args.channel = channel;
126 		zsc_args.hwflags = zs_hwflags[zsc_unit][channel];
127 
128 		/*
129 		 * If we're the console, copy the channel state, and
130 		 * adjust the console channel pointer.
131 		 */
132 		if (zsc_args.hwflags & ZS_HWFLAG_CONSOLE) {
133 			cs = &zs_conschan_store;
134 		} else {
135 			cs = malloc(sizeof(struct zs_chanstate),
136 				    M_DEVBUF, M_NOWAIT | M_ZERO);
137 			if(channel==0){
138 				cs->cs_reg_csr  = base+7;
139 				cs->cs_reg_data = base+15;
140 			} else {
141 				cs->cs_reg_csr  = base+3;
142 				cs->cs_reg_data = base+11;
143 			}
144 			bcopy(zs_init_reg, cs->cs_creg, 16);
145 			bcopy(zs_init_reg, cs->cs_preg, 16);
146 			cs->cs_defspeed = 9600;
147 		}
148 		zsc->zsc_cs[channel] = cs;
149 		zs_lock_init(cs);
150 
151 		cs->cs_defcflag = CREAD | CS8 | HUPCL;
152 
153 		/* Make these correspond to cs_defcflag (-crtscts) */
154 		cs->cs_rr0_dcd = ZSRR0_DCD;
155 		cs->cs_rr0_cts = 0;
156 		cs->cs_wr5_dtr = ZSWR5_DTR | ZSWR5_RTS;
157 		cs->cs_wr5_rts = 0;
158 
159 		cs->cs_channel = channel;
160 		cs->cs_private = NULL;
161 		cs->cs_ops = &zsops_null;
162 		cs->cs_brg_clk = 4000000 / 16;
163 
164 		/*
165 		 * Clear the master interrupt enable.
166 		 * The INTENA is common to both channels,
167 		 * so just do it on the A channel.
168 		 */
169 		if (channel == 0) {
170 			zs_write_reg(cs, 9, 0);
171 		}
172 
173 		/*
174 		 * Look for a child driver for this channel.
175 		 * The child attach will setup the hardware.
176 		 */
177 		if (!config_found(&zsc->zsc_dev, (void *)&zsc_args, zsc_print)) {
178 			/* No sub-driver.  Just reset it. */
179 			u_char reset = (channel == 0) ?
180 				ZSWR9_A_RESET : ZSWR9_B_RESET;
181 			s = splzs();
182 			zs_write_reg(cs,  9, reset);
183 			splx(s);
184 		}
185 	}
186 }
187 
188 static int
189 zsc_print(aux, name)
190 	void *aux;
191 	const char *name;
192 {
193 	struct zsc_attach_args *args = aux;
194 
195 	if (name != NULL)
196 		aprint_normal("%s: ", name);
197 
198 	if (args->channel != -1)
199 		aprint_normal(" channel %d", args->channel);
200 
201 	return UNCONF;
202 }
203 
204 int
205 zshard(arg)
206 	void *arg;
207 {
208 	register struct zsc_softc *zsc;
209 	register int unit, rval;
210 
211 	rval = 0;
212 	for (unit = 0; unit < zsc_cd.cd_ndevs; unit++) {
213 		zsc = zsc_cd.cd_devs[unit];
214 		if (zsc == NULL)
215 			continue;
216 		rval |= zsc_intr_hard(zsc);
217 		if ((zsc->zsc_cs[0]->cs_softreq) ||
218 		    (zsc->zsc_cs[1]->cs_softreq)) {
219 			softint_schedule(zsc->zsc_softintr_cookie);
220 		}
221 	}
222 	return (rval);
223 }
224 
225 u_char
226 zs_read_reg(cs, reg)
227 	struct zs_chanstate *cs;
228 	u_char reg;
229 {
230 	u_char val;
231 
232 	*cs->cs_reg_csr = reg;
