Stand-alone DTB build fails

[Warner Losh]

On Apr 25, 2014, at 8:56 AM, Ron Brown <ron.brown at arcserv.com> wrote:

> The FreeBSD Wiki at https://wiki.freebsd.org/FlattenedDeviceTree refers to
> building a dtb in the following manner:
> 
> --
>  On platforms capable of running loader(8) the default scenario is to use
>  a stand-alone DTB file, which is handled by the loader and handed over to
>  kernel at boot time. In this approach, a DTB should be created at kernel
>  build time:
> 
>  If FDT_DTS_FILE is specified in the kernel config file, the DTB is
>  compiled automatically as part of the buildkernel stage. The user does
>  not have to perform any explicit steps.
> 
>  If the default DTS file is not specified in the kernel config file, the
>  DTB needs to be created separately by the user with the builddtb target:
> 
>    $ make builddtb FDT_DTS_FILE=mpc8572ds.dts
> --
> 
> However, this fails with:
>    ERROR: Specified DTS File (zedboard.dts) does not exist!
> 
> This is because /usr/src/Makefile.inc1 uses the MACHINE environment
> variable to find FDT_DTS_FILE:
> 
> Starting at line 1836:
>    if [ ! -f ${.CURDIR}/sys/boot/fdt/dts/${MACHINE}/${FDT_DTS_FILE} ]; ...
>    echo "ERROR: Specified DTS file (${FDT_DTS_FILE}) does not \
>    exist!"; \
> 
> MACHINE refers to the currently running system, however most of the ARM
> development is cross-compiled and the zedboard .dts resides in the dts/arm
> directory while MACHINE points if to the dts/amd64 directory.
> Should Makefile.inc1 instead refer to TARGET or something similar?
> 
>    if [ ! -f ${.CURDIR}/sys/boot/fdt/dts/${TARGET}/${FDT_DTS_FILE} ]; ...

I think this is a mistake, but the make_dtb script also makes a similar
mistake (because it expects to be called from a different context). I’ll
sort this out and post a patch.

Warner