1 /* $NetBSD: rtc.c,v 1.21 2023/12/20 05:33:18 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 1.21 2023/12/20 05:33:18 thorpej Exp $");
38
39 #include <sys/param.h>
40 #include <sys/kernel.h>
41 #include <sys/device.h>
42 #include <sys/systm.h>
43 #ifdef GPROF
44 #include <sys/gmon.h>
45 #endif
46
47 #include <sys/bus.h>
48 #include <machine/autoconf.h>
49
50 #include <dev/clock_subr.h>
51 #include <dev/ic/mc146818reg.h>
52
53 #include <dev/ebus/ebusreg.h>
54 #include <dev/ebus/ebusvar.h>
55
56 struct rtc_ebus_softc {
57 bus_space_tag_t sc_bt; /* parent bus tag */
58 bus_space_handle_t sc_bh; /* handle for registers */
59 struct todr_chip_handle sc_todr;/* TODR handle */
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 /* todr(9) methods */
69 static int rtc_gettime_ymdhms(todr_chip_handle_t, struct clock_ymdhms *);
70 static int rtc_settime_ymdhms(todr_chip_handle_t, struct clock_ymdhms *);
71
72 int rtc_auto_century_adjust = 1; /* XXX: do we ever want not to? */
73
74 /*
75 * MD read/write functions declared in mc146818reg.h
76 */
77 #define RTC_ADDR 0
78 #define RTC_DATA 1
79
80 u_int
mc146818_read(void * cookie,u_int reg)81 mc146818_read(void *cookie, u_int reg)
82 {
83 struct rtc_ebus_softc *sc = cookie;
84
85 bus_space_write_1(sc->sc_bt, sc->sc_bh, RTC_ADDR, reg);
86 return (bus_space_read_1(sc->sc_bt, sc->sc_bh, RTC_DATA));
87 }
88
89 void
mc146818_write(void * cookie,u_int reg,u_int datum)90 mc146818_write(void *cookie, u_int reg, u_int datum)
91 {
92 struct rtc_ebus_softc *sc = cookie;
93
94 bus_space_write_1(sc->sc_bt, sc->sc_bh, RTC_ADDR, reg);
95 bus_space_write_1(sc->sc_bt, sc->sc_bh, RTC_DATA, datum);
96 }
97
98
99 static int
rtcmatch_ebus(device_t parent,cfdata_t cf,void * aux)100 rtcmatch_ebus(device_t parent, cfdata_t cf, void *aux)
101 {
102 struct ebus_attach_args *ea = aux;
103
104 return (strcmp(cf->cf_name, ea->ea_name) == 0);
105 }
106
107 static void
rtcattach_ebus(device_t parent,device_t self,void * aux)108 rtcattach_ebus(device_t parent, device_t self, void *aux)
109 {
110 struct rtc_ebus_softc *sc = device_private(self);
111 struct ebus_attach_args *ea = aux;
112 todr_chip_handle_t handle;
113
114 sc->sc_bt = ea->ea_bustag;
115 if (bus_space_map(sc->sc_bt, EBUS_ADDR_FROM_REG(&ea->ea_reg[0]),
116 ea->ea_reg[0].size, 0, &sc->sc_bh) != 0)
117 {
118 printf(": unable to map registers\n");
119 return;
120 }
121
122 /* XXX: no "model" property in Krups */
123 printf(": time-of-day clock\n");
124
125 /*
126 * Turn interrupts off (clear MC_REGB_?IE bits), just in case
127 * (although they shouldn't be wired to an interrupt
128 * controller on sparcs).
129 */
130 mc146818_write(sc, MC_REGB, MC_REGB_BINARY | MC_REGB_24HR);
131
132 /* setup our todr_handle */
133 handle = &sc->sc_todr;
134 handle->cookie = sc;
135 handle->bus_cookie = NULL; /* unused */
136 handle->todr_gettime = NULL;
137 handle->todr_settime = NULL;
138 handle->todr_gettime_ymdhms = rtc_gettime_ymdhms;
139 handle->todr_settime_ymdhms = rtc_settime_ymdhms;
140 handle->todr_setwen = NULL; /* not necessary, no idprom to protect */
141
142 todr_attach(handle);
143 }
144
145
146 static int
rtc_gettime_ymdhms(todr_chip_handle_t handle,struct clock_ymdhms * dt)147 rtc_gettime_ymdhms(todr_chip_handle_t handle, struct clock_ymdhms *dt)
148 {
149 struct rtc_ebus_softc *sc = handle->cookie;
150 u_int year;
151
152 /* update in progress; spin loop */
153 while (mc146818_read(sc, MC_REGA) & MC_REGA_UIP)
154 continue;
155
156 /* stop updates (XXX: do we need that???) */
157 mc146818_write(sc, MC_REGB,
158 (mc146818_read(sc, MC_REGB) | MC_REGB_SET));
159
160 /* read time */
161 dt->dt_sec = mc146818_read(sc, MC_SEC);
162 dt->dt_min = mc146818_read(sc, MC_MIN);
163 dt->dt_hour = mc146818_read(sc, MC_HOUR);
164 dt->dt_day = mc146818_read(sc, MC_DOM);
165 dt->dt_mon = mc146818_read(sc, MC_MONTH);
166 year = mc146818_read(sc, MC_YEAR);
167
168 /* reenable updates */
169 mc146818_write(sc, MC_REGB,
170 (mc146818_read(sc, MC_REGB) & ~MC_REGB_SET));
171
172 /* year in the century 0..99: adjust to AD */
173 year += 1900;
174 if (year < POSIX_BASE_YEAR && rtc_auto_century_adjust != 0)
175 year += 100;
176 dt->dt_year = year;
177
178 return (0);
179 }
180
181 static int
rtc_settime_ymdhms(todr_chip_handle_t handle,struct clock_ymdhms * dt)182 rtc_settime_ymdhms(todr_chip_handle_t handle, struct clock_ymdhms *dt)
183 {
184 struct rtc_ebus_softc *sc = handle->cookie;
185 u_int year;
186
187 year = dt->dt_year - 1900;
188 if (year >= 100 && rtc_auto_century_adjust != 0)
189 year -= 100;
190
191 /* stop updates */
192 mc146818_write(sc, MC_REGB,
193 (mc146818_read(sc, MC_REGB) | MC_REGB_SET));
194
195 mc146818_write(sc, MC_SEC, dt->dt_sec);
196 mc146818_write(sc, MC_MIN, dt->dt_min);
197 mc146818_write(sc, MC_HOUR, dt->dt_hour);
198 mc146818_write(sc, MC_DOW, dt->dt_wday + 1);
199 mc146818_write(sc, MC_DOM, dt->dt_day);
200 mc146818_write(sc, MC_MONTH, dt->dt_mon);
201 mc146818_write(sc, MC_YEAR, year);
202
203 /* reenable updates */
204 mc146818_write(sc, MC_REGB,
205 (mc146818_read(sc, MC_REGB) & ~MC_REGB_SET));
206 return (0);
207 }
208