[U-Boot] u-boot.dtb vs. dts/dt.dtb output filename, also O= vs BUILD_DIR=

[Masahiro Yamada]

Hello Stephen,



> Prior the to kbuild conversion, U-Boot used to produce file u-boot.dtb
> in the root of the object tree. Now it doesn't, but I think puts the
> same file in dts/dt.dtb instead. Was this a deliberate change?

The patch is already on Patchwork and I think it should be applied soon.
Sorry for the inconvenience.

> We have some flashing utilities that build U-Boot, then copy this result
> file. This utility no longer works because the file it's looking for no
> longer exists. I'd rather fix the U-Boot build process so its output
> filenames don't change, than fix the utility to look for a variety of
> different output filenames. Are you OK with a patch reverting the output
> filename change?
> 
> Related, I also found that pre-Kbuild, I could "make BUILD_DIR=...", but
> now I have to "make O=...". That's also an external change in behaviour.
> Was that intentional?


"make O=..." are always supported before and after Kbuild.
(I guess many peaple use it for less typing.)

And yes, "BUILD_DIR" was replaced with "KBUILD_OUTPUT"
when I impored many build scripts from Linux Kernel.

All overridable variables  in Kbuild are prefixed with "KBUILD_",
so I am following this rule.
I hesitate to rename only KBUILD_OUTPUT  inconsistently.

Best Regards
Masahiro Yamada