diff --git a/src/arch/i386/config/make.base b/src/arch/i386/config/make.base
index 2a428a0cff..a7c2b79a37 100644
--- a/src/arch/i386/config/make.base
+++ b/src/arch/i386/config/make.base
@@ -1,6 +1,7 @@
 option _ROMBASE=0xf0000
 option _RAMBASE=0x4000
 option ROM_IMAGE_SIZE=65536
+option PAYLOAD_SIZE=458752
 
 # By default we only have one cpu 
 option MAX_CPUS=1
@@ -24,7 +25,7 @@ dir /src/config
 
 makerule all : romimage ;
 makerule floppy : all ; mcopy -o romimage a:
-makerule romimage : linuxbios.rom payload.bin.gz.block ; cat payload.bin.gz.block linuxbios.rom > romimage
+makerule romimage : linuxbios.rom payload.block ; cat payload.block linuxbios.rom > romimage
 
 
 makerule linuxbios.rom: linuxbios.strip ; 
@@ -36,12 +37,13 @@ addaction linuxbios.rom dd if=linuxbios.strip of=linuxbios.rom bs=1 seek=`expr $
 makerule mkrom: $(TOP)/mkrom/mkrom.c ; $(CC) -o mkrom $<
 
 
-makerule payload.bin.gz.block : payload.bin.gz ; dd conv=sync bs=448k if=payload.bin.gz of=payload.bin.gz.block
-makerule payload.bin.gz: payload.bin ;gzip -f -3 payload.bin
-makerule payload.bin: $(PAYLOAD) ;  objcopy -O binary -R .note -R .comment -S $< payload.bin
+makerule payload.block : $(if $(PAYLOAD),$(PAYLOAD), linux.bin.gz) ; dd conv=sync bs=$(PAYLOAD_SIZE) if=$< of=$@
+
+makerule linux.bin.gz: linux.bin ;gzip -f -3 linux.bin
+makerule linux.bin: $(LINUX) ;  objcopy -O binary -R .note -R .comment -S $< $@
 
 
-addaction clean rm -f romimage mkrom payload.*
+addaction clean rm -f romimage mkrom linux.* payload.*
 
 # do standard config files that the user need not specify
 # for now, this is just 'lib', but it may be more later. 
diff --git a/src/config/Config b/src/config/Config
index e074fdf953..3e8134cf14 100644
--- a/src/config/Config
+++ b/src/config/Config
@@ -25,9 +25,12 @@ addaction linuxbios nm -n linuxbios > linuxbios.map
 makerule linuxbios.a : $(OBJECTS-1) ; rm -f linuxbios.a
 addaction linuxbios.a ar cr linuxbios.a $(OBJECTS-1)
 
-makerule crt0.s: crt0.S ; $(CPP) $(CPPFLAGS) -I$(TOP)/src $< > crt0.s
+makerule crt0.s: crt0.S ; @echo "$(CPP) ... $< > $crt0.s "
+addaction crt0.s @$(CPP) $(CPPFLAGS) -I$(TOP)/src $< > crt0.s
+
+makerule crt0.o : crt0.s; @echo $(CC) ... -o $@ $<
+addaction crt0.o @$(CC) -c $(CPU_OPT) -o $@ $<
 
-makerule crt0.o : crt0.s; $(CC) $(CPU_OPT) -c crt0.s
 
 makerule etags: $(SOURCES) ; etags $(SOURCES)
 makerule tags: $(SOURCES) ; ctags $(SOURCES)
diff --git a/src/include/part/fallback_boot.h b/src/include/part/fallback_boot.h
index 95b0c210a8..468e5cef67 100644
--- a/src/include/part/fallback_boot.h
+++ b/src/include/part/fallback_boot.h
@@ -3,11 +3,7 @@
 
 #if !defined(ASSEMBLY)
 
-#if USE_FALLBACK_BOOT
 void boot_successful(void);
-#  else
-#    define boot_successful()
-#endif
 
