From 60767fa68f5c83bde937e3cab4b963b49b63b0cd Mon Sep 17 00:00:00 2001
From: Marcel Telka <marcel@telka.sk>
Date: Tue, 29 Apr 2003 21:40:29 +0000
Subject: [PATCH] 2003-04-29  Marcel Telka  <marcel@telka.sk>

	* data/MANUFACTURERS: Added new manufacturer: DEC.

	* src/jtag.c (jtag_create_jtagdir): Changed permissions for jtag directory.

	* include/part.h (part_alloc, read_part): Changed return type from `part *' to `part_t *'.
	(struct parts): Changed parts member type from `part **' to `part_t **'.
	(parts_alloc): Changed return type from `parts *' to `parts_t *'.
	* src/bus/ixp425.c (select_flash, unselect_flash, setup_address, set_data_in, setup_data):
		Changed first parameter type from `part *' to `part_t *'.
	* src/bus/pxa250.c (setup_address, set_data_in, setup_data): Ditto.
	* src/bus/sa1110.c (setup_address, set_data_in, setup_data): Ditto.

	* include/bus.h: Replaced static bus_driver_t architecture with dynamic bus_t.
		Removed direct chain_t dependency. Added `params' and `prepare' members.
	All related functions' parameter types changed.
	* src/bus/ixp425.c (bus_params_t): New structure typedef.
	(CHAIN, PART): New macros.
	(ixp425_bus_prepare, ixp425_bus_free, new_ixp425_bus): New functions.
	(ixp425_bus_driver, ixp425_bus): Renamed `ixp425_bus_driver' to `ixp425_bus' and updated
		for new bus driver architecture.
	* src/bus/pxa250.c (bus_params_t): New structure typedef.
	(CHAIN, PART): New macros.
	(pxa250_bus_prepare, pxa250_bus_free, new_pxa250_bus): New functions.
	(pxa250_bus_driver, pxa250_bus): Renamed `pxa250_bus_driver' to `pxa250_bus' and updated
		for new bus driver architecture.
	* src/bus/sa1110.c (bus_params_t): New structure typedef.
	(CHAIN, PART): New macros.
	(sa1110_bus_prepare, sa1110_bus_free, new_sa1110_bus): New functions.
	(sa1110_bus_driver, sa1110_bus): Renamed `sa1110_bus_driver' to `sa1110_bus' and updated
		for new bus driver architecture.
	* src/readmem.c (detectflash, readmem): Moved JTAG chain initialization to bus->prepare().
	* src/flash.c (flashcheck): Ditto.
	(flashmsbin, flashmem): Removed BYPASS instruction setup.
	* src/jtag.c (bus_driver, bus): Replaced `bus_driver' with `bus' global variable.
	(jtag_parse_line, main): Added `bus' deallocation.
	* src/flash.h (flash_driver_t): Changed parameter type for all function members from
		`chain_t*' to `bus_t *'.
	All function callers changed.


git-svn-id: https://urjtag.svn.sourceforge.net/svnroot/urjtag/trunk@423 b68d4a1b-bc3d-0410-92ed-d4ac073336b7
---
 jtag/ChangeLog          |  41 ++++++++++++++
 jtag/NEWS               |   2 +
 jtag/data/MANUFACTURERS |   1 +
 jtag/include/bus.h      |  43 +++++++-------
 jtag/include/part.h     |   8 +--
 jtag/src/bus/ixp425.c   | 108 +++++++++++++++++++++++++++---------
 jtag/src/bus/pxa2x0.c   | 105 ++++++++++++++++++++++++++---------
 jtag/src/bus/sa1110.c   |  94 ++++++++++++++++++++++++-------
 jtag/src/cfi.c          |  65 +++++++++++-----------
 jtag/src/flash-amd.c    |  73 ++++++++++++------------
 jtag/src/flash-intel.c  | 120 ++++++++++++++++++++--------------------
 jtag/src/flash.c        |  67 ++++++++--------------
 jtag/src/flash.h        |  15 +++--
 jtag/src/jtag.c         |  26 ++++++---
 jtag/src/jtag.h         |  11 ++--
 jtag/src/readmem.c      |  50 +++++++----------
 16 files changed, 512 insertions(+), 317 deletions(-)

diff --git a/jtag/ChangeLog b/jtag/ChangeLog
index 9bb21ff8..6a7258e2 100644
--- a/jtag/ChangeLog
+++ b/jtag/ChangeLog
@@ -1,3 +1,44 @@
+2003-04-29  Marcel Telka  <marcel@telka.sk>
+
+	* data/MANUFACTURERS: Added new manufacturer: DEC.
+
+	* src/jtag.c (jtag_create_jtagdir): Changed permissions for jtag directory.
+
+	* include/part.h (part_alloc, read_part): Changed return type from `part *' to `part_t *'.
+	(struct parts): Changed parts member type from `part **' to `part_t **'.
+	(parts_alloc): Changed return type from `parts *' to `parts_t *'.
+	* src/bus/ixp425.c (select_flash, unselect_flash, setup_address, set_data_in, setup_data):
+		Changed first parameter type from `part *' to `part_t *'.
+	* src/bus/pxa250.c (setup_address, set_data_in, setup_data): Ditto.
+	* src/bus/sa1110.c (setup_address, set_data_in, setup_data): Ditto.
+
+	* include/bus.h: Replaced static bus_driver_t architecture with dynamic bus_t.
+		Removed direct chain_t dependency. Added `params' and `prepare' members.
+	All related functions' parameter types changed.
+	* src/bus/ixp425.c (bus_params_t): New structure typedef.
+	(CHAIN, PART): New macros.
+	(ixp425_bus_prepare, ixp425_bus_free, new_ixp425_bus): New functions.
+	(ixp425_bus_driver, ixp425_bus): Renamed `ixp425_bus_driver' to `ixp425_bus' and updated
+		for new bus driver architecture.
+	* src/bus/pxa250.c (bus_params_t): New structure typedef.
+	(CHAIN, PART): New macros.
+	(pxa250_bus_prepare, pxa250_bus_free, new_pxa250_bus): New functions.
+	(pxa250_bus_driver, pxa250_bus): Renamed `pxa250_bus_driver' to `pxa250_bus' and updated
+		for new bus driver architecture.
+	* src/bus/sa1110.c (bus_params_t): New structure typedef.
+	(CHAIN, PART): New macros.
+	(sa1110_bus_prepare, sa1110_bus_free, new_sa1110_bus): New functions.
+	(sa1110_bus_driver, sa1110_bus): Renamed `sa1110_bus_driver' to `sa1110_bus' and updated
+		for new bus driver architecture.
+	* src/readmem.c (detectflash, readmem): Moved JTAG chain initialization to bus->prepare().
+	* src/flash.c (flashcheck): Ditto.
+	(flashmsbin, flashmem): Removed BYPASS instruction setup.
+	* src/jtag.c (bus_driver, bus): Replaced `bus_driver' with `bus' global variable.
+	(jtag_parse_line, main): Added `bus' deallocation.
+	* src/flash.h (flash_driver_t): Changed parameter type for all function members from
+		`chain_t*' to `bus_t *'.
+	All function callers changed.
+
 2003-04-04  Marcel Telka  <marcel@telka.sk>
 
 	Version 0.3.2 released.
diff --git a/jtag/NEWS b/jtag/NEWS
index 237d733d..885074d3 100644
--- a/jtag/NEWS
+++ b/jtag/NEWS
@@ -1,5 +1,7 @@
 $Id$
 
+	* Added new manufacturer: DEC.
+
 jtag-0.3.2 (2003-04-04):
 
 	* Added driver for Keith & Koep JTAG Cable.
diff --git a/jtag/data/MANUFACTURERS b/jtag/data/MANUFACTURERS
index 150aa493..25efcea7 100644
--- a/jtag/data/MANUFACTURERS
+++ b/jtag/data/MANUFACTURERS
@@ -32,5 +32,6 @@
 00000010101	xilinx		Xilinx	# Philips Semi. (Signetics)
 00000011111	atmel		Atmel
 00000110100	cypress		Cypress
+00000110101	dec		DEC
 00001001001	xilinx		Xilinx
 00101010000	broadcom	Broadcom
diff --git a/jtag/include/bus.h b/jtag/include/bus.h
index f40dd162..0f2e2053 100644
--- a/jtag/include/bus.h
+++ b/jtag/include/bus.h
@@ -27,28 +27,33 @@
 #define	BUS_H
 
 #include <stdint.h>
-#include "part.h"
 #include "chain.h"
 
-typedef struct {
-	int (*bus_width)( chain_t * );
-	void (*bus_read_start)( chain_t *, uint32_t );
-	uint32_t (*bus_read_next)( chain_t *, uint32_t );
-	uint32_t (*bus_read_end)( chain_t * );
-	uint32_t (*bus_read)( chain_t *, uint32_t );
-	void (*bus_write)( chain_t *, uint32_t, uint32_t );
-} bus_driver_t;
+typedef struct bus bus_t;
 
-extern bus_driver_t *bus_driver;
-#define	bus_width	bus_driver->bus_width
-#define	bus_read_start	bus_driver->bus_read_start
-#define	bus_read_next	bus_driver->bus_read_next
-#define	bus_read_end	bus_driver->bus_read_end
-#define	bus_read	bus_driver->bus_read
-#define	bus_write	bus_driver->bus_write
+struct bus {
+	void *params;
+	void (*prepare)( bus_t *bus );
+	int (*width)( bus_t *bus );
+	void (*read_start)( bus_t *bus, uint32_t adr );
+	uint32_t (*read_next)( bus_t *bus, uint32_t adr );
+	uint32_t (*read_end)( bus_t *bus );
+	uint32_t (*read)( bus_t *bus, uint32_t adr );
+	void (*write)( bus_t *bus, uint32_t adr, uint32_t data );
+	void (*free)( bus_t *bus );
+};
 
