From d78273a5aa37b2c3c3eafa2d0667ffa58bb91aed Mon Sep 17 00:00:00 2001
From: Samuel Sadok <samuel.sadok@bluewin.ch>
Date: Tue, 27 Mar 2018 19:54:02 -0700
Subject: [PATCH] add write_otp to Makefile

---
 Firmware/Makefile | 44 ++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 44 insertions(+)

diff --git a/Firmware/Makefile b/Firmware/Makefile
index 84a28e30..dcfd74ae 100644
--- a/Firmware/Makefile
+++ b/Firmware/Makefile
@@ -28,6 +28,50 @@ bmp: all
 erase_config:
 	openocd -f interface/stlink-v2.cfg -f target/stm32f4x.cfg -c init -c reset\ halt -c flash\ erase_address\ 0x80C0000\ 0x40000 -c reset\ run -c exit
 
+# OTP format:
+#  - OTP format version (0xFE: version 1)
+#  - vendor ID (01: ODrive Robotics - do not use this on custom incompatible hardware!)
+#  - product ID (01: ODrive)
+#  - hardware major version
+#  - hardware minor version
+#  - hardware variant (00: 24V, 01: 48V)
+# Bits in the OTP can only ever be set to 0 but never back to 1.
+# Therefore do not try to run this on the same board twice with different data.
+#
+# This OpenOCD command is intended for a STM32F405 and does the following:
+#  FLASH_KEYR = 0x45670123; // unlock FLASH_CR
+#  FLASH_KEYR = 0xCDEF89AB; // unlock FLASH_CR
+#  FLASH_CR = (1 << FLASH_CR_PG); // unlock flash memory
+#  [write OTP]
+write_otp:
+ifeq ($(ODRV_FACTORY),TRUE)
+	# Data: 
+	openocd -f interface/stlink-v2.cfg -f target/stm32f4x.cfg \
+		-c init \
+		-c 'reset halt' \
+		-c 'mww 0x40023C04 0x45670123' \
+		-c 'mww 0x40023C04 0xCDEF89AB' \
+		-c 'mww 0x40023C10 0x00000001' -c 'sleep 10' \
+		-c 'mwb 0x1fff7800 0xFE' -c 'sleep 10' \
+		-c 'mwb 0x1fff7801 0x01' -c 'sleep 10' \
+		-c 'mwb 0x1fff7802 0x01' -c 'sleep 10' \
+		-c 'mwb 0x1fff7803 0x03' -c 'sleep 10' \
+		-c 'mwb 0x1fff7804 0x04' -c 'sleep 10' \
+		-c 'mwb 0x1fff7805 0x01' -c 'sleep 10' \
+		-c 'reset run' \
+		-c exit
+
+else
+	@echo "The one-time programmable memory can only be"
+	@echo "written ONCE on every board (what a surprise)."
+	@echo "If you're on an ODrive v3.5 or later we already did this for you."
+	@echo "Otherwise, if you're mentally ready for this, do the following steps:"
+	@echo " 1. open the Makefile and look at the write_otp target"
+	@echo " 2. understand the structure of the OTP"
+	@echo " 3. edit the bytes that are written to match your board version"
+	@echo "Run this command again, this time with ODRV_FACTORY=TRUE"
+endif
+
 clean:
 	-rm -fR .dep $(BUILD_DIR)