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 __FBSDID("$FreeBSD$"); 31 32 #include <sys/param.h> 33 #include <sys/bus.h> 34 #include <sys/conf.h> 35 #include <sys/rman.h> 36 #include <sys/kernel.h> 37 #include <sys/module.h> 38 #include <sys/resource.h> 39 #include <sys/systm.h> 40 41 #include <machine/bus.h> 42 #include <dev/ofw/ofw_bus_subr.h> 43 44 #define AL_NB_ACF_MISC_OFFSET 0xD0 45 #define AL_NB_ACF_MISC_READ_BYPASS (1 << 30) 46 47 static struct resource_spec nb_service_spec[] = { 48 { SYS_RES_MEMORY, 0, RF_ACTIVE }, 49 { -1, 0 } 50 }; 51 52 struct nb_service_softc { 53 struct resource *res; 54 }; 55 56 static int nb_service_probe(device_t dev); 57 static int nb_service_attach(device_t dev); 58 static int nb_service_detach(device_t dev); 59 60 static device_method_t nb_service_methods[] = { 61 DEVMETHOD(device_probe, nb_service_probe), 62 DEVMETHOD(device_attach, nb_service_attach), 63 DEVMETHOD(device_detach, nb_service_detach), 64 65 { 0, 0 } 66 }; 67 68 static driver_t nb_service_driver = { 69 "nb_service", 70 nb_service_methods, 71 sizeof(struct nb_service_softc) 72 }; 73 74 static devclass_t nb_service_devclass; 75 76 EARLY_DRIVER_MODULE(nb_service, simplebus, nb_service_driver, 77 nb_service_devclass, 0, 0, BUS_PASS_CPU + BUS_PASS_ORDER_MIDDLE); 78 EARLY_DRIVER_MODULE(nb_service, ofwbus, nb_service_driver, 79 nb_service_devclass, 0, 0, BUS_PASS_CPU + BUS_PASS_ORDER_MIDDLE); 80 81 static int 82 nb_service_probe(device_t dev) 83 { 84 85 if (!ofw_bus_status_okay(dev)) 86 return (ENXIO); 87 88 if (!ofw_bus_is_compatible(dev, "annapurna-labs,al-nb-service")) 89 return (ENXIO); 90 91 device_set_desc(dev, "Alpine North Bridge Service"); 92 93 return (BUS_PROBE_DEFAULT); 94 } 95 96 static int 97 nb_service_attach(device_t dev) 98 { 99 struct nb_service_softc *sc; 100 uint32_t val; 101 int err; 102 103 sc = device_get_softc(dev); 104 105 err = bus_alloc_resources(dev, nb_service_spec, &sc->res); 106 if (err != 0) { 107 device_printf(dev, "could not allocate resources\n"); 108 return (err); 109 } 110 111 /* Do not allow reads to bypass writes to different addresses */ 112 val = bus_read_4(sc->res, AL_NB_ACF_MISC_OFFSET); 113 val &= ~AL_NB_ACF_MISC_READ_BYPASS; 114 bus_write_4(sc->res, AL_NB_ACF_MISC_OFFSET, val); 115 116 return (0); 117 } 118 119 static int 120 nb_service_detach(device_t dev) 121 { 122 struct nb_service_softc *sc; 123 124 sc = device_get_softc(dev); 125 126 bus_release_resources(dev, nb_service_spec, &sc->res); 127 128 return (0); 129 } 130