- calculate cycles since last executed instruction when cycle-accurate tracing is enabled

- increase memory pseudo-image cache size to 1024 byte for improved trace analysis performance
- added OpenOCD+trace as an ETM capture driver example implementation
- new usbprog driver (thanks to Benedikt Sauter)


git-svn-id: svn://svn.berlios.de/openocd/trunk@186 b42882b7-edfa-0310-969c-e2dbd0fdcd60

6 files changed, 666 insertions, 11 deletions

diff --git a/src/target/Makefile.am b/src/target/Makefile.am
index d33d161b..c2aa65b4 100644
--- a/src/target/Makefile.am
+++ b/src/target/Makefile.am
@@ -1,11 +1,18 @@
+
+if OOCD_TRACE
+OOCD_TRACE_FILES = oocd_trace.c
+else
+OOCD_TRACE_FILES =
+endif
+
 INCLUDES = -I$(top_srcdir)/src/gdb -I$(top_srcdir)/src/helper 	-I$(top_srcdir)/src/jtag -I$(top_srcdir)/src/xsvf $(all_includes)
 METASOURCES = AUTO
 noinst_LIBRARIES = libtarget.a
 libtarget_a_SOURCES = target.c register.c breakpoints.c armv4_5.c embeddedice.c etm.c arm7tdmi.c arm9tdmi.c \
 	arm_jtag.c arm7_9_common.c algorithm.c arm920t.c arm720t.c armv4_5_mmu.c armv4_5_cache.c arm_disassembler.c \
 	arm966e.c arm926ejs.c etb.c xscale.c arm_simulator.c image.c armv7m.c cortex_m3.c cortex_swjdp.c \
-	etm_dummy.c
+	etm_dummy.c $(OOCD_TRACE_FILES)
 noinst_HEADERS = target.h register.h armv4_5.h embeddedice.h etm.h arm7tdmi.h arm9tdmi.h \
 	arm_jtag.h arm7_9_common.h arm920t.h arm720t.h armv4_5_mmu.h armv4_5_cache.h breakpoints.h algorithm.h \
 	arm_disassembler.h arm966e.h arm926ejs.h etb.h xscale.h arm_simulator.h image.h armv7m.h cortex_m3.h cortex_swjdp.h \
-	etm_dummy.h
+	etm_dummy.h oocd_trace.h
diff --git a/src/target/etm.c b/src/target/etm.c
index e095e50d..52e4b3d6 100644
--- a/src/target/etm.c
+++ b/src/target/etm.c
@@ -285,12 +285,12 @@ reg_cache_t* etm_build_reg_cache(target_t *target, arm_jtag_t *jtag_info, etm_co
 		reg_cache->next = etb_build_reg_cache(etb);
 		
 		etb->reg_cache = reg_cache->next;
-		
-		if (etm_ctx->capture_driver->init(etm_ctx) != ERROR_OK)
-		{
-			ERROR("ETM capture driver initialization failed");
-			exit(-1);
-		}
+	}
+	
+	if (etm_ctx->capture_driver->init(etm_ctx) != ERROR_OK)
+	{
+		ERROR("ETM capture driver initialization failed");
+		exit(-1);
 	}
 	
 	return reg_cache;
@@ -466,11 +466,17 @@ int etm_store_reg(reg_t *reg)
  */
 extern etm_capture_driver_t etb_capture_driver;
 extern etm_capture_driver_t etm_dummy_capture_driver;
+#if BUILD_OOCD_TRACE == 1
+extern etm_capture_driver_t oocd_trace_capture_driver;
+#endif
 
 etm_capture_driver_t *etm_capture_drivers[] = 
 {
 	&etb_capture_driver,
 	&etm_dummy_capture_driver,
+#if BUILD_OOCD_TRACE == 1
+	&oocd_trace_capture_driver,
+#endif
 	NULL
 };
 
@@ -753,6 +759,8 @@ int etmv1_analyze_trace(etm_context_t *ctx, struct command_context_s *cmd_ctx)
 		u32 next_pc = ctx->current_pc;
 		u32 old_data_index = ctx->data_index;
 		u32 old_data_half = ctx->data_half;
+		u32 old_index = ctx->pipe_index;
+		u32 cycles = 0;
 		
