jtag: basic support for P&E Micro OSBDM (aka OSJTAG) adapter

This driver provides support for the P&E Micro OSBDM adapter (sometimes
named as OSJTAG), mounted on the Freescale TWRK60N512 bord. Thus, it
provides a quick start when working with this board. The driver doesn't
use BDM commands, but work with OSBDM adapter using only JTAG commands.

Change-Id: Ibc3779538e666e07651d3136431e5d44344f3b07
Signed-off-by: Jan Dakinevich <jan.dakinevich@gmail.com>
Reviewed-on: http://openocd.zylin.com/492
Tested-by: jenkins
Reviewed-by: Tomas Frydrych <tf+openocd@r-finger.com>
Reviewed-by: Spencer Oliver <spen@spen-soft.co.uk>

6 files changed, 759 insertions, 3 deletions

diff --git a/configure.ac b/configure.ac
index ffab637..0b33712 100644
--- a/configure.ac
+++ b/configure.ac
@@ -478,6 +478,10 @@ AC_ARG_ENABLE([stlink],
   AS_HELP_STRING([--enable-stlink], [Enable building support for the ST-Link JTAG Programmer]),
   [build_stlink=$enableval], [build_stlink=no])
 
+AC_ARG_ENABLE([osbdm],
+  AS_HELP_STRING([--enable-osbdm], [Enable building support for the OSBDM (JTAG only) Programmer]),
+  [build_osbdm=$enableval], [build_osbdm=no])
+
 AC_ARG_ENABLE([minidriver_dummy],
   AS_HELP_STRING([--enable-minidriver-dummy], [Enable the dummy minidriver.]),
   [build_minidriver_dummy=$enableval], [build_minidriver_dummy=no])
@@ -783,6 +787,12 @@ else
   AC_DEFINE(BUILD_STLINK, 0, [0 if you don't want the ST-Link JTAG driver.])
 fi
 
+if test $build_osbdm = yes; then
+  AC_DEFINE(BUILD_OSBDM, 1, [1 if you want the OSBDM driver.])
+else
+  AC_DEFINE(BUILD_OSBDM, 0, [0 if you don't want the OSBDM driver.])
+fi
+
 if test "$use_internal_jimtcl" = yes; then
   if test -f "$srcdir/jimtcl/configure.ac"; then
     AX_CONFIG_SUBDIR_OPTION([jimtcl], [--disable-install-jim])
@@ -1069,7 +1079,7 @@ fi
 
 # Check for libusb1 ported drivers.
 build_usb_ng=no
-if test $build_jlink = yes -o $build_stlink = yes; then
+if test $build_jlink = yes -o $build_stlink = yes -o $build_osbdm = yes; then
   build_usb_ng=yes
 fi
 
@@ -1118,6 +1128,7 @@ AM_CONDITIONAL([ARMJTAGEW], [test $build_armjtagew = yes])
 AM_CONDITIONAL([REMOTE_BITBANG], [test $build_remote_bitbang = yes])
 AM_CONDITIONAL([BUSPIRATE], [test $build_buspirate = yes])
 AM_CONDITIONAL([STLINK], [test $build_stlink = yes])
+AM_CONDITIONAL([OSBDM], [test $build_osbdm = yes])
 AM_CONDITIONAL([USB], [test $build_usb = yes])
 AM_CONDITIONAL([USB_NG], [test $build_usb_ng = yes])
 AM_CONDITIONAL([USE_LIBUSB0], [test $use_libusb0 = yes])
diff --git a/src/jtag/drivers/Makefile.am b/src/jtag/drivers/Makefile.am
index 134323d..459027f 100644
--- a/src/jtag/drivers/Makefile.am
+++ b/src/jtag/drivers/Makefile.am
@@ -98,6 +98,9 @@ endif
 if STLINK
 DRIVERFILES += stlink_usb.c
 endif
+if OSBDM
+DRIVERFILES += osbdm.c
+endif
 
