Re: [Qemu-devel] Re: [PATCH] register a single area for vga bios and option roms

[Carl-Daniel Hailfinger <c-d.hailfinger.devel.2006@gmx.net>]

On 09.04.2009 19:48, Anthony Liguori wrote:
> Glauber Costa wrote:
>> Those guys are not different in nature. They're all roms,
>> not blessed with the graces of being written to. So there's
>> not need to issue multiple requests to memory registration areas:
>> just treat them as brothers, and put them all in the same
>> region.
>>
>> It also has the nice side effect of improving the loading code
>> a little bit.
>>
>> Signed-off-by: Glauber Costa <glommer@redhat.com>
>>   
>
> The vga bios is just an option rom, right?  So why can't we treat the
> vga bios as an option rom and eliminate the specific code for dealing
> with VGA bios.
>
> The real problem here is that we should be registering the option rom
> space once and doing that in page boundaries.

AFAIK shadowed option ROMs can be aligned at 1 kB boundaries and may
modify themselves. Quite a few VGA BIOSes do that to reduce their memory
footprint after hardware initialization is complete.


Regards,
Carl-Daniel

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