Re: [PATCH v4 1/3] target-arm: Add support for Fujitsu A64FX

[Andrew Jones <drjones@redhat.com>]

On Thu, Aug 12, 2021 at 11:16:50AM +0200, Andrew Jones wrote:
> On Thu, Aug 12, 2021 at 03:04:38PM +0900, Shuuichirou Ishii wrote:
> > Add a definition for the Fujitsu A64FX processor.
> > 
> > The A64FX processor does not implement the AArch32 Execution state,
> > so there are no associated AArch32 Identification registers.
> > 
> > For SVE, the A64FX processor supports only 128,256 and 512bit vector lengths.
> > 
> > Signed-off-by: Shuuichirou Ishii <ishii.shuuichir@fujitsu.com>
> > ---
> >  target/arm/cpu.c   | 27 +++++++++++++++++++++++----
> >  target/arm/cpu.h   |  1 +
> >  target/arm/cpu64.c | 42 ++++++++++++++++++++++++++++++++++++++++++
> >  3 files changed, 66 insertions(+), 4 deletions(-)
> > 
> > diff --git a/target/arm/cpu.c b/target/arm/cpu.c
> > index 2866dd7658..162e46afc3 100644
> > --- a/target/arm/cpu.c
> > +++ b/target/arm/cpu.c
> > @@ -1345,15 +1345,34 @@ static void arm_cpu_finalizefn(Object *obj)
> >  #endif
> >  }
> >  
> > +static void a64fx_cpu_set_sve(ARMCPU *cpu)
> > +{
> > +    /* Suppport of A64FX's vector length are 128,256 and 512bit only */
> > +    bitmap_zero(cpu->sve_vq_map, ARM_MAX_VQ);
> > +    bitmap_zero(cpu->sve_vq_init, ARM_MAX_VQ);
> > +    set_bit(0, cpu->sve_vq_map); /* 128bit */
> > +    set_bit(0, cpu->sve_vq_init);
> > +    set_bit(1, cpu->sve_vq_map); /* 256bit */
> > +    set_bit(1, cpu->sve_vq_init);
> > +    set_bit(3, cpu->sve_vq_map); /* 512bit */
> > +    set_bit(3, cpu->sve_vq_init);
> > +
> > +    cpu->sve_max_vq = find_last_bit(cpu->sve_vq_map, ARM_MAX_VQ) + 1;
> > +}
> > +
> >  void arm_cpu_finalize_features(ARMCPU *cpu, Error **errp)
> >  {
> >      Error *local_err = NULL;
> >  
> >      if (arm_feature(&cpu->env, ARM_FEATURE_AARCH64)) {
> > -        arm_cpu_sve_finalize(cpu, &local_err);
> > -        if (local_err != NULL) {
> > -            error_propagate(errp, local_err);
> > -            return;
> > +        if (arm_feature(&cpu->env, ARM_FEATURE_A64FX)) {
> > +            a64fx_cpu_set_sve(cpu);
> > +        } else {
> > +            arm_cpu_sve_finalize(cpu, &local_err);
> > +            if (local_err != NULL) {
> > +                error_propagate(errp, local_err);
> > +                return;
> > +            }
> >          }
> >  
> >          /*
> > diff --git a/target/arm/cpu.h b/target/arm/cpu.h
> > index 9f0a5f84d5..84ebca731a 100644
> > --- a/target/arm/cpu.h
> > +++ b/target/arm/cpu.h
> > @@ -2145,6 +2145,7 @@ enum arm_features {
> >      ARM_FEATURE_M_SECURITY, /* M profile Security Extension */
> >      ARM_FEATURE_M_MAIN, /* M profile Main Extension */
> >      ARM_FEATURE_V8_1M, /* M profile extras only in v8.1M and later */
> > +    ARM_FEATURE_A64FX, /* Fujitsu A64FX processor */
> >  };
> >  
> >  static inline int arm_feature(CPUARMState *env, int feature)
> > diff --git a/target/arm/cpu64.c b/target/arm/cpu64.c
> > index c690318a9b..5e7e885f9d 100644
> > --- a/target/arm/cpu64.c
> > +++ b/target/arm/cpu64.c
> > @@ -847,10 +847,52 @@ static void aarch64_max_initfn(Object *obj)
> >                          cpu_max_set_sve_max_vq, NULL, NULL);
> >  }
> >  
> > +static void aarch64_a64fx_initfn(Object *obj)
> > +{
> > +    ARMCPU *cpu = ARM_CPU(obj);
> > +
> > +    cpu->dtb_compatible = "arm,a64fx";
> > +    set_feature(&cpu->env, ARM_FEATURE_A64FX);
> > +    set_feature(&cpu->env, ARM_FEATURE_V8);
> > +    set_feature(&cpu->env, ARM_FEATURE_NEON);
> > +    set_feature(&cpu->env, ARM_FEATURE_GENERIC_TIMER);
> > +    set_feature(&cpu->env, ARM_FEATURE_AARCH64);
> > +    set_feature(&cpu->env, ARM_FEATURE_EL2);
> > +    set_feature(&cpu->env, ARM_FEATURE_EL3);
> > +    set_feature(&cpu->env, ARM_FEATURE_PMU);
> > +    cpu->midr = 0x461f0010;
> > +    cpu->revidr = 0x00000000;
> > +    cpu->ctr = 0x86668006;
> > +    cpu->reset_sctlr = 0x30000180;
> > +    cpu->isar.id_aa64pfr0 =   0x0000000101111111; /* No RAS Extensions */
> > +    cpu->isar.id_aa64pfr1 = 0x0000000000000000;
> > +    cpu->isar.id_aa64dfr0 = 0x0000000010305408;
> > +    cpu->isar.id_aa64dfr1 = 0x0000000000000000;
> > +    cpu->id_aa64afr0 = 0x0000000000000000;
> > +    cpu->id_aa64afr1 = 0x0000000000000000;
> > +    cpu->isar.id_aa64mmfr0 = 0x0000000000001122;
> > +    cpu->isar.id_aa64mmfr1 = 0x0000000011212100;
> > +    cpu->isar.id_aa64mmfr2 = 0x0000000000001011;
> > +    cpu->isar.id_aa64isar0 = 0x0000000010211120;
> > +    cpu->isar.id_aa64isar1 = 0x0000000000010001;
> > +    cpu->isar.id_aa64zfr0 = 0x0000000000000000;
> > +    cpu->clidr = 0x0000000080000023;
> > +    cpu->ccsidr[0] = 0x7007e01c; /* 64KB L1 dcache */
> > +    cpu->ccsidr[1] = 0x2007e01c; /* 64KB L1 icache */
> > +    cpu->ccsidr[2] = 0x70ffe07c; /* 8MB L2 cache */
> > +    cpu->dcz_blocksize = 6; /* 256 bytes */
> > +    cpu->gic_num_lrs = 4;
> > +    cpu->gic_vpribits = 5;
> > +    cpu->gic_vprebits = 5;
> > +
> > +    /* TODO:  Add A64FX specific HPC extension registers */
> > +}
> > +
> >  static const ARMCPUInfo aarch64_cpus[] = {
> >      { .name = "cortex-a57",         .initfn = aarch64_a57_initfn },
> >      { .name = "cortex-a53",         .initfn = aarch64_a53_initfn },
> >      { .name = "cortex-a72",         .initfn = aarch64_a72_initfn },
> > +    { .name = "a64fx",              .initfn = aarch64_a64fx_initfn },
> >      { .name = "max",                .initfn = aarch64_max_initfn },
> >  };
> >  
> > -- 
> > 2.27.0
> >
> 
> For the SVE related bits
> 
> Reviewed-by: Andrew Jones <drjones@redhat.com>

On second thought, do we want the QMP CPU model expansion query to show
that this CPU type has sve,sve128,sve256,sve512? If so, then our SVE work
isn't complete, because we need those properties, set true by default, but
forbidden from changing.

Thanks,
drew