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   1 /***************************************************************************
   2  *   Copyright (C) 2015 by Uwe Bonnes                                      *
   3  *   bon@elektron.ikp.physik.tu-darmstadt.de                               *
   4  *
   5  *   This program is free software; you can redistribute it and/or modify  *
   6  *   it under the terms of the GNU General Public License as published by  *
   7  *   the Free Software Foundation; either version 2 of the License, or     *
   8  *   (at your option) any later version.                                   *
   9  *                                                                         *
  10  *   This program is distributed in the hope that it will be useful,       *
  11  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  12  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  13  *   GNU General Public License for more details.                          *
  14  *                                                                         *
  15  *   You should have received a copy of the GNU General Public License     *
  16  *   along with this program.  If not, see <http://www.gnu.org/licenses/>. *
  17  ***************************************************************************/
  18
  19 #ifdef HAVE_CONFIG_H
  20 #include "config.h"
  21 #endif
  22
  23 #include "imp.h"
  24 #include <helper/binarybuffer.h>
  25 #include <target/algorithm.h>
  26 #include <target/armv7m.h>
  27
  28 /* STM32L4xxx series for reference.
  29  *
  30  * RM0351
  31  * http://www.st.com/st-web-ui/static/active/en/resource/technical/document/reference_manual/DM00083560.pdf
  32  *
  33  * STM32L476RG Datasheet (for erase timing)
  34  * http://www.st.com/st-web-ui/static/active/en/resource/technical/document/datasheet/DM00108832.pdf
  35  *
  36  *
  37  * The device has normally two banks, but on 512 and 256 kiB devices an
  38  * option byte is available to map all sectors to the first bank.
  39  * Both STM32 banks are treated as one OpenOCD bank, as other STM32 devices
  40  * handlers do!
  41  *
  42  */
  43
  44 /* Erase time can be as high as 25ms, 10x this and assume it's toast... */
  45
  46 #define FLASH_ERASE_TIMEOUT 250
  47
  48 #define STM32_FLASH_BASE    0x40022000
  49 #define STM32_FLASH_ACR     0x40022000
  50 #define STM32_FLASH_KEYR    0x40022008
  51 #define STM32_FLASH_OPTKEYR 0x4002200c
  52 #define STM32_FLASH_SR      0x40022010
  53 #define STM32_FLASH_CR      0x40022014
  54 #define STM32_FLASH_OPTR    0x40022020
  55 #define STM32_FLASH_WRP1AR  0x4002202c
  56 #define STM32_FLASH_WRP2AR  0x40022030
  57 #define STM32_FLASH_WRP1BR  0x4002204c
  58 #define STM32_FLASH_WRP2BR  0x40022050
  59
  60 /* FLASH_CR register bits */
  61
  62 #define FLASH_PG       (1 << 0)
  63 #define FLASH_PER      (1 << 1)
  64 #define FLASH_MER1     (1 << 2)
  65 #define FLASH_PAGE_SHIFT     3
  66 #define FLASH_CR_BKER  (1 << 11)
  67 #define FLASH_MER2     (1 << 15)
  68 #define FLASH_STRT     (1 << 16)
  69 #define FLASH_EOPIE    (1 << 24)
  70 #define FLASH_ERRIE    (1 << 25)
  71 #define FLASH_OPTLOCK  (1 << 30)
  72 #define FLASH_LOCK     (1 << 31)
  73
  74 /* FLASH_SR register bits */
  75
  76 #define FLASH_BSY      (1 << 16)
  77 /* Fast programming not used => related errors not used*/
  78 #define FLASH_PGSERR   (1 << 7) /* Programming sequence error */
  79 #define FLASH_SIZERR   (1 << 6) /* Size  error */
  80 #define FLASH_PGAERR   (1 << 5) /* Programming alignment error */
  81 #define FLASH_WRPERR   (1 << 4) /* Write protection error */
  82 #define FLASH_PROGERR  (1 << 3) /* Programming error */
  83 #define FLASH_OPERR    (1 << 1) /* Operation error */
  84 #define FLASH_EOP      (1 << 0) /* End of operation */
  85
  86 #define FLASH_ERROR (FLASH_PGSERR | FLASH_PGSERR | FLASH_PGAERR | FLASH_WRPERR | FLASH_OPERR)
  87
  88 /* STM32_FLASH_OBR bit definitions (reading) */
  89
  90 #define OPT_DUALBANK   21       /* dual flash bank only */
  91
  92 /* register unlock keys */
  93
  94 #define KEY1           0x45670123
  95 #define KEY2           0xCDEF89AB
  96
  97 /* option register unlock key */
  98 #define OPTKEY1        0x08192A3B
  99 #define OPTKEY2        0x4C5D6E7F
 100
 101
 102 /* other registers */
 103 #define DBGMCU_IDCODE   0xE0042000
 104 #define FLASH_SIZE_REG  0x1FFF75E0
 105
 106 struct stm32l4_options {
 107         uint8_t RDP;
 108         uint16_t bank_b_start;
 109         uint8_t user_options;
