Re: [PