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

[Laurent Vivier]

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)