move jtag drivers to src/jtag/drivers

Moves JTAG interface drivers to src/jtag/drivers/,
Adds src/jtag/drivers/Makefile.am.
Builds libocdjtagdrivers.la.

Flattens the rlink driver files into the drivers/ directory, adding
the 'rlink_' prefix or '.rlink' suffix as appropriate.

1 files changed, 0 insertions, 1085 deletions

diff --git a/src/jtag/jlink.c b/src/jtag/jlink.c
deleted file mode 100644
index 9b2326bd..00000000
--- a/src/jtag/jlink.c
+++ /dev/null
@@ -1,1085 +0,0 @@
-/***************************************************************************
- *   Copyright (C) 2007 by Juergen Stuber <juergen@jstuber.net>            *
- *   based on Dominic Rath's and Benedikt Sauter's usbprog.c               *
- *                                                                         *
- *   Copyright (C) 2008 by Spencer Oliver                                  *
- *   spen@spen-soft.co.uk                                                  *
- *                                                                         *
- *   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 "interface.h"
-#include "commands.h"
-#include "usb_common.h"
-
-
-#define VID 0x1366
-#define PID 0x0101
-
-#define JLINK_WRITE_ENDPOINT	0x02
-#define JLINK_READ_ENDPOINT		0x81
-
-static unsigned int jlink_write_ep = JLINK_WRITE_ENDPOINT;
-static unsigned int jlink_read_ep = JLINK_READ_ENDPOINT;
-static unsigned int jlink_hw_jtag_version = 2;
-
-#define JLINK_USB_TIMEOUT		1000
-
-// See Section 1.3.2 of the Segger JLink USB protocol manual
-/* 2048 is the max value we can use here */
-//#define JLINK_TAP_BUFFER_SIZE 2048
-#define JLINK_TAP_BUFFER_SIZE 256
-//#define JLINK_TAP_BUFFER_SIZE 384
-
-#define JLINK_IN_BUFFER_SIZE			2048
-#define JLINK_OUT_BUFFER_SIZE			2*2048 + 4
-#define JLINK_EMU_RESULT_BUFFER_SIZE	64
-
-/* Global USB buffers */
-static uint8_t usb_in_buffer[JLINK_IN_BUFFER_SIZE];
-static uint8_t usb_out_buffer[JLINK_OUT_BUFFER_SIZE];
-static uint8_t usb_emu_result_buffer[JLINK_EMU_RESULT_BUFFER_SIZE];
-
-/* Constants for JLink command */
-#define EMU_CMD_VERSION		0x01
-#define EMU_CMD_SET_SPEED		0x05
-#define EMU_CMD_GET_STATE		0x07
-#define EMU_CMD_HW_CLOCK			0xc8
-#define EMU_CMD_HW_TMS0			0xc9
-#define EMU_CMD_HW_TMS1			0xca
-#define EMU_CMD_HW_JTAG2		0xce
-#define EMU_CMD_HW_JTAG3		0xcf
-#define EMU_CMD_GET_MAX_MEM_BLOCK	0xd4
-#define EMU_CMD_HW_RESET0		0xdc
-#define EMU_CMD_HW_RESET1		0xdd
-#define EMU_CMD_HW_TRST0		0xde
-#define EMU_CMD_HW_TRST1		0xdf
-#define EMU_CMD_GET_CAPS		0xe8
-#define EMU_CMD_GET_HW_VERSION	0xf0
-
-/* bits return from EMU_CMD_GET_CAPS */
-#define EMU_CAP_GET_HW_VERSION		1
-#define EMU_CAP_GET_MAX_BLOCK_SIZE	11
-
-/* max speed 12MHz v5.0 jlink */
-#define JLINK_MAX_SPEED 12000
-
-/* Queue command functions */
-static void jlink_end_state(tap_state_t state);
-static void jlink_state_move(void);
-static void jlink_path_move(int num_states, tap_state_t *path);
-static void jlink_runtest(int num_cycles);
-static void jlink_scan(bool ir_scan, enum scan_type type, uint8_t *buffer, int scan_size, struct scan_command *command);
-static void jlink_reset(int trst, int srst);
-static void jlink_simple_command(uint8_t command);
-static int jlink_get_status(void);
-
-/* J-Link tap buffer functions */
-static void jlink_tap_init(void);
-static int jlink_tap_execute(void);
-static void jlink_tap_ensure_space(int scans, int bits);
-static void jlink_tap_append_step(int tms, int tdi);
-static void jlink_tap_append_scan(int length, uint8_t *buffer, struct scan_command *command);
-
-/* Jlink lowlevel functions */
-struct jlink {
-	struct usb_dev_handle* usb_handle;
-};
-
-static struct jlink *jlink_usb_open(void);
-static void jlink_usb_close(struct jlink *jlink);
