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/param.h> 37 #include <sys/systm.h> 38 #include <sys/bus.h> 39 #include <sys/kernel.h> 40 #include <sys/lock.h> 41 #include <sys/module.h> 42 #include <sys/mutex.h> 43 #include <sys/rman.h> 44 45 #include <machine/bus.h> 46 47 #include <dev/ofw/ofw_bus.h> 48 #include <dev/ofw/ofw_bus_subr.h> 49 50 #include "syscon_if.h" 51 #include "syscon.h" 52 #include "syscon_generic.h" 53 54 MALLOC_DECLARE(M_SYSCON); 55 56 static uint32_t syscon_generic_unlocked_read_4(struct syscon *syscon, 57 bus_size_t offset); 58 static int syscon_generic_unlocked_write_4(struct syscon *syscon, 59 bus_size_t offset, uint32_t val); 60 static int syscon_generic_unlocked_modify_4(struct syscon *syscon, 61 bus_size_t offset, uint32_t clear_bits, uint32_t set_bits); 62 static int syscon_generic_detach(device_t dev); 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_unlocked_read_4, syscon_generic_unlocked_read_4), 81 SYSCONMETHOD(syscon_unlocked_write_4, syscon_generic_unlocked_write_4), 82 SYSCONMETHOD(syscon_unlocked_modify_4, syscon_generic_unlocked_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_unlocked_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 SYSCON_ASSERT_LOCKED(sc); 97 val = bus_read_4(sc->mem_res, offset); 98 return (val); 99 } 100 101 static int 102 syscon_generic_unlocked_write_4(struct syscon *syscon, bus_size_t offset, uint32_t val) 103 { 104 struct syscon_generic_softc *sc; 105 106 sc = device_get_softc(syscon->pdev); 107 SYSCON_ASSERT_LOCKED(sc); 108 bus_write_4(sc->mem_res, offset, val); 109 return (0); 110 } 111 112 static int 113 syscon_generic_unlocked_modify_4(struct syscon *syscon, bus_size_t offset, 114 uint32_t clear_bits, uint32_t set_bits) 115 { 116 struct syscon_generic_softc *sc; 117 uint32_t val; 118 119 sc = device_get_softc(syscon->pdev); 120 SYSCON_ASSERT_LOCKED(sc); 121 val = bus_read_4(sc->mem_res, offset); 122 val &= ~clear_bits; 123 val |= set_bits; 124 bus_write_4(sc->mem_res, offset, val); 125 return (0); 126 } 127 128 static void 129 syscon_generic_lock(device_t dev) 130 { 131 struct syscon_generic_softc *sc; 132 133 sc = device_get_softc(dev); 134 SYSCON_LOCK(sc); 135 } 136 137 static void 138 syscon_generic_unlock(device_t dev) 139 { 140 struct syscon_generic_softc *sc; 141 142 sc = device_get_softc(dev); 143 SYSCON_UNLOCK(sc); 144 } 145 146 static int 147 syscon_generic_probe(device_t dev) 148 { 149 150 if (!ofw_bus_status_okay(dev)) 151 return (ENXIO); 152 if (ofw_bus_search_compatible(dev, compat_data)->ocd_data == 0) 153 return (ENXIO); 154 155 device_set_desc(dev, "syscon"); 156 if (!bootverbose) 157 device_quiet(dev); 158 159 return (BUS_PROBE_GENERIC); 160 } 161 162 static int 163 syscon_generic_attach(device_t dev) 164 { 165 struct syscon_generic_softc *sc; 166 int rid, rv; 167 168 sc = device_get_softc(dev); 169 sc->dev = dev; 170 rid = 0; 171 172 sc->mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid, 173 RF_ACTIVE); 174 if (sc->mem_res == NULL) { 175 device_printf(dev, "Cannot allocate memory resource\n"); 176 return (ENXIO); 177 } 178 179 SYSCON_LOCK_INIT(sc); 180 sc->syscon = syscon_create_ofw_node(dev, &syscon_generic_class, 181 ofw_bus_get_node(dev)); 182 if (sc->syscon == NULL) { 183 device_printf(dev, "Failed to create/register syscon\n"); 184 syscon_generic_detach(dev); 185 return (ENXIO); 186 } 187 if (ofw_bus_is_compatible(dev, "simple-bus")) { 188 rv = simplebus_attach_impl(sc->dev); 189 if (rv != 0) { 190 device_printf(dev, "Failed to create simplebus\n"); 191 syscon_generic_detach(dev); 192 return (ENXIO); 193 } 194 sc->simplebus_attached = true; 195 } 196 197 return (bus_generic_attach(dev)); 198 } 199 200 static int 201 syscon_generic_detach(device_t dev) 202 { 203 struct syscon_generic_softc *sc; 204 205 sc = device_get_softc(dev); 206 if (sc->syscon != NULL) { 207 syscon_unregister(sc->syscon); 208 free(sc->syscon, M_SYSCON); 209 } 210 if (sc->simplebus_attached) 211 simplebus_detach(dev); 212 SYSCON_LOCK_DESTROY(sc); 213 214 if (sc->mem_res != NULL) 215 bus_release_resource(dev, SYS_RES_MEMORY, 0, sc->mem_res); 216 return (0); 217 } 218 219 static device_method_t syscon_generic_dmethods[] = { 220 /* Device interface */ 221 DEVMETHOD(device_probe, syscon_generic_probe), 222 DEVMETHOD(device_attach, syscon_generic_attach), 223 DEVMETHOD(device_detach, syscon_generic_detach), 224 225 DEVMETHOD(syscon_device_lock, syscon_generic_lock), 226 DEVMETHOD(syscon_device_unlock, syscon_generic_unlock), 227 228 DEVMETHOD_END 229 }; 230 231 DEFINE_CLASS_1(syscon_generic_dev, syscon_generic_driver, syscon_generic_dmethods, 232 sizeof(struct syscon_generic_softc), simplebus_driver); 233 234 EARLY_DRIVER_MODULE(syscon_generic, simplebus, syscon_generic_driver, 0, 0, 235 BUS_PASS_DEFAULT); 236 MODULE_VERSION(syscon_generic, 1); 237