VGA Problem about 440bx chipset

Richard Smith rsmith at
Tue Aug 31 10:17:00 CEST 2004

Chiu Gerald wrote:

> I found the work done about vga are:
> (1) allocate_vga_resource() in newpci.c
>   enbale io/mem of the vga adapter
>   then walk up the bridges setting the VGA enable

That should all be done already.

> (2) copy the vga bios to 0xc0000 using adlo,and run bochs bios.
>  I'm not sure if it had initilized the vga controller enough.  And I 

You will get a vga bios boot screen if it works.

> found there are some registers about AGP from 440bx northbridge 
> datasheet ( 82443bx hostbridge/controller),such as AGP capability 
> identifier register,AGP command register,AGP status register...
> But this work hadn't been done in linuxbios,maybe I need to set these 
> registers correctly according to the datasheet to enable AGP?

This is probally your problem.  None of the AGP stuff is setup in the
440bx code.  Only PCI cards have been used to date.  You will have to
write AGP init code.

Does V2 know anything about agp?  If so then its probally time to port
the 440bx stuff over to v2

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