sys/arch/mvmeppc/isa/mkclock_isa.c

   1 /*      $NetBSD: mkclock_isa.c,v 1.12 2008/03/29 05:47:53 tsutsui Exp $ */
   2
   3 /*-
   4  * Copyright (c) 2002 The NetBSD Foundation, Inc.
   5  * All rights reserved.
   6  *
   7  * This code is derived from software contributed to The NetBSD Foundation
   8  * by Klaus J. Klein.
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
  20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
  23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  29  * POSSIBILITY OF SUCH DAMAGE.
  30  */
  31
  32 /*
  33  * Mostek MK48T18 time-of-day chip attachment to ISA bus, using two
  34  * 8-bit ports for address selection and one 8-bit port for data.
  35  */
  36
  37 #include <sys/cdefs.h>                  /* RCS ID & Copyright macro defns */
  38 __KERNEL_RCSID(0, "$NetBSD: mkclock_isa.c,v 1.12 2008/03/29 05:47:53 tsutsui Exp $");
  39
  40 #include <sys/param.h>
  41 #include <sys/kernel.h>
  42 #include <sys/systm.h>
  43 #include <sys/device.h>
  44
  45 #include <machine/bus.h>
  46
  47 #include <dev/clock_subr.h>
  48 #include <dev/ic/mk48txxreg.h>
  49 #include <dev/ic/mk48txxvar.h>
  50
  51 #include <dev/isa/isavar.h>
  52
  53
  54 /* Offsets of registers into ISA I/O space */
  55 #define MKCLOCK_STB0    0               /* Address low          */
  56 #define MKCLOCK_STB1    1               /* Address high         */
  57 #define MKCLOCK_DATA    3               /* Data port            */
  58
  59 #define MKCLOCK_NPORTS  (MKCLOCK_DATA - MKCLOCK_STB0 + 1)
  60
  61
  62 /* Autoconfiguration interface */
  63 int     mkclock_isa_match(device_t, cfdata_t, void *);
  64 void    mkclock_isa_attach(device_t, device_t, void *);
  65
  66 CFATTACH_DECL_NEW(mkclock_isa, sizeof(struct mk48txx_softc),
  67     mkclock_isa_match, mkclock_isa_attach, NULL, NULL);
  68
  69
  70 /* mk48txx interface */
  71 uint8_t mkclock_isa_nvrd(struct mk48txx_softc *, int);
  72 void    mkclock_isa_nvwr(struct mk48txx_softc *, int, uint8_t);
  73
  74
  75 int
  76 mkclock_isa_match(device_t parent, cfdata_t cf, void *aux)
  77 {
  78         struct isa_attach_args *ia = aux;
  79         struct mk48txx_softc mk48txx, *sc;
  80         uint8_t csr, ocsr;
  81         unsigned int t1, t2;
  82         int found;
  83
  84         found = 0;
  85
  86         if (ia->ia_nio < 1 ||
  87             (ia->ia_io[0].ir_addr != ISA_UNKNOWN_PORT &&
  88              ia->ia_io[0].ir_addr != 0x74))
  89                 return (0);
  90
  91         if (ia->ia_niomem > 0 &&
  92             (ia->ia_iomem[0].ir_addr != ISA_UNKNOWN_IOMEM))
  93                 return (0);
  94
  95         if (ia->ia_nirq > 0 &&
  96             (ia->ia_irq[0].ir_irq != ISA_UNKNOWN_IRQ))
  97                 return (0);
  98
  99         if (ia->ia_ndrq > 0 &&
 100             (ia->ia_drq[0].ir_drq != ISA_UNKNOWN_DRQ))
 101                 return (0);
 102
 103         /*
 104          * Map I/O space, then try to determine if it's really there.
