Include assert.h in system.h to promote tree-wide use of assertions.
[fw/openocd] / src / jtag / jtag.c
index bbf90e042ac3613ab8b197864c0c7bfdb2dba169..3d43bc9e64899737c6dfbc81116990c139f08535 100644 (file)
@@ -5,6 +5,10 @@
  *   Copyright (C) 2007,2008 Ã˜yvind Harboe                                 *
  *   oyvind.harboe@zylin.com                                               *
  *                                                                         *
+ *   Copyright (C) 2009 SoftPLC Corporation                                *
+ *      http://softplc.com                                                    *
+ *   dick@softplc.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     *
 #include "config.h"
 #endif
 
-#include "replacements.h"
-
 #include "jtag.h"
 
-#include "command.h"
-#include "log.h"
+#ifdef HAVE_STRINGS_H
+#include <strings.h>
+#endif
+
+
+int jtag_flush_queue_count; /* count # of flushes for profiling / debugging purposes */
 
-#include "stdlib.h"
-#include "string.h"
-#include <unistd.h>
+static void jtag_add_scan_check(void (*jtag_add_scan)(int num_fields, scan_field_t *fields, tap_state_t state),
+               int num_fields, scan_field_t *fields, tap_state_t state);
 
 /* note that this is not marked as static as it must be available from outside jtag.c for those
    that implement the jtag_xxx() minidriver layer
 */
 int jtag_error=ERROR_OK;
 
-
 typedef struct cmd_queue_page_s
 {
        void *address;
@@ -51,52 +55,6 @@ typedef struct cmd_queue_page_s
 #define CMD_QUEUE_PAGE_SIZE (1024 * 1024)
 static cmd_queue_page_t *cmd_queue_pages = NULL;
 
-/* tap_move[i][j]: tap movement command to go from state i to state j
- * 0: Test-Logic-Reset
- * 1: Run-Test/Idle
- * 2: Shift-DR
- * 3: Pause-DR
- * 4: Shift-IR
- * 5: Pause-IR
- *
- * DRSHIFT->DRSHIFT and IRSHIFT->IRSHIFT have to be caught in interface specific code
- */
-u8 tap_move[6][6] =
-{
-/*       RESET  IDLE  DRSHIFT  DRPAUSE  IRSHIFT  IRPAUSE             */
-       {  0x7f, 0x00,    0x17,    0x0a,    0x1b,    0x16},     /* RESET */
-       {  0x7f, 0x00,    0x25,    0x05,    0x2b,    0x0b},     /* IDLE */
-       {  0x7f, 0x31,    0x00,    0x01,    0x0f,    0x2f},     /* DRSHIFT  */
-       {  0x7f, 0x30,    0x20,    0x17,    0x1e,    0x2f},     /* DRPAUSE  */
-       {  0x7f, 0x31,    0x07,    0x17,    0x00,    0x01},     /* IRSHIFT  */
-       {  0x7f, 0x30,    0x1c,    0x17,    0x20,    0x2f}      /* IRPAUSE  */
-};
-
-int tap_move_map[16] = {
-       0, -1, -1,  2, -1,  3, -1, -1,
-       1, -1, -1,  4, -1,  5, -1, -1
-};
-
-tap_transition_t tap_transitions[16] =
-{
-       {TAP_RESET,             TAP_IDLE},                      /* RESET */
-       {TAP_IRSELECT,  TAP_DRCAPTURE},         /* DRSELECT */
-       {TAP_DREXIT1,   TAP_DRSHIFT},           /* DRCAPTURE  */
-       {TAP_DREXIT1,   TAP_DRSHIFT},           /* DRSHIFT  */
-       {TAP_DRUPDATE,  TAP_DRPAUSE},           /* DREXIT1 */
-       {TAP_DREXIT2,   TAP_DRPAUSE},           /* DRPAUSE  */
-       {TAP_DRUPDATE,  TAP_DRSHIFT},           /* DREXIT2 */
-       {TAP_DRSELECT,  TAP_IDLE},                      /* DRUPDATE  */
-       {TAP_DRSELECT,  TAP_IDLE},                      /* IDLE */
-       {TAP_RESET,             TAP_IRCAPTURE},         /* IRSELECT */
-       {TAP_IREXIT1,   TAP_IRSHIFT},           /* IRCAPTURE  */
-       {TAP_IREXIT1,   TAP_IRSHIFT},           /* IRSHIFT  */
-       {TAP_IRUPDATE,  TAP_IRPAUSE},           /* IREXIT1 */
-       {TAP_IREXIT2,   TAP_IRPAUSE},           /* IRPAUSE  */
-       {TAP_IRUPDATE,  TAP_IRSHIFT},           /* IREXIT2 */
-       {TAP_DRSELECT,  TAP_IDLE}                       /* IRUPDATE  */
-};
-
 char* jtag_event_strings[] =
 {
        "JTAG controller reset (RESET or TRST)"
@@ -109,29 +67,40 @@ const Jim_Nvp nvp_jtag_tap_event[] = {
        { .name = NULL, .value = -1 }
 };
 
-/* kludge!!!! these are just global variables that the
- * interface use internally. They really belong
- * inside the drivers, but we don't want to break
- * linking the drivers!!!!
- */
-enum tap_state end_state = TAP_RESET;
-enum tap_state cur_state = TAP_RESET;
 int jtag_trst = 0;
 int jtag_srst = 0;
 
+#ifndef HAVE_JTAG_MINIDRIVER_H
+struct jtag_callback_entry
+{
+       struct jtag_callback_entry *next;
+
+       jtag_callback_t callback;
+       u8 *in;
+       jtag_callback_data_t data1;
+       jtag_callback_data_t data2;
+       jtag_callback_data_t data3;
+};
+
+
+static struct jtag_callback_entry *jtag_callback_queue_head = NULL;
+static struct jtag_callback_entry *jtag_callback_queue_tail = NULL;
+#endif
+
+
 jtag_command_t *jtag_command_queue = NULL;
 jtag_command_t **last_comand_pointer = &jtag_command_queue;
 static jtag_tap_t *jtag_all_taps = NULL;
 
 enum reset_types jtag_reset_config = RESET_NONE;
-enum tap_state cmd_queue_end_state = TAP_RESET;
-enum tap_state cmd_queue_cur_state = TAP_RESET;
+tap_state_t cmd_queue_end_state = TAP_RESET;
+tap_state_t cmd_queue_cur_state = TAP_RESET;
 
 int jtag_verify_capture_ir = 1;
 
 /* how long the OpenOCD should wait before attempting JTAG communication after reset lines deasserted (in ms) */
-int jtag_nsrst_delay = 0; /* default to no nSRST delay */
-int jtag_ntrst_delay = 0; /* default to no nTRST delay */
+static int jtag_nsrst_delay = 0; /* default to no nSRST delay */
+static int jtag_ntrst_delay = 0; /* default to no nTRST delay */
 
 /* maximum number of JTAG devices expected in the chain
  */
@@ -204,6 +173,10 @@ static int hasKHz = 0;
        extern jtag_interface_t rlink_interface;
 #endif
 
+#if BUILD_ARMJTAGEW == 1
+       extern jtag_interface_t armjtagew_interface;
+#endif
+
 jtag_interface_t *jtag_interfaces[] = {
 #if BUILD_ECOSBOARD == 1
        &zy1000_interface,
@@ -246,6 +219,9 @@ jtag_interface_t *jtag_interfaces[] = {
 #endif
 #if BUILD_RLINK == 1
        &rlink_interface,
+#endif
+#if BUILD_ARMJTAGEW == 1
+       &armjtagew_interface,
 #endif
        NULL,
 };
@@ -253,35 +229,36 @@ jtag_interface_t *jtag_interfaces[] = {
 jtag_interface_t *jtag = NULL;
 
 /* configuration */
-jtag_interface_t *jtag_interface = NULL;
+static jtag_interface_t *jtag_interface = NULL;
 int jtag_speed = 0;
 
 /* forward declarations */
-void jtag_add_pathmove(int num_states, enum tap_state *path);
-void jtag_add_runtest(int num_cycles, enum tap_state endstate);
-void jtag_add_end_state(enum tap_state endstate);
-void jtag_add_sleep(u32 us);
-int jtag_execute_queue(void);
-
+//void jtag_add_pathmove(int num_states, tap_state_t *path);
+//void jtag_add_runtest(int num_cycles, tap_state_t endstate);
+//void jtag_add_end_state(tap_state_t endstate);
+//void jtag_add_sleep(u32 us);
+//int jtag_execute_queue(void);
+static tap_state_t tap_state_by_name(const char *name);
 
 /* jtag commands */
-int handle_interface_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
-int handle_jtag_speed_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
-int handle_jtag_khz_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
-int handle_jtag_device_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
-int handle_reset_config_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
-int handle_jtag_nsrst_delay_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
-int handle_jtag_ntrst_delay_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
+static int handle_interface_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
+static int handle_jtag_speed_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
+static int handle_jtag_khz_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
+static int handle_jtag_device_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
+static int handle_reset_config_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
+static int handle_jtag_nsrst_delay_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
+static int handle_jtag_ntrst_delay_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
 
-int handle_scan_chain_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
+static int handle_scan_chain_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
 
-int handle_endstate_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
-int handle_jtag_reset_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
-int handle_runtest_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
-int handle_irscan_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
-int Jim_Command_drscan(Jim_Interp *interp, int argc, Jim_Obj *const *argv);
+static int handle_endstate_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
+static int handle_jtag_reset_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
+static int handle_runtest_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
+static int handle_irscan_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
+static int Jim_Command_drscan(Jim_Interp *interp, int argc, Jim_Obj *const *argv);
+static int Jim_Command_flush_count(Jim_Interp *interp, int argc, Jim_Obj *const *args);
 
-int handle_verify_ircapture_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
+static int handle_verify_ircapture_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
 
 jtag_tap_t *jtag_AllTaps(void)
 {
@@ -318,14 +295,13 @@ int jtag_NumEnabledTaps(void)
        return n;
 }
 