 		if (ctx->trace_data[ctx->pipe_index].flags & ETMV1_TRIGGER_CYCLE)
 		{
@@ -762,6 +770,8 @@ int etmv1_analyze_trace(etm_context_t *ctx, struct command_context_s *cmd_ctx)
 		/* if we don't have a valid pc skip until we reach an indirect branch */
 		if ((!ctx->pc_ok) && (pipestat != STAT_BE))
 		{
+			if (pipestat == STAT_IE)
+				ctx->last_instruction = ctx->pipe_index;
 			ctx->pipe_index++;
 			continue;
 		}
@@ -800,27 +810,32 @@ int etmv1_analyze_trace(etm_context_t *ctx, struct command_context_s *cmd_ctx)
 			{
 				case 0x0:	/* normal PC change */
 					next_pc = ctx->last_branch;
+					ctx->last_instruction = old_index;
 					break;
 				case 0x1:	/* tracing enabled */
 					command_print(cmd_ctx, "--- tracing enabled at 0x%8.8x ---", ctx->last_branch);
 					ctx->current_pc = ctx->last_branch;
 					ctx->pipe_index++;
+					ctx->last_instruction = old_index;
 					continue;
 					break;
 				case 0x2:	/* trace restarted after FIFO overflow */
 					command_print(cmd_ctx, "--- trace restarted after FIFO overflow at 0x%8.8x ---", ctx->last_branch);
 					ctx->current_pc = ctx->last_branch;
 					ctx->pipe_index++;
+					ctx->last_instruction = old_index;
 					continue;
 					break;
 				case 0x3:	/* exit from debug state */
 					command_print(cmd_ctx, "--- exit from debug state at 0x%8.8x ---", ctx->last_branch);
 					ctx->current_pc = ctx->last_branch;
 					ctx->pipe_index++;
+					ctx->last_instruction = old_index;
 					continue;
 					break;
 				case 0x4:	/* periodic synchronization point */
 					next_pc = ctx->last_branch;
+					ctx->last_instruction = old_index;
 					break;
 				default:	/* reserved */
 					ERROR("BUG: branch reason code 0x%x is reserved", ctx->last_branch_reason);		
@@ -839,6 +854,8 @@ int etmv1_analyze_trace(etm_context_t *ctx, struct command_context_s *cmd_ctx)
 			if (((ctx->last_branch >= 0x0) && (ctx->last_branch <= 0x20))
 				|| ((ctx->last_branch >= 0xffff0000) && (ctx->last_branch <= 0xffff0020)))
 			{
+				ctx->last_instruction = old_index;
+				
 				if ((ctx->last_branch & 0xff) == 0x10)
 				{
 					command_print(cmd_ctx, "data abort");
@@ -871,6 +888,9 @@ int etmv1_analyze_trace(etm_context_t *ctx, struct command_context_s *cmd_ctx)
 					/* TODO: handle incomplete images */
 				}
 			}
+			
+			cycles = old_index - ctx->last_instruction;
+			ctx->last_instruction = old_index;
 		}
 		
 		if ((pipestat == STAT_ID) || (pipestat == STAT_BD))
@@ -963,8 +983,22 @@ int etmv1_analyze_trace(etm_context_t *ctx, struct command_context_s *cmd_ctx)
 
 		if ((pipestat != STAT_TD) && (pipestat != STAT_WT))
 		{
-			command_print(cmd_ctx, "%s%s",
-				instruction.text, (pipestat == STAT_IN) ? " (not executed)" : "");
+			char cycles_text[32] = "";
+			
+			/* if the trace was captured with cycle accurate tracing enabled,
+			 * output the number of cycles since the last executed instruction
+			 */
+			if (ctx->tracemode & ETMV1_CYCLE_ACCURATE)
+			{
+				snprintf(cycles_text, 32, " (%i %s)",
+					cycles,
+					(cycles == 1) ? "cycle" : "cycles");
+			}
+			
+			command_print(cmd_ctx, "%s%s%s",
+				instruction.text,
+				(pipestat == STAT_IN) ? " (not executed)" : "",
+				cycles_text);
 
 			ctx->current_pc = next_pc;
 			
@@ -1265,6 +1299,7 @@ int handle_etm_config_command(struct command_context_s *cmd_ctx, char *cmd, char
 	}
 	
 	etm_ctx->target = target;
+	etm_ctx->trigger_percent = 50;
 	etm_ctx->trace_data = NULL;
 	etm_ctx->trace_depth = 0;
 	etm_ctx->portmode = portmode;
@@ -1280,6 +1315,7 @@ int handle_etm_config_command(struct command_context_s *cmd_ctx, char *cmd, char
 	etm_ctx->last_ptr = 0x0;
 	etm_ctx->ptr_ok = 0x0;
 	etm_ctx->context_id = 0x0;
+	etm_ctx->last_instruction = 0;
 	
 	arm7_9->etm_ctx = etm_ctx;
 	
