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-rw-r--r--os/hal/complex/mfs/mfs.c1203
-rw-r--r--os/hal/complex/mfs/mfs.h370
-rw-r--r--os/hal/complex/mfs/mfs.mk5
-rw-r--r--os/hal/complex/readme.txt6
4 files changed, 1584 insertions, 0 deletions
diff --git a/os/hal/complex/mfs/mfs.c b/os/hal/complex/mfs/mfs.c
new file mode 100644
index 000000000..6f44032ce
--- /dev/null
+++ b/os/hal/complex/mfs/mfs.c
@@ -0,0 +1,1203 @@
+/*
+ Managed Flash Storage - Copyright (C) 2016 Giovanni Di Sirio
+
+ This file is part of ChibiOS.
+
+ ChibiOS 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.
+
+ ChibiOS 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/>.
+*/
+
+/**
+ * @file mfs.c
+ * @brief Managed Flash Storage module code.
+ * @details This module manages a flash partition as a generic storage where
+ * arbitrary data records can be created, updated, deleted and
+ * retrieved.<br>
+ * A managed partition is composed of two banks of equal size, a
+ * bank is composed of one or more erasable sectors, a sector is
+ * divided in writable pages.<br>
+ * The module handles flash wear leveling and recovery of damaged
+ * banks (where possible) caused by power loss during operations.
+ * Both operations are transparent to the user.
+ *
+ * @addtogroup mfs
+ * @{
+ */
+
+#include "hal.h"
+
+#include "mfs.h"
+
+/*===========================================================================*/
+/* Driver local definitions. */
+/*===========================================================================*/
+
+#define PAIR(a, b) (((unsigned)(a) << 2U) | (unsigned)(b))
+
+/**
+ * @brief Error check helper.
+ */
+#define RET_ON_ERROR(err) do { \
+ mfs_error_t e = (err); \
+ if (e != MFS_NO_ERROR) { \
+ return e; \
+ } \
+} while (false)
+
+/*===========================================================================*/
+/* Driver exported variables. */
+/*===========================================================================*/
+
+/*===========================================================================*/
+/* Driver local variables and types. */
+/*===========================================================================*/
+
+static const uint16_t crc16_table[256] = {
+ 0x0000, 0x1021, 0x2042, 0x3063, 0x4084, 0x50A5, 0x60C6, 0x70E7,
+ 0x8108, 0x9129, 0xA14A, 0xB16B, 0xC18C, 0xD1AD, 0xE1CE, 0xF1EF,
+ 0x1231, 0x0210, 0x3273, 0x2252, 0x52B5, 0x4294, 0x72F7, 0x62D6,
+ 0x9339, 0x8318, 0xB37B, 0xA35A, 0xD3BD, 0xC39C, 0xF3FF, 0xE3DE,
+ 0x2462, 0x3443, 0x0420, 0x1401, 0x64E6, 0x74C7, 0x44A4, 0x5485,
+ 0xA56A, 0xB54B, 0x8528, 0x9509, 0xE5EE, 0xF5CF, 0xC5AC, 0xD58D,
+ 0x3653, 0x2672, 0x1611, 0x0630, 0x76D7, 0x66F6, 0x5695, 0x46B4,
+ 0xB75B, 0xA77A, 0x9719, 0x8738, 0xF7DF, 0xE7FE, 0xD79D, 0xC7BC,
+ 0x48C4, 0x58E5, 0x6886, 0x78A7, 0x0840, 0x1861, 0x2802, 0x3823,
+ 0xC9CC, 0xD9ED, 0xE98E, 0xF9AF, 0x8948, 0x9969, 0xA90A, 0xB92B,
+ 0x5AF5, 0x4AD4, 0x7AB7, 0x6A96, 0x1A71, 0x0A50, 0x3A33, 0x2A12,
+ 0xDBFD, 0xCBDC, 0xFBBF, 0xEB9E, 0x9B79, 0x8B58, 0xBB3B, 0xAB1A,
+ 0x6CA6, 0x7C87, 0x4CE4, 0x5CC5, 0x2C22, 0x3C03, 0x0C60, 0x1C41,
+ 0xEDAE, 0xFD8F, 0xCDEC, 0xDDCD, 0xAD2A, 0xBD0B, 0x8D68, 0x9D49,
+ 0x7E97, 0x6EB6, 0x5ED5, 0x4EF4, 0x3E13, 0x2E32, 0x1E51, 0x0E70,
+ 0xFF9F, 0xEFBE, 0xDFDD, 0xCFFC, 0xBF1B, 0xAF3A, 0x9F59, 0x8F78,
+ 0x9188, 0x81A9, 0xB1CA, 0xA1EB, 0xD10C, 0xC12D, 0xF14E, 0xE16F,
+ 0x1080, 0x00A1, 0x30C2, 0x20E3, 0x5004, 0x4025, 0x7046, 0x6067,
+ 0x83B9, 0x9398, 0xA3FB, 0xB3DA, 0xC33D, 0xD31C, 0xE37F, 0xF35E,
+ 0x02B1, 0x1290, 0x22F3, 0x32D2, 0x4235, 0x5214, 0x6277, 0x7256,
+ 0xB5EA, 0xA5CB, 0x95A8, 0x8589, 0xF56E, 0xE54F, 0xD52C, 0xC50D,
+ 0x34E2, 0x24C3, 0x14A0, 0x0481, 0x7466, 0x6447, 0x5424, 0x4405,
+ 0xA7DB, 0xB7FA, 0x8799, 0x97B8, 0xE75F, 0xF77E, 0xC71D, 0xD73C,
+ 0x26D3, 0x36F2, 0x0691, 0x16B0, 0x6657, 0x7676, 0x4615, 0x5634,
+ 0xD94C, 0xC96D, 0xF90E, 0xE92F, 0x99C8, 0x89E9, 0xB98A, 0xA9AB,
+ 0x5844, 0x4865, 0x7806, 0x6827, 0x18C0, 0x08E1, 0x3882, 0x28A3,
+ 0xCB7D, 0xDB5C, 0xEB3F, 0xFB1E, 0x8BF9, 0x9BD8, 0xABBB, 0xBB9A,
+ 0x4A75, 0x5A54, 0x6A37, 0x7A16, 0x0AF1, 0x1AD0, 0x2AB3, 0x3A92,
+ 0xFD2E, 0xED0F, 0xDD6C, 0xCD4D, 0xBDAA, 0xAD8B, 0x9DE8, 0x8DC9,
+ 0x7C26, 0x6C07, 0x5C64, 0x4C45, 0x3CA2, 0x2C83, 0x1CE0, 0x0CC1,
+ 0xEF1F, 0xFF3E, 0xCF5D, 0xDF7C, 0xAF9B, 0xBFBA, 0x8FD9, 0x9FF8,
+ 0x6E17, 0x7E36, 0x4E55, 0x5E74, 0x2E93, 0x3EB2, 0x0ED1, 0x1EF0
+};
+
+/*===========================================================================*/
+/* Driver local functions. */
+/*===========================================================================*/
+
+uint16_t crc16(uint16_t crc, const uint8_t *data, size_t n) {
+
+ while (n > 0U) {
+ crc = (crc << 8U) ^ crc16_table[(crc >> 8U) ^ (uint16_t)*data];
+ data++;
+ n--;
+ }
+
+ return crc;
+}
+
+static void mfs_state_reset(MFSDriver *mfsp) {
+ unsigned i;
+
+ mfsp->current_bank = MFS_BANK_0;
+ mfsp->current_counter = 0U;
+ mfsp->next_offset = 0U;
+ mfsp->used_space = 0U;
+
+ for (i = 0; i < MFS_CFG_MAX_RECORDS; i++) {
+ mfsp->descriptors[i].offset = 0U;
+ mfsp->descriptors[i].size = 0U;
+ }
+}
+
+static flash_offset_t mfs_flash_get_bank_offset(MFSDriver *mfsp,
+ mfs_bank_t bank) {
+
+ return bank == MFS_BANK_0 ? flashGetSectorOffset(mfsp->config->flashp,
+ mfsp->config->bank0_start) :
+ flashGetSectorOffset(mfsp->config->flashp,
+ mfsp->config->bank1_start);
+}
+
+/**
+ * @brief Flash read.
