[linux-yocto] [PATCH 3.14] mips: octeon: use ll/sc for the atomic ops for all the predecessor of octeon2

[Bruce Ashfield]

On 15-08-31 07:34 AM, Kevin Hao wrote:
> Even the octeon plus has the support of the 'saa' instruction, but we
> don't have a way to distinguish between octeon and octeon plus at
> compile time and pass "-march=octeon" to all the predecessor of
> octeon2. So it will cause the following error when trying to assemble
> the "saa" instruction with option "-march=octeon":
>    {standard input}: Assembler messages:
>    {standard input}:360: Error: Unrecognized opcode `saa $2,($4)'
>    scripts/Makefile.build:308: recipe for target 'arch/mips/cavium-octeon/executive/cvmx-lap.o' failed
>
> Forcing to use the "ll/sc" for the atomic ops for all the predecessor
> of octeon2 to fix this issue.
>

Thanks Kevin,

My test builds have passed, so I've queued this and will send it out
shortly.

Bruce


> Signed-off-by: Kevin Hao <kexin.hao at windriver.com>
> ---
>   arch/mips/include/asm/octeon/cvmx-atomic.h | 6 +-----
>   1 file changed, 1 insertion(+), 5 deletions(-)
>
> diff --git a/arch/mips/include/asm/octeon/cvmx-atomic.h b/arch/mips/include/asm/octeon/cvmx-atomic.h
> index f4bfb7598634..b2b06438c24f 100644
> --- a/arch/mips/include/asm/octeon/cvmx-atomic.h
> +++ b/arch/mips/include/asm/octeon/cvmx-atomic.h
> @@ -79,7 +79,7 @@ static inline void cvmx_atomic_add32_nosync(int32_t * ptr, int32_t incr)
>   				     :"memory");
>   	}
>   #else
> -	if (OCTEON_IS_MODEL(OCTEON_CN3XXX)) {
> +	{
>   		uint32_t tmp;
>
>   		__asm__ __volatile__(".set noreorder         \n"
> @@ -89,10 +89,6 @@ static inline void cvmx_atomic_add32_nosync(int32_t * ptr, int32_t incr)
>   				     "   beqz %[tmp], 1b     \n" "   nop                 \n" ".set reorder           \n":[val] "+m"(*ptr),[tmp] "=&r"(tmp)
>   				     :[inc] "r"(incr)
>   				     :"memory");
> -	} else {
> -		__asm__ __volatile__("   saa %[inc], (%[base]) \n":"+m"(*ptr)
> -				     :[inc] "r"(incr),[base] "r"(ptr)
> -				     :"memory");
>   	}
>   #endif
>   }
>