Re: [Qemu-devel] [PATCH v2 30/30] target-sparc: fix up niagara machine

[Artyom Tarasenko]

On Fri, Jan 27, 2017 at 3:27 PM, Paolo Bonzini <address@hidden> wrote:
>
>
> On 27/01/2017 15:06, Markus Armbruster wrote:
>>> Is rom_add_file_fixed supposed to mark the memory region read-only? Or
>>> should it be created read-only before calling rom_add_file_fixed?
>> I'm not familiar with the memory API, but the fact that you're getting
>> RW suggests that you need to mark read-only yourself.  Suggest to
>> examine similar code elsewhere for additional clues.
>>
>>>> The monkey-patching of dinfo->is_default is to silence the "Orphaned
>>>> drive without device" warning.  Naughty.
>>>>
>>>> This use of -drive if=pflash is highly unorthodox.  To suggest better
>>>> ways, we need to understand the role of "the virtual ramdisk".  Can you
>>>> explain?  How does it work on a physical system?
>>> AFAIK except for simulators it's only used on FPGA boards. It's what
>>> the comment says: a kind of initrd, but it resides outside of the
>>> partition RAM. So, it is a RAM region pre-filled with data in the way
>>> not visible to the guest.
>>>
>>> I would have used an -initrd option instead of -pflash, but it
>>> required a -kernel option, and there is no sensible way to use the
>>> -kernel with Solaris.
>>> If QEMU had something like a nvram-disk - it would have worked here the 
>>> best.
>>
>> Have you considered pressing -bios into service?  -option-rom?  -object
>> memory-backend-file?  Paolo, any recommendations?
>
> Yeah, I think -bios is closest.

I think it may sound misleading to a user: it's an optional
(NV)RAM-disk, not a part of a firmware.
Maybe -object memory-backend-file would do it, but it clears the file
on reset, doesn't it?

> By the way, where do I get all the .rom
> files for the Niagara board?  "make check" complains about them.

The machine uses the firmware supplied with the OpenSPARC T1 project,
http://download.oracle.com/technetwork/systems/opensparc/OpenSPARCT1_Arch.1.5.tar.bz2
in the directory S10image/

Also I posted a patch to silence "make check" a couple of days ago.

-- 
Regards,
Artyom Tarasenko

SPARC and PPC PReP under qemu blog: http://tyom.blogspot.com/search/label/qemu