 110         uint8_t wpr1a_start;
 111         uint8_t wpr1a_end;
 112         uint8_t wpr1b_start;
 113         uint8_t wpr1b_end;
 114         uint8_t wpr2a_start;
 115         uint8_t wpr2a_end;
 116         uint8_t wpr2b_start;
 117         uint8_t wpr2b_end;
 118     /* Fixme: Handle PCROP */
 119 };
 120
 121 struct stm32l4_flash_bank {
 122         struct stm32l4_options option_bytes;
 123         int probed;
 124 };
 125
 126 /* flash bank stm32l4x <base> <size> 0 0 <target#>
 127  */
 128 FLASH_BANK_COMMAND_HANDLER(stm32l4_flash_bank_command)
 129 {
 130         struct stm32l4_flash_bank *stm32l4_info;
 131
 132         if (CMD_ARGC < 6)
 133                 return ERROR_COMMAND_SYNTAX_ERROR;
 134
 135         stm32l4_info = malloc(sizeof(struct stm32l4_flash_bank));
 136         if (!stm32l4_info)
 137                 return ERROR_FAIL; /* Checkme: What better error to use?*/
 138         bank->driver_priv = stm32l4_info;
 139
 140         stm32l4_info->probed = 0;
 141
 142         return ERROR_OK;
 143 }
 144
 145 static inline int stm32l4_get_flash_reg(struct flash_bank *bank, uint32_t reg)
 146 {
 147         return reg;
 148 }
 149
 150 static inline int stm32l4_get_flash_status(struct flash_bank *bank, uint32_t *status)
 151 {
 152         struct target *target = bank->target;
 153         return target_read_u32(
 154                 target, stm32l4_get_flash_reg(bank, STM32_FLASH_SR), status);
 155 }
 156
 157 static int stm32l4_wait_status_busy(struct flash_bank *bank, int timeout)
 158 {
 159         struct target *target = bank->target;
 160         uint32_t status;
 161         int retval = ERROR_OK;
 162
 163         /* wait for busy to clear */
 164         for (;;) {
 165                 retval = stm32l4_get_flash_status(bank, &status);
 166                 if (retval != ERROR_OK)
 167                         return retval;
 168                 LOG_DEBUG("status: 0x%" PRIx32 "", status);
 169                 if ((status & FLASH_BSY) == 0)
 170                         break;
 171                 if (timeout-- <= 0) {
 172                         LOG_ERROR("timed out waiting for flash");
 173                         return ERROR_FAIL;
 174                 }
 175                 alive_sleep(1);
 176         }
 177
 178
 179         if (status & FLASH_WRPERR) {
 180                 LOG_ERROR("stm32x device protected");
 181                 retval = ERROR_FAIL;
 182         }
 183
 184         /* Clear but report errors */
 185         if (status & FLASH_ERROR) {
 186                 /* If this operation fails, we ignore it and report the original
 187                  * retval
 188                  */
 189                 target_write_u32(target, stm32l4_get_flash_reg(bank, STM32_FLASH_SR),
 190                                 status & FLASH_ERROR);
 191         }
 192         return retval;
 193 }
 194
 195 static int stm32l4_unlock_reg(struct target *target)
 196 {
 197         uint32_t ctrl;
 198
 199         /* first check if not already unlocked
 200          * otherwise writing on STM32_FLASH_KEYR will fail
 201          */
 202         int retval = target_read_u32(target, STM32_FLASH_CR, &ctrl);
 203         if (retval != ERROR_OK)
 204                 return retval;
 205
 206         if ((ctrl & FLASH_LOCK) == 0)
 207                 return ERROR_OK;
 208
 209         /* unlock flash registers */
 210         retval = target_write_u32(target, STM32_FLASH_KEYR, KEY1);
 211         if (retval != ERROR_OK)
 212                 return retval;
 213
 214         retval = target_write_u32(target, STM32_FLASH_KEYR, KEY2);
 215         if (retval != ERROR_OK)
 216                 return retval;
 217
 218         retval = target_read_u32(target, STM32_FLASH_CR, &ctrl);
 219         if (retval != ERROR_OK)
 220                 return retval;
 221
 222         if (ctrl & FLASH_LOCK) {
 223                 LOG_ERROR("flash not unlocked STM32_FLASH_CR: %" PRIx32, ctrl);
 224                 return ERROR_TARGET_FAILURE;
 225         }
 226
 227         return ERROR_OK;
 228 }
 229
 230 static int stm32l4_unlock_option_reg(struct target *target)
 231 {
 232         uint32_t ctrl;
 233
 234         int retval = target_read_u32(target, STM32_FLASH_CR, &ctrl);
 235         if (retval != ERROR_OK)
 236                 return retval;
 237
 238         if ((ctrl & FLASH_OPTLOCK) == 0)
 239                 return ERROR_OK;
 240
 241         /* unlock option registers */
 242         retval = target_write_u32(target, STM32_FLASH_OPTKEYR, OPTKEY1);
 243         if (retval != ERROR_OK)
