diff --git a/jtag/ChangeLog b/jtag/ChangeLog
index 94e524c5..4cb3ad0a 100644
--- a/jtag/ChangeLog
+++ b/jtag/ChangeLog
@@ -1,3 +1,120 @@
+2008-02-27  Jie Zhang  <jie.zhang@analog.com>
+
+   * include/bus.h: Don't include chain.h.
+   * include/svf.h: Include chain.h.
+     (svf_run): Add a parameter to pass chain.
+   * include/cmd.h: Include chain.h.
+     (cmd_t): Add a parameter to pass chain for run.
+     (cmd_run, cmd_test_cable): Add a parameter to pass chain.
+   * include/bus_driver.h: Include chain.h.
+     (struct bus_driver): Add a parameter to pass chain for new_bus.
+   * include/bsdl.h: Include chain.h
+     (bsdl_read_file, bsdl_scan_files): Add a parameter to pass chain.
+   * include/jtag.h (chain): Don't declare.
+     (jtag_parse_file): Add a parameter to pass chain.
+   * src/bsdl/bsdl.c (bsdl_read_file): Add a parameter to pass chain.
+       Initialize parser_priv->jtag_ctrl.chain.
+     (bsdl_scan_files): Add a parameter to pass chain.
+   * src/bsdl/bsdl_sem.c (bsdl_set_instruction_length): Call cmd_run
+       with priv->jtag_ctrl.chain.
+   * src/bsdl/bsdl.h (struct jtag_ctrl): Add chain field.
+   * src/detect.c (detect_parts): Pass chain to bsdl_scan_files
+       and cmd_run.
+   * src/bus/bf548_ezkit.c (bf548_ezkit_bus_new): Add a parameter to
+       pass chain.
+   * src/bus/fjmem.c (fjmem_bus_new): Likewise.
+   * src/bus/ppc405ep.c (ppc405ep_bus_new): Likewise.
+   * src/bus/sh7727.c (sh7727_bus_new): Likewise.
+   * src/bus/prototype.c (prototype_bus_new): Likewise.
+   * src/bus/sa1110.c (sa1110_bus_new): Likewise.
+   * src/bus/ppc440gx_ebc8.c (ppc440gx_ebc8_bus_new): Likewise.
+   * src/bus/tx4925.c (tx4925_bus_new): Likewise.
+   * src/bus/sh7750r.c (sh7750r_bus_new): Likewise.
+   * src/bus/pxa2x0.c (pxa2x0_bus_new): Likewise.
+     (pxa27x_bus_new): Likewise.
+   * src/bus/bf533_stamp.c (bf533_stamp_bus_new): Likewise.
+   * src/bus/bf533_ezkit.c (bf533_ezkit_bus_new): Likewise.
+   * src/bus/bf537_stamp.c (bf537_stamp_bus_new): Likewise.
+   * src/bus/ixp425.c (ixp425_bus_new): Likewise.
+   * src/bus/h7202.c (h7202_bus_new): Likewise.
+   * src/bus/zefant-xs3.c (zefant_xs3_bus_new): Likewise.
+   * src/bus/bcm1250.c (bcm1250_bus_new): Likewise.
+   * src/bus/sharc21065l.c (sharc_21065L_bus_new): Likewise.
+   * src/bus/au1500.c (au1500_bus_new): Likewise.
+   * src/bus/lh7a400.c (lh7a400_bus_new): Likewise.
+   * src/bus/sh7751r.c (sh7751r_bus_new): Likewise.
+   * src/bus/mpc5200.c (mpc5200_bus_new): Likewise.
+   * src/bus/jopcyc.c (jopcyc_bus_new): Likewise.
+   * src/bus/slsup3.c (slsup3_bus_new): Likewise.
+   * src/bus/bf561_ezkit.c (bf561_ezkit_bus_new): Likewise.
+   * src/bus/s3c4510x.c (s3c4510_bus_new): Likewise.
+   * src/bus/ejtag.c (ejtag_bus_new): Likewise.
+   * src/bus/mpc824x.c (mpc824x_bus_new): Likewise.
+     (mpc824x_bus_write): Change chain to CHAIN.
+   * src/svf/svf.c (yyparse): Add a parameter to pass chain. And update
+       all call sites.
+     (svf_force_reset_state): Likewise.
+     (svf_goto_state): Likewise.
+     (svf_frequency): Likewise.
+     (svf_runtest): Likewise.
+     (svf_state): Likewise.
+     (svf_sxr): Likewise.
+     (svf_trst): Likewsie.
+     (svf_run): Likewise.
+   * src/svf/svf_bison.y (yyerror): Update declaration and call sites.
+     (chain): %parse-param.
+   * src/svf/svf.h: Include chain.h and update function declarations.
+   * src/cmd/endian.c (cmd_endian_run): Add a parameter to pass chain.
+       And update all call sites.
+   * src/cmd/frequency.c (cmd_frequency_run): Likewise.
+   * src/cmd/part.c (cmd_part_run): Likewise.
+   * src/cmd/salias.c (cmd_salias_run): Likewise.
+   * src/cmd/instruction.c (cmd_instruction_run): Likewise.
+   * src/cmd/quit.c (cmd_quit_run): Likewise.
+   * src/cmd/register.c (cmd_register_run): Likewise.
+   * src/cmd/debug.c (cmd_debug_run): Likewise.
+   * src/cmd/flashmem.c (cmd_flashmem_run): Likewise.
+   * src/cmd/svf.c (cmd_svf_run): Likewise.
+   * src/cmd/peekpoke.c (cmd_peek_run): Likewise.
+     (cmd_poke_run): Likewise.
+   * src/cmd/cmd.c (cmd_test_cable): Likewise.
+     (cmd_run): Likewise.
+   * src/cmd/dr.c (cmd_dr_run): Likewise.
+   * src/cmd/cable.c (cmd_cable_run): Likewise.
+   * src/cmd/shell.c (cmd_shell_run): Likewise.
+   * src/cmd/discovery.c (cmd_discovery_run): Likewise.
+   * src/cmd/detect.c (cmd_detect_run): Likewise.
+   * src/cmd/readmem.c (cmd_readmem_run): Likewise.
+   * src/cmd/signal.c (cmd_signal_run): Likewise.
+   * src/cmd/shift.c (cmd_shift_run): Likewise.
+   * src/cmd/initbus.c (cmd_initbus_run): Likewise.
+   * src/cmd/eraseflash.c (cmd_eraseflash_run): Likewise.
+   * src/cmd/bit.c (cmd_bit_run): Likewise.
+   * src/cmd/get.c (cmd_get_run): Likewise.
+   * src/cmd/test.c (cmd_test_run): Likewise.
+   * src/cmd/reset.c (cmd_reset_run): Likewise.
+   * src/cmd/include.c (cmd_include_or_script_run): Likewise.
+     (cmd_include_run): Likewise.
+     (cmd_script_run): Likewise.
+   * src/cmd/bsdl.c (cmd_bsdl_run): Likewise.
+   * src/cmd/scan.c (cmd_scan_run): Likewise.
+   * src/cmd/detectflash.c (cmd_detectflash_run): Likewise.
+   * src/cmd/help.c (cmd_help_run): Likewise.
+   * src/cmd/writemem.c (cmd_writemem_run): Likewise.
+   * src/cmd/bus.c (cmd_bus_run): Likewise.
+   * src/cmd/set.c (cmd_set_run): Likewise.
+   * src/cmd/print.c (cmd_print_run): Likewise.
+   * src/jtag.c (chain): Don't define.
+     (jtag_parse_line): Add a parameter to pass chain.
+       And update all call sites.
+     (jtag_readline_multiple_commands_support): Likewise.
+     (jtag_readline_loop): Likewise.
+     (jtag_parse_stream): Likewise.
+     (jtag_parse_file): Likewise.
+     (jtag_parse_rc): Likewise.
+     (cleanup): Likewise.
+     (main): Define a local chain.
+
 2008-02-26  Arnim Laeuger  <arniml@users.sourceforge.net>
 
    * src/tap/cable/ft2232.c (send_and_receive): loopback_off moved to ftdi.c/ftd2xx.c
diff --git a/jtag/include/bsdl.h b/jtag/include/bsdl.h
index 86ed407e..2e0193bc 100644
--- a/jtag/include/bsdl.h
+++ b/jtag/include/bsdl.h
@@ -25,10 +25,12 @@
 #ifndef BSDL_H
 #define BSDL_H
 
+#include "chain.h"
+
 extern int bsdl_debug;
 
-int bsdl_read_file(const char *, int, char *);
+int bsdl_read_file(chain_t *, const char *, int, char *);
 void bsdl_set_path(const char *);
-int bsdl_scan_files(const char *, int);
+int bsdl_scan_files(chain_t *, const char *, int);
 
 #endif /* BSDL_H */
diff --git a/jtag/include/bus.h b/jtag/include/bus.h
index b034ad39..304fc6a8 100644
--- a/jtag/include/bus.h
+++ b/jtag/include/bus.h
@@ -27,7 +27,6 @@
 #define	BUS_H
 
 #include <stdint.h>
-#include "chain.h"
 
 #include <bus_driver.h>
 
diff --git a/jtag/include/bus_driver.h b/jtag/include/bus_driver.h
index 1dbb0508..55ff6e19 100644
--- a/jtag/include/bus_driver.h
+++ b/jtag/include/bus_driver.h
@@ -37,6 +37,8 @@
 
 #include <stdint.h>
 
+#include "chain.h"
+
 typedef struct {
 	const char *description;
 	uint32_t start;
@@ -49,7 +51,7 @@ typedef struct bus bus_t;
 typedef struct bus_driver {
 	const char *name;
 	const char *description;
-	bus_t *(*new_bus)( char *cmd_params[] );
+	bus_t *(*new_bus)( chain_t *chain, char *cmd_params[] );
 	void (*free_bus)( bus_t *bus );
 	void (*printinfo)( bus_t *bus );
 	void (*prepare)( bus_t *bus );
diff --git a/jtag/include/cmd.h b/jtag/include/cmd.h
index 39ab240b..4629a763 100644
--- a/jtag/include/cmd.h
+++ b/jtag/include/cmd.h
@@ -34,18 +34,20 @@
 #ifndef CMD_H
 #define CMD_H
 
+#include "chain.h"
+
 typedef struct {
 	char *name;
 	char *desc;
 	void (*help)( void );
-	int (*run)( char *params[] );
+	int (*run)( chain_t *chain, char *params[] );
 } cmd_t;
 
 extern const cmd_t *cmds[];
 
-int cmd_run( char *params[] );
+int cmd_run( chain_t *chain, char *params[] );
 int cmd_params( char *params[] );
 int cmd_get_number( char *s, unsigned int *i );
-int cmd_test_cable( void );
+int cmd_test_cable( chain_t *chain );
 
