1 /* 2 * Copyright (C) 2017 BlueKitchen GmbH 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of the copyright holders nor the names of 14 * contributors may be used to endorse or promote products derived 15 * from this software without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS 18 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 19 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 20 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL BLUEKITCHEN 21 * GMBH OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 22 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 23 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 24 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 25 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 26 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF 27 * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28 * SUCH DAMAGE. 29 * 30 */ 31 32 #define BTSTACK_FILE__ "btstack_tlv_flash_bank.c" 33 34 #include "btstack_tlv.h" 35 #include "btstack_tlv_flash_bank.h" 36 #include "btstack_debug.h" 37 #include "btstack_util.h" 38 #include "btstack_debug.h" 39 40 #include <string.h> 41 #include <inttypes.h> 42 43 // Header: 44 // - Magic: 'BTstack' 45 // - Status: 46 // - bits 765432: reserved 47 // - bits 10: epoch 48 49 // Entries 50 // - Tag: 32 bit 51 // - Len: 32 bit 52 // - if ENABLE_TLV_FLASH_EXPLICIT_DELETE_FIELD is used 53 // - padding to align delete field 54 // - Delete: 32 bit 55 // - padding to align value field 56 // - Value: Len in bytes 57 58 // Alignment 59 // Tag is aligned to the alignment from hal_flash_bank_t 60 // If ENABLE_TLV_FLASH_EXPLICIT_DELETE_FIELD is used, both Delete and Value are aligned, too 61 62 // ENABLE_TLV_FLASH_EXPLICIT_DELETE_FIELD 63 // 64 // Most Flash implementations allow to: 65 // - erase sector -> all values are 0xff 66 // - write value (1s -> 0s) 67 // - overwrite value with zero (remaining 1s -> 0s) 68 // 69 // We use the ability to overwrite a value with zeros to mark deleted entries (by writing zero into the tag field). 70 // Some targets, E.g. Kinetix K64F, do not allow for that. 71 // 72 // With ENABLE_TLV_FLASH_EXPLICIT_DELETE_FIELD an extra field is reserved to indicate a deleted tag, while keeping main logic 73 // 74 // With ENABLE_TLV_FLASH_WRITE_ONCE, tags are never marked as deleted. Instead, an emtpy tag will be written instead. 75 // Also, lookup and migrate requires to always search until the end of the valid bank 76 77 #if defined (ENABLE_TLV_FLASH_EXPLICIT_DELETE_FIELD) && defined (ENABLE_TLV_FLASH_WRITE_ONCE) 78 #error "Please define either ENABLE_TLV_FLASH_EXPLICIT_DELETE_FIELD or ENABLE_TLV_FLASH_WRITE_ONCE" 79 #endif 80 81 #define BTSTACK_TLV_BANK_HEADER_LEN 8 82 #define BTSTACK_TLV_ENTRY_HEADER_LEN 8 83 84 #ifndef BTSTACK_FLASH_ALIGNMENT_MAX 85 #define BTSTACK_FLASH_ALIGNMENT_MAX 16 86 #endif 87 88 static const char * btstack_tlv_header_magic = "BTstack"; 89 90 // TLV Iterator 91 typedef struct { 92 int bank; 93 uint32_t offset; 94 uint32_t size; 95 uint32_t tag; 96 uint32_t len; 97 } tlv_iterator_t; 98 99 static uint32_t btstack_tlv_flash_bank_align_size(btstack_tlv_flash_bank_t * self, uint32_t size){ 100 uint32_t alignment = self->hal_flash_bank_impl->get_alignment(self->hal_flash_bank_context); 101 return (size + alignment - 