[MPlayer-users] Re: Radeon frambuffer use if Radeon is not primary display?

[Arpi]

Hi,

> I mean, AGP-cards register themself as a PCI-Device on PCI-Bus 1 (on
> normal PC-Mainboards with only one two PCI-busses, namely PCI as bus:0
> and AGP as "bus":1) and are therefor accessable as PCI-Devices:
> 
> 00:08.1 Multimedia controller: Brooktree Corporation Bt878 (rev 11)
> 00:09.0 Ethernet controller: Accton Technology Corporation SMC2-1211TX (rev 10)
> 00:0d.0 SCSI storage controller: Advanced Micro Devices [AMD] 53c974 [PCscsi] (rev 10)
> 01:05.0 VGA compatible controller: Matrox Graphics, Inc. MGA G400 AGP (rev 82)
> 
> So there is (as far as I know) no limitation from the hardware point of
> view, but there may be software-specific problems.
Yes, _if_ the bridge to the card is initialized and working.
on-board agp bridge is usually initialized and working.
but the way for pci cards with agp chip:
1. initialize MB
2. initialize card -> enable pci-to-agp bridge on it
3. now you can access the device

it means your driver has to support the bridge chip on the card to
be able to access the vag chip.

> But: Every AGP-Card has to be VGA-compatible, or it is not allowd to be
> in the Display-Controller-Class and has to be put into the
> Multmedia-Controller-Class (that is where for example Voodoo2-Cards
> reside, since there are not VGA-compatible), so at least the vesafb
> should run.
vesa? it only works on the first card...
two card's vesa bios can't be mapped as they use the same address space
(c000:0000) and register space (3xx)

i don't know too much about the details (but it seems its' still much more
than you) but i believe what dri gurus said on dri-devel.
they actually wrote drivers for many cards and they know all teh details of
pci/agp stuff.


A'rpi / Astral & ESP-team

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