[net-next v2 1/4] dt-bindings: net: ftgmac100: Restrict phy-mode and delay properties for AST2600

[Jacky Chou <jacky_chou@aspeedtech.com>]

Create the new compatibles to identify AST2600 MAC0/1 and MAC3/4.
Add conditional schema constraints for Aspeed AST2600 MAC controllers:
- For "aspeed,ast2600-mac01", restrict phy-mode to "rgmii-id" and
  "rgmii-rxid", and require rx/tx-internal-delay-ps properties with 45ps
  step.
- For "aspeed,ast2600-mac23", require rx/tx-internal-delay-ps properties
  with 250ps step.
- Both require the "scu" property.
Other compatible values remain unrestricted.

Because the RGMII delay on AST2600 MAC0/1 is 45ps and its total delay
step is 32, cannot cover 2ns delay for RGMII to meet center. We need
the PHY side enables RX internal delay and the phy_mode must be
"rgmii-id" or "rgmii-rxid".

Signed-off-by: Jacky Chou <jacky_chou@aspeedtech.com>
---
 .../bindings/net/faraday,ftgmac100.yaml       | 50 +++++++++++++++++--
 1 file changed, 47 insertions(+), 3 deletions(-)

diff --git a/Documentation/devicetree/bindings/net/faraday,ftgmac100.yaml b/Documentation/devicetree/bindings/net/faraday,ftgmac100.yaml
index 55d6a8379025..82c7c81eab10 100644
--- a/Documentation/devicetree/bindings/net/faraday,ftgmac100.yaml
+++ b/Documentation/devicetree/bindings/net/faraday,ftgmac100.yaml
@@ -6,9 +6,6 @@ $schema: http://devicetree.org/meta-schemas/core.yaml#
 
 title: Faraday Technology FTGMAC100 gigabit ethernet controller
 
-allOf:
-  - $ref: ethernet-controller.yaml#
-
 maintainers:
   - Po-Yu Chuang <ratbert@faraday-tech.com>
 
@@ -21,6 +18,8 @@ properties:
               - aspeed,ast2400-mac
               - aspeed,ast2500-mac
               - aspeed,ast2600-mac
+              - aspeed,ast2600-mac01
+              - aspeed,ast2600-mac23
           - const: faraday,ftgmac100
 
   reg:
@@ -69,6 +68,12 @@ properties:
   mdio:
     $ref: /schemas/net/mdio.yaml#
 
+  scu:
+    $ref: /schemas/types.yaml#/definitions/phandle
+    description:
+      Phandle to the SCU (System Control Unit) syscon node for Aspeed platform.
+      This reference is used by the MAC controller to configure the RGMII delays.
+
 required:
   - compatible
   - reg
@@ -76,6 +81,45 @@ required:
 
 unevaluatedProperties: false
 
+allOf:
+  - $ref: ethernet-controller.yaml#
+  - if:
+      properties:
+        compatible:
+          contains:
+            const: aspeed,ast2600-mac01
+    then:
+      properties:
+        phy-mode:
+          enum: [rgmii-id, rgmii-rxid]
+        rx-internal-delay-ps:
+          minimum: 0
+          maximum: 1395
+          multipleOf: 45
+        tx-internal-delay-ps:
+          minimum: 0
+          maximum: 1395
+          multipleOf: 45
+      required:
+        - scu
+  - if:
+      properties:
+        compatible:
+          contains:
+            const: aspeed,ast2600-mac23
+    then:
+      properties:
+        rx-internal-delay-ps:
+          minimum: 0
+          maximum: 7750
+          multipleOf: 250
+        tx-internal-delay-ps:
+          minimum: 0
+          maximum: 7750
+          multipleOf: 250
+      required:
+        - scu
+
 examples:
   - |
     ethernet@1e660000 {
-- 
2.43.0