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-rw-r--r--platforms/chibios/drivers/eeprom/eeprom_stm32.c629
-rw-r--r--platforms/chibios/drivers/eeprom/eeprom_stm32.h33
-rw-r--r--platforms/chibios/drivers/eeprom/eeprom_stm32_defs.h136
-rw-r--r--platforms/chibios/drivers/eeprom/eeprom_teensy.c546
-rwxr-xr-xplatforms/chibios/drivers/eeprom/eeprom_teensy.h25
5 files changed, 1369 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..a15bfe09ed
--- /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%04x;\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%04x;\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%04x)\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%08x\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%04x, 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%08x, 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%08x, 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%08x, 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%08x, 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);
+ }
+}
diff --git a/platforms/chibios/drivers/eeprom/eeprom_stm32.h b/platforms/chibios/drivers/eeprom/eeprom_stm32.h
new file mode 100644
index 0000000000..8fcfb556b8
--- /dev/null
+++ b/platforms/chibios/drivers/eeprom/eeprom_stm32.h
@@ -0,0 +1,33 @@
+/*
+ * 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
+ *
+ * This library assumes 8-bit data locations. To add a new MCU, please provide the flash
+ * page size and the total flash size in Kb. The number of available pages must be a multiple
+ * of 2. Only half of the pages account for the total EEPROM size.
+ * This library also assumes that the pages are not used by the firmware.
+ */
+
+#pragma once
+
+uint16_t EEPROM_Init(void);
+void EEPROM_Erase(void);
+uint8_t EEPROM_WriteDataByte(uint16_t Address, uint8_t DataByte);
+uint8_t EEPROM_WriteDataWord(uint16_t Address, uint16_t DataWord);
+uint8_t EEPROM_ReadDataByte(uint16_t Address);
+uint16_t EEPROM_ReadDataWord(uint16_t Address);
+
+void print_eeprom(void);
diff --git a/platforms/chibios/drivers/eeprom/eeprom_stm32_defs.h b/platforms/chibios/drivers/eeprom/eeprom_stm32_defs.h
new file mode 100644
index 0000000000..57d0440330
--- /dev/null
+++ b/platforms/chibios/drivers/eeprom/eeprom_stm32_defs.h
@@ -0,0 +1,136 @@
+/* Copyright 2021 QMK
+ *
+ * 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/>.
+ */
+#pragma once
+
+#include <hal.h>
+
+#if !defined(FEE_PAGE_SIZE) || !defined(FEE_PAGE_COUNT)
+# if defined(STM32F103xB) || defined(STM32F042x6) || defined(GD32VF103C8) || defined(GD32VF103CB)
+# ifndef FEE_PAGE_SIZE
+# define FEE_PAGE_SIZE 0x400 // Page size = 1KByte
+# endif
+# ifndef FEE_PAGE_COUNT
+# define FEE_PAGE_COUNT 2 // How many pages are used
+# endif
+# elif defined(STM32F103xE) || defined(STM32F303xC) || defined(STM32F303xE) || defined(STM32F072xB) || defined(STM32F070xB)
+# ifndef FEE_PAGE_SIZE
+# define FEE_PAGE_SIZE 0x800 // Page size = 2KByte
+# endif
+# ifndef FEE_PAGE_COUNT
+# define FEE_PAGE_COUNT 4 // How many pages are used
+# endif
+# elif defined(STM32F401xC) || defined(STM32F401xE) || defined(STM32F405xG) || defined(STM32F411xE)
+# ifndef FEE_PAGE_SIZE
+# define FEE_PAGE_SIZE 0x4000 // Page size = 16KByte
+# endif
+# ifndef FEE_PAGE_COUNT
+# define FEE_PAGE_COUNT 1 // How many pages are used
+# endif
+# endif
+#endif
+
+#if !defined(FEE_MCU_FLASH_SIZE)
+# if defined(STM32F042x6)
+# define FEE_MCU_FLASH_SIZE 32 // Size in Kb
+# elif defined(GD32VF103C8)
+# define FEE_MCU_FLASH_SIZE 64 // Size in Kb
+# elif defined(STM32F103xB) || defined(STM32F072xB) || defined(STM32F070xB) || defined(GD32VF103CB)
+# define FEE_MCU_FLASH_SIZE 128 // Size in Kb
+# elif defined(STM32F303xC) || defined(STM32F401xC)
+# define FEE_MCU_FLASH_SIZE 256 // Size in Kb
+# elif defined(STM32F103xE) || defined(STM32F303xE) || defined(STM32F401xE) || defined(STM32F411xE)
+# define FEE_MCU_FLASH_SIZE 512 // Size in Kb
+# elif defined(STM32F405xG)
+# define FEE_MCU_FLASH_SIZE 1024 // Size in Kb
+# endif
+#endif
+
+/* Start of the emulated eeprom */
+#if !defined(FEE_PAGE_BASE_ADDRESS)
+# if defined(STM32F401xC) || defined(STM32F401xE) || defined(STM32F405xG) || defined(STM32F411xE)
