05-02-2014 12:35 AM
xapp1026 states that "lwIP includes software to detect the PHY speed, however this software works only for Marvell PHYs.".
How does it work and how can we add other phys for this feature, especially for Micrel phys?
05-02-2014 04:35 AM
There are a few customers who were able to get Micrel PHY working.
There are only few files within LWIP which are dependent on the Marvel PHY. So you can edit the LWIP source in the same locations.
05-03-2014 05:14 AM
Did you check the source code?
Nothing in the driver code appears to be specific to Marvell PHYs. In fact, in older versions of the library, the code does not check the PHY identifier, it simply reads/writes the IEEE standard registers.
For some reason that I do not understand, in newer versions of the library, the code specifically checks for Marvell PHYs, if it can't find any, it doesn't even attempt to autonegotiate, even though it is only reading/writing standard IEEE registers which are also supported in a Micrel PHY (at least for GMII interface, for example KSZ9031MNX).
What is it with Micrel PHYs that Xilinx/LWIP explicitly removed support for autonegotiation? Is there something wrong with the chips?