 #endif /* ASSEMBLY */
 
diff --git a/src/lib/Config b/src/lib/Config
index 338c78cef8..66ca841250 100644
--- a/src/lib/Config
+++ b/src/lib/Config
@@ -15,5 +15,5 @@ object elfboot.o
 object do_inflate.o
 object floppy_subr.o
 object delay.o
-object fallback_boot.o USE_FALLBACK_BOOT
+object fallback_boot.o
 object compute_ip_checksum.o
\ No newline at end of file
diff --git a/src/mainboard/intel/l440gx/Config b/src/mainboard/intel/l440gx/Config
index 213924401e..48a927aa64 100644
--- a/src/mainboard/intel/l440gx/Config
+++ b/src/mainboard/intel/l440gx/Config
@@ -12,9 +12,54 @@ mainboardinit superio/NSC/pc87309/setup_serial.inc
 mainboardinit pc80/serial.inc
 mainboardinit arch/i386/lib/console.inc
 
+
+#
+# Inspired by the cache as ram testing...
+#
+
+biosbase 0xffff0000
+rambase 0x00000800
+option XIP_ROM_BASE=0xffff0000
+option XIP_ROM_SIZE=0x10000
+option STACK_SIZE=0x2000
+
+#######
+## Testing of the cache ram idea on a PIII
+#######
+
+option CACHE_RAM_BASE=0xfff00000
+option CACHE_RAM_SIZE=0x00010000
+option USE_CACHE_RAM=1
+nooption USE_DEFAULT_LAYOUT
+option RAMTEST=1
+
+mainboardinit cpu/i786/earlymtrr.inc
+#mainboardinit ram/ramtest.inc
+mainboardinit cpu/p6/cache_ram_init.inc
+#mainboardinit mainboard/supermicro/p4dc6/cache_test.inc
+mainboardinit cpu/p6/cache_ram_start.inc
+mainboardinit cpu/p6/cache_ram_fini.inc
+
+option USE_GENERIC_SDRAM=1
+option USE_GENERIC_SDRAM_ENABLE=1
+option USE_PIIX4E_SMBUS=1
+option USE_GENERIC_DUMP_SPD=1
+option USE_GENERIC_ZERO_ECC_SDRAM=1
+option USE_RAMTEST=1
+object mainboard_raminit.c
+
+option SMBUS_MEM_DEVICE_START=0x50
+option SMBUS_MEM_DEVICE_END=0x53
+option SMBUS_MEM_DEVICE_INC=1
+dir /src/sdram
+dir /src/ram
+
+
+#######
+
 northbridge intel/440gx
 southbridge intel/piix4e
-mainboardinit cpu/p6/earlymtrr.inc
+#mainboardinit cpu/p6/earlymtrr.inc
 
 superio NSC/pc87309
 
diff --git a/src/mainboard/supermicro/p4dc6/Config b/src/mainboard/supermicro/p4dc6/Config
index a9b14d0789..f44ef990c6 100644
--- a/src/mainboard/supermicro/p4dc6/Config
+++ b/src/mainboard/supermicro/p4dc6/Config
@@ -14,21 +14,19 @@ option CACHE_RAM_BASE=0xfff70000
 option CACHE_RAM_SIZE=0x00010000
 nooption USE_DEFAULT_LAYOUT
 option STACK_SIZE=0x2000
-option USE_FALLBACK_BOOT=1
+option USE_FALLBACK_IMAGE=0
+option ROM_SIZE=524288
 
-#option USE_RAMTEST=1
-#dir /src/ram
+expr USE_NORMAL_IMAGE=!USE_FALLBACK_IMAGE
+expr ROM_SECTION_SIZE  =(USE_FALLBACK_IMAGE*65536)+(USE_NORMAL_IMAGE*(ROM_SIZE - 65536))
+expr ROM_SECTION_OFFSET=(USE_FALLBACK_IMAGE*(ROM_SIZE-65536))+(USE_NORMAL_IMAGE*0)
+
+expr ZKERNEL_START =(0xffffffff - ROM_SIZE + ROM_SECTION_OFFSET + 1)
+expr PAYLOAD_SIZE  =ROM_SECTION_SIZE - ROM_IMAGE_SIZE
+expr _ROMBASE      =ZKERNEL_START + PAYLOAD_SIZE
+expr XIP_ROM_SIZE = 65536
+expr XIP_ROM_BASE = _ROMBASE + ROM_IMAGE_SIZE - XIP_ROM_SIZE
 