 244                 return retval;
 245
 246         retval = target_write_u32(target, STM32_FLASH_OPTKEYR, OPTKEY2);
 247         if (retval != ERROR_OK)
 248                 return retval;
 249
 250         retval = target_read_u32(target, STM32_FLASH_CR, &ctrl);
 251         if (retval != ERROR_OK)
 252                 return retval;
 253
 254         if (ctrl & FLASH_OPTLOCK) {
 255                 LOG_ERROR("options not unlocked STM32_FLASH_CR: %" PRIx32, ctrl);
 256                 return ERROR_TARGET_FAILURE;
 257         }
 258
 259         return ERROR_OK;
 260 }
 261
 262 static int stm32l4_read_options(struct flash_bank *bank)
 263 {
 264         uint32_t optiondata;
 265         struct stm32l4_flash_bank *stm32l4_info = NULL;
 266         struct target *target = bank->target;
 267
 268         stm32l4_info = bank->driver_priv;
 269
 270         /* read current option bytes */
 271         int retval = target_read_u32(target, STM32_FLASH_OPTR, &optiondata);
 272         if (retval != ERROR_OK)
 273                 return retval;
 274
 275         stm32l4_info->option_bytes.user_options = (optiondata >> 8) & 0x3ffff;
 276         stm32l4_info->option_bytes.RDP = optiondata & 0xff;
 277
 278         retval = target_read_u32(target, STM32_FLASH_WRP1AR, &optiondata);
 279         if (retval != ERROR_OK)
 280                 return retval;
 281         stm32l4_info->option_bytes.wpr1a_start =  optiondata         & 0xff;
 282         stm32l4_info->option_bytes.wpr1a_end   = (optiondata >> 16)  & 0xff;
 283
 284         retval = target_read_u32(target, STM32_FLASH_WRP2AR, &optiondata);
 285         if (retval != ERROR_OK)
 286                 return retval;
 287         stm32l4_info->option_bytes.wpr2a_start =  optiondata         & 0xff;
 288         stm32l4_info->option_bytes.wpr2a_end   = (optiondata >> 16)  & 0xff;
 289
 290         retval = target_read_u32(target, STM32_FLASH_WRP1BR, &optiondata);
 291         if (retval != ERROR_OK)
 292                 return retval;
 293         stm32l4_info->option_bytes.wpr1b_start =  optiondata         & 0xff;
 294         stm32l4_info->option_bytes.wpr1b_end   = (optiondata >> 16)  & 0xff;
 295
 296         retval = target_read_u32(target, STM32_FLASH_WRP2BR, &optiondata);
 297         if (retval != ERROR_OK)
 298                 return retval;
 299         stm32l4_info->option_bytes.wpr2b_start =  optiondata         & 0xff;
 300         stm32l4_info->option_bytes.wpr2b_end   = (optiondata >> 16)  & 0xff;
 301
 302         if (stm32l4_info->option_bytes.RDP != 0xAA)
 303                 LOG_INFO("Device Security Bit Set");
 304
 305         return ERROR_OK;
 306 }
 307
 308 static int stm32l4_write_options(struct flash_bank *bank)
 309 {
 310         struct stm32l4_flash_bank *stm32l4_info = NULL;
 311         struct target *target = bank->target;
 312         uint32_t optiondata;
 313
 314         stm32l4_info = bank->driver_priv;
 315
 316         (void) optiondata;
 317         (void) stm32l4_info;
 318
 319         int retval = stm32l4_unlock_option_reg(target);
 320         if (retval != ERROR_OK)
 321                 return retval;
 322         /* FIXME: Implement Option writing!*/
 323         return ERROR_OK;
 324 }
 325
 326 static int stm32l4_protect_check(struct flash_bank *bank)
 327 {
 328         struct stm32l4_flash_bank *stm32l4_info = bank->driver_priv;
 329
 330         /* read write protection settings */
 331         int retval = stm32l4_read_options(bank);
 332         if (retval != ERROR_OK) {
 333                 LOG_DEBUG("unable to read option bytes");
 334                 return retval;
 335         }
 336
 337         for (int i = 0; i < bank->num_sectors; i++) {
 338                 if (i < stm32l4_info->option_bytes.bank_b_start) {
 339                         if (((i >= stm32l4_info->option_bytes.wpr1a_start) &&
 340                                  (i <= stm32l4_info->option_bytes.wpr1a_end)) ||
 341                                 ((i >= stm32l4_info->option_bytes.wpr2a_start) &&
 342                                  (i <= stm32l4_info->option_bytes.wpr2a_end)))
 343                                 bank->sectors[i].is_protected = 1;
 344                         else
 345                                 bank->sectors[i].is_protected = 0;
 346                 } else {
 347                         uint8_t snb;
 348                         snb = i - stm32l4_info->option_bytes.bank_b_start + 256;
 349                         if (((snb >= stm32l4_info->option_bytes.wpr1b_start) &&
