binman: Add support for a cros_ec image

Add an entry type which can hold a Chrome OS EC.

To make this work a new entry type is created, which supports getting a
blob filename from the command line.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/tools/binman/README.entries b/tools/binman/README.entries
index 0b3be69..147dd40 100644
--- a/tools/binman/README.entries
+++ b/tools/binman/README.entries
@@ -26,6 +26,35 @@
 
 
 
+Entry: blob-named-by-arg: A blob entry which gets its filename property from its subclass
+-----------------------------------------------------------------------------------------
+
+Properties / Entry arguments:
+    - <xxx>-path: Filename containing the contents of this entry (optional,
+        defaults to 0)
+
+where <xxx> is the blob_fname argument to the constructor.
+
+This entry cannot be used directly. Instead, it is used as a parent class
+for another entry, which defined blob_fname. This parameter is used to
+set the entry-arg or property containing the filename. The entry-arg or
+property is in turn used to set the actual filename.
+
+See cros_ec_rw for an example of this.
+
+
+
+Entry: cros-ec-rw: A blob entry which contains a Chromium OS read-write EC image
+--------------------------------------------------------------------------------
+
+Properties / Entry arguments:
+    - cros-ec-rw-path: Filename containing the EC image
+
+This entry holds a Chromium OS EC (embedded controller) image, for use in
+updating the EC on startup via software sync.
+
+
+
 Entry: fmap: An entry which contains an Fmap section
 ----------------------------------------------------
 
diff --git a/tools/binman/etype/blob_named_by_arg.py b/tools/binman/etype/blob_named_by_arg.py
new file mode 100644
index 0000000..344112b
--- /dev/null
+++ b/tools/binman/etype/blob_named_by_arg.py
@@ -0,0 +1,34 @@
+# SPDX-License-Identifier: GPL-2.0+
+# Copyright (c) 2018 Google, Inc
+# Written by Simon Glass <sjg@chromium.org>
+#
+# Entry-type module for a blob where the filename comes from a property in the
+# node or an entry argument. The property is called '<blob_fname>-path' where
+# <blob_fname> is provided by the subclass using this entry type.
+
+from collections import OrderedDict
+
+from blob import Entry_blob
+from entry import EntryArg
+
+
+class Entry_blob_named_by_arg(Entry_blob):
+    """A blob entry which gets its filename property from its subclass
+
+    Properties / Entry arguments:
+        - <xxx>-path: Filename containing the contents of this entry (optional,
+            defaults to 0)
+
+    where <xxx> is the blob_fname argument to the constructor.
+
+    This entry cannot be used directly. Instead, it is used as a parent class
+    for another entry, which defined blob_fname. This parameter is used to
+    set the entry-arg or property containing the filename. The entry-arg or
+    property is in turn used to set the actual filename.
+
+    See cros_ec_rw for an example of this.
+    """
+    def __init__(self, section, etype, node, blob_fname):
+        Entry_blob.__init__(self, section, etype, node)
+        self._filename, = self.GetEntryArgsOrProps(
+            [EntryArg('%s-path' % blob_fname, str)])
diff --git a/tools/binman/etype/cros_ec_rw.py b/tools/binman/etype/cros_ec_rw.py
new file mode 100644
index 0000000..261f865
--- /dev/null
+++ b/tools/binman/etype/cros_ec_rw.py
@@ -0,0 +1,22 @@
+# SPDX-License-Identifier: GPL-2.0+
+# Copyright (c) 2018 Google, Inc
+# Written by Simon Glass <sjg@chromium.org>
+#
+# Entry-type module for a Chromium OS EC image (read-write section)
+#
+
+from blob_named_by_arg import Entry_blob_named_by_arg
+
+
+class Entry_cros_ec_rw(Entry_blob_named_by_arg):
+    """A blob entry which contains a Chromium OS read-write EC image
+
+    Properties / Entry arguments:
+        - cros-ec-rw-path: Filename containing the EC image
+
+    This entry holds a Chromium OS EC (embedded controller) image, for use in
+    updating the EC on startup via software sync.
+    """
+    def __init__(self, section, etype, node):
+        Entry_blob_named_by_arg.__init__(self, section, etype, node,
+                                         'cros-ec-rw')
diff --git a/tools/binman/ftest.py b/tools/binman/ftest.py
index bd4de4e..5428ee6 100644
--- a/tools/binman/ftest.py
+++ b/tools/binman/ftest.py
@@ -46,6 +46,8 @@
 TEXT_DATA             = 'text'
 TEXT_DATA2            = 'text2'
 TEXT_DATA3            = 'text3'
+CROS_EC_RW_DATA       = 'ecrw'
+
 
 class TestFunctional(unittest.TestCase):
     """Functional tests for binman
@@ -92,6 +94,7 @@
         TestFunctional._MakeInputFile('cmc.bin', CMC_DATA)
         TestFunctional._MakeInputFile('vbt.bin', VBT_DATA)
         TestFunctional._MakeInputFile('mrc.bin', MRC_DATA)
+        TestFunctional._MakeInputFile('ecrw.bin', CROS_EC_RW_DATA)
         self._output_setup = False
 
         # ELF file with a '_dt_ucode_base_size' symbol
@@ -1224,6 +1227,14 @@
                          fmap_util.FMAP_AREA_LEN * 3, fentries[2].size)
         self.assertEqual('FMAP', fentries[2].name)
 
+    def testBlobNamedByArg(self):
+        """Test we can add a blob with the filename coming from an entry arg"""
+        entry_args = {
+            'cros-ec-rw-path': 'ecrw.bin',
+        }
+        data, _, _, _ = self._DoReadFileDtb('68_blob_named_by_arg.dts',
+                                            entry_args=entry_args)
+
 
 if __name__ == "__main__":
     unittest.main()
diff --git a/tools/binman/test/68_blob_named_by_arg.dts b/tools/binman/test/68_blob_named_by_arg.dts
new file mode 100644
index 0000000..e129f84
--- /dev/null
+++ b/tools/binman/test/68_blob_named_by_arg.dts
@@ -0,0 +1,12 @@
+// SPDX-License-Identifier: GPL-2.0+
+/dts-v1/;
+
+/ {
+	#address-cells = <1>;
+	#size-cells = <1>;
+
+	binman {
+		cros-ec-rw {
+		};
+	};
+};