1) & ~(alignment - 1); 102 } 103 104 static uint32_t btstack_tlv_flash_bank_aligned_entry_size(btstack_tlv_flash_bank_t * self, uint32_t size) { 105 #ifdef ENABLE_TLV_FLASH_EXPLICIT_DELETE_FIELD 106 // entry header and delete fields are already padded 107 return self->entry_header_len + self->delete_tag_len + btstack_tlv_flash_bank_align_size(self, size); 108 #else 109 // otherwise, data starts right after entry header 110 return btstack_tlv_flash_bank_align_size(self, self->entry_header_len + size); 111 #endif 112 } 113 114 // support unaligned flash read/writes 115 // strategy: increase size to meet alignment, perform unaligned read/write of last chunk with helper buffer 116 117 static void btstack_tlv_flash_bank_read(btstack_tlv_flash_bank_t * self, int bank, uint32_t offset, uint8_t * buffer, uint32_t size){ 118 119 // read main data 120 uint32_t alignment = self->hal_flash_bank_impl->get_alignment(self->hal_flash_bank_context); 121 uint32_t lower_bits = size & (alignment - 1); 122 uint32_t size_aligned = size - lower_bits; 123 if (size_aligned){ 124 self->hal_flash_bank_impl->read(self->hal_flash_bank_context, bank, offset, buffer, size_aligned); 125 buffer += size_aligned; 126 offset += size_aligned; 127 size -= size_aligned; 128 } 129 130 // read last part 131 if (size == 0) return; 132 uint8_t alignment_block[BTSTACK_FLASH_ALIGNMENT_MAX]; 133 self->hal_flash_bank_impl->read(self->hal_flash_bank_context, bank, offset, alignment_block, alignment); 134 memcpy(buffer, alignment_block, size); 135 } 136 137 static void btstack_tlv_flash_bank_write(btstack_tlv_flash_bank_t * self, int bank, uint32_t offset, const uint8_t * buffer, uint32_t size){ 138 139 // write main data 140 uint32_t alignment = self->hal_flash_bank_impl->get_alignment(self->hal_flash_bank_context); 141 uint32_t lower_bits = size & (alignment - 1); 142 uint32_t size_aligned = size - lower_bits; 143 if (size_aligned){ 144 self->hal_flash_bank_impl->write(self->hal_flash_bank_context, bank, offset, buffer, size_aligned); 145 buffer += size_aligned; 146 offset += size_aligned; 147 size -= size_aligned; 148 } 149 150 // write last part 151 if (size == 0) return; 152 uint8_t alignment_block[BTSTACK_FLASH_ALIGNMENT_MAX]; 153 memset(alignment_block, 0xff, alignment); 154 memcpy(alignment_block, buffer, lower_bits); 155 self->hal_flash_bank_impl->write(self->hal_flash_bank_context, bank, offset, alignment_block, alignment); 156 } 157 158 159 // iterator 160 161 static void btstack_tlv_flash_bank_iterator_fetch_tag_len(btstack_tlv_flash_bank_t * self, tlv_iterator_t * it){ 162 // abort if header doesn't fit into remaining space 163 if (it->offset + self->entry_header_len + self->delete_tag_len >= self->hal_flash_bank_impl->get_size(self->hal_flash_bank_context)){ 164 it->tag = 0xffffffff; 165 return; 166 } 167 168 uint8_t entry[BTSTACK_TLV_ENTRY_HEADER_LEN]; 169 btstack_tlv_flash_bank_read(self, it->bank, it->offset, entry, BTSTACK_TLV_ENTRY_HEADER_LEN); 170 it->tag = big_endian_read_32(entry, 0); 171 it->len = big_endian_read_32(entry, 4); 172 173 #ifdef ENABLE_TLV_FLASH_EXPLICIT_DELETE_FIELD 174 // clear tag, if delete field is set 175 uint32_t delete_tag; 176 btstack_tlv_flash_bank_read(self, it->bank, it->offset + self->entry_header_len, (uint8_t *) &delete_tag, 4); 177 if (delete_tag == 0){ 178 it->tag = 0; 179 } 180 #endif 181 } 182 183 static void btstack_tlv_flash_bank_iterator_init(btstack_tlv_flash_bank_t * self, tlv_iterator_t * it, int bank){ 184 memset(it, 0, sizeof(tlv_iterator_t)); 185 it->bank = bank; 186 it->offset = btstack_tlv_flash_bank_align_size(self, BTSTACK_TLV_BANK_HEADER_LEN); 187 it->size = self->hal_flash_bank_impl->get_size(self->hal_flash_bank_context); 188 btstack_tlv_flash_bank_iterator_fetch_tag_len(self, it); 189 } 190 191 static bool btstack_tlv_flash_bank_iterator_has_next(btstack_tlv_flash_bank_t * self, tlv_iterator_t * it){ 192 UNUSED(self); 193 return it->tag != 0xffffffff; 194 } 195 196 static void tlv_iterator_fetch_next(btstack_tlv_flash_bank_t * self, tlv_iterator_t * it){ 197 it->offset += btstack_tlv_flash_bank_aligned_entry_size(self, it->len); 198 199 if (it->offset >= it->size) { 200 it->tag = 0xffffffff; 201 it->len = 0; 202 return; 203 } 204 btstack_tlv_flash_bank_iterator_fetch_tag_len(self, it); 205 } 206 207 // 208 209 // check both banks for headers and pick the one with the higher epoch % 4 210 // @returns bank or -1 if something is invalid 211 static int btstack_tlv_flash_bank_get_latest_bank(btstack_tlv_flash_bank_t * self){ 212 uint8_t header0[BTSTACK_TLV_BANK_HEADER_LEN]; 213 uint8_t header1[BTSTACK_TLV_BANK_HEADER_LEN]; 214 btstack_tlv_flash_bank_read(self, 0, 0, &header0[0], BTSTACK_TLV_BANK_HEADER_LEN); 215 btstack_tlv_flash_bank_read(self, 1, 0, &header1[0], BTSTACK_TLV_BANK_HEADER_LEN); 216 int valid0 = memcmp(header0, btstack_tlv_header_magic, BTSTACK_TLV_BANK_HEADER_LEN-1) == 0; 217 int valid1 = memcmp(header1, btstack_tlv_header_magic, BTSTACK_TLV_BANK_HEADER_LEN-1) == 0; 218 if (!valid0 && !valid1) return -1; 219 if ( valid0 && !valid1) return 0; 220 if (!valid0 && valid1) return 1; 221 int epoch0 = header0[BTSTACK_TLV_BANK_HEADER_LEN-1] & 0x03; 222 int epoch1 = header1[BTSTACK_TLV_BANK_HEADER_LEN-1] & 0x03; 223 if (epoch0 == ((epoch1 + 1) & 0x03)) return 0; 224 if (epoch1 == ((epoch0 + 1) & 0x03)) return 1; 225 return -1; // invalid, must not happen 226 } 227 228 static void btstack_tlv_flash_bank_write_header(btstack_tlv_flash_bank_t * self, int bank, int epoch){ 229 uint8_t header[BTSTACK_TLV_BANK_HEADER_LEN]; 230 memcpy(&header[0], btstack_tlv_header_magic, BTSTACK_TLV_BANK_HEADER_LEN-1); 231 header[BTSTACK_TLV_BANK_HEADER_LEN-1] = epoch; 232 btstack_tlv_flash_bank_write(self, bank, 0, header, BTSTACK_TLV_BANK_HEADER_LEN); 233 } 234 235 /** 236 * @brief Check if erased from offset 237 */ 238 static int btstack_tlv_flash_bank_test_erased(btstack_tlv_flash_bank_t * self, int bank, uint32_t offset){ 239 log_info("test erased: bank %u, offset %u", bank, (unsigned int) offset); 240 uint32_t size = self->hal_flash_bank_impl->get_size(self->hal_flash_bank_context); 241 uint8_t buffer[16]; 242 uint8_t empty16[16]; 243 memset(empty16, 0xff, sizeof(empty16)); 244 while (offset < size){ 245 uint32_t copy_size = (offset + sizeof(empty16) < size) ? sizeof(empty16) : (size - offset); 246 btstack_tlv_flash_bank_read(self, bank, offset, buffer, copy_size); 247 if (memcmp(buffer, empty16, copy_size) != 0) { 248 log_info("not erased %x - %x", (unsigned int) offset, (unsigned int) (offset + copy_size)); 249 return 0; 250 } 251 offset += copy_size; 252 } 253 return 1; 254 } 255 256 /** 257 * @brief erase bank (only if not already erased) 258 */ 259 static void btstack_tlv_flash_bank_erase_bank(btstack_tlv_flash_bank_t * self, int bank){ 260 if (btstack_tlv_flash_bank_test_erased(self, bank, 0)){ 261 log_info("bank %u already erased", bank); 262 } else { 263 log_info("bank %u not empty, erase bank", bank); 264 self->hal_flash_bank_impl->erase(self->hal_flash_bank_context, bank); 265 } 266 } 267 268 static void btstack_tlv_flash_bank_migrate(btstack_tlv_flash_bank_t * self){ 269 270 int next_bank = 1 - self->current_bank; 271 log_info("migrate bank %u -> bank %u", self->current_bank, next_bank); 272 // erase bank (if needed) 273 btstack_tlv_flash_bank_erase_bank(self, next_bank); 274 uint32_t next_write_pos = btstack_tlv_flash_bank_align_size (self, BTSTACK_TLV_BANK_HEADER_LEN);; 275 276 tlv_iterator_t it; 277 btstack_tlv_flash_bank_iterator_init(self, &it, self->current_bank); 278 while (btstack_tlv_flash_bank_iterator_has_next(self, &it)){ 279 // skip deleted entries 280 if (it.tag) { 281 uint32_t tag_len = it.len; 282 uint32_t tag_index = it.offset; 283 284 bool tag_valid = true; 285 286 #ifdef ENABLE_TLV_FLASH_WRITE_ONCE 287 // search until end for newer entry of same tag 288 tlv_iterator_t it2; 289 memcpy(&it2, &it, sizeof(tlv_iterator_t)); 290 while (btstack_tlv_flash_bank_iterator_has_next(self, &it2)){ 291 if ((it2.offset != it.offset) && (it2.tag == it.tag)){ 292 tag_valid = false; 293 break; 294 } 295 tlv_iterator_fetch_next(self, &it2); 296 } 297 if (tag_valid == false){ 298 log_info("skip pos %u, tag '%x' as newer entry found at %u", (unsigned int) tag_index, (unsigned int) it.tag, 299 (unsigned int) it2.offset); 300 } 301 #endif 302 303 if (tag_valid) { 304 305 log_info("migrate pos %u, tag '%x' len %u -> new pos %u", 306 (unsigned int) tag_index, (unsigned int) it.tag, (unsigned int) tag_len, 307 (unsigned int) next_write_pos); 308 309 uint32_t write_offset = next_write_pos; 310 uint32_t bytes_to_copy; 311 uint32_t entry_size = btstack_tlv_flash_bank_aligned_entry_size(self, tag_len); 312 313 #ifdef ENABLE_TLV_FLASH_EXPLICIT_DELETE_FIELD 314 // copy in two steps to skip delete field 315 316 // copy header 317 uint8_t header_buffer[BTSTACK_TLV_ENTRY_HEADER_LEN]; 318 btstack_tlv_flash_bank_read(self, self->current_bank, tag_index, header_buffer, BTSTACK_TLV_ENTRY_HEADER_LEN); 319 btstack_tlv_flash_bank_write(self, next_bank, next_write_pos, header_buffer, BTSTACK_TLV_ENTRY_HEADER_LEN); 320 tag_index += self->entry_header_len + self->delete_tag_len; 321 write_offset += self->entry_header_len + self->delete_tag_len; 322 323 // preparee copy value 324 bytes_to_copy = tag_len; 325 #else 326 // copy everything as one block 327 bytes_to_copy = entry_size; 328 #endif 329 330 // copy value 331 uint8_t copy_buffer[32]; 332 while (bytes_to_copy > 0) { 333 uint32_t bytes_this_iteration = btstack_min(bytes_to_copy, sizeof(copy_buffer)); 334 btstack_tlv_flash_bank_read(self, self->current_bank, tag_index, copy_buffer, bytes_this_iteration); 335 btstack_tlv_flash_bank_write(self, next_bank, write_offset, copy_buffer, bytes_this_iteration); 336 tag_index += bytes_this_iteration; 337 write_offset += bytes_this_iteration; 338 bytes_to_copy -= bytes_this_iteration; 339 } 340 next_write_pos += entry_size; 341 } 342 } 343 tlv_iterator_fetch_next(self, &it); 344 } 345 346 // prepare new one 347 uint8_t epoch_buffer; 348 btstack_tlv_flash_bank_read(self, self->current_bank, BTSTACK_TLV_BANK_HEADER_LEN-1, &epoch_buffer, 1); 349 btstack_tlv_flash_bank_write_header(self, next_bank, (epoch_buffer + 1) & 3); 350 self->current_bank = next_bank; 351 self->write_offset = next_write_pos; 352 } 353 354 #ifndef ENABLE_TLV_FLASH_WRITE_ONCE 355 static void btstack_tlv_flash_bank_delete_tag_until_offset(btstack_tlv_flash_bank_t * self, uint32_t tag, uint32_t offset){ 356 tlv_iterator_t it; 357 btstack_tlv_flash_bank_iterator_init(self, &it, self->current_bank); 358 while (btstack_tlv_flash_bank_iterator_has_next(self, &it) && it.offset < offset){ 359 if (it.tag == tag){ 360 log_info("Erase tag '%x' at position %u", (unsigned int) tag, (unsigned int) it.offset); 361 362 // mark entry as invalid 363 uint32_t zero_value = 0; 364 #ifdef ENABLE_TLV_FLASH_EXPLICIT_DELETE_FIELD 365 // write delete field after entry header 366 btstack_tlv_flash_bank_write(self, self->current_bank, it.offset+self->entry_header_len, (uint8_t*) &zero_value, sizeof(zero_value)); 367 #else 368 uint32_t alignment = self->hal_flash_bank_impl->get_alignment(self->hal_flash_bank_context); 369 if (alignment <= 4){ 370 // if alignment < 4, overwrite only tag with zero value 371 btstack_tlv_flash_bank_write(self, self->current_bank, it.offset, (uint8_t*) &zero_value, sizeof(zero_value)); 372 } else { 373 // otherwise, overwrite complete entry. This results in a sequence of { tag: 0, len: 0 } entries 374 uint8_t zero_buffer[32]; 375 memset(zero_buffer, 0, sizeof(zero_buffer)); 376 uint32_t entry_offset = 0; 377 uint32_t entry_size = btstack_tlv_flash_bank_aligned_entry_size(self, it.len); 378 while (entry_offset < entry_size) { 379 uint32_t bytes_to_write = btstack_min(entry_size - entry_offset, sizeof(zero_buffer)); 380 btstack_tlv_flash_bank_write(self, self->current_bank, it.offset + entry_offset, zero_buffer, bytes_to_write); 381 entry_offset += bytes_to_write; 382 } 383 } 384 #endif 385 } 386 tlv_iterator_fetch_next(self, &it); 387 } 388 } 389 #endif 390 391 /** 392 * Get Value for Tag 393 * @param tag 394 * @param buffer 395 * @param buffer_size 396 * @returns size of value 397 */ 398 static int btstack_tlv_flash_bank_get_tag(void * context, uint32_t tag, uint8_t * buffer, uint32_t buffer_size){ 399 400 btstack_tlv_flash_bank_t * self = (btstack_tlv_flash_bank_t *) context; 401 402 uint32_t tag_index = 0; 403 uint32_t tag_len = 0; 404 tlv_iterator_t it; 405 btstack_tlv_flash_bank_iterator_init(self, &it, self->current_bank); 406 while (btstack_tlv_flash_bank_iterator_has_next(self, &it)){ 407 if (it.tag == tag){ 408 log_info("Found tag '%x' at position %u", (unsigned int) tag, (unsigned int) it.offset); 409 tag_index = it.offset; 410 tag_len = it.len; 411 #ifndef ENABLE_TLV_FLASH_WRITE_ONCE 412 break; 413 #endif 414 } 415 tlv_iterator_fetch_next(self, &it); 416 } 417 if (tag_index == 0) return 0; 418 if (!buffer) return tag_len; 419 int copy_size = btstack_min(buffer_size, tag_len); 420 uint32_t value_offset = tag_index + self->entry_header_len; 421 #ifdef ENABLE_TLV_FLASH_EXPLICIT_DELETE_FIELD 422 // skip delete field 423 value_offset += self->delete_tag_len; 424 #endif 425 btstack_tlv_flash_bank_read(self, self->current_bank, value_offset, buffer, copy_size); 426 return copy_size; 