On 03/05/2013 11:55 PM, Rob Herring wrote: > On 03/05/2013 12:06 PM, Stephen Warren wrote: >> From: Stephen Warren <swarren@xxxxxxxxxx> >> >> 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, <dt-bindings/gpio/tegra-gpio.h>. >> That will simplify any text which discusses the DT header locations. >> >> Creating a <dt-bindings/> 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. >> >> Cc: Hiroshi Doyu <hdoyu@xxxxxxxxxx> >> Acked-by: Michal Marek <mmarek@xxxxxxx> >> Acked-by: Shawn Guo <shawn.guo@xxxxxxxxxx> >> Signed-off-by: Stephen Warren <swarren@xxxxxxxxxx> >> --- >> Grant, Rob, >> >> This is a pre-requisite for people to convert their *.dts files to use >> cpp, and hence is likely to be useful for a number of ARM subarch trees. >> Perhaps this patch can be placed into a standalone topic branch in the >> DT repo so we can all merge it. Assuming this patch is OK, I would also >> repost the patches that create common headers defining IRQ, and GPIO >> flags, which would place files into the new include/dt-bindings >> directory. > > This looks fine to me. As all these will all be arm-soc branches with > the dependency, it probably makes more sense for Arnd/Olof to apply this > and create the branch for this single patch. OK, that'd work fine for me too. I expect that arm-soc branch would also include the few patches to create some common headers, once I repost. -- To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