+# ifndef FEE_PAGE_BASE_ADDRESS
+# define FEE_PAGE_BASE_ADDRESS 0x08004000 // bodge to force 2nd 16k page
+# endif
+# else
+# ifndef FEE_FLASH_BASE
+# define FEE_FLASH_BASE 0x8000000
+# endif
+/* Default to end of flash */
+# define FEE_PAGE_BASE_ADDRESS ((uintptr_t)(FEE_FLASH_BASE) + FEE_MCU_FLASH_SIZE * 1024 - (FEE_PAGE_COUNT * FEE_PAGE_SIZE))
+# endif
+#endif
+
+/* Addressable range 16KByte: 0 <-> (0x1FFF << 1) */
+#define FEE_ADDRESS_MAX_SIZE 0x4000
+
+/* Size of combined compacted eeprom and write log pages */
+#define FEE_DENSITY_MAX_SIZE (FEE_PAGE_COUNT * FEE_PAGE_SIZE)
+
+#ifndef FEE_MCU_FLASH_SIZE_IGNORE_CHECK /* *TODO: Get rid of this check */
+# if FEE_DENSITY_MAX_SIZE > (FEE_MCU_FLASH_SIZE * 1024)
+# pragma message STR(FEE_DENSITY_MAX_SIZE) " > " STR(FEE_MCU_FLASH_SIZE * 1024)
+# error emulated eeprom: FEE_DENSITY_MAX_SIZE is greater than available flash size
+# endif
+#endif
+
+/* Size of emulated eeprom */
+#ifdef FEE_DENSITY_BYTES
+# if (FEE_DENSITY_BYTES > FEE_DENSITY_MAX_SIZE)
+# pragma message STR(FEE_DENSITY_BYTES) " > " STR(FEE_DENSITY_MAX_SIZE)
+# error emulated eeprom: FEE_DENSITY_BYTES exceeds FEE_DENSITY_MAX_SIZE
+# endif
+# if (FEE_DENSITY_BYTES == FEE_DENSITY_MAX_SIZE)
+# pragma message STR(FEE_DENSITY_BYTES) " == " STR(FEE_DENSITY_MAX_SIZE)
+# warning emulated eeprom: FEE_DENSITY_BYTES leaves no room for a write log. This will greatly increase the flash wear rate!
+# endif
+# if FEE_DENSITY_BYTES > FEE_ADDRESS_MAX_SIZE
+# pragma message STR(FEE_DENSITY_BYTES) " > " STR(FEE_ADDRESS_MAX_SIZE)
+# error emulated eeprom: FEE_DENSITY_BYTES is greater than FEE_ADDRESS_MAX_SIZE allows
+# endif
+# if ((FEE_DENSITY_BYTES) % 2) == 1
+# error emulated eeprom: FEE_DENSITY_BYTES must be even
+# endif
+#else
+/* Default to half of allocated space used for emulated eeprom, half for write log */
+# define FEE_DENSITY_BYTES (FEE_PAGE_COUNT * FEE_PAGE_SIZE / 2)
+#endif
+
+/* Size of write log */
+#ifdef FEE_WRITE_LOG_BYTES
+# if ((FEE_DENSITY_BYTES + FEE_WRITE_LOG_BYTES) > FEE_DENSITY_MAX_SIZE)
+# pragma message STR(FEE_DENSITY_BYTES) " + " STR(FEE_WRITE_LOG_BYTES) " > " STR(FEE_DENSITY_MAX_SIZE)
+# error emulated eeprom: FEE_WRITE_LOG_BYTES exceeds remaining FEE_DENSITY_MAX_SIZE
+# endif
+# if ((FEE_WRITE_LOG_BYTES) % 2) == 1
+# error emulated eeprom: FEE_WRITE_LOG_BYTES must be even
+# endif
+#else
+/* Default to use all remaining space */
+# define FEE_WRITE_LOG_BYTES (FEE_PAGE_COUNT * FEE_PAGE_SIZE - FEE_DENSITY_BYTES)
+#endif
+
+/* Start of the emulated eeprom compacted flash area */
+#define FEE_COMPACTED_BASE_ADDRESS FEE_PAGE_BASE_ADDRESS
+/* End of the emulated eeprom compacted flash area */
+#define FEE_COMPACTED_LAST_ADDRESS (FEE_COMPACTED_BASE_ADDRESS + FEE_DENSITY_BYTES)
+/* Start of the emulated eeprom write log */
+#define FEE_WRITE_LOG_BASE_ADDRESS FEE_COMPACTED_LAST_ADDRESS
+/* End of the emulated eeprom write log */
+#define FEE_WRITE_LOG_LAST_ADDRESS (FEE_WRITE_LOG_BASE_ADDRESS + FEE_WRITE_LOG_BYTES)
+
+#if defined(DYNAMIC_KEYMAP_EEPROM_MAX_ADDR) && (DYNAMIC_KEYMAP_EEPROM_MAX_ADDR >= FEE_DENSITY_BYTES)
+# error emulated eeprom: DYNAMIC_KEYMAP_EEPROM_MAX_ADDR is greater than the FEE_DENSITY_BYTES available
+#endif
diff --git a/platforms/chibios/drivers/eeprom/eeprom_teensy.c b/platforms/chibios/drivers/eeprom/eeprom_teensy.c
new file mode 100644
index 0000000000..c8777febde
--- /dev/null
+++ b/platforms/chibios/drivers/eeprom/eeprom_teensy.c
@@ -0,0 +1,546 @@
+#include <ch.h>
+#include <hal.h>
+
+#include "eeprom_teensy.h"
+#include "eeconfig.h"
+
+/*************************************/
+/* Hardware backend */
+/* */
+/* Code from PJRC/Teensyduino */
+/*************************************/
+
+/* Teensyduino Core Library
+ * http://www.pjrc.com/teensy/
+ * Copyright (c) 2013 PJRC.COM, LLC.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * 1. The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * 2. If the Software is incorporated into a build system that allows
+ * selection among a list of target devices, then similar target
+ * devices manufactured by PJRC.COM must be included in the list of
+ * target devices and selectable in the same manner.
