refactor(cpufeat): separate the EL2 and EL3 enablement code
Combining the EL2 and EL3 enablement code necessitates that it must be
called at el3_exit, which is the only place with enough context to make
the decision of what needs to be set.
Decouple them to allow them to be called from elsewhere.
Signed-off-by: Boyan Karatotev <boyan.karatotev@arm.com>
Change-Id: I147764c42771e7d4100699ec8fae98dac0a505c0
diff --git a/lib/extensions/trbe/trbe.c b/lib/extensions/trbe/trbe.c
index fa139ca..461ea73 100644
--- a/lib/extensions/trbe/trbe.c
+++ b/lib/extensions/trbe/trbe.c
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2021-2022, Arm Limited. All rights reserved.
+ * Copyright (c) 2021-2023, Arm Limited. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
@@ -19,9 +19,9 @@
__asm__ volatile("hint #18");
}
-void trbe_enable(void)
+void trbe_init_el3(void)
{
- uint64_t val;
+ u_register_t val;
/*
* MDCR_EL3.NSTB = 0b11
@@ -34,6 +34,17 @@
write_mdcr_el3(val);
}
+void trbe_init_el2_unused(void)
+{
+ /*
+ * MDCR_EL2.E2TB: Set to zero so that the trace Buffer
+ * owning exception level is NS-EL1 and, tracing is
+ * prohibited at NS-EL2. These bits are RES0 when
+ * FEAT_TRBE is not implemented.
+ */
+ write_mdcr_el2(read_mdcr_el2() & ~MDCR_EL2_E2TB(MDCR_EL2_E2TB_EL1));
+}
+
static void *trbe_drain_trace_buffers_hook(const void *arg __unused)
{
if (is_feat_trbe_supported()) {