ARM: zynq: Add jtag distro boot support

This patch adds new jtag distro boot command to look for bootscript
file in DDR and execute it first incase of jtag bootmode.

Signed-off-by: T Karthik Reddy <t.karthik.reddy@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
diff --git a/board/xilinx/zynq/board.c b/board/xilinx/zynq/board.c
index 390d948..420a5ca 100644
--- a/board/xilinx/zynq/board.c
+++ b/board/xilinx/zynq/board.c
@@ -50,7 +50,7 @@
 		env_set("modeboot", "sdboot");
 		break;
 	case ZYNQ_BM_JTAG:
-		mode = "pxe dhcp";
+		mode = "jtag pxe dhcp";
 		env_set("modeboot", "jtagboot");
 		break;
 	default:
diff --git a/include/configs/zynq-common.h b/include/configs/zynq-common.h
index 22486c0..2d53237 100644
--- a/include/configs/zynq-common.h
+++ b/include/configs/zynq-common.h
@@ -176,7 +176,16 @@
 #define BOOTENV_DEV_NAME_NOR(devtypeu, devtypel, instance) \
 	"nor "
 
+#define BOOT_TARGET_DEVICES_JTAG(func)  func(JTAG, jtag, na)
+
+#define BOOTENV_DEV_JTAG(devtypeu, devtypel, instance) \
+	"bootcmd_jtag=source $scriptaddr; echo SCRIPT FAILED: continuing...;\0"
+
+#define BOOTENV_DEV_NAME_JTAG(devtypeu, devtypel, instance) \
+	"jtag "
+
 #define BOOT_TARGET_DEVICES(func) \
+	BOOT_TARGET_DEVICES_JTAG(func) \
 	BOOT_TARGET_DEVICES_MMC(func) \
 	BOOT_TARGET_DEVICES_QSPI(func) \
 	BOOT_TARGET_DEVICES_NAND(func) \