 #endif /* CMD_H */
diff --git a/jtag/include/jtag.h b/jtag/include/jtag.h
index 967f374f..ee2af1b9 100644
--- a/jtag/include/jtag.h
+++ b/jtag/include/jtag.h
@@ -34,12 +34,11 @@
 #include "bus.h"
 #include "part.h"
 
-extern chain_t *chain;
 extern bus_t *bus;
 extern int big_endian;
 extern int debug_mode;
 
-int jtag_parse_file( const char *filename );
+int jtag_parse_file( chain_t *chain, const char *filename );
 
 int detect_parts( chain_t *chain, char *db_path );
 int detect_register_size( chain_t *chain );
diff --git a/jtag/include/svf.h b/jtag/include/svf.h
index 56e99e06..5d91dd14 100644
--- a/jtag/include/svf.h
+++ b/jtag/include/svf.h
@@ -25,6 +25,8 @@
 #ifndef SVF_H
 #define SVF_H
 
-void svf_run(FILE *, int);
+#include "chain.h"
+
+void svf_run(chain_t *chain, FILE *, int);
 
 #endif /* SVF_H */
diff --git a/jtag/src/bsdl/bsdl.c b/jtag/src/bsdl/bsdl.c
index 56a80482..7cc4aa74 100644
--- a/jtag/src/bsdl/bsdl.c
+++ b/jtag/src/bsdl/bsdl.c
@@ -87,7 +87,7 @@ void bsdl_msg(int type, const char *format, ...)
  * > 0 : No errors, idcode checked and matched
  *
  ****************************************************************************/
-int bsdl_read_file(const char *BSDL_File_Name, int mode, const char *idcode)
+int bsdl_read_file(chain_t *chain, const char *BSDL_File_Name, int mode, const char *idcode)
 {
   FILE *BSDL_File;
   parser_priv_t *parser_priv;
@@ -124,11 +124,16 @@ int bsdl_read_file(const char *BSDL_File_Name, int mode, const char *idcode)
 	  fclose(BSDL_File);
 	  return -1;
 	}
+	parser_priv->jtag_ctrl.chain = chain;
 	parser_priv->jtag_ctrl.part = chain->parts->parts[chain->active_part];
-      } else
+      } else {
+	parser_priv->jtag_ctrl.chain = NULL;
 	parser_priv->jtag_ctrl.part = NULL;
-    } else
+      }
+    } else {
+      parser_priv->jtag_ctrl.chain = NULL;
       parser_priv->jtag_ctrl.part = NULL;
+    }
 
     parser_priv->jtag_ctrl.idcode = NULL;
 
@@ -250,7 +255,7 @@ void bsdl_set_path(const char *pathlist)
  * > 0 : No errors, idcode checked and matched
  *
  ****************************************************************************/
-int bsdl_scan_files(const char *idcode, int mode)
+int bsdl_scan_files(chain_t *chain, const char *idcode, int mode)
 {
   int idx = 0;
   int result = 0;
@@ -282,14 +287,14 @@ int bsdl_scan_files(const char *idcode, int mode)
 	      if (mode >= 1) {
 		/* now we know we can finally read the file */
 		/* do a test read first */
-		result = bsdl_read_file(name, -1, idcode);
+		result = bsdl_read_file(chain, name, -1, idcode);
 		if (result > 0) {
 		  /* read in BSDL file if IDCODE matched */
 		  printf( _("  Filename:     %s\n"), name );
-		  result = bsdl_read_file(name, 1, idcode);
+		  result = bsdl_read_file(chain, name, 1, idcode);
 		}
 	      } else
-		result = bsdl_read_file(name, mode, idcode);
+		result = bsdl_read_file(chain, name, mode, idcode);
             }
           }
 
diff --git a/jtag/src/bsdl/bsdl.h b/jtag/src/bsdl/bsdl.h
index 0327d47f..92487984 100644
--- a/jtag/src/bsdl/bsdl.h
+++ b/jtag/src/bsdl/bsdl.h
@@ -116,6 +116,7 @@ struct jtag_ctrl {
     int     mode;
     int     debug;
     char   *idcode;       /* IDCODE string */
+    chain_t *chain;
     part_t *part;
     struct  port_desc port_desc;
     struct  cell_info cell_info;
diff --git a/jtag/src/bsdl/bsdl_sem.c b/jtag/src/bsdl/bsdl_sem.c
index eb960ce2..23ed211e 100644
--- a/jtag/src/bsdl/bsdl_sem.c
+++ b/jtag/src/bsdl/bsdl_sem.c
@@ -237,7 +237,7 @@ void bsdl_set_instruction_length(parser_priv_t *priv, int len)
     lenstring[5] = '\0';
 
     if (priv->jtag_ctrl.mode >= 1)
-      cmd_run(cmd);
+      cmd_run(priv->jtag_ctrl.chain, cmd);
     else
       print_cmd(cmd);
   }
@@ -375,7 +375,7 @@ void bsdl_prt_apply_port(parser_priv_t *priv)
           port_string[str_len-1] = '\0';
 
           if (priv->jtag_ctrl.mode >= 1)
-            cmd_run(cmd);
+            cmd_run(priv->jtag_ctrl.chain, cmd);
           else
             print_cmd(cmd);
         }
@@ -426,7 +426,7 @@ static void create_register(parser_priv_t *priv, char *reg_name, size_t len)
     snprintf(len_str, str_len, "%i", len);
 
     if (priv->jtag_ctrl.mode >= 1)
-      cmd_run(cmd);
+      cmd_run(priv->jtag_ctrl.chain, cmd);
     else
       print_cmd(cmd);
   }
@@ -712,7 +712,7 @@ void bsdl_ci_apply_cell_info(parser_priv_t *priv, int bit_num)
       cmd[5] = NULL;
 
     if (priv->jtag_ctrl.mode >= 1)
-      cmd_run(cmd);
+      cmd_run(priv->jtag_ctrl.chain, cmd);
     else
       print_cmd(cmd);
   }
@@ -932,7 +932,7 @@ void bsdl_ac_finalize(parser_priv_t *priv)
                        NULL};
 
         if (priv->jtag_ctrl.mode >= 1)
-          cmd_run(cmd);
+          cmd_run(priv->jtag_ctrl.chain, cmd);
         else
           print_cmd(cmd);
       }
diff --git a/jtag/src/bus/au1500.c b/jtag/src/bus/au1500.c
index 0c40ccb5..bc4d6b90 100644
--- a/jtag/src/bus/au1500.c
+++ b/jtag/src/bus/au1500.c
@@ -114,7 +114,7 @@ setup_data( bus_t *bus, uint32_t d)
 		part_set_signal( p, RD[i], 1, ( d>>i ) & 1 );
 }
 
-static bus_t *au1500_bus_new( char *cmd_params[] )
+static bus_t *au1500_bus_new( chain_t *chain, char *cmd_params[] )
 {
 	bus_t *bus;
 	char buff[10];
diff --git a/jtag/src/bus/bcm1250.c b/jtag/src/bus/bcm1250.c
index d7cd5296..f22576a1 100644
--- a/jtag/src/bus/bcm1250.c
+++ b/jtag/src/bus/bcm1250.c
@@ -268,7 +268,7 @@ bcm1250_bus_free( bus_t *bus )
 	free( bus );
 }
 
-static bus_t *bcm1250_bus_new( char *cmd_params[] );
+static bus_t *bcm1250_bus_new( chain_t *chain, char *cmd_params[] );
 
 const bus_driver_t bcm1250_bus = {
 	"bcm1250",
@@ -287,7 +287,7 @@ const bus_driver_t bcm1250_bus = {
 };
 
 static bus_t *
-bcm1250_bus_new( char *cmd_params[] )
+bcm1250_bus_new( chain_t *chain, char *cmd_params[] )
 {
     bus_t *bus;
     char buff[10];
diff --git a/jtag/src/bus/bf533_ezkit.c b/jtag/src/bus/bf533_ezkit.c
index fc98fce7..aa0f0b14 100644
--- a/jtag/src/bus/bf533_ezkit.c
+++ b/jtag/src/bus/bf533_ezkit.c
@@ -252,7 +252,7 @@ bf533_ezkit_bus_free( bus_t *bus )
 	free( bus );
 }
 
-static bus_t *bf533_ezkit_bus_new( char *cmd_params[] );
+static bus_t *bf533_ezkit_bus_new( chain_t *chain, char *cmd_params[] );
 
 const bus_driver_t bf533_ezkit_bus = {
 	"bf533_ezkit",
@@ -270,7 +270,7 @@ const bus_driver_t bf533_ezkit_bus = {
 };
 
 static bus_t *
-bf533_ezkit_bus_new( char *cmd_params[] )
+bf533_ezkit_bus_new( chain_t *chain, char *cmd_params[] )
 {
 	bus_t *bus;
 	char buff[15];
diff --git a/jtag/src/bus/bf533_stamp.c b/jtag/src/bus/bf533_stamp.c
index bb866e0b..6b5de3e0 100644
--- a/jtag/src/bus/bf533_stamp.c
+++ b/jtag/src/bus/bf533_stamp.c
@@ -252,7 +252,7 @@ bf533_stamp_bus_free( bus_t *bus )
 	free( bus );
 }
 
-static bus_t *bf533_stamp_bus_new( char *cmd_params[] );
+static bus_t *bf533_stamp_bus_new( chain_t *chain, char *cmd_params[] );
 
 const bus_driver_t bf533_stamp_bus = {
 	"bf533_stamp",
@@ -270,7 +270,7 @@ const bus_driver_t bf533_stamp_bus = {
 };
 
 static bus_t *
-bf533_stamp_bus_new( char *cmd_params[] )
+bf533_stamp_bus_new( chain_t *chain, char *cmd_params[] )
 {
 	bus_t *bus;
 	char buff[15];
diff --git a/jtag/src/bus/bf537_stamp.c b/jtag/src/bus/bf537_stamp.c
index 115252bd..7123683b 100644
--- a/jtag/src/bus/bf537_stamp.c
+++ b/jtag/src/bus/bf537_stamp.c
@@ -263,7 +263,7 @@ bf537_stamp_bus_free( bus_t *bus )
 	free( bus );
 }
 
-static bus_t *bf537_stamp_bus_new( char *cmd_params[] );
+static bus_t *bf537_stamp_bus_new( chain_t *chain, char *cmd_params[] );
 
 const bus_driver_t bf537_stamp_bus = {
 	"bf537_stamp",
@@ -297,7 +297,7 @@ const bus_driver_t bf537_ezkit_bus = {
 
 
 static bus_t *
-bf537_stamp_bus_new( char *cmd_params[] )
+bf537_stamp_bus_new( chain_t *chain, char *cmd_params[] )
 {
 	bus_t *bus;
 	char buff[15];
diff --git a/jtag/src/bus/bf548_ezkit.c b/jtag/src/bus/bf548_ezkit.c
index 892d607c..1d95c07d 100644
--- a/jtag/src/bus/bf548_ezkit.c
+++ b/jtag/src/bus/bf548_ezkit.c
@@ -237,7 +237,7 @@ bf548_ezkit_bus_free( bus_t *bus )
 	free( bus );
 }
 
