net: ti: icssg-prueth: am65x SR2.0 add 10M full duplex support

For AM65x SR2.0 it's required to enable IEP1 in raw 64bit mode which is
used by PRU FW to monitor the link and apply w/a for 10M link issue.
Note. No public errata available yet.

Without this w/a the PRU FW will stuck if link state changes under TX
traffic pressure.

Hence, add support for 10M full duplex for AM65x SR2.0:
- add new IEP API to enable IEP, but without PTP support
- add pdata quirk_10m_link_issue to enable 10M link issue w/a.

Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Reviewed-by: Roger Quadros <rogerq@kernel.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: MD Danish Anwar <danishanwar@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: ti: icssg-prueth: add packet timestamping and ptp support

Add packet timestamping TS and PTP PHC clock support.

For AM65x and AM64x:
- IEP1 is not used
- IEP0 is configured in shadow mode with 1ms cycle and shared between
Linux and FW. It provides time and TS in number cycles, so special
conversation in ns is required.
- IEP0 shared between PRUeth ports.
- IEP0 supports PPS, periodic output.
- IEP0 settime() and enabling PPS required FW interraction.
- RX TS provided with each packet in CPPI5 descriptor.
- TX TS returned through separate ICSSG hw queues for each port. TX TS
readiness is signaled by INTC IRQ. Only one packet at time can be requested
for TX TS.

Signed-off-by: Roger Quadros <rogerq@ti.com>
Co-developed-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: MD Danish Anwar <danishanwar@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: ti: icss-iep: Add IEP driver

Add a driver for Industrial Ethernet Peripheral (IEP) block of PRUSS to
support timestamping of ethernet packets and thus support PTP and PPS
for PRU ethernet ports.

Signed-off-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: MD Danish Anwar <danishanwar@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>