-extern bus_driver_t sa1110_bus_driver;
-extern bus_driver_t pxa250_bus_driver;
-extern bus_driver_t ixp425_bus_driver;
+#define	bus_prepare(bus)	bus->prepare(bus)
+#define	bus_width(bus)		bus->width(bus)
+#define	bus_read_start(bus,adr)	bus->read_start(bus,adr)
+#define	bus_read_next(bus,adr)	bus->read_next(bus,adr)
+#define	bus_read_end(bus)	bus->read_end(bus)
+#define	bus_read(bus,adr)	bus->read(bus,adr)
+#define	bus_write(bus,adr,data)	bus->write(bus,adr,data)
+#define	bus_free(bus)		bus->free(bus)
+
+bus_t *new_sa1110_bus( chain_t *chain, int pn );
+bus_t *new_pxa250_bus( chain_t *chain, int pn );
+bus_t *new_ixp425_bus( chain_t *chain, int pn );
 
 #endif /* BUS_H */
diff --git a/jtag/include/part.h b/jtag/include/part.h
index 86523187..3833744c 100644
--- a/jtag/include/part.h
+++ b/jtag/include/part.h
@@ -52,9 +52,9 @@ struct part {
 	bsbit **bsbits;
 };
 
-part *part_alloc( void );
+part_t *part_alloc( void );
 void part_free( part_t *p );
-part *read_part( FILE *f, tap_register_t *idr );
+part_t *read_part( FILE *f, tap_register_t *idr );
 instruction *part_find_instruction( part_t *p, const char *iname );
 data_register *part_find_data_register( part_t *p, const char *drname );
 void part_set_instruction( part_t *p, const char *iname );
@@ -66,10 +66,10 @@ typedef struct parts parts_t;
 
 struct parts {
 	int len;
-	part **parts;
+	part_t **parts;
 };
 
-parts *parts_alloc( void );
+parts_t *parts_alloc( void );
 void parts_free( parts_t *ps );
 int parts_add_part( parts_t *ps, part_t *p );
 void parts_set_instruction( parts_t *ps, const char *iname );
diff --git a/jtag/src/bus/ixp425.c b/jtag/src/bus/ixp425.c
index 4a1e5196..38f223d3 100644
--- a/jtag/src/bus/ixp425.c
+++ b/jtag/src/bus/ixp425.c
@@ -22,16 +22,24 @@
  *
  */
 
+#include <stdlib.h>
 #include <stdint.h>
+#include <string.h>
 
 #include "part.h"
 #include "bus.h"
 #include "chain.h"
 
-/* IXP425 must be at position 0 in JTAG chain */
+typedef struct {
+	chain_t *chain;
+	part_t *part;
+} bus_params_t;
+
+#define	CHAIN	((bus_params_t *) bus->params)->chain
+#define	PART	((bus_params_t *) bus->params)->part
 
 static void 
-select_flash( part *p) 
+select_flash( part_t *p) 
 {
 	part_set_signal( p, "EX_CS[0]", 1, 0 );
 	part_set_signal( p, "EX_CS[1]", 1, 1 );
@@ -44,7 +52,7 @@ select_flash( part *p)
 }
 
 static void 
-unselect_flash( part *p) 
+unselect_flash( part_t *p) 
 {
 	part_set_signal( p, "EX_CS[0]", 1, 1 );
 	part_set_signal( p, "EX_CS[1]", 1, 1 );
@@ -57,7 +65,7 @@ unselect_flash( part *p)
 }
 
 static void
-setup_address( part *p, uint32_t a )
+setup_address( part_t *p, uint32_t a )
 {
 	int i;
 	char buff[15];
@@ -69,7 +77,7 @@ setup_address( part *p, uint32_t a )
 }
 
 static void
-set_data_in( part *p )
+set_data_in( part_t *p )
 {
 	int i;
 	char buff[15];
@@ -81,7 +89,7 @@ set_data_in( part *p )
 }
 
 static void
-setup_data( part *p, uint32_t d )
+setup_data( part_t *p, uint32_t d )
 {
 	int i;
 	char buff[15];
@@ -92,10 +100,18 @@ setup_data( part *p, uint32_t d )
 	}
 }
 
-void
-ixp425_bus_read_start( chain_t *chain, uint32_t adr )
+static void
+ixp425_bus_prepare( bus_t *bus )
+{
+	part_set_instruction( PART, "EXTEST" );
+	chain_shift_instructions( CHAIN );
+}
+
+static void
+ixp425_bus_read_start( bus_t *bus, uint32_t adr )
 {
-	part_t *p = chain->parts->parts[0];
+	part_t *p = PART;
+	chain_t *chain = CHAIN;
 
 	select_flash( p );
 	part_set_signal( p, "EX_RD", 1, 0 );
@@ -107,10 +123,11 @@ ixp425_bus_read_start( chain_t *chain, uint32_t adr )
 	chain_shift_data_registers( chain );
 }
 
-uint32_t
-ixp425_bus_read_next( chain_t *chain, uint32_t adr )
+static uint32_t
+ixp425_bus_read_next( bus_t *bus, uint32_t adr )
 {
-	part_t *p = chain->parts->parts[0];
+	part_t *p = PART;
+	chain_t *chain = CHAIN;
 
 	setup_address( p, adr );
 	chain_shift_data_registers( chain );
@@ -129,10 +146,11 @@ ixp425_bus_read_next( chain_t *chain, uint32_t adr )
 	}
 }
 
-uint32_t
-ixp425_bus_read_end( chain_t *chain )
+static uint32_t
+ixp425_bus_read_end( bus_t *bus )
 {
-	part_t *p = chain->parts->parts[0];
+	part_t *p = PART;
+	chain_t *chain = CHAIN;
 
 	unselect_flash( p );
 	part_set_signal( p, "EX_RD", 1, 1 );
@@ -154,17 +172,18 @@ ixp425_bus_read_end( chain_t *chain )
 	}
 }
 
-uint32_t
-ixp425_bus_read( chain_t *chain, uint32_t adr )
+static uint32_t
+ixp425_bus_read( bus_t *bus, uint32_t adr )
 {
-	ixp425_bus_read_start( chain, adr );
-	return ixp425_bus_read_end( chain );
+	ixp425_bus_read_start( bus, adr );
+	return ixp425_bus_read_end( bus );
 }
 
-void
-ixp425_bus_write( chain_t *chain, uint32_t adr, uint32_t data )
+static void
+ixp425_bus_write( bus_t *bus, uint32_t adr, uint32_t data )
 {
-	part_t *p = chain->parts->parts[0];
+	part_t *p = PART;
+	chain_t *chain = CHAIN;
 
 	select_flash( p );
 	part_set_signal( p, "EX_RD", 1, 1 );
@@ -181,17 +200,54 @@ ixp425_bus_write( chain_t *chain, uint32_t adr, uint32_t data )
 	chain_shift_data_registers( chain );
 }
 
-int
-ixp425_bus_width( chain_t *chain )
+static int
+ixp425_bus_width( bus_t *bus )
 {
 	return 16;
 }
 
-bus_driver_t ixp425_bus_driver = {
+static void
+ixp425_bus_free( bus_t *bus )
+{
+	free( bus->params );
+	free( bus );
+}
+
+
+static const bus_t ixp425_bus = {
+	NULL,
+	ixp425_bus_prepare,
 	ixp425_bus_width,
 	ixp425_bus_read_start,
 	ixp425_bus_read_next,
 	ixp425_bus_read_end,
 	ixp425_bus_read,
-	ixp425_bus_write
+	ixp425_bus_write,
+	ixp425_bus_free
 };
+
+bus_t *
+new_ixp425_bus( chain_t *chain, int pn )
+{
+	bus_t *bus;
+
+	if (!chain || !chain->parts || chain->parts->len <= pn || pn < 0)
+		return NULL;
+
+	bus = malloc( sizeof (bus_t) );
+	if (!bus)
+		return NULL;
+
+	memcpy( bus, &ixp425_bus, sizeof (bus_t) );
+
+	bus->params = malloc( sizeof (bus_params_t) );
+	if (!bus->params) {
+		free( bus );
+		return NULL;
+	}
+
+	CHAIN = chain;
+	PART = chain->parts->parts[pn];
+
+	return bus;
+}
diff --git a/jtag/src/bus/pxa2x0.c b/jtag/src/bus/pxa2x0.c
index 1aaaab2e..a8fd2590 100644
--- a/jtag/src/bus/pxa2x0.c
+++ b/jtag/src/bus/pxa2x0.c
@@ -26,15 +26,23 @@
  *
  */
 
+#include <stdlib.h>
 #include <stdint.h>
+#include <string.h>
 
 #include "part.h"
 #include "bus.h"
 
-/* PXA250 must be at position 0 in JTAG chain */
+typedef struct {
+	chain_t *chain;
+	part_t *part;
+} bus_params_t;
+
+#define	CHAIN	((bus_params_t *) bus->params)->chain
+#define	PART	((bus_params_t *) bus->params)->part
 
 static void
-setup_address( part *p, uint32_t a )
+setup_address( part_t *p, uint32_t a )
 {
 	int i;
 	char buff[10];
@@ -46,7 +54,7 @@ setup_address( part *p, uint32_t a )
 }
 
 static void
-set_data_in( part *p )
+set_data_in( part_t *p )
 {
 	int i;
 	char buff[10];
@@ -58,7 +66,7 @@ set_data_in( part *p )
 }
 
 static void
-setup_data( part *p, uint32_t d )
+setup_data( part_t *p, uint32_t d )
 {
 	int i;
 	char buff[10];
@@ -69,10 +77,18 @@ setup_data( part *p, uint32_t d )
 	}
 }
 
-void
-pxa250_bus_read_start( chain_t *chain, uint32_t adr )
+static void
+pxa250_bus_prepare( bus_t *bus )
+{       
+	part_set_instruction( PART, "EXTEST" );
+	chain_shift_instructions( CHAIN );
+}
+
+static void
+pxa250_bus_read_start( bus_t *bus, uint32_t adr )
 {
-	part_t *p = chain->parts->parts[0];
+	chain_t *chain = CHAIN;
+	part_t *p = PART;
 
 	/* see Figure 6-13 in [1] */
 	part_set_signal( p, "nCS[0]", 1, 0 );
@@ -91,10 +107,11 @@ pxa250_bus_read_start( chain_t *chain, uint32_t adr )
 	chain_shift_data_registers( chain );
 }
 
-uint32_t
-pxa250_bus_read_next( chain_t *chain, uint32_t adr )
+static uint32_t
+pxa250_bus_read_next( bus_t *bus, uint32_t adr )
 {
-	part_t *p = chain->parts->parts[0];
+	part_t *p = PART;
+	chain_t *chain = CHAIN;
 
