riscv-openocd/src/target/mips32_pracc.c

/***************************************************************************
 *   Copyright (C) 2008 by Spencer Oliver                                  *
 *   spen@spen-soft.co.uk                                                  *
 *                                                                         *
 *   Copyright (C) 2008 by David T.L. Wong                                 *
 *                                                                         *
 *   Copyright (C) 2009 by David N. Claffey <dnclaffey@gmail.com>          *
 *                                                                         *
 *   Copyright (C) 2011 by Drasko DRASKOVIC                                *
 *   drasko.draskovic@gmail.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.             *
 ***************************************************************************/

/*
 * This version has optimized assembly routines for 32 bit operations:
 * - read word
 * - write word
 * - write array of words
 *
 * One thing to be aware of is that the MIPS32 cpu will execute the
 * instruction after a branch instruction (one delay slot).
 *
 * For example:
 *  LW $2, ($5 +10)
 *  B foo
 *  LW $1, ($2 +100)
 *
 * The LW $1, ($2 +100) instruction is also executed. If this is
 * not wanted a NOP can be inserted:
 *
 *  LW $2, ($5 +10)
 *  B foo
 *  NOP
 *  LW $1, ($2 +100)
 *
 * or the code can be changed to:
 *
 *  B foo
 *  LW $2, ($5 +10)
 *  LW $1, ($2 +100)
 *
 * The original code contained NOPs. I have removed these and moved
 * the branches.
 *
 * I also moved the PRACC_STACK to 0xFF204000. This allows
 * the use of 16 bits offsets to get pointers to the input
 * and output area relative to the stack. Note that the stack
 * isn't really a stack (the stack pointer is not 'moving')
 * but a FIFO simulated in software.
 *
 * These changes result in a 35% speed increase when programming an
 * external flash.
 *
 * More improvement could be gained if the registers do no need
 * to be preserved but in that case the routines should be aware
 * OpenOCD is used as a flash programmer or as a debug tool.
 *
 * Nico Coesel
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <helper/time_support.h>

#include "mips32.h"
#include "mips32_pracc.h"

struct mips32_pracc_context {
	uint32_t *local_iparam;
	int num_iparam;
	uint32_t *local_oparam;
	int num_oparam;
	const uint32_t *code;
	int code_len;
	uint32_t stack[32];
	int stack_offset;
	struct mips_ejtag *ejtag_info;
};

static int mips32_pracc_read_mem8(struct mips_ejtag *ejtag_info,
		uint32_t addr, int count, uint8_t *buf);
static int mips32_pracc_read_mem16(struct mips_ejtag *ejtag_info,
		uint32_t addr, int count, uint16_t *buf);
static int mips32_pracc_read_mem32(struct mips_ejtag *ejtag_info,
		uint32_t addr, int count, uint32_t *buf);
static int mips32_pracc_read_u32(struct mips_ejtag *ejtag_info,
		uint32_t addr, uint32_t *buf);

static int mips32_pracc_write_mem8(struct mips_ejtag *ejtag_info,
		uint32_t addr, int count, uint8_t *buf);
static int mips32_pracc_write_mem16(struct mips_ejtag *ejtag_info,
		uint32_t addr, int count, uint16_t *buf);
static int mips32_pracc_write_mem32(struct mips_ejtag *ejtag_info,
		uint32_t addr, int count, uint32_t *buf);
static int mips32_pracc_write_u32(struct mips_ejtag *ejtag_info,
		uint32_t addr, uint32_t *buf);

static int mips32_pracc_sync_cache(struct mips_ejtag *ejtag_info,
		uint32_t start_addr, uint32_t end_addr);
static int mips32_pracc_clean_invalidate_cache(struct mips_ejtag *ejtag_info,
		uint32_t start_addr, uint32_t end_addr);

static int wait_for_pracc_rw(struct mips_ejtag *ejtag_info, uint32_t *ctrl)
{
	uint32_t ejtag_ctrl;
	long long then = timeval_ms();
	int timeout;
	int retval;

	/* wait for the PrAcc to become "1" */
	mips_ejtag_set_instr(ejtag_info, EJTAG_INST_CONTROL);
	ejtag_ctrl = ejtag_info->ejtag_ctrl;

	while (1) {
		retval = mips_ejtag_drscan_32(ejtag_info, &ejtag_ctrl);
		if (retval != ERROR_OK)
			return retval;

		if (ejtag_ctrl & EJTAG_CTRL_PRACC)
			break;

		timeout = timeval_ms() - then;
		if (timeout > 1000) {
			LOG_DEBUG("DEBUGMODULE: No memory access in progress!");
			return ERROR_JTAG_DEVICE_ERROR;
		}
	}

	*ctrl = ejtag_ctrl;
	return ERROR_OK;
}

static int mips32_pracc_exec_read(struct mips32_pracc_context *ctx, uint32_t address)
{
	struct mips_ejtag *ejtag_info = ctx->ejtag_info;
	int offset;
	uint32_t ejtag_ctrl, data;

	if ((address >= MIPS32_PRACC_PARAM_IN)
		&& (address <= MIPS32_PRACC_PARAM_IN + ctx->num_iparam * 4)) {
		offset = (address - MIPS32_PRACC_PARAM_IN) / 4;
		data = ctx->local_iparam[offset];
	} else if ((address >= MIPS32_PRACC_PARAM_OUT)
		&& (address <= MIPS32_PRACC_PARAM_OUT + ctx->num_oparam * 4)) {
		offset = (address - MIPS32_PRACC_PARAM_OUT) / 4;
		data = ctx->local_oparam[offset];
	} else if ((address >= MIPS32_PRACC_TEXT)
		&& (address <= MIPS32_PRACC_TEXT + ctx->code_len * 4)) {
		offset = (address - MIPS32_PRACC_TEXT) / 4;
		data = ctx->code[offset];
	} else if (address == MIPS32_PRACC_STACK) {
		/* save to our debug stack */
		data = ctx->stack[--ctx->stack_offset];
	} else {
		/* TODO: send JMP 0xFF200000 instruction. Hopefully processor jump back
		 * to start of debug vector */

		LOG_ERROR("Error reading unexpected address 0x%8.8" PRIx32 "", address);
		return ERROR_JTAG_DEVICE_ERROR;
	}

	/* Send the data out */
	mips_ejtag_set_instr(ctx->ejtag_info, EJTAG_INST_DATA);
	mips_ejtag_drscan_32_out(ctx->ejtag_info, data);

	/* Clear the access pending bit (let the processor eat!) */
	ejtag_ctrl = ejtag_info->ejtag_ctrl & ~EJTAG_CTRL_PRACC;
	mips_ejtag_set_instr(ctx->ejtag_info, EJTAG_INST_CONTROL);
	mips_ejtag_drscan_32_out(ctx->ejtag_info, ejtag_ctrl);

	return jtag_execute_queue();
}

static int mips32_pracc_exec_write(struct mips32_pracc_context *ctx, uint32_t address)
{
	uint32_t ejtag_ctrl, data;
	int offset;
	struct mips_ejtag *ejtag_info = ctx->ejtag_info;
	int retval;

	mips_ejtag_set_instr(ctx->ejtag_info, EJTAG_INST_DATA);
	retval = mips_ejtag_drscan_32(ctx->ejtag_info, &data);
	if (retval != ERROR_OK)
		return retval;

