xref: /netbsd-src/sys/arch/ews4800mips/dev/zs.c (revision 8b0f9554ff8762542c4defc4f70e1eb76fb508fa)
1 /*	$NetBSD: zs.c,v 1.3 2007/11/26 23:29:37 ad Exp $	*/
2 
3 /*-
4  * Copyright (c) 1996, 2005 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 1.3 2007/11/26 23:29:37 ad Exp $");
48 
49 #include "opt_ddb.h"
50 
51 #include <sys/param.h>
52 #include <sys/device.h>
53 #include <sys/tty.h>
54 #include <sys/systm.h>
55 #include <sys/intr.h>
56 
57 #include <machine/z8530var.h>
58 #include <dev/ic/z8530reg.h>
59 
60 #include "ioconf.h"
61 
62 /* console status for consinit() */
63 static struct zs_chanstate zs_conscs_store;
64 struct zs_chanstate *zs_conscs = &zs_conscs_store;
65 void *zs_consaddr;
66 
67 /*
68  * Some warts needed by z8530tty.c -
69  * The default parity REALLY needs to be the same as the PROM uses,
70  * or you can not see messages done with printf during boot-up...
71  */
72 int zs_def_cflag = (CREAD | CS8 | HUPCL);
73 
74 int
75 zs_print(void *aux, const char *name)
76 {
77 	struct zsc_attach_args *args = aux;
78 
79 	if (name != NULL)
80 		aprint_normal("%s: ", name);
81 
82 	if (args->channel != -1)
83 		aprint_normal(" channel %d", args->channel);
84 
85 	return UNCONF;
86 }
87 
88 int
89 zshard(void *arg)
90 {
91 	struct zsc_softc *zsc;
92 	int rval;
93 
94 	zsc = arg;
95 	rval = zsc_intr_hard(zsc);
96 	if (zsc->zsc_cs[0]->cs_softreq || zsc->zsc_cs[1]->cs_softreq)
97 		softint_schedule(zsc->zsc_si);
98 
99 	return rval;
100 }
101 
102 /*
103  * Compute the current baud rate given a ZS channel.
104  */
105 int
106 zs_get_speed(struct zs_chanstate *cs)
107 {
108 	int tconst;
109 
110 	tconst = zs_read_reg(cs, 12);
111 	tconst |= zs_read_reg(cs, 13) << 8;
112 	return TCONST_TO_BPS(cs->cs_brg_clk, tconst);
113 }
114 
115 /*
116  * MD functions for setting the baud rate and control modes.
117  */
118 int
119 zs_set_speed(struct zs_chanstate *cs, int bps)
120 {
121 	int tconst, real_bps;
122 
123 	if (bps == 0)
124 		return 0;
125 
126 #ifdef	DIAGNOSTIC
127 	if (cs->cs_brg_clk == 0)
128 		panic("zs_set_speed");
129 #endif
130 
131 	tconst = BPS_TO_TCONST(cs->cs_brg_clk, bps);
132 	if (tconst < 0)
133 		return EINVAL;
134 
135 	/* Convert back to make sure we can do it. */
136 	real_bps = TCONST_TO_BPS(cs->cs_brg_clk, tconst);
137 
138 	/* XXX - Allow some tolerance here? */
139 	if (real_bps != bps)
140 		return EINVAL;
141 
142 	cs->cs_preg[12] = tconst;
143 	cs->cs_preg[13] = tconst >> 8;
144 
145 	/* Caller will stuff the pending registers. */
146 	return 0;
147 }
148 
149 int
150 zs_set_modes(struct zs_chanstate *cs, int cflag)
151 {
152 	int s;
153 
154 	/*
155 	 * Output hardware flow control on the chip is horrendous:
156 	 * if carrier detect drops, the receiver is disabled, and if
157 	 * CTS drops, the transmitter is stoped IN MID CHARACTER!
158 	 * Therefore, NEVER set the HFC bit, and instead use the
159 	 * status interrupt to detect CTS changes.
