path: root/src/jtag/drivers/buspirate.c

/***************************************************************************
 *   Copyright (C) 2010 by Michal Demin                                    *
 *   based on usbprog.c and arm-jtag-ew.c                                  *
 *   Several fixes by R. Diez in 2013.                                     *
 *                                                                         *
 *   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.,                                       *
 *   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.           *
 ***************************************************************************/

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

#include <jtag/interface.h>
#include <jtag/commands.h>

#include <termios.h>
#include <fcntl.h>
#include <sys/ioctl.h>

#undef DEBUG_SERIAL
/*#define DEBUG_SERIAL */
static int buspirate_execute_queue(void);
static int buspirate_init(void);
static int buspirate_quit(void);

static void buspirate_end_state(tap_state_t state);
static void buspirate_state_move(void);
static void buspirate_path_move(int num_states, tap_state_t *path);
static void buspirate_runtest(int num_cycles);
static void buspirate_scan(bool ir_scan, enum scan_type type,
	uint8_t *buffer, int scan_size, struct scan_command *command);

#define CMD_UNKNOWN       0x00
#define CMD_PORT_MODE     0x01
#define CMD_FEATURE       0x02
#define CMD_READ_ADCS     0x03
/*#define CMD_TAP_SHIFT     0x04 // old protocol */
#define CMD_TAP_SHIFT     0x05
#define CMD_ENTER_OOCD    0x06
#define CMD_UART_SPEED    0x07
#define CMD_JTAG_SPEED    0x08

/* Not all OSes have this speed defined */
#if !defined(B1000000)
#define  B1000000 0010010
#endif

enum {
	MODE_HIZ = 0,
	MODE_JTAG = 1,		/* push-pull outputs */
	MODE_JTAG_OD = 2,	/* open-drain outputs */
};

enum {
	FEATURE_LED = 0x01,
	FEATURE_VREG = 0x02,
	FEATURE_TRST = 0x04,
	FEATURE_SRST = 0x08,
	FEATURE_PULLUP = 0x10
};

enum {
	ACTION_DISABLE = 0,
	ACTION_ENABLE = 1
};

enum {
	SERIAL_NORMAL = 0,
	SERIAL_FAST = 1
};

static const cc_t SHORT_TIMEOUT  = 1; /* Must be at least 1. */
static const cc_t NORMAL_TIMEOUT = 10;

static int buspirate_fd = -1;
static int buspirate_pinmode = MODE_JTAG_OD;
static int buspirate_baudrate = SERIAL_NORMAL;
static int buspirate_vreg;
static int buspirate_pullup;
static char *buspirate_port;

static enum tap_state last_tap_state = TAP_RESET;


/* TAP interface */
static void buspirate_tap_init(void);
static int buspirate_tap_execute(void);
static void buspirate_tap_append(int tms, int tdi);
static void buspirate_tap_append_scan(int length, uint8_t *buffer,
		struct scan_command *command);
static void buspirate_tap_make_space(int scan, int bits);

static void buspirate_reset(int trst, int srst);

/* low level interface */
static void buspirate_jtag_reset(int);
static void buspirate_jtag_enable(int);
static unsigned char buspirate_jtag_command(int, char *, int);
static void buspirate_jtag_set_speed(int, char);
static void buspirate_jtag_set_mode(int, char);
static void buspirate_jtag_set_feature(int, char, char);
static void buspirate_jtag_get_adcs(int);

/* low level HW communication interface */
static int buspirate_serial_open(char *port);
static int buspirate_serial_setspeed(int fd, char speed, cc_t timeout);
static int buspirate_serial_write(int fd, char *buf, int size);
static int buspirate_serial_read(int fd, char *buf, int size);
static void buspirate_serial_close(int fd);
static void buspirate_print_buffer(char *buf, int size);

static int buspirate_execute_queue(void)
{