| 1 | /* $NetBSD: hpet.c,v 1.13 2011/10/31 12:47:15 yamt Exp $ */ |
| 2 | |
| 3 | /* |
| 4 | * Copyright (c) 2006 Nicolas Joly |
| 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 author may not be used to endorse or promote products |
| 16 | * derived from this software without specific prior written permission. |
| 17 | * |
| 18 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS |
| 19 | * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED |
| 20 | * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
| 21 | * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS |
| 22 | * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
| 23 | * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
| 24 | * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
| 25 | * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
| 26 | * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| 27 | * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
| 28 | * POSSIBILITY OF SUCH DAMAGE. |
| 29 | */ |
| 30 | |
| 31 | /* |
| 32 | * High Precision Event Timer. |
| 33 | */ |
| 34 | |
| 35 | #include <sys/cdefs.h> |
| 36 | __KERNEL_RCSID(0, "$NetBSD: hpet.c,v 1.13 2011/10/31 12:47:15 yamt Exp $" ); |
| 37 | |
| 38 | #include <sys/systm.h> |
| 39 | #include <sys/device.h> |
| 40 | #include <sys/module.h> |
| 41 | |
| 42 | #include <sys/time.h> |
| 43 | #include <sys/timetc.h> |
| 44 | |
| 45 | #include <sys/bus.h> |
| 46 | |
| 47 | #include <dev/ic/hpetreg.h> |
| 48 | #include <dev/ic/hpetvar.h> |
| 49 | |
| 50 | static u_int hpet_get_timecount(struct timecounter *); |
| 51 | static bool hpet_resume(device_t, const pmf_qual_t *); |
| 52 | |
| 53 | int |
| 54 | hpet_detach(device_t dv, int flags) |
| 55 | { |
| 56 | struct hpet_softc *sc = device_private(dv); |
| 57 | int rc; |
| 58 | |
| 59 | if ((rc = tc_detach(&sc->sc_tc)) != 0) |
| 60 | return rc; |
| 61 | |
| 62 | pmf_device_deregister(dv); |
| 63 | |
| 64 | bus_space_write_4(sc->sc_memt, sc->sc_memh, HPET_CONFIG, sc->sc_config); |
| 65 | |
| 66 | return 0; |
| 67 | } |
| 68 | |
| 69 | void |
| 70 | hpet_attach_subr(device_t dv) |
| 71 | { |
| 72 | struct hpet_softc *sc = device_private(dv); |
| 73 | struct timecounter *tc; |
| 74 | uint64_t tmp; |
| 75 | uint32_t val; |
| 76 | int i; |
| 77 | |
| 78 | tc = &sc->sc_tc; |
| 79 | |
| 80 | tc->tc_name = device_xname(dv); |
| 81 | tc->tc_get_timecount = hpet_get_timecount; |
| 82 | tc->tc_quality = 2000; |
| 83 | |
| 84 | tc->tc_counter_mask = 0xffffffff; |
| 85 | |
| 86 | /* Get frequency */ |
| 87 | val = bus_space_read_4(sc->sc_memt, sc->sc_memh, HPET_PERIOD); |
| 88 | if (val == 0 || val > HPET_PERIOD_MAX) { |
| 89 | aprint_error_dev(dv, "invalid timer period\n" ); |
| 90 | return; |
| 91 | } |
| 92 | |
| 93 | /* |
| 94 | * The following loop is a workaround for AMD SB700 based systems. |
| 95 | * http://kerneltrap.org/mailarchive/git-commits-head/2008/8/17/2964724 |
| 96 | * http://git.kernel.org/git/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=a6825f1c1fa83b1e92b6715ee5771a4d6524d3b9 |
| 97 | */ |
| 98 | for (i = 0; bus_space_read_4(sc->sc_memt, sc->sc_memh, HPET_CONFIG) |
| 99 | == 0xffffffff; i++) { |
| 100 | if (i >= 1000) { |
| 101 | aprint_error_dev(dv, |
| 102 | "HPET_CONFIG value = 0xffffffff\n" ); |
| 103 | return; |
| 104 | } |
| 105 | } |
| 106 | |
| 107 | tmp = (1000000000000000ULL * 2) / val; |
| 108 | tc->tc_frequency = (tmp / 2) + (tmp & 1); |
| 109 | |
| 110 | /* Enable timer */ |
| 111 | val = bus_space_read_4(sc->sc_memt, sc->sc_memh, HPET_CONFIG); |
| 112 | sc->sc_config = val; |
| 113 | if ((val & HPET_CONFIG_ENABLE) == 0) { |
| 114 | val |= HPET_CONFIG_ENABLE; |
| 115 | bus_space_write_4(sc->sc_memt, sc->sc_memh, HPET_CONFIG, val); |
| 116 | } |
| 117 | |
| 118 | tc->tc_priv = sc; |
| 119 | tc_init(tc); |
| 120 | |
| 121 | if (!pmf_device_register(dv, NULL, hpet_resume)) |
| 122 | aprint_error_dev(dv, "couldn't establish power handler\n" ); |
| 123 | } |
| 124 | |
| 125 | static u_int |
| 126 | hpet_get_timecount(struct timecounter *tc) |
| 127 | { |
| 128 | struct hpet_softc *sc = tc->tc_priv; |
| 129 | |
| 130 | return bus_space_read_4(sc->sc_memt, sc->sc_memh, HPET_MCOUNT_LO); |
| 131 | } |
| 132 | |
| 133 | static bool |
| 134 | hpet_resume(device_t dv, const pmf_qual_t *qual) |
| 135 | { |
| 136 | struct hpet_softc *sc = device_private(dv); |
| 137 | uint32_t val; |
| 138 | |
| 139 | val = bus_space_read_4(sc->sc_memt, sc->sc_memh, HPET_CONFIG); |
| 140 | val |= HPET_CONFIG_ENABLE; |
| 141 | bus_space_write_4(sc->sc_memt, sc->sc_memh, HPET_CONFIG, val); |
| 142 | |
| 143 | return true; |
| 144 | } |
| 145 | |
| 146 | MODULE(MODULE_CLASS_DRIVER, hpet, NULL); |
| 147 | |
| 148 | #ifdef _MODULE |
| 149 | #include "ioconf.c" |
| 150 | #endif |
| 151 | |
| 152 | static int |
| 153 | hpet_modcmd(modcmd_t cmd, void *aux) |
| 154 | { |
| 155 | int rv = 0; |
| 156 | |
| 157 | switch (cmd) { |
| 158 | |
| 159 | case MODULE_CMD_INIT: |
| 160 | |
| 161 | #ifdef _MODULE |
| 162 | rv = config_init_component(cfdriver_ioconf_hpet, |
| 163 | cfattach_ioconf_hpet, cfdata_ioconf_hpet); |
| 164 | #endif |
| 165 | break; |
| 166 | |
| 167 | case MODULE_CMD_FINI: |
| 168 | |
| 169 | #ifdef _MODULE |
| 170 | rv = config_fini_component(cfdriver_ioconf_hpet, |
| 171 | cfattach_ioconf_hpet, cfdata_ioconf_hpet); |
| 172 | #endif |
| 173 | break; |
| 174 | |
| 175 | default: |
| 176 | rv = ENOTTY; |
| 177 | } |
| 178 | |
| 179 | return rv; |
| 180 | } |
| 181 | |