fault_handler.c
/*
 * Copyright 2012-2022 Great Scott Gadgets <info@greatscottgadgets.com>
 * Copyright 2012 Jared Boone <jared@sharebrained.com>
 * Copyright 2013 Benjamin Vernoux <titanmkd@gmail.com>
 *
 * This file is part of HackRF.
 *
 * 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 2, 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; see the file COPYING.  If not, write to
 * the Free Software Foundation, Inc., 51 Franklin Street,
 * Boston, MA 02110-1301, USA.
 */

#include <stdint.h>

#include "fault_handler.h"

typedef struct {
	uint32_t r0;
	uint32_t r1;
	uint32_t r2;
	uint32_t r3;
	uint32_t r12;
	uint32_t lr;  /* Link Register. */
	uint32_t pc;  /* Program Counter. */
	uint32_t psr; /* Program Status Register. */
} hard_fault_stack_t;

__attribute__((naked)) void hard_fault_handler(void)
{
	__asm__("TST LR, #4");
	__asm__("ITE EQ");
	__asm__("MRSEQ R0, MSP");
	__asm__("MRSNE R0, PSP");
	__asm__("B hard_fault_handler_c");
}

volatile hard_fault_stack_t* hard_fault_stack_pt;

__attribute__((used)) void hard_fault_handler_c(uint32_t* args)
{
	/* hard_fault_stack_pt contains registers saved before the hard fault */
	hard_fault_stack_pt = (hard_fault_stack_t*) args;

	// args[0-7]: r0, r1, r2, r3, r12, lr, pc, psr
	// Other interesting registers to examine:
	//	CFSR: Configurable Fault Status Register
	//	HFSR: Hard Fault Status Register
	//	DFSR: Debug Fault Status Register
	//	AFSR: Auxiliary Fault Status Register
	//	MMAR: MemManage Fault Address Register
	//	BFAR: Bus Fault Address Register

	/*
	if( SCB->HFSR & SCB_HFSR_FORCED ) {	
		if( SCB->CFSR & SCB_CFSR_BFSR_BFARVALID ) {
			SCB->BFAR;
			if( SCB->CFSR & CSCB_CFSR_BFSR_PRECISERR ) {
			}
		}
	}
	*/
	while (1) {}
}

void mem_manage_handler()
{
	while (1) {}
}

void bus_fault_handler()
{
	while (1) {}
}

void usage_fault_handler()
{
	while (1) {}
}