zephyr: shim in hooks and deferred

Implement deferred calls using the Zephyr's delayed work queues.

Implement hooks using SYS_INIT and a hooks registry created during
init.

BUG=b:168030971
BRANCH=none
TEST=provided unit tests

     Build instructions for unit tests:
     zmake configure -B/tmp/test \
         ~/trunk/src/platform/ec/zephyr/test/hooks
     zmake build /tmp/test

Signed-off-by: Jack Rosenthal <jrosenth@chromium.org>
Change-Id: Id019cd1fe7bb3354377773d171036767e7efa706
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/2504489
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Jett Rink <jettrink@chromium.org>

4 files changed, 163 insertions, 0 deletions

diff --git a/zephyr/test/hooks/CMakeLists.txt b/zephyr/test/hooks/CMakeLists.txt
new file mode 100644
index 0000000000..9c6f0058fe
--- /dev/null
+++ b/zephyr/test/hooks/CMakeLists.txt
@@ -0,0 +1,9 @@
+# Copyright 2020 The Chromium OS Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+cmake_minimum_required(VERSION 3.13.1)
+project(hooks)
+find_package(Zephyr REQUIRED HINTS $ENV{ZEPHYR_BASE})
+
+target_sources(app PRIVATE hooks.c)
diff --git a/zephyr/test/hooks/hooks.c b/zephyr/test/hooks/hooks.c
new file mode 100644
index 0000000000..6b482b30cf
--- /dev/null
+++ b/zephyr/test/hooks/hooks.c
@@ -0,0 +1,134 @@
+/* Copyright 2020 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include <stdbool.h>
+#include <ztest.h>
+
+#include "hooks.h"
+
+static bool h1_called;
+static bool h2_called;
+static bool h3_called;
+
+static void h1(void)
+{
+	zassert_false(h1_called, "h1 was called, but should not have been");
+	zassert_false(h2_called, "h2 was called, but should not have been");
+	zassert_false(h3_called, "h3 was called, but should not have been");
+	h1_called = true;
+}
+DECLARE_HOOK(HOOK_TEST_1, h1, HOOK_PRIO_FIRST);
+
+static void h2(void)
+{
+	zassert_true(h1_called, "h1 was not called, but should have been");
+	zassert_false(h2_called, "h2 was called, but should not have been");
+	zassert_false(h3_called, "h3 was called, but should not have been");
+	h2_called = true;
+}
+DECLARE_HOOK(HOOK_TEST_1, h2, HOOK_PRIO_DEFAULT);
+
+static void h3(void)
+{
+	zassert_true(h1_called, "h1 was not called, but should have been");
+	zassert_true(h2_called, "h2 was not called, but should have been");
+	zassert_false(h3_called, "h3 was called, but should not have been");
+	h3_called = true;
+}
+DECLARE_HOOK(HOOK_TEST_1, h3, HOOK_PRIO_LAST);
+
+static void test_hook_list_multiple(void)
+{
+	hook_notify(HOOK_TEST_1);
+	zassert_true(h1_called, "h1 was not called, but should have been");
+	zassert_true(h2_called, "h2 was not called, but should have been");
+	zassert_true(h3_called, "h3 was not called, but should have been");
+}
+
+static bool h4_called;
+
+static void h4(void)
+{
+	zassert_false(h4_called, "h4 was called, but should not have been");
+	h4_called = true;
+}
+DECLARE_HOOK(HOOK_TEST_2, h4, HOOK_PRIO_DEFAULT);
+
+static void test_hook_list_single(void)
+{
+	hook_notify(HOOK_TEST_2);
+	zassert_true(h4_called, "h4 was not called, but should have been");
+}
+
+static void test_hook_list_empty(void)
+{
+	hook_notify(HOOK_TEST_3);
+}
+
+static bool deferred_func_called;
+
+#define DEFERRED_DELAY_US (250 * 1000)
+static void deferred_func(void)
+{
+	deferred_func_called = true;
+}
+DECLARE_DEFERRED(deferred_func);
+
+static void test_deferred_func(void)
+{
+	zassert_false(
+		deferred_func_called,
+		"The deferred function was called, but should not have been");
+	hook_call_deferred(&deferred_func_data, DEFERRED_DELAY_US);
+	zassert_false(
+		deferred_func_called,
+		"The deferred function was called, but should not have been");
+	k_usleep(DEFERRED_DELAY_US * 2);
+	zassert_true(
+		deferred_func_called,
+		"The deferred function was not called, but should have been");
+}
+
+static bool deferred_func_2_called;
+
+static void deferred_func_2(void)
+{
+	deferred_func_2_called = true;
+}
+DECLARE_DEFERRED(deferred_func_2);
+
+/*
+ * Test that repeated calls to hook_call_deferred result in the
+ * function being pushed out.
+ */
+static void test_deferred_func_push_out(void)
+{
+	zassert_false(
+		deferred_func_2_called,
+		"The deferred function was called, but should not have been");
+	hook_call_deferred(&deferred_func_2_data, DEFERRED_DELAY_US);
+	hook_call_deferred(&deferred_func_2_data, DEFERRED_DELAY_US * 3);
+	k_usleep(DEFERRED_DELAY_US * 2);
+	zassert_false(
+		deferred_func_2_called,
+		"The deferred function was called, but should not have been");
+	k_usleep(DEFERRED_DELAY_US * 2);
+	zassert_true(
+		deferred_func_called,
+		"The deferred function was not called, but should have been");
+}
+
+void test_main(void)
+{
+	ztest_test_suite(
+		hooks_tests,
+		ztest_unit_test(test_hook_list_multiple),
+		ztest_unit_test(test_hook_list_single),
+		ztest_unit_test(test_hook_list_empty),
+		ztest_unit_test(test_deferred_func),
+		ztest_unit_test(test_deferred_func_push_out));
+
+	ztest_run_test_suite(hooks_tests);
+}
diff --git a/zephyr/test/hooks/prj.conf b/zephyr/test/hooks/prj.conf
new file mode 100644
index 0000000000..43c0c9b8e5
--- /dev/null
+++ b/zephyr/test/hooks/prj.conf
@@ -0,0 +1,11 @@
+# Copyright 2020 The Chromium OS Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+CONFIG_ZTEST=y
+CONFIG_PLATFORM_EC=y
+
+# TODO(b/172512307): timer introduces dependency on system module,
+# which has build issues right now for native_posix board.  Remove
+# this once the system module has been corrected.
+CONFIG_PLATFORM_EC_TIMER=n
diff --git a/zephyr/test/hooks/zmake.yaml b/zephyr/test/hooks/zmake.yaml
new file mode 100644
index 0000000000..c784549bb0
--- /dev/null
+++ b/zephyr/test/hooks/zmake.yaml
@@ -0,0 +1,9 @@
+# Copyright 2020 The Chromium OS Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+board: native_posix
+supported-zephyr-versions:
+  - v2.4
+toolchain: zephyr
+output-type: elf