1 /* 2 * Taken from Linux v4.9 drivers/of/address.c 3 * 4 * Modified for U-Boot 5 * Copyright (c) 2017 Google, Inc 6 * 7 * SPDX-License-Identifier: GPL-2.0+ 8 */ 9 10 #include <common.h> 11 #include <libfdt.h> 12 #include <dm/of_access.h> 13 #include <dm/of_addr.h> 14 #include <linux/err.h> 15 #include <linux/ioport.h> 16 17 /* Max address size we deal with */ 18 #define OF_MAX_ADDR_CELLS 4 19 #define OF_CHECK_ADDR_COUNT(na) ((na) > 0 && (na) <= OF_MAX_ADDR_CELLS) 20 #define OF_CHECK_COUNTS(na, ns) (OF_CHECK_ADDR_COUNT(na) && (ns) > 0) 21 22 static struct of_bus *of_match_bus(struct device_node *np); 23 24 /* Debug utility */ 25 #ifdef DEBUG 26 static void of_dump_addr(const char *s, const __be32 *addr, int na) 27 { 28 debug("%s", s); 29 while (na--) 30 pr_cont(" %08x", be32_to_cpu(*(addr++))); 31 pr_cont("\n"); 32 } 33 #else 34 static void of_dump_addr(const char *s, const __be32 *addr, int na) { } 35 #endif 36 37 /* Callbacks for bus specific translators */ 38 struct of_bus { 39 const char *name; 40 const char *addresses; 41 int (*match)(struct device_node *parent); 42 void (*count_cells)(const struct device_node *child, int *addrc, 43 int *sizec); 44 u64 (*map)(__be32 *addr, const __be32 *range, int na, int ns, int pna); 45 int (*translate)(__be32 *addr, u64 offset, int na); 46 unsigned int (*get_flags)(const __be32 *addr); 47 }; 48 49 static void of_bus_default_count_cells(const struct device_node *np, 50 int *addrc, int *sizec) 51 { 52 if (addrc) 53 *addrc = of_n_addr_cells(np); 54 if (sizec) 55 *sizec = of_n_size_cells(np); 56 } 57 58 static u64 of_bus_default_map(__be32 *addr, const __be32 *range, 59 int na, int ns, int pna) 60 { 61 u64 cp, s, da; 62 63 cp = of_read_number(range, na); 64 s = of_read_number(range + na + pna, ns); 65 da = of_read_number(addr, na); 66 67 debug("default map, cp=%llx, s=%llx, da=%llx\n", 68 (unsigned long long)cp, (unsigned long long)s, 69 (unsigned long long)da); 70 71 if (da < cp || da >= (cp + s)) 72 return OF_BAD_ADDR; 73 return da - cp; 74 } 75 76 static int of_bus_default_translate(__be32 *addr, u64 offset, int na) 77 { 78 u64 a = of_read_number(addr, na); 79 memset(addr, 0, na * 4); 80 a += offset; 81 if (na > 1) 82 addr[na - 2] = cpu_to_be32(a >> 32); 83 addr[na - 1] = cpu_to_be32(a & 0xffffffffu); 84 85 return 0; 86 } 87 88 static unsigned int of_bus_default_get_flags(const __be32 *addr) 89 { 90 return IORESOURCE_MEM; 91 } 92 93 /* 94 * Array of bus-specific translators 95 */ 96 static struct of_bus of_busses[] = { 97 /* Default */ 98 { 99 .name = "default", 100 .addresses = "reg", 101 .match = NULL, 102 .count_cells = of_bus_default_count_cells, 103 .map = of_bus_default_map, 104 .translate = of_bus_default_translate, 105 .get_flags = of_bus_default_get_flags, 106 }, 107 }; 108 109 static struct of_bus *of_match_bus(struct device_node *np) 110 { 111 int i; 112 113 for (i = 0; i < ARRAY_SIZE(of_busses); i++) 114 if (!of_busses[i].match || of_busses[i].match(np)) 115 return &of_busses[i]; 116 BUG(); 117 return NULL; 118 } 119 120 static void dev_count_cells(const struct device_node *np, int *nap, int *nsp) 121 { 122 of_bus_default_count_cells(np, nap, nsp); 123 } 124 125 const __be32 *of_get_address(const struct device_node *dev, int index, 126 u64 *size, unsigned int *flags) 127 { 128 const __be32 *prop; 129 int psize; 130 struct device_node *parent; 131 struct of_bus *bus; 132 int onesize, i, na, ns; 133 134 /* Get parent & match bus type */ 135 parent = of_get_parent(dev); 136 if (parent == NULL) 137 return NULL; 138 dev_count_cells(dev, &na, &ns); 139 bus = of_match_bus(parent); 140 bus->count_cells(dev, &na, &ns); 141 of_node_put(parent); 142 if (!OF_CHECK_ADDR_COUNT(na)) 143 return NULL; 144 145 /* Get "reg" or "assigned-addresses" property */ 146 prop = of_get_property(dev, "reg", &psize); 147 if (prop == NULL) 148 return NULL; 149 psize /= 4; 150 151 onesize = na + ns; 152 for (i = 0; psize >= onesize; psize -= onesize, prop += onesize, i++) 153 if (i == index) { 154 if (size) 155 *size = of_read_number(prop + na, ns); 156 if (flags) 157 *flags = bus->get_flags(prop); 158 return prop; 159 } 160 return NULL; 161 } 162 EXPORT_SYMBOL(of_get_address); 163 164 static int of_empty_ranges_quirk(const struct device_node *np) 165 { 166 return false; 167 } 168 169 static int of_translate_one(const struct device_node *parent, 170 struct of_bus *bus, struct of_bus *pbus, 171 __be32 *addr, int na, int ns, int pna, 172 const char *rprop) 173 { 174 const __be32 *ranges; 175 int rlen; 176 int rone; 177 u64 offset = OF_BAD_ADDR; 178 179 /* 180 * Normally, an absence of a "ranges" property means we are 181 * crossing a non-translatable boundary, and thus the addresses 182 * below the current cannot be converted to CPU physical ones. 183 * Unfortunately, while this is very clear in the spec, it's not 184 * what Apple understood, and they do have things like /uni-n or 185 * /ht nodes with no "ranges" property and a lot of perfectly 186 * useable mapped devices below them. Thus we treat the absence of 187 * "ranges" as equivalent to an empty "ranges" property which means 188 * a 1:1 translation at that level. It's up to the caller not to try 189 * to translate addresses that aren't supposed to be translated in 190 * the first place. --BenH. 191 * 192 * As far as we know, this damage only exists on Apple machines, so 193 * This code is only enabled on powerpc. --gcl 194 */ 195 ranges = of_get_property(parent, rprop, &rlen); 196 if (ranges == NULL && !of_empty_ranges_quirk(parent)) { 197 debug("no ranges; cannot translate\n"); 198 return 1; 199 } 200 if (ranges == NULL || rlen == 0) { 201 offset = of_read_number(addr, na); 202 memset(addr, 0, pna * 4); 203 debug("empty ranges; 1:1 translation\n"); 204 goto finish; 205 } 206 207 debug("walking ranges...\n"); 208 209 /* Now walk through the ranges */ 210 rlen /= 4; 211 rone = na + pna + ns; 212 for (; rlen >= rone; rlen -= rone, ranges += rone) { 213 offset = bus->map(addr, ranges, na, ns, pna); 214 if (offset != OF_BAD_ADDR) 215 break; 216 } 217 if (offset == OF_BAD_ADDR) { 218 debug("not found !\n"); 219 return 1; 220 } 221 memcpy(addr, ranges + na, 4 * pna); 222 223 finish: 224 of_dump_addr("parent translation for:", addr, pna); 225 debug("with offset: %llx\n", (unsigned long long)offset); 226 227 /* Translate it into parent bus space */ 228 return pbus->translate(addr, offset, pna); 229 } 230 231 /* 232 * Translate an address from the device-tree into a CPU physical address, 233 * this walks up the tree and applies the various bus mappings on the 234 * way. 235 * 236 * Note: We consider that crossing any level with #size-cells == 0 to mean 237 * that translation is impossible (that is we are not dealing with a value 238 * that can be