Hi all:
Now I am working on a EP7312 board with uboot and I have been blocked by a unknown problem for several week.Before descride the problem,let me intrduce my working flow.
I compile u-boot under rh linux 7.3 with cross-compile tools download from arm.linux.org.uk.
At the time I get u-boot.bin via cross-compile, I generate u-boot.asm by "arm-linux-objdump -d u-boot > u-boot.asm"
Then program the u-boot.bin to flash(sst29vf040) with programmer. Switch the ep7312 board to external boot mode ,and begin boot.
I use ICE and ADS 1.2 to trace how the board works.And I can trace that u-boot has init the ep7312 board and has relocated it self form flash(0x0) to sdram (0xc0f00000).
The following is a piece of code in the sdram: (near the start of <start_armboot>) ------------------------------------------------ c0f00a50: [0xe92d40f0] stmfd r13!,{r4-r7,r14} c0f00a54: [0xe24dd088] sub r13,r13,#0x88 c0f00a58: [0xe28d8068] add r8,r13,#0x68 c0f00a5c: [0xe1a00008] mov r0,r8 c0f00a60: [0xe3a01000] mov r1,#0 c0f00a64: [0xe3a02020] mov r2,#0x20 c0f00a68: [0xeb002826] bl 0xc0f0ab08 -------------------------------------------------
please note the last line :(wrong,u-boot crashes here) ------------------------------------------------- c0f00a68: [0xeb002826] bl 0xc0f0ab08 -------------------------------------------------
In u-boot.asm and in flash ,this piece of code was: ------------------------------------------------- c0f00a50 <start_armboot>: c0f00a50: e92d40f0 stmdb sp!, {r4, r5, r6, r7, lr} c0f00a54: e24dd088 sub sp, sp, #136 ; 0x88 c0f00a58: e28d8068 add r8, sp, #104 ; 0x68 c0f00a5c: e1a00008 mov r0, r8 c0f00a60: e3a01000 mov r1, #0 ; 0x0 c0f00a64: e3a02020 mov r2, #32 ; 0x20 c0f00a68: eb002926 bl c0f0af08 <memset> -------------------------------------------------
where the last line was :(right,u-boot jump to <memset>)
------------------------------------------------- c0f00a68: eb002926 bl c0f0af08 <memset> -------------------------------------------------
we can compare the wrong and right line and find that the two BL address have a discrepancy of 0x400. (c0f0ab08 and c0f0af08).This makes u-boot to crash.
I have been blocked here for several weeks.The content of u-boot.asm seems all right and in flash it does.But why after relocating to sdram the BL operating number subtracts 0x400?
------------------------------------------------------ the detailed info of my ep7312 board is as follows:
cpu : EP7312 sdram: (4 bank * 1M * 16 bit) * 2 flash: 512k * 8 bit cs0 has been set to 8bit,slowest.
ep7312.h and memsetup.S also attached. -------------------------------------------------------
Any one can help? Thanks in advance!
Pure
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