tree d01c67b912efc4c183fdbd6850d823ce6ac7401d
parent 86b145ad3efed59e9b5ad4070caf2771d3af1d68
author Seunghwan Kim <sh_.kim@samsung.corp-partner.google.com> 1711950288 +0900
committer Subrata Banik <subratabanik@google.com> 1712211194 +0000

mb/google/brya/var/xol: Reduce power limits according to battery status

When battery level is below critical level or battery is not present,
cpus need to run with a power optimized configuration to avoid platform
instabilities such as system power down.

This will check the current battery status and configure cpu power
limits using current PD power value.

BUG=b:328729536
BRANCH=brya
TEST=built and verified MSR PL2/PL4 values.
     Intel doc #614179 introduces how to check current PL values.

[Original MSR PL1/PL2/PL4 register values for xol]
cd /sys/class/powercap/intel-rapl/intel-rapl\:0/
grep . *power_limit*
  constraint_0_power_limit_uw:15000000 <= MSR PL1 (15W)
  constraint_1_power_limit_uw:55000000 <= MSR PL2 (55W)
  constraint_2_power_limit_uw:114000000 <= MSR PL4 (114W)

[When connected 60W adapter without battery]
Before:
  constraint_0_power_limit_uw:15000000
  constraint_1_power_limit_uw:55000000
  constraint_2_power_limit_uw:114000000
After:
  constraint_0_power_limit_uw:15000000
  constraint_1_power_limit_uw:55000000
  constraint_2_power_limit_uw:60000000

[When connected 45W adapter without battery]
Before:
  constraint_0_power_limit_uw:15000000
  constraint_1_power_limit_uw:55000000
  constraint_2_power_limit_uw:114000000
After:
  constraint_0_power_limit_uw:15000000
  constraint_1_power_limit_uw:45000000
  constraint_2_power_limit_uw:45000000

Change-Id: I5d71e9edde0ecbd7aaf316cd754a6ebcff9da77d
Signed-off-by: Seunghwan Kim <sh_.kim@samsung.corp-partner.google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/81614
Reviewed-by: Jamie Chen <jamie.chen@intel.com>
Reviewed-by: Paul Menzel <paulepanter@mailbox.org>
Reviewed-by: Eric Lai <ericllai@google.com>
Reviewed-by: Sumeet R Pawnikar <sumeet.r.pawnikar@intel.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Subrata Banik <subratabanik@google.com>