@@ -1288,6 +1324,78 @@ int handle_etm_config_command(struct command_context_s *cmd_ctx, char *cmd, char
 	return ERROR_OK;
 }
 
+int handle_etm_info_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
+{
+	target_t *target;
+	armv4_5_common_t *armv4_5;
+	arm7_9_common_t *arm7_9;
+	reg_t *etm_config_reg;
+	reg_t *etm_sys_config_reg;
+	
+	int max_port_size;
+		
+	target = get_current_target(cmd_ctx);
+	
+	if (arm7_9_get_arch_pointers(target, &armv4_5, &arm7_9) != ERROR_OK)
+	{
+		command_print(cmd_ctx, "current target isn't an ARM7/ARM9 target");
+		return ERROR_OK;
+	}
+	
+	if (!arm7_9->etm_ctx)
+	{
+		command_print(cmd_ctx, "current target doesn't have an ETM configured");
+		return ERROR_OK;
+	}
+	
+	etm_config_reg = &arm7_9->etm_ctx->reg_cache->reg_list[ETM_CONFIG];
+	etm_sys_config_reg = &arm7_9->etm_ctx->reg_cache->reg_list[ETM_SYS_CONFIG];
+	
+	etm_get_reg(etm_config_reg);
+	command_print(cmd_ctx, "pairs of address comparators: %i", buf_get_u32(etm_config_reg->value, 0, 4));
+	command_print(cmd_ctx, "pairs of data comparators: %i", buf_get_u32(etm_config_reg->value, 4, 4));
+	command_print(cmd_ctx, "memory map decoders: %i", buf_get_u32(etm_config_reg->value, 8, 4));
+	command_print(cmd_ctx, "number of counters: %i", buf_get_u32(etm_config_reg->value, 12, 4));
+	command_print(cmd_ctx, "sequencer %spresent",
+			(buf_get_u32(etm_config_reg->value, 16, 1) == 1) ? "" : "not ");
+	command_print(cmd_ctx, "number of ext. inputs: %i", buf_get_u32(etm_config_reg->value, 17, 3));
+	command_print(cmd_ctx, "number of ext. outputs: %i", buf_get_u32(etm_config_reg->value, 20, 3));
+	command_print(cmd_ctx, "FIFO full %spresent",
+			(buf_get_u32(etm_config_reg->value, 23, 1) == 1) ? "" : "not ");
+	command_print(cmd_ctx, "protocol version: %i", buf_get_u32(etm_config_reg->value, 28, 3));
+	
+	etm_get_reg(etm_sys_config_reg);
+
+	switch (buf_get_u32(etm_sys_config_reg->value, 0, 3))
+	{
+		case 0:
+			max_port_size = 4;
+			break;
+		case 1:
+			max_port_size = 8;
+			break;
+		case 2:
+			max_port_size = 16;
+			break;
+	}
+	command_print(cmd_ctx, "max. port size: %i", max_port_size);
+	
+	command_print(cmd_ctx, "half-rate clocking %ssupported",
+			(buf_get_u32(etm_sys_config_reg->value, 3, 1) == 1) ? "" : "not ");
+	command_print(cmd_ctx, "full-rate clocking %ssupported",
+			(buf_get_u32(etm_sys_config_reg->value, 4, 1) == 1) ? "" : "not ");
+	command_print(cmd_ctx, "normal trace format %ssupported",
+			(buf_get_u32(etm_sys_config_reg->value, 5, 1) == 1) ? "" : "not ");
+	command_print(cmd_ctx, "multiplex trace format %ssupported",
+			(buf_get_u32(etm_sys_config_reg->value, 6, 1) == 1) ? "" : "not ");
+	command_print(cmd_ctx, "demultiplex trace format %ssupported",
+			(buf_get_u32(etm_sys_config_reg->value, 7, 1) == 1) ? "" : "not ");
+	command_print(cmd_ctx, "FIFO full %ssupported",
+			(buf_get_u32(etm_sys_config_reg->value, 8, 1) == 1) ? "" : "not ");
+	
+	return ERROR_OK;
+}
+
 int handle_etm_status_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
 {
 	target_t *target;
@@ -1540,6 +1648,46 @@ int handle_etm_load_command(struct command_context_s *cmd_ctx, char *cmd, char *
 	return ERROR_OK;	
 }
 
