U-Boot DIV64 Issue

I just made u-boot works with Ethernet and Flash access and try to boot the linux kernel. but there is an error exception.

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==> imi e8060000

# # Checking Image at e8060000 ....

Legacy image found

Image Name: test

Image Type: NIOS II Linux Kernel Image (uncompressed)

Data Size: 3371311 Bytes =

*** ERROR: unimplemented instruction @ c7fd5764# ## ERROR# ## Please reset board# ##

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after tracing the code, i found the error is caused by an 64bit-divide-64bit operation.

display_options.c in u-boot/lib/

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void print_size(unsigned long long size, const char *s)

{

unsigned long m = 0, n;

static const char names[] = {'E', 'P', 'T', 'G', 'M', 'K'};

unsigned long long d = 1ULL << (10 * ARRAY_SIZE(names));

char c = 0;

unsigned int i;

...

n = size / d; <=== error generated here

...

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Since there is no any warning/error message during u-boot compile.

Does anyone have any suggestion ?