1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2015 Michal Meloun 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 * 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 /* 30 * This is a generic syscon driver, whose purpose is to provide access to 31 * various unrelated bits packed in a single register space. It is usually used 32 * as a fallback to more specific driver, but works well enough for simple 33 * access. 34 */ 35 36 #include <sys/cdefs.h> 37 __FBSDID("$FreeBSD$"); 38 #include <sys/param.h> 39 #include <sys/systm.h> 40 #include <sys/bus.h> 41 #include <sys/kernel.h> 42 #include <sys/lock.h> 43 #include <sys/module.h> 44 #include <sys/rman.h> 45 46 #include <machine/bus.h> 47 48 #include <dev/ofw/ofw_bus.h> 49 #include <dev/ofw/ofw_bus_subr.h> 50 51 #include "syscon_if.h" 52 #include "syscon.h" 53 #include "syscon_generic.h" 54 55 MALLOC_DECLARE(M_SYSCON); 56 57 static uint32_t syscon_generic_read_4(struct syscon *syscon, bus_size_t offset); 58 static int syscon_generic_write_4(struct syscon *syscon, bus_size_t offset, 59 uint32_t val); 60 static int syscon_generic_modify_4(struct syscon *syscon, bus_size_t offset, 61 uint32_t clear_bits, uint32_t set_bits); 62 63 /* 64 * Generic syscon driver (FDT) 65 */ 66 static struct ofw_compat_data compat_data[] = { 67 {"syscon", 1}, 68 {NULL, 0} 69 }; 70 71 #define SYSCON_LOCK(_sc) mtx_lock_spin(&(_sc)->mtx) 72 #define SYSCON_UNLOCK(_sc) mtx_unlock_spin(&(_sc)->mtx) 73 #define SYSCON_LOCK_INIT(_sc) mtx_init(&(_sc)->mtx, \ 74 device_get_nameunit((_sc)->dev), "syscon", MTX_SPIN) 75 #define SYSCON_LOCK_DESTROY(_sc) mtx_destroy(&(_sc)->mtx); 76 #define SYSCON_ASSERT_LOCKED(_sc) mtx_assert(&(_sc)->mtx, MA_OWNED); 77 #define SYSCON_ASSERT_UNLOCKED(_sc) mtx_assert(&(_sc)->mtx, MA_NOTOWNED); 78 79 static syscon_method_t syscon_generic_methods[] = { 80 SYSCONMETHOD(syscon_read_4, syscon_generic_read_4), 81 SYSCONMETHOD(syscon_write_4, syscon_generic_write_4), 82 SYSCONMETHOD(syscon_modify_4, syscon_generic_modify_4), 83 84 SYSCONMETHOD_END 85 }; 86 DEFINE_CLASS_1(syscon_generic, syscon_generic_class, syscon_generic_methods, 87 0, syscon_class); 88 89 static uint32_t 90 syscon_generic_read_4(struct syscon *syscon, bus_size_t offset) 91 { 92 struct syscon_generic_softc *sc; 93 uint32_t val; 94 95 sc = device_get_softc(syscon->pdev); 96 97 SYSCON_LOCK(sc); 98 val = bus_read_4(sc->mem_res, offset); 99 SYSCON_UNLOCK(sc); 100 return (val); 101 } 102 103 static int 104 syscon_generic_write_4(struct syscon *syscon, bus_size_t offset, uint32_t val) 105 { 106 struct syscon_generic_softc *sc; 107 108 sc = device_get_softc(syscon->pdev); 109 110 SYSCON_LOCK(sc); 111 bus_write_4(sc->mem_res, offset, val); 112 SYSCON_UNLOCK(sc); 113 return (0); 114 } 115 116 static int 117 syscon_generic_modify_4(struct syscon *syscon, bus_size_t offset, 118 uint32_t clear_bits, uint32_t set_bits) 119 { 120 struct syscon_generic_softc *sc; 121 uint32_t val; 122 123 sc = device_get_softc(syscon->pdev); 124 125 SYSCON_LOCK(sc); 126 val = bus_read_4(sc->mem_res, offset); 127 val &= ~clear_bits; 128 val |= set_bits; 129 bus_write_4(sc->mem_res, offset, val); 130 SYSCON_UNLOCK(sc); 131 return (0); 132 } 133 134 static int 135 syscon_generic_probe(device_t dev) 136 { 137 138 if (!ofw_bus_status_okay(dev)) 139 return (ENXIO); 140 if (ofw_bus_search_compatible(dev, compat_data)->ocd_data == 0) 141 return (ENXIO); 142 143 device_set_desc(dev, "syscon"); 144 return (BUS_PROBE_GENERIC); 145 } 146 147 static int 148 syscon_generic_attach(device_t dev) 149 { 150 struct syscon_generic_softc *sc; 151 int rid; 152 153 sc = device_get_softc(dev); 154 sc->dev = dev; 155 rid = 0; 156 157 sc->mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid, 158 RF_ACTIVE); 159 if (sc->mem_res == NULL) { 160 device_printf(dev, "Cannot allocate memory resource\n"); 161 return (ENXIO); 162 } 163 164 SYSCON_LOCK_INIT(sc); 165 sc->syscon = syscon_create_ofw_node(dev, &syscon_generic_class, 166 ofw_bus_get_node(dev)); 167 if (sc->syscon == NULL) { 168 device_printf(dev, "Failed to create/register syscon\n"); 169 return (ENXIO); 170 } 171 return (0); 172 } 173 174 static int 175 syscon_generic_detach(device_t dev) 176 { 177 struct syscon_generic_softc *sc; 178 179 sc = device_get_softc(dev); 180 if (sc->syscon != NULL) { 181 syscon_unregister(sc->syscon); 182 free(sc->syscon, M_SYSCON); 183 } 184 185 SYSCON_LOCK_DESTROY(sc); 186 187 if (sc->mem_res != NULL) 188 bus_release_resource(dev, SYS_RES_MEMORY, 0, sc->mem_res); 189 return (0); 190 } 191 192 static device_method_t syscon_generic_dmethods[] = { 193 /* Device interface */ 194 DEVMETHOD(device_probe, syscon_generic_probe), 195 DEVMETHOD(device_attach, syscon_generic_attach), 196 DEVMETHOD(device_detach, syscon_generic_detach), 197 198 DEVMETHOD_END 199 }; 200 201 DEFINE_CLASS_0(syscon_generic, syscon_generic_driver, syscon_generic_dmethods, 202 sizeof(struct syscon_generic_softc)); 203 static devclass_t syscon_generic_devclass; 204 205 EARLY_DRIVER_MODULE(syscon_generic, simplebus, syscon_generic_driver, 206 syscon_generic_devclass, 0, 0, BUS_PASS_DEFAULT); 207 MODULE_VERSION(syscon_generic, 1); 208