Hi, This series is an attempt to start discussion on the DT overlay build time support. Basically, one can build DT overlays directly from kernel tree, and also build FIT images that contain the kernel + devicetree blobs required for specific configuration that can be booted directly with u-boot. No runtime support for overlay switching is touched by this series. What this series does, is to: 1) add subdir support under arch/arm/boot/dts 2) provide DT overlay build support to kernel tree 3) provide FIT image build support to kernel tree 4) provide a number of DT overlay + FIT image files for some TI SoCs to show the reasons why we are doing this, this is only a subset of our boards that we would want to use overlays with Main reason for TI to use DT overlays right now is the rather large amount of different displays we have around, which can be used with different boards. With the current approach one needs to write a separate .dts file for each board + display config, but with overlays, one can just create a single overlay that would apply to different boards. There are some other cases like the shown dra71-evm case in this series, where the gpmc vs. display support is mutually exclusive, as they are sharing certain pieces of the HW. The main controversy with this series is most likely where the DT overlay files should be stored at. Should they still reside with the kernel tree or someplace else? Also, the FIT image support is probably controversial, should it be part of the kernel build system like shown here, or should it be separate? The zImage dependency is pretty annoying so maybe it should be done somewhere else. Any comments welcome as this is just an RFC for now, but basically we would really want a solution to this problem. -Tero -- Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki. Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
