I was familiar with clean room because I was once part of such a project. I was aware nVidia drivers had parts that they considered to be "secret sauce" algorithms (and ATI didn't?). From what you said, I'm assuming it was the firmware which must be loaded onto the card?
I'm only vaguely familiar with the requirements for HDCP compliance, but I'm guessing that safeguarding keys is part of it. So, my assumption is that nVidia needed to do that, in general, rather than to specifically make it difficult for the nouveau project.
Perhaps, the libdvdcss approach by players will work. The players don't have de-CSS capabilities themselves, but they do look around for the lib. If it "happens to be around" (e.g. liability is shifted to the end user who downloaded it separately), they will use it.
In other words, you always need the card, so everything else is protected without needing specific protection of its own.
My answer to all that is that nVidia cards are mostly software nowadays (except for the real rendering/computing core). Nvidia uses a common ISA for most engines. It was reversed engineered when Fermi was out and took more than a year before we wrote our core firmwares by ourselves. I'm currently writing the hardware monitoring firmware as a first experience with this ISA.
These firmwares execute on harvard "microcontrolers" and all have some special capabilities depending on the engine they run on.
The firmwares themselves aren't secure at all and aren't meant to be anyway. However, some "memory pages" can be marked as secret so as you can't access them from the host unless you know the "password". I never studied this part, if you are interested, you can read what has already been documented: https://github.com/pathscale/envytools/blob/master/hwdocs/fuc-vm.txt
In the end, the card itself isn't particularly needed since it is mostly software and we should be able to fake many things. But what's the point of hdcp anyway?
Another assurance for nVidia is that they know how slow going the RE is, compared to what they can do. They'll always be several steps ahead, no matter what. So, nouveau is no "threat" to them. The only people they're really concerned about are competitors like AMD/ATI and Intel that make HW.
Right, by the time the hw is shipped, nVidia doesn't worry anymore about their secrets. Nouveau is thus not a problem for them. However, yesterday, the 3d driver for Kepler was released, less than a month after the release of the first Kepler GPU. Some people in the Nouveau really are in-human :D
Be thankful you're in Europe. In the US, the RIAA has been known to sue widows and orphans :-)
Yeah, the US is always crazy about IP. Can't wait for the whole damn thing be to reformed to be friendlier with those who really do make the country go forward.
