ARM: dts: dra7: add support for parallel NAND flash

DRA7xx platform has in-build GPMC and ELM h/w engines which can be used
for accessing externel NAND flash device. This patch:
- adds generic DT binding in dra7.dtsi for enabling GPMC and ELM h/w engines
- adds DT binding for Micron NAND Flash (MT29F2G16AADWP) present on dra7-evm
*Important*
	On DRA7 EVM, GPMC_WPN and NAND_BOOTn are controlled by DIP switch
	So following board settings are required for NAND device detection:
	SW5.9 (GPMC_WPN) = LOW
	SW5.1 (NAND_BOOTn) = HIGH

Signed-off-by: Minal Shah <minalkshah@gmail.com>
Signed-off-by: Pekon Gupta <pekon@ti.com>
Reviewed-by: Javier Martinez Canillas <javier@dowhile0.org>
Signed-off-by: Tony Lindgren <tony@atomide.com>
diff --git a/arch/arm/boot/dts/dra7.dtsi b/arch/arm/boot/dts/dra7.dtsi
index 6af8b08..a8a0cee 100644
--- a/arch/arm/boot/dts/dra7.dtsi
+++ b/arch/arm/boot/dts/dra7.dtsi
@@ -964,6 +964,26 @@
 				dr_mode = "otg";
 			};
 		};
+
+		elm: elm@48078000 {
+			compatible = "ti,am3352-elm";
+			reg = <0x48078000 0xfc0>;      /* device IO registers */
+			interrupts = <GIC_SPI 4 IRQ_TYPE_LEVEL_HIGH>;
+			ti,hwmods = "elm";
+			status = "disabled";
+		};
+
+		gpmc: gpmc@50000000 {
+			compatible = "ti,am3352-gpmc";
+			ti,hwmods = "gpmc";
+			reg = <0x50000000 0x37c>;      /* device IO registers */
+			interrupts = <GIC_SPI 20 IRQ_TYPE_LEVEL_HIGH>;
+			gpmc,num-cs = <8>;
+			gpmc,num-waitpins = <2>;
+			#address-cells = <2>;
+			#size-cells = <1>;
+			status = "disabled";
+		};
 	};
 };