mapped to a cpu physical address). This is not really specified 239 * that way, but this is traditionally the way IBM at least do things 240 */ 241 static u64 __of_translate_address(const struct device_node *dev, 242 const __be32 *in_addr, const char *rprop) 243 { 244 struct device_node *parent = NULL; 245 struct of_bus *bus, *pbus; 246 __be32 addr[OF_MAX_ADDR_CELLS]; 247 int na, ns, pna, pns; 248 u64 result = OF_BAD_ADDR; 249 250 debug("** translation for device %s **\n", of_node_full_name(dev)); 251 252 /* Increase refcount at current level */ 253 (void)of_node_get(dev); 254 255 /* Get parent & match bus type */ 256 parent = of_get_parent(dev); 257 if (parent == NULL) 258 goto bail; 259 bus = of_match_bus(parent); 260 261 /* Count address cells & copy address locally */ 262 bus->count_cells(dev, &na, &ns); 263 if (!OF_CHECK_COUNTS(na, ns)) { 264 debug("Bad cell count for %s\n", of_node_full_name(dev)); 265 goto bail; 266 } 267 memcpy(addr, in_addr, na * 4); 268 269 debug("bus is %s (na=%d, ns=%d) on %s\n", bus->name, na, ns, 270 of_node_full_name(parent)); 271 of_dump_addr("translating address:", addr, na); 272 273 /* Translate */ 274 for (;;) { 275 /* Switch to parent bus */ 276 of_node_put(dev); 277 dev = parent; 278 parent = of_get_parent(dev); 279 280 /* If root, we have finished */ 281 if (parent == NULL) { 282 debug("reached root node\n"); 283 result = of_read_number(addr, na); 284 break; 285 } 286 287 /* Get new parent bus and counts */ 288 pbus = of_match_bus(parent); 289 pbus->count_cells(dev, &pna, &pns); 290 if (!OF_CHECK_COUNTS(pna, pns)) { 291 debug("Bad cell count for %s\n", 292 of_node_full_name(dev)); 293 break; 294 } 295 296 debug("parent bus is %s (na=%d, ns=%d) on %s\n", pbus->name, 297 pna, pns, of_node_full_name(parent)); 298 299 /* Apply bus translation */ 300 if (of_translate_one(dev, bus, pbus, addr, na, ns, pna, rprop)) 301 break; 302 303 /* Complete the move up one level */ 304 na = pna; 305 ns = pns; 306 bus = pbus; 307 308 of_dump_addr("one level translation:", addr, na); 309 } 310 bail: 311 of_node_put(parent); 312 of_node_put(dev); 313 314 return result; 315 } 316 317 u64 of_translate_address(const struct device_node *dev, const __be32 *in_addr) 318 { 319 return __of_translate_address(dev, in_addr, "ranges"); 320 } 321 322 323 static int __of_address_to_resource(const struct device_node *dev, 324 const __be32 *addrp, u64 size, unsigned int flags, 325 const char *name, struct resource *r) 326 { 327 u64 taddr; 328 329 if ((flags & (IORESOURCE_IO | IORESOURCE_MEM)) == 0) 330 return -EINVAL; 331 taddr = of_translate_address(dev, addrp); 332 if (taddr == OF_BAD_ADDR) 333 return -EINVAL; 334 memset(r, 0, sizeof(struct resource)); 335 r->start = taddr; 336 r->end = taddr + size - 1; 337 r->flags = flags; 338 r->name = name ? name : dev->full_name; 339 340 return 0; 341 } 342 343 int of_address_to_resource(const struct device_node *dev, int index, 344 struct resource *r) 345 { 346 const __be32 *addrp; 347 u64 size; 348 unsigned int flags; 349 const char *name = NULL; 350 351 addrp = of_get_address(dev, index, &size, &flags); 352 if (addrp == NULL) 353 return -EINVAL; 354 355 /* Get optional "reg-names" property to add a name to a resource */ 356 of_property_read_string_index(dev, "reg-names", index, &name); 357 358 return __of_address_to_resource(dev, addrp, size, flags, name, r); 359 } 360