linux.git/drivers/gpu/drm/amd/display/dc/link, branch v6.15 Linux kernel source tree drm/amd/display: fix link_set_dpms_off multi-display MST corner case 2025-05-13T18:22:03+00:00 George Shen george.shen@amd.com 2025-04-24T14:02:59+00:00 3c1a467372e0c356b1d3c59f6d199ed5a6612dd1 [Why & How] When MST config is unplugged/replugged too quickly, it can potentially result in a scenario where previous DC state has not been reset before the HPD link detection sequence begins. In this case, driver will disable the streams/link prior to re-enabling the link for link training. There is a bug in the current logic that does not account for the fact that current_state can be released and cleared prior to swapping to a new state (resulting in the pipe_ctx stream pointers to be cleared) in between disabling streams. To resolve this, cache the original streams prior to committing any stream updates. Reviewed-by: Wenjing Liu <wenjing.liu@amd.com> Signed-off-by: George Shen <george.shen@amd.com> Signed-off-by: Ray Wu <ray.wu@amd.com> Tested-by: Daniel Wheeler <daniel.wheeler@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> (cherry picked from commit 1561782686ccc36af844d55d31b44c938dd412dc) 
[Why & How]
When MST config is unplugged/replugged too quickly, it can potentially
result in a scenario where previous DC state has not been reset before
the HPD link detection sequence begins. In this case, driver will
disable the streams/link prior to re-enabling the link for link
training.

There is a bug in the current logic that does not account for the fact
that current_state can be released and cleared prior to swapping to a
new state (resulting in the pipe_ctx stream pointers to be cleared) in
between disabling streams.

To resolve this, cache the original streams prior to committing any
stream updates.

Reviewed-by: Wenjing Liu <wenjing.liu@amd.com>
Signed-off-by: George Shen <george.shen@amd.com>
Signed-off-by: Ray Wu <ray.wu@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit 1561782686ccc36af844d55d31b44c938dd412dc)
drm/amd/display: Use 16ms AUX read interval for LTTPR with old sinks 2025-04-22T20:49:15+00:00 George Shen george.shen@amd.com 2025-04-07T16:35:57+00:00 d59bddce49bfd323f1218bb6c3ad314e5c4e8f9d [Why/How] LTTPR are required to program DPCD 0000Eh to 0x4 (16ms) upon AUX read reply to this register. Since old Sinks witih DPCD rev 1.1 and earlier may not support this register, assume the mandatory value is programmed by the LTTPR to avoid AUX timeout issues. Reviewed-by: Wenjing Liu <wenjing.liu@amd.com> Signed-off-by: George Shen <george.shen@amd.com> Signed-off-by: Zaeem Mohamed <zaeem.mohamed@amd.com> Tested-by: Mark Broadworth <mark.broadworth@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> (cherry picked from commit 1594b60d74959c0680ddf777a74963c98afcdd7e) 
[Why/How]
LTTPR are required to program DPCD 0000Eh to 0x4 (16ms) upon AUX read
reply to this register. Since old Sinks witih DPCD rev 1.1 and earlier
may not support this register, assume the mandatory value is programmed
by the LTTPR to avoid AUX timeout issues.

Reviewed-by: Wenjing Liu <wenjing.liu@amd.com>
Signed-off-by: George Shen <george.shen@amd.com>
Signed-off-by: Zaeem Mohamed <zaeem.mohamed@amd.com>
Tested-by: Mark Broadworth <mark.broadworth@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit 1594b60d74959c0680ddf777a74963c98afcdd7e)
drm/amd/display: Revert "Support for reg inbox0 for host->DMUB CMDs" 2025-03-18T18:03:46+00:00 Dillon Varone dillon.varone@amd.com 2025-03-03T21:48:50+00:00 b3d58262dca62525783d1ab6688e22103c2db010 This reverts commit 15d1c2e6bf60511ba068d7d735d051911c6c5b92. Reason: Cursor movement causes system to hang. Reviewed-by: Aric Cyr <aric.cyr@amd.com> Signed-off-by: Dillon Varone <dillon.varone@amd.com> Signed-off-by: Alex Hung <alex.hung@amd.com> Tested-by: Daniel Wheeler <daniel.wheeler@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> 
This reverts commit 15d1c2e6bf60511ba068d7d735d051911c6c5b92.

Reason: Cursor movement causes system to hang.

