commit 8fcd3d9600bb2cb6809c6fc68f945ce3ad89633d
author Manish V Badarkhe <Manish.Badarkhe@arm.com> Thu Jul 08 09:33:18 2021 +0100
committer Manish V Badarkhe <Manish.Badarkhe@arm.com> Thu Aug 26 09:32:35 2021 +0100
tree 010d5743de8365662275525396542928a46d152f
parent 5de20ece38f782c8459f546a08c6a97b9e0f5bc5

feat(trf): enable trace filter control register access from lower NS EL

Introduced a build flag 'ENABLE_TRF_FOR_NS' to enable trace filter
control registers access in NS-EL2, or NS-EL1 (when NS-EL2 is
implemented but unused).

Change-Id: If3f53b8173a5573424b9a405a4bd8c206ffdeb8c
Signed-off-by: Manish V Badarkhe <Manish.Badarkhe@arm.com>

lib/el3_runtime/aarch32/context_mgmt.c

diff --git a/lib/el3_runtime/aarch32/context_mgmt.c b/lib/el3_runtime/aarch32/context_mgmt.c
index 2e5b38f..3ef378c 100644
--- a/lib/el3_runtime/aarch32/context_mgmt.c
+++ b/lib/el3_runtime/aarch32/context_mgmt.c
@@ -17,6 +17,7 @@
 #include <lib/el3_runtime/context_mgmt.h>
 #include <lib/extensions/amu.h>
 #include <lib/extensions/sys_reg_trace.h>
+#include <lib/extensions/trf.h>
 #include <lib/utils.h>
 
 /*******************************************************************************
@@ -141,6 +142,10 @@
 #if ENABLE_SYS_REG_TRACE_FOR_NS
 	sys_reg_trace_enable();
 #endif /* ENABLE_SYS_REG_TRACE_FOR_NS */
+
+#if ENABLE_TRF_FOR_NS
+	trf_enable();
+#endif /* ENABLE_TRF_FOR_NS */
 #endif
 }
 

lib/el3_runtime/aarch64/context_mgmt.c

diff --git a/lib/el3_runtime/aarch64/context_mgmt.c b/lib/el3_runtime/aarch64/context_mgmt.c
index 0eb800a..52102dd 100644
--- a/lib/el3_runtime/aarch64/context_mgmt.c
+++ b/lib/el3_runtime/aarch64/context_mgmt.c
@@ -24,6 +24,7 @@
 #include <lib/extensions/sve.h>
 #include <lib/extensions/sys_reg_trace.h>
 #include <lib/extensions/trbe.h>
+#include <lib/extensions/trf.h>
 #include <lib/extensions/twed.h>
 #include <lib/utils.h>
 
@@ -359,6 +360,10 @@
 	sys_reg_trace_enable(ctx);
 #endif /* ENABLE_SYS_REG_TRACE_FOR_NS */
 
+#if ENABLE_TRF_FOR_NS
+	trf_enable();
+#endif /* ENABLE_TRF_FOR_NS */
+
 #endif
 }
 

lib/extensions/trf/aarch32/trf.c

diff --git a/lib/extensions/trf/aarch32/trf.c b/lib/extensions/trf/aarch32/trf.c
new file mode 100644
index 0000000..834092d
--- /dev/null
+++ b/lib/extensions/trf/aarch32/trf.c
@@ -0,0 +1,35 @@
+/*
+ * Copyright (c) 2021, Arm Limited. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <stdbool.h>
+
+#include <arch.h>
+#include <arch_helpers.h>
+#include <lib/extensions/trf.h>
+
+static bool trf_supported(void)
+{
+	uint32_t features;
+
+	features = read_id_dfr0() >> ID_DFR0_TRACEFILT_SHIFT;
+	return ((features & ID_DFR0_TRACEFILT_MASK) ==
+		ID_DFR0_TRACEFILT_SUPPORTED);
+}
+
+void trf_enable(void)
+{
+	uint32_t val;
+
+	if (trf_supported()) {
+		/*
+		 * Allow access of trace filter control registers from
+		 * non-monitor mode
+		 */
+		val = read_sdcr();
+		val &= ~SDCR_TTRF_BIT;
+		write_sdcr(val);
+	}
+}

lib/extensions/trf/aarch64/trf.c

diff --git a/lib/extensions/trf/aarch64/trf.c b/lib/extensions/trf/aarch64/trf.c
new file mode 100644
index 0000000..1da5dce
--- /dev/null
+++ b/lib/extensions/trf/aarch64/trf.c
@@ -0,0 +1,36 @@
+/*
+ * Copyright (c) 2021, Arm Limited. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <stdbool.h>
+
+#include <arch.h>
+#include <arch_helpers.h>
+#include <lib/extensions/trf.h>
+
+static bool trf_supported(void)
+{
+	uint64_t features;
+
+	features = read_id_aa64dfr0_el1() >> ID_AA64DFR0_TRACEFILT_SHIFT;
+	return ((features & ID_AA64DFR0_TRACEFILT_MASK) ==
+		ID_AA64DFR0_TRACEFILT_SUPPORTED);
+}
+
+void trf_enable(void)
+{
+	uint64_t val;
+
+	if (trf_supported()) {
+		/*
+		 * MDCR_EL3.TTRF = b0
+		 * Allow access of trace filter control registers from NS-EL2
+		 * and NS-EL1 when NS-EL2 is implemented but not used
+		 */
+		val = read_mdcr_el3();
+		val &= ~MDCR_TTRF_BIT;
+		write_mdcr_el3(val);
+	}
+}