Re: [RFC PATCH 17/22] thunderbolt: Add initial support for USB4

From: Mika Westerberg
Date: Fri Oct 04 2019 - 04:20:02 EST


On Fri, Oct 04, 2019 at 11:07:34AM +0300, Yehezkel Bernat wrote:
> > Also if you can get the hw_vendor_id and hw_product_id from the kernel
> > does that mean you don't need to do the two reads or you still need
> > those?
>
> Are those the chip vendor or the OEM, in case they are different?

Those are the actual USB4 hardware maker values, directly from
ROUTER_CS_0 (p. 287 in the USB4 spec). This almost certainly differ from
the OEM values from DROM we currently expose.

> Thinking about it again, I'd guess it shouldn't matter much, if the chip is from
> Intel, the FW supports NVM upgrade, isn't it?

So the bottom line is that if the kernel thinks the router supports NVM
upgrade it exposes the nvm_active/nvm_non_active files etc. I think
fwupd uses this information to display user whether the device can be
upgraded or not (for example ICL cannot as the NVM is part of BIOS).

Exposing hw_vendor_id and hw_product_id may speed up fwupd because it
does not need to go over the active NVM to figure out whether the new
image is for the correct controller.