 	/* see Figure 6-13 in [1] */
 	setup_address( p, adr );
@@ -114,10 +131,11 @@ pxa250_bus_read_next( chain_t *chain, uint32_t adr )
 	}
 }
 
-uint32_t
-pxa250_bus_read_end( chain_t *chain )
+static uint32_t
+pxa250_bus_read_end( bus_t *bus )
 {
-	part_t *p = chain->parts->parts[0];
+	part_t *p = PART;
+	chain_t *chain = CHAIN;
 
 	/* see Figure 6-13 in [1] */
 	part_set_signal( p, "nCS[0]", 1, 1 );
@@ -140,18 +158,19 @@ pxa250_bus_read_end( chain_t *chain )
 	}
 }
 
-uint32_t
-pxa250_bus_read( chain_t *chain, uint32_t adr )
+static uint32_t
+pxa250_bus_read( bus_t *bus, uint32_t adr )
 {
-	pxa250_bus_read_start( chain, adr );
-	return pxa250_bus_read_end( chain );
+	pxa250_bus_read_start( bus, adr );
+	return pxa250_bus_read_end( bus );
 }
 
-void
-pxa250_bus_write( chain_t *chain, uint32_t adr, uint32_t data )
+static void
+pxa250_bus_write( bus_t *bus, uint32_t adr, uint32_t data )
 {
 	/* see Figure 6-17 in [1] */
-	part_t *p = chain->parts->parts[0];
+	part_t *p = PART;
+	chain_t *chain = CHAIN;
 
 	part_set_signal( p, "nCS[0]", 1, 0 );
 	part_set_signal( p, "DQM[0]", 1, 0 );
@@ -174,10 +193,10 @@ pxa250_bus_write( chain_t *chain, uint32_t adr, uint32_t data )
 	chain_shift_data_registers( chain );
 }
 
-int
-pxa250_bus_width( chain_t *chain )
+static int
+pxa250_bus_width( bus_t *bus )
 {
-	part_t *p = chain->parts->parts[0];
+	part_t *p = PART;
 	uint8_t boot_sel = (part_get_signal( p, "BOOT_SEL[2]" ) << 2)
 			| (part_get_signal( p, "BOOT_SEL[1]" ) << 1)
 			| part_get_signal( p, "BOOT_SEL[0]" );
@@ -204,11 +223,47 @@ pxa250_bus_width( chain_t *chain )
 	}
 }
 
-bus_driver_t pxa250_bus_driver = {
+static void
+pxa250_bus_free( bus_t *bus )
+{
+	free( bus->params );
+	free( bus );
+}
+
+static const bus_t pxa250_bus = {
+	NULL,
+	pxa250_bus_prepare,
 	pxa250_bus_width,
 	pxa250_bus_read_start,
 	pxa250_bus_read_next,
 	pxa250_bus_read_end,
 	pxa250_bus_read,
-	pxa250_bus_write
+	pxa250_bus_write,
+	pxa250_bus_free
 };
+
+bus_t *
+new_pxa250_bus( chain_t *chain, int pn )
+{
+	bus_t *bus;
+
+	if (!chain || !chain->parts || chain->parts->len <= pn || pn < 0)
+		return NULL;
+	
+	bus = malloc( sizeof (bus_t) );
+	if (!bus)
+		return NULL;
+
+	memcpy( bus, &pxa250_bus, sizeof (bus_t) );
+
+	bus->params = malloc( sizeof (bus_params_t) );
+	if (!bus->params) {
+		free( bus );
+		return NULL;
+	}
+
+	CHAIN = chain;
+	PART = chain->parts->parts[pn];
+
+	return bus;
+}
diff --git a/jtag/src/bus/sa1110.c b/jtag/src/bus/sa1110.c
index 738bfb5b..4106b1c2 100644
--- a/jtag/src/bus/sa1110.c
+++ b/jtag/src/bus/sa1110.c
@@ -26,16 +26,24 @@
  *
  */
 
+#include <stdlib.h>
 #include <stdint.h>
+#include <string.h>
 
 #include "part.h"
 #include "bus.h"
 #include "chain.h"
 
-/* SA1110 must be at position 0 in JTAG chain */
+typedef struct {
+	chain_t *chain;
+	part_t *part;
+} bus_params_t;
+
+#define	CHAIN	((bus_params_t *) bus->params)->chain
+#define	PART	((bus_params_t *) bus->params)->part
 
 static void
-setup_address( part *p, uint32_t a )
+setup_address( part_t *p, uint32_t a )
 {
 	int i;
 	char buff[10];
@@ -47,7 +55,7 @@ setup_address( part *p, uint32_t a )
 }
 
 static void
-set_data_in( part *p )
+set_data_in( part_t *p )
 {
 	int i;
 	char buff[10];
@@ -59,7 +67,7 @@ set_data_in( part *p )
 }
 
 static void
-setup_data( part *p, uint32_t d )
+setup_data( part_t *p, uint32_t d )
 {
 	int i;
 	char buff[10];
@@ -71,10 +79,18 @@ setup_data( part *p, uint32_t d )
 }
 
 static void
-sa1110_bus_read_start( chain_t *chain, uint32_t adr )
+sa1110_bus_prepare( bus_t *bus )
+{       
+	part_set_instruction( PART, "EXTEST" );
+	chain_shift_instructions( CHAIN );
+}
+
+static void
+sa1110_bus_read_start( bus_t *bus, uint32_t adr )
 {
 	/* see Figure 10-12 in [1] */
-	part_t *p = chain->parts->parts[0];
+	part_t *p = PART;
+	chain_t *chain = CHAIN;
 
 	part_set_signal( p, "nCS0", 1, (adr >> 27) != 0 );
 	part_set_signal( p, "nCS1", 1, (adr >> 27) != 1 );
@@ -93,10 +109,11 @@ sa1110_bus_read_start( chain_t *chain, uint32_t adr )
 }
 
 static uint32_t
-sa1110_bus_read_next( chain_t *chain, uint32_t adr )
+sa1110_bus_read_next( bus_t *bus, uint32_t adr )
 {
 	/* see Figure 10-12 in [1] */
-	part_t *p = chain->parts->parts[0];
+	part_t *p = PART;
+	chain_t *chain = CHAIN;
 
 	setup_address( p, adr );
 	chain_shift_data_registers( chain );
@@ -116,10 +133,11 @@ sa1110_bus_read_next( chain_t *chain, uint32_t adr )
 }
 
 static uint32_t
-sa1110_bus_read_end( chain_t *chain )
+sa1110_bus_read_end( bus_t *bus )
 {
 	/* see Figure 10-12 in [1] */
-	part_t *p = chain->parts->parts[0];
+	part_t *p = PART;
+	chain_t *chain = CHAIN;
 
 	part_set_signal( p, "nCS0", 1, 1 );
 	part_set_signal( p, "nCS1", 1, 1 );
@@ -145,17 +163,18 @@ sa1110_bus_read_end( chain_t *chain )
 }
 
 static uint32_t
-sa1110_bus_read( chain_t *chain, uint32_t adr )
+sa1110_bus_read( bus_t *bus, uint32_t adr )
 {
-	sa1110_bus_read_start( chain, adr );
-	return sa1110_bus_read_end( chain );
+	sa1110_bus_read_start( bus, adr );
+	return sa1110_bus_read_end( bus );
 }
 
 static void
-sa1110_bus_write( chain_t *chain, uint32_t adr, uint32_t data )
+sa1110_bus_write( bus_t *bus, uint32_t adr, uint32_t data )
 {
 	/* see Figure 10-16 in [1] */
-	part_t *p = chain->parts->parts[0];
+	part_t *p = PART;
+	chain_t *chain = CHAIN;
 
 	part_set_signal( p, "nCS0", 1, (adr >> 27) != 0 );
 	part_set_signal( p, "nCS1", 1, (adr >> 27) != 1 );
@@ -185,9 +204,9 @@ sa1110_bus_write( chain_t *chain, uint32_t adr, uint32_t data )
 }
 
 static int
-sa1110_bus_width( chain_t *chain )
+sa1110_bus_width( bus_t *bus )
 {
-	if (part_get_signal( chain->parts->parts[0], "ROM_SEL" )) {
+	if (part_get_signal( PART, "ROM_SEL" )) {
 		printf( "ROM_SEL: 32 bits\n" );
 		return 32;
 	} else {
@@ -196,11 +215,48 @@ sa1110_bus_width( chain_t *chain )
 	}
 }
 
-bus_driver_t sa1110_bus_driver = {
+static void
+sa1110_bus_free( bus_t *bus )
+{
+	free( bus->params );
+	free( bus );
+}
+
+static const bus_t sa1110_bus = {
+	NULL,
+	sa1110_bus_prepare,
 	sa1110_bus_width,
 	sa1110_bus_read_start,
 	sa1110_bus_read_next,
 	sa1110_bus_read_end,
 	sa1110_bus_read,
-	sa1110_bus_write
+	sa1110_bus_write,
+	sa1110_bus_free
 };
+
+bus_t *
+new_sa1110_bus( chain_t *chain, int pn )
+{
+	bus_t *bus;
+
+	if (!chain || !chain->parts || chain->parts->len <= pn || pn < 0)
+		return NULL;
+
+	bus = malloc( sizeof (bus_t) );
+	if (!bus)
+		return NULL;
+
+	memcpy( bus, &sa1110_bus, sizeof (bus_t) );
+
+	bus->params = malloc( sizeof (bus_params_t) );
+	if (!bus->params) {
+		free( bus );
+		return NULL;
+	}
+
+	CHAIN = chain;
+	PART = chain->parts->parts[pn];
+
+	return bus;
+}
+
diff --git a/jtag/src/cfi.c b/jtag/src/cfi.c
index 36a8fa35..42edb1c3 100644
--- a/jtag/src/cfi.c
+++ b/jtag/src/cfi.c
@@ -34,42 +34,41 @@
 
 #include "jtag.h"
 #include "bus.h"
-#include "chain.h"
 
 /* function to cover 2x16 and 1x16 modes */
-#define BW16(x) ( (bus_width(chain) == 16) ? x : ( (x<<16) | x ) )
+#define BW16(x) ( (bus_width(bus) == 16) ? x : ( (x<<16) | x ) )
 
 static uint16_t
-read2( chain_t *chain, uint32_t adr, int o )
+read2( bus_t *bus, uint32_t adr, int o )
 {
 	uint16_t r;
 
