1 /* 2 * Copyright (c) 2013-2014, ARM Limited and Contributors. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions are met: 6 * 7 * Redistributions of source code must retain the above copyright notice, this 8 * list of conditions and the following disclaimer. 9 * 10 * Redistributions in binary form must reproduce the above copyright notice, 11 * this list of conditions and the following disclaimer in the documentation 12 * and/or other materials provided with the distribution. 13 * 14 * Neither the name of ARM nor the names of its contributors may be used 15 * to endorse or promote products derived from this software without specific 16 * prior written permission. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 19 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE 22 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 23 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 24 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 25 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 26 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 27 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 28 * POSSIBILITY OF SUCH DAMAGE. 29 */ 30 31 #include <arch.h> 32 #include <arch_helpers.h> 33 #include <assert.h> 34 #include <bl_common.h> 35 #include <debug.h> 36 #include <io_storage.h> 37 #include <platform.h> 38 #include <errno.h> 39 #include <stdio.h> 40 41 unsigned long page_align(unsigned long value, unsigned dir) 42 { 43 unsigned long page_size = 1 << FOUR_KB_SHIFT; 44 45 /* Round up the limit to the next page boundary */ 46 if (value & (page_size - 1)) { 47 value &= ~(page_size - 1); 48 if (dir == UP) 49 value += page_size; 50 } 51 52 return value; 53 } 54 55 static inline unsigned int is_page_aligned (unsigned long addr) { 56 const unsigned long page_size = 1 << FOUR_KB_SHIFT; 57 58 return (addr & (page_size - 1)) == 0; 59 } 60 61 void change_security_state(unsigned int target_security_state) 62 { 63 unsigned long scr = read_scr(); 64 65 if (target_security_state == SECURE) 66 scr &= ~SCR_NS_BIT; 67 else if (target_security_state == NON_SECURE) 68 scr |= SCR_NS_BIT; 69 else 70 assert(0); 71 72 write_scr(scr); 73 } 74 75 76 /******************************************************************************* 77 * The next function is a weak definition. Platform specific 78 * code can override it if it wishes to. 79 ******************************************************************************/ 80 81 /******************************************************************************* 82 * Function that takes a memory layout into which BL2 has been either top or 83 * bottom loaded along with the address where BL2 has been loaded in it. Using 84 * this information, it populates bl2_mem_layout to tell BL2 how much memory 85 * it has access to and how much is available for use. 86 ******************************************************************************/ 87 void init_bl2_mem_layout(meminfo_t *bl1_mem_layout, 88 meminfo_t *bl2_mem_layout, 89 unsigned int load_type, 90 unsigned long bl2_base) 91 { 92 unsigned tmp; 93 94 if (load_type == BOT_LOAD) { 95 bl2_mem_layout->total_base = bl2_base; 96 tmp = bl1_mem_layout->free_base - bl2_base; 97 bl2_mem_layout->total_size = bl1_mem_layout->free_size + tmp; 98 99 } else { 100 bl2_mem_layout->total_base = bl1_mem_layout->free_base; 101 tmp = bl1_mem_layout->total_base + bl1_mem_layout->total_size; 102 bl2_mem_layout->total_size = tmp - bl1_mem_layout->free_base; 103 } 104 105 bl2_mem_layout->free_base = bl1_mem_layout->free_base; 106 bl2_mem_layout->free_size = bl1_mem_layout->free_size; 107 bl2_mem_layout->attr = load_type; 108 109 flush_dcache_range((unsigned long) bl2_mem_layout, sizeof(meminfo_t)); 110 return; 111 } 112 113 static void dump_load_info(unsigned long image_load_addr, 114 unsigned long image_size, 115 const meminfo_t *mem_layout) 116 { 117 #if DEBUG 118 printf("Trying to load image at address 0x%lx, size = 0x%lx\r\n", 119 image_load_addr, image_size); 120 printf("Current memory layout:\r\n"); 121 printf(" total region = [0x%lx, 0x%lx]\r\n", mem_layout->total_base, 122 mem_layout->total_base + mem_layout->total_size); 123 printf(" free region = [0x%lx, 0x%lx]\r\n", mem_layout->free_base, 124 mem_layout->free_base + mem_layout->free_size); 125 #endif 126 } 127 128 /* Generic function to return the size of an image */ 129 unsigned long image_size(const char *image_name) 130 { 131 uintptr_t dev_handle; 132 uintptr_t image_handle; 133 uintptr_t image_spec; 134 size_t image_size = 0; 135 int io_result = IO_FAIL; 136 137 assert(image_name != NULL); 138 139 /* Obtain a reference to