	/* Clear access pending bit */
	ejtag_ctrl = ejtag_info->ejtag_ctrl & ~EJTAG_CTRL_PRACC;
	mips_ejtag_set_instr(ctx->ejtag_info, EJTAG_INST_CONTROL);
	mips_ejtag_drscan_32_out(ctx->ejtag_info, ejtag_ctrl);

	retval = jtag_execute_queue();
	if (retval != ERROR_OK)
		return retval;

	if ((address >= MIPS32_PRACC_PARAM_IN)
		&& (address <= MIPS32_PRACC_PARAM_IN + ctx->num_iparam * 4)) {
		offset = (address - MIPS32_PRACC_PARAM_IN) / 4;
		ctx->local_iparam[offset] = data;
	} else if ((address >= MIPS32_PRACC_PARAM_OUT)
		&& (address <= MIPS32_PRACC_PARAM_OUT + ctx->num_oparam * 4)) {
		offset = (address - MIPS32_PRACC_PARAM_OUT) / 4;
		ctx->local_oparam[offset] = data;
	} else if (address == MIPS32_PRACC_STACK) {
		/* save data onto our stack */
		ctx->stack[ctx->stack_offset++] = data;
	} else {
		LOG_ERROR("Error writing unexpected address 0x%8.8" PRIx32 "", address);
		return ERROR_JTAG_DEVICE_ERROR;
	}

	return ERROR_OK;
}

int mips32_pracc_exec(struct mips_ejtag *ejtag_info, int code_len, const uint32_t *code,
		int num_param_in, uint32_t *param_in, int num_param_out, uint32_t *param_out, int cycle)
{
	uint32_t ejtag_ctrl;
	uint32_t address, data;
	struct mips32_pracc_context ctx;
	int retval;
	int pass = 0;

	ctx.local_iparam = param_in;
	ctx.local_oparam = param_out;
	ctx.num_iparam = num_param_in;
	ctx.num_oparam = num_param_out;
	ctx.code = code;
	ctx.code_len = code_len;
	ctx.ejtag_info = ejtag_info;
	ctx.stack_offset = 0;

	while (1) {
		retval = wait_for_pracc_rw(ejtag_info, &ejtag_ctrl);
		if (retval != ERROR_OK)
			return retval;

		address = data = 0;
		mips_ejtag_set_instr(ejtag_info, EJTAG_INST_ADDRESS);
		retval = mips_ejtag_drscan_32(ejtag_info, &address);
		if (retval != ERROR_OK)
			return retval;

		/* Check for read or write */
		if (ejtag_ctrl & EJTAG_CTRL_PRNW) {
			retval = mips32_pracc_exec_write(&ctx, address);
			if (retval != ERROR_OK)
				return retval;
		} else {
			/* Check to see if its reading at the debug vector. The first pass through
			 * the module is always read at the vector, so the first one we allow.  When
			 * the second read from the vector occurs we are done and just exit. */
			if ((address == MIPS32_PRACC_TEXT) && (pass++))
				break;

			retval = mips32_pracc_exec_read(&ctx, address);
			if (retval != ERROR_OK)
				return retval;
		}

		if (cycle == 0)
			break;
	}

	/* stack sanity check */
	if (ctx.stack_offset != 0)
		LOG_DEBUG("Pracc Stack not zero");

	return ERROR_OK;
}

int mips32_pracc_read_mem(struct mips_ejtag *ejtag_info, uint32_t addr, int size, int count, void *buf)
{
	switch (size) {
		case 1:
			return mips32_pracc_read_mem8(ejtag_info, addr, count, (uint8_t *)buf);
		case 2:
			return mips32_pracc_read_mem16(ejtag_info, addr, count, (uint16_t *)buf);
		case 4:
			if (count == 1)
				return mips32_pracc_read_u32(ejtag_info, addr, (uint32_t *)buf);
			else
				return mips32_pracc_read_mem32(ejtag_info, addr, count, (uint32_t *)buf);
	}

	return ERROR_OK;
}

static int mips32_pracc_read_mem32(struct mips_ejtag *ejtag_info, uint32_t addr, int count, uint32_t *buf)
{
	static const uint32_t code[] = {
															/* start: */
		MIPS32_MTC0(15, 31, 0),								/* move $15 to COP0 DeSave */
		MIPS32_LUI(15, UPPER16(MIPS32_PRACC_STACK)),		/* $15 = MIPS32_PRACC_STACK */
		MIPS32_ORI(15, 15, LOWER16(MIPS32_PRACC_STACK)),
		MIPS32_SW(8, 0, 15),								/* sw $8,($15) */
		MIPS32_SW(9, 0, 15),								/* sw $9,($15) */
		MIPS32_SW(10, 0, 15),								/* sw $10,($15) */
		MIPS32_SW(11, 0, 15),								/* sw $11,($15) */

		MIPS32_LUI(8, UPPER16(MIPS32_PRACC_PARAM_IN)),		/* $8 = MIPS32_PRACC_PARAM_IN */
		MIPS32_ORI(8, 8, LOWER16(MIPS32_PRACC_PARAM_IN)),
		MIPS32_LW(9, 0, 8),									/* $9 = mem[$8]; read addr */
		MIPS32_LW(10, 4, 8),								/* $10 = mem[$8 + 4]; read count */
		MIPS32_LUI(11, UPPER16(MIPS32_PRACC_PARAM_OUT)),	/* $11 = MIPS32_PRACC_PARAM_OUT */
		MIPS32_ORI(11, 11, LOWER16(MIPS32_PRACC_PARAM_OUT)),
															/* loop: */
		MIPS32_BEQ(0, 10, 8),								/* beq 0, $10, end */
		MIPS32_NOP,

		MIPS32_LW(8, 0, 9),									/* lw $8,0($9), Load $8 with the word @mem[$9] */
		MIPS32_SW(8, 0, 11),								/* sw $8,0($11) */

		MIPS32_ADDI(10, 10, NEG16(1)),						/* $10-- */
		MIPS32_ADDI(9, 9, 4),								/* $1 += 4 */
		MIPS32_ADDI(11, 11, 4),								/* $11 += 4 */

		MIPS32_B(NEG16(8)),									/* b loop */
		MIPS32_NOP,
															/* end: */
		MIPS32_LW(11, 0, 15),								/* lw $11,($15) */
		MIPS32_LW(10, 0, 15),								/* lw $10,($15) */
		MIPS32_LW(9, 0, 15),								/* lw $9,($15) */
		MIPS32_LW(8, 0, 15),								/* lw $8,($15) */
		MIPS32_B(NEG16(27)),								/* b start */
		MIPS32_MFC0(15, 31, 0),								/* move COP0 DeSave to $15 */
	};

	int retval = ERROR_OK;
	int blocksize;
	int wordsread;
	uint32_t param_in[2];

	wordsread = 0;

	while (count > 0) {
		blocksize = count;
		if (count > 0x400)
			blocksize = 0x400;

		param_in[0] = addr;
		param_in[1] = blocksize;

		retval = mips32_pracc_exec(ejtag_info, ARRAY_SIZE(code), code,
				ARRAY_SIZE(param_in), param_in, blocksize, &buf[wordsread], 1);
		if (retval != ERROR_OK)
			return retval;

		count -= blocksize;
		addr += blocksize*sizeof(uint32_t);
		wordsread += blocksize;
	}

	return retval;
}

static int mips32_pracc_read_u32(struct mips_ejtag *ejtag_info, uint32_t addr, uint32_t *buf)
{
	static const uint32_t code[] = {
															/* start: */
		MIPS32_MTC0(15, 31, 0),								/* move $15 to COP0 DeSave */
		MIPS32_LUI(15, UPPER16(MIPS32_PRACC_STACK)),		/* $15 = MIPS32_PRACC_STACK */
		MIPS32_ORI(15, 15, LOWER16(MIPS32_PRACC_STACK)),
		MIPS32_SW(8, 0, 15),								/* sw $8,($15) */

		MIPS32_LW(8, NEG16(MIPS32_PRACC_STACK-MIPS32_PRACC_PARAM_IN), 15), /* load R8 @ param_in[0] = address */

		MIPS32_LW(8, 0, 8),									/* lw $8,0($8), Load $8 with the word @mem[$8] */
		MIPS32_SW(8, NEG16(MIPS32_PRACC_STACK - MIPS32_PRACC_PARAM_OUT), 15), /* store R8 @ param_out[0] */

		MIPS32_LW(8, 0, 15),								/* lw $8,($15) */
		MIPS32_B(NEG16(9)),									/* b start */
		MIPS32_MFC0(15, 31, 0),								/* move COP0 DeSave to $15 */
	};

	int retval = ERROR_OK;
	uint32_t param_in[1];

	param_in[0] = addr;

	retval = mips32_pracc_exec(ejtag_info, ARRAY_SIZE(code), code,
			ARRAY_SIZE(param_in), param_in, 1, buf, 1);
	if (retval != ERROR_OK)
		return retval;

	return retval;
}

static int mips32_pracc_read_mem16(struct mips_ejtag *ejtag_info, uint32_t addr, int count, uint16_t *buf)
{
	static const uint32_t code[] = {
															/* start: */
		MIPS32_MTC0(15, 31, 0),								/* move $15 to COP0 DeSave */
		MIPS32_LUI(15, UPPER16(MIPS32_PRACC_STACK)),		/* $15 = MIPS32_PRACC_STACK */
		MIPS32_ORI(15, 15, LOWER16(MIPS32_PRACC_STACK)),
		MIPS32_SW(8, 0, 15),								/* sw $8,($15) */
		MIPS32_SW(9, 0, 15),								/* sw $9,($15) */
		MIPS32_SW(10, 0, 15),								/* sw $10,($15) */
		MIPS32_SW(11, 0, 15),								/* sw $11,($15) */

