MPMM - the Maximum Power Mitigation Mechanism - is an optional
microarchitectural feature present on some Armv9-A cores, introduced
with the Cortex-X2, Cortex-A710 and Cortex-A510 cores.
MPMM allows the SoC firmware to detect and limit high activity events
to assist in SoC processor power domain dynamic power budgeting and
limit the triggering of whole-rail (i.e. clock chopping) responses to
overcurrent conditions.
This feature is enabled via the `ENABLE_MPMM` build option.
Configuration can be done via FCONF by enabling `ENABLE_MPMM_FCONF`, or
by via the plaform-implemented `plat_mpmm_topology` function.
Change-Id: I77da82808ad4744ece8263f0bf215c5a091c3167
Signed-off-by: Chris Kay <chris.kay@arm.com>
This change makes AMU auxiliary counters configurable on a per-core
basis, controlled by `ENABLE_AMU_AUXILIARY_COUNTERS`.
Auxiliary counters can be described via the `HW_CONFIG` device tree if
the `ENABLE_AMU_FCONF` build option is enabled, or the platform must
otherwise implement the `plat_amu_topology` function.
A new phandle property for `cpu` nodes (`amu`) has been introduced to
the `HW_CONFIG` specification to allow CPUs to describe the view of
their own AMU:
```
cpu0: cpu@0 {
...
amu = <&cpu0_amu>;
};
```
Multiple cores may share an `amu` handle if they implement the
same set of auxiliary counters.
AMU counters are described for one or more AMUs through the use of a new
`amus` node:
```
amus {
cpu0_amu: amu-0 {
#address-cells = <1>;
#size-cells = <0>;
counter@0 {
reg = <0>;
enable-at-el3;
};
counter@n {
reg = <n>;
...
};
};
};
```
This structure describes the **auxiliary** (group 1) AMU counters.
Architected counters have architecturally-defined behaviour, and as
such do not require DTB entries.
These `counter` nodes support two properties:
- The `reg` property represents the counter register index.
- The presence of the `enable-at-el3` property determines whether
the firmware should enable the counter prior to exiting EL3.
Change-Id: Ie43aee010518c5725a3b338a4899b0857caf4c28
Signed-off-by: Chris Kay <chris.kay@arm.com>
Updated the document for BL1 and BL2 boot flow to capture
below changes made in FCONF
1. Loading of fw_config and tb_fw_config images by BL1.
2. Population of fw_config and tb_fw_config by BL2.
Signed-off-by: Manish V Badarkhe <Manish.Badarkhe@arm.com>
Change-Id: Ifea5c61d520ff1de834c279ce1759b53448303ba
Complete the documentation with information on how to write a DTS for
fconf. This patch adds the bindings information for dynamic
configuration properties.
Signed-off-by: Louis Mayencourt <louis.mayencourt@arm.com>
Change-Id: Ic6d9f927df53bb87315c23ec5a8943d0c3258d45
Chris Kay
Manish V Badarkhe
Louis Mayencourt