From a4cdb5b381c92079ad7dae68b02599f3e7cec063 Mon Sep 17 00:00:00 2001 From: MAULIK V VAGHELA Date: Mon, 7 Mar 2022 09:55:52 +0530 Subject: [PATCH] mb/google/brya: Disable C1-state auto demotion for Brya & Brask C1-state auto demotion feature allows hardware to determine C1-state as per platform policy. Since Brya sets performance policy to balanced from hardware, auto demotion can be disabled without performance impact. Also, disabling this feature results in 110 mW power savings during video playback. Note that C1state Autodemotion feature is not applicable for ADL-P SoC. Hence recommendation is to keep it disabled. BUG=b:221876248 BRANCH=firmware-brya-14505.B TEST=Code compiles and correct value of c1-state auto demotion is passed to FSP. Also power and performance impact has been measure by respective teams. Change-Id: I41eea916cdfe4a86e4d263e3191f5cb40fa33a90 Signed-off-by: Maulik V Vaghela Reviewed-on: https://review.coreboot.org/c/coreboot/+/62630 Tested-by: build bot (Jenkins) Reviewed-by: Nick Vaccaro Reviewed-by: Tim Wawrzynczak Reviewed-by: Subrata Banik Reviewed-by: Sridhar Siricilla --- .../google/brya/variants/baseboard/brask/devicetree.cb | 3 +++ .../google/brya/variants/baseboard/brya/devicetree.cb | 3 +++ 2 files changed, 6 insertions(+) diff --git a/src/mainboard/google/brya/variants/baseboard/brask/devicetree.cb b/src/mainboard/google/brya/variants/baseboard/brask/devicetree.cb index a57289b46a..0d60a57201 100644 --- a/src/mainboard/google/brya/variants/baseboard/brask/devicetree.cb +++ b/src/mainboard/google/brya/variants/baseboard/brask/devicetree.cb @@ -76,6 +76,9 @@ chip soc/intel/alderlake # FIVR RFI Spread Spectrum 1.5% register "fivr_spread_spectrum" = "FIVR_SS_1_5" + # Disable C state auto-demotion for all brask baseboards + register "disable_c1_state_auto_demotion" = "1" + # Intel Common SoC Config #+-------------------+---------------------------+ #| Field | Value | diff --git a/src/mainboard/google/brya/variants/baseboard/brya/devicetree.cb b/src/mainboard/google/brya/variants/baseboard/brya/devicetree.cb index 9ceda11873..c75f321861 100644 --- a/src/mainboard/google/brya/variants/baseboard/brya/devicetree.cb +++ b/src/mainboard/google/brya/variants/baseboard/brya/devicetree.cb @@ -72,6 +72,9 @@ chip soc/intel/alderlake # FIVR RFI Spread Spectrum 1.5% register "fivr_spread_spectrum" = "FIVR_SS_1_5" + # Disable C state auto-demotion for all brya baseboards + register "disable_c1_state_auto_demotion" = "1" + # Intel Common SoC Config #+-------------------+---------------------------+ #| Field | Value |