mx6: Add initial SPL support for HummingBoard-i2eX

Add the initial SPL support for HummingBoard-i2eX, which is based on a
MX6 Dual.

For more information about HummingBoard, please check:
http://www.solid-run.com/products/hummingboard/

Based on the work from Jon Nettleton and Rabeeh Khoury.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
diff --git a/board/solidrun/mx6cuboxi/README b/board/solidrun/mx6cuboxi/README
new file mode 100644
index 0000000..3050c48
--- /dev/null
+++ b/board/solidrun/mx6cuboxi/README
@@ -0,0 +1,21 @@
+How to use U-boot on Solid-run mx6 hummingboard
+-----------------------------------------------
+
+- Build U-boot for hummingboard:
+
+$ make mrproper
+$ make mx6cuboxi_defconfig
+$ make
+
+This will generate the SPL image called SPL and the u-boot.img.
+
+- Flash the SPL image into the SD card:
+
+sudo dd if=SPL of=/dev/mmcblk0 bs=1k seek=1; sync
+
+- Flash the u-boot.img image into the SD card:
+
+sudo dd if=u-boot.img of=/dev/mmcblk0 bs=1k seek=69; sync
+
+- Insert the SD card in the hummingboard, power it up and U-boot messages
+should come up.