Re: [PATCH v4 22/40] target/arm: Update aa64_zva_access for EL2

[Alex Bennée]

Richard Henderson <address@hidden> writes:

> The comment that we don't support EL2 is somewhat out of date.
> Update to include checks against HCR_EL2.TDZ.
>
> Signed-off-by: Richard Henderson <address@hidden>

Reviewed-by: Alex Bennée <address@hidden>

> ---
>  target/arm/helper.c | 26 +++++++++++++++++++++-----
>  1 file changed, 21 insertions(+), 5 deletions(-)
>
> diff --git a/target/arm/helper.c b/target/arm/helper.c
> index 4f5e0b656c..ffa82b5509 100644
> --- a/target/arm/helper.c
> +++ b/target/arm/helper.c
> @@ -4109,11 +4109,27 @@ static void tlbi_aa64_ipas2e1is_write(CPUARMState 
> *env, const ARMCPRegInfo *ri,
>  static CPAccessResult aa64_zva_access(CPUARMState *env, const ARMCPRegInfo 
> *ri,
>                                        bool isread)
>  {
> -    /* We don't implement EL2, so the only control on DC ZVA is the
> -     * bit in the SCTLR which can prohibit access for EL0.
> -     */
> -    if (arm_current_el(env) == 0 && !(env->cp15.sctlr_el[1] & SCTLR_DZE)) {
> -        return CP_ACCESS_TRAP;
> +    int cur_el = arm_current_el(env);
> +
> +    if (cur_el < 2) {
> +        uint64_t hcr = arm_hcr_el2_eff(env);
> +
> +        if (cur_el == 0) {
> +            if ((hcr & (HCR_E2H | HCR_TGE)) == (HCR_E2H | HCR_TGE)) {
> +                if (!(env->cp15.sctlr_el[2] & SCTLR_DZE)) {
> +                    return CP_ACCESS_TRAP_EL2;
> +                }
> +            } else {
> +                if (!(env->cp15.sctlr_el[1] & SCTLR_DZE)) {
> +                    return CP_ACCESS_TRAP;
> +                }
> +                if (hcr & HCR_TDZ) {
> +                    return CP_ACCESS_TRAP_EL2;
> +                }
> +            }
> +        } else if (hcr & HCR_TDZ) {
> +            return CP_ACCESS_TRAP_EL2;
> +        }
>      }
>      return CP_ACCESS_OK;
>  }


-- 
Alex Bennée