+ *
+ * @param[in] mfsp pointer to the @p MFSDriver object
+ * @param[in] offset flash offset
+ * @param[in] n number of bytes to be read
+ * @param[out] rp pointer to the data buffer
+ * @return The operation status.
+ * @retval MFS_NO_ERROR if the operation has been successfully completed.
+ * @retval MFS_ERR_FLASH_FAILURE if the flash memory is unusable because HW
+ * failures.
+ *
+ * @notapi
+ */
+static mfs_error_t mfs_flash_read(MFSDriver *mfsp, flash_offset_t offset,
+ size_t n, uint8_t *rp) {
+ flash_error_t ferr;
+
+ ferr = flashRead(mfsp->config->flashp, offset, n, rp);
+ if (ferr != FLASH_NO_ERROR) {
+ return MFS_ERR_FLASH_FAILURE;
+ }
+
+ return MFS_NO_ERROR;
+}
+
+/**
+ * @brief Flash write.
+ * @note If the option @p MFS_CFG_WRITE_VERIFY is enabled then the flash
+ * is also read back for verification.
+ *
+ * @param[in] mfsp pointer to the @p MFSDriver object
+ * @param[in] offset flash offset
+ * @param[in] n number of bytes to be written
+ * @param[in] wp pointer to the data buffer
+ * @return The operation status.
+ * @retval MFS_NO_ERROR if the operation has been successfully completed.
+ * @retval MFS_ERR_VERIFY if the verify operation failed.
+ * @retval MFS_ERR_FLASH_FAILURE if the flash memory is unusable because HW
+ * failures.
+ *
+ * @notapi
+ */
+static mfs_error_t mfs_flash_write(MFSDriver *mfsp,
+ flash_offset_t offset,
+ size_t n,
+ const uint8_t *wp) {
+ flash_error_t ferr;
+
+ ferr = flashProgram(mfsp->config->flashp, offset, n, wp);
+ if (ferr != FLASH_NO_ERROR) {
+ return MFS_ERR_FLASH_FAILURE;
+ }
+
+ /* TODO: Implement verify.*/
+
+ return MFS_NO_ERROR;
+}
+
+/**
+ * @brief Flash copy.
+ * @note If the option @p MFS_CFG_WRITE_VERIFY is enabled then the flash
+ * is also read back for verification.
+ *
+ * @param[in] mfsp pointer to the @p MFSDriver object
+ * @param[in] doffset destination flash offset
+ * @param[in] soffset source flash offset
+ * @param[in] n number of bytes to be copied
+ * @return The operation status.
+ * @retval MFS_NO_ERROR if the operation has been successfully completed.
+ * @retval MFS_ERR_FLASH_FAILURE if the flash memory is unusable because HW
+ * failures.
+ *
+ * @notapi
+ */
+static mfs_error_t mfs_flash_copy(MFSDriver *mfsp,
+ flash_offset_t doffset,
+ flash_offset_t soffset,
+ uint32_t n) {
+
+ /* Splitting the operation in smaller operations because the buffer is
+ small.*/
+ while (n > 0U) {
+ /* Data size that can be written in a single program page operation.*/
+ size_t chunk = (size_t)(((doffset | (MFS_CFG_BUFFER_SIZE - 1U)) + 1U) -
+ doffset);
+ if (chunk > n) {
+ chunk = n;
+ }
+
+ RET_ON_ERROR(mfs_flash_read(mfsp, soffset, chunk, mfsp->buffer.data));
+ RET_ON_ERROR(mfs_flash_write(mfsp, doffset, chunk, mfsp->buffer.data));
+
+ /* Next page.*/
+ soffset += chunk;
+ doffset += chunk;
+ n -= chunk;
+ }
+
+ return MFS_NO_ERROR;
+}
+
+/**
+ * @brief Verifies integrity of a record.
+ *
+ * @param[in] mfsp pointer to the @p MFSDriver object
+ * @param[in] dhdrp pointer to the header to be checked
+ * @param[in] offset flash offset of the header to be checked
+ * @param[in] limit flash limit offset
+ * @param[out] sts assessed record state
+ * @return The operation status.
+ * @retval MFS_NO_ERROR if the operation has been successfully completed.
+ * @retval MFS_ERR_FLASH_FAILURE if the flash memory is unusable because HW
+ * failures.
+ *
+ * @notapi
+ */
+static mfs_error_t mfs_record_check(MFSDriver *mfsp,
+ mfs_data_header_t *dhdrp,
+ flash_offset_t offset,
+ flash_offset_t limit,
+ mfs_record_state_t *sts) {
+ unsigned i;
+
+ for (i = 0; i < 3; i++) {
+ if (dhdrp->hdr32[i] != mfsp->config->erased) {
+ /* Not erased must verify the header.*/
+ if ((dhdrp->fields.magic != MFS_HEADER_MAGIC) ||
+ (dhdrp->fields.id < (uint16_t)1) ||
+ (dhdrp->fields.id > (uint16_t)MFS_CFG_MAX_RECORDS) ||
+ (dhdrp->fields.size + sizeof (mfs_data_header_t) > limit - offset)) {
+ *sts = MFS_RECORD_GARBAGE;
+ return MFS_NO_ERROR;
+ }
+#if MFS_CFG_STRONG_CHECKING == TRUE
+ {
+ /* Checking the CRC while reading the record data.*/
+ (void)mfsp;
+ }
+#else
+ (void)mfsp;
+#endif
+ }
+ }
+
+ /* It is fully erased.*/
+ *sts = MFS_RECORD_ERASED;
+ return MFS_NO_ERROR;
+}
+
+/**
+ * @brief Erases and verifies all sectors belonging to a bank.
+ *
+ * @param[in] mfsp pointer to the @p MFSDriver object
+ * @param[in] bank bank to be erased
+ * @return The operation status.
+ * @retval MFS_NO_ERROR if the operation has been successfully completed.
+ * @retval MFS_ERR_FLASH_FAILURE if the flash memory is unusable because HW
+ * failures.
+ *
+ * @notapi
+ */
+static mfs_error_t mfs_bank_erase(MFSDriver *mfsp, mfs_bank_t bank) {
+ flash_sector_t sector, end;
+
+ if (bank == MFS_BANK_0) {
+ sector = mfsp->config->bank0_start;
+ end = mfsp->config->bank0_start + mfsp->config->bank0_sectors;
+ }
+ else {
+ sector = mfsp->config->bank1_start;
+ end = mfsp->config->bank1_start + mfsp->config->bank1_sectors;
+ }
+
+ while (sector < end) {
+ flash_error_t ferr;
+
+ ferr = flashStartEraseSector(mfsp->config->flashp, sector);
+ if (ferr != FLASH_NO_ERROR) {
+ return MFS_ERR_FLASH_FAILURE;
+ }
+ ferr = flashWaitErase(mfsp->config->flashp);
+ if (ferr != FLASH_NO_ERROR) {
+ return MFS_ERR_FLASH_FAILURE;
+ }
+ ferr = flashVerifyErase(mfsp->config->flashp, sector);
+ if (ferr != FLASH_NO_ERROR) {
+ return MFS_ERR_FLASH_FAILURE;
+ }
+
+ sector++;
+ }
+
+ return MFS_NO_ERROR;
+}
+
+/**
+ * @brief Erases and verifies all sectors belonging to a bank.
+ *
+ * @param[in] mfsp pointer to the @p MFSDriver object
+ * @param[in] bank bank to be verified
+ * @return The operation status.
+ * @retval MFS_NO_ERROR if the operation has been successfully completed.
+ * @retval MFS_ERR_VERIFY if the bank is not erased
+ * @retval MFS_ERR_FLASH_FAILURE if the flash memory is unusable because HW
+ * failures.
+ *
+ * @notapi
+ */
+static mfs_error_t mfs_bank_verify_erase(MFSDriver *mfsp, mfs_bank_t bank) {
+ flash_sector_t sector, end;
+
+ if (bank == MFS_BANK_0) {
+ sector = mfsp->config->bank0_start;
+ end = mfsp->config->bank0_start + mfsp->config->bank0_sectors;
+ }
+ else {
+ sector = mfsp->config->bank1_start;
+ end = mfsp->config->bank1_start + mfsp->config->bank1_sectors;
+ }
+
+ while (sector < end) {
+ flash_error_t ferr;
+
+ ferr = flashVerifyErase(mfsp->config->flashp, sector);
+ if (ferr == FLASH_ERROR_VERIFY) {
+ return MFS_ERR_VERIFY;
+ }
+ if (ferr != FLASH_NO_ERROR) {
+ return MFS_ERR_FLASH_FAILURE;
+ }
+
+ sector++;
+ }
+
+ return MFS_NO_ERROR;
+}
+
+/**
+ * @brief Writes the validation header in a bank.
