the following patch was just integrated into master: commit 364dbdd0177ff1fb5bbf398217fcae01ef296d1e Author: Duncan Laurie dlaurie@chromium.org Date: Mon Jun 25 09:51:59 2012 -0700
CPU: Add basic support for Nominal Configurable TDP
Ivybridge B0+ CPUs are capable of supporting multiple TDP levels. This complicates the default case because now the registers that were reporting max non-turbo ratio are reporting that value for the highest possible TDP level.
For now this change just forces everything to use the Nominal TDP values instead of the higher (or lower) levels.
- When building P-state tables, determine the P[1] (max non turbo) ratio based on the Nominal ratio if available. - Set the turbo activation ratio to the Nominal max ratio. - Mirror the power level settings in new MCHBAR register after they are written, which happens after BIOS_RESET_CPL is set. - Set the current ratio to Nominal ratio at boot.
1) Verify that P-state table is generated properly with P[0]=1801MHz (ratio 0x1C) and P[1]=1800MHz (ratio 0x12)
PSS: 1801MHz power 17000 control 0x1c00 status 0x1c00 PSS: 1800MHz power 17000 control 0x1200 status 0x1200
2) Verify power limits in MCHBAR match PKG_POWER_LIMIT:
> rdmsr 0 0x610 0x800080aa00dc8088 > mmio_read32 0xfed159a4 0x000080aa > mmio_read32 0xfed159a0 0x00dc8088
3) Verify turbo activation ratio is set to nominal ratio:
> rdmsr 0 0x64c 0x0000000000000012
4) Check that proper ratio was set at boot on one core only:
> grep 'frequency set to' /sys/firmware/log model_x06ax: frequency set to 1800 model_x06ax: frequency set to 1800 model_x06ax: frequency set to 1800 model_x06ax: frequency set to 1800
Change-Id: I592e60a7740f31b140986a8269dca91b4adbb270 Signed-off-by: Duncan Laurie dlaurie@chromium.org
Build-Tested: build bot (Jenkins) at Tue Jul 24 12:57:13 2012, giving +1 Reviewed-By: Ronald G. Minnich rminnich@gmail.com at Tue Jul 24 23:39:44 2012, giving +2 See http://review.coreboot.org/1304 for details.
-gerrit