On Wed, Sep 12, 2001 at 05:38:12PM +0300, Idan Lupinsky wrote:
> What I understand is that the EBSA285 has ISA memory space starting at
> 0x80000000 so the character memory is set to 0x800B8000. I've tried setting
> the charmem/scrmem variable to the PCI card (first RAM BAR base + 0xB8000)
That's not correct.
All PC video cards have "imaginary" IO and memory resources, which
correspond directly with the ISA mappings, ie, the following PCI bus
addresses:
0x3b0 - 0x3df (io, and 1K multiples there of)
0xa0000 - 0xbffff (memory)
These aren't specifically defined in the PCI standard (iirc), but are in
the PCI bridge standard (since bridges need to forward VGA accesses when
a control register bit is turned on).
The above resources are used irrespective of whether the BARs for the card
are setup to point elsewhere.
You need to arrange for the BIOS to have unconditional and uncontended
access to all the above regions, and some VGA BIOSes even require access
through the PCI BAR mappings.
Basically, you're finding out what a big mess PC hardware is, and all the
disgusting bachward hacks that need to be kept just to make new technologies
compatible with existing software. ;(
> 2. Should I see anything printed on the screen when the card initializes ?
Most VGA bioses display messages on initialisation.
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