path: root/src/target/arm9tdmi.c

/***************************************************************************
 *   Copyright (C) 2005 by Dominic Rath                                    *
 *   Dominic.Rath@gmx.de                                                   *
 *                                                                         *
 *   Copyright (C) 2008 by Spencer Oliver                                  *
 *   spen@spen-soft.co.uk                                                  *
 *                                                                         *
 *   Copyright (C) 2008 by Hongtao Zheng                                   *
 *   hontor@126.com                                                        *
 *                                                                         *
 *   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 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, write to the                         *
 *   Free Software Foundation, Inc.,                                       *
 *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
 ***************************************************************************/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include "arm9tdmi.h"
#include "target_type.h"
#include "register.h"
#include "arm_opcodes.h"


/*
 * NOTE:  this holds code that's used with multiple ARM9 processors:
 *  - ARM9TDMI (ARMv4T) ... in ARM920, ARM922, and ARM940 cores
 *  - ARM9E-S (ARMv5TE) ... in ARM946, ARM966, and ARM968 cores
 *  - ARM9EJS (ARMv5TEJ) ... in ARM926 core
 *
 * In short, the file name is a misnomer ... it is NOT specific to
 * that first generation ARM9 processor, or cores using it.
 */

#if 0
#define _DEBUG_INSTRUCTION_EXECUTION_
#endif

enum arm9tdmi_vector_bit
{
	ARM9TDMI_RESET_VECTOR = 0x01,
	ARM9TDMI_UNDEF_VECTOR = 0x02,
	ARM9TDMI_SWI_VECTOR = 0x04,
	ARM9TDMI_PABT_VECTOR = 0x08,
	ARM9TDMI_DABT_VECTOR = 0x10,
	/* BIT(5) reserved -- must be zero */
	ARM9TDMI_IRQ_VECTOR = 0x40,
	ARM9TDMI_FIQ_VECTOR = 0x80,
};

static const struct arm9tdmi_vector {
	const char *name;
	uint32_t value;
} arm9tdmi_vectors[] = {
	{"reset", ARM9TDMI_RESET_VECTOR},
	{"undef", ARM9TDMI_UNDEF_VECTOR},
	{"swi", ARM9TDMI_SWI_VECTOR},
	{"pabt", ARM9TDMI_PABT_VECTOR},
	{"dabt", ARM9TDMI_DABT_VECTOR},
	{"irq", ARM9TDMI_IRQ_VECTOR},
	{"fiq", ARM9TDMI_FIQ_VECTOR},
	{0, 0},
};

int arm9tdmi_examine_debug_reason(struct target *target)
{
	int retval = ERROR_OK;
	struct arm7_9_common *arm7_9 = target_to_arm7_9(target);

	/* only check the debug reason if we don't know it already */
	if ((target->debug_reason != DBG_REASON_DBGRQ)
			&& (target->debug_reason != DBG_REASON_SINGLESTEP))
	{
		struct scan_field fields[3];
		uint8_t databus[4];
		uint8_t instructionbus[4];
		uint8_t debug_reason;

		fields[0].num_bits = 32;
		fields[0].out_value = NULL;
		fields[0].in_value = databus;

		fields[1].num_bits = 3;
		fields[1].out_value = NULL;
		fields[1].in_value = &debug_reason;

		fields[2].num_bits = 32;
		fields[2].out_value = NULL;
		fields[2].in_value = instructionbus;

		if ((retval = arm_jtag_scann(&arm7_9->jtag_info, 0x1, TAP_DRPAUSE)) != ERROR_OK)
		{
			return retval;
		}
		retval = arm_jtag_set_instr(&arm7_9->jtag_info, arm7_9->jtag_info.intest_instr, NULL, TAP_DRPAUSE);
		if (retval != ERROR_OK)
			return retval;

		jtag_add_dr_scan(arm7_9->jtag_info.tap, 3, fields, TAP_DRPAUSE);
		if ((retval = jtag_execute_queue()) != ERROR_OK)
		{
			return retval;
		}

		fields[0].in_value = NULL;
		fields[0].out_value = databus;
		fields[1].in_value = NULL;
		fields[1].out_value = &debug_reason;
		fields[2].in_value = NULL;
		fields[2].out_value = instructionbus;

		jtag_add_dr_scan(arm7_9->jtag_info.tap, 3, fields, TAP_DRPAUSE);

		if (debug_reason & 0x4)
			if (debug_reason & 0x2)
				target->debug_reason = DBG_REASON_WPTANDBKPT;
		else
			target->debug_reason = DBG_REASON_WATCHPOINT;
		else
			target->debug_reason = DBG_REASON_BREAKPOINT;
	}

	return ERROR_OK;
}

/* put an instruction in the ARM9TDMI pipeline or write the data bus,
 * and optionally read data
 */
int arm9tdmi_clock_out(struct arm_jtag *jtag_info, uint32_t instr,
		uint32_t out, uint32_t *in, int sysspeed)
{
	int retval = ERROR_OK;
	struct scan_field fields[3];
	uint8_t out_buf[4];
	uint8_t instr_buf[4];
	uint8_t sysspeed_buf = 0x0;

	/* prepare buffer */
	buf_set_u32(out_buf, 0, 32, out);

	buf_set_u32(instr_buf, 0, 32, flip_u32(instr, 32));

	if (sysspeed)
		buf_set_u32(&sysspeed_buf, 2, 1, 1);

	if ((retval = arm_jtag_scann(jtag_info, 0x1, TAP_DRPAUSE)) != ERROR_OK)
	{
		return retval;
	}

	retval = arm_jtag_set_instr(jtag_info, jtag_info->intest_instr,