[Bug 107978] [amdgpu] Switching to tty fails with DisplayPort monitor going to sleep (REG_WAIT timeout / dce110_stream_encoder_dp_blank)

[b***@freedesktop.org]

https://bugs.freedesktop.org/show_bug.cgi?id=107978

Bug ID: 107978
Summary: [amdgpu] Switching to tty fails with DisplayPort
monitor going to sleep (REG_WAIT timeout /
dce110_stream_encoder_dp_blank)
Product: DRI
Version: unspecified
Hardware: x86-64 (AMD64)
OS: Linux (All)
Status: NEW
Severity: normal
Priority: medium
Component: DRM/AMDgpu
Assignee: dri-***@lists.freedesktop.org
Reporter: ***@gmail.com

After upgrading to Linux 4.19-rc3 (from 4.18.x), I can't switch to tty anymore,
the monitor connected over DisplayPort goes into sleep mode.

I see this in dmesg when it happens:

[37342.777399] [drm:generic_reg_wait [amdgpu]] *ERROR* REG_WAIT timeout 10us *
3000 tries - dce110_stream_encoder_dp_blank line:922
[37342.777477] WARNING: CPU: 4 PID: 14403 at
drivers/gpu/drm/amd/amdgpu/../display/dc/dc_helper.c:254
generic_reg_wait+0xe7/0x160 [amdgpu]
[37342.777478] Modules linked in: uas usb_storage rfcomm ebtable_filter
ebtables devlink ip6table_filter ip6_tables iptable_filter cmac bnep arc4
nls_ascii nls_cp437 vfat amdkfd fat snd_hda_codec_realtek snd_hda_codec_generic
edac_mce_amd btusb btrtl amdgpu btbcm snd_hda_codec_hdmi btintel iwlmvm
snd_usb_audio snd_hda_intel bluetooth kvm_amd snd_hda_codec snd_usbmidi_lib
wmi_bmof mxm_wmi mac80211 snd_hda_core kvm uvcvideo videobuf2_vmalloc snd_hwdep
videobuf2_memops snd_rawmidi jitterentropy_rng videobuf2_v4l2 videobuf2_common
snd_seq_device chash iwlwifi irqbypass gpu_sched videodev snd_pcm
crct10dif_pclmul ttm crc32_pclmul media drbg snd_timer evdev drm_kms_helper
cfg80211 ansi_cprng ghash_clmulni_intel efi_pstore pcspkr drm snd k10temp
ecdh_generic soundcore efivars rfkill crc16 sp5100_tco sg ccp
[37342.777514] rng_core wmi pcc_cpufreq button acpi_cpufreq nct6775 hwmon_vid
parport_pc ppdev lp parport efivarfs ip_tables x_tables autofs4 xfs btrfs xor
zstd_decompress zstd_compress xxhash raid6_pq libcrc32c crc32c_generic
hid_generic usbhid hid sd_mod crc32c_intel ahci xhci_pci libahci aesni_intel
xhci_hcd aes_x86_64 crypto_simd libata igb cryptd glue_helper nvme usbcore
scsi_mod i2c_piix4 i2c_algo_bit nvme_core dca usb_common gpio_amdpt
gpio_generic
[37342.777542] CPU: 4 PID: 14403 Comm: kworker/4:1 Tainted: G W
4.19.0-rc3-amd64 #1 Debian 4.19~rc3-1~exp1
[37342.777542] Hardware name: To Be Filled By O.E.M. To Be Filled By
O.E.M./X370 Taichi, BIOS L4.64 04/03/2018
[37342.777558] Workqueue: events drm_mode_rmfb_work_fn [drm]
[37342.777615] RIP: 0010:generic_reg_wait+0xe7/0x160 [amdgpu]
[37342.777617] Code: 44 24 58 8b 54 24 48 89 de 44 89 4c 24 08 48 8b 4c 24 50
48 c7 c7 20 9d b5 c1 e8 64 e6 f0 fe 83 7d 18 01 44 8b 4c 24 08 74 02 <0f> 0b 48
83 c4 10 44 89 c8 5b 5d 41 5c 41 5d 41 5e 41 5f c3 41 0f
[37342.777618] RSP: 0018:ffffa2ae81b9ba20 EFLAGS: 00010297
[37342.777620] RAX: 0000000000000000 RBX: 000000000000000a RCX:
0000000000000000
[37342.777621] RDX: 0000000000000000 RSI: ffff93d74eb166a8 RDI:
ffff93d74eb166a8
[37342.777622] RBP: ffff93d746439180 R08: 0000000000000000 R09:
0000000000010200
[37342.777623] R10: 0720072007200720 R11: 0720073207320739 R12:
0000000000000bb9
[37342.777624] R13: 00000000000051e2 R14: 0000000000010000 R15:
0000000000000000
[37342.777625] FS: 0000000000000000(0000) GS:ffff93d74eb00000(0000)
knlGS:0000000000000000
[37342.777626] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[37342.777627] CR2: 0000558f62bfa9d0 CR3: 00000003f2c38000 CR4:
00000000003406e0
[37342.777628] Call Trace:
[37342.777695] dce110_stream_encoder_dp_blank+0x12c/0x1a0 [amdgpu]
[37342.777754] core_link_disable_stream+0x54/0x220 [amdgpu]
[37342.777813] dce110_reset_hw_ctx_wrap+0xc1/0x1e0 [amdgpu]
[37342.777872] dce110_apply_ctx_to_hw+0x45/0x650 [amdgpu]
[37342.777928] ? dc_remove_plane_from_context+0x1fc/0x240 [amdgpu]
[37342.777985] dc_commit_state+0x2c6/0x520 [amdgpu]
[37342.778047] amdgpu_dm_atomic_commit_tail+0x37a/0xd80 [amdgpu]
[37342.778052] ? __wake_up_common_lock+0x89/0xc0
[37342.778054] ? _cond_resched+0x15/0x30
[37342.778056] ? wait_for_completion_timeout+0x3b/0x1a0
[37342.778117] ? amdgpu_dm_atomic_commit_tail+0xd80/0xd80 [amdgpu]
[37342.778126] commit_tail+0x3d/0x70 [drm_kms_helper]
[37342.778133] drm_atomic_helper_commit+0xb4/0x120 [drm_kms_helper]
[37342.778148] drm_framebuffer_remove+0x361/0x410 [drm]
[37342.778164] drm_mode_rmfb_work_fn+0x4f/0x60 [drm]
[37342.778167] process_one_work+0x1a7/0x360
[37342.778169] worker_thread+0x30/0x390
[37342.778171] ? pwq_unbound_release_workfn+0xd0/0xd0
[37342.778173] kthread+0x112/0x130
[37342.778175] ? kthread_bind+0x30/0x30
[37342.778177] ret_from_fork+0x22/0x40
[37342.778179] ---[ end trace 3d987dd66a59ffb4 ]---

