> Currently, we don't have any phy drivers. Generic driver doesn't seems to
> support 2500Mbps.
Correct. genphy only supports upto 1G. The c45 based genphy_c45 is
slowly gaining more features and might soon support 2.5G.
> If I have to write the driver, whether it is necessary for
> phy device to advertise speed of 2500Mbps?
The user could force it, using the ethool command you suggested. But
it is the PHY driver which configures this. If you add the driver code
to force it, you might as well add the driver code to allow it to be
negotiated.
> Phy is custom phy and is currently under test. If you know any phy device
> that supports 2500Mbps and whose data sheet is available freely please let
> me know.
There are none that i know of with open data sheets. However the IEEE
standards should be freely available and they describe the registers
the PHY is expected to have. There are also patches floating around
which add 2.5G and 5G support to the marvell10g driver. I expect these
patches to get merged soon, but maybe in a different form to make
genphy_c45 more generic.
Andrew