-#/* falback */
-option ZKERNEL_START=0xffff0000
-option _ROMBASE=     0xffff8000 
-option XIP_ROM_BASE= 0xffff8000
-option XIP_ROM_SIZE= 0x00008000
-##/* normal image */
-#option ZKERNEL_START=0xfff80000
-#option _ROMBASE=     0xfffe8000 
-#option XIP_ROM_BASE= 0xfffe8000
-#option XIP_ROM_SIZE= 0x00008000
 
 mainboardinit northbridge/intel/82860/reset_test.inc
 mainboardinit arch/i386/lib/noop_failover.inc USE_NORMAL_IMAGE
diff --git a/src/mainboard/supermicro/p4dc6/example-fallback.config b/src/mainboard/supermicro/p4dc6/example-fallback.config
new file mode 100644
index 0000000000..f52fa1547b
--- /dev/null
+++ b/src/mainboard/supermicro/p4dc6/example-fallback.config
@@ -0,0 +1,37 @@
+# This will make a target directory of ./winfast
+# Note that this is RELATIVE TO WHERE YOU ARE WHEN YOU RUN THE 
+# CONFIG TOOL. Make it absolute if you like
+target /home/eric/projects/freebios/p4dc6-build/normal
+
+mainboard supermicro/p4dc6
+
+option USE_FALLBACK_IMAGE=1
+option ROM_SIZE=524288
+#option ROM_SIZE=1048576
+option ROM_IMAGE_SIZE=32768
+
+
+# Enable Serial Console for debugging
+# It will come up at 115200,8n1
+option SERIAL_CONSOLE=1
+#nooption SERIAL_CONSOLE
+#option TTYS0_BAUD=9600
+option TTYS0_BAUD=115200
+
+# Generate debugging output
+option DEFAULT_CONSOLE_LOGLEVEL=9
+option MAXIMUM_CONSOLE_LOGLEVEL=6
+#option DEFAULT_CONSOLE_LOGLEVEL=5
+
+# Select the boot device
+#option USE_CACHE_RAM=1
+option USE_GENERIC_ROM=1
+#option BOOT_FLOPPY=1
+#option USE_SERIAL_FILL_INBUF=1
+#option BOOT_IDE=1
+
+# Use the elf bootloader
+option USE_ELF_BOOT=1
+
+# Load etherboot with the elf bootloader
+payload ../eepro100.ebi
diff --git a/src/mainboard/supermicro/p4dc6/example-normal.config b/src/mainboard/supermicro/p4dc6/example-normal.config
new file mode 100644
index 0000000000..a619525dc7
--- /dev/null
+++ b/src/mainboard/supermicro/p4dc6/example-normal.config
@@ -0,0 +1,37 @@
+# This will make a target directory of ./winfast
+# Note that this is RELATIVE TO WHERE YOU ARE WHEN YOU RUN THE 
+# CONFIG TOOL. Make it absolute if you like
+target /home/eric/projects/freebios/p4dc6-build/normal
+
+mainboard supermicro/p4dc6
+
+option USE_FALLBACK_IMAGE=0
+option ROM_SIZE=524288
+#option ROM_SIZE=1048576
+option ROM_IMAGE_SIZE=49152
+
+
+# Enable Serial Console for debugging
+# It will come up at 115200,8n1
+option SERIAL_CONSOLE=1
+#nooption SERIAL_CONSOLE
+#option TTYS0_BAUD=9600
+option TTYS0_BAUD=115200
+
+# Generate debugging output
+option DEFAULT_CONSOLE_LOGLEVEL=9
+option MAXIMUM_CONSOLE_LOGLEVEL=8
+#option DEFAULT_CONSOLE_LOGLEVEL=5
+
+# Select the boot device
+#option USE_CACHE_RAM=1
+option USE_GENERIC_ROM=1
+#option BOOT_FLOPPY=1
+#option USE_SERIAL_FILL_INBUF=1
+#option BOOT_IDE=1
+
+# Use the elf bootloader
+option USE_ELF_BOOT=1
+
+# Load etherboot with the elf bootloader
+payload ../eepro100.ebi
diff --git a/src/mainboard/supermicro/p4dc6/mainboard.c b/src/mainboard/supermicro/p4dc6/mainboard.c
index 4781f7500e..c6a1d3424e 100644
--- a/src/mainboard/supermicro/p4dc6/mainboard.c
+++ b/src/mainboard/supermicro/p4dc6/mainboard.c
@@ -39,7 +39,6 @@ void mainboard_fixup(void)
 #endif
 	ich2_power_after_power_fail(1);
 	w832627hf_power_after_power_fail(POWER_ON);
-	printk_notice("Please add a mainboard_fixup!\n");
 	return;
 }
 