-
 jtag_tap_t *jtag_TapByString( const char *s )
 {
        jtag_tap_t *t;
        char *cp;
 
        t = jtag_AllTaps();
-       // try name first
+       /* try name first */
        while(t){
                if( 0 == strcmp( t->dotted_name, s ) ){
                        break;
@@ -333,7 +309,7 @@ jtag_tap_t *jtag_TapByString( const char *s )
                        t = t->next_tap;
                }
        }
-       // backup plan is by number
+       /* backup plan is by number */
        if( t == NULL ){
                /* ok - is "s" a number? */
                int n;
@@ -550,28 +526,50 @@ static void jtag_prelude1(void)
                jtag_call_event_callbacks(JTAG_TRST_ASSERTED);
 }
 
-static void jtag_prelude(enum tap_state state)
+static void jtag_prelude(tap_state_t state)
 {
        jtag_prelude1();
 
-       if (state != -1)
+       if (state != TAP_INVALID)
                jtag_add_end_state(state);
 
        cmd_queue_cur_state = cmd_queue_end_state;
 }
 
-void jtag_add_ir_scan(int num_fields, scan_field_t *fields, enum tap_state state)
+void jtag_add_ir_scan_noverify(int num_fields, scan_field_t *fields, tap_state_t state)
 {
        int retval;
-
        jtag_prelude(state);
 
        retval=interface_jtag_add_ir_scan(num_fields, fields, cmd_queue_end_state);
        if (retval!=ERROR_OK)
                jtag_error=retval;
+
+}
+
+
+void jtag_add_ir_scan(int num_fields, scan_field_t *fields, tap_state_t state)
+{
+       /* 8 x 32 bit id's is enough for all invoations */
+       int j;
+       for (j = 0; j < num_fields; j++)
+       {
+               fields[j].check_value=NULL;
+               fields[j].check_mask=NULL;
+               /* if we are to run a verification of the ir scan, we need to get the input back.
+                * We may have to allocate space if the caller didn't ask for the input back.
+                */
+               if (jtag_verify_capture_ir)
+               {
+                       fields[j].check_value=fields[j].tap->expected;
+                       fields[j].check_mask=fields[j].tap->expected_mask;
+               }
+       }
+
+       jtag_add_scan_check(jtag_add_ir_scan_noverify, num_fields, fields, state);
 }
 
-int MINIDRIVER(interface_jtag_add_ir_scan)(int num_fields, scan_field_t *fields, enum tap_state state)
+int MINIDRIVER(interface_jtag_add_ir_scan)(int num_fields, scan_field_t *fields, tap_state_t state)
 {
        jtag_command_t **last_cmd;
        jtag_tap_t *tap;
@@ -580,7 +578,6 @@ int MINIDRIVER(interface_jtag_add_ir_scan)(int num_fields, scan_field_t *fields,
        int nth_tap;
        int scan_size = 0;
 
-
        last_cmd = jtag_get_last_command_p();
 
        /* allocate memory for a new list member */
@@ -602,17 +599,19 @@ int MINIDRIVER(interface_jtag_add_ir_scan)(int num_fields, scan_field_t *fields,
        for(;;){
                int found = 0;
 
-               // do this here so it is not forgotten
+               /* do this here so it is not forgotten */
                tap = jtag_NextEnabledTap(tap);
                if( tap == NULL ){
                        break;
                }
                nth_tap++;
+
+               assert(nth_tap < x );
+
                scan_size = tap->ir_length;
                (*last_cmd)->cmd.scan->fields[nth_tap].tap = tap;
                (*last_cmd)->cmd.scan->fields[nth_tap].num_bits = scan_size;
-               (*last_cmd)->cmd.scan->fields[nth_tap].in_value = NULL;
-               (*last_cmd)->cmd.scan->fields[nth_tap].in_handler = NULL;       /* disable verification by default */
+               (*last_cmd)->cmd.scan->fields[nth_tap].in_value = NULL; /* do not collect input for tap's in bypass */
 
                /* search the list */
                for (j = 0; j < num_fields; j++)
@@ -620,22 +619,8 @@ int MINIDRIVER(interface_jtag_add_ir_scan)(int num_fields, scan_field_t *fields,
                        if (tap == fields[j].tap)
                        {
                                found = 1;
+                               (*last_cmd)->cmd.scan->fields[nth_tap].in_value = fields[j].in_value;
                                (*last_cmd)->cmd.scan->fields[nth_tap].out_value = buf_cpy(fields[j].out_value, cmd_queue_alloc(CEIL(scan_size, 8)), scan_size);
-                               (*last_cmd)->cmd.scan->fields[nth_tap].out_mask = buf_cpy(fields[j].out_mask, cmd_queue_alloc(CEIL(scan_size, 8)), scan_size);
-
-                               if (jtag_verify_capture_ir)
-                               {
-                                       if (fields[j].in_handler==NULL)
-                                       {
-                                               jtag_set_check_value((*last_cmd)->cmd.scan->fields+nth_tap, tap->expected, tap->expected_mask, NULL);
-                                       } else
-                                       {
-                                               (*last_cmd)->cmd.scan->fields[nth_tap].in_handler = fields[j].in_handler;
-                                               (*last_cmd)->cmd.scan->fields[nth_tap].in_handler_priv = fields[j].in_handler_priv;
-                                               (*last_cmd)->cmd.scan->fields[nth_tap].in_check_value = tap->expected;
-                                               (*last_cmd)->cmd.scan->fields[nth_tap].in_check_mask = tap->expected_mask;
-                                       }
-                               }
 
                                tap->bypass = 0;
                                break;
@@ -646,18 +631,18 @@ int MINIDRIVER(interface_jtag_add_ir_scan)(int num_fields, scan_field_t *fields,
                {
                        /* if a tap isn't listed, set it to BYPASS */
                        (*last_cmd)->cmd.scan->fields[nth_tap].out_value = buf_set_ones(cmd_queue_alloc(CEIL(scan_size, 8)), scan_size);
-                       (*last_cmd)->cmd.scan->fields[nth_tap].out_mask = NULL;
                        tap->bypass = 1;
                }
 
                /* update device information */
                buf_cpy((*last_cmd)->cmd.scan->fields[nth_tap].out_value, tap->cur_instr, scan_size);
        }
+       assert(nth_tap == (x-1));
 
        return ERROR_OK;
 }
 
-void jtag_add_plain_ir_scan(int num_fields, scan_field_t *fields, enum tap_state state)
+void jtag_add_plain_ir_scan(int num_fields, scan_field_t *fields, tap_state_t state)
 {
        int retval;
 
@@ -668,7 +653,7 @@ void jtag_add_plain_ir_scan(int num_fields, scan_field_t *fields, enum tap_state
                jtag_error=retval;
 }
 
-int MINIDRIVER(interface_jtag_add_plain_ir_scan)(int num_fields, scan_field_t *fields, enum tap_state state)
+int MINIDRIVER(interface_jtag_add_plain_ir_scan)(int num_fields, scan_field_t *fields, tap_state_t state)
 {
        int i;
        jtag_command_t **last_cmd;
@@ -694,17 +679,12 @@ int MINIDRIVER(interface_jtag_add_plain_ir_scan)(int num_fields, scan_field_t *f
                (*last_cmd)->cmd.scan->fields[i].tap = fields[i].tap;
                (*last_cmd)->cmd.scan->fields[i].num_bits = num_bits;
                (*last_cmd)->cmd.scan->fields[i].out_value = buf_cpy(fields[i].out_value, cmd_queue_alloc(num_bytes), num_bits);
-               (*last_cmd)->cmd.scan->fields[i].out_mask = buf_cpy(fields[i].out_mask, cmd_queue_alloc(num_bytes), num_bits);
                (*last_cmd)->cmd.scan->fields[i].in_value = fields[i].in_value;
-               (*last_cmd)->cmd.scan->fields[i].in_check_value = fields[i].in_check_value;
-               (*last_cmd)->cmd.scan->fields[i].in_check_mask = fields[i].in_check_mask;
-               (*last_cmd)->cmd.scan->fields[i].in_handler = NULL;
-               (*last_cmd)->cmd.scan->fields[i].in_handler_priv = NULL;
        }
        return ERROR_OK;
 }
 
-void jtag_add_dr_scan(int num_fields, scan_field_t *fields, enum tap_state state)
+void jtag_add_dr_scan(int num_fields, scan_field_t *fields, tap_state_t state)
 {
        int retval;
 
@@ -715,7 +695,70 @@ void jtag_add_dr_scan(int num_fields, scan_field_t *fields, enum tap_state state
                jtag_error=retval;
 }
 