+int handle_etm_trigger_percent_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
+{
+	target_t *target;
+	armv4_5_common_t *armv4_5;
+	arm7_9_common_t *arm7_9;
+	etm_context_t *etm_ctx;
+	
+	target = get_current_target(cmd_ctx);
+	
+	if (arm7_9_get_arch_pointers(target, &armv4_5, &arm7_9) != ERROR_OK)
+	{
+		command_print(cmd_ctx, "current target isn't an ARM7/ARM9 target");
+		return ERROR_OK;
+	}
+	
+	if (!(etm_ctx = arm7_9->etm_ctx))
+	{
+		command_print(cmd_ctx, "current target doesn't have an ETM configured");
+		return ERROR_OK;
+	}
+	
+	if (argc > 0)
+	{
+		u32 new_value = strtoul(args[0], NULL, 0);
+		
+		if ((new_value < 2) || (new_value > 100))
+		{
+			command_print(cmd_ctx, "valid settings are 2% to 100%");
+		}
+		else
+		{
+			etm_ctx->trigger_percent = new_value;
+		}
+	}
+	
+	command_print(cmd_ctx, "%i percent of the tracebuffer reserved for after the trigger", etm_ctx->trigger_percent);
+
+	return ERROR_OK;
+}
+
 int handle_etm_start_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
 {
 	target_t *target;
@@ -1660,6 +1808,11 @@ int etm_register_user_commands(struct command_context_s *cmd_ctx)
 	register_command(cmd_ctx, etm_cmd, "tracemode", handle_etm_tracemode_command,
 		COMMAND_EXEC, "configure trace mode <none|data|address|all> <context id bits> <cycle accurate> <branch output");
 
+	register_command(cmd_ctx, etm_cmd, "info", handle_etm_info_command,
+		COMMAND_EXEC, "display info about the current target's ETM");
+
+	register_command(cmd_ctx, etm_cmd, "trigger_percent <percent>", handle_etm_trigger_percent_command,
+		COMMAND_EXEC, "amount (<percent>) of trace buffer to be filled after the trigger occured");
 	register_command(cmd_ctx, etm_cmd, "status", handle_etm_status_command,
 		COMMAND_EXEC, "display current target's ETM status");
 	register_command(cmd_ctx, etm_cmd, "start", handle_etm_start_command,
diff --git a/src/target/etm.h b/src/target/etm.h
index f5a48c31..bcaf2513 100644
--- a/src/target/etm.h
+++ b/src/target/etm.h
@@ -145,6 +145,7 @@ typedef struct etm_context_s
 	reg_cache_t *reg_cache;			/* ETM register cache */

 	etm_capture_driver_t *capture_driver;	/* driver used to access ETM data */

 	void *capture_driver_priv;		/* capture driver private data */

+	u32 trigger_percent;			/* percent of trace buffer to be filled after the trigger */

 	trace_status_t capture_status;	/* current state of capture run */ 

 	etmv1_trace_data_t *trace_data;	/* trace data */

 	u32 trace_depth;				/* number of trace cycles to be analyzed, 0 if no trace data available */

@@ -162,6 +163,7 @@ typedef struct etm_context_s
 	u32 last_ptr;					/* address of the last data access */

 	u32 ptr_ok;						/* whether last_ptr is valid */ 

 	u32 context_id;					/* context ID of the code being traced */

+	u32 last_instruction;			/* index of last instruction executed (to calculate cycle timings) */

 } etm_context_t;

 

 /* PIPESTAT values */

diff --git a/src/target/image.h b/src/target/image.h
index d741ab96..2e4ef968 100644
--- a/src/target/image.h
+++ b/src/target/image.h
@@ -34,7 +34,7 @@
 #define IMAGE_MAX_ERROR_STRING		(256)
 #define IMAGE_MAX_SECTIONS			(128)
 
-#define IMAGE_MEMORY_CACHE_SIZE		(128)
+#define IMAGE_MEMORY_CACHE_SIZE		(1024)
 