OS: Debian testing, kernel 4.19~rc3-1~exp1
GPU: Sapphire Pulse Vega 56.
amdgpu firmware: 20180825+dfsg-1

[b***@freedesktop.org]

https://bugs.freedesktop.org/show_bug.cgi?id=107978

--- Comment #1 from Shmerl <***@gmail.com> ---
Same thing happens with kernel 4.19-rc4.

[b***@freedesktop.org]

https://bugs.freedesktop.org/show_bug.cgi?id=107978

--- Comment #2 from Shmerl <***@gmail.com> ---
Still broken with 4.19.0-rc6-amd64.

[b***@freedesktop.org]

https://bugs.freedesktop.org/show_bug.cgi?id=107978

--- Comment #3 from Shmerl <***@gmail.com> ---
Is this issue Debian specific or anyone observed it in other distros? Because
if it's something wrong with Debian's kernel build I should probably file a
Debian bug about it.

[b***@freedesktop.org]

https://bugs.freedesktop.org/show_bug.cgi?id=107978

--- Comment #4 from george <***@rylos.net> ---
I have same problem on Fedora F28 with 4.18 kernel. I have since switched back
to DVI interface which does not exhibit this bug.

[b***@freedesktop.org]

https://bugs.freedesktop.org/show_bug.cgi?id=107978

--- Comment #5 from Shmerl <***@gmail.com> ---
My card doesn't have DVI, and HDMI produces horrible colors, so DisplayPort is
the only sane option and it's broken :(

[b***@freedesktop.org]

https://bugs.freedesktop.org/show_bug.cgi?id=107978

Nicholas Kazlauskas <***@amd.com> changed:

What |Removed |Added
----------------------------------------------------------------------------
CC| |***@amd.com

--- Comment #6 from Nicholas Kazlauskas <***@amd.com> ---
I haven't observed this behavior occurring under Ubuntu 18.04 or Arch on 4.18
or 4.19 kernels with a Vega 56.