427 } 428 429 /** 430 * Store Tag 431 * @param tag 432 * @param data 433 * @param data_size 434 */ 435 static int btstack_tlv_flash_bank_store_tag(void * context, uint32_t tag, const uint8_t * data, uint32_t data_size){ 436 437 btstack_tlv_flash_bank_t * self = (btstack_tlv_flash_bank_t *) context; 438 439 // trigger migration if not enough space 440 uint32_t required_space = self->entry_header_len + self->delete_tag_len + data_size; 441 if (self->write_offset + required_space > self->hal_flash_bank_impl->get_size(self->hal_flash_bank_context)){ 442 btstack_tlv_flash_bank_migrate(self); 443 } 444 445 if (self->write_offset + required_space > self->hal_flash_bank_impl->get_size(self->hal_flash_bank_context)){ 446 log_error("couldn't write entry, not enough space left"); 447 return 2; 448 } 449 450 // prepare entry 451 log_info("write '%" PRIx32 "', len %" PRIu32 " at %" PRIx32, tag, data_size, self->write_offset); 452 453 uint8_t alignment_buffer[BTSTACK_FLASH_ALIGNMENT_MAX]; 454 memset(alignment_buffer, 0, sizeof(alignment_buffer)); 455 big_endian_store_32(alignment_buffer, 0, tag); 456 big_endian_store_32(alignment_buffer, 4, data_size); 457 458 uint32_t header_len = BTSTACK_TLV_ENTRY_HEADER_LEN; 459 uint32_t value_size = data_size; 460 uint32_t value_offset = self->write_offset + self->entry_header_len; 461 #ifdef ENABLE_TLV_FLASH_EXPLICIT_DELETE_FIELD 462 // skip delete field 463 value_offset += self->delete_tag_len; 464 #else 465 uint32_t alignment = self->hal_flash_bank_impl->get_alignment(self->hal_flash_bank_context); 466 467 // if alignment is larger than the entry header, store parts from value in alignment buffer 468 if (alignment > BTSTACK_TLV_ENTRY_HEADER_LEN){ 469 // calculated number of value bytes to store in alignment buffer 470 uint32_t bytes_from_value = btstack_min(alignment - BTSTACK_TLV_ENTRY_HEADER_LEN, value_size); 471 472 // store parts from value in alignment buffer and update remaining value 473 memcpy(&alignment_buffer[header_len], data, bytes_from_value); 474 header_len += bytes_from_value; 475 data += bytes_from_value; 476 value_size -= bytes_from_value; 477 value_offset = self->write_offset + alignment; 478 } 479 #endif 480 481 // write value first 482 if (value_size > 0){ 483 btstack_tlv_flash_bank_write(self, self->current_bank, value_offset, data, value_size); 484 } 485 486 // then entry 487 btstack_tlv_flash_bank_write(self, self->current_bank, self->write_offset, alignment_buffer, header_len); 488 489 #ifndef ENABLE_TLV_FLASH_WRITE_ONCE 490 // overwrite old entries (if exists) 491 btstack_tlv_flash_bank_delete_tag_until_offset(self, tag, self->write_offset); 492 #endif 493 494 // done 495 self->write_offset += btstack_tlv_flash_bank_aligned_entry_size(self, data_size); 496 497 return 0; 498 } 499 500 /** 501 * Delete Tag 502 * @param tag 503 */ 504 static void btstack_tlv_flash_bank_delete_tag(void * context, uint32_t tag){ 505 #ifdef ENABLE_TLV_FLASH_WRITE_ONCE 506 btstack_tlv_flash_bank_store_tag(context, tag, NULL, 0); 507 #else 508 btstack_tlv_flash_bank_t * self = (btstack_tlv_flash_bank_t *) context; 509 btstack_tlv_flash_bank_delete_tag_until_offset(self, tag, self->write_offset); 510 #endif 511 } 512 513 static const btstack_tlv_t btstack_tlv_flash_bank = { 514 /* int (*get_tag)(..); */ &btstack_tlv_flash_bank_get_tag, 