+ *
+ * @param[in] mfsp pointer to the @p MFSDriver object
+ * @param[in] bank bank to be validated
+ * @param[in] cnt value for the flash usage counter
+ * @return The operation status.
+ * @retval MFS_NO_ERROR if the operation has been successfully completed.
+ * @retval MFS_ERR_FLASH_FAILURE if the flash memory is unusable because HW
+ * failures.
+ *
+ * @notapi
+ */
+static mfs_error_t mfs_bank_write_header(MFSDriver *mfsp,
+ mfs_bank_t bank,
+ uint32_t cnt) {
+ flash_sector_t sector;
+ mfs_bank_header_t bhdr;
+
+ if (bank == MFS_BANK_0) {
+ sector = mfsp->config->bank0_start;
+ }
+ else {
+ sector = mfsp->config->bank1_start;
+ }
+
+ bhdr.fields.magic1 = MFS_BANK_MAGIC_1;
+ bhdr.fields.magic2 = MFS_BANK_MAGIC_2;
+ bhdr.fields.counter = cnt;
+ bhdr.fields.reserved1 = (uint16_t)mfsp->config->erased;
+ bhdr.fields.crc = crc16(0xFFFFU, bhdr.hdr8,
+ sizeof (mfs_bank_header_t) - sizeof (uint16_t));
+
+ return mfs_flash_write(mfsp,
+ flashGetSectorOffset(mfsp->config->flashp, sector),
+ sizeof (mfs_bank_header_t),
+ bhdr.hdr8);
+}
+
+/**
+ * @brief Scans blocks searching for records.
+ * @note The block integrity is strongly checked.
+ *
+ * @param[in] mfsp pointer to the @p MFSDriver object
+ * @param[in] bank the bank identifier
+ * @param[out] statep bank state
+ * @param[in] foundcb callback to be called for each found record or @p NULL
+ * @param[in] endcb callback to be called after scanning or @p NULL
+ *
+ * @return The operation status.
+ * @retval MFS_NO_ERROR if the operation has been successfully completed.
+ * @retval MFS_ERR_FLASH_FAILURE if the flash memory is unusable because HW
+ * failures.
+ */
+static mfs_error_t mfs_bank_scan_records(MFSDriver *mfsp,
+ mfs_bank_t bank,
+ mfs_bank_state_t *statep) {
+ flash_offset_t hdr_offset, start_offset, end_offset;
+ mfs_record_state_t sts;
+ bool warning = false;
+
+ start_offset = mfs_flash_get_bank_offset(mfsp, bank);
+ end_offset = start_offset + mfsp->config->bank_size;
+
+ /* Scanning records.*/
+ hdr_offset = start_offset + (flash_offset_t)sizeof(mfs_bank_header_t);
+ while (hdr_offset < end_offset) {
+ /* Reading the current record header.*/
+ RET_ON_ERROR(mfs_flash_read(mfsp, start_offset,
+ sizeof (mfs_data_header_t),
+ (void *)&mfsp->buffer.dhdr));
+
+ /* Checking header/data integrity.*/
+ RET_ON_ERROR(mfs_record_check(mfsp, &mfsp->buffer.dhdr,
+ hdr_offset, end_offset, &sts));
+ if (sts == MFS_RECORD_ERASED) {
+ /* Record area fully erased, stopping scan.*/
+ break;
+ }
+ else if (sts == MFS_RECORD_OK) {
+ /* Record OK.*/
+ uint32_t size = mfsp->buffer.dhdr.fields.size;
+
+ /* Zero-sized records are erase markers.*/
+ if (size == 0U) {
+ mfsp->descriptors[mfsp->buffer.dhdr.fields.id - 1].offset = 0U;
+ mfsp->descriptors[mfsp->buffer.dhdr.fields.id - 1].size = 0U;
+ }
+ else {
+ mfsp->descriptors[mfsp->buffer.dhdr.fields.id - 1].offset = hdr_offset;
+ mfsp->descriptors[mfsp->buffer.dhdr.fields.id - 1].size = size;
+ }
+ }
+ else if (sts == MFS_RECORD_CRC) {
+ /* Record payload corrupted, scan can continue because the header
+ is OK.*/
+ warning = true;
+ }
+ else {
+ /* Unrecognized header, scanning cannot continue.*/
+ warning = true;
+ break;
+ }
+ }
+
+ if (hdr_offset > end_offset) {
+ return MFS_ERR_INTERNAL;
+ }
+
+ /* Final.*/
+ mfsp->next_offset = hdr_offset;
+
+ if (warning) {
+ *statep = MFS_BANK_PARTIAL;
+ }
+ else {
+ *statep = MFS_BANK_OK;
+ }
+
+ return MFS_NO_ERROR;
+}
+
+/**
+ * @brief Selects a bank as current.
+ *
+ * @param[in] mfsp pointer to the @p MFSDriver object
+ * @param[in] bank bank to be scanned
+ * @param[out] statep bank state
+ * @return The operation status.
+ * @retval MFS_NO_ERROR if the operation has been successfully completed.
+ * @retval MFS_ERR_FLASH_FAILURE if the flash memory is unusable because HW
+ * failures.
+ *
+ * @notapi
+ */
+static mfs_error_t mfs_bank_mount(MFSDriver *mfsp,
+ mfs_bank_t bank,
+ mfs_bank_state_t *statep) {
+ unsigned i;
+ bool dirty;
+ mfs_error_t err;
+ uint16_t crc;
+
+ /* Resetting the bank state.*/
+ mfs_state_reset(mfsp);
+
+ /* Worst case is default.*/
+ *statep = MFS_BANK_GARBAGE;
+
+ /* Reading the current bank header.*/
+ RET_ON_ERROR(mfs_flash_read(mfsp, mfs_flash_get_bank_offset(mfsp, bank),
+ sizeof (mfs_bank_header_t),
+ (void *)&mfsp->buffer.bhdr));
+
+ /* Checking the special case where the header is erased.*/
+ dirty = false;
+ for (i = 0; i < 4; i++) {
+ if (mfsp->buffer.bhdr.hdr32[i] != mfsp->config->erased) {
+ dirty = true;
+ break;
+ }
+ }
+
+ /* If the header is erased then it could be the whole block erased.*/
+ if (!dirty) {
+ err = mfs_bank_verify_erase(mfsp, bank);
+ if (err == MFS_NO_ERROR) {
+ *statep = MFS_BANK_ERASED;
+ }
+ return MFS_NO_ERROR;
+ }
+
+ /* Checking header fields integrity.*/
+ if ((mfsp->buffer.bhdr.fields.magic1 != MFS_BANK_MAGIC_1) ||
+ (mfsp->buffer.bhdr.fields.magic2 != MFS_BANK_MAGIC_2) ||
+ (mfsp->buffer.bhdr.fields.counter == mfsp->config->erased) ||
+ (mfsp->buffer.bhdr.fields.reserved1 != (uint16_t)mfsp->config->erased)) {
+ return MFS_NO_ERROR;
+ }
+
+ /* Verifying header CRC.*/
+ crc = crc16(0xFFFFU, mfsp->buffer.bhdr.hdr8,
+ sizeof (mfs_bank_header_t) - sizeof (uint16_t));
+ if (crc != mfsp->buffer.bhdr.fields.crc) {
+ return MFS_NO_ERROR;
+ }
+
+ /* Header is OK, storing metadata.*/
+ mfsp->current_bank = bank;
+ mfsp->current_counter = mfsp->buffer.bhdr.fields.counter;
+
+ /* Scanning for the most recent instance of all records.*/
+ RET_ON_ERROR(mfs_bank_scan_records(mfsp, bank, statep));
+
+ /* Calculating the effective used size.*/
+ mfsp->used_space = sizeof (mfs_bank_header_t);
+ for (i = 0; i < MFS_CFG_MAX_RECORDS; i++) {
+ if (mfsp->descriptors[i].offset != 0U) {
+ mfsp->used_space += mfsp->descriptors[i].size + sizeof (mfs_data_header_t);
+ }
+ }
+
+ return MFS_NO_ERROR;
+}
+
+/**
+ * @brief Copies all records from a bank to another.
