Re: [PATCH v2 5/5] target/arm: Add support for missing Jazelle system registers

[Edgar E. Iglesias]

On Sun, Dec 01, 2019 at 12:20:18PM +0000, Marc Zyngier wrote:
> QEMU lacks the minimum Jazelle implementation that is required
> by the architecture (everything is RAZ or RAZ/WI). Add it
> together with the HCR_EL2.TID0 trapping that goes with it.


Looks good to me:
Reviewed-by: Edgar E. Iglesias <address@hidden>


> 
> Signed-off-by: Marc Zyngier <address@hidden>
> ---
>  target/arm/helper.c | 27 +++++++++++++++++++++++++++
>  1 file changed, 27 insertions(+)
> 
> diff --git a/target/arm/helper.c b/target/arm/helper.c
> index 0ba08d550a..d6fc198a97 100644
> --- a/target/arm/helper.c
> +++ b/target/arm/helper.c
> @@ -6040,6 +6040,16 @@ static CPAccessResult access_aa32_tid3(CPUARMState 
> *env, const ARMCPRegInfo *ri,
>      return CP_ACCESS_OK;
>  }
>  
> +static CPAccessResult access_jazelle(CPUARMState *env, const ARMCPRegInfo 
> *ri,
> +                                     bool isread)
> +{
> +    if (arm_current_el(env) == 1 && (arm_hcr_el2_eff(env) & HCR_TID0)) {
> +        return CP_ACCESS_TRAP_EL2;
> +    }
> +
> +    return CP_ACCESS_OK;
> +}
> +
>  void register_cp_regs_for_features(ARMCPU *cpu)
>  {
>      /* Register all the coprocessor registers based on feature bits */
> @@ -6057,6 +6067,23 @@ void register_cp_regs_for_features(ARMCPU *cpu)
>          define_arm_cp_regs(cpu, not_v8_cp_reginfo);
>      }
>  
> +    if (cpu_isar_feature(jazelle, cpu)) {
> +        ARMCPRegInfo jazelle_regs[] = {
> +            { .name = "JIDR",
> +              .cp = 14, .crn = 0, .crm = 0, .opc1 = 7, .opc2 = 0,
> +              .access = PL1_R, .accessfn = access_jazelle,
> +              .type = ARM_CP_CONST, .resetvalue = 0 },
> +            { .name = "JOSCR",
> +              .cp = 14, .crn = 1, .crm = 0, .opc1 = 7, .opc2 = 0,
> +              .access = PL1_RW, .type = ARM_CP_CONST, .resetvalue = 0 },
> +            { .name = "JMCR",
> +              .cp = 14, .crn = 2, .crm = 0, .opc1 = 7, .opc2 = 0,
> +              .access = PL1_RW, .type = ARM_CP_CONST, .resetvalue = 0 },
> +            REGINFO_SENTINEL
> +        };
> +
> +        define_arm_cp_regs(cpu, jazelle_regs);
> +    }
>      if (arm_feature(env, ARM_FEATURE_V6)) {
>          /* The ID registers all have impdef reset values */
>          ARMCPRegInfo v6_idregs[] = {
> -- 
> 2.20.1
> 
>