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authorSukumar Ghorai <sukumar.ghorai@intel.com>2023-12-01 11:32:42 -0800
committerSubrata Banik <subratabanik@google.com>2023-12-16 15:34:12 +0000
commit1c295092d61c2ac7427ddac6d194d99337f86094 (patch)
tree9e111bc2f351e2ac61b7d8f3adcdc89a5487fef4 /src
parent0c8d64cc63bfb05bae42ff9ddcf99269338dd64a (diff)
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 <sukumar.ghorai@intel.com> Reviewed-on: https://review.coreboot.org/c/coreboot/+/79386 Reviewed-by: Jakub Czapiga <czapiga@google.com> Reviewed-by: Sumeet R Pawnikar <sumeet.r.pawnikar@intel.com> Reviewed-by: Subrata Banik <subratabanik@google.com> Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Diffstat (limited to 'src')
-rw-r--r--src/mainboard/google/rex/variants/baseboard/ovis/devicetree.cb4
-rw-r--r--src/mainboard/google/rex/variants/baseboard/rex/devicetree.cb4
2 files changed, 8 insertions, 0 deletions
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"