 noinst_HEADERS = \
 	bitbang.h \
diff --git a/src/jtag/drivers/osbdm.c b/src/jtag/drivers/osbdm.c
new file mode 100644
index 0000000..1875600
--- /dev/null
+++ b/src/jtag/drivers/osbdm.c
@@ -0,0 +1,722 @@
+/***************************************************************************
+ *   Copyright (C) 2012 by Jan Dakinevich                                  *
+ *   jan.dakinevich@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.             *
+ ***************************************************************************/
+#ifdef HAVE_CONFIG_H
+#	include "config.h"
+#endif
+
+#include <helper/log.h>
+#include <helper/binarybuffer.h>
+#include <helper/command.h>
+#include <jtag/interface.h>
+#include "libusb_common.h"
+
+struct sequence {
+	int len;
+	void *tms;
+	void *tdo;
+	const void *tdi;
+	struct sequence *next;
+};
+
+struct queue {
+	struct sequence *head;
+	struct sequence *tail;
+};
+
+static struct sequence *queue_add_tail(struct queue *queue, int len)
+{
+	if (len <= 0) {
+		LOG_ERROR("BUG: sequences with zero length are not allowed");
+		return NULL;
+	}
+
+	struct sequence *next;
+	next = (struct sequence *)malloc(sizeof(*next));
+	if (next) {
+		next->tms = calloc(1, DIV_ROUND_UP(len, 8));
+		if (next->tms) {
+			next->len = len;
+			next->tdo = NULL;
+			next->tdi = NULL;
+			next->next = NULL;
+
+			if (!queue->head) {
+				/* Queue is empty at the moment */
+				queue->head = next;
+			} else {
+				/* Queue already contains at least one sequence */
+				queue->tail->next = next;
+			}
+
+			queue->tail = next;
+		} else {
+			free(next);
+			next = NULL;
+		}
+	}
+
+	if (!next)
+		LOG_ERROR("Not enough memory");
+
+	return next;
+}
+
+static void queue_drop_head(struct queue *queue)
+{
+	struct sequence *head = queue->head->next; /* New head */
+	free(queue->head->tms);
+	free(queue->head);
+	queue->head = head;
+}
+
+static void queue_free(struct queue *queue)
+{
+	if (queue) {
+		while (queue->head)
+			queue_drop_head(queue);
+
+		free(queue);
+	}
+}
+
+static struct queue *queue_alloc(void)
+{
+	struct queue *queue = (struct queue *)malloc(sizeof(struct queue));
+	if (queue)
+		queue->head = NULL;
+	else
+		LOG_ERROR("Not enough memory");
+
+	return queue;
+}
+
+/* Size of usb communnication buffer */
+#define OSBDM_USB_BUFSIZE 64
+/* Timeout for USB transfer, ms */
+#define OSBDM_USB_TIMEOUT 1000
+/* Write end point */
+#define OSBDM_USB_EP_WRITE 0x01
+/* Read end point */
+#define OSBDM_USB_EP_READ 0x82
+
+/* Initialize OSBDM device */
+#define OSBDM_CMD_INIT 0x11
+/* Execute special, not-BDM command. But only this
+ * command is used for JTAG operation */
+#define OSBDM_CMD_SPECIAL 0x27
+/* Execute JTAG swap (tms/tdi -> tdo) */
+#define OSBDM_CMD_SPECIAL_SWAP 0x05
+/* Reset control */
+#define OSBDM_CMD_SPECIAL_SRST 0x01
+/* Maximum bit-length in one swap */
+#define OSBDM_SWAP_MAX (((OSBDM_USB_BUFSIZE - 6) / 5) * 16)
+
+/* Lists of valid VID/PID pairs
+ */
+static const uint16_t osbdm_vid[] = { 0x15a2, 0x15a2, 0 };
+static const uint16_t osbdm_pid[] = { 0x0042, 0x0058, 0 };
+
+struct osbdm {
+	struct jtag_libusb_device_handle *devh; /* USB handle */
+	uint8_t buffer[OSBDM_USB_BUFSIZE]; /* Data to send and recieved */
+	int count; /* Count data to send and to read */
+};
+
+/* osbdm instance
+ */
+static struct osbdm osbdm_context;
+
+static int osbdm_send_and_recv(struct osbdm *osbdm)
+{
+	/* Send request */
+	int count = jtag_libusb_bulk_write(osbdm->devh, OSBDM_USB_EP_WRITE,
