Re: [Qemu-devel] [PATCH v12 4/4] arm: SoC model for Calxeda Highbank

[Peter Maydell]

On 19 January 2012 23:17, Rob Herring <address@hidden> wrote:
> On 01/19/2012 03:44 PM, Peter Maydell wrote:
>> On 19 January 2012 21:31, Mark Langsdorf <address@hidden> wrote:
>>> +    highbank_binfo.board_id = 0xEC10100f; /* provided by deviceTree */
>>
>> Where does this number come from? It's not in
>> http://www.arm.linux.org.uk/developer/machines/
>>
>> Is 3027 (==0xbd3) you?
>> http://www.arm.linux.org.uk/developer/machines/list.php?id=3027
>>
>
> Much of the data there is wrong as none of it is used. 0 or -1 is the
> right value as those are obviously meaningless. A highbank kernel will
> never be booted without devicetree and in that case this number is
> irrelevant. This is the legacy boot interface and qemu really needs to
> learn to boot with a separate dtb.

Yeah, but the documentation even for DTB boot says we should pass
in a machine number. If 0 or -1 are right then there should be
some documentation that says so. I'll accept "mailing list post
from some authoritative person [eg Grant Likely]" if necessary.
But this is an ABI between boot loaders and the kernel so I don't
want to just have something random that happens to work. (And in
particular if -1 is the officially sanctioned number then we need
to fix arm_boot to be able to pass values >16 bits wide.)

-- PMM