[SLOF] [PATCH slof v3 5/5] fdt: Pass the resulting device tree to QEMU

Segher Boessenkool segher at kernel.crashing.org
Thu Oct 5 01:36:07 AEDT 2017


On Tue, Oct 03, 2017 at 05:28:43PM +1100, David Gibson wrote:
> On Tue, Oct 03, 2017 at 04:15:23PM +1100, Alexey Kardashevskiy wrote:
> > I tested the blob by storing it from QEMU to a file and decompiling it;
> > this produces error which I do not really
> > understand as the name of the root is an empty string (literaly:
> > 00 00 00 01  00 00 00 00) and yet this error:
> > 
> > aik at fstn1-p1:~$ dtc -f -I dtb -O dts -o dbg.dts dbg.dtb
> > ERROR (name_properties): "name" property in / is incorrect ("/" instead of base node name)
> > Warning: Input tree has errors, output forced
> 
> The reason for this error is it's not to do with the "node name" as
> given after the FDT_BEGIN_TAG, but with the "name" property.  That's
> not required in FDT, but if supplied should match that node name
> exactly.  IIRC, however, for human readability runtime OF treats
> 'name' of the root node as being '/'.

SLOF usually sets the "name" property in the root node to "/".  The
standard actually requires "Name of system’s manufacturer and model
number, e.g., “ABC,mat750”", which is also not an empty string (nor
an absent property).

> Arguably that is a bug in dtc - '/' as the name property in the root
> is probably acceptable.  On the other hand, you should probably just
> omit the 'name' properties when you flatten the tree.

Yup, it is one of the differences between FDT and OF device trees.


Segher


More information about the SLOF mailing list