There were two main problems here:
1.) sys/dts/Makefile.inc is not included from various */overlays directories
by default, only ../Makefile.inc
2.) When shelling out for DTS/DTSO, cwd != .CURDIR, so enumeration always
failed
These changes allow make test-dts and make test-dtso to function in their
respective directories.
Reviewed by: manu
MFC after: 3 days
Differential Revision: https://reviews.freebsd.org/D17961
DTB Overlays are useful to change/add nodes to a dtb without the need to
modify it.
Add support for building dtbo during buildkernel.
The goal of DTBO present in the FreeBSD source tree is to fill a gap in
time when we submit changes upstream (Linux). Instead of waiting 2 to 4 months
we can add a DTBO in tree in the meantime.
This is not for adding DTBO for capes/hat/addon boards, those will be
better to put in a ports.
This is also not for enabling a i2c/spi/pwm controller on certain pins,
each user have a different use case for those (which pins to use etc ...)
and we cannot have all possible configuration.
Add a dtbo for sun8i-h3-sid which add the SID node missing in upstream dts.
Reviewed by: kevans
Differential Revision: https://reviews.freebsd.org/D14782