-static int jlink_usb_message(struct jlink *jlink, int out_length, int in_length);
-static int jlink_usb_write(struct jlink *jlink, int out_length);
-static int jlink_usb_read(struct jlink *jlink, int expected_size);
-static int jlink_usb_read_emu_result(struct jlink *jlink);
-
-/* helper functions */
-static int jlink_get_version_info(void);
-
-#ifdef _DEBUG_USB_COMMS_
-static void jlink_debug_buffer(uint8_t *buffer, int length);
-#endif
-
-static enum tap_state jlink_last_state = TAP_RESET;
-
-static struct jlink* jlink_handle;
-
-/***************************************************************************/
-/* External interface implementation */
-
-static void jlink_execute_runtest(struct jtag_command *cmd)
-{
-	DEBUG_JTAG_IO("runtest %i cycles, end in %i",
-			cmd->cmd.runtest->num_cycles,
-			cmd->cmd.runtest->end_state);
-
-	jlink_end_state(cmd->cmd.runtest->end_state);
-
-	jlink_runtest(cmd->cmd.runtest->num_cycles);
-}
-
-static void jlink_execute_statemove(struct jtag_command *cmd)
-{
-	DEBUG_JTAG_IO("statemove end in %i", cmd->cmd.statemove->end_state);
-
-	jlink_end_state(cmd->cmd.statemove->end_state);
-	jlink_state_move();
-}
-
-static void jlink_execute_pathmove(struct jtag_command *cmd)
-{
-	DEBUG_JTAG_IO("pathmove: %i states, end in %i",
-		cmd->cmd.pathmove->num_states,
-		cmd->cmd.pathmove->path[cmd->cmd.pathmove->num_states - 1]);
-
-	jlink_path_move(cmd->cmd.pathmove->num_states,
-			cmd->cmd.pathmove->path);
-}
-
-static void jlink_execute_scan(struct jtag_command *cmd)
-{
-	int scan_size;
-	enum scan_type type;
-	uint8_t *buffer;
-
-	DEBUG_JTAG_IO("scan end in %s", tap_state_name(cmd->cmd.scan->end_state));
-
-	jlink_end_state(cmd->cmd.scan->end_state);
-
-	scan_size = jtag_build_buffer(cmd->cmd.scan, &buffer);
-	DEBUG_JTAG_IO("scan input, length = %d", scan_size);
-
-#ifdef _DEBUG_USB_COMMS_
-	jlink_debug_buffer(buffer, (scan_size + 7) / 8);
-#endif
-	type = jtag_scan_type(cmd->cmd.scan);
-	jlink_scan(cmd->cmd.scan->ir_scan,
-			type, buffer, scan_size, cmd->cmd.scan);
-}
-
-static void jlink_execute_reset(struct jtag_command *cmd)
-{
-	DEBUG_JTAG_IO("reset trst: %i srst %i",
-			cmd->cmd.reset->trst, cmd->cmd.reset->srst);
-
-	jlink_tap_execute();
-	jlink_reset(cmd->cmd.reset->trst, cmd->cmd.reset->srst);
-	jlink_tap_execute();
-}
-
-static void jlink_execute_sleep(struct jtag_command *cmd)
-{
-	DEBUG_JTAG_IO("sleep %i", cmd->cmd.sleep->us);
-	jlink_tap_execute();
-	jtag_sleep(cmd->cmd.sleep->us);
-}
-
-static void jlink_execute_command(struct jtag_command *cmd)
-{
-	switch (cmd->type)
-	{
-	case JTAG_RUNTEST:   jlink_execute_runtest(cmd); break;
-	case JTAG_STATEMOVE: jlink_execute_statemove(cmd); break;
-	case JTAG_PATHMOVE:  jlink_execute_pathmove(cmd); break;
-	case JTAG_SCAN:      jlink_execute_scan(cmd); break;
-	case JTAG_RESET:     jlink_execute_reset(cmd); break;
-	case JTAG_SLEEP:     jlink_execute_sleep(cmd); break;
-	default:
-		LOG_ERROR("BUG: unknown JTAG command type encountered");
-		exit(-1);
-	}
-}
-
-static int jlink_execute_queue(void)
-{
-	struct jtag_command *cmd = jtag_command_queue;
-
-	while (cmd != NULL)
-	{
-		jlink_execute_command(cmd);
-		cmd = cmd->next;
-	}
-
-	return jlink_tap_execute();
-}
-
-/* Sets speed in kHz. */
-static int jlink_speed(int speed)
-{
-	int result;
-
-	if (speed > JLINK_MAX_SPEED)
-	{
-		LOG_INFO("Ignoring speed request: %dkHz exceeds %dkHz maximum",
-				speed, JLINK_MAX_SPEED);
-		return ERROR_OK;
-	}
-
-	/* check for RTCK setting */
-	if (speed == 0)
-		speed = -1;
-
-	usb_out_buffer[0] = EMU_CMD_SET_SPEED;
-	usb_out_buffer[1] = (speed >> 0) & 0xff;
-	usb_out_buffer[2] = (speed >> 8) & 0xff;
-
-	result = jlink_usb_write(jlink_handle, 3);
-	if (result != 3)
-	{
-		LOG_ERROR("J-Link setting speed failed (%d)", result);
