X-Git-Url: https://review.openocd.org/gitweb?p=openocd.git;a=blobdiff_plain;f=src%2Fjtag%2Fdrivers%2Fjlink.c;h=c81579ab29e9a39242f584f53c020b57aed6ecda;hp=807bdba965350d80707f4613a9ea7dfd162dba3b;hb=57962f4d1c2db12dffa03c7357f5d7e0d8f71fb8;hpb=4b608d7fea61855b9a284c5a8e0a2fc167bd7d1f

diff --git a/src/jtag/drivers/jlink.c b/src/jtag/drivers/jlink.c
index 807bdba965..c81579ab29 100644
--- a/src/jtag/drivers/jlink.c
+++ b/src/jtag/drivers/jlink.c
@@ -11,6 +11,9 @@
  *   Copyright (C) 2015 by Marc Schink                                     *
  *   openocd-dev@marcschink.de                                             *
  *                                                                         *
+ *   Copyright (C) 2015 by Paul Fertser                                    *
+ *   fercerpav@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     *
@@ -22,8 +25,7 @@
  *   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.,                                       *
+ *   along with this program.  If not, see <http://www.gnu.org/licenses/>. *
  ***************************************************************************/
 
 #ifdef HAVE_CONFIG_H
@@ -48,9 +50,9 @@ static uint8_t caps[JAYLINK_DEV_EXT_CAPS_SIZE];
 
 static uint32_t serial_number;
 static bool use_serial_number;
-static uint8_t usb_address;
+static enum jaylink_usb_address usb_address;
 static bool use_usb_address;
-static uint8_t iface = JAYLINK_TIF_JTAG;
+static enum jaylink_target_interface iface = JAYLINK_TIF_JTAG;
 static bool trace_enabled;
 
 #define JLINK_MAX_SPEED			12000
@@ -83,23 +85,34 @@ static struct device_config tmp_config;
 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_stableclocks(int num_cycles);
 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 int jlink_swd_run_queue(struct adiv5_dap *dap);
-static void jlink_swd_queue_cmd(struct adiv5_dap *dap, uint8_t cmd,
-		uint32_t *dst, uint32_t data);
-static int jlink_swd_switch_seq(struct adiv5_dap *dap,
-		enum swd_special_seq seq);
+static int jlink_swd_run_queue(void);
+static void jlink_swd_queue_cmd(uint8_t cmd, uint32_t *dst, uint32_t data, uint32_t ap_delay_clk);
+static int jlink_swd_switch_seq(enum swd_special_seq seq);
 
 /* 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);
+static int jlink_flush(void);
+/**
+ * Queue data to go out and in, flushing the queue as many times as
+ * necessary.
+ *
+ * @param out A pointer to TDI data, if NULL, old stale data will be used.
+ * @param out_offset A bit offset for TDI data.
+ * @param tms_out A pointer to TMS data, if NULL, zeroes will be emitted.
+ * @param tms_offset A bit offset for TMS data.
+ * @param in A pointer to store TDO data to, if NULL the data will be discarded.
+ * @param in_offset A bit offset for TDO data.
+ * @param length Amount of bits to transfer out and in.
+ *
+ * @retval This function doesn't return any value.
+ */
+static void jlink_clock_data(const uint8_t *out, unsigned out_offset,
+			     const uint8_t *tms_out, unsigned tms_offset,
+			     uint8_t *in, unsigned in_offset,
+			     unsigned length);
 
 static enum tap_state jlink_last_state = TAP_RESET;
 static int queued_retval;
@@ -107,6 +120,12 @@ static int queued_retval;
 /***************************************************************************/
 /* External interface implementation */
 
+static void jlink_execute_stableclocks(struct jtag_command *cmd)
+{
+	DEBUG_JTAG_IO("stableclocks %i cycles", cmd->cmd.runtest->num_cycles);
+	jlink_stableclocks(cmd->cmd.runtest->num_cycles);
+}
+
 static void jlink_execute_runtest(struct jtag_command *cmd)
 {
 	DEBUG_JTAG_IO("runtest %i cycles, end in %i", cmd->cmd.runtest->num_cycles,
@@ -135,19 +154,95 @@ static void jlink_execute_pathmove(struct jtag_command *cmd)
 
 static void jlink_execute_scan(struct jtag_command *cmd)
 {
-	int scan_size;
-	enum scan_type type;
-	uint8_t *buffer;
+	DEBUG_JTAG_IO("%s type:%d", cmd->cmd.scan->ir_scan ? "IRSCAN" : "DRSCAN",
+		jtag_scan_type(cmd->cmd.scan));
+
+	/* Make sure there are no trailing fields with num_bits == 0, or the logic below will fail. */
+	while (cmd->cmd.scan->num_fields > 0
+			&& cmd->cmd.scan->fields[cmd->cmd.scan->num_fields - 1].num_bits == 0) {
+		cmd->cmd.scan->num_fields--;
+		LOG_DEBUG("discarding trailing empty field");
+	}
 
-	DEBUG_JTAG_IO("scan end in %s", tap_state_name(cmd->cmd.scan->end_state));
+	if (cmd->cmd.scan->num_fields == 0) {
+		LOG_DEBUG("empty scan, doing nothing");
+		return;
+	}
+
+	if (cmd->cmd.scan->ir_scan) {
+		if (tap_get_state() != TAP_IRSHIFT) {
+			jlink_end_state(TAP_IRSHIFT);
+			jlink_state_move();
+		}
+	} else {
+		if (tap_get_state() != TAP_DRSHIFT) {
+			jlink_end_state(TAP_DRSHIFT);
+			jlink_state_move();
+		}
+	}
 
