1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * Taken from Linux v4.9 drivers/of/address.c 4 * 5 * Modified for U-Boot 6 * Copyright (c) 2017 Google, Inc 7 */ 8 9 #include <common.h> 10 #include <linux/libfdt.h> 11 #include <dm/of_access.h> 12 #include <dm/of_addr.h> 13 #include <linux/err.h> 14 #include <linux/ioport.h> 15 16 /* Max address size we deal with */ 17 #define OF_MAX_ADDR_CELLS 4 18 #define OF_CHECK_ADDR_COUNT(na) ((na) > 0 && (na) <= OF_MAX_ADDR_CELLS) 19 #define OF_CHECK_COUNTS(na, ns) (OF_CHECK_ADDR_COUNT(na) && (ns) > 0) 20 21 static struct of_bus *of_match_bus(struct device_node *np); 22 23 /* Debug utility */ 24 #ifdef DEBUG 25 static void of_dump_addr(const char *s, const __be32 *addr, int na) 26 { 27 debug("%s", s); 28 while (na--) 29 pr_cont(" %08x", be32_to_cpu(*(addr++))); 30 pr_cont("\n"); 31 } 32 #else 33 static void of_dump_addr(const char *s, const __be32 *addr, int na) { } 34 #endif 35 36 /* Callbacks for bus specific translators */ 37 struct of_bus { 38 const char *name; 39 const char *addresses; 40 int (*match)(struct device_node *parent); 41 void (*count_cells)(const struct device_node *child, int *addrc, 42 int *sizec); 43 u64 (*map)(__be32 *addr, const __be32 *range, int na, int ns, int pna); 44 int (*translate)(__be32 *addr, u64 offset, int na); 45 unsigned int (*get_flags)(const __be32 *addr); 46 }; 47 48 static void of_bus_default_count_cells(const struct device_node *np, 49 int *addrc, int *sizec) 50 { 51 if (addrc) 52 *addrc = of_n_addr_cells(np); 53 if (sizec) 54 *sizec = of_n_size_cells(np); 55 } 56 57 static u64 of_bus_default_map(__be32 *addr, const __be32 *range, 58 int na, int ns, int pna) 59 { 60 u64 cp, s, da; 61 62 cp = of_read_number(range, na); 63 s = of_read_number(range + na + pna, ns); 64 da = of_read_number(addr, na); 65 66 debug("default map, cp=%llx, s=%llx, da=%llx\n", 67 (unsigned long long)cp, (unsigned long long)s, 68 (unsigned long long)da); 69 70 if (da < cp || da >= (cp + s)) 71 return OF_BAD_ADDR; 72 return da - cp; 73 } 74 75 static int of_bus_default_translate(__be32 *addr, u64 offset, int na) 76 { 77 u64 a = of_read_number(addr, na); 78 memset(addr, 0, na * 4); 79 a += offset; 80 if (na > 1) 81 addr[na - 2] = cpu_to_be32(a >> 32); 82 addr[na - 1] = cpu_to_be32(a & 0xffffffffu); 83 84 return 0; 85 } 86 87 static unsigned int of_bus_default_get_flags(const __be32 *addr) 88 { 89 return IORESOURCE_MEM; 90 } 91 92 /* 93 * Array of bus-specific translators 94 */ 95 static struct of_bus of_busses[] = { 96 /* Default */ 97 { 98 .name = "default", 99 .addresses = "reg", 100 .match = NULL, 101 .count_cells = of_bus_default_count_cells, 102 .map = of_bus_default_map, 103 .translate = of_bus_default_translate, 104 .get_flags = of_bus_default_get_flags, 105 }, 106 }; 107 108 static struct of_bus *of_match_bus(struct device_node *np) 109 { 110 int i; 111 112 for (i = 0; i < ARRAY_SIZE(of_busses); i++) 113 if (!of_busses[i].match || of_busses[i].match(np)) 114 return &of_busses[i]; 115 BUG(); 116 return NULL; 117 } 118 119 static void dev_count_cells(const struct device_node *np, int *nap, int *nsp) 120 { 121 of_bus_default_count_cells(np, nap, nsp); 122 } 123 124 const __be32 *of_get_address(const struct device_node *dev, int index, 125 u64 *size, unsigned int *flags) 126 { 127 const __be32 *prop; 128 int psize; 129 struct device_node *parent; 130 struct