Allow rom to grow beyond 64K.

If rom is over 64K then use part of e-segment for 32bit code.
Push 32bit code as high as it can go in the f-segment.
Do version building before layoutrom.py - this way layoutrom knows
    full size of rom.
Make layoutrom.py build the full ld script - remove now unused ld
    scripts that just imported the output of layoutrom.py.
Also, use "objdump" instead of "nm" - reduce toolchain requirements.
Enhance tools/checkrom.py so that it can pad bios.bin to size qemu is
    happy with.
Also, add dependencies to build rules for local tools - if tool
    changes automatically rerun it.
Make sure option roms don't overwrite the 32bit code (should the 32bit
    code be in the e-segment).
Make sure shadow code works even if part of the code is in the
    e-segment.
diff --git a/tools/checkrom.py b/tools/checkrom.py
index 7dc5afc..b1d732a 100755
--- a/tools/checkrom.py
+++ b/tools/checkrom.py
@@ -6,33 +6,56 @@
 # This file may be distributed under the terms of the GNU GPLv3 license.
 
 import sys
+import layoutrom
 
 def main():
-    # Read in symbols (that are valid)
-    syms = {}
-    for line in sys.stdin.readlines():
-        try:
-            addr, type, sym = line.split()
-            syms[sym] = int(addr, 16)
-        except:
-            pass
+    # Get args
+    objinfo, rawfile, outfile = sys.argv[1:]
 
+    # Read in symbols
+    objinfofile = open(objinfo, 'rb')
+    symbols = layoutrom.parseObjDump(objinfofile)[1]
+    syms = {}
+    for name, (addr, section) in symbols.items():
+        syms[name] = addr
+
+    # Read in raw file
+    f = open(rawfile, 'rb')
+    rawdata = f.read()
+    f.close()
+    datasize = len(rawdata)
+    finalsize = 64*1024
+    if datasize > 64*1024:
+        finalsize = 128*1024
+
+    # Sanity checks
     c16e = syms['code16_end'] + 0xf0000
     f16e = syms['final_code16_end']
     if c16e != f16e:
         print "Error!  16bit code moved during linking (0x%x vs 0x%x)" % (
             c16e, f16e)
         sys.exit(1)
+    if datasize > finalsize:
+        print "Error!  Code is too big (0x%x vs 0x%x)" % (
+            datasize, finalsize)
+        sys.exit(1)
 
+    # Print statistics
     sizefree = syms['freespace_end'] - syms['freespace_start']
     size16 = syms['code16_end'] - syms['code16_start']
     size32 = syms['code32_end'] - syms['code32_start']
     totalc = size16+size32
     print "16bit size: %d" % size16
     print "32bit size: %d" % size32
-    print "Total size: %d  Free space: %d  Percent used: %.1f%%" % (
-        totalc, sizefree
-        , (totalc / float(size16+size32+sizefree)) * 100.0)
+    print "Total size: %d  Free space: %d  Percent used: %.1f%% (%dKiB rom)" % (
+        totalc, sizefree + finalsize - datasize
+        , (totalc / float(finalsize)) * 100.0
+        , finalsize / 1024)
+
+    # Write final file
+    f = open(outfile, 'wb')
+    f.write(("\0" * (finalsize - datasize)) + rawdata)
+    f.close()
 
 if __name__ == '__main__':
     main()