Layout fixed area using linker instead of assembler.

The fixed offset requirements of the 16bit code can be done using
    multiple sections and a linker script.  Using the linker allows
    for more flexibility.
Also, have the 16bit code generate sections for every function and
    variable definition.

2 files changed, 76 insertions, 11 deletions

diff --git a/tools/checkrom.py b/tools/checkrom.py
index 7ba4d0d..6b5f1e9 100755
--- a/tools/checkrom.py
+++ b/tools/checkrom.py
@@ -19,22 +19,19 @@ def main():
 
     c16s = syms['code16_start'] + 0xf0000
     c32s = syms['final_code16_start']
-    f16s = syms['code16_fixed_start'] + 0xf0000
-    f32s = syms['final_code16_fixed_start']
-    if c16s != c32s or f16s != f32s:
-        print ("Error!  16bit code moved during linking"
-               " (0x%x vs 0x%x, 0x%x vs 0x%x)" % (
-                c32s, c16s, f16s, f32s))
+    if c16s != c32s:
+        print "Error!  16bit code moved during linking (0x%x vs 0x%x)" % (
+            c32s, c16s)
         sys.exit(1)
 
-    size16 = syms['code16_end'] - syms['code16_start']
+    sizefree = syms['freespace1_end'] - syms['freespace1_start']
+    size16 = syms['code16_end'] - syms['code16_start'] - sizefree
     size32 = syms['code32_end'] - syms['code32_start']
     totalc = size16+size32
-    sizefree = syms['freespace1_end'] - syms['freespace1_start']
     tablefree = syms['freespace2_end'] - syms['freespace2_start']
-    print "16bit C-code size: %d" % size16
-    print "32bit C-code size: %d" % size32
-    print "Total C-code size: %d  Free space: %d  Percent used: %.1f%%" % (
+    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 "BIOS table space:  %d" % tablefree
diff --git a/tools/layoutrom.py b/tools/layoutrom.py
new file mode 100755
index 0000000..f1fe0e1
--- /dev/null
+++ b/tools/layoutrom.py
@@ -0,0 +1,68 @@
+#!/usr/bin/env python
+# Script to arrange sections to ensure fixed offsets.
+#
+# Copyright (C) 2008  Kevin O'Connor <kevin@koconnor.net>
+#
+# This file may be distributed under the terms of the GNU GPLv3 license.
+
+import sys
+
+def main():
+    # Read in section names and sizes
+
+    # sections = [(idx, name, size, align), ...]
+    sections = []
+    for line in sys.stdin.readlines():
+        try:
+            idx, name, size, vma, lma, fileoff, align = line.split()
+            if align[:3] != '2**':
+                continue
+            sections.append((
+                int(idx), name, int(size, 16), int(align[3:])))
+        except:
+            pass
+
+    # fixedsections = [(addr, sectioninfo), ...]
+    fixedsections = []
+    textsections = []
+    rodatasections = []
+    datasections = []
+
+    # Find desired sections.
+    for section in sections:
+        name = section[1]
+        if name[:11] == '.fixedaddr.':
+            addr = int(name[11:], 16)
+            fixedsections.append((addr, section))
+        if name[:6] == '.text.':
+            textsections.append(section)
+        if name[:17] == '.rodata.__func__.' or name == '.rodata.str1.1':
+            rodatasections.append(section)
+        if name[:8] == '.data16.':
+            datasections.append(section)
+
+    # Write regular sections
+    for section in textsections:
+        name = section[1]
+        sys.stdout.write("*(%s)\n" % (name,))
+    sys.stdout.write("code16_rodata = . ;\n")
+    for section in rodatasections:
+        name = section[1]
+        sys.stdout.write("*(%s)\n" % (name,))
+    for section in datasections:
+        name = section[1]
+        sys.stdout.write("*(%s)\n" % (name,))
+
+    # Write fixed sections
+    sys.stdout.write("freespace1_start = . ;\n")
+    first = 1
+    for addr, section in fixedsections:
+        name = section[1]
+        sys.stdout.write(". = ( 0x%x - code16_start ) ;\n" % (addr,))
+        if first:
+            first = 0
+            sys.stdout.write("freespace1_end = . ;\n")
+        sys.stdout.write("*(%s)\n" % (name,))
+
+if __name__ == '__main__':
+    main()