[U-Boot] cross compiling fw_printenv on big endian

[Wolfgang Denk]

Dear Joakim Tjernlund,

In message <OFF4AB0804.BE309218-ONC12576E9.003A69DF-C12576E9.003B4D86 at transmode.se> you wrote:
>
> hmm, I recently discovered that normal user space headers always define
> both __LITTLE_ENDIAN and __BIG_ENDIAN so therefore a
> # ifdef __LITTLE_ENDIAN
> #  define DO_CRC(x) crc = tab[(crc ^ (x)) & 255] ^ (crc >> 8)
> # else
> #  define DO_CRC(x) crc = tab[((crc >> 24) ^ (x)) & 255] ^ (crc << 8)
> # endif
> 
> Wont work. One have to use
>  #if __BYTE_ORDER == __LITTLE_ENDIAN
> instead.

Wenn...

3ee8c120 (Joakim Tjernlund                 2009-11-19 13:44:16 +0100 166) # ifdef __LITTLE_ENDIAN
3ee8c120 (Joakim Tjernlund                 2009-11-19 13:44:16 +0100 167) #  define DO_CRC(x) crc = tab[(crc ^ (x)) & 255] ^ (crc >> 8)
3ee8c120 (Joakim Tjernlund                 2009-11-19 13:44:16 +0100 168) # else
3ee8c120 (Joakim Tjernlund                 2009-11-19 13:44:16 +0100 169) #  define DO_CRC(x) crc = tab[((crc >> 24) ^ (x)) & 255] ^ (crc << 8)
3ee8c120 (Joakim Tjernlund                 2009-11-19 13:44:16 +0100 170) # endif


commit 3ee8c12071f0e3bdda25125b63c9d3fd54a7c9d8
Author: Joakim Tjernlund <Joakim.Tjernlund at transmode.se>
Date:   Thu Nov 19 13:44:16 2009 +0100

    crc32: Impl. linux optimized crc32()
    
    Ported over the more efficient linux crc32() function.
    A quick comparsion on ppc:
    After changing the old crc32 to do 4 bytes in the
    inner loop to be able to compare with new version one can note:
    - old inner loop has 61 insn, new has 19 insn.
    - new crc32 does one 32 bit load of data to crc while
      the old does four 8 bits loads.
    - size is bit bigger for the new crc32:
      1392(old) 1416(new) of text. The is because the new version
      shares code with crc32_no_comp() instead of duplicating code.
    - about 33% faster on ppc:
      New > crc 0 0xfffffff -> 39 secs
      Old > crc 0 0xfffffff -> 60 secs
    
    Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund at transmode.se>


Looks as if this were your very own commit. Do you have a fix in the
works?

Best regards,

Wolfgang Denk

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