trezor-firmware/embed/trezorhal/flash.c

/*
 * This file is part of the TREZOR project, https://trezor.io/
 *
 * Copyright (c) SatoshiLabs
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include STM32_HAL_H

#include <string.h>

#include "common.h"
#include "flash.h"

// see docs/memory.md for more information

static const uint32_t FLASH_SECTOR_TABLE[FLASH_SECTOR_COUNT + 1] = {
    [0] = 0x08000000,   // - 0x08003FFF |  16 KiB
    [1] = 0x08004000,   // - 0x08007FFF |  16 KiB
    [2] = 0x08008000,   // - 0x0800BFFF |  16 KiB
    [3] = 0x0800C000,   // - 0x0800FFFF |  16 KiB
    [4] = 0x08010000,   // - 0x0801FFFF |  64 KiB
    [5] = 0x08020000,   // - 0x0803FFFF | 128 KiB
    [6] = 0x08040000,   // - 0x0805FFFF | 128 KiB
    [7] = 0x08060000,   // - 0x0807FFFF | 128 KiB
    [8] = 0x08080000,   // - 0x0809FFFF | 128 KiB
    [9] = 0x080A0000,   // - 0x080BFFFF | 128 KiB
    [10] = 0x080C0000,  // - 0x080DFFFF | 128 KiB
    [11] = 0x080E0000,  // - 0x080FFFFF | 128 KiB
    [12] = 0x08100000,  // - 0x08103FFF |  16 KiB
    [13] = 0x08104000,  // - 0x08107FFF |  16 KiB
    [14] = 0x08108000,  // - 0x0810BFFF |  16 KiB
    [15] = 0x0810C000,  // - 0x0810FFFF |  16 KiB
    [16] = 0x08110000,  // - 0x0811FFFF |  64 KiB
    [17] = 0x08120000,  // - 0x0813FFFF | 128 KiB
    [18] = 0x08140000,  // - 0x0815FFFF | 128 KiB
    [19] = 0x08160000,  // - 0x0817FFFF | 128 KiB
    [20] = 0x08180000,  // - 0x0819FFFF | 128 KiB
    [21] = 0x081A0000,  // - 0x081BFFFF | 128 KiB
    [22] = 0x081C0000,  // - 0x081DFFFF | 128 KiB
    [23] = 0x081E0000,  // - 0x081FFFFF | 128 KiB
    [24] = 0x08200000,  // last element - not a valid sector
};

const uint8_t FIRMWARE_SECTORS[FIRMWARE_SECTORS_COUNT] = {
    FLASH_SECTOR_FIRMWARE_START,
    7,
    8,
    9,
    10,
    FLASH_SECTOR_FIRMWARE_END,
    FLASH_SECTOR_FIRMWARE_EXTRA_START,
    18,
    19,
    20,
    21,
    22,
    FLASH_SECTOR_FIRMWARE_EXTRA_END,
};

const uint8_t STORAGE_SECTORS[STORAGE_SECTORS_COUNT] = {
    FLASH_SECTOR_STORAGE_1,
    FLASH_SECTOR_STORAGE_2,
};

void flash_init(void) {}

secbool flash_unlock_write(void) {
  HAL_FLASH_Unlock();
  FLASH->SR |= FLASH_STATUS_ALL_FLAGS;  // clear all status flags
  return sectrue;
}

secbool flash_lock_write(void) {
  HAL_FLASH_Lock();
  return sectrue;
}

const void *flash_get_address(uint8_t sector, uint32_t offset, uint32_t size) {
  if (sector >= FLASH_SECTOR_COUNT) {
    return NULL;
  }
  const uint32_t addr = FLASH_SECTOR_TABLE[sector] + offset;
  const uint32_t next = FLASH_SECTOR_TABLE[sector + 1];
  if (addr + size > next) {
    return NULL;
  }
  return (const void *)addr;
}

