1 files changed, 144 insertions, 0 deletions
diff --git a/cm3cpp/flash_otp.hpp b/cm3cpp/flash_otp.hpp
new file mode 100644
index 0000000..159d072
--- /dev/null
+++ b/cm3cpp/flash_otp.hpp
@@ -0,0 +1,144 @@
+#ifndef CM3CPP_FLASH_OTP_HPP_
+#define CM3CPP_FLASH_OTP_HPP_
+
+#include <libopencm3/stm32/flash.h>
+#include <libopencmsis/core_cm3.h>
+
+namespace cm3cpp {
+
+namespace flash {
+
+enum class OtpBlock : uint8_t
+{
+    BLOCK_0,
+    BLOCK_1,
+    BLOCK_2,
+    BLOCK_3,
+    BLOCK_4,
+    BLOCK_5,
+    BLOCK_6,
+    BLOCK_7,
+    BLOCK_8,
+    BLOCK_9,
+    BLOCK_10,
+    BLOCK_11,
+    BLOCK_12,
+    BLOCK_13,
+    BLOCK_14,
+    BLOCK_15,
+};
+
+enum class OtpByte
+{
+    BYTE_0,
+    BYTE_1,
+    BYTE_2,
+    BYTE_3,
+    BYTE_4,
+    BYTE_5,
+    BYTE_6,
+    BYTE_7,
+    BYTE_8,
+    BYTE_9,
+    BYTE_10,
+    BYTE_11,
+    BYTE_12,
+    BYTE_13,
+    BYTE_14,
+    BYTE_15,
+    BYTE_16,
+    BYTE_17,
+    BYTE_18,
+    BYTE_19,
+    BYTE_20,
+    BYTE_21,
+    BYTE_22,
+    BYTE_23,
+    BYTE_24,
+    BYTE_25,
+    BYTE_26,
+    BYTE_27,
+    BYTE_28,
+    BYTE_29,
+    BYTE_30,
+    BYTE_31,
+};
+
+enum class Flag
+{
+    BSY = FLASH_SR_BSY,
+    PGSERR = FLASH_SR_PGSERR,
+    PGPERR = FLASH_SR_PGPERR,
+    PGAERR = FLASH_SR_PGAERR,
+    WRPERR = FLASH_SR_WRPERR,
+    OPERR = FLASH_SR_OPERR,
+    EOP = FLASH_SR_EOP,
+};
+
+class FlashOtp
+{
+ public:
+    static void write(OtpBlock block, OtpByte byte, uint8_t data)
+    {
+        flash_unlock();
+        clear_flag(Flag::EOP);
+        clear_flag(Flag::OPERR);
+        clear_flag(Flag::WRPERR);
+        clear_flag(Flag::PGAERR);
+        clear_flag(Flag::PGPERR);
+        clear_flag(Flag::PGSERR);
+        flash_wait_for_last_operation();
+        uint32_t address = _OTP_START_ADDR +
+                           ((uint32_t)block * _OTP_BYTES_IN_BLOCK) +
+                           (uint32_t)byte;
+        __disable_irq();
+        flash_program_byte(address, data);
+        __enable_irq();
+        flash_lock();
+    }
+
+    static uint8_t read(OtpBlock block, OtpByte byte)
+    {
+        uint32_t address = _OTP_START_ADDR +
+                           ((uint32_t)block * _OTP_BYTES_IN_BLOCK) +
+                           (uint32_t)byte;
+        return *(uint8_t*)address;
+    }
+
+    static const uint8_t* const get_pointer(OtpBlock block, OtpByte byte)
+    {
+        uint32_t address = _OTP_START_ADDR +
+                           ((uint32_t)block * _OTP_BYTES_IN_BLOCK) +
+                           (uint32_t)byte;
+        return (uint8_t*)address;
+    }
+
+    static bool get_flag(Flag flag)
+    {
+        uint32_t status = FLASH_SR | (uint32_t)flag;
+        if (status > 0)
+            return true;
+        return false;
+    }
+
+    static void clear_flag(Flag flag)
+    {
+        if (flag == Flag::BSY)
+            return;
+
+        FLASH_SR |= (uint32_t)flag;
+    }
+
+ private:
+    static constexpr uint32_t _OTP_START_ADDR = (0x1FFF7800);
+    static constexpr uint32_t _OTP_LOCK_ADDR = (0x1FFF7A00);
+    static constexpr uint32_t _OTP_BLOCKS = 16;
+    static constexpr uint32_t _OTP_BYTES_IN_BLOCK = 32;
+    static constexpr uint32_t _OTP_SIZE = (_OTP_BLOCKS * _OTP_BYTES_IN_BLOCK);
+};
+
+} /* namespace flash */
+
+} /* namespace cm3cpp */
+
+#endif /* CM3CPP_FLASH_OTP_HPP_ */