-static bus_t *bf548_ezkit_bus_new( char *cmd_params[] );
+static bus_t *bf548_ezkit_bus_new( chain_t *chain, char *cmd_params[] );
 
 const bus_driver_t bf548_ezkit_bus = {
 	"bf548_ezkit",
@@ -256,7 +256,7 @@ const bus_driver_t bf548_ezkit_bus = {
 
 
 static bus_t *
-bf548_ezkit_bus_new( char *cmd_params[] )
+bf548_ezkit_bus_new( chain_t *chain, char *cmd_params[] )
 {
 	bus_t *bus;
 	char buff[15];
diff --git a/jtag/src/bus/bf561_ezkit.c b/jtag/src/bus/bf561_ezkit.c
index 9c4e5263..4e613255 100644
--- a/jtag/src/bus/bf561_ezkit.c
+++ b/jtag/src/bus/bf561_ezkit.c
@@ -260,7 +260,7 @@ bf561_ezkit_bus_free( bus_t *bus )
 	free( bus );
 }
 
-static bus_t *bf561_ezkit_bus_new( char *cmd_params[] );
+static bus_t *bf561_ezkit_bus_new( chain_t *chain, char *cmd_params[] );
 
 const bus_driver_t bf561_ezkit_bus = {
 	"bf561_ezkit",
@@ -278,7 +278,7 @@ const bus_driver_t bf561_ezkit_bus = {
 };
 
 static bus_t *
-bf561_ezkit_bus_new( char *cmd_params[] )
+bf561_ezkit_bus_new( chain_t *chain, char *cmd_params[] )
 {
 	bus_t *bus;
 	char buff[15];
diff --git a/jtag/src/bus/ejtag.c b/jtag/src/bus/ejtag.c
index 5f3df2a0..93e79649 100644
--- a/jtag/src/bus/ejtag.c
+++ b/jtag/src/bus/ejtag.c
@@ -449,7 +449,7 @@ ejtag_bus_free( bus_t *bus )
 	free( bus );
 }
 
-static bus_t *ejtag_bus_new( char *cmd_params[] );
+static bus_t *ejtag_bus_new( chain_t *chain, char *cmd_params[] );
 
 const bus_driver_t ejtag_bus = {
 	"ejtag",
@@ -467,7 +467,7 @@ const bus_driver_t ejtag_bus = {
 };
 
 static bus_t *
-ejtag_bus_new( char *cmd_params[] )
+ejtag_bus_new( chain_t *chain, char *cmd_params[] )
 {
 	bus_t *bus;
 
diff --git a/jtag/src/bus/fjmem.c b/jtag/src/bus/fjmem.c
index cefe9068..0673c9d4 100644
--- a/jtag/src/bus/fjmem.c
+++ b/jtag/src/bus/fjmem.c
@@ -643,7 +643,7 @@ fjmem_query_blocks( chain_t *chain, part_t *part, bus_t *bus )
 }
 
 static bus_t *
-fjmem_bus_new( char *params[] )
+fjmem_bus_new( chain_t *chain, char *params[] )
 {
 	bus_t *bus = NULL;
 	int failed = 0;
diff --git a/jtag/src/bus/h7202.c b/jtag/src/bus/h7202.c
index 355d85e9..2aa578fb 100644
--- a/jtag/src/bus/h7202.c
+++ b/jtag/src/bus/h7202.c
@@ -236,7 +236,7 @@ h7202_bus_free( bus_t *bus )
 	free( bus );
 }
 
-static bus_t *h7202_bus_new( char *cmd_params[] );
+static bus_t *h7202_bus_new( chain_t *chain, char *cmd_params[] );
 
 const bus_driver_t h7202_bus = {
 	"h7202",
@@ -254,7 +254,7 @@ const bus_driver_t h7202_bus = {
 };
 
 static bus_t *
-h7202_bus_new( char *cmd_params[] )
+h7202_bus_new( chain_t *chain, char *cmd_params[] )
 {
 	bus_t *bus;
 	char buff[10];
diff --git a/jtag/src/bus/ixp425.c b/jtag/src/bus/ixp425.c
index 4f750d8f..19f4bf35 100644
--- a/jtag/src/bus/ixp425.c
+++ b/jtag/src/bus/ixp425.c
@@ -231,7 +231,7 @@ ixp425_bus_free( bus_t *bus )
 	free( bus );
 }
 
-static bus_t *ixp425_bus_new( char *cmd_params[] );
+static bus_t *ixp425_bus_new( chain_t *chain, char *cmd_params[] );
 
 const bus_driver_t ixp425_bus = {
 	"ixp425",
@@ -250,7 +250,7 @@ const bus_driver_t ixp425_bus = {
 };
 
 static bus_t *
-ixp425_bus_new( char *cmd_params[] )
+ixp425_bus_new( chain_t *chain, char *cmd_params[] )
 {
 	bus_t *bus;
 	char buff[15];
diff --git a/jtag/src/bus/jopcyc.c b/jtag/src/bus/jopcyc.c
index 2a24acda..dc2c9f10 100644
--- a/jtag/src/bus/jopcyc.c
+++ b/jtag/src/bus/jopcyc.c
@@ -500,7 +500,7 @@ attach_sig( bus_t *bus, signal_t **sig, char *id )
 }
 
 static bus_t *
-jopcyc_bus_new( char *cmd_params[] )
+jopcyc_bus_new( chain_t *chain, char *cmd_params[] )
 {
 	bus_t *bus;
 	int failed = 0;
diff --git a/jtag/src/bus/lh7a400.c b/jtag/src/bus/lh7a400.c
index e04c4ba1..b1d8c567 100644
--- a/jtag/src/bus/lh7a400.c
+++ b/jtag/src/bus/lh7a400.c
@@ -257,7 +257,7 @@ lh7a400_bus_free( bus_t *bus )
 	free( bus );
 }
 
-static bus_t *lh7a400_bus_new( char *cmd_params[] );
+static bus_t *lh7a400_bus_new( chain_t *chain, char *cmd_params[] );
 
 const bus_driver_t lh7a400_bus = {
 	"lh7a400",
@@ -276,7 +276,7 @@ const bus_driver_t lh7a400_bus = {
 };
 
 static bus_t *
-lh7a400_bus_new( char *cmd_params[] )
+lh7a400_bus_new( chain_t *chain, char *cmd_params[] )
 {
 	bus_t *bus;
 	char buff[10];
diff --git a/jtag/src/bus/mpc5200.c b/jtag/src/bus/mpc5200.c
index 774bc907..8b97fce7 100644
--- a/jtag/src/bus/mpc5200.c
+++ b/jtag/src/bus/mpc5200.c
@@ -243,7 +243,7 @@ mpc5200_bus_free( bus_t *bus )
 }
 
 static bus_t *
-mpc5200_bus_new( char *cmd_params[] )
+mpc5200_bus_new( chain_t *chain, char *cmd_params[] )
 {
 	bus_t *bus;
 	char buff[10];
diff --git a/jtag/src/bus/mpc824x.c b/jtag/src/bus/mpc824x.c
index f4abe2cd..6cb04583 100644
--- a/jtag/src/bus/mpc824x.c
+++ b/jtag/src/bus/mpc824x.c
@@ -288,13 +288,13 @@ mpc824x_bus_write( bus_t *bus, uint32_t adr, uint32_t data )
 
 	setup_data( bus, adr, data );
 
-	chain_shift_data_registers( chain, 0 );
+	chain_shift_data_registers( CHAIN, 0 );
 
 	part_set_signal( p, nWE, 1, 0 );
-	chain_shift_data_registers( chain, 0 );
+	chain_shift_data_registers( CHAIN, 0 );
 	part_set_signal( p, nWE, 1, 1 );
 	part_set_signal( p, nRCS0, 1, 1 );
-	chain_shift_data_registers( chain, 0 );
+	chain_shift_data_registers( CHAIN, 0 );
 
 
 
@@ -357,7 +357,7 @@ mpc824x_bus_free( bus_t *bus )
 }
 
 static bus_t *
-mpc824x_bus_new( char *cmd_params[] )
+mpc824x_bus_new( chain_t *chain, char *cmd_params[] )
 {
 	bus_t *bus;
 	char buff[10];
diff --git a/jtag/src/bus/ppc405ep.c b/jtag/src/bus/ppc405ep.c
index 52d2d11e..92fd17c1 100644
--- a/jtag/src/bus/ppc405ep.c
+++ b/jtag/src/bus/ppc405ep.c
@@ -216,7 +216,7 @@ ppc405ep_bus_free( bus_t *bus )
 	free( bus );
 }
 
-static bus_t *ppc405ep_bus_new( char *cmd_params[] );
+static bus_t *ppc405ep_bus_new( chain_t *chain, char *cmd_params[] );
 
 const bus_driver_t ppc405ep_bus = {
 	"ppc405ep",
@@ -234,7 +234,7 @@ const bus_driver_t ppc405ep_bus = {
 };
 
 static bus_t *
-ppc405ep_bus_new( char *cmd_params[] )
+ppc405ep_bus_new( chain_t *chain, char *cmd_params[] )
 {
 	bus_t *bus;
 	char buff[10];
diff --git a/jtag/src/bus/ppc440gx_ebc8.c b/jtag/src/bus/ppc440gx_ebc8.c
index 7b6c65e1..953aaa21 100644
--- a/jtag/src/bus/ppc440gx_ebc8.c
+++ b/jtag/src/bus/ppc440gx_ebc8.c
@@ -214,7 +214,7 @@ ppc440gx_ebc8_bus_free( bus_t *bus )
 	free( bus );
 }
 
-static bus_t *ppc440gx_ebc8_bus_new( char *cmd_params[] );
+static bus_t *ppc440gx_ebc8_bus_new( chain_t *chain, char *cmd_params[] );
 
 const bus_driver_t ppc440gx_ebc8_bus = {
 	"ppc440gx_ebc8",
@@ -233,7 +233,7 @@ const bus_driver_t ppc440gx_ebc8_bus = {
 };
 
 static bus_t *
-ppc440gx_ebc8_bus_new( char *cmd_params[] )
+ppc440gx_ebc8_bus_new( chain_t *chain, char *cmd_params[] )
 {
 	bus_t *bus;
 	char buff[10];
diff --git a/jtag/src/bus/prototype.c b/jtag/src/bus/prototype.c
index c21a5966..cd391f16 100644
--- a/jtag/src/bus/prototype.c
+++ b/jtag/src/bus/prototype.c
@@ -253,7 +253,7 @@ prototype_bus_signal_parse( char *str, char *fmt, int *inst )
 }
 
 static bus_t *
-prototype_bus_new( char *cmd_params[] )
+prototype_bus_new( chain_t *chain, char *cmd_params[] )
 {
 	bus_t *bus;
 	signal_t *sig;
diff --git a/jtag/src/bus/pxa2x0.c b/jtag/src/bus/pxa2x0.c
index f07f4643..95d50e76 100644
--- a/jtag/src/bus/pxa2x0.c
+++ b/jtag/src/bus/pxa2x0.c
@@ -607,8 +607,8 @@ pxa2xx_bus_free( bus_t *bus )
 	free( bus );
 }
 
