dt-bindings: dma: ti: k3-bcdma: Describe cfg register regions

Block copy DMA(BCDMA)module on K3 SoCs have ring, BCHAN, TX and RX
channel cfg register regions which are usually configured by a Device
Management firmware. But certain entities such as bootloader (like
U-Boot) may have to access them directly. Describe this region in the
binding documentation for completeness of module description.

Keep the binding compatible with existing DTS files by requiring first
five regions to be present at least.

Signed-off-by: Vignesh Raghavendra <[e-mail]>
Reviewed-by: Krzysztof Kozlowski <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Vinod Koul <[e-mail]>

Documentation/devicetree/bindings/dma/ti/k3-bcdma.yaml

···
 
   reg:
     minItems: 3
-    maxItems: 5
+    maxItems: 9
 
   reg-names:
     minItems: 3
-    maxItems: 5
+    maxItems: 9
 
   "#dma-cells":
     const: 3
···
     then:
       properties:
         reg:
+          minItems: 5
           items:
             - description: BCDMA Control /Status Registers region
             - description: Block Copy Channel Realtime Registers region
             - description: RX Channel Realtime Registers region
             - description: TX Channel Realtime Registers region
             - description: Ring Realtime Registers region
+            - description: Ring Configuration Registers region
+            - description: TX Channel Configuration Registers region
+            - description: RX Channel Configuration Registers region
+            - description: Block Copy Channel Configuration Registers region
 
         reg-names:
+          minItems: 5
           items:
             - const: gcfg
             - const: bchanrt
             - const: rchanrt
             - const: tchanrt
             - const: ringrt
+            - const: ring
+            - const: tchan
+            - const: rchan
+            - const: bchan
 
       required:
         - ti,sci-rm-range-bchan
···
                       <0x0 0x4c000000 0x0 0x20000>,
                       <0x0 0x4a820000 0x0 0x20000>,
                       <0x0 0x4aa40000 0x0 0x20000>,
-                      <0x0 0x4bc00000 0x0 0x100000>;
-                reg-names = "gcfg", "bchanrt", "rchanrt", "tchanrt", "ringrt";
+                      <0x0 0x4bc00000 0x0 0x100000>,
+                      <0x0 0x48600000 0x0 0x8000>,
+                      <0x0 0x484a4000 0x0 0x2000>,
+                      <0x0 0x484c2000 0x0 0x2000>,
+                      <0x0 0x48420000 0x0 0x2000>;
+                reg-names = "gcfg", "bchanrt", "rchanrt", "tchanrt", "ringrt",
+                            "ring", "tchan", "rchan", "bchan";
                 msi-parent = <&inta_main_dmss>;
                 #dma-cells = <3>;