-		return ERROR_JTAG_DEVICE_ERROR;
-	}
-
-	return ERROR_OK;
-}
-
-static int jlink_speed_div(int speed, int* khz)
-{
-	*khz = speed;
-
-	return ERROR_OK;
-}
-
-static int jlink_khz(int khz, int *jtag_speed)
-{
-	*jtag_speed = khz;
-
-	return ERROR_OK;
-}
-
-static int jlink_init(void)
-{
-	int i;
-
-	jlink_handle = jlink_usb_open();
-
-	if (jlink_handle == 0)
-	{
-		LOG_ERROR("Cannot find jlink Interface! Please check connection and permissions.");
-		return ERROR_JTAG_INIT_FAILED;
-	}
-
-	/*
-	 *  The next three instructions were added after discovering a problem while using an oscilloscope.  For the V8
-	 *	SAM-ICE dongle (and likely other j-link device variants), the reset line to the target microprocessor was found to
-	 *	cycle only intermittently during emulator startup (even after encountering the downstream reset instruction later
-	 *	in the code).  This was found to create two issues:  1) In general it is a bad practice to not reset a CPU to a known
-	 *	state when starting an emulator and 2) something critical happens inside the dongle when it does the first read
-	 *	following a new USB session.  Keeping the processor in reset during the first read collecting version information
-	 *	seems to prevent errant "J-Link command EMU_CMD_VERSION failed" issues.
-	 */
-
-	LOG_INFO("J-Link initialization started / target CPU reset initiated");
-	jlink_simple_command(EMU_CMD_HW_TRST0);
-	jlink_simple_command(EMU_CMD_HW_RESET0);
-	usleep(1000);
-
-	jlink_hw_jtag_version = 2;
-
-	if (jlink_get_version_info() == ERROR_OK)
-	{
-		/* attempt to get status */
-		jlink_get_status();
-	}
-
-	LOG_INFO("J-Link JTAG Interface ready");
-
-	jlink_reset(0, 0);
-	jtag_sleep(3000);
-	jlink_tap_init();
-	jlink_speed(jtag_get_speed());
-
-	/* v5/6 jlink seems to have an issue if the first tap move
-	 * is not divisible by 8, so we send a TLR on first power up */
-	for (i = 0; i < 8; i++) {
-		jlink_tap_append_step(1, 0);
-	}
-	jlink_tap_execute();
-
-	return ERROR_OK;
-}
-
-static int jlink_quit(void)
-{
-	jlink_usb_close(jlink_handle);
-	return ERROR_OK;
-}
-
-/***************************************************************************/
-/* Queue command implementations */
-
-static void jlink_end_state(tap_state_t state)
-{
-	if (tap_is_state_stable(state))
-	{
-		tap_set_end_state(state);
-	}
-	else
-	{
-		LOG_ERROR("BUG: %i is not a valid end state", state);
-		exit(-1);
-	}
-}
-
-/* Goes to the end state. */
-static void jlink_state_move(void)
-{
-	int i;
-	int tms = 0;
-	uint8_t tms_scan = tap_get_tms_path(tap_get_state(), tap_get_end_state());
-	uint8_t tms_scan_bits = tap_get_tms_path_len(tap_get_state(), tap_get_end_state());
-
-	for (i = 0; i < tms_scan_bits; i++)
-	{
-		tms = (tms_scan >> i) & 1;
-		jlink_tap_append_step(tms, 0);
-	}
-
-	tap_set_state(tap_get_end_state());
-}
-
-static void jlink_path_move(int num_states, tap_state_t *path)
-{
-	int i;
-
-	for (i = 0; i < num_states; i++)
-	{
-		if (path[i] == tap_state_transition(tap_get_state(), false))
-		{
-			jlink_tap_append_step(0, 0);
-		}
-		else if (path[i] == tap_state_transition(tap_get_state(), true))
-		{
-			jlink_tap_append_step(1, 0);
-		}
-		else
-		{
-			LOG_ERROR("BUG: %s -> %s isn't a valid TAP transition", tap_state_name(tap_get_state()), tap_state_name(path[i]));
-			exit(-1);
-		}
-
-		tap_set_state(path[i]);
-	}
-
-	tap_set_end_state(tap_get_state());
-}
-
-static void jlink_runtest(int num_cycles)
-{
-	int i;
-
-	tap_state_t saved_end_state = tap_get_end_state();
-
-	jlink_tap_ensure_space(1,num_cycles + 16);
-
-	/* only do a state_move when we're not already in IDLE */
-	if (tap_get_state() != TAP_IDLE)
-	{
-		jlink_end_state(TAP_IDLE);
-		jlink_state_move();
-//		num_cycles--;
-	}
