Hi,
The monitor port can work on my custom board but u-boot hang or crashes after relocation.I read the DULG FAQ about the answer.I,however,want to make sure about the fact why the same SDRAM init code does work on RPXlite but in vain on my custom board for the SDRAM hardware design are the same with these two boards.
I am sure that my UPMA RAM WORD is OK because of successful relocation.When I traced the code using BDI2000 and found that the code often went wrong after start.S:574.
/* * We are done. Do not return, instead branch to second part of board * initialization, now running from RAM. */
572 addi r0, r10, in_ram - _start + EXC_OFF_SYS_RESET 573 mtlr r0 574 blr
BDI>ci - TARGET: target has entered debug mode BDI>i Target state : debug mode Debug entry cause : entering check stop state Current PC : 0x00000200
Meanwhile,I checked the signal of SDRAM chip(MT48LC16M16)by WAVEFORM and noticed that A[20-29] & D[0-31] on RPXlite board have 1KHz plus whereas zero
level on my board after reset.
Is this realated with my hardware design or just software adjustment is enough?
Any hints is welcome!
Thanks in advance and Happy New Year!!!
SAM SONG
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