feat(pmu): introduce pmuv3 lib/extensions folder
The enablement code for the PMU is scattered and difficult to track
down. Factor out the feature into its own lib/extensions folder and
consolidate the implementation. Treat it is as an architecturally
mandatory feature as it is currently.
Additionally, do some cleanup on AArch64. Setting overflow bits in
PMCR_EL0 is irrelevant for firmware so don't do it. Then delay the PMU
initialisation until the context management stage which simplifies the
early environment assembly. One side effect is that the PMU might count
before this happens so reset all counters to 0 to prevent any leakage.
Finally, add an enable to manage_extensions_realm() as realm world uses
the pmu. This introduces the HPMN fixup to realm world.
Signed-off-by: Boyan Karatotev <boyan.karatotev@arm.com>
Change-Id: Ie13a8625820ecc5fbfa467dc6ca18025bf6a9cd3
diff --git a/common/feat_detect.c b/common/feat_detect.c
index 50b74d0..871b52d 100644
--- a/common/feat_detect.c
+++ b/common/feat_detect.c
@@ -144,6 +144,14 @@
check_feature(ENABLE_FEAT_SB, read_feat_sb_id_field(), "SB", 1, 1);
check_feature(ENABLE_FEAT_CSV2_2, read_feat_csv2_id_field(),
"CSV2_2", 2, 3);
+ /*
+ * Even though the PMUv3 is an OPTIONAL feature, it is always
+ * implemented and Arm prescribes so. So assume it will be there and do
+ * away with a flag for it. This is used to check minor PMUv3px
+ * revisions so that we catch them as they come along
+ */
+ check_feature(FEAT_STATE_ALWAYS, read_feat_pmuv3_id_field(),
+ "PMUv3", 1, ID_AA64DFR0_PMUVER_PMUV3P7);
/* v8.1 features */
check_feature(ENABLE_FEAT_PAN, read_feat_pan_id_field(), "PAN", 1, 3);