On Sun, Jan 10, 2021 at 11:13:44AM +0000, Russell King wrote: > This allows network drivers such as mvpp2 to use their more accurate > timestamping implementation than using a less accurate implementation > in the PHY. Network drivers can opt to defer to phylib by returning > -EOPNOTSUPP.
My expectation is that PHY time stamping is more accurate than MAC time stamping. > This change will be needed if the Marvell PHY drivers add support for > PTP. Huh? The mvpp2 appears to be a MAC. If this device has integrated PHYs then I don't see the issue. If your board has the nvpp2 device with the dp83640 PHYTER, then don't you want to actually use the PHYTER? >From my observation of the product offerings, I have yet to see a new PHY (besides the dp83640 PHYTER) that implement time stamping. The PHYTER is 100 megabit only, and my understanding that it is too difficult or even impossible to provide time stamps from within a gigabit+ PHY. So you needn't fear new time stamping PHYs to spoil your setup! > Note: this may cause a change for any drivers that use phylib and > provide get_ts_info(). It is not obvious if any such cases exist. Up until now, the code always favored PHY devices and devices external to the MAC that snoop on the MII bus. The assumption is that anyone who builds a board with such specialty devices really wants to use them. Thanks, Richard
