fdt: Make it easier to debug u-boot.dtsi files

At present one must hack the Makefile to see what is going on with these
files. Also it doesn't quite work correctly.

Fix this by using an environment variable for debugging. Update the docs
also.

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

diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
index 39f0339..b4e63bc 100644 (file)
--- a/scripts/Makefile.lib
+++ b/scripts/Makefile.lib
@@ -175,7 +175,9 @@ u_boot_dtsi_options_raw = $(warning Automatic .dtsi inclusion: options: \
 
 # Uncomment for debugging
 # This shows all the files that were considered and the one that we chose.
-# u_boot_dtsi_options_debug = $(u_boot_dtsi_options_raw)
+ifdef DEVICE_TREE_DEBUG
+u_boot_dtsi_options_debug = $(warning $(u_boot_dtsi_options_raw))
+endif
 
 # We use the first match
 u_boot_dtsi = $(strip $(u_boot_dtsi_options_debug) \

diff --git a/tools/binman/binman.rst b/tools/binman/binman.rst
index 56f8658..3e063d1 100644 (file)
--- a/tools/binman/binman.rst
+++ b/tools/binman/binman.rst
@@ -790,12 +790,14 @@ Binman will search for the following files in arch/<arch>/dts::
 
 U-Boot will only use the first one that it finds. If you need to include a
 more general file you can do that from the more specific file using #include.
-If you are having trouble figuring out what is going on, you can uncomment
-the 'warning' line in scripts/Makefile.lib to see what it has found::
-
-   # Uncomment for debugging
-   # This shows all the files that were considered and the one that we chose.
-   # u_boot_dtsi_options_debug = $(u_boot_dtsi_options_raw)
+If you are having trouble figuring out what is going on, you can use
+`DEVICE_TREE_DEBUG=1` with your build::
+
+   make DEVICE_TREE_DEBUG=1
+   scripts/Makefile.lib:334: Automatic .dtsi inclusion: options:
+     arch/arm/dts/juno-r2-u-boot.dtsi arch/arm/dts/-u-boot.dtsi
+     arch/arm/dts/armv8-u-boot.dtsi arch/arm/dts/armltd-u-boot.dtsi
+     arch/arm/dts/u-boot.dtsi ... found: "arch/arm/dts/juno-r2-u-boot.dtsi"
 
 
 Updating an ELF file