-int MINIDRIVER(interface_jtag_add_dr_scan)(int num_fields, scan_field_t *fields, enum tap_state state)
+
+int jtag_check_value_inner(u8 *captured, u8 *in_check_value, u8 *in_check_mask, int num_bits);
+
+static int jtag_check_value_mask_callback(u8 *in, jtag_callback_data_t data1, jtag_callback_data_t data2, jtag_callback_data_t data3)
+{
+       return jtag_check_value_inner(in, (u8 *)data1, (u8 *)data2, (int)data3);
+}
+
+static void jtag_add_scan_check(void (*jtag_add_scan)(int num_fields, scan_field_t *fields, tap_state_t state),
+               int num_fields, scan_field_t *fields, tap_state_t state)
+{
+       for (int i=0; i<num_fields; i++)
+       {
+               fields[i].allocated=0;
+               fields[i].modified=0;
+               if ((fields[i].check_value!=NULL)&&(fields[i].in_value==NULL))
+               {
+                       fields[i].modified=1;
+                       /* we need storage space... */
+#ifdef HAVE_JTAG_MINIDRIVER_H
+                       if (fields[i].num_bits<=32)
+                       {
+                               /* This is enough space and we're executing this synchronously */
+                               fields[i].in_value=(u8 *)&fields[i].intmp;
+                       } else
+                       {
+                               fields[i].in_value=(u8 *)malloc(CEIL(fields[i].num_bits, 8));
+                               fields[i].allocated=1;
+                       }
+#else
+                       fields[i].in_value=(u8 *)cmd_queue_alloc(CEIL(fields[i].num_bits, 8));
+#endif
+               }
+       }
+
+       jtag_add_scan(num_fields, fields, state);
+
+       for (int i=0; i<num_fields; i++)
+       {
+               if ((fields[i].check_value!=NULL)&&(fields[i].in_value!=NULL))
+               {
+                       /* this is synchronous for a minidriver */
+                       jtag_add_callback4(jtag_check_value_mask_callback, fields[i].in_value, (jtag_callback_data_t)fields[i].check_value, (jtag_callback_data_t)fields[i].check_mask, (jtag_callback_data_t)fields[i].num_bits);
+               }
+               if (fields[i].allocated)
+               {
+                       free(fields[i].in_value);
+               }
+               if (fields[i].modified)
+               {
+                       fields[i].in_value=NULL;
+               }
+       }
+}
+
+void jtag_add_dr_scan_check(int num_fields, scan_field_t *fields, tap_state_t state)
+{
+       jtag_add_scan_check(jtag_add_dr_scan, num_fields, fields, state);
+}
+
+
+
+
+int MINIDRIVER(interface_jtag_add_dr_scan)(int num_fields, scan_field_t *fields, tap_state_t state)
 {
        int j;
        int nth_tap;
@@ -771,12 +814,8 @@ int MINIDRIVER(interface_jtag_add_dr_scan)(int num_fields, scan_field_t *fields,
                                scan_size = fields[j].num_bits;
                                (*last_cmd)->cmd.scan->fields[field_count].num_bits = scan_size;
                                (*last_cmd)->cmd.scan->fields[field_count].out_value = buf_cpy(fields[j].out_value, cmd_queue_alloc(CEIL(scan_size, 8)), scan_size);
-                               (*last_cmd)->cmd.scan->fields[field_count].out_mask = buf_cpy(fields[j].out_mask, cmd_queue_alloc(CEIL(scan_size, 8)), scan_size);
                                (*last_cmd)->cmd.scan->fields[field_count].in_value = fields[j].in_value;
-                               (*last_cmd)->cmd.scan->fields[field_count].in_check_value = fields[j].in_check_value;
-                               (*last_cmd)->cmd.scan->fields[field_count].in_check_mask = fields[j].in_check_mask;
-                               (*last_cmd)->cmd.scan->fields[field_count].in_handler = fields[j].in_handler;
-                               (*last_cmd)->cmd.scan->fields[field_count++].in_handler_priv = fields[j].in_handler_priv;
+                               field_count++;
                        }
                }
                if (!found)
@@ -792,12 +831,8 @@ int MINIDRIVER(interface_jtag_add_dr_scan)(int num_fields, scan_field_t *fields,
                        /* program the scan field to 1 bit length, and ignore it's value */
                        (*last_cmd)->cmd.scan->fields[field_count].num_bits = 1;
                        (*last_cmd)->cmd.scan->fields[field_count].out_value = NULL;
-                       (*last_cmd)->cmd.scan->fields[field_count].out_mask = NULL;
                        (*last_cmd)->cmd.scan->fields[field_count].in_value = NULL;
-                       (*last_cmd)->cmd.scan->fields[field_count].in_check_value = NULL;
-                       (*last_cmd)->cmd.scan->fields[field_count].in_check_mask = NULL;
-                       (*last_cmd)->cmd.scan->fields[field_count].in_handler = NULL;
-                       (*last_cmd)->cmd.scan->fields[field_count++].in_handler_priv = NULL;
+                       field_count++;
                }
                else
                {
@@ -818,7 +853,7 @@ void MINIDRIVER(interface_jtag_add_dr_out)(jtag_tap_t *target_tap,
                int num_fields,
                const int *num_bits,
                const u32 *value,
-               enum tap_state end_state)
+               tap_state_t end_state)
 {
        int nth_tap;
        int field_count = 0;
@@ -882,12 +917,8 @@ void MINIDRIVER(interface_jtag_add_dr_out)(jtag_tap_t *target_tap,
                                buf_set_u32(out_value, 0, scan_size, value[j]);
                                (*last_cmd)->cmd.scan->fields[field_count].num_bits = scan_size;
                                (*last_cmd)->cmd.scan->fields[field_count].out_value = buf_cpy(out_value, cmd_queue_alloc(CEIL(scan_size, 8)), scan_size);
-                               (*last_cmd)->cmd.scan->fields[field_count].out_mask = NULL;
                                (*last_cmd)->cmd.scan->fields[field_count].in_value = NULL;
-                               (*last_cmd)->cmd.scan->fields[field_count].in_check_value = NULL;
-                               (*last_cmd)->cmd.scan->fields[field_count].in_check_mask = NULL;
-                               (*last_cmd)->cmd.scan->fields[field_count].in_handler = NULL;
-                               (*last_cmd)->cmd.scan->fields[field_count++].in_handler_priv = NULL;
+                               field_count++;
                        }
                } else
                {
@@ -902,17 +933,13 @@ void MINIDRIVER(interface_jtag_add_dr_out)(jtag_tap_t *target_tap,
                        /* program the scan field to 1 bit length, and ignore it's value */
                        (*last_cmd)->cmd.scan->fields[field_count].num_bits = 1;
                        (*last_cmd)->cmd.scan->fields[field_count].out_value = NULL;
-                       (*last_cmd)->cmd.scan->fields[field_count].out_mask = NULL;
                        (*last_cmd)->cmd.scan->fields[field_count].in_value = NULL;
-                       (*last_cmd)->cmd.scan->fields[field_count].in_check_value = NULL;
-                       (*last_cmd)->cmd.scan->fields[field_count].in_check_mask = NULL;
-                       (*last_cmd)->cmd.scan->fields[field_count].in_handler = NULL;
-                       (*last_cmd)->cmd.scan->fields[field_count++].in_handler_priv = NULL;
+                       field_count++;
                }
        }
 }
 
-void jtag_add_plain_dr_scan(int num_fields, scan_field_t *fields, enum tap_state state)
+void jtag_add_plain_dr_scan(int num_fields, scan_field_t *fields, tap_state_t state)
 {
        int retval;
 
@@ -923,7 +950,7 @@ void jtag_add_plain_dr_scan(int num_fields, scan_field_t *fields, enum tap_state
                jtag_error=retval;
 }
 
-int MINIDRIVER(interface_jtag_add_plain_dr_scan)(int num_fields, scan_field_t *fields, enum tap_state state)
+int MINIDRIVER(interface_jtag_add_plain_dr_scan)(int num_fields, scan_field_t *fields, tap_state_t state)
 {
        int i;
        jtag_command_t **last_cmd = jtag_get_last_command_p();
@@ -948,12 +975,7 @@ int MINIDRIVER(interface_jtag_add_plain_dr_scan)(int num_fields, scan_field_t *f
                (*last_cmd)->cmd.scan->fields[i].tap = fields[i].tap;
                (*last_cmd)->cmd.scan->fields[i].num_bits = num_bits;
                (*last_cmd)->cmd.scan->fields[i].out_value = buf_cpy(fields[i].out_value, cmd_queue_alloc(num_bytes), num_bits);
-               (*last_cmd)->cmd.scan->fields[i].out_mask = buf_cpy(fields[i].out_mask, cmd_queue_alloc(num_bytes), num_bits);
                (*last_cmd)->cmd.scan->fields[i].in_value = fields[i].in_value;
-               (*last_cmd)->cmd.scan->fields[i].in_check_value = fields[i].in_check_value;
-               (*last_cmd)->cmd.scan->fields[i].in_check_mask = fields[i].in_check_mask;
-               (*last_cmd)->cmd.scan->fields[i].in_handler = fields[i].in_handler;
-               (*last_cmd)->cmd.scan->fields[i].in_handler_priv = fields[i].in_handler_priv;
        }
 
        return ERROR_OK;
@@ -971,7 +993,7 @@ void jtag_add_tlr(void)
 
 int MINIDRIVER(interface_jtag_add_tlr)(void)
 {
-       enum tap_state state = TAP_RESET;
+       tap_state_t state = TAP_RESET;
        jtag_command_t **last_cmd = jtag_get_last_command_p();
 
        /* allocate memory for a new list member */
@@ -986,14 +1008,14 @@ int MINIDRIVER(interface_jtag_add_tlr)(void)
        return ERROR_OK;
 }
 
-void jtag_add_pathmove(int num_states, enum tap_state *path)
+void jtag_add_pathmove(int num_states, tap_state_t *path)
 {
-       enum tap_state cur_state=cmd_queue_cur_state;
+       tap_state_t cur_state = cmd_queue_cur_state;
        int i;
        int retval;
 
        /* the last state has to be a stable state */
-       if (tap_move_map[path[num_states - 1]] == -1)
+       if (!tap_is_state_stable(path[num_states - 1]))
        {
                LOG_ERROR("BUG: TAP path doesn't finish in a stable state");
                exit(-1);
@@ -1006,10 +1028,11 @@ void jtag_add_pathmove(int num_states, enum tap_state *path)
                        LOG_ERROR("BUG: TAP_RESET is not a valid state for pathmove sequences");
                        exit(-1);
                }
-               if ((tap_transitions[cur_state].low != path[i])&&
-                               (tap_transitions[cur_state].high != path[i]))
+
+               if ( tap_state_transition(cur_state, true)  != path[i]
+                 && tap_state_transition(cur_state, false) != path[i])
                {
-                       LOG_ERROR("BUG: %s -> %s isn't a valid TAP transition", jtag_state_name(cur_state), jtag_state_name(path[i]));
+                       LOG_ERROR("BUG: %s -> %s isn't a valid TAP transition", tap_state_name(cur_state), tap_state_name(path[i]));
                        exit(-1);
                }
                cur_state = path[i];
@@ -1017,13 +1040,13 @@ void jtag_add_pathmove(int num_states, enum tap_state *path)
 
        jtag_prelude1();
 
