[coreboot] Run PCI rom before PCI bus scan??

joe at smittys.pointclark.net joe at smittys.pointclark.net
Sun Feb 3 20:44:43 CET 2008

Quoting Stefan Reinauer <stepan at coresystems.de>:

> * joe at smittys.pointclark.net <joe at smittys.pointclark.net> [080203 02:34]:
>> Hello,
>> Is there a way to run a PCI rom before the PCI bus scan runs???
> Running a _PCI_ ROM without knowing where the PCI device lives (ie.
> before the _scan_) sounds impossible to me.
Shouldn't be impossible if you manually told coreboot where the PCI  
device lives.

> There might be something
> wrong with the approach. Why do you want/need to do this?
Again. coreboot is not able to find the 82562ET onboard nic. The  
lights on the nic are not coming on. And there is no eeprom,  
everything comes from the pci rom in the bios.

Here is what I think the PCI rom does with the original bios:

1. powers on and enables device
2. sets up PHY registers
3. sets up it PCI config registers
4. and requests use of the PCI bridge

If I could figure out how to do #1 the rest would be fairly simple to  
setup,although I am not exactly sure about PHY registers. Then I  
wouldn't need the pci rom at all.

> Joe, I think Carl-Daniel is asking: where is the image for the PCI ROM
> located? In BIOS flash, as it is on some systems? or on some PCI card?
> If on a PCI card, that makes running it before PCI is configured more
> "interesting". Not impossible, just harder.

Yes, the pci rom currently lives in the bios. It is a three part rom,  
Intel boot agent, Intel PXE, and the base code (I think the base code  
is the only real part I need??).

Thanks - Joe

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