ISSUE
=====
Ivybridge system fails to resume from S3/S4 with recent BIOS. On system resume causes kernel oops in i915 driver.
FIX
===
Upstream fixed the issue by adding multi-threaded forcewake support.
On IVB C0+ with newer BIOSes, the forcewake handshake has changed. There's
now a bitfield for different driver components to keep the GT powered
on. On Linux, we centralize forcewake handling in one place, so we
still just need a single bit, but we need to use the new registers if MT
forcewake is enabled.
SRU JUSTIFICATION
================
ISSUE
=====
Ivybridge system fails to resume from S3/S4 with recent BIOS. On system resume causes kernel oops in i915 driver.
FIX
===
Upstream fixed the issue by adding multi-threaded forcewake support.
On IVB C0+ with newer BIOSes, the forcewake handshake has changed. There's
now a bitfield for different driver components to keep the GT powered
on. On Linux, we centralize forcewake handling in one place, so we
still just need a single bit, but we need to use the new registers if MT
forcewake is enabled.
TEST kernel. ubuntu. com/~sarvatt/ fdo42923/ and the test results are noted in comment #3 in this bug, and also reported the same to https:/ /bugs.freedeskt op.org/ show_bug. cgi?id= 42923
=====
This patch was tested on Ivybridge system with the kernel posted at http://