History log of /linux-master/drivers/platform/x86/intel/uncore-frequency/uncore-frequency-tpmi.c
Revision Date Author Comments
# db643cb7 15-Apr-2024 Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>

platform/x86/intel-uncore-freq: Don't present root domain on error

If none of the clusters are added because of some error, fail to load
driver without presenting root domain. In this case root domain will
present invalid data.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Fixes: 01c10f88c9b7 ("platform/x86/intel-uncore-freq: tpmi: Provide cluster level control")
Cc: <stable@vger.kernel.org> # 6.5+
Link: https://lore.kernel.org/r/20240415215210.2824868-1-srinivas.pandruvada@linux.intel.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>


# bc774d46 15-Apr-2024 Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>

platform/x86/intel-uncore-freq: Increase minor number support

No new changes will be added for minor version 2. Change the minor
version number to 2 and stop displaying log message for unsupported
minor version 2.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Link: https://lore.kernel.org/r/20240415220625.2828339-1-srinivas.pandruvada@linux.intel.com
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>


# b06458d1 04-Dec-2023 Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>

platform/x86/intel-uncore-freq: Process read/write blocked feature status

When a feature is read blocked, don't continue to read uncore information
and register with uncore core.

When the feature is write blocked, continue to offer read interface but
block setting uncore limits.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20231204221740.3645130-6-srinivas.pandruvada@linux.intel.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>


# 4b0d9c8f 03-Oct-2023 Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>

platform/x86/intel-uncore-freq: Ignore minor version change

The hardware definition of every TPMI feature contains a major and minor
version. When there is a change in the MMIO offset or change in the
definition of a field, hardware will change major version. For addition
of new fields without modifying existing MMIO offsets or fields, only the
minor version is changed.

Driver is developed to support uncore frequency control (UFS) for a major
and minor version. If the hardware changes major version, since offsets
and definitions are changed, driver cannot continue to provide UFS
interface to users. Driver can still function with minor version change
as it will just miss the new functionality added by the hardware.

The current implementation logs information message and skips adding
uncore sysfs entry for a resource for any version mismatch. Check major
and minor version mismatch for every valid resource and fail on any major
version mismatch by logging an error message. A valid resource has a
version which is not 0xFF.

If there is mismatch with the minor version, continue with a log message.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Link: https://lore.kernel.org/r/20231003184916.1860084-4-srinivas.pandruvada@linux.intel.com
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>


# 01c10f88 18-Apr-2023 Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>

platform/x86/intel-uncore-freq: tpmi: Provide cluster level control

The new generation of CPUs have granular control at a cluster level.
Each package/die can have multiple power domains, which further can
have multiple fabric clusters. The TPMI interface allows control at
fabric cluster level.

Use the updated uncore sysfs feature to expose controls at cluster
level. At each cluster level there is a control for maximum and minimum
uncore frequency. Also present current uncore frequency at a cluster
level.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Reviewed-by: Zhang Rui <rui.zhang@intel.com>
Tested-by: Wendy Wang <wendy.wang@intel.com>
Link: https://lore.kernel.org/r/20230418171340.681662-4-srinivas.pandruvada@linux.intel.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>


# 8a54e225 20-Apr-2023 Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>

platform/x86/intel-uncore-freq: Uncore frequency control via TPMI

Implement support of uncore frequency control via TPMI (Topology Aware
Register and PM Capsule Interface). This driver provides the similar
functionality as the current uncore frequency driver using MSRs.

The hardware interface to read/write is basically substitution of MSR
0x620 and 0x621. There are specific MMIO offset and bits to get/set
minimum and maximum uncore ratio, similar to MSRs.

The scope of the uncore MSRs is package/die. But new generation of CPUs
have more granular control at a cluster level. Each package/die can have
multiple power domains, which further can have multiple clusters. The
TPMI interface allows control at cluster level.

The primary use case for uncore sysfs is to set maximum and minimum
uncore frequency to reduce power consumption or latency. The current
uncore sysfs control is per package/die. This is enough for the majority
of users as workload will move to different power domains as it moves
between different CPUs.

The current uncore sysfs provides controls at package/die level. When
user sets maximum/minimum limits, the driver sets the same limits to
each cluster.

Here number of power domains = number of resources in this aux device.
There are offsets and bits to discover number of clusters and offset for
each cluster level controls.

The TPMI documentation can be downloaded from:
https://github.com/intel/tpmi_power_management

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Reviewed-by: Zhang Rui <rui.zhang@intel.com>
Tested-by: Wendy Wang <wendy.wang@intel.com>
Link: https://lore.kernel.org/r/20230420220514.747573-1-srinivas.pandruvada@linux.intel.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>