armv8/ls2085aqds: NAND boot support
This adds NAND boot support for LS2085AQDS, using SPL framework.
Details of forming NAND image can be found in README.
Signed-off-by: Scott Wood <scottwood@freescale.com>
[York Sun: Remove +S from defconfig after commit 252ed872]
Signed-off-by: York Sun <yorksun@freescale.com>
diff --git a/arch/arm/cpu/armv8/fsl-lsch3/README b/arch/arm/cpu/armv8/fsl-lsch3/README
index 4f36e2a..15a1549 100644
--- a/arch/arm/cpu/armv8/fsl-lsch3/README
+++ b/arch/arm/cpu/armv8/fsl-lsch3/README
@@ -95,3 +95,41 @@
mcmemsize: MC DRAM block size. If this variable is not defined, the value
CONFIG_SYS_LS_MC_DRAM_BLOCK_MIN_SIZE will be assumed.
+
+Booting from NAND
+-------------------
+Booting from NAND requires two images, RCW and u-boot-with-spl.bin.
+The difference between NAND boot RCW image and NOR boot image is the PBI
+command sequence. Below is one example for PBI commands for QDS which uses
+NAND device with 2KB/page, block size 128KB.
+
+1) CCSR 4-byte write to 0x00e00404, data=0x00000000
+2) CCSR 4-byte write to 0x00e00400, data=0x1800a000
+The above two commands set bootloc register to 0x00000000_1800a000 where
+the u-boot code will be running in OCRAM.
+
+3) Block Copy: SRC=0x0107, SRC_ADDR=0x00020000, DEST_ADDR=0x1800a000,
+BLOCK_SIZE=0x00014000
+This command copies u-boot image from NAND device into OCRAM. The values need
+to adjust accordingly.
+
+SRC should match the cfg_rcw_src, the reset config pins. It depends
+ on the NAND device. See reference manual for cfg_rcw_src.
+SRC_ADDR is the offset of u-boot-with-spl.bin image in NAND device. In
+ the example above, 128KB. For easy maintenance, we put it at
+ the beginning of next block from RCW.
+DEST_ADDR is fixed at 0x1800a000, matching bootloc set above.
+BLOCK_SIZE is the size to be copied by PBI.
+
+RCW image should be written to the beginning of NAND device. Example of using
+u-boot command
+
+nand write <rcw image in memory> 0 <size of rcw image>
+
+To form the NAND image, build u-boot with NAND config, for example,
+ls2085aqds_nand_defconfig. The image needed is u-boot-with-spl.bin.
+The u-boot image should be written to match SRC_ADDR, in above example 0x20000.
+
+nand write <u-boot image in memory> 200000 <size of u-boot image>
+
+With these two images in NAND device, the board can boot from NAND.