-       retval=interface_jtag_add_pathmove(num_states, path);
+       retval = interface_jtag_add_pathmove(num_states, path);
        cmd_queue_cur_state = path[num_states - 1];
        if (retval!=ERROR_OK)
                jtag_error=retval;
 }
 
-int MINIDRIVER(interface_jtag_add_pathmove)(int num_states, enum tap_state *path)
+int MINIDRIVER(interface_jtag_add_pathmove)(int num_states, tap_state_t *path)
 {
        jtag_command_t **last_cmd = jtag_get_last_command_p();
        int i;
@@ -1036,7 +1059,7 @@ int MINIDRIVER(interface_jtag_add_pathmove)(int num_states, enum tap_state *path
 
        (*last_cmd)->cmd.pathmove = cmd_queue_alloc(sizeof(pathmove_command_t));
        (*last_cmd)->cmd.pathmove->num_states = num_states;
-       (*last_cmd)->cmd.pathmove->path = cmd_queue_alloc(sizeof(enum tap_state) * num_states);
+       (*last_cmd)->cmd.pathmove->path = cmd_queue_alloc(sizeof(tap_state_t) * num_states);
 
        for (i = 0; i < num_states; i++)
                (*last_cmd)->cmd.pathmove->path[i] = path[i];
@@ -1044,7 +1067,7 @@ int MINIDRIVER(interface_jtag_add_pathmove)(int num_states, enum tap_state *path
        return ERROR_OK;
 }
 
-int MINIDRIVER(interface_jtag_add_runtest)(int num_cycles, enum tap_state state)
+int MINIDRIVER(interface_jtag_add_runtest)(int num_cycles, tap_state_t state)
 {
        jtag_command_t **last_cmd = jtag_get_last_command_p();
 
@@ -1061,7 +1084,7 @@ int MINIDRIVER(interface_jtag_add_runtest)(int num_cycles, enum tap_state state)
        return ERROR_OK;
 }
 
-void jtag_add_runtest(int num_cycles, enum tap_state state)
+void jtag_add_runtest(int num_cycles, tap_state_t state)
 {
        int retval;
 
@@ -1093,11 +1116,22 @@ void jtag_add_clocks( int num_cycles )
 {
        int retval;
 
-       jtag_prelude1();
+       if( !tap_is_state_stable(cmd_queue_cur_state) )
+       {
+                LOG_ERROR( "jtag_add_clocks() was called with TAP in non-stable state \"%s\"",
+                                tap_state_name(cmd_queue_cur_state) );
+                jtag_error = ERROR_JTAG_NOT_STABLE_STATE;
+                return;
+       }
 
-       retval=interface_jtag_add_clocks(num_cycles);
-       if (retval!=ERROR_OK)
-               jtag_error=retval;
+       if( num_cycles > 0 )
+       {
+               jtag_prelude1();
+
+               retval = interface_jtag_add_clocks(num_cycles);
+               if (retval != ERROR_OK)
+                       jtag_error=retval;
+       }
 }
 
 void jtag_add_reset(int req_tlr_or_trst, int req_srst)
@@ -1220,7 +1254,7 @@ int MINIDRIVER(interface_jtag_add_reset)(int req_trst, int req_srst)
        return ERROR_OK;
 }
 
-void jtag_add_end_state(enum tap_state state)
+void jtag_add_end_state(tap_state_t state)
 {
        cmd_queue_end_state = state;
        if ((cmd_queue_end_state == TAP_DRSHIFT)||(cmd_queue_end_state == TAP_IRSHIFT))
@@ -1279,7 +1313,7 @@ int jtag_build_buffer(scan_command_t *cmd, u8 **buffer)
        bit_count = 0;
 
 #ifdef _DEBUG_JTAG_IO_
-       LOG_DEBUG("num_fields: %i",cmd->num_fields);
+       LOG_DEBUG("%s num_fields: %i", cmd->ir_scan ? "IRSCAN" : "DRSCAN", cmd->num_fields);
 #endif
 
        for (i = 0; i < cmd->num_fields; i++)
@@ -1287,7 +1321,7 @@ int jtag_build_buffer(scan_command_t *cmd, u8 **buffer)
                if (cmd->fields[i].out_value)
                {
 #ifdef _DEBUG_JTAG_IO_
-                       char* char_buf = buf_to_str(cmd->fields[i].out_value, (cmd->fields[i].num_bits > 64) ? 64 : cmd->fields[i].num_bits, 16);
+                       char* char_buf = buf_to_str(cmd->fields[i].out_value, (cmd->fields[i].num_bits > DEBUG_JTAG_IOZ) ? DEBUG_JTAG_IOZ : cmd->fields[i].num_bits, 16);
 #endif
                        buf_set_buf(cmd->fields[i].out_value, 0, *buffer, bit_count, cmd->fields[i].num_bits);
 #ifdef _DEBUG_JTAG_IO_
@@ -1295,12 +1329,19 @@ int jtag_build_buffer(scan_command_t *cmd, u8 **buffer)
                        free(char_buf);
 #endif
                }
+               else
+               {
+#ifdef _DEBUG_JTAG_IO_
+                       LOG_DEBUG("fields[%i].out_value[%i]: NULL", i, cmd->fields[i].num_bits);
+#endif
+               }
 
                bit_count += cmd->fields[i].num_bits;
+       }
+
 #ifdef _DEBUG_JTAG_IO_
-               LOG_DEBUG("bit_count totalling: %i",  bit_count );
+       //LOG_DEBUG("bit_count totalling: %i",  bit_count );
 #endif
-       }
 
        return bit_count;
 }
@@ -1319,13 +1360,13 @@ int jtag_read_buffer(u8 *buffer, scan_command_t *cmd)
                /* if neither in_value nor in_handler
                 * are specified we don't have to examine this field
                 */
-               if (cmd->fields[i].in_value || cmd->fields[i].in_handler)
+               if (cmd->fields[i].in_value)
                {
                        int num_bits = cmd->fields[i].num_bits;
                        u8 *captured = buf_set_buf(buffer, bit_count, malloc(CEIL(num_bits, 8)), 0, num_bits);
 
 #ifdef _DEBUG_JTAG_IO_
-                       char *char_buf = buf_to_str(captured, (num_bits > 64) ? 64 : num_bits, 16);
+                       char *char_buf = buf_to_str(captured, (num_bits > DEBUG_JTAG_IOZ) ? DEBUG_JTAG_IOZ : num_bits, 16);
                        LOG_DEBUG("fields[%i].in_value[%i]: 0x%s", i, num_bits, char_buf);
                        free(char_buf);
 #endif
@@ -1333,28 +1374,6 @@ int jtag_read_buffer(u8 *buffer, scan_command_t *cmd)
                        if (cmd->fields[i].in_value)
                        {
                                buf_cpy(captured, cmd->fields[i].in_value, num_bits);
-
-                               if (cmd->fields[i].in_handler)
-                               {
-                                       if (cmd->fields[i].in_handler(cmd->fields[i].in_value, cmd->fields[i].in_handler_priv, cmd->fields+i) != ERROR_OK)
-                                       {
-                                               LOG_WARNING("in_handler: with \"in_value\", mismatch in %s", cmd->ir_scan ? "SIR" : "SDR" );
-                                               retval = ERROR_JTAG_QUEUE_FAILED;
-                                       }
-                               }
-                       }
-
-                       /* no in_value specified, but a handler takes care of the scanned data */
-                       if (cmd->fields[i].in_handler && (!cmd->fields[i].in_value))
-                       {
-                               if (cmd->fields[i].in_handler(captured, cmd->fields[i].in_handler_priv, cmd->fields+i) != ERROR_OK)
-                               {
-                                       /* We're going to call the error:handler later, but if the in_handler
-                                        * reported an error we report this failure upstream
-                                        */
-                                       LOG_WARNING("in_handler: w/o \"in_value\", mismatch in %s",  cmd->ir_scan ? "SIR" : "SDR" );
-                                       retval = ERROR_JTAG_QUEUE_FAILED;
-                               }
                        }
 
                        free(captured);
@@ -1370,34 +1389,35 @@ static const char *jtag_tap_name(jtag_tap_t *tap)
        return (tap == NULL) ? "(unknown)" : tap->dotted_name;
 }
 
-int jtag_check_value(u8 *captured, void *priv, scan_field_t *field)
+int jtag_check_value_inner(u8 *captured, u8 *in_check_value, u8 *in_check_mask, int num_bits)
 {
        int retval = ERROR_OK;
-       int num_bits = field->num_bits;
 
        int compare_failed = 0;
 
-       if (field->in_check_mask)
-               compare_failed = buf_cmp_mask(captured, field->in_check_value, field->in_check_mask, num_bits);
+       if (in_check_mask)
+               compare_failed = buf_cmp_mask(captured, in_check_value, in_check_mask, num_bits);
        else
-               compare_failed = buf_cmp(captured, field->in_check_value, num_bits);
+               compare_failed = buf_cmp(captured, in_check_value, num_bits);
 
        if (compare_failed){
                /* An error handler could have caught the failing check
                 * only report a problem when there wasn't a handler, or if the handler
                 * acknowledged the error
                 */
+               /*
                LOG_WARNING("TAP %s:",
                                        jtag_tap_name(field->tap));
+                                       */
                if (compare_failed)
                {
-                       char *captured_char = buf_to_str(captured, (num_bits > 64) ? 64 : num_bits, 16);
-                       char *in_check_value_char = buf_to_str(field->in_check_value, (num_bits > 64) ? 64 : num_bits, 16);
+                       char *captured_char = buf_to_str(captured, (num_bits > DEBUG_JTAG_IOZ) ? DEBUG_JTAG_IOZ : num_bits, 16);
+                       char *in_check_value_char = buf_to_str(in_check_value, (num_bits > DEBUG_JTAG_IOZ) ? DEBUG_JTAG_IOZ : num_bits, 16);
 