+		(char *)osbdm->buffer, osbdm->count, OSBDM_USB_TIMEOUT);
+
+	if (count != osbdm->count) {
+		LOG_ERROR("OSBDM communnication error: can't write");
+		return ERROR_FAIL;
+	}
+
+	/* Save command code for next checking */
+	uint8_t cmd_saved = osbdm->buffer[0];
+
+	/* Reading answer */
+	osbdm->count = jtag_libusb_bulk_read(osbdm->devh, OSBDM_USB_EP_READ,
+		(char *)osbdm->buffer, OSBDM_USB_BUFSIZE, OSBDM_USB_TIMEOUT);
+
+	/* Now perform basic checks for data sent by BDM device
+	 */
+
+	if (osbdm->count < 0) {
+		LOG_ERROR("OSBDM communnication error: can't read");
+		return ERROR_FAIL;
+	}
+
+	if (osbdm->count < 2) {
+		LOG_ERROR("OSBDM communnication error: answer too small");
+		return ERROR_FAIL;
+	}
+
+	if (osbdm->count != osbdm->buffer[1])  {
+		LOG_ERROR("OSBDM communnication error: answer size mismatch");
+		return ERROR_FAIL;
+	}
+
+	if (cmd_saved != osbdm->buffer[0]) {
+		LOG_ERROR("OSBDM communnication error: answer command mismatch");
+		return ERROR_FAIL;
+	}
+
+	return ERROR_OK;
+}
+
+static int osbdm_srst(struct osbdm *osbdm, int srst)
+{
+	osbdm->count = 0;
+	(void)memset(osbdm->buffer, 0, OSBDM_USB_BUFSIZE);
+
+	/* Composing request
+	 */
+	osbdm->buffer[osbdm->count++] = OSBDM_CMD_SPECIAL; /* Command */
+	osbdm->buffer[osbdm->count++] = OSBDM_CMD_SPECIAL_SRST; /* Subcommand */
+	/* Length in bytes - not used */
+	osbdm->buffer[osbdm->count++] = 0;
+	osbdm->buffer[osbdm->count++] = 0;
+	/* SRST state */
+	osbdm->buffer[osbdm->count++] = (srst ? 0 : 0x08);
+
+	/* Sending data
+	 */
+	if (osbdm_send_and_recv(osbdm) != ERROR_OK)
+		return ERROR_FAIL;
+
+	return ERROR_OK;
+}
+
+static int osbdm_swap(struct osbdm *osbdm, void *tms, void *tdi,
+	void *tdo, int length)
+{
+	if (length > OSBDM_SWAP_MAX) {
+		LOG_ERROR("BUG: bit sequence too long");
+		return ERROR_FAIL;
+	}
+
+	if (length <= 0) {
+		LOG_ERROR("BUG: bit sequence equal or less to 0");
+		return ERROR_FAIL;
+	}
+
+	int swap_count = DIV_ROUND_UP(length, 16);
+
+	/* cleanup */
+	osbdm->count = 0;
+	(void)memset(osbdm->buffer, 0, OSBDM_USB_BUFSIZE);
+
+	/* Composing request
+	 */
+
+	osbdm->buffer[osbdm->count++] = OSBDM_CMD_SPECIAL; /* Command */
+	osbdm->buffer[osbdm->count++] = OSBDM_CMD_SPECIAL_SWAP; /* Subcommand */
+	/* Length in bytes - not used */
+	osbdm->buffer[osbdm->count++] = 0;
+	osbdm->buffer[osbdm->count++] = 0;
+	/* Swap count */
+	osbdm->buffer[osbdm->count++] = 0;
+	osbdm->buffer[osbdm->count++] = (uint8_t)swap_count;
+
+	for (int bit_idx = 0; bit_idx < length; ) {
+		/* Bit count in swap */
+		int bit_count = length - bit_idx;
+		if (bit_count > 16)
+			bit_count = 16;
+
+		osbdm->buffer[osbdm->count++] = (uint8_t)bit_count;
+
+		/* Copying TMS and TDI data to output buffer */
+		uint32_t tms_data = buf_get_u32(tms, bit_idx, bit_count);
+		uint32_t tdi_data = buf_get_u32(tdi, bit_idx, bit_count);
+		osbdm->buffer[osbdm->count++] = (uint8_t)(tdi_data >> 8);
+		osbdm->buffer[osbdm->count++] = (uint8_t)tdi_data;
+		osbdm->buffer[osbdm->count++] = (uint8_t)(tms_data >> 8);
+		osbdm->buffer[osbdm->count++] = (uint8_t)tms_data;
+
+		/* Next bit offset */
+		bit_idx += bit_count;
+	}
+
+	assert(osbdm->count <= OSBDM_USB_BUFSIZE);
+
+	/* Sending data
+	 */
+	if (osbdm_send_and_recv(osbdm) != ERROR_OK)
+		return ERROR_FAIL;
+
+	/*	Extra check
+	 */
+	if (((osbdm->buffer[2] << 8) | osbdm->buffer[3]) != 2 * swap_count) {
+		LOG_ERROR("OSBDM communnication error: not proper answer to swap command");
