Re: [PATCH v2] clk: sunxi-ng: ccu_common: Use readl_relaxed_poll_timeout_atomic for PLL lock

[Chen-Yu Tsai]

On Wed, 16 Sep 2026 14:29:10 +1000, Alastair D'Silva wrote:
> The Allwinner sunxi-ng CCU driver currently uses
> readl_relaxed_poll_timeout() in ccu_helper_wait_for_lock() to wait for
> PLLs to lock.
> 
> This non-atomic poll macro relies on ktime_get() and the kernel
> timekeeping infrastructure. During early boot or sensitive clock
> transitions (such as CPUfreq DVFS scaling) where timer interrupts or
> timekeeping may be suspended or unstable, ktime_get() fails to advance.
> This turns the timeout calculation into an infinite busy-wait loop,
> causing RCU stalls and system freezes if the PLL lock bit does not
> assert immediately.
> 
> [...]

Applied to sunxi/clk-for-7.4 in sunxi, thanks!

[1/1] clk: sunxi-ng: ccu_common: Use readl_relaxed_poll_timeout_atomic for PLL lock
      https://git.kernel.org/sunxi/linux/c/9ef62592b80c

Best regards,
-- 
Chen-Yu Tsai <wens@xxxxxxxxxx>