AMU: Add plat interface to select which group 1 counters to enable
A new platform macro `PLAT_AMU_GROUP1_COUNTERS_MASK` controls which
group 1 counters should be enabled. The maximum number of group 1
counters supported by AMUv1 is 16 so the mask can be at most 0xffff.
If the platform does not define this mask, no group 1 counters are
enabled.
A related platform macro `PLAT_AMU_GROUP1_NR_COUNTERS` is used by
generic code to allocate an array to save and restore the counters on
CPU suspend.
Change-Id: I6d135badf4846292de931a43bb563077f42bb47b
Signed-off-by: Dimitris Papastamos <dimitris.papastamos@arm.com>
diff --git a/docs/porting-guide.rst b/docs/porting-guide.rst
index f020ec9..51d2e64 100644
--- a/docs/porting-guide.rst
+++ b/docs/porting-guide.rst
@@ -549,6 +549,22 @@
doesn't print anything to the console. If ``PLAT_LOG_LEVEL_ASSERT`` isn't
defined, it defaults to ``LOG_LEVEL``.
+If the platform port uses the Activity Monitor Unit, the following constants
+may be defined:
+
+- **PLAT\_AMU\_GROUP1\_COUNTERS\_MASK**
+ This mask reflects the set of group counters that should be enabled. The
+ maximum number of group 1 counters supported by AMUv1 is 16 so the mask
+ can be at most 0xffff. If the platform does not define this mask, no group 1
+ counters are enabled. If the platform defines this mask, the following
+ constant needs to also be defined.
+
+- **PLAT\_AMU\_GROUP1\_NR\_COUNTERS**
+ This value is used to allocate an array to save and restore the counters
+ specified by ``PLAT_AMU_GROUP1_COUNTERS_MASK`` on CPU suspend.
+ This value should be equal to the highest bit position set in the
+ mask, plus 1. The maximum number of group 1 counters in AMUv1 is 16.
+
File : plat\_macros.S [mandatory]
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
diff --git a/include/lib/extensions/amu.h b/include/lib/extensions/amu.h
index bbefe8f..2ecbea5 100644
--- a/include/lib/extensions/amu.h
+++ b/include/lib/extensions/amu.h
@@ -7,9 +7,28 @@
#ifndef __AMU_H__
#define __AMU_H__
-/* Enable all group 0 counters */
+#include <sys/cdefs.h> /* for CASSERT() */
+#include <cassert.h>
+#include <platform_def.h>
+
+/* All group 0 counters */
#define AMU_GROUP0_COUNTERS_MASK 0xf
+#ifdef PLAT_AMU_GROUP1_COUNTERS_MASK
+#define AMU_GROUP1_COUNTERS_MASK PLAT_AMU_GROUP1_COUNTERS_MASK
+#else
+#define AMU_GROUP1_COUNTERS_MASK 0
+#endif
+
+#ifdef PLAT_AMU_GROUP1_NR_COUNTERS
+#define AMU_GROUP1_NR_COUNTERS PLAT_AMU_GROUP1_NR_COUNTERS
+#else
+#define AMU_GROUP1_NR_COUNTERS 0
+#endif
+
+CASSERT(AMU_GROUP1_COUNTERS_MASK <= 0xffff, invalid_amu_group1_counters_mask);
+CASSERT(AMU_GROUP1_NR_COUNTERS <= 16, invalid_amu_group1_nr_counters);
+
void amu_enable(int el2_unused);
#endif /* __AMU_H__ */
diff --git a/lib/extensions/amu/aarch64/amu.c b/lib/extensions/amu/aarch64/amu.c
index 007b349..c00aa5a 100644
--- a/lib/extensions/amu/aarch64/amu.c
+++ b/lib/extensions/amu/aarch64/amu.c
@@ -36,5 +36,7 @@
/* Enable group 0 counters */
write_amcntenset0_el0(AMU_GROUP0_COUNTERS_MASK);
+ /* Enable group 1 counters */
+ write_amcntenset1_el0(AMU_GROUP1_COUNTERS_MASK);
}
}