binman: Allow entry types to override FDT contents

At present the contents of an FDT (for each phase) are fixed,
determined by the build and provided to Binman as input files.

Provide a means for entry types to provide their own FDT, so that it can
be processed, if needed.

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

3 files changed, 18 insertions, 2 deletions

diff --git a/tools/binman/entry.py b/tools/binman/entry.py
index 752c584c9a3..494b1b1278d 100644
--- a/tools/binman/entry.py
+++ b/tools/binman/entry.py
@@ -1386,3 +1386,15 @@ features to produce new behaviours.
 
     def UpdateSignatures(self, privatekey_fname, algo, input_fname):
         self.Raise('Updating signatures is not supported with this entry type')
+
+    def FdtContents(self, fdt_etype):
+        """Get the contents of an FDT for a particular phase
+
+        Args:
+            fdt_etype (str): Filename of the phase of the FDT to return, e.g.
+                'u-boot-tpl-dtb'
+
+        Returns:
+            bytes: Contents of requested FDT
+        """
+        return self.section.FdtContents(fdt_etype)
diff --git a/tools/binman/etype/blob_dtb.py b/tools/binman/etype/blob_dtb.py
index 1471ded2211..b234323d7cf 100644
--- a/tools/binman/etype/blob_dtb.py
+++ b/tools/binman/etype/blob_dtb.py
@@ -41,12 +41,12 @@ class Entry_blob_dtb(Entry_blob):
     def ObtainContents(self, fake_size=0):
         """Get the device-tree from the list held by the 'state' module"""
         self._filename = self.GetDefaultFilename()
-        self._pathname, _ = state.GetFdtContents(self.GetFdtEtype())
+        self._pathname, _ = self.FdtContents(self.GetFdtEtype())
         return super().ReadBlobContents()
 
     def ProcessContents(self):
         """Re-read the DTB contents so that we get any calculated properties"""
-        _, indata = state.GetFdtContents(self.GetFdtEtype())
+        _, indata = self.FdtContents(self.GetFdtEtype())
 
         if self.compress == 'zstd' and self.prepend != 'length':
             self.Raise('The zstd compression requires a length header')
diff --git a/tools/binman/image.py b/tools/binman/image.py
index 97443d3c0a7..c1be5cc23a2 100644
--- a/tools/binman/image.py
+++ b/tools/binman/image.py
@@ -425,3 +425,7 @@ class Image(section.Entry_section):
         super().AddBintools(bintools)
         self.bintools = bintools
         return bintools
+
+    def FdtContents(self, fdt_etype):
+        """This base-class implementation simply calls the state function"""
+        return state.GetFdtContents(fdt_etype)