Re: [PATCH 2/5] MIPS: Add instrunction format for BREAK and SYSCALL

Maciej W. Rozycki
2010-08-03T20:54:41Z

On Tue, 3 Aug 2010, David Daney wrote:

> diff --git a/arch/mips/include/asm/inst.h b/arch/mips/include/asm/inst.h
> index 6489f00..444ff71 100644
> --- a/arch/mips/include/asm/inst.h
> +++ b/arch/mips/include/asm/inst.h
> @@ -247,6 +247,12 @@ struct ma_format { /* FPU multipy and add format (MIPS IV) */
> unsigned int fmt : 2;
> };
>
> +struct b_format { /* BREAK and SYSCALL */
> + unsigned int opcode:6;
> + unsigned int code:20;
> + unsigned int func:6;
> +};
> +
> #elif defined(__MIPSEL__)
>
> struct j_format { /* Jump format */

Please note the code field of the BREAK instruction is by toolchain
convention (bug-compatibility with the original MIPS assembler or
suchlike) treated as a pair of swapped 10-bit fields -- you may want to
double-check consistency of interpretation with usage elsewhere.

Maciej