 	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);
+	struct scan_field *field = cmd->cmd.scan->fields;
+	unsigned scan_size = 0;
+
+	for (int i = 0; i < cmd->cmd.scan->num_fields; i++, field++) {
+		scan_size += field->num_bits;
+		DEBUG_JTAG_IO("%s%s field %d/%d %d bits",
+			field->in_value ? "in" : "",
+			field->out_value ? "out" : "",
+			i,
+			cmd->cmd.scan->num_fields,
+			field->num_bits);
+
+		if (i == cmd->cmd.scan->num_fields - 1 && tap_get_state() != tap_get_end_state()) {
+			/* Last field, and we're leaving IRSHIFT/DRSHIFT. Clock last bit during tap
+			 * movement. This last field can't have length zero, it was checked above. */
+			jlink_clock_data(field->out_value,
+					 0,
+					 NULL,
+					 0,
+					 field->in_value,
+					 0,
+					 field->num_bits - 1);
+			uint8_t last_bit = 0;
+			if (field->out_value)
+				bit_copy(&last_bit, 0, field->out_value, field->num_bits - 1, 1);
+			uint8_t tms_bits = 0x01;
+			jlink_clock_data(&last_bit,
+					 0,
+					 &tms_bits,
+					 0,
+					 field->in_value,
+					 field->num_bits - 1,
+					 1);
+			tap_set_state(tap_state_transition(tap_get_state(), 1));
+			jlink_clock_data(NULL,
+					 0,
+					 &tms_bits,
+					 1,
+					 NULL,
+					 0,
+					 1);
+			tap_set_state(tap_state_transition(tap_get_state(), 0));
+		} else
+			jlink_clock_data(field->out_value,
+					 0,
+					 NULL,
+					 0,
+					 field->in_value,
+					 0,
+					 field->num_bits);
+	}
+
+	if (tap_get_state() != tap_get_end_state()) {
+		jlink_end_state(tap_get_end_state());
+		jlink_state_move();
+	}
 
-	type = jtag_scan_type(cmd->cmd.scan);
-	jlink_scan(cmd->cmd.scan->ir_scan, type, buffer, scan_size, cmd->cmd.scan);
+	DEBUG_JTAG_IO("%s scan, %i bits, end in %s",
+		(cmd->cmd.scan->ir_scan) ? "IR" : "DR", scan_size,
+		tap_state_name(tap_get_end_state()));
 }
 
 static void jlink_execute_reset(struct jtag_command *cmd)
@@ -155,21 +250,24 @@ 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_flush();
 	jlink_reset(cmd->cmd.reset->trst, cmd->cmd.reset->srst);
-	jlink_tap_execute();
+	jlink_flush();
 }
 
 static void jlink_execute_sleep(struct jtag_command *cmd)
 {
 	DEBUG_JTAG_IO("sleep %" PRIi32 "", cmd->cmd.sleep->us);
-	jlink_tap_execute();
+	jlink_flush();
 	jtag_sleep(cmd->cmd.sleep->us);
 }
 
 static int jlink_execute_command(struct jtag_command *cmd)
 {
 	switch (cmd->type) {
+		case JTAG_STABLECLOCKS:
+			jlink_execute_stableclocks(cmd);
+			break;
 		case JTAG_RUNTEST:
 			jlink_execute_runtest(cmd);
 			break;
@@ -210,27 +308,26 @@ static int jlink_execute_queue(void)
 		cmd = cmd->next;
 	}
 
-	return jlink_tap_execute();
+	return jlink_flush();
 }
 
 static int jlink_speed(int speed)
 {
 	int ret;
-	uint32_t freq;
-	uint16_t div;
+	struct jaylink_speed tmp;
 	int max_speed;
 
 	if (jaylink_has_cap(caps, JAYLINK_DEV_CAP_GET_SPEEDS)) {
-		ret = jaylink_get_speeds(devh, &freq, &div);
+		ret = jaylink_get_speeds(devh, &tmp);
 
 		if (ret != JAYLINK_OK) {
 			LOG_ERROR("jaylink_get_speeds() failed: %s.",
-				jaylink_strerror_name(ret));
+				jaylink_strerror(ret));
 			return ERROR_JTAG_DEVICE_ERROR;
 		}
 
-		freq = freq / 1000;
-		max_speed = freq / div;
+		tmp.freq /= 1000;
+		max_speed = tmp.freq / tmp.div;
 	} else {
 		max_speed = JLINK_MAX_SPEED;
 	}
@@ -252,7 +349,7 @@ static int jlink_speed(int speed)
 
 	if (ret != JAYLINK_OK) {
 		LOG_ERROR("jaylink_set_speed() failed: %s.",
-			jaylink_strerror_name(ret));
+			jaylink_strerror(ret));
 		return ERROR_JTAG_DEVICE_ERROR;
 	}
 
@@ -281,7 +378,7 @@ static bool read_device_config(struct device_config *cfg)
 
 	if (ret != JAYLINK_OK) {
 		LOG_ERROR("jaylink_read_raw_config() failed: %s.",
-			jaylink_strerror_name(ret));
+			jaylink_strerror(ret));
 		return false;
 	}
 
@@ -312,7 +409,7 @@ static int select_interface(void)
 
 	if (ret != JAYLINK_OK) {
 		LOG_ERROR("jaylink_get_available_interfaces() failed: %s.",
-			jaylink_strerror_name(ret));
+			jaylink_strerror(ret));
 		return ERROR_JTAG_INIT_FAILED;
 	}
 
@@ -321,11 +418,11 @@ static int select_interface(void)
 		return ERROR_JTAG_INIT_FAILED;
 	}
 
-	ret = jaylink_select_interface(devh, iface);
+	ret = jaylink_select_interface(devh, iface, NULL);
 
 	if (ret < 0) {
 		LOG_ERROR("jaylink_select_interface() failed: %s.",
-			jaylink_strerror_name(ret));
+			jaylink_strerror(ret));
 		return ERROR_JTAG_INIT_FAILED;
 	}
 
@@ -335,23 +432,23 @@ static int select_interface(void)
 static int jlink_register(void)
 {
 	int ret;
-	int i;
+	size_t i;
 	bool handle_found;
+	size_t count;
 
 	if (!jaylink_has_cap(caps, JAYLINK_DEV_CAP_REGISTER))
 		return ERROR_OK;
 
-	ret = jaylink_register(devh, &conn, connlist, NULL, NULL);
+	ret = jaylink_register(devh, &conn, connlist, &count);
 
-	if (ret < 0) {
-		LOG_ERROR("jaylink_register() failed: %s.",
-			jaylink_strerror_name(ret));
+	if (ret != JAYLINK_OK) {
+		LOG_ERROR("jaylink_register() failed: %s.", jaylink_strerror(ret));
 		return ERROR_FAIL;
 	}
 
 	handle_found = false;
 
-	for (i = 0; i < ret; i++) {
+	for (i = 0; i < count; i++) {
 		if (connlist[i].handle == conn.handle) {
 			handle_found = true;
 			break;
@@ -384,7 +481,7 @@ static bool adjust_swd_buffer_size(void)
 
 	if (ret != JAYLINK_OK) {
 		LOG_ERROR("jaylink_get_free_memory() failed: %s.",
-			jaylink_strerror_name(ret));
+			jaylink_strerror(ret));
 		return false;
 	}
 