-static bus_t *pxa2x0_bus_new( char *cmd_params[] );
-static bus_t *pxa27x_bus_new( char *cmd_params[] );
+static bus_t *pxa2x0_bus_new( chain_t *chain, char *cmd_params[] );
+static bus_t *pxa27x_bus_new( chain_t *chain, char *cmd_params[] );
 
 const bus_driver_t pxa2x0_bus = {
 	"pxa2x0",
@@ -754,7 +754,7 @@ pxa2xx_bus_new_common(bus_t * bus)
 }
 
 static bus_t *
-pxa2x0_bus_new( char *cmd_params[] )
+pxa2x0_bus_new( chain_t *chain, char *cmd_params[] )
 {
 	bus_t *bus;
 	int failed = 0;
@@ -791,7 +791,7 @@ pxa2x0_bus_new( char *cmd_params[] )
 }
 
 static bus_t *
-pxa27x_bus_new( char *cmd_params[] )
+pxa27x_bus_new( chain_t *chain, char *cmd_params[] )
 {
 	bus_t *bus;
 	int failed = 0;
diff --git a/jtag/src/bus/s3c4510x.c b/jtag/src/bus/s3c4510x.c
index a365a8ba..27a0ab61 100644
--- a/jtag/src/bus/s3c4510x.c
+++ b/jtag/src/bus/s3c4510x.c
@@ -325,7 +325,7 @@ s3c4510_bus_free( bus_t *bus )
         free( bus );
 }
 
-static bus_t *s3c4510_bus_new( char *cmd_params[] );
+static bus_t *s3c4510_bus_new( chain_t *chain, char *cmd_params[] );
 
 const bus_driver_t s3c4510_bus = {
 	"s3c4510x",
@@ -344,7 +344,7 @@ const bus_driver_t s3c4510_bus = {
 };
 
 static bus_t *
-s3c4510_bus_new( char *cmd_params[] )
+s3c4510_bus_new( chain_t *chain, char *cmd_params[] )
 {
         bus_t *bus;
         char buff[10];
diff --git a/jtag/src/bus/sa1110.c b/jtag/src/bus/sa1110.c
index dc00ddc8..0f6f79e3 100644
--- a/jtag/src/bus/sa1110.c
+++ b/jtag/src/bus/sa1110.c
@@ -245,7 +245,7 @@ sa1110_bus_free( bus_t *bus )
 	free( bus );
 }
 
-static bus_t *sa1110_bus_new( char *cmd_params[] );
+static bus_t *sa1110_bus_new( chain_t *chain, char *cmd_params[] );
 
 const bus_driver_t sa1110_bus = {
 	"sa1110",
@@ -264,7 +264,7 @@ const bus_driver_t sa1110_bus = {
 };
 
 static bus_t *
-sa1110_bus_new( char *cmd_params[] )
+sa1110_bus_new( chain_t *chain, char *cmd_params[] )
 {
 	bus_t *bus;
 	char buff[10];
diff --git a/jtag/src/bus/sh7727.c b/jtag/src/bus/sh7727.c
index 6fd86630..7320dc1e 100644
--- a/jtag/src/bus/sh7727.c
+++ b/jtag/src/bus/sh7727.c
@@ -277,7 +277,7 @@ sh7727_bus_free( bus_t *bus )
 	free( bus );
 }
 
-static bus_t *sh7727_bus_new( char *cmd_params[] );
+static bus_t *sh7727_bus_new( chain_t *chain, char *cmd_params[] );
 
 const bus_driver_t sh7727_bus = {
 	"sh7727",
@@ -296,7 +296,7 @@ const bus_driver_t sh7727_bus = {
 };
 
 static bus_t *
-sh7727_bus_new( char *cmd_params[] )
+sh7727_bus_new( chain_t *chain, char *cmd_params[] )
 {
 	bus_t *bus;
 	char buff[10];
diff --git a/jtag/src/bus/sh7750r.c b/jtag/src/bus/sh7750r.c
index 217e801c..d87f2b12 100644
--- a/jtag/src/bus/sh7750r.c
+++ b/jtag/src/bus/sh7750r.c
@@ -259,7 +259,7 @@ sh7750r_bus_free( bus_t *bus )
 	free( bus );
 }
 
-static bus_t *sh7750r_bus_new( char *cmd_params[] );
+static bus_t *sh7750r_bus_new( chain_t *chain, char *cmd_params[] );
 
 const bus_driver_t sh7750r_bus = {
 	"sh7750r",
@@ -278,7 +278,7 @@ const bus_driver_t sh7750r_bus = {
 };
 
 static bus_t *
-sh7750r_bus_new( char *cmd_params[] )
+sh7750r_bus_new( chain_t *chain, char *cmd_params[] )
 {
 	bus_t *bus;
 	char buff[10];
diff --git a/jtag/src/bus/sh7751r.c b/jtag/src/bus/sh7751r.c
index 284e146a..6cb46e32 100644
--- a/jtag/src/bus/sh7751r.c
+++ b/jtag/src/bus/sh7751r.c
@@ -252,7 +252,7 @@ sh7751r_bus_free( bus_t *bus )
 	free( bus );
 }
 
-static bus_t *sh7751r_bus_new( char *cmd_params[] );
+static bus_t *sh7751r_bus_new( chain_t *chain, char *cmd_params[] );
 
 const bus_driver_t sh7751r_bus = {
 	"sh7751r",
@@ -271,7 +271,7 @@ const bus_driver_t sh7751r_bus = {
 };
 
 static bus_t *
-sh7751r_bus_new( char *cmd_params[] )
+sh7751r_bus_new( chain_t *chain, char *cmd_params[] )
 {
 	bus_t *bus;
 	char buff[10];
diff --git a/jtag/src/bus/sharc21065l.c b/jtag/src/bus/sharc21065l.c
index 022dcae3..65dc4d5c 100644
--- a/jtag/src/bus/sharc21065l.c
+++ b/jtag/src/bus/sharc21065l.c
@@ -258,7 +258,7 @@ static void sharc_21065L_bus_free( bus_t *bus )
 	free( bus );
 }
 
-static bus_t *sharc_21065L_bus_new( char *cmd_params[] );
+static bus_t *sharc_21065L_bus_new( chain_t *chain, char *cmd_params[] );
 
 const bus_driver_t sharc_21065L_bus = {
 	"SHARC_21065L",
@@ -276,7 +276,7 @@ const bus_driver_t sharc_21065L_bus = {
 };
 
 
-static bus_t *sharc_21065L_bus_new( char *cmd_params[] )
+static bus_t *sharc_21065L_bus_new( chain_t *chain, char *cmd_params[] )
 {
 	bus_t *bus;
 	char buff[15];
diff --git a/jtag/src/bus/slsup3.c b/jtag/src/bus/slsup3.c
index b019b317..cd3c0684 100644
--- a/jtag/src/bus/slsup3.c
+++ b/jtag/src/bus/slsup3.c
@@ -356,7 +356,7 @@ slsup3_bus_free( bus_t *bus )
 }
 
 static bus_t *
-slsup3_bus_new( char *cmd_params[] )
+slsup3_bus_new( chain_t *chain, char *cmd_params[] )
 {
 	bus_t *bus;
 	char buff[10];
diff --git a/jtag/src/bus/tx4925.c b/jtag/src/bus/tx4925.c
index 5a4cfdc6..73b8ec72 100644
--- a/jtag/src/bus/tx4925.c
+++ b/jtag/src/bus/tx4925.c
@@ -249,7 +249,7 @@ tx4925_bus_free( bus_t *bus )
 	free( bus );
 }
 
-static bus_t *tx4925_bus_new( char *cmd_params[] );
+static bus_t *tx4925_bus_new( chain_t *chain, char *cmd_params[] );
 
 const bus_driver_t tx4925_bus = {
 	"tx4925",
@@ -269,7 +269,7 @@ const bus_driver_t tx4925_bus = {
 
 
 static bus_t *
-tx4925_bus_new( char *cmd_params[] )
+tx4925_bus_new( chain_t *chain, char *cmd_params[] )
 {
 	bus_t *bus;
 	char buff[15];
diff --git a/jtag/src/bus/zefant-xs3.c b/jtag/src/bus/zefant-xs3.c
index d5b6e6f4..2f94ab6a 100644
--- a/jtag/src/bus/zefant-xs3.c
+++ b/jtag/src/bus/zefant-xs3.c
@@ -723,7 +723,7 @@ attach_sig( bus_t *bus, signal_t **sig, char *id )
 }
 
 static bus_t *
-zefant_xs3_bus_new( char *cmd_params[] )
+zefant_xs3_bus_new( chain_t *chain, char *cmd_params[] )
 {
 	bus_t *bus;
 	int failed = 0;
diff --git a/jtag/src/cmd/bit.c b/jtag/src/cmd/bit.c
index 6bcd4a77..10dd48ac 100644
--- a/jtag/src/cmd/bit.c
+++ b/jtag/src/cmd/bit.c
@@ -44,7 +44,7 @@ cmd_bit_print_params( char *params[], unsigned int parameters, char *command )
 }
 
 static int
-cmd_bit_run( char *params[] )
+cmd_bit_run( chain_t *chain, char *params[] )
 {
 	part_t *part;
 	data_register *bsr;
@@ -62,7 +62,7 @@ cmd_bit_run( char *params[] )
 		return -1;
 	}
 
-	if (!cmd_test_cable()) {
+	if (!cmd_test_cable( chain )) {
 		printf( _("%s: cable test failed for command '%s'\n"), "bit", command);
 		return 1;
 	}
diff --git a/jtag/src/cmd/bsdl.c b/jtag/src/cmd/bsdl.c
index 6349d906..32bcef31 100644
--- a/jtag/src/cmd/bsdl.c
+++ b/jtag/src/cmd/bsdl.c
@@ -32,7 +32,7 @@
 #include <cmd.h>
 
 static int
-cmd_bsdl_run( char *params[] )
+cmd_bsdl_run( chain_t *chain, char *params[] )
 {
 	int num_params, result = -1;
 
