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/param.h> 30 #include <sys/bus.h> 31 #include <sys/conf.h> 32 #include <sys/rman.h> 33 #include <sys/kernel.h> 34 #include <sys/module.h> 35 #include <sys/resource.h> 36 #include <sys/systm.h> 37 38 #include <machine/bus.h> 39 #include <dev/ofw/ofw_bus_subr.h> 40 41 #define AL_NB_ACF_MISC_OFFSET 0xD0 42 #define AL_NB_ACF_MISC_READ_BYPASS (1 << 30) 43 44 static struct resource_spec nb_service_spec[] = { 45 { SYS_RES_MEMORY, 0, RF_ACTIVE }, 46 { -1, 0 } 47 }; 48 49 struct nb_service_softc { 50 struct resource *res; 51 }; 52 53 static int nb_service_probe(device_t dev); 54 static int nb_service_attach(device_t dev); 55 static int nb_service_detach(device_t dev); 56 57 static device_method_t nb_service_methods[] = { 58 DEVMETHOD(device_probe, nb_service_probe), 59 DEVMETHOD(device_attach, nb_service_attach), 60 DEVMETHOD(device_detach, nb_service_detach), 61 { 0, 0 } 62 }; 63 64 static driver_t nb_service_driver = { 65 "nb_service", 66 nb_service_methods, 67 sizeof(struct nb_service_softc) 68 }; 69 70 EARLY_DRIVER_MODULE(nb_service, simplebus, nb_service_driver, 0, 0, 71 BUS_PASS_CPU + BUS_PASS_ORDER_MIDDLE); 72 EARLY_DRIVER_MODULE(nb_service, ofwbus, nb_service_driver, 0, 0, 73 BUS_PASS_CPU + BUS_PASS_ORDER_MIDDLE); 74 75 static int 76 nb_service_probe(device_t dev) 77 { 78 79 if (!ofw_bus_status_okay(dev)) 80 return (ENXIO); 81 82 if (!ofw_bus_is_compatible(dev, "annapurna-labs,al-nb-service")) 83 return (ENXIO); 84 85 device_set_desc(dev, "Alpine North Bridge Service"); 86 87 return (BUS_PROBE_DEFAULT); 88 } 89 90 static int 91 nb_service_attach(device_t dev) 92 { 93 struct nb_service_softc *sc; 94 uint32_t val; 95 int err; 96 97 sc = device_get_softc(dev); 98 99 err = bus_alloc_resources(dev, nb_service_spec, &sc->res); 100 if (err != 0) { 101 device_printf(dev, "could not allocate resources\n"); 102 return (err); 103 } 104 105 /* Do not allow reads to bypass writes to different addresses */ 106 val = bus_read_4(sc->res, AL_NB_ACF_MISC_OFFSET); 107 val &= ~AL_NB_ACF_MISC_READ_BYPASS; 108 bus_write_4(sc->res, AL_NB_ACF_MISC_OFFSET, val); 109 110 return (0); 111 } 112 113 static int 114 nb_service_detach(device_t dev) 115 { 116 struct nb_service_softc *sc; 117 118 sc = device_get_softc(dev); 119 120 bus_release_resources(dev, nb_service_spec, &sc->res); 121 122 return (0); 123 } 124