-	bus_read_start( chain, adr << o );
-	r = bus_read_next( chain, (adr + 1) << o );
-	return ((bus_read_end( chain ) & 0xFF) << 8) | (r & 0xFF);
+	bus_read_start( bus, adr << o );
+	r = bus_read_next( bus, (adr + 1) << o );
+	return ((bus_read_end( bus ) & 0xFF) << 8) | (r & 0xFF);
 }
 
 cfi_query_structure_t *
-detect_cfi( chain_t *chain )
+detect_cfi( bus_t *bus )
 {
 	cfi_query_structure_t *cfi;
 	int o = 2;
 	uint32_t tmp;
 
-	if (bus_width( chain ) == 16)
+	if (bus_width( bus ) == 16)
 		o = 1;
 
 	/* detect CFI capable devices - see Table 1 in [1] */
-	bus_write( chain, CFI_CMD_QUERY_OFFSET << o, BW16(CFI_CMD_QUERY) );
-	if (bus_read( chain, CFI_QUERY_ID_OFFSET << o ) != BW16('Q')) {
+	bus_write( bus, CFI_CMD_QUERY_OFFSET << o, BW16(CFI_CMD_QUERY) );
+	if (bus_read( bus, CFI_QUERY_ID_OFFSET << o ) != BW16('Q')) {
 		printf( "No CFI device detected (Q)!\n" );
 		return NULL;
 	}
-	if (bus_read( chain, (CFI_QUERY_ID_OFFSET + 1) << o ) != BW16('R')) {
+	if (bus_read( bus, (CFI_QUERY_ID_OFFSET + 1) << o ) != BW16('R')) {
 		printf( "No CFI device detected (R)!\n" );
 		return NULL;
 	}
-	if (bus_read( chain, (CFI_QUERY_ID_OFFSET + 2) << o ) != BW16('Y')) {
+	if (bus_read( bus, (CFI_QUERY_ID_OFFSET + 2) << o ) != BW16('Y')) {
 		printf( "No CFI device detected (Y)!\n" );
 		return NULL;
 	}
@@ -83,60 +82,60 @@ detect_cfi( chain_t *chain )
 	/* TODO: Low chip only (bits 15:0) */
 
 	/* Identification string - see Table 6 in [1] */
-	cfi->identification_string.pri_id_code = read2( chain, PRI_VENDOR_ID_OFFSET, o );
+	cfi->identification_string.pri_id_code = read2( bus, PRI_VENDOR_ID_OFFSET, o );
 	cfi->identification_string.pri_vendor_tbl = NULL;
-	cfi->identification_string.alt_id_code = read2( chain, ALT_VENDOR_ID_OFFSET, o );
+	cfi->identification_string.alt_id_code = read2( bus, ALT_VENDOR_ID_OFFSET, o );
 	cfi->identification_string.alt_vendor_tbl = NULL;
 
 	/* System interface information - see Table 7 in [1] */
-	tmp = bus_read( chain, VCC_MIN_WEV_OFFSET << o );
+	tmp = bus_read( bus, VCC_MIN_WEV_OFFSET << o );
 	cfi->system_interface_info.vcc_min_wev = ((tmp >> 4) & 0xF) * 1000 + (tmp & 0xF) * 100;
-	tmp = bus_read( chain, VCC_MAX_WEV_OFFSET << o );
+	tmp = bus_read( bus, VCC_MAX_WEV_OFFSET << o );
 	cfi->system_interface_info.vcc_max_wev = ((tmp >> 4) & 0xF) * 1000 + (tmp & 0xF) * 100;
-	tmp = bus_read( chain, VPP_MIN_WEV_OFFSET << o );
+	tmp = bus_read( bus, VPP_MIN_WEV_OFFSET << o );
 	cfi->system_interface_info.vpp_min_wev = ((tmp >> 4) & 0xF) * 1000 + (tmp & 0xF) * 100;
-	tmp = bus_read( chain, VPP_MAX_WEV_OFFSET << o );
+	tmp = bus_read( bus, VPP_MAX_WEV_OFFSET << o );
 	cfi->system_interface_info.vpp_max_wev = ((tmp >> 4) & 0xF) * 1000 + (tmp & 0xF) * 100;
 
 	/* TODO: Add out of range checks for timeouts */
-	tmp = bus_read( chain, TYP_SINGLE_WRITE_TIMEOUT_OFFSET << o ) & 0xFF;
+	tmp = bus_read( bus, TYP_SINGLE_WRITE_TIMEOUT_OFFSET << o ) & 0xFF;
 	cfi->system_interface_info.typ_single_write_timeout = tmp ? (1 << tmp) : 0;
 
-	tmp = bus_read( chain, TYP_BUFFER_WRITE_TIMEOUT_OFFSET << o ) & 0xFF;
+	tmp = bus_read( bus, TYP_BUFFER_WRITE_TIMEOUT_OFFSET << o ) & 0xFF;
 	cfi->system_interface_info.typ_buffer_write_timeout = tmp ? (1 << tmp) : 0;
 
-	tmp = bus_read( chain, TYP_BLOCK_ERASE_TIMEOUT_OFFSET << o ) & 0xFF;
+	tmp = bus_read( bus, TYP_BLOCK_ERASE_TIMEOUT_OFFSET << o ) & 0xFF;
 	cfi->system_interface_info.typ_block_erase_timeout = tmp ? (1 << tmp) : 0;
 
-	tmp = bus_read( chain, TYP_CHIP_ERASE_TIMEOUT_OFFSET << o ) & 0xFF;
+	tmp = bus_read( bus, TYP_CHIP_ERASE_TIMEOUT_OFFSET << o ) & 0xFF;
 	cfi->system_interface_info.typ_chip_erase_timeout = tmp ? (1 << tmp) : 0;
 
-	tmp = bus_read( chain, MAX_SINGLE_WRITE_TIMEOUT_OFFSET << o ) & 0xFF;
+	tmp = bus_read( bus, MAX_SINGLE_WRITE_TIMEOUT_OFFSET << o ) & 0xFF;
 	cfi->system_interface_info.max_single_write_timeout =
 			(tmp ? (1 << tmp) : 0) * cfi->system_interface_info.typ_single_write_timeout;
 
-	tmp = bus_read( chain, MAX_BUFFER_WRITE_TIMEOUT_OFFSET << o ) & 0xFF;
+	tmp = bus_read( bus, MAX_BUFFER_WRITE_TIMEOUT_OFFSET << o ) & 0xFF;
 	cfi->system_interface_info.max_buffer_write_timeout =
 			(tmp ? (1 << tmp) : 0) * cfi->system_interface_info.typ_buffer_write_timeout;
 
-	tmp = bus_read( chain, MAX_BLOCK_ERASE_TIMEOUT_OFFSET << o ) & 0xFF;
+	tmp = bus_read( bus, MAX_BLOCK_ERASE_TIMEOUT_OFFSET << o ) & 0xFF;
 	cfi->system_interface_info.max_block_erase_timeout =
 			(tmp ? (1 << tmp) : 0) * cfi->system_interface_info.typ_block_erase_timeout;
 
-	tmp = bus_read( chain, MAX_CHIP_ERASE_TIMEOUT_OFFSET << o ) & 0xFF;
+	tmp = bus_read( bus, MAX_CHIP_ERASE_TIMEOUT_OFFSET << o ) & 0xFF;
 	cfi->system_interface_info.max_chip_erase_timeout =
 			(tmp ? (1 << tmp) : 0) * cfi->system_interface_info.typ_chip_erase_timeout;
 
 	/* Device geometry - see Table 8 in [1] */
 	/* TODO: Add out of range check */
-	cfi->device_geometry.device_size = 1 << (bus_read( chain, DEVICE_SIZE_OFFSET << o ) & 0xFF);
+	cfi->device_geometry.device_size = 1 << (bus_read( bus, DEVICE_SIZE_OFFSET << o ) & 0xFF);
 
-	cfi->device_geometry.device_interface = read2( chain, FLASH_DEVICE_INTERFACE_OFFSET, o );
+	cfi->device_geometry.device_interface = read2( bus, FLASH_DEVICE_INTERFACE_OFFSET, o );
 
 	/* TODO: Add out of range check */
-	cfi->device_geometry.max_bytes_write = 1 << read2( chain, MAX_BYTES_WRITE_OFFSET, o );
+	cfi->device_geometry.max_bytes_write = 1 << read2( bus, MAX_BYTES_WRITE_OFFSET, o );
 
-	tmp = bus_read( chain, NUMBER_OF_ERASE_REGIONS_OFFSET << o ) & 0xFF;
+	tmp = bus_read( bus, NUMBER_OF_ERASE_REGIONS_OFFSET << o ) & 0xFF;
 	cfi->device_geometry.number_of_erase_regions = tmp;
 
 	cfi->device_geometry.erase_block_regions = malloc( tmp * sizeof (cfi_erase_block_region_t) );
@@ -150,8 +149,8 @@ detect_cfi( chain_t *chain )
 		int i;
 
 		for (i = 0, a = ERASE_BLOCK_REGION_OFFSET; i < tmp; i++, a += 4) {
-			uint32_t y = read2( chain, a, o );
-			uint32_t z = read2( chain, a + 2, o ) << 8;
+			uint32_t y = read2( bus, a, o );
+			uint32_t z = read2( bus, a + 2, o ) << 8;
 			if (z == 0)
 				z = 128;
 			cfi->device_geometry.erase_block_regions[i].erase_block_size = z;
@@ -162,7 +161,7 @@ detect_cfi( chain_t *chain )
 	/* TODO: Intel Primary Algorithm Extended Query Table - see Table 5. in [2] */
 
 	/* Read Array */
-	bus_write( chain, 0, (CFI_CMD_READ_ARRAY1 << 16) | CFI_CMD_READ_ARRAY1 );
+	bus_write( bus, 0, (CFI_CMD_READ_ARRAY1 << 16) | CFI_CMD_READ_ARRAY1 );
 
 	return cfi;
 }
diff --git a/jtag/src/flash-amd.c b/jtag/src/flash-amd.c
index 3b68a9d1..43868bfe 100644
--- a/jtag/src/flash-amd.c
+++ b/jtag/src/flash-amd.c
@@ -37,18 +37,18 @@
 #include <unistd.h>
 
