On Sun, Sep 29, 2024 at 6:55 PM Marek Vasut <ma...@denx.de> wrote: > > On 9/28/24 12:47 AM, Lothar Rubusch wrote: > > [...] > > >>> Ideally I like to setup some Kconfig choice for base board selection > >>> and one for boot-mode. > >> > >>> 1.) In the documentation control.rst I read that the u-boot.dts is > >>> combined of several elements. Is there a way to take this base .dts, > >>> then add a base board .dtsi by Kconfig option, and similar a > >>> boot-mode? > >> > >> The -u-boot.dtsi is preprocessed by C preprocessor, just like all the > >> other DTs, so you can have a -u-boot.dtsi file which contains C > >> preprocessor conditional statements in it to conditionally include other > >> .dtsi files: > >> > >> #if IS_ENABLED(...) > >> #include ... > >> #else ... > >> ... > >> #endif > > > > Going through the include list setup by the Makefile made me find my > > mistake. Currently I may use u-boot specific stuff in arch/arm/dts and > > include generic .dtsi fragments from dts/upstream. Note: I'm not > > setting CONFIG_OF_UPSTREAM since I'm using the regular include list > > which already contains dts/upstream/src/arm/intel. Is this ok? Or, > > shall I try a different approach, which involves having > > CONFIG_OF_UPSTREAM explicitely set in the defconfig? > > I'm not quite sure I understand the question. Once this platform DTs > land in mainline and the DTs get synchronized into U-Boot, you should > then set CONFIG_OF_UPSTREAM. Until then, you could patch the DTs into > dts/upstream/ to test the result with OF_UPSTREAM enabled . >
Ah, sorry. I did not explain well. Currently I patch the DTs which should go to kernel/mainline into my local u-boot: dts/upstream/src/arm/intel/socfpga/ as a preparation for my test builds. For U-boot I will need to build a devicetree file from archarm/dts. I cannot rely just on the upstream fragments for u-boot. Imagine settings like initial fpga bitstream loading, handoff file setup for initialization, etc. In parts I may use .dtsi files from dts/upstream, though, but most of the u-boot particular devicetree setup will reside in arch/arm/dts, I guess (you may see later in the patches). I noticed when setting the option CONFIG_OF_UPSTREAM in `make menuconfig`, it prepends `dts/upstream/` to the included paths of the devicetree files. The resulting path for the .dts was then dts/upstream/arch/arm/dts/ and could not be found anymore. When I don't activate CONFIG_OF_UPSTREAM, dts/upstream is in the Makefile's include list anyway so that I easily can include from both locations. In conclusion, currently I'm calling a .dts for building the u-boot DT from arch/arm/dts. The file includes upstream stuff as .dtsi fragment from dts/upstream and handoff from local. CONFIG_OF_UPSTREAM does not seem to be necessary in this case. This approach currently works for me. If you strongly disagree, I may invest more time to find a way (or why there is currently no way) with CONFIG_OF_UPSTREAM. This was my question about. Anyway you may wait on v3 to understand better in source what I'm doing, or if I'm just messing around. > >>> 3.) What would be the best possibility to have a u-boot.dts with > >>> handoff setup in arch/arm/dts and append .dtsi files from the general > >>> dts/upstream - in case are there other boards are doing something > >>> similar? > >> > >> See above, maybe some of it helps. > > > > Yes. This helped. I can set base-board and boot mode now by Kconfig > > option with a generic .dts file. Note, it may still take some time, > > since I'd like to test the stuff still a bit on hardware before > > submitting something to the list. > > Sure I still found some bugs. When it's working (again), I'll let you guys know..
