Re: [PATCH] clk: add new Kconfig to control default behavior of disabling unused clocks

Maxime Ripard
2026-03-17T07:30:33Z

[-- Attachment #1: Type: text/plain, Size: 905 bytes --]

Hi,

On Mon, Mar 16, 2026 at 06:33:45PM -0400, Brian Masney wrote:
> At the 2023 Linux Plumbers Conference in Richmond VA, there was a
> discussion about how large number of systems need to boot with
> clk_ignore_unused. Per the discussions at the conference, the existing
> behavior in the clk core is broken, and there is a desire to completely
> remove this functionality.

Broken how?

clk_ignore_unused is to a point where it's seriously cargo-culted and
documented as a silver bullet, when in reality it's just a debug tool
for broken drivers, and the driver must be fixed.

But nobody is actually fixing it.

See
https://fedoraproject.org/wiki/Changes/Automatic_DTB_selection_for_aarch64_EFI_systems#How_To_Test
for example. The affected clock could be marked as CLK_IS_CRITICAL, and
fedora wouldn't have to package anything, change anything, etc. But no,
the problem is clk_ignore_unused.

Maxime

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 273 bytes --]