The CI Bug Log issue associated to this bug has been updated.

### New filters associated

* ICL: igt@kms_setmode@invalid-clone-single-crtc-stealing - fail - Failed assertion: ret == 0, Last errno: 22, Invalid argument

  - https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_5891/re-icl-u/igt@kms_setmode@invalid-clone-single-crtc-stealing.html

This test has been failing 100% of the time on re-icl-u, and only this one...

This might be explained by the fact that this is the only machine that has a chamelium connected to its mDP port.

The test is supposed to check that one CRTC stealing an already-used encoder is not accepted by atomic. However, in this particular case, the failure happens on the first modeset (the one where we want to try stealing the encoder from).

Here is the relevant failure:

<7> [23.795360] [drm:drm_mode_setcrtc] [CRTC:82:pipe A]
<7> [23.795445] [drm:drm_mode_setcrtc] [CONNECTOR:196:DP-1]
<7> [23.795602] [drm:intel_atomic_check [i915]] [CONNECTOR:196:DP-1] Limiting display bpp to 24 instead of EDID bpp 24, requested bpp 36, max platform bpp 36
<7> [23.795668] [drm:intel_dp_compute_config [i915]] DP link computation with max lane count 4 max rate 270000 max bpp 24 pixel clock 533250KHz
<7> [23.795731] [drm:intel_dp_compute_config [i915]] Force DSC en = 0
<7> [23.795788] [drm:intel_atomic_check [i915]] Encoder config failure: -22

The failure is likely caused by this function that gets mode to set on all connectors:

static void get_mode_for_crtc(struct crtc_config *crtc,
			      drmModeModeInfo *mode_ret)
{
	drmModeModeInfo mode;
	int i;

	/*
	 * First try to select a default mode that is supported by all
	 * connectors.
	 */
	for (i = 0; i < crtc->connector_count; i++) {
		mode = crtc->cconfs[i].default_mode;
		if (crtc_supports_mode(crtc, &mode))
			goto found;
	}

	/*
	 * Then just fall back to find any that is supported by all
	 * connectors.
	 */
	for (i = 0; i < crtc->cconfs[0].connector->count_modes; i++) {
		mode = crtc->cconfs[0].connector->modes[i];
		if (crtc_supports_mode(crtc, &mode))
			goto found;
	}

	/*
	 * If none is found then just pick the default mode of the first
	 * connector and hope the other connectors can support it by scaling
	 * etc.
	 */
	mode = crtc->cconfs[0].default_mode;
found:
	*mode_ret = mode;
}

eDP quite likely supports 36bpp but DP does not. Because of the wrong assumptions above we try to set this 36bpp mode on the DP connector, failing on the first drmModeSetCrtc().

The test should be fixed by being more clever about mode selection or just skipping if connector happens to not support given mode, instead of asserting straight away.

Dropping priority to medium, as this is a test issue.

This test is pretty generic, so if some machines fail/skip it, it is not lost test coverage. I think you are with the priority!

https://patchwork.freedesktop.org/patch/301948/?series=59930

commit 6cfbf0365f39d68fcaabcd0498ffec28d1528d8f (HEAD, origin/master, origin/HEAD)
Author: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Date:   Thu Apr 25 10:41:02 2019 +0200

    tests/kms_setmode: Handle eDP with fixed mode better.