+ *
+ * @param[in] mfsp pointer to the @p MFSDriver object
+ * @param[in] sbank source bank
+ * @param[in] dbank destination bank
+ * @return The operation status.
+ * @retval MFS_NO_ERROR if the operation has been successfully completed.
+ * @retval MFS_ERR_FLASH_FAILURE if the flash memory is unusable because HW
+ * failures.
+ *
+ * @notapi
+ */
+static mfs_error_t mfs_bank_copy(MFSDriver *mfsp,
+ mfs_bank_t sbank,
+ mfs_bank_t dbank) {
+ unsigned i;
+ mfs_bank_state_t sts;
+ flash_offset_t dest_offset;
+
+ RET_ON_ERROR(mfs_bank_mount(mfsp, sbank, &sts));
+
+ /* Write address.*/
+ dest_offset = mfs_flash_get_bank_offset(mfsp, dbank) +
+ sizeof (mfs_bank_header_t);
+
+ /* Copying the most recent record instances only.*/
+ for (i = 0; i < MFS_CFG_MAX_RECORDS; i++) {
+ if (mfsp->descriptors[i].offset != 0) {
+ RET_ON_ERROR(mfs_flash_copy(mfsp, dest_offset,
+ mfsp->descriptors[i].offset,
+ mfsp->descriptors[i].size));
+ dest_offset += mfsp->descriptors[i].size;
+ }
+ }
+
+ return MFS_NO_ERROR;
+}
+
+/**
+ * @brief Performs a flash partition mount attempt.
+ *
+ * @param[in] mfsp pointer to the @p MFSDriver object
+ * @return The operation status.
+ * @retval MFS_NO_ERROR if the operation has been successfully completed.
+ * @retval MFS_WARN_REPAIR if the operation has been completed but a
+ * repair has been performed.
+ * @retval MFS_ERR_FLASH_FAILURE if the flash memory is unusable because HW
+ * failures.
+ *
+ * @api
+ */
+static mfs_error_t mfs_try_mount(MFSDriver *mfsp) {
+ mfs_bank_state_t sts, sts0, sts1;
+ uint32_t cnt0 = 0, cnt1 = 0;
+ mfs_error_t err;
+
+ /* Assessing the state of the two banks by trying to mount them.*/
+ RET_ON_ERROR(mfs_bank_mount(mfsp, MFS_BANK_0, &sts0));
+ cnt0 = mfsp->current_counter;
+ RET_ON_ERROR(mfs_bank_mount(mfsp, MFS_BANK_1, &sts1));
+ cnt1 = mfsp->current_counter;
+
+ /* Handling all possible scenarios, each one requires its own recovery
+ strategy.*/
+ switch (PAIR(sts0, sts1)) {
+
+ case PAIR(MFS_BANK_ERASED, MFS_BANK_ERASED):
+ /* Both banks erased, first initialization.*/
+ RET_ON_ERROR(mfs_bank_write_header(mfsp, MFS_BANK_0, 1));
+ RET_ON_ERROR(mfs_bank_mount(mfsp, MFS_BANK_0, &sts));
+ err = MFS_NO_ERROR;
+ break;
+
+ case PAIR(MFS_BANK_ERASED, MFS_BANK_OK):
+ /* Normal situation, bank one is used.*/
+ RET_ON_ERROR(mfs_bank_mount(mfsp, MFS_BANK_1, &sts)); /* Not necessary.*/
+ err = MFS_NO_ERROR;
+ break;
+
+ case PAIR(MFS_BANK_ERASED, MFS_BANK_PARTIAL):
+ /* Bank zero is erased, bank one has problems.*/
+ RET_ON_ERROR(mfs_bank_copy(mfsp, MFS_BANK_1, MFS_BANK_0));
+ RET_ON_ERROR(mfs_bank_write_header(mfsp, MFS_BANK_0, cnt1 + 1));
+ RET_ON_ERROR(mfs_bank_erase(mfsp, MFS_BANK_1));
+ RET_ON_ERROR(mfs_bank_mount(mfsp, MFS_BANK_0, &sts));
+ err = MFS_WARN_REPAIR;
+ break;
+
+ case PAIR(MFS_BANK_ERASED, MFS_BANK_GARBAGE):
+ /* Bank zero is erased, bank one is not readable.*/
+ RET_ON_ERROR(mfs_bank_erase(mfsp, MFS_BANK_1));
+ RET_ON_ERROR(mfs_bank_write_header(mfsp, MFS_BANK_0, 1));
+ RET_ON_ERROR(mfs_bank_mount(mfsp, MFS_BANK_0, &sts));
+ err = MFS_WARN_REPAIR;
+ break;
+
+ case PAIR(MFS_BANK_OK, MFS_BANK_ERASED):
+ /* Normal situation, bank zero is used.*/
+ RET_ON_ERROR(mfs_bank_mount(mfsp, MFS_BANK_0, &sts));
+ err = MFS_NO_ERROR;
+ break;
+
+ case PAIR(MFS_BANK_OK, MFS_BANK_OK):
+ /* Both banks appear to be valid but one must be newer, erasing the
+ older one.*/
+ if (cnt0 > cnt1) {
+ /* Bank 0 is newer.*/
+ RET_ON_ERROR(mfs_bank_erase(mfsp, MFS_BANK_1));
+ RET_ON_ERROR(mfs_bank_mount(mfsp, MFS_BANK_0, &sts));
+ }
+ else {
+ /* Bank 1 is newer.*/
+ RET_ON_ERROR(mfs_bank_erase(mfsp, MFS_BANK_0));
+ RET_ON_ERROR(mfs_bank_mount(mfsp, MFS_BANK_1, &sts)); /* Not necessary.*/
+ }
+ err = MFS_WARN_REPAIR;
+ break;
+
+ case PAIR(MFS_BANK_OK, MFS_BANK_PARTIAL):
+ /* Bank zero is normal, bank one has problems.*/
+ if (cnt0 > cnt1) {
+ /* Normal bank zero is more recent than the partial bank one, the
+ partial bank needs to be erased.*/
+ RET_ON_ERROR(mfs_bank_erase(mfsp, MFS_BANK_1));
+ RET_ON_ERROR(mfs_bank_mount(mfsp, MFS_BANK_0, &sts));
+ }
+ else {
+ /* Partial bank one is more recent than the normal bank zero.*/
+ RET_ON_ERROR(mfs_bank_erase(mfsp, MFS_BANK_0));
+ RET_ON_ERROR(mfs_bank_copy(mfsp, MFS_BANK_1, MFS_BANK_0));
+ RET_ON_ERROR(mfs_bank_write_header(mfsp, MFS_BANK_0, cnt1 + 1));
+ RET_ON_ERROR(mfs_bank_erase(mfsp, MFS_BANK_1));
+ RET_ON_ERROR(mfs_bank_mount(mfsp, MFS_BANK_0, &sts));
+ }
+ err = MFS_WARN_REPAIR;
+ break;
+
+ case PAIR(MFS_BANK_OK, MFS_BANK_GARBAGE):
+ /* Bank zero is normal, bank one is unreadable.*/
+ RET_ON_ERROR(mfs_bank_erase(mfsp, MFS_BANK_1));
+ RET_ON_ERROR(mfs_bank_mount(mfsp, MFS_BANK_0, &sts));
+ err = MFS_WARN_REPAIR;
+ break;
+
+ case PAIR(MFS_BANK_PARTIAL, MFS_BANK_ERASED):
+ /* Bank zero has problems, bank one is erased.*/
+ RET_ON_ERROR(mfs_bank_copy(mfsp, MFS_BANK_0, MFS_BANK_1));
+ RET_ON_ERROR(mfs_bank_write_header(mfsp, MFS_BANK_1, cnt0 + 1));
+ RET_ON_ERROR(mfs_bank_erase(mfsp, MFS_BANK_0));
+ RET_ON_ERROR(mfs_bank_mount(mfsp, MFS_BANK_1, &sts));
