1/*	$NetBSD: tsrtc.c,v 1.6 2008/04/04 09:33:07 tsutsui Exp $	*/
2
3/*
4 * Copyright (c) 1995, 1996 Carnegie-Mellon University.
5 * All rights reserved.
6 *
7 * Author: Chris G. Demetriou
8 *
9 * Permission to use, copy, modify and distribute this software and
10 * its documentation is hereby granted, provided that both the copyright
11 * notice and this permission notice appear in all copies of the
12 * software, derivative works or modified versions, and any portions
13 * thereof, and that both notices appear in supporting documentation.
14 *
15 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
16 * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
17 * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
18 *
19 * Carnegie Mellon requests users of this software to return to
20 *
21 *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
22 *  School of Computer Science
23 *  Carnegie Mellon University
24 *  Pittsburgh PA 15213-3890
25 *
26 * any improvements or extensions that they make and grant Carnegie the
27 * rights to redistribute these changes.
28 */
29
30#include <sys/cdefs.h>
31__KERNEL_RCSID(0, "$NetBSD: tsrtc.c,v 1.6 2008/04/04 09:33:07 tsutsui Exp $");
32
33#include <sys/cdefs.h>			/* RCS ID & Copyright macro defns */
34
35#include <sys/param.h>
36#include <sys/kernel.h>
37#include <sys/systm.h>
38#include <sys/device.h>
39
40#include <sys/bus.h>
41
42#include <dev/clock_subr.h>
43#include <dev/ic/mc146818reg.h>
44#include <dev/ic/mc146818var.h>
45
46#include <evbarm/tsarm/tspldvar.h>
47#include <evbarm/tsarm/tsarmreg.h>
48
49int	tsrtc_match(device_t, cfdata_t, void *);
50void	tsrtc_attach(device_t, device_t, void *);
51
52struct tsrtc_softc {
53	struct mc146818_softc	sc_mc;
54	bus_space_tag_t		sc_iot;
55	bus_space_handle_t	sc_dath;
56	bus_space_handle_t	sc_idxh;
57};
58
59CFATTACH_DECL_NEW(tsrtc, sizeof (struct tsrtc_softc),
60    tsrtc_match, tsrtc_attach, NULL, NULL);
61
62void	tsrtc_write(struct mc146818_softc *, u_int, u_int);
63u_int	tsrtc_read(struct mc146818_softc *, u_int);
64
65
66int
67tsrtc_match(device_t parent, cfdata_t cf, void *aux)
68{
69	struct tspld_attach_args *aa = aux;
70	struct tsrtc_softc tsrtc, *tsc;
71	struct mc146818_softc *sc;
72	unsigned int t1, t2;
73	static int found = -1;
74
75	if (found != -1)
76		return found;
77
78	tsc = &tsrtc;
79	sc = &tsc->sc_mc;
80	tsc->sc_iot = aa->ta_iot;
81	if (bus_space_map(tsc->sc_iot, TS7XXX_IO8_HWBASE + TS7XXX_RTCIDX, 1, 0,
82		 &tsc->sc_idxh))
83		return (0);
84	if (bus_space_map(tsc->sc_iot, TS7XXX_IO8_HWBASE + TS7XXX_RTCDAT, 1, 0,
85		 &tsc->sc_dath))
86		return (0);
87
88	/* Read from the seconds counter. */
89	t1 = FROMBCD(tsrtc_read(sc, MC_SEC));
90	if (t1 > 59)
91		goto unmap;
92
93	/* Wait, then look again. */
94	DELAY(1100000);
95	t2 = FROMBCD(tsrtc_read(sc, MC_SEC));
96	if (t2 > 59)
97		goto unmap;
98
99        /* If [1,2) seconds have passed since, call it a clock. */
100	if ((t1 + 1) % 60 == t2 || (t1 + 2) % 60 == t2)
101		found = 1;
102
103 unmap:
104	bus_space_unmap(tsc->sc_iot, tsc->sc_idxh, 1);
105	bus_space_unmap(tsc->sc_iot, tsc->sc_dath, 1);
106
107	return (found);
108}
109
110void
111tsrtc_attach(device_t parent, device_t self, void *aux)
112{
113	struct tsrtc_softc *tsc = device_private(self);
114	struct mc146818_softc *sc = &tsc->sc_mc;
115	struct tspld_attach_args *aa = aux;
116
117	sc->sc_dev = self;
118	tsc->sc_iot = aa->ta_iot;
119	if (bus_space_map(tsc->sc_iot, TS7XXX_IO8_HWBASE + TS7XXX_RTCIDX,
120	    1, 0, &tsc->sc_idxh))
121		panic("tsrtc_attach: couldn't map clock I/O space");
122	if (bus_space_map(tsc->sc_iot, TS7XXX_IO8_HWBASE + TS7XXX_RTCDAT,
123	    1, 0, &tsc->sc_dath))
124		panic("tsrtc_attach: couldn't map clock I/O space");
125
126	sc->sc_year0 = 2000;
127	sc->sc_mcread = tsrtc_read;
128	sc->sc_mcwrite = tsrtc_write;
129	sc->sc_flag = MC146818_BCD;
130	mc146818_attach(sc);
131
132	aprint_normal("\n");
133
134	(*sc->sc_mcwrite)(sc, MC_REGB, MC_REGB_24HR);
135}
136
137void
138tsrtc_write(struct mc146818_softc *mc_sc, u_int reg, u_int datum)
139{
140	struct tsrtc_softc *sc = (struct tsrtc_softc *)mc_sc;
141
142	bus_space_write_1(sc->sc_iot, sc->sc_idxh, 0, reg);
143	bus_space_write_1(sc->sc_iot, sc->sc_dath, 0, datum);
144}
145
146u_int
147tsrtc_read(struct mc146818_softc *mc_sc, u_int reg)
148{
149	struct tsrtc_softc *sc = (struct tsrtc_softc *)mc_sc;
150	u_int datum;
151
152	bus_space_write_1(sc->sc_iot, sc->sc_idxh, 0, reg);
153	datum = bus_space_read_1(sc->sc_iot, sc->sc_dath, 0);
154
155	return (datum);
156}
157