		MIPS32_LUI(8, UPPER16(MIPS32_PRACC_PARAM_IN)),		/* $8 = MIPS32_PRACC_PARAM_IN */
		MIPS32_ORI(8, 8, LOWER16(MIPS32_PRACC_PARAM_IN)),
		MIPS32_LW(9, 0, 8),									/* $9 = mem[$8]; read addr */
		MIPS32_LW(10, 4, 8),								/* $10 = mem[$8 + 4]; read count */
		MIPS32_LUI(11, UPPER16(MIPS32_PRACC_PARAM_OUT)),	/* $11 = MIPS32_PRACC_PARAM_OUT */
		MIPS32_ORI(11, 11, LOWER16(MIPS32_PRACC_PARAM_OUT)),
															/* loop: */
		MIPS32_BEQ(0, 10, 8),								/* beq 0, $10, end */
		MIPS32_NOP,

		MIPS32_LHU(8, 0, 9),								/* lw $8,0($9), Load $8 with the halfword @mem[$9] */
		MIPS32_SW(8, 0, 11),								/* sw $8,0($11) */

		MIPS32_ADDI(10, 10, NEG16(1)),						/* $10-- */
		MIPS32_ADDI(9, 9, 2),								/* $9 += 2 */
		MIPS32_ADDI(11, 11, 4),								/* $11 += 4 */
		MIPS32_B(NEG16(8)),									/* b loop */
		MIPS32_NOP,
															/* end: */
		MIPS32_LW(11, 0, 15),								/* lw $11,($15) */
		MIPS32_LW(10, 0, 15),								/* lw $10,($15) */
		MIPS32_LW(9, 0, 15),								/* lw $9,($15) */
		MIPS32_LW(8, 0, 15),								/* lw $8,($15) */
		MIPS32_B(NEG16(27)),								/* b start */
		MIPS32_MFC0(15, 30, 0),								/* move COP0 DeSave to $15 */
	};

	/* TODO remove array */
	uint32_t *param_out = malloc(count * sizeof(uint32_t));
	if (param_out == NULL) {
		LOG_ERROR("Out of memory");
		return ERROR_FAIL;
	}

	int retval = ERROR_OK;
	int blocksize;
	int hwordsread = 0;
	uint32_t param_in[2];

	while (count > 0) {
		blocksize = count;
		if (count > 0x400)
			blocksize = 0x400;

		param_in[0] = addr;
		param_in[1] = blocksize;

		retval = mips32_pracc_exec(ejtag_info, ARRAY_SIZE(code), code,
			ARRAY_SIZE(param_in), param_in, blocksize, &param_out[hwordsread], 1);

		if (retval != ERROR_OK)
			return retval;

		count -= blocksize;
		addr += blocksize*sizeof(uint16_t);
		hwordsread += blocksize;
	}

	int i;
	for (i = 0; i < hwordsread; i++)
		buf[i] = param_out[i];

	free(param_out);
	return retval;
}

static int mips32_pracc_read_mem8(struct mips_ejtag *ejtag_info, uint32_t addr, int count, uint8_t *buf)
{
	static const uint32_t code[] = {
															/* start: */
		MIPS32_MTC0(15, 31, 0),								/* move $15 to COP0 DeSave */
		MIPS32_LUI(15, UPPER16(MIPS32_PRACC_STACK)),		/* $15 = MIPS32_PRACC_STACK */
		MIPS32_ORI(15, 15, LOWER16(MIPS32_PRACC_STACK)),
		MIPS32_SW(8, 0, 15),								/* sw $8,($15) */
		MIPS32_SW(9, 0, 15),								/* sw $9,($15) */
		MIPS32_SW(10, 0, 15),								/* sw $10,($15) */
		MIPS32_SW(11, 0, 15),								/* sw $11,($15) */

		MIPS32_LUI(8, UPPER16(MIPS32_PRACC_PARAM_IN)),		/* $8 = MIPS32_PRACC_PARAM_IN */
		MIPS32_ORI(8, 8, LOWER16(MIPS32_PRACC_PARAM_IN)),
		MIPS32_LW(9, 0, 8),									/* $9 = mem[$8]; read addr */
		MIPS32_LW(10, 4, 8),								/* $10 = mem[$8 + 4]; read count */
		MIPS32_LUI(11, UPPER16(MIPS32_PRACC_PARAM_OUT)),	/* $11 = MIPS32_PRACC_PARAM_OUT */
		MIPS32_ORI(11, 11, LOWER16(MIPS32_PRACC_PARAM_OUT)),
															/* loop: */
		MIPS32_BEQ(0, 10, 8),								/* beq 0, $10, end */
		MIPS32_NOP,

		MIPS32_LBU(8, 0, 9),								/* lw $8,0($9), Load t4 with the byte @mem[t1] */
		MIPS32_SW(8, 0, 11),								/* sw $8,0($11) */

		MIPS32_ADDI(10, 10, NEG16(1)),						/* $10-- */
		MIPS32_ADDI(9, 9, 1),								/* $9 += 1 */
		MIPS32_ADDI(11, 11, 4),								/* $11 += 4 */
		MIPS32_B(NEG16(8)),									/* b loop */
		MIPS32_NOP,
															/* end: */
		MIPS32_LW(11, 0, 15),								/* lw $11,($15) */
		MIPS32_LW(10, 0, 15),								/* lw $10,($15) */
		MIPS32_LW(9, 0, 15),								/* lw $9,($15) */
		MIPS32_LW(8, 0, 15),								/* lw $8,($15) */
		MIPS32_B(NEG16(27)),								/* b start */
		MIPS32_MFC0(15, 31, 0),								/* move COP0 DeSave to $15 */
	};

	/* TODO remove array */
	uint32_t *param_out = malloc(count * sizeof(uint32_t));
	if (param_out == NULL) {
		LOG_ERROR("Out of memory");
		return ERROR_FAIL;
	}

	int retval = ERROR_OK;
	int blocksize;
	uint32_t param_in[2];
	int bytesread = 0;

	while (count > 0) {
		blocksize = count;
		if (count > 0x400)
			blocksize = 0x400;

		param_in[0] = addr;
		param_in[1] = blocksize;

		retval = mips32_pracc_exec(ejtag_info, ARRAY_SIZE(code), code,
			ARRAY_SIZE(param_in), param_in, count, &param_out[bytesread], 1);

		if (retval != ERROR_OK)
			return retval;

		count -= blocksize;
		addr += blocksize;
		bytesread += blocksize;
	}
	int i;
	for (i = 0; i < bytesread; i++)
		buf[i] = param_out[i];

	free(param_out);
	return retval;
}

int mips32_cp0_read(struct mips_ejtag *ejtag_info, uint32_t *val, uint32_t cp0_reg, uint32_t cp0_sel)
{
	/**
	 * Do not make this code static, but regenerate it every time,
	 * as 5th element has to be changed to add parameters
	 */
	uint32_t code[] = {
															/* start: */
		MIPS32_MTC0(15, 31, 0),								/* move $15 to COP0 DeSave */
		MIPS32_LUI(15, UPPER16(MIPS32_PRACC_STACK)),		/* $15 = MIPS32_PRACC_STACK */
		MIPS32_ORI(15, 15, LOWER16(MIPS32_PRACC_STACK)),
		MIPS32_SW(8, 0, 15),								/* sw $8,($15) */
		MIPS32_SW(9, 0, 15),								/* sw $9,($15) */

		/* 5 */ MIPS32_MFC0(8, 0, 0),						/* move COP0 [cp0_reg select] to $8 */

		MIPS32_LUI(9, UPPER16(MIPS32_PRACC_PARAM_OUT)),		/* $11 = MIPS32_PRACC_PARAM_OUT */
		MIPS32_ORI(9, 9, LOWER16(MIPS32_PRACC_PARAM_OUT)),
		MIPS32_SW(8, 0, 9),									/* sw $8,0($9) */

		MIPS32_LW(9, 0, 15),								/* lw $9,($15) */
		MIPS32_LW(8, 0, 15),								/* lw $8,($15) */
		MIPS32_B(NEG16(12)),								/* b start */
		MIPS32_MFC0(15, 31, 0),								/* move COP0 DeSave to $15 */
	};