 105          */
 106         sc = &mk48txx;
 107         sc->sc_bst = ia->ia_iot;
 108         if (bus_space_map(sc->sc_bst, 0x74, MKCLOCK_NPORTS, 0, &sc->sc_bsh))
 109                 return (0);
 110
 111         /* Supposedly no control bits are set after POST; check for this. */
 112         ocsr = mkclock_isa_nvrd(sc, MK48T18_CLKOFF + MK48TXX_ICSR);
 113         if (ocsr != 0)
 114                 goto unmap;
 115
 116         /* Set clock data to read mode, prohibiting updates from clock. */
 117         csr = ocsr | MK48TXX_CSR_READ;
 118         mkclock_isa_nvwr(sc, MK48T18_CLKOFF + MK48TXX_ICSR, csr);
 119         /* Compare. */
 120         if (mkclock_isa_nvrd(sc, MK48T18_CLKOFF + MK48TXX_ICSR) != csr)
 121                 goto restore;
 122
 123         /* Read from the seconds counter. */
 124         t1 = FROMBCD(mkclock_isa_nvrd(sc, MK48T18_CLKOFF + MK48TXX_ISEC));
 125         if (t1 > 59)
 126                 goto restore;
 127
 128         /* Make it tick again, wait, then look again. */
 129         mkclock_isa_nvwr(sc, MK48T18_CLKOFF + MK48TXX_ICSR, ocsr);
 130         DELAY(1100000);
 131         mkclock_isa_nvwr(sc, MK48T18_CLKOFF + MK48TXX_ICSR, csr);
 132         t2 = FROMBCD(mkclock_isa_nvrd(sc, MK48T18_CLKOFF + MK48TXX_ISEC));
 133         if (t2 > 59)
 134                 goto restore;
 135
 136         /* If [1,2) seconds have passed since, call it a clock. */
 137         if ((t1 + 1) % 60 == t2 || (t1 + 2) % 60 == t2)
 138                 found = 1;
 139
 140  restore:
 141         mkclock_isa_nvwr(sc, MK48T18_CLKOFF + MK48TXX_ICSR, ocsr);
 142  unmap:
 143         bus_space_unmap(sc->sc_bst, sc->sc_bsh, MKCLOCK_NPORTS);
 144
 145         if (found) {
 146                 ia->ia_nio = 1;
 147                 ia->ia_io[0].ir_addr = 0x74;
 148                 ia->ia_io[0].ir_size = MKCLOCK_NPORTS;
 149
 150                 ia->ia_niomem = 0;
 151                 ia->ia_nirq = 0;
 152                 ia->ia_ndrq = 0;
 153         }
 154
 155         return (found);
 156 }
 157
 158 void
 159 mkclock_isa_attach(device_t parent, device_t self, void *aux)
 160 {
 161         struct mk48txx_softc *sc = device_private(self);
 162         struct isa_attach_args *ia = aux;
 163
 164         sc->sc_dev = self;
 165
 166         /* Map I/O space. */
 167         sc->sc_bst = ia->ia_iot;
 168         if (bus_space_map(sc->sc_bst, ia->ia_io[0].ir_addr,
 169             ia->ia_io[0].ir_size, 0, &sc->sc_bsh))
 170                 panic("mkclock_isa_attach: couldn't map clock I/O space");
 171
 172         /* Attach to MI mk48txx driver. */
 173         sc->sc_model = "mk48t18";
 174         sc->sc_year0 = 1968;
 175         sc->sc_nvrd = mkclock_isa_nvrd;
 176         sc->sc_nvwr = mkclock_isa_nvwr;
 177
 178         mk48txx_attach(sc);
 179
 180         aprint_normal(" Timekeeper NVRAM/RTC\n");
 181 }
 182
 183 /*
 184  * Bus access methods for MI mk48txx driver.
 185  */
 186 uint8_t
 187 mkclock_isa_nvrd(struct mk48txx_softc *sc, int off)
 188 {
 189         bus_space_tag_t iot;
 190         bus_space_handle_t ioh;
 191         uint8_t datum;
 192         int s;
 193
 194         iot = sc->sc_bst;
 195         ioh = sc->sc_bsh;
 196
 197         s = splclock();
 198         bus_space_write_1(iot, ioh, MKCLOCK_STB0, off & 0xff);
 199         bus_space_write_1(iot, ioh, MKCLOCK_STB1, off >> 8);
 200         datum = bus_space_read_1(iot, ioh, MKCLOCK_DATA);
 201         splx(s);
 202
 203         return (datum);
 204 }
 205
 206 void
 207 mkclock_isa_nvwr(struct mk48txx_softc *sc, int off, uint8_t datum)
 208 {
 209         bus_space_tag_t iot;
 210         bus_space_handle_t ioh;
 211         int s;
 212
 213         iot = sc->sc_bst;
 214         ioh = sc->sc_bsh;
 215
 216         s = splclock();
 217         bus_space_write_1(iot, ioh, MKCLOCK_STB0, off & 0xff);
 218         bus_space_write_1(iot, ioh, MKCLOCK_STB1, off >> 8);
 219         bus_space_write_1(iot, ioh, MKCLOCK_DATA, datum);
 220         splx(s);
 221 }