1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2017 Kyle Evans <[email protected]> 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 "opt_platform.h" 39 40 #include <sys/param.h> 41 #include <sys/systm.h> 42 #include <sys/bus.h> 43 #include <sys/kernel.h> 44 #include <sys/kobj.h> 45 #include <sys/lock.h> 46 #include <sys/module.h> 47 #include <sys/rman.h> 48 #include <sys/sx.h> 49 #include <sys/queue.h> 50 51 #include <machine/bus.h> 52 53 #ifdef FDT 54 #include <dev/ofw/ofw_bus.h> 55 #include <dev/ofw/ofw_bus_subr.h> 56 #endif 57 58 #include "syscon_if.h" 59 #include "syscon.h" 60 61 /* 62 * Syscon interface details 63 */ 64 typedef TAILQ_HEAD(syscon_list, syscon) syscon_list_t; 65 66 /* 67 * Declarations 68 */ 69 static int syscon_method_init(struct syscon *syscon); 70 static int syscon_method_uninit(struct syscon *syscon); 71 72 MALLOC_DEFINE(M_SYSCON, "syscon", "Syscon driver"); 73 74 static syscon_list_t syscon_list = TAILQ_HEAD_INITIALIZER(syscon_list); 75 static struct sx syscon_topo_lock; 76 SX_SYSINIT(syscon_topology, &syscon_topo_lock, "Syscon topology lock"); 77 78 /* 79 * Syscon methods. 80 */ 81 static syscon_method_t syscon_methods[] = { 82 SYSCONMETHOD(syscon_init, syscon_method_init), 83 SYSCONMETHOD(syscon_uninit, syscon_method_uninit), 84 85 SYSCONMETHOD_END 86 }; 87 DEFINE_CLASS_0(syscon, syscon_class, syscon_methods, 0); 88 89 #define SYSCON_TOPO_SLOCK() sx_slock(&syscon_topo_lock) 90 #define SYSCON_TOPO_XLOCK() sx_xlock(&syscon_topo_lock) 91 #define SYSCON_TOPO_UNLOCK() sx_unlock(&syscon_topo_lock) 92 #define SYSCON_TOPO_ASSERT() sx_assert(&syscon_topo_lock, SA_LOCKED) 93 #define SYSCON_TOPO_XASSERT() sx_assert(&syscon_topo_lock, SA_XLOCKED) 94 95 /* 96 * Default syscon methods for base class. 97 */ 98 static int 99 syscon_method_init(struct syscon *syscon) 100 { 101 102 return (0); 103 }; 104 105 static int 106 syscon_method_uninit(struct syscon *syscon) 107 { 108 109 return (0); 110 }; 111 112 void * 113 syscon_get_softc(struct syscon *syscon) 114 { 115 116 return (syscon->softc); 117 }; 118 119 /* 120 * Create and initialize syscon object, but do not register it. 121 */ 122 struct syscon * 123 syscon_create(device_t pdev, syscon_class_t syscon_class) 124 { 125 struct syscon *syscon; 126 127 /* Create object and initialize it. */ 128 syscon = malloc(sizeof(struct syscon), M_SYSCON, 129 M_WAITOK | M_ZERO); 130 kobj_init((kobj_t)syscon, (kobj_class_t)syscon_class); 131 132 /* Allocate softc if required. */ 133 if (syscon_class->size > 0) 134 syscon->softc = malloc(syscon_class->size, M_SYSCON, 135 M_WAITOK | M_ZERO); 136 137 /* Rest of init. */ 138 syscon->pdev = pdev; 139 return (syscon); 140 } 141 142 /* Register syscon object. */ 143 struct syscon * 144 syscon_register(struct syscon *syscon) 145 { 146 int rv; 147 148 #ifdef FDT 149 if (syscon->ofw_node <= 0) 150 syscon->ofw_node = ofw_bus_get_node(syscon->pdev); 151 if (syscon->ofw_node <= 0) 152 return (NULL); 153 #endif 154 155 rv = SYSCON_INIT(syscon); 156 if (rv != 0) { 157 printf("SYSCON_INIT failed: %d\n", rv); 158 return (NULL); 159 } 160 161 #ifdef FDT 162 OF_device_register_xref(OF_xref_from_node(syscon->ofw_node), 163 syscon->pdev); 164 #endif 165 SYSCON_TOPO_XLOCK(); 166 TAILQ_INSERT_TAIL(&syscon_list, syscon, syscon_link); 167 SYSCON_TOPO_UNLOCK(); 168 return (syscon); 169 } 170 171 int 172 syscon_unregister(struct syscon *syscon) 173 { 174 175 SYSCON_TOPO_XLOCK(); 176 TAILQ_REMOVE(&syscon_list, syscon, syscon_link); 177 SYSCON_TOPO_UNLOCK(); 178 #ifdef FDT 179 OF_device_register_xref(OF_xref_from_node(syscon->ofw_node), NULL); 180 #endif 181 return (SYSCON_UNINIT(syscon)); 182 } 183 184 /** 185 * Provider methods 186 */ 187 #ifdef FDT 188 static struct syscon * 189 syscon_find_by_ofw_node(phandle_t node) 190 { 191 struct syscon *entry; 192 193 SYSCON_TOPO_ASSERT(); 194 195 TAILQ_FOREACH(entry, &syscon_list, syscon_link) { 196 if (entry->ofw_node == node) 197 return (entry); 198 } 199 200 return (NULL); 201 } 202 203 struct syscon * 204 syscon_create_ofw_node(device_t pdev, syscon_class_t syscon_class, 205 phandle_t node) 206 { 207 struct syscon *syscon; 208 209 syscon = syscon_create(pdev, syscon_class); 210 if (syscon == NULL) 211 return (NULL); 212 syscon->ofw_node = node; 213 if (syscon_register(syscon) == NULL) 214 return (NULL); 215 return (syscon); 216 } 217 218 phandle_t 219 syscon_get_ofw_node(struct syscon *syscon) 220 { 221 222 return (syscon->ofw_node); 223 } 224 225 int 226 syscon_get_by_ofw_property(device_t cdev, phandle_t cnode, char *name, 227 struct syscon **syscon) 228 { 229 pcell_t *cells; 230 int ncells; 231 232 if (cnode <= 0) 233 cnode = ofw_bus_get_node(cdev); 234 if (cnode <= 0) { 235 device_printf(cdev, 236 "%s called on not ofw based device\n", __func__); 237 return (ENXIO); 238 } 239 ncells = OF_getencprop_alloc(cnode, name, sizeof(pcell_t), 240 (void **)&cells); 241 if (ncells < 1) 242 return (ENXIO); 243 244 /* Translate to syscon node. */ 245 SYSCON_TOPO_SLOCK(); 246 *syscon = syscon_find_by_ofw_node(OF_node_from_xref(cells[0])); 247 if (*syscon == NULL) { 248 SYSCON_TOPO_UNLOCK(); 249 device_printf(cdev, "Failed to find syscon node\n"); 250 OF_prop_free(cells); 251 return (ENODEV); 252 } 253 SYSCON_TOPO_UNLOCK(); 254 OF_prop_free(cells); 255 return (0); 256 } 257 #endif 258