[PATCH v3 2/8] dt-bindings: net: amlogic,meson-dwmac: add amlogic,t7-dwmac

[Lucas Tanure]

The T7 has the same ethernet glue as the G12A, but needs two clocks of
its own. The controller reaches memory through a pipeline stage with a
gate of its own; nothing else claims it, so it is switched off as
unused and the port can no longer finish a transfer. The glue registers
sit in a block clocked together with the MDIO multiplexer, which only
probes after the controller has programmed them: with the clock still
off those writes are lost, and the port keeps whatever delays the
bootloader left behind.

So the T7 gets its own clock list, without the timing adjustment clock
it never uses. The delays follow ethernet-controller.yaml, so the
vendor properties are not valid here.

Assisted-by: LLM
Signed-off-by: Lucas Tanure <tanure at linux.com>
---
 .../bindings/net/amlogic,meson-dwmac.yaml     | 56 +++++++++++++++++++
 1 file changed, 56 insertions(+)

diff --git a/Documentation/devicetree/bindings/net/amlogic,meson-dwmac.yaml b/Documentation/devicetree/bindings/net/amlogic,meson-dwmac.yaml
index 90ef79161ab1..2353dd9181ed 100644
--- a/Documentation/devicetree/bindings/net/amlogic,meson-dwmac.yaml
+++ b/Documentation/devicetree/bindings/net/amlogic,meson-dwmac.yaml
@@ -23,6 +23,7 @@ select:
           - amlogic,meson-gxbb-dwmac
           - amlogic,meson-axg-dwmac
           - amlogic,meson-g12a-dwmac
+          - amlogic,t7-dwmac
   required:
     - compatible
 
@@ -57,6 +58,56 @@ allOf:
             - const: clkin1
             - const: timing-adjustment
 
+  - if:
+      properties:
+        compatible:
+          contains:
+            const: amlogic,t7-dwmac
+    then:
+      properties:
+        clocks:
+          items:
+            - description: GMAC main clock
+            - description: First parent clock of the internal mux
+            - description: Second parent clock of the internal mux
+            - description:
+                clock of the pipeline stage inserted in the bus path between
+                the controller and the DRAM. Without it, the controller cannot
+                complete DMA transfers.
+            - description:
+                clock of the register block holding PRG_ETH0 and PRG_ETH1.
+                Without it, the block reads as zero and ignores writes.
+
+        clock-names:
+          items:
+            - const: stmmaceth
+            - const: clkin0
+            - const: clkin1
+            - const: pipeline
+            - const: pclk
+
+        # The TX delay is a quarter of the RGMII clock period per step,
+        # which is 2ns at 1Gbit/s.
+        tx-internal-delay-ps:
+          enum: [0, 2000, 4000, 6000]
+          default: 0
+
+        rx-internal-delay-ps:
+          default: 0
+
+  # Delay definitions for Meson8b and newer
+  - if:
+      properties:
+        compatible:
+          contains:
+            enum:
+              - amlogic,meson8b-dwmac
+              - amlogic,meson8m2-dwmac
+              - amlogic,meson-gxbb-dwmac
+              - amlogic,meson-axg-dwmac
+              - amlogic,meson-g12a-dwmac
+    then:
+      properties:
         amlogic,tx-delay-ns:
           enum: [0, 2, 4, 6]
           default: 2
@@ -106,6 +157,7 @@ allOf:
           contains:
             enum:
               - amlogic,meson-g12a-dwmac
+              - amlogic,t7-dwmac
     then:
       properties:
         rx-internal-delay-ps:
@@ -143,6 +195,10 @@ properties:
               - amlogic,meson6-dwmac
               - amlogic,meson8m2-dwmac
           - const: snps,dwmac
+      - items:
+          - const: amlogic,t7-dwmac
+          - const: snps,dwmac-5.10a
+          - const: snps,dwmac
 
   reg:
     items:
-- 
2.56.0