@@ -404,6 +501,39 @@ static bool adjust_swd_buffer_size(void)
 	return true;
 }
 
+static int jaylink_log_handler(const struct jaylink_context *ctx,
+		enum jaylink_log_level level, const char *format, va_list args,
+		void *user_data)
+{
+	enum log_levels tmp;
+
+	switch (level) {
+	case JAYLINK_LOG_LEVEL_ERROR:
+		tmp = LOG_LVL_ERROR;
+		break;
+	case JAYLINK_LOG_LEVEL_WARNING:
+		tmp = LOG_LVL_WARNING;
+		break;
+	/*
+	 * Forward info messages to the debug output because they are more verbose
+	 * than info messages of OpenOCD.
+	 */
+	case JAYLINK_LOG_LEVEL_INFO:
+	case JAYLINK_LOG_LEVEL_DEBUG:
+		tmp = LOG_LVL_DEBUG;
+		break;
+	case JAYLINK_LOG_LEVEL_DEBUG_IO:
+		tmp = LOG_LVL_DEBUG_IO;
+		break;
+	default:
+		tmp = LOG_LVL_WARNING;
+	}
+
+	log_vprintf_lf(tmp, __FILE__, __LINE__, __func__, format, args);
+
+	return 0;
+}
+
 static int jlink_init(void)
 {
 	int ret;
@@ -414,51 +544,108 @@ static int jlink_init(void)
 	char *firmware_version;
 	struct jaylink_hardware_version hwver;
 	struct jaylink_hardware_status hwstatus;
+	enum jaylink_usb_address address;
+	size_t length;
+	size_t num_devices;
+	uint32_t host_interfaces;
+
+	LOG_DEBUG("Using libjaylink %s (compiled with %s).",
+		jaylink_version_package_get_string(), JAYLINK_VERSION_PACKAGE_STRING);
+
+	if (!jaylink_library_has_cap(JAYLINK_CAP_HIF_USB) && use_usb_address) {
+		LOG_ERROR("J-Link driver does not support USB devices.");
+		return ERROR_JTAG_INIT_FAILED;
+	}
 
 	ret = jaylink_init(&jayctx);
 
 	if (ret != JAYLINK_OK) {
-		LOG_ERROR("jaylink_init() failed: %s.",
-			jaylink_strerror_name(ret));
+		LOG_ERROR("jaylink_init() failed: %s.", jaylink_strerror(ret));
 		return ERROR_JTAG_INIT_FAILED;
 	}
 
-	ret = jaylink_get_device_list(jayctx, &devs);
+	ret = jaylink_log_set_callback(jayctx, &jaylink_log_handler, NULL);
 
-	if (ret < 0) {
-		LOG_ERROR("jaylink_get_device_list() failed: %s.",
-			jaylink_strerror_name(ret));
+	if (ret != JAYLINK_OK) {
+		LOG_ERROR("jaylink_log_set_callback() failed: %s.",
+			jaylink_strerror(ret));
 		jaylink_exit(jayctx);
 		return ERROR_JTAG_INIT_FAILED;
 	}
 
-	found_device = false;
+	host_interfaces = JAYLINK_HIF_USB;
+
+	if (use_serial_number)
+		host_interfaces |= JAYLINK_HIF_TCP;
 
-	if (!use_serial_number && !use_usb_address)
-		LOG_INFO("No device selected, using first device.");
+	ret = jaylink_discovery_scan(jayctx, host_interfaces);
+
+	if (ret != JAYLINK_OK) {
+		LOG_ERROR("jaylink_discovery_scan() failed: %s.",
+			jaylink_strerror(ret));
+		jaylink_exit(jayctx);
+		return ERROR_JTAG_INIT_FAILED;
+	}
+
+	ret = jaylink_get_devices(jayctx, &devs, &num_devices);
+
+	if (ret != JAYLINK_OK) {
+		LOG_ERROR("jaylink_get_devices() failed: %s.", jaylink_strerror(ret));
+		jaylink_exit(jayctx);
+		return ERROR_JTAG_INIT_FAILED;
+	}
+
+	if (!use_serial_number && !use_usb_address && num_devices > 1) {
+		LOG_ERROR("Multiple devices found, specify the desired device.");
+		jaylink_free_devices(devs, true);
+		jaylink_exit(jayctx);
+		return ERROR_JTAG_INIT_FAILED;
+	}
+
+	found_device = false;
 
 	for (i = 0; devs[i]; i++) {
-		jaylink_device_get_serial_number(devs[i], &tmp);
-		ret = jaylink_device_get_usb_address(devs[i]);
+		if (use_serial_number) {
+			ret = jaylink_device_get_serial_number(devs[i], &tmp);
+
+			if (ret == JAYLINK_ERR_NOT_AVAILABLE) {
+				continue;
+			} else if (ret != JAYLINK_OK) {
+				LOG_WARNING("jaylink_device_get_serial_number() failed: %s.",
+					jaylink_strerror(ret));
+				continue;
+			}
+
+			if (serial_number != tmp)
+				continue;
+		}
 
-		if (use_usb_address && usb_address != ret)
-			continue;
+		if (use_usb_address) {
+			ret = jaylink_device_get_usb_address(devs[i], &address);
 
-		if (use_serial_number && tmp != serial_number)
-			continue;
+			if (ret == JAYLINK_ERR_NOT_SUPPORTED) {
+				continue;
+			} else if (ret != JAYLINK_OK) {
+				LOG_WARNING("jaylink_device_get_usb_address() failed: %s.",
+					jaylink_strerror(ret));
+				continue;
+			}
+
+			if (usb_address != address)
+				continue;
+		}
 
 		ret = jaylink_open(devs[i], &devh);
 
-		if (ret != JAYLINK_OK) {
-			LOG_ERROR("Failed to open device: %s.", jaylink_strerror_name(ret));
-			continue;
+		if (ret == JAYLINK_OK) {
+			found_device = true;
+			break;
 		}
 
-		found_device = true;
-		break;
+		LOG_ERROR("Failed to open device: %s.", jaylink_strerror(ret));
 	}
 
-	jaylink_free_device_list(devs, 1);
+	jaylink_free_devices(devs, true);
 
 	if (!found_device) {
 		LOG_ERROR("No J-Link device found.");
@@ -471,26 +658,26 @@ static int jlink_init(void)
 	 * some devices are known to be sensitive regarding the order.
 	 */
 
-	ret = jaylink_get_firmware_version(devh, &firmware_version);
+	ret = jaylink_get_firmware_version(devh, &firmware_version, &length);
 
