Hi Felix,

On a custom MPC8536 board running linux-2.6.31,
I'd like to load FPGA code from linux and then rescan
PCI-E bus to discover FPGA device. Is that possible ?
When linux boots FPGA is not loaded, so initial PCI
scan does not detect it.

I've tried playing with /sys/bus/pci/rescan and /sys/bus/pci/devices/.../rescan
but didn't have much success.

This can be made to work using the kernel hot-swap
interface. PCI devices have an ENUM# interrupt that
they assert when inserted or extracted, and the host
hot-swap driver can be hooked up to it. PCI-E may
have a similar mechanism, if it does, then when your
FPGA configures as a PCI-E device, it can assert that
interrupt line (or send the appropriate PCI-E
message to simulate that interrupt).

However, even if PCI-E does not have the concept of
an ENUM# interrupt there is a way to generate a fake
hot-swap event and generate a re-scan of the PCI bus.

I haven't tested the kernel hot-swap interface, but I
know that Ira did, so I'll cc him on this mail, and he
can let you know what he tested.

Cheers,
Dave

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