-
-	/* execute num_cycles */
-	for (i = 0; i < num_cycles; i++)
-	{
-		jlink_tap_append_step(0, 0);
-	}
-
-	/* finish in end_state */
-	jlink_end_state(saved_end_state);
-	if (tap_get_state() != tap_get_end_state())
-	{
-		jlink_state_move();
-	}
-}
-
-static void jlink_scan(bool ir_scan, enum scan_type type, uint8_t *buffer, int scan_size, struct scan_command *command)
-{
-	tap_state_t saved_end_state;
-
-	jlink_tap_ensure_space(1, scan_size + 16);
-
-	saved_end_state = tap_get_end_state();
-
-	/* Move to appropriate scan state */
-	jlink_end_state(ir_scan ? TAP_IRSHIFT : TAP_DRSHIFT);
-
-	/* Only move if we're not already there */
-	if (tap_get_state() != tap_get_end_state())
-		jlink_state_move();
-
-	jlink_end_state(saved_end_state);
-
-	/* Scan */
-	jlink_tap_append_scan(scan_size, buffer, command);
-
-	/* We are in Exit1, go to Pause */
-	jlink_tap_append_step(0, 0);
-
-	tap_set_state(ir_scan ? TAP_IRPAUSE : TAP_DRPAUSE);
-
-	if (tap_get_state() != tap_get_end_state())
-	{
-		jlink_state_move();
-	}
-}
-
-static void jlink_reset(int trst, int srst)
-{
-	LOG_DEBUG("trst: %i, srst: %i", trst, srst);
-
-	/* Signals are active low */
-	if (srst == 0)
-	{
-		jlink_simple_command(EMU_CMD_HW_RESET1);
-	}
-	if (srst == 1)
-	{
-		jlink_simple_command(EMU_CMD_HW_RESET0);
-	}
-
-	if (trst == 1)
-	{
-		jlink_simple_command(EMU_CMD_HW_TRST0);
-	}
-
-	if (trst == 0)
-	{
-		jlink_simple_command(EMU_CMD_HW_TRST1);
-	}
-}
-
-static void jlink_simple_command(uint8_t command)
-{
-	int result;
-
-	DEBUG_JTAG_IO("0x%02x", command);
-
-	usb_out_buffer[0] = command;
-	result = jlink_usb_write(jlink_handle, 1);
-
-	if (result != 1)
-	{
-		LOG_ERROR("J-Link command 0x%02x failed (%d)", command, result);
-	}
-}
-
-static int jlink_get_status(void)
-{
-	int result;
-
-	jlink_simple_command(EMU_CMD_GET_STATE);
-
-	result = jlink_usb_read(jlink_handle, 8);
-	if (result != 8)
-	{
-		LOG_ERROR("J-Link command EMU_CMD_GET_STATE failed (%d)\n", result);
-		return ERROR_JTAG_DEVICE_ERROR;
-	}
-
-	int vref = usb_in_buffer[0] + (usb_in_buffer[1] << 8);
-	LOG_INFO("Vref = %d.%d TCK = %d TDI = %d TDO = %d TMS = %d SRST = %d TRST = %d\n", \
-		vref / 1000, vref % 1000, \
-		usb_in_buffer[2], usb_in_buffer[3], usb_in_buffer[4], \
-		usb_in_buffer[5], usb_in_buffer[6], usb_in_buffer[7]);
-
-	if (vref < 1500)
-		LOG_ERROR("Vref too low. Check Target Power\n");
-
-	return ERROR_OK;
-}
-
-static int jlink_get_version_info(void)
-{
-	int result;
-	int len;
-	uint32_t jlink_caps, jlink_max_size;
-
-	/* query hardware version */
-	jlink_simple_command(EMU_CMD_VERSION);
-
-	result = jlink_usb_read(jlink_handle, 2);
-	if (2 != result)
-	{
-		LOG_ERROR("J-Link command EMU_CMD_VERSION failed (%d)\n", result);
-		return ERROR_JTAG_DEVICE_ERROR;
-	}
-
-	len = buf_get_u32(usb_in_buffer, 0, 16);
-	if (len > JLINK_IN_BUFFER_SIZE)
-	{
-		LOG_ERROR("J-Link command EMU_CMD_VERSION impossible return length 0x%0x", len);
-		len = JLINK_IN_BUFFER_SIZE;
-	}
-
-	result = jlink_usb_read(jlink_handle, len);
-	if (result != len)
-	{
-		LOG_ERROR("J-Link command EMU_CMD_VERSION failed (%d)\n", result);
-		return ERROR_JTAG_DEVICE_ERROR;
-	}
-
-	usb_in_buffer[result] = 0;
-	LOG_INFO("%s", (char *)usb_in_buffer);
-
-	/* query hardware capabilities */
-	jlink_simple_command(EMU_CMD_GET_CAPS);
-
-	result = jlink_usb_read(jlink_handle, 4);
-	if (4 != result)
-	{
-		LOG_ERROR("J-Link command EMU_CMD_GET_CAPS failed (%d)\n", result);
-		return ERROR_JTAG_DEVICE_ERROR;
-	}
-
-	jlink_caps = buf_get_u32(usb_in_buffer, 0, 32);
-	LOG_INFO("JLink caps 0x%x", (unsigned)jlink_caps);
-
-	if (jlink_caps & (1 << EMU_CAP_GET_HW_VERSION))
-	{
-		/* query hardware version */
-		jlink_simple_command(EMU_CMD_GET_HW_VERSION);
-
-		result = jlink_usb_read(jlink_handle, 4);
