platform/x86: ISST: Add SST-BF support via TPMI
The Intel Speed Select Technology - Base Frequency (SST-BF) feature lets
the user control base frequency. If some critical workload threads demand
constant high guaranteed performance, then this feature can be used to
execute the thread at higher base frequency on specific sets of CPUs
(high priority CPUs) at the cost of lower base frequency (low priority
CPUs) on other CPUs.
Two new IOCTLs are added:
ISST_IF_GET_BASE_FREQ_INFO : Get frequency information for high and
low priority CPUs
ISST_IF_GET_BASE_FREQ_CPU_MASK : CPUs capable of higher frequency
Once an instance is identified, read or write from correct MMIO
offset for a given field as defined in the specification.
For details on SST-BF operations using intel-speed-selet utility,
refer to:
Documentation/admin-guide/pm/intel-speed-select.rst
under the kernel documentation
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Reviewed-by: Zhang Rui <rui.zhang@intel.com>
Tested-by: Pragya Tanwar <pragya.tanwar@intel.com>
Link: https://lore.kernel.org/r/20230308070642.1727167-7-srinivas.pandruvada@linux.intel.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>