[PATCH] ARM: dts: aspeed: clemente: add MCTP over I2C support

[PATCH] ARM: dts: aspeed: clemente: add MCTP over I2C support

[Leo Wang]

Enable MCTP communication on the Meta Clemente BMC board:

- Add an MCTP I2C controller node at address 0x10 on I2C0
- Mark selected I2C mux channels as MCTP controllers
- Remove unused "i2c-mux-idle-disconnect" properties

This allows MCTP devices to be discovered and used for
management communication on the Clemente platform.

Signed-off-by: Leo Wang <leo.jt.wang@gmail.com>
---
 arch/arm/boot/dts/aspeed/aspeed-bmc-facebook-clemente.dts | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/arch/arm/boot/dts/aspeed/aspeed-bmc-facebook-clemente.dts b/arch/arm/boot/dts/aspeed/aspeed-bmc-facebook-clemente.dts
index a614f947dafc9a6628c3f3d45b62ff3ca9d2b618..a2f0ed6e7bbefbdcec33f7ddebdf2de62adec164 100644
--- a/arch/arm/boot/dts/aspeed/aspeed-bmc-facebook-clemente.dts
+++ b/arch/arm/boot/dts/aspeed/aspeed-bmc-facebook-clemente.dts
@@ -269,18 +269,23 @@ &gpio1 {
 
 &i2c0 {
 	status = "okay";
+	multi-master;
+	mctp@10 {
+		compatible = "mctp-i2c-controller";
+		reg = <(0x10 | I2C_OWN_SLAVE_ADDRESS)>;
+	};
 
 	i2c-mux@71 {
 		compatible = "nxp,pca9546";
 		reg = <0x71>;
 		#address-cells = <1>;
 		#size-cells = <0>;
-		i2c-mux-idle-disconnect;
 
 		i2c0mux0ch0: i2c@0 {
 			#address-cells = <1>;
 			#size-cells = <0>;
 			reg = <0>;
+			mctp-controller;
 		};
 
 		i2c0mux0ch1: i2c@1 {
@@ -332,6 +337,7 @@ i2c0mux0ch2: i2c@2 {
 			#address-cells = <1>;
 			#size-cells = <0>;
 			reg = <2>;
+			mctp-controller;
 		};
 
 		i2c0mux0ch3: i2c@3 {
@@ -457,12 +463,12 @@ i2c-mux@75 {
 		reg = <0x75>;
 		#address-cells = <1>;
 		#size-cells = <0>;
-		i2c-mux-idle-disconnect;
 
 		i2c0mux3ch0: i2c@0 {
 			#address-cells = <1>;
 			#size-cells = <0>;
 			reg = <0>;
+			mctp-controller;
 		};
 
 		i2c0mux3ch1: i2c@1 {
@@ -514,6 +520,7 @@ i2c0mux3ch2: i2c@2 {
 			#address-cells = <1>;
 			#size-cells = <0>;
 			reg = <2>;
+			mctp-controller;
 		};
 
 		i2c0mux3ch3: i2c@3 {

---
base-commit: c65261717599d419e9c683d85f515d3ca2261549
change-id: 20250918-leo-dts-transceiver-edc31e3c21af

Best regards,
-- 
Leo Wang <leo.jt.wang@gmail.com>

Re: [PATCH] ARM: dts: aspeed: clemente: add MCTP over I2C support

[Andrew Jeffery]

Hi Leo,

On Thu, 2025-09-18 at 17:43 +0800, Leo Wang wrote:
> Enable MCTP communication on the Meta Clemente BMC board:
> 
> - Add an MCTP I2C controller node at address 0x10 on I2C0
> - Mark selected I2C mux channels as MCTP controllers
> - Remove unused "i2c-mux-idle-disconnect" properties

> 
> This allows MCTP devices to be discovered and used for
> management communication on the Clemente platform.

This description covers details we can see in the patch itself. Can you
please rather describe the motivation and any related considerations,
e.g. answer:

 * What devices will you be managing via MCTP?
 * How do they affect the function of the platform?
    - Alternatively, how does _not_ having the MCTP capability to manage
      them impact the function of the platform?

The general advice provided here might be helpful:

https://docs.kernel.org/process/submitting-patches.html#describe-your-changes

Andrew