-		if (4 != result)
-		{
-			LOG_ERROR("J-Link command EMU_CMD_GET_HW_VERSION failed (%d)\n", result);
-			return ERROR_JTAG_DEVICE_ERROR;
-		}
-
-		uint32_t jlink_hw_version = buf_get_u32(usb_in_buffer, 0, 32);
-		uint32_t major_revision = (jlink_hw_version / 10000) % 100;
-		if (major_revision >= 5)
-			jlink_hw_jtag_version = 3;
-
-		LOG_INFO("JLink hw version %i", (int)jlink_hw_version);
-	}
-
-	if (jlink_caps & (1 << EMU_CAP_GET_MAX_BLOCK_SIZE))
-	{
-		/* query hardware maximum memory block */
-		jlink_simple_command(EMU_CMD_GET_MAX_MEM_BLOCK);
-
-		result = jlink_usb_read(jlink_handle, 4);
-		if (4 != result)
-		{
-			LOG_ERROR("J-Link command EMU_CMD_GET_MAX_MEM_BLOCK failed (%d)\n", result);
-			return ERROR_JTAG_DEVICE_ERROR;
-		}
-
-		jlink_max_size = buf_get_u32(usb_in_buffer, 0, 32);
-		LOG_INFO("JLink max mem block %i", (int)jlink_max_size);
-	}
-
-	return ERROR_OK;
-}
-
-COMMAND_HANDLER(jlink_handle_jlink_info_command)
-{
-	if (jlink_get_version_info() == ERROR_OK)
-	{
-		/* attempt to get status */
-		jlink_get_status();
-	}
-
-	return ERROR_OK;
-}
-
-COMMAND_HANDLER(jlink_handle_jlink_hw_jtag_command)
-{
-	switch (CMD_ARGC) {
-	case 0:
-		command_print(CMD_CTX, "jlink hw jtag  %i", jlink_hw_jtag_version);
-		break;
-	case 1: {
-		int request_version = atoi(CMD_ARGV[0]);
-		switch (request_version) {
-		case 2: case 3:
-			jlink_hw_jtag_version = request_version;
-			break;
-		default:
-			return ERROR_COMMAND_SYNTAX_ERROR;
-		}
-		break;
-	}
-	default:
-		return ERROR_COMMAND_SYNTAX_ERROR;
-	}
-
-	return ERROR_OK;
-}
-
-static const struct command_registration jlink_command_handlers[] = {
-	{
-		.name = "jlink_info",
-		.handler = &jlink_handle_jlink_info_command,
-		.mode = COMMAND_EXEC,
-		.help = "show jlink info",
-	},
-	{
-		.name = "jlink_hw_jtag",
-		.handler = &jlink_handle_jlink_hw_jtag_command,
-		.mode = COMMAND_EXEC,
-		.help = "access J-Link HW JTAG command version",
-		.usage = "[2|3]",
-	},
-	COMMAND_REGISTRATION_DONE
-};
-
-struct jtag_interface jlink_interface = {
-		.name = "jlink",
-
-		.commands = jlink_command_handlers,
-
-		.execute_queue = &jlink_execute_queue,
-		.speed = &jlink_speed,
-		.speed_div = &jlink_speed_div,
-		.khz = &jlink_khz,
-
-		.init = &jlink_init,
-		.quit = &jlink_quit,
-	};
-
-/***************************************************************************/
-/* J-Link tap functions */
-
-
-static unsigned tap_length = 0;
-static uint8_t tms_buffer[JLINK_TAP_BUFFER_SIZE];
-static uint8_t tdi_buffer[JLINK_TAP_BUFFER_SIZE];
-static uint8_t tdo_buffer[JLINK_TAP_BUFFER_SIZE];
-
-struct pending_scan_result {
-	int first;	/* First bit position in tdo_buffer to read */
-	int length; /* Number of bits to read */
-	struct scan_command *command; /* Corresponding scan command */
-	uint8_t *buffer;
-};
-
-#define MAX_PENDING_SCAN_RESULTS 256
-
-static int pending_scan_results_length;
-static struct pending_scan_result pending_scan_results_buffer[MAX_PENDING_SCAN_RESULTS];
-
-static void jlink_tap_init(void)
-{
-	tap_length = 0;
-	pending_scan_results_length = 0;
-}
-
-static void jlink_tap_ensure_space(int scans, int bits)
-{
-	int available_scans = MAX_PENDING_SCAN_RESULTS - pending_scan_results_length;
-	int available_bits = JLINK_TAP_BUFFER_SIZE * 8 - tap_length - 32;
-
-	if (scans > available_scans || bits > available_bits)
-	{
-		jlink_tap_execute();
-	}
-}
-
-static void jlink_tap_append_step(int tms, int tdi)
-{
-	int index = tap_length / 8;
-
-	if (index >= JLINK_TAP_BUFFER_SIZE)
-	{
-		LOG_ERROR("jlink_tap_append_step: overflow");
-		*(uint32_t *)0xFFFFFFFF = 0;
-		exit(-1);
-	}
-
-	int bit_index = tap_length % 8;
-	uint8_t bit = 1 << bit_index;
-
-	// we do not pad TMS, so be sure to initialize all bits
-	if (0 == bit_index)
-	{
-		tms_buffer[index] = tdi_buffer[index] = 0;
-	}
-
-	if (tms)
-		tms_buffer[index] |= bit;
-	else
-		tms_buffer[index] &= ~bit;
-
-	if (tdi)
-		tdi_buffer[index] |= bit;
-	else
-		tdi_buffer[index] &= ~bit;
-
-	tap_length++;
-}
-
-static void jlink_tap_append_scan(int length, uint8_t *buffer, struct scan_command *command)
-{
-	struct pending_scan_result *pending_scan_result =
-		&pending_scan_results_buffer[pending_scan_results_length];
-	int i;
-
-	pending_scan_result->first = tap_length;
-	pending_scan_result->length = length;
-	pending_scan_result->command = command;
-	pending_scan_result->buffer = buffer;
-
-	for (i = 0; i < length; i++)
-	{
-		int tms = (i < (length - 1)) ? 0 : 1;
-		int tdi = (buffer[i / 8] & (1 << (i % 8))) != 0;
-		jlink_tap_append_step(tms, tdi);
-	}
-	pending_scan_results_length++;
-}
-
-/* Pad and send a tap sequence to the device, and receive the answer.
- * For the purpose of padding we assume that we are in idle or pause state. */
-static int jlink_tap_execute(void)
-{
-	int byte_length;
-	int i;
-	int result;
-
-	if (!tap_length)
-		return ERROR_OK;
-
-	/* JLink returns an extra NULL in packet when size of incoming
-	 * message is a multiple of 64, creates problems with USB comms.
-	 * WARNING: This will interfere with tap state counting. */
-	while ((DIV_ROUND_UP(tap_length, 8) % 64) == 0)
-	{
-		jlink_tap_append_step((tap_get_state() == TAP_RESET)?1:0, 0);
-	}
-
-	// number of full bytes (plus one if some would be left over)
-	byte_length = DIV_ROUND_UP(tap_length, 8);
-
-	bool use_jtag3 = jlink_hw_jtag_version >= 3;
-	usb_out_buffer[0] = use_jtag3 ? EMU_CMD_HW_JTAG3 : EMU_CMD_HW_JTAG2;
-	usb_out_buffer[1] = 0;
-	usb_out_buffer[2] = (tap_length >> 0) & 0xff;
-	usb_out_buffer[3] = (tap_length >> 8) & 0xff;
-	memcpy(usb_out_buffer + 4, tms_buffer, byte_length);
-	memcpy(usb_out_buffer + 4 + byte_length, tdi_buffer, byte_length);
-
-	jlink_last_state = jtag_debug_state_machine(tms_buffer, tdi_buffer,
-			tap_length, jlink_last_state);
-
-	result = jlink_usb_message(jlink_handle, 4 + 2 * byte_length, byte_length);
-	if (result != byte_length)
-	{
-		LOG_ERROR("jlink_tap_execute, wrong result %d (expected %d)", result, byte_length);
-		jlink_tap_init();
-		return ERROR_JTAG_QUEUE_FAILED;
-	}
-
-	memcpy(tdo_buffer, usb_in_buffer, byte_length);
-
-	for (i = 0; i < pending_scan_results_length; i++)
-	{
-		struct pending_scan_result *pending_scan_result = &pending_scan_results_buffer[i];
-		uint8_t *buffer = pending_scan_result->buffer;
-		int length = pending_scan_result->length;
-		int first = pending_scan_result->first;
-		struct scan_command *command = pending_scan_result->command;
-
-		/* Copy to buffer */
-		buf_set_buf(tdo_buffer, first, buffer, 0, length);
-
-		DEBUG_JTAG_IO("pending scan result, length = %d", length);
-
-#ifdef _DEBUG_USB_COMMS_
-		jlink_debug_buffer(buffer, DIV_ROUND_UP(length, 8));
-#endif
-
-		if (jtag_read_buffer(buffer, command) != ERROR_OK)
-		{
-			jlink_tap_init();
-			return ERROR_JTAG_QUEUE_FAILED;
-		}
-
-		if (pending_scan_result->buffer != NULL)
-		{
-			free(pending_scan_result->buffer);
-		}
-	}
-
-	jlink_tap_init();
-	return ERROR_OK;
-}
-
-/*****************************************************************************/
-/* JLink USB low-level functions */
-
-static struct jlink* jlink_usb_open()
-{
-	usb_init();
-
-	const uint16_t vids[] = { VID, 0 };
-	const uint16_t pids[] = { PID, 0 };
-	struct usb_dev_handle *dev;
-	if (jtag_usb_open(vids, pids, &dev) != ERROR_OK)
-		return NULL;
-
-	/* BE ***VERY CAREFUL*** ABOUT MAKING CHANGES IN THIS
-	 * AREA!!!!!!!!!!!  The behavior of libusb is not completely
-	 * consistent across Windows, Linux, and Mac OS X platforms.
