[U-Boot] hi, I could not understand the memsize.c, somebody help me?

[Detlev Zundel]

Hi,

> thanks for your reply.
> sorry for my ability of writing and understanding the code
> =D
>
> btw, How contribute my idea of this function, I means, it should be more
>  clean or easy just like this:
>
>
> unsigned long get_ram_size(volatile long *base, long maxsize)
> {
>
>         unsigned long mem;
>         for (mem = (*base); mem < (maxsize); mem <<= 1)) {
>                 if (*(unsigned long *)((unsigned long)(get_ram_size) + mem) ==
>                     *(unsigned long *)(get_ram_size))
>                         break;
>         }
> }

This will not work at all, sorry .  Before suggesting changes which
should be "more clean or easy", at least test them on real hardware.
You will find out that this code has lots of errors.

Some hints: 

SW: What addresses is the original code accessing?  What addresses are
    you accessing?  What values do you expect there?

HW: How does the algorithm in get_ram_size work at all?  What
    transactions does it produce on the CPU busses?  What transactions
    will your code produce?  Do you know what the CPU will do if it
    accesses RAM that is not available?

Please believe me, there is definitely *quite a bit* of understanding of
hard- and software in the current code.  If you do not know what the
questions above mean, it is highly unlikely that you can improve the
code.

Best wishes
  Detlev

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