Re: [PATCH v2 3/3] clk: divider: test: Add tests for rates above 4.29 GHz

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential
issue to consider:
- [Low] clk: divider: test: unlocked clk_hw_round_rate() calls trigger
  lockdep warning
--

commit 25eaef0a68df414370fdc908fa118bc3dbfa005e
Author: Carlo Caione <ccaione@baylibre.com>

clk: divider: test: Add tests for rates above 4.29 GHz

This commit adds KUnit test suites for clk dividers covering rates above
4.29 GHz on 64-bit platforms and round-closest dividers requested above
their parent rate.

> diff --git a/drivers/clk/clk-divider_test.c b/drivers/clk/clk-divider_test.c
> index 8ee1614128d09..734cbdad55ddf 100644
> --- a/drivers/clk/clk-divider_test.c
> +++ b/drivers/clk/clk-divider_test.c

[ ... ]

> +static void clk_divider_large_rate_round_up(struct kunit *test)
> +{
> +	struct clk_hw *div_hw;
> +	u32 *fake_reg;
> +
> +	fake_reg = kunit_kzalloc(test, sizeof(*fake_reg), GFP_KERNEL);
> +	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, fake_reg);
> +
> +	div_hw = clk_divider_large_rate_init(test, fake_reg, PARENT_RATE_6GHZ,
> +					     0, 0);
> +
> +	KUNIT_EXPECT_EQ(test, clk_hw_round_rate(div_hw, PARENT_RATE_6GHZ),
> +			PARENT_RATE_6GHZ);
> +}

[Severity: Low]
Does calling clk_hw_round_rate() here (and in the other rounding test
cases below) trigger a lockdep warning when CONFIG_LOCKDEP is enabled?

clk_hw_round_rate() is a provider helper that expects prepare_lock to be
held and calls clk_core_init_rate_req() and clk_core_round_rate_nolock(),
which assert lockdep_assert_held(&prepare_lock).  Obtaining a struct clk
via clk_hw_get_clk_kunit() and calling clk_round_rate() instead would
acquire prepare_lock properly.

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20261112-upstream-clk-divider-large-rates-v2-0-18f3bb888b0c@baylibre.com?part=3