[PATCH V2 RFC 2/2] ARM: dts: BCM5301X: change Luxul XWR-3150 CPU port from 5 do 8

From: Rafał Miłecki <[email protected]>

Northstar devices have 3 CPU ports (each connected to a different
Ethernet interface). This design was meant for dual IMP setups when
WAN traffic goes to port 5 and LAN traffic goes to port 8.

For practical reasons we label only one of those ports as "cpu" (the
rest remains disabled). It's because of Linux behaviour (and it's
probably a bad thing since DT shouldn't "care" that that).

So far the choice of "cpu" port was based on how vendor decided to setup
given device originally: which of three Ethernet interfaces got MAC
assigned and which port was used by vendor original firmware.

Most vendors decided to use CPU port 5 & relevant Ethernet interface.
The problem is that only switch port 8 provides full functionality.

Change the choice of "cpu" port to 8 and make the third Ethernet
interface (connected to port 8) use MAC designed for the first Ethernet
interface (connected to port 5). This makes Linux use switch in a
feature full way.

Signed-off-by: Rafał Miłecki <[email protected]>
---
This seems to be a slight abuse of DT. Instead of describing hardware we
make it steer Linux into using a more appropriate switch port. This
isn't strictly a setback on its own. It's a change from one choice to
another.

I'm not sure about that MAC however. We say that the third Ethernet
interface should use MAC that was designed for the first one.

Is all of that acceptable?

 .../arm/boot/dts/broadcom/bcm47094-luxul-xwr-3150-v1.dts | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/arch/arm/boot/dts/broadcom/bcm47094-luxul-xwr-3150-v1.dts b/arch/arm/boot/dts/broadcom/bcm47094-luxul-xwr-3150-v1.dts
index 8e487f60a2cc..7969f0f331b5 100644
--- a/arch/arm/boot/dts/broadcom/bcm47094-luxul-xwr-3150-v1.dts
+++ b/arch/arm/boot/dts/broadcom/bcm47094-luxul-xwr-3150-v1.dts
@@ -81,6 +81,11 @@ &gmac0 {
 	nvmem-cell-names = "mac-address";
 };
 
+&gmac2 {
+	nvmem-cells = <&et0macaddr 0>;
+	nvmem-cell-names = "mac-address";
+};
+
 &pcie_bridge0 {
 	wifi@0,0 {
 		compatible = "brcm,bcm4366-fmac", "brcm,bcm4329-fmac";
@@ -136,7 +141,7 @@ port@4 {
 		};
 
 		port@5 {
-			label = "cpu";
+			status = "disabled";
 		};
 
 		port@7 {
@@ -144,7 +149,7 @@ port@7 {
 		};
 
 		port@8 {
-			status = "disabled";
+			label = "cpu";
 		};
 	};
 };
-- 
2.51.0