diff --git a/src/rom/rom_fill_inbuf.c b/src/rom/rom_fill_inbuf.c
index 81249a65e2..8398a306d0 100644
--- a/src/rom/rom_fill_inbuf.c
+++ b/src/rom/rom_fill_inbuf.c
@@ -67,8 +67,8 @@ static byte_offset_t rom_read_bytes(int cp, void *vdest, byte_offset_t count)
 			return bytes;
 		}
 		length = K64 - block_offset;
-		if (length > count) {
-			length = count;
+		if (length > (count - bytes)) {
+			length = count - bytes;
 		}
 		if (cp) {
 			memcpy(dest, nvram + block_offset, length);
diff --git a/src/southbridge/intel/82801/ich2_cpu.c b/src/southbridge/intel/82801/ich2_cpu.c
index 6477815d89..0c1323ef73 100644
--- a/src/southbridge/intel/82801/ich2_cpu.c
+++ b/src/southbridge/intel/82801/ich2_cpu.c
@@ -2,20 +2,29 @@
 #include <pci_ids.h>
 #include <southbridge/intel/82801.h>
 #include <printk.h>
+#include <part/hard_reset.h>
+#include <part/fallback_boot.h>
 #include "82801.h"
 
 void ich2_set_cpu_multiplier(unsigned multiplier)
 {
-	u32 dword;
+	u32 dword, old_dword;
 	struct pci_dev *dev;
+	unsigned old_multiplier;
 	dev = pci_find_device(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801BA_1F0, 0);
 	if (!dev) {
 		printk_err("Cannot find device %08x:%08x\n",
 			PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801BA_1F0);
 		return;
 	}
-	pci_read_config_dword(dev, GEN_STS, &dword);
+	pci_read_config_dword(dev, GEN_STS, &old_dword);
+	dword = old_dword;
 	dword &= ~((1 << 12) - (1 << 8));
 	dword |= (multiplier & 0xf) << 8;
-	pci_write_config_dword(dev, GEN_STS, dword);
+	if (dword != old_dword) {
+		pci_write_config_dword(dev, GEN_STS, dword);
+		printk_info("Rebooting to change the cpu multiplier\n");
+		boot_successful();
+		hard_reset();
+	}
 }
diff --git a/util/config/NLBConfig.py b/util/config/NLBConfig.py
index 2757fa0840..2d782a8625 100644
--- a/util/config/NLBConfig.py
+++ b/util/config/NLBConfig.py
@@ -11,7 +11,6 @@
 # $Id$
 # Author:
 # Modified by Jan Kok to improve readability of Makefile, etc.
-
 import sys
 import os
 import re
@@ -31,7 +30,7 @@ crt0base = ''
 ldscriptbase = ''
 
 makeoptions = {}
-makenooptions = {}
+makeexpressions = []
 
 # Key is the rule name. Value is a mkrule object.
 makebaserules = {}
@@ -45,6 +44,67 @@ target_dir = ''
 objectrules = []
 userdefines = []
 
+
+# -----------------------------------------------------------------------------
+#                    Error Handling
+# -----------------------------------------------------------------------------
+
+class location:
+	class place:
+		def __init__(self, file, line, command):
+			self.file = file
+			self.line = line
+			self.command = command
+		def next_line(self, command):
+			self.line = self.line + 1
+			self.command = command
+		def at(self):
+			return "%s:%d" % (self.file, self.line)
+	
+	def __init__ (self):
+		self.stack = []
+
+	def file(self):
+		return self.stack[-1].file
+	def line(self):
+		 return self.stack[-1].line
+	def command(self):
+		return self.stack[-1].command
+
+	def push_file(self, file):
+		self.stack.append(self.place(file, 0, ""))
+	def pop_file(self):
+		self.stack.pop()
+	def next_line(self, command):
+		self.stack[-1].next_line(command)
+	def at(self):
+		return self.stack[-1].at()
+loc = location()
+
+def fatal(string):	
+	global loc
+	size = len(loc.stack)
+	i = 0
+	while(i < size -1):
+		print loc.stack[i].at()
+		i = i + 1
+	print "%s: %s"% (loc.at(), string)
+	sys.exit(1)
+
+def warning(string):
+	global loc
+	print "===> Warning:"
+	size = len(loc.stack)
+	i = 0
+	while(i < size -1):
+		print loc.stack[i].at()
+		i = i + 1
+	print "%s: %s"% (loc.at(), string)
+
+# -----------------------------------------------------------------------------
+#                    Rules
+# -----------------------------------------------------------------------------
+
 # this is the absolute base rule, and so is very special. 
 mainrulelist = "all"
 
