Commit b2d2fe39 authored by Artem Bityutskiy's avatar Artem Bityutskiy Committed by Jun Tian
Browse files

intel_idle: add SnowRidge C-state table

mainline inclusion
from mainline-v5.11-rc2
commit 9cf93f05
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I5BECY


CVE: NA

Intel-SIG: commit 9cf93f05 intel_idle: add SnowRidge C-state table.
Backport intel_idle driver

--------------------------------

Add C-state table for the SnowRidge SoC which is found on Intel Jacobsville
platforms.

The following has been changed.

 1. C1E latency changed from 10us to 15us. It was measured using the
    open source "wult" tool (the "nic" method, 15us is the 99.99th
    percentile).

 2. C1E power break even changed from 20us to 25us, which may result
    in less C1E residency in some workloads.

 3. C6 latency changed from 50us to 130us. Measured the same way as C1E.

The C6 C-state is supported only by some SnowRidge revisions, so add a C-state
table commentary about this.

On SnowRidge, C6 support is enumerated via the usual mechanism: "mwait" leaf of
the "cpuid" instruction. The 'intel_idle' driver does check this leaf, so even
though C6 is present in the table, the driver will only use it if the CPU does
support it.

Signed-off-by: default avatarArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: default avataryingbao jia <yingbao.jia@intel.com>
Signed-off-by: default avatarJun Tian <jun.j.tian@intel.com>
parent dbf4fd06
Loading
Loading
Loading
Loading
0% Loading or .
You are about to add 0 people to the discussion. Proceed with caution.
Please to comment