Hi Masahiro, On 15 January 2015 at 12:10, Masahiro YAMADA <yamad...@jp.panasonic.com> wrote: > Hi > > 2015-01-15 23:46 GMT+09:00 Simon Glass <s...@chromium.org>: >> Hi, >> >> On 14 January 2015 at 01:18, Alexey Brodkin <alexey.brod...@synopsys.com> >> wrote: >>> Hi Simon, Masahiro-san, >>> >>> On Tue, 2015-01-13 at 20:18 -0800, Simon Glass wrote: >>>> > >>>> >> Probably I'm missing details of our Kconfig migration plan if one >>>> >> exists. Then I'd like to get a reference to the plan so I'm not >>>> >> attempting to do things that are already scheduled and could be even in >>>> >> a process of implementation. >>>> >> Otherwise if there's no current plan for Kconfig migration we may start >>>> >> discussion on how to deal with "commands" in particular. >>>> > >>>> > >>>> > I proposed the following way, but no big conversion movement has >>>> > happened yet. >>>> > http://thread.gmane.org/gmane.comp.boot-loaders.u-boot/199965/focus=200089 >>>> > >>>> > If you have an idea, please propose it. >>> >>> Unfortunately I cannot open this link - I see "Connection to 80.91.229.5 >>> failed". Do you mind to provide a link for the same message in >>> http://lists.denx.de ? >>> >>> >>>> > Kconfig conversion is a too big task to be done by a single indivisual. >>>> > Any suggestion, any form of contribution is very appreciated. >>> >>> Indeed and that stops me from starting this work as well. >>> So my point is: >>> 1) anybody may do updates to Kconfig like add more U-Boot commands, >>> some settings (CONFIG_SYS_xxx) >>> 2) board maintainers are responsible for updates in defconfigs and >>> corresponding headers in "include/configs/" >>> 3) that would be helpful if at (1) board maintainers are notified via >>> direct emails on the change that has been done >>> >>>> > I personally keep away from any global changes until >>>> > non-generic boards are dumped. >>>> > >>>> > As Tom said in the following mail, >>>> > http://lists.denx.de/pipermail/u-boot/2015-January/201032.html >>>> > we are going to remove lots of boards. >>>> > >>>> > I do not want to make extra efforts on non-generic boards. >>> >>> That makes sense but why don't we start implementation of changes in >>> good boards we know already converted to "generic"? There're even entire >>> arches that switched to "generic boards". >>> >>>> >> The point is commands are low-hanging fruits in terms of Kconfig >>>> >> migration - there're no extra options and tweaks, once all commands are >>>> >> added in Kconfig (essentially with dependencies etc) we may clean all >>>> >> board headers. The only real problem here is amount of work - lots of >>>> >> headers/defconfigs to patch. But still this is doable. >>>> > >>>> > >>>> > I realized one problem when I was doing this task >>>> > for my boards in commit 25e274e20208. >>>> > >>>> > The defconfigs of my boards are almost the same: >>>> > (configs/ph1_ld4_defconfig, configs/ph1_pro4_defconfig, >>>> > configs/ph1_sld8_defconfig) >>>> > >>>> > What is inconvenient as for defconfig is that >>>> > it does not support "include" directive like C headers. >>>> > >>>> > People generally like to add CONFIG_CMD_* to a common header file >>>> > such as include/configs/tegra-common.h >>>> > >>>> > On the other hand, on defconfig, we must touch each defconfig of the >>>> > board family. >>>> > >>>> > I have not been able to decide right direction to solve this issue. >>>> > >>>> > I think we need to discuss about how to live with lots of defconfigs. >>>> >>>> How about this: >>>> >>>> 1. Support an 'include' option in defconfig to include another file. >>>> This could take the form of CONFIG_DEFCONFIG_INCLUDES (comma-separated >>>> list of filenames). Don't allow nested includes - this CONFIG provides >>>> a complete list of includes. >>>> 2. When you use menuconfig to edit the config, it ignores the include >>>> and just writes out everything. Then it runs a simple script which >>>> parses the include files, and adjusts the file so that things in the >>>> includes are not repeated in the defconfig. >>>> >>>> I think this scheme would be good enough, but can probably be >>>> improved. At least it would be better than what we have. >>>> >>>> Or we could instead define particular includes for different purposes: >>>> >>>> - Arch >>>> - SOC >>>> - SOC Vendor >>>> - Board vendor >>>> - Board family >>>> >>>> We could then require that standard filenames are used, and search for >>>> the correct file based on the SOC/board/vendor setting, etc. >>>> >>>> As an example, for trimslice, we could search for arm.h, tegra.h, >>>> nvidia.h, compulab.h, some_family_name.h. >>>> >>>> This is less flexible though. >>> >>> Frankly I don't like this approach with post-processing steps. It will >>> inevitably end-up with messed up configs. >>> >>> Why