 #include "flash.h"
-#include "chain.h"
+#include "bus.h"
 
 static int dbg = 0;
 
-static int amd_flash_erase_block( chain_t *chain, uint32_t adr );
-static int amd_flash_unlock_block( chain_t *chain, uint32_t adr );
-static int amd_flash_program( chain_t *chain, uint32_t adr, uint32_t data );
-static void amd_flash_read_array( chain_t *chain ); 
+static int amd_flash_erase_block( bus_t *bus, uint32_t adr );
+static int amd_flash_unlock_block( bus_t *bus, uint32_t adr );
+static int amd_flash_program( bus_t *bus, uint32_t adr, uint32_t data );
+static void amd_flash_read_array( bus_t *bus ); 
 
 /* autodetect, we can handle this chip */
 static int 
-amd_flash_autodetect( chain_t *chain, cfi_query_structure_t *cfi )
+amd_flash_autodetect( bus_t *bus, cfi_query_structure_t *cfi )
 {
 	return (cfi->identification_string.pri_id_code == CFI_VENDOR_AMD_SCS);
 }
@@ -97,15 +97,15 @@ amdstatus29( parts *ps, uint32_t adr, uint32_t data )
  * second implementation: see [1], page 30
  */
 static int
-amdstatus( chain_t *chain, uint32_t adr, int data )
+amdstatus( bus_t *bus, uint32_t adr, int data )
 {
 	int timeout;
 	uint32_t togglemask = ((1 << 6) << 16) + (1 << 6); /* DQ 6 */
 	/*  int dq5mask = ((1 << 5) << 16) + (1 << 5); DQ5 */
 
 	for (timeout = 0; timeout < 100; timeout++) {
-		uint32_t data1 = bus_read( chain, adr );
-		uint32_t data2 = bus_read( chain, adr );
+		uint32_t data1 = bus_read( bus, adr );
+		uint32_t data2 = bus_read( bus, adr );
 
 		/*printf("amdstatus %d: %04X/%04X   %04X/%04X \n", */
 		/*	   timeout, data1, data2, (data1 & togglemask), (data2 & togglemask)); */
@@ -143,17 +143,18 @@ amdisprotected( parts *ps, uint32_t adr )
 #endif /* 0 */
 
 static void
-amd_flash_print_info( chain_t *chain )
+amd_flash_print_info( bus_t *bus )
 {
 	int o = 2;
 	int mid, cid, prot;
-	bus_write( chain, 0x0555 << o, 0x00aa00aa );	/* autoselect p29 */
-	bus_write( chain, 0x02aa << o, 0x00550055 );
-	bus_write( chain, 0x0555 << o, 0x00900090 );
-	mid = bus_read( chain, 0x00 << o ) & 0xFFFF;
-	cid = bus_read( chain, 0x01 << o ) & 0xFFFF;
-	prot = bus_read( chain, 0x02 << o ) & 0xFF;
-	amd_flash_read_array( chain );			/* AMD reset */
+
+	bus_write( bus, 0x0555 << o, 0x00aa00aa );	/* autoselect p29 */
+	bus_write( bus, 0x02aa << o, 0x00550055 );
+	bus_write( bus, 0x0555 << o, 0x00900090 );
+	mid = bus_read( bus, 0x00 << o ) & 0xFFFF;
+	cid = bus_read( bus, 0x01 << o ) & 0xFFFF;
+	prot = bus_read( bus, 0x02 << o ) & 0xFF;
+	amd_flash_read_array( bus );			/* AMD reset */
 	printf( "Chip: AMD Flash\n\tManufacturer: " );
 	switch (mid) {
 		case 0x0001:
@@ -176,7 +177,7 @@ amd_flash_print_info( chain_t *chain )
 }
 
 static int
-amd_flash_erase_block( chain_t *chain, uint32_t adr )
+amd_flash_erase_block( bus_t *bus, uint32_t adr )
 {
 	int o = 2;
 
@@ -184,34 +185,34 @@ amd_flash_erase_block( chain_t *chain, uint32_t adr )
 
 	/*	printf("protected: %d\n", amdisprotected(ps, adr)); */
 
-	bus_write( chain, 0x0555 << o, 0x00aa00aa ); /* autoselect p29, sector erase */
-	bus_write( chain, 0x02aa << o, 0x00550055 );
-	bus_write( chain, 0x0555 << o, 0x00800080 );
-	bus_write( chain, 0x0555 << o, 0x00aa00aa );
-	bus_write( chain, 0x02aa << o, 0x00550055 );
-	bus_write( chain, adr, 0x00300030 );
+	bus_write( bus, 0x0555 << o, 0x00aa00aa ); /* autoselect p29, sector erase */
+	bus_write( bus, 0x02aa << o, 0x00550055 );
+	bus_write( bus, 0x0555 << o, 0x00800080 );
+	bus_write( bus, 0x0555 << o, 0x00aa00aa );
+	bus_write( bus, 0x02aa << o, 0x00550055 );
+	bus_write( bus, adr, 0x00300030 );
 
-	if (amdstatus( chain, adr, 0xffff )) {
+	if (amdstatus( bus, adr, 0xffff )) {
 		printf( "flash_erase_block 0x%08X DONE\n", adr );
-		amd_flash_read_array( chain ); /* AMD reset */
+		amd_flash_read_array( bus ); /* AMD reset */
 		return 0;
 	}
 	printf( "flash_erase_block 0x%08X FAILED\n", adr );
 	/* Read Array */
-	amd_flash_read_array( chain ); /* AMD reset */
+	amd_flash_read_array( bus ); /* AMD reset */
 
 	return CFI_INTEL_ERROR_UNKNOWN;
 }
 
 static int
-amd_flash_unlock_block( chain_t *chain, uint32_t adr )
+amd_flash_unlock_block( bus_t *bus, uint32_t adr )
 {
 	printf( "flash_unlock_block 0x%08X IGNORE\n", adr );
 	return 0;
 }
 
 static int
-amd_flash_program( chain_t *chain, uint32_t adr, uint32_t data )
+amd_flash_program( bus_t *bus, uint32_t adr, uint32_t data )
 {
 	int o = 2;
 	int status;
@@ -219,22 +220,22 @@ amd_flash_program( chain_t *chain, uint32_t adr, uint32_t data )
 	if (dbg)
 		printf("\nflash_program 0x%08X = 0x%08X\n", adr, data);
 
-	bus_write( chain, 0x0555 << o, 0x00aa00aa ); /* autoselect p29, program */
-	bus_write( chain, 0x02aa << o, 0x00550055 );
-	bus_write( chain, 0x0555 << o, 0x00A000A0 );
+	bus_write( bus, 0x0555 << o, 0x00aa00aa ); /* autoselect p29, program */
+	bus_write( bus, 0x02aa << o, 0x00550055 );
+	bus_write( bus, 0x0555 << o, 0x00A000A0 );
 
-	bus_write( chain, adr, data );
-	status = amdstatus( chain, adr, data );
+	bus_write( bus, adr, data );
+	status = amdstatus( bus, adr, data );
 	/*	amd_flash_read_array(ps); */
 
 	return !status;
 }
 
 static void
-amd_flash_read_array( chain_t *chain )
+amd_flash_read_array( bus_t *bus )
 {
 	/* Read Array */
-	bus_write( chain, 0x0, 0x00F000F0 ); /* AMD reset */
+	bus_write( bus, 0x0, 0x00F000F0 ); /* AMD reset */
 }
 
 flash_driver_t amd_32_flash_driver = {
diff --git a/jtag/src/flash-intel.c b/jtag/src/flash-intel.c
index 534cdb8a..643ba101 100644
--- a/jtag/src/flash-intel.c
+++ b/jtag/src/flash-intel.c
@@ -41,34 +41,34 @@
 #include <std/mic.h>
 
 #include "flash.h"
-#include "chain.h"
+#include "bus.h"
 
-static int intel_flash_erase_block( chain_t *chain, uint32_t adr );
-static int intel_flash_unlock_block( chain_t *chain, uint32_t adr );
-static int intel_flash_program( chain_t *chain, uint32_t adr, uint32_t data );
-static int intel_flash_erase_block32( chain_t *chain, uint32_t adr );
-static int intel_flash_unlock_block32( chain_t *chain, uint32_t adr );
-static int intel_flash_program32( chain_t *chain, uint32_t adr, uint32_t data );
+static int intel_flash_erase_block( bus_t *bus, uint32_t adr );
+static int intel_flash_unlock_block( bus_t *bus, uint32_t adr );
+static int intel_flash_program( bus_t *bus, uint32_t adr, uint32_t data );
+static int intel_flash_erase_block32( bus_t *bus, uint32_t adr );
+static int intel_flash_unlock_block32( bus_t *bus, uint32_t adr );
+static int intel_flash_program32( bus_t *bus, uint32_t adr, uint32_t data );
 
 /* autodetect, we can handle this chip */
 static int 
-intel_flash_autodetect32( chain_t *chain, cfi_query_structure_t *cfi )
+intel_flash_autodetect32( bus_t *bus, cfi_query_structure_t *cfi )
 {
-	return (cfi->identification_string.pri_id_code == CFI_VENDOR_INTEL_ECS) && (bus_width( chain ) == 32);
+	return (cfi->identification_string.pri_id_code == CFI_VENDOR_INTEL_ECS) && (bus_width( bus ) == 32);
 }
 
 static int 
-intel_flash_autodetect( chain_t *chain, cfi_query_structure_t *cfi )
+intel_flash_autodetect( bus_t *bus, cfi_query_structure_t *cfi )
 {
-	return (cfi->identification_string.pri_id_code == CFI_VENDOR_INTEL_ECS) && (bus_width( chain ) == 16);
+	return (cfi->identification_string.pri_id_code == CFI_VENDOR_INTEL_ECS) && (bus_width( bus ) == 16);
 }
 
-static
-void _intel_flash_print_info( chain_t *chain, int o )
+static void
+_intel_flash_print_info( bus_t *bus, int o )
 {
 	uint32_t mid, cid;
 
