/* $NetBSD: hpet.c,v 1.10 2010/02/24 22:37:58 dyoung Exp $ */ /* * Copyright (c) 2006 Nicolas Joly * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. The name of the author may not be used to endorse or promote products * derived from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. */ /* * High Precision Event Timer. */ #include __KERNEL_RCSID(0, "$NetBSD: hpet.c,v 1.10 2010/02/24 22:37:58 dyoung Exp $"); #include #include #include #include #include #include #include #include static u_int hpet_get_timecount(struct timecounter *); static bool hpet_resume(device_t, const pmf_qual_t *); int hpet_detach(device_t dv, int flags) { struct hpet_softc *sc = device_private(dv); int rc; if ((rc = tc_detach(&sc->sc_tc)) != 0) return rc; pmf_device_deregister(dv); bus_space_write_4(sc->sc_memt, sc->sc_memh, HPET_CONFIG, sc->sc_config); return 0; } void hpet_attach_subr(device_t dv) { struct hpet_softc *sc = device_private(dv); struct timecounter *tc; uint32_t val; tc = &sc->sc_tc; tc->tc_name = device_xname(dv); tc->tc_get_timecount = hpet_get_timecount; tc->tc_quality = 2000; tc->tc_counter_mask = 0xffffffff; /* Get frequency */ val = bus_space_read_4(sc->sc_memt, sc->sc_memh, HPET_PERIOD); if (val == 0) { aprint_error_dev(dv, "invalid timer period\n"); return; } tc->tc_frequency = 1000000000000000ULL / val; /* Enable timer */ val = bus_space_read_4(sc->sc_memt, sc->sc_memh, HPET_CONFIG); sc->sc_config = val; if ((val & HPET_CONFIG_ENABLE) == 0) { val |= HPET_CONFIG_ENABLE; bus_space_write_4(sc->sc_memt, sc->sc_memh, HPET_CONFIG, val); } tc->tc_priv = sc; tc_init(tc); if (!pmf_device_register(dv, NULL, hpet_resume)) aprint_error_dev(dv, "couldn't establish power handler\n"); } static u_int hpet_get_timecount(struct timecounter *tc) { struct hpet_softc *sc = tc->tc_priv; return bus_space_read_4(sc->sc_memt, sc->sc_memh, HPET_MCOUNT_LO); } static bool hpet_resume(device_t dv, const pmf_qual_t *qual) { struct hpet_softc *sc = device_private(dv); uint32_t val; val = bus_space_read_4(sc->sc_memt, sc->sc_memh, HPET_CONFIG); val |= HPET_CONFIG_ENABLE; bus_space_write_4(sc->sc_memt, sc->sc_memh, HPET_CONFIG, val); return true; }