linux.git/drivers/gpu/drm/amd/display/dc/core, branch v5.6

drm/amd/display: Add link_rate quirk for Apple 15" MBP 2017

2020-03-13T13:20:32+00:00

This fixes a problem found on the MacBookPro 2017 Retina panel:

The panel reports 10 bpc color depth in its EDID, and the
firmware chooses link settings at boot which support enough
bandwidth for 10 bpc (324000 kbit/sec aka LINK_RATE_RBR2
aka 0xc), but the DP_MAX_LINK_RATE dpcd register only reports
2.7 Gbps (multiplier value 0xa) as possible, in direct
contradiction of what the firmware successfully set up.

This restricts the panel to 8 bpc, not providing the full
color depth of the panel on Linux <= 5.5. Additionally, commit
'4a8ca46bae8a ("drm/amd/display: Default max bpc to 16 for eDP")'
introduced into Linux 5.6-rc1 will unclamp panel depth to
its full 10 bpc, thereby requiring a eDP bandwidth for all
modes that exceeds the bandwidth available and causes all modes
to fail validation -> No modes for the laptop panel -> failure
to set any mode -> Panel goes dark.

This patch adds a quirk specific to the MBP 2017 15" Retina
panel to override reported max link rate to the correct maximum
of 0xc = LINK_RATE_RBR2 to fix the darkness and reduced display
precision.

Please apply for Linux 5.6+ to avoid regressing Apple MBP panel
support.

Signed-off-by: Mario Kleiner 
Signed-off-by: Alex Deucher

drm/amd/display: fix for-loop with incorrectly sized loop counter (v2)

2020-01-27T21:46:45+00:00

A for-loop is iterating from 0 up to 1000 however the loop variable count
is a u8 and hence not large enough.  Fix this by making count an int.
Also remove the redundant initialization of count since this is never used
and add { } on the loop statement make the loop block clearer.

v2: drop useless else (Walter Harms)

Addresses-Coverity: ("Operands don't affect result")
Fixes: ed581a0ace44 ("drm/amd/display: wait for update when setting dpg test pattern")
Signed-off-by: Colin Ian King 
Signed-off-by: Alex Deucher

drm/amd/display: do not allocate display_mode_lib unnecessarily

2020-01-27T21:46:45+00:00

This allocation isn't required and can fail when resuming from suspend.

Bug: https://gitlab.freedesktop.org/drm/amd/issues/1009
Signed-off-by: Dor Askayo 
Reviewed-by: Leo Li 
Signed-off-by: Alex Deucher

Revert "drm/amd/display: Don't skip link training for empty dongle"

2020-01-27T21:46:45+00:00

This reverts commit 80adaebd2d411b7d6872a097634848a71eb13d20.

[WHY]
This change was working around a regression that occured in this:
commit 0301ccbaf67d ("drm/amd/display: DP Compliance 400.1.1 failure")

With the fix to run verify_link_cap when the SINK_COUNT of
dongles becomes non-zero this change is no longer needed.

Cc: Louis Li 
Cc: Wenjing Liu 
Cc: Hersen Wu 
Cc: Eric Yang 
Reviewed-by: Wenjing Liu 
Signed-off-by: Harry Wentland 
Signed-off-by: Alex Deucher

drm/amd/display: Retrain dongles when SINK_COUNT becomes non-zero

2020-01-27T21:46:45+00:00

[WHY]
Two years ago the patch referenced by the Fixes tag stopped running
dp_verify_link_cap_with_retries during DP detection when the reason
for the detection was a short-pulse interrupt. This effectively meant
that we were no longer doing the verify_link_cap training on active
dongles when their SINK_COUNT changed from 0 to 1.

A year ago this was partly remedied with:
commit 80adaebd2d41 ("drm/amd/display: Don't skip link training for empty dongle")

This made sure that we trained the dongle on initial hotplug (without
connected downstream devices).

This is all fine and dandy if it weren't for the fact that there are
some dongles on the market that don't like link training when SINK_COUNT
is 0 These dongles will in fact indicate a SINK_COUNT of 0 immediately
after hotplug, even when a downstream device is connected, and then
trigger a shortpulse interrupt indicating a SINK_COUNT change to 1.

In order to play nicely we will need our policy to not link train an
active DP dongle when SINK_COUNT is 0 but ensure we train it when the
SINK_COUNT changes to 1.

[HOW]
Call dp_verify_link_cap_with_retries on detection even when the detection
is triggered from a short pulse interrupt.

With this change we can also revert this commit which we'll do in a separate
follow-up change:
commit 80adaebd2d41 ("drm/amd/display: Don't skip link training for empty dongle")

Fixes: 0301ccbaf67d ("drm/amd/display: DP Compliance 400.1.1 failure")
Suggested-by: Louis Li 
Tested-by: Louis Li 
Cc: Wenjing Liu 
Cc: Hersen Wu 
Cc: Eric Yang 
Reviewed-by: Wenjing Liu 
Signed-off-by: Harry Wentland 
Signed-off-by: Alex Deucher

drm/amd/display: support VSC SDP update on video test pattern request

2020-01-22T21:55:28+00:00

[why]
MSA will be deprecated in the future.
Need to support VSC during DP test automation.

[how]
Do not disable VSC during DP test automation.
TODO - need to add VSC update on DM side on test request.

Signed-off-by: Wenjing Liu 
Reviewed-by: Nikola Cornij 
Acked-by: Bhawanpreet Lakha 
Signed-off-by: Alex Deucher

drm/amd/display: check pipe_ctx is split pipe or not

2020-01-22T21:55:27+00:00

[Why]
Driver use pipe_ctx to reallocate payload may cause allocate
payload twice on same sink with split pipe.

[How]
Drvier must to check pipe_ctx is split pipe or not to avoid
reallocate payload twice on same sink.

Signed-off-by: Paul Hsieh 
Reviewed-by: Tony Cheng 
Acked-by: Bhawanpreet Lakha 
Signed-off-by: Alex Deucher

drm/amd/display: Do not send training pattern if VS Different

2020-01-22T21:55:27+00:00

[Why]
The DP 1.4a Spec requires that training pattern only under certain
specific conditions. Currently driver will re-send
training pattern every time voltage swing value changes,
but that should not be the case.

[How]
Do not re-send training pattern every time VS values
are different. Only send it on the first iteration.

Signed-off-by: Sung Lee 
Reviewed-by: Tony Cheng 
Acked-by: Abdoulaye Berthe 
Acked-by: Bhawanpreet Lakha 
Signed-off-by: Alex Deucher

drm/amd/display: update MSA and VSC SDP on video test pattern request

2020-01-22T21:55:27+00:00

[why]
On video test pattern request we need to update MSA and VSC so
it will match the requested test pattern dynamic range field.

[how]
Update dynamic range field in MSA and disable VSC as updating VSC
info packet is complicated and not required for test pattern purpose.

Signed-off-by: Wenjing Liu 
Reviewed-by: Nikola Cornij 
Acked-by: Bhawanpreet Lakha 
Signed-off-by: Alex Deucher

drm/amd/display: reallocate MST payload when link loss

2020-01-16T19:16:54+00:00

[Why]
Try to allocate MST payload but receive HPD short pulse with link loss
casue driver allocate payload twice. It cause monitor can't light up
successfully.

[How]
When driver receive HPD short pulse with link loss, we need to
deallocate payload then allocate payload.
Then we will not allocate payload twice with same sink.

Signed-off-by: Paul Hsieh 
Reviewed-by: Tony Cheng 
Acked-by: Harry Wentland 
Acked-by: Rodrigo Siqueira 
Signed-off-by: Alex Deucher