Accessing PCI devices (low level programming)

Hello all,

I'm trying to figure out how OSes are working by making mine. For the
moment, I try to detect PCi devices in my computer.

So, I have took an Intel PCi bridge datasheet and I have read it. I have
tried to get device ID and vendor ID of device 0, function 0 on bus 0 with a
simple piece of code.

When I lauch it on my computer (there is not other OS in the computer, just
grub), it returns me vendor ID 0x8086 (Intel) and device Id..... I do not
remember the number, but it is good, it is my PCI bridge.

When I do the same under bochs, the IA-32 emulator, it returns me 0xFFFF for
both device ID and Vendor ID.

For sure, I have forgotten to initialize something, required for probing PCI
device, and my computer BIOS do this initialization for me and not bochs
BIOS.

So I would like to know if someone as already do such kind of low level
probing on PCI bus, or if he know where I could get some doc on this subject
(just on the initialization of PCI)

Thank very much
Sebastien

On Wed, 08 Oct 2003 21:43:03 +0200, Sebastien DI MERCURIO wrote:

Hello all,

I'm trying to figure out how OSes are working by making mine. For the
moment, I try to detect PCi devices in my computer.

[snip]

So I would like to know if someone as already do such kind of low level
probing on PCI bus, or if he know where I could get some doc on this
subject (just on the initialization of PCI)

Thank very much
Sebastien

You must make sure that your emulator is not hiding or vitualizing any
of your hardware devices.

You may find what you want by looking into the Linux kernel source.
There is an online cross-referenced source at http://lxr.linux.no.
Have a look in the "Documentation" directory first.
--
HTH
Murray

"Sebastien DI MERCURIO" wrote in
:

[cut]

So I would like to know if someone as already do such kind of low
level probing on PCI bus, or if he know where I could get some doc on
this subject (just on the initialization of PCI)

you can look at uniflash code, its pascal, but its better than nothing