[l1-flash/eeprom] Add lock/unlock/eeprom helper routines

2 files changed, 97 insertions, 2 deletions

diff --git a/include/libopencm3/stm32/l1/flash.h b/include/libopencm3/stm32/l1/flash.h
index a0c7a66e..680de5cc 100644
--- a/include/libopencm3/stm32/l1/flash.h
+++ b/include/libopencm3/stm32/l1/flash.h
@@ -138,6 +138,17 @@ void flash_64bit_disable(void);
 void flash_prefetch_enable(void);
 void flash_prefetch_disable(void);
 void flash_set_ws(uint32_t ws);
+void flash_unlock_pecr(void);
+void flash_lock_pecr(void);
+void flash_unlock_progmem(void);
+void flash_lock_progmem(void);
+void flash_unlock_option_bytes(void);
+void flash_lock_option_bytes(void);
+void flash_unlock(void);
+void flash_lock(void);
+
+void eeprom_program_word(uint32_t address, uint32_t data);
+void eeprom_program_words(uint32_t address, uint32_t *data, int length_in_words);
 
 END_DECLS
 /**@}*/
diff --git a/lib/stm32/l1/flash.c b/lib/stm32/l1/flash.c
index dc568654..fdd2cca3 100644
--- a/lib/stm32/l1/flash.c
+++ b/lib/stm32/l1/flash.c
@@ -29,7 +29,7 @@
  *
  * Copyright (C) 2010 Thomas Otto <tommi@viadmin.org>
  * Copyright (C) 2010 Mark Butler <mbutler@physics.otago.ac.nz>
- * Copyright (C) 2012 Karl Palsson <karlp@tweak.net.au>
+ * Copyright (C) 2012-13 Karl Palsson <karlp@tweak.net.au>
  *
  * This library is free software: you can redistribute it and/or modify
  * it under the terms of the GNU Lesser General Public License as published by
@@ -120,5 +120,89 @@ void flash_set_ws(uint32_t ws)
 	reg32 |= ws;
 	FLASH_ACR = reg32;
 }
-/**@}*/
 
+void flash_unlock_pecr(void) {
+	FLASH_PEKEYR = FLASH_PEKEYR_PEKEY1;
+	FLASH_PEKEYR = FLASH_PEKEYR_PEKEY2;
+}
+
+void flash_lock_pecr(void) {
+	FLASH_PECR |= FLASH_PECR_PELOCK;
+}
+
+void flash_unlock_progmem(void) {
+	flash_unlock_pecr();
+	FLASH_PRGKEYR = FLASH_PRGKEYR_PRGKEY1;
+	FLASH_PRGKEYR = FLASH_PRGKEYR_PRGKEY2;
+}
+
+void flash_lock_progmem(void) {
+	FLASH_PECR |= FLASH_PECR_PRGLOCK;
+}
+
+void flash_unlock_option_bytes(void) {
+	flash_unlock_pecr();
+	FLASH_OPTKEYR = FLASH_OPTKEYR_OPTKEY1;
+	FLASH_OPTKEYR = FLASH_OPTKEYR_OPTKEY2;
+}
+
+void flash_lock_option_bytes(void) {
+	FLASH_PECR |= FLASH_PECR_OPTLOCK;
+}
+
+/** @brief Unlock all segments of flash
+ *
+ */
+void flash_unlock(void) {
+	flash_unlock_pecr();
+	flash_unlock_progmem();
+	flash_unlock_option_bytes();
+}
+
+/** @brief Lock all segments of flash
+ *
+ */
+void flash_lock(void) {
+	flash_lock_option_bytes();
+	flash_lock_progmem();
+	flash_lock_pecr();
+}
+
+/** @brief Write a word to eeprom
+ *
+ * @param address assumed to be in the eeprom space, no checking
+ * @param data word to write
+ */
+void eeprom_program_word(uint32_t address, uint32_t data) {
+	flash_unlock_pecr();
+	/* erase only if needed */
+	FLASH_PECR &= ~FLASH_PECR_FTDW;
+	MMIO32(address) = data;
+	flash_lock_pecr();
+}
+
+/** @brief Write a block of words to eeprom
+ *
+ * Writes a block of words to EEPROM at the requested address, erasing if necessary,
+ * and locking afterwards.  Only wordwise writing is safe for writing any value
+ *
+ * @param[in] address must point to EEPROM space, no checking!
+ * @param[in] data pointer to data to write
+ * @param[in] length size of of data in WORDS!
+ *  */
+void eeprom_program_words(uint32_t address, uint32_t *data, int length_in_words)
+{
+       int i;
+       flash_unlock_pecr();
+       while (FLASH_SR & FLASH_SR_BSY);
+       /* erase only if needed */
+       FLASH_PECR &= ~FLASH_PECR_FTDW;
+       for (i = 0; i < length_in_words; i++) {
+               MMIO32(address + (i * sizeof(uint32_t))) = *(data+i);
+               while (FLASH_SR & FLASH_SR_BSY);
+       }
+       flash_lock_pecr();
+}
+
+
+/**@}*/