Re: [Qemu-devel] [PATCH] [RFC] Variable video ram size option

[Trolle Selander <trolle.selander@eu.citrix.com>]

Paul Brook wrote:
> On Friday 09 January 2009 12:45:47 Trolle Selander wrote:
>   
>> +#ifdef TARGET_SPARC
>> +    vga_ram_size += (1024 * 1024);
>> +#endif
>>     
>
> This looks pretty bogus.
>
>   
Possibly. The previous static definition added one meg to the default
VGA_RAM_SIZE if TARGET_SPARC was set, and I merely wanted to retain that
behavior. If someone who is familiar with the SPARC target and knows the
reason for the added meg of ram in the previous code can assure that
this won't be needed with the configurabe ram patch, I'll be happy to
drop that bit.

>> +    if ( vga_ram_size > 16*1024*1024 )
>> +    {
>> +        fprintf(stderr,"The stdvga/VBE device model currently has no use
>> for more than 16 Megs of vram. Video ram reduced to 16M. \n"); +       
>> vga_ram_size = 16*1024*1024;
>>     
>
> I'm pretty sure this is wrong. VBE alows arbritary sized virtual framebuffers.
>
> Paul
VBE does, but the stdvga/VBE device model currently cannot _make use_ of 
more, since there highest resolution provided is 2560x1600x32 = 16Megs. 
The features required to make use of VRAM that is not used for the 
framebuffer itself are not there, either, and hence any additional 
memory would just be wasted. Anyone who would want to add features to 
the stdvga device or to the VBE bios can easily remove or change this check.

-- Trolle