 typedef enum image_type
 {
diff --git a/src/target/oocd_trace.c b/src/target/oocd_trace.c
new file mode 100644
index 00000000..ff63820a
--- /dev/null
+++ b/src/target/oocd_trace.c
@@ -0,0 +1,429 @@
+/***************************************************************************
+ *   Copyright (C) 2007 by Dominic Rath                                    *
+ *   Dominic.Rath@gmx.de                                                   *
+ *                                                                         *
+ *   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 <string.h>
+#include <errno.h>
+
+#include "oocd_trace.h"
+#include "etm.h"
+
+#include "log.h"
+#include "types.h"
+#include "binarybuffer.h"
+#include "target.h"
+#include "register.h"
+#include "jtag.h"
+#include "arm7_9_common.h"
+
+#include <stdlib.h>
+
+int oocd_trace_read_reg(oocd_trace_t *oocd_trace, int reg, u32 *value)
+{
+	size_t bytes_written, bytes_read, bytes_to_read;
+	u8 cmd;
+
+	cmd = 0x10 | (reg & 0x7);
+	bytes_written = write(oocd_trace->tty_fd, &cmd, 1);
+
+	bytes_to_read = 4;
+	while (bytes_to_read > 0)
+	{
+		bytes_read = read(oocd_trace->tty_fd, ((u8*)value) + 4 - bytes_to_read, bytes_to_read);
+		bytes_to_read -= bytes_read;
+	}
+
+	DEBUG("reg #%i: 0x%8.8x\n", reg, *value);
+	
+	return ERROR_OK;
+}
+
+int oocd_trace_write_reg(oocd_trace_t *oocd_trace, int reg, u32 value)
+{
+    size_t bytes_written;
+    u8 data[5];
+
+    data[0] = 0x18 | (reg & 0x7);
+    data[1] = value & 0xff;
+    data[2] = (value & 0xff00) >> 8;
+    data[3] = (value & 0xff0000) >> 16;
+    data[4] = (value & 0xff000000) >> 24;
+
+    bytes_written = write(oocd_trace->tty_fd, data, 5);
+    DEBUG("reg #%i: 0x%8.8x\n", reg, value);
+
+    return ERROR_OK;
+}
+
+int oocd_trace_read_memory(oocd_trace_t *oocd_trace, u8 *data, u32 address, u32 size)
+{
+	size_t bytes_written, bytes_read, bytes_to_read;
+	u8 cmd;
+	int i;
+
+	oocd_trace_write_reg(oocd_trace, OOCD_TRACE_ADDRESS, address);
+	oocd_trace_write_reg(oocd_trace, OOCD_TRACE_SDRAM_COUNTER, size);
+
+	cmd = 0x20;
+	bytes_written = write(oocd_trace->tty_fd, &cmd, 1);
+
+	bytes_to_read = size * 16;
+	while (bytes_to_read > 0)
+	{
+		if ((bytes_read = read(oocd_trace->tty_fd,
+				((u8*)data) + (size * 16) - bytes_to_read, bytes_to_read)) < 0)
+		{
+			DEBUG("read() returned %i (%s)", bytes_read, strerror(errno));
+		}
+		else
+			bytes_to_read -= bytes_read;
+	}
+	
+	return ERROR_OK;
+}
+
+int oocd_trace_init(etm_context_t *etm_ctx)
+{
+	u8 trash[256];
+	oocd_trace_t *oocd_trace = etm_ctx->capture_driver_priv;
+	size_t bytes_written, bytes_read, bytes_to_read;
+	
+	oocd_trace->tty_fd = open(oocd_trace->tty, O_RDWR | O_NOCTTY | O_NONBLOCK);
+
+	if(oocd_trace->tty_fd < 0)
+	{
+		ERROR("can't open tty");
+		return ERROR_ETM_CAPTURE_INIT_FAILED;
+	}
+
+	/* clear input & output buffers, then switch to "blocking mode" */
+	tcflush(oocd_trace->tty_fd, TCOFLUSH);
+	tcflush(oocd_trace->tty_fd, TCIFLUSH);
+	fcntl(oocd_trace->tty_fd, F_SETFL, fcntl(oocd_trace->tty_fd, F_GETFL) & ~O_NONBLOCK);
+	
+	tcgetattr(oocd_trace->tty_fd, &oocd_trace->oldtio); /* save current port settings */
+	
+	bzero(&oocd_trace->newtio, sizeof(oocd_trace->newtio));
+	oocd_trace->newtio.c_cflag = CS8 | CLOCAL | CREAD | B2500000;
+	
+	oocd_trace->newtio.c_iflag = IGNPAR | IGNBRK | IXON | IXOFF;
+	oocd_trace->newtio.c_oflag = 0;
+	
+	/* set input mode (non-canonical, no echo,...) */
+	oocd_trace->newtio.c_lflag = 0;
+	
+	cfmakeraw(&oocd_trace->newtio);
+	oocd_trace->newtio.c_cc[VTIME] = 1;   /* inter-character timer used */
+	oocd_trace->newtio.c_cc[VMIN] = 0;   /* blocking read until 0 chars received */
+	
+	tcflush(oocd_trace->tty_fd, TCIFLUSH);
+	tcsetattr(oocd_trace->tty_fd, TCSANOW, &oocd_trace->newtio);
+	
+	/* occasionally one bogus character is left in the input buffer
+	 * read up any leftover characters to ensure communication is in sync */
+	while ((bytes_read = read(oocd_trace->tty_fd, trash, sizeof(trash))) > 0)
+	{
+	    DEBUG("%i bytes read\n", bytes_read);
+	};
+	
+	return ERROR_OK;
+}
+
