[PATCH 1/3] Documentation: Update the APM X-Gene SoC EDAC DTS binding for missing RB

[Loc Ho]

Hi Arnd,

>> --- a/Documentation/devicetree/bindings/edac/apm-xgene-edac.txt
>> +++ b/Documentation/devicetree/bindings/edac/apm-xgene-edac.txt
>> @@ -16,6 +16,7 @@ Required properties:
>>  - regmap-mcba          : Regmap of the MCB-A (memory bridge) resource.
>>  - regmap-mcbb          : Regmap of the MCB-B (memory bridge) resource.
>>  - regmap-efuse         : Regmap of the PMD efuse resource.
>> +- regmap-rb            : Regmap of the register bus resource.
>>  - reg                  : First resource shall be the CPU bus (PCP) resource.
>>  - interrupts            : Interrupt-specifier for MCU, PMD, L3, or SoC error
>>                           IRQ(s).
>> @@ -64,6 +65,11 @@ Example:
>>                 reg = <0x0 0x1054a000 0x0 0x20>;
>>         };
>>
>> +       rb: rb at 7e000000 {
>> +               compatible = "apm,xgene-rb", "syscon";
>> +               reg = <0x0 0x7e000000 0x0 0x10>;
>> +       };
>> +
>>         edac at 78800000 {
>>                 compatible = "apm,xgene-edac";
>>
>
> When you add a property, please list that as "optional", not "required",
> to ensure that the old dtb files still conform to the binding.
>
> In the driver, make sure it is not a fatal error when the property is
> missing and the driver can keep working without it.

>From my view, this is required. Otherwise, the error condition will
NOT be cleared correctly and will get constant interrupt. Though, for
compatibility, we can make it optional but system will be unusable
should such error occurred. Though, it would be rare or with bad FW. I
will fix in the next version by making it optional such as it will
still probe correctly with older DT binding.

-Loc