Update documentation for using the tool to support performance level change via OOB (Out of Band) interface. Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@xxxxxxxxxxxxxxx> --- v2: As suggested by Jonathan - Indent literal block - Show output of command .../admin-guide/pm/intel-speed-select.rst | 22 +++++++++++++++++++ 1 file changed, 22 insertions(+) diff --git a/Documentation/admin-guide/pm/intel-speed-select.rst b/Documentation/admin-guide/pm/intel-speed-select.rst index 0a1fbdb54bfe..a2bfb971654f 100644 --- a/Documentation/admin-guide/pm/intel-speed-select.rst +++ b/Documentation/admin-guide/pm/intel-speed-select.rst @@ -262,6 +262,28 @@ Which shows that the base frequency now increased from 2600 MHz at performance level 0 to 2800 MHz at performance level 4. As a result, any workload, which can use fewer CPUs, can see a boost of 200 MHz compared to performance level 0. +Changing performance level via BMC Interface +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +It is possible to change SST-PP level using out of band (OOB) agent (Via some +remote management console, through BMC "Baseboard Management Controller" +interface). This mode is supported from the Sapphire Rapids processor +generation. The kernel and tool change to support this mode is added to Linux +kernel version 5.18. To enable this feature, kernel config +"CONFIG_INTEL_HFI_THERMAL" is required. The minimum version of the tool +is "v1.12" to support this feature, which is part of Linux kernel version 5.18. + +To support such configuration, this tool can be used as a daemon. Add +a command line option --oob:: + + # intel-speed-select --oob + Intel(R) Speed Select Technology + Executing on CPU model:143[0x8f] + OOB mode is enabled and will run as daemon + +In this mode the tool will online/offline CPUs based on the new performance +level. + Check presence of other Intel(R) SST features --------------------------------------------- -- 2.35.1
