binman: Add support for ATF BL31

Add an entry for ARM Trusted Firmware's 'BL31' payload, which is the
device's main firmware. Typically this is U-Boot.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/tools/binman/README.entries b/tools/binman/README.entries
index 1086a6a..8999d5e 100644
--- a/tools/binman/README.entries
+++ b/tools/binman/README.entries
@@ -11,6 +11,20 @@
 
 
 
+Entry: atf-bl31: Entry containing an ARM Trusted Firmware (ATF) BL31 blob
+-------------------------------------------------------------------------
+
+Properties / Entry arguments:
+    - atf-bl31-path: Filename of file to read into entry. This is typically
+        called bl31.bin or bl31.elf
+
+This entry holds the run-time firmware, typically started by U-Boot SPL.
+See the U-Boot README for your architecture or board for how to use it. See
+https://github.com/ARM-software/arm-trusted-firmware for more information
+about ATF.
+
+
+
 Entry: blob: Entry containing an arbitrary binary blob
 ------------------------------------------------------
 
diff --git a/tools/binman/etype/atf_bl31.py b/tools/binman/etype/atf_bl31.py
new file mode 100644
index 0000000..195adc7
--- /dev/null
+++ b/tools/binman/etype/atf_bl31.py
@@ -0,0 +1,24 @@
+# SPDX-License-Identifier: GPL-2.0+
+# Copyright 2020 Google LLC
+# Written by Simon Glass <sjg@chromium.org>
+#
+# Entry-type module for Intel Management Engine binary blob
+#
+
+from binman.etype.blob_named_by_arg import Entry_blob_named_by_arg
+
+class Entry_atf_bl31(Entry_blob_named_by_arg):
+    """Entry containing an ARM Trusted Firmware (ATF) BL31 blob
+
+    Properties / Entry arguments:
+        - atf-bl31-path: Filename of file to read into entry. This is typically
+            called bl31.bin or bl31.elf
+
+    This entry holds the run-time firmware, typically started by U-Boot SPL.
+    See the U-Boot README for your architecture or board for how to use it. See
+    https://github.com/ARM-software/arm-trusted-firmware for more information
+    about ATF.
+    """
+    def __init__(self, section, etype, node):
+        super().__init__(section, etype, node, 'atf-bl31')
+        self.external = True
diff --git a/tools/binman/ftest.py b/tools/binman/ftest.py
index ceeee1d..2b3690e 100644
--- a/tools/binman/ftest.py
+++ b/tools/binman/ftest.py
@@ -74,6 +74,7 @@
 FSP_M_DATA            = b'fsp_m'
 FSP_S_DATA            = b'fsp_s'
 FSP_T_DATA            = b'fsp_t'
+ATF_BL31_DATA         = b'bl31'
 
 # The expected size for the device tree in some tests
 EXTRACT_DTB_SIZE = 0x3c9
@@ -167,6 +168,7 @@
                         os.path.join(cls._indir, 'files'))
 
         TestFunctional._MakeInputFile('compress', COMPRESS_DATA)
+        TestFunctional._MakeInputFile('bl31.bin', ATF_BL31_DATA)
 
         # Travis-CI may have an old lz4
         cls.have_lz4 = True
@@ -3550,5 +3552,12 @@
         self.assertIn("Missing required properties/entry args: cros-ec-rw-path",
                       str(e.exception))
 
+    def testPackBl31(self):
+        """Test that an image with an ATF BL31 binary can be created"""
+        data = self._DoReadFile('169_atf_bl31.dts')
+        self.assertEqual(ATF_BL31_DATA, data[:len(ATF_BL31_DATA)])
+
+ATF_BL31_DATA
+
 if __name__ == "__main__":
     unittest.main()
diff --git a/tools/binman/test/169_atf_bl31.dts b/tools/binman/test/169_atf_bl31.dts
new file mode 100644
index 0000000..2b7547d
--- /dev/null
+++ b/tools/binman/test/169_atf_bl31.dts
@@ -0,0 +1,16 @@
+// SPDX-License-Identifier: GPL-2.0+
+
+/dts-v1/;
+
+/ {
+	#address-cells = <1>;
+	#size-cells = <1>;
+
+	binman {
+		size = <16>;
+
+		atf-bl31 {
+			filename = "bl31.bin";
+		};
+	};
+};