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Archit Taneja d68fe15b18 drm/msm/mdp5: Use runtime PM get/put API instead of toggling clocks
mdp5_enable/disable calls are scattered all around in the MDP5 code.
Use the pm_runtime_get/put calls here instead, and populate the
runtime PM suspend/resume ops to manage the clocks.

About the overall design: MDP5 is a child of the top level MDSS
device. MDSS is also the parent to DSI, HDMI and other interfaces. When
we enable MDP5's power domain, we end up enabling MDSS's PD too. It is
only MDSS's PD that actually controlls the GDSC HW. Therefore, calling
runtime_get/put on the MDP5 device is like just requesting a vote to
enable/disable the GDSC.

Functionally, replacing the clock enable/disable calls with the RPM API
can result in the power domain (GDSC) state being toggled if no other
child isn't powered on. This can result in the register context being lost.
We make sure (in future commits) that code paths don't end up configuring
registers and then later lose state, resulting in a bad HW state.

For now, we've replaced each mdp5_enable/disable with runtime_get/put API.
We could optimize things later by removing runtime_get/put calls which
don't really need to be there. This could prevent unnecessary toggling of
the power domain and clocks.

Signed-off-by: Archit Taneja <architt@codeaurora.org>
Signed-off-by: Rob Clark <robdclark@gmail.com>
2017-08-02 07:53:46 -04:00
arch Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-07-30 12:19:35 -07:00
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drivers drm/msm/mdp5: Use runtime PM get/put API instead of toggling clocks 2017-08-02 07:53:46 -04:00
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include drm/msm: Remove __user from __u64 data types 2017-08-01 19:11:48 -04:00
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kernel Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-07-30 11:54:08 -07:00
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Makefile Linux 4.13-rc3 2017-07-30 12:40:36 -07:00
README

Linux kernel
============

This file was moved to Documentation/admin-guide/README.rst

Please notice that there are several guides for kernel developers and users.
These guides can be rendered in a number of formats, like HTML and PDF.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.