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author | Arthur Heymans <arthur@aheymans.xyz> | 2016-10-06 12:14:14 +0200 |
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committer | Martin Roth <martinroth@google.com> | 2016-10-09 21:37:50 +0200 |
commit | aacd548c26f251583f1035d4ecc544198721f937 (patch) | |
tree | 0b27dc4487e846b6b6568f402cefd6963e478592 /src/arch/riscv/boot.c | |
parent | e7aeb2f60212077521f7d71a4f485c8f4a26f6c6 (diff) |
cpu/intel/model_6ex: Set msr bits for dynamic L2, C2E, C4E
The datasheets "Intel® Core™ Duo Processor and Intel® Core™ Solo
Processor on 65 nm Process" mentions cpu C-states substates which can
either be attained by adding a substate hint to the MWAIT/P_LVLx request
or automatically by setting some msr bits correctly.
This just sets the same msr bits as model_6fx to enable
dynamic L2 cache, C2E and C4E acpi cpu states.
The result is that when limiting a thinkpad x60 with a yonah T2400
cpu to the acpi cpu C2 state, the idle power usage drops from 18W to
14W. When the lowest C-state is set to C4 the idle power usage seems
to remain similar.
Change-Id: I6c422656ace04659f32082a5944617eda6c79ec3
Signed-off-by: Arthur Heymans <arthur@aheymans.xyz>
Reviewed-on: https://review.coreboot.org/16901
Tested-by: build bot (Jenkins)
Reviewed-by: Martin Roth <martinroth@google.com>
Diffstat (limited to 'src/arch/riscv/boot.c')
0 files changed, 0 insertions, 0 deletions