rpjtag.c

/*
 * Raspberry Pi JTAG Programmer using GPIO connector
 * Version 0.3 Copyright 2013 Rune 'Krelian' Joergensen
 *
 * 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 <stdlib.h>
#include <stdint.h>

#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include "rpjtag.h"    //Defines
#include "rpjtag_io.h" //Basic IO functions
#include "rpjtag_stateMachine.h"
#include "rpjtag_bit_reader.h"

int CountDevices()
{
	int tIRLen = 0;
	SelectShiftIR();

	for(x=0;x<MAX_CHAIN;x++) send_cmd(1,0); //Flush IR Registers, makes sure counting IR-Reg Size is currect
	
	for(i=0;i<MAX_CHAIN;i++)
	{
        x = read_jtag_tdo();
		send_cmd(0,0);
		if(!x) break;
		tIRLen++;
	}

    fprintf(stdout,"IR size from jtag: %d\n",tIRLen);

	for(x=0;x<MAX_CHAIN;x++) send_cmd(1,0); //PUT all in BYPASS
    send_cmd(1,1);
	ExitShift(); // state returns to IDLE

	SelectShiftDR();

	for(x=0;x<MAX_CHAIN;x++) send_cmd(0,0); //Flush DR register, used during debug

	for(x=0;x<tIRLen+1;x++) //put in 1's into DR, when TDO outputs a 1, end is reached
	{
		i = read_jtag_tdo();
		send_cmd(1,0);
		if(i) break;
	}

	if(x==tIRLen+1) x = 0; //if x reaches max an error occured

    syncJTAGs();
	return x;
}

//Raspberry PI side.
void help()
{
	fprintf(stderr,
	"Usage: rpjtag [options]\n"
	"   -h      Print help\n"
	"   -i	    Specify bit file (default = 'top.bit')\n"
	"\n");
    exit(0);
}


int main(int argc, char *argv[])
{
	char *ifile  = "top.bit";
	int opt;
	nDevices = 0;
	parms = 0;
	IRTotalRegSize = 0;
	jtag_state = 0x00;
	
	fprintf(stderr, "Raspberry Pi JTAG Programmer, v0.3 (April 2013)\n\n");

	while ((opt = getopt(argc, argv, "hi:")) != -1) {
		switch (opt) {
		case 'h':
			help();
			break;
		case 'i':
			ifile = optarg;
			break;
		default:
			fprintf(stderr, "\n");
			help();
			exit(0);
			break;
		}
	}

	if(ifile == 0x00)
		exit(0);

	FILE* bitstream = load_bit_file(ifile);

	// Set up gpi pointer for direct register access
    fprintf(stdout, "setting up IO\n");
	setup_io();

	//rpjtag_stateMachine.c
    fprintf(stdout, "sync-ing JTAG\n");
	syncJTAGs(); //Puts all JTAG Devices in RESET MODE
	
    fprintf(stdout, "Counting devices\n");
	nDevices = CountDevices(); //Count Number of devices, also finds total IR size
    fprintf(stdout,"Devices found: %d\n", nDevices);

    if (nDevices != 1)
    {
        fprintf(stderr, "nDevices > 1, add some code so I know what to do!");
    }

	if(nDevices != 0)
	{
		//rpjtag_bit_reader.c
		ProgramDevice(0,bitstream); 
	}
	fclose(bitstream);

    close_io();
	printf("\nDone\n");
	exit(0);
}