feat(mpmm): add support for MPMM
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>
diff --git a/include/lib/fconf/fconf_mpmm_getter.h b/include/lib/fconf/fconf_mpmm_getter.h
new file mode 100644
index 0000000..50d991a
--- /dev/null
+++ b/include/lib/fconf/fconf_mpmm_getter.h
@@ -0,0 +1,20 @@
+/*
+ * Copyright (c) 2021, Arm Limited. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#ifndef FCONF_MPMM_GETTER_H
+#define FCONF_MPMM_GETTER_H
+
+#include <lib/mpmm/mpmm.h>
+
+#define mpmm__config_getter(id) fconf_mpmm_config.id
+
+struct fconf_mpmm_config {
+ const struct mpmm_topology *topology;
+};
+
+extern struct fconf_mpmm_config fconf_mpmm_config;
+
+#endif /* FCONF_MPMM_GETTER_H */
diff --git a/include/lib/mpmm/mpmm.h b/include/lib/mpmm/mpmm.h
new file mode 100644
index 0000000..955c530
--- /dev/null
+++ b/include/lib/mpmm/mpmm.h
@@ -0,0 +1,57 @@
+/*
+ * Copyright (c) 2021, Arm Limited. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#ifndef MPMM_H
+#define MPMM_H
+
+#include <stdbool.h>
+
+#include <platform_def.h>
+
+/*
+ * Enable the Maximum Power Mitigation Mechanism.
+ *
+ * This function will enable MPMM for the current core. The AMU counters
+ * representing the MPMM gears must have been configured and enabled prior to
+ * calling this function.
+ */
+void mpmm_enable(void);
+
+/*
+ * MPMM core data.
+ *
+ * This structure represents per-core data retrieved from the hardware
+ * configuration device tree.
+ */
+struct mpmm_core {
+ /*
+ * Whether MPMM is supported.
+ *
+ * Cores with support for MPMM offer one or more auxiliary AMU counters
+ * representing MPMM gears.
+ */
+ bool supported;
+};
+
+/*
+ * MPMM topology.
+ *
+ * This topology structure describes the system-wide representation of the
+ * information retrieved from the hardware configuration device tree.
+ */
+struct mpmm_topology {
+ struct mpmm_core cores[PLATFORM_CORE_COUNT]; /* Per-core data */
+};
+
+#if !ENABLE_MPMM_FCONF
+/*
+ * Retrieve the platform's MPMM topology. A `NULL` return value is treated as a
+ * non-fatal error, in which case MPMM will not be enabled for any core.
+ */
+const struct mpmm_topology *plat_mpmm_topology(void);
+#endif /* ENABLE_MPMM_FCONF */
+
+#endif /* MPMM_H */