Session

One of the techniques Ethernet uses to achieve a high rate of speed is pulse-amplitude modulation. This allows increasing the density of the data being sent by a signal by defining equalization ranges for different combinations of bits. These ranges differ based on speed and are configured in firmware before the link is up.

Ranges are typically defined in firmware and seldom changed. However during hardware interoperability testing they must be evaluated, tested, and potentially modified. Testing requires manually starting and stopping pseudo random binary sequence(PRBS) modes and other indefinite pattern tests. Various vendors provide their own proprietary tools to set equalization values and run pattern tests. No open source tool exists to provide this functionality.

At the Netdev 0x18 - Driver and H/W APIs Workshop the community discussed various methods to implement new common features. The community acknowledged that the kernel must never break user space and only accept new features once they have matured enough to become a standard interface. The purpose of this talk is to discuss whether setting equalization values and enabling pattern tests has matured enough across various vendors to develop a standard open source interface.