On Thu, Apr 19, 2018 at 04:47:23PM -0500, Bjorn Helgaas wrote: > I *thought* the hardware was supposed to automatically negotiate to > the highest rate supported by both sides without any help at all from > software. But since several drivers have code to do it themselves, I > wonder if I'm missing something, or maybe there's something the PCI > core should be doing that it isn't, and the driver code is basically > working around that PCI core deficiency. The HW is supposed to do that, but Gen3 is electrically *hard*. I'm not surprised that some HW has run into trouble where the driver might have to be involved to tweak the SERDES.. eg there is now often on-device software involved here and updating the SERDES 'firmware' may be needed. Jason