Do you mind posting a full dmesg log with drm.debug=4 and an xorg log? It would
also help to know what desktop environment you're using.

[b***@freedesktop.org]

https://bugs.freedesktop.org/show_bug.cgi?id=107978

--- Comment #7 from Shmerl <***@gmail.com> ---
I'm using KDE Plasma 5.13.5, current Debian testing x86_64. Can you try it with
Debian? Ubuntu stack is not that close anymore.

I also noticed one detail. When screen mode is chaning (like before sddm comes
up), the monitor goes to sleep briefly and then wakes up. That wasn't happening
before and it's not a correct behavior. In 4.18 it wasn't waking up at all, and
it was fixed in 4.19. Similar thing is happening during switch to tty (screen
mode is changing indicated by the DP monitor icon appearing), except the
monitor isn't waking up anymore.

[b***@freedesktop.org]

https://bugs.freedesktop.org/show_bug.cgi?id=107978

--- Comment #8 from Shmerl <***@gmail.com> ---
Created attachment 141960
--> https://bugs.freedesktop.org/attachment.cgi?id=141960&action=edit
dmesg with drm.debug=4 and Xorg.0.log

Attaching logs.

[b***@freedesktop.org]

https://bugs.freedesktop.org/show_bug.cgi?id=107978

--- Comment #9 from Shmerl <***@gmail.com> ---
By the way, I tested it with this kernel:

https://github.com/M-Bab/linux-kernel-amdgpu-binaries/blob/master/linux-image-4.19.0-rc6_18.09.30.amdgpu_amd64.deb

Which is built from AMD's tree. This issue is also present in it.

[b***@freedesktop.org]

https://bugs.freedesktop.org/show_bug.cgi?id=107978

--- Comment #10 from Shmerl <***@gmail.com> ---
I just found something. My monitor - Dell U2413 has a setting for toggling
DisplayPort 1.2. It was enabled until now. When I disable that setting, tty
starts working!

My cable is supposed to support DP 1.2 and be Vesa compliant. It's Accel
UltraAV DP 1.2 cable.

I hope this can help narrow down the problem.

[b***@freedesktop.org]

https://bugs.freedesktop.org/show_bug.cgi?id=107978

Shmerl <***@gmail.com> changed:

What |Removed |Added
----------------------------------------------------------------------------
Summary|[amdgpu] Switching to tty |[amdgpu] Switching to tty
|fails with DisplayPort |fails with DisplayPort 1.2
|monitor going to sleep |monitor going to sleep
|(REG_WAIT timeout / |(REG_WAIT timeout /
|dce110_stream_encoder_dp_bl |dce110_stream_encoder_dp_bl
|ank) |ank)

[b***@freedesktop.org]

https://bugs.freedesktop.org/show_bug.cgi?id=107978

--- Comment #11 from george <***@rylos.net> ---
(In reply to Shmerl from comment #10)

Post by b***@freedesktop.org
I just found something. My monitor - Dell U2413 has a setting for toggling
DisplayPort 1.2. It was enabled until now. When I disable that setting, tty
starts working!
My cable is supposed to support DP 1.2 and be Vesa compliant. It's Accel
UltraAV DP 1.2 cable.
I hope this can help narrow down the problem.

Interesting, I have the exact same monitor, Dell U2413, I'll give this a try!

[b***@freedesktop.org]

https://bugs.freedesktop.org/show_bug.cgi?id=107978

--- Comment #12 from Shmerl <***@gmail.com> ---
@Nicholas Kazlauskas: does it help to identify the source of the problem?

[b***@freedesktop.org]

https://bugs.freedesktop.org/show_bug.cgi?id=107978

--- Comment #13 from Nicholas Kazlauskas <***@amd.com> ---
(In reply to Shmerl from comment #12)

Post by b***@freedesktop.org
@Nicholas Kazlauskas: does it help to identify the source of the problem?

If I had to guess I would say this is an issue specific to that monitor - DP
1.2 should generally work without issue.

This does help narrow down the problem, thanks.

[b***@freedesktop.org]

https://bugs.freedesktop.org/show_bug.cgi?id=107978

--- Comment #14 from Shmerl <***@gmail.com> ---
(In reply to Nicholas Kazlauskas from comment #13)

Post by b***@freedesktop.org
If I had to guess I would say this is an issue specific to that monitor - DP
1.2 should generally work without issue.