+trace_status_t oocd_trace_status(etm_context_t *etm_ctx)
+{
+	oocd_trace_t *oocd_trace = etm_ctx->capture_driver_priv;
+	u32 status;
+	
+	oocd_trace_read_reg(oocd_trace, OOCD_TRACE_STATUS, &status);
+	
+	/* if tracing is currently idle, return this information */
+	if (etm_ctx->capture_status == TRACE_IDLE)
+	{
+		return etm_ctx->capture_status;
+	}
+	else if (etm_ctx->capture_status & TRACE_RUNNING)
+	{
+		/* check Full bit to identify an overflow */
+		if (status & 0x4)
+			etm_ctx->capture_status |= TRACE_OVERFLOWED;
+		
+		/* check Triggered bit to identify trigger condition */
+		if (status & 0x2)
+			etm_ctx->capture_status |= TRACE_TRIGGERED;
+		
+		if (status & 0x1)
+		{
+			etm_ctx->capture_status &= ~TRACE_RUNNING;
+			etm_ctx->capture_status |= TRACE_COMPLETED;
+		}
+	}
+	
+	return etm_ctx->capture_status;
+}
+
+int oocd_trace_read_trace(etm_context_t *etm_ctx)
+{
+	oocd_trace_t *oocd_trace = etm_ctx->capture_driver_priv;
+	u32 status, address;
+	u32 first_frame = 0x0;
+	u32 num_frames = 1048576;
+	u8 *trace_data;
+	int i;
+
+    oocd_trace_read_reg(oocd_trace, OOCD_TRACE_STATUS, &status);
+    oocd_trace_read_reg(oocd_trace, OOCD_TRACE_ADDRESS, &address);
+
+	/* check if we overflowed, and adjust first frame of the trace accordingly
+	 * if we didn't overflow, read only up to the frame that would be written next,
+	 * i.e. don't read invalid entries
+	 */
+	if (status & 0x4)
+		first_frame = address;
+	else
+		num_frames = address;
+
+	/* read data into temporary array for unpacking 
+	 * one frame from OpenOCD+trace corresponds to 16 trace cycles
+	 */
+	trace_data = malloc(sizeof(u8) * num_frames * 16);
+	oocd_trace_read_memory(oocd_trace, trace_data, first_frame, num_frames);
+
+	if (etm_ctx->trace_depth > 0)
+	{
+		free(etm_ctx->trace_data);
+	}
+
+	etm_ctx->trace_depth = num_frames * 16;
+	etm_ctx->trace_data = malloc(sizeof(etmv1_trace_data_t) * etm_ctx->trace_depth);
+	
+	for (i = 0; i < num_frames * 16; i++)
+	{
+		etm_ctx->trace_data[i].pipestat = (trace_data[i] & 0x7);
+		etm_ctx->trace_data[i].packet = (trace_data[i] & 0x78) >> 3;
+		etm_ctx->trace_data[i].flags = 0;
+		
+		if ((trace_data[i] & 0x80) >> 7)
+		{
+			etm_ctx->trace_data[i].flags |= ETMV1_TRACESYNC_CYCLE;
+		}
+
+		if (etm_ctx->trace_data[i].pipestat == STAT_TR)
+		{
+			etm_ctx->trace_data[i].pipestat = etm_ctx->trace_data[i].packet & 0x7;
+			etm_ctx->trace_data[i].flags |= ETMV1_TRIGGER_CYCLE;
+		}
+	}
+	
+	free(trace_data);
+
+	return ERROR_OK;
+}
+
+int oocd_trace_start_capture(etm_context_t *etm_ctx)
+{
+	oocd_trace_t *oocd_trace = etm_ctx->capture_driver_priv;
+	u32 control = 0x1;	/* 0x1: enabled */
+	u32 trigger_count;
+	
+	if (((etm_ctx->portmode & ETM_PORT_MODE_MASK) != ETM_PORT_NORMAL)
+		|| ((etm_ctx->portmode & ETM_PORT_WIDTH_MASK) != ETM_PORT_4BIT))
+	{
+		DEBUG("OpenOCD+trace only supports normal 4-bit ETM mode");
+		return ERROR_ETM_PORTMODE_NOT_SUPPORTED;
+	}
+	
+	if ((etm_ctx->portmode & ETM_PORT_CLOCK_MASK) == ETM_PORT_HALF_CLOCK)
+	{
+		control |= 0x2;	/* half rate clock, capture at twice the clock rate */
+	}
+	
+	/* OpenOCD+trace holds up to 16 million samples,
+	 * but trigger counts is set in multiples of 16 */
+	trigger_count = (1048576 * etm_ctx->trigger_percent) / 100;
+
+	/* capturing always starts at address zero */
+	oocd_trace_write_reg(oocd_trace, OOCD_TRACE_ADDRESS, 0x0);
+	oocd_trace_write_reg(oocd_trace, OOCD_TRACE_TRIGGER_COUNTER, trigger_count);
+	oocd_trace_write_reg(oocd_trace, OOCD_TRACE_CONTROL, control);
+	
+	/* we're starting a new trace, initialize capture status */
+	etm_ctx->capture_status = TRACE_RUNNING;
+	
+	return ERROR_OK; 
+}
+
+int oocd_trace_stop_capture(etm_context_t *etm_ctx)
+{
+	oocd_trace_t *oocd_trace = etm_ctx->capture_driver_priv;
+
+	/* trace stopped, just clear running flag, but preserve others */ 
+	etm_ctx->capture_status &= ~TRACE_RUNNING;
+	
+	oocd_trace_write_reg(oocd_trace, OOCD_TRACE_CONTROL, 0x0);
+	
+	return ERROR_OK;
+}
+
+etm_capture_driver_t oocd_trace_capture_driver =
+{
+	.name = "oocd_trace",
+	.register_commands = oocd_trace_register_commands,
