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mripardbebarino
mripard
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clk: tests: Add tests for notifiers
We're recently encountered a regression due to the rates reported through the clk_notifier_data being off when changing parents. Let's add a test suite and a test to make sure that we do get notified and with the proper rates. Suggested-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Maxime Ripard <maxime@cerno.tech> Link: https://lore.kernel.org/r/20221010-rpi-clk-fixes-again-v1-2-d87ba82ac404@cerno.tech Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Stephen Boyd <sboyd@kernel.org>
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‎drivers/clk/clk_test.c

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Original file line numberDiff line numberDiff line change
@@ -2239,10 +2239,166 @@ static struct kunit_suite clk_leaf_mux_set_rate_parent_test_suite = {
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.test_cases = clk_leaf_mux_set_rate_parent_test_cases,
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};
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struct clk_mux_notifier_rate_change {
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bool done;
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unsigned long old_rate;
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unsigned long new_rate;
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wait_queue_head_t wq;
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};
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struct clk_mux_notifier_ctx {
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struct clk_multiple_parent_ctx mux_ctx;
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struct clk *clk;
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struct notifier_block clk_nb;
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struct clk_mux_notifier_rate_change pre_rate_change;
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struct clk_mux_notifier_rate_change post_rate_change;
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};
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#define NOTIFIER_TIMEOUT_MS 100
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static int clk_mux_notifier_callback(struct notifier_block *nb,
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unsigned long action, void *data)
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{
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struct clk_notifier_data *clk_data = data;
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struct clk_mux_notifier_ctx *ctx = container_of(nb,
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struct clk_mux_notifier_ctx,
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clk_nb);
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if (action & PRE_RATE_CHANGE) {
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ctx->pre_rate_change.old_rate = clk_data->old_rate;
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ctx->pre_rate_change.new_rate = clk_data->new_rate;
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ctx->pre_rate_change.done = true;
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wake_up_interruptible(&ctx->pre_rate_change.wq);
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}
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if (action & POST_RATE_CHANGE) {
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ctx->post_rate_change.old_rate = clk_data->old_rate;
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ctx->post_rate_change.new_rate = clk_data->new_rate;
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ctx->post_rate_change.done = true;
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wake_up_interruptible(&ctx->post_rate_change.wq);
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}
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return 0;
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}
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static int clk_mux_notifier_test_init(struct kunit *test)
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{
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struct clk_mux_notifier_ctx *ctx;
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const char *top_parents[2] = { "parent-0", "parent-1" };
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int ret;
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ctx = kunit_kzalloc(test, sizeof(*ctx), GFP_KERNEL);
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if (!ctx)
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return -ENOMEM;
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test->priv = ctx;
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ctx->clk_nb.notifier_call = clk_mux_notifier_callback;
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init_waitqueue_head(&ctx->pre_rate_change.wq);
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init_waitqueue_head(&ctx->post_rate_change.wq);
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ctx->mux_ctx.parents_ctx[0].hw.init = CLK_HW_INIT_NO_PARENT("parent-0",
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&clk_dummy_rate_ops,
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0);
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ctx->mux_ctx.parents_ctx[0].rate = DUMMY_CLOCK_RATE_1;
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ret = clk_hw_register(NULL, &ctx->mux_ctx.parents_ctx[0].hw);
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if (ret)
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return ret;
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ctx->mux_ctx.parents_ctx[1].hw.init = CLK_HW_INIT_NO_PARENT("parent-1",
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&clk_dummy_rate_ops,
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0);
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ctx->mux_ctx.parents_ctx[1].rate = DUMMY_CLOCK_RATE_2;
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ret = clk_hw_register(NULL, &ctx->mux_ctx.parents_ctx[1].hw);
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if (ret)
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return ret;
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ctx->mux_ctx.current_parent = 0;
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ctx->mux_ctx.hw.init = CLK_HW_INIT_PARENTS("test-mux", top_parents,
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&clk_multiple_parents_mux_ops,
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0);
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ret = clk_hw_register(NULL, &ctx->mux_ctx.hw);
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if (ret)
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return ret;
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ctx->clk = clk_hw_get_clk(&ctx->mux_ctx.hw, NULL);
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ret = clk_notifier_register(ctx->clk, &ctx->clk_nb);
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if (ret)
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return ret;
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return 0;
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}
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static void clk_mux_notifier_test_exit(struct kunit *test)
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{
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struct clk_mux_notifier_ctx *ctx = test->priv;
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struct clk *clk = ctx->clk;
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clk_notifier_unregister(clk, &ctx->clk_nb);
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clk_put(clk);
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clk_hw_unregister(&ctx->mux_ctx.hw);
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clk_hw_unregister(&ctx->mux_ctx.parents_ctx[0].hw);
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clk_hw_unregister(&ctx->mux_ctx.parents_ctx[1].hw);
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}
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/*
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* Test that if the we have a notifier registered on a mux, the core
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* will notify us when we switch to another parent, and with the proper
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* old and new rates.
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*/
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static void clk_mux_notifier_set_parent_test(struct kunit *test)
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{
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struct clk_mux_notifier_ctx *ctx = test->priv;
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struct clk_hw *hw = &ctx->mux_ctx.hw;
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struct clk *clk = clk_hw_get_clk(hw, NULL);
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struct clk *new_parent = clk_hw_get_clk(&ctx->mux_ctx.parents_ctx[1].hw, NULL);
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int ret;
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ret = clk_set_parent(clk, new_parent);
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KUNIT_ASSERT_EQ(test, ret, 0);
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ret = wait_event_interruptible_timeout(ctx->pre_rate_change.wq,
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ctx->pre_rate_change.done,
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msecs_to_jiffies(NOTIFIER_TIMEOUT_MS));
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KUNIT_ASSERT_GT(test, ret, 0);
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KUNIT_EXPECT_EQ(test, ctx->pre_rate_change.old_rate, DUMMY_CLOCK_RATE_1);
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KUNIT_EXPECT_EQ(test, ctx->pre_rate_change.new_rate, DUMMY_CLOCK_RATE_2);
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ret = wait_event_interruptible_timeout(ctx->post_rate_change.wq,
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ctx->post_rate_change.done,
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msecs_to_jiffies(NOTIFIER_TIMEOUT_MS));
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KUNIT_ASSERT_GT(test, ret, 0);
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KUNIT_EXPECT_EQ(test, ctx->post_rate_change.old_rate, DUMMY_CLOCK_RATE_1);
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KUNIT_EXPECT_EQ(test, ctx->post_rate_change.new_rate, DUMMY_CLOCK_RATE_2);
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clk_put(new_parent);
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clk_put(clk);
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}
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static struct kunit_case clk_mux_notifier_test_cases[] = {
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KUNIT_CASE(clk_mux_notifier_set_parent_test),
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{}
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};
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/*
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* Test suite for a mux with multiple parents, and a notifier registered
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* on the mux.
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*
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* These tests exercise the behaviour of notifiers.
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*/
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static struct kunit_suite clk_mux_notifier_test_suite = {
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.name = "clk-mux-notifier",
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.init = clk_mux_notifier_test_init,
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.exit = clk_mux_notifier_test_exit,
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.test_cases = clk_mux_notifier_test_cases,
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};
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kunit_test_suites(
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&clk_leaf_mux_set_rate_parent_test_suite,
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&clk_test_suite,
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&clk_multiple_parents_mux_test_suite,
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&clk_mux_notifier_test_suite,
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&clk_orphan_transparent_multiple_parent_mux_test_suite,
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&clk_orphan_transparent_single_parent_test_suite,
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&clk_orphan_two_level_root_last_test_suite,

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