Hi Rasmus, On Wed, 26 Apr 2023 at 03:04, Rasmus Villemoes <rasmus.villem...@prevas.dk> wrote: > > On 25/04/2023 22.09, Tom Rini wrote: > > On Tue, Apr 25, 2023 at 10:02:01PM +0200, Rasmus Villemoes wrote: > >> On 25/04/2023 21.31, Tom Rini wrote: > >>> On Fri, Mar 17, 2023 at 11:26:39AM +0100, Rasmus Villemoes wrote: > >>> > >> > >>>> Now, the only way to be really sure is to build the world > >>>> with/without this patch and check if any .dtb file changes, but I > >>>> don't have the means to do that. > >>> > >>> So, yes, this causes a bunch of fail to builds, as you noted above. The > >>> easiest way I think to confirm things before / after would be to make a > >>> quick change to tools/buildman/builderthread.py and self.CopyFiles line > >>> for keep_outputs to also keep the dtb or some dts files so you can diff > >>> before / after to make sure the end result is the same. > >> > >> Do the builds outright fail, or do they fail in the sense that some > >> machinery detects a change in the binary artifacts? Can you point me at > >> one or two CI builds that show this? > > > > They outright fail to build, mt8516_pumpkin is the one I was testing > > with. > > Gah, of course. > > dtb-$(CONFIG_ARCH_MEDIATEK) += \ > mt7622-rfb.dtb \ > mt7623a-unielec-u7623-02-emmc.dtb \ > mt7622-bananapi-bpi-r64.dtb \ > mt7623n-bananapi-bpi-r2.dtb \ > mt7629-rfb.dtb \ > mt7981-rfb.dtb \ > mt7981-emmc-rfb.dtb \ > mt7981-sd-rfb.dtb \ > mt7986a-rfb.dtb \ > mt7986b-rfb.dtb \ > mt7986a-sd-rfb.dtb \ > mt7986b-sd-rfb.dtb \ > mt7986a-emmc-rfb.dtb \ > mt7986b-emmc-rfb.dtb \ > mt8183-pumpkin.dtb \ > mt8512-bm1-emmc.dtb \ > mt8516-pumpkin.dtb \ > mt8518-ap1-emmc.dtb > > means that we end up building a million .dtbs that are not actually > relevant to the board we're building for, and the value of > CONFIG_SYS_BOARD==mt8516 is of course completely inappropriate for > mt7622-rfb.dtb, and the nodes mentioned in mt8516-u-boot.dtsi don't > exist in mt7622... > > [To add insult to injury, it seems that currently mt8516-u-boot.dtsi is > not actually being included when building mt8516-pumpkin.dtb, but it > seems that the intention very much is that it should be - except that > mt8516-u-boot.dtsi has a typo (it refers to a label topckgen_ , but the > trailing underscore shouldn't be there) - confirming that it does in > fact not get used.] > > I wonder why this isn't already a problem, but I guess that in practice > we never hit the CONFIG_SYS_CPU or CONFIG_SYS_VENDOR cases. > > Not sure what to do. I think it's a little counterproductive to build > all these .dtbs when they are not needed, and silly to have to add one's > .dtb to some semi-random list - which is why I pushed for 3609e1dc5f4d > to get in. > > And since we very much allow the .dtbs to depend on various CONFIG_ > settings - both because different .configs can cause different > -u-boot-dtsi files to get included, and also because we allow direct use > of CONFIG_* values (or in #if, #ifdef), there's no guarantee that the > mt7629-rfb.dtb built with mt8516_pumpkin_defconfig is identical to the > one built with mt7629_rfb_defconfig. So what exactly is the point of > building all those irrelevant .dtbs?
Well we try to have one makefile rule for the SoC family, rather than one for each board, as it is a pain to deal with lots of rules. We sort-of follow what Linux does here. DT files are supposed to be stand-alone for the most part, although we do add binding includes. Since we include the autoconf you can use CONFIG options also, but using board-specific CONFIG options is not good practice, I think. After all, our goal is to upstream all these files, and CONFIG_SYS_BOARD won't be defined in Linux. > > So obviously my patch cannot go in as-is. But I do think there are some > things that need to be rethought in our build system. > > Now that all of CONFIG_OF_LIST gets built automatically, couldn't we > delete most if not all of the dtb-$(CONFIG_SOMETHING) += stanzas? > > Or to make the build of those extra dtbs a little more deterministic and > fix the issue with a random/wrong/inapplicable -u-boot.dtsi being picked > up, perhaps change the %.dtb rule so that the the magic *-u-boot.dtsi > file (whichever one applies) is only included when $@ is in > CONFIG_$(SPL_)OF_LIST? Eek... Regards, Simon