@@ -44,9 +44,9 @@ cmd_bsdl_run( char *params[] )
 			debug_save = bsdl_debug;
 			bsdl_debug = 1;
 			if (num_params == 3) {
-				result = bsdl_read_file(params[2], -1, NULL) >= 0 ? 1 : -1;
+				result = bsdl_read_file(chain, params[2], -1, NULL) >= 0 ? 1 : -1;
 			} else if (num_params == 2) {
-				bsdl_scan_files(NULL, -1);
+				bsdl_scan_files(chain, NULL, -1);
 				result = 1;
 			}
 			bsdl_debug = debug_save;
@@ -54,9 +54,9 @@ cmd_bsdl_run( char *params[] )
 
 		if (strcmp(params[1], "dump") == 0) {
 			if (num_params == 3) {
-				result = bsdl_read_file(params[2], 0, NULL) >= 0 ? 1 : -1;
+				result = bsdl_read_file(chain, params[2], 0, NULL) >= 0 ? 1 : -1;
 			} else if (num_params == 2) {
-				bsdl_scan_files(NULL, 0);
+				bsdl_scan_files(chain, NULL, 0);
 				result = 1;
 			}
 		}
diff --git a/jtag/src/cmd/bus.c b/jtag/src/cmd/bus.c
index b4cd350c..eefe6ecb 100644
--- a/jtag/src/cmd/bus.c
+++ b/jtag/src/cmd/bus.c
@@ -32,14 +32,14 @@
 #include "cmd.h"
 
 static int
-cmd_bus_run( char *params[] )
+cmd_bus_run( chain_t *chain, char *params[] )
 {
 	unsigned int n;
 
 	if (cmd_params( params ) != 2)
 		return -1;
 
-	if (!cmd_test_cable())
+	if (!cmd_test_cable( chain ))
 		return 1;
 
 	if (!chain->parts) {
diff --git a/jtag/src/cmd/cable.c b/jtag/src/cmd/cable.c
index 6ccbc295..671b961d 100644
--- a/jtag/src/cmd/cable.c
+++ b/jtag/src/cmd/cable.c
@@ -38,7 +38,7 @@
 #include "cmd.h"
 
 static int
-cmd_cable_run( char *params[] )
+cmd_cable_run( chain_t *chain, char *params[] )
 {
 	cable_t *cable;
 	int i;
diff --git a/jtag/src/cmd/cmd.c b/jtag/src/cmd/cmd.c
index 983adf92..9aa32fa6 100644
--- a/jtag/src/cmd/cmd.c
+++ b/jtag/src/cmd/cmd.c
@@ -117,7 +117,7 @@ const cmd_t *cmds[] = {
 };
 
 int
-cmd_test_cable( void )
+cmd_test_cable( chain_t *chain )
 {
 	if (chain->cable)
 		return 1;
@@ -129,7 +129,7 @@ cmd_test_cable( void )
 /* Remainder copied from libbrux/cmd/cmd.c */
 
 int
-cmd_run( char *params[] )
+cmd_run( chain_t *chain, char *params[] )
 {
 	int i;
 
@@ -138,7 +138,7 @@ cmd_run( char *params[] )
 
 	for (i = 0; cmds[i]; i++)
 		if (strcasecmp( cmds[i]->name, params[0] ) == 0) {
-			int r = cmds[i]->run( params );
+			int r = cmds[i]->run( chain, params );
 			if (r < 0)
 				printf( _("%s: syntax error!\n"), params[0] );
 			return r;
diff --git a/jtag/src/cmd/debug.c b/jtag/src/cmd/debug.c
index ad236005..662c96fe 100644
--- a/jtag/src/cmd/debug.c
+++ b/jtag/src/cmd/debug.c
@@ -35,7 +35,7 @@
 #include "cmd.h"
 
 static int
-cmd_debug_run( char *params[] )
+cmd_debug_run( chain_t *chain, char *params[] )
 {
 	unsigned int i;
 
diff --git a/jtag/src/cmd/detect.c b/jtag/src/cmd/detect.c
index af87470e..1e430e44 100644
--- a/jtag/src/cmd/detect.c
+++ b/jtag/src/cmd/detect.c
@@ -34,7 +34,7 @@
 #include "cmd.h"
 
 static int
-cmd_detect_run( char *params[] )
+cmd_detect_run( chain_t *chain, char *params[] )
 {
 	int i;
 	bus_t * abus;
@@ -42,7 +42,7 @@ cmd_detect_run( char *params[] )
 	if (cmd_params( params ) != 1)
 		return -1;
 
-	if (!cmd_test_cable())
+	if (!cmd_test_cable( chain ))
 		return 1;
 
 	buses_free();
diff --git a/jtag/src/cmd/detectflash.c b/jtag/src/cmd/detectflash.c
index f27415c5..417b32a1 100644
--- a/jtag/src/cmd/detectflash.c
+++ b/jtag/src/cmd/detectflash.c
@@ -30,7 +30,7 @@
 #include <cmd.h>
 
 static int
-cmd_detectflash_run( char *params[] )
+cmd_detectflash_run( chain_t *chain, char *params[] )
 {
 	uint32_t adr;
 
diff --git a/jtag/src/cmd/discovery.c b/jtag/src/cmd/discovery.c
index b8882508..c4e5806f 100644
--- a/jtag/src/cmd/discovery.c
+++ b/jtag/src/cmd/discovery.c
@@ -31,12 +31,12 @@
 #include "cmd.h"
 
 static int
-cmd_discovery_run( char *params[] )
+cmd_discovery_run( chain_t *chain, char *params[] )
 {
 	if (cmd_params( params ) != 1)
 		return -1;
 
-	if (!cmd_test_cable())
+	if (!cmd_test_cable( chain ))
 		return 1;
 
 	discovery( chain );
diff --git a/jtag/src/cmd/dr.c b/jtag/src/cmd/dr.c
index 89a4b243..7423631c 100644
--- a/jtag/src/cmd/dr.c
+++ b/jtag/src/cmd/dr.c
@@ -33,7 +33,7 @@
 #include "cmd.h"
 
 static int
-cmd_dr_run( char *params[] )
+cmd_dr_run( chain_t *chain, char *params[] )
 {
 	int dir = 1;
 	tap_register *r;
@@ -41,7 +41,7 @@ cmd_dr_run( char *params[] )
 	if (cmd_params( params ) < 1 || cmd_params( params ) > 2)
 		return -1;
 
-	if (!cmd_test_cable())
+	if (!cmd_test_cable( chain ))
 		return 1;
 
 	if (!chain->parts) {
diff --git a/jtag/src/cmd/endian.c b/jtag/src/cmd/endian.c
index 7d739ffc..eac3acfc 100644
--- a/jtag/src/cmd/endian.c
+++ b/jtag/src/cmd/endian.c
@@ -32,7 +32,7 @@
 #include "cmd.h"
 
 static int
-cmd_endian_run( char *params[] )
+cmd_endian_run( chain_t *chain, char *params[] )
 {
 	if (cmd_params( params ) > 2)
 		return -1;
diff --git a/jtag/src/cmd/eraseflash.c b/jtag/src/cmd/eraseflash.c
index 66a93cf5..2d4ad04b 100644
--- a/jtag/src/cmd/eraseflash.c
+++ b/jtag/src/cmd/eraseflash.c
@@ -34,14 +34,14 @@
 #include "cmd.h"
 
 static int
-cmd_eraseflash_run( char *params[] )
+cmd_eraseflash_run( chain_t *chain, char *params[] )
 {
 	uint32_t adr = 0;
 	unsigned int number = 0;
 
 	if (cmd_params( params ) != 3)
 		return -1;
-	if (!cmd_test_cable())
+	if (!cmd_test_cable( chain ))
 		return 1;
 	if (!bus) {
 		printf( _("Error: Bus driver missing.\n") );
diff --git a/jtag/src/cmd/flashmem.c b/jtag/src/cmd/flashmem.c
index d76957ea..311df528 100644
--- a/jtag/src/cmd/flashmem.c
+++ b/jtag/src/cmd/flashmem.c
@@ -34,7 +34,7 @@
 #include "cmd.h"
 
 static int
-cmd_flashmem_run( char *params[] )
+cmd_flashmem_run( chain_t *chain, char *params[] )
 {
 	int msbin;
 	uint32_t adr = 0;
diff --git a/jtag/src/cmd/frequency.c b/jtag/src/cmd/frequency.c
index af235f4d..23e9d7ee 100644
--- a/jtag/src/cmd/frequency.c
+++ b/jtag/src/cmd/frequency.c
@@ -32,7 +32,7 @@
 #include "cmd.h"
 
 static int
-cmd_frequency_run( char *params[] )
+cmd_frequency_run( chain_t *chain, char *params[] )
 {
 	unsigned int freq;
 
diff --git a/jtag/src/cmd/get.c b/jtag/src/cmd/get.c
index bc71b7fc..f94701a0 100644
--- a/jtag/src/cmd/get.c
+++ b/jtag/src/cmd/get.c
@@ -34,7 +34,7 @@
 #include "cmd.h"
 
 static int
-cmd_get_run( char *params[] )
+cmd_get_run( chain_t *chain, char *params[] )
 {
 	int data;
 	signal_t *s;
@@ -45,7 +45,7 @@ cmd_get_run( char *params[] )
 	if (strcasecmp( params[1], "signal") != 0)
 		return -1;
 
-	if (!cmd_test_cable())
+	if (!cmd_test_cable( chain ))
 		return 1;
 
 	if (!chain->parts) {
diff --git a/jtag/src/cmd/help.c b/jtag/src/cmd/help.c
index e114cea7..580cb367 100644
--- a/jtag/src/cmd/help.c
+++ b/jtag/src/cmd/help.c
@@ -30,7 +30,7 @@
 #include <cmd.h>
 
 static int
-cmd_help_run( char *params[] )
+cmd_help_run( chain_t *chain, char *params[] )
 {
 	int i;
 
diff --git a/jtag/src/cmd/include.c b/jtag/src/cmd/include.c
index b18f556a..a84b3451 100644
--- a/jtag/src/cmd/include.c
+++ b/jtag/src/cmd/include.c
@@ -34,7 +34,7 @@
 #include "bsdl.h"
 
 static int
-cmd_include_or_script_run( int is_include, char *params[] )
+cmd_include_or_script_run( chain_t *chain, int is_include, char *params[] )
 {
 	int go = 0, i, j = 1;
 	char *path;
@@ -72,10 +72,10 @@ cmd_include_or_script_run( int is_include, char *params[] )
 
 #ifdef ENABLE_BSDL
 	/* perform a test read to check for BSDL syntax */
-	if (bsdl_read_file( path, -1, NULL ) >= 0)
+	if (bsdl_read_file( chain, path, -1, NULL ) >= 0)
 	{
 		/* it seems to be a proper BSDL file, so re-read and execute */
-		go = bsdl_read_file( path, 1, NULL );
+		go = bsdl_read_file( chain, path, 1, NULL );
 
 		free( path );
 		return go >= 0 ? 1 : 0;
@@ -87,7 +87,7 @@ cmd_include_or_script_run( int is_include, char *params[] )
 	};
 
 	for(i = 0; i < j ;i++) {
-		go = jtag_parse_file( path );
+		go = jtag_parse_file( chain, path );
 
 		if (go < 0) {
 			if (go != -99)
@@ -113,9 +113,9 @@ cmd_include_or_script_help( char *cmd )
 }
 
 static int
-cmd_include_run( char *params[] )
+cmd_include_run( chain_t *chain, char *params[] )
 {
-	return cmd_include_or_script_run( 1, params );
+	return cmd_include_or_script_run( chain, 1, params );
 }
 
 static void
@@ -132,9 +132,9 @@ cmd_t cmd_include = {
 };
 
 static int
-cmd_script_run( char *params[] )
+cmd_script_run( chain_t *chain, char *params[] )
 {
-	return cmd_include_or_script_run( 0, params );
+	return cmd_include_or_script_run( chain, 0, params );
 }
 
 static void
diff --git a/jtag/src/cmd/initbus.c b/jtag/src/cmd/initbus.c
index b9ce8205..32686831 100644
--- a/jtag/src/cmd/initbus.c
+++ b/jtag/src/cmd/initbus.c
@@ -32,14 +32,14 @@
 #include "jtag.h"
 
 static int
-cmd_initbus_run( char *params[] )
+cmd_initbus_run( chain_t *chain, char *params[] )
 {
 	int i;
 
 	if (cmd_params( params ) < 2)
 		return -1;
 