-                       if (field->in_check_mask)
+                       if (in_check_mask)
                        {
                                char *in_check_mask_char;
-                               in_check_mask_char = buf_to_str(field->in_check_mask, (num_bits > 64) ? 64 : num_bits, 16);
+                               in_check_mask_char = buf_to_str(in_check_mask, (num_bits > DEBUG_JTAG_IOZ) ? DEBUG_JTAG_IOZ : num_bits, 16);
                                LOG_WARNING("value captured during scan didn't pass the requested check:");
                                LOG_WARNING("captured: 0x%s check_value: 0x%s check_mask: 0x%s",
                                                        captured_char, in_check_value_char, in_check_mask_char);
@@ -1418,21 +1438,24 @@ int jtag_check_value(u8 *captured, void *priv, scan_field_t *field)
        return retval;
 }
 
-/*
-  set up checking of this field using the in_handler. The values passed in must be valid until
-  after jtag_execute() has completed.
- */
-void jtag_set_check_value(scan_field_t *field, u8 *value, u8 *mask, error_handler_t *in_error_handler)
+void jtag_check_value_mask(scan_field_t *field, u8 *value, u8 *mask)
 {
-       if (value)
-               field->in_handler = jtag_check_value;
-       else
-               field->in_handler = NULL;       /* No check, e.g. embeddedice uses value==NULL to indicate no check */
-       field->in_handler_priv = NULL;
-       field->in_check_value = value;
-       field->in_check_mask = mask;
+       assert(field->in_value != NULL);
+
+       if (value==NULL)
+       {
+               /* no checking to do */
+               return;
+       }
+
+       jtag_execute_queue_noclear();
+
+       int retval=jtag_check_value_inner(field->in_value, value, mask, field->num_bits);
+       jtag_set_error(retval);
 }
 
+
+
 enum scan_type jtag_scan_type(scan_command_t *cmd)
 {
        int i;
@@ -1440,7 +1463,7 @@ enum scan_type jtag_scan_type(scan_command_t *cmd)
 
        for (i = 0; i < cmd->num_fields; i++)
        {
-               if (cmd->fields[i].in_value || cmd->fields[i].in_handler)
+               if (cmd->fields[i].in_value)
                        type |= SCAN_IN;
                if (cmd->fields[i].out_value)
                        type |= SCAN_OUT;
@@ -1449,7 +1472,47 @@ enum scan_type jtag_scan_type(scan_command_t *cmd)
        return type;
 }
 
-int MINIDRIVER(interface_jtag_execute_queue)(void)
+
+#ifndef HAVE_JTAG_MINIDRIVER_H
+/* add callback to end of queue */
+void jtag_add_callback4(jtag_callback_t callback, u8 *in, jtag_callback_data_t data1, jtag_callback_data_t data2, jtag_callback_data_t data3)
+{
+       struct jtag_callback_entry *entry=cmd_queue_alloc(sizeof(struct jtag_callback_entry));
+
+       entry->next=NULL;
+       entry->callback=callback;
+       entry->in=in;
+       entry->data1=data1;
+       entry->data2=data2;
+       entry->data3=data3;
+
+       if (jtag_callback_queue_head==NULL)
+       {
+               jtag_callback_queue_head=entry;
+               jtag_callback_queue_tail=entry;
+       } else
+       {
+               jtag_callback_queue_tail->next=entry;
+               jtag_callback_queue_tail=entry;
+       }
+}
+
+
+static int jtag_convert_to_callback4(u8 *in, jtag_callback_data_t data1, jtag_callback_data_t data2, jtag_callback_data_t data3)
+{
+       ((jtag_callback1_t)data1)(in);
+       return ERROR_OK;
+}
+
+void jtag_add_callback(jtag_callback1_t callback, u8 *in)
+{
+       jtag_add_callback4(jtag_convert_to_callback4, in, (jtag_callback_data_t)callback, 0, 0);
+}
+#endif
+
+#ifndef HAVE_JTAG_MINIDRIVER_H
+
+int interface_jtag_execute_queue(void)
 {
        int retval;
 
@@ -1461,21 +1524,49 @@ int MINIDRIVER(interface_jtag_execute_queue)(void)
 
        retval = jtag->execute_queue();
 
+       if (retval == ERROR_OK)
+       {
+               struct jtag_callback_entry *entry;
+               for (entry=jtag_callback_queue_head; entry!=NULL; entry=entry->next)
+               {
+                       retval=entry->callback(entry->in, entry->data1, entry->data2, entry->data3);
+                       if (retval!=ERROR_OK)
+                               break;
+               }
+       }
+
        cmd_queue_free();
 
+       jtag_callback_queue_head = NULL;
+       jtag_callback_queue_tail = NULL;
+
        jtag_command_queue = NULL;
        last_comand_pointer = &jtag_command_queue;
 
        return retval;
 }
+#endif
 
-int jtag_execute_queue(void)
+void jtag_execute_queue_noclear(void)
 {
+       /* each flush can take as much as 1-2ms on high bandwidth low latency interfaces.
+        * E.g. a JTAG over TCP/IP or USB....
+        */
+       jtag_flush_queue_count++;
+
        int retval=interface_jtag_execute_queue();
-       if (retval==ERROR_OK)
+       /* we keep the first error */
+       if ((jtag_error==ERROR_OK)&&(retval!=ERROR_OK))
        {
-               retval=jtag_error;
+               jtag_error=retval;
        }
+}
+
+int jtag_execute_queue(void)
+{
+       int retval;
+       jtag_execute_queue_noclear();
+       retval=jtag_error;
        jtag_error=ERROR_OK;
        return retval;
 }
@@ -1516,12 +1607,11 @@ int jtag_examine_chain(void)
        field.tap = NULL;
        field.num_bits = sizeof(idcode_buffer) * 8;
        field.out_value = idcode_buffer;
-       field.out_mask = NULL;
+
        field.in_value = idcode_buffer;
-       field.in_check_value = NULL;
-       field.in_check_mask = NULL;
-       field.in_handler = NULL;
-       field.in_handler_priv = NULL;
+
+
+
 
        for (i = 0; i < JTAG_MAX_CHAIN_SIZE; i++)
        {
@@ -1544,7 +1634,7 @@ int jtag_examine_chain(void)
                return ERROR_JTAG_INIT_FAILED;
        }
 
-       // point at the 1st tap
+       /* point at the 1st tap */
        tap = jtag_NextEnabledTap(NULL);
        if( tap == NULL ){
                LOG_ERROR("JTAG: No taps enabled?");
@@ -1568,7 +1658,9 @@ int jtag_examine_chain(void)
                        u32 part;
                        u32 version;
 
-                       if (idcode == 0x000000FF)
+                       /* some devices, such as AVR will output all 1's instead of TDI
+                       input value at end of chain. */
+                       if ((idcode == 0x000000FF)||(idcode == 0xFFFFFFFF))
                        {
                                int unexpected=0;
                                /* End of chain (invalid manufacturer ID)
@@ -1585,7 +1677,7 @@ int jtag_examine_chain(void)
                                for (bit_count += 32; bit_count < (JTAG_MAX_CHAIN_SIZE * 32) - 31;bit_count += 32)
                                {
                                        idcode = buf_get_u32(idcode_buffer, bit_count, 32);
-                                       if (unexpected||(idcode != 0x000000FF))
+                                       if (unexpected||((idcode != 0x000000FF)&&(idcode != 0xFFFFFFFF)))
                                        {
                                                LOG_WARNING("Unexpected idcode after end of chain! %d 0x%08x", bit_count, idcode);
                                                unexpected = 1;
@@ -1692,12 +1784,8 @@ int jtag_validate_chain(void)
        field.tap = NULL;
        field.num_bits = total_ir_length;
        field.out_value = ir_test;
-       field.out_mask = NULL;
        field.in_value = ir_test;
-       field.in_check_value = NULL;
-       field.in_check_mask = NULL;
-       field.in_handler = NULL;
-       field.in_handler_priv = NULL;
+
 
        jtag_add_plain_ir_scan(1, &field, TAP_RESET);
        jtag_execute_queue();
@@ -1748,9 +1836,7 @@ static Jim_Nvp nvp_config_opts[] = {
        { .name = NULL,          .value = -1 }
 };
 
-static int
-jtag_tap_configure_cmd( Jim_GetOptInfo *goi,
-               jtag_tap_t * tap)
+static int jtag_tap_configure_cmd( Jim_GetOptInfo *goi, jtag_tap_t * tap)
 {
        Jim_Nvp *n;
        Jim_Obj *o;
@@ -1797,7 +1883,7 @@ jtag_tap_configure_cmd( Jim_GetOptInfo *goi,
                                        jteap = tap->event_action;
                                        /* replace existing? */
                                        while (jteap) {
-                                               if (jteap->event == n->value) {
+                                               if (jteap->event == (enum jtag_tap_event)n->value) {
                                                        break;
                                                }
                                                jteap = jteap->next;
@@ -2202,6 +2288,7 @@ int jtag_register_commands(struct command_context_s *cmd_ctx)
        register_command(cmd_ctx, NULL, "irscan", handle_irscan_command,
                COMMAND_EXEC, "execute IR scan <device> <instr> [dev2] [instr2] ...");
        register_jim(cmd_ctx, "drscan", Jim_Command_drscan, "execute DR scan <device> <num_bits> <value> <num_bits1> <value2> ...");
+       register_jim(cmd_ctx, "flush_count", Jim_Command_flush_count, "returns number of times the JTAG queue has been flushed");
 
        register_command(cmd_ctx, NULL, "verify_ircapture", handle_verify_ircapture_command,
                COMMAND_ANY, "verify value captured during Capture-IR <enable|disable>");
@@ -2344,7 +2431,7 @@ static int default_srst_asserted(int *srst_asserted)
        return ERROR_OK;
 }
 
