Hi Kuan-Yu Kuo,

2013/7/18 Kuan-Yu Kuo <ken.ku...@gmail.com>:
> +       /*
> +        * enable_fpu:
> +        *  Some of Andes CPU version support FPU coprocessor, if so,
> +        *  we should enable it.
> +        */
> +enable_fpu:
> +       mfsr    $r0, $CPU_VER           /* enable FPU if it exists */
> +       srli    $r0, $r0, 3
> +       andi    $r0, $r0, 1
> +       beqz    $r0, 1f                                         /* skip if no 
> COP */
> +       mfsr    $r0, $FUCOP_EXIST
> +       srli    $r0, $r0, 31
> +       beqz    $r0, 1f                                         /* skip if no 
> FPU */
> +       mfsr    $r0, $FUCOP_CTL
> +       ori     $r0, $r0, 1
> +       mtsr    $r0, $FUCOP_CTL

There are two kinds of toolchain in Andes architecture, one is FPU supported 
and the other is not, for the latter one, there is no need to enable FPU even 
if the processor supports it.
This code snippet only useful for the toolchain that will generate FPU 
instructions, so add compile option to determine Andes predefined macros would 
be better.
For example:
#if defined(NDS32_EXT_FPU_DP) || defined(NDS32_EXT_FPU_SP)

Andes Technology Corporation
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