-	if (!cmd_test_cable())
+	if (!cmd_test_cable( chain ))
 		return 1;
 
 	if (!chain->parts) {
@@ -54,7 +54,7 @@ cmd_initbus_run( char *params[] )
 
 	for (i = 0; bus_drivers[i] != NULL; i++) {
 		if (strcasecmp( bus_drivers[i]->name, params[1] ) == 0) {
-			bus_t *bus = bus_drivers[i]->new_bus( params );
+			bus_t *bus = bus_drivers[i]->new_bus( chain, params );
 			if (bus == NULL) {
 				printf( _("bus initialization failed!\n") );
 				return 1;
diff --git a/jtag/src/cmd/instruction.c b/jtag/src/cmd/instruction.c
index 11f573d6..fbe09129 100644
--- a/jtag/src/cmd/instruction.c
+++ b/jtag/src/cmd/instruction.c
@@ -33,11 +33,11 @@
 #include "cmd.h"
 
 static int
-cmd_instruction_run( char *params[] )
+cmd_instruction_run( chain_t *chain, char *params[] )
 {
 	part_t *part;
 
-	if (!cmd_test_cable())
+	if (!cmd_test_cable( chain ))
 		return 1;
 
 	if (!chain->parts) {
diff --git a/jtag/src/cmd/part.c b/jtag/src/cmd/part.c
index 955fbc01..82f041a4 100644
--- a/jtag/src/cmd/part.c
+++ b/jtag/src/cmd/part.c
@@ -33,7 +33,7 @@
 #include "cmd.h"
 
 static int
-cmd_part_run( char *params[] )
+cmd_part_run( chain_t *chain, char *params[] )
 {
 	unsigned int n;
 
@@ -52,7 +52,7 @@ part_t *part;
 	if (cmd_params( params ) != 2)
 		return -1;
 
-	if (!cmd_test_cable())
+	if (!cmd_test_cable( chain ))
 		return 1;
 
 	if (!chain->parts) {
diff --git a/jtag/src/cmd/peekpoke.c b/jtag/src/cmd/peekpoke.c
index 72af28d5..6560e60b 100644
--- a/jtag/src/cmd/peekpoke.c
+++ b/jtag/src/cmd/peekpoke.c
@@ -32,7 +32,7 @@
 #include "cmd.h"
 
 static int
-cmd_peek_run( char *params[] )
+cmd_peek_run( chain_t *chain, char *params[] )
 {
 	uint32_t adr, val;
 	int	pars, j = 1;
@@ -95,7 +95,7 @@ cmd_t cmd_peek = {
 };
 
 static int
-cmd_poke_run( char *params[] )
+cmd_poke_run( chain_t *chain, char *params[] )
 {
 	uint32_t adr, val;
 	bus_area_t area;
diff --git a/jtag/src/cmd/print.c b/jtag/src/cmd/print.c
index 58d55004..ea1882f7 100644
--- a/jtag/src/cmd/print.c
+++ b/jtag/src/cmd/print.c
@@ -44,7 +44,7 @@ typedef char wchar_t;
 #include "cmd.h"
 
 static int
-cmd_print_run( char *params[] )
+cmd_print_run( chain_t *chain, char *params[] )
 {
 	char format[128];
 #if HAVE_SWPRINTF
@@ -58,7 +58,7 @@ cmd_print_run( char *params[] )
 	if (cmd_params( params ) > 2)
 		return -1;
 
-	if (!cmd_test_cable())
+	if (!cmd_test_cable( chain ))
 		return 1;
 
 	if (!chain->parts) {
diff --git a/jtag/src/cmd/quit.c b/jtag/src/cmd/quit.c
index aebb0bf4..ab462128 100644
--- a/jtag/src/cmd/quit.c
+++ b/jtag/src/cmd/quit.c
@@ -29,7 +29,7 @@
 #include <cmd.h>
 
 static int
-cmd_quit_run( char *params[] )
+cmd_quit_run( chain_t *chain, char *params[] )
 {
 	if (params[1])
 		return -1;
diff --git a/jtag/src/cmd/readmem.c b/jtag/src/cmd/readmem.c
index 22398441..84df5951 100644
--- a/jtag/src/cmd/readmem.c
+++ b/jtag/src/cmd/readmem.c
@@ -32,7 +32,7 @@
 #include "cmd.h"
 
 static int
-cmd_readmem_run( char *params[] )
+cmd_readmem_run( chain_t *chain, char *params[] )
 {
 	uint32_t adr;
 	uint32_t len;
diff --git a/jtag/src/cmd/register.c b/jtag/src/cmd/register.c
index 715ea570..780542a6 100644
--- a/jtag/src/cmd/register.c
+++ b/jtag/src/cmd/register.c
@@ -33,7 +33,7 @@
 #include "cmd.h"
 
 static int
-cmd_register_run( char *params[] )
+cmd_register_run( chain_t *chain, char *params[] )
 {
 	part_t *part;
 	unsigned int len;
@@ -43,7 +43,7 @@ cmd_register_run( char *params[] )
 		return -1;
 
 
-	if (!cmd_test_cable())
+	if (!cmd_test_cable( chain ))
 		return 1;
 
 	if (!chain->parts) {
diff --git a/jtag/src/cmd/reset.c b/jtag/src/cmd/reset.c
index a54c0009..2add69b1 100644
--- a/jtag/src/cmd/reset.c
+++ b/jtag/src/cmd/reset.c
@@ -34,12 +34,12 @@
 void jtag_reset( chain_t *chain );
 
 static int
-cmd_reset_run( char *params[] )
+cmd_reset_run( chain_t *chain, char *params[] )
 {
 	if (cmd_params( params ) > 1)
 		return -1;
 
-	if (!cmd_test_cable())
+	if (!cmd_test_cable( chain ))
 		return 1;
 
 	jtag_reset( chain );
diff --git a/jtag/src/cmd/salias.c b/jtag/src/cmd/salias.c
index 6250c384..89bc0ae6 100644
--- a/jtag/src/cmd/salias.c
+++ b/jtag/src/cmd/salias.c
@@ -33,7 +33,7 @@
 #include "cmd.h"
 
 static int
-cmd_salias_run( char *params[] )
+cmd_salias_run( chain_t *chain, char *params[] )
 {
 	part_t *part;
 	signal_t *s;
@@ -42,7 +42,7 @@ cmd_salias_run( char *params[] )
 	if (cmd_params( params ) != 3)
 		return -1;
 
-	if (!cmd_test_cable())
+	if (!cmd_test_cable( chain ))
 		return 1;
 
 	if (!chain->parts) {
diff --git a/jtag/src/cmd/scan.c b/jtag/src/cmd/scan.c
index 432c93d1..21f0d4e0 100644
--- a/jtag/src/cmd/scan.c
+++ b/jtag/src/cmd/scan.c
@@ -33,7 +33,7 @@
 #include "cmd.h"
 
 static int
-cmd_scan_run( char *params[] )
+cmd_scan_run( chain_t *chain, char *params[] )
 {
 	part_t *part;
     data_register *bsr;
@@ -43,7 +43,7 @@ cmd_scan_run( char *params[] )
 	if ((i = cmd_params( params )) < 1)
 		return -1;
 
-	if (!cmd_test_cable())
+	if (!cmd_test_cable( chain ))
 		return 1;
 
 	if (!chain->parts) {
diff --git a/jtag/src/cmd/set.c b/jtag/src/cmd/set.c
index 9049a750..c7148d5b 100644
--- a/jtag/src/cmd/set.c
+++ b/jtag/src/cmd/set.c
@@ -34,7 +34,7 @@
 #include "cmd.h"
 
 static int
-cmd_set_run( char *params[] )
+cmd_set_run( chain_t *chain, char *params[] )
 {
 	int dir;
 	unsigned int data = 0;
@@ -46,7 +46,7 @@ cmd_set_run( char *params[] )
 	if (strcasecmp( params[1], "signal" ) != 0)
 		return -1;
 
-	if (!cmd_test_cable())
+	if (!cmd_test_cable( chain ))
 		return 1;
 
 	if (!chain->parts) {
diff --git a/jtag/src/cmd/shell.c b/jtag/src/cmd/shell.c
index b7f7216e..bfdad132 100644
--- a/jtag/src/cmd/shell.c
+++ b/jtag/src/cmd/shell.c
@@ -37,7 +37,7 @@
 #include "cmd.h"
 
 static int
-cmd_shell_run( char *params[] )
+cmd_shell_run( chain_t *chain, char *params[] )
 {
 	int i, len, n = cmd_params(params);
 	char *shell_cmd;
diff --git a/jtag/src/cmd/shift.c b/jtag/src/cmd/shift.c
index 3101c6e5..bc5824a7 100644
--- a/jtag/src/cmd/shift.c
+++ b/jtag/src/cmd/shift.c
@@ -33,12 +33,12 @@
 #include "cmd.h"
 
 static int
-cmd_shift_run( char *params[] )
+cmd_shift_run( chain_t *chain, char *params[] )
 {
 	if (cmd_params( params ) != 2)
 		return -1;
 
-	if (!cmd_test_cable())
+	if (!cmd_test_cable( chain ))
 		return 1;
 
 	if (strcasecmp( params[1], "ir" ) == 0) {
diff --git a/jtag/src/cmd/signal.c b/jtag/src/cmd/signal.c
index c041f0cf..ce0fa5ea 100644
--- a/jtag/src/cmd/signal.c
+++ b/jtag/src/cmd/signal.c
@@ -33,7 +33,7 @@
 #include "cmd.h"
 
 static int
-cmd_signal_run( char *params[] )
+cmd_signal_run( chain_t *chain, char *params[] )
 {
 	part_t *part;
 	signal_t *s;
@@ -43,7 +43,7 @@ cmd_signal_run( char *params[] )
 		return -1;
 
