Re: [PATCH v2 1/2] clk: ti: mux: resolve parent clocks by DT index, not by name

[Brian Masney <bmasney@redhat.com>]

Hi Stephen / Geert,

On Tue, Aug 18, 2026 at 06:02:56PM +0200, Geert Uytterhoeven wrote:
> On Mon, 27 Jul 2026 at 09:44, Mathieu Dubois-Briand
> <mathieu.dubois-briand@bootlin.com> wrote:
> > Resolve parent clocks by their index into the device tree "clocks"
> > property rather than matching names as strings. Name-based matching is
> > fragile because a clock's "clock-output-names" value in its provider
> > node can differ from the name used to reference it in a consumer node,
> > and because names must be globally unique across all clock providers.
> >
> > On AM335x, this caused broken clock trees where some clocks failed to
> > enable because their parents could not be found.
> >
> > Replace of_clk_parent_fill() with a clk_parent_data array that sets
> > .index to the array position.
> >
> > Fixes: ec7aa25fa483 ("ARM: dts: Use clock-output-names for am3")
> > Signed-off-by: Mathieu Dubois-Briand <mathieu.dubois-briand@bootlin.com>
> 
> Thanks for your patch, which is now commit 667f420c09f1417c ("clk: ti:
> mux: resolve parent clocks by DT index, not by name") in clk/clk-next.
> 
> This breaks booting BeagleBone Black for me: I don't get any output
> on the serial console, even with "earlycon keep_bootcon".  When the
> watchdog kicks in (or on kernel panic?), the system reboots.
> 
> Reverting this commit fixes the issue.
> After reverting, I added debug code to print all parents, and compared
> them to the DTB, but didn't see any discrepancies.
> 
> Your similar change to drivers/clk/ti/composite.c does not cause any
> issues for me.
> 
> Do you have a clue?

Stephen: I think the safest thing is to just drop / revert the two
patches in this series in the pull to Linus next week. I'd do it now,
however I'm still waiting for my kernel.org account to get created,
and don't have write access to the clk tree yet.

Mathieu: Feel free to post an updated version, and we can get it merged
earlier in the development cycle so it'll get more testing in next.
Hopefully Geert will have time to test an updated version.

Brian