of_bus *bus; 131 int onesize, i, na, ns; 132 133 /* Get parent & match bus type */ 134 parent = of_get_parent(dev); 135 if (parent == NULL) 136 return NULL; 137 dev_count_cells(dev, &na, &ns); 138 bus = of_match_bus(parent); 139 bus->count_cells(dev, &na, &ns); 140 of_node_put(parent); 141 if (!OF_CHECK_ADDR_COUNT(na)) 142 return NULL; 143 144 /* Get "reg" or "assigned-addresses" property */ 145 prop = of_get_property(dev, "reg", &psize); 146 if (prop == NULL) 147 return NULL; 148 psize /= 4; 149 150 onesize = na + ns; 151 for (i = 0; psize >= onesize; psize -= onesize, prop += onesize, i++) 152 if (i == index) { 153 if (size) 154 *size = of_read_number(prop + na, ns); 155 if (flags) 156 *flags = bus->get_flags(prop); 157 return prop; 158 } 159 return NULL; 160 } 161 EXPORT_SYMBOL(of_get_address); 162 163 static int of_empty_ranges_quirk(const struct device_node *np) 164 { 165 return false; 166 } 167 168 static int of_translate_one(const struct device_node *parent, 169 struct of_bus *bus, struct of_bus *pbus, 170 __be32 *addr, int na, int ns, int pna, 171 const char *rprop) 172 { 173 const __be32 *ranges; 174 int rlen; 175 int rone; 176 u64 offset = OF_BAD_ADDR; 177 178 /* 179 * Normally, an absence of a "ranges" property means we are 180 * crossing a non-translatable boundary, and thus the addresses 181 * below the current cannot be converted to CPU physical ones. 182 * Unfortunately, while this is very clear in the spec, it's not 183 * what Apple understood, and they do have things like /uni-n or 184 * /ht nodes with no "ranges" property and a lot of perfectly 185 * useable mapped devices below them. Thus we treat the absence of 186 * "ranges" as equivalent to an empty "ranges" property which means 187 * a 1:1 translation at that level. It's up to the caller not to try 188 * to translate addresses that aren't supposed to be translated in 189 * the first place. --BenH. 190 * 191 * As far as we know, this damage only exists on Apple machines, so 192 * This code is only enabled on powerpc. --gcl 193 */ 194 ranges = of_get_property(parent, rprop, &rlen); 195 if (ranges == NULL && !of_empty_ranges_quirk(parent)) { 196 debug("no ranges; cannot translate\n"); 197 return 1; 198 } 199 if (ranges == NULL || rlen == 0) { 200 offset = of_read_number(addr, na); 201 memset(addr, 0, pna * 4); 202 debug("empty ranges; 1:1 translation\n"); 203 goto finish; 204 } 205 206 debug("walking ranges...\n"); 207 208 /* Now walk through the ranges */ 209 rlen /= 4; 210 rone = na + pna + ns; 211 for (; rlen >= rone; rlen -= rone, ranges += rone) { 212 offset = bus->map(addr, ranges, na, ns, pna); 213 if (offset != OF_BAD_ADDR) 214 break; 215 } 216 if (offset == OF_BAD_ADDR) { 217 debug("not found !\n"); 218 return 1; 219 } 220 memcpy(addr, ranges + na, 4 * pna); 221 222 finish: 223 of_dump_addr("parent translation for:", addr, pna); 224 debug("with offset: %llx\n", (unsigned long long)offset); 225 226 /* Translate it into parent bus space */ 227 return pbus->translate(addr, offset, pna); 228 } 229 230 /* 231 * Translate an address from the device-tree into a CPU physical address, 232 * this walks up the tree and applies the various bus mappings on the 233 * way. 234 * 235 * Note: We consider that crossing any level with #size-cells == 0 to mean 236 * that translation is impossible (that is we are not dealing with a value 237 * that can be