On 11/28/2016 06:14 AM, Andrew Lunn wrote: > On Mon, Nov 28, 2016 at 02:24:30PM +0100, Allan W. Nielsen wrote: >> From: Raju Lakkaraju <raju.lakkar...@microsemi.com> >> >> 3 types of PHY loopback are supported. >> i.e. Near-End Loopback, Far-End Loopback and External Loopback. > > Hi Allan > > Is this integrated with ethtool --test? You only want the PHY to go > into loopback mode when running ethtool --test external_lb or maybe > ethtool --test offline. > > What i think should happen is that this tunable sets the mode the PHY > will go into when loopback is enabled. It does not however enable > loopback. It is running ethtool --test which actually enables the > loopback, probably by setting BMCR_LOOPBACK. Once the test is > finished, the bit is cleared and the PHY goes back into normal > operation.
Agreed with Andrew, there needs to be a tight coupling between the existing ethtool test infrastructure, and how to perform PHY loopback testing. It makes sense for the PHY drivers to be able to implement specific loopback/test mode, but we need to clarify how these get called from ethtool --test for instance, and if the Ethernet MAC driver needs to do something specific as well. -- Florian
