Add the possibility to use another DTC

[manu]

Summary

Add the possibility to use another DTC

Add a make.conf DTC variable that control which DTC (Device Tree Compiler) to use.

Test Plan

Compile kernel for ARM which uses DTC.

[imp]

sys/conf/kmod.mk

67 ↗

(On Diff #25115)

Don't we need a .export here to pass the value to the subshell that does the compile?

[bdrewery]

sys/conf/kmod.mk

67 ↗

(On Diff #25115)

Yup, and please use "dtc" as the script had, not "/usr/bin/dtc". Otherwise we won't be calling one in the build tools directory, if we built one. Even if we don't do that now, it's better practice to support build tools directories being set via PATH.

sys/tools/fdt/make_dtb.sh

9 ↗

(On Diff #25115)

I recommend adding a default DTC variable here in case none is sent from environment. This is done for MACHINE on line 15 as well but is simpler:

: ${DTC:=dtc}

This will set DTC to dtc if no value is set yet.

[bdrewery]

sys/conf/kmod.mk

67 ↗

(On Diff #25115)

I hadn't checked yet, but we do build dtc as a build tool in bootstrap-tools. So we definitely don't want "/usr/bin/" here. That would make the manpage inaccurate too.

[manu]

Yeah I definitely doesn't work for me as is (also I'm sure it did when I created this review but I must have had some local mods).
I can't seems to be able to use .export, are .export variabled really exported for subshell ? Where is this documented ?

[manu]

Export the DTC variable in bsd.dtb.mk and correct man page.

[wblock]

share/man/man5/make.conf.5

27 ↗

(On Diff #25210)

Please remember to bump .Dd.

[bdrewery]

sys/tools/fdt/make_dtb.sh

19–21 ↗

(On Diff #25210)

This is redundant, you don't need the if and fi lines, just the middle ':' line is enough here, or make the middle line DTC=dtc.

[manu]

Update based on comment from from bdrewery@ and wblock@

[manu]

Update to latest HEAD

[imp]

Looks like all of Bryan's feedback has been answered, and that answers the questions I had.

[wblock]

head/share/man/man5/make.conf.5

27

Please bump this date.

183

This should be

is initially set to the value of
.Dq Li dtc .