MFC r320159:
Add the ofw_bus_get_node() callback in mv_twsi, it is mandatory for the
ofw_iicbus usage.

Sponsored by: Rubicon Communications, LLC (Netgate)

Copy head@r302406 to stable/11 as part of the 11.0-RELEASE cycle.
Prune svn:mergeinfo from the new branch, as nothing has been merged
here.

Additional commits post-branch will follow.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Fix the spelling of OF_getencprop. It will fix the data correctly for the
endian of the CPU so there is no need to call fdt32_to_cpu.

Sponsored by: ABT Systems Ltd

Add support for the Allwinner i2c device. This is similar to the existing
Marvell twsi part, however uses different register locations, as such split
the existing driver into Marvell and Allwinner attachments.

While here clean a few style issues.

Submitted by: Emmanuel Vadot <manu@bidouilliste.com>
Differential Revision: https://reviews.freebsd.org/D4846

Move the twsi driver source to be under iicbus. It is in a separate
directory as it is expected multiple attachments will be added for the SoC
families that use this hardware.

Sponsored by: ABT Systems Ltd

Remove an unused include.

Stop adding an extra null terminator to strings, OF_getprop already returns
a null terminated string.

Add support for I2C on Armada38x

Extend driver's compatible strings' table
and enable I2C compilation in kernconf.

Reviewed by: andrew, ian
Obtained from: Semihalf
Sponsored by: Stormshield
Submitted by: Jan Dabros <jsd@semihalf.com>
Differential revision: https://reviews.freebsd.org/D4422

Follow r261352 by updating all drivers which are children of simplebus
to check the status property in their probe routines.

Simplebus used to only instantiate its children whose status="okay"
but that was improper behavior, fixed in r261352. Now that it doesn't
check anymore and probes all its children; the children all have to
do the check because really only the children know how to properly
interpret their status property strings.

Right now all existing drivers only understand "okay" versus something-
that's-not-okay, so they all use the new ofw_bus_status_okay() helper.

- Calculate the I2C baud rate to keep them <100 kHz under different TCLK
frequencies. The maximum freqency is 100 kHz according to the datasheet.

- Add child device probing support based on the device tree. It now tries to
find i2c-address property in the tree and attach the device with given slave
address to iicbus.

Convert Marvell ARM platforms to FDT convention.

The following systems are involved:

- DB-88F5182
- DB-88F5281
- DB-88F6281
- DB-78100
- SheevaPlug

This overhaul covers the following major changes:

- All integrated peripherals drivers for Marvell ARM SoC, which are
currently in the FreeBSD source tree are reworked and adjusted so they
derive config data out of the device tree blob (instead of hard coded /
tabelarized values).

- Since the common FDT infrastrucutre (fdtbus, simplebus) is used we say
good by to obio / mbus drivers and numerous hard-coded config data.

Note that world needs to be built WITH_FDT for the affected platforms.

Reviewed by: imp
Sponsored by: The FreeBSD Foundation.

strict kobj signatures: number of fixes for arm architecture

no functional changes should result

Reviewed by: imp, current@
Approved by: jhb (mentor)

Introduce basic support for Marvell families of system-on-chip ARM devices:

* Orion
- 88F5181
- 88F5182
- 88F5281

* Kirkwood
- 88F6281

* Discovery
- MV78100

The above families of SOCs are built around CPU cores compliant with ARMv5TE
instruction set architecture definition. They share a number of integrated
peripherals. This commit brings support for the following basic elements:

* GPIO
* Interrupt controller
* L1, L2 cache
* Timers, watchdog, RTC
* TWSI (I2C)
* UART

Other peripherals drivers will be introduced separately.

Reviewed by: imp, marcel, stass (Thanks guys!)
Obtained from: Marvell, Semihalf