1/*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2017 Kyle Evans <kevans@FreeBSD.org> 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 */ 63typedef TAILQ_HEAD(syscon_list, syscon) syscon_list_t; 64 65/* 66 * Declarations 67 */ 68static int syscon_method_init(struct syscon *syscon); 69static int syscon_method_uninit(struct syscon *syscon); 70static uint32_t syscon_method_read_4(struct syscon *syscon, bus_size_t offset); 71static int syscon_method_write_4(struct syscon *syscon, bus_size_t offset, 72 uint32_t val); 73static int syscon_method_modify_4(struct syscon *syscon, bus_size_t offset, 74 uint32_t clear_bits, uint32_t set_bits); 75 76 77MALLOC_DEFINE(M_SYSCON, "syscon", "Syscon driver"); 78 79static syscon_list_t syscon_list = TAILQ_HEAD_INITIALIZER(syscon_list); 80static struct sx syscon_topo_lock; 81SX_SYSINIT(syscon_topology, &syscon_topo_lock, "Syscon topology lock"); 82 83/* 84 * Syscon methods. 85 */ 86static syscon_method_t syscon_methods[] = { 87 SYSCONMETHOD(syscon_init, syscon_method_init), 88 SYSCONMETHOD(syscon_uninit, syscon_method_uninit), 89 SYSCONMETHOD(syscon_read_4, syscon_method_read_4), 90 SYSCONMETHOD(syscon_write_4, syscon_method_write_4), 91 SYSCONMETHOD(syscon_modify_4, syscon_method_modify_4), 92 93 SYSCONMETHOD_END 94}; 95DEFINE_CLASS_0(syscon, syscon_class, syscon_methods, 0); 96 97#define SYSCON_TOPO_SLOCK() sx_slock(&syscon_topo_lock) 98#define SYSCON_TOPO_XLOCK() sx_xlock(&syscon_topo_lock) 99#define SYSCON_TOPO_UNLOCK() sx_unlock(&syscon_topo_lock) 100#define SYSCON_TOPO_ASSERT() sx_assert(&syscon_topo_lock, SA_LOCKED) 101#define SYSCON_TOPO_XASSERT() sx_assert(&syscon_topo_lock, SA_XLOCKED) 102 103/* 104 * Default syscon methods for base class. 105 */ 106static int 107syscon_method_init(struct syscon *syscon) 108{ 109 110 return (0); 111}; 112 113static int 114syscon_method_uninit(struct syscon *syscon) 115{ 116 117 return (0); 118}; 119 120void * 121syscon_get_softc(struct syscon *syscon) 122{ 123 124 return (syscon->softc); 125}; 126 127static uint32_t 128syscon_method_read_4(struct syscon *syscon, bus_size_t offset) 129{ 130 uint32_t val; 131 132 SYSCON_DEVICE_LOCK(syscon->pdev); 133 val = SYSCON_UNLOCKED_READ_4(syscon, offset); 134 SYSCON_DEVICE_UNLOCK(syscon->pdev); 135 return(val); 136} 137 138static int 139syscon_method_write_4(struct syscon *syscon, bus_size_t offset, uint32_t val) 140{ 141 int rv; 142 143 SYSCON_DEVICE_LOCK(syscon->pdev); 144 rv = SYSCON_UNLOCKED_WRITE_4(syscon, offset, val); 145 SYSCON_DEVICE_UNLOCK(syscon->pdev); 146 return(rv); 147} 148 149static int 150syscon_method_modify_4(struct syscon *syscon, bus_size_t offset, 151 uint32_t clear_bits, uint32_t set_bits) 152{ 153 int rv; 154 155 SYSCON_DEVICE_LOCK(syscon->pdev); 156 rv = SYSCON_UNLOCKED_MODIFY_4(syscon, offset, clear_bits, set_bits); 157 SYSCON_DEVICE_UNLOCK(syscon->pdev); 158 return(rv); 159} 160/* 161 * Create and initialize syscon object, but do not register it. 162 */ 163struct syscon * 164syscon_create(device_t pdev, syscon_class_t syscon_class) 165{ 