I believe that's what I said. The hard disk controller is a chip packaged with the hard drive. The CPU talks to the hard disk controller to get data from the disk, with IDE commands or something like that.

I think controllers used to be dedicated circuitry, but now they are more like CPUs with firmware.

http://en.wikipedia.org/wiki/Disk_controller

http://en.wikipedia.org/wiki/Controller_(computing)

In a modern computer, there are dozens of these little chips, each having security implications. Nobody knows the provenance of all the code since they are mostly manufactured overseas.

Oh, when you said "hard disk controller" I thought at first you meant the SATA bus master.

> But, oddly enough, I have yet to hear anyone calling for open-source hard drives...

Fruitless debates about HDD firmware (and many more) are an undying hobby of some people in the wider coreboot community. These days the topic comes up every week or two.