Re: [PATCH v3 04/17] dt-bindings: soc: mobileye: add EyeQ5 OLB system controller

[Krzysztof Kozlowski]

On 25/01/2024 12:01, Théo Lebrun wrote:
> Hello,
> 
> On Thu Jan 25, 2024 at 8:51 AM CET, Krzysztof Kozlowski wrote:
>> On 24/01/2024 16:14, Rob Herring wrote:
>>>> +
>>>> +      pinctrl-b {
>>>> +        compatible = "mobileye,eyeq5-b-pinctrl";
>>>> +        #pinctrl-cells = <1>;
>>>> +      };
>>>> +    };
>>>
>>> This can all be simplified to:
>>>
>>> system-controller@e00000 {
>>>     compatible = "mobileye,eyeq5-olb", "syscon";
>>>     reg = <0xe00000 0x400>;
>>>     #reset-cells = <2>;
>>>     #clock-cells = <1>;
>>>     clocks = <&xtal>;
>>>     clock-names = "ref";
>>>
>>>     pins { ... };
>>> };
>>>
>>> There is no need for sub nodes unless you have reusable blocks or each 
>>> block has its own resources in DT.
>>
>> Yes, however I believe there should be resources here: each subnode
>> should get its address space. This is a bit tied to implementation,
>> which currently assumes "everyone can fiddle with everything" in this block.
>>
>> Theo, can you draw memory map?
> 
> It would be a mess. I've counted things up. The first 147 registers are
> used in this 0x400 block. There are 31 individual blocks, with 7
> registers unused (holes to align next block).

Holes are not really a problem.

> 
> Functions are reset, clocks, LBIST, MBIST, DDR control, GPIO,
> accelerator control, CPU entrypoint, PDTrace, IRQs, chip info & ID
> stuff, control registers for PCIe / eMMC / Eth / SGMII / DMA / etc.

So they are within separate blocks or not?



Best regards,
Krzysztof