From 1c295092d61c2ac7427ddac6d194d99337f86094 Mon Sep 17 00:00:00 2001 From: Sukumar Ghorai Date: Fri, 1 Dec 2023 11:32:42 -0800 Subject: [PATCH] mb/google/{rex,ovis}: Decrease EPP to 45% for MTL performance expectation The default EPP is set at 50%, which is deemed insufficiently aggressive for meeting the MTL performance expectations in balance_performance mode. # cat /sys/devices/system/cpu/cpu0/cpufreq/energy_performance_preference balance_performance # iotools rdmsr 0 0x774 0x0000000080003f06 EPP=45% is giving the required performance in MTL. # iotools rdmsr 0 0x774 0x0000000073003d06 NOTE: Kernel changes are necessary to ensure that the EPP (Energy Performance Preference) configured in the BIOS is not overwritten: https://patchwork.kernel.org/patch/13461932 BUG=b:314275133 TEST=Build and boot. Change-Id: I1953994cdb4e9363fdd4b4728e3e5236276c06c8 Signed-off-by: Sukumar Ghorai Reviewed-on: https://review.coreboot.org/c/coreboot/+/79386 Reviewed-by: Jakub Czapiga Reviewed-by: Sumeet R Pawnikar Reviewed-by: Subrata Banik Tested-by: build bot (Jenkins) --- .../google/rex/variants/baseboard/ovis/devicetree.cb | 4 ++++ src/mainboard/google/rex/variants/baseboard/rex/devicetree.cb | 4 ++++ 2 files changed, 8 insertions(+) diff --git a/src/mainboard/google/rex/variants/baseboard/ovis/devicetree.cb b/src/mainboard/google/rex/variants/baseboard/ovis/devicetree.cb index 3f75b709da..aace5adcf4 100644 --- a/src/mainboard/google/rex/variants/baseboard/ovis/devicetree.cb +++ b/src/mainboard/google/rex/variants/baseboard/ovis/devicetree.cb @@ -65,6 +65,10 @@ chip soc/intel/meteorlake register "sagv_freq_mhz[3]" = "6400" register "sagv_gear[3]" = "4" + # set EPP to 45%: 45 * 256/100 = 115 = 0x73 + register "enable_energy_perf_pref" = "true" + register "energy_perf_pref_value" = "0x73" + # Set on-board graphics as primary display register "skip_ext_gfx_scan" = "1" diff --git a/src/mainboard/google/rex/variants/baseboard/rex/devicetree.cb b/src/mainboard/google/rex/variants/baseboard/rex/devicetree.cb index 162bb64a47..9f868406a1 100644 --- a/src/mainboard/google/rex/variants/baseboard/rex/devicetree.cb +++ b/src/mainboard/google/rex/variants/baseboard/rex/devicetree.cb @@ -62,6 +62,10 @@ chip soc/intel/meteorlake register "sagv_freq_mhz[3]" = "6400" register "sagv_gear[3]" = "4" + # set EPP to 45%: 45 * 256/100 = 115 = 0x73 + register "enable_energy_perf_pref" = "true" + register "energy_perf_pref_value" = "0x73" + # Set on-board graphics as primary display register "skip_ext_gfx_scan" = "1"