166 struct syscon *syscon; 167 168 /* Create object and initialize it. */ 169 syscon = malloc(sizeof(struct syscon), M_SYSCON, 170 M_WAITOK | M_ZERO); 171 kobj_init((kobj_t)syscon, (kobj_class_t)syscon_class); 172 173 /* Allocate softc if required. */ 174 if (syscon_class->size > 0) 175 syscon->softc = malloc(syscon_class->size, M_SYSCON, 176 M_WAITOK | M_ZERO); 177 178 /* Rest of init. */ 179 syscon->pdev = pdev; 180 return (syscon); 181} 182 183/* Register syscon object. */ 184struct syscon * 185syscon_register(struct syscon *syscon) 186{ 187 int rv; 188 189#ifdef FDT 190 if (syscon->ofw_node <= 0) 191 syscon->ofw_node = ofw_bus_get_node(syscon->pdev); 192 if (syscon->ofw_node <= 0) 193 return (NULL); 194#endif 195 196 rv = SYSCON_INIT(syscon); 197 if (rv != 0) { 198 printf("SYSCON_INIT failed: %d\n", rv); 199 return (NULL); 200 } 201 202#ifdef FDT 203 OF_device_register_xref(OF_xref_from_node(syscon->ofw_node), 204 syscon->pdev); 205#endif 206 SYSCON_TOPO_XLOCK(); 207 TAILQ_INSERT_TAIL(&syscon_list, syscon, syscon_link); 208 SYSCON_TOPO_UNLOCK(); 209 return (syscon); 210} 211 212int 213syscon_unregister(struct syscon *syscon) 214{ 215 216 SYSCON_TOPO_XLOCK(); 217 TAILQ_REMOVE(&syscon_list, syscon, syscon_link); 218 SYSCON_TOPO_UNLOCK(); 219#ifdef FDT 220 OF_device_register_xref(OF_xref_from_node(syscon->ofw_node), NULL); 221#endif 222 return (SYSCON_UNINIT(syscon)); 223} 224 225/** 226 * Provider methods 227 */ 228#ifdef FDT 229static struct syscon * 230syscon_find_by_ofw_node(phandle_t node) 231{ 232 struct syscon *entry; 233 234 SYSCON_TOPO_ASSERT(); 235 236 TAILQ_FOREACH(entry, &syscon_list, syscon_link) { 237 if (entry->ofw_node == node) 238 return (entry); 239 } 240 241 return (NULL); 242} 243 244struct syscon * 245syscon_create_ofw_node(device_t pdev, syscon_class_t syscon_class, 246 phandle_t node) 247{ 248 struct syscon *syscon; 249 250 syscon = syscon_create(pdev, syscon_class); 251 if (syscon == NULL) 252 return (NULL); 253 syscon->ofw_node = node; 254 if (syscon_register(syscon) == NULL) 255 return (NULL); 256 return (syscon); 257} 258 259phandle_t 260syscon_get_ofw_node(struct syscon *syscon) 261{ 262 263 return (syscon->ofw_node); 264} 265 266int 267syscon_get_by_ofw_property(device_t cdev, phandle_t cnode, char *name, 268 struct syscon **syscon) 269{ 270 pcell_t *cells; 271 int ncells; 272 273 if (cnode <= 0) 274 cnode = ofw_bus_get_node(cdev); 275 if (cnode <= 0) { 276 device_printf(cdev, 277 "%s called on not ofw based device\n", __func__); 278 return (ENXIO); 279 } 280 ncells = OF_getencprop_alloc_multi(cnode, name, sizeof(pcell_t), 281 (void **)&cells); 282 if (ncells < 1) 283 return (ENOENT); 284 285 /* Translate to syscon node. */ 286 SYSCON_TOPO_SLOCK(); 287 *syscon = syscon_find_by_ofw_node(OF_node_from_xref(cells[0])); 288 if (*syscon == NULL) { 289 SYSCON_TOPO_UNLOCK(); 290 device_printf(cdev, "Failed to find syscon node\n"); 291 OF_prop_free(cells); 292 return (ENODEV); 293 } 294 SYSCON_TOPO_UNLOCK(); 295 OF_prop_free(cells); 296 return (0); 297} 298#endif 299