Don't relocate "varlow" variable references at runtime.
Since the final location of the "varlow" variables are known at build
time, link the final locations into the binary during the build. The
16bit code was already done at link time - update the build so the
32bit code is also done at link time.
Signed-off-by: Kevin O'Connor <kevin@koconnor.net>
diff --git a/tools/layoutrom.py b/tools/layoutrom.py
index 2543c58..70370e4 100755
--- a/tools/layoutrom.py
+++ b/tools/layoutrom.py
@@ -152,6 +152,7 @@
# The sections (and associated information) to be placed in output rom
class LayoutInfo:
+ genreloc = None
sections16 = sec16_start = sec16_align = None
sections32seg = sec32seg_start = sec32seg_align = None
sections32flat = sec32flat_start = sec32flat_align = None
@@ -159,9 +160,10 @@
sections32low = sec32low_start = sec32low_align = None
sections32fseg = sec32fseg_start = sec32fseg_align = None
zonelow_base = final_sec32low_start = None
+ exportsyms = varlowsyms = None
# Determine final memory addresses for sections
-def doLayout(sections, genreloc):
+def doLayout(sections):
li = LayoutInfo()
# Determine 16bit positions
li.sections16 = getSectionsCategory(sections, '16')
@@ -223,17 +225,13 @@
# Determine "low memory" data positions
li.sections32low = getSectionsCategory(sections, '32low')
- if genreloc:
- sec32low_top = li.sec32init_start
- final_sec32low_top = min(BUILD_BIOS_ADDR, li.sec32flat_start)
- else:
- sec32low_top = min(BUILD_BIOS_ADDR, li.sec32init_start)
- final_sec32low_top = sec32low_top
- relocdelta = final_sec32low_top - sec32low_top
- zonelow_base = final_sec32low_top - 64*1024
+ sec32low_end = li.sec32init_start
+ final_sec32low_start = min(BUILD_BIOS_ADDR, li.sec32flat_start)
+ relocdelta = final_sec32low_start - sec32low_end
+ zonelow_base = final_sec32low_start - 64*1024
li.zonelow_base = max(BUILD_ROM_START, alignpos(zonelow_base, 2*1024))
li.sec32low_start, li.sec32low_align = setSectionsStart(
- li.sections32low, sec32low_top, 16
+ li.sections32low, sec32low_end, 16
, segoffset=li.zonelow_base - relocdelta)
li.final_sec32low_start = li.sec32low_start + relocdelta
@@ -243,7 +241,7 @@
size32fseg = li.sec32seg_start - li.sec32fseg_start
size32flat = li.sec32fseg_start - li.sec32flat_start
size32init = li.sec32flat_start - li.sec32init_start
- sizelow = sec32low_top - li.sec32low_start
+ sizelow = sec32low_end - li.sec32low_start
print "16bit size: %d" % size16
print "32bit segmented size: %d" % size32seg
print "32bit flat size: %d" % size32flat
@@ -258,7 +256,7 @@
######################################################################
# Write LD script includes for the given cross references
-def outXRefs(sections, useseg=0, exportsyms=[]):
+def outXRefs(sections, useseg=0, exportsyms=[], forcedelta=0):
xrefs = dict([(symbol.name, symbol) for symbol in exportsyms])
out = ""
for section in sections:
@@ -272,7 +270,7 @@
loc = symbol.section.finalloc
if useseg:
loc = symbol.section.finalsegloc
- out += "%s = 0x%x ;\n" % (symbolname, loc + symbol.offset)
+ out += "%s = 0x%x ;\n" % (symbolname, loc + forcedelta + symbol.offset)
return out
# Write LD script includes for the given sections using relative offsets
@@ -319,7 +317,7 @@
if section.finalloc is not None] or [defaddr])
# Output the linker scripts for all required sections.
-def writeLinkerScripts(li, exportsyms, genreloc, out16, out32seg, out32flat):
+def writeLinkerScripts(li, out16, out32seg, out32flat):
# Write 16bit linker script
out = outXRefs(li.sections16, useseg=1) + """
zonelow_base = 0x%x ;
@@ -350,11 +348,10 @@
outfile.close()
# Write 32flat linker script
- sections32all = (li.sections32flat + li.sections32init + li.sections32low
- + li.sections32fseg)
+ sections32all = (li.sections32flat + li.sections32init + li.sections32fseg)
sec32all_start = li.sec32low_start
relocstr = ""
- if genreloc:
+ if li.genreloc:
# Generate relocations
absrelocs = getRelocs(
li.sections32init, type='R_386_32', category='32init')
@@ -363,14 +360,14 @@
initrelocs = getRelocs(
li.sections32flat + li.sections32low + li.sections16
+ li.sections32seg + li.sections32fseg, category='32init')
- lowrelocs = getRelocs(sections32all, category='32low')
relocstr = (strRelocs("_reloc_abs", "code32init_start", absrelocs)
+ strRelocs("_reloc_rel", "code32init_start", relrelocs)
- + strRelocs("_reloc_init", "code32flat_start", initrelocs)
- + strRelocs("_reloc_varlow", "code32flat_start", lowrelocs))
- numrelocs = len(absrelocs + relrelocs + initrelocs + lowrelocs)
+ + strRelocs("_reloc_init", "code32flat_start", initrelocs))
+ numrelocs = len(absrelocs + relrelocs + initrelocs)
sec32all_start -= numrelocs * 4
- out = outXRefs(sections32all, exportsyms=exportsyms) + """
+ out = outXRefs(li.sections32low, exportsyms=li.varlowsyms
+ , forcedelta=li.final_sec32low_start-li.sec32low_start)
+ out += outXRefs(sections32all, exportsyms=li.exportsyms) + """
_reloc_min_align = 0x%x ;
zonelow_base = 0x%x ;
final_varlow_start = 0x%x ;
@@ -621,7 +618,12 @@
sections = gc(info16, info32seg, info32flat)
# Separate 32bit flat into runtime and init parts
- findInit(sections)
+ genreloc = '_reloc_abs_start' in info32flat[1]
+ if genreloc:
+ findInit(sections)
+ else:
+ for section in sections:
+ section.category = section.fileid
# Note "low memory" and "fseg memory" parts
for section in getSectionsPrefix(sections, '.data.varlow.'):
@@ -630,17 +632,22 @@
section.category = '32fseg'
# Determine the final memory locations of each kept section.
- genreloc = '_reloc_abs_start' in info32flat[1]
- li = doLayout(sections, genreloc)
+ li = doLayout(sections)
+ li.genreloc = genreloc
# Exported symbols
- exportsyms = [symbol for symbol in info16[1].values()
- if (symbol.section is not None
- and '.export.' in symbol.section.name
- and symbol.name != symbol.section.name)]
+ li.exportsyms = [symbol for symbol in info16[1].values()
+ if (symbol.section is not None
+ and '.export.' in symbol.section.name
+ and symbol.name != symbol.section.name)]
+ li.varlowsyms = [symbol for symbol in info32flat[1].values()
+ if (symbol.section is not None
+ and symbol.section.finalloc is not None
+ and '.data.varlow.' in symbol.section.name
+ and symbol.name != symbol.section.name)]
# Write out linker script files.
- writeLinkerScripts(li, exportsyms, genreloc, out16, out32seg, out32flat)
+ writeLinkerScripts(li, out16, out32seg, out32flat)
if __name__ == '__main__':
main()