ahci: add DT binding for Calxeda AHCI controller

Add devicetree match table to ahci platform driver for Calxeda Highbank
AHCI controller.

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Jeff Garzik <jgarzik@pobox.com>
Cc: linux-ide@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: devicetree-discuss@lists.ozlabs.org
diff --git a/Documentation/devicetree/bindings/ata/calxeda-sata.txt b/Documentation/devicetree/bindings/ata/calxeda-sata.txt
new file mode 100644
index 0000000..79caa56
--- /dev/null
+++ b/Documentation/devicetree/bindings/ata/calxeda-sata.txt
@@ -0,0 +1,17 @@
+* Calxeda SATA Controller
+
+SATA nodes are defined to describe on-chip Serial ATA controllers.
+Each SATA controller should have its own node.
+
+Required properties:
+- compatible        : compatible list, contains "calxeda,hb-ahci"
+- interrupts        : <interrupt mapping for SATA IRQ>
+- reg               : <registers mapping>
+
+Example:
+        sata@ffe08000 {
+		compatible = "calxeda,hb-ahci";
+                reg = <0xffe08000 0x1000>;
+                interrupts = <115>;
+        };
+