233 	ZS_DELAY();
234 	val = *cs->cs_reg_csr;
235 	ZS_DELAY();
236 	return val;
237 }
238 
239 void
240 zs_write_reg(cs, reg, val)
241 	struct zs_chanstate *cs;
242 	u_char reg, val;
243 {
244 	*cs->cs_reg_csr = reg;
245 	ZS_DELAY();
246 	*cs->cs_reg_csr = val;
247 	ZS_DELAY();
248 }
249 
250 u_char zs_read_csr(cs)
251 	struct zs_chanstate *cs;
252 {
253 	register u_char val;
254 
255 	val = *cs->cs_reg_csr;
256 	ZS_DELAY();
257 	return val;
258 }
259 
260 void  zs_write_csr(cs, val)
261 	struct zs_chanstate *cs;
262 	u_char val;
263 {
264 	*cs->cs_reg_csr = val;
265 	ZS_DELAY();
266 }
267 
268 u_char zs_read_data(cs)
269 	struct zs_chanstate *cs;
270 {
271 	register u_char val;
272 
273 	val = *cs->cs_reg_data;
274 	ZS_DELAY();
275 	return val;
276 }
277 
278 void  zs_write_data(cs, val)
279 	struct zs_chanstate *cs;
280 	u_char val;
281 {
282 	*cs->cs_reg_data = val;
283 	ZS_DELAY();
284 }
285 
286 int
287 zs_set_speed(cs, bps)
288 	struct zs_chanstate *cs;
289 	int bps;	/* bits per second */
290 {
291 	int tconst, real_bps;
292 
293 	tconst = BPS_TO_TCONST(cs->cs_brg_clk, bps);
294 
295 	if (tconst < 0)
296 		return (EINVAL);
297 
298 	/* Convert back to make sure we can do it. */
299 	real_bps = TCONST_TO_BPS(cs->cs_brg_clk, tconst);
300 #if 0
301 	/* XXX - Allow some tolerance here? */
302 	if (real_bps != bps)
303 		return (EINVAL);
304 #endif
305 	cs->cs_preg[12] = tconst;
306 	cs->cs_preg[13] = tconst >> 8;
307 
308 	return (0);
309 }
310 
311 int
312 zs_set_modes(cs, cflag)
313 	struct zs_chanstate *cs;
314 	int cflag;	/* bits per second */
315 {
316 	int s;
317 
318 	/*
319 	 * Output hardware flow control on the chip is horrendous:
320 	 * if carrier detect drops, the receiver is disabled, and if
321 	 * CTS drops, the transmitter is stoped IN MID CHARACTER!
322 	 * Therefore, NEVER set the HFC bit, and instead use the
323 	 * status interrupt to detect CTS changes.
324 	 */
325 	s = splzs();
326 #if 0	/* XXX - See below. */
327 	if (cflag & CLOCAL) {
328 		cs->cs_rr0_dcd = 0;
329 		cs->cs_preg[15] &= ~ZSWR15_DCD_IE;
330 	} else {
331 		/* XXX - Need to notice DCD change here... */
332 		cs->cs_rr0_dcd = ZSRR0_DCD;
333 		cs->cs_preg[15] |= ZSWR15_DCD_IE;
334 	}
335 #endif	/* XXX */
336 	if (cflag & CRTSCTS) {
337 		cs->cs_wr5_dtr = ZSWR5_DTR;
338 		cs->cs_wr5_rts = ZSWR5_RTS;
339 		cs->cs_rr0_cts = ZSRR0_CTS;
340 		cs->cs_preg[15] |= ZSWR15_CTS_IE;
341 	} else {
342 		cs->cs_wr5_dtr = ZSWR5_DTR | ZSWR5_RTS;
343 		cs->cs_wr5_rts = 0;
344 		cs->cs_rr0_cts = 0;
345 		cs->cs_preg[15] &= ~ZSWR15_CTS_IE;
346 	}
347 	splx(s);
348 
349 	/* Caller will stuff the pending registers. */
350 	return (0);
351 }
352 
353 /*
354  * Handle user request to enter kernel debugger.
