linux-phytec-ti

phy: keystone: serdes driver for 1gbe, 10gbe and pcie

On TI's Keystone platforms, several peripherals such as the
gbe ethernet switch, 10gbe ethernet switch and PCIe controller
require the use of a SerDes for converting SoC parallel data into
serialized data that can be output over a high-speed electrical
interface, and also converting high-speed serial input data
into parallel data that can be processed by the SoC.  The
SerDeses used by those peripherals, though they may be different,
are largely similar in functionality and setup.

This patch provides a SerDes phy driver implementation that can be
used by the above mentioned peripheral drivers to configure their
respective SerDeses.

The SerDes configurations are divided mainly in two parts, namely,
a common configuration which is done regardless a SerDes lane is
actually used or not, and a lane specific configuration which is
done when a lane is actually used by, for example, a network interface.

The common configuration is performed by the SerDes provider
driver, ie., phy-keystone-serdes.c, at driver probe. The lane
specific configuration is invoked by the corresponding peripheral
driver, for example network switch driver, through the PHY API.

The SerDes IP is owned by a 3rd party and this patch uses no comments
in the driver as recommended by the vendor. Also the license header
used in the file is in accordance with the vendor's recommendation
of using BSD license for the driver file.

Signed-off-by: WingMan Kwok <w-kwok2@ti.com>
Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
Signed-off-by: Jack Manbeck <j-manbeck2@ti.com>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>