+ err = MFS_WARN_REPAIR;
+ break;
+
+ case PAIR(MFS_BANK_PARTIAL, MFS_BANK_OK):
+ /* Bank zero has problems, bank one is normal.*/
+ if (cnt1 > cnt0) {
+ /* Normal bank one is more recent than the partial bank zero, the
+ partial bank has to be erased.*/
+ RET_ON_ERROR(mfs_bank_erase(mfsp, MFS_BANK_0));
+ RET_ON_ERROR(mfs_bank_mount(mfsp, MFS_BANK_1, &sts)); /* Not necessary.*/
+ }
+ else {
+ /* Partial bank zero is more recent than the normal bank one.*/
+ RET_ON_ERROR(mfs_bank_erase(mfsp, MFS_BANK_1));
+ RET_ON_ERROR(mfs_bank_copy(mfsp, MFS_BANK_0, MFS_BANK_1));
+ RET_ON_ERROR(mfs_bank_write_header(mfsp, MFS_BANK_1, cnt0 + 1));
+ RET_ON_ERROR(mfs_bank_erase(mfsp, MFS_BANK_0));
+ RET_ON_ERROR(mfs_bank_mount(mfsp, MFS_BANK_1, &sts));
+ }
+ err = MFS_WARN_REPAIR;
+ break;
+
+ case PAIR(MFS_BANK_PARTIAL, MFS_BANK_PARTIAL):
+ /* Both banks have problems.*/
+ if (cnt0 > cnt1) {
+ /* Bank zero is newer, copying in bank one and using it.*/
+ RET_ON_ERROR(mfs_bank_erase(mfsp, MFS_BANK_1));
+ RET_ON_ERROR(mfs_bank_copy(mfsp, MFS_BANK_0, MFS_BANK_1));
+ RET_ON_ERROR(mfs_bank_write_header(mfsp, MFS_BANK_1, cnt0 + 1));
+ RET_ON_ERROR(mfs_bank_erase(mfsp, MFS_BANK_0));
+ RET_ON_ERROR(mfs_bank_mount(mfsp, MFS_BANK_1, &sts));
+ }
+ else {
+ /* Bank one is newer, copying in bank zero and using it.*/
+ RET_ON_ERROR(mfs_bank_erase(mfsp, MFS_BANK_0));
+ RET_ON_ERROR(mfs_bank_copy(mfsp, MFS_BANK_1, MFS_BANK_0));
+ RET_ON_ERROR(mfs_bank_write_header(mfsp, MFS_BANK_0, cnt1 + 1));
+ RET_ON_ERROR(mfs_bank_erase(mfsp, MFS_BANK_1));
+ RET_ON_ERROR(mfs_bank_mount(mfsp, MFS_BANK_0, &sts));
+ }
+ err = MFS_WARN_REPAIR;
+ break;
+
+ case PAIR(MFS_BANK_PARTIAL, MFS_BANK_GARBAGE):
+ /* Bank zero has problems, bank one is unreadable.*/
+ RET_ON_ERROR(mfs_bank_erase(mfsp, MFS_BANK_1));
+ RET_ON_ERROR(mfs_bank_copy(mfsp, MFS_BANK_0, MFS_BANK_1));
+ RET_ON_ERROR(mfs_bank_write_header(mfsp, MFS_BANK_1, cnt0 + 1));
+ RET_ON_ERROR(mfs_bank_erase(mfsp, MFS_BANK_0));
+ RET_ON_ERROR(mfs_bank_mount(mfsp, MFS_BANK_1, &sts));
+ err = MFS_WARN_REPAIR;
+ break;
+
+ case PAIR(MFS_BANK_GARBAGE, MFS_BANK_ERASED):
+ /* Bank zero is unreadable, bank one is erased.*/
+ RET_ON_ERROR(mfs_bank_erase(mfsp, MFS_BANK_1));
+ RET_ON_ERROR(mfs_bank_write_header(mfsp, MFS_BANK_0, 1));
+ RET_ON_ERROR(mfs_bank_mount(mfsp, MFS_BANK_0, &sts));
+ err = MFS_WARN_REPAIR;
+ break;
+
+ case PAIR(MFS_BANK_GARBAGE, MFS_BANK_OK):
+ /* Bank zero is unreadable, bank one is normal.*/
+ RET_ON_ERROR(mfs_bank_erase(mfsp, MFS_BANK_0));
+ RET_ON_ERROR(mfs_bank_mount(mfsp, MFS_BANK_1, &sts)); /* Not necessary.*/
+ err = MFS_WARN_REPAIR;
+ break;
+
+ case PAIR(MFS_BANK_GARBAGE, MFS_BANK_PARTIAL):
+ /* Bank zero is unreadable, bank one has problems.*/
+ RET_ON_ERROR(mfs_bank_erase(mfsp, MFS_BANK_0));
+ RET_ON_ERROR(mfs_bank_copy(mfsp, MFS_BANK_1, MFS_BANK_0));
+ RET_ON_ERROR(mfs_bank_write_header(mfsp, MFS_BANK_0, cnt0 + 1));
+ RET_ON_ERROR(mfs_bank_erase(mfsp, MFS_BANK_1));
+ RET_ON_ERROR(mfs_bank_mount(mfsp, MFS_BANK_0, &sts));
+ err = MFS_WARN_REPAIR;
+ break;
+
+ case PAIR(MFS_BANK_GARBAGE, MFS_BANK_GARBAGE):
+ /* Both banks are unreadable, reinitializing.*/
+ RET_ON_ERROR(mfs_bank_erase(mfsp, MFS_BANK_0));
+ RET_ON_ERROR(mfs_bank_erase(mfsp, MFS_BANK_1));
+ RET_ON_ERROR(mfs_bank_write_header(mfsp, MFS_BANK_0, 1));
+ RET_ON_ERROR(mfs_bank_mount(mfsp, MFS_BANK_0, &sts));
+ err = MFS_WARN_REPAIR;
+ break;
+
+ default:
+ osalSysHalt("internal error");
+ }
+
+ /* If the last mount reported an anomaly then this is an error
+ because the bank has just been checked/repaired.*/
+ if (sts != MFS_BANK_OK) {
+ mfs_state_reset(mfsp);
+ return MFS_ERR_FLASH_FAILURE;
+ }
+
+ return err;
+}
+
+/**
+ * @brief Enforces a garbage collection.
+ * @details Storage data is compacted into a single bank.
+ *
+ * @param[out] mfsp pointer to the @p MFSDriver object
+ * @return The operation status.
+ * @retval MFS_NO_ERROR if the operation has been successfully completed.
+ * @retval MFS_ERR_FLASH_FAILURE if the flash memory is unusable because HW
+ * failures.
+ *
+ * @notapi
+ */
+static mfs_error_t mfs_garbage_collect(MFSDriver *mfsp,
+ mfs_bank_state_t *statep) {
+
+ if (mfsp->current_bank == MFS_BANK_0) {
+ RET_ON_ERROR(mfs_bank_copy(mfsp, MFS_BANK_0, MFS_BANK_1));
+ RET_ON_ERROR(mfs_bank_write_header(mfsp, MFS_BANK_1,
+ mfsp->current_counter + 1U));
+ RET_ON_ERROR(mfs_bank_erase(mfsp, MFS_BANK_0));
+ RET_ON_ERROR(mfs_bank_mount(mfsp, MFS_BANK_1, statep));
+ }
+ else {
+ RET_ON_ERROR(mfs_bank_copy(mfsp, MFS_BANK_1, MFS_BANK_0));
+ RET_ON_ERROR(mfs_bank_write_header(mfsp, MFS_BANK_0,
+ mfsp->current_counter + 1U));
+ RET_ON_ERROR(mfs_bank_erase(mfsp, MFS_BANK_1));
+ RET_ON_ERROR(mfs_bank_mount(mfsp, MFS_BANK_0, statep));
+ }
+
+ return MFS_NO_ERROR;
+}
+
+/*===========================================================================*/
+/* Driver exported functions. */
+/*===========================================================================*/
+
+/**
+ * @brief Initializes an instance.