-	mid = (bus_read( chain, 0x00 << o ) & 0xFF);
+	mid = (bus_read( bus, 0x00 << o ) & 0xFF);
 	switch (mid) {
 		case STD_MIC_INTEL:
 			printf( "Manufacturer: %s\n", STD_MICN_INTEL );
@@ -79,7 +79,7 @@ void _intel_flash_print_info( chain_t *chain, int o )
 	}
 
 	printf( "Chip: " );
-	cid = (bus_read( chain, 0x01 << o ) & 0xFFFF);
+	cid = (bus_read( bus, 0x01 << o ) & 0xFFFF);
 	switch (cid) {
 		case 0x0016:
 			printf( "28F320J3A\n" );
@@ -114,51 +114,51 @@ void _intel_flash_print_info( chain_t *chain, int o )
 	}
 
 	/* Read Array */
-	bus_write( chain, 0 << o, 0x00FF00FF );
+	bus_write( bus, 0 << o, 0x00FF00FF );
 }
 
-static 
-void intel_flash_print_info( chain_t *chain )
+static void
+intel_flash_print_info( bus_t *bus )
 {
 	int o = 1;
 	/* Intel Primary Algorithm Extended Query Table - see Table 5. in [3] */
 	/* TODO */
 
 	/* Clear Status Register */
-	bus_write( chain, 0 << o, 0x0050 );
+	bus_write( bus, 0 << o, 0x0050 );
 
 	/* Read Identifier Command */
-	bus_write( chain, 0 << 0, 0x0090 );
+	bus_write( bus, 0 << 0, 0x0090 );
 
-	_intel_flash_print_info( chain, o );
+	_intel_flash_print_info( bus, o );
 }
 
-static 
-void intel_flash_print_info32( chain_t *chain )
+static void
+intel_flash_print_info32( bus_t *bus )
 {
 	int o = 2;
 	/* Intel Primary Algorithm Extended Query Table - see Table 5. in [3] */
 	/* TODO */
 
 	/* Clear Status Register */
-	bus_write( chain, 0 << o, 0x00500050 );
+	bus_write( bus, 0 << o, 0x00500050 );
 
 	/* Read Identifier Command */
-	bus_write( chain, 0 << 0, 0x00900090 );
+	bus_write( bus, 0 << 0, 0x00900090 );
 
-	_intel_flash_print_info( chain, o );
+	_intel_flash_print_info( bus, o );
 }
 
 static int
-intel_flash_erase_block( chain_t *chain, uint32_t adr )
+intel_flash_erase_block( bus_t *bus, uint32_t adr )
 {
 	uint16_t sr;
 
-	bus_write( chain, 0, CFI_INTEL_CMD_CLEAR_STATUS_REGISTER );
-	bus_write( chain, adr, CFI_INTEL_CMD_BLOCK_ERASE );
-	bus_write( chain, adr, CFI_INTEL_CMD_CONFIRM );
+	bus_write( bus, 0, CFI_INTEL_CMD_CLEAR_STATUS_REGISTER );
+	bus_write( bus, adr, CFI_INTEL_CMD_BLOCK_ERASE );
+	bus_write( bus, adr, CFI_INTEL_CMD_CONFIRM );
 
-	while (!((sr = bus_read( chain, 0 ) & 0xFE) & CFI_INTEL_SR_READY)) ; 		/* TODO: add timeout */
+	while (!((sr = bus_read( bus, 0 ) & 0xFE) & CFI_INTEL_SR_READY)) ; 		/* TODO: add timeout */
 
 	switch (sr & ~CFI_INTEL_SR_READY) {
 		case 0:
@@ -180,15 +180,15 @@ intel_flash_erase_block( chain_t *chain, uint32_t adr )
 }
 
 static int
-intel_flash_unlock_block( chain_t *chain, uint32_t adr )
+intel_flash_unlock_block( bus_t *bus, uint32_t adr )
 {
 	uint16_t sr;
 
-	bus_write( chain, 0, CFI_INTEL_CMD_CLEAR_STATUS_REGISTER );
-	bus_write( chain, adr, CFI_INTEL_CMD_LOCK_SETUP );
-	bus_write( chain, adr, CFI_INTEL_CMD_UNLOCK_BLOCK );
+	bus_write( bus, 0, CFI_INTEL_CMD_CLEAR_STATUS_REGISTER );
+	bus_write( bus, adr, CFI_INTEL_CMD_LOCK_SETUP );
+	bus_write( bus, adr, CFI_INTEL_CMD_UNLOCK_BLOCK );
 
-	while (!((sr = bus_read( chain, 0 ) & 0xFE) & CFI_INTEL_SR_READY)) ; 		/* TODO: add timeout */
+	while (!((sr = bus_read( bus, 0 ) & 0xFE) & CFI_INTEL_SR_READY)) ; 		/* TODO: add timeout */
 
 	if (sr != CFI_INTEL_SR_READY) {
 		printf("flash: unknown error while unblocking\n");
@@ -198,15 +198,15 @@ intel_flash_unlock_block( chain_t *chain, uint32_t adr )
 }
 
 static int
-intel_flash_program( chain_t *chain, uint32_t adr, uint32_t data )
+intel_flash_program( bus_t *bus, uint32_t adr, uint32_t data )
 {
 	uint16_t sr;
 
-	bus_write( chain, 0, CFI_INTEL_CMD_CLEAR_STATUS_REGISTER );
-	bus_write( chain, adr, CFI_INTEL_CMD_PROGRAM1 );
-	bus_write( chain, adr, data );
+	bus_write( bus, 0, CFI_INTEL_CMD_CLEAR_STATUS_REGISTER );
+	bus_write( bus, adr, CFI_INTEL_CMD_PROGRAM1 );
+	bus_write( bus, adr, data );
 
-	while (!((sr = bus_read( chain, 0 ) & 0xFE) & CFI_INTEL_SR_READY)) ; 		/* TODO: add timeout */
+	while (!((sr = bus_read( bus, 0 ) & 0xFE) & CFI_INTEL_SR_READY)) ; 		/* TODO: add timeout */
 
 	if (sr != CFI_INTEL_SR_READY) {
 		printf("flash: unknown error while programming\n");
@@ -216,15 +216,15 @@ intel_flash_program( chain_t *chain, uint32_t adr, uint32_t data )
 }
 
 static int
-intel_flash_erase_block32( chain_t *chain, uint32_t adr )
+intel_flash_erase_block32( bus_t *bus, uint32_t adr )
 {
 	uint32_t sr;
 
-	bus_write( chain, 0, (CFI_INTEL_CMD_CLEAR_STATUS_REGISTER << 16) | CFI_INTEL_CMD_CLEAR_STATUS_REGISTER );
-	bus_write( chain, adr, (CFI_INTEL_CMD_BLOCK_ERASE << 16) | CFI_INTEL_CMD_BLOCK_ERASE );
-	bus_write( chain, adr, (CFI_INTEL_CMD_CONFIRM << 16) | CFI_INTEL_CMD_CONFIRM );
+	bus_write( bus, 0, (CFI_INTEL_CMD_CLEAR_STATUS_REGISTER << 16) | CFI_INTEL_CMD_CLEAR_STATUS_REGISTER );
+	bus_write( bus, adr, (CFI_INTEL_CMD_BLOCK_ERASE << 16) | CFI_INTEL_CMD_BLOCK_ERASE );
+	bus_write( bus, adr, (CFI_INTEL_CMD_CONFIRM << 16) | CFI_INTEL_CMD_CONFIRM );
 
-	while (((sr = bus_read( chain, 0 ) & 0x00FE00FE) & ((CFI_INTEL_SR_READY << 16) | CFI_INTEL_SR_READY)) != ((CFI_INTEL_SR_READY << 16) | CFI_INTEL_SR_READY)) ; 		/* TODO: add timeout */
+	while (((sr = bus_read( bus, 0 ) & 0x00FE00FE) & ((CFI_INTEL_SR_READY << 16) | CFI_INTEL_SR_READY)) != ((CFI_INTEL_SR_READY << 16) | CFI_INTEL_SR_READY)) ; 		/* TODO: add timeout */
 
 	if (sr != ((CFI_INTEL_SR_READY << 16) | CFI_INTEL_SR_READY)) {
 		printf( "\nsr = 0x%08X\n", sr );
@@ -234,15 +234,15 @@ intel_flash_erase_block32( chain_t *chain, uint32_t adr )
 }
 
 static int
-intel_flash_unlock_block32( chain_t *chain, uint32_t adr )
+intel_flash_unlock_block32( bus_t *bus, uint32_t adr )
 {
 	uint32_t sr;
 
-	bus_write( chain, 0, (CFI_INTEL_CMD_CLEAR_STATUS_REGISTER << 16) | CFI_INTEL_CMD_CLEAR_STATUS_REGISTER );
-	bus_write( chain, adr, (CFI_INTEL_CMD_LOCK_SETUP << 16) | CFI_INTEL_CMD_LOCK_SETUP );
-	bus_write( chain, adr, (CFI_INTEL_CMD_UNLOCK_BLOCK << 16) | CFI_INTEL_CMD_UNLOCK_BLOCK );
+	bus_write( bus, 0, (CFI_INTEL_CMD_CLEAR_STATUS_REGISTER << 16) | CFI_INTEL_CMD_CLEAR_STATUS_REGISTER );
+	bus_write( bus, adr, (CFI_INTEL_CMD_LOCK_SETUP << 16) | CFI_INTEL_CMD_LOCK_SETUP );
+	bus_write( bus, adr, (CFI_INTEL_CMD_UNLOCK_BLOCK << 16) | CFI_INTEL_CMD_UNLOCK_BLOCK );
 
-	while (((sr = bus_read( chain, 0 ) & 0x00FE00FE) & ((CFI_INTEL_SR_READY << 16) | CFI_INTEL_SR_READY)) != ((CFI_INTEL_SR_READY << 16) | CFI_INTEL_SR_READY)) ; 		/* TODO: add timeout */
+	while (((sr = bus_read( bus, 0 ) & 0x00FE00FE) & ((CFI_INTEL_SR_READY << 16) | CFI_INTEL_SR_READY)) != ((CFI_INTEL_SR_READY << 16) | CFI_INTEL_SR_READY)) ; 		/* TODO: add timeout */
 
 	if (sr != ((CFI_INTEL_SR_READY << 16) | CFI_INTEL_SR_READY)) {
 		printf( "\nsr = 0x%08X\n", sr );
@@ -252,15 +252,15 @@ intel_flash_unlock_block32( chain_t *chain, uint32_t adr )
 }
 
 static int
-intel_flash_program32( chain_t *chain, uint32_t adr, uint32_t data )
+intel_flash_program32( bus_t *bus, uint32_t adr, uint32_t data )
 {
 	uint32_t sr;
 
