From 589a2004881f0941ca46146a5de68b3666d1d54a Mon Sep 17 00:00:00 2001 From: Maxime Ripard Date: Mon, 10 Oct 2022 16:47:39 +0200 Subject: 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 Signed-off-by: Maxime Ripard Link: https://lore.kernel.org/r/20221010-rpi-clk-fixes-again-v1-2-d87ba82ac404@cerno.tech Tested-by: Marek Szyprowski Signed-off-by: Stephen Boyd --- drivers/clk/clk_test.c | 156 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 156 insertions(+) (limited to 'drivers/clk/clk_test.c') diff --git a/drivers/clk/clk_test.c b/drivers/clk/clk_test.c index 509256c5567a..f9a5c2964c65 100644 --- a/drivers/clk/clk_test.c +++ b/drivers/clk/clk_test.c @@ -2239,10 +2239,166 @@ static struct kunit_suite clk_leaf_mux_set_rate_parent_test_suite = { .test_cases = clk_leaf_mux_set_rate_parent_test_cases, }; +struct clk_mux_notifier_rate_change { + bool done; + unsigned long old_rate; + unsigned long new_rate; + wait_queue_head_t wq; +}; + +struct clk_mux_notifier_ctx { + struct clk_multiple_parent_ctx mux_ctx; + struct clk *clk; + struct notifier_block clk_nb; + struct clk_mux_notifier_rate_change pre_rate_change; + struct clk_mux_notifier_rate_change post_rate_change; +}; + +#define NOTIFIER_TIMEOUT_MS 100 + +static int clk_mux_notifier_callback(struct notifier_block *nb, + unsigned long action, void *data) +{ + struct clk_notifier_data *clk_data = data; + struct clk_mux_notifier_ctx *ctx = container_of(nb, + struct clk_mux_notifier_ctx, + clk_nb); + + if (action & PRE_RATE_CHANGE) { + ctx->pre_rate_change.old_rate = clk_data->old_rate; + ctx->pre_rate_change.new_rate = clk_data->new_rate; + ctx->pre_rate_change.done = true; + wake_up_interruptible(&ctx->pre_rate_change.wq); + } + + if (action & POST_RATE_CHANGE) { + ctx->post_rate_change.old_rate = clk_data->old_rate; + ctx->post_rate_change.new_rate = clk_data->new_rate; + ctx->post_rate_change.done = true; + wake_up_interruptible(&ctx->post_rate_change.wq); + } + + return 0; +} + +static int clk_mux_notifier_test_init(struct kunit *test) +{ + struct clk_mux_notifier_ctx *ctx; + const char *top_parents[2] = { "parent-0", "parent-1" }; + int ret; + + ctx = kunit_kzalloc(test, sizeof(*ctx), GFP_KERNEL); + if (!ctx) + return -ENOMEM; + test->priv = ctx; + ctx->clk_nb.notifier_call = clk_mux_notifier_callback; + init_waitqueue_head(&ctx->pre_rate_change.wq); + init_waitqueue_head(&ctx->post_rate_change.wq); + + ctx->mux_ctx.parents_ctx[0].hw.init = CLK_HW_INIT_NO_PARENT("parent-0", + &clk_dummy_rate_ops, + 0); + ctx->mux_ctx.parents_ctx[0].rate = DUMMY_CLOCK_RATE_1; + ret = clk_hw_register(NULL, &ctx->mux_ctx.parents_ctx[0].hw); + if (ret) + return ret; + + ctx->mux_ctx.parents_ctx[1].hw.init = CLK_HW_INIT_NO_PARENT("parent-1", + &clk_dummy_rate_ops, + 0); + ctx->mux_ctx.parents_ctx[1].rate = DUMMY_CLOCK_RATE_2; + ret = clk_hw_register(NULL, &ctx->mux_ctx.parents_ctx[1].hw); + if (ret) + return ret; + + ctx->mux_ctx.current_parent = 0; + ctx->mux_ctx.hw.init = CLK_HW_INIT_PARENTS("test-mux", top_parents, + &clk_multiple_parents_mux_ops, + 0); + ret = clk_hw_register(NULL, &ctx->mux_ctx.hw); + if (ret) + return ret; + + ctx->clk = clk_hw_get_clk(&ctx->mux_ctx.hw, NULL); + ret = clk_notifier_register(ctx->clk, &ctx->clk_nb); + if (ret) + return ret; + + return 0; +} + +static void clk_mux_notifier_test_exit(struct kunit *test) +{ + struct clk_mux_notifier_ctx *ctx = test->priv; + struct clk *clk = ctx->clk; + + clk_notifier_unregister(clk, &ctx->clk_nb); + clk_put(clk); + + clk_hw_unregister(&ctx->mux_ctx.hw); + clk_hw_unregister(&ctx->mux_ctx.parents_ctx[0].hw); + clk_hw_unregister(&ctx->mux_ctx.parents_ctx[1].hw); +} + +/* + * Test that if the we have a notifier registered on a mux, the core + * will notify us when we switch to another parent, and with the proper + * old and new rates. + */ +static void clk_mux_notifier_set_parent_test(struct kunit *test) +{ + struct clk_mux_notifier_ctx *ctx = test->priv; + struct clk_hw *hw = &ctx->mux_ctx.hw; + struct clk *clk = clk_hw_get_clk(hw, NULL); + struct clk *new_parent = clk_hw_get_clk(&ctx->mux_ctx.parents_ctx[1].hw, NULL); + int ret; + + ret = clk_set_parent(clk, new_parent); + KUNIT_ASSERT_EQ(test, ret, 0); + + ret = wait_event_interruptible_timeout(ctx->pre_rate_change.wq, + ctx->pre_rate_change.done, + msecs_to_jiffies(NOTIFIER_TIMEOUT_MS)); + KUNIT_ASSERT_GT(test, ret, 0); + + KUNIT_EXPECT_EQ(test, ctx->pre_rate_change.old_rate, DUMMY_CLOCK_RATE_1); + KUNIT_EXPECT_EQ(test, ctx->pre_rate_change.new_rate, DUMMY_CLOCK_RATE_2); + + ret = wait_event_interruptible_timeout(ctx->post_rate_change.wq, + ctx->post_rate_change.done, + msecs_to_jiffies(NOTIFIER_TIMEOUT_MS)); + KUNIT_ASSERT_GT(test, ret, 0); + + KUNIT_EXPECT_EQ(test, ctx->post_rate_change.old_rate, DUMMY_CLOCK_RATE_1); + KUNIT_EXPECT_EQ(test, ctx->post_rate_change.new_rate, DUMMY_CLOCK_RATE_2); + + clk_put(new_parent); + clk_put(clk); +} + +static struct kunit_case clk_mux_notifier_test_cases[] = { + KUNIT_CASE(clk_mux_notifier_set_parent_test), + {} +}; + +/* + * Test suite for a mux with multiple parents, and a notifier registered + * on the mux. + * + * These tests exercise the behaviour of notifiers. + */ +static struct kunit_suite clk_mux_notifier_test_suite = { + .name = "clk-mux-notifier", + .init = clk_mux_notifier_test_init, + .exit = clk_mux_notifier_test_exit, + .test_cases = clk_mux_notifier_test_cases, +}; + kunit_test_suites( &clk_leaf_mux_set_rate_parent_test_suite, &clk_test_suite, &clk_multiple_parents_mux_test_suite, + &clk_mux_notifier_test_suite, &clk_orphan_transparent_multiple_parent_mux_test_suite, &clk_orphan_transparent_single_parent_test_suite, &clk_orphan_two_level_root_last_test_suite, -- cgit v1.2.3