-	 * The actions taken in the following compiler conditionals may
-	 * not agree with published documentation for libusb, but were
-	 * found to be necessary through trials and tribulations.  Even
-	 * little tweaks can break one or more platforms, so if you do
-	 * make changes test them carefully on all platforms before
-	 * committing them!
-	 */
-
-#if IS_WIN32 == 0
-
-	usb_reset(dev);
-
-#if IS_DARWIN == 0
-
-	int timeout = 5;
-	/* reopen jlink after usb_reset
-	 * on win32 this may take a second or two to re-enumerate */
-	int retval;
-	while ((retval = jtag_usb_open(vids, pids, &dev)) != ERROR_OK)
-	{
-		usleep(1000);
-		timeout--;
-		if (!timeout) {
-			break;
-		}
-	}
-	if (ERROR_OK != retval)
-		return NULL;
-#endif
-
-#endif
-
-	/* usb_set_configuration required under win32 */
-	struct usb_device *udev = usb_device(dev);
-	usb_set_configuration(dev, udev->config[0].bConfigurationValue);
-	usb_claim_interface(dev, 0);
-
-#if 0
-	/*
-	 * This makes problems under Mac OS X. And is not needed
-	 * under Windows. Hopefully this will not break a linux build
-	 */
-	usb_set_altinterface(result->usb_handle, 0);
-#endif
-	struct usb_interface *iface = udev->config->interface;
-	struct usb_interface_descriptor *desc = iface->altsetting;
-	for (int i = 0; i < desc->bNumEndpoints; i++)
-	{
-		uint8_t epnum = desc->endpoint[i].bEndpointAddress;
-		bool is_input = epnum & 0x80;
-		LOG_DEBUG("usb ep %s %02x", is_input ? "in" : "out", epnum);
-		if (is_input)
-			jlink_read_ep = epnum;
-		else
-			jlink_write_ep = epnum;
-	}
-
-	struct jlink *result = malloc(sizeof(struct jlink));
-	result->usb_handle = dev;
-	return result;
-}
-
-static void jlink_usb_close(struct jlink *jlink)
-{
-	usb_close(jlink->usb_handle);
-	free(jlink);
-}
-
-/* Send a message and receive the reply. */
-static int jlink_usb_message(struct jlink *jlink, int out_length, int in_length)
-{
-	int result;
-
-	result = jlink_usb_write(jlink, out_length);
-	if (result != out_length)
-	{
-		LOG_ERROR("usb_bulk_write failed (requested=%d, result=%d)",
-				out_length, result);
-		return ERROR_JTAG_DEVICE_ERROR;
-	}
-
-	result = jlink_usb_read(jlink, in_length);
-	if ((result != in_length) && (result != (in_length + 1)))
-	{
-		LOG_ERROR("usb_bulk_read failed (requested=%d, result=%d)",
-				in_length, result);
-		return ERROR_JTAG_DEVICE_ERROR;
-	}
-
-	if (jlink_hw_jtag_version < 3)
-		return result;
-
-	int result2 = ERROR_OK;
-	if (result == in_length)
-	{
-		/* Must read the result from the EMU too */
-		result2 = jlink_usb_read_emu_result(jlink);
-		if (1 != result2)
-		{
-			LOG_ERROR("jlink_usb_read_emu_result retried requested = 1, result=%d, in_length=%i", result2,in_length);
-			/* Try again once, should only happen if (in_length%64 == 0) */
-			result2 = jlink_usb_read_emu_result(jlink);
-			if (1 != result2)
-			{
-				LOG_ERROR("jlink_usb_read_emu_result failed "
-					"(requested = 1, result=%d)", result2);
-				return ERROR_JTAG_DEVICE_ERROR;
-			}
-		}
-
-		/* Check the result itself */
-		result2 = usb_emu_result_buffer[0];
-	}
-	else
-	{
-		/* Save the result, then remove it from return value */
-		result2 = usb_in_buffer[result--];
-	}
-
-	if (result2)