 350                                  (snb <= stm32l4_info->option_bytes.wpr1b_end)) ||
 351                                 ((snb >= stm32l4_info->option_bytes.wpr2b_start) &&
 352                                  (snb <= stm32l4_info->option_bytes.wpr2b_end)))
 353                                 bank->sectors[i].is_protected = 1;
 354                         else
 355                                 bank->sectors[i].is_protected = 0;
 356                 }
 357         }
 358         return ERROR_OK;
 359 }
 360
 361 static int stm32l4_erase(struct flash_bank *bank, int first, int last)
 362 {
 363         struct target *target = bank->target;
 364         int i;
 365
 366         assert(first < bank->num_sectors);
 367         assert(last < bank->num_sectors);
 368
 369         if (bank->target->state != TARGET_HALTED) {
 370                 LOG_ERROR("Target not halted");
 371                 return ERROR_TARGET_NOT_HALTED;
 372         }
 373
 374         int retval;
 375         retval = stm32l4_unlock_reg(target);
 376         if (retval != ERROR_OK)
 377                 return retval;
 378
 379         /*
 380         Sector Erase
 381         To erase a sector, follow the procedure below:
 382         1. Check that no Flash memory operation is ongoing by
 383        checking the BSY bit in the FLASH_SR register
 384         2. Set the PER bit and select the page and bank
 385            you wish to erase  in the FLASH_CR register
 386         3. Set the STRT bit in the FLASH_CR register
 387         4. Wait for the BSY bit to be cleared
 388          */
 389         struct stm32l4_flash_bank *stm32l4_info = bank->driver_priv;
 390
 391         for (i = first; i <= last; i++) {
 392                 uint32_t erase_flags;
 393                 erase_flags = FLASH_PER | FLASH_STRT;
 394
 395                 if  (i >= stm32l4_info->option_bytes.bank_b_start) {
 396                         uint8_t snb;
 397                         snb = (i - stm32l4_info->option_bytes.bank_b_start) + 256;
 398                         erase_flags |= snb << FLASH_PAGE_SHIFT | FLASH_CR_BKER;
 399                 } else
 400                         erase_flags |= i << FLASH_PAGE_SHIFT;
 401                 retval = target_write_u32(target,
 402                                 stm32l4_get_flash_reg(bank, STM32_FLASH_CR), erase_flags);
 403                 if (retval != ERROR_OK)
 404                         return retval;
 405
 406                 retval = stm32l4_wait_status_busy(bank, FLASH_ERASE_TIMEOUT);
 407                 if (retval != ERROR_OK)
 408                         return retval;
 409
 410                 bank->sectors[i].is_erased = 1;
 411         }
 412
 413         retval = target_write_u32(
 414                 target, stm32l4_get_flash_reg(bank, STM32_FLASH_CR), FLASH_LOCK);
 415         if (retval != ERROR_OK)
 416                 return retval;
 417
 418         return ERROR_OK;
 419 }
 420
 421 static int stm32l4_protect(struct flash_bank *bank, int set, int first, int last)
 422 {
 423         struct target *target = bank->target;
 424         struct stm32l4_flash_bank *stm32l4_info = bank->driver_priv;
 425
 426         if (target->state != TARGET_HALTED) {
 427                 LOG_ERROR("Target not halted");
 428                 return ERROR_TARGET_NOT_HALTED;
 429         }
 430
 431         /* read protection settings */
 432         int retval = stm32l4_read_options(bank);
 433         if (retval != ERROR_OK) {
 434                 LOG_DEBUG("unable to read option bytes");
 435                 return retval;
 436         }
 437
 438         (void)stm32l4_info;
 439         /* FIXME: Write First and last in a valid WRPxx_start/end combo*/
 440         retval = stm32l4_write_options(bank);
 441         if (retval != ERROR_OK)
 442                 return retval;
 443
 444         return ERROR_OK;
 445 }
 446
 447 /* Count is in halfwords */
 448 static int stm32l4_write_block(struct flash_bank *bank, const uint8_t *buffer,
 449                 uint32_t offset, uint32_t count)
 450 {
 451         struct target *target = bank->target;
 452         uint32_t buffer_size = 16384;
 453         struct working_area *write_algorithm;
 454         struct working_area *source;
 455         uint32_t address = bank->base + offset;
 456         struct reg_param reg_params[5];
 457         struct armv7m_algorithm armv7m_info;
 458         int retval = ERROR_OK;
 459
 460         /* See contrib/loaders/flash/stm32l4x.S for source and
 461          * hints how to generate the data!
