1 /*- 2 * Copyright (c) 2015,2016 Annapurna Labs Ltd. and affiliates 3 * All rights reserved. 4 * 5 * Developed by Semihalf. 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 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 #include <sys/cdefs.h> 30 #include <sys/param.h> 31 #include <sys/bus.h> 32 #include <sys/conf.h> 33 #include <sys/rman.h> 34 #include <sys/kernel.h> 35 #include <sys/module.h> 36 #include <sys/resource.h> 37 #include <sys/systm.h> 38 39 #include <machine/bus.h> 40 #include <dev/ofw/ofw_bus_subr.h> 41 42 #define AL_NB_ACF_MISC_OFFSET 0xD0 43 #define AL_NB_ACF_MISC_READ_BYPASS (1 << 30) 44 45 static struct resource_spec nb_service_spec[] = { 46 { SYS_RES_MEMORY, 0, RF_ACTIVE }, 47 { -1, 0 } 48 }; 49 50 struct nb_service_softc { 51 struct resource *res; 52 }; 53 54 static int nb_service_probe(device_t dev); 55 static int nb_service_attach(device_t dev); 56 static int nb_service_detach(device_t dev); 57 58 static device_method_t nb_service_methods[] = { 59 DEVMETHOD(device_probe, nb_service_probe), 60 DEVMETHOD(device_attach, nb_service_attach), 61 DEVMETHOD(device_detach, nb_service_detach), 62 { 0, 0 } 63 }; 64 65 static driver_t nb_service_driver = { 66 "nb_service", 67 nb_service_methods, 68 sizeof(struct nb_service_softc) 69 }; 70 71 EARLY_DRIVER_MODULE(nb_service, simplebus, nb_service_driver, 0, 0, 72 BUS_PASS_CPU + BUS_PASS_ORDER_MIDDLE); 73 EARLY_DRIVER_MODULE(nb_service, ofwbus, nb_service_driver, 0, 0, 74 BUS_PASS_CPU + BUS_PASS_ORDER_MIDDLE); 75 76 static int 77 nb_service_probe(device_t dev) 78 { 79 80 if (!ofw_bus_status_okay(dev)) 81 return (ENXIO); 82 83 if (!ofw_bus_is_compatible(dev, "annapurna-labs,al-nb-service")) 84 return (ENXIO); 85 86 device_set_desc(dev, "Alpine North Bridge Service"); 87 88 return (BUS_PROBE_DEFAULT); 89 } 90 91 static int 92 nb_service_attach(device_t dev) 93 { 94 struct nb_service_softc *sc; 95 uint32_t val; 96 int err; 97 98 sc = device_get_softc(dev); 99 100 err = bus_alloc_resources(dev, nb_service_spec, &sc->res); 101 if (err != 0) { 102 device_printf(dev, "could not allocate resources\n"); 103 return (err); 104 } 105 106 /* Do not allow reads to bypass writes to different addresses */ 107 val = bus_read_4(sc->res, AL_NB_ACF_MISC_OFFSET); 108 val &= ~AL_NB_ACF_MISC_READ_BYPASS; 109 bus_write_4(sc->res, AL_NB_ACF_MISC_OFFSET, val); 110 111 return (0); 112 } 113 114 static int 115 nb_service_detach(device_t dev) 116 { 117 struct nb_service_softc *sc; 118 119 sc = device_get_softc(dev); 120 121 bus_release_resources(dev, nb_service_spec, &sc->res); 122 123 return (0); 124 } 125