diff options
Diffstat (limited to 'platforms/chibios/drivers/eeprom/eeprom_stm32.c')
| -rw-r--r-- | platforms/chibios/drivers/eeprom/eeprom_stm32.c | 629 |
1 files changed, 629 insertions, 0 deletions
diff --git a/platforms/chibios/drivers/eeprom/eeprom_stm32.c b/platforms/chibios/drivers/eeprom/eeprom_stm32.c new file mode 100644 index 0000000000..1a354dc213 --- /dev/null +++ b/platforms/chibios/drivers/eeprom/eeprom_stm32.c @@ -0,0 +1,629 @@ +/* + * This software is experimental and a work in progress. + * Under no circumstances should these files be used in relation to any critical system(s). + * Use of these files is at your own risk. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, + * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR + * PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE + * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, + * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER + * DEALINGS IN THE SOFTWARE. + * + * This files are free to use from http://engsta.com/stm32-flash-memory-eeprom-emulator/ by + * Artur F. + * + * Modifications for QMK and STM32F303 by Yiancar + * Modifications to add flash wear leveling by Ilya Zhuravlev + * Modifications to increase flash density by Don Kjer + */ + +#include <stdio.h> +#include <stdbool.h> +#include "util.h" +#include "debug.h" +#include "eeprom_stm32.h" +#include "flash_stm32.h" + +/* + * We emulate eeprom by writing a snapshot compacted view of eeprom contents, + * followed by a write log of any change since that snapshot: + * + * === SIMULATED EEPROM CONTENTS === + * + * ┌─ Compacted ┬ Write Log ─┐ + * │............│[BYTE][BYTE]│ + * │FFFF....FFFF│[WRD0][WRD1]│ + * │FFFFFFFFFFFF│[WORD][NEXT]│ + * │....FFFFFFFF│[BYTE][WRD0]│ + * ├────────────┼────────────┤ + * └──PAGE_BASE │ │ + * PAGE_LAST─┴─WRITE_BASE │ + * WRITE_LAST ┘ + * + * Compacted contents are the 1's complement of the actual EEPROM contents. + * e.g. An 'FFFF' represents a '0000' value. + * + * The size of the 'compacted' area is equal to the size of the 'emulated' eeprom. + * The size of the compacted-area and write log are configurable, and the combined + * size of Compacted + WriteLog is a multiple FEE_PAGE_SIZE, which is MCU dependent. + * Simulated Eeprom contents are located at the end of available flash space. + * + * The following configuration defines can be set: + * + * FEE_PAGE_COUNT # Total number of pages to use for eeprom simulation (Compact + Write log) + * FEE_DENSITY_BYTES # Size of simulated eeprom. (Defaults to half the space allocated by FEE_PAGE_COUNT) + * NOTE: The current implementation does not include page swapping, + * and FEE_DENSITY_BYTES will consume that amount of RAM as a cached view of actual EEPROM contents. + * + * The maximum size of FEE_DENSITY_BYTES is currently 16384. The write log size equals + * FEE_PAGE_COUNT * FEE_PAGE_SIZE - FEE_DENSITY_BYTES. + * The larger the write log, the less frequently the compacted area needs to be rewritten. + * + * + * *** General Algorithm *** + * + * During initialization: + * The contents of the Compacted-flash area are loaded and the 1's complement value + * is cached into memory (e.g. 0xFFFF in Flash represents 0x0000 in cache). + * Write log entries are processed until a 0xFFFF is reached. + * Each log entry updates a byte or word in