-	bus_write( chain, 0, (CFI_INTEL_CMD_CLEAR_STATUS_REGISTER << 16) | CFI_INTEL_CMD_CLEAR_STATUS_REGISTER );
-	bus_write( chain, adr, (CFI_INTEL_CMD_PROGRAM1 << 16) | CFI_INTEL_CMD_PROGRAM1 );
-	bus_write( chain, adr, data );
+	bus_write( bus, 0, (CFI_INTEL_CMD_CLEAR_STATUS_REGISTER << 16) | CFI_INTEL_CMD_CLEAR_STATUS_REGISTER );
+	bus_write( bus, adr, (CFI_INTEL_CMD_PROGRAM1 << 16) | CFI_INTEL_CMD_PROGRAM1 );
+	bus_write( bus, adr, data );
 
-	while (((sr = bus_read( chain, 0 ) & 0x00FE00FE) & ((CFI_INTEL_SR_READY << 16) | CFI_INTEL_SR_READY)) != ((CFI_INTEL_SR_READY << 16) | CFI_INTEL_SR_READY)) ; 		/* TODO: add timeout */
+	while (((sr = bus_read( bus, 0 ) & 0x00FE00FE) & ((CFI_INTEL_SR_READY << 16) | CFI_INTEL_SR_READY)) != ((CFI_INTEL_SR_READY << 16) | CFI_INTEL_SR_READY)) ; 		/* TODO: add timeout */
 
 	if (sr != ((CFI_INTEL_SR_READY << 16) | CFI_INTEL_SR_READY)) {
 		printf( "\nsr = 0x%08X\n", sr );
@@ -270,17 +270,17 @@ intel_flash_program32( chain_t *chain, uint32_t adr, uint32_t data )
 }
 
 static void
-intel_flash_readarray32( chain_t *chain )
+intel_flash_readarray32( bus_t *bus )
 {
 	/* Read Array */
-	bus_write( chain, 0, 0x00FF00FF );
+	bus_write( bus, 0, 0x00FF00FF );
 }
 
 static void
-intel_flash_readarray( chain_t *chain )
+intel_flash_readarray( bus_t *bus )
 {
 	/* Read Array */
-	bus_write( chain, 0, 0x00FF00FF );
+	bus_write( bus, 0, 0x00FF00FF );
 }
 
 flash_driver_t intel_32_flash_driver = {
diff --git a/jtag/src/flash.c b/jtag/src/flash.c
index aaea1fa8..dc8145bb 100644
--- a/jtag/src/flash.c
+++ b/jtag/src/flash.c
@@ -41,7 +41,6 @@
 #include <arpa/inet.h>
 /* for ntohs */
 
-#include "part.h"
 #include "bus.h"
 #include "flash.h"
 
@@ -61,13 +60,13 @@ flash_driver_t *flash_drivers[] = {
 flash_driver_t *flash_driver = NULL;
 
 void
-set_flash_driver( chain_t *chain, cfi_query_structure_t *cfi )
+set_flash_driver( bus_t *bus, cfi_query_structure_t *cfi )
 {
 	int i;
 	flash_driver = NULL;
 
 	for (i = 0; flash_drivers[i] != NULL; i++)
-		if (flash_drivers[i]->flash_autodetect( chain, cfi )) {
+		if (flash_drivers[i]->flash_autodetect( bus, cfi )) {
 			flash_driver = flash_drivers[i];
 			return;
 		}
@@ -79,16 +78,16 @@ set_flash_driver( chain_t *chain, cfi_query_structure_t *cfi )
 
 /* check for flashmem - set driver */
 static void
-flashcheck( chain_t *chain, cfi_query_structure_t **cfi )
+flashcheck( bus_t *bus, cfi_query_structure_t **cfi )
 {
-	parts_t *ps = chain->parts;
-	part *p = ps->parts[0];
 	int o = 0;
 	flash_driver = NULL;
 
+	bus_prepare( bus );
+
 	printf( "Note: Supported configuration is 2 x 16 bit or 1 x 16 bit only\n" );
 
-	switch (bus_width( chain )) {
+	switch (bus_width( bus )) {
 		case 16:
 			o = 1;
 			break;
@@ -100,31 +99,26 @@ flashcheck( chain_t *chain, cfi_query_structure_t **cfi )
 			return;
 	}
 
-	/* EXTEST */
-	part_set_instruction( p, "EXTEST" );
-	chain_shift_instructions( chain );
-
-	*cfi = detect_cfi( chain );
+	*cfi = detect_cfi( bus );
 	if (!*cfi) {
 		printf( "Flash not found!\n" );
 		return;
 	}
-	set_flash_driver( chain, *cfi );
+	set_flash_driver( bus, *cfi );
 	if (!flash_driver) {
 		printf( "Flash not supported!\n" );
 		return;
 	}
-	flash_driver->flash_print_info( chain );
+	flash_driver->flash_print_info( bus );
 }
 
 void
-flashmsbin( chain_t *chain, FILE *f )
+flashmsbin( bus_t *bus, FILE *f )
 {
-	parts_t *ps = chain->parts;
 	uint32_t adr;
-	cfi_query_structure_t *cfi = 0;
+	cfi_query_structure_t *cfi = NULL;
 
-	flashcheck( chain, &cfi );
+	flashcheck( bus, &cfi );
 	if (!cfi || !flash_driver) {
 		printf( "no flash driver found\n" );
 		return;
@@ -153,9 +147,9 @@ flashmsbin( chain_t *chain, FILE *f )
 		last = (start + len - 1) / (cfi->device_geometry.erase_block_regions[0].erase_block_size * 2);
 		for (; first <= last; first++) {
 			adr = first * cfi->device_geometry.erase_block_regions[0].erase_block_size * 2;
-			flash_unlock_block( chain, adr );
+			flash_unlock_block( bus, adr );
 			printf( "block %d unlocked\n", first );
-			printf( "erasing block %d: %d\n", first, flash_erase_block( chain, adr ) );
+			printf( "erasing block %d: %d\n", first, flash_erase_block( bus, adr ) );
 		}
 	}
 
@@ -184,7 +178,7 @@ flashmsbin( chain_t *chain, FILE *f )
 			printf( "addr: 0x%08X\r", a );
 			fflush(stdout);
 			fread( &data, sizeof data, 1, f );
-			if (flash_program( chain, a, data )) {
+			if (flash_program( bus, a, data )) {
 				printf( "\nflash error\n" );
 				return;
 			}
@@ -194,7 +188,7 @@ flashmsbin( chain_t *chain, FILE *f )
 	}
 	printf( "\n" );
 
-	flash_readarray( chain );
+	flash_readarray( bus );
 
 	fseek( f, 15, SEEK_SET );
 	printf( "verify:\n" );
@@ -223,7 +217,7 @@ flashmsbin( chain_t *chain, FILE *f )
 			printf( "addr: 0x%08X\r", a );
 			fflush( stdout );
 			fread( &data, sizeof data, 1, f );
-			readed = bus_read( chain, a );
+			readed = bus_read( bus, a );
 			if (data != readed) {
 				printf( "\nverify error: 0x%08X vs. 0x%08X at addr %08X\n", 
 					readed, data, a );
@@ -235,23 +229,18 @@ flashmsbin( chain_t *chain, FILE *f )
 	}
 	printf( "\n" );
 
-	/* BYPASS */
-	parts_set_instruction( ps, "BYPASS" );
-	chain_shift_instructions( chain );
-
 	printf( "Done.\n" );
 }
 
 void
-flashmem( chain_t *chain, FILE *f, uint32_t addr )
+flashmem( bus_t *bus, FILE *f, uint32_t addr )
 {
-	parts_t *ps = chain->parts;
 	uint32_t adr;
 	cfi_query_structure_t *cfi = NULL;
 	int *erased;
 	int i;
 
-	flashcheck( chain, &cfi );
+	flashcheck( bus, &cfi );
 	if (!cfi || !flash_driver) {
 		printf( "no flash driver found\n" );
 		return;
@@ -275,9 +264,9 @@ flashmem( chain_t *chain, FILE *f, uint32_t addr )
 		int block_no = adr / (cfi->device_geometry.erase_block_regions[0].erase_block_size * flash_driver->buswidth / 2);
 
 		if (!erased[block_no]) {
-			flash_unlock_block( chain, adr );
+			flash_unlock_block( bus, adr );
 			printf( "\nblock %d unlocked\n", block_no );
-			printf( "erasing block %d: %d\n", block_no, flash_erase_block( chain, adr ) );
+			printf( "erasing block %d: %d\n", block_no, flash_erase_block( bus, adr ) );
 			erased[block_no] = 1;
 		}
 
@@ -289,7 +278,7 @@ flashmem( chain_t *chain, FILE *f, uint32_t addr )
 				data = htons( *((uint16_t *) &b[bc]) );
 			else
 				data = * ((uint32_t *) &b[bc]);
-			if (flash_program( chain, adr, data )) {
+			if (flash_program( bus, adr, data )) {
 				printf( "\nflash error\n" );
 				return;
 			}
@@ -298,7 +287,7 @@ flashmem( chain_t *chain, FILE *f, uint32_t addr )
 	}
 	printf( "\n" );
 
-	flash_readarray( chain );
+	flash_readarray( bus );
 
 	if (flash_driver->buswidth == 4) {			/* TODO: not available in 1 x 16 bit mode */
 	fseek( f, 0, SEEK_SET );
@@ -318,7 +307,7 @@ flashmem( chain_t *chain, FILE *f, uint32_t addr )
 
 		printf( "addr: 0x%08X\r", adr );
 		fflush( stdout );
-		readed = bus_read( chain, adr );
+		readed = bus_read( bus, adr );
 		if (data != readed) {
 			printf( "\nverify error:\nreaded: 0x%08X\nexpected: 0x%08X\n", readed, data );
 			return;
@@ -329,13 +318,5 @@ flashmem( chain_t *chain, FILE *f, uint32_t addr )
 	} else
 		printf( "TODO: Verify is not available in 1 x 16 bit mode.\n" );
 
