[RFC PATCH 0/7] Add driver for dvfsrc and add support for active state of scpsys on mt8183

From: Henry Chen
Date: Wed Jan 02 2019 - 09:01:08 EST

The patchsets add support for MediaTek hardware module named DVFSRC
(dynamic voltage and frequency scaling resource collector). The DVFSRC is
a HW module which is used to collect all the requests from both software
and hardware and turn into the decision of minimum operating voltage and
minimum DRAM frequency to fulfill those requests.

So, This series is to implement the dvfsrc driver to collect all the
requests of operating voltage or DRAM bandwidth from other device drivers
likes GPU/Camera through 2 frameworks basically:

1. PM_QOS_MEMORY_BANDWIDTH from PM QOS: to aggregate the bandwidth
requirements from different clients
2. Active state management of power domains[1]: to handle the operating
voltage opp requirement from different power domains

[1] https://lwn.net/Articles/744047/