1 files changed, 92 insertions, 1 deletions

diff --git a/drivers/clk/clk_test.c b/drivers/clk/clk_test.c
index b8e32406a6e4..b269420dafcc 100644
--- a/drivers/clk/clk_test.c
+++ b/drivers/clk/clk_test.c
@@ -270,6 +270,96 @@ static struct kunit_suite clk_test_suite = {
 	.test_cases = clk_test_cases,
 };
 
+static int clk_uncached_test_init(struct kunit *test)
+{
+	struct clk_dummy_context *ctx;
+	int ret;
+
+	ctx = kunit_kzalloc(test, sizeof(*ctx), GFP_KERNEL);
+	if (!ctx)
+		return -ENOMEM;
+	test->priv = ctx;
+
+	ctx->rate = DUMMY_CLOCK_INIT_RATE;
+	ctx->hw.init = CLK_HW_INIT_NO_PARENT("test-clk",
+					     &clk_dummy_rate_ops,
+					     CLK_GET_RATE_NOCACHE);
+
+	ret = clk_hw_register(NULL, &ctx->hw);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+/*
+ * Test that for an uncached clock, the clock framework doesn't cache
+ * the rate and clk_get_rate() will return the underlying clock rate
+ * even if it changed.
+ */
+static void clk_test_uncached_get_rate(struct kunit *test)
+{
+	struct clk_dummy_context *ctx = test->priv;
+	struct clk_hw *hw = &ctx->hw;
+	struct clk *clk = clk_hw_get_clk(hw, NULL);
+	unsigned long rate;
+
+	rate = clk_get_rate(clk);
+	KUNIT_ASSERT_GT(test, rate, 0);
+	KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_INIT_RATE);
+
+	/* We change the rate behind the clock framework's back */
+	ctx->rate = DUMMY_CLOCK_RATE_1;
+	rate = clk_get_rate(clk);
+	KUNIT_ASSERT_GT(test, rate, 0);
+	KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_1);
+
+	clk_put(clk);
+}
+
+/*
+ * Test that for an uncached clock, clk_set_rate_range() will work
+ * properly if the rate hasn't changed.
+ */
+static void clk_test_uncached_set_range(struct kunit *test)
+{
+	struct clk_dummy_context *ctx = test->priv;
+	struct clk_hw *hw = &ctx->hw;
+	struct clk *clk = clk_hw_get_clk(hw, NULL);
+	unsigned long rate;
+
+	KUNIT_ASSERT_EQ(test,
+			clk_set_rate_range(clk,
+					   DUMMY_CLOCK_RATE_1,
+					   DUMMY_CLOCK_RATE_2),
+			0);
+
+	rate = clk_get_rate(clk);
+	KUNIT_ASSERT_GT(test, rate, 0);
+	KUNIT_EXPECT_GE(test, rate, DUMMY_CLOCK_RATE_1);
+	KUNIT_EXPECT_LE(test, rate, DUMMY_CLOCK_RATE_2);
+
+	clk_put(clk);
+}
+
+static struct kunit_case clk_uncached_test_cases[] = {
+	KUNIT_CASE(clk_test_uncached_get_rate),
+	KUNIT_CASE(clk_test_uncached_set_range),
+	{}
+};
+
+/*
+ * Test suite for a basic, uncached, rate clock, without any parent.
+ *
+ * These tests exercise the rate API with simple scenarios
+ */
+static struct kunit_suite clk_uncached_test_suite = {
+	.name = "clk-uncached-test",
+	.init = clk_uncached_test_init,
+	.exit = clk_test_exit,
+	.test_cases = clk_uncached_test_cases,
+};
+
 struct clk_single_parent_ctx {
 	struct clk_dummy_context parent_ctx;
 	struct clk_hw hw;
@@ -1077,6 +1167,7 @@ kunit_test_suites(
 	&clk_orphan_transparent_single_parent_test_suite,
 	&clk_range_test_suite,
 	&clk_range_maximize_test_suite,
-	&clk_range_minimize_test_suite
+	&clk_range_minimize_test_suite,
+	&clk_uncached_test_suite
 );
 MODULE_LICENSE("GPL v2");