@@ -80,15 +140,14 @@ class mkrule:
 	# This defines the function mkrule(target, depends, action).
 	# It creates a makerule object and records it for later recall.
 	def __init__(self, target, depends, actions):
-		self.whence = current_config_file()
+		self.whence = loc.file()
 		self.comments = []       # list of strings
 		self.target = target     # string
 		self.depends = depends   # string of dependency names
 		self.actions = actions   # list of strings
 		if makebaserules.has_key(target):
-			print "===> Warning: makerule for target '%s' in file" % target
-			print current_config_file(), "is replacing previous definition in file"
-			print makebaserules[target].whence
+			warning("makerule for target '%s' is replacing previous defintion in file %s" % 
+			(target, makebaserules[target].whence))
 		else:
 			# Keep a list of targets so we can output the rules
 			# in the order that they are defined.
@@ -127,22 +186,12 @@ class mkrule:
 # -----------------------------------------------------------------------------
 #                        Command parsing functions
 # -----------------------------------------------------------------------------
-
-# Keep track of nested config files, for error reporting.
-config_file_stack = []
-def current_config_file():
-	return config_file_stack[-1]
-
-# The command being processed, for error reporting.
-current_command = ''
-
+		
 # Match a compiled pattern with a string, die if fails, return list of groups.
 def match(pattern, string):
 	m = pattern.match(string)
 	if not m:
-		print "\nBad command syntax: ", current_command
-		print "in file", current_config_file()
-		sys.exit(1)
+		fatal("Bad command sytax")
 	return m.groups()
 
 # A common pattern: <nonwhitespace><whitespace><rest of line>
@@ -164,8 +213,7 @@ splitargs_re = re.compile(r'(\S*)\s*(.*)')
 # instance of the BIOS.  The target directory will be $(TOP)/<target-name>. 
 def target(dir, targ_name):
 	global target_dir
-	target_dir = os.path.join(os.path.dirname(current_config_file()),
-				targ_name)
+	target_dir = os.path.join(os.path.dirname(loc.file()), targ_name)
 	if not os.path.isdir(target_dir):
 		print 'Creating directory', target_dir
 		os.makedirs(target_dir)
@@ -179,7 +227,7 @@ def handleconfig(dir):
 	if os.path.isfile(file):
 		doconfigfile(dir, file)
 	else:
-		print "===> Warning: %s not found" % file
+		warning("%s not found" % file)
 
 # type is the command name, e.g. 'northbridge'
 # name is the path arg that followed the command
@@ -410,7 +458,7 @@ def makerule(dir, rule):
 def addaction(dir, rule):
 	(target, action) = match(splitargs_re, rule)
 	if not makebaserules.has_key(target):
-	    print "===> Warning: Need 'makerule %s ...' before addaction in %s" % (target, current_config_file())
+		warning("Need 'makerule %s ...' before addaction" % (target))
         makebaserules[target].addaction(action)
 
 # COMMAND: adddepend <target> <dependency>
@@ -420,7 +468,7 @@ def addaction(dir, rule):
 def adddepend(dir, rule):
 	(target, depend) = match(splitargs_re, rule)
 	if not makebaserules.has_key(target):
-	    print "===> Warning: Need 'makerule %s ...' before adddepend in %s" % (target, current_config_file())
+		warning("Need 'makerule %s ...' before adddepend" % (target))
         makebaserules[target].adddepend(depend)
 
 # COMMAND: makedefine <stuff>
@@ -429,17 +477,197 @@ def adddepend(dir, rule):
 def makedefine(dir, rule): 
 	userdefines.append(rule)
 
