Re: [PATCH 2/2] dt-bindings: clock: intel,cgu-lgm: add mxl,control-gate option

[Florian Eckert]

Hello Krzysztof,

> > > You described the desired Linux feature or behavior, not the actual
> > > hardware. The bindings are about the latter, so instead you need to
> > > rephrase the property and its description to match actual hardware
> > > capabilities/features/configuration etc.
> >
> > You have correctly identified that this is not a hardware 
> > configuration,
> > but a driver configuration. Currently, the driver is configured so 
> > that
> > the gates cannot be switched via the clk subsystem callbacks. When
> > registering the data structures from the driver, I have to pass a flag
> > GATE_CLK_HW so that the gate is managed by the driver.
> >
> > I didn't want to always change the source of the driver when it has to
> > take
> > care of the GATE, so I wanted to map this via the dts.
> >
> > I have a board support package from Maxlinear for the Lightning 
> > Mountain
> > Soc
> > with other drivers that are not upstream now. Some of them use the
> > clock framework some of them does not.
> >
> > Due to missing documents it is not possible to send these drivers
> > upstream.
>
> So when you upstream them, the binding becomes wrong or not needed?
> Sorry, bindings are entirely independent of OS, so using this as an
> argument is clear no-go.

Yes, that would probably be the case, as the maxlinear drivers are at
an early stage and are not yet upstreamable in my opinion. If I had the
documents, I would take a closer look. But they are developing behind
closed doors. Nothing can be contributed. Not until the drivers are
hopefully upstream at some point as the cgu-lgm.

> > Strictly speaking, this is about the gptc and the watchdog.
> >
> > Since it is a buildin_platform driver, it can also not work via
> > module parameters.
>
> None of this explains any hardware related part of this binding. You
> created now policy for one specific OS. Devicetree, which is OS
> independent, is not for such purposes.

Yes this would be the case. Maybe I need to patch the cgu-lgm.c [1]
and send it upstream to restore the old behavior.
Because the following commit has changed the behaviour [2].
Unfortunately, it is also included in 5.15 stable branch.
Which in my opinion should not have happened!

Best regards,
Florian

[1] 
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/clk/x86/clk-lgm.c?h=v6.5-rc4
[2] 
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/drivers/clk/x86/clk-cgu.c?h=v5.15.123&id=a0583edea4fdb7b5b87a077263dddab476e9f138