	/**
	 * Note that our input parametes cp0_reg and cp0_sel
	 * are numbers (not gprs) which make part of mfc0 instruction opcode.
	 *
	 * These are not fix, but can be different for each mips32_cp0_read() function call,
	 * and that is why we must insert them directly into opcode,
	 * i.e. we can not pass it on EJTAG microprogram stack (via param_in),
	 * and put them into the gprs later from MIPS32_PRACC_STACK
	 * because mfc0 do not use gpr as a parameter for the cp0_reg and select part,
	 * but plain (immediate) number.
	 *
	 * MIPS32_MTC0 is implemented via MIPS32_R_INST macro.
	 * In order to insert our parameters, we must change rd and funct fields.
	 */
	code[5] |= (cp0_reg << 11) | cp0_sel;  /* change rd and funct of MIPS32_R_INST macro */

	/* TODO remove array */
	uint32_t *param_out = val;
	int retval;

	retval = mips32_pracc_exec(ejtag_info, ARRAY_SIZE(code), code, 0, NULL, 1, param_out, 1);

	return retval;
}

int mips32_cp0_write(struct mips_ejtag *ejtag_info,
		uint32_t val, uint32_t cp0_reg, uint32_t cp0_sel)
{
	uint32_t code[] = {
															/* start: */
		MIPS32_MTC0(15, 31, 0),								/* move $15 to COP0 DeSave */
		MIPS32_LUI(15, UPPER16(MIPS32_PRACC_STACK)),		/* $15 = MIPS32_PRACC_STACK */
		MIPS32_ORI(15, 15, LOWER16(MIPS32_PRACC_STACK)),
		MIPS32_SW(8, 0, 15),								/* sw $8,($15) */
		MIPS32_SW(9, 0, 15),								/* sw $9,($15) */

		MIPS32_LUI(8, UPPER16(MIPS32_PRACC_PARAM_IN)),		/* $8 = MIPS32_PRACC_PARAM_IN */
		MIPS32_ORI(8, 8, LOWER16(MIPS32_PRACC_PARAM_IN)),
		MIPS32_LW(9, 0, 8),									/* Load write val to $9 */

		/* 8 */ MIPS32_MTC0(9, 0, 0),						/* move $9 to COP0 [cp0_reg select] */

		MIPS32_LW(9, 0, 15),								/* lw $9,($15) */
		MIPS32_LW(8, 0, 15),								/* lw $8,($15) */
		MIPS32_B(NEG16(12)),								/* b start */
		MIPS32_MFC0(15, 31, 0),								/* move COP0 DeSave to $15 */
	};

	/**
	 * Note that MIPS32_MTC0 macro is implemented via MIPS32_R_INST macro.
	 * In order to insert our parameters, we must change rd and funct fields.
	 */
	code[8] |= (cp0_reg << 11) | cp0_sel;  /* change rd and funct fields of MIPS32_R_INST macro */

	/* TODO remove array */
	uint32_t *param_in = malloc(1 * sizeof(uint32_t));
	int retval;
	param_in[0] = val;

	retval = mips32_pracc_exec(ejtag_info, ARRAY_SIZE(code), code, 1, param_in, 0, NULL, 1);

	free(param_in);

	return retval;
}

/**
 * \b mips32_pracc_sync_cache
 *
 * Synchronize Caches to Make Instruction Writes Effective
 * (ref. doc. MIPS32 Architecture For Programmers Volume II: The MIPS32 Instruction Set,
 *  Document Number: MD00086, Revision 2.00, June 9, 2003)
 *
 * When the instruction stream is written, the SYNCI instruction should be used
 * in conjunction with other instructions to make the newly-written instructions effective.
 *
 * Explanation :
 * A program that loads another program into memory is actually writing the D- side cache.
 * The instructions it has loaded can't be executed until they reach the I-cache.
 *
 * After the instructions have been written, the loader should arrange
 * to write back any containing D-cache line and invalidate any locations
 * already in the I-cache.
 *
 * You can do that with cache instructions, but those instructions are only available in kernel mode,
 * and a loader writing instructions for the use of its own process need not be privileged software.
 *
 * In the latest MIPS32/64 CPUs, MIPS provides the synci instruction,
 * which does the whole job for a cache-line-sized chunk of the memory you just loaded:
 * That is, it arranges a D-cache write-back and an I-cache invalidate.
 *
 * To employ synci at user level, you need to know the size of a cache line,
 * and that can be obtained with a rdhwr SYNCI_Step
 * from one of the standard “hardware registers”.
 */
static int mips32_pracc_sync_cache(struct mips_ejtag *ejtag_info,
		uint32_t start_addr, uint32_t end_addr)
{
	static const uint32_t code[] = {
															/* start: */
		MIPS32_MTC0(15, 31, 0),								/* move $15 to COP0 DeSave */
		MIPS32_LUI(15, UPPER16(MIPS32_PRACC_STACK)),		/* $15 = MIPS32_PRACC_STACK */
		MIPS32_ORI(15, 15, LOWER16(MIPS32_PRACC_STACK)),
		MIPS32_SW(8, 0, 15),								/* sw $8,($15) */
		MIPS32_SW(9, 0, 15),								/* sw $9,($15) */
		MIPS32_SW(10, 0, 15),								/* sw $10,($15) */
		MIPS32_SW(11, 0, 15),								/* sw $11,($15) */

		MIPS32_LUI(8, UPPER16(MIPS32_PRACC_PARAM_IN)),		/* $8 = MIPS32_PRACC_PARAM_IN */
		MIPS32_ORI(8, 8, LOWER16(MIPS32_PRACC_PARAM_IN)),
		MIPS32_LW(9, 0, 8),									/* Load write start_addr to $9 */
		MIPS32_LW(10, 4, 8),								/* Load write end_addr to $10 */

		MIPS32_RDHWR(11, MIPS32_SYNCI_STEP),				/* $11 = MIPS32_SYNCI_STEP */
		MIPS32_BEQ(11, 0, 6),								/* beq $11, $0, end */
		MIPS32_NOP,
															/* synci_loop : */
		MIPS32_SYNCI(0, 9),									/* synci 0($9) */
		MIPS32_SLTU(8, 10, 9),								/* sltu $8, $10, $9  # $8 = $10 < $9 ? 1 : 0 */
		MIPS32_BNE(8, 0, NEG16(3)),							/* bne $8, $0, synci_loop */
		MIPS32_ADDU(9, 9, 11),								/* $9 += MIPS32_SYNCI_STEP */
		MIPS32_SYNC,
															/* end: */
		MIPS32_LW(11, 0, 15),								/* lw $11,($15) */
		MIPS32_LW(10, 0, 15),								/* lw $10,($15) */
		MIPS32_LW(9, 0, 15),								/* lw $9,($15) */
		MIPS32_LW(8, 0, 15),								/* lw $8,($15) */
		MIPS32_B(NEG16(24)),								/* b start */
		MIPS32_MFC0(15, 31, 0),								/* move COP0 DeSave to $15 */
	};

	/* TODO remove array */
	uint32_t *param_in = malloc(2 * sizeof(uint32_t));
	int retval;
	param_in[0] = start_addr;
	param_in[1] = end_addr;

	retval = mips32_pracc_exec(ejtag_info, ARRAY_SIZE(code), code, 2, param_in, 0, NULL, 1);

	free(param_in);

	return retval;
}

/**
 * \b mips32_pracc_clean_invalidate_cache
 *
 * Writeback D$ and Invalidate I$
 * so that the instructions written can be visible to CPU
 */
static int mips32_pracc_clean_invalidate_cache(struct mips_ejtag *ejtag_info,
													uint32_t start_addr, uint32_t end_addr)
{
	static const uint32_t code[] = {
															/* start: */
		MIPS32_MTC0(15, 31, 0),								/* move $15 to COP0 DeSave */
		MIPS32_LUI(15, UPPER16(MIPS32_PRACC_STACK)),		/* $15 = MIPS32_PRACC_STACK */
		MIPS32_ORI(15, 15, LOWER16(MIPS32_PRACC_STACK)),
		MIPS32_SW(8, 0, 15),								/* sw $8,($15) */
		MIPS32_SW(9, 0, 15),								/* sw $9,($15) */
		MIPS32_SW(10, 0, 15),								/* sw $10,($15) */
		MIPS32_SW(11, 0, 15),								/* sw $11,($15) */

