1QSPI Boot source support Overview
2-------------------
3	1. LS1043A
4		LS1043AQDS
5	2. LS2080A
6		LS2080AQDS
7	3. LS1012A
8		LS1012AQDS
9		LS1012ARDB
10	4. LS1046A
11		LS1046AQDS
12		LS1046ARDB
13
14Booting from QSPI
15-------------------
16Booting from QSPI requires two images, RCW and u-boot-dtb.bin.
17The difference between QSPI boot RCW image and NOR boot image is the PBI
18command sequence for setting the boot location pointer. It's should point
19to the address for u-boot in QSPI flash.
20
21RCW image should be written to the beginning of QSPI flash device.
22Example of using u-boot command
23
24=> sf probe 0:0
25SF: Detected S25FL256S_64K with page size 256 Bytes, erase size 64 KiB, total 32 MiB
26=> sf erase 0 +<size of rcw image>
27SF: 65536 bytes @ 0x0 Erased: OK
28=> sf write <rcw image in memory> 0 <size of rcw image>
29SF: 164 bytes @ 0x0 Written: OK
30
31To get the QSPI image, build u-boot with QSPI config, for example,
32<board_name>_qspi_defconfig. The image needed is u-boot-dtb.bin.
33The u-boot image should be written to 0x10000(but 0x1000 for LS1043A, LS2080A).
34
35=> sf probe 0:0
36SF: Detected S25FL256S_64K with page size 256 Bytes, erase size 64 KiB, total 32 MiB
37=> sf erase 10000 +<size of u-boot image>
38SF: 589824 bytes @ 0x10000 Erased: OK
39=> sf write <u-boot image in memory> 10000 <size of u-boot image>
40SF: 580966 bytes @ 0x10000 Written: OK
41
42With these two images in QSPI flash device, the board can boot from QSPI.
43