Displayport to HDMI 2.1 adapters no longer working correctly on 6.4.12 works on 6.4.11

changed the description

Can you bisect? Can you also check if 6.5-rc7 and 6.5 final are affected?

@superm1 I can replicate the issue with my RX6700xt, arch linux, same display port adapter/cable but with LG C1.

After few kernel compilations git bisect claims this is the problematic commit:

commit dcfd5a3ecf91da0afc00ffa2ee0d20d65c45cfa5
Author: Daniel Miess <daniel.miess@amd.com>
Date:   Tue Apr 25 14:02:02 2023 -0400

drm/amd/display: Remove v_startup workaround for dcn3+

[ Upstream commit 3a31e8b89b7240d9a17ace8a1ed050bdcb560f9e ]

[Why]
Calls to dcn20_adjust_freesync_v_startup are no longer
needed as of dcn3+ and can cause underflow in some cases

[How]
Move calls to dcn20_adjust_freesync_v_startup up into
validate_bandwidth for dcn2.x

Reviewed-by: Jun Lei <jun.lei@amd.com>
Acked-by: Aurabindo Pillai <aurabindo.pillai@amd.com>
Signed-off-by: Daniel Miess <daniel.miess@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

.../gpu/drm/amd/display/dc/dml/dcn20/dcn20_fpu.c   | 24 ++++++++++++++++++----

mentioned in issue #1417

Thanks! Can you please cross reference against 6.5 final? If it works there we're probably missing another related backport.

@superm1 i will test - but 6.5rc6 and drm-next build on Aug 20 but had similar issues

with 6.4.12 i mainly get black screens or "No input" and with 6.5rc6 and drm-next i was getting "Invalid format"

both of this happen right from the moment modesetting gets enabled... so it seems to not be triggered by wayland/Xorg

@superm1 ok test done ... i compiled linux-stable master at commit 7d2f353b2682dcfe5f9bc71e5b61d5b61770d98e - same issue

then i did git revert -n dcfd5a3ecf91da0afc00ffa2ee0d20d65c45cfa5 and that fixes it, so it seems like at least for me that commit is pretty much what breaks it ...

now that i have all this setup - let me know if you want me to test any variations of that commit or anything else.

Got the latest 6.5 kernel from here https://aur.archlinux.org/packages/linux-drm-next-git and got the same issue as 6.4.12 not sure how I could revert that commit to see if it fixes the issue for me

@zany130 try with this file revert_dcfd5a3ecf91da0afc00ffa2ee0d20d65c45cfa5.diff

just do cat /path/to/that/file |patch -p1 while in the root kernel source dir/checkout ... no clue if it will apply to drm-next, but it applies for me on 6.4.12

if you are messing with the arch PKGBUILD ...there is a way to tell it to apply a patch before it builds, but remember being somewhat confusing.

Also until a developer responds... I'm for sure not daily driving it with this patch ... it was just an exercise to confirm that it is indeed the commit causing the issue for me.

Thanks, @gyordanov. I just wanted to check if 6.5 fixes it for me (and I didn't want to sit for an hour and build a kernel, so I got prebuilt packages from chaotic aur). I'll try to

git clone https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/

and then.

git revert -n dcfd5a3ecf91da0afc00ffa2ee0d20d65c45cfa5

I am guessing that would be enough to check if that commit is also the cause for me.

But yeah, I'm not planning on daily driving it as a fix... I will stick to 6.4.11 for now.

@zany130 yeah i dont think there is anything wrong with daily driving it, just I'll prefer if it gets fixed properly :)

as far as using the mainline repo - it should work, but i build my test from git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git

Did you guys confirm if just reverting that on top of 6.5 fixes it for your adapters?

@superm1 just compiled 6.5 with that commit reverted and all is working just fine.

Thanks. We unfortunately can't revert as that commit fixes some other problems so it's trading one issue for another. I've raised it with some internal folks to look at how to cover both cases.

@superm1 perfect - let me know if/when you guys need someone to test the new fix whenever there is a need ....

@gyordanov @zany130 Can you try the following patch? https://patchwork.freedesktop.org/patch/554998/

@effective-light it does not seem to apply cleanly on 6.5... should i test with drm-next or .. ?

It's applying to linus's tree (https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git). So, I guess you can try it on that.

Edit: It applies to linux-stable's linux-6.4.y branch (i.e. https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/?h=linux-6.4.y) as well so testing on that is probably a better idea.

@effective-light sorry it did apply, i messed up and somehow tried to patch it twice ... building now

Edit: will test with 6.5.0 first and then build 6.4.y just in case

@effective-light ok 6.5.0 works properly with that patch

@effective-light works just fine on linux-6.4.y too!

@effective-light works for me as well on 6.4.13

Is this on any stable Linux kernel yet, or should I stay on 6.4.11?

Just want to confirm that v6.6-rc1 fixed the issue of invalid format with this adapter (not the exact same adapter that @gyordanov uses, but likely the same hardware doing the DP -> HDMI conversion).

I had the same experience as @gyordanov, this initially worked on 6.4.11 and was broken by 6.4.12. Using a RX 6800XT with an LG C1.

Update 1: Seems like when waking from "Screen energy saving" (KDE terminology, not sure what this translates to in kernel-land) I get the "Invalid format" message on the display. Switching to another TTY and then back again seems to resolve the issue.

Update 2: Seems like the screen energy saving issue does not trigger every time.

However, 6.6-rc1 has another issue leading to a GPU reset ("ring sdma3 timeout"). I'll check out 6.4.12 with reverted dcfd5a3ecf91da0afc00ffa2ee0d20d65c45cfa5 and see if that works.

Update 3: 6.4.12 with reverted dcfd5a3ecf91da0afc00ffa2ee0d20d65c45cfa5 works well, with the exception of "Invalid format" being displayed immediately upon login (i.e. I assume that's when kwin starts). This was solved by switching TTYs and back again.

added DC label

added bisected label

added 6000 dGPU Series label

changed milestone to %linux-6.6

mentioned in commit agd5f/linux@38f38ea8

mentioned in commit agd5f/linux@63461ea3

mentioned in commit agd5f/linux@a81de4a2

The fixes for this are landed in 6.6-rc1 and they are CC stable and will trickle back.

closed

mentioned in commit nouveau@cc502fe1

Displayport to HDMI 2.1 adapters no longer working correctly on 6.4.12 works on 6.4.11

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Displayport to HDMI 2.1 adapters no longer working correctly on 6.4.12 works on 6.4.11

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