binman: Add a function to read ELF symbols

In some cases we need to read symbols from U-Boot. At present we have a
a few cases which does this via 'nm' and 'grep'.

It is better to use objdump since that tells us the size of the symbols
and also whether it is weak or not.

Add a new module which reads ELF information from files. Update existing
uses of 'nm' to use this module.

Signed-off-by: Simon Glass <sjg@chromium.org>

1 files changed, 4 insertions, 5 deletions

diff --git a/tools/binman/etype/u_boot_with_ucode_ptr.py b/tools/binman/etype/u_boot_with_ucode_ptr.py
index 6f01adb970..99b437130d 100644
--- a/tools/binman/etype/u_boot_with_ucode_ptr.py
+++ b/tools/binman/etype/u_boot_with_ucode_ptr.py
@@ -9,6 +9,7 @@
 import struct
 
 import command
+import elf
 from entry import Entry
 from blob import Entry_blob
 import fdt_util
@@ -31,11 +32,9 @@ class Entry_u_boot_with_ucode_ptr(Entry_blob):
     def ObtainContents(self):
         # Figure out where to put the microcode pointer
         fname = tools.GetInputFilename(self.elf_fname)
-        args = [['nm', fname], ['grep', '-w', '_dt_ucode_base_size']]
-        out = (command.RunPipe(args, capture=True, raise_on_error=False).
-               stdout.splitlines())
-        if len(out) == 1:
-            self.target_pos = int(out[0].split()[0], 16)
+        sym = elf.GetSymbolAddress(fname, '_dt_ucode_base_size')
+        if sym:
+           self.target_pos = sym
         elif not fdt_util.GetBool(self._node, 'optional-ucode'):
             self.Raise('Cannot locate _dt_ucode_base_size symbol in u-boot')