tree ca037a636563e3cfb8386ed254214e668d18bb97
parent 2ebfaf5f10c6f00d4232f741c82c421eca8ae784
author Paulo Zanoni <paulo.r.zanoni@intel.com> 1413582123 -0300
committer Daniel Vetter <daniel.vetter@ffwll.ch> 1414161250 +0200

drm/i915: disable IPS while getting the pipe CRCs.

For some yet-undiscovered reason, when IPS gets enabled, the pipe CRC
changes. Since hsw_enable_ips() doesn't really guarantees to enable
IPS (it depends on package C-states), we can't really predict if IPS
is enabled or disabled while running our CRC tests, so let's just
completely disable IPS while pipe CRCs are being used.

If we find a way to make IPS not change the pipe CRC result, we may
want to fix IPS and then revert this patch. While this doesn't happen,
let's merge this patch, so every IGT test relying on the CRCs can
work on pipe A.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=72864
Testcase: igt/kms_cursor_crc (and others)
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>