+		return ERROR_FAIL;
+	}
+
+	/* Copy TDO responce
+	 */
+	uint8_t *buffer = (uint8_t *)osbdm->buffer + 4;
+	for (int bit_idx = 0; bit_idx < length; ) {
+		int bit_count = length - bit_idx;
+		if (bit_count > 16)
+			bit_count = 16;
+
+		/* Prepare data */
+		uint32_t tdo_data = 0;
+		tdo_data |= (*buffer++) << 8;
+		tdo_data |= (*buffer++);
+		tdo_data >>= (16 - bit_count);
+
+		/* Copy TDO to return */
+		buf_set_u32(tdo, bit_idx, bit_count, tdo_data);
+
+		bit_idx += bit_count;
+	}
+
+	return ERROR_OK;
+}
+
+static int osbdm_flush(struct osbdm *osbdm, struct queue* queue)
+{
+	uint8_t tms[DIV_ROUND_UP(OSBDM_SWAP_MAX, 8)];
+	uint8_t tdi[DIV_ROUND_UP(OSBDM_SWAP_MAX, 8)];
+	uint8_t tdo[DIV_ROUND_UP(OSBDM_SWAP_MAX, 8)];
+
+	int seq_back_len = 0;
+
+	while (queue->head) {
+		(void)memset(tms, 0, sizeof(tms));
+		(void)memset(tdi, 0, sizeof(tdi));
+		(void)memset(tdo, 0, sizeof(tdo));
+
+		int seq_len;
+		int swap_len;
+		struct sequence *seq;
+
+		/* Copy from queue to tms/tdi streams
+		 */
+		seq = queue->head;
+		seq_len = seq_back_len;
+		swap_len = 0;
+
+		while (seq && swap_len != OSBDM_SWAP_MAX) {
+			/* Count bit for copy at this iteration.
+			 * len should fit into remaining space
+			 * in tms/tdo bitstreams
+			 */
+			int len = seq->len - seq_len;
+			if (len > OSBDM_SWAP_MAX - swap_len)
+				len = OSBDM_SWAP_MAX - swap_len;
+
+			/* Set tms data */
+			buf_set_buf(seq->tms, seq_len, tms, swap_len, len);
+
+			/* Set tdi data if they exists */
+			if (seq->tdi)
+				buf_set_buf(seq->tdi, seq_len, tdi, swap_len, len);
+
+			swap_len += len;
+			seq_len += len;
+			if (seq_len == seq->len) {
+				seq = seq->next; /* Move to next sequence */
+				seq_len = 0;
+			}
+		}
+
+		if (osbdm_swap(osbdm, tms, tdi, tdo, swap_len))
+			return ERROR_FAIL;
+
+		/* Copy from tdo stream to queue
+		 */
+
+		for (int swap_back_len = 0; swap_back_len < swap_len; ) {
+			int len = queue->head->len - seq_back_len;
+			if (len > swap_len - swap_back_len)
+				len = swap_len - swap_back_len;
+
+			if (queue->head->tdo)
+				buf_set_buf(tdo, swap_back_len,	queue->head->tdo, seq_back_len, len);
+
+			swap_back_len += len;
+			seq_back_len += len;
+			if (seq_back_len == queue->head->len) {
+				queue_drop_head(queue);
+				seq_back_len = 0;
+			}
+		}
+	}
+
+	return ERROR_OK;
+}
+
+/*	Basic operation for opening USB device */
+static int osbdm_open(struct osbdm *osbdm)
+{
+	(void)memset(osbdm, 0, sizeof(*osbdm));
+	if (jtag_libusb_open(osbdm_vid, osbdm_pid, &osbdm->devh) != ERROR_OK)
+		return ERROR_FAIL;
+
+	if (jtag_libusb_claim_interface(osbdm->devh, 0) != ERROR_OK)
+		return ERROR_FAIL;
+
+	return ERROR_OK;
+}
+
+static int osbdm_quit(void)
+{
+	jtag_libusb_close(osbdm_context.devh);
+	return ERROR_OK;
+}
+
+static int osbdm_add_pathmove(
+	struct queue *queue,
+	tap_state_t *path,
+	int num_states)
+{
+	assert(num_states <= 32);
+
+	struct sequence *next = queue_add_tail(queue, num_states);
+	if (!next) {
+		LOG_ERROR("BUG: can't allocate bit sequence");
+		return ERROR_FAIL;
+	}
+
+	uint32_t tms = 0;
+	for (int i = 0; i < num_states; i++) {
+		if (tap_state_transition(tap_get_state(), 1) == path[i]) {
+			tms |= (1 << i);
+		} else if (tap_state_transition(tap_get_state(), 0) == path[i]) {
+			tms &= ~(1 << i); /* This line not so needed */
+		} else {
+			LOG_ERROR("BUG: %s -> %s isn't a valid TAP state transition",
+				tap_state_name(tap_get_state()),
+				tap_state_name(path[i]));
