Bug 106974

Summary:	[CI] igt@* - warn - Suspicious CRC: it looks like the CRC read back was from a register in a powered down well
Product:	DRI	Reporter:	Martin Peres <martin.peres>
Component:	DRM/Intel	Assignee:	Intel GFX Bugs mailing list <intel-gfx-bugs>
Status:	CLOSED WORKSFORME	QA Contact:	Intel GFX Bugs mailing list <intel-gfx-bugs>
Severity:	normal
Priority:	medium	CC:	intel-gfx-bugs, jose.souza
Version:	XOrg git
Hardware:	Other
OS:	All
Whiteboard:
i915 platform:	GLK	i915 features:	display/PSR

Description Martin Peres 2018-06-20 08:35:38 UTC

https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_4345/shard-glk3/igt@kms_draw_crc@draw-method-rgb565-blt-xtiled.html

(kms_draw_crc:1272) igt_debugfs-WARNING: Warning on condition crc->crc[i] == 0xffffffff in function crc_sanity_checks, file ../lib/igt_debugfs.c:836
(kms_draw_crc:1272) igt_debugfs-WARNING: Suspicious CRC: it looks like the CRC read back was from a register in a powered down well
(kms_draw_crc:1272) igt_debugfs-WARNING: Warning on condition crc->crc[i] == 0xffffffff in function crc_sanity_checks, file ../lib/igt_debugfs.c:836
(kms_draw_crc:1272) igt_debugfs-WARNING: Suspicious CRC: it looks like the CRC read back was from a register in a powered down well

Comment 1 Ville Syrjala 2018-12-13 10:49:34 UTC

I was just looking at crcs on icl and spotted the following:
0x00098785 0xd2d6ad2b 0x00000000 0x00000000 0x00000000 0x00000000
0x00098786 0xd2d6ad2b 0x00000000 0x00000000 0x00000000 0x00000000
0x0009879b 0xffffffff 0x00000000 0x00000000 0x00000000 0x00000000
0x0009879c 0xd2d6ad2b 0x00000000 0x00000000 0x00000000 0x00000000
0x0009879d 0x82618fd1 0x00000000 0x00000000 0x00000000 0x00000000

So the frame counter jumps by quite a lot there and we get a bogus crc at the same time. As I immediately suspected the culprit is PSR. We should probably disable PSR while CRC capturing is enabled.

Comment 2 Lakshmi 2019-02-14 09:30:35 UTC

This issue occurred only once CI_DRM_4345_full (7 months, 4 weeks / 4433 runs ago). Closing this bug.

Comment 3 CI Bug Log 2019-02-14 16:20:13 UTC

The CI Bug Log issue associated to this bug has been archived.

New failures matching the above filters will not be associated to this bug anymore.

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