 462          */
 463
 464         static const uint8_t stm32l4_flash_write_code[] = {
 465                 0xd0, 0xf8, 0x00, 0x80, 0xb8, 0xf1, 0x00, 0x0f, 0x21, 0xd0, 0x45, 0x68,
 466                 0xb8, 0xeb, 0x05, 0x06, 0x44, 0xbf, 0x76, 0x18, 0x36, 0x1a, 0x08, 0x2e,
 467                 0xf2, 0xd3, 0xdf, 0xf8, 0x36, 0x60, 0x66, 0x61, 0xf5, 0xe8, 0x02, 0x67,
 468                 0xe2, 0xe8, 0x02, 0x67, 0xbf, 0xf3, 0x4f, 0x8f, 0x26, 0x69, 0x16, 0xf4,
 469                 0x80, 0x3f, 0xfb, 0xd1, 0x16, 0xf0, 0xfa, 0x0f, 0x07, 0xd1, 0x8d, 0x42,
 470                 0x28, 0xbf, 0x00, 0xf1, 0x08, 0x05, 0x45, 0x60, 0x01, 0x3b, 0x13, 0xb1,
 471                 0xda, 0xe7, 0x00, 0x21, 0x41, 0x60, 0x30, 0x46, 0x00, 0xbe, 0x01, 0x00,
 472                 0x00, 0x00
 473         };
 474
 475         if (target_alloc_working_area(target, sizeof(stm32l4_flash_write_code),
 476                         &write_algorithm) != ERROR_OK) {
 477                 LOG_WARNING("no working area available, can't do block memory writes");
 478                 return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
 479         }
 480
 481         retval = target_write_buffer(target, write_algorithm->address,
 482                         sizeof(stm32l4_flash_write_code),
 483                         stm32l4_flash_write_code);
 484         if (retval != ERROR_OK)
 485                 return retval;
 486
 487         /* memory buffer */
 488         while (target_alloc_working_area_try(target, buffer_size, &source) !=
 489                    ERROR_OK) {
 490                 buffer_size /= 2;
 491                 if (buffer_size <= 256) {
 492                         /* we already allocated the writing code, but failed to get a
 493                          * buffer, free the algorithm */
 494                         target_free_working_area(target, write_algorithm);
 495
 496                         LOG_WARNING("no large enough working area available, can't do block memory writes");
 497                         return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
 498                 }
 499         }
 500
 501         armv7m_info.common_magic = ARMV7M_COMMON_MAGIC;
 502         armv7m_info.core_mode = ARM_MODE_THREAD;
 503
 504         init_reg_param(&reg_params[0], "r0", 32, PARAM_IN_OUT); /* buffer start, status (out) */
 505         init_reg_param(&reg_params[1], "r1", 32, PARAM_OUT);    /* buffer end */
 506         init_reg_param(&reg_params[2], "r2", 32, PARAM_OUT);    /* target address */
 507         init_reg_param(&reg_params[3], "r3", 32, PARAM_OUT);    /* count (double word-64bit) */
 508         init_reg_param(&reg_params[4], "r4", 32, PARAM_OUT);    /* flash base */
 509
 510         buf_set_u32(reg_params[0].value, 0, 32, source->address);
 511         buf_set_u32(reg_params[1].value, 0, 32, source->address + source->size);
 512         buf_set_u32(reg_params[2].value, 0, 32, address);
 513         buf_set_u32(reg_params[3].value, 0, 32, count / 4);
 514         buf_set_u32(reg_params[4].value, 0, 32, STM32_FLASH_BASE);
 515
 516         retval = target_run_flash_async_algorithm(target, buffer, count, 2,
 517                         0, NULL,
 518                         5, reg_params,
 519                         source->address, source->size,
 520                         write_algorithm->address, 0,
 521                         &armv7m_info);
 522
 523         if (retval == ERROR_FLASH_OPERATION_FAILED) {
 524                 LOG_ERROR("error executing stm32l4 flash write algorithm");
 525
 526                 uint32_t error = buf_get_u32(reg_params[0].value, 0, 32) & FLASH_ERROR;
 527
 528                 if (error & FLASH_WRPERR)
 529                         LOG_ERROR("flash memory write protected");
 530
 531                 if (error != 0) {
 532                         LOG_ERROR("flash write failed = %08" PRIx32, error);
 533                         /* Clear but report errors */
 534                         target_write_u32(target, STM32_FLASH_SR, error);
 535                         retval = ERROR_FAIL;
 536                 }
 537         }
 538
 539         target_free_working_area(target, source);
 540         target_free_working_area(target, write_algorithm);
 541
 542         destroy_reg_param(&reg_params[0]);
 543         destroy_reg_param(&reg_params[1]);
 544         destroy_reg_param(&reg_params[2]);
 545         destroy_reg_param(&reg_params[3]);
 546         destroy_reg_param(&reg_params[4]);
 547
 548         return retval;
 549 }
 550
 551 static int stm32l4_write(struct flash_bank *bank, const uint8_t *buffer,
 552                 uint32_t offset, uint32_t count)
 553 {
 554         struct target *target = bank->target;
 555         int retval;
 556
 557         if (bank->target->state != TARGET_HALTED) {
 558                 LOG_ERROR("Target not halted");
 559                 return ERROR_TARGET_NOT_HALTED;
 560         }
 561
 562         if (offset & 0x7) {
 563                 LOG_WARNING("offset 0x%" PRIx32 " breaks required 8-byte alignment",
 564                                         offset);
 565                 return ERROR_FLASH_DST_BREAKS_ALIGNMENT;
 566         }
 567
 568         if (count & 0x7) {
 569                 LOG_WARNING("Padding %d bytes to keep 8-byte write size",
 570                                         count & 7);
 571                 count = (count + 7) & ~7;
 572                 /* This pads the write chunk with random bytes by overrunning the
 573                  * write buffer. Padding with the erased pattern 0xff is purely
 574                  * cosmetical, as 8-byte flash words are ECC secured and the first
 575                  * write will program the ECC bits. A second write would need
 576                  * to reprogramm these ECC bits.
