From c58299aa87544a590c62bda0bf52b69fa56cb8d5 Mon Sep 17 00:00:00 2001 From: Stephen Warren Date: Wed, 20 Feb 2013 13:39:41 -0700 Subject: [PATCH] kbuild: create an "include chroot" for DT bindings The recent dtc+cpp support allows header files and C pre-processor defines/macros to be used when compiling device tree files. These headers will typically define various constants that are part of the device tree bindings. The original patch which set up the dtc+cpp include path only considered using those headers from device tree files. However, most are also useful for kernel code which needs to interpret the device tree. In both the DT files and the kernel, I'd like to include the DT-related headers in the same way, for example, . That will simplify any text which discusses the DT header locations. Creating a for kernel source to use is as simple as placing files into include/dt-bindings/. However, when compiling DT files, the include path should be restricted so that only the dt-bindings path is available; arbitrary kernel headers shouldn't be exposed. For this reason, create a specific include directory for use by dtc+cpp, and symlink dt-bindings from there to the actual location of include/dt-bindings/. For want of a better location, place this "include chroot" into the existing dts/ directory. arch/*/boot/dts/include/dt-bindings -> ../../../../../include/dt-bindings Some headers used by device tree files may not be useful to the kernel; they may be used simply to aid in constructing the DT file (e.g. macros to create a node), but not define any information that the kernel needs to share. These may be placed directly into arch/*/boot/dts/ along with the DT files themselves. Acked-by: Michal Marek Acked-by: Shawn Guo Acked-by: Rob Herring Signed-off-by: Stephen Warren --- arch/arm/boot/dts/include/dt-bindings | 1 + scripts/Makefile.lib | 2 +- 2 files changed, 2 insertions(+), 1 deletion(-) create mode 120000 arch/arm/boot/dts/include/dt-bindings diff --git a/arch/arm/boot/dts/include/dt-bindings b/arch/arm/boot/dts/include/dt-bindings new file mode 120000 index 000000000000..08c00e4972fa --- /dev/null +++ b/arch/arm/boot/dts/include/dt-bindings @@ -0,0 +1 @@ +../../../../../include/dt-bindings \ No newline at end of file diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib index 07125e697d7a..af35521b00a4 100644 --- a/scripts/Makefile.lib +++ b/scripts/Makefile.lib @@ -158,7 +158,7 @@ ld_flags = $(LDFLAGS) $(ldflags-y) dtc_cpp_flags = -Wp,-MD,$(depfile) -nostdinc \ -I$(srctree)/arch/$(SRCARCH)/boot/dts \ - -I$(srctree)/arch/$(SRCARCH)/include/dts \ + -I$(srctree)/arch/$(SRCARCH)/boot/dts/include \ -undef -D__DTS__ # Finds the multi-part object the current object will be linked into -- 2.39.5