-	if (ret > 0) {
-		LOG_INFO("%s", firmware_version);
-		free(firmware_version);
-	} else if (!ret) {
-		LOG_WARNING("Device responds empty firmware version string.");
-	} else {
+	if (ret != JAYLINK_OK) {
 		LOG_ERROR("jaylink_get_firmware_version() failed: %s.",
-			jaylink_strerror_name(ret));
+			jaylink_strerror(ret));
 		jaylink_close(devh);
 		jaylink_exit(jayctx);
 		return ERROR_JTAG_INIT_FAILED;
+	} else if (length > 0) {
+		LOG_INFO("%s", firmware_version);
+		free(firmware_version);
+	} else {
+		LOG_WARNING("Device responds empty firmware version string.");
 	}
 
 	memset(caps, 0, JAYLINK_DEV_EXT_CAPS_SIZE);
 	ret = jaylink_get_caps(devh, caps);
 
 	if (ret != JAYLINK_OK) {
-		LOG_ERROR("jaylink_get_caps() failed: %s.", jaylink_strerror_name(ret));
+		LOG_ERROR("jaylink_get_caps() failed: %s.", jaylink_strerror(ret));
 		jaylink_close(devh);
 		jaylink_exit(jayctx);
 		return ERROR_JTAG_INIT_FAILED;
@@ -501,21 +688,21 @@ static int jlink_init(void)
 
 		if (ret != JAYLINK_OK) {
 			LOG_ERROR("jaylink_get_extended_caps() failed:  %s.",
-				jaylink_strerror_name(ret));
+				jaylink_strerror(ret));
 			jaylink_close(devh);
 			jaylink_exit(jayctx);
 			return ERROR_JTAG_INIT_FAILED;
 		}
 	}
 
-	jtag_command_version = JAYLINK_JTAG_V2;
+	jtag_command_version = JAYLINK_JTAG_VERSION_2;
 
 	if (jaylink_has_cap(caps, JAYLINK_DEV_CAP_GET_HW_VERSION)) {
 		ret = jaylink_get_hardware_version(devh, &hwver);
 
 		if (ret != JAYLINK_OK) {
 			LOG_ERROR("Failed to retrieve hardware version: %s.",
-				jaylink_strerror_name(ret));
+				jaylink_strerror(ret));
 			jaylink_close(devh);
 			jaylink_exit(jayctx);
 			return ERROR_JTAG_INIT_FAILED;
@@ -524,7 +711,7 @@ static int jlink_init(void)
 		LOG_INFO("Hardware version: %u.%02u", hwver.major, hwver.minor);
 
 		if (hwver.major >= 5)
-			jtag_command_version = JAYLINK_JTAG_V3;
+			jtag_command_version = JAYLINK_JTAG_VERSION_3;
 	}
 
 	if (iface == JAYLINK_TIF_SWD) {
@@ -556,7 +743,7 @@ static int jlink_init(void)
 
 	if (ret != JAYLINK_OK) {
 		LOG_ERROR("jaylink_get_hardware_status() failed: %s.",
-			jaylink_strerror_name(ret));
+			jaylink_strerror(ret));
 		jaylink_close(devh);
 		jaylink_exit(jayctx);
 		return ERROR_JTAG_INIT_FAILED;
@@ -567,7 +754,7 @@ static int jlink_init(void)
 
 	conn.handle = 0;
 	conn.pid = 0;
-	conn.hid = 0;
+	strcpy(conn.hid, "0.0.0.0");
 	conn.iid = 0;
 	conn.cid = 0;
 
@@ -599,10 +786,10 @@ static int jlink_init(void)
 		 * 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);
+		uint8_t tms = 0xff;
+		jlink_clock_data(NULL, 0, &tms, 0, NULL, 0, 8);
 
-		jlink_tap_execute();
+		jlink_flush();
 	}
 
 	return ERROR_OK;
@@ -611,21 +798,21 @@ static int jlink_init(void)
 static int jlink_quit(void)
 {
 	int ret;
+	size_t count;
 
 	if (trace_enabled) {
 		ret = jaylink_swo_stop(devh);
 
 		if (ret != JAYLINK_OK)
-			LOG_ERROR("jaylink_swo_stop() failed: %s.",
-				jaylink_strerror_name(ret));
+			LOG_ERROR("jaylink_swo_stop() failed: %s.", jaylink_strerror(ret));
 	}
 
 	if (jaylink_has_cap(caps, JAYLINK_DEV_CAP_REGISTER)) {
-		ret = jaylink_unregister(devh, &conn, connlist, NULL, NULL);
+		ret = jaylink_unregister(devh, &conn, connlist, &count);
 
-		if (ret < 0)
+		if (ret != JAYLINK_OK)
 			LOG_ERROR("jaylink_unregister() failed: %s.",
-				jaylink_strerror_name(ret));
+				jaylink_strerror(ret));
 	}
 
 	jaylink_close(devh);
@@ -650,18 +837,13 @@ static void jlink_end_state(tap_state_t state)
 /* Goes to the end state. */
 static void jlink_state_move(void)
 {
-	int i;
-	int tms = 0;
 	uint8_t tms_scan;
 	uint8_t tms_scan_bits;
 
 	tms_scan = tap_get_tms_path(tap_get_state(), tap_get_end_state());
 	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);
-	}
+	jlink_clock_data(NULL, 0, &tms_scan, 0, NULL, 0, tms_scan_bits);
 
 	tap_set_state(tap_get_end_state());
 }
@@ -669,12 +851,13 @@ static void jlink_state_move(void)
 static void jlink_path_move(int num_states, tap_state_t *path)
 {
 	int i;
+	uint8_t tms = 0xff;
 
 	for (i = 0; i < num_states; i++) {
 		if (path[i] == tap_state_transition(tap_get_state(), false))
-			jlink_tap_append_step(0, 0);
+			jlink_clock_data(NULL, 0, NULL, 0, NULL, 0, 1);
 		else if (path[i] == tap_state_transition(tap_get_state(), true))
-			jlink_tap_append_step(1, 0);
+			jlink_clock_data(NULL, 0, &tms, 0, NULL, 0, 1);
 		else {
 			LOG_ERROR("BUG: %s -> %s isn't a valid TAP transition.",
 				tap_state_name(tap_get_state()), tap_state_name(path[i]));
@@ -687,13 +870,19 @@ static void jlink_path_move(int num_states, tap_state_t *path)
 	tap_set_end_state(tap_get_state());
 }
 
-static void jlink_runtest(int num_cycles)
+static void jlink_stableclocks(int num_cycles)
 {
 	int i;
 
