1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 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 #include <sys/param.h> 38 #include <sys/systm.h> 39 #include <sys/bus.h> 40 #include <sys/kernel.h> 41 #include <sys/lock.h> 42 #include <sys/module.h> 43 #include <sys/mutex.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_unlocked_read_4(struct syscon *syscon, 58 bus_size_t offset); 59 static int syscon_generic_unlocked_write_4(struct syscon *syscon, 60 bus_size_t offset, uint32_t val); 61 static int syscon_generic_unlocked_modify_4(struct syscon *syscon, 62 bus_size_t offset, uint32_t clear_bits, uint32_t set_bits); 63 static int syscon_generic_detach(device_t dev); 64 /* 65 * Generic syscon driver (FDT) 66 */ 67 static struct ofw_compat_data compat_data[] = { 68 {"syscon", 1}, 69 {NULL, 0} 70 }; 71 72 #define SYSCON_LOCK(_sc) mtx_lock_spin(&(_sc)->mtx) 73 #define SYSCON_UNLOCK(_sc) mtx_unlock_spin(&(_sc)->mtx) 74 #define SYSCON_LOCK_INIT(_sc) mtx_init(&(_sc)->mtx, \ 75 device_get_nameunit((_sc)->dev), "syscon", MTX_SPIN) 76 #define SYSCON_LOCK_DESTROY(_sc) mtx_destroy(&(_sc)->mtx); 77 #define SYSCON_ASSERT_LOCKED(_sc) mtx_assert(&(_sc)->mtx, MA_OWNED); 78 #define SYSCON_ASSERT_UNLOCKED(_sc) mtx_assert(&(_sc)->mtx, MA_NOTOWNED); 79 80 static syscon_method_t syscon_generic_methods[] = { 81 SYSCONMETHOD(syscon_unlocked_read_4, syscon_generic_unlocked_read_4), 82 SYSCONMETHOD(syscon_unlocked_write_4, syscon_generic_unlocked_write_4), 83 SYSCONMETHOD(syscon_unlocked_modify_4, syscon_generic_unlocked_modify_4), 84 85 SYSCONMETHOD_END 86 }; 87 DEFINE_CLASS_1(syscon_generic, syscon_generic_class, syscon_generic_methods, 88 0, syscon_class); 89 90 static uint32_t 91 syscon_generic_unlocked_read_4(struct syscon *syscon, bus_size_t offset) 92 { 93 struct syscon_generic_softc *sc; 94 uint32_t val; 95 96 sc = device_get_softc(syscon->pdev); 97 SYSCON_ASSERT_LOCKED(sc); 98 val = bus_read_4(sc->mem_res, offset); 99 return (val); 100 } 101 102 static int 103 syscon_generic_unlocked_write_4(struct syscon *syscon, bus_size_t offset, uint32_t val) 104 { 105 struct syscon_generic_softc *sc; 106 107 sc = device_get_softc(syscon->pdev); 108 SYSCON_ASSERT_LOCKED(sc); 109 bus_write_4(sc->mem_res, offset, val); 110 return (0); 111 } 112 113 static int 114 syscon_generic_unlocked_modify_4(struct syscon *syscon, bus_size_t offset, 115 uint32_t clear_bits, uint32_t set_bits) 116 { 117 struct syscon_generic_softc *sc; 118 uint32_t val; 119 120 sc = device_get_softc(syscon->pdev); 121 SYSCON_ASSERT_LOCKED(sc); 122 val = bus_read_4(sc->mem_res, offset); 123 val &= ~clear_bits; 124 val |= set_bits; 125 bus_write_4(sc->mem_res, offset, val); 126 return (0); 127 } 128 129 static void 130 syscon_generic_lock(device_t dev) 131 { 132 struct syscon_generic_softc *sc; 133 134 sc = device_get_softc(dev); 135 SYSCON_LOCK(sc); 136 } 137 138 static void 139 syscon_generic_unlock(device_t dev) 140 { 141 struct syscon_generic_softc *sc; 142 143 sc = device_get_softc(dev); 144 SYSCON_UNLOCK(sc); 145 } 146 147 static int 148 syscon_generic_probe(device_t dev) 149 { 150 151 if (!ofw_bus_status_okay(dev)) 152 return (ENXIO); 153 if (ofw_bus_search_compatible(dev, compat_data)->ocd_data == 0) 154 return (ENXIO); 155 156 device_set_desc(dev, "syscon"); 157 if (!bootverbose) 158 device_quiet(dev); 159 160 return (BUS_PROBE_GENERIC); 161 } 162 163 static int 164 syscon_generic_attach(device_t dev) 165 { 166 struct syscon_generic_softc *sc; 167 int rid, rv; 168 169 sc = device_get_softc(dev); 170 sc->dev = dev; 171 rid = 0; 172 173 sc->mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid, 174 RF_ACTIVE); 175 if (sc->mem_res == NULL) { 176 device_printf(dev, "Cannot allocate memory resource\n"); 177 return (ENXIO); 178 } 179 180 SYSCON_LOCK_INIT(sc); 181 sc->syscon = syscon_create_ofw_node(dev, &syscon_generic_class, 182 ofw_bus_get_node(dev)); 183 if (sc->syscon == NULL) { 184 device_printf(dev, "Failed to create/register syscon\n"); 185 syscon_generic_detach(dev); 186 return (ENXIO); 187 } 188 if (ofw_bus_is_compatible(dev, "simple-bus")) { 189 rv = simplebus_attach_impl(sc->dev); 190 if (rv != 0) { 191 device_printf(dev, "Failed to create simplebus\n"); 192 syscon_generic_detach(dev); 193 return (ENXIO); 194 } 195 sc->simplebus_attached = true; 196 } 197 198 return (bus_generic_attach(dev)); 199 } 200 201 static int 202 syscon_generic_detach(device_t dev) 203 { 204 struct syscon_generic_softc *sc; 205 206 sc = device_get_softc(dev); 207 if (sc->syscon != NULL) { 208 syscon_unregister(sc->syscon); 209 free(sc->syscon, M_SYSCON); 210 } 211 if (sc->simplebus_attached) 212 simplebus_detach(dev); 213 SYSCON_LOCK_DESTROY(sc); 214 215 if (sc->mem_res != NULL) 216 bus_release_resource(dev, SYS_RES_MEMORY, 0, sc->mem_res); 217 return (0); 218 } 219 220 static device_method_t syscon_generic_dmethods[] = { 221 /* Device interface */ 222 DEVMETHOD(device_probe, syscon_generic_probe), 223 DEVMETHOD(device_attach, syscon_generic_attach), 224 DEVMETHOD(device_detach, syscon_generic_detach), 225 226 DEVMETHOD(syscon_device_lock, syscon_generic_lock), 227 DEVMETHOD(syscon_device_unlock, syscon_generic_unlock), 228 229 DEVMETHOD_END 230 }; 231 232 DEFINE_CLASS_1(syscon_generic_dev, syscon_generic_driver, syscon_generic_dmethods, 233 sizeof(struct syscon_generic_softc), simplebus_driver); 234 235 EARLY_DRIVER_MODULE(syscon_generic, simplebus, syscon_generic_driver, 0, 0, 236 BUS_PASS_DEFAULT); 237 MODULE_VERSION(syscon_generic, 1); 238