xref: /netbsd-src/sys/arch/sparc/dev/rtc.c (revision 76c7fc5f6b13ed0b1508e6b313e88e59977ed78e)
1 /*	$NetBSD: rtc.c,v 1.19 2019/11/10 21:16:32 chs Exp $ */
2 
3 /*
4  * Copyright (c) 2001 Valeriy E. Ushakov
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. The name of the author may not be used to endorse or promote products
16  *    derived from this software without specific prior written permission
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28  */
29 
30 /*
31  * `rtc' is a DS1287A (== MC146818A) time-of-day clock at EBus.
32  * In Krups it's not used to store idprom so this driver doesn't
33  * support it.  Don't know about other ms-IIep systems.
34  */
35 
36 #include <sys/cdefs.h>
37 __KERNEL_RCSID(0, "$NetBSD: rtc.c,v 1.19 2019/11/10 21:16:32 chs Exp $");
38 
39 #include <sys/param.h>
40 #include <sys/kernel.h>
41 #include <sys/device.h>
42 #include <sys/malloc.h>
43 #include <sys/systm.h>
44 #ifdef GPROF
45 #include <sys/gmon.h>
46 #endif
47 
48 #include <sys/bus.h>
49 #include <machine/autoconf.h>
50 
51 #include <dev/clock_subr.h>
52 #include <dev/ic/mc146818reg.h>
53 
54 #include <dev/ebus/ebusreg.h>
55 #include <dev/ebus/ebusvar.h>
56 
57 struct rtc_ebus_softc {
58 	bus_space_tag_t		sc_bt;	/* parent bus tag */
59 	bus_space_handle_t	sc_bh;	/* handle for registers */
60 };
61 
62 static int	rtcmatch_ebus(device_t, cfdata_t, void *);
63 static void	rtcattach_ebus(device_t, device_t, void *);
64 
65 CFATTACH_DECL_NEW(rtc_ebus, sizeof(struct rtc_ebus_softc),
66     rtcmatch_ebus, rtcattach_ebus, NULL, NULL);
67 
68 /* XXX: global TOD clock handle (sparc/clock.c) */
69 extern todr_chip_handle_t todr_handle;
70 
71 /* todr(9) methods */
72 static int rtc_gettime(todr_chip_handle_t, struct timeval *);
73 static int rtc_settime(todr_chip_handle_t, struct timeval *);
74 
75 int rtc_auto_century_adjust = 1; /* XXX: do we ever want not to? */
76 
77 
78 /*
79  * MD read/write functions declared in mc146818reg.h
80  */
81 #define	RTC_ADDR	0
82 #define	RTC_DATA	1
83 
84 u_int
85 mc146818_read(void *cookie, u_int reg)
86 {
87 	struct rtc_ebus_softc *sc = cookie;
88 
89 	bus_space_write_1(sc->sc_bt, sc->sc_bh, RTC_ADDR, reg);
90 	return (bus_space_read_1(sc->sc_bt, sc->sc_bh, RTC_DATA));
91 }
92 
93 void
94 mc146818_write(void *cookie, u_int reg, u_int datum)
95 {
96 	struct rtc_ebus_softc *sc = cookie;
97 
98 	bus_space_write_1(sc->sc_bt, sc->sc_bh, RTC_ADDR, reg);
99 	bus_space_write_1(sc->sc_bt, sc->sc_bh, RTC_DATA, datum);
100 }
101 
102 
103 static int
104 rtcmatch_ebus(device_t parent, cfdata_t cf, void *aux)
105 {
106 	struct ebus_attach_args *ea = aux;
107 
108 	return (strcmp(cf->cf_name, ea->ea_name) == 0);
109 }
110 
111 static void
112 rtcattach_ebus(device_t parent, device_t self, void *aux)
113 {
114 	struct rtc_ebus_softc *sc = device_private(self);
115 	struct ebus_attach_args *ea = aux;
116 	todr_chip_handle_t handle;
117 
118 	sc->sc_bt = ea->ea_bustag;
119 	if (bus_space_map(sc->sc_bt, EBUS_ADDR_FROM_REG(&ea->ea_reg[0]),
120 			  ea->ea_reg[0].size, 0, &sc->sc_bh) != 0)
121 	{
122 		printf(": unable to map registers\n");
123 		return;
124 	}
125 
126 	/* XXX: no "model" property in Krups */
127 	printf(": time-of-day clock\n");
128 
129 	/*
130 	 * Turn interrupts off (clear MC_REGB_?IE bits), just in case
131 	 * (although they shouldn't be wired to an interrupt
132 	 * controller on sparcs).
