No description
  • C 96.9%
  • Assembly 0.9%
  • Rust 0.6%
  • Shell 0.6%
  • Python 0.5%
  • Other 0.3%
Find a file
Nicholas Kazlauskas 737b2b536a drm/amd/display: Fix MPC OGAM power on/off sequence
[Why]
Color corruption can occur on bootup into a login
manager that applies a non-linear gamma LUT because
the LUT may not actually be powered on before writing.

It's cleared on the next full pipe reprogramming as
we switch to LUTB from LUTA and the pipe accessing
the LUT has taken it out of light sleep mode.

[How]
The MPCC_OGAM_MEM_PWR_FORCE register does not force
the current power mode when set to 0. It only forces
when set light sleep, deep sleep or shutdown.

The register to actually force power on and ignore
sleep modes is MPCC_OGAM_MEM_PWR_DIS - a value of 0
will enable power requests and a value of 1 will
disable them.

When PWR_FORCE!=0 is combined with PWR_DIS=0 then
MPCC OGAM memory is forced into the state specified
by the force bits.

If PWR_FORCE is 0 then it respects the mode specified
by MPCC_OGAM_MEM_LOW_PWR_MODE if the RAM LUT is not
in use.

We set that bit to shutdown on low power, but otherwise
it inherits from bootup defaults.

So for the fix:

1. Update the sequence to "force" power on when needed

We can use MPCC_OGAM_MEM_PWR_DIS for this to turn on the
memory even when the block is in bypass and pending to be
enabled for the next frame.

We need this for both low power enabled or disabled.

If we don't set this then we can run into issues when we
first program the LUT from bootup.

2. Don't apply FORCE_SEL

Once we enable power requests with DIS=0 we run into the
issue of the RAM being forced into light sleep and being
unusable for display output. Leave this 0 like we used to
for DCN20.

3. Rely on MPCC OGAM init to determine light sleep/deep sleep

MPC low power debug mode isn't enabled on any ASIC currently
but we'll respect the setting determined during init if it
is.

Lightly tested as working with IGT tests and desktop color
adjustment.

4. Change the MPC resource default for DCN30

It was interleaving the dcn20 and dcn30 versions before
depending on the sequence.

5. REG_WAIT for it to be on whenever we're powering up the
memory

Otherwise we can write register values too early and we'll
get corruption.

Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Reviewed-by: Eric Yang <eric.yang2@amd.com>
Acked-by: Qingqing Zhuo <Qingqing.Zhuo@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
History 2021-02-18 16:43:10 -05:00
arch Linux 5.11-rc5 2021-01-25 14:35:44 +10:00
block block-5.11-2021-01-10 2021-01-10 12:53:08 -08:00
certs .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
crypto X.509: Fix crash caused by NULL pointer 2021-01-20 11:33:51 -08:00
Documentation Mediatek DRM Next for Linux 5.12 2021-02-05 09:25:26 +10:00
drivers drm/amd/display: Fix MPC OGAM power on/off sequence 2021-02-18 16:43:10 -05:00
fs io_uring-5.11-2021-01-24 2021-01-24 12:30:14 -08:00
include Mediatek DRM Next for Linux 5.12 2021-02-05 09:25:26 +10:00
init Revert "init/console: Use ttynull as a fallback when there is no console" 2021-01-08 11:02:18 -08:00
ipc Merge branch 'akpm' (patches from Andrew) 2020-12-15 12:53:37 -08:00
kernel - Fix a kernel panic in mips-cpu due to invalid irq domain hierarchy. 2021-01-24 10:24:20 -08:00
lib ubsan: disable unsigned-overflow check for i386 2021-01-24 10:34:52 -08:00
LICENSES LICENSES: Add the CC-BY-4.0 license 2020-12-08 10:33:27 -07:00
mm mm/highmem: prepare for overriding set_pte_at() 2021-01-24 10:34:52 -08:00
net A patch to zero out sensitive cryptographic data and two minor cleanups 2021-01-22 13:47:25 -08:00
samples ARM: SoC drivers for v5.11 2020-12-16 16:38:41 -08:00
scripts Kbuild fixes for v5.11 2021-01-10 13:24:55 -08:00
security dump_common_audit_data(): fix racy accesses to ->d_name 2021-01-16 15:11:35 -05:00
sound ALSA: usb-audio: Fix hw constraints dependencies 2021-01-20 21:46:45 +01:00
tools - Adjust objtool to handle a recent binutils change to not generate unused 2021-01-24 10:17:03 -08:00
usr Merge branch 'work.fdpic' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-08-07 13:29:39 -07:00
virt x86: 2021-01-08 15:06:02 -08:00
.clang-format RDMA 5.10 pull request 2020-10-17 11:18:18 -07:00
.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: docs: ignore sphinx_*/ directories 2020-09-10 10:44:31 -06:00
.mailmap MAINTAINERS: Update my email address 2021-01-15 23:55:16 +01:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: dccp: move Gerrit Renker to CREDITS 2021-01-14 10:53:49 -08:00
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 Linux 5.11-rc5 2021-01-25 14:35:44 +10:00
Makefile Linux 5.11-rc5 2021-01-24 16:47:14 -08:00
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.