+	.init = oocd_trace_init,
+	.status = oocd_trace_status,
+	.start_capture = oocd_trace_start_capture,
+	.stop_capture = oocd_trace_stop_capture,
+	.read_trace = oocd_trace_read_trace,
+};
+
+int handle_oocd_trace_config_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
+{
+	target_t *target;
+	armv4_5_common_t *armv4_5;
+	arm7_9_common_t *arm7_9;
+	
+	if (argc != 2)
+	{
+		ERROR("incomplete 'oocd_trace config <target> <tty>' command");
+		exit(-1);
+	}
+	
+	target = get_current_target(cmd_ctx);
+	
+	if (arm7_9_get_arch_pointers(target, &armv4_5, &arm7_9) != ERROR_OK)
+	{
+		command_print(cmd_ctx, "current target isn't an ARM7/ARM9 target");
+		return ERROR_OK;
+	}
+	
+	if (arm7_9->etm_ctx)
+	{
+		oocd_trace_t *oocd_trace = malloc(sizeof(oocd_trace_t));
+		
+		arm7_9->etm_ctx->capture_driver_priv = oocd_trace;
+		oocd_trace->etm_ctx = arm7_9->etm_ctx;
+		
+		/* copy name of TTY device used to communicate with OpenOCD+trace */
+		oocd_trace->tty = strndup(args[1], 256);
+	}
+	else
+	{
+		ERROR("target has no ETM defined, OpenOCD+trace left unconfigured");
+	}
+
+	return ERROR_OK;
+}
+
+int handle_oocd_trace_status_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
+{
+	target_t *target;
+	armv4_5_common_t *armv4_5;
+	arm7_9_common_t *arm7_9;
+	oocd_trace_t *oocd_trace;
+	u32 status;
+	
+	target = get_current_target(cmd_ctx);
+	
+	if (arm7_9_get_arch_pointers(target, &armv4_5, &arm7_9) != ERROR_OK)
+	{
+		command_print(cmd_ctx, "current target isn't an ARM7/ARM9 target");
+		return ERROR_OK;
+	}
+	
+	if (!arm7_9->etm_ctx)
+	{
+		command_print(cmd_ctx, "current target doesn't have an ETM configured");
+		return ERROR_OK;
+	}
+	
+	if (strcmp(arm7_9->etm_ctx->capture_driver->name, "oocd_trace") != 0)
+	{
+		command_print(cmd_ctx, "current target's ETM capture driver isn't 'oocd_trace'");
+		return ERROR_OK;
+	}
+	
+	oocd_trace = (oocd_trace_t*)arm7_9->etm_ctx->capture_driver_priv;
+	
+	oocd_trace_read_reg(oocd_trace, OOCD_TRACE_STATUS, &status);
+	
+	if (status & 0x8)
+		command_print(cmd_ctx, "trace clock locked");
+	else
+		command_print(cmd_ctx, "no trace clock");
+		
+	return ERROR_OK;
+}
+
+int handle_oocd_trace_resync_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
+{
+	target_t *target;
+	armv4_5_common_t *armv4_5;
+	arm7_9_common_t *arm7_9;
+	oocd_trace_t *oocd_trace;
+	u32 status;
+	size_t bytes_written;
+	u8 cmd_array[1];
+	
+	target = get_current_target(cmd_ctx);
+	
+	if (arm7_9_get_arch_pointers(target, &armv4_5, &arm7_9) != ERROR_OK)
+	{
+		command_print(cmd_ctx, "current target isn't an ARM7/ARM9 target");
+		return ERROR_OK;
+	}
+	
+	if (!arm7_9->etm_ctx)
+	{
+		command_print(cmd_ctx, "current target doesn't have an ETM configured");
+		return ERROR_OK;
+	}
+	
+	if (strcmp(arm7_9->etm_ctx->capture_driver->name, "oocd_trace") != 0)
+	{
+		command_print(cmd_ctx, "current target's ETM capture driver isn't 'oocd_trace'");
+		return ERROR_OK;
+	}
+	
+	oocd_trace = (oocd_trace_t*)arm7_9->etm_ctx->capture_driver_priv;
+	
+	cmd_array[0] = 0xf0;
+
+	bytes_written = write(oocd_trace->tty_fd, cmd_array, 1);
+	
+	command_print(cmd_ctx, "requesting traceclock resync");
+	DEBUG("resyncing traceclk pll");
+
+	return ERROR_OK;
+}
+
+int oocd_trace_register_commands(struct command_context_s *cmd_ctx)
+{
+	command_t *oocd_trace_cmd;
+	
+	oocd_trace_cmd = register_command(cmd_ctx, NULL, "oocd_trace", NULL, COMMAND_ANY, "OpenOCD+trace");
+	
+	register_command(cmd_ctx, oocd_trace_cmd, "config", handle_oocd_trace_config_command, COMMAND_CONFIG, NULL);
+
+	register_command(cmd_ctx, oocd_trace_cmd, "status", handle_oocd_trace_status_command, COMMAND_EXEC, "display OpenOCD+trace status");
+	register_command(cmd_ctx, oocd_trace_cmd, "resync", handle_oocd_trace_resync_command, COMMAND_EXEC, "resync OpenOCD+trace capture clock");
+
+	return ERROR_OK;
+}
diff --git a/src/target/oocd_trace.h b/src/target/oocd_trace.h
new file mode 100644
index 00000000..c80a7ced
--- /dev/null
+++ b/src/target/oocd_trace.h
@@ -0,0 +1,64 @@
+/***************************************************************************