-	tap_state_t saved_end_state = tap_get_end_state();
+	uint8_t tms = tap_get_state() == TAP_RESET;
+	/* Execute num_cycles. */
+	for (i = 0; i < num_cycles; i++)
+		jlink_clock_data(NULL, 0, &tms, 0, NULL, 0, 1);
+}
 
-	jlink_tap_ensure_space(1, num_cycles + 16);
+static void jlink_runtest(int num_cycles)
+{
+	tap_state_t saved_end_state = tap_get_end_state();
 
 	/* Only do a state_move when we're not already in IDLE. */
 	if (tap_get_state() != TAP_IDLE) {
@@ -702,9 +891,7 @@ static void jlink_runtest(int num_cycles)
 		/* num_cycles--; */
 	}
 
-	/* Execute num_cycles. */
-	for (i = 0; i < num_cycles; i++)
-		jlink_tap_append_step(0, 0);
+	jlink_stableclocks(num_cycles);
 
 	/* Finish in end_state. */
 	jlink_end_state(saved_end_state);
@@ -713,36 +900,6 @@ static void jlink_runtest(int num_cycles)
 		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);
@@ -763,21 +920,25 @@ static void jlink_reset(int trst, int srst)
 
 COMMAND_HANDLER(jlink_usb_command)
 {
+	int tmp;
+
 	if (CMD_ARGC != 1) {
 		command_print(CMD_CTX, "Need exactly one argument for jlink usb.");
 		return ERROR_COMMAND_SYNTAX_ERROR;
 	}
 
-	if (sscanf(CMD_ARGV[0], "%" SCNd8, &usb_address) != 1) {
+	if (sscanf(CMD_ARGV[0], "%i", &tmp) != 1) {
 		command_print(CMD_CTX, "Invalid USB address: %s.", CMD_ARGV[0]);
 		return ERROR_FAIL;
 	}
 
-	if (usb_address > JAYLINK_USB_ADDRESS_3) {
+	if (tmp < JAYLINK_USB_ADDRESS_0 || tmp > JAYLINK_USB_ADDRESS_3) {
 		command_print(CMD_CTX, "Invalid USB address: %s.", CMD_ARGV[0]);
 		return ERROR_FAIL;
 	}
 
+	usb_address = tmp;
+
 	use_serial_number = false;
 	use_usb_address = true;
 
@@ -786,14 +947,22 @@ COMMAND_HANDLER(jlink_usb_command)
 
 COMMAND_HANDLER(jlink_serial_command)
 {
+	int ret;
+
 	if (CMD_ARGC != 1) {
 		command_print(CMD_CTX, "Need exactly one argument for jlink serial.");
 		return ERROR_COMMAND_SYNTAX_ERROR;
 	}
 
-	if (sscanf(CMD_ARGV[0], "%" SCNd32, &serial_number) != 1) {
+	ret = jaylink_parse_serial_number(CMD_ARGV[0], &serial_number);
+
+	if (ret == JAYLINK_ERR) {
 		command_print(CMD_CTX, "Invalid serial number: %s.", CMD_ARGV[0]);
 		return ERROR_FAIL;
+	} else if (ret != JAYLINK_OK) {
+		command_print(CMD_CTX, "jaylink_parse_serial_number() failed: %s.",
+			jaylink_strerror(ret));
+		return ERROR_FAIL;
 	}
 
 	use_serial_number = true;
@@ -811,7 +980,7 @@ COMMAND_HANDLER(jlink_handle_hwstatus_command)
 
 	if (ret != JAYLINK_OK) {
 		command_print(CMD_CTX, "jaylink_get_hardware_status() failed: %s.",
-			jaylink_strerror_name(ret));
+			jaylink_strerror(ret));
 		return ERROR_FAIL;
 	}
 
@@ -843,7 +1012,7 @@ COMMAND_HANDLER(jlink_handle_free_memory_command)
 
 	if (ret != JAYLINK_OK) {
 		command_print(CMD_CTX, "jaylink_get_free_memory() failed: %s.",
-			jaylink_strerror_name(ret));
+			jaylink_strerror(ret));
 		return ERROR_FAIL;
 	}
 
@@ -859,10 +1028,10 @@ COMMAND_HANDLER(jlink_handle_jlink_jtag_command)
 
 	if (!CMD_ARGC) {
 		switch (jtag_command_version) {
-			case JAYLINK_JTAG_V2:
+			case JAYLINK_JTAG_VERSION_2:
 				version = 2;
 				break;
-			case JAYLINK_JTAG_V3:
+			case JAYLINK_JTAG_VERSION_3:
 				version = 3;
 				break;
 			default:
@@ -878,10 +1047,10 @@ COMMAND_HANDLER(jlink_handle_jlink_jtag_command)
 
 		switch (tmp) {
 			case 2:
-				jtag_command_version = JAYLINK_JTAG_V2;
+				jtag_command_version = JAYLINK_JTAG_VERSION_2;
 				break;
 			case 3:
-				jtag_command_version = JAYLINK_JTAG_V3;
+				jtag_command_version = JAYLINK_JTAG_VERSION_3;
 				break;
 			default:
 				command_print(CMD_CTX, "Invalid argument: %s.", CMD_ARGV[0]);
@@ -925,7 +1094,7 @@ COMMAND_HANDLER(jlink_handle_target_power_command)
 
 	if (ret != JAYLINK_OK) {
 		command_print(CMD_CTX, "jaylink_set_target_power() failed: %s.",
-			jaylink_strerror_name(ret));
+			jaylink_strerror(ret));
 		return ERROR_FAIL;
 	}
 
@@ -1031,7 +1200,7 @@ static int poll_trace(uint8_t *buf, size_t *size)
 	ret = jaylink_swo_read(devh, buf, &length);
 
 	if (ret != JAYLINK_OK) {
-		LOG_ERROR("jaylink_swo_read() failed: %s.", jaylink_strerror_name(ret));
+		LOG_ERROR("jaylink_swo_read() failed: %s.", jaylink_strerror(ret));
 		return ERROR_FAIL;
 	}
 
@@ -1052,7 +1221,7 @@ static uint32_t calculate_trace_buffer_size(void)
 
 	if (ret != JAYLINK_OK) {
 		LOG_ERROR("jaylink_get_free_memory() failed: %s.",
-			jaylink_strerror_name(ret));
+			jaylink_strerror(ret));
 		return ERROR_FAIL;
 	}
 
@@ -1064,26 +1233,26 @@ static uint32_t calculate_trace_buffer_size(void)
 	return tmp & 0xffffff00;
 }
 
