[PATCH] ARM: dts: BCM5301X: Specify MDIO bus in the DT

Rafał Miłecki rafal at milecki.pl
Sun Apr 2 14:25:09 PDT 2017


On 04/02/2017 11:14 PM, Florian Fainelli wrote:
> Le 04/02/17 à 14:08, Rafał Miłecki a écrit :
>> From: Rafał Miłecki <rafal at milecki.pl>
>>
>> Northstar devices have MDIO bus that may contain various PHYs attached.
>> A common example is USB 3.0 PHY (that doesn't have an MDIO driver yet).
>>
>> Signed-off-by: Rafał Miłecki <rafal at milecki.pl>
>> ---
>>  arch/arm/boot/dts/bcm5301x.dtsi | 7 +++++++
>>  1 file changed, 7 insertions(+)
>>
>> diff --git a/arch/arm/boot/dts/bcm5301x.dtsi b/arch/arm/boot/dts/bcm5301x.dtsi
>> index acee36a61004..6a2afe7880ae 100644
>> --- a/arch/arm/boot/dts/bcm5301x.dtsi
>> +++ b/arch/arm/boot/dts/bcm5301x.dtsi
>> @@ -320,6 +320,13 @@
>>  		};
>>  	};
>>
>> +	mdio at 18003000 {
>> +		compatible = "brcm,iproc-mdio";
>> +		reg = <0x18003000 0x8>;
>> +		#size-cells = <1>;
>> +		#address-cells = <0>;
>> +	};
>
> This looks fine, but usually the block should be enabled on a per-board
> basis, such that there should be a status = "disabled" property here by
> default.

I think we have few blocks in bcm5301x.dtsi enabled by default. I guess it's
for stuff that is always present on every SoC family board: rng, nand, spi to
name few.

It makes some sense, consider e.g. spi. Every Northstar board has SPI
controller so it's enabled by default. Not every board has SPI flash, so it's
disabled by default.

It's there and it make sense to me. Is that OK or not?

I find MDIO situation quite simiar. It seems every Northstar board has MDIO bus
just devices may differ and should not be enabled by default.



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