(subset) [PATCH 0/4] arm64: amlogic: t7: describe the VIM4 supplies and keep the fabric clocks running

[Lucas Tanure]

On Mon, Aug 31, 2026 at 1:44 PM Neil Armstrong
<neil.armstrong at linaro.org> wrote:
>
> Hi,
>
> On Sat, 29 Aug 2026 10:47:54 +0100, Lucas Tanure wrote:
> > The Khadas VIM4 has needed clk_ignore_unused to boot reliably. Without it
> > the board hangs at random, loses storage and corrupts memory, and the
> > failures move around from boot to boot.
> >
> > Six of the SoC's PWM outputs drive the board's voltage regulators: the
> > always-on domain, both CPU clusters, the GPU, the NPU and the DRAM. None
> > of them were described, so Linux saw the outputs as unused and switched
> > them off about a second into boot. The regulators then drifted away from
> > the levels the bootloader had set, which is where the corruption and the
> > random hangs came from.
> > Thanks to Chuan Liu from Amlogic for helping me indetify which clocks are
> > critical.
> >
> > [...]
>
> Thanks, Applied to https://git.kernel.org/pub/scm/linux/kernel/git/amlogic/linux.git (v7.3/fixes)
>
> [2/4] arm64: dts: amlogic: t7: fix the pin groups of two PWM outputs
>       https://git.kernel.org/amlogic/c/ae7be5c58a819259e5eb98a3abfa60842478f2ae
> [3/4] arm64: dts: amlogic: t7: khadas-vim4: add the PWM-driven supplies
>       https://git.kernel.org/amlogic/c/1e5a53bd16ac501e68463e84023d1bff543cc696
> [4/4] arm64: dts: amlogic: t7: fix the pin groups of the vsync PWM
>       https://git.kernel.org/amlogic/c/406292fd75f95aa3010fec95b5beb5a8b7e3ba3a
>
> These changes has been applied on the intermediate git tree [1].
>
> The v7.3/fixes branch will then be sent via a formal Pull Request to the Linux SoC maintainers
> for inclusion in their intermediate git branches in order to be sent to Linus during
> the next merge window, or sooner if it's a set of fixes.
>
> In the cases of fixes, those will be merged in the current release candidate
> kernel and as soon they appear on the Linux master branch they will be
> backported to the previous Stable and Long-Stable kernels [2].
>
> The intermediate git branches are merged daily in the linux-next tree [3],
> people are encouraged testing these pre-release kernels and report issues on the
> relevant mailing-lists.
>
> If problems are discovered on those changes, please submit a signed-off-by revert
> patch followed by a corrective changeset.
>
> [1] https://git.kernel.org/pub/scm/linux/kernel/git/amlogic/linux.git
> [2] https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
> [3] https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git
>
> --
> Neil
>
Hi,
Please don't take this. I will submit a better version.
sys_ampipe_nand should not be critical.

Thanks,
Lucas