-static bool check_trace_freq(uint32_t freq, uint32_t div, uint32_t trace_freq)
+static bool check_trace_freq(struct jaylink_swo_speed speed,
+		uint32_t trace_freq)
 {
 	double min;
 	double deviation;
+	uint32_t divider;
 
-	min = fabs(1.0 - (freq / ((double)trace_freq * div)));
+	min = fabs(1.0 - (speed.freq / ((double)trace_freq * speed.min_div)));
 
-	while (freq / div > 0) {
-		deviation = fabs(1.0 - (freq / ((double)trace_freq * div)));
+	for (divider = speed.min_div; divider < speed.max_div; divider++) {
+		deviation = fabs(1.0 - (speed.freq / ((double)trace_freq * divider)));
 
 		if (deviation < 0.03) {
 			LOG_DEBUG("Found suitable frequency divider %u with deviation of "
-				"%.02f %%.", div, deviation);
+				"%.02f %%.", divider, deviation);
 			return true;
 		}
 
 		if (deviation < min)
 			min = deviation;
-
-		div++;
 	}
 
 	LOG_ERROR("Selected trace frequency is not supported by the device. "
@@ -1094,20 +1263,19 @@ static bool check_trace_freq(uint32_t freq, uint32_t div, uint32_t trace_freq)
 	return false;
 }
 
-static int config_trace(bool enabled, enum tpio_pin_protocol pin_protocol,
+static int config_trace(bool enabled, enum tpiu_pin_protocol pin_protocol,
 		uint32_t port_size, unsigned int *trace_freq)
 {
 	int ret;
 	uint32_t buffer_size;
-	uint32_t freq;
-	uint32_t div;
+	struct jaylink_swo_speed speed;
 
 	if (!jaylink_has_cap(caps, JAYLINK_DEV_CAP_SWO)) {
 		LOG_ERROR("Trace capturing is not supported by the device.");
 		return ERROR_FAIL;
 	}
 
-	if (pin_protocol != ASYNC_UART) {
+	if (pin_protocol != TPIU_PIN_PROTOCOL_ASYNC_UART) {
 		LOG_ERROR("Selected pin protocol is not supported.");
 		return ERROR_FAIL;
 	}
@@ -1117,7 +1285,7 @@ static int config_trace(bool enabled, enum tpio_pin_protocol pin_protocol,
 	ret = jaylink_swo_stop(devh);
 
 	if (ret != JAYLINK_OK) {
-		LOG_ERROR("jaylink_swo_stop() failed: %s.", jaylink_strerror_name(ret));
+		LOG_ERROR("jaylink_swo_stop() failed: %s.", jaylink_strerror(ret));
 		return ERROR_FAIL;
 	}
 
@@ -1139,18 +1307,18 @@ static int config_trace(bool enabled, enum tpio_pin_protocol pin_protocol,
 		return ERROR_FAIL;
 	}
 
-	ret = jaylink_swo_get_speeds(devh, JAYLINK_SWO_MODE_UART, &freq, &div);
+	ret = jaylink_swo_get_speeds(devh, JAYLINK_SWO_MODE_UART, &speed);
 
 	if (ret != JAYLINK_OK) {
 		LOG_ERROR("jaylink_swo_get_speeds() failed: %s.",
-			jaylink_strerror_name(ret));
+			jaylink_strerror(ret));
 		return ERROR_FAIL;
 	}
 
 	if (!*trace_freq)
-		*trace_freq = freq / div;
+		*trace_freq = speed.freq / speed.min_div;
 
-	if (!check_trace_freq(freq, div, *trace_freq))
+	if (!check_trace_freq(speed, *trace_freq))
 		return ERROR_FAIL;
 
 	LOG_DEBUG("Using %u bytes device memory for trace capturing.", buffer_size);
@@ -1159,8 +1327,7 @@ static int config_trace(bool enabled, enum tpio_pin_protocol pin_protocol,
 		buffer_size);
 
 	if (ret != JAYLINK_OK) {
-		LOG_ERROR("jaylink_start_swo() failed: %s.",
-			jaylink_strerror_name(ret));
+		LOG_ERROR("jaylink_start_swo() failed: %s.", jaylink_strerror(ret));
 		return ERROR_FAIL;
 	}
 
@@ -1419,7 +1586,7 @@ COMMAND_HANDLER(jlink_handle_config_write_command)
 
 	if (ret != JAYLINK_OK) {
 		LOG_ERROR("jaylink_write_raw_config() failed: %s.",
-			jaylink_strerror_name(ret));
+			jaylink_strerror(ret));
 		return ERROR_FAIL;
 	}
 
@@ -1454,6 +1621,123 @@ COMMAND_HANDLER(jlink_handle_config_command)
 	return ERROR_OK;
 }
 
