Re: ARM iMX6sx board fails to boot with kernel 6.17

From: Fabio Estevam
Date: Thu Oct 09 2025 - 11:51:19 EST


Hi Sergey,

On Thu, Oct 9, 2025 at 11:46 AM Sergey Organov <sorganov@xxxxxxxxx> wrote:

> > I tried booting 6.17 on an imx6sx-sdb board and it booted
> > successfully:
>
> Now after further investigations of the issue I find that success
> a bit surprising.
>
> I've found that my problem is cured by a commit in
>
> https://github.com/nxp-imx/linux-imx
>
> that works-around an issue that looks like imx6sx generic problem, and
> should probably cause troubles on imx6sx-sdb board as well, but doesn't?
> The commit is:
>
> commit 65cf3a49ab15cdbbede3c97fd6bba731a3cd366f
> Author: Anson Huang <b20788@xxxxxxxxxxxxx>
> AuthorDate: Tue Aug 18 15:53:54 2015 +0800
> Commit: Octavian Purdila <octavian.purdila@xxxxxxx>
> CommitDate: Thu Feb 23 14:21:42 2017 +0200
>
> MLK-11375-2 ARM: imx: disable cpuidle for imx6sx
>
> i.MX6SX CPUIdle with ARM core power down has issue
> and cause system hang during kernel boot up, disable
> it for now and will enable it when busfreq driver
> is ready.
>
> Later (by the DAG, not by date) on the same imx_4.9.11_1.0.0_ga
> branch at that repo, there is:
>
> commit 816978f83b1d8dd6ce3bd5dd62223dbfdf74bdd3
> Author: Anson Huang <b20788@xxxxxxxxxxxxx>
> AuthorDate: Mon Oct 20 16:16:20 2014 +0800
> Commit: Octavian Purdila <octavian.purdila@xxxxxxx>
> CommitDate: Thu Feb 23 14:21:42 2017 +0200
>
> MLK-9708 arm: imx: add low power idle support for i.mx6sx
>
> that effectively reverts the aforementioned commit while adding a lot of
> other stuff. The resulting kernel also boots fine on my hardware.
>
> Curiously enough, neither of these commits are there in the latest
> branch lf-6.12.y there (and that kernel hangs on my board as well.)
>
> Provided the latter commit is indeed the right fix for imx6sx support in
> the kernel, what's the procedure to get it to the mainstream Linux
> kernel?

It seems that your observation matches what Angelo (added on Cc)
reported a long time ago:

https://community.nxp.com/t5/i-MX-Processors/imx6sx-kernel-hangs-at-rootfs-mount/td-p/964920

I'd like to know if the bootloader version plays a role in the
different behavior that we see on the imx6sx-sdb versus your board.

I used U-Boot 2024.07 on my imx6sx-sdb. Which version did you use? Is
it based on an old NXP U-Boot tree?

Does using a recent bootloader make the hang disappear?