secbool flash_erase_sectors(const uint8_t *sectors, int len,
                            void (*progress)(int pos, int len)) {
  ensure(flash_unlock_write(), NULL);
  FLASH_EraseInitTypeDef EraseInitStruct;
  EraseInitStruct.TypeErase = FLASH_TYPEERASE_SECTORS;
  EraseInitStruct.VoltageRange = FLASH_VOLTAGE_RANGE_3;
  EraseInitStruct.NbSectors = 1;
  if (progress) {
    progress(0, len);
  }
  for (int i = 0; i < len; i++) {
    EraseInitStruct.Sector = sectors[i];
    uint32_t SectorError;
    if (HAL_FLASHEx_Erase(&EraseInitStruct, &SectorError) != HAL_OK) {
      ensure(flash_lock_write(), NULL);
      return secfalse;
    }
    // check whether the sector was really deleted (contains only 0xFF)
    const uint32_t addr_start = FLASH_SECTOR_TABLE[sectors[i]],
                   addr_end = FLASH_SECTOR_TABLE[sectors[i] + 1];
    for (uint32_t addr = addr_start; addr < addr_end; addr += 4) {
      if (*((const uint32_t *)addr) != 0xFFFFFFFF) {
        ensure(flash_lock_write(), NULL);
        return secfalse;
      }
    }
    if (progress) {
      progress(i + 1, len);
    }
  }
  ensure(flash_lock_write(), NULL);
  return sectrue;
}

secbool flash_write_byte(uint8_t sector, uint32_t offset, uint8_t data) {
  uint32_t address = (uint32_t)flash_get_address(sector, offset, 1);
  if (address == 0) {
    return secfalse;
  }
  if (data != (data & *((const uint8_t *)address))) {
    return secfalse;
  }
  if (HAL_OK != HAL_FLASH_Program(FLASH_TYPEPROGRAM_BYTE, address, data)) {
    return secfalse;
  }
  if (data != *((const uint8_t *)address)) {
    return secfalse;
  }
  return sectrue;
}

secbool flash_write_word(uint8_t sector, uint32_t offset, uint32_t data) {
  uint32_t address = (uint32_t)flash_get_address(sector, offset, 4);
  if (address == 0) {
    return secfalse;
  }
  if (offset % sizeof(uint32_t)) {  // we write only at 4-byte boundary
    return secfalse;
  }
  if (data != (data & *((const uint32_t *)address))) {
    return secfalse;
  }
  if (HAL_OK != HAL_FLASH_Program(FLASH_TYPEPROGRAM_WORD, address, data)) {
    return secfalse;
  }
  if (data != *((const uint32_t *)address)) {
    return secfalse;
  }
  return sectrue;
}

#define FLASH_OTP_LOCK_BASE 0x1FFF7A00U

secbool flash_otp_read(uint8_t block, uint8_t offset, uint8_t *data,
                       uint8_t datalen) {
  if (block >= FLASH_OTP_NUM_BLOCKS ||
      offset + datalen > FLASH_OTP_BLOCK_SIZE) {
    return secfalse;
  }
  for (uint8_t i = 0; i < datalen; i++) {
    data[i] = *(__IO uint8_t *)(FLASH_OTP_BASE + block * FLASH_OTP_BLOCK_SIZE +
                                offset + i);
  }
  return sectrue;
}

secbool flash_otp_write(uint8_t block, uint8_t offset, const uint8_t *data,
                        uint8_t datalen) {
  if (block >= FLASH_OTP_NUM_BLOCKS ||
      offset + datalen > FLASH_OTP_BLOCK_SIZE) {
    return secfalse;
  }
  ensure(flash_unlock_write(), NULL);
  for (uint8_t i = 0; i < datalen; i++) {
    uint32_t address =
        FLASH_OTP_BASE + block * FLASH_OTP_BLOCK_SIZE + offset + i;
    ensure(sectrue * (HAL_OK == HAL_FLASH_Program(FLASH_TYPEPROGRAM_BYTE,
                                                  address, data[i])),
           NULL);
  }
  ensure(flash_lock_write(), NULL);
  return sectrue;
}

secbool flash_otp_lock(uint8_t block) {
  if (block >= FLASH_OTP_NUM_BLOCKS) {
    return secfalse;
  }
  ensure(flash_unlock_write(), NULL);
  HAL_StatusTypeDef ret = HAL_FLASH_Program(FLASH_TYPEPROGRAM_BYTE,
                                            FLASH_OTP_LOCK_BASE + block, 0x00);
  ensure(flash_lock_write(), NULL);
  return sectrue * (ret == HAL_OK);
}

secbool flash_otp_is_locked(uint8_t block) {
  return sectrue * (0x00 == *(__IO uint8_t *)(FLASH_OTP_LOCK_BASE + block));
}