xref: /openbsd/sys/arch/loongson/dev/mcclock.c (revision a877a4f7)
1 /*	$OpenBSD: mcclock.c,v 1.6 2022/10/15 14:58:54 jsg Exp $	*/
2 /*	$NetBSD: mcclock.c,v 1.4 1996/10/13 02:59:41 christos Exp $	*/
3 
4 /*
5  * Copyright (c) 1994, 1995, 1996 Carnegie-Mellon University.
6  * All rights reserved.
7  *
8  * Author: Chris G. Demetriou
9  *
10  * Permission to use, copy, modify and distribute this software and
11  * its documentation is hereby granted, provided that both the copyright
12  * notice and this permission notice appear in all copies of the
13  * software, derivative works or modified versions, and any portions
14  * thereof, and that both notices appear in supporting documentation.
15  *
16  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
17  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
18  * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
19  *
20  * Carnegie Mellon requests users of this software to return to
21  *
22  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
23  *  School of Computer Science
24  *  Carnegie Mellon University
25  *  Pittsburgh PA 15213-3890
26  *
27  * any improvements or extensions that they make and grant Carnegie the
28  * rights to redistribute these changes.
29  */
30 
31 #include <sys/param.h>
32 #include <sys/kernel.h>
33 #include <sys/systm.h>
34 #include <sys/device.h>
35 
36 #include <dev/clock_subr.h>
37 #include <dev/ic/mc146818reg.h>
38 
39 #include <loongson/dev/mcclockvar.h>
40 
41 struct cfdriver mcclock_cd = {
42 	NULL, "mcclock", DV_DULL,
43 };
44 
45 int	mcclock_gettime(struct todr_chip_handle *, struct timeval *);
46 int	mcclock_settime(struct todr_chip_handle *, struct timeval *);
47 
48 #define	mc146818_write(dev, reg, datum)					\
49 	    (*(dev)->sc_busfns->mc_bf_write)(dev, reg, datum)
50 #define	mc146818_read(dev, reg)						\
51 	    (*(dev)->sc_busfns->mc_bf_read)(dev, reg)
52 
53 void
mcclock_attach(struct mcclock_softc * sc,const struct mcclock_busfns * busfns)54 mcclock_attach(struct mcclock_softc *sc, const struct mcclock_busfns *busfns)
55 {
56 
57 	printf(": mc146818 or compatible\n");
58 
59 	sc->sc_busfns = busfns;
60 
61 	/* Turn interrupts off, just in case. */
62 	mc146818_write(sc, MC_REGB, MC_REGB_BINARY | MC_REGB_24HR);
63 	mc146818_write(sc, MC_REGA, MC_BASE_32_KHz | MC_RATE_NONE);
64 
65 	sc->sc_todr.cookie = sc;
66 	sc->sc_todr.todr_gettime = mcclock_gettime;
67 	sc->sc_todr.todr_settime = mcclock_settime;
68 	sc->sc_todr.todr_quality = 0;
69 	todr_attach(&sc->sc_todr);
70 }
71 
72 /*
73  * Get the time of day, based on the clock's value and/or the base value.
74  */
75 int
mcclock_gettime(struct todr_chip_handle * handle,struct timeval * tv)76 mcclock_gettime(struct todr_chip_handle *handle, struct timeval *tv)
77 {
78 	struct clock_ymdhms dt;
79 	struct mcclock_softc *sc = handle->cookie;
80 	mc_todregs regs;
81 	int s;
82 
83 	s = splclock();
84 	MC146818_GETTOD(sc, &regs)
85 	splx(s);
86 
87 	dt.dt_sec = regs[MC_SEC];
88 	dt.dt_min = regs[MC_MIN];
89 	dt.dt_hour = regs[MC_HOUR];
90 	dt.dt_day = regs[MC_DOM];
91 	dt.dt_mon = regs[MC_MONTH];
92 	dt.dt_year = regs[MC_YEAR] + 2000;
93 
94 	tv->tv_sec = clock_ymdhms_to_secs(&dt);
95 	tv->tv_usec = 0;
96 	return 0;
97 }
98 
99 /*
100  * Reset the TODR based on the time value.
101  */
102 int
mcclock_settime(struct todr_chip_handle * handle,struct timeval * tv)103 mcclock_settime(struct todr_chip_handle *handle, struct timeval *tv)
104 {
105 	struct clock_ymdhms dt;
106 	struct mcclock_softc *sc = handle->cookie;
107 	mc_todregs regs;
108 	int s;
109 
110 	clock_secs_to_ymdhms(tv->tv_sec, &dt);
111 
112 	s = splclock();
113 	MC146818_GETTOD(sc, &regs);
114 	splx(s);
115 
116 	regs[MC_SEC] = dt.dt_sec;
117 	regs[MC_MIN] = dt.dt_min;
118 	regs[MC_HOUR] = dt.dt_hour;
119 	regs[MC_DOW] = dt.dt_wday + 1;
120 	regs[MC_DOM] = dt.dt_day;
121 	regs[MC_MONTH] = dt.dt_mon;
122 	regs[MC_YEAR] = dt.dt_year % 100;
123 
124 	s = splclock();
125 	MC146818_PUTTOD(sc, &regs);
126 	splx(s);
127 
128 	return 0;
129 }
130