+			return ERROR_FAIL;
+		}
+
+		tap_set_state(path[i]);
+	}
+
+	buf_set_u32(next->tms, 0, num_states, tms);
+	tap_set_end_state(tap_get_state());
+
+	return ERROR_OK;
+}
+
+static int osbdm_add_statemove(
+	struct queue *queue,
+	tap_state_t new_state,
+	int skip_first)
+{
+	int len = 0;
+	int tms;
+
+	tap_set_end_state(new_state);
+	if (tap_get_end_state() == TAP_RESET) {
+		/* Ignore current state */
+		tms = 0xff;
+		len = 5;
+	} else if (tap_get_state() != tap_get_end_state()) {
+		tms = tap_get_tms_path(tap_get_state(), new_state);
+		len = tap_get_tms_path_len(tap_get_state(), new_state);
+	}
+
+	if (len && skip_first) {
+		len--;
+		tms >>= 1;
+	}
+
+	if (len) {
+		struct sequence *next = queue_add_tail(queue, len);
+		if (!next) {
+			LOG_ERROR("BUG: can't allocate bit sequence");
+			return ERROR_FAIL;
+		}
+		buf_set_u32(next->tms, 0, len, tms);
+	}
+
+	tap_set_state(tap_get_end_state());
+	return ERROR_OK;
+}
+
+static int osbdm_add_stableclocks(
+	struct queue *queue,
+	int count)
+{
+	if (!tap_is_state_stable(tap_get_state())) {
+		LOG_ERROR("BUG: current state (%s) is not stable",
+			tap_state_name(tap_get_state()));
+		return ERROR_FAIL;
+	}
+
+	struct sequence *next = queue_add_tail(queue, count);
+	if (!next) {
+		LOG_ERROR("BUG: can't allocate bit sequence");
+		return ERROR_FAIL;
+	}
+
+	if (tap_get_state() == TAP_RESET)
+		(void)memset(next->tms, 0xff, DIV_ROUND_UP(count, 8));
+
+	return ERROR_OK;
+}
+
+static int osbdm_add_tms(
+	struct queue *queue,
+	const uint8_t *tms,
+	int num_bits)
+{
+	struct sequence *next = queue_add_tail(queue, num_bits);
+	if (!next) {
+		LOG_ERROR("BUG: can't allocate bit sequence");
+		return ERROR_FAIL;
+	}
+	buf_set_buf(tms, 0, next->tms, 0, num_bits);
+
+	return ERROR_OK;
+}
+
+static int osbdm_add_scan(
+	struct queue *queue,
+	struct scan_field *fields,
+	int num_fields,
+	tap_state_t end_state,
+	bool ir_scan)
+{
+	/* Move to desired shift state */
+	if (ir_scan) {
+		if (tap_get_state() != TAP_IRSHIFT) {
+			if (osbdm_add_statemove(queue, TAP_IRSHIFT, 0) != ERROR_OK)
+				return ERROR_FAIL;
+		}
+	} else {
+		if (tap_get_state() != TAP_DRSHIFT) {
+			if (osbdm_add_statemove(queue, TAP_DRSHIFT, 0) != ERROR_OK)
+				return ERROR_FAIL;
+		}
+	}
+
+	/* Add scan */
+	tap_set_end_state(end_state);
+	for (int idx = 0; idx < num_fields; idx++) {
+		struct sequence *next = queue_add_tail(queue, fields[idx].num_bits);
+		if (!next) {
+			LOG_ERROR("Can't allocate bit sequence");
+			return ERROR_FAIL;
+		}
+
+		(void)memset(next->tms, 0, DIV_ROUND_UP(fields[idx].num_bits, 8));
+		next->tdi = fields[idx].out_value;
+		next->tdo = fields[idx].in_value;
+	}
+
+	/* Move to end state
+	 */
+	if (tap_get_state() != tap_get_end_state()) {
+		/* Exit from IRSHIFT/DRSHIFT */
+		buf_set_u32(queue->tail->tms, queue->tail->len - 1, 1, 1);
+
+		/* Move with skip_first flag */
+		if (osbdm_add_statemove(queue, tap_get_end_state(), 1) != ERROR_OK)
+			return ERROR_FAIL;
+	}
+
+	return ERROR_OK;
+}
+
+static int osbdm_add_runtest(
+	struct queue *queue,
+	int num_cycles,
+	tap_state_t end_state)
+{
+	if (osbdm_add_statemove(queue, TAP_IDLE, 0) != ERROR_OK)
+		return ERROR_FAIL;
+
+	if (osbdm_add_stableclocks(queue, num_cycles) != ERROR_OK)
+		return ERROR_FAIL;
+
+	if (osbdm_add_statemove(queue, end_state, 0) != ERROR_OK)
+		return ERROR_FAIL;
+
+	return ERROR_OK;
+}
+
+static int osbdm_execute_command(
+	struct osbdm *osbdm,
+	struct queue *queue,
+	struct jtag_command *cmd)
+{
+	int retval = ERROR_OK;
+
+	switch (cmd->type) {
+	case JTAG_RESET:
+		if (cmd->cmd.reset->trst) {
+			LOG_ERROR("BUG: nTRST signal is not supported");
+			retval = ERROR_FAIL;
+		} else {
+			retval = osbdm_flush(osbdm, queue);
+			if (retval == ERROR_OK)
+				retval = osbdm_srst(osbdm, cmd->cmd.reset->srst);
+		}
+		break;
+
+	case JTAG_PATHMOVE:
+		retval = osbdm_add_pathmove(
+			queue,
+			cmd->cmd.pathmove->path,
+			cmd->cmd.pathmove->num_states);
+		break;
+
+	case JTAG_TLR_RESET:
+		retval = osbdm_add_statemove(
+			queue,
+			cmd->cmd.statemove->end_state,
+			0);
+		break;
+
+	case JTAG_STABLECLOCKS:
+		retval = osbdm_add_stableclocks(
+			queue,
+			cmd->cmd.stableclocks->num_cycles);
+		break;
+
+	case JTAG_TMS:
+		retval = osbdm_add_tms(
+			queue,
+			cmd->cmd.tms->bits,
+			cmd->cmd.tms->num_bits);
+		break;
+
+	case JTAG_SCAN:
+		retval = osbdm_add_scan(
+			queue,
+			cmd->cmd.scan->fields,
+			cmd->cmd.scan->num_fields,
+			cmd->cmd.scan->end_state,
+			cmd->cmd.scan->ir_scan);
+		break;
+
+	case JTAG_SLEEP:
+		retval = osbdm_flush(osbdm, queue);
+		if (retval == ERROR_OK)
+			jtag_sleep(cmd->cmd.sleep->us);
+		break;
+
+	case JTAG_RUNTEST:
+		retval = osbdm_add_runtest(
+			queue,
+			cmd->cmd.runtest->num_cycles,
+			cmd->cmd.runtest->end_state);
+		break;
+
+	default:
+		LOG_ERROR("BUG: unknown JTAG command type encountered");
+		retval = ERROR_FAIL;
+		break;
+	}
+
+	return retval;
+}
+
+static int osbdm_execute_queue(void)
+{
+	int retval = ERROR_OK;
+
+	struct queue *queue = queue_alloc();
+	if (!queue) {
+		LOG_ERROR("BUG: can't allocate bit queue");
+		retval = ERROR_FAIL;
+	} else {
+		struct jtag_command *cmd = jtag_command_queue;
+
+		while (retval == ERROR_OK && cmd) {
+			retval = osbdm_execute_command(&osbdm_context, queue, cmd);
+			cmd = cmd->next;
+		}
+
+		if (retval == ERROR_OK)
+			retval = osbdm_flush(&osbdm_context, queue);
+
+		queue_free(queue);
+	}
+
+	if (retval != ERROR_OK) {
+		LOG_ERROR("FATAL: can't execute jtag command");
+		exit(-1);
+	}
+
+	return retval;
+}
+
+static int osbdm_init(void)
+{
+	/* Open device */
+	if (osbdm_open(&osbdm_context) != ERROR_OK) {
+		LOG_ERROR("Can't open OSBDM device");
+		return ERROR_FAIL;
+	} else {
+		/* Device successfully opened */
+		LOG_INFO("OSBDM has opened");
+	}
+
+	/* Perform initialize command */
+	osbdm_context.count = 0;
+	osbdm_context.buffer[osbdm_context.count++] = OSBDM_CMD_INIT;
+	if (osbdm_send_and_recv(&osbdm_context) != ERROR_OK)
+		return ERROR_FAIL;
+
+	return ERROR_OK;
+}
+
+static int osbdm_khz(int khz, int *speed)
+{
+	*speed = khz;
+	return ERROR_OK;
+}
+
+static int osbdm_speed(int speed)
+{
+	return ERROR_OK;
+}
+
+static int osbdm_speed_div(int speed, int *khz)
+{
+	*khz = speed;
+	return ERROR_OK;
+}
+
+struct jtag_interface osbdm_interface = {
+	.name = "osbdm",
+
+	.transports = jtag_only,
+	.execute_queue = osbdm_execute_queue,
+
+	.khz = osbdm_khz,
+	.speed = osbdm_speed,
+	.speed_div = osbdm_speed_div,
+
+	.init = osbdm_init,
+	.quit = osbdm_quit
+};
diff --git a/src/jtag/interfaces.c b/src/jtag/interfaces.c
index 304dab6..4937adb 100644
--- a/src/jtag/interfaces.c
+++ b/src/jtag/interfaces.c
@@ -104,6 +104,9 @@ extern struct jtag_interface remote_bitbang_interface;
 #if BUILD_STLINK == 1
 extern struct jtag_interface stlink_interface;
 #endif
+#if BUILD_OSBDM == 1
+extern struct jtag_interface osbdm_interface;
+#endif
 #endif /* standard drivers */
 
