re-scanning the PCI bus after boot for configurable device...

re-scanning the PCI bus after boot for configurable device...

[Dave Airlie]

hi,
	I've got a PCI card that has an FPGA on it which I want to program
at run time, and then load a device driver for depending on what I've
loaded in to the FPGA,

The FPGA is downloaded via JTAG so that is all fine, but if I boot Linux,
download over the JTAG, how can I get Linux to see the device? can I use
the hotplugging support or do I still need to do more work? I know the
hotplug allows for PCMCIA and CompactPCI to add devices after boot, but
this is plain PCI but the device won't be there until the system is
running,

I know I can in theory put an image in the FPGA from an EEPROM which
enough to get by, but I'd rather not put an EEPROM anywhere near the board
if possible,

Thanks,
Dave.

-- 
David Airlie, Software Engineer
http://www.skynet.ie/~airlied / airlied@skynet.ie
pam_smb / Linux DecStation / Linux VAX / ILUG person

Re: re-scanning the PCI bus after boot for configurable device...

[Greg KH]

On Tue, May 13, 2003 at 02:29:33AM +0100, Dave Airlie wrote:
> 
> hi,
> 	I've got a PCI card that has an FPGA on it which I want to program
> at run time, and then load a device driver for depending on what I've
> loaded in to the FPGA,
> 
> The FPGA is downloaded via JTAG so that is all fine, but if I boot Linux,
> download over the JTAG, how can I get Linux to see the device? can I use
> the hotplugging support or do I still need to do more work? I know the
> hotplug allows for PCMCIA and CompactPCI to add devices after boot, but
> this is plain PCI but the device won't be there until the system is
> running,

I've posted a driver to the linux-hotplug-devel mailing list a year or
so ago that might help you out with this.  On module load it rescans the
PCI address space, adding or removind devices that are new or now gone.
This will probably do what you want.

I didn't write the driver, and it's probably very out of date by now,
but it's something for you to start with if you are interested.

Good luck,

greg k-h

Re: re-scanning the PCI bus after boot for configurable device...

[Dave Airlie]

>
> I've posted a driver to the linux-hotplug-devel mailing list a year or
> so ago that might help you out with this.  On module load it rescans the
> PCI address space, adding or removind devices that are new or now gone.
> This will probably do what you want.

I persume it's this one
http://marc.theaimsgroup.com/?l=linux-hotplug-devel&m=101312609603679

and it looks the business, I don't have my hardware yet but I this answers
the is it possible question enough :-)

Thanks Greg,
Dave.

-- 
David Airlie, Software Engineer
http://www.skynet.ie/~airlied / airlied@skynet.ie
pam_smb / Linux DecStation / Linux VAX / ILUG person

Re: re-scanning the PCI bus after boot for configurable device...

[Greg KH]

On Tue, May 13, 2003 at 05:08:49AM +0100, Dave Airlie wrote:
> >
> > I've posted a driver to the linux-hotplug-devel mailing list a year or
> > so ago that might help you out with this.  On module load it rescans the
> > PCI address space, adding or removind devices that are new or now gone.
> > This will probably do what you want.
> 
> I persume it's this one
> http://marc.theaimsgroup.com/?l=linux-hotplug-devel&m=101312609603679

That's the one.

If you get it working on 2.5, I'd be interested in adding it to the main
kernel tree, as people ask for this kind of stuff every once in a while.

Good luck,

greg k-h