binman: Add support for adding TPL binaries

Add support for U-Boot's TPL and TPL device tree. Also fix a few comments
in the other device-tree entries.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/tools/binman/README.entries b/tools/binman/README.entries
index 1b75ca0..c6e7b22 100644
--- a/tools/binman/README.entries
+++ b/tools/binman/README.entries
@@ -365,7 +365,7 @@
 binary which loads before U-Boot proper, typically into on-chip SRAM. It is
 responsible for locating, loading and jumping to U-Boot. Note that SPL is
 not relocatable so must be loaded to the correct address in SRAM, or written
-to run from the correct address is direct flash execution is possible (e.g.
+to run from the correct address if direct flash execution is possible (e.g.
 on x86 devices).
 
 SPL can access binman symbols at runtime. See:
@@ -433,6 +433,42 @@
 
 
 
+Entry: u-boot-tpl: U-Boot TPL binary
+------------------------------------
+
+Properties / Entry arguments:
+    - filename: Filename of u-boot-tpl.bin (default 'tpl/u-boot-tpl.bin')
+
+This is the U-Boot TPL (Tertiary Program Loader) binary. This is a small
+binary which loads before SPL, typically into on-chip SRAM. It is
+responsible for locating, loading and jumping to SPL, the next-stage
+loader. Note that SPL is not relocatable so must be loaded to the correct
+address in SRAM, or written to run from the correct address if direct
+flash execution is possible (e.g. on x86 devices).
+
+SPL can access binman symbols at runtime. See:
+
+    'Access to binman entry offsets at run time (symbols)'
+
+in the binman README for more information.
+
+The ELF file 'tpl/u-boot-tpl' must also be available for this to work, since
+binman uses that to look up symbols to write into the TPL binary.
+
+
+
+Entry: u-boot-tpl-dtb: U-Boot TPL device tree
+---------------------------------------------
+
+Properties / Entry arguments:
+    - filename: Filename of u-boot.dtb (default 'tpl/u-boot-tpl.dtb')
+
+This is the TPL device tree, containing configuration information for
+TPL. TPL needs this to know what devices are present and which drivers
+to activate.
+
+
+
 Entry: u-boot-ucode: U-Boot microcode block
 -------------------------------------------