bcf3440c6d
Add support for following phy-modes: rgmii, rgmii-id, rgmii-txid, rgmii-rxid. This PHY has an internal RX delay of 1.2ns and no delay for TX. The pad skew registers allow to set the total TX delay to max 1.38ns and the total RX delay to max of 2.58ns (configurable 1.38ns + build in 1.2ns) and a minimal delay of 0ns. According to the RGMII v1.3 specification the delay provided by PCB traces should be between 1.5ns and 2.0ns. The RGMII v2.0 allows to provide this delay by MAC or PHY. So, we configure this PHY to the best values we can get by this HW: TX delay to 1.38ns (max supported value) and RX delay to 1.80ns (best calculated delay) The phy-modes can still be fine tuned/overwritten by *-skew-ps device tree properties described in: Documentation/devicetree/bindings/net/micrel-ksz90x1.txt Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de> Reviewed-by: Philippe Schenker <philippe.schenker@toradex.com> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.