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Any example will do. Thanks, > > The PCI core is going to perform CMA/SPDM authentication when a device > gets enumerated (PCIe r6.0 sec 6.31). That's the main motivation > to lift DOE mailbox creation into the PCI core. It's not mentioned > here explicitly because I want the patch to stand on its own. > CMA/SPDM support will be submitted separately. I was going the opposite direction with avoiding adding this into the PCI core as 1) the pci_dev struct is already 2K and 2) it is a niche feature and 3) I wanted this CMA/SPDM session setup to be platform specific as on our platform the SPDM support requires some devices to be probed before we can any SPDM. > A driver that later on gets bound to the device should be allowed > to talk to it via DOE as well, possibly even sharing the same DOE > mailboxes used by the PCI core. > > Patches for CMA/SPDM are under development on this branch: > > https://github.com/l1k/linux/commits/doe yes, thanks! Lots of reading :) >>> Currently a DOE instance cannot be shared by multiple drivers because >>> each driver creates its own pci_doe_mb struct for a given DOE instance. >> >> Sorry for my ignorance but why/how/when would a device have multiple drivers >> bound? Or it only one driver at the time but we also want DOE MBs to survive >> switching to another (different or newer) driver? > > Conceivably, a driver may have the need to talk to multiple devices > via DOE, even ones it's not bound to. (E.g. devices in its ancestry > or children.) Ah ok. Well, a parent device could look for the DOE MB in a child using devres_find(), this requirement alone does not require moving things to the PCI core and potentially allows it to be a module which could be a better way as distros could have it always enabled but it would not waste any memory on my laptop when not loaded. Thanks, -- Alexey