Go to file
Dhinakaran Pandiyan 2e8bf223d8 drm/i915: Estimate and update missed vblanks.
The frame counter may have got reset between disabling and enabling vblank
interrupts due to DMC putting the hardware to DC5/6 states if PSR was
active. The frame counter could also have stalled if PSR was active in case
there was no DMC. The frame counter resetting has a user visible impact
of screen freezes.

Make use of drm_vblank_restore() to compute missed vblanks for the duration
in which vblank interrupts were disabled and update the vblank counter with
this value as diff. There's no need to check if PSR was actually active in
the interrupt disabled duration, so simplify the check to a feature check.

Enabling vblank interrupts wakes up the hardware from DC5/6 and prevents it
from going back again as long as the there are pending interrupts. So, we
don't have to explicity disallow DC5/6 after enabling vblank interrupts to
keep the counter running.

This change is not applicable to CHV, as enabling interrupts does not
prevent the hardware from activating PSR.

v2: Added comments(Rodrigo) and rewrote commit message.

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180203051302.9974-10-dhinakaran.pandiyan@intel.com
2018-02-15 11:50:22 -08:00
arch Linux 4.15-rc8 2018-01-18 09:32:15 +10:00
block
certs
crypto Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2018-01-12 09:47:58 -08:00
Documentation Linux 4.15-rc8 2018-01-18 09:32:15 +10:00
drivers drm/i915: Estimate and update missed vblanks. 2018-02-15 11:50:22 -08:00
firmware
fs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2018-01-06 17:13:21 -08:00
include drm/vblank: Restoring vblank counts after device PM events. 2018-02-15 11:50:14 -08:00
init Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-01-12 10:23:59 -08:00
ipc
kernel Merge branch 'akpm' (patches from Andrew) 2018-01-13 11:07:55 -08:00
lib Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf 2018-01-10 11:17:21 -05:00
mm kmemleak: allow to coexist with fault injection 2018-01-13 10:42:48 -08:00
net Char/Misc fixes for 4.15-rc8 2018-01-13 14:01:59 -08:00
samples
scripts Kbuild fixes for v4.15 2018-01-13 13:24:56 -08:00
security Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-01-14 09:51:25 -08:00
sound ALSA: pcm: Allow aborting mutex lock at OSS read/write loops 2018-01-08 16:40:26 +01:00
tools Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-01-14 09:51:25 -08:00
usr
virt
.cocciconfig
.get_maintainer.ignore
.gitattributes
.gitignore
.mailmap
COPYING
CREDITS
Kbuild
Kconfig
MAINTAINERS Linux 4.15-rc8 2018-01-18 09:32:15 +10:00
Makefile Linux 4.15-rc8 2018-01-14 15:32:30 -08:00
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.