--- /dev/null
+// Copyright (C) 2020 Michael McMaster <michael@codesrc.com>
+//
+// This file is part of SCSI2SD.
+//
+// SCSI2SD 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.
+//
+// SCSI2SD 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 SCSI2SD. If not, see <http://www.gnu.org/licenses/>.
+
+#include "hwversion.h"
+#include "stm32f2xx.h"
+#include "config.h"
+#include "time.h"
+
+// Store hardware version details to the "One Time Programmable" flash memory
+// This is 512 bytes that can only be written to ONCE and once only.
+// It can be read by dfu-util, so once we write the marker it can be
+// detected even when the firmware isn't running.
+
+// Values for STM32F401RE
+const size_t OTP_SIZE = 512;
+const size_t OTP_BLOCKS = 16;
+const size_t OTP_BLOCK_SIZE = OTP_SIZE / OTP_BLOCKS;
+
+const size_t OTP_BLOCK_NUM = 0;
+
+// Define some pointers for writing, but also to allow easy reading back values
+#define FLASH_OTP_BASE 0x1FFF7800
+const uint8_t *otp = (uint8_t*)(FLASH_OTP_BASE + OTP_BLOCK_NUM * OTP_BLOCK_SIZE);
+const uint32_t *otp32 = (uint32_t*)(FLASH_OTP_BASE + OTP_BLOCK_NUM * OTP_BLOCK_SIZE);
+const uint8_t *lock = (uint8_t*)(FLASH_OTP_BASE + OTP_SIZE + OTP_BLOCK_NUM);
+
+const uint32_t marker = 0x06002020;
+
+static void
+checkHwSensePins()
+{
+ // Check the board version is correct.
+ // Sense pins are configued as pullup, and connected to GND for 2020 hw,
+ // or N/C for v6 ref F or older
+ if (HAL_GPIO_ReadPin(VER_ID1_GPIO_Port, VER_ID1_Pin) ||
+ HAL_GPIO_ReadPin(VER_ID2_GPIO_Port, VER_ID2_Pin))
+ {
+ // Oh dear, wrong version. Do not pass go.
+ while (1) {}
+ }
+}
+
+void
+s2s_checkHwVersion()
+{
+ checkHwSensePins();
+
+ // Write a marker to flash that can be read by dfu-util now that we know
+ // the version is correct.
+ if (*otp32 != marker)
+ {
+ // Double-check the pins are good.
+ s2s_delay_ms(10);
+ checkHwSensePins();
+
+ // Well, pins are good. Make sure marker isn't set at all
+ if (*otp32 != 0xffffffff)
+ {
+ // Some other version was set.
+ while (1) {}
+ }
+
+ // Write the marker to flash.
+ if (HAL_FLASH_Unlock() != HAL_OK)
+ {
+ return;
+ }
+
+ // Write 4 bytes to the start of OTP.
+ if (HAL_FLASH_Program(
+ FLASH_TYPEPROGRAM_WORD,
+ (uint32_t)otp,
+ marker) != HAL_OK)
+ {
+ HAL_FLASH_Lock();
+ return;
+ }
+
+ // Lock OTP page
+ if (HAL_FLASH_Program(FLASH_TYPEPROGRAM_BYTE, (uint32_t)lock, 0x00)) {
+ HAL_FLASH_Lock();
+ return;
+ }
+
+ HAL_FLASH_Lock();
+ }
+}
+
--- /dev/null
+// Copyright (C) 2020 Michael McMaster <michael@codesrc.com>
+//
+// This file is part of SCSI2SD.
+//
+// SCSI2SD 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.
+//
+// SCSI2SD 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 SCSI2SD. If not, see <http://www.gnu.org/licenses/>.
+
+#ifndef S2S_HWVERSION_H
+#define S2S_HWVERSION_H
+
+void s2s_checkHwVersion(void);
+
+#endif