Re: [PATCH] ARM: dts: ti/omap: gta04: fix pm issues caused by spi module

[Andreas Kemnade <andreas@kemnade.info>]

Am Mon, 11 Nov 2024 17:09:53 +0200
schrieb Tony Lindgren <tony@atomide.com>:

> * Andreas Kemnade <andreas@kemnade.info> [241108 17:41]:
> > They are not used, if they are just disabled, kernel does not touch
> > them, so if it is there, the kernel can handle
> > pm. At least as long as it is not under ti,sysc.
> > 
> > There are probably cleaner solutions for this, but for a CC: stable I
> > would prefer something less invasive.  
> 
> For unused devices, it's best to configure things to use ti-sysc, and
> then set status disabled (or reserved) for the child devices only. This
> way the parent interconnect target module is PM runtime managed by
> Linux, and it's power domain gets properly idled for the unused devices
> too.
> 
Hmm, we also have omap_hwmod_setup_all() which is still called if
without device nodes being available.

Converting mcspi to ti-sysc is more than 100 lines. So it does not
qualify for stable.

> > I can try a ti-sysc based fix in parallel.  
> 
> Yeah that should be trivial hopefully :)
> 
I played around, got pm issues too, tried to force-enable things (via
power/control),
watched CM_IDLEST1_CORE and CM_FCLKEN1_CORE, they behave. Bits are set
or reset.

but not CM_IDLEST_CKGEN, it is 0x209 instead of 0x1.

I test from initramfs, so no mmc activity involved

removing status = "disabled" from mcspi3 solves things.
With and without ti-sysc conversion. removing status = "disabled" from
mcspi4 seems not to help.

That all cannot be... I will retry tomorrow.

Regards,
Andreas