| Message ID | BANLkTi=Bv=+6QgcHC0=jGiRFOc3D3ug2JA@mail.gmail.com |
|---|---|
| State | New |
| Headers | show |
On Tue, May 17, 2011 at 6:32 PM, Julien Grall <julien.grall@gmail.com> wrote: > Fix TA0_SHUTDOWN feature But what would be the bug? > Signed-off-by: Julien Grall <julien.grall@gmail.com> > --- > target-sparc/op_helper.c | 13 +++++++++++-- > target-sparc/translate.c | 9 +-------- > 2 files changed, 12 insertions(+), 10 deletions(-) > > diff --git a/target-sparc/op_helper.c b/target-sparc/op_helper.c > index a6fabad..cb775f5 100644 > --- a/target-sparc/op_helper.c > +++ b/target-sparc/op_helper.c > @@ -326,8 +326,17 @@ void HELPER(raise_exception)(int tt) > > void HELPER(trap_always)(int tt) > { > - env->exception_index = tt; > - do_interrupt(env); > + if (tt == TT_TRAP > + && env->def->features & CPU_FEATURE_TA0_SHUTDOWN > +#ifndef TARGET_SPARC64 > + && env->psret == 0 > +#endif > + ) { > + helper_shutdown(); > + } else { > + env->exception_index = tt; > + do_interrupt(env); > + } > } > > void helper_shutdown(void) > diff --git a/target-sparc/translate.c b/target-sparc/translate.c > index b30003b..a47a2de 100644 > --- a/target-sparc/translate.c > +++ b/target-sparc/translate.c > @@ -2009,14 +2009,7 @@ static void disas_sparc_insn(DisasContext * dc) > tcg_gen_addi_tl(cpu_dst, cpu_dst, TT_TRAP); > tcg_gen_trunc_tl_i32(cpu_tmp32, cpu_dst); > > - if (rs2 == 0 && > - dc->def->features & CPU_FEATURE_TA0_SHUTDOWN) { > - > - gen_helper_shutdown(); > - > - } else { > - gen_helper_trap_always(cpu_tmp32); > - } > + gen_helper_trap_always(cpu_tmp32); No, this would actually be just opposite to how QEMU works. Performance comes from doing more work at translation time in order to save time during executing the generated code.
On Tue, May 17, 2011 at 9:57 PM, Blue Swirl <blauwirbel@gmail.com> wrote: > On Tue, May 17, 2011 at 6:32 PM, Julien Grall <julien.grall@gmail.com> wrote: >> Fix TA0_SHUTDOWN feature > > But what would be the bug? We try to add RTEMS's support on leon platform for QEMU. RTEMS uses software trap 0 for various syscall. The current implementation of TA0_SHUTDOWN breaks the RTEMS boot. > No, this would actually be just opposite to how QEMU works. > Performance comes from doing more work at translation time in order to > save time during executing the generated code. I agree, this solution slows down the execution, but I didn't find another solution to fix this bug.
On Wed, May 18, 2011 at 4:17 PM, Julien Grall <julien.grall@gmail.com> wrote: > On Tue, May 17, 2011 at 9:57 PM, Blue Swirl <blauwirbel@gmail.com> wrote: >> On Tue, May 17, 2011 at 6:32 PM, Julien Grall <julien.grall@gmail.com> wrote: >>> Fix TA0_SHUTDOWN feature >> >> But what would be the bug? > > We try to add RTEMS's support on leon platform for QEMU. RTEMS uses > software trap 0 for various syscall. > The current implementation of TA0_SHUTDOWN breaks the RTEMS boot. > >> No, this would actually be just opposite to how QEMU works. >> Performance comes from doing more work at translation time in order to >> save time during executing the generated code. > > I agree, this solution slows down the execution, but I didn't find > another solution to fix this bug. You should retain the feature check in translate.c but add a leon specific helper in place of helper_shutdown, which can check for psret. It would be also possible to generate code for the psret check if the helper overhead were an issue.
diff --git a/target-sparc/op_helper.c b/target-sparc/op_helper.c index a6fabad..cb775f5 100644 --- a/target-sparc/op_helper.c +++ b/target-sparc/op_helper.c @@ -326,8 +326,17 @@ void HELPER(raise_exception)(int tt) void HELPER(trap_always)(int tt) { - env->exception_index = tt; - do_interrupt(env); + if (tt == TT_TRAP + && env->def->features & CPU_FEATURE_TA0_SHUTDOWN +#ifndef TARGET_SPARC64 + && env->psret == 0 +#endif + ) { + helper_shutdown(); + } else { + env->exception_index = tt; + do_interrupt(env); + } } void helper_shutdown(void) diff --git a/target-sparc/translate.c b/target-sparc/translate.c index b30003b..a47a2de 100644 --- a/target-sparc/translate.c +++ b/target-sparc/translate.c @@ -2009,14 +2009,7 @@ static void disas_sparc_insn(DisasContext * dc) tcg_gen_addi_tl(cpu_dst, cpu_dst, TT_TRAP); tcg_gen_trunc_tl_i32(cpu_tmp32, cpu_dst); - if (rs2 == 0 && - dc->def->features & CPU_FEATURE_TA0_SHUTDOWN) { - - gen_helper_shutdown(); - - } else { - gen_helper_trap_always(cpu_tmp32); - } + gen_helper_trap_always(cpu_tmp32); } else if (cond != 0) { TCGv r_cond = tcg_temp_new(); int l1;
Fix TA0_SHUTDOWN feature Signed-off-by: Julien Grall <julien.grall@gmail.com> --- target-sparc/op_helper.c | 13 +++++++++++-- target-sparc/translate.c | 9 +-------- 2 files changed, 12 insertions(+), 10 deletions(-)