355  */
356 void
357 zs_abort(cs)
358 	struct zs_chanstate *cs;
359 {
360 	int rr0;
361 
362 	/* Wait for end of break to avoid PROM abort. */
363 	/* XXX - Limit the wait? */
364 	do {
365 		rr0 = *cs->cs_reg_csr;
366 		ZS_DELAY();
367 	} while (rr0 & ZSRR0_BREAK);
368 #ifdef DDB
369 	console_debugger();
370 #endif
371 }
372 
373 /*
374  * Polled input char.
375  */
376 int
377 zs_getc(arg)
378 	void *arg;
379 {
380 	register struct zs_chanstate *cs = arg;
381 	register int s, c, rr0, stat;
382 
383 	s = splhigh();
384 top:
385 	/* Wait for a character to arrive. */
386 	do {
387 		rr0 = *cs->cs_reg_csr;
388 		ZS_DELAY();
389 	} while ((rr0 & ZSRR0_RX_READY) == 0);
390 
391 	/* Read error register. */
392 	stat = zs_read_reg(cs, 1) & (ZSRR1_FE | ZSRR1_DO | ZSRR1_PE);
393 	if (stat) {
394 		zs_write_csr(cs, ZSM_RESET_ERR);
395 		goto top;
396 	}
397 
398 	/* Read character. */
399 	c = *cs->cs_reg_data;
400 	ZS_DELAY();
401 	splx(s);
402 
403 	return (c);
404 }
405 
406 /*
407  * Polled output char.
408  */
409 void
410 zs_putc(arg, c)
411 	void *arg;
412 	int c;
413 {
414 	register struct zs_chanstate *cs = arg;
415 	register int s, rr0;
416 
417 	s = splhigh();
418 	/* Wait for transmitter to become ready. */
419 	do {
420 		rr0 = *cs->cs_reg_csr;
421 		ZS_DELAY();
422 	} while ((rr0 & ZSRR0_TX_READY) == 0);
423 
424 	*cs->cs_reg_data = c;
425 	ZS_DELAY();
426 	splx(s);
427 }
428 
429 int zscngetc(dev)
430 dev_t dev;
431 {
432 	register struct zs_chanstate *cs = &zs_conschan_store;
433 	register int c;
434 
435 	c = zs_getc(cs);
436 	return (c);
437 }
438 
439 void zscnputc(dev, c)
440 dev_t dev;
441 int c;
442 {
443 	register struct zs_chanstate *cs = &zs_conschan_store;
444 
445 	zs_putc(cs, c);
446 }
447 
448 /*
449  * Common parts of console init.
450  */
451 void
452 zs_cninit(base)
453 	void *base;
454 {
455 	struct zs_chanstate *cs;
456 	/*
457 	 * Pointer to channel state.  Later, the console channel
458 	 * state is copied into the softc, and the console channel
459 	 * pointer adjusted to point to the new copy.
460 	 */
461 	cs = &zs_conschan_store;
462 	zs_hwflags[0][0] = ZS_HWFLAG_CONSOLE;
463 
464 	/* Setup temporary chanstate. */
465 	cs->cs_reg_csr  = (char *)base + 7;
466 	cs->cs_reg_data = (char *)base + 15;
467 
468 	/* Initialize the pending registers. */
469 	bcopy(zs_init_reg, cs->cs_preg, 16);
470 	cs->cs_preg[5] |= (ZSWR5_DTR | ZSWR5_RTS);
471 
472 	/* XXX: Preserve BAUD rate from boot loader. */
473 	/* XXX: Also, why reset the chip here? -gwr */
474 	/* cs->cs_defspeed = zs_get_speed(cs); */
475 	cs->cs_defspeed = 9600;	/* XXX */
476 
477 	/* Clear the master interrupt enable. */
478 	zs_write_reg(cs, 9, 0);
479 
480 	/* Reset the whole SCC chip. */
481 	zs_write_reg(cs, 9, ZSWR9_HARD_RESET);
482 
483 	/* Copy "pending" to "current" and H/W. */
484 	zs_loadchannelregs(cs);
485 
486 	/* Point the console at the SCC. */
487 	cn_tab = &zscons;
488 }
489