Reviewed-by: Aric Cyr <aric.cyr@amd.com>
Signed-off-by: Dillon Varone <dillon.varone@amd.com>
Signed-off-by: Alex Hung <alex.hung@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
drm/amd/display: Change notification of link BW allocation 2025-03-18T18:03:46+00:00 Cruise Hung Cruise.Hung@amd.com 2025-02-25T15:03:29+00:00 52af17eabb1049743869edf861053b96aea22e04 [WHY & HOW] The response of DP BW allocation is handled in Outbox ISR. When it failed to request the DP BW allocation, it sent another DPCD request in Outbox ISR immediately. The DP AUX reply also uses the Outbox ISR. So, no AUX reply happened in this case. Change to use HPD IRQ for the notification. Reviewed-by: Meenakshikumar Somasundaram <meenakshikumar.somasundaram@amd.com> Signed-off-by: Cruise Hung <Cruise.Hung@amd.com> Signed-off-by: Alex Hung <alex.hung@amd.com> Tested-by: Daniel Wheeler <daniel.wheeler@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> 
[WHY & HOW]
The response of DP BW allocation is handled in Outbox ISR.
When it failed to request the DP BW allocation, it sent another
DPCD request in Outbox ISR immediately. The DP AUX reply also
uses the Outbox ISR. So, no AUX reply happened in this case.
Change to use HPD IRQ for the notification.

Reviewed-by: Meenakshikumar Somasundaram <meenakshikumar.somasundaram@amd.com>
Signed-off-by: Cruise Hung <Cruise.Hung@amd.com>
Signed-off-by: Alex Hung <alex.hung@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
drm/amd/display: Add Support for reg inbox0 for host->DMUB CMDs 2025-03-10T17:28:47+00:00 Dillon Varone dillon.varone@amd.com 2024-12-20T22:01:29+00:00 15d1c2e6bf60511ba068d7d735d051911c6c5b92 [WHY] DCN4+ supports a new register based mailbox for sending messages from host to DMCUB. This mailbox supports 64 byte commands, which makes it compatible with the same structure as the frame buffer based mailbox. [HOW] The intention for reg_inbox0 is to be slot in replacement for the frame buffer based mailbox (Inbox1). It supports all of the required features: - Supports all messages handled by FB Inbox1 - Supports multi command batching Reviewed-by: Joshua Aberback <joshua.aberback@amd.com> Signed-off-by: Dillon Varone <dillon.varone@amd.com> Signed-off-by: Tom Chung <chiahsuan.chung@amd.com> Tested-by: Daniel Wheeler <daniel.wheeler@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> 
[WHY]
DCN4+ supports a new register based mailbox for sending messages
from host to DMCUB. This mailbox supports 64 byte commands, which makes
it compatible with the same structure as the frame buffer based mailbox.

[HOW]
The intention for reg_inbox0 is to be slot in replacement for the frame
buffer based mailbox (Inbox1). It supports all of the required features:
- Supports all messages handled by FB Inbox1
- Supports multi command batching

Reviewed-by: Joshua Aberback <joshua.aberback@amd.com>
Signed-off-by: Dillon Varone <dillon.varone@amd.com>
Signed-off-by: Tom Chung <chiahsuan.chung@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
drm/amd/display: Implement PCON regulated autonomous mode handling 2025-03-10T17:28:34+00:00 George Shen george.shen@amd.com 2025-02-13T19:46:49+00:00 084e0735448ae4d01928b537c03c7042aef2ab81 [Why/How] DP spec has been updated recently to make regulated autonomous mode more well-defined. In case any PCON vendors choose to implement regulated autonomous mode in the future, pre-emptively add handling for the regulated autonomous mode based on current spec. Reviewed-by: Wenjing Liu <wenjing.liu@amd.com> Signed-off-by: George Shen <george.shen@amd.com> Signed-off-by: Tom Chung <chiahsuan.chung@amd.com> Tested-by: Daniel Wheeler <daniel.wheeler@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> 
[Why/How]
DP spec has been updated recently to make regulated autonomous mode more
well-defined. In case any PCON vendors choose to implement regulated
autonomous mode in the future, pre-emptively add handling for the
regulated autonomous mode based on current spec.

Reviewed-by: Wenjing Liu <wenjing.liu@amd.com>
Signed-off-by: George Shen <george.shen@amd.com>
Signed-off-by: Tom Chung <chiahsuan.chung@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
drm/amd/display: not abort link train when bw is low 2025-03-10T17:28:27+00:00 Peichen Huang PeiChen.Huang@amd.com 2025-02-25T06:52:30+00:00 8a21da2842bb22b2b80e5902d0438030d729bfd3 [WHY] DP tunneling should not abort link train even bandwidth become too low after downgrade. Otherwise, it would fail compliance test. [HOW} Do link train with downgrade settings even bandwidth is not enough Reviewed-by: Cruise Hung <cruise.hung@amd.com> Reviewed-by: Meenakshikumar Somasundaram <meenakshikumar.somasundaram@amd.com> Signed-off-by: Peichen Huang <PeiChen.Huang@amd.com> Signed-off-by: Tom Chung <chiahsuan.chung@amd.com> Tested-by: Daniel Wheeler <daniel.wheeler@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> 
[WHY]
DP tunneling should not abort link train even bandwidth become
too low after downgrade. Otherwise, it would fail compliance test.

