[U-Boot-Users] A question about sdram_init

[Wolfgang Denk]

In message <BAY2-F150B8F0GuRQm600014934 at hotmail.com> you wrote:
> To explain the problem easier, I stripped down the sdram_init() to three DCR 
> instructions:

I guess this is on a MIPS64 system? Or ARM9? Or x86, or what?

> 1. The sdram() hanged after 2nd line, i.e. after set up 4MB. But it didn't 
> go through 3rd line and didn't return.

How did you know where it hangs? Did you use a debugger?

> 2. If the 1st line is commented, i.e. not disable everything, sdram() could 
> return.

How do you know your code is correct?

> 3. Since sdram() is called from start.S, I rewrote all these code in start.S 
> in assembly language and let them run in start.S (commented out "bl 
> sdram_init"), these three lines can run without any problem. They didn't 
> interfere each other.

There is no difference between C code and assembly - unless you wrote
different code.

Best regards,

Wolfgang Denk

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Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
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