Hi Jagan, On Sun, Feb 24, 2013 at 10:58 AM, Jagan Teki <[email protected]> wrote: > Hi Simon, > > On Sun, Feb 24, 2013 at 11:55 PM, Jagan Teki <[email protected]> wrote: >> Hi Simon, >> >> On Sun, Feb 24, 2013 at 11:50 PM, Simon Glass <[email protected]> wrote: >>> Hi, >>> >>> On Sun, Feb 24, 2013 at 9:55 AM, Jagan Teki <[email protected]> >>> wrote: >>>> Hi Simon, >>>> >>>> On Sun, Feb 24, 2013 at 11:18 PM, Simon Glass <[email protected]> wrote: >>>>> Hi Jegan, >>>>> >>>>> On Sun, Feb 24, 2013 at 9:45 AM, Jagan Teki <[email protected]> >>>>> wrote: >>>>>> Hi Simon, >>>>>> >>>>>> On Sun, Feb 24, 2013 at 11:08 PM, Simon Glass <[email protected]> wrote: >>>>>>> Hi Jagan, >>>>>>> >>>>>>> On Sun, Feb 24, 2013 at 8:19 AM, Jagan Teki <[email protected]> >>>>>>> wrote: >>>>>>>> Hi Simon, >>>>>>>> >>>>>>>> Thanks for your response, please find my below comments. >>>>>>>> >>>>>>>> On Sun, Feb 24, 2013 at 9:24 PM, Simon Glass <[email protected]> wrote: >>>>>>>>> Hi Jagan, >>>>>>>>> >>>>>>>>> On Thu, Feb 21, 2013 at 9:03 AM, Jagan Teki >>>>>>>>> <[email protected]> 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
No - but you can just use 'mv' in a script external to the U-Boot build system. > > Some how I am able to create a fdt build on my target. > But what is this gpio mandatory, because currently my target currently > need a GPIO setup. > Add ing gpio.h/ with equivalent definitions is an extra overhead is > it? please explain. It is just a header file - unless you actually use the GPIO functions, you can compile with -ffunction-sections and you won't get the GPIO code included. Anyway, the overhead is small, if any. Regards, Simon > > Thanks, > Jagan. _______________________________________________ U-Boot mailing list [email protected] http://lists.denx.de/mailman/listinfo/u-boot
