1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2017 Kyle Evans <[email protected]> 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 */ 27 28 /* 29 * This is a generic syscon driver, whose purpose is to provide access to 30 * various unrelated bits packed in a single register space. It is usually used 31 * as a fallback to more specific driver, but works well enough for simple 32 * access. 33 */ 34 35 #include <sys/cdefs.h> 36 __FBSDID("$FreeBSD$"); 37 #include "opt_platform.h" 38 39 #include <sys/param.h> 40 #include <sys/systm.h> 41 #include <sys/bus.h> 42 #include <sys/kernel.h> 43 #include <sys/kobj.h> 44 #include <sys/lock.h> 45 #include <sys/module.h> 46 #include <sys/rman.h> 47 #include <sys/sx.h> 48 #include <sys/queue.h> 49 50 #include <machine/bus.h> 51 52 #ifdef FDT 53 #include <dev/ofw/ofw_bus.h> 54 #include <dev/ofw/ofw_bus_subr.h> 55 #endif 56 57 #include "syscon_if.h" 58 #include "syscon.h" 59 60 /* 61 * Syscon interface details 62 */ 63 typedef TAILQ_HEAD(syscon_list, syscon) syscon_list_t; 64 65 /* 66 * Declarations 67 */ 68 static int syscon_method_init(struct syscon *syscon); 69 static int syscon_method_uninit(struct syscon *syscon); 70 71 MALLOC_DEFINE(M_SYSCON, "syscon", "Syscon driver"); 72 73 static syscon_list_t syscon_list = TAILQ_HEAD_INITIALIZER(syscon_list); 74 static struct sx syscon_topo_lock; 75 SX_SYSINIT(syscon_topology, &syscon_topo_lock, "Syscon topology lock"); 76 77 /* 78 * Syscon methods. 79 */ 80 static syscon_method_t syscon_methods[] = { 81 SYSCONMETHOD(syscon_init, syscon_method_init), 82 SYSCONMETHOD(syscon_uninit, syscon_method_uninit), 83 84 SYSCONMETHOD_END 85 }; 86 DEFINE_CLASS_0(syscon, syscon_class, syscon_methods, 0); 87 88 #define SYSCON_TOPO_SLOCK() sx_slock(&syscon_topo_lock) 89 #define SYSCON_TOPO_XLOCK() sx_xlock(&syscon_topo_lock) 90 #define SYSCON_TOPO_UNLOCK() sx_unlock(&syscon_topo_lock) 91 #define SYSCON_TOPO_ASSERT() sx_assert(&syscon_topo_lock, SA_LOCKED) 92 #define SYSCON_TOPO_XASSERT() sx_assert(&syscon_topo_lock, SA_XLOCKED) 93 94 /* 95 * Default syscon methods for base class. 96 */ 97 static int 98 syscon_method_init(struct syscon *syscon) 99 { 100 101 return (0); 102 }; 103 104 static int 105 syscon_method_uninit(struct syscon *syscon) 106 { 107 108 return (0); 109 }; 110 111 void * 112 syscon_get_softc(struct syscon *syscon) 113 { 114 115 return (syscon->softc); 116 }; 117 118 /* 119 * Create and initialize syscon object, but do not register it. 120 */ 121 struct syscon * 122 syscon_create(device_t pdev, syscon_class_t syscon_class) 123 { 124 struct syscon *syscon; 125 126 /* Create object and initialize it. */ 127 syscon = malloc(sizeof(struct syscon), M_SYSCON, 128 M_WAITOK | M_ZERO); 129 kobj_init((kobj_t)syscon, (kobj_class_t)syscon_class); 130 131 /* Allocate softc if required. */ 132 if (syscon_class->size > 0) 133 syscon->softc = malloc(syscon_class->size, M_SYSCON, 134 M_WAITOK | M_ZERO); 135 136 /* Rest of init. */ 137 syscon->pdev = pdev; 138 return (syscon); 139 } 140 141 /* Register syscon object. */ 142 struct syscon * 143 syscon_register(struct syscon *syscon) 144 { 145 int rv; 146 147 #ifdef FDT 148 if (syscon->ofw_node <= 0) 149 syscon->ofw_node = ofw_bus_get_node(syscon->pdev); 150 if (syscon->ofw_node <= 0) 151 return (NULL); 152 #endif 153 154 rv = SYSCON_INIT(syscon); 155 if (rv != 0) { 156 printf("SYSCON_INIT failed: %d\n", rv); 157 return (NULL); 158 } 159 160 #ifdef FDT 161 OF_device_register_xref(OF_xref_from_node(syscon->ofw_node), 162 syscon->pdev); 163 #endif 164 SYSCON_TOPO_XLOCK(); 165 TAILQ_INSERT_TAIL(&syscon_list, syscon, syscon_link); 166 SYSCON_TOPO_UNLOCK(); 167 return (syscon); 168 } 169 170 int 171 syscon_unregister(struct syscon *syscon) 172 { 173 174 SYSCON_TOPO_XLOCK(); 175 TAILQ_REMOVE(&syscon_list, syscon, syscon_link); 176 SYSCON_TOPO_UNLOCK(); 177 #ifdef FDT 178 OF_device_register_xref(OF_xref_from_node(syscon->ofw_node), NULL); 179 #endif 180 return (SYSCON_UNINIT(syscon)); 181 } 182 183 /** 184 * Provider methods 185 */ 186 #ifdef FDT 187 static struct syscon * 188 syscon_find_by_ofw_node(phandle_t node) 189 { 190 struct syscon *entry; 191 192 SYSCON_TOPO_ASSERT(); 193 194 TAILQ_FOREACH(entry, &syscon_list, syscon_link) { 195 if (entry->ofw_node == node) 196 return (entry); 197 } 198 199 return (NULL); 200 } 201 202 struct syscon * 203 syscon_create_ofw_node(device_t pdev, syscon_class_t syscon_class, 204 phandle_t node) 205 { 206 struct syscon *syscon; 207 208 syscon = syscon_create(pdev, syscon_class); 209 if (syscon == NULL) 210 return (NULL); 211 syscon->ofw_node = node; 212 if (syscon_register(syscon) == NULL) 213 return (NULL); 214 return (syscon); 215 } 216 217 phandle_t 218 syscon_get_ofw_node(struct syscon *syscon) 219 { 220 221 return (syscon->ofw_node); 222 } 223 224 int 225 syscon_get_by_ofw_property(device_t cdev, phandle_t cnode, char *name, 226 struct syscon **syscon) 227 { 228 pcell_t *cells; 229 int ncells; 230 231 if (cnode <= 0) 232 cnode = ofw_bus_get_node(cdev); 233 if (cnode <= 0) { 234 device_printf(cdev, 235 "%s called on not ofw based device\n", __func__); 236 return (ENXIO); 237 } 238 ncells = OF_getencprop_alloc_multi(cnode, name, sizeof(pcell_t), 239 (void **)&cells); 240 if (ncells < 1) 241 return (ENOENT); 242 243 /* Translate to syscon node. */ 244 SYSCON_TOPO_SLOCK(); 245 *syscon = syscon_find_by_ofw_node(OF_node_from_xref(cells[0])); 246 if (*syscon == NULL) { 247 SYSCON_TOPO_UNLOCK(); 248 device_printf(cdev, "Failed to find syscon node\n"); 249 OF_prop_free(cells); 250 return (ENODEV); 251 } 252 SYSCON_TOPO_UNLOCK(); 253 OF_prop_free(cells); 254 return (0); 255 } 256 #endif 257