 /**
@@ -176,6 +179,9 @@ struct jtag_interface *jtag_interfaces[] = {
 #if BUILD_STLINK == 1
 		&stlink_interface,
 #endif
+#if BUILD_OSBDM == 1
+		&osbdm_interface,
+#endif
 #endif /* standard drivers */
 		NULL,
 	};
diff --git a/tcl/board/twr-k60n512.cfg b/tcl/board/twr-k60n512.cfg
index 00cf042..4fe35bb 100644
--- a/tcl/board/twr-k60n512.cfg
+++ b/tcl/board/twr-k60n512.cfg
@@ -1,10 +1,12 @@
 #
-# Freescale KwikStik development board
+# Freescale TWRK60N512 development board
 #
 
 source [find target/k60.cfg]
 
-reset_config trst_and_srst
+$_TARGETNAME configure -event reset-init {
+	puts "-event reset-init occured"
+}
 
 #
 # Bank definition for the 'program flash' (instructions and/or data)
diff --git a/tcl/interface/osbdm.cfg b/tcl/interface/osbdm.cfg
new file mode 100644
index 0000000..4d0c79d
--- /dev/null
+++ b/tcl/interface/osbdm.cfg
@@ -0,0 +1,12 @@
+#
+# P&E Micro OSBDM (aka OSJTAG) interface
+#
+# http://pemicro.com/osbdm/
+#
+interface osbdm
+reset_config srst_only
+
+#
+# OSBDM doesn't support speed control
+#
+adapter_khz 1