-	{
-		LOG_ERROR("jlink_usb_message failed with result=%d)", result2);
-		return ERROR_JTAG_DEVICE_ERROR;
-	}
-
-	return result;
-}
-
-/* calls the given usb_bulk_* function, allowing for the data to trickle in with some timeouts  */
-static int usb_bulk_with_retries(
-		int (*f)(usb_dev_handle *, int, char *, int, int),
-		usb_dev_handle *dev, int ep,
-		char *bytes, int size, int timeout)
-{
-	int tries = 3, count = 0;
-
-	while (tries && (count < size))
-	{
-		int result = f(dev, ep, bytes + count, size - count, timeout);
-		if (result > 0)
-			count += result;
-		else if ((-ETIMEDOUT != result) || !--tries)
-			return result;
-	}
-	return count;
-}
-
-static int wrap_usb_bulk_write(usb_dev_handle *dev, int ep,
-			       char *buff, int size, int timeout)
-{
-	/* usb_bulk_write() takes const char *buff */
-	return usb_bulk_write(dev, ep, buff, size, timeout);
-}
-
-static inline int usb_bulk_write_ex(usb_dev_handle *dev, int ep,
-		char *bytes, int size, int timeout)
-{
-	return usb_bulk_with_retries(&wrap_usb_bulk_write,
-			dev, ep, bytes, size, timeout);
-}
-
-static inline int usb_bulk_read_ex(usb_dev_handle *dev, int ep,
-		char *bytes, int size, int timeout)
-{
-	return usb_bulk_with_retries(&usb_bulk_read,
-			dev, ep, bytes, size, timeout);
-}
-
-/* Write data from out_buffer to USB. */
-static int jlink_usb_write(struct jlink *jlink, int out_length)
-{
-	int result;
-
-	if (out_length > JLINK_OUT_BUFFER_SIZE)
-	{
-		LOG_ERROR("jlink_write illegal out_length=%d (max=%d)", out_length, JLINK_OUT_BUFFER_SIZE);
-		return -1;
-	}
-
-	result = usb_bulk_write_ex(jlink->usb_handle, jlink_write_ep,
-		(char *)usb_out_buffer, out_length, JLINK_USB_TIMEOUT);
-
-	DEBUG_JTAG_IO("jlink_usb_write, out_length = %d, result = %d", out_length, result);
-
-#ifdef _DEBUG_USB_COMMS_
-	jlink_debug_buffer(usb_out_buffer, out_length);
-#endif
-	return result;
-}
-
-/* Read data from USB into in_buffer. */
-static int jlink_usb_read(struct jlink *jlink, int expected_size)
-{
-	int result = usb_bulk_read_ex(jlink->usb_handle, jlink_read_ep,
-		(char *)usb_in_buffer, expected_size, JLINK_USB_TIMEOUT);
-
-	DEBUG_JTAG_IO("jlink_usb_read, result = %d", result);
-
-#ifdef _DEBUG_USB_COMMS_
-	jlink_debug_buffer(usb_in_buffer, result);
-#endif
-	return result;
-}
-
-/* Read the result from the previous EMU cmd into result_buffer. */
-static int jlink_usb_read_emu_result(struct jlink *jlink)
-{
-	int result = usb_bulk_read_ex(jlink->usb_handle, jlink_read_ep,
-		(char *)usb_emu_result_buffer, 1 /* JLINK_EMU_RESULT_BUFFER_SIZE */,
-		JLINK_USB_TIMEOUT);
-
-	DEBUG_JTAG_IO("jlink_usb_read_result, result = %d", result);
-
-#ifdef _DEBUG_USB_COMMS_
-	jlink_debug_buffer(usb_emu_result_buffer, result);
-#endif
-	return result;
-}
-
-#ifdef _DEBUG_USB_COMMS_
-#define BYTES_PER_LINE  16
-
-static void jlink_debug_buffer(uint8_t *buffer, int length)
-{
-	char line[81];
-	char s[4];
-	int i;
-	int j;
-
-	for (i = 0; i < length; i += BYTES_PER_LINE)
-	{
-		snprintf(line, 5, "%04x", i);
-		for (j = i; j < i + BYTES_PER_LINE && j < length; j++)
-		{
-			snprintf(s, 4, " %02x", buffer[j]);
-			strcat(line, s);
-		}
-		LOG_DEBUG("%s", line);
-	}
-}
-#endif
-