qmk-firmware/platforms/chibios/drivers/eeprom/eeprom_stm32.c
2022-08-04 22:15:42 +10:00

630 lines
22 KiB
C

/*
* 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);
}
}