+
+class mkexpr:
+	class identifier:
+		def __init__ (self, name):
+			self.name = name
+		def bc(self):
+			return "($(" + self.name + "))"
+		def perl(self):
+			return "($(" + self.name + "))"
+
+	class constant:
+		def __init__ (self, value):
+			self.value = value
+		def bc(self):
+			return "(" + self.value + ")"
+		def perl(self):
+			return "(" + self.value + ")"
+
+	class unary:
+		def __init__ (self, op, right):
+			self.op = op
+			self.right = right
+
+		def bc(self):
+			rstring = self.right.bc()
+			if (self.op == "!"):
+				result = "!" + rstring
+			elif (self.op == "-"):
+				result = "-" + rstring
+			return "(" + result + ")"
+
+		def perl(self):
+			rstring = self.right.perl()
+			if (self.op == "!"):
+				result = "!" + rstring
+			elif (self.op == "-"):
+				result = "-" + rstring
+			return "(" + result + ")"
+		
+	class binary:
+		def __init__(self, op, left, right):
+			self.op = op
+			self.left = left
+			self.right = right
+
+		def bc(self):
+			lstring = self.left.bc()
+			rstring = self.right.bc()
+			if (self.op == "&"):
+				result = lstring + "&&" + rstring
+			elif (self.op == "|"):
+				result = lstring + "||" + rstring
+			elif (self.op == "+"):
+				result = lstring + "+" + rstring
+			elif (self.op == "-"):
+				result = lstring + "-" + rstring
+			elif (self.op == "*"):
+				result = lstring + "*" + rstring
+			elif (self.op == "/"):
+				result = lstring + "/" + rstring
+			elif (self.op == "<<"):
+				result = lstring + "*(2^" + rstring + ") "
+			elif (self.op == ">>"):
+				result = lstring + "/(2^" + rstring + ") "
+			return "(" + result + ")"
+
+
+		def perl(self):
+			lstring = self.left.perl()
+			rstring = self.right.perl()
+			if (self.op == "&"):
+				result = lstring + "&&" + rstring
+			elif (self.op == "|"):
+				result = lstring + "||" + rstring
+			elif (self.op == "+"):
+				result = lstring + "+" + rstring
+			elif (self.op == "-"):
+				result = lstring + "-" + rstring
+			elif (self.op == "*"):
+				result = lstring + "*" + rstring
+			elif (self.op == "/"):
+				result = lstring + "/" + rstring
+			elif (self.op == "<<"):
+				result = lstring + "<<" + rstring + ") "
+			elif (self.op == ">>"):
+				result = lstring + ">>" + rstring + ") "
+			return "(" + result + ")"
+
+	class expression:
+		def __init__(self, expr):
+			self.expr = expr
+
+		def bc(self):
+			string = self.expr.bc()
+			return "${shell echo '" + string + "' | bc}"
+
+		def perl(self):
+			string = self.expr.perl()
+			return "${shell perl -e 'printf(\"%u\\n\", " + string + ");' }"
+	
+	# Tokens: ( ) ! | & + - * / << >> option )
+	start_re     = re.compile(r"^\s*(([A-Za-z_][A-Za-z_0-9]*)|((0x[0-9A-Za-z]+)|([0-9]+))|(\()|(!))(.*)$")
+	close_re     = re.compile(r"^\s*\)(.*)$")
+	middle_re    = re.compile(r"^\s*((\|)|(&)|(\+)|(-)|(\*)|(/)|(<<)|(>>))(.*)$")
+
+	def __init__(self, expr):
+		self.orig_expr = expr
+		self.expr = ""
+
+	def prec(self, op):
+		if (op == "|"):
+			result = 1
+		elif (op == "&"):
+			result = 2
+		elif (op == "+") or (op == "-"):
+			result = 3
+		elif (op == "*") or (op == "/"):
+			result = 4
+		elif (op == "<<") or (op == ">>"):
+			result = 5
+
+
+	def _parse_start(self):
+		#print("start expr: %s"%(self.expr))
+		m = self.start_re.match(self.expr)
+		if m:
+			(token, self.expr) = (m.group(1), m.group(8))
+			if token == "(":
+				left = self._parse()
+				#print("close expr: %s"%(self.expr))
+				m = self.close_re.match(self.expr)
+				if  m:
+					self.expr = m.group(1)
+				else:
+					fatal("No Matching )");
+			elif (token == "!"):
+				right = self._parse()
+				left = self.unary(token, right)
+			elif m.group(2):
+				if not makeoptions.has_key(token):
+					fatal("Option %s not defined" % token)
+				left = self.identifier(token)
+			elif m.group(3):
+				left = self.constant(token)
+		else: 
+			fatal("Invalid expression: %s" % self.expr)
+		return left
+
+	def _parse_middle(self, left):
+		#print("middle expr: %s"%(self.expr))
+		m = self.middle_re.match(self.expr)
+		while(m):
+			(op, self.expr) = (m.group(1),m.group(10))
+			right = self._parse_start()
+			m = self.middle_re.match(self.expr)
+			if m and (self.prec(op) < self.prec(m.group(1))):
+				right = self._parse_middle()
+			left = self.binary(op, left, right)
+		return left
+		
+	def _parse(self):
+		left = self._parse_start()
+		return self._parse_middle(left)
+
+	def parse(self):
+		self.expr = self.orig_expr
+		result = self._parse()
+		if self.expr != "":
+			fatal("Extra tokens: %s"% self.expr)
+		return self.expression(result)
+
 # Put "<option>:=<value>" and add <option> to VARIABLES in Makefile.settings
 def set_option(option, value):
-	if makenooptions.has_key(option):
-		del makenooptions[option]
-	makeoptions[option] = value
+	if makeoptions.has_key(option) and (makeoptions[option][0] == "expr"):
+		fatal("Cannot replace expression %s" % option)
+	makeoptions[option] = ("option", value)
 