+ *
+ * @param[out] mfsp pointer to the @p MFSDriver object
+ *
+ * @init
+ */
+void mfsObjectInit(MFSDriver *mfsp) {
+
+ osalDbgCheck(mfsp != NULL);
+
+ mfsp->state = MFS_STOP;
+ mfsp->config = NULL;
+}
+
+/**
+ * @brief Configures and activates a MFS driver.
+ *
+ * @param[in] mfsp pointer to the @p MFSDriver object
+ * @param[in] config pointer to the configuration
+ *
+ * @api
+ */
+void mfsStart(MFSDriver *mfsp, const MFSConfig *config) {
+
+ osalDbgCheck((mfsp != NULL) && (config != NULL));
+ osalDbgAssert((mfsp->state == MFS_STOP) || (mfsp->state == MFS_READY),
+ "invalid state");
+
+ if (mfsp->state == MFS_STOP) {
+
+ mfsp->config = config;
+ mfsp->state = MFS_READY;
+ }
+}
+
+/**
+ * @brief Deactivates a MFS driver.
+ *
+ * @param[in] mfsp pointer to the @p MFSDriver object
+ *
+ * @api
+ */
+void mfsStop(MFSDriver *mfsp) {
+
+ osalDbgCheck(mfsp != NULL);
+ osalDbgAssert((mfsp->state == MFS_STOP) || (mfsp->state == MFS_READY),
+ "invalid state");
+
+ if (mfsp->state != MFS_STOP) {
+ mfsp->config = NULL;
+ mfs_state_reset(mfsp);
+ mfsp->state = MFS_STOP;
+ }
+}
+
+/**
+ * @brief Mounts a managed flash storage.
+ * @details This functions checks the storage internal state and eventually
+ * performs the required initialization or repair operations.
+ *
+ * @param[in] mfsp pointer to the @p MFSDriver object
+ * @return The operation status.
+ * @retval MFS_NO_ERROR if the operation has been successfully completed.
+ * @retval MFS_WARN_REPAIR if the operation has been completed but a
+ * repair has been performed.
+ * @retval MFS_ERR_FLASH_FAILURE if the flash memory is unusable because HW
+ * failures.
+ *
+ * @api
+ */
+mfs_error_t mfsMount(MFSDriver *mfsp) {
+ unsigned i;
+
+ osalDbgCheck(mfsp != NULL);
+ osalDbgAssert(mfsp->state == MFS_READY, "invalid state");
+
+ /* Attempting to mount the managed partition.*/
+ for (i = 0; i < MFS_CFG_MAX_REPAIR_ATTEMPTS; i++) {
+ mfs_error_t err;
+
+ err = mfs_try_mount(mfsp);
+ if (!MFS_IS_ERROR(err)) {
+ mfsp->state = MFS_MOUNTED;
+ return err;
+ }
+ }
+
+ return MFS_ERR_FLASH_FAILURE;
+}
+
+/**
+ * @brief Unmounts a managed flash storage.
+ */
+mfs_error_t mfsUnmount(MFSDriver *mfsp) {
+
+ osalDbgAssert(mfsp->state == MFS_MOUNTED, "invalid state");
+
+ mfs_state_reset(mfsp);
+ mfsp->state = MFS_READY;
+
+ return MFS_NO_ERROR;
+}
+
+/**
+ * @brief Destroys the state of the managed storage by erasing the flash.
+ *
+ * @param[in] mfsp pointer to the @p MFSDriver object
+ * @return The operation status.
+ * @retval MFS_NO_ERROR if the operation has been successfully completed.
+ * @retval MFS_ERR_FLASH_FAILURE if the flash memory is unusable because HW
+ * failures.
+ *
+ * @api
+ */
+mfs_error_t mfsErase(MFSDriver *mfsp) {
+
+ osalDbgCheck(mfsp != NULL);
+ osalDbgAssert(mfsp->state == MFS_READY, "invalid state");
+
+ RET_ON_ERROR(mfs_bank_erase(mfsp, MFS_BANK_0));
+ RET_ON_ERROR(mfs_bank_erase(mfsp, MFS_BANK_1));
+
+ return MFS_NO_ERROR;
+}
+
+/**
+ * @brief Retrieves and reads a data record.
+ *
+ * @param[in] mfsp pointer to the @p MFSDriver object
+ * @param[in] id record numeric identifier, the valid range is between
+ * @p 1 and @p MFS_CFG_MAX_RECORDS
+ * @param[in,out] np on input is the maximum buffer size, on return it is
+ * the size of the data copied into the buffer
+ * @param[out] buffer pointer to a buffer for record data
+ * @return The operation status.
+ * @retval MFS_NO_ERROR if the operation has been successfully completed.
+ * @retval MFS_ERR_NOT_FOUND if the specified id does not exists.
+ * @retval MFS_ERR_INV_SIZE if the passed buffer is not large enough to
+ * contain the record data.
+ * @retval MFS_ERR_CRC if retrieved data has a CRC error.
+ * @retval MFS_ERR_FLASH_FAILURE if the flash memory is unusable because HW
+ * failures.
+ *
+ * @api
+ */
+mfs_error_t mfsReadRecord(MFSDriver *mfsp, uint32_t id,
+ size_t *np, uint8_t *buffer) {
+ mfs_error_t err;
+
+ osalDbgCheck((mfsp != NULL) && (id >= 1) && (id <= MFS_CFG_MAX_RECORDS) &&
+ (np != NULL) && (buffer != NULL));
+ osalDbgAssert(mfsp->state == MFS_MOUNTED, "invalid state");
+
+ /* Marking the start of the operation.*/
+ mfsp->state = MFS_ACTIVE;
+
+ /* Checking if the requested record actually exists.*/
+ if (mfsp->descriptors[id].offset != 0U) {
+ /* Making sure to not overflow the buffer.*/
+ if (*np < mfsp->descriptors[id].size) {
+ err = MFS_ERR_INV_SIZE;
+ }
+ else {
+ /* Data read from flash.*/
+ *np = mfsp->descriptors[id].size;
+ err = mfs_flash_read(mfsp,
+ mfsp->descriptors[id].offset + sizeof (mfs_data_header_t),
+ *np,
+ buffer);
+
+ /* Checking CRC.*/
+ if (err == MFS_NO_ERROR) {
+ uint16_t crc = crc16(0xFFFFU, buffer, *np);
+ if (crc != mfsp->buffer.dhdr.fields.crc) {
+ err = MFS_ERR_CRC;
+ }
+ }
+ }
+ }
+ else {
+ err = MFS_ERR_NOT_FOUND;
+ }
+
+ /* Operation over.*/
+ mfsp->state = MFS_MOUNTED;
+
+ return err;
+}
+
+/**
+ * @brief Creates or updates a data record.
+ *
+ * @param[in] mfsp pointer to the @p MFSDriver object
+ * @param[in] id record numeric identifier, the valid range is between
+ * @p 1 and @p MFS_CFG_MAX_RECORDS
+ * @param[in] n size of data to be written, it cannot be zero
+ * @param[in] buffer pointer to a buffer for record data
+ * @return The operation status.
+ * @retval MFS_NO_ERROR if the operation has been successfully completed.
+ * @retval MFS_WARN_GC if the operation triggered a garbage collection.
+ * @retval MFS_ERR_OUT_OF_MEM if there is not enough flash space for the
+ * operation.
+ * @retval MFS_ERR_FLASH_FAILURE if the flash memory is unusable because HW
+ * failures.
+ *
+ * @api
+ */
+mfs_error_t mfsWriteRecord(MFSDriver *mfsp, uint32_t id,
+ size_t n, const uint8_t *buffer) {
+ flash_offset_t free, required;
+ mfs_bank_state_t sts;
+ bool warning = false;
+
+ osalDbgCheck((mfsp != NULL) && (id >= 1) && (id <= MFS_CFG_MAX_RECORDS) &&
+ (n > 0U) && (buffer != NULL));
+ osalDbgAssert(mfsp->state == MFS_MOUNTED, "invalid state");
+
+ /* Marking the start of the operation.*/
+ mfsp->state = MFS_ACTIVE;
+
+ /* If the required space is beyond the available (compacted) block
+ size then an error is returned.
