mvebu: cp110: avoid pcie power on/off sequence when called from Linux ...

In Armada 8K DB boards, PCIe initialization can be executed only once
because PCIe reset performed during chip power on and it cannot be
executed via GPIO later.
This means that power on can be executed only once, when it's called
from the bootloader.
Power on:
	Read bit 21 of the mode, it marks if the caller is
	the bootloader or the Linux Kernel.
Power off:
	Check if the comphy was already configured to PCIe, if yes,
	check if the caller is bootloader, if both conditions are true
	(PCIe mode and called by Linux) - skip the power-off.

In addition, fix incorrect documentation describing mode fields -
PCIe width is 3 bits, not 2.

NOTE: with this patch, please use LK4.14.76 (LK4.4.120 may not work
with it).

Change-Id: I4b929011f97a0a1869a51ba378687e78b3eca4ff
Signed-off-by: Igal Liberman <igall@marvell.com>
Reviewed-by: Grzegorz Jaszczyk <jaz@semihalf.com>
Reviewed-by: Kostya Porotchkin <kostap@marvell.com>

Standardise header guards across codebase ...

All identifiers, regardless of use, that start with two underscores are
reserved. This means they can't be used in header guards.

The style that this project is now to use the full name of the file in
capital letters followed by 'H'. For example, for a file called
"uart_example.h", the header guard is UART_EXAMPLE_H.

The exceptions are files that are imported from other projects:

- CryptoCell driver
- dt-bindings folders
- zlib headers

Change-Id: I50561bf6c88b491ec440d0c8385c74650f3c106e
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

mvebu: cp110: introduce COMPHY porting layer ...

Some of COMPHY parameters depends on the hw connection between the SoC
and the PHY, which can vary on different boards e.g. due to different
wires length. Define the "porting layer" with some defaults
parameters. It ease updating static values which needs to be updated due
to board differences, which are now grouped in one place.

Example porting layer for a8k-db is under:
plat/marvell/a8k/a80x0/board/phy-porting-layer.h

If for some boards parameters are not defined (missing
phy-porting-layer.h), the default values are used
(drivers/marvell/comphy/phy-default-porting-layer.h)
and the following compilation warning is show:
"Using default comphy params - you may need to suit them to your board".

The common COMPHY driver code is extracted in order to be shared with
future COMPHY driver for A3700 SoC platforms

Signed-off-by: Grzegorz Jaszczyk <jaz@semihalf.com>
Signed-off-by: Igal Liberman <igall@marvell.com>
Signed-off-by: Konstantin Porotchkin <kostap@marvell.com>