 577                  * But this can only be done after erase!
 578                  */
 579         }
 580
 581         retval = stm32l4_unlock_reg(target);
 582         if (retval != ERROR_OK)
 583                 return retval;
 584
 585         /* Only full double words (8-byte) can be programmed*/
 586         retval = stm32l4_write_block(bank, buffer, offset, count / 2);
 587         if (retval != ERROR_OK) {
 588                 LOG_WARNING("block write failed");
 589                 return retval;
 590                 }
 591
 592         LOG_WARNING("block write succeeded");
 593         return target_write_u32(target, STM32_FLASH_CR, FLASH_LOCK);
 594 }
 595
 596 static int stm32l4_probe(struct flash_bank *bank)
 597 {
 598         struct target *target = bank->target;
 599         struct stm32l4_flash_bank *stm32l4_info = bank->driver_priv;
 600         int i;
 601         uint16_t flash_size_in_kb = 0xffff;
 602         uint16_t max_flash_size_in_kb;
 603         uint32_t device_id;
 604         uint32_t options;
 605         uint32_t base_address = 0x08000000;
 606
 607         stm32l4_info->probed = 0;
 608
 609         /* read stm32 device id register */
 610         int retval = target_read_u32(target, DBGMCU_IDCODE, &device_id);
 611         if (retval != ERROR_OK)
 612                 return retval;
 613         LOG_INFO("device id = 0x%08" PRIx32 "", device_id);
 614
 615         /* set max flash size depending on family */
 616         switch (device_id & 0xfff) {
 617         case 0x415:
 618                 max_flash_size_in_kb = 1024;
 619                 break;
 620         default:
 621                 LOG_WARNING("Cannot identify target as a STM32L4 family.");
 622                 return ERROR_FAIL;
 623         }
 624
 625         /* get flash size from target. */
 626         retval = target_read_u16(target, FLASH_SIZE_REG, &flash_size_in_kb);
 627
 628         /* failed reading flash size or flash size invalid (early silicon),
 629          * default to max target family */
 630         if (retval != ERROR_OK || flash_size_in_kb == 0xffff || flash_size_in_kb == 0) {
 631                 LOG_WARNING("STM32 flash size failed, probe inaccurate - assuming %dk flash",
 632                         max_flash_size_in_kb);
 633                 flash_size_in_kb = max_flash_size_in_kb;
 634         }
 635
 636         LOG_INFO("flash size = %dkbytes", flash_size_in_kb);
 637
 638         /* did we assign flash size? */
 639         assert(flash_size_in_kb != 0xffff);
 640
 641         /* get options to for DUAL BANK. */
 642         retval = target_read_u32(target, STM32_FLASH_OPTR, &options);
 643
 644         /* only devices with < 1024 kiB may be set to single bank dual banks */
 645         if ((flash_size_in_kb == 1024) || !(options & OPT_DUALBANK))
 646                 stm32l4_info->option_bytes.bank_b_start = 256;
 647         else
 648                 stm32l4_info->option_bytes.bank_b_start = flash_size_in_kb << 9;
 649
 650         /* did we assign flash size? */
 651         assert((flash_size_in_kb != 0xffff) && flash_size_in_kb);
 652
 653         /* calculate numbers of pages */
 654         int num_pages = flash_size_in_kb / 2;
 655
 656         /* check that calculation result makes sense */
 657         assert(num_pages > 0);
 658
 659         if (bank->sectors) {
 660                 free(bank->sectors);
 661                 bank->sectors = NULL;
 662         }
 663
 664         bank->base = base_address;
 665         bank->size = num_pages * (1 << 11);
 666         bank->num_sectors = num_pages;
 667         bank->sectors = malloc(sizeof(struct flash_sector) * num_pages);
 668         if (!bank->sectors)
 669                 return ERROR_FAIL; /* Checkme: What better error to use?*/
 670
 671         for (i = 0; i < num_pages; i++) {
 672                 bank->sectors[i].offset = i << 11;
 673                 bank->sectors[i].size = 1 << 11;
 674                 bank->sectors[i].is_erased = -1;
 675                 bank->sectors[i].is_protected = 1;
 676         }
 677
 678         stm32l4_info->probed = 1;
 679
 680         return ERROR_OK;
 681 }
 682
 683 static int stm32l4_auto_probe(struct flash_bank *bank)
 684 {
 685         struct stm32l4_flash_bank *stm32l4_info = bank->driver_priv;
 686         if (stm32l4_info->probed)
 687                 return ERROR_OK;
