sys/arch/evbarm/tsarm/tsrtc.c

   1 /*      $NetBSD: tsrtc.c,v 1.5 2008/03/29 05:42:45 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 1.5 2008/03/29 05:42:45 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 <machine/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
  49 int     tsrtc_match(device_t, cfdata_t, void *);
  50 void    tsrtc_attach(device_t, device_t, void *);
  51
  52 struct 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
  59 CFATTACH_DECL_NEW(tsrtc, sizeof (struct tsrtc_softc),
  60     tsrtc_match, tsrtc_attach, NULL, NULL);
  61
  62 void    tsrtc_write(struct mc146818_softc *, u_int, u_int);
  63 u_int   tsrtc_read(struct mc146818_softc *, u_int);
  64
  65
  66 int
  67 tsrtc_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
 110 void
 111 tsrtc_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
 137 void
 138 tsrtc_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
 146 u_int
 147 tsrtc_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 }