Bug 110780

Summary:	RX 580 and 5K displays, bandwidth validation failed with multiple monitors
Product:	DRI	Reporter:	Gaël HERMET <linuzel>
Component:	DRM/AMDgpu	Assignee:	Default DRI bug account <dri-devel>
Status:	RESOLVED MOVED	QA Contact:
Severity:	major
Priority:	medium	CC:	bugs, nicholas.kazlauskas, utenkov.vv87
Version:	unspecified
Hardware:	All
OS:	Linux (All)
Whiteboard:
i915 platform:		i915 features:

Description Gaël HERMET 2019-05-28 08:30:23 UTC

I have been facing an issue with my 5K display (iiyama ProLite XB2779QQS-S1).

It works fine as long as it is the only active monitor, as soon as I activate another monitor the main one (5k) can't display more than 4k.

Debug using "echo 0x4 > /sys/module/drm/parameters/debug" show this :
mai 23 09:01:22 bureau-gael /usr/lib/gdm3/gdm-x-session[3465]: (EE) AMDGPU(0): failed to set mode: Invalid argument
mai 23 09:01:22 bureau-gael kernel: [drm:dce112_validate_bandwidth [amdgpu]] dce112_validate_bandwidth: Bandwidth validation failed!

I disabled the check by forcing is_display_configuration_supported to return true in dce_calcs.c and it works fine.

I tried a lot of kernel (includig drm-tip and 5.2-rc1) and they all have the same issue.
My custom kernel with no validation is based on Ubuntu's 5.0.0-15-generic.

If I can help by providing more logs or test something ask and I will do my best.

Comment 1 Martin Peres 2019-11-19 09:29:29 UTC

-- GitLab Migration Automatic Message --

This bug has been migrated to freedesktop.org's GitLab instance and has been closed from further activity.

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