+COMMAND_HANDLER(jlink_handle_emucom_write_command)
+{
+	int ret;
+	size_t tmp;
+	uint32_t channel;
+	uint32_t length;
+	uint8_t *buf;
+	size_t dummy;
+
+	if (CMD_ARGC != 2)
+		return ERROR_COMMAND_SYNTAX_ERROR;
+
+	if (!jaylink_has_cap(caps, JAYLINK_DEV_CAP_EMUCOM)) {
+		LOG_ERROR("Device does not support EMUCOM.");
+		return ERROR_FAIL;
+	}
+
+	COMMAND_PARSE_NUMBER(u32, CMD_ARGV[0], channel);
+
+	tmp = strlen(CMD_ARGV[1]);
+
+	if (tmp % 2 != 0) {
+		LOG_ERROR("Data must be encoded as hexadecimal pairs.");
+		return ERROR_COMMAND_ARGUMENT_INVALID;
+	}
+
+	buf = malloc(tmp / 2);
+
+	if (!buf) {
+		LOG_ERROR("Failed to allocate buffer.");
+		return ERROR_FAIL;
+	}
+
+	dummy = unhexify(buf, CMD_ARGV[1], tmp / 2);
+
+	if (dummy != (tmp / 2)) {
+		LOG_ERROR("Data must be encoded as hexadecimal pairs.");
+		free(buf);
+		return ERROR_COMMAND_ARGUMENT_INVALID;
+	}
+
+	length = tmp / 2;
+	ret = jaylink_emucom_write(devh, channel, buf, &length);
+
+	free(buf);
+
+	if (ret == JAYLINK_ERR_DEV_NOT_SUPPORTED) {
+		LOG_ERROR("Channel not supported by the device.");
+		return ERROR_FAIL;
+	} else if (ret != JAYLINK_OK) {
+		LOG_ERROR("Failed to write to channel: %s.", jaylink_strerror(ret));
+		return ERROR_FAIL;
+	}
+
+	if (length != (tmp / 2))
+		LOG_WARNING("Only %" PRIu32 " bytes written to the channel.", length);
+
+	return ERROR_OK;
+}
+
+COMMAND_HANDLER(jlink_handle_emucom_read_command)
+{
+	int ret;
+	uint32_t channel;
+	uint32_t length;
+	uint8_t *buf;
+	size_t tmp;
+
+	if (CMD_ARGC != 2)
+		return ERROR_COMMAND_SYNTAX_ERROR;
+
+	if (!jaylink_has_cap(caps, JAYLINK_DEV_CAP_EMUCOM)) {
+		LOG_ERROR("Device does not support EMUCOM.");
+		return ERROR_FAIL;
+	}
+
+	COMMAND_PARSE_NUMBER(u32, CMD_ARGV[0], channel);
+	COMMAND_PARSE_NUMBER(u32, CMD_ARGV[1], length);
+
+	buf = malloc(length * 3 + 1);
+
+	if (!buf) {
+		LOG_ERROR("Failed to allocate buffer.");
+		return ERROR_FAIL;
+	}
+
+	ret = jaylink_emucom_read(devh, channel, buf, &length);
+
+	if (ret == JAYLINK_ERR_DEV_NOT_SUPPORTED) {
+		LOG_ERROR("Channel is not supported by the device.");
+		free(buf);
+		return ERROR_FAIL;
+	} else if (ret == JAYLINK_ERR_DEV_NOT_AVAILABLE) {
+		LOG_ERROR("Channel is not available for the requested amount of data. "
+			"%" PRIu32 " bytes are avilable.", length);
+		free(buf);
+		return ERROR_FAIL;
+	} else if (ret != JAYLINK_OK) {
+		LOG_ERROR("Failed to read from channel: %s.", jaylink_strerror(ret));
+		free(buf);
+		return ERROR_FAIL;
+	}
+
+	tmp = hexify((char *)buf + length, buf, length, 2 * length + 1);
+
+	if (tmp != 2 * length) {
+		LOG_ERROR("Failed to convert data into hexadecimal string.");
+		free(buf);
+		return ERROR_FAIL;
+	}
+
+	command_print(CMD_CTX, "%s", buf + length);
+	free(buf);
+
+	return ERROR_OK;
+}
+
 static const struct command_registration jlink_config_subcommand_handlers[] = {
 	{
 		.name = "usb",
@@ -1499,6 +1783,24 @@ static const struct command_registration jlink_config_subcommand_handlers[] = {
 	COMMAND_REGISTRATION_DONE
 };
 
+static const struct command_registration jlink_emucom_subcommand_handlers[] = {
+	{
+		.name = "write",
+		.handler = &jlink_handle_emucom_write_command,
+		.mode = COMMAND_EXEC,
+		.help = "write to a channel",
+		.usage = "<channel> <data>",
+	},
+	{
+		.name = "read",
+		.handler = &jlink_handle_emucom_read_command,
+		.mode = COMMAND_EXEC,
+		.help = "read from a channel",
+		.usage = "<channel> <length>"
+	},
+	COMMAND_REGISTRATION_DONE
+};
+
 static const struct command_registration jlink_subcommand_handlers[] = {
 	{
 		.name = "jtag",
@@ -1547,6 +1849,14 @@ static const struct command_registration jlink_subcommand_handlers[] = {
 		.help = "access the device configuration. If no argument is given "
 			"this will show the device configuration",
 		.chain = jlink_config_subcommand_handlers,
+		.usage = "[<cmd>]",
+	},
+	{
+		.name = "emucom",
+		.mode = COMMAND_EXEC,
+		.help = "access EMUCOM channel",
+		.chain = jlink_emucom_subcommand_handlers,
+		.usage = "",
 	},
 	COMMAND_REGISTRATION_DONE
 };
@@ -1557,6 +1867,7 @@ static const struct command_registration jlink_command_handlers[] = {
 		.mode = COMMAND_ANY,
 		.help = "perform jlink management",
 		.chain = jlink_subcommand_handlers,
+		.usage = "",
 	},
 	COMMAND_REGISTRATION_DONE
 };
@@ -1568,22 +1879,19 @@ static int jlink_swd_init(void)
 	return ERROR_OK;
 }
 
-static void jlink_swd_write_reg(struct adiv5_dap *dap, uint8_t cmd,
-		uint32_t value)
+static void jlink_swd_write_reg(uint8_t cmd, uint32_t value, uint32_t ap_delay_clk)
 {
 	assert(!(cmd & SWD_CMD_RnW));
-	jlink_swd_queue_cmd(dap, cmd, NULL, value);
+	jlink_swd_queue_cmd(cmd, NULL, value, ap_delay_clk);
 }
 
-static void jlink_swd_read_reg(struct adiv5_dap *dap, uint8_t cmd,
-		uint32_t *value)
+static void jlink_swd_read_reg(uint8_t cmd, uint32_t *value, uint32_t ap_delay_clk)
 {
 	assert(cmd & SWD_CMD_RnW);
-	jlink_swd_queue_cmd(dap, cmd, value, 0);
+	jlink_swd_queue_cmd(cmd, value, 0, ap_delay_clk);
 }
 
-static int_least32_t jlink_swd_frequency(struct adiv5_dap *dap,
-		int_least32_t hz)
+static int_least32_t jlink_swd_frequency(int_least32_t hz)
 {
 	if (hz > 0)
 		jlink_speed(hz / 1000);
@@ -1601,10 +1909,14 @@ 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. */
+	/** First bit position in tdo_buffer to read. */
+	unsigned first;
+	/** Number of bits to read. */
+	unsigned length;
+	/** Location to store the result */
 	void *buffer;
+	/** Offset in the destination buffer */
+	unsigned buffer_offset;
 };
 
 #define MAX_PENDING_SCAN_RESULTS 256
@@ -1616,69 +1928,53 @@ static void jlink_tap_init(void)
 {
 	tap_length = 0;
 	pending_scan_results_length = 0;
+	memset(tms_buffer, 0, sizeof(tms_buffer));
+	memset(tdi_buffer, 0, sizeof(tdi_buffer));
 }
 
