[OpenBIOS] SOLVED: the mystery of Solaris on SPARC32 and the missing Forth arguments

[Blue Swirl]

On Fri, Oct 29, 2010 at 7:51 PM, Mark Cave-Ayland
<mark.cave-ayland at siriusit.co.uk> wrote:
> Blue Swirl wrote:
>
>>> 1) Are the memory properties physical or virtual? (totphys and totavail
>>> appear to be physical, where as totmap appears to be virtual?)
>>
>> I think that's right. We don't update totavail, which is a linked list
>> of all virtual memory zones available. So map_pages should add an
>> entry to the list.
>
> Yeah. The SPARC32 memory routines are quite simple in that they only have
> one item in each linked list; so while the memory regions represented in the
> device tree may not be exactly accurate, all memory within each region still
> meets the required criteria.
>
>>> 2) Should the relevant properties in the /memory and /virtual-memory
>>> nodes
>>> in the device tree be updated at the same time? (I think yes, as removing
>>> the properties causes boot to fail even on SPARC32).
>>
>> Probably and /virtual-memory nodes should have the same information as
>> totavail list.
>
> Yes, that sounds about right.
>
>> Great job, anyway!
>
> Thanks :)  Do you have access to any 32-bit Solaris images at the moment for
> testing purposes? Following up on the trap 0x29 error, it seems that Artyom
> sees this on the more modern versions of Solaris which suggests it may
> possibly be a qemu emulation bug (see the comments especially):
>
> http://tyom.blogspot.com/2009/12/solaris-under-qemu-how-to.html

There's a lot of comments. One of them says that the trap also happens
on real SS-5.

> So it would be useful to have someone who understands both SPARC32 and qemu
> to take a look (hint, hint!) ;)

Trap 0x29 is TT_DATA_ACCESS, invoked on access to unassigned memory by
QEMU. Perhaps enabling DEBUG_UNASSIGNED in target-sparc/op_helper.c
may reveal something.

It has been suspected that QEMU may be a bit too trigger happy with
unassigned memory accesses. There may also be an undocumented device,
or Solaris just tries to access a device which does not exist on SS-5.