[U-Boot] [PATCH V2 5/6] ARM: dts: k2g: Add support for PMMC

[Nishanth Menon <nm@ti.com>]

On Fri, Feb 26, 2016 at 12:18 PM, Tom Rini <trini@konsulko.com> wrote:
> On Thu, Feb 25, 2016 at 12:53:46PM -0600, Nishanth Menon wrote:
>
>> Enable support for PMMC the TI power processor on K2G. This processor
>> manages all power management related activities on the SoC and and
>> allows the Operating Systems on compute processors such as ARM, DSP to
>> offload the power logic away into the power processor. U-boot just has a
>> load responsibility, hence the view of the hardware from a bootloader
>> perspective is different from the view of hardware from a Operating
>> System perspective. While bootloader just loads up the firmware,
>> Operating Systems look at the resultant system as "hardware".
>>
>> Signed-off-by: Nishanth Menon <nm@ti.com>
>
> Reviewed-by: Tom Rini <trini@konsulko.com>
>
> ... and this will match whatever is in the kernel, right?

The Linux kernel will not need to access PMMC similar to how bootloader has to.

Bootloader looks to load up the peripheral - so, it's view of the
hardware is as a programmable core (similar to how we'd look at a
DSP/other remote proc), however, linux kernel only cares about the
communication link (which is the message manager) and the protocol on
top to communicate and does not need to access PMMC directly (it is
only done once by bootloader).

So the the current u-boot dt binding will not even need to be send
upstream kernel, instead a protocol level definition (similar to SCPI)
will be exposed to linux kernel.

-- 
---
Regards,
Nishanth Menon