[HOW}
Do link train with downgrade settings even bandwidth is not enough

Reviewed-by: Cruise Hung <cruise.hung@amd.com>
Reviewed-by: Meenakshikumar Somasundaram <meenakshikumar.somasundaram@amd.com>
Signed-off-by: Peichen Huang <PeiChen.Huang@amd.com>
Signed-off-by: Tom Chung <chiahsuan.chung@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
drm/amd/display: Fix incorrect DPCD configs while Replay/PSR switch 2025-03-10T17:23:25+00:00 Leon Huang Leon.Huang1@amd.com 2025-02-11T07:45:43+00:00 0d9cabc8f591ea1cd97c071b853b75b155c13259 [Why] When switching between PSR/Replay, the DPCD config of previous mode is not cleared, resulting in unexpected behavior in TCON. [How] Initialize the DPCD in setup function Reviewed-by: Robin Chen <robin.chen@amd.com> Signed-off-by: Leon Huang <Leon.Huang1@amd.com> Signed-off-by: Tom Chung <chiahsuan.chung@amd.com> Tested-by: Daniel Wheeler <daniel.wheeler@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> 
[Why]
When switching between PSR/Replay,
the DPCD config of previous mode is not cleared,
resulting in unexpected behavior in TCON.

[How]
Initialize the DPCD in setup function

Reviewed-by: Robin Chen <robin.chen@amd.com>
Signed-off-by: Leon Huang <Leon.Huang1@amd.com>
Signed-off-by: Tom Chung <chiahsuan.chung@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
drm/amd/display: Add tunneling IRQ handler 2025-03-05T15:41:08+00:00 Cruise Hung Cruise.Hung@amd.com 2025-02-20T03:29:50+00:00 c286e8501adedc2a22620a5c60dcd14286b38514 USB4 DP BW Allocation uses DP_TUNNELING_IRQ to indicate the status update. The DP_TUNNELING_IRQ is defined in LINK_SERVICE_IRQ_VECTOR_ESI0. When receiving DP HPD IRQ in USB4, read the LINK_SERVICE_IRQ_VECTOR_ESI0. Reviewed-by: Wenjing Liu <wenjing.liu@amd.com> Signed-off-by: Cruise Hung <Cruise.Hung@amd.com> Signed-off-by: Wayne Lin <wayne.lin@amd.com> Tested-by: Daniel Wheeler <daniel.wheeler@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> 
USB4 DP BW Allocation uses DP_TUNNELING_IRQ to indicate the status update.
The DP_TUNNELING_IRQ is defined in LINK_SERVICE_IRQ_VECTOR_ESI0. When
receiving DP HPD IRQ in USB4, read the LINK_SERVICE_IRQ_VECTOR_ESI0.

Reviewed-by: Wenjing Liu <wenjing.liu@amd.com>
Signed-off-by: Cruise Hung <Cruise.Hung@amd.com>
Signed-off-by: Wayne Lin <wayne.lin@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
drm/amd/display: Skip checking FRL_MODE bit for PCON BW determination 2025-03-05T15:39:28+00:00 George Shen george.shen@amd.com 2025-02-15T03:00:13+00:00 0584bbcf0c53c133081100e4f4c9fe41e598d045 [Why/How] Certain PCON will clear the FRL_MODE bit despite supporting the link BW indicated in the other bits. Thus, skip checking the FRL_MODE bit when interpreting the hdmi_encoded_link_bw struct. Reviewed-by: Wenjing Liu <wenjing.liu@amd.com> Signed-off-by: George Shen <george.shen@amd.com> Signed-off-by: Wayne Lin <wayne.lin@amd.com> Tested-by: Daniel Wheeler <daniel.wheeler@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> 
[Why/How]
Certain PCON will clear the FRL_MODE bit despite supporting the link BW
indicated in the other bits.

Thus, skip checking the FRL_MODE bit when interpreting the
hdmi_encoded_link_bw struct.

Reviewed-by: Wenjing Liu <wenjing.liu@amd.com>
Signed-off-by: George Shen <george.shen@amd.com>
Signed-off-by: Wayne Lin <wayne.lin@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>