Open Stack

> FPGA configuration is a compiled binary blob written into
> non-volatile memory through a hardware interface. These similarities
> to firmware also result in many people actually calling it
> "firmware" even though, you're right, technically it's a mapping of
> gate interconnections and not really firmware in the conventional
> sense. In retrospect maybe I shouldn't have brought it up.

It's a super easy thing to conflate those two topics I think. Probably
calling one the "firmware" and the other the "bitstream" is the most
common distinction I've heard. The latter also potentially being the
"application" or "function."

> I wouldn't be surprised, though, if there *are* NFV-related cases
> where the users of the virtual machines into which some network
> hardware is mapped need access to alter parts of, say, an interface
> controller's firmware. The Linux kernel has for years incorporated
> features to write or rewrite firmware and other microcode for
> certain devices at boot time for similar reasons, after all.

Yeah, I'm not sure because I don't have a lot of experience with these
devices. I guess I kinda expected that they have effectively two devices
on each card: one being the FPGA itself and the other being just a
management device that lets you flash the FPGA. If the FPGA is connected
to the bus as well, I'd expect it to be able to define its own
interaction (i.e. be like a NIC or be like a compression accelerator),
and the actual "firmware" being purely a function of the management
device.

Either way, I think my point is that ironic's ability to manage the
firmware part regardless of how often you need it to change is limited
(currently, AFAIK) to the cleaning/prep phase of the lifecycle, and only
really applies anyway if a compute node when it is a workload on top of
the undercloud. For people that don't use ironic to provision their
compute nodes, ironic wouldn't even have the opportunity to manage the
firmware of those devices. I'm not saying Cyborg should fill the
firmware gap, just not saying we should expect that Ironic will.

--Dan