+ NOTE: The space for one extra header is reserved in order to allow
+ for an erase operation after the space has been fully allocated.*/
+ required = ((flash_offset_t)sizeof (mfs_data_header_t) * 2U) +
+ (flash_offset_t)n;
+ if (required > mfsp->config->bank_size - mfsp->used_space) {
+ return MFS_ERR_OUT_OF_MEM;
+ }
+
+ /* Checking for immediately (not compacted) available space.*/
+ free = mfsp->config->bank_size - mfsp->next_offset;
+ if (required > free) {
+ /* We need to perform a garbage collection, there is enough space
+ but it has to be freed.*/
+ warning = true;
+ RET_ON_ERROR(mfs_garbage_collect(mfsp, &sts));
+ }
+
+ /* Writing the data header without the magic, it will be written last.*/
+ mfsp->buffer.dhdr.fields.magic = (uint32_t)mfsp->config->erased;
+ mfsp->buffer.dhdr.fields.id = (uint16_t)id;
+ mfsp->buffer.dhdr.fields.size = (uint32_t)n;
+ mfsp->buffer.dhdr.fields.crc = crc16(0xFFFFU, buffer, n);
+ RET_ON_ERROR(mfs_flash_write(mfsp,
+ mfsp->next_offset,
+ sizeof (mfs_data_header_t),
+ mfsp->buffer.data));
+
+ /* Writing the data part.*/
+ RET_ON_ERROR(mfs_flash_write(mfsp,
+ mfsp->next_offset + sizeof (mfs_data_header_t),
+ n,
+ buffer));
+
+ /* Finally writing the magic number, it seals the transaction.*/
+ mfsp->buffer.dhdr.fields.magic = (uint32_t)MFS_HEADER_MAGIC;
+ RET_ON_ERROR(mfs_flash_write(mfsp,
+ mfsp->next_offset,
+ sizeof (uint32_t),
+ mfsp->buffer.data));
+
+ /* Adjusting bank-related metadata.*/
+ mfsp->next_offset += sizeof (mfs_data_header_t) + n;
+ mfsp->used_space -= sizeof (mfs_data_header_t) + n;
+
+ /* Operation over.*/
+ mfsp->state = MFS_MOUNTED;
+
+ return warning ? MFS_WARN_GC : MFS_NO_ERROR;
+}
+
+/**
+ * @brief Erases a data record.
+ *
+ * @param[in] mfsp pointer to the @p MFSDriver object
+ * @param[in] id record numeric identifier, the valid range is between
+ * @p 1 and @p MFS_CFG_MAX_RECORDS
+ * @return The operation status.
+ * @retval MFS_NO_ERROR if the operation has been successfully completed.
+ * @retval MFS_ERR_FLASH_FAILURE if the flash memory is unusable because HW
+ * failures.
+ *
+ * @api
+ */
+mfs_error_t mfsEraseRecord(MFSDriver *mfsp, uint32_t id) {
+
+ osalDbgAssert(mfsp->state == MFS_MOUNTED, "invalid state");
+
+ /* Marking the start of the operation.*/
+ mfsp->state = MFS_ACTIVE;
+
+ (void)id;
+
+ /* Operation over.*/
+ mfsp->state = MFS_MOUNTED;
+
+ return MFS_NO_ERROR;
+}
+
+/**
+ * @brief Enforces a garbage collection operation.
+ * @details Garbage collection involves: integrity check, optionally repairs,
+ * obsolete data removal, data compaction and a flash bank swap.
+ *
+ * @param[in] mfsp pointer to the @p MFSDriver object
+ * @return The operation status.
+ * @retval MFS_NO_ERROR if the operation has been successfully completed.
+ * @retval MFS_WARN_REPAIR if the operation has been completed but a
+ * repair has been performed.
+ * @retval MFS_ERR_FLASH_FAILURE if the flash memory is unusable because HW
+ * failures.
+ *
+ * @api
+ */
+mfs_error_t mfsPerformGarbageCollection(MFSDriver *mfsp) {
+ mfs_error_t err;
+ mfs_bank_state_t sts;
+
+ osalDbgAssert(mfsp->state == MFS_MOUNTED, "invalid state");
+
+ /* Marking the start of the operation.*/
+ mfsp->state = MFS_ACTIVE;
+
+ err = mfs_garbage_collect(mfsp, &sts);
+
+ /* Operation over.*/
+ mfsp->state = MFS_MOUNTED;
+
+ return err;
+}
+
+/** @} */
diff --git a/os/hal/complex/mfs/mfs.h b/os/hal/complex/mfs/mfs.h
new file mode 100644
index 000000000..bfaa92681
--- /dev/null
+++ b/os/hal/complex/mfs/mfs.h
@@ -0,0 +1,370 @@
+/*
+ Managed Flash Storage - Copyright (C) 2016 Giovanni Di Sirio
+
+ This file is part of ChibiOS.
+
+ ChibiOS 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.
+
+ ChibiOS 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/>.
+*/
+
+/**
+ * @file mfs.h
+ * @brief Managed Flash Storage module header.
+ *
+ * @{
+ */
+
+#ifndef MFS_H
+#define MFS_H
+
+#include "hal_flash.h"
+
+/*===========================================================================*/
+/* Driver constants. */
+/*===========================================================================*/
+
+#define MFS_BANK_MAGIC_1 0xEC705ADEU
+#define MFS_BANK_MAGIC_2 0xF0339CC5U
+#define MFS_HEADER_MAGIC 0x5FAE45F0U
+
+/*===========================================================================*/
+/* Driver pre-compile time settings. */
+/*===========================================================================*/
+
+/**
+ * @name Configuration options
+ * @{
+ */
+/**
+ * @brief Maximum number of indexed records in the managed storage.
+ * @note Record indexes go from 0 to @p MFS_CFG_MAX_RECORDS - 1.
+ */
+#if !defined(MFS_CFG_MAX_RECORDS) || defined(__DOXYGEN__)
+#define MFS_CFG_MAX_RECORDS 32
+#endif
+
+/**
+ * @brief Maximum number of repair attempts on partition mount.
+ */
+#if !defined(MFS_CFG_MAX_REPAIR_ATTEMPTS) || defined(__DOXYGEN__)
+#define MFS_CFG_MAX_REPAIR_ATTEMPTS 3
+#endif
+
+/**
+ * @brief Verify written data.
+ */
+#if !defined(MFS_CFG_WRITE_VERIFY) || defined(__DOXYGEN__)
+#define MFS_CFG_WRITE_VERIFY TRUE
+#endif
+
+/**
+ * @brief Enables a stronger and slower check procedure on mount.
+ * @details Strong checking requires reading of the whole written data and
+ * this can be slow, normal checking only checks integrity of
+ * metadata, data errors would be detected on read.
+ */
+#if !defined(MFS_CFG_STRONG_CHECKING) || defined(__DOXYGEN__)
+#define MFS_CFG_STRONG_CHECKING TRUE
+#endif
+
+/**
+ * @brief Size of the buffer used for data copying.
+ * @note The buffer size must be a power of two and not smaller than
+ * 16 bytes.
+ * @note Larger buffers improve performance, buffers with size multiple
+ * of the flash program page size work better.
+ */
+#if !defined(MFS_CFG_BUFFER_SIZE) || defined(__DOXYGEN__)
+#define MFS_CFG_BUFFER_SIZE 32
+#endif
+/** @} */
+
+/*===========================================================================*/
+/* Derived constants and error checks. */
+/*===========================================================================*/
+
+#if MFS_CFG_MAX_RECORDS < 0
+#error "invalid MFS_CFG_MAX_RECORDS value"
+#endif
+
+#if (MFS_CFG_MAX_REPAIR_ATTEMPTS < 1) || (MFS_CFG_MAX_REPAIR_ATTEMPTS > 10)
+#error "invalid MFS_MAX_REPAIR_ATTEMPTS value"
+#endif
+
+#if (MFS_CFG_MAX_REPAIR_ATTEMPTS < 1) || (MFS_CFG_MAX_REPAIR_ATTEMPTS > 10)
+#error "invalid MFS_MAX_REPAIR_ATTEMPTS value"
+#endif
+
+#if MFS_CFG_BUFFER_SIZE <= 16
+#error "invalid MFS_CFG_BUFFER_SIZE value"
+#endif
+
+#if (MFS_CFG_BUFFER_SIZE & (MFS_CFG_BUFFER_SIZE - 1)) != 0
+#error "MFS_CFG_BUFFER_SIZE is not a power of two"
+#endif
+
+/*===========================================================================*/
+/* Driver data structures and types. */
+/*===========================================================================*/
+
+/**
+ * @brief Type of a flash bank.