160 	 */
161 	s = splserial();
162 	cs->cs_rr0_pps = 0;
163 	if ((cflag & (CLOCAL | MDMBUF)) != 0) {
164 		cs->cs_rr0_dcd = 0;
165 		if ((cflag & MDMBUF) == 0)
166 			cs->cs_rr0_pps = ZSRR0_DCD;
167 	} else
168 		cs->cs_rr0_dcd = ZSRR0_DCD;
169 	if ((cflag & CRTSCTS) != 0) {
170 		cs->cs_wr5_dtr = ZSWR5_DTR;
171 		cs->cs_wr5_rts = ZSWR5_RTS;
172 		cs->cs_rr0_cts = ZSRR0_CTS;
173 	} else if ((cflag & MDMBUF) != 0) {
174 		cs->cs_wr5_dtr = 0;
175 		cs->cs_wr5_rts = ZSWR5_DTR;
176 		cs->cs_rr0_cts = ZSRR0_DCD;
177 	} else {
178 		cs->cs_wr5_dtr = ZSWR5_DTR | ZSWR5_RTS;
179 		cs->cs_wr5_rts = 0;
180 		cs->cs_rr0_cts = 0;
181 	}
182 	splx(s);
183 
184 	/* Caller will stuff the pending registers. */
185 	return 0;
186 }
187 
188 /*
189  * Read or write the chip with suitable delays.
190  */
191 uint8_t
192 zs_read_reg(struct zs_chanstate *cs, uint8_t reg)
193 {
194 	uint8_t val;
195 
196 	*cs->cs_reg_csr = reg;
197 
198 	val = *cs->cs_reg_csr;
199 
200 	return val;
201 }
202 
203 void
204 zs_write_reg(struct zs_chanstate *cs, uint8_t reg, uint8_t val)
205 {
206 
207 	*cs->cs_reg_csr = reg;
208 
209 	*cs->cs_reg_csr = val;
210 
211 }
212 
213 uint8_t
214 zs_read_csr(struct zs_chanstate *cs)
215 {
216 	uint8_t val;
217 
218 	val = *cs->cs_reg_csr;
219 
220 	return val;
221 }
222 
223 void
224 zs_write_csr(struct zs_chanstate *cs, uint8_t val)
225 {
226 
227 	*cs->cs_reg_csr = val;
228 
229 }
230 
231 uint8_t
232 zs_read_data(struct zs_chanstate *cs)
233 {
234 	uint8_t val;
235 
236 	val = *cs->cs_reg_data;
237 
238 	return val;
239 }
240 
241 void
242 zs_write_data(struct zs_chanstate *cs, uint8_t val)
243 {
244 
245 	*cs->cs_reg_data = val;
246 }
247 
248 void
249 zs_abort(struct zs_chanstate *cs)
250 {
251 
252 #ifdef DDB
253 	Debugger();
254 #endif
255 }
256 
257 /*
258  * Polled input char.
259  */
260 int
261 zs_getc(void *arg)
262 {
263 	struct zs_chanstate *cs = arg;
264 	int s, c, rr0;
265 
266 	s = splhigh();
267 	/* Wait for a character to arrive. */
268 	do {
269 		rr0 = *cs->cs_reg_csr;
270 		ZS_DELAY();
271 	} while ((rr0 & ZSRR0_RX_READY) == 0);
272 
273 	c = *cs->cs_reg_data;
274 	ZS_DELAY();
275 	splx(s);
276 
277 	/*
278 	 * This could be used by the kd driver to read scan codes,
279 	 * so don't translate '\r' ==> '\n' here...
280 	 */
281 	return c;
282 }
283 
284 /*
285  * Polled output char.
286  */
287 void
288 zs_putc(void *arg, int c)
289 {
290 	struct zs_chanstate *cs = arg;
291 	int s, rr0;
292 
293 	s = splhigh();
294 	/* Wait for transmitter to become ready. */
295 	do {
296 		rr0 = *cs->cs_reg_csr;
297 		ZS_DELAY();
298 	} while ((rr0 & ZSRR0_TX_READY) == 0);
299 
300 	*cs->cs_reg_data = c;
301 	ZS_DELAY();
302 	splx(s);
303 }
304 
305 int
306 zscngetc(dev_t dev)
307 {
308 
309 	return zs_getc((void *)zs_conscs);
310 }
311 
312 void
313 zscnputc(dev_t dev, int c)
314 {
315 
316 	zs_putc((void *)zs_conscs, c);
317 }
318