 688         return stm32l4_probe(bank);
 689 }
 690
 691 static int get_stm32l4_info(struct flash_bank *bank, char *buf, int buf_size)
 692 {
 693         struct target *target = bank->target;
 694         uint32_t dbgmcu_idcode;
 695
 696         /* read stm32 device id register */
 697         int retval = target_read_u32(target, DBGMCU_IDCODE, &dbgmcu_idcode);
 698         if (retval != ERROR_OK)
 699                 return retval;
 700
 701         uint16_t device_id = dbgmcu_idcode & 0xffff;
 702         uint8_t rev_id = dbgmcu_idcode >> 28;
 703         uint8_t rev_minor = 0;
 704         int i;
 705
 706         for (i = 16; i < 28; i++) {
 707                 if (dbgmcu_idcode & (1 << i))
 708                         rev_minor++;
 709                 else
 710                         break;
 711         }
 712
 713         const char *device_str;
 714
 715         switch (device_id) {
 716         case 0x6415:
 717                 device_str = "STM32L4xx";
 718                 break;
 719
 720         default:
 721                 snprintf(buf, buf_size, "Cannot identify target as a STM32L4\n");
 722                 return ERROR_FAIL;
 723         }
 724
 725         snprintf(buf, buf_size, "%s - Rev: %1d.%02d",
 726                          device_str, rev_id, rev_minor);
 727
 728         return ERROR_OK;
 729 }
 730
 731 COMMAND_HANDLER(stm32l4_handle_lock_command)
 732 {
 733         struct target *target = NULL;
 734         struct stm32l4_flash_bank *stm32l4_info = NULL;
 735
 736         if (CMD_ARGC < 1)
 737                 return ERROR_COMMAND_SYNTAX_ERROR;
 738
 739         struct flash_bank *bank;
 740         int retval = CALL_COMMAND_HANDLER(flash_command_get_bank, 0, &bank);
 741         if (ERROR_OK != retval)
 742                 return retval;
 743
 744         stm32l4_info = bank->driver_priv;
 745         target = bank->target;
 746
 747         if (target->state != TARGET_HALTED) {
 748                 LOG_ERROR("Target not halted");
 749                 return ERROR_TARGET_NOT_HALTED;
 750         }
 751
 752         if (stm32l4_read_options(bank) != ERROR_OK) {
 753                 command_print(CMD_CTX, "%s failed to read options",
 754                                           bank->driver->name);
 755                 return ERROR_OK;
 756         }
 757
 758         /* set readout protection */
 759         stm32l4_info->option_bytes.RDP = 0;
 760
 761         if (stm32l4_write_options(bank) != ERROR_OK) {
 762                 command_print(CMD_CTX, "%s failed to lock device", bank->driver->name);
 763                 return ERROR_OK;
 764         }
 765
 766         command_print(CMD_CTX, "%s locked", bank->driver->name);
 767
 768         return ERROR_OK;
 769 }
 770
 771 COMMAND_HANDLER(stm32l4_handle_unlock_command)
 772 {
 773         struct target *target = NULL;
 774         struct stm32l4_flash_bank *stm32l4_info = NULL;
 775
 776         if (CMD_ARGC < 1)
 777                 return ERROR_COMMAND_SYNTAX_ERROR;
 778
 779         struct flash_bank *bank;
 780         int retval = CALL_COMMAND_HANDLER(flash_command_get_bank, 0, &bank);
 781         if (ERROR_OK != retval)
 782                 return retval;
 783
 784         stm32l4_info = bank->driver_priv;
 785         target = bank->target;
 786
 787         if (target->state != TARGET_HALTED) {
 788                 LOG_ERROR("Target not halted");
 789                 return ERROR_TARGET_NOT_HALTED;
 790         }
 791
 792         if (stm32l4_read_options(bank) != ERROR_OK) {
 793                 command_print(CMD_CTX, "%s failed to read options", bank->driver->name);
 794                 return ERROR_OK;
 795         }
 796
 797         /* clear readout protection and complementary option bytes
 798          * this will also force a device unlock if set */
 799         stm32l4_info->option_bytes.RDP = 0xAA;
 800
 801         if (stm32l4_write_options(bank) != ERROR_OK) {
 802                 command_print(CMD_CTX, "%s failed to unlock device",
 803                                           bank->driver->name);
 804                 return ERROR_OK;
 805         }
 806
 807         command_print(CMD_CTX, "%s unlocked.\n"
 808                         "INFO: a reset or power cycle is required "
 809                         "for the new settings to take effect.", bank->driver->name);
 810
 811         return ERROR_OK;
