/*
 * This file is part of the Black Magic Debug project.
 *
 * Copyright (C) 2015  Black Sphere Technologies Ltd.
 * Written by Gareth McMullin <gareth@blacksphere.co.nz>
 *
 * 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/>.
 */
#include "general.h"
#include <libopencm3/stm32/desig.h>

char *serial_no_read(char *s)
{
#if DFU_SERIAL_LENGTH == 9
	int i;
	volatile uint32_t *unique_id_p = (volatile uint32_t *)DESIG_UNIQUE_ID_BASE;
	uint32_t unique_id = *unique_id_p +
			*(unique_id_p + 1) +
			*(unique_id_p + 2);
	/* Fetch serial number from chip's unique ID */
	for(i = 0; i < 8; i++) {
		s[7-i] = ((unique_id >> (4*i)) & 0xF) + '0';
	}
	for(i = 0; i < 8; i++)
		if(s[i] > '9')
			s[i] += 'A' - '9' - 1;
#elif DFU_SERIAL_LENGTH == 13
	/* Use the same serial number as the ST DFU Bootloader.*/
	uint16_t *uid = (uint16_t *)DESIG_UNIQUE_ID_BASE;
# if defined(STM32F4) || defined(STM32F7)
	int offset = 3;
# elif defined(STM32L0) ||  defined(STM32F0) || defined(STM32F3)
	int offset = 5;
# endif
	sprintf(s, "%04X%04X%04X",
            uid[1] + uid[5], uid[0] + uid[4], uid[offset]);
#elif DFU_SERIAL_LENGTH == 25
	int i;
	uint32_t unique_id[3];
	memcpy(unique_id, (uint32_t *)DESIG_UNIQUE_ID_BASE, 12);
	for(i = 0; i < 8; i++) {
		s[ 7-i] = ((unique_id[0] >> (4*i)) & 0xF) + '0';
		s[15-i] = ((unique_id[1] >> (4*i)) & 0xF) + '0';
		s[23-i] = ((unique_id[2] >> (4*i)) & 0xF) + '0';
	}
	for (i = 0; i < 24; i++)
		if(s[i] > '9')
			s[i] += 'A' - '9' - 1;
#else
# WARNING "Unhandled DFU_SERIAL_LENGTH"
#endif
	s[DFU_SERIAL_LENGTH - 1] = 0;
	return s;
}