-static void jlink_tap_ensure_space(int scans, int bits)
+static void jlink_clock_data(const uint8_t *out, unsigned out_offset,
+			     const uint8_t *tms_out, unsigned tms_offset,
+			     uint8_t *in, unsigned in_offset,
+			     unsigned length)
 {
-	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_var = tap_length / 8;
-
-	assert(index_var < JLINK_TAP_BUFFER_SIZE);
-
-	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_var] = tdi_buffer[index_var] = 0;
-
-	if (tms)
-		tms_buffer[index_var] |= bit;
-	else
-		tms_buffer[index_var] &= ~bit;
-
-	if (tdi)
-		tdi_buffer[index_var] |= bit;
-	else
-		tdi_buffer[index_var] &= ~bit;
+	do {
+		unsigned available_length = JLINK_TAP_BUFFER_SIZE - tap_length / 8;
+
+		if (!available_length ||
+		    (in && pending_scan_results_length == MAX_PENDING_SCAN_RESULTS)) {
+			if (jlink_flush() != ERROR_OK)
+				return;
+			available_length = JLINK_TAP_BUFFER_SIZE;
+		}
 
-	tap_length++;
-}
+		struct pending_scan_result *pending_scan_result =
+			&pending_scan_results_buffer[pending_scan_results_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;
+		unsigned scan_length = length > available_length ?
+			available_length : length;
 
-	pending_scan_result->first = tap_length;
-	pending_scan_result->length = length;
-	pending_scan_result->command = command;
-	pending_scan_result->buffer = buffer;
+		if (out)
+			buf_set_buf(out, out_offset, tdi_buffer, tap_length, scan_length);
+		if (tms_out)
+			buf_set_buf(tms_out, tms_offset, tms_buffer, tap_length, scan_length);
 
-	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);
-	}
+		if (in) {
+			pending_scan_result->first = tap_length;
+			pending_scan_result->length = scan_length;
+			pending_scan_result->buffer = in;
+			pending_scan_result->buffer_offset = in_offset;
+			pending_scan_results_length++;
+		}
 
-	pending_scan_results_length++;
+		tap_length += scan_length;
+		out_offset += scan_length;
+		tms_offset += scan_length;
+		in_offset += scan_length;
+		length -= scan_length;
+	} while (length > 0);
 }
 
-/*
- * 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)
+static int jlink_flush(void)
 {
 	int i;
 	int ret;
@@ -1689,37 +1985,22 @@ static int jlink_tap_execute(void)
 	jlink_last_state = jtag_debug_state_machine(tms_buffer, tdi_buffer,
 		tap_length, jlink_last_state);
 
-	jlink_last_state = jtag_debug_state_machine(tms_buffer, tdi_buffer,
-		tap_length, jlink_last_state);
-
 	ret = jaylink_jtag_io(devh, tms_buffer, tdi_buffer, tdo_buffer,
 		tap_length, jtag_command_version);
 
 	if (ret != JAYLINK_OK) {
-		LOG_ERROR("jaylink_jtag_io() failed: %s.", jaylink_strerror_name(ret));
+		LOG_ERROR("jaylink_jtag_io() failed: %s.", jaylink_strerror(ret));
 		jlink_tap_init();
 		return ERROR_JTAG_QUEUE_FAILED;
 	}
 
 	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);
+		struct pending_scan_result *p = &pending_scan_results_buffer[i];
 
-		if (jtag_read_buffer(buffer, command) != ERROR_OK) {
-			jlink_tap_init();
-			return ERROR_JTAG_QUEUE_FAILED;
-		}
+		buf_set_buf(tdo_buffer, p->first, p->buffer,
+			    p->buffer_offset, p->length);
 
-		if (pending_scan_result->buffer != NULL)
-			free(pending_scan_result->buffer);
+		DEBUG_JTAG_IO("Pending scan result, length = %d.", p->length);
 	}
 
 	jlink_tap_init();
@@ -1762,7 +2043,7 @@ static void jlink_queue_data_in(uint32_t len)
 	tap_length += len;
 }
 
-static int jlink_swd_switch_seq(struct adiv5_dap *dap, enum swd_special_seq seq)
+static int jlink_swd_switch_seq(enum swd_special_seq seq)
 {
 	const uint8_t *s;
 	unsigned int s_len;
@@ -1793,7 +2074,7 @@ static int jlink_swd_switch_seq(struct adiv5_dap *dap, enum swd_special_seq seq)
 	return ERROR_OK;
 }
 
-static int jlink_swd_run_queue(struct adiv5_dap *dap)
+static int jlink_swd_run_queue(void)
 {
 	int i;
 	int ret;
@@ -1814,7 +2095,7 @@ static int jlink_swd_run_queue(struct adiv5_dap *dap)
 	ret = jaylink_swd_io(devh, tms_buffer, tdi_buffer, tdo_buffer, tap_length);
 
 	if (ret != JAYLINK_OK) {
-		LOG_ERROR("jaylink_swd_io() failed: %s.", jaylink_strerror_name(ret));
+		LOG_ERROR("jaylink_swd_io() failed: %s.", jaylink_strerror(ret));
 		goto skip;
 	}
 
@@ -1849,15 +2130,13 @@ skip:
 	return ret;
 }
 
-static void jlink_swd_queue_cmd(struct adiv5_dap *dap, uint8_t cmd,
-		uint32_t *dst, uint32_t data)
+static void jlink_swd_queue_cmd(uint8_t cmd, uint32_t *dst, uint32_t data, uint32_t ap_delay_clk)
 {
 	uint8_t data_parity_trn[DIV_ROUND_UP(32 + 1, 8)];
-
-	if (tap_length + 46 + 8 + dap->memaccess_tck >= swd_buffer_size * 8 ||
-		pending_scan_results_length == MAX_PENDING_SCAN_RESULTS) {
+	if (tap_length + 46 + 8 + ap_delay_clk >= swd_buffer_size * 8 ||
+	    pending_scan_results_length == MAX_PENDING_SCAN_RESULTS) {
 		/* Not enough room in the queue. Run the queue. */
-		queued_retval = jlink_swd_run_queue(dap);
+		queued_retval = jlink_swd_run_queue();
 	}
 
 	if (queued_retval != ERROR_OK)
@@ -1890,7 +2169,7 @@ static void jlink_swd_queue_cmd(struct adiv5_dap *dap, uint8_t cmd,
 
 	/* Insert idle cycles after AP accesses to avoid WAIT. */
 	if (cmd & SWD_CMD_APnDP)
-		jlink_queue_data_out(NULL, dap->memaccess_tck);
+		jlink_queue_data_out(NULL, ap_delay_clk);
 }
 
 static const struct swd_driver jlink_swd = {