Home | History | Annotate | Line # | Download | only in tsarm 
      1 /*	$NetBSD: tsrtc.c,v 1.8 2014/11/20 16:34:25 christos 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 (at) 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 1.8 2014/11/20 16:34:25 christos 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 
     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 = bcdtobin(tsrtc_read(sc, MC_SEC));
     90 	if (t1 > 59)
     91 		goto unmap;
     92 
     93 	/* Wait, then look again. */
     94 	DELAY(1100000);
     95 	t2 = bcdtobin(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 }
    157