arm: ls102xa: Add SD boot support for LS1021AQDS board

This patch adds SD boot support for LS1021AQDS board. SPL
framework is used. PBL initialize the internal RAM and copy
SPL to it, then SPL initialize DDR using SPD and copy u-boot
from SD card to DDR, finally SPL transfer control to u-boot.

Signed-off-by: Alison Wang <alison.wang@freescale.com>
Signed-off-by: Jason Jin <jason.jin@freescale.com>
Reviewed-by: York Sun <yorksun@freescale.com>
diff --git a/board/freescale/ls1021aqds/ls102xa_pbi.cfg b/board/freescale/ls1021aqds/ls102xa_pbi.cfg
new file mode 100644
index 0000000..f1a1b63
--- /dev/null
+++ b/board/freescale/ls1021aqds/ls102xa_pbi.cfg
@@ -0,0 +1,12 @@
+#PBI commands
+
+09570200 ffffffff
+09570158 00000300
+8940007c 21f47300
+
+#Configure Scratch register
+09ee0200 10000000
+#Configure alternate space
+09570158 00001000
+#Flush PBL data
+096100c0 000FFFFF