feat(rng-trap): add EL3 support for FEAT_RNG_TRAP
FEAT_RNG_TRAP introduces support for EL3 trapping of reads of the
RNDR and RNDRRS registers, which is enabled by setting the
SCR_EL3.TRNDR bit. This patch adds a new build flag
ENABLE_FEAT_RNG_TRAP that enables the feature.
This feature is supported only in AArch64 state from Armv8.5 onwards.
Signed-off-by: Juan Pablo Conde <juanpablo.conde@arm.com>
Change-Id: Ia9f17aef3444d3822bf03809036a1f668c9f2d89
diff --git a/common/feat_detect.c b/common/feat_detect.c
index be3e20e..ee34588 100644
--- a/common/feat_detect.c
+++ b/common/feat_detect.c
@@ -254,6 +254,16 @@
#endif
}
+/******************************************************************
+ * Feature : FEAT_RNG_TRAP (Trapping support for RNDR/RNDRRS)
+ *****************************************************************/
+static void read_feat_rng_trap(void)
+{
+#if (ENABLE_FEAT_RNG_TRAP == FEAT_STATE_1)
+ feat_detect_panic(is_feat_rng_trap_present(), "RNG_TRAP");
+#endif
+}
+
/***********************************************************************************
* TF-A supports many Arm architectural features starting from arch version
* (8.0 till 8.7+). These features are mostly enabled through build flags. This
@@ -304,6 +314,7 @@
read_feat_mte();
read_feat_rng();
read_feat_bti();
+ read_feat_rng_trap();
/* v8.6 features */
read_feat_amuv1p1();