Partially revert "drm/i915: unconditionally use mt forcewake on hsw/ivb"
Partially revert "drm/i915: unconditionally use mt forcewake on hsw/ivb"

commit c11e5f35ab490bd30591563816fbc83526521777 upstream.

This patch partially reverts commit 36ec8f877481449bdfa072e6adf2060869e2b970 for
IvyBridge CPUs.

The original commit results in repeated 'Timed out waiting for forcewake old
ack to clear' messages on a Supermicro C7H61 board (BIOS version 2.00 and 2.00b)
with i7-3770K CPU. It ultimately results in a hangup if the system is highly
loaded. Reverting the commit for IvyBridge CPUs fixes the issue.

Issue a warning if the CPU is IvyBridge and mt forcewake is disabled, since
this condition can result in secondary issues.

v2: Only revert patch for Ivybridge CPUs
    Issue info message if mt forcewake is disabled on Ivybridge

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=60541
Cc: Jesse Barnes <bc7add126c2dbb8382bf1c28ac262b9363a32706@virtuousgeek.org>
Cc: Daniel Vetter <c1b6782c4af8f0673da8923a0702a1832e5940f4@ffwll.ch>
Cc: Mika Kuoppala <cd221c71e765d1ce593d15b204fee351fb09fd98@intel.com>
Signed-off-by: Guenter Roeck <ba324ca7b1c77fc20bb970d5aff6eea9377918a5@roeck-us.net>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=66139
Signed-off-by: Daniel Vetter <c1b6782c4af8f0673da8923a0702a1832e5940f4@ffwll.ch>
Signed-off-by: Greg Kroah-Hartman <4645f7897fd33786a2ee1264d590b3c400559d85@linuxfoundation.org>


TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas