Re: [PATCH V3 0/2] clk: imx: introduce fsl,always-on-clocks

From: Marco Felsch
Date: Tue Sep 13 2022 - 06:30:21 EST


Hi Peng,

On 22-09-13, Peng Fan (OSS) wrote:
> From: Peng Fan <peng.fan@xxxxxxx>
>
> V3:
> Rename to fsl,always-on-clocks
>
> V2:
> Use protected-clocks
> https://lore.kernel.org/all/20220816130327.2987710-1-peng.fan@xxxxxxxxxxx/
>
> V1:
> Use fsl,protected-clocks
> https://lore.kernel.org/all/20220815033632.1687854-1-peng.fan@xxxxxxxxxxx/
>
> There are two cases that I wanna this property could serve:
> Virtualization: root cell linux run in parallel with inmate cell
> AMP: M7/4 runs in parallel with A53
>
> The major case is:
> Jailhouse hypervisor only support partition, so devices are partitioned.
> But there is only CCM module that provides clock, the CCM is handled by
> root cell linux, need make sure the root cell linux not shutdown the
> clocks using by inmate cell.
>
> I was thinking whether need to provide a rate entry to ask root cell
> configure the clk rate for inmate cell. But NXP downstream not have it,
> see https://source.codeaurora.org/external/imx/linux-imx/tree/drivers/clk/imx/clk-imx8mp.c?h=lf-5.15.y#n690
> So just leave the property as uint32-array.

Can you please check my recent proposal? I recently stumbled over such
an issue on the mx8mm-evk as well but with the 32k clock provided by the
pmic. Unfortunately I forgot to add you to the to list, I will change
that. If that proposal will fix your problem, I would like to go the
generic way.

https://patchwork.kernel.org/project/linux-clk/list/?series=676522

Regards,
Marco


>
> This patchset could also benifit AMP case, check the two commits
> commit 19565ea12d61 ("clk: imx: add mcore_booted module paratemter")
> commit d097cc045b64 ("clk: imx8mp: remove SYS PLL 1/2 clock gates")
> Although I not plan to drop the upper two patches, this patchset
> exposes opportunity for better power consumption.
>
> Peng Fan (2):
> dt-bindings: clock: imx8m/imx93: introduce fsl,always-on-clocks
> property
> clk: imx: support fsl,always-on-clocks
>
> .../bindings/clock/imx8m-clock.yaml | 4 ++++
> .../bindings/clock/imx93-clock.yaml | 4 ++++
> drivers/clk/imx/clk-imx8mm.c | 2 ++
> drivers/clk/imx/clk-imx8mn.c | 2 ++
> drivers/clk/imx/clk-imx8mp.c | 2 ++
> drivers/clk/imx/clk-imx8mq.c | 2 ++
> drivers/clk/imx/clk.c | 21 +++++++++++++++++++
> drivers/clk/imx/clk.h | 2 ++
> 8 files changed, 39 insertions(+)
>
> --
> 2.37.1
>
>
>