X-Git-Url: https://git.karo-electronics.de/?a=blobdiff_plain;f=doc%2FREADME.b4860qds;h=6fcc3bd6e8ae4b4c6a99f9c6b5bcf39ad920c131;hb=36c56ebc6046aa81a82dd3e1572a28f50e02a4a7;hp=3da77d9f0f83a000e1676cf00d11c553cc4ed046;hpb=e7222b5f494443f26e8c1aa3d016ea0d7c812203;p=karo-tx-uboot.git

diff --git a/doc/README.b4860qds b/doc/README.b4860qds
index 3da77d9f0f..6fcc3bd6e8 100644
--- a/doc/README.b4860qds
+++ b/doc/README.b4860qds
@@ -119,7 +119,7 @@ B4860QDS Default Settings
 Switch Settings
 ----------------
 
-SW1	OFF [0]	OFF [1]	OFF [1]	OFF [0]	OFF [1]	OFF [0]	OFF [1]	OFF [1]
+SW1	OFF [0]	OFF [0]	OFF [0]	OFF [0]	OFF [0]	OFF [0]	OFF [0]	OFF [0]
 SW2	ON	ON	ON	ON	ON	ON	OFF	OFF
 SW3	OFF	OFF	OFF	ON	OFF	OFF	ON	OFF
 SW5	OFF	OFF	OFF	OFF	OFF	OFF	ON	ON
@@ -328,3 +328,39 @@ The below commands apply to both B4860QDS and B4420QDS.
    On Linux the interfaces are renamed as:
 	. eth2 -> fm1-gb2
 	. eth3 -> fm1-gb3
+
+NAND boot with 2 Stage boot loader
+----------------------------------
+PBL initialise the internal SRAM and copy SPL(160KB) in SRAM.
+SPL further initialise DDR using SPD and environment variables and copy
+u-boot(768 KB) from flash to DDR.
+Finally SPL transer control to u-boot for futher booting.
+
+SPL has following features:
+ - Executes within 256K
+ - No relocation required
+
+ Run time view of SPL framework during  boot :-
+ -----------------------------------------------
+ Area        | Address                         |
+-----------------------------------------------
+ Secure boot | 0xFFFC0000 (32KB)               |
+ headers     |                                 |
+ -----------------------------------------------
+ GD, BD      | 0xFFFC8000 (4KB)                |
+ -----------------------------------------------
+ ENV         | 0xFFFC9000 (8KB)                |
+ -----------------------------------------------
+ HEAP        | 0xFFFCB000 (30KB)               |
+ -----------------------------------------------
+ STACK       | 0xFFFD8000 (22KB)               |
+ -----------------------------------------------
+ U-boot SPL  | 0xFFFD8000 (160KB)              |
+ -----------------------------------------------
+
+NAND Flash memory Map on B4860 and B4420QDS
+------------------------------------------
+ Start		 End		Definition			Size
+0x000000	0x0FFFFF	u-boot                          1MB
+0x140000	0x15FFFF	u-boot env                      128KB
+0x1A0000	0x1BFFFF	FMAN Ucode                      128KB