Hi Simon, On Sun, Feb 24, 2013 at 11:50 PM, Simon Glass <s...@chromium.org> wrote: > Hi, > > On Sun, Feb 24, 2013 at 9:55 AM, Jagan Teki <jagannadh.t...@gmail.com> wrote: >> Hi Simon, >> >> On Sun, Feb 24, 2013 at 11:18 PM, Simon Glass <s...@chromium.org> wrote: >>> Hi Jegan, >>> >>> On Sun, Feb 24, 2013 at 9:45 AM, Jagan Teki <jagannadh.t...@gmail.com> >>> wrote: >>>> Hi Simon, >>>> >>>> On Sun, Feb 24, 2013 at 11:08 PM, Simon Glass <s...@chromium.org> wrote: >>>>> Hi Jagan, >>>>> >>>>> On Sun, Feb 24, 2013 at 8:19 AM, Jagan Teki <jagannadh.t...@gmail.com> >>>>> wrote: >>>>>> Hi Simon, >>>>>> >>>>>> Thanks for your response, please find my below comments. >>>>>> >>>>>> On Sun, Feb 24, 2013 at 9:24 PM, Simon Glass <s...@chromium.org> wrote: >>>>>>> Hi Jagan, >>>>>>> >>>>>>> On Thu, Feb 21, 2013 at 9:03 AM, Jagan Teki <jagannadh.t...@gmail.com> >>>>>>> wrote: >>>>>>>> Hi All, >>>>>>>> >>>>>>>> I am planning to use devicetree on u-boot. >>>>>>>> I have an experience to work with devicetree on Linux. >>>>>>>> >>>>>>>> For u-boot, I have read doc from doc/README.fdt-control. >>>>>>>> I see some dts usages on tegra boards. >>>>>>>> >>>>>>>> I have lot of confusions with the concept itself. >>>>>>>> >>>>>>>> Is Linux and u-boot devicetree concept and build system are same? >>>>>>> >>>>>>> I don't really understand this question sorry. U-Boot and Linux use >>>>>>> the device tree mainly for run-time configuration of drivers, so that >>>>>>> the same driver code can operate on different boards. >>>>>> >>>>>> I am some how confusing the fdt usage in u-boot. >>>>>> Because when compared to Linux, u-boot fdt setup mandatory to require >>>>>> the CONFIG_DEFAULT_DEVICE_TREE >>>>>> on the config file [from your previous comments]. >>>>>> >>>>>> is this the only difference when compared to Linux i guess..is it? >>>>>> Linux defconfig file does need to hot-code >>>>>> the dts. >>>>> >>>>> Yes - that is a difference. Linux provides a way to build .dts files >>>>> but it is not mandatory. At present it is mandatory with U-Boot, and >>>>> only one file is built. It can easily be ignored though. >>>> >>>> Ok. >>>> >>>>> >>>>>> >>>>>>> >>>>>>>> >>>>>>>> Suppose I have 4 boards J1, J2, J3 & J4 on my soc "emb".of vendor >>>>>>>> "vast" >>>>>>>> For this requirement I have >>>>>>>> board/vast/dts/J1.dts >>>>>>>> board/vast/dts/J2.dts >>>>>>>> board/vast/dts/J3.dts >>>>>>>> board/vast/dts/J4.dts >>>>>>>> >>>>>>>> include/configs/emb_common.h ==> single configuration of all SOC >>>>>>>> needed definitions >>>>>>>> like defconfig in Linux. >>>>>>>> >>>>>>>> do I need any more files? >>>>>>> >>>>>>> That's enough for the basics I think. >>>>>> >>>>>> Is dtsi file require to add it on arch folder along with above. >>>>> >>>>> If your architecture is not one of those already supported (like arm >>>>> tegra/exynos and x86) then yes you need to add this file in >>>>> arch/<arch>/dts. What architecture are you using? >>>> >>>> My architecture is armv7, may be for me dtsi not required as arm is >>>> existing architecture >>>> to support fdt on u-boot.. is it? >>> >>> Which sub-arch? If it is tegra/exynos5250 then you might be OK. For >>> something else, you should get the kernel's .dtsi file for that chip. >> >> I am having armv7, xilinx zynq soc..but i coun't get any .dtsi on kernel >> source. >> may be I will create new one. > > OK, well if the kernel doesn't have FDT support yet then yes you will > need to create a new one. > >> >>> >>>> >>>>> >>>>>> >>>>>>> >>>>>>>> >>>>>>>> In emb_common.h i am defining >>>>>>>> CONFIG_OF_SEPARATE is it sufficient? >>>>>>> >>>>>>> And CONFIG_OF_CONTROL >>>>>>> >>>>>>>> >>>>>>>> My plan is to build u-boot and then build the dtb with specific >>>>>>>> board and then combine. >>>>>>> >>>>>>> That's fine, and is how we do things on Chromium also. U-Boot tries to >>>>>>> build an FDT even with CONFIG_OF_SEPARATE, so you need to put a >>>>>>> default device tree file in your emb_common.h file that it can find. >>>>>>> But you can ignore it, and for flashing your boards just use >>>>>>> u-boot.bin plus whatever .dtb you want to select. >>>>>> >>>>>> So I will add the fdt support and then build the u-boot. >>>>>> Is there any separate u-boot build command to build dts file. >>>>>> My plan is to combine both u-boot and dtb. >>>>> >>>>> You can run dtc yourself if you like - see Makefile/dts for how it is >>>>> done there. Once you have the .dtb binary, the easiest thing is to add >>>>> it to the end of u-boot.bin, as described in README.fdt-control. >>>> >>>> Thanks, I tried with above setup for adding dts. >>>> I have added simple dts file on my board. >>>> >>>> I got the below build error >>>> /proj/mypc/u-boot/include/asm/gpio.h:1:27: fatal error: >>>> asm/arch/gpio.h: No such file or directory >>>> compilation terminated. >>>> make[1]: *** No rule to make target `.depend.fdtdec', needed by >>>> `.depend'. Stop. >>>> >>>> is gpio.h is mandatory for fdt build? >>> >>> Yes because basic GPIO support is included. You can create one for >>> your sub-arch and make it #include <asm-generic/gpio.h> as a starting >>> point. >>> >> >> Should I create an empty gpio.h file..it still asking some gpio >> definitions right.. > > It might be OK if you just have "#include <asm-generic/gpio.h>" in that file.
Thanks. Finally I have created u-boot-dtb.bin. for building dtb separately I have used $ make DEVICE_TREE=zynq .. it creates a u-boot.dtb is there any option for building separate name, for example I need to create zynq.dtb Thanks, Jagan. _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
