Re: [PATCH 07/15] dt-bindings: clock: Add Ambarella clock bindings

Li Chen
2023-02-06T14:58:04Z

Hi Krzysztof,
---- On Mon, 06 Feb 2023 21:41:44 +0800 Krzysztof Kozlowski wrote ---
> On 06/02/2023 12:28, Li Chen wrote:
> > Hi Krzysztof ,
> >
> > ---- On Fri, 27 Jan 2023 23:08:09 +0800 Krzysztof Kozlowski wrote ---
> > > On 27/01/2023 15:48, Li Chen wrote:
> > > > >
> > > > > but what you are saying is that there is no separate clock controller
> > > > > device with its own IO address but these clocks are part of rct_syscon.
> > > > > Then model it that way in DTS. The rct_syscon is then your clock
> > > > > controller and all these fake gclk-core and gclk-ddr nodes should be gone.
> > > >
> > > > Ok, I will remove these fake nodes, and model the hardware as:
> > > >
> > > > rct_syscon node
> > > > | clock node(pll, div, mux, composite clocks live in the same driver)
> > > > | other periphal nodes
> > >
> > > You need clock node if it takes any resources. If it doesn't, you do not
> > > need it.
> >
> > If the only hardware resource the clock node can take is its parent clock(clocks = &osc;),
> > then can I have this clock node?
>
> I am not sure if I understand. osc does not look like parent device, so
> this part of comment confuses me.

Sorry for the confusion. I mean osc is the root of clock tree:

osc
| pll A
| pll B
| ...

So if I have a clock node under rct_syscon node, I think it should take osc as the parent(node) clock:
rct_syscon {
......
clock_controller {
clocks = <&osc>;
......

You have said "You need clock node if it takes any resources. ", do you think osc here can be counted as a used resource?

Regards,
Li