the image by querying the platform layer */ 140 io_result = plat_get_image_source(image_name, &dev_handle, &image_spec); 141 if (io_result != IO_SUCCESS) { 142 WARN("Failed to obtain reference to image '%s' (%i)\n", 143 image_name, io_result); 144 return 0; 145 } 146 147 /* Attempt to access the image */ 148 io_result = io_open(dev_handle, image_spec, &image_handle); 149 if (io_result != IO_SUCCESS) { 150 WARN("Failed to access image '%s' (%i)\n", 151 image_name, io_result); 152 return 0; 153 } 154 155 /* Find the size of the image */ 156 io_result = io_size(image_handle, &image_size); 157 if ((io_result != IO_SUCCESS) || (image_size == 0)) { 158 WARN("Failed to determine the size of the image '%s' file (%i)\n", 159 image_name, io_result); 160 } 161 io_result = io_close(image_handle); 162 /* Ignore improbable/unrecoverable error in 'close' */ 163 164 /* TODO: Consider maintaining open device connection from this 165 * bootloader stage 166 */ 167 io_result = io_dev_close(dev_handle); 168 /* Ignore improbable/unrecoverable error in 'dev_close' */ 169 170 return image_size; 171 } 172 /******************************************************************************* 173 * Generic function to load an image into the trusted RAM, 174 * given a name, extents of free memory & whether the image should be loaded at 175 * the bottom or top of the free memory. It updates the memory layout if the 176 * load is successful. It also updates the image information and the entry point 177 * information in the params passed 178 ******************************************************************************/ 179 int load_image(meminfo_t *mem_layout, 180 const char *image_name, 181 unsigned int load_type, 182 unsigned long fixed_addr, 183 image_info_t *image_data, 184 entry_point_info_t *entry_point_info) 185 { 186 uintptr_t dev_handle; 187 uintptr_t image_handle; 188 uintptr_t image_spec; 189 unsigned long temp_image_base = 0; 190 unsigned long image_base = 0; 191 long offset = 0; 192 size_t image_size = 0; 193 size_t bytes_read = 0; 194 int io_result = IO_FAIL; 195 196 assert(mem_layout != NULL); 197 assert(image_name != NULL); 198 assert(image_data->h.version >= VERSION_1); 199 200 /* Obtain a reference to the image by querying the platform layer */ 201 io_result = plat_get_image_source(image_name, &dev_handle, &image_spec); 202 if (io_result != IO_SUCCESS) { 203 WARN("Failed to obtain reference to image '%s' (%i)\n", 204 image_name, io_result); 205 return io_result; 206 } 207 208 /* Attempt to access the image */ 209 io_result = io_open(dev_handle, image_spec, &image_handle); 210 if (io_result != IO_SUCCESS) { 211 WARN("Failed to access image '%s' (%i)\n", 212 image_name, io_result); 213 return io_result; 214 } 215 216 /* Find the size of the image */ 217 io_result = io_size(image_handle, &image_size); 218 if ((io_result != IO_SUCCESS) || (image_size == 0)) { 219 WARN("Failed to determine the size of the image '%s' file (%i)\n", 220 image_name, io_result); 221 goto exit; 222 } 223 224 /* See if we have enough space */ 225 if (image_size > mem_layout->free_size) { 226 WARN("Cannot load '%s' file: Not enough space.\n", 227 image_name); 228 dump_load_info(0, image_size, mem_layout); 229 goto exit; 230 } 231 232 switch (load_type) { 233 234 case TOP_LOAD: 235 236 /* Load the image in the top of free memory */ 237 temp_image_base = mem_layout->free_base + mem_layout->free_size; 238 temp_image_base -= image_size; 239 240 /* Page align base address and check whether the image still fits */ 241 image_base = page_align(temp_image_base, DOWN); 242 assert(image_base <= temp_image_base); 243 244 if (image_base < mem_layout->free_base) { 245 WARN("Cannot load '%s' file: Not enough space.\n", 246 image_name); 247 dump_load_info(image_base, image_size, mem_layout); 248 io_result = -ENOMEM; 249 goto exit; 250 } 251 252 /* Calculate the amount of extra memory used due to alignment */ 253 offset = temp_image_base - image_base; 254 255 break; 256 257 case BOT_LOAD: 258 259 /* Load the BL2 image in the bottom of free memory */ 260 temp_image_base = mem_layout->free_base; 261 image_base = page_align(temp_image_base, UP); 262 assert(image_base >= temp_image_base); 263 264 /* Page align base address and check whether the image still fits */ 265 if (image_base + image_size > 266 mem_layout->free_base + mem_layout->free_size) { 267 WARN("Cannot load '%s' file: Not enough space.