Re: [net-next v5 2/6] ARM: dts: nxp: mxs: Adjust the imx28.dtsi L2 switch description

From: Stefan Wahren
Date: Wed Apr 16 2025 - 15:16:24 EST


Hi Lukasz,

Am 14.04.25 um 16:01 schrieb Lukasz Majewski:
The current range of 'reg' property is too small to allow full control
of the L2 switch on imx287.

As this IP block also uses ENET-MAC blocks for its operation, the address
range for it must be included as well.

Moreover, some SoC common properties (like compatible, clocks, interrupts
numbers) have been moved to this node.

Signed-off-by: Lukasz Majewski <lukma@xxxxxxx>
Reviewed-by: Andrew Lunn <andrew@xxxxxxx>

---
Changes for v2:
- adding extra properties (like compatible, clocks, interupts)

Changes for v3:
- None

Changes for v4:
- Rename imx287 with imx28 (as the former is not used in kernel anymore)

Changes for v5:
- None
---
arch/arm/boot/dts/nxp/mxs/imx28.dtsi | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/arch/arm/boot/dts/nxp/mxs/imx28.dtsi b/arch/arm/boot/dts/nxp/mxs/imx28.dtsi
index bbea8b77386f..a0b565ffc83d 100644
--- a/arch/arm/boot/dts/nxp/mxs/imx28.dtsi
+++ b/arch/arm/boot/dts/nxp/mxs/imx28.dtsi
@@ -1321,8 +1321,12 @@ mac1: ethernet@800f4000 {
status = "disabled";
};
- eth_switch: switch@800f8000 {
- reg = <0x800f8000 0x8000>;
+ eth_switch: switch@800f0000 {
+ compatible = "nxp,imx28-mtip-switch";
+ reg = <0x800f0000 0x20000>;
+ interrupts = <100>, <101>, <102>;
+ clocks = <&clks 57>, <&clks 57>, <&clks 64>, <&clks 35>;
+ clock-names = "ipg", "ahb", "enet_out", "ptp";
status = "disabled";
from my understanding of device tree this file should describe the hardware, not the software implementation. After this change the switch memory region overlaps the existing mac0 and mac1 nodes.

Definition in the i.MX28 reference manual:
ENET MAC0 ENET 0x800F0000 - 0x800F3FFF 16KB
ENET MAC1 ENET 0x800F4000 - 0x800F7FFF 16KB
ENT Switch SWITCH 0x800F8000 - 0x800FFFFF 32KB

I'm not the expert how to solve this properly. Maybe two node references to mac0 and mac1 under eth_switch in order to allocate the memory regions separately.

Sorry, if i missed a possible discussion about this before.

Regards
};
};