Calling Bios 32 service

[Slasher]

Hi guys,
I was wondering if anyone has been able to call Bios32 service 0 from a paged protected mode os?
I seached bios from 0x0e0000 to 0x0fffff as specified in the PCI BIOS spec.
I found Bios 32 with entry point 0x00F9550. I tried calling it with
mov eax,0x49435024 ;($PCI)
mov ebx,0 ;(find this service)
call 0x00f9550
but the system either gives a page fault or general protection fault.
The entry point is covered by my 1:1 linear mapping and I'm at CPL 0 with access to IO space.
Can you guys help?
Thanks

[Slasher]

Okay, I've solved it.
I should have pushed cs before making the call.
it is a far call
I'll get back to you guys if I fail in calling the PCI Bios that is returned by this Bios 32 call.
Thanks

[Perica]

..

[Slasher]

Using Bios 32 directory you can find out where the PCI Bios is. Using this information you can make far calls to the PCI BIOS directly.
Some uses could be
1. Use the PCI bios to find out the type of configuration and special cycle mechanism which the system supports. And then select the right pci driver to handle it. i.e Mechanism 1 or mechanism 2

2.Use it to collect info on all the pci devices installed before using your own pci driver. It's a kind of fail safe thing because at least you are sure that you got the right info for each device. You can use this as a means of testing your own PCI device search code by comparing results.

3. Use it to configure the devices.
etc
you just have to twist it to your needs.
Corrections and more suggestions are very welcomed.

[barrios]

I am interested in "Calling Bios 32 Service". but I have no related documents and knowledge. I hope that You recommed related documents for me.

Thank you.

[Slasher]

So far I've only used it to find the PCI bios
check this link

you could also use "calling Bios 32" in search engines

[Perica]

..

[Slasher]

Yeah, But I don't know how efficient calling the Bios all the time from your Pmode Os will be. I'm just using it to get necessary info so that i can use the appropriate direct access method(s) to communicate with PCI devices. i.e finding out if its a mechanism 2 or 1 PCI system, attached devices, and that kind of stuff. Only used so far at setup time.

[Moose~]

Hi all,
being the owner of the site listed, im getting lots of referals from mega-tokyo forums from the previous post.

This post is to inform that the above link is incorrect and old.

The correct link to that doc should be this

Moose

[Pype.Clicker]

fixed link. thanks.