mapped to a cpu physical address). This is not really specified 238 * that way, but this is traditionally the way IBM at least do things 239 */ 240 static u64 __of_translate_address(const struct device_node *dev, 241 const __be32 *in_addr, const char *rprop) 242 { 243 struct device_node *parent = NULL; 244 struct of_bus *bus, *pbus; 245 __be32 addr[OF_MAX_ADDR_CELLS]; 246 int na, ns, pna, pns; 247 u64 result = OF_BAD_ADDR; 248 249 debug("** translation for device %s **\n", of_node_full_name(dev)); 250 251 /* Increase refcount at current level */ 252 (void)of_node_get(dev); 253 254 /* Get parent & match bus type */ 255 parent = of_get_parent(dev); 256 if (parent == NULL) 257 goto bail; 258 bus = of_match_bus(parent); 259 260 /* Count address cells & copy address locally */ 261 bus->count_cells(dev, &na, &ns); 262 if (!OF_CHECK_COUNTS(na, ns)) { 263 debug("Bad cell count for %s\n", of_node_full_name(dev)); 264 goto bail; 265 } 266 memcpy(addr, in_addr, na * 4); 267 268 debug("bus is %s (na=%d, ns=%d) on %s\n", bus->name, na, ns, 269 of_node_full_name(parent)); 270 of_dump_addr("translating address:", addr, na); 271 272 /* Translate */ 273 for (;;) { 274 /* Switch to parent bus */ 275 of_node_put(dev); 276 dev = parent; 277 parent = of_get_parent(dev); 278 279 /* If root, we have finished */ 280 if (parent == NULL) { 281 debug("reached root node\n"); 282 result = of_read_number(addr, na); 283 break; 284 } 285 286 /* Get new parent bus and counts */ 287 pbus = of_match_bus(parent); 288 pbus->count_cells(dev, &pna, &pns); 289 if (!OF_CHECK_COUNTS(pna, pns)) { 290 debug("Bad cell count for %s\n", 291 of_node_full_name(dev)); 292 break; 293 } 294 295 debug("parent bus is %s (na=%d, ns=%d) on %s\n", pbus->name, 296 pna, pns, of_node_full_name(parent)); 297 298 /* Apply bus translation */ 299 if (of_translate_one(dev, bus, pbus, addr, na, ns, pna, rprop)) 300 break; 301 302 /* Complete the move up one level */ 303 na = pna; 304 ns = pns; 305 bus = pbus; 306 307 of_dump_addr("one level translation:", addr, na); 308 } 309 bail: 310 of_node_put(parent); 311 of_node_put(dev); 312 313 return result; 314 } 315 316 u64 of_translate_address(const struct device_node *dev, const __be32 *in_addr) 317 { 318 return __of_translate_address(dev, in_addr, "ranges"); 319 } 320 321 322 static int __of_address_to_resource(const struct device_node *dev, 323 const __be32 *addrp, u64 size, unsigned int flags, 324 const char *name, struct resource *r) 325 { 326 u64 taddr; 327 328 if ((flags & (IORESOURCE_IO | IORESOURCE_MEM)) == 0) 329 return -EINVAL; 330 taddr = of_translate_address(dev, addrp); 331 if (taddr == OF_BAD_ADDR) 332 return -EINVAL; 333 memset(r, 0, sizeof(struct resource)); 334 r->start = taddr; 335 r->end = taddr + size - 1; 336 r->flags = flags; 337 r->name = name ? name : dev->full_name; 338 339 return 0; 340 } 341 342 int of_address_to_resource(const struct device_node *dev, int index, 343 struct resource *r) 344 { 345 const __be32 *addrp; 346 u64 size; 347 unsigned int flags; 348 const char *name = NULL; 349 350 addrp = of_get_address(dev, index, &size, &flags); 351 if (addrp == NULL) 352 return -EINVAL; 353 354 /* Get optional "reg-names" property to add a name to a resource */ 355 of_property_read_string_index(dev, "reg-names", index, &name); 356 357 return __of_address_to_resource(dev, addrp, size, flags, name, r); 358 } 359