> G4 powermac (dmesg below) which has 4.7 (although it looks like the > drivers in this case haven't changed). > > Short version: > The gem manpage claims 10Mbit half-duplex (or full, but I didn't try > that), but it clearly does not. Why? No idea. I've done some cursory > looking through the files for gem and brgphy and can't find anything > mentioning a quirk of the Apple gem. (Which at least would be a bug in > the manpage, since it says it is supported and doesn't mention any > exceptions).
gem(4) media support is limited by the PHY it is connected to. Your machine has a particular brgphy(4) model which can only do 100Mb/s and 1Gb/s. I have a gem(4) here connected to a bmtphy(4), which can do 10Mb/s and runs fine in that configuration. Miod