-int handle_interface_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
+static int handle_interface_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
 {
        int i;
        int retval;
@@ -2407,7 +2494,7 @@ int handle_interface_command(struct command_context_s *cmd_ctx, char *cmd, char
        return ERROR_JTAG_INVALID_INTERFACE;
 }
 
-int handle_jtag_device_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
+static int handle_jtag_device_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
 {
        int e;
        char buf[1024];
@@ -2430,9 +2517,9 @@ int handle_jtag_device_command(struct command_context_s *cmd_ctx, char *cmd, cha
                                   args[0],
                                   args[1],
                                   args[2] );
-       command_print( cmd_ctx, "Example: STM32 has 2 taps, the cortexM3(len4) + boundryscan(len5)");
-       command_print( cmd_ctx, "jtag newtap stm32 cortexm3  ....., thus creating the tap: \"stm32.cortexm3\"");
-       command_print( cmd_ctx, "jtag newtap stm32 boundry  ....., and the tap: \"stm32.boundery\"");
+       command_print( cmd_ctx, "Example: STM32 has 2 taps, the cortexM3(len4) + boundaryscan(len5)");
+       command_print( cmd_ctx, "jtag newtap stm32 cortexm3 ....., thus creating the tap: \"stm32.cortexm3\"");
+       command_print( cmd_ctx, "jtag newtap stm32 boundary ....., and the tap: \"stm32.boundary\"");
        command_print( cmd_ctx, "And then refer to the taps by the dotted name.");
 
        newargs[0] = Jim_NewStringObj( interp, "jtag", -1   );
@@ -2468,7 +2555,7 @@ int handle_jtag_device_command(struct command_context_s *cmd_ctx, char *cmd, cha
        return e;
 }
 
-int handle_scan_chain_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
+static int handle_scan_chain_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
 {
        jtag_tap_t *tap;
 
@@ -2505,7 +2592,7 @@ int handle_scan_chain_command(struct command_context_s *cmd_ctx, char *cmd, char
        return ERROR_OK;
 }
 
-int handle_reset_config_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
+static int handle_reset_config_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
 {
        if (argc < 1)
                return ERROR_COMMAND_SYNTAX_ERROR;
@@ -2581,7 +2668,7 @@ int handle_reset_config_command(struct command_context_s *cmd_ctx, char *cmd, ch
        return ERROR_OK;
 }
 
-int handle_jtag_nsrst_delay_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
+static int handle_jtag_nsrst_delay_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
 {
        if (argc < 1)
        {
@@ -2596,7 +2683,7 @@ int handle_jtag_nsrst_delay_command(struct command_context_s *cmd_ctx, char *cmd
        return ERROR_OK;
 }
 
-int handle_jtag_ntrst_delay_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
+static int handle_jtag_ntrst_delay_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
 {
        if (argc < 1)
        {
@@ -2611,7 +2698,7 @@ int handle_jtag_ntrst_delay_command(struct command_context_s *cmd_ctx, char *cmd
        return ERROR_OK;
 }
 
-int handle_jtag_speed_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
+static int handle_jtag_speed_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
 {
        int retval=ERROR_OK;
 
@@ -2639,7 +2726,7 @@ int handle_jtag_speed_command(struct command_context_s *cmd_ctx, char *cmd, char
        return retval;
 }
 
-int handle_jtag_khz_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
+static int handle_jtag_khz_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
 {
        int retval=ERROR_OK;
        LOG_DEBUG("handle jtag khz");
@@ -2689,9 +2776,9 @@ int handle_jtag_khz_command(struct command_context_s *cmd_ctx, char *cmd, char *
 
 }
 
-int handle_endstate_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
+static int handle_endstate_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
 {
-       enum tap_state state;
+       tap_state_t state;
 
        if (argc < 1)
        {
@@ -2699,21 +2786,20 @@ int handle_endstate_command(struct command_context_s *cmd_ctx, char *cmd, char *
        }
        else
        {
-               for (state = 0; state < 16; state++)
-               {
-                       if (strcmp(args[0], jtag_state_name(state)) == 0)
-                       {
-                               jtag_add_end_state(state);
-                               jtag_execute_queue();
-                       }
+               state = tap_state_by_name( args[0] );
+               if( state < 0 ){
+                       command_print( cmd_ctx, "Invalid state name: %s\n", args[0] );
+                       return ERROR_COMMAND_SYNTAX_ERROR;
                }
+               jtag_add_end_state(state);
+               jtag_execute_queue();
        }
-       command_print(cmd_ctx, "current endstate: %s", jtag_state_name(cmd_queue_end_state));
+       command_print(cmd_ctx, "current endstate: %s", tap_state_name(cmd_queue_end_state));
 
        return ERROR_OK;
 }
 
-int handle_jtag_reset_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
+static int handle_jtag_reset_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
 {
        int trst = -1;
        int srst = -1;
@@ -2750,31 +2836,59 @@ int handle_jtag_reset_command(struct command_context_s *cmd_ctx, char *cmd, char
        return ERROR_OK;
 }
 
-int handle_runtest_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
+static int handle_runtest_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
 {
        if (argc < 1)
        {
                return ERROR_COMMAND_SYNTAX_ERROR;
        }
 
-       jtag_add_runtest(strtol(args[0], NULL, 0), -1);
+       jtag_add_runtest(strtol(args[0], NULL, 0), TAP_INVALID);
        jtag_execute_queue();
 
        return ERROR_OK;
 
 }
 
-int handle_irscan_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
+static int handle_irscan_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
 {
        int i;
        scan_field_t *fields;
        jtag_tap_t *tap;
+       tap_state_t endstate;
 
        if ((argc < 2) || (argc % 2))
        {
                return ERROR_COMMAND_SYNTAX_ERROR;
        }
 
+       /* optional "-endstate" */
+       /*          "statename" */
+       /* at the end of the arguments. */
+       /* assume none. */
+       endstate = TAP_INVALID;
+       if( argc >= 4 ){
+               /* have at least one pair of numbers. */
+               /* is last pair the magic text? */
+               if( 0 == strcmp( "-endstate", args[ argc - 2 ] ) ){
+                       const char *cpA;
+                       const char *cpS;
+                       cpA = args[ argc-1 ];
+                       for( endstate = 0 ; endstate < TAP_NUM_STATES ; endstate++ ){
+                               cpS = tap_state_name( endstate );
+                               if( 0 == strcmp( cpA, cpS ) ){
+                                       break;
+                               }
+                       }
+                       if( endstate >= TAP_NUM_STATES ){
+                               return ERROR_COMMAND_SYNTAX_ERROR;
+                       } else {
+                               /* found - remove the last 2 args */
+                               argc -= 2;
+                       }
+               }
+       }
+
        fields = malloc(sizeof(scan_field_t) * argc / 2);
 
        for (i = 0; i < argc / 2; i++)
@@ -2789,14 +2903,14 @@ int handle_irscan_command(struct command_context_s *cmd_ctx, char *cmd, char **a
                fields[i].tap = tap;
                fields[i].out_value = malloc(CEIL(field_size, 8));
                buf_set_u32(fields[i].out_value, 0, field_size, strtoul(args[i*2+1], NULL, 0));
-               fields[i].out_mask = NULL;
                fields[i].in_value = NULL;
-               fields[i].in_check_mask = NULL;
-               fields[i].in_handler = NULL;
-               fields[i].in_handler_priv = NULL;
        }
 
-       jtag_add_ir_scan(argc / 2, fields, -1);
+       jtag_add_ir_scan(argc / 2, fields, TAP_INVALID);
+       /* did we have an endstate? */
+       if (endstate != TAP_INVALID)
+               jtag_add_end_state(endstate);
+
        jtag_execute_queue();
 
        for (i = 0; i < argc / 2; i++)
@@ -2807,7 +2921,7 @@ int handle_irscan_command(struct command_context_s *cmd_ctx, char *cmd, char **a
        return ERROR_OK;
 }
 
-int Jim_Command_drscan(Jim_Interp *interp, int argc, Jim_Obj *const *args)
+static int Jim_Command_drscan(Jim_Interp *interp, int argc, Jim_Obj *const *args)
 {
        int retval;
        scan_field_t *fields;
@@ -2815,11 +2929,16 @@ int Jim_Command_drscan(Jim_Interp *interp, int argc, Jim_Obj *const *args)
        int field_count = 0;
        int i, e;
        jtag_tap_t *tap;
+       tap_state_t endstate;
 
        /* args[1] = device
         * args[2] = num_bits
         * args[3] = hex string
         * ... repeat num bits and hex string ...
+        *
+        * .. optionally:
+       *     args[N-2] = "-endstate"
+        *     args[N-1] = statename
         */
        if ((argc < 4) || ((argc % 2)!=0))
        {
@@ -2827,14 +2946,54 @@ int Jim_Command_drscan(Jim_Interp *interp, int argc, Jim_Obj *const *args)
                return JIM_ERR;
        }
 
