clk: sunxi-ng: ccu_common: Use readl_relaxed_poll_timeout_atomic for PLL lock

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.

Switch to readl_relaxed_poll_timeout_atomic(). This atomic variant relies
on udelay() rather than timekeeping, making it safe to execute even when
timekeeping is suspended or uninitialized.

Assisted-by: LLM
Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
Link: https://patch.msgid.link/20260916042910.382744-1-alastair@d-silva.org
Signed-off-by: Chen-Yu Tsai <wens@kernel.org>

0 files changed, 0 insertions, 0 deletions