\n", 268 image_name); 269 dump_load_info(image_base, image_size, mem_layout); 270 io_result = -ENOMEM; 271 goto exit; 272 } 273 274 /* Calculate the amount of extra memory used due to alignment */ 275 offset = image_base - temp_image_base; 276 277 break; 278 279 default: 280 assert(0); 281 282 } 283 284 /* 285 * Some images must be loaded at a fixed address, not a dynamic one. 286 * 287 * This has been implemented as a hack on top of the existing dynamic 288 * loading mechanism, for the time being. If the 'fixed_addr' function 289 * argument is different from zero, then it will force the load address. 290 * So we still have this principle of top/bottom loading but the code 291 * determining the load address is bypassed and the load address is 292 * forced to the fixed one. 293 * 294 * This can result in quite a lot of wasted space because we still use 295 * 1 sole meminfo structure to represent the extents of free memory, 296 * where we should use some sort of linked list. 297 * 298 * E.g. we want to load BL2 at address 0x04020000, the resulting memory 299 * layout should look as follows: 300 * ------------ 0x04040000 301 * | | <- Free space (1) 302 * |----------| 303 * | BL2 | 304 * |----------| 0x04020000 305 * | | <- Free space (2) 306 * |----------| 307 * | BL1 | 308 * ------------ 0x04000000 309 * 310 * But in the current hacky implementation, we'll need to specify 311 * whether BL2 is loaded at the top or bottom of the free memory. 312 * E.g. if BL2 is considered as top-loaded, the meminfo structure 313 * will give the following view of the memory, hiding the chunk of 314 * free memory above BL2: 315 * ------------ 0x04040000 316 * | | 317 * | | 318 * | BL2 | 319 * |----------| 0x04020000 320 * | | <- Free space (2) 321 * |----------| 322 * | BL1 | 323 * ------------ 0x04000000 324 */ 325 if (fixed_addr != 0) { 326 /* Load the image at the given address. */ 327 image_base = fixed_addr; 328 329 /* Check whether the image fits. */ 330 if ((image_base < mem_layout->free_base) || 331 (image_base + image_size > 332 mem_layout->free_base + mem_layout->free_size)) { 333 WARN("Cannot load '%s' file: Not enough space.\n", 334 image_name); 335 dump_load_info(image_base, image_size, mem_layout); 336 io_result = -ENOMEM; 337 goto exit; 338 } 339 340 /* Check whether the fixed load address is page-aligned. */ 341 if (!is_page_aligned(image_base)) { 342 WARN("Cannot load '%s' file at unaligned address 0x%lx\n", 343 image_name, fixed_addr); 344 io_result = -ENOMEM; 345 goto exit; 346 } 347 348 /* 349 * Calculate the amount of extra memory used due to fixed 350 * loading. 351 */ 352 if (load_type == TOP_LOAD) { 353 unsigned long max_addr, space_used; 354 /* 355 * ------------ max_addr 356 * | /wasted/ | | offset 357 * |..........|.............................. 358 * | image | | image_flen 359 * |----------| fixed_addr 360 * | | 361 * | | 362 * ------------ total_base 363 */ 364 max_addr = mem_layout->total_base + mem_layout->total_size; 365 /* 366 * Compute the amount of memory used by the image. 367 * Corresponds to all space above the image load 368 * address. 369 */ 370 space_used = max_addr - fixed_addr; 371 /* 372 * Calculate the amount of wasted memory within the 373 * amount of memory used by the image. 374 */ 375 offset = space_used - image_size; 376 } else /* BOT_LOAD */ 377 /* 378 * ------------ 379 * | | 380 * | | 381 * |----------| 382 * | image | 383 * |..........| fixed_addr 384 * | /wasted/ | | offset 385 * ------------ total_base 386 */ 387 offset = fixed_addr - mem_layout->total_base; 388 } 389 390 /* We have enough space so load the image now */ 391 /* TODO: Consider whether to try to recover/retry a partially successful read */ 392 io_result = io_read(image_handle, image_base, image_size, &bytes_read); 393 if ((io_result != IO_SUCCESS) || (bytes_read < image_size)) { 394 WARN("Failed to load '%s' file (%i)\n", image_name, io_result); 395 goto exit; 396 } 397 398 image_data->image_base = image_base; 399 image_data->image_size = image_size; 400 401 entry_point_info->pc = image_base; 402 403 /* 404 * File has been successfully loaded. Update the free memory 405 * data structure & flush the contents of the TZRAM so that 406 * the next EL can see it. 407 */ 408 /* Update the memory contents */ 409 flush_dcache_range(image_base, image_size); 410 411 mem_layout->free_size -= image_size + offset; 412 413 /* Update the base of free memory since its moved up */ 414 if (load_type == BOT_LOAD) 415 mem_layout->free_base += offset + image_size; 416 417 exit: 418 io_close(image_handle); 419 /* Ignore improbable/unrecoverable error in 'close' */ 420 421 /* TODO: Consider maintaining open device connection from this bootloader stage */ 422 io_dev_close(dev_handle); 423 /* Ignore improbable/unrecoverable error in 'dev_close' */ 424 425 return io_result; 426 } 427