-	/* BYPASS */
-	parts_set_instruction( ps, "BYPASS" );
-	chain_shift_instructions( chain );
-
 	free( erased );
 }
-
-
-
-
diff --git a/jtag/src/flash.h b/jtag/src/flash.h
index 9889486c..faa05b73 100644
--- a/jtag/src/flash.h
+++ b/jtag/src/flash.h
@@ -31,18 +31,17 @@
 
 #include "part.h"
 #include "bus.h"
-#include "chain.h"
 
 typedef struct {
 	int buswidth;		/* supported bus width, 1/2/4 bytes */
 	const char *name;
 	const char *description;
-	int (*flash_autodetect)( chain_t *, cfi_query_structure_t * );
-	void (*flash_print_info)( chain_t * );
-	int (*flash_erase_block)( chain_t *, uint32_t );
-	int (*flash_unlock_block)( chain_t *, uint32_t );
-	int (*flash_program)( chain_t *, uint32_t, uint32_t );
-	void (*flash_readarray)( chain_t *chain );
+	int (*flash_autodetect)( bus_t *bus, cfi_query_structure_t *cfi );
+	void (*flash_print_info)( bus_t *bus );
+	int (*flash_erase_block)( bus_t *bus, uint32_t adr );
+	int (*flash_unlock_block)( bus_t *bus, uint32_t adr );
+	int (*flash_program)( bus_t *bus, uint32_t adr, uint32_t data );
+	void (*flash_readarray)( bus_t *bus );
 } flash_driver_t;
 
 extern flash_driver_t *flash_driver;
@@ -54,7 +53,7 @@ extern flash_driver_t *flash_drivers[];
 #define flash_program         flash_driver->flash_program
 #define flash_readarray       flash_driver->flash_readarray
 
-extern void set_flash_driver( chain_t *chain, cfi_query_structure_t *cfi );
+extern void set_flash_driver( bus_t *bus, cfi_query_structure_t *cfi );
 
 #define	CFI_INTEL_ERROR_UNKNOWN				1
 #define	CFI_INTEL_ERROR_UNSUPPORTED			2
diff --git a/jtag/src/jtag.c b/jtag/src/jtag.c
index 738c6b0c..278f782d 100644
--- a/jtag/src/jtag.c
+++ b/jtag/src/jtag.c
@@ -52,7 +52,7 @@ ssize_t getline( char **lineptr, size_t *n, FILE *stream );
 #endif
 
 chain_t *chain = NULL;
-bus_driver_t *bus_driver = NULL;
+bus_t *bus = NULL;
 
 static char *
 get_token( char *buf )
@@ -84,7 +84,7 @@ jtag_create_jtagdir( void )
 	strcat( jdir, JTAGDIR );
 
 	/* Create the directory if it doesn't exists. */
-	mkdir( jdir, 0755 );
+	mkdir( jdir, S_IRWXU | S_IRGRP | S_IXGRP | S_IROTH | S_IXOTH );
 
 	free( jdir );
 }
@@ -269,6 +269,10 @@ jtag_parse_line( char *line )
 				return 1;
 			}
 
+			if (bus) {
+				bus->free( bus );
+				bus = NULL;
+			}
 			parts_free( chain->parts );
 			chain->parts = detect_parts( chain, JTAG_DATA_DIR );
 			if (!chain->parts->len) {
@@ -282,11 +286,11 @@ jtag_parse_line( char *line )
 			parts_set_instruction( chain->parts, "BYPASS" );
 			chain_shift_instructions( chain );
 			if (strcmp( chain->parts->parts[0]->part, "SA1110" ) == 0)
-				bus_driver = &sa1110_bus_driver;
+				bus = new_sa1110_bus( chain, 0 );
 			if (strcmp( chain->parts->parts[0]->part, "PXA250" ) == 0)
-				bus_driver = &pxa250_bus_driver;
+				bus = new_pxa250_bus( chain, 0 );
 			if (strcmp( chain->parts->parts[0]->part, "IXP425" ) == 0)
-				bus_driver = &ixp425_bus_driver;
+				bus = new_ixp425_bus( chain, 0 );
 			return 1;
 		}
 
@@ -334,9 +338,9 @@ jtag_parse_line( char *line )
 				return 1;
 			}
 			if (msbin) 
-				flashmsbin( chain, f );
+				flashmsbin( bus, f );
 			else
-				flashmem( chain, f, addr );
+				flashmem( bus, f, addr );
 			fclose( f );
 			return 1;
 		}
@@ -392,7 +396,7 @@ jtag_parse_line( char *line )
 				printf( _("Unable to create file `%s'!\n"), t );
 				return 1;
 			}
-			readmem( chain, f, addr, len );
+			readmem( bus, f, addr, len );
 
 			fclose( f );
 			return 1;
@@ -414,7 +418,7 @@ jtag_parse_line( char *line )
 				return 1;
 			}
 
-			detectflash( chain );
+			detectflash( bus );
 			return 1;
 		}
 
@@ -841,6 +845,10 @@ main( int argc, const char **argv )
 		}
 	}
 
+	if (bus) {
+		bus->free( bus );
+		bus = NULL;
+	}
 	chain_free( chain );
 
 	return 0;
diff --git a/jtag/src/jtag.h b/jtag/src/jtag.h
index b41d2bea..d7628202 100644
--- a/jtag/src/jtag.h
+++ b/jtag/src/jtag.h
@@ -32,17 +32,18 @@
 
 #include "part.h"
 #include "chain.h"
+#include "bus.h"
 
 parts_t *detect_parts( chain_t* chain, char *db_path );
-void detectflash( chain_t *chain );
-void readmem( chain_t *chain, FILE *f, uint32_t addr, uint32_t len );
-void flashmem( chain_t *chain, FILE *f, uint32_t addr );
-void flashmsbin( chain_t *chain, FILE *f );
+void detectflash( bus_t *bus );
+void readmem( bus_t *bus, FILE *f, uint32_t addr, uint32_t len );
+void flashmem( bus_t *bus, FILE *f, uint32_t addr );
+void flashmsbin( bus_t *bus, FILE *f );
 
 void help( const char *cmd );
 
 void discovery( chain_t *chain, const char *filename );
 
-cfi_query_structure_t *detect_cfi( chain_t *chain );
+cfi_query_structure_t *detect_cfi( bus_t *bus );
 
 #endif /* JTAG_H */
diff --git a/jtag/src/readmem.c b/jtag/src/readmem.c
index 7bda247b..a02665bd 100644
--- a/jtag/src/readmem.c
+++ b/jtag/src/readmem.c
@@ -43,27 +43,25 @@
 #include <arpa/inet.h>
 /* for ntohs */
 
-#include "part.h"
 #include "bus.h"
 #include "flash.h"
-#include "chain.h"
 
 void
-detectflash( chain_t *chain )
+detectflash( bus_t *bus )
 {
-	parts_t *ps = chain->parts;
-	part *p = ps->parts[0];
 	int o = 0;
 	cfi_query_structure_t *cfi;
 
-	if (!bus_driver) {
-		printf( "Error: Missing bus_driver!\n" );
+	if (!bus) {
+		printf( "Error: Missing bus driver!\n" );
 		return;
 	}
 
+	bus_prepare( bus );
+
 	printf( "Note: Supported configuration is 2 x 16 bit or 1 x 16 bit only\n" );
 
-	switch (bus_width( chain )) {
+	switch (bus_width( bus )) {
 		case 16:
 			o = 1;
 			break;
@@ -75,11 +73,7 @@ detectflash( chain_t *chain )
 			return;
 	}
 
-	/* EXTEST */
-	part_set_instruction( p, "EXTEST" );
-	chain_shift_instructions( chain );
-
-	cfi = detect_cfi( chain );
+	cfi = detect_cfi( bus );
 	if (!cfi) {
 		printf( "Flash not found!\n" );
 		return;
@@ -211,36 +205,32 @@ detectflash( chain_t *chain )
 		}
 	}
 
-	set_flash_driver( chain, cfi );
+	set_flash_driver( bus, cfi );
 	if (flash_driver)
-		flash_driver->flash_print_info( chain );
+		flash_driver->flash_print_info( bus );
 }
 
 void
-readmem( chain_t *chain, FILE *f, uint32_t addr, uint32_t len )
+readmem( bus_t *bus, FILE *f, uint32_t addr, uint32_t len )
 {
-	parts_t *ps = chain->parts;
-	part *p = ps->parts[0];
 	int step = 0;
 	uint32_t a;
 	int bc = 0;
 
-	if (!bus_driver) {
-		printf( "Error: Missing bus_driver!\n" );
+	if (!bus) {
+		printf( "Error: Missing bus driver!\n" );
 		return;
 	}
 
-	step = bus_width( chain ) / 8;
+	bus_prepare( bus );
+
+	step = bus_width( bus ) / 8;
 
 	if (step == 0) {
 		printf( "Unknown bus width!\n" );
 		return;
 	}
 
-	/* EXTEST */
-	part_set_instruction( p, "EXTEST" );
-	chain_shift_instructions( chain );
-
 	addr = addr & (~(step - 1));
 	len = (len + step - 1) & (~(step - 1));
 
@@ -253,7 +243,7 @@ readmem( chain_t *chain, FILE *f, uint32_t addr, uint32_t len )
 	}
 
 	printf( "reading:\n" );
-	bus_read_start( chain, addr );
+	bus_read_start( bus, addr );
 	for (a = addr + step; a <= addr + len; a += step) {
 		uint32_t d = 0;
 		uint16_t d16 = 0;
@@ -262,15 +252,15 @@ readmem( chain_t *chain, FILE *f, uint32_t addr, uint32_t len )
 
 		if (a < addr + len) {
 			if (step == 2)
-				d16 = bus_read_next( chain, a );
+				d16 = bus_read_next( bus, a );
 			else
-				d = bus_read_next( chain, a );
+				d = bus_read_next( bus, a );
 		}
 		else {
 			if (step == 2)
-				d16 = bus_read_end( chain );
+				d16 = bus_read_end( bus );
 			else
-				d = bus_read_end( chain );
+				d = bus_read_end( bus );
 		}
 		if (step == 2)
 			*((uint16_t *) &b[bc]) = ntohs(d16);