[LinuxBIOS] ram_resource question

[joe at smittys.pointclark.net]

Quoting Corey Osgood <corey.osgood at gmail.com>:

> oops, meant to cc the list, apparently can't from my cell :(
>
> joe at smittys.pointclark.net wrote:
>> Quoting Corey Osgood <corey.osgood at gmail.com>:
>>
>>> It's board specific, if you saw that in i810, it's for onboard vga.
>>> -Corey
>>>
>>> On 10/12/07, joe at smittys.pointclark.net <joe at smittys.pointclark.net>
>>> wrote:
>>>> Hello,
>>>>
>>>> Can someone tell me what this memory region is reserved for?
>>>> It is 1MB to The Top Of Low Memory - 1MB right?
>>>> Is the last 1MB chipset specific or needed for the LinuxBIOS bounce
>>>> buffer?
>>>>
>>>> ram_resource(dev, idx++, 1024, tolmk - 1024;
>>>>
>>>> Oh, this is from northbridge.c if you were wondering. I need to know
>>>> this, because Intel IGD reserves memory from the The Top Of Physical
>>>> Memory down.
>>>> If this is the case should I subtract the IGD memory before or after
>>>> this function is called.
>>>>
>>>> Example 1:
>>>> tolmk -= IGD_MEMORYK
>>>> ram_resource(dev, idx++, 1024, tolmk - 1024;
>>>>
>>>> OR
>>>>
>>>> Example 2:
>>>> ram_resource(dev, idx++, 1024, (tolmk - IGD_MEMORYK) - 1024);
>>>> ram_resource(dev, idx++, (tolmk - IGD_MEMORYK) - 1024, tolmk -
>>>> IGD_MEMORYK);
>>>>
>>>>
>>>> Thanks - Joe
>>>>
>> Hmm, I saw where you set the
>>
>> /* Enable 1MB framebuffer. */
>> //pci_write_config8(ctrl->d0, SMRAM, 0xC0);
>>
>> In raminit.c but no mention of this in northbridge.c.
>
> I have no idea why I left the 1MB subtraction in there, probably because
> at the time I was planning on getting back to it and just haven't yet.
>
>> But if that is what that last 1MB is for I can just do a:
>>
>> ram_resource(dev, idx++, 1024, tolmk - IGD_MEMORYK;
>>
>> Right?? But, if I do this then is the IGD_MEMORYK going to be
>> initialized?
>
> Yes. But is there any way to use CONFIG_VIDEO_MB instead of a new config
> option? Perhaps have 0 or 2 = 512k?
>
>> From the datasheet:
>> The pre-allocated memory allows sizes of 512 KB, 1 MB, or 8 MB. The
>> system BIOS must properly initialize these regions.
>
> This is exactly what it's talking about ;)
>
> -Corey
>
Oh, thanks. Is CONFIG_VIDEO_MB a new option? I have not seen that one  
before. Can it only be used for MB? What about 512K? Do I just list it  
in Options.lb??


Thanks - Joe