[LinuxBIOS] Problems with Filo booting - HELP

Corey Osgood corey.osgood at gmail.com
Thu Oct 4 08:13:28 CEST 2007

joe at smittys.pointclark.net wrote:
> Here is my ram_check from 1-128MB. It appears to fill the ram ok. But
> only returns a value of 0xffffffff. Does this mean the ram is WO
> (write only) for some reason? Thanks again for your help.

Okay, this is mostly a shot in the dark, but it's the only thing I can
find that might cause something like this. I'm looking at the AGP size
register (APSIZE, 0xb4) in the datasheet, and the default value is 0x00,
which is 256MB (!!). I also don't see anywhere that AGP has to be
explicitly enabled, it looks like it's enabled by default (yes, I see
AGPCMD, but it says cycles will be ignored, not that the device is
actually disabled and freeing the aperture memory).

Long story short, try setting the AGP aperture to 32MB and moving the
aperture base (APBASE, 0x10-13) to somewhere else, preferably wherever
the stock bios moves it to. Even if it's not the root cause, it'll get
it out of the way for later.


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