pl030_rtc.c revision 1.6 1 /* $NetBSD: pl030_rtc.c,v 1.6 2003/07/15 00:24:59 lukem Exp $ */
2
3 /*
4 * Copyright (c) 2001 ARM Ltd
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 company may not be used to endorse or promote
16 * products derived from this software without specific prior written
17 * permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
20 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
21 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
22 * IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
23 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
24 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
25 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32 /* Include header files */
33
34 #include <sys/cdefs.h>
35 __KERNEL_RCSID(0, "$NetBSD: pl030_rtc.c,v 1.6 2003/07/15 00:24:59 lukem Exp $");
36
37 #include <sys/types.h>
38 #include <sys/param.h>
39 #include <sys/systm.h>
40 #include <sys/kernel.h>
41 #include <sys/time.h>
42 #include <sys/device.h>
43
44 #include <arm/cpufunc.h>
45 #include <machine/intr.h>
46 #include <evbarm/ifpga/ifpgavar.h>
47 #include <evbarm/ifpga/ifpgamem.h>
48 #include <evbarm/ifpga/ifpgareg.h>
49
50 #define PL030_RTC_SIZE 0x14
51
52 struct plrtc_softc {
53 struct device sc_dev;
54 bus_space_tag_t sc_iot;
55 bus_space_handle_t sc_ioh;
56 };
57
58 static int plrtc_probe (struct device *, struct cfdata *, void *);
59 static void plrtc_attach (struct device *, struct device *, void *);
60
61 CFATTACH_DECL(plrtc, sizeof(struct plrtc_softc),
62 plrtc_probe, plrtc_attach, NULL, NULL);
63
64 /* Remember our handle, since it isn't passed in by inittodr and
65 resettodr. */
66 static struct plrtc_softc *plrtc_sc;
67
68 static int timeset = 0;
69
70 static int
71 plrtc_probe(struct device *parent, struct cfdata *cf, void *aux)
72 {
73 return 1;
74 }
75
76 static void
77 plrtc_attach(struct device *parent, struct device *self, void *aux)
78 {
79 struct ifpga_attach_args *ifa = aux;
80 struct plrtc_softc *sc = (struct plrtc_softc *)self;
81
82 sc->sc_iot = ifa->ifa_iot;
83 if (bus_space_map(ifa->ifa_iot, ifa->ifa_addr, PL030_RTC_SIZE, 0,
84 &sc->sc_ioh)) {
85 printf("%s: unable to map device\n", sc->sc_dev.dv_xname);
86 return;
87 }
88
89 plrtc_sc = sc;
90
91 printf("\n");
92 }
93
94 void
95 inittodr(time_t base)
96 {
97 time_t rtc_time;
98 struct plrtc_softc *sc = plrtc_sc;
99
100 if (sc == NULL)
101 panic("RTC not attached");
102
103 /* Default to the suggested time, but replace that with one from the
104 RTC if it seems more sensible. */
105 rtc_time = bus_space_read_4(sc->sc_iot, sc->sc_ioh, IFPGA_RTC_DR);
106
107 time.tv_usec = 0;
108 time.tv_sec = rtc_time;
109
110 timeset = 1;
111
112 if (base > rtc_time) {
113 printf("inittodr: rtc value suspect, ignoring it.\n");
114 time.tv_usec = 0;
115 time.tv_sec = base;
116 return;
117 }
118 }
119
120 void
121 resettodr()
122 {
123 struct plrtc_softc *sc = plrtc_sc;
124
125 /* The time hasn't been set yet, so avoid writing a dubious value
126 to the RTC. */
127 if (!timeset)
128 return;
129
130 bus_space_write_4(sc->sc_iot, sc->sc_ioh, IFPGA_RTC_LR, time.tv_sec);
131 }
132