don't we just use default values in Kconfig for ARCH/SOC/Board? >>> It's pretty obvious that 1 board may have N flavors but then have a >>> baseline options selected in "board/vendor/board_name/Kconfig" and only >>> put options that differ between boards in your defconfigs. >>> >>> This way "savedefconfig" will automatically strip down all extra lines >>> for a particular board. >>> >>> This is how things work in Linux kernel and Buildroot Kconfig-based >>> build systems. Probably I'm missing something here because U-Boot >>> differs from mentioned projects in some aspects - if so please correct >>> me. >> >> I started with this approach and Masahiro was not very keen on it. I'm >> OK with it, particularly as it is already supported, but I wonder >> whether we can do better. > > Honestly, I do not like baseline options in board-Kconfig very much. > The advantage is that it works without any change. > > > What I suggested before was to use scripts/kconfig/merge_config.sh. > > For example, put the SoC baseline options into tegra30_defconfig. > Put the difference from that into tegra30_(board).config > For example, > > make tegra30_defconfig tegra30_seaboard.config > make tegra30_defconfig tegra30_trimslice.config > > The disadvantage is that we would have to input more for the configuration > and has some impact on other projects such as BuildRoot...
Is there any way that tegra30_seaboard could include tegra30 automatically? > > > > Another option is "multi-image". > Actually barebox adopted this solution to solve the increasing > defconfig problem. > > In barebox, for example, all the Tegra boards share a single > defconfig, "tegra_v7_defconfig" > > tegra_v7_defconfig creates images for beaver, jetson, colibri, ac100, ... > > It takes advantage of Device Tree configuration and garbage collection. > So, it generates multipule images without increasing memory foot-print. > I've been keen on that approach and have taken some steps for Tegra and Exynos. Exynos is actually not to far away, but Tegra 124 pinmux approach makes this hard. Still I think this is the best solution - fewer boards to build also. > > > >> I notice that some kernel distributions have a script which pulls out >> common kernel configs in a separate file (e.g. for ARM, or for Tegra) >> for checking into source control, then combine them again for the >> kernel. This suggests that others have this problem too. It does seem >> like a convenient feature to be able to have some sort of hierarchy of >> config. >> >> Re messed-up configs, what will mess up? We can make it part of >> writing the config, perhaps. > > The hierarchical config strategy makes "savedefconfig" difficult , I think. > I never said it would be easy. Kconfig wasn't easy. > > >>> >>>> >> >>>> >> That's a separate topic. I do agree that CMD_FPGA makes not much sense >>>> >> for most of boards, as well as some others. >>>> >> >>>> >> And I think during migration process of commands to Kconfig it's a good >>>> >> time to reconsider default commands. >>>> > >>>> > Agree. >>>> > We should reconsider the default. >>>> > In my opition, most of the ones in config_cmd_default.h are not default >>>> > commands. >>> >>> Right but if we expect to switch to Kconfig solely for commands >>> selection we may not care much about contents of "config_cmd_default.h" >>> assuming it will go away sometime soon. >>> >>> Probably we may just focus on: >>> 1. Add all existing commands in Kconfig >>> 2. Select very few of them to be globally default >>> >>> (1) is pretty simple and anybody may do it if time permits >>> (2) requires wide discussion >>> >>> But what's really nice with Kconfig is its "savedefconfig". So we may >>> not set any commands as globally default and let every architecture, >>> board or defconfig to select really required options. >>> >>> Then once any option is marked as global (or even arch or board) default >>> in a matter of simple script that does "make XXX_defconfig && make >>> savedefconfig && mv defconfig configs/XXX_defconfig" all relevant >>> defconfigs will be correctly updated (default options will be stripped >>> out). >> >> Yes, it would be great to get all command configs into Kconfig. >> >> I wonder if we need a script which automates the conversion? The >> header file includes in the include/configs/... files makes this >> non-trivial. But if we had a script which could take a CONFIG as a >> parameter, remove it from all config headers, and add it to relevant >> defconfigs, it would be very useful. > > I have a Python script that moves each CONFIG from header files to > defconfig files. > > I wrote it for my local use, so it might not be very clean. > > > If necessary, I can share it on ML. Yes please! - Simon _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