+       /* assume no endstate */
+       endstate = TAP_INVALID;
+       /* validate arguments as numbers */
+       e = JIM_OK;
        for (i = 2; i < argc; i+=2)
        {
                long bits;
+               const char *cp;
 
                e = Jim_GetLong(interp, args[i], &bits);
-               if (e != JIM_OK)
+               /* If valid - try next arg */
+               if( e == JIM_OK ){
+                       continue;
+               }
+
+               /* Not valid.. are we at the end? */
+               if ( ((i+2) != argc) ){
+                       /* nope, then error */
                        return e;
-       }
+               }
+
+               /* it could be: "-endstate FOO" */
+
+               /* get arg as a string. */
+               cp = Jim_GetString( args[i], NULL );
+               /* is it the magic? */
+               if( 0 == strcmp( "-endstate", cp ) ){
+                       /* is the statename valid? */
+                       cp = Jim_GetString( args[i+1], NULL );
+
+                       /* see if it is a valid state name */
+                       endstate = tap_state_by_name(cp);
+                       if( endstate < 0 ){
+                               /* update the error message */
+                               Jim_SetResult_sprintf(interp,"endstate: %s invalid", cp );
+                       } else {
+                               /* valid - so clear the error */
+                               e = JIM_OK;
+                               /* and remove the last 2 args */
+                               argc -= 2;
+                       }
+               }
+
+               /* Still an error? */
+               if( e != JIM_OK ){
+                       return e; /* too bad */
+               }
+       } /* validate args */
 
        tap = jtag_TapByJimObj( interp, args[1] );
        if( tap == NULL ){
@@ -2856,15 +3015,15 @@ int Jim_Command_drscan(Jim_Interp *interp, int argc, Jim_Obj *const *args)
                fields[field_count].num_bits = bits;
                fields[field_count].out_value = malloc(CEIL(bits, 8));
                str_to_buf(str, len, fields[field_count].out_value, bits, 0);
-               fields[field_count].out_mask = NULL;
                fields[field_count].in_value = fields[field_count].out_value;
-               fields[field_count].in_check_mask = NULL;
-               fields[field_count].in_check_value = NULL;
-               fields[field_count].in_handler = NULL;
-               fields[field_count++].in_handler_priv = NULL;
+               field_count++;
        }
 
-       jtag_add_dr_scan(num_fields, fields, -1);
+       jtag_add_dr_scan(num_fields, fields, TAP_INVALID);
+       /* did we get an end state? */
+       if (endstate != TAP_INVALID)
+               jtag_add_end_state(endstate);
+
        retval = jtag_execute_queue();
        if (retval != ERROR_OK)
        {
@@ -2895,7 +3054,16 @@ int Jim_Command_drscan(Jim_Interp *interp, int argc, Jim_Obj *const *args)
        return JIM_OK;
 }
 
-int handle_verify_ircapture_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
+
+static int Jim_Command_flush_count(Jim_Interp *interp, int argc, Jim_Obj *const *args)
+{
+       Jim_SetResult(interp, Jim_NewIntObj(interp, jtag_flush_queue_count));
+
+       return JIM_OK;
+}
+
+
+static int handle_verify_ircapture_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
 {
        if (argc == 1)
        {
@@ -2961,16 +3129,317 @@ void jtag_tap_handle_event( jtag_tap_t * tap, enum jtag_tap_event e)
        }
 }
 
+/*-----<Cable Helper API>---------------------------------------*/
+
+/*  these Cable Helper API functions are all documented in the jtag.h header file,
+       using a Doxygen format.  And since Doxygen's configuration file "Doxyfile",
+       is setup to prefer its docs in the header file, no documentation is here, for
+       if it were, it would have to be doubly maintained.
+*/
+
+/**
+ * @see tap_set_state() and tap_get_state() accessors.
+ * Actual name is not important since accessors hide it.
+ */
+static tap_state_t state_follower = TAP_RESET;
+
+void tap_set_state_impl( tap_state_t new_state )
+{
+       /* this is the state we think the TAPs are in now, was cur_state */
+       state_follower = new_state;
+}
+
+tap_state_t tap_get_state()
+{
+       return state_follower;
+}
+
+/**
+ * @see tap_set_end_state() and tap_get_end_state() accessors.
+ * Actual name is not important because accessors hide it.
+ */
+static tap_state_t end_state_follower = TAP_RESET;
+
+void tap_set_end_state( tap_state_t new_end_state )
+{
+       /* this is the state we think the TAPs will be in at completion of the
+          current TAP operation, was end_state
+       */
+       end_state_follower = new_end_state;
+}
+
+tap_state_t tap_get_end_state()
+{
+       return end_state_follower;
+}
+
+
+int tap_move_ndx( tap_state_t astate )
+{
+       /* given a stable state, return the index into the tms_seqs[] array within tap_get_tms_path() */
+
+       int ndx;
+
+       switch( astate )
+       {
+       case TAP_RESET:         ndx = 0;                        break;
+       case TAP_DRSHIFT:       ndx = 2;                        break;
+       case TAP_DRPAUSE:       ndx = 3;                        break;
+       case TAP_IDLE:          ndx = 1;                        break;
+       case TAP_IRSHIFT:       ndx = 4;                        break;
+       case TAP_IRPAUSE:       ndx = 5;                        break;
+       default:
+               LOG_ERROR( "fatal: unstable state \"%s\" used in tap_move_ndx()", tap_state_name(astate) );
+               exit(1);
+       }
+
+       return ndx;
+}
+
+
+/* tap_move[i][j]: tap movement command to go from state i to state j
+ * 0: Test-Logic-Reset
+ * 1: Run-Test/Idle
+ * 2: Shift-DR
+ * 3: Pause-DR
+ * 4: Shift-IR
+ * 5: Pause-IR
+ *
+ * DRSHIFT->DRSHIFT and IRSHIFT->IRSHIFT have to be caught in interface specific code
+ */
+static struct
+{
+       u8      bits;
+       u8      bit_count;
+
+} tms_seqs[6][6] =             /*  [from_state_ndx][to_state_ndx] */
+{
+       /* value clocked to TMS to move from one of six stable states to another.
+        * N.B. OOCD clocks TMS from LSB first, so read these right-to-left.
+        * N.B. These values are tightly bound to the table in tap_get_tms_path_len().
+        * N.B. Reset only needs to be 0b11111, but in JLink an even byte of 1's is more stable.
+        *              These extra ones cause no TAP state problem, because we go into reset and stay in reset.
+        */
+
+/*
+ * These macros allow us to specify TMS state transitions by bits rather than hex bytes.
+ * Read the bits from LSBit first to MSBit last (right-to-left).
+ */
+#define HEX__(n) 0x##n##LU
+
+#define B8__(x) \
+        (((x) & 0x0000000FLU)?(1<<0):0) \
+       +(((x) & 0x000000F0LU)?(1<<1):0) \
+       +(((x) & 0x00000F00LU)?(1<<2):0) \
+       +(((x) & 0x0000F000LU)?(1<<3):0) \
+       +(((x) & 0x000F0000LU)?(1<<4):0) \
+       +(((x) & 0x00F00000LU)?(1<<5):0) \
+       +(((x) & 0x0F000000LU)?(1<<6):0) \
+       +(((x) & 0xF0000000LU)?(1<<7):0)
+
+#define B8(bits,count)         { ((u8)B8__(HEX__(bits))), (count) }
+
+#if 0 && ((BUILD_FT2232_FTD2XX==1) || (BUILD_FT2232_LIBFTDI==1) || (BUILD_JLINK==1))
+       /*      this is the table submitted by Jeff Williams on 3/30/2009 with this comment:
+
+               OK, I added Peter's version of the state table, and it works OK for
+               me on MC1322x. I've recreated the jlink portion of patch with this
+               new state table. His changes to my state table are pretty minor in
+               terms of total transitions, but Peter feels that his version fixes
+               some long-standing problems.
+               Jeff
+
+               I added the bit count into the table, reduced RESET column to 7 bits from 8.
+               Dick
+
+               state specific comments:
+               ------------------------
+               *->RESET                   tried the 5 bit reset and it gave me problems, 7 bits seems to
+                                          work better on ARM9 with ft2232 driver.  (Dick)
+
+               RESET->DRSHIFT add 1 extra clock cycles in the RESET state before advancing.
+                                               needed on ARM9 with ft2232 driver.  (Dick)
+
+               RESET->IRSHIFT add 1 extra clock cycles in the RESET state before advancing.
+                                               needed on ARM9 with ft2232 driver.  (Dick)
+       */
+
+       /* to state: */
+       /*      RESET                   IDLE                            DRSHIFT                 DRPAUSE                 IRSHIFT                 IRPAUSE */                      /* from state: */
+       {       B8(1111111,7),  B8(0,1),                        B8(00101,5),    B8(01010,5),            B8(001101,6),   B8(010110,6) },         /* RESET */
+       {       B8(1111111,7),  B8(0,1),                        B8(001,3),              B8(0101,4),             B8(0011,4),     B8(01011,5) },          /* IDLE */
+       {       B8(1111111,7),  B8(011,3),              B8(00111,5),            B8(01,2),               B8(001111,6),   B8(0101111,7) },                /* DRSHIFT */
+       {       B8(1111111,7),  B8(011,3),              B8(01,2),               B8(0,1),                        B8(001111,6),   B8(0101111,7) },                /* DRPAUSE */
+       {       B8(1111111,7),  B8(011,3),              B8(00111,5),            B8(010111,6),   B8(001111,6),   B8(01,2) },                     /* IRSHIFT */
+       {       B8(1111111,7),  B8(011,3),              B8(00111,5),            B8(010111,6),   B8(01,2),               B8(0,1) }                       /* IRPAUSE */
+
+#else  /* this is the old table, converted from hex and with the bit_count set to 7 for each combo, like before */
+
+       /* to state: */
+       /*      RESET                   IDLE                            DRSHIFT                 DRPAUSE                 IRSHIFT                 IRPAUSE */                      /* from state: */
+       {       B8(1111111,7),  B8(0000000,7),  B8(0010111,7),  B8(0001010,7),  B8(0011011,7),  B8(0010110,7) },                /* RESET */
+       {       B8(1111111,7),  B8(0000000,7),  B8(0100101,7),  B8(0000101,7),  B8(0101011,7),  B8(0001011,7) },                /* IDLE */
+       {       B8(1111111,7),  B8(0110001,7),  B8(0000000,7),  B8(0000001,7),  B8(0001111,7),  B8(0101111,7) },                /* DRSHIFT */
+       {       B8(1111111,7),  B8(0110000,7),  B8(0100000,7),  B8(0010111,7),  B8(0011110,7),  B8(0101111,7) },                /* DRPAUSE */
+       {       B8(1111111,7),  B8(0110001,7),  B8(0000111,7),  B8(0010111,7),  B8(0000000,7),  B8(0000001,7) },                /* IRSHIFT */
+       {       B8(1111111,7),  B8(0110000,7),  B8(0011100,7),  B8(0010111,7),  B8(0100000,7),  B8(0101111,7) }                 /* IRPAUSE */
+
+#endif
+
+#if 0 /* keeping old hex stuff for awhile, for reference */
+       /* RESET                        IDLE                    DRSHIFT                 DRPAUSE                 IRSHIFT                 IRPAUSE */
+       {  0x7f,                        0x00,                   0x17,                   0x0a,                   0x1b,                   0x16 }, /* RESET */
+       {  0x7f,                        0x00,                   0x25,                   0x05,                   0x2b,                   0x0b }, /* IDLE */
+       {  0x7f,                        0x31,                   0x00,                   0x01,                   0x0f,                   0x2f }, /* DRSHIFT  */
+       {  0x7f,                        0x30,                   0x20,                   0x17,                   0x1e,                   0x2f }, /* DRPAUSE  */
+       {  0x7f,                        0x31,                   0x07,                   0x17,                   0x00,                   0x01 }, /* IRSHIFT  */
+       {  0x7f,                        0x30,                   0x1c,                   0x17,                   0x20,                   0x2f }  /* IRPAUSE  */
+#endif
+};
+
 
