Re: [RFC PATCH 6/7] ARM: dts: stm32: add ETZPC as a system bus for STM32MP15x boards

[Gatien CHEVALLIER]

Hello,


On 12/22/22 11:30, Krzysztof Kozlowski wrote:
> On 21/12/2022 18:30, Gatien Chevallier wrote:
> > The STM32 System Bus is an internal bus on which devices are connected.
> > ETZPC is a peripheral overseeing the firewall bus that configures
> > and control access to the peripherals connected on it.
> >
> > For more information on which peripheral is securable, please read
> > the STM32MP15 reference manual.
> >
> > Signed-off-by: Gatien Chevallier <gatien.chevallier@xxxxxxxxxxx>
> > ---
> >   arch/arm/boot/dts/stm32mp151.dtsi | 2737 +++++++++++++++--------------
> >   1 file changed, 1406 insertions(+), 1331 deletions(-)
> >   
> > -		lptimer1: timer@40009000 {
> > +		etzpc: etzpc@5c007000 {
>
> Node names should be generic.
> https://devicetree-specification.readthedocs.io/en/latest/chapter2-devicetree-basics.html#generic-names-recommendation

Will change to etzpc: bus@5c007000 in V3

> > +			compatible = "st,stm32mp15-sys-bus";
> > +			reg = <0x5c007000 0x400>;
> >   			#address-cells = <1>;
> > -			#size-cells = <0>;
> > -			compatible = "st,stm32-lptimer";
> > -			reg = <0x40009000 0x400>;
> > -			interrupts-extended = <&exti 47 IRQ_TYPE_LEVEL_HIGH>;
> > -			clocks = <&rcc LPTIM1_K>;
> > -			clock-names = "mux";
> > -			wakeup-source;
> > -			status = "disabled";
>
> Why entire bus is disabled? What resources do you miss?

Here, I did not want to modify the status of the nodes in the device 
tree. Nodes that are default enabled in the SoC device tree stay enabled 
and vice-versa. IMO think this patch should not include these kind of 
changes in its scope. I describe the bus and the peripherals connected 
to it, nothing more :)

> > +			#size-cells = <1>;
> > +			feature-domain-controller;
> > +			#feature-domain-cells = <2>;
> > +			ranges;
> >   
> Best regards,
> Krzysztof

Best regards,
Gatien