diff --git a/tools/binman/state.py b/tools/binman/state.py
index 053b4fe73f..84f606b188 100644
--- a/tools/binman/state.py
+++ b/tools/binman/state.py
@@ -188,17 +188,16 @@ def Prepare(images, dtb):
             output_fdt_info[etype] = [dtb, fname]
     else:
         fdt_set = {}
-        for image in images.values():
-            fdt_set.update(image.GetFdts())
-        for etype, other in fdt_set.items():
-            entry, fname = other
-            infile = tools.GetInputFilename(fname)
-            fname_dtb = fdt_util.EnsureCompiled(infile)
-            out_fname = tools.GetOutputFilename('%s.out' %
-                    os.path.split(fname)[1])
-            tools.WriteFile(out_fname, tools.ReadFile(fname_dtb))
-            other_dtb = fdt.FdtScan(out_fname)
-            output_fdt_info[etype] = [other_dtb, out_fname]
+        for etype, fname in DTB_TYPE_FNAME.items():
+            infile = tools.GetInputFilename(fname, allow_missing=True)
+            if infile and os.path.exists(infile):
+                fname_dtb = fdt_util.EnsureCompiled(infile)
+                out_fname = tools.GetOutputFilename('%s.out' %
+                        os.path.split(fname)[1])
+                tools.WriteFile(out_fname, tools.ReadFile(fname_dtb))
+                other_dtb = fdt.FdtScan(out_fname)
+                output_fdt_info[etype] = [other_dtb, out_fname]
+
 
 def PrepareFromLoadedData(image):
     """Get device tree files ready for use with a loaded image
diff --git a/tools/patman/tools.py b/tools/patman/tools.py
index 10997e4386..e5f391b7aa 100644
--- a/tools/patman/tools.py
+++ b/tools/patman/tools.py
@@ -130,8 +130,12 @@ def GetInputFilename(fname, allow_missing=False):
         allow_missing: True if the filename can be missing
 
     Returns:
-        The full path of the filename, within the input directory, or
-        None on error
+        fname, if indir is None;
+        full path of the filename, within the input directory;
+        None, if file is missing and allow_missing is True
+
+    Raises:
+        ValueError if file is missing and allow_missing is False
     """
     if not indir or fname[:1] == '/':
         return fname