the cache. + * + * During reads: + * EEPROM contents are given back directly from the cache in memory. + * + * During writes: + * The contents of the cache is updated first. + * If the Compacted-flash area corresponding to the write address is unprogrammed, the 1's complement of the value is written directly into Compacted-flash + * Otherwise: + * If the write log is full, erase both the Compacted-flash area and the Write log, then write cached contents to the Compacted-flash area. + * Otherwise a Write log entry is constructed and appended to the next free position in the Write log. + * + * + * *** Write Log Structure *** + * + * Write log entries allow for optimized byte writes to addresses below 128. Writing 0 or 1 words are also optimized when word-aligned. + * + * === WRITE LOG ENTRY FORMATS === + * + * ╔═══ Byte-Entry ══╗ + * ║0XXXXXXX║YYYYYYYY║ + * ║ └──┬──┘║└──┬───┘║ + * ║ Address║ Value ║ + * ╚════════╩════════╝ + * 0 <= Address < 0x80 (128) + * + * ╔ Word-Encoded 0 ╗ + * ║100XXXXXXXXXXXXX║ + * ║ │└─────┬─────┘║ + * ║ │Address >> 1 ║ + * ║ └── Value: 0 ║ + * ╚════════════════╝ + * 0 <= Address <= 0x3FFE (16382) + * + * ╔ Word-Encoded 1 ╗ + * ║101XXXXXXXXXXXXX║ + * ║ │└─────┬─────┘║ + * ║ │Address >> 1 ║ + * ║ └── Value: 1 ║ + * ╚════════════════╝ + * 0 <= Address <= 0x3FFE (16382) + * + * ╔═══ Reserved ═══╗ + * ║110XXXXXXXXXXXXX║ + * ╚════════════════╝ + * + * ╔═══════════ Word-Next ═══════════╗ + * ║111XXXXXXXXXXXXX║YYYYYYYYYYYYYYYY║ + * ║ └─────┬─────┘║└───────┬──────┘║ + * ║(Address-128)>>1║ ~Value ║ + * ╚════════════════╩════════════════╝ + * ( 0 <= Address < 0x0080 (128): Reserved) + * 0x80 <= Address <= 0x3FFE (16382) + * + * Write Log entry ranges: + * 0x0000 ... 0x7FFF - Byte-Entry; address is (Entry & 0x7F00) >> 4; value is (Entry & 0xFF) + * 0x8000 ... 0x9FFF - Word-Encoded 0; address is (Entry & 0x1FFF) << 1; value is 0 + * 0xA000 ... 0xBFFF - Word-Encoded 1; address is (Entry & 0x1FFF) << 1; value is 1 + * 0xC000 ... 0xDFFF - Reserved + * 0xE000 ... 0xFFBF - Word-Next; address is (Entry & 0x1FFF) << 1 + 0x80; value is ~(Next_Entry) + * 0xFFC0 ... 0xFFFE - Reserved + * 0xFFFF - Unprogrammed + * + */ + +#include "eeprom_stm32_defs.h" +/* These bits are used for optimizing encoding of bytes, 0 and 1 */ +#define FEE_WORD_ENCODING 0x8000 +#define FEE_VALUE_NEXT 0x6000 +#define FEE_VALUE_RESERVED 0x4000 +#define FEE_VALUE_ENCODED 0x2000 +#define FEE_BYTE_RANGE 0x80 + +/* Flash word value after erase */ +#define FEE_EMPTY_WORD ((uint16_t)0xFFFF) + +#if !defined(FEE_PAGE_SIZE) || !defined(FEE_PAGE_COUNT) || !defined(FEE_MCU_FLASH_SIZE) || !defined(FEE_PAGE_BASE_ADDRESS) +# error "not implemented." +#endif + +/* In-memory contents of emulated eeprom for faster access */ +/* *TODO: Implement page swapping */ +static uint16_t WordBuf[FEE_DENSITY_BYTES / 2]; +static uint8_t *DataBuf = (uint8_t *)WordBuf; + +/* Pointer to the first available slot within the write log */ +static uint16_t *empty_slot; + +// #define DEBUG_EEPROM_OUTPUT + +/* + * Debug print utils + */ + +#if defined(DEBUG_EEPROM_OUTPUT) + +# define debug_eeprom debug_enable +# define eeprom_println(s) println(s) +# define eeprom_printf(fmt, ...) xprintf(fmt, ##__VA_ARGS__); + +#else /* NO_DEBUG */ + +# define debug_eeprom false +# define eeprom_println(s) +# define eeprom_printf(fmt, ...) + +#endif /* NO_DEBUG */ + +void print_eeprom(void) { +#ifndef NO_DEBUG + int empty_rows = 0; + for (uint16_t i = 0; i < FEE_DENSITY_BYTES; i++) { + if (i % 16 == 0) { + if (i >= FEE_DENSITY_BYTES - 16) { + /* Make sure we display the last row */ + empty_rows = 0; + } + /* Check if this row is uninitialized */ + ++empty_rows; + for (uint16_t j = 0; j < 16; j++) { + if (DataBuf[i + j]) { + empty_rows = 0; + break; + } + } + if (empty_rows > 1) { + /* Repeat empty row */ + if (empty_rows == 2) { + /* Only display the first repeat empty row */ + println("*"); + } + i += 15; + continue; + } + xprintf("%04x", i); + } + if (i % 8 == 0) print(" "); + + xprintf(" %02x", DataBuf[i]); + if ((i + 1) % 16 == 0) { + println(""); + } + } +#endif +} + +uint16_t EEPROM_Init(void) { + /* Load emulated eeprom contents from compacted flash into memory */ + uint16_t *src = (uint16_t *)FEE_COMPACTED_BASE_ADDRESS; + uint16_t *dest = (uint16_t *)DataBuf; + for (; src < (uint16_t *)FEE_COMPACTED_LAST_ADDRESS; ++src, ++dest) { + *dest = ~*src; + } + + if (debug_eeprom) { + println("EEPROM_Init Compacted Pages:"); + print_eeprom(); + println("EEPROM_Init Write Log:"); + } + + /* Replay write log */ + uint16_t *log_addr; + for (log_addr = (uint16_t *)FEE_WRITE_LOG_BASE_ADDRESS; log_addr < (uint16_t *)FEE_WRITE_LOG_LAST_ADDRESS; ++log_addr) { + uint16_t address = *log_addr; + if (address == FEE_EMPTY_WORD) { + break; + } + /* Check for lowest 128-bytes optimization */ + if (!(address & FEE_WORD_ENCODING)) { + uint8_t bvalue = (uint8_t)address; + address >>= 8; + DataBuf[address] = bvalue; + eeprom_printf("DataBuf[0x%02x] = 0x%02x;\n", address, bvalue); + } else { + uint16_t wvalue; + /* Check if value is in next word */ + if ((address & FEE_VALUE_NEXT) == FEE_VALUE_NEXT) { + /* Read value from next word */ + if (++log_addr >= (uint16_t *)FEE_WRITE_LOG_LAST_ADDRESS) { + break; + } + wvalue = ~*log_addr; + if (!wvalue) { + eeprom_printf("Incomplete write at log_addr: 0x%04lx;\n", (uint32_t)log_addr); + /* Possibly incomplete write. Ignore and continue */ + continue; + } + address &= 0x1FFF; + address <<= 1; + /* Writes to addresses less than 128 are byte log entries */ + address += FEE_BYTE_RANGE; + } else { + /* Reserved for future use */ + if (address & FEE_VALUE_RESERVED) { + eeprom_printf("Reserved encoded value at log_addr: 0x%04lx;\n", (uint32_t)log_addr); + continue; + } + /* Optimization for 0 or 1 values. */ + wvalue = (address & FEE_VALUE_ENCODED) >> 13; + address &= 0x1FFF; + address <<= 1; + } + if (address < FEE_DENSITY_BYTES) { + eeprom_printf("DataBuf[0x%04x] = 0x%04x;\n", address, wvalue); + *(uint16_t *)(&DataBuf[address]) = wvalue; + } else { + eeprom_printf("DataBuf[0x%04x] cannot be set to 0x%04x [BAD ADDRESS]\n", address, wvalue); + } + } + } + + empty_slot = log_addr; + + if (debug_eeprom) { + println("EEPROM_Init Final DataBuf:"); + print_eeprom(); + } + + return FEE_DENSITY_BYTES; +} + +/* Clear flash contents (doesn't touch in-memory DataBuf) */ +static void eeprom_clear(void) { + FLASH_Unlock(); + + for (uint16_t page_num = 0; page_num < FEE_PAGE_COUNT; ++page_num) { + eeprom_printf("FLASH_ErasePage(0x%04lx)\n", (uint32_t)(FEE_PAGE_BASE_ADDRESS + (page_num * FEE_PAGE_SIZE))); + FLASH_ErasePage(FEE_PAGE_BASE_ADDRESS + (page_num * FEE_PAGE_SIZE)); + } + + FLASH_Lock(); + + empty_slot = (uint16_t *)FEE_WRITE_LOG_BASE_ADDRESS; + eeprom_printf("eeprom_clear empty_slot: 0x%08lx\n", (uint32_t)empty_slot); +} + +/* Erase emulated eeprom */ +void EEPROM_Erase(void) { + eeprom_println("EEPROM_Erase"); + /* Erase compacted pages and write log */ + eeprom_clear(); + /* re-initialize to reset DataBuf */ + EEPROM_Init(); +} + +/* Compact write log */ +static uint8_t eeprom_compact(void) { + /* Erase compacted pages and write log */ + eeprom_clear(); + + FLASH_Unlock(); + + FLASH_Status final_status = FLASH_COMPLETE; + + /* Write emulated eeprom contents from memory to compacted flash */ + uint16_t *src = (uint16_t *)DataBuf; + uintptr_t dest = FEE_COMPACTED_BASE_ADDRESS; + uint16_t value; + for (; dest < FEE_COMPACTED_LAST_ADDRESS; ++src, dest += 2) { + value = *src; + if (value) { + eeprom_printf("FLASH_ProgramHalfWord(0x%04lx, 0x%04x)\n", (uint32_t)dest, ~value); + FLASH_Status status = FLASH_ProgramHalfWord(dest, ~value); + if (status != FLASH_COMPLETE) final_status = status; + } + } + + FLASH_Lock(); + + if (debug_eeprom) { + println("eeprom_compacted:"); + print_eeprom(); + } + + return final_status; +} + +static uint8_t eeprom_write_direct_entry(uint16_t Address) { + /* Check if we can just write this directly to the compacted flash area */ + uintptr_t directAddress = FEE_COMPACTED_BASE_ADDRESS + (Address & 0xFFFE); + if (*(uint16_t *)directAddress == FEE_EMPTY_WORD) { + /* Write the value directly to the compacted area without a log entry */ + uint16_t value = ~*(uint16_t *)(&DataBuf[Address & 0xFFFE]); + /* Early exit if a write isn't needed */ + if (value == FEE_EMPTY_WORD) return FLASH_COMPLETE; + + FLASH_Unlock(); + + eeprom_printf("FLASH_ProgramHalfWord(0x%08lx, 0x%04x) [DIRECT]\n", (uint32_t)directAddress, value); + FLASH_Status status = FLASH_ProgramHalfWord(directAddress, value); + + FLASH_Lock(); + return status; + } + return 0; +} + +static uint8_t eeprom_write_log_word_entry(uint16_t Address) { + FLASH_Status final_status = FLASH_COMPLETE; + + uint16_t value = *(uint16_t *)(&DataBuf[Address]); + eeprom_printf("eeprom_write_log_word_entry(0x%04x): 0x%04x\n", Address, value); + + /* MSB signifies the lowest 128-byte optimization is not in effect */ + uint16_t encoding = FEE_WORD_ENCODING; + uint8_t entry_size; + if (value <= 1) { + encoding |= value << 13; + entry_size = 2; + } else { + encoding |= FEE_VALUE_NEXT; + entry_size = 4; + /* Writes to addresses less than 128 are byte log entries */ + Address -= FEE_BYTE_RANGE; + } + + /* if we can't find an empty spot, we must compact emulated eeprom */ + if (empty_slot > (uint16_t *)(FEE_WRITE_LOG_LAST_ADDRESS - entry_size)) { + /* compact the write log into the compacted flash area */ + return eeprom_compact(); + } + + /* Word log writes should be word-aligned. Take back a bit */ + Address >>= 1; + Address |= encoding; + + /* ok we found a place let's write our data */ + FLASH_Unlock(); + + /* address */ + eeprom_printf("FLASH_ProgramHalfWord(0x%08lx, 0x%04x)\n", (uint32_t)empty_slot, Address); + final_status = FLASH_ProgramHalfWord((uintptr_t)empty_slot++, Address); + + /* value */ + if (encoding == (FEE_WORD_ENCODING | FEE_VALUE_NEXT)) { + eeprom_printf("FLASH_ProgramHalfWord(0x%08lx, 0x%04x)\n", (uint32_t)empty_slot, ~value); + FLASH_Status status = FLASH_ProgramHalfWord((uintptr_t)empty_slot++, ~value); + if (status != FLASH_COMPLETE) final_status = status; + } + + FLASH_Lock(); + + return final_status; +} + +static uint8_t eeprom_write_log_byte_entry(uint16_t Address) { + eeprom_printf("eeprom_write_log_byte_entry(0x%04x): 0x%02x\n", Address, DataBuf[Address]); + + /* if couldn't find an empty spot, we must compact emulated eeprom */ + if (empty_slot >= (uint16_t *)FEE_WRITE_LOG_LAST_ADDRESS) { + /* compact the write log into the compacted flash area */ + return eeprom_compact(); + } + + /* ok we found a place let's write our data */ + FLASH_Unlock(); + + /* Pack address and value into the same word */ + uint16_t value = (Address << 8) | DataBuf[Address]; + + /* write to flash */ + eeprom_printf("FLASH_ProgramHalfWord(0x%08lx, 0x%04x)\n", (uint32_t)empty_slot, value); + FLASH_Status status = FLASH_ProgramHalfWord((uintptr_t)empty_slot++, value); + + FLASH_Lock(); + + return status; +} + +uint8_t EEPROM_WriteDataByte(uint16_t Address, uint8_t DataByte) { + /* if the address is out-of-bounds, do nothing */ + if (Address >= FEE_DENSITY_BYTES) { + eeprom_printf("EEPROM_WriteDataByte(0x%04x, 0x%02x) [BAD ADDRESS]\n", Address, DataByte); + return FLASH_BAD_ADDRESS; + } + + /* if the value is the same, don't bother writing it */ + if (DataBuf[Address] == DataByte) { + eeprom_printf("EEPROM_WriteDataByte(0x%04x, 0x%02x) [SKIP SAME]\n", Address, DataByte); + return 0; + } + + /* keep DataBuf cache in sync */ + DataBuf[Address] = DataByte; + eeprom_printf("EEPROM_WriteDataByte DataBuf[0x%04x] = 0x%02x\n", Address, DataBuf[Address]); + + /* perform the write into flash memory */ + /* First, attempt to write directly into the compacted flash area */ + FLASH_Status status = eeprom_write_direct_entry(Address); + if (!status) { + /* Otherwise append to the write log */ + if (Address < FEE_BYTE_RANGE) { + status = eeprom_write_log_byte_entry(Address); + } else { + status = eeprom_write_log_word_entry(Address & 0xFFFE); + } + } + if (status != 0 && status != FLASH_COMPLETE) { + eeprom_printf("EEPROM_WriteDataByte [STATUS == %d]\n", status); + } + return status; +} + +uint8_t EEPROM_WriteDataWord(uint16_t Address, uint16_t DataWord) { + /* if the address is out-of-bounds, do nothing */ + if (Address >= FEE_DENSITY_BYTES) { + eeprom_printf("EEPROM_WriteDataWord(0x%04x, 0x%04x) [BAD ADDRESS]\n", Address, DataWord); + return FLASH_BAD_ADDRESS; + } + + /* Check for word alignment */ + FLASH_Status final_status = FLASH_COMPLETE; + if (Address % 2) { + final_status = EEPROM_WriteDataByte(Address, DataWord); + FLASH_Status status = EEPROM_WriteDataByte(Address + 1, DataWord >> 8); + if (status != FLASH_COMPLETE) final_status = status; + if (final_status != 0 && final_status != FLASH_COMPLETE) { + eeprom_printf("EEPROM_WriteDataWord [STATUS == %d]\n", final_status); + } + return final_status; + } + + /* if the value is the same, don't bother writing it */ + uint16_t oldValue = *(uint16_t *)(&DataBuf[Address]); + if (oldValue == DataWord) { + eeprom_printf("EEPROM_WriteDataWord(0x%04x, 0x%04x) [SKIP SAME]\n", Address, DataWord); + return 0; + } + + /* keep DataBuf cache in sync */ + *(uint16_t *)(&DataBuf[Address]) = DataWord; + eeprom_printf("EEPROM_WriteDataWord DataBuf[0x%04x] = 0x%04x\n", Address, *(uint16_t *)(&DataBuf[Address])); + + /* perform