 # Add <option> to VARIABLES in Makefile.settings
+# And remove any value <option> may already have.
 def clear_option(option):
-	if makeoptions.has_key(option):
-		del makeoptions[option]
-	makenooptions[option] = ""
+	if makeoptions.has_key(option) and (makeoptions[option][0] == "expr"):
+		fatal("Cannot clear expression %s" % option)
+	makeoptions[option] = ("nooption", "")
+
+# Put "<option>:=<value>" and add <option> to VARIABLES in Makefile.settings
+def set_expr(option, value):
+	if makeoptions.has_key(option) and (makeoptions[option][0] == "expr"):
+		fatal("Cannot replace expression %s" % option)
+	makeexpressions.append(option);
+	makeoptions[option] = ("expr", mkexpr(value).parse().perl())
+
 
 # COMMAND: option <option-name> [=<optional value>]
 #
@@ -451,7 +679,7 @@ def clear_option(option):
 # Also, put "<option>:=<value>" and add <option> to VARIABLES in
 # Makefile.settings
 #
-option_re = re.compile(r"^([^=]*)=(.*)$")
+option_re = re.compile(r"^([A-Za-z_][A-Za-z_0-9]+)\s*=(.*)$")
 def option(dir, option):
 	m = option_re.match(option)
 	key=option
@@ -461,10 +689,18 @@ def option(dir, option):
 	set_option(key, value)
 
 # COMMAND: nooption <option-name>
-# Add <option-namee> to VARIABLES and "-U<option-name>" to CFLAGS.
+# Add <option-name> to VARIABLES and "-U<option-name>" to CFLAGS.
 def nooption(dir, option):
 	clear_option(option)
 
+# COMMAND: expr
+def expr(dir, option):
+	m = option_re.match(option)
+	value= ""
+	if m and m.group(1):
+		(key, value) = m.groups()
+	set_expr(key, value)
+	
 # COMMAND: commandline <stuff>
 # Equivalent to "option CMD_LINE="<stuff>".
 def commandline(dir, command):
@@ -498,7 +734,8 @@ def payload(dir, payload_name):
 
 # COMMAND: linux <linux_dir>
 def linux(dir, linux_name):
-	payload(dir, linux_name + '/vmlinux')
+	linuxrule = 'LINUX=' + linux_name + '/vmlinux'
+	makedefine(dir, linuxrule)
 
 # COMMAND: rambase <address>
 def rambase(dir, address):
@@ -552,14 +789,15 @@ command_actions = {
 	'nooption'    : nooption,
 	'rambase'     : rambase,
 	'biosbase'    : biosbase,
-	'commandline' : commandline
+	'commandline' : commandline,
+	'expr'        : expr,
 	}
 
 # Open file, extract lines, and close.  For reading config and "base" files.
 def readfile(filename): 
 	if not os.path.isfile(filename):
 		print filename, "is not a file \n"
-		sys.exit()
+		sys.exit(1)
 	fileobject = open(filename, "r")
 	filelines = fileobject.readlines()
 	fileobject.close()
@@ -580,15 +818,13 @@ config_file_list = []
 
