supports DRM functions and may not be fully accessible
There’s an extension of the ATA protocol (the “language” spoken between your mainboard and your SATA SSDs), which allows for the storage device to reply differently, depending on whether a request was signed by the trusted platform module on the mainboard. That way, things like video player devices that only give access to the stored data when the software has proven itself to be unmodified can be implemented. (I can find much more interesting use cases, but digital rights management seems to be what the kernel authors saw as the application for this when they implemented that warning.) That also means that Linux might simply get an “incomplete” view of the SSD, hence it warns you about that, in case you wonder.
read cache: enabled, doesn’t support DPO or FUA
uff, this just tells you that the device has a read cache: the computer fetches some smaller unit of data, and the device keeps that (and potentially more of its surroundings) around in a smaller, faster “transparent” piece of memory. That makes sense, because it’s more common that data that was recently read is read again than some data that nobody cared about for a long time.
DPO and FUA are just really old techniques to tell SCSI (and consequently, ATAPI) devices to bypass that cache (FUA was supposed to force reading from the spinning platter without using what’s in the cache, whereas DPO was meant to say, hey, this is probably a one-off read; don’t care to start caching what I read here). Makes no sense for an SSD in how they were thought out in the early 1990s, so these extensions are not available for your SSD.
