test: Add rng_benchmark test

BRANCH=none
BUG=b:246836252
TEST=./test/run_device_tests.py --board bloonchipper -t rng_benchmark
TEST=./test/run_device_tests.py --board dartmonkey -t rng_benchmark

Signed-off-by: Andrea Grandi <agrandi@google.com>
Change-Id: Ib1a2a4b0fc8e3d55022e94727417c38e5e94359b
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/4019773
Reviewed-by: Bobby Casey <bobbycasey@google.com>
Code-Coverage: Zoss <zoss-cl-coverage@prod.google.com>
Reviewed-by: Tom Hughes <tomhughes@chromium.org>

9 files changed, 97 insertions, 0 deletions

diff --git a/board/hatch_fp/build.mk b/board/hatch_fp/build.mk
index 541ac5f198..894c907ab9 100644
--- a/board/hatch_fp/build.mk
+++ b/board/hatch_fp/build.mk
@@ -49,6 +49,7 @@ test-list-y=\
        pingpong \
        printf \
        queue \
+       rng_benchmark \
        rollback \
        rollback_entropy \
        rsa3 \
diff --git a/board/nocturne_fp/build.mk b/board/nocturne_fp/build.mk
index 1d8e9174f7..2bc59c1f13 100644
--- a/board/nocturne_fp/build.mk
+++ b/board/nocturne_fp/build.mk
@@ -49,6 +49,7 @@ test-list-y=\
        pingpong \
        printf \
        queue \
+       rng_benchmark \
        rollback \
        rollback_entropy \
        rsa3 \
diff --git a/board/nucleo-dartmonkey/build.mk b/board/nucleo-dartmonkey/build.mk
index 809db95260..b544490fc9 100644
--- a/board/nucleo-dartmonkey/build.mk
+++ b/board/nucleo-dartmonkey/build.mk
@@ -28,6 +28,7 @@ test-list-y=\
        pingpong \
        printf \
        queue \
+       rng_benchmark \
        rollback \
        rollback_entropy \
        rsa3 \
diff --git a/board/nucleo-f412zg/build.mk b/board/nucleo-f412zg/build.mk
index 37402b7e68..d923a7a40f 100644
--- a/board/nucleo-f412zg/build.mk
+++ b/board/nucleo-f412zg/build.mk
@@ -25,6 +25,7 @@ test-list-y=\
        pingpong \
        printf \
        queue \
+       rng_benchmark \
        rollback \
        rollback_entropy \
        rsa3 \
diff --git a/board/nucleo-h743zi/build.mk b/board/nucleo-h743zi/build.mk
index 3a59c5d47d..ad04a68918 100644
--- a/board/nucleo-h743zi/build.mk
+++ b/board/nucleo-h743zi/build.mk
@@ -25,6 +25,7 @@ test-list-y=\
        pingpong \
        printf \
        queue \
+       rng_benchmark \
        rollback \
        rollback_entropy \
        rsa3 \
diff --git a/test/build.mk b/test/build.mk
index 384ad60a59..30908d309e 100644
--- a/test/build.mk
+++ b/test/build.mk
@@ -237,6 +237,7 @@ power_button-y=power_button.o
 powerdemo-y=powerdemo.o
 printf-y=printf.o
 queue-y=queue.o
+rng_benchmark-y=rng_benchmark.o
 rollback-y=rollback.o
 rollback_entropy-y=rollback_entropy.o
 rollback_secret-y=rollback_secret.o
diff --git a/test/rng_benchmark.cc b/test/rng_benchmark.cc
new file mode 100644
index 0000000000..2e47b8ea27
--- /dev/null
+++ b/test/rng_benchmark.cc
@@ -0,0 +1,81 @@
+/* Copyright 2022 The ChromiumOS Authors
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ *
+ * Measure performance of the hardware True Random Number Generator (TRNG)
+ * compared to the std::rand().
+ */
+
+#include "benchmark.h"
+
+#include "console.h"
+#include <array>
+#include <cstdint>
+#include <cstdlib>
+
+extern "C" {
+#include "test_util.h"
+#include "trng.h"
+}
+
+test_static int test_rng()
+{
+	constexpr int num_iterations = 100;
+	Benchmark benchmark({ .num_iterations = num_iterations });
+	std::array<uint32_t, num_iterations> trng_out;
+	std::array<int, num_iterations> rand_out;
+
+	// Try the hardware true random number generator
+	trng_out.fill(0);
+
+	trng_init();
+	auto result = benchmark.run("trng", [&trng_out]() {
+		static int i = 0;
+		trng_out[i++] = trng_rand();
+	});
+	trng_exit();
+
+	TEST_ASSERT(result.has_value());
+	for (int i = 0; i < trng_out.size() - 1; ++i) {
+		TEST_NE(trng_out[i], trng_out[i + 1], "%d");
+		cflush();
+	}
+
+	// Repeat the test by turning the TNRG on and off at each iteration
+	trng_out.fill(0);
+	result = benchmark.run("trng_on_off", [&trng_out]() {
+		trng_init();
+		static int i = 0;
+		trng_out[i++] = trng_rand();
+		trng_exit();
+	});
+
+	TEST_ASSERT(result.has_value());
+	for (int i = 0; i < trng_out.size() - 1; ++i) {
+		TEST_NE(trng_out[i], trng_out[i + 1], "%d");
+		cflush();
+	}
+
+	// Repeat the test using std::rand() for comparison
+	rand_out.fill(0);
+	result = benchmark.run("std::rand", [&rand_out]() {
+		static int i = 0;
+		rand_out[i++] = std::rand();
+	});
+
+	TEST_ASSERT(result.has_value());
+	for (int i = 0; i < rand_out.size() - 1; ++i) {
+		TEST_NE(rand_out[i], rand_out[i + 1], "%d");
+		cflush();
+	}
+
+	benchmark.print_results();
+	return EC_SUCCESS;
+}
+
+void run_test(int argc, const char **argv)
+{
+	test_reset();
+	RUN_TEST(test_rng);
+	test_print_result();
+}
\ No newline at end of file
diff --git a/test/rng_benchmark.tasklist b/test/rng_benchmark.tasklist
new file mode 100644
index 0000000000..19615b9ea8
--- /dev/null
+++ b/test/rng_benchmark.tasklist
@@ -0,0 +1,9 @@
+/* Copyright 2022 The ChromiumOS Authors
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+/**
+ * See CONFIG_TASK_LIST in config.h for details.
+ */
+#define CONFIG_TEST_TASK_LIST
\ No newline at end of file
diff --git a/test/run_device_tests.py b/test/run_device_tests.py
index 0b5a291b6c..fcf9a99651 100755
--- a/test/run_device_tests.py
+++ b/test/run_device_tests.py
@@ -257,6 +257,7 @@ class AllTests:
             TestConfig(test_name="pingpong"),
             TestConfig(test_name="printf"),
             TestConfig(test_name="queue"),
+            TestConfig(test_name="rng_benchmark"),
             TestConfig(
                 config_name="rollback_region0",
                 test_name="rollback",