+ *   Copyright (C) 2007 by Dominic Rath                                    *

+ *   Dominic.Rath@gmx.de                                                   *

+ *                                                                         *

+ *   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.             *

+ ***************************************************************************/

+#ifndef OOCD_TRACE_H

+#define OOCD_TRACE_H

+

+#include "command.h"

+

+#include "etm.h"

+

+#include <termios.h>

+#include <unistd.h>

+

+/* registers */

+enum

+{

+    OOCD_TRACE_ID = 0x7,

+    OOCD_TRACE_ADDRESS = 0x0,

+    OOCD_TRACE_TRIGGER_COUNTER = 0x01,

+    OOCD_TRACE_CONTROL = 0x2,

+    OOCD_TRACE_STATUS = 0x3,

+    OOCD_TRACE_SDRAM_COUNTER = 0x4,

+};

+

+/* commands */

+enum

+{

+	OOCD_TRACE_NOP = 0x0,

+	OOCD_TRACE_READ_REG = 0x10,

+	OOCD_TRACE_WRITE_REG = 0x18,

+	OOCD_TRACE_READ_RAM = 0x20,

+/*	OOCD_TRACE_WRITE_RAM = 0x28, */

+	OOCD_TRACE_RESYNC = 0xf0,

+};

+

+typedef struct oocd_trace_s

+{

+	etm_context_t *etm_ctx;

+	char *tty;

+	int tty_fd;

+	struct termios oldtio, newtio;

+} oocd_trace_t;

+

+extern etm_capture_driver_t oocd_trace_capture_driver;

+

+extern int oocd_trace_register_commands(struct command_context_s *cmd_ctx);

+

+#endif /* OOCD_TRACE_TRACE_H */