On 15.04.19 17:56, Sasha Levin wrote: Hi, > +The driver acts as a thin layer that passes commands to and from a TPM> +implemented in firmware. The driver itself doesn't contain much logic and is> +used more like a dumb pipe between firmware and kernel/userspace. Is that TPM already used in production or yet an PoC ? IOW: can the protocol be changed ? If so, I'd prefer using 9P for that. This already proven well, not just for grid computing (where it originally came from), but also in things like virtio, etc. In general, many of the hardware/chip interfaces out there basically deal with either either passing around some data packets or streams, or reading/setting some attributes. But everybody seems to do that part in his own special way - that takes up a big share of the driver development resources and final code - and that needs to be repeated for each OS. In many, many cases a standard protocol like 9P could already provide this - if folks would just use it :p Therefore, I'm really a strong supporter of the idea of using 9P for this. In your case, you could design the highlevel TPM interface like with a tcp stream / socket or a synthetic filesystem, and for the lowlevel part just like kvm does w/ virtio. In case you have no experience w/ 9P+friends, feel free to ask, I'll to my best to explain it :) --mtx -- Enrico Weigelt, metux IT consult Free software and Linux embedded engineering info@xxxxxxxxx -- +49-151-27565287
