[PATCH v2 7/8] net: mvmdio: add xmdio support

Andrew Lunn andrew at lunn.ch
Thu Jun 8 09:55:46 PDT 2017


On Thu, Jun 08, 2017 at 09:42:21AM -0700, Florian Fainelli wrote:
> On 06/08/2017 02:26 AM, Antoine Tenart wrote:
> > This patch adds the xMDIO interface support in the mvmdio driver. This
> > interface is used in Ethernet controllers on Marvell 370, 7k and 8k (as
> > of now). The xSMI interface supported by this driver complies with the
> > IEEE 802.3 clause 45 (while the SMI interface complies with the clause
> > 22). The xSMI interface is used by 10GbE devices.
> 
> In the previous version you were properly defining a new compatibles
> strings for xmdio, but now you don't and instead you runtime select the
> operations based on whether MII_ADDR_C45 is set in the register which is
> fine from a functional perspective.
> 
> If I get this right, the xMDIO controller is actually a superset of the
> MDIO controller and has an extra MVMDIO_XSMI_ADDR_REG register to
> preform C45 accesses?
> 
> If that is the case (and looking at patch 8 that seems to be the case),
> you probably still need to define a new compatible string for that
> block, because it has a different register layout than its predecessor.

Yes, i think you need the compatible string to return -EOPNOSUP when
somebody tries to do a C45 access on the older IP which only has C22.

	 Andrew



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