[PATCH 2/2] selftests/powerpc: Add a test of the switch_endian() syscall

[Ram Pai]

On Fri, Mar 13, 2015 at 03:39:24PM +1100, Michael Ellerman wrote:
> This adds a test of the switch_endian() syscall we added in the previous
> commit.
> 
> We test it by calling the endian switch syscall, and then executing some
> code in the other endian to check everything went as expected. That code
> checks registers we expect to be maintained are, and then writes to
> stdout and then does exit(0).
> 
> If the endian switch failed to happen that code sequence will be illegal
> and cause the test to abort.
> 
> Signed-off-by: Michael Ellerman <mpe at ellerman.id.au>
> ---
..snip..
> +	.long 0x04000038
> +	# li      r3,1
> +	.long 0x01006038
> +	# mr      r4,r14
> +	.long 0x7873c47d
> +	# li      r5,21
> +	.long 0x1500a038
> +	# sc
> +	.long 0x02000044
> +	# li      r3,0
> +	.long 0x00006038
> +	# 1:
> +	# li      r0, __NR_exit

Would it make sense to toggle the endianness here,
checking for the same register sanity before exiting?

That way endian switching is tested both ways?

RP