 # Process config files.
 def doconfigfile(dir, filename):
-	global current_command
-
 	if (debug):
 		print "doconfigfile" , filename
 
 	config_file_list.append(filename)
 
 	# Keep track of current config file, for error reporting.
-	config_file_stack.append(filename)
+	loc.push_file(filename)
 
 	if (debug):
 		print "doconfigfile: config_file_list ", config_file_list
@@ -597,7 +833,7 @@ def doconfigfile(dir, filename):
 		print "doconfigfile: filelines", filelines
 
 	for line in filelines:
-		current_command = line
+		loc.next_line(line)
 
 		(verb, args) = command_re.match(line).groups()
 		if not verb:
@@ -608,22 +844,21 @@ def doconfigfile(dir, filename):
 			# The commands above can accept comments as regular
 			# arguments.  For all other commands, strip
 			# final whitespace and comments.
-			args = stripcomment_re.match(args).group(1)
+			if args:
+				args = stripcomment_re.match(args).group(1)
 
 		if ((arch == '') and not verb in
 					('arch', 'mainboard', 'target')):
-			print "arch, target, or mainboard must be "
-			print "the first commands, not ", verb
-			sys.exit()
+			fatal("arch, target, or mainboard must be\n"
+				"the first commands, not %s"%(verb))
 
 		if command_actions.has_key(verb):
 			# Call the command execution function.
 			command_actions[verb](dir, args)
 		else:
-			print verb, "is not a valid command! \n"
-			sys.exit()
+			fatal("%s is not a valid command!"% (verb))
 
-	config_file_stack.pop()
+	loc.pop_file()
 
 
 # -----------------------------------------------------------------------------
@@ -708,12 +943,23 @@ def writemakefilesettings(path):
 	keys = makeoptions.keys()
 	keys.sort()
 	for key in keys:
-		file.write("export %s:=%s\n" % (key, makeoptions[key]))
+		(type, value) = makeoptions[key]
+		if type == "option":
+			file.write("export %s:=%s\n" % (key, value))
+	
+	# Write out the expressions in the order they were defined
+	# This ensures expressions that depend on other expressions
+	# will execute correctly
+	i = 0
+	while(i < len(makeexpressions)):
+		key = makeexpressions[i]
+		(type, value) = makeoptions[key]
+		file.write("export %s:=%s\n" % (key, value))
+		i = i + 1
+
 	file.write("export VARIABLES := ");
 	for key in keys:
 		file.write("%s " % key)
-	for key in makenooptions.keys(): 
-		file.write("%s " % (key))
 	file.write("\n");
 
 
@@ -804,8 +1050,8 @@ CPUFLAGS := $(foreach _var_,$(VARIABLES),$(call D_item,$(_var_)))
 	for mbifile in mainboardinit_files:
 		file.write("crt0.s: $(TOP)/src/%s\n" % mbifile[0])
 
-	# Print out the rules that will cause the files generated by
-	# NLBConfig.py to be remade if any dependencies change.
+	# Print out the rules that will make cause the files
+	# generated by NLBConfig.py to be remade if any dependencies change.
 	# It would seem sensible to write a rule with multiple targets, e.g.
 	# Makefile Makefile.settings crt0.S nsuperio.c: ...dependencies...
 	# but 'make' will run the rule for Makefile.settings (if out of date)
@@ -835,6 +1081,13 @@ CPUFLAGS := $(foreach _var_,$(VARIABLES),$(call D_item,$(_var_)))
 	file.write("\tpython $(TOP)/util/config/NLBConfig.py %s $(TOP)\n"
 			% top_config_file)
 
+	keys = makeoptions.keys()
+	keys.sort()
+	file.write("\necho:\n")
+	for key in keys:
+		file.write("\t@echo %s='$(%s)'\n"% (key,key))
+	
+
 	file.close();
 
 def writesuperiofile(path):
@@ -856,7 +1109,7 @@ def writesuperiofile(path):
 
 if len(sys.argv) != 3:
 	print "python NLBConfig.py <Config Filename> <src-path>\n"
-	sys.exit()
+	sys.exit(1)
 
 # Retrieve config filename from command line.
 top_config_file = os.path.abspath(sys.argv[1])