 
-	if (!cmd_test_cable())
+	if (!cmd_test_cable( chain ))
 		return 1;
 
 	if (!chain->parts) {
diff --git a/jtag/src/cmd/svf.c b/jtag/src/cmd/svf.c
index 9527ef61..7a28b1b6 100644
--- a/jtag/src/cmd/svf.c
+++ b/jtag/src/cmd/svf.c
@@ -32,7 +32,7 @@
 #include <cmd.h>
 
 static int
-cmd_svf_run( char *params[] )
+cmd_svf_run( chain_t *chain, char *params[] )
 {
 	FILE *SVF_FILE;
 	int   num_params, result = -1;
@@ -43,11 +43,11 @@ cmd_svf_run( char *params[] )
 
 			if (num_params == 3) {
 				if (strcasecmp(params[2], "stop") == 0) {
-					svf_run(SVF_FILE, 1);
+					svf_run(chain, SVF_FILE, 1);
 					result = 1;
 				}
 			} else {
-				svf_run(SVF_FILE, 0);
+				svf_run(chain, SVF_FILE, 0);
 				result = 1;
 			}
 
diff --git a/jtag/src/cmd/test.c b/jtag/src/cmd/test.c
index e75f8b77..f466546f 100644
--- a/jtag/src/cmd/test.c
+++ b/jtag/src/cmd/test.c
@@ -35,7 +35,7 @@
 #include "cmd.h"
 
 static int
-cmd_test_run( char *params[] )
+cmd_test_run( chain_t *chain, char *params[] )
 {
 	int data;
 	unsigned int i;
@@ -47,7 +47,7 @@ cmd_test_run( char *params[] )
 	if (strcasecmp( params[1], "signal") != 0)
 		return -1;
 
-	if (!cmd_test_cable())
+	if (!cmd_test_cable( chain ))
 		return 1;
 
 	if (!chain->parts) {
diff --git a/jtag/src/cmd/writemem.c b/jtag/src/cmd/writemem.c
index e39761b1..01974218 100644
--- a/jtag/src/cmd/writemem.c
+++ b/jtag/src/cmd/writemem.c
@@ -30,7 +30,7 @@
 #include "cmd.h"
 
 static int
-cmd_writemem_run( char *params[] )
+cmd_writemem_run( chain_t *chain, char *params[] )
 {
 	uint32_t adr;
 	uint32_t len;
diff --git a/jtag/src/detect.c b/jtag/src/detect.c
index 6b767b54..1284d780 100644
--- a/jtag/src/detect.c
+++ b/jtag/src/detect.c
@@ -277,7 +277,7 @@ detect_parts( chain_t *chain, char *db_path )
 		chain->active_part = ps->len - 1;
 
 #ifdef ENABLE_BSDL
-		if (bsdl_scan_files(register_get_string( did ), 1) <= 0) {
+		if (bsdl_scan_files(chain, register_get_string( did ), 1) <= 0) {
 #endif
 
 		/* find JTAG declarations for a part with id */
@@ -364,7 +364,7 @@ detect_parts( chain_t *chain, char *db_path )
 		strcpy( part->manufacturer, manufacturer );
 		strcpy( part->part, partname );
 		strcpy( part->stepping, stepping );
-		cmd_run( cmd );
+		cmd_run( chain, cmd );
 #ifdef ENABLE_BSDL
 		}
 #endif
diff --git a/jtag/src/jtag.c b/jtag/src/jtag.c
index 92f6bb9f..6678eb1f 100644
--- a/jtag/src/jtag.c
+++ b/jtag/src/jtag.c
@@ -55,7 +55,6 @@
 ssize_t getline( char **lineptr, size_t *n, FILE *stream );
 #endif
 
-chain_t *chain = NULL;
 int debug_mode = 0;
 int big_endian = 0;
 int interactive = 0;
@@ -154,7 +153,7 @@ jtag_save_history( void )
 #endif
 
 static int
-jtag_parse_line( char *line )
+jtag_parse_line( chain_t *chain, char *line )
 {
 	char *t;
 	int l;
@@ -190,14 +189,14 @@ jtag_parse_line( char *line )
 		t = get_token( NULL );
 	}
 
-	r = cmd_run( a );
+	r = cmd_run( chain, a );
 	if(debug_mode & 1)printf("Return in jtag_parse_line r=%d\n",r);
 	free( a );
 	return r;
 }
 
 
-static int jtag_readline_multiple_commands_support(char * line) /* multiple commands should be separated with '::' */
+static int jtag_readline_multiple_commands_support(chain_t *chain, char * line) /* multiple commands should be separated with '::' */
 {
   int 	r;
   char	*nextcmd = line;
@@ -216,7 +215,7 @@ static int jtag_readline_multiple_commands_support(char * line) /* multiple comm
      while (*line == ':') ++line;
   } 
   
-  r = jtag_parse_line( line );
+  r = jtag_parse_line( chain, line );
 
   chain_flush( chain );
   
@@ -226,13 +225,13 @@ static int jtag_readline_multiple_commands_support(char * line) /* multiple comm
 }
 
 static void
-jtag_readline_loop( const char *prompt )
+jtag_readline_loop( chain_t *chain, const char *prompt )
 {
 #ifdef HAVE_LIBREADLINE
 	char *line = NULL;
 
 	/* Iterate */
-	while (jtag_readline_multiple_commands_support( line )) {
+	while (jtag_readline_multiple_commands_support( chain, line )) {
 		free( line );
 
 		/* Read a line from the terminal */
@@ -267,7 +266,7 @@ jtag_readline_loop( const char *prompt )
 }
 
 static int
-jtag_parse_stream( FILE *f )
+jtag_parse_stream( chain_t *chain, FILE *f )
 {
 	int go = 1;
 	char *line = NULL;
@@ -275,7 +274,7 @@ jtag_parse_stream( FILE *f )
 
 	while (go && (getline( &line, &n, f ) != -1))
 		if ((strlen(line) > 0) && (line[0] != '#'))
-			go = jtag_parse_line(line);
+			go = jtag_parse_line(chain, line);
 
 	free(line);
 
@@ -283,7 +282,7 @@ jtag_parse_stream( FILE *f )
 }
 
 int
-jtag_parse_file( const char *filename )
+jtag_parse_file( chain_t *chain, const char *filename )
 {
 	FILE *f;
 	int go;
@@ -292,7 +291,7 @@ jtag_parse_file( const char *filename )
 	if (!f)
 		return -1;
 
-	go = jtag_parse_stream( f );
+	go = jtag_parse_stream( chain, f );
 
 	fclose(f);
 	if(debug_mode & 1)printf("File Closed gp=%d\n",go);
@@ -300,7 +299,7 @@ jtag_parse_file( const char *filename )
 }
 
 static int
-jtag_parse_rc( void )
+jtag_parse_rc( chain_t *chain )
 {
 	char *home = getenv( "HOME" );
 	char *file;
@@ -319,7 +318,7 @@ jtag_parse_rc( void )
 	strcat( file, "/" );
 	strcat( file, RCFILE );
 
-	go = jtag_parse_file( file );
+	go = jtag_parse_file( chain, file );
 
 	free( file );
 
@@ -327,7 +326,7 @@ jtag_parse_rc( void )
 }
 
 static void
-cleanup( void )
+cleanup( chain_t *chain )
 {
 	cfi_array_free( cfi_array );
 	cfi_array = NULL;
@@ -350,6 +349,7 @@ main( int argc, char *const argv[] )
 	int help = 0;
 	int version = 0;
 	int quiet = 0;
+	chain_t *chain = NULL;
 
 	if(geteuid()==0 && getuid()!=0)
 	{
@@ -470,8 +470,8 @@ main( int argc, char *const argv[] )
 				return -1;
 			}
 
-			go = jtag_parse_file( argv[i] );
-			cleanup();
+			go = jtag_parse_file( chain, argv[i] );
+			cleanup( chain );
 			if (go < 0) {
 				printf( _("Unable to open file `%s'!\n"), argv[i] );
 				break;
@@ -489,9 +489,9 @@ main( int argc, char *const argv[] )
 			return -1;
 		}
 
-		jtag_parse_stream( stdin );
+		jtag_parse_stream( chain, stdin );
 
-		cleanup();
+		cleanup( chain );
 
 		return 0;
 	}
@@ -523,7 +523,7 @@ main( int argc, char *const argv[] )
 	jtag_create_jtagdir();
 
 	/* Parse and execute the RC file */
-	go = norc ? 1 : jtag_parse_rc();
+	go = norc ? 1 : jtag_parse_rc( chain );
 
 	if (go) {
 
@@ -533,7 +533,7 @@ main( int argc, char *const argv[] )
 #endif
 
 		/* main loop */
-		jtag_readline_loop( "jtag> " );
+		jtag_readline_loop( chain, "jtag> " );
 
 #ifdef HAVE_READLINE_HISTORY
 		/* Save history */
@@ -541,7 +541,7 @@ main( int argc, char *const argv[] )
 #endif
 	}
 
-	cleanup();
+	cleanup( chain );
 
 	return 0;
 }
diff --git a/jtag/src/svf/svf.c b/jtag/src/svf/svf.c
index f36bf85f..8d8dd84d 100644
--- a/jtag/src/svf/svf.c
+++ b/jtag/src/svf/svf.c
@@ -51,7 +51,7 @@
 #include "svf.h"
 #include "svf_bison.h"
 
-int yyparse(void);
+int yyparse(chain_t *chain);
 
 
 struct sxr {
@@ -93,7 +93,7 @@ static int issued_runtest_maxtime;
  * Puts TAP controller into reset state by clocking 5 times with TMS = 1.
  */
 static void
-svf_force_reset_state(void)
+svf_force_reset_state( chain_t *chain )
 {
   chain_clock(chain, 1, 0, 5);
   tap_state_reset(chain);
@@ -113,7 +113,7 @@ svf_force_reset_state(void)
  *   state : new TAP controller state
  */
 static void
-svf_goto_state(int new_state)
+svf_goto_state( chain_t *chain, int new_state)
 {
   int current_state;
 
@@ -226,12 +226,12 @@ svf_goto_state(int new_state)
       break;
 
     default:
-      svf_force_reset_state();
+      svf_force_reset_state(chain);
       break;
   }
 
   /* continue state changes */
-  svf_goto_state(new_state);
+  svf_goto_state(chain, new_state);
 }
 
 
@@ -582,7 +582,7 @@ svf_endxr(enum generic_irdr_coding ir_dr, int state)
 
 
 /* ***************************************************************************
- * svf_frequency(freq)
+ * svf_frequency(chain, freq)
  *
  * Implements the FREQUENCY command.
  *
@@ -590,7 +590,7 @@ svf_endxr(enum generic_irdr_coding ir_dr, int state)
  *   freq : frequency in HZ
  * ***************************************************************************/
 void
-svf_frequency(double freq)
+svf_frequency(chain_t *chain, double freq)
 {
   cable_set_frequency(chain->cable, freq);
 }
@@ -643,7 +643,7 @@ static void sigalrm_handler(int signal)
  *   0 : error occured
  * ***************************************************************************/
 int
-svf_runtest(struct runtest *params)
+svf_runtest(chain_t *chain, struct runtest *params)
 {
   uint32_t run_count, frequency;
 
