The call to clk_core_enable_lock done by __clk_core_init after checking
the clock flags for CLK_IS_CRITICAL enables the parent clock.

In Commit 669917676e93 ("clk: Respect CLK_OPS_PARENT_ENABLE during
recalc"), the parent gets disabled before this check, if the flag
CLK_OPS_PARENT_ENABLED is set on the clock. This results in a situation
where critical clocks have their parent briefly disabled, which kills
the system.

Fix this by moving the balancing operation to after the CLK_IS_CRITICAL
check, which should resolve the problem.

Fixes: 669917676e93 ("clk: Respect CLK_OPS_PARENT_ENABLE during recalc")
Reported-by: Mark Brown <broonie@kernel.org>
Closes: https://lore.kernel.org/r/036da7ce-6487-4a6e-9b15-97c6d3bcdcec@sirena.org.uk/
Signed-off-by: Nicolas Frattaroli <nicolas.frattaroli@collabora.com>
---
 drivers/clk/clk.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index 1b0f9d567f48..8f5ef9ce77d2 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -4056,9 +4056,6 @@ static int __clk_core_init(struct clk_core *core)
 		rate = 0;
 	core->rate = core->req_rate = rate;
 
-	if (core->flags & CLK_OPS_PARENT_ENABLE)
-		clk_core_disable_unprepare(core->parent);
-
 	/*
 	 * Enable CLK_IS_CRITICAL clocks so newly added critical clocks
 	 * don't get accidentally disabled when walking the orphan tree and
@@ -4081,6 +4078,9 @@ static int __clk_core_init(struct clk_core *core)
 		}
 	}
 
+	if (core->flags & CLK_OPS_PARENT_ENABLE)
+		clk_core_disable_unprepare(core->parent);
+
 	clk_core_reparent_orphans_nolock();
 out:
 	clk_pm_runtime_put(core);

-- 
2.52.0

On Wed, Jan 28, 2026 at 8:39 PM Nicolas Frattaroli
<nicolas.frattaroli@collabora.com> wrote:
>
> The call to clk_core_enable_lock done by __clk_core_init after checking
> the clock flags for CLK_IS_CRITICAL enables the parent clock.
>
> In Commit 669917676e93 ("clk: Respect CLK_OPS_PARENT_ENABLE during
> recalc"), the parent gets disabled before this check, if the flag
> CLK_OPS_PARENT_ENABLED is set on the clock. This results in a situation
> where critical clocks have their parent briefly disabled, which kills
> the system.
>
> Fix this by moving the balancing operation to after the CLK_IS_CRITICAL
> check, which should resolve the problem.
>
> Fixes: 669917676e93 ("clk: Respect CLK_OPS_PARENT_ENABLE during recalc")
> Reported-by: Mark Brown <broonie@kernel.org>
> Closes: https://lore.kernel.org/r/036da7ce-6487-4a6e-9b15-97c6d3bcdcec@sirena.org.uk/
> Signed-off-by: Nicolas Frattaroli <nicolas.frattaroli@collabora.com>

Hi Nicolas,

Would you consider please reverting faulty patch above as i.MX8mp is
still broken?

On Tue, Feb 03, 2026 at 12:13:22PM +0200, Daniel Baluta wrote:

> Would you consider please reverting faulty patch above as i.MX8mp is
> still broken?

Stephen posted a revert yesterday:

   https://lore.kernel.org/r/20260203002439.1223213-1-sboyd@kernel.org