Hi,
> To access Video-RAM there are two ways: One through the Bus and one
> through a memory-"window", which is stored in physical RAM.
Huh ? How does the card access that ? using Busmaster-DMA ?
In that case it gets very tricky, because, you will need kernel help
to get the physical address of the window and moreover on 64 bit
architectures, you need a way to allocate memory in the range that
is available for Busmaster-DMA.
> I wanna know, if there is a generic (= target-independet) way to get
> read/write access to that "window".
Are you absolutely sure that this is what "window" means ?
There is often talk about acess windows that work vice versa, i.e. by
mapping parts of the VRAM into the physical RAM adress space (the old
VGA 64k window at 0xa0000 is such a case), but I have rarely heard about
the other way round, except for unified memory architectures, where
System RAM == VRAM.
CU, Andy
--
Andreas Beck | Email : <[EMAIL PROTECTED]>