the write into flash memory */ + /* First, attempt to write directly into the compacted flash area */ + final_status = eeprom_write_direct_entry(Address); + if (!final_status) { + /* Otherwise append to the write log */ + /* Check if we need to fall back to byte write */ + if (Address < FEE_BYTE_RANGE) { + final_status = FLASH_COMPLETE; + /* Only write a byte if it has changed */ + if ((uint8_t)oldValue != (uint8_t)DataWord) { + final_status = eeprom_write_log_byte_entry(Address); + } + FLASH_Status status = FLASH_COMPLETE; + /* Only write a byte if it has changed */ + if ((oldValue >> 8) != (DataWord >> 8)) { + status = eeprom_write_log_byte_entry(Address + 1); + } + if (status != FLASH_COMPLETE) final_status = status; + } else { + final_status = eeprom_write_log_word_entry(Address); + } + } + if (final_status != 0 && final_status != FLASH_COMPLETE) { + eeprom_printf("EEPROM_WriteDataWord [STATUS == %d]\n", final_status); + } + return final_status; +} + +uint8_t EEPROM_ReadDataByte(uint16_t Address) { + uint8_t DataByte = 0xFF; + + if (Address < FEE_DENSITY_BYTES) { + DataByte = DataBuf[Address]; + } + + eeprom_printf("EEPROM_ReadDataByte(0x%04x): 0x%02x\n", Address, DataByte); + + return DataByte; +} + +uint16_t EEPROM_ReadDataWord(uint16_t Address) { + uint16_t DataWord = 0xFFFF; + + if (Address < FEE_DENSITY_BYTES - 1) { + /* Check word alignment */ + if (Address % 2) { + DataWord = DataBuf[Address] | (DataBuf[Address + 1] << 8); + } else { + DataWord = *(uint16_t *)(&DataBuf[Address]); + } + } + + eeprom_printf("EEPROM_ReadDataWord(0x%04x): 0x%04x\n", Address, DataWord); + + return DataWord; +} + +/***************************************************************************** + * Bind to eeprom_driver.c + *******************************************************************************/ +void eeprom_driver_init(void) { + EEPROM_Init(); +} + +void eeprom_driver_erase(void) { + EEPROM_Erase(); +} + +void eeprom_read_block(void *buf, const void *addr, size_t len) { + const uint8_t *src = (const uint8_t *)addr; + uint8_t * dest = (uint8_t *)buf; + + /* Check word alignment */ + if (len && (uintptr_t)src % 2) { + /* Read the unaligned first byte */ + *dest++ = EEPROM_ReadDataByte((const uintptr_t)src++); + --len; + } + + uint16_t value; + bool aligned = ((uintptr_t)dest % 2 == 0); + while (len > 1) { + value = EEPROM_ReadDataWord((const uintptr_t)((uint16_t *)src)); + if (aligned) { + *(uint16_t *)dest = value; + dest += 2; + } else { + *dest++ = value; + *dest++ = value >> 8; + } + src += 2; + len -= 2; + } + if (len) { + *dest = EEPROM_ReadDataByte((const uintptr_t)src); + } +} + +void eeprom_write_block(const void *buf, void *addr, size_t len) { + uint8_t * dest = (uint8_t *)addr; + const uint8_t *src = (const uint8_t *)buf; + + /* Check word alignment */ + if (len && (uintptr_t)dest % 2) { + /* Write the unaligned first byte */ + EEPROM_WriteDataByte((uintptr_t)dest++, *src++); + --len; + } + + uint16_t value; + bool aligned = ((uintptr_t)src % 2 == 0); + while (len > 1) { + if (aligned) { + value = *(uint16_t *)src; + } else { + value = *(uint8_t *)src | (*(uint8_t *)(src + 1) << 8); + } + EEPROM_WriteDataWord((uintptr_t)((uint16_t *)dest), value); + dest += 2; + src += 2; + len -= 2; + } + + if (len) { + EEPROM_WriteDataByte((uintptr_t)dest, *src); + } +} |