 812 }
 813
 814 static int stm32l4_mass_erase(struct flash_bank *bank, uint32_t action)
 815 {
 816         int retval;
 817         struct target *target = bank->target;
 818
 819         if (target->state != TARGET_HALTED) {
 820                 LOG_ERROR("Target not halted");
 821                 return ERROR_TARGET_NOT_HALTED;
 822         }
 823
 824         retval = stm32l4_unlock_reg(target);
 825         if (retval != ERROR_OK)
 826                 return retval;
 827
 828         /* mass erase flash memory */
 829         retval = target_write_u32(
 830                 target, stm32l4_get_flash_reg(bank, STM32_FLASH_CR), action);
 831         if (retval != ERROR_OK)
 832                 return retval;
 833         retval = target_write_u32(
 834                 target, stm32l4_get_flash_reg(bank, STM32_FLASH_CR),
 835                 action | FLASH_STRT);
 836         if (retval != ERROR_OK)
 837                 return retval;
 838
 839         retval = stm32l4_wait_status_busy(bank,  FLASH_ERASE_TIMEOUT);
 840         if (retval != ERROR_OK)
 841                 return retval;
 842
 843         retval = target_write_u32(
 844                 target, stm32l4_get_flash_reg(bank, STM32_FLASH_CR), FLASH_LOCK);
 845         if (retval != ERROR_OK)
 846                 return retval;
 847
 848         return ERROR_OK;
 849 }
 850
 851 COMMAND_HANDLER(stm32l4_handle_mass_erase_command)
 852 {
 853         int i;
 854         uint32_t action;
 855
 856         if (CMD_ARGC < 1) {
 857                 command_print(CMD_CTX, "stm32x mass_erase <STM32L4 bank>");
 858                 return ERROR_COMMAND_SYNTAX_ERROR;
 859         }
 860
 861         struct flash_bank *bank;
 862         int retval = CALL_COMMAND_HANDLER(flash_command_get_bank, 0, &bank);
 863         if (ERROR_OK != retval)
 864                 return retval;
 865
 866         action =  FLASH_MER1 |  FLASH_MER2;
 867         retval = stm32l4_mass_erase(bank, action);
 868         if (retval == ERROR_OK) {
 869                 /* set all sectors as erased */
 870                 for (i = 0; i < bank->num_sectors; i++)
 871                         bank->sectors[i].is_erased = 1;
 872
 873                 command_print(CMD_CTX, "stm32x mass erase complete");
 874         } else {
 875                 command_print(CMD_CTX, "stm32x mass erase failed");
 876         }
 877
 878         return retval;
 879 }
 880
 881 static const struct command_registration stm32l4_exec_command_handlers[] = {
 882         {
 883                 .name = "lock",
 884                 .handler = stm32l4_handle_lock_command,
 885                 .mode = COMMAND_EXEC,
 886                 .usage = "bank_id",
 887                 .help = "Lock entire flash device.",
 888         },
 889         {
 890                 .name = "unlock",
 891                 .handler = stm32l4_handle_unlock_command,
 892                 .mode = COMMAND_EXEC,
 893                 .usage = "bank_id",
 894                 .help = "Unlock entire protected flash device.",
 895         },
 896         {
 897                 .name = "mass_erase",
 898                 .handler = stm32l4_handle_mass_erase_command,
 899                 .mode = COMMAND_EXEC,
 900                 .usage = "bank_id",
 901                 .help = "Erase entire flash device.",
 902         },
 903         COMMAND_REGISTRATION_DONE
 904 };
 905
 906 static const struct command_registration stm32l4_command_handlers[] = {
 907         {
 908                 .name = "stm32l4x",
 909                 .mode = COMMAND_ANY,
 910                 .help = "stm32l4x flash command group",
 911                 .usage = "",
 912                 .chain = stm32l4_exec_command_handlers,
 913         },
 914         COMMAND_REGISTRATION_DONE
 915 };
 916
 917 struct flash_driver stm32l4x_flash = {
 918         .name = "stm32l4x",
 919         .commands = stm32l4_command_handlers,
 920         .flash_bank_command = stm32l4_flash_bank_command,
 921         .erase = stm32l4_erase,
 922         .protect = stm32l4_protect,
 923         .write = stm32l4_write,
 924         .read = default_flash_read,
 925         .probe = stm32l4_probe,
 926         .auto_probe = stm32l4_auto_probe,
 927         .erase_check = default_flash_blank_check,
 928         .protect_check = stm32l4_protect_check,
 929         .info = get_stm32l4_info,
 930 };