It did work fine before in DP 1.2 mode (like with kernel 4.17.x), so there must
have been some regression which caused this behavior.

[b***@freedesktop.org]

https://bugs.freedesktop.org/show_bug.cgi?id=107978

--- Comment #15 from ***@sibrenvasse.nl ---
I own a DELL U2414H and a U2913WM, and are daisy chained via DisplayPort. I'm
currently running into this issue.

A quick bisect gave this result:
# first bad commit: [0d99889109892396a8164bf6dd178e36d3fe3166] drm/fb-helper:
Eliminate the .best_encoder() usage

[b***@freedesktop.org]

https://bugs.freedesktop.org/show_bug.cgi?id=107978

--- Comment #16 from Daniel Exner <dex+***@dragonslave.de> ---
I own a Dell U3415W also connected via DisplayPort and I have the same issue.

Worked like a charm in the past.

[b***@freedesktop.org]

https://bugs.freedesktop.org/show_bug.cgi?id=107978

--- Comment #17 from Shmerl <***@gmail.com> ---
(In reply to Nicholas Kazlauskas from comment #13)

Post by b***@freedesktop.org
This does help narrow down the problem, thanks.

Is there any chance of fixing this in 4.20?

[b***@freedesktop.org]

https://bugs.freedesktop.org/show_bug.cgi?id=107978

--- Comment #18 from Robin <account-***@tripp.xyz> ---
Same problem for me.
Using 2 identical DELL U2415 and a Radeon RX 580.
On Arch with 4.18.x Daisychainig both monitors worked like a charm.
After upgrading to 4.19 the monitors only work when I`m disableing DP1.2. But
then I obviously can't Daisychain.
Is there any way I can help troubleshoot this?

[b***@freedesktop.org]

https://bugs.freedesktop.org/show_bug.cgi?id=107978

--- Comment #19 from Shmerl <***@gmail.com> ---
This seem to commonly affect Dell monitors. Do they not follow DisplayPort 1.2
spec, or amdgpu is doing something incorrectly after all?

[b***@freedesktop.org]

https://bugs.freedesktop.org/show_bug.cgi?id=107978

--- Comment #20 from Jerry Zuo <***@amd.com> ---
The fix is showing up since 4.20-rc5. Please give a try.

[b***@freedesktop.org]

https://bugs.freedesktop.org/show_bug.cgi?id=107978

--- Comment #21 from Sibren Vasse <***@sibrenvasse.nl> ---
(In reply to Jerry Zuo from comment #20)

Post by b***@freedesktop.org
The fix is showing up since 4.20-rc5. Please give a try.

4.20-rc5 solves the problem for me!

[b***@freedesktop.org]

https://bugs.freedesktop.org/show_bug.cgi?id=107978

--- Comment #22 from Shmerl <***@gmail.com> ---
Great news! Debian didn't get 4.20 rc kernels yet, but I can try building one
from source to test.

[b***@freedesktop.org]

https://bugs.freedesktop.org/show_bug.cgi?id=107978

--- Comment #23 from Sibren Vasse <***@sibrenvasse.nl> ---
Switching to tty now works for me , I still get the [drm:generic_reg_wait
[amdgpu]] *ERROR* REG_WAIT timeout 10us * 3000 tries -
dce110_stream_encoder_dp_blank line:944 message though

[b***@freedesktop.org]

https://bugs.freedesktop.org/show_bug.cgi?id=107978

--- Comment #24 from Shmerl <***@gmail.com> ---
Does KWin Wayland session work for you now? It was crashing also because of
this.

[b***@freedesktop.org]

https://bugs.freedesktop.org/show_bug.cgi?id=107978

--- Comment #25 from Shmerl <***@gmail.com> ---
Just built 4.20-rc5+. This is indeed fixed, and KWin Wayland session is finally
working with DisplayPort 1.2 enabled!

[b***@freedesktop.org]

https://bugs.freedesktop.org/show_bug.cgi?id=107978

--- Comment #26 from Shmerl <***@gmail.com> ---
And I don't see ERROR* REG_WAIT anymore. I'm using latest Vega firmware.

[b***@freedesktop.org]

https://bugs.freedesktop.org/show_bug.cgi?id=107978

--- Comment #27 from Jerry Zuo <***@amd.com> ---
The dce110_stream_encoder_dp_blank timeout is something I am working on. It
doesn't break anything, but pretty annoying.