Re: [PATCH] linux-user/mips: Low down switchable NaN2008 requirement

[Laurent Vivier <laurent@vivier.eu>]

Phil (or someone else that knows mips), could you review?

With one review I will apply to my linux-user branch.

Thanks,
Laurent

Le 22/02/2023 à 11:28, Jiaxun Yang a écrit :
> Ping？
> 
>> 2023年2月11日 17:34，Jiaxun Yang <jiaxun.yang@flygoat.com> 写道：
>>
>> Previously switchable NaN2008 requires fcsr31.nan2008 to be writable
>> for guest. However as per MIPS arch spec this bit can never be writable.
>> This cause NaN2008 ELF to be rejected by QEMU.
>>
>> NaN2008 can be enabled on R2~R5 processors, just make it available
>> unconditionally.
>>
>> Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
>> ---
>> linux-user/mips/cpu_loop.c | 3 +--
>> 1 file changed, 1 insertion(+), 2 deletions(-)
>>
>> diff --git a/linux-user/mips/cpu_loop.c b/linux-user/mips/cpu_loop.c
>> index d5c1c7941d..b5c2ca4a3e 100644
>> --- a/linux-user/mips/cpu_loop.c
>> +++ b/linux-user/mips/cpu_loop.c
>> @@ -301,8 +301,7 @@ void target_cpu_copy_regs(CPUArchState *env, struct target_pt_regs *regs)
>>      }
>>      if (((info->elf_flags & EF_MIPS_NAN2008) != 0) !=
>>          ((env->active_fpu.fcr31 & (1 << FCR31_NAN2008)) != 0)) {
>> -        if ((env->active_fpu.fcr31_rw_bitmask &
>> -              (1 << FCR31_NAN2008)) == 0) {
>> +        if (!(env->insn_flags & ISA_MIPS_R2)) {
>>              fprintf(stderr, "ELF binary's NaN mode not supported by CPU\n");
>>              exit(1);
>>          }
>> -- 
>> 2.37.1 (Apple Git-137.1)
>>
> 
>