From 3dd88f175d1863534a8bdb5c19d718becc31e6f3 Mon Sep 17 00:00:00 2001 From: Seunghwan Kim Date: Tue, 27 Feb 2018 14:27:26 +0900 Subject: [PATCH] mb/google/poppy/variant/nautilus: Change SlowSlewRateForSa setting If switch to VT2 on nautilus, screen flicker appears. We found if we rollback the change of slew rate setting, then the flicker issue will be gone: https://review.coreboot.org/c/coreboot/+/22588 But nautilus board needs slew rate tuning to reduce EE noise, so we decided to change only SlowSlewRateForSa to 2 (Fast/8) instead of rollback the whole change of the CL:22588. It can remove the flicker on VT2. BUG=b:71397040 BRANCH=master TEST=emerge-nautilus coreboot Change-Id: Id1d4bd8b1316c02c783de708ec4658e030193a26 Signed-off-by: Seunghwan Kim Reviewed-on: https://review.coreboot.org/23877 Tested-by: build bot (Jenkins) Reviewed-by: Furquan Shaikh --- src/mainboard/google/poppy/variants/nautilus/devicetree.cb | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/src/mainboard/google/poppy/variants/nautilus/devicetree.cb b/src/mainboard/google/poppy/variants/nautilus/devicetree.cb index 3c87b27cf3..0f246859b7 100644 --- a/src/mainboard/google/poppy/variants/nautilus/devicetree.cb +++ b/src/mainboard/google/poppy/variants/nautilus/devicetree.cb @@ -77,7 +77,8 @@ chip soc/intel/skylake register "FastPkgCRampDisableSa" = "1" register "SlowSlewRateForIa" = "3" # Fast/16 register "SlowSlewRateForGt" = "3" # Fast/16 - register "SlowSlewRateForSa" = "3" # Fast/16 + register "SlowSlewRateForSa" = "2" # Fast/8 + # VR Settings Configuration for 4 Domains #+----------------+-------+-------+-------+-------+ #| Domain/Setting | SA | IA | GTUS | GTS |