dt-bindings: arm: atmel,at91rm9200-sdramc: convert to DT schema

Convert RAMC SDRAM/DDR controller binding to YAML format.

Signed-off-by: Akhila YS <akhilayalmati@gmail.com>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20260227-arm-microchip-v4-5-7e2ae1c5b5d6@gmail.com
Signed-off-by: Claudiu Beznea <claudiu.beznea@tuxon.dev>

Documentation/devicetree/bindings/arm/atmel,at91rm9200-sdramc.yaml

@@ -0,0 +1,66 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/arm/atmel,at91rm9200-sdramc.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Microchip (Atmel) SDRAM / DDR Controller (RAMC / DDRAMC / UDDRC)
+
+maintainers:
+  - Nicolas Ferre <nicolas.ferre@microchip.com>
+  - Claudiu Beznea <claudiu.beznea@tuxon.dev>
+
+description:
+  The SDRAM/DDR Controller (often called RAMC or DDRAMC) in various
+  Atmel/Microchip ARM9 and Cortex-A5/A7 SoCs  manages external
+  SDRAM / DDR memory. It is typically exposed as a syscon node for
+  register access from other drivers (e.g. for initialization or mode
+  configuration). No interrupts or clocks are usually required in the
+  binding.
+
+properties:
+  compatible:
+    oneOf:
+      - items:
+          - const: atmel,at91rm9200-sdramc
+          - const: syscon
+      - items:
+          - const: microchip,sama7d65-uddrc
+          - const: microchip,sama7g5-uddrc
+      - enum:
+          - atmel,at91sam9260-sdramc
+          - atmel,at91sam9g45-ddramc
+          - atmel,sama5d3-ddramc
+          - microchip,sam9x60-ddramc
+          - microchip,sam9x7-ddramc
+          - microchip,sama7g5-uddrc
+
+  reg:
+    maxItems: 1
+
+  clocks:
+    minItems: 1
+    maxItems: 2
+
+  clock-names:
+    minItems: 1
+    items:
+      - const: ddrck
+      - const: mpddr
+
+required:
+  - compatible
+  - reg
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/clock/at91.h>
+    ramc@ffffe400 {
+        compatible = "atmel,at91sam9g45-ddramc";
+        reg = <0xffffe400 0x200>;
+        clocks = <&pmc PMC_TYPE_SYSTEM 2>;
+        clock-names = "ddrck";
+    };
+...

Documentation/devicetree/bindings/arm/atmel-sysregs.txt

@@ -1,20 +0,0 @@
-Atmel system registers
-
-RAMC SDRAM/DDR Controller required properties:
-- compatible: Should be "atmel,at91rm9200-sdramc", "syscon" or
-			"atmel,at91sam9260-sdramc" or
-			"atmel,at91sam9g45-ddramc" or
-			"atmel,sama5d3-ddramc" or
-			"microchip,sam9x60-ddramc" or
-			"microchip,sama7g5-uddrc" or
-			"microchip,sama7d65-uddrc", "microchip,sama7g5-uddrc" or
-			"microchip,sam9x7-ddramc", "atmel,sama5d3-ddramc".
-- reg: Should contain registers location and length
-
-Examples:
-
-	ramc0: ramc@ffffe800 {
-		compatible = "atmel,at91sam9g45-ddramc";
-		reg = <0xffffe800 0x200>;
-	};
-