-/* map state number to SVF state string */
-const char* jtag_state_name(enum tap_state state)
+int tap_get_tms_path( tap_state_t from, tap_state_t to )
+{
+       return tms_seqs[tap_move_ndx(from)][tap_move_ndx(to)].bits;
+}
+
+
+int tap_get_tms_path_len( tap_state_t from, tap_state_t to )
+{
+       return tms_seqs[tap_move_ndx(from)][tap_move_ndx(to)].bit_count;
+}
+
+
+bool tap_is_state_stable(tap_state_t astate)
+{
+       bool is_stable;
+
+       /*      A switch() is used because it is symbol dependent
+               (not value dependent like an array), and can also check bounds.
+       */
+       switch( astate )
+       {
+       case TAP_RESET:
+       case TAP_IDLE:
+       case TAP_DRSHIFT:
+       case TAP_DRPAUSE:
+       case TAP_IRSHIFT:
+       case TAP_IRPAUSE:
+               is_stable = true;
+               break;
+       default:
+               is_stable = false;
+       }
+
+       return is_stable;
+}
+
+tap_state_t tap_state_transition(tap_state_t cur_state, bool tms)
+{
+       tap_state_t new_state;
+
+       /*      A switch is used because it is symbol dependent and not value dependent
+               like an array.  Also it can check for out of range conditions.
+       */
+
+       if (tms)
+       {
+               switch (cur_state)
+               {
+               case TAP_RESET:
+                       new_state = cur_state;
+                       break;
+               case TAP_IDLE:
+               case TAP_DRUPDATE:
+               case TAP_IRUPDATE:
+                       new_state = TAP_DRSELECT;
+                       break;
+               case TAP_DRSELECT:
+                       new_state = TAP_IRSELECT;
+                       break;
+               case TAP_DRCAPTURE:
+               case TAP_DRSHIFT:
+                       new_state = TAP_DREXIT1;
+                       break;
+               case TAP_DREXIT1:
+               case TAP_DREXIT2:
+                       new_state = TAP_DRUPDATE;
+                       break;
+               case TAP_DRPAUSE:
+                       new_state = TAP_DREXIT2;
+                       break;
+               case TAP_IRSELECT:
+                       new_state = TAP_RESET;
+                       break;
+               case TAP_IRCAPTURE:
+               case TAP_IRSHIFT:
+                       new_state = TAP_IREXIT1;
+                       break;
+               case TAP_IREXIT1:
+               case TAP_IREXIT2:
+                       new_state = TAP_IRUPDATE;
+                       break;
+               case TAP_IRPAUSE:
+                       new_state = TAP_IREXIT2;
+                       break;
+               default:
+                       LOG_ERROR( "fatal: invalid argument cur_state=%d", cur_state );
+                       exit(1);
+                       break;
+               }
+       }
+       else
+       {
+               switch (cur_state)
+               {
+               case TAP_RESET:
+               case TAP_IDLE:
+               case TAP_DRUPDATE:
+               case TAP_IRUPDATE:
+                       new_state = TAP_IDLE;
+                       break;
+               case TAP_DRSELECT:
+                       new_state = TAP_DRCAPTURE;
+                       break;
+               case TAP_DRCAPTURE:
+               case TAP_DRSHIFT:
+               case TAP_DREXIT2:
+                       new_state = TAP_DRSHIFT;
+                       break;
+               case TAP_DREXIT1:
+               case TAP_DRPAUSE:
+                       new_state = TAP_DRPAUSE;
+                       break;
+               case TAP_IRSELECT:
+                       new_state = TAP_IRCAPTURE;
+                       break;
+               case TAP_IRCAPTURE:
+               case TAP_IRSHIFT:
+               case TAP_IREXIT2:
+                       new_state = TAP_IRSHIFT;
+                       break;
+               case TAP_IREXIT1:
+               case TAP_IRPAUSE:
+                       new_state = TAP_IRPAUSE;
+                       break;
+               default:
+                       LOG_ERROR( "fatal: invalid argument cur_state=%d", cur_state );
+                       exit(1);
+                       break;
+               }
+       }
+
+       return new_state;
+}
+
+const char* tap_state_name(tap_state_t state)
 {
        const char* ret;
 
        switch( state )
        {
        case TAP_RESET:         ret = "RESET";                  break;
-       case TAP_IDLE:          ret = "IDLE";                   break;
+       case TAP_IDLE:          ret = "RUN/IDLE";               break;
        case TAP_DRSELECT:      ret = "DRSELECT";               break;
        case TAP_DRCAPTURE: ret = "DRCAPTURE";          break;
        case TAP_DRSHIFT:       ret = "DRSHIFT";                        break;
@@ -2991,3 +3460,103 @@ const char* jtag_state_name(enum tap_state state)
        return ret;
 }
 
+static tap_state_t tap_state_by_name( const char *name )
+{
+       tap_state_t x;
+
+       for( x = 0 ; x < TAP_NUM_STATES ; x++ ){
+               /* be nice to the human */
+               if( 0 == strcasecmp( name, tap_state_name(x) ) ){
+                       return x;
+               }
+       }
+       /* not found */
+       return TAP_INVALID;
+}
+
+#ifdef _DEBUG_JTAG_IO_
+
+#define JTAG_DEBUG_STATE_APPEND(buf, len, bit) \
+               do { buf[len] = bit ? '1' : '0'; } while(0)
+#define JTAG_DEBUG_STATE_PRINT(a, b, astr, bstr) \
+               DEBUG_JTAG_IO("TAP/SM: %9s -> %5s\tTMS: %s\tTDI: %s", \
+                       tap_state_name(a), tap_state_name(b), astr, bstr)
+
+tap_state_t jtag_debug_state_machine(const void *tms_buf, const void *tdi_buf,
+               unsigned tap_bits, tap_state_t next_state)
+{
+       const u8 *tms_buffer;
+       const u8 *tdi_buffer;
+       unsigned tap_bytes;
+       unsigned cur_byte;
+       unsigned cur_bit;
+
+       unsigned tap_out_bits;
+       char tms_str[33];
+       char tdi_str[33];
+
+       tap_state_t last_state;
+
+       // set startstate (and possibly last, if tap_bits == 0)
+       last_state = next_state;
+       DEBUG_JTAG_IO("TAP/SM: START state: %s", tap_state_name(next_state));
+
+       tms_buffer = (const u8 *)tms_buf;
+       tdi_buffer = (const u8 *)tdi_buf;
+
+       tap_bytes = TAP_SCAN_BYTES(tap_bits);
+       DEBUG_JTAG_IO("TAP/SM: TMS bits: %u (bytes: %u)", tap_bits, tap_bytes);
+
+       tap_out_bits = 0;
+       for(cur_byte = 0; cur_byte < tap_bytes; cur_byte++)
+       {
+               for(cur_bit = 0; cur_bit < 8; cur_bit++)
+               {
+                       // make sure we do not run off the end of the buffers
+                       unsigned tap_bit = cur_byte * 8 + cur_bit;
+                       if (tap_bit == tap_bits)
+                               break;
+
+                       // check and save TMS bit
+                       tap_bit = !!(tms_buffer[cur_byte] & (1 << cur_bit));
+                       JTAG_DEBUG_STATE_APPEND(tms_str, tap_out_bits, tap_bit);
+
+                       // use TMS bit to find the next TAP state
+                       next_state = tap_state_transition(last_state, tap_bit);
+
+                       // check and store TDI bit
+                       tap_bit = !!(tdi_buffer[cur_byte] & (1 << cur_bit));
+                       JTAG_DEBUG_STATE_APPEND(tdi_str, tap_out_bits, tap_bit);
+
+                       // increment TAP bits
+                       tap_out_bits++;
+
+                       // Only show TDO bits on state transitions, or
+                       // after some number of bits in the same state.
+                       if ((next_state == last_state) && (tap_out_bits < 32))
+                               continue;
+
+                       // terminate strings and display state transition
+                       tms_str[tap_out_bits] = tdi_str[tap_out_bits] = 0;
+                       JTAG_DEBUG_STATE_PRINT(last_state, next_state, tms_str, tdi_str);
+
+                       // reset state
+                       last_state = next_state;
+                       tap_out_bits = 0;
+               }
+       }
+
+       if (tap_out_bits)
+       {
+               // terminate strings and display state transition
+               tms_str[tap_out_bits] = tdi_str[tap_out_bits] = 0;
+               JTAG_DEBUG_STATE_PRINT(last_state, next_state, tms_str, tdi_str);
+       }
+
+       DEBUG_JTAG_IO("TAP/SM: FINAL state: %s", tap_state_name(next_state));
+
+       return next_state;
+}
+#endif // _DEBUG_JTAG_IO_
+
+/*-----</Cable Helper API>--------------------------------------*/