		MIPS32_LUI(8, UPPER16(MIPS32_PRACC_PARAM_IN)),		/* $8 = MIPS32_PRACC_PARAM_IN */
		MIPS32_ORI(8, 8, LOWER16(MIPS32_PRACC_PARAM_IN)),
		MIPS32_LW(9, 0, 8),									/* Load write start_addr to $9 */
		MIPS32_LW(10, 4, 8),								/* Load write end_addr to $10 */
		MIPS32_LW(11, 8, 8),								/* Load write clsiz to $11 */

															/* cache_loop: */
		MIPS32_SLTU(8, 10, 9),								/* sltu $8, $10, $9  :  $8 <- $10 < $9 ? */
		MIPS32_BGTZ(8, 6),									/* bgtz $8, end */
		MIPS32_NOP,

		MIPS32_CACHE(MIPS32_CACHE_D_HIT_WRITEBACK, 0, 9),		/* cache Hit_Writeback_D, 0($9) */
		MIPS32_CACHE(MIPS32_CACHE_I_HIT_INVALIDATE, 0, 9),	/* cache Hit_Invalidate_I, 0($9) */

		MIPS32_ADDU(9, 9, 11),								/* $9 += $11 */

		MIPS32_B(NEG16(7)),									/* b cache_loop */
		MIPS32_NOP,
															/* end: */
		MIPS32_LW(11, 0, 15),								/* lw $11,($15) */
		MIPS32_LW(10, 0, 15),								/* lw $10,($15) */
		MIPS32_LW(9, 0, 15),								/* lw $9,($15) */
		MIPS32_LW(8, 0, 15),								/* lw $8,($15) */
		MIPS32_B(NEG16(25)),								/* b start */
		MIPS32_MFC0(15, 31, 0),								/* move COP0 DeSave to $15 */
	};

	/**
	 * Find cache line size in bytes
	 */
	uint32_t conf;
	uint32_t dl, clsiz;

	mips32_cp0_read(ejtag_info, &conf, 16, 1);
	dl = (conf & MIPS32_CONFIG1_DL_MASK) >> MIPS32_CONFIG1_DL_SHIFT;

	/* dl encoding : dl=1 => 4 bytes, dl=2 => 8 bytes, etc... */
	clsiz = 0x2 << dl;

	/* TODO remove array */
	uint32_t *param_in = malloc(3 * sizeof(uint32_t));
	int retval;
	param_in[0] = start_addr;
	param_in[1] = end_addr;
	param_in[2] = clsiz;

	retval = mips32_pracc_exec(ejtag_info, ARRAY_SIZE(code), code, 3, param_in, 0, NULL, 1);

	free(param_in);

	return retval;
}


int mips32_pracc_write_mem(struct mips_ejtag *ejtag_info, uint32_t addr, int size, int count, void *buf)
{
	int retval;

	switch (size) {
		case 1:
			retval = mips32_pracc_write_mem8(ejtag_info, addr, count, (uint8_t *)buf);
			break;
		case 2:
			retval = mips32_pracc_write_mem16(ejtag_info, addr, count, (uint16_t *)buf);
			break;
		case 4:
			if (count == 1)
				retval = mips32_pracc_write_u32(ejtag_info, addr, (uint32_t *)buf);
			else
				retval = mips32_pracc_write_mem32(ejtag_info, addr, count, (uint32_t *)buf);
			break;
		default:
			retval = ERROR_FAIL;
	}

	/**
	 * If we are in the cachable regoion and cache is activated,
	 * we must clean D$ + invalidate I$ after we did the write,
	 * so that changes do not continue to live only in D$, but to be
	 * replicated in I$ also (maybe we wrote the istructions)
	 */
	uint32_t conf = 0;
	int cached = 0;

	if ((KSEGX(addr) == KSEG1) || ((addr >= 0xff200000) && (addr <= 0xff3fffff)))
		return retval; /*Nothing to do*/

	mips32_cp0_read(ejtag_info, &conf, 16, 0);

	switch (KSEGX(addr)) {
		case KUSEG:
			cached = (conf & MIPS32_CONFIG0_KU_MASK) >> MIPS32_CONFIG0_KU_SHIFT;
			break;
		case KSEG0:
			cached = (conf & MIPS32_CONFIG0_K0_MASK) >> MIPS32_CONFIG0_K0_SHIFT;
			break;
		case KSEG2:
		case KSEG3:
			cached = (conf & MIPS32_CONFIG0_K23_MASK) >> MIPS32_CONFIG0_K23_SHIFT;
			break;
		default:
			/* what ? */
			break;
	}

	/**
	 * Check cachablitiy bits coherency algorithm -
	 * is the region cacheable or uncached.
	 * If cacheable we have to synchronize the cache
	 */
	if (cached == 0x3) {
		uint32_t start_addr, end_addr;
		uint32_t rel;

		start_addr = addr;
		end_addr = addr + count * size;

		/** select cache synchronisation mechanism based on Architecture Release */
		rel = (conf & MIPS32_CONFIG0_AR_MASK) >> MIPS32_CONFIG0_AR_SHIFT;
		switch (rel) {
			case MIPS32_ARCH_REL1:
				/* MIPS32/64 Release 1 - we must use cache instruction */
				mips32_pracc_clean_invalidate_cache(ejtag_info, start_addr, end_addr);
				break;
			case MIPS32_ARCH_REL2:
				/* MIPS32/64 Release 2 - we can use synci instruction */
				mips32_pracc_sync_cache(ejtag_info, start_addr, end_addr);
				break;
			default:
				/* what ? */
				break;
		}
	}

	return retval;
}

static int mips32_pracc_write_mem32(struct mips_ejtag *ejtag_info, uint32_t addr, int count, uint32_t *buf)
{
	static const uint32_t code[] = {
															/* start: */
		MIPS32_MTC0(15, 31, 0),								/* move $15 to COP0 DeSave */
		MIPS32_LUI(15, UPPER16(MIPS32_PRACC_STACK)),		/* $15 = MIPS32_PRACC_STACK */
		MIPS32_ORI(15, 15, LOWER16(MIPS32_PRACC_STACK)),
		MIPS32_SW(8, 0, 15),								/* sw $8,($15) */
		MIPS32_SW(9, 0, 15),								/* sw $9,($15) */
		MIPS32_SW(10, 0, 15),								/* sw $10,($15) */
		MIPS32_SW(11, 0, 15),								/* sw $11,($15) */

		MIPS32_ADDI(8, 15, NEG16(MIPS32_PRACC_STACK-MIPS32_PRACC_PARAM_IN)),  /* $8= MIPS32_PRACC_PARAM_IN */
		MIPS32_LW(9, 0, 8),									/* Load write addr to $9 */
		MIPS32_LW(10, 4, 8),								/* Load write count to $10 */
		MIPS32_ADDI(8, 8, 8),								/* $8 += 8 beginning of data */

															/* loop: */
		MIPS32_LW(11, 0, 8),								/* lw $11,0($8), Load $11 with the word @mem[$8] */
		MIPS32_SW(11, 0, 9),								/* sw $11,0($9) */

		MIPS32_ADDI(9, 9, 4),								/* $9 += 4 */
		MIPS32_BNE(10, 9, NEG16(4)),						/* bne $10, $9, loop */
		MIPS32_ADDI(8, 8, 4),								/* $8 += 4 */

															/* end: */
		MIPS32_LW(11, 0, 15),								/* lw $11,($15) */
		MIPS32_LW(10, 0, 15),								/* lw $10,($15) */
		MIPS32_LW(9, 0, 15),								/* lw $9,($15) */
		MIPS32_LW(8, 0, 15),								/* lw $8,($15) */
		MIPS32_B(NEG16(21)),								/* b start */
		MIPS32_MFC0(15, 31, 0),								/* move COP0 DeSave to $15 */
	};

	/* TODO remove array */
	uint32_t *param_in = malloc((count + 2) * sizeof(uint32_t));
	param_in[0] = addr;
	param_in[1] = addr + (count * sizeof(uint32_t));	/* last address */

	memcpy(&param_in[2], buf, count * sizeof(uint32_t));

	int retval;
	retval = mips32_pracc_exec(ejtag_info, ARRAY_SIZE(code), code,
		count + 2, param_in, 0, NULL, 1);

	free(param_in);

	return retval;
}

static int mips32_pracc_write_u32(struct mips_ejtag *ejtag_info, uint32_t addr, uint32_t *buf)
{
	static const uint32_t code[] = {
															/* start: */
		MIPS32_MTC0(15, 31, 0),								/* move $15 to COP0 DeSave */
		MIPS32_LUI(15, UPPER16(MIPS32_PRACC_STACK)),		/* $15 = MIPS32_PRACC_STACK */
		MIPS32_ORI(15, 15, LOWER16(MIPS32_PRACC_STACK)),
		MIPS32_SW(8, 0, 15),								/* sw $8,($15) */
		MIPS32_SW(9, 0, 15),								/* sw $9,($15) */