@@ -685,7 +685,7 @@ svf_runtest(struct runtest *params)
   }
   assert(run_count > 0);
 
-  svf_goto_state(runtest_run_state);
+  svf_goto_state(chain, runtest_run_state);
 
   /* set up the timer for max_time */
   if (params->max_time > 0.0) {
@@ -714,7 +714,7 @@ svf_runtest(struct runtest *params)
   else
     chain_clock(chain, 0, 0, run_count);
 
-  svf_goto_state(runtest_end_state);
+  svf_goto_state(chain, runtest_end_state);
 
   /* stop the timer */
   if (params->max_time > 0.0) {
@@ -748,17 +748,17 @@ svf_runtest(struct runtest *params)
  *   0 : error occured
  * ***************************************************************************/
 int
-svf_state(struct path_states *path_states, int stable_state)
+svf_state(chain_t *chain, struct path_states *path_states, int stable_state)
 {
   int i;
 
   svf_state_executed = 1;
 
   for (i = 0; i < path_states->num_states; i++)
-    svf_goto_state(svf_map_state(path_states->states[i]));
+    svf_goto_state(chain, svf_map_state(path_states->states[i]));
 
   if (stable_state)
-    svf_goto_state(svf_map_state(stable_state));
+    svf_goto_state(chain, svf_map_state(stable_state));
 
   return(1);
 }
@@ -778,7 +778,7 @@ svf_state(struct path_states *path_states, int stable_state)
  *   0 : error occured
  * ***************************************************************************/
 int
-svf_sxr(enum generic_irdr_coding ir_dr, struct ths_params *params, YYLTYPE *loc)
+svf_sxr(chain_t *chain, enum generic_irdr_coding ir_dr, struct ths_params *params, YYLTYPE *loc)
 {
   struct sxr *sxr_params;
   int len, result = 1;
@@ -883,9 +883,9 @@ svf_sxr(enum generic_irdr_coding ir_dr, struct ths_params *params, YYLTYPE *loc)
   /* shift selected instruction/register */
   switch (ir_dr) {
     case generic_ir:
-      svf_goto_state(Shift_IR);
+      svf_goto_state(chain, Shift_IR);
       chain_shift_instructions_mode(chain, 0, EXITMODE_EXIT1);
-      svf_goto_state(endir);
+      svf_goto_state(chain, endir);
 
       if (sxr_params->params.tdo)
         if (!issued_sir_tdo) {
@@ -896,12 +896,12 @@ svf_sxr(enum generic_irdr_coding ir_dr, struct ths_params *params, YYLTYPE *loc)
       break;
 
     case generic_dr:
-      svf_goto_state(Shift_DR);
+      svf_goto_state(chain, Shift_DR);
       chain_shift_data_registers_mode(chain,
                                       sxr_params->params.tdo ? 1 : 0,
                                       0,
                                       EXITMODE_EXIT1);
-      svf_goto_state(enddr);
+      svf_goto_state(chain, enddr);
 
       if (sxr_params->params.tdo)
         result = svf_compare_tdo(sxr_params->params.tdo, sxr_params->params.mask, dr->out, loc);
@@ -930,7 +930,7 @@ svf_sxr(enum generic_irdr_coding ir_dr, struct ths_params *params, YYLTYPE *loc)
  *   0 : error occured
  * ***************************************************************************/
 int
-svf_trst(int trst_mode)
+svf_trst(chain_t *chain, int trst_mode)
 {
   int  trst_cable = -1;
   char *unimplemented_mode;
@@ -1009,7 +1009,7 @@ svf_txr(enum generic_irdr_coding ir_dr, struct ths_params *params)
 
 
 /* ***************************************************************************
- * svf_run(SVF_FILE, stop_on_mismatch)
+ * svf_run(chain, SVF_FILE, stop_on_mismatch)
  *
  * Main entry point for the 'svf' command. Calls the svf parser.
  *
@@ -1027,7 +1027,7 @@ svf_txr(enum generic_irdr_coding ir_dr, struct ths_params *params)
  *   0 : error occured
  * ***************************************************************************/
 void
-svf_run(FILE *SVF_FILE, int stop_on_mismatch)
+svf_run(chain_t *chain, FILE *SVF_FILE, int stop_on_mismatch)
 {
   const struct sxr sxr_default = { {0.0, NULL, NULL, NULL, NULL},
                                    1, 1};
@@ -1053,7 +1053,7 @@ svf_run(FILE *SVF_FILE, int stop_on_mismatch)
                             "32",
                             NULL};
 
-    if (cmd_run(register_cmd) < 1)
+    if (cmd_run(chain, register_cmd) < 1)
       return;
 
     if (!(dr = part_find_data_register(part, "SDR"))) {
@@ -1079,7 +1079,7 @@ svf_run(FILE *SVF_FILE, int stop_on_mismatch)
         instruction_string[len] = '\0';
         instruction_cmd[2] = instruction_string;
 
-        result = cmd_run(instruction_cmd);
+        result = cmd_run(chain,instruction_cmd);
 
         free(instruction_string);
 
@@ -1115,7 +1115,7 @@ svf_run(FILE *SVF_FILE, int stop_on_mismatch)
   part_set_instruction(part, "SIR");
 
   yyin = SVF_FILE;
-  yyparse();
+  yyparse(chain);
 
   /* clean up */
   /* SIR */
diff --git a/jtag/src/svf/svf.h b/jtag/src/svf/svf.h
index 1538079b..d31c9cbb 100644
--- a/jtag/src/svf/svf.h
+++ b/jtag/src/svf/svf.h
@@ -25,6 +25,7 @@
 
 #include <stdint.h>
 
+#include "chain.h"
 
 #define MAX_PATH_STATES 64
 
@@ -68,10 +69,10 @@ struct runtest {
 struct YYLTYPE;
 
 void svf_endxr(enum generic_irdr_coding, int);
-void svf_frequency(double);
+void svf_frequency(chain_t *, double);
 int  svf_hxr(enum generic_irdr_coding, struct ths_params *);
-int  svf_runtest(struct runtest *);
-int  svf_state(struct path_states *, int);
-int  svf_sxr(enum generic_irdr_coding, struct ths_params *, struct YYLTYPE *);
-int  svf_trst(int);
+int  svf_runtest(chain_t *, struct runtest *);
+int  svf_state(chain_t *, struct path_states *, int);
+int  svf_sxr(chain_t *, enum generic_irdr_coding, struct ths_params *, struct YYLTYPE *);
+int  svf_trst(chain_t *, int);
 int  svf_txr(enum generic_irdr_coding, struct ths_params *);
diff --git a/jtag/src/svf/svf_bison.y b/jtag/src/svf/svf_bison.y
index 5e9ead63..cde0ec7f 100644
--- a/jtag/src/svf/svf_bison.y
+++ b/jtag/src/svf/svf_bison.y
@@ -51,11 +51,13 @@ static struct svf_parser_params parser_params = {
   {0, 0.0, 0, 0, 0, 0}
 };
 
-void yyerror(const char *);
+void yyerror(YYLTYPE *, chain_t *, const char *);
 
 static void svf_free_ths_params(struct ths_params *);
 %}
 
+%parse-param {chain_t *chain}
+
 %union {
   int    token;
   double dvalue;
@@ -115,12 +117,12 @@ svf_statement
 
     | FREQUENCY ';'
       {
-        svf_frequency(0.0);
+        svf_frequency(chain, 0.0);
       }
 
     | FREQUENCY NUMBER HZ ';'
       {
-        svf_frequency($2);
+        svf_frequency(chain, $2);
       }
 
     | HDR NUMBER ths_param_list ';'
@@ -144,7 +146,7 @@ svf_statement
     | PIOMAP '(' direction IDENTIFIER piomap_rec ')' ';'
       {
         printf("PIOMAP not implemented\n");
-        yyerror("PIOMAP");
+        yyerror(&@$, chain, "PIOMAP");
         YYERROR;
       }
 
@@ -152,7 +154,7 @@ svf_statement
       {
         free($<cvalue>2);
         printf("PIO not implemented\n");
-        yyerror("PIO");
+        yyerror(&@$, chain, "PIO");
         YYERROR;
       }
 
@@ -165,8 +167,8 @@ svf_statement
         rt->run_clk   = $3.token;
         rt->end_state = $5;
 
-        if (!svf_runtest(rt)) {
-          yyerror("RUNTEST");
+        if (!svf_runtest(chain, rt)) {
+          yyerror(&@$, chain, "RUNTEST");
           YYERROR;
         }
       }
@@ -180,8 +182,8 @@ svf_statement
         rt->run_clk   = 0;
         rt->end_state = $4;
 
-        if (!svf_runtest(rt)) {
-          yyerror("RUNTEST");
+        if (!svf_runtest(chain, rt)) {
+          yyerror(&@$, chain, "RUNTEST");
           YYERROR;
         }
       }
@@ -192,11 +194,11 @@ svf_statement
         int result;
 
         p->number = $2;
-        result = svf_sxr(generic_dr, p, &@$);
+        result = svf_sxr(chain, generic_dr, p, &@$);
         svf_free_ths_params(p);
 
         if (!result) {
-          yyerror("SDR");
+          yyerror(&@$, chain, "SDR");
           YYERROR;
         }
       }
@@ -207,19 +209,19 @@ svf_statement
         int result;
 
         p->number = $2;
-        result = svf_sxr(generic_ir, p, &@$);
+        result = svf_sxr(chain, generic_ir, p, &@$);
         svf_free_ths_params(p);
 
         if (!result) {
-          yyerror("SIR");
+          yyerror(&@$, chain, "SIR");
           YYERROR;
         }
       }
 
     | STATE path_states stable_state ';'
       {
-        if (!svf_state(&parser_params.path_states, $<token>3)) {
-          yyerror("STATE");
+        if (!svf_state(chain, &parser_params.path_states, $<token>3)) {
+          yyerror(&@$, chain, "STATE");
           YYERROR;
         }
       }
@@ -234,7 +236,7 @@ svf_statement
         svf_free_ths_params(p);
 
         if (!result) {
-          yyerror("TDR");
+          yyerror(&@$, chain, "TDR");
           YYERROR;
         }
       }
@@ -249,15 +251,15 @@ svf_statement
         svf_free_ths_params(p);
 
         if (!result) {
-          yyerror("TIR");
+          yyerror(&@$, chain, "TIR");
           YYERROR;
         }
       }
 
     | TRST trst_mode ';'
     {
-      if (!svf_trst($<token>2)) {
-        yyerror("TRST");
+      if (!svf_trst(chain, $<token>2)) {
+        yyerror(&@$, chain, "TRST");
         YYERROR;
       }
     }
@@ -413,7 +415,7 @@ direction
 
 
 void
-yyerror(const char *error_string)
+yyerror(YYLTYPE *locp, chain_t *chain, const char *error_string)
 {
   printf("Error occured for SVF command %s.\n", error_string);
 }