515 /* int (*store_tag)(..); */ &btstack_tlv_flash_bank_store_tag, 516 /* void (*delete_tag)(v..); */ &btstack_tlv_flash_bank_delete_tag, 517 }; 518 519 /** 520 * Init Tag Length Value Store 521 */ 522 const btstack_tlv_t * btstack_tlv_flash_bank_init_instance(btstack_tlv_flash_bank_t * self, const hal_flash_bank_t * hal_flash_bank_impl, void * hal_flash_bank_context){ 523 524 self->hal_flash_bank_impl = hal_flash_bank_impl; 525 self->hal_flash_bank_context = hal_flash_bank_context; 526 self->delete_tag_len = 0; 527 528 // BTSTACK_FLASH_ALIGNMENT_MAX must be larger than alignment 529 uint32_t alignment = self->hal_flash_bank_impl->get_alignment(self->hal_flash_bank_context); 530 btstack_assert(BTSTACK_FLASH_ALIGNMENT_MAX >= alignment); 531 532 #ifdef ENABLE_TLV_FLASH_EXPLICIT_DELETE_FIELD 533 // set delete tag len 534 self->delete_tag_len = (uint8_t) btstack_max(4, alignment); 535 log_info("delete tag len %u", self->delete_tag_len); 536 537 // set aligned entry header len 538 self->entry_header_len = btstack_tlv_flash_bank_align_size(self, BTSTACK_TLV_ENTRY_HEADER_LEN); 539 log_info("entry header len %u", self->entry_header_len); 540 #else 541 UNUSED(alignment); 542 // data starts right after entry header 543 self->entry_header_len = BTSTACK_TLV_ENTRY_HEADER_LEN; 544 #endif 545 546 // try to find current bank 547 self->current_bank = btstack_tlv_flash_bank_get_latest_bank(self); 548 log_info("found bank %d", self->current_bank); 549 if (self->current_bank >= 0){ 550 551 // find last entry and write offset 552 tlv_iterator_t it; 553 #ifndef ENABLE_TLV_FLASH_WRITE_ONCE 554 uint32_t last_tag = 0; 555 uint32_t last_offset = 0; 556 #endif 557 btstack_tlv_flash_bank_iterator_init(self, &it, self->current_bank); 558 while (btstack_tlv_flash_bank_iterator_has_next(self, &it)){ 559 #ifndef ENABLE_TLV_FLASH_WRITE_ONCE 560 last_tag = it.tag; 561 last_offset = it.offset; 562 #endif 563 tlv_iterator_fetch_next(self, &it); 564 } 565 self->write_offset = it.offset; 566 567 if (self->write_offset <= self->hal_flash_bank_impl->get_size(self->hal_flash_bank_context)){ 568 569 #ifndef ENABLE_TLV_FLASH_WRITE_ONCE 570 // delete older instances of last_tag 571 // this handles the unlikely case where MCU did reset after new value + header was written but before delete did complete 572 if (last_tag){ 573 btstack_tlv_flash_bank_delete_tag_until_offset(self, last_tag, last_offset); 574 } 575 #endif 576 577 // verify that rest of bank is empty 578 // this handles the unlikely case where MCU did reset after new value was written, but not the tag 579 if (!btstack_tlv_flash_bank_test_erased(self, self->current_bank, self->write_offset)){ 580 log_info("Flash not empty after last found tag -> migrate"); 581 btstack_tlv_flash_bank_migrate(self); 582 } else { 583 log_info("Flash clean after last found tag"); 584 } 585 } else { 586 // failure! 587 self->current_bank = -1; 588 } 589 } 590 591 if (self->current_bank < 0) { 592 btstack_tlv_flash_bank_erase_bank(self, 0); 593 self->current_bank = 0; 594 btstack_tlv_flash_bank_write_header(self, self->current_bank, 0); // epoch = 0; 595 self->write_offset = btstack_tlv_flash_bank_align_size (self, BTSTACK_TLV_BANK_HEADER_LEN); 596 } 597 598 log_info("write offset %" PRIx32, self->write_offset); 599 return &btstack_tlv_flash_bank; 600 } 601 602