133 	 */
134 	mc146818_write(sc, MC_REGB, MC_REGB_BINARY | MC_REGB_24HR);
135 
136 	/* setup our todr_handle */
137 	handle = malloc(ALIGN(sizeof(struct todr_chip_handle)),
138 			M_DEVBUF, M_WAITOK);
139 	handle->cookie = sc;
140 	handle->bus_cookie = NULL; /* unused */
141 	handle->todr_gettime = rtc_gettime;
142 	handle->todr_settime = rtc_settime;
143 	handle->todr_setwen = NULL; /* not necessary, no idprom to protect */
144 
145 	todr_attach(handle);
146 }
147 
148 
149 /*
150  * Get time-of-day and convert to a `struct timeval'
151  * Return 0 on success; an error number otherwise.
152  */
153 static int
154 rtc_gettime(todr_chip_handle_t handle, struct timeval *tv)
155 {
156 	struct rtc_ebus_softc *sc = handle->cookie;
157 	struct clock_ymdhms dt;
158 	u_int year;
159 
160 	/* update in progress; spin loop */
161 	while (mc146818_read(sc, MC_REGA) & MC_REGA_UIP)
162 		continue;
163 
164 	/* stop updates (XXX: do we need that???) */
165 	mc146818_write(sc, MC_REGB,
166 		       (mc146818_read(sc, MC_REGB) | MC_REGB_SET));
167 
168 	/* read time */
169 	dt.dt_sec  = mc146818_read(sc, MC_SEC);
170 	dt.dt_min  = mc146818_read(sc, MC_MIN);
171 	dt.dt_hour = mc146818_read(sc, MC_HOUR);
172 	dt.dt_day  = mc146818_read(sc, MC_DOM);
173 	dt.dt_mon  = mc146818_read(sc, MC_MONTH);
174 	year       = mc146818_read(sc, MC_YEAR);
175 
176 	/* reenable updates */
177 	mc146818_write(sc, MC_REGB,
178 		       (mc146818_read(sc, MC_REGB) & ~MC_REGB_SET));
179 
180 	/* year in the century 0..99: adjust to AD */
181 	year += 1900;
182 	if (year < POSIX_BASE_YEAR && rtc_auto_century_adjust != 0)
183 		year += 100;
184 	dt.dt_year = year;
185 
186 	/* simple sanity checks */
187 	if (dt.dt_mon > 12 || dt.dt_day > 31
188 	    || dt.dt_hour >= 24 || dt.dt_min >= 60 || dt.dt_sec >= 60)
189 		return (ERANGE);
190 
191 	tv->tv_sec = clock_ymdhms_to_secs(&dt);
192 	tv->tv_usec = 0;
193 	return (0);
194 }
195 
196 /*
197  * Set the time-of-day clock based on the value of the `struct timeval' arg.
198  * Return 0 on success; an error number otherwise.
199  */
200 static int
201 rtc_settime(todr_chip_handle_t handle, struct timeval *tv)
202 {
203 	struct rtc_ebus_softc *sc = handle->cookie;
204 	struct clock_ymdhms dt;
205 	u_int year;
206 
207 	clock_secs_to_ymdhms(tv->tv_sec, &dt);
208 
209 	year = dt.dt_year - 1900;
210 	if (year >= 100 && rtc_auto_century_adjust != 0)
211 		year -= 100;
212 
213 	/* stop updates */
214 	mc146818_write(sc, MC_REGB,
215 		       (mc146818_read(sc, MC_REGB) | MC_REGB_SET));
216 
217 	mc146818_write(sc, MC_SEC,   dt.dt_sec);
218 	mc146818_write(sc, MC_MIN,   dt.dt_min);
219 	mc146818_write(sc, MC_HOUR,  dt.dt_hour);
220 	mc146818_write(sc, MC_DOW,   dt.dt_wday + 1);
221 	mc146818_write(sc, MC_DOM,   dt.dt_day);
222 	mc146818_write(sc, MC_MONTH, dt.dt_mon);
223 	mc146818_write(sc, MC_YEAR,  year);
224 
225 	/* reenable updates */
226 	mc146818_write(sc, MC_REGB,
227 		       (mc146818_read(sc, MC_REGB) & ~MC_REGB_SET));
228 	return (0);
229 }
230