Re: [Qemu-devel] [PATCH 1/2] target-ppc: Change default cpu for ppc64le-linux-user

[Alexander Graf]

> Am 28.06.2014 um 18:45 schrieb Richard Henderson <address@hidden>:
> 
> The default, 970fx, doesn't support MSR_LE.  So even though we set LE in
> ppc_cpu_reset, it gets cleared again in hreg_store_msr.  Error out if a
> user-selected cpu model doesn't support LE.
> 
> Cc: Aldy Hernandez <address@hidden>
> Signed-off-by: Richard Henderson <address@hidden>
> ---
> The warning one gets from the unimplemented insns from tcg
> is perhaps unfortunate, but it's better than silently dropping
> the MSR_LE bit and interpreting the first few insns with the
> wrong endianness and generating SIGILL.
> 
> One could, perhaps, simply return false from need_byteswap.
> But then the value of MSR would still be wrong, and I can imagine
> that would affect gdb's interpretation of the current mode.
> 
> 
> r~
> ---
> linux-user/main.c           | 10 +++++++---
> target-ppc/translate_init.c |  4 ++++
> 2 files changed, 11 insertions(+), 3 deletions(-)
> 
> diff --git a/linux-user/main.c b/linux-user/main.c
> index 900a17f..058b08c 100644
> --- a/linux-user/main.c
> +++ b/linux-user/main.c
> @@ -3901,11 +3901,15 @@ int main(int argc, char **argv, char **envp)
> #elif defined TARGET_OPENRISC
>         cpu_model = "or1200";
> #elif defined(TARGET_PPC)
> -#ifdef TARGET_PPC64
> +# ifdef TARGET_PPC64
> +#  ifdef TARGET_WORDS_BIGENDIAN
>         cpu_model = "970fx";
> -#else
> +#  else
> +        cpu_model = "POWER7";

How about we switch to p7 for BE top?

Alex

> +#  endif
> +# else
>         cpu_model = "750";
> -#endif
> +# endif
> #else
>         cpu_model = "any";
> #endif
> diff --git a/target-ppc/translate_init.c b/target-ppc/translate_init.c
> index 85581c9..72128d8 100644
> --- a/target-ppc/translate_init.c
> +++ b/target-ppc/translate_init.c
> @@ -9538,6 +9538,10 @@ static void ppc_cpu_reset(CPUState *s)
> #endif
> #if !defined(TARGET_WORDS_BIGENDIAN)
>     msr |= (target_ulong)1 << MSR_LE; /* Little-endian user mode */
> +    if (!((env->msr_mask >> MSR_LE) & 1)) {
> +        fprintf(stderr, "Selected CPU does not support little-endian.\n");
> +        exit(1);
> +    }
> #endif
> #endif
> 
> -- 
> 1.9.3
>