[LinuxBIOS] Dummy pci dev for image on a usb flash drive

joe at smittys.pointclark.net joe at smittys.pointclark.net
Fri Sep 28 07:02:16 CEST 2007

Quoting Baski <kbaski at yahoo.com>:

>> On Wed, Sep 26, 2007 at 10:19:08PM -0700, Baski wrote:
>>> I want to place an option ROM image on a raw USB flash drive.
>> Please explain why, otherwise we can't help you much.
>>> It will be an option ROM image of a proper controller with correct
>>> option ROM and PNP headers. How can we make linuxBios to look for
>>> this drive and allocate dummy pci resources like bus 0 dev-xx, fun
>>> yy and irqs?
>> First, LB has no USB drivers. You could move what is in FILO over
>> though.
>> More relevant is the fact that LB can't allocate resources to
>> hardware that does not exist. Unless you have the controller itself
>> it's not possible to set any resources. They are set in registers
>> (RAM) that is mandatory for PCI cards to have (the so called PCI
>> config space) and no card means nowhere to set things.
>> Furthermore, option ROMs are not really "compatible" with LB, the
>> idea is to try to use existing open source drivers with LB instead of
>> binary blobs with broken interfaces.
>> So - what do you want to accomplish with your idea? There may be a
>> better way to do it, or it may be best to forget the whole thing.
>> We can't say without more info.
>> //Peter
>> This is for my MS project. We want to simulate a PCI card and use
>> one of the CPU cores to do our processing. We would also want to
>> reserve that core.
>> We want to create the dummy pci device so that OS driver can
>> communicate with the emulated card. What methods would you suggest?
>> Thanks.
> I don't get it. Why do you need to simulate a pci card?? Why not just
> use a real one??
> Thanks - Joe
>   Hi Joe,
>   That's the whole aim.  We want to emulate a pci card and test it   
> with a real driver before an actual card is built.
>   Can someone throw me some pointers?
>   Thx

Hmm, I don't know if this is even phisicaly possible. In the real  
world venders create proto types of the hardware first and then the  

You would have to somehow trick the PCI Bridge into thinking there was  
a PCI Device in a slot. Good Luck!

Thanks - Joe

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