Set kparam intel_idle.max_cstate=7 for SKL systems.
cstates higher than 7 allow assertion of SLP_SO# signal which in turn
affects PMIC entering certain low-power modes which may be a source of
platform instability. Disabling it for now.
BUG=chrome-os-partner:57920
CQ-DEPEND=CL:*298876
TEST=manual,
./build_packages --board=chell
./build_image --board=chell test
cros flash ...
cat /proc/cmdline
<contains intel_idle.max_cstate=7>
Turn off display via turning backlight to zero.
Examine SLP_S0# signal no longer asserts
Change-Id: I19a067f08af98213c63a602b99d554efc5b64a7d
Reviewed-on: https://chromium-review.googlesource.com/401480
Commit-Queue: Todd Broch <tbroch@chromium.org>
Tested-by: Todd Broch <tbroch@chromium.org>
Reviewed-by: Mike Frysinger <vapier@chromium.org>
1 file changed