xref: /netbsd-src/sys/arch/sparc/dev/rtc.c (revision 53b02e147d4ed531c0d2a5ca9b3e8026ba3e99b5)
1 /*	$NetBSD: rtc.c,v 1.20 2020/01/02 22:32:20 thorpej 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 1.20 2020/01/02 22:32:20 thorpej 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 	struct todr_chip_handle	sc_todr;/* TODR handle */
61 };
62 
63 static int	rtcmatch_ebus(device_t, cfdata_t, void *);
64 static void	rtcattach_ebus(device_t, device_t, void *);
65 
66 CFATTACH_DECL_NEW(rtc_ebus, sizeof(struct rtc_ebus_softc),
67     rtcmatch_ebus, rtcattach_ebus, NULL, NULL);
68 
69 /* todr(9) methods */
70 static int rtc_gettime_ymdhms(todr_chip_handle_t, struct clock_ymdhms *);
71 static int rtc_settime_ymdhms(todr_chip_handle_t, struct clock_ymdhms *);
72 
73 int rtc_auto_century_adjust = 1; /* XXX: do we ever want not to? */
74 
75 /*
76  * MD read/write functions declared in mc146818reg.h
77  */
78 #define	RTC_ADDR	0
79 #define	RTC_DATA	1
80 
81 u_int
82 mc146818_read(void *cookie, u_int reg)
83 {
84 	struct rtc_ebus_softc *sc = cookie;
85 
86 	bus_space_write_1(sc->sc_bt, sc->sc_bh, RTC_ADDR, reg);
87 	return (bus_space_read_1(sc->sc_bt, sc->sc_bh, RTC_DATA));
88 }
89 
90 void
91 mc146818_write(void *cookie, u_int reg, u_int datum)
92 {
93 	struct rtc_ebus_softc *sc = cookie;
94 
95 	bus_space_write_1(sc->sc_bt, sc->sc_bh, RTC_ADDR, reg);
96 	bus_space_write_1(sc->sc_bt, sc->sc_bh, RTC_DATA, datum);
97 }
98 
99 
100 static int
101 rtcmatch_ebus(device_t parent, cfdata_t cf, void *aux)
102 {
103 	struct ebus_attach_args *ea = aux;
104 
105 	return (strcmp(cf->cf_name, ea->ea_name) == 0);
106 }
107 
108 static void
109 rtcattach_ebus(device_t parent, device_t self, void *aux)
110 {
111 	struct rtc_ebus_softc *sc = device_private(self);
112 	struct ebus_attach_args *ea = aux;
113 	todr_chip_handle_t handle;
114 
115 	sc->sc_bt = ea->ea_bustag;
116 	if (bus_space_map(sc->sc_bt, EBUS_ADDR_FROM_REG(&ea->ea_reg[0]),
117 			  ea->ea_reg[0].size, 0, &sc->sc_bh) != 0)
118 	{
119 		printf(": unable to map registers\n");
120 		return;
121 	}
122 
123 	/* XXX: no "model" property in Krups */
124 	printf(": time-of-day clock\n");
125 
126 	/*
127 	 * Turn interrupts off (clear MC_REGB_?IE bits), just in case
128 	 * (although they shouldn't be wired to an interrupt
129 	 * controller on sparcs).
130 	 */
131 	mc146818_write(sc, MC_REGB, MC_REGB_BINARY | MC_REGB_24HR);
132 
133 	/* setup our todr_handle */
134 	handle = &sc->sc_todr;
135 	handle->cookie = sc;
136 	handle->bus_cookie = NULL; /* unused */
137 	handle->todr_gettime = NULL;
138 	handle->todr_settime = NULL;
139 	handle->todr_gettime_ymdhms = rtc_gettime_ymdhms;
140 	handle->todr_settime_ymdhms = rtc_settime_ymdhms;
141 	handle->todr_setwen = NULL; /* not necessary, no idprom to protect */
142 
143 	todr_attach(handle);
144 }
145 
146 
147 static int
148 rtc_gettime_ymdhms(todr_chip_handle_t handle, struct clock_ymdhms *dt)
149 {
150 	struct rtc_ebus_softc *sc = handle->cookie;
151 	u_int year;
152 
153 	/* update in progress; spin loop */
154 	while (mc146818_read(sc, MC_REGA) & MC_REGA_UIP)
155 		continue;
156 
157 	/* stop updates (XXX: do we need that???) */
158 	mc146818_write(sc, MC_REGB,
159 		       (mc146818_read(sc, MC_REGB) | MC_REGB_SET));
160 
161 	/* read time */
162 	dt->dt_sec  = mc146818_read(sc, MC_SEC);
163 	dt->dt_min  = mc146818_read(sc, MC_MIN);
164 	dt->dt_hour = mc146818_read(sc, MC_HOUR);
165 	dt->dt_day  = mc146818_read(sc, MC_DOM);
166 	dt->dt_mon  = mc146818_read(sc, MC_MONTH);
167 	year        = mc146818_read(sc, MC_YEAR);
168 
169 	/* reenable updates */
170 	mc146818_write(sc, MC_REGB,
171 		       (mc146818_read(sc, MC_REGB) & ~MC_REGB_SET));
172 
173 	/* year in the century 0..99: adjust to AD */
174 	year += 1900;
175 	if (year < POSIX_BASE_YEAR && rtc_auto_century_adjust != 0)
176 		year += 100;
177 	dt->dt_year = year;
178 
179 	return (0);
180 }
181 
182 static int
183 rtc_settime_ymdhms(todr_chip_handle_t handle, struct clock_ymdhms *dt)
184 {
185 	struct rtc_ebus_softc *sc = handle->cookie;
186 	u_int year;
187 
188 	year = dt->dt_year - 1900;
189 	if (year >= 100 && rtc_auto_century_adjust != 0)
190 		year -= 100;
191 
192 	/* stop updates */
193 	mc146818_write(sc, MC_REGB,
194 		       (mc146818_read(sc, MC_REGB) | MC_REGB_SET));
195 
196 	mc146818_write(sc, MC_SEC,   dt->dt_sec);
197 	mc146818_write(sc, MC_MIN,   dt->dt_min);
198 	mc146818_write(sc, MC_HOUR,  dt->dt_hour);
199 	mc146818_write(sc, MC_DOW,   dt->dt_wday + 1);
200 	mc146818_write(sc, MC_DOM,   dt->dt_day);
201 	mc146818_write(sc, MC_MONTH, dt->dt_mon);
202 	mc146818_write(sc, MC_YEAR,  year);
203 
204 	/* reenable updates */
205 	mc146818_write(sc, MC_REGB,
206 		       (mc146818_read(sc, MC_REGB) & ~MC_REGB_SET));
207 	return (0);
208 }
209