		MIPS32_LW(8, NEG16((MIPS32_PRACC_STACK-MIPS32_PRACC_PARAM_IN)-4), 15),	/* load R8 @ param_in[1] = data */
		MIPS32_LW(9, NEG16(MIPS32_PRACC_STACK-MIPS32_PRACC_PARAM_IN), 15),		/* load R9 @ param_in[0] = address */

		MIPS32_SW(8, 0, 9),									/* sw $8,0($9) */

		MIPS32_LW(9, 0, 15),								/* lw $9,($15) */
		MIPS32_LW(8, 0, 15),								/* lw $8,($15) */
		MIPS32_B(NEG16(11)),								/* b start */
		MIPS32_MFC0(15, 31, 0),								/* move COP0 DeSave to $15 */
	};

	/* TODO remove array */
	uint32_t param_in[1 + 1];
	param_in[0] = addr;
	param_in[1] = *buf;

	return mips32_pracc_exec(ejtag_info, ARRAY_SIZE(code), code,
		ARRAY_SIZE(param_in), param_in, 0, NULL, 1);
}

static int mips32_pracc_write_mem16(struct mips_ejtag *ejtag_info, uint32_t addr, int count, uint16_t *buf)
{
	static const uint32_t code[] = {
															/* start: */
		MIPS32_MTC0(15, 31, 0),								/* move $15 to COP0 DeSave */
		MIPS32_LUI(15, UPPER16(MIPS32_PRACC_STACK)),		/* $15 = MIPS32_PRACC_STACK */
		MIPS32_ORI(15, 15, LOWER16(MIPS32_PRACC_STACK)),
		MIPS32_SW(8, 0, 15),								/* sw $8,($15) */
		MIPS32_SW(9, 0, 15),								/* sw $9,($15) */
		MIPS32_SW(10, 0, 15),								/* sw $10,($15) */
		MIPS32_SW(11, 0, 15),								/* sw $11,($15) */

		MIPS32_LUI(8, UPPER16(MIPS32_PRACC_PARAM_IN)),		/* $8 = MIPS32_PRACC_PARAM_IN */
		MIPS32_ORI(8, 8, LOWER16(MIPS32_PRACC_PARAM_IN)),
		MIPS32_LW(9, 0, 8),									/* Load write addr to $9 */
		MIPS32_LW(10, 4, 8),								/* Load write count to $10 */
		MIPS32_ADDI(8, 8, 8),								/* $8 += 8 */
															/* loop: */
		MIPS32_BEQ(0, 10, 8),								/* beq $0, $10, end */
		MIPS32_NOP,

		MIPS32_LW(11, 0, 8),								/* lw $11,0($8), Load $11 with the word @mem[$8] */
		MIPS32_SH(11, 0, 9),								/* sh $11,0($9) */

		MIPS32_ADDI(10, 10, NEG16(1)),						/* $10-- */
		MIPS32_ADDI(9, 9, 2),								/* $9 += 2 */
		MIPS32_ADDI(8, 8, 4),								/* $8 += 4 */

		MIPS32_B(NEG16(8)),									/* b loop */
		MIPS32_NOP,
															/* end: */
		MIPS32_LW(11, 0, 15),								/* lw $11,($15) */
		MIPS32_LW(10, 0, 15),								/* lw $10,($15) */
		MIPS32_LW(9, 0, 15),								/* lw $9,($15) */
		MIPS32_LW(8, 0, 15),								/* lw $8,($15) */
		MIPS32_B(NEG16(26)),								/* b start */
		MIPS32_MFC0(15, 31, 0),								/* move COP0 DeSave to $15 */
	};

	/* TODO remove array */
	uint32_t *param_in = malloc((count + 2) * sizeof(uint32_t));
	int i;
	param_in[0] = addr;
	param_in[1] = count;

	for (i = 0; i < count; i++)
		param_in[i + 2] = buf[i];

	int retval;
	retval = mips32_pracc_exec(ejtag_info, ARRAY_SIZE(code), code,
		count + 2, param_in, 0, NULL, 1);

	free(param_in);

	return retval;
}

static int mips32_pracc_write_mem8(struct mips_ejtag *ejtag_info, uint32_t addr, int count, uint8_t *buf)
{
	static const uint32_t code[] = {
															/* start: */
		MIPS32_MTC0(15, 31, 0),								/* move $15 to COP0 DeSave */
		MIPS32_LUI(15, UPPER16(MIPS32_PRACC_STACK)),		/* $15 = MIPS32_PRACC_STACK */
		MIPS32_ORI(15, 15, LOWER16(MIPS32_PRACC_STACK)),
		MIPS32_SW(8, 0, 15),								/* sw $8,($15) */
		MIPS32_SW(9, 0, 15),								/* sw $9,($15) */
		MIPS32_SW(10, 0, 15),								/* sw $10,($15) */
		MIPS32_SW(11, 0, 15),								/* sw $11,($15) */

		MIPS32_LUI(8, UPPER16(MIPS32_PRACC_PARAM_IN)),		/* $8 = MIPS32_PRACC_PARAM_IN */
		MIPS32_ORI(8, 8, LOWER16(MIPS32_PRACC_PARAM_IN)),
		MIPS32_LW(9, 0, 8),									/* Load write addr to $9 */
		MIPS32_LW(10, 4, 8),								/* Load write count to $10 */
		MIPS32_ADDI(8, 8, 8),								/* $8 += 8 */
															/* loop: */
		MIPS32_BEQ(0, 10, 8),								/* beq $0, $10, end */
		MIPS32_NOP,

		MIPS32_LW(11, 0, 8),								/* lw $11,0($8), Load $11 with the word @mem[$8] */
		MIPS32_SB(11, 0, 9),								/* sb $11,0($9) */

		MIPS32_ADDI(10, 10, NEG16(1)),						/* $10-- */
		MIPS32_ADDI(9, 9, 1),								/* $9 += 1 */
		MIPS32_ADDI(8, 8, 4),								/* $8 += 4 */

		MIPS32_B(NEG16(8)),									/* b loop */
		MIPS32_NOP,
															/* end: */
		MIPS32_LW(11, 0, 15),								/* lw $11,($15) */
		MIPS32_LW(10, 0, 15),								/* lw $10,($15) */
		MIPS32_LW(9, 0, 15),								/* lw $9,($15) */
		MIPS32_LW(8, 0, 15),								/* lw $8,($15) */
		MIPS32_B(NEG16(26)),								/* b start */
		MIPS32_MFC0(15, 31, 0),								/* move COP0 DeSave to $15 */
	};

	/* TODO remove array */
	uint32_t *param_in = malloc((count + 2) * sizeof(uint32_t));
	int retval;
	int i;
	param_in[0] = addr;
	param_in[1] = count;

	for (i = 0; i < count; i++)
		param_in[i + 2] = buf[i];

	retval = mips32_pracc_exec(ejtag_info, ARRAY_SIZE(code), code,
		count + 2, param_in, 0, NULL, 1);

	free(param_in);