+ *
+ * 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.
+ */
+
+#if defined(K20x) /* chip selection */
+/* Teensy 3.0, 3.1, 3.2; mchck; infinity keyboard */
+
+/*
+ ^^^ Here be dragons:
+ NXP AppNote AN4282 section 3.1 states that partitioning must only be done once.
+ Once EEPROM partitioning is done, the size is locked to this initial configuration.
+ Attempts to modify the EEPROM_SIZE setting may brick your board.
+*/
+
+// Writing unaligned 16 or 32 bit data is handled automatically when
+// this is defined, but at a cost of extra code size. Without this,
+// any unaligned write will cause a hard fault exception! If you're
+// absolutely sure all 16 and 32 bit writes will be aligned, you can
+// remove the extra unnecessary code.
+//
+# define HANDLE_UNALIGNED_WRITES
+
+// Minimum EEPROM Endurance
+// ------------------------
+# if (EEPROM_SIZE == 2048) // 35000 writes/byte or 70000 writes/word
+# define EEESIZE 0x33
+# elif (EEPROM_SIZE == 1024) // 75000 writes/byte or 150000 writes/word
+# define EEESIZE 0x34
+# elif (EEPROM_SIZE == 512) // 155000 writes/byte or 310000 writes/word
+# define EEESIZE 0x35
+# elif (EEPROM_SIZE == 256) // 315000 writes/byte or 630000 writes/word
+# define EEESIZE 0x36
+# elif (EEPROM_SIZE == 128) // 635000 writes/byte or 1270000 writes/word
+# define EEESIZE 0x37
+# elif (EEPROM_SIZE == 64) // 1275000 writes/byte or 2550000 writes/word
+# define EEESIZE 0x38
+# elif (EEPROM_SIZE == 32) // 2555000 writes/byte or 5110000 writes/word
+# define EEESIZE 0x39
+# endif
+
+/** \brief eeprom initialization
+ *
+ * FIXME: needs doc
+ */
+void eeprom_initialize(void) {
+ uint32_t count = 0;
+ uint16_t do_flash_cmd[] = {0xf06f, 0x037f, 0x7003, 0x7803, 0xf013, 0x0f80, 0xd0fb, 0x4770};
+ uint8_t status;
+
+ if (FTFL->FCNFG & FTFL_FCNFG_RAMRDY) {
+ // FlexRAM is configured as traditional RAM
+ // We need to reconfigure for EEPROM usage
+ FTFL->FCCOB0 = 0x80; // PGMPART = Program Partition Command
+ FTFL->FCCOB4 = EEESIZE; // EEPROM Size
+ FTFL->FCCOB5 = 0x03; // 0K for Dataflash, 32K for EEPROM backup
+ __disable_irq();
+ // do_flash_cmd() must execute from RAM. Luckily the C syntax is simple...
+ (*((void (*)(volatile uint8_t *))((uint32_t)do_flash_cmd | 1)))(&(FTFL->FSTAT));
+ __enable_irq();
+ status = FTFL->FSTAT;
+ if (status & (FTFL_FSTAT_RDCOLERR | FTFL_FSTAT_ACCERR | FTFL_FSTAT_FPVIOL)) {
+ FTFL->FSTAT = (status & (FTFL_FSTAT_RDCOLERR | FTFL_FSTAT_ACCERR | FTFL_FSTAT_FPVIOL));
+ return; // error
+ }
+ }
+ // wait for eeprom to become ready (is this really necessary?)
+ while (!(FTFL->FCNFG & FTFL_FCNFG_EEERDY)) {
+ if (++count > 20000) break;
+ }
+}
+
+# define FlexRAM ((uint8_t *)0x14000000)
+
+/** \brief eeprom read byte
+ *
+ * FIXME: needs doc
+ */
+uint8_t eeprom_read_byte(const uint8_t *addr) {
+ uint32_t offset = (uint32_t)addr;
+ if (offset >= EEPROM_SIZE)