Generating LMA for final.elf dynamically

SConstruct.loader

@@ -29,7 +29,7 @@ env = Environment(CC = 'arm-none-eabi-gcc',
 		  # such as stdarg.h e.g. for variable args, as in printk().
 		  CCFLAGS = ['-g', '-mcpu=arm926ej-s', '-nostdlib', '-ffreestanding', \
 			     '-std=gnu99', '-Wall', '-Werror'],
-		  LINKFLAGS = ['-nostdlib', '-T' + "loader/linker.lds", "-u_start"],
+		  LINKFLAGS = ['-nostdlib', '-T' + join(BUILDDIR, 'loader/linker.lds'), "-u_start"],
 		  ASFLAGS = ['-D__ASSEMBLY__'],
 		  PROGSUFFIX = '.elf',
 		  ENV = {'PATH' : os.environ['PATH']},

loader/SConscript

@@ -16,6 +16,45 @@ PROJRELROOT = '../../'
 
 from config.projpaths import *
 from scripts.loader.generate_loader_asm import *
+from config.lib import *
+
+# Function to determine the LMA for 'final.elf'
+def find_lma_codezero(target, source, env):
+    # Start/end addresses of various physical memory regions defined
+    array_start = []
+    array_end = []
+
+    with open(join(PROJROOT, CONFIG_H), 'r')as file:
+        for line in file:
+            begin = line.rfind(" ")
+            end = len(line)
+            if re.search("(PHYS)(.)(_START)", line):
+                array_start.append(int(line[begin : end], 16))
+            elif re.search("(PHYS)(.)(_END)", line):
+                array_end.append(int(line[begin : end], 16))
+    array_start.sort()
+    array_end.sort()
+
+    # Size of physical memory hole we need for 'final.elf' say 16MB
+    mem_needed = 0x1000000
+    # Default LMA = 32MB, if we have no container
+    loadaddr = 0x1000000
+    for index,end in enumerate(array_end):
+        loadaddr = end
+        if (index+1) >= len(array_start):
+            # Reached end of start_array
+            break
+        else:
+            start = array_start[index+1]
+        if start-end >= mem_needed:
+            break
+
+    # Create target file
+    with open(source[1].path, 'r') as input:
+        buffer = input.read()
+        print 'LMA FOR FINAL.ELF IS : ' + str(conv_hex(loadaddr))
+        with open(target[0].path, 'w+') as output:
+            output.write(buffer % str(conv_hex(loadaddr)))
 
 def ksym_to_loader(target, source, env):
     generate_ksym_to_loader(target[0].path, source[0].path)
@@ -26,10 +65,13 @@ def gen_loader_images_S(target, source, env):
 loader_ksyms = Command(join(PROJROOT, 'loader/ksyms.S'), join(BUILDDIR, 'kernel.elf'), ksym_to_loader)
 loader_image_S = Command(join(PROJROOT, 'loader/images.S'), [join(BUILDDIR, 'kernel.elf'), join(BUILDDIR, 'conts/containers.elf')], \
                          gen_loader_images_S)
-
+lma_lds = Command(join(BUILDDIR, 'loader/linker.lds'), \
+                  [join(BUILDDIR, 'kernel.elf'), \
+                   join(PROJROOT, 'loader/linker.lds.in')], find_lma_codezero)
 src = Glob('*.[cS]')
 objs = env.Object(src)
 
+Depends(src, lma_lds)
 Depends(src, loader_ksyms)
 Depends(src, loader_image_S)
 Depends(objs, join(BUILDDIR, 'conts/containers.elf'))

loader/linker.lds.in

@@ -3,11 +3,13 @@
  *
  * Copyright (C) 2008-2009 B Labs Ltd.
  */
+
+lma_codezero = %s;
 ENTRY(_start)
 
 SECTIONS
 {
-	. = 0x3000000;
+	. = lma_codezero;
 	.text : { *(.text.head) *(.text) }
 	.rodata : { *(.rodata) }
 	.rodata1 : { *(.rodata1) }