+ */
+typedef enum {
+ MFS_BANK_0 = 0,
+ MFS_BANK_1 = 1
+} mfs_bank_t;
+
+/**
+ * @brief Type of driver state machine states.
+ */
+typedef enum {
+ MFS_UNINIT = 0,
+ MFS_STOP = 1,
+ MFS_READY = 2,
+ MFS_MOUNTED = 3,
+ MFS_ACTIVE = 4
+} mfs_state_t;
+
+/**
+ * @brief Type of an MFS error code.
+ * @note Errors are negative integers, informative warnings are positive
+ * integers.
+ */
+typedef enum {
+ MFS_NO_ERROR = 0,
+ MFS_WARN_REPAIR = 1,
+ MFS_WARN_GC = 2,
+ MFS_ERR_NOT_FOUND = -1,
+ MFS_ERR_INV_SIZE = -2,
+ MFS_ERR_VERIFY = -3,
+ MFS_ERR_CRC = -4,
+ MFS_ERR_HEADER = -5,
+ MFS_ERR_OUT_OF_MEM = -6,
+ MFS_ERR_FLASH_FAILURE = -7,
+ MFS_ERR_INTERNAL = -8
+} mfs_error_t;
+
+/**
+ * @brief Type of a bank state assessment.
+ */
+typedef enum {
+ MFS_BANK_ERASED = 0,
+ MFS_BANK_OK = 1,
+ MFS_BANK_PARTIAL = 2,
+ MFS_BANK_GARBAGE = 3
+} mfs_bank_state_t;
+
+/**
+ * @brief Type of a record state assessment.
+ */
+typedef enum {
+ MFS_RECORD_ERASED = 0,
+ MFS_RECORD_OK = 1,
+ MFS_RECORD_CRC = 2,
+ MFS_RECORD_GARBAGE = 3
+} mfs_record_state_t;
+
+/**
+ * @brief Type of a bank header.
+ * @note The header resides in the first 16 bytes of a bank.
+ */
+typedef union {
+ struct {
+ /**
+ * @brief Bank magic 1.
+ */
+ uint32_t magic1;
+ /**
+ * @brief Bank magic 2.
+ */
+ uint32_t magic2;
+ /**
+ * @brief Usage counter of the bank.
+ * @details This value is increased each time a bank swap is performed. It
+ * indicates how much wearing the flash has already endured.
+ */
+ uint32_t counter;
+ /**
+ * @brief Reserved field.
+ */
+ uint16_t reserved1;
+ /**
+ * @brief Header CRC.
+ */
+ uint16_t crc;
+ } fields;
+ uint8_t hdr8[16];
+ uint32_t hdr32[4];
+} mfs_bank_header_t;
+
+/**
+ * @brief Type of a data block header.
+ * @details This structure is placed before each written data block.
+ */
+typedef struct {
+ struct {
+ /**
+ * @brief Data header magic.
+ */
+ uint32_t magic;
+ /**
+ * @brief Data identifier.
+ */
+ uint16_t id;
+ /**
+ * @brief Data CRC.
+ */
+ uint16_t crc;
+ /**
+ * @brief Data size.
+ */
+ uint32_t size;
+ } fields;
+ uint8_t hdr8[12];
+ uint32_t hdr32[3];
+} mfs_data_header_t;
+
+typedef struct {
+ /**
+ * @brief Offset of the record header.
+ */
+ flash_offset_t offset;
+ /**
+ * @brief Record data size.
+ */
+ uint32_t size;
+} mfs_record_descriptor_t;
+
+/**
+ * @brief Type of a MFS configuration structure.
+ */
+typedef struct {
+ /**
+ * @brief Flash driver associated to this MFS instance.
+ */
+ BaseFlash *flashp;
+ /**
+ * @brief Erased value.
+ */
+ uint32_t erased;
+ /**
+ * @brief Banks size.
+ */
+ flash_offset_t bank_size;
+ /**
+ * @brief Base sector index for bank 0.
+ */
+ flash_sector_t bank0_start;
+ /**
+ * @brief Number of sectors for bank 0.
+ * @note The total size of bank0 sectors must be greater or equal to
+ * @p bank_size.
+ */
+ flash_sector_t bank0_sectors;
+ /**
+ * @brief Base sector index for bank 1.
+ */
+ flash_sector_t bank1_start;
+ /**
+ * @brief Number of sectors for bank 1.
+ * @note The total size of bank1 sectors must be greater or equal to
+ * @p bank_size.
+ */
+ flash_sector_t bank1_sectors;
+} MFSConfig;
+
+/**
+ * @extends BaseFlash
+ *
+ * @brief Type of an MFS instance.
+ */
+typedef struct {
+ /**
+ * @brief Driver state.
+ */
+ mfs_state_t state;
+ /**
+ * @brief Current configuration data.
+ */
+ const MFSConfig *config;
+ /**
+ * @brief Bank currently in use.
+ */
+ mfs_bank_t current_bank;
+ /**
+ * @brief Usage counter of the current bank.
+ */
+ uint32_t current_counter;
+ /**
+ * @brief Pointer to the next free position in the current bank.
+ */
+ flash_offset_t next_offset;
+ /**
+ * @brief Used space in the current bank without considering erased records.
+ */
+ flash_offset_t used_space;
+ /**
+ * @brief Offsets of the most recent instance of the records.
+ * @note Zero means that ther is not a record with that id.
+ */
+ mfs_record_descriptor_t descriptors[MFS_CFG_MAX_RECORDS];
+ /**
+ * @brief Transient buffer.
+ */
+ union {
+ mfs_data_header_t dhdr;
+ mfs_bank_header_t bhdr;
+ uint8_t data[MFS_CFG_BUFFER_SIZE];
+ } buffer;
+} MFSDriver;
+
+/*===========================================================================*/
+/* Driver macros. */
+/*===========================================================================*/
+
+/**
+ * @name Error codes handling macros
+ * @{
+ */
+#define MFS_IS_ERROR(err) ((err) < MFS_NO_ERROR)
+#define MFS_IS_WARNING(err) ((err) > MFS_NO_ERROR)
+/** @} */
+
+/*===========================================================================*/
+/* External declarations. */
+/*===========================================================================*/
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+ void mfsObjectInit(MFSDriver *devp);
+ void mfsStart(MFSDriver *devp, const MFSConfig *config);
+ void mfsStop(MFSDriver *devp);
+ mfs_error_t mfsMount(MFSDriver *devp);
+ mfs_error_t mfsUnmount(MFSDriver *devp);
+ mfs_error_t mfsErase(MFSDriver *mfsp);
+ mfs_error_t mfsReadRecord(MFSDriver *devp, uint32_t id,
+ size_t *np, uint8_t *buffer);
+ mfs_error_t mfsWriteRecord(MFSDriver *devp, uint32_t id,
+ size_t n, const uint8_t *buffer);
+ mfs_error_t mfsEraseRecord(MFSDriver *devp, uint32_t id);
+ mfs_error_t mfsPerformGarbageCollection(MFSDriver *mfsp);
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* MFS_H */
+
+/** @} */
+
diff --git a/os/hal/complex/mfs/mfs.mk b/os/hal/complex/mfs/mfs.mk
new file mode 100644
index 000000000..200655196
--- /dev/null
+++ b/os/hal/complex/mfs/mfs.mk
@@ -0,0 +1,5 @@
+# List of all the MFS subsystem files.
+MFSSRC := $(CHIBIOS)/os/hal/complex/mfs/mfs.c
+
+# Required include directories
+MFSINC := $(CHIBIOS)/os/hal/complex/mfs \ No newline at end of file
diff --git a/os/hal/complex/readme.txt b/os/hal/complex/readme.txt
new file mode 100644
index 000000000..fafdfacec
--- /dev/null
+++ b/os/hal/complex/readme.txt
@@ -0,0 +1,6 @@
+This directory contains complex drivers subsystems. Complex Drivers must
+abide to the following rules:
+- Must use HAL and OSAL only.
+- Cannot use RTOS functionalities.
+- Cannot use HW resources directly.
+- Must not use non-standard C language features.