	return retval;
}

int mips32_pracc_write_regs(struct mips_ejtag *ejtag_info, uint32_t *regs)
{
	static const uint32_t code[] = {
														/* start: */
		MIPS32_LUI(2, UPPER16(MIPS32_PRACC_PARAM_IN)),	/* $2 = MIPS32_PRACC_PARAM_IN */
		MIPS32_ORI(2, 2, LOWER16(MIPS32_PRACC_PARAM_IN)),
		MIPS32_LW(1, 1*4, 2),							/* lw $1,1*4($2) */
		MIPS32_LW(15, 15*4, 2),							/* lw $15,15*4($2) */
		MIPS32_MTC0(15, 31, 0),							/* move $15 to COP0 DeSave */
		MIPS32_LUI(15, UPPER16(MIPS32_PRACC_STACK)),	/* $15 = MIPS32_PRACC_STACK */
		MIPS32_ORI(15, 15, LOWER16(MIPS32_PRACC_STACK)),
		MIPS32_SW(1, 0, 15),							/* sw $1,($15) */
		MIPS32_LUI(1, UPPER16(MIPS32_PRACC_PARAM_IN)),	/* $1 = MIPS32_PRACC_PARAM_IN */
		MIPS32_ORI(1, 1, LOWER16(MIPS32_PRACC_PARAM_IN)),
		MIPS32_LW(3, 3*4, 1),							/* lw $3,3*4($1) */
		MIPS32_LW(4, 4*4, 1),							/* lw $4,4*4($1) */
		MIPS32_LW(5, 5*4, 1),							/* lw $5,5*4($1) */
		MIPS32_LW(6, 6*4, 1),							/* lw $6,6*4($1) */
		MIPS32_LW(7, 7*4, 1),							/* lw $7,7*4($1) */
		MIPS32_LW(8, 8*4, 1),							/* lw $8,8*4($1) */
		MIPS32_LW(9, 9*4, 1),							/* lw $9,9*4($1) */
		MIPS32_LW(10, 10*4, 1),							/* lw $10,10*4($1) */
		MIPS32_LW(11, 11*4, 1),							/* lw $11,11*4($1) */
		MIPS32_LW(12, 12*4, 1),							/* lw $12,12*4($1) */
		MIPS32_LW(13, 13*4, 1),							/* lw $13,13*4($1) */
		MIPS32_LW(14, 14*4, 1),							/* lw $14,14*4($1) */
		MIPS32_LW(16, 16*4, 1),							/* lw $16,16*4($1) */
		MIPS32_LW(17, 17*4, 1),							/* lw $17,17*4($1) */
		MIPS32_LW(18, 18*4, 1),							/* lw $18,18*4($1) */
		MIPS32_LW(19, 19*4, 1),							/* lw $19,19*4($1) */
		MIPS32_LW(20, 20*4, 1),							/* lw $20,20*4($1) */
		MIPS32_LW(21, 21*4, 1),							/* lw $21,21*4($1) */
		MIPS32_LW(22, 22*4, 1),							/* lw $22,22*4($1) */
		MIPS32_LW(23, 23*4, 1),							/* lw $23,23*4($1) */
		MIPS32_LW(24, 24*4, 1),							/* lw $24,24*4($1) */
		MIPS32_LW(25, 25*4, 1),							/* lw $25,25*4($1) */
		MIPS32_LW(26, 26*4, 1),							/* lw $26,26*4($1) */
		MIPS32_LW(27, 27*4, 1),							/* lw $27,27*4($1) */
		MIPS32_LW(28, 28*4, 1),							/* lw $28,28*4($1) */
		MIPS32_LW(29, 29*4, 1),							/* lw $29,29*4($1) */
		MIPS32_LW(30, 30*4, 1),							/* lw $30,30*4($1) */
		MIPS32_LW(31, 31*4, 1),							/* lw $31,31*4($1) */

		MIPS32_LW(2, 32*4, 1),							/* lw $2,32*4($1) */
		MIPS32_MTC0(2, 12, 0),							/* move $2 to status */
		MIPS32_LW(2, 33*4, 1),							/* lw $2,33*4($1) */
		MIPS32_MTLO(2),									/* move $2 to lo */
		MIPS32_LW(2, 34*4, 1),							/* lw $2,34*4($1) */
		MIPS32_MTHI(2),									/* move $2 to hi */
		MIPS32_LW(2, 35*4, 1),							/* lw $2,35*4($1) */
		MIPS32_MTC0(2, 8, 0),							/* move $2 to badvaddr */
		MIPS32_LW(2, 36*4, 1),							/* lw $2,36*4($1) */
		MIPS32_MTC0(2, 13, 0),							/* move $2 to cause*/
		MIPS32_LW(2, 37*4, 1),							/* lw $2,37*4($1) */
		MIPS32_MTC0(2, 24, 0),							/* move $2 to depc (pc) */

		MIPS32_LW(2, 2*4, 1),							/* lw $2,2*4($1) */
		MIPS32_LW(1, 0, 15),							/* lw $1,($15) */
		MIPS32_B(NEG16(53)),							/* b start */
		MIPS32_MFC0(15, 31, 0),							/* move COP0 DeSave to $15 */
	};

	int retval;

	retval = mips32_pracc_exec(ejtag_info, ARRAY_SIZE(code), code,
			MIPS32NUMCOREREGS, regs, 0, NULL, 1);

	return retval;
}

int mips32_pracc_read_regs(struct mips_ejtag *ejtag_info, uint32_t *regs)
{
	static const uint32_t code[] = {
														/* start: */
		MIPS32_MTC0(2, 31, 0),							/* move $2 to COP0 DeSave */
		MIPS32_LUI(2, UPPER16(MIPS32_PRACC_PARAM_OUT)),	/* $2 = MIPS32_PRACC_PARAM_OUT */
		MIPS32_ORI(2, 2, LOWER16(MIPS32_PRACC_PARAM_OUT)),
		MIPS32_SW(0, 0*4, 2),							/* sw $0,0*4($2) */
		MIPS32_SW(1, 1*4, 2),							/* sw $1,1*4($2) */
		MIPS32_SW(15, 15*4, 2),							/* sw $15,15*4($2) */
		MIPS32_MFC0(2, 31, 0),							/* move COP0 DeSave to $2 */
		MIPS32_MTC0(15, 31, 0),							/* move $15 to COP0 DeSave */
		MIPS32_LUI(15, UPPER16(MIPS32_PRACC_STACK)),	/* $15 = MIPS32_PRACC_STACK */
		MIPS32_ORI(15, 15, LOWER16(MIPS32_PRACC_STACK)),
		MIPS32_SW(1, 0, 15),							/* sw $1,($15) */
		MIPS32_SW(2, 0, 15),							/* sw $2,($15) */
		MIPS32_LUI(1, UPPER16(MIPS32_PRACC_PARAM_OUT)),	/* $1 = MIPS32_PRACC_PARAM_OUT */
		MIPS32_ORI(1, 1, LOWER16(MIPS32_PRACC_PARAM_OUT)),
		MIPS32_SW(2, 2*4, 1),							/* sw $2,2*4($1) */
		MIPS32_SW(3, 3*4, 1),							/* sw $3,3*4($1) */
		MIPS32_SW(4, 4*4, 1),							/* sw $4,4*4($1) */
		MIPS32_SW(5, 5*4, 1),							/* sw $5,5*4($1) */
		MIPS32_SW(6, 6*4, 1),							/* sw $6,6*4($1) */
		MIPS32_SW(7, 7*4, 1),							/* sw $7,7*4($1) */
		MIPS32_SW(8, 8*4, 1),							/* sw $8,8*4($1) */
		MIPS32_SW(9, 9*4, 1),							/* sw $9,9*4($1) */
		MIPS32_SW(10, 10*4, 1),							/* sw $10,10*4($1) */
		MIPS32_SW(11, 11*4, 1),							/* sw $11,11*4($1) */
		MIPS32_SW(12, 12*4, 1),							/* sw $12,12*4($1) */
		MIPS32_SW(13, 13*4, 1),							/* sw $13,13*4($1) */
		MIPS32_SW(14, 14*4, 1),							/* sw $14,14*4($1) */
		MIPS32_SW(16, 16*4, 1),							/* sw $16,16*4($1) */
		MIPS32_SW(17, 17*4, 1),							/* sw $17,17*4($1) */
		MIPS32_SW(18, 18*4, 1),							/* sw $18,18*4($1) */
		MIPS32_SW(19, 19*4, 1),							/* sw $19,19*4($1) */
		MIPS32_SW(20, 20*4, 1),							/* sw $20,20*4($1) */
		MIPS32_SW(21, 21*4, 1),							/* sw $21,21*4($1) */
		MIPS32_SW(22, 22*4, 1),							/* sw $22,22*4($1) */
		MIPS32_SW(23, 23*4, 1),							/* sw $23,23*4($1) */
		MIPS32_SW(24, 24*4, 1),							/* sw $24,24*4($1) */
		MIPS32_SW(25, 25*4, 1),							/* sw $25,25*4($1) */
		MIPS32_SW(26, 26*4, 1),							/* sw $26,26*4($1) */
		MIPS32_SW(27, 27*4, 1),							/* sw $27,27*4($1) */
		MIPS32_SW(28, 28*4, 1),							/* sw $28,28*4($1) */
		MIPS32_SW(29, 29*4, 1),							/* sw $29,29*4($1) */
		MIPS32_SW(30, 30*4, 1),							/* sw $30,30*4($1) */
		MIPS32_SW(31, 31*4, 1),							/* sw $31,31*4($1) */

		MIPS32_MFC0(2, 12, 0),							/* move status to $2 */
		MIPS32_SW(2, 32*4, 1),							/* sw $2,32*4($1) */
		MIPS32_MFLO(2),									/* move lo to $2 */
		MIPS32_SW(2, 33*4, 1),							/* sw $2,33*4($1) */
		MIPS32_MFHI(2),									/* move hi to $2 */
		MIPS32_SW(2, 34*4, 1),							/* sw $2,34*4($1) */
		MIPS32_MFC0(2, 8, 0),							/* move badvaddr to $2 */
		MIPS32_SW(2, 35*4, 1),							/* sw $2,35*4($1) */
		MIPS32_MFC0(2, 13, 0),							/* move cause to $2 */
		MIPS32_SW(2, 36*4, 1),							/* sw $2,36*4($1) */
		MIPS32_MFC0(2, 24, 0),							/* move depc (pc) to $2 */
		MIPS32_SW(2, 37*4, 1),							/* sw $2,37*4($1) */

		MIPS32_LW(2, 0, 15),							/* lw $2,($15) */
		MIPS32_LW(1, 0, 15),							/* lw $1,($15) */
		MIPS32_B(NEG16(58)),							/* b start */
		MIPS32_MFC0(15, 31, 0),							/* move COP0 DeSave to $15 */
	};

	int retval;

	retval = mips32_pracc_exec(ejtag_info, ARRAY_SIZE(code), code,
		0, NULL, MIPS32NUMCOREREGS, regs, 1);

	return retval;
}

/* fastdata upload/download requires an initialized working area
 * to load the download code; it should not be called otherwise
 * fetch order from the fastdata area
 * 1. start addr
 * 2. end addr
 * 3. data ...
 */
int mips32_pracc_fastdata_xfer(struct mips_ejtag *ejtag_info, struct working_area *source,
		int write_t, uint32_t addr, int count, uint32_t *buf)
{
	uint32_t handler_code[] = {
		/* caution when editing, table is modified below */
		/* r15 points to the start of this code */
		MIPS32_SW(8, MIPS32_FASTDATA_HANDLER_SIZE - 4, 15),
		MIPS32_SW(9, MIPS32_FASTDATA_HANDLER_SIZE - 8, 15),
		MIPS32_SW(10, MIPS32_FASTDATA_HANDLER_SIZE - 12, 15),
		MIPS32_SW(11, MIPS32_FASTDATA_HANDLER_SIZE - 16, 15),
		/* start of fastdata area in t0 */
		MIPS32_LUI(8, UPPER16(MIPS32_PRACC_FASTDATA_AREA)),
		MIPS32_ORI(8, 8, LOWER16(MIPS32_PRACC_FASTDATA_AREA)),
		MIPS32_LW(9, 0, 8),								/* start addr in t1 */
		MIPS32_LW(10, 0, 8),							/* end addr to t2 */
														/* loop: */
		/* 8 */ MIPS32_LW(11, 0, 0),					/* lw t3,[t8 | r9] */
		/* 9 */ MIPS32_SW(11, 0, 0),					/* sw t3,[r9 | r8] */
		MIPS32_BNE(10, 9, NEG16(3)),					/* bne $t2,t1,loop */
		MIPS32_ADDI(9, 9, 4),							/* addi t1,t1,4 */

		MIPS32_LW(8, MIPS32_FASTDATA_HANDLER_SIZE - 4, 15),
		MIPS32_LW(9, MIPS32_FASTDATA_HANDLER_SIZE - 8, 15),
		MIPS32_LW(10, MIPS32_FASTDATA_HANDLER_SIZE - 12, 15),
		MIPS32_LW(11, MIPS32_FASTDATA_HANDLER_SIZE - 16, 15),

		MIPS32_LUI(15, UPPER16(MIPS32_PRACC_TEXT)),
		MIPS32_ORI(15, 15, LOWER16(MIPS32_PRACC_TEXT)),
		MIPS32_JR(15),								/* jr start */
		MIPS32_MFC0(15, 31, 0),						/* move COP0 DeSave to $15 */
	};

	uint32_t jmp_code[] = {
		MIPS32_MTC0(15, 31, 0),			/* move $15 to COP0 DeSave */
		/* 1 */ MIPS32_LUI(15, 0),		/* addr of working area added below */
		/* 2 */ MIPS32_ORI(15, 15, 0),	/* addr of working area added below */
		MIPS32_JR(15),					/* jump to ram program */
		MIPS32_NOP,
	};

	int retval, i;
	uint32_t val, ejtag_ctrl, address;

	if (source->size < MIPS32_FASTDATA_HANDLER_SIZE)
		return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;

	if (write_t) {
		handler_code[8] = MIPS32_LW(11, 0, 8);	/* load data from probe at fastdata area */
		handler_code[9] = MIPS32_SW(11, 0, 9);	/* store data to RAM @ r9 */
	} else {
		handler_code[8] = MIPS32_LW(11, 0, 9);	/* load data from RAM @ r9 */
		handler_code[9] = MIPS32_SW(11, 0, 8);	/* store data to probe at fastdata area */
	}

	/* write program into RAM */
	if (write_t != ejtag_info->fast_access_save) {
		mips32_pracc_write_mem32(ejtag_info, source->address, ARRAY_SIZE(handler_code), handler_code);
		/* save previous operation to speed to any consecutive read/writes */
		ejtag_info->fast_access_save = write_t;
	}

	LOG_DEBUG("%s using 0x%.8" PRIx32 " for write handler", __func__, source->address);

	jmp_code[1] |= UPPER16(source->address);
	jmp_code[2] |= LOWER16(source->address);

	for (i = 0; i < (int) ARRAY_SIZE(jmp_code); i++) {
		retval = wait_for_pracc_rw(ejtag_info, &ejtag_ctrl);
		if (retval != ERROR_OK)
			return retval;

		mips_ejtag_set_instr(ejtag_info, EJTAG_INST_DATA);
		mips_ejtag_drscan_32_out(ejtag_info, jmp_code[i]);

		/* Clear the access pending bit (let the processor eat!) */
		ejtag_ctrl = ejtag_info->ejtag_ctrl & ~EJTAG_CTRL_PRACC;
		mips_ejtag_set_instr(ejtag_info, EJTAG_INST_CONTROL);
		mips_ejtag_drscan_32_out(ejtag_info, ejtag_ctrl);
	}

	retval = wait_for_pracc_rw(ejtag_info, &ejtag_ctrl);
	if (retval != ERROR_OK)
		return retval;

	/* next fetch to dmseg should be in FASTDATA_AREA, check */
	address = 0;
	mips_ejtag_set_instr(ejtag_info, EJTAG_INST_ADDRESS);
	retval = mips_ejtag_drscan_32(ejtag_info, &address);
	if (retval != ERROR_OK)
		return retval;

	if (address != MIPS32_PRACC_FASTDATA_AREA)
		return ERROR_FAIL;

	/* wait PrAcc pending bit for FASTDATA write */
	retval = wait_for_pracc_rw(ejtag_info, &ejtag_ctrl);
	if (retval != ERROR_OK)
		return retval;

	/* Send the load start address */
	val = addr;
	mips_ejtag_set_instr(ejtag_info, EJTAG_INST_FASTDATA);
	mips_ejtag_fastdata_scan(ejtag_info, 1, &val);

	/* Send the load end address */
	val = addr + (count - 1) * 4;
	mips_ejtag_fastdata_scan(ejtag_info, 1, &val);

	for (i = 0; i < count; i++) {
		retval = mips_ejtag_fastdata_scan(ejtag_info, write_t, buf++);
		if (retval != ERROR_OK)
			return retval;
	}

	retval = jtag_execute_queue();
	if (retval != ERROR_OK) {
		LOG_ERROR("fastdata load failed");
		return retval;
	}

	retval = wait_for_pracc_rw(ejtag_info, &ejtag_ctrl);
	if (retval != ERROR_OK)
		return retval;

	address = 0;
	mips_ejtag_set_instr(ejtag_info, EJTAG_INST_ADDRESS);
	retval = mips_ejtag_drscan_32(ejtag_info, &address);
	if (retval != ERROR_OK)
		return retval;

	if (address != MIPS32_PRACC_TEXT)
		LOG_ERROR("mini program did not return to start");

	return retval;
}