Linux mainline fork with MSM8998 patches | https://mainline.space | Currently supported devices: OnePlus 5/5T, Xiaomi Mi 6, F(x)tec Pro¹ (2019 QX1000 model) & Sony Xperia XZ Premium (UNTESTED!)
Find a file
Ville Syrjälä f22f4e5be8 drm/i915: Stop force enabling pipe bottom color gammma/csc
While sanitizing the hardware state we're currently forcing
the pipe bottom color legacy csc/gamma bits on. That is not a
good idea as BIOSen are likely to leave gabage in the LUTs and
so doing this causes ugly visual glitches if and when the
planes covering the background get disabled. This was exactly
the case on this Dell Precision 5560 tgl laptop.

On icl+ we don't normally even use these legacy bits
anymore and instead use their GAMMA_MODE counterparts.
On earlier platforms the bits are used, but we still
shouldn't force them on without knowing what's in the LUT.

So two options, get rid of the whole thing, or do what
intel_color_commit() does to make sure the bottom color state
matches whatever out hardware readout produced. I chose the
latter since it'll match what happens on older platforms when
the primary plane gets turned off. In fact let's just call
intel_color_commit(). It'll also do some CSC programming but
since we don't have readout for that it'll actually just set
to all zeros. So in the unlikely case of CSC actually being
enabld by the BIOS we'll end up with all black until the first
atomic commit happens.

Still not totally sure what we should do about color management
features here in general. Probably the safest  thing would be to
force everything off exactly at the same time when we disable
the primary plane as there is no guarantees that whatever the
LUTs/CSCs contain make any sense whatsoever without the
specific pixel data in the BIOS fb. And if we preserve the
primary plane then we should disable the color management
features exactly when the primary plane fb contents first
changes since the new content assumes more or less no
transformations. But of course synchronizing front buffer
rendering with anything else is a bit hard...

Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/3534
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210928185105.3030-1-ville.syrjala@linux.intel.com
Reviewed-by: Uma Shankar <uma.shankar@intel.com>
2021-10-01 20:46:30 +03:00
arch Updates for the SMP and CPU hotplug: 2021-09-12 12:42:51 -07:00
block block-5.15-2021-09-11 2021-09-11 10:19:51 -07:00
certs certs: Add support for using elliptic curve keys for signing modules 2021-08-23 19:55:42 +03:00
crypto Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2021-08-30 12:57:10 -07:00
Documentation Merge drm/drm-next into drm-intel-next 2021-09-15 10:12:51 -04:00
drivers drm/i915: Stop force enabling pipe bottom color gammma/csc 2021-10-01 20:46:30 +03:00
fs Merge branch 'misc.namei' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2021-09-12 10:43:51 -07:00
include drm/dp: add helper for extracting adjust 128b/132b TX FFE preset 2021-09-20 18:45:35 +03:00
init More tracing updates for 5.15: 2021-09-09 13:11:15 -07:00
ipc ARM development updates for 5.15: 2021-09-09 13:25:49 -07:00
kernel - Make sure the idle timer expires in hardirq context, on PREEMPT_RT 2021-09-12 11:37:41 -07:00
lib Minor fixes to the processing of the bootconfig tree. 2021-09-11 10:16:30 -07:00
LICENSES LICENSES/dual/CC-BY-4.0: Git rid of "smart quotes" 2021-07-15 06:31:24 -06:00
mm ARM development updates for 5.15: 2021-09-09 13:25:49 -07:00
net virtio,vdpa,vhost: features, fixes 2021-09-11 14:48:42 -07:00
samples kgdb patches for 5.15 2021-09-07 12:08:04 -07:00
scripts RISC-V Patches for the 5.15 Merge Window, Part 2 2021-09-11 14:29:42 -07:00
security Kbuild updates for v5.15 2021-09-03 15:33:47 -07:00
sound sound fixes for 5.15-rc1 2021-09-09 16:05:10 -07:00
tools perf tools changes for v5.15: 2nd batch 2021-09-12 16:18:15 -07:00
usr .gitignore: prefix local generated files with a slash 2021-05-02 00:43:35 +09:00
virt KVM: Drop unused kvm_dirty_gfn_invalid() 2021-09-06 08:23:46 -04:00
.clang-format clang-format: Update with the latest for_each macro list 2021-05-12 23:32:39 +02:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore .gitignore: ignore only top-level modules.builtin 2021-05-02 00:43:35 +09:00
.mailmap mailmap: update email address of Matthias Fuchs and Thomas Körper 2021-08-19 09:39:44 +02:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: move Murali Karicheri to credits 2021-04-29 15:47:30 -07:00
Kbuild kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS Compiler Attributes improvements: 2021-09-12 16:09:26 -07:00
Makefile Linux 5.15-rc1 2021-09-12 16:28:37 -07:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

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

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

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.