Re: [PATCH net-next v7 5/5] ARM: dts: qcom: ipq4019: Add description for the IPQESS Ethernet controller

[Vladimir Oltean]

On Fri, Nov 04, 2022 at 11:08:07AM -0400, Krzysztof Kozlowski wrote:
> On 04/11/2022 10:32, Vladimir Oltean wrote:
> > On Fri, Nov 04, 2022 at 10:31:06AM -0400, Krzysztof Kozlowski wrote:
> >>> diff --git a/arch/arm/boot/dts/qcom-ipq4019.dtsi b/arch/arm/boot/dts/qcom-ipq4019.dtsi
> >>> index b23591110bd2..5fa1af147df9 100644
> >>> --- a/arch/arm/boot/dts/qcom-ipq4019.dtsi
> >>> +++ b/arch/arm/boot/dts/qcom-ipq4019.dtsi
> >>> @@ -38,6 +38,7 @@ aliases {
> >>>  		spi1 = &blsp1_spi2;
> >>>  		i2c0 = &blsp1_i2c3;
> >>>  		i2c1 = &blsp1_i2c4;
> >>> +		ethernet0 = &gmac;
> >>
> >> Hm, I have doubts about this one. Why alias is needed and why it is a
> >> property of a SoC? Not every board has Ethernet enabled, so this looks
> >> like board property.
> >>
> >> I also wonder why do you need it at all?
> > 
> > In general, Ethernet aliases are needed so that the bootloader can fix
> > up the MAC address of each port's OF node with values it gets from the
> > U-Boot environment or an AT24 EEPROM or something like that.
> 
> Assuming that's the case here, my other part of question remains - is
> this property of SoC or board? The buses (SPI, I2C) are properties of
> boards, even though were incorrectly put here. If the board has multiple
> ethernets, the final ordering is the property of the board, not SoC. I
> would assume that bootloader also configures the MAC address based on
> the board config, not per SoC...

I don't disagree. On NXP LS1028A, we also have all aliases in board
device trees and not in the SoC dtsi.