[PATCH v2] arm64: dts: ti: k3-am62p: use eFuse MAC Address for CPSW3G Port 1

From: Siddharth Vadapalli
Date: Thu Apr 04 2024 - 04:19:14 EST


Add the "cpsw-mac-efuse" node within "wkup_conf" node corresponding to the
CTRLMMR_MAC_IDx registers within the CTRL_MMR space. Assign the compatible
"ti,am62p-cpsw-mac-efuse" to enable "syscon_regmap" operations on these
registers. The MAC Address programmed in the eFuse is accessible through
the CTRLMMR_MAC_IDx registers. The "ti,syscon-efuse" device-tree property
points to the CTRLMMR_MAC_IDx registers, allowing the CPSW driver to fetch
the MAC Address and assign it to the network interface associated with
CPSW3G MAC Port 1.

Signed-off-by: Siddharth Vadapalli <s-vadapalli@xxxxxx>
---

This patch is based on linux-next tagged next-20240404.
Patch depends on:
https://patchwork.kernel.org/project/linux-arm-kernel/patch/20240402105708.4114146-1-s-vadapalli@xxxxxx/
for the newly added "ti,am62p-cpsw-mac-efuse" compatible.

v1:
https://patchwork.kernel.org/project/linux-arm-kernel/patch/20240402094200.4036076-1-s-vadapalli@xxxxxx/
Changes since v1:
- Since "wkup_conf" is modelled as a "simple-bus" rather than being
modelled as a System Controller node with the "syscon" compatible,
directly passing the reference to the "wkup_conf" node using the
"ti,syscon-efuse" device-tree property will not work.
Therefore, I posted the patch at:
https://patchwork.kernel.org/project/linux-arm-kernel/patch/20240402105708.4114146-1-s-vadapalli@xxxxxx/
in order to add a new compatible to be used for modelling the
CTRLMMR_MAC_IDx registers as System Controller nodes, thereby
allowing the existing "ti,syscon-efuse" property to be used.
Now, "ti,syscon-efuse" points to the "cpsw_mac_efuse" node within
"wkup_conf" node, with "cpsw_mac_efuse" being a "syscon" node.

Logs verifying that the CPSW driver assigns the MAC Address from the
eFuse based on the CTRLMMR_MAC_IDx registers at 0x43000200 and 0x43000204
to the interface eth0 corresponding to CPSW3G MAC Port 1:
https://gist.github.com/Siddharth-Vadapalli-at-TI/9982c6f13bf9b8cfaf97e8517e7dea13

Regards,
Siddharth.

arch/arm64/boot/dts/ti/k3-am62p-main.dtsi | 1 +
arch/arm64/boot/dts/ti/k3-am62p-wakeup.dtsi | 5 +++++
2 files changed, 6 insertions(+)

diff --git a/arch/arm64/boot/dts/ti/k3-am62p-main.dtsi b/arch/arm64/boot/dts/ti/k3-am62p-main.dtsi
index 7337a9e13535..848ca454a411 100644
--- a/arch/arm64/boot/dts/ti/k3-am62p-main.dtsi
+++ b/arch/arm64/boot/dts/ti/k3-am62p-main.dtsi
@@ -696,6 +696,7 @@ cpsw_port1: port@1 {
label = "port1";
phys = <&phy_gmii_sel 1>;
mac-address = [00 00 00 00 00 00];
+ ti,syscon-efuse = <&cpsw_mac_efuse 0x0>;
};

cpsw_port2: port@2 {
diff --git a/arch/arm64/boot/dts/ti/k3-am62p-wakeup.dtsi b/arch/arm64/boot/dts/ti/k3-am62p-wakeup.dtsi
index a84756c336d0..df9d40f64e3b 100644
--- a/arch/arm64/boot/dts/ti/k3-am62p-wakeup.dtsi
+++ b/arch/arm64/boot/dts/ti/k3-am62p-wakeup.dtsi
@@ -18,6 +18,11 @@ chipid: chipid@14 {
reg = <0x14 0x4>;
bootph-all;
};
+
+ cpsw_mac_efuse: cpsw-mac-efuse@200 {
+ compatible = "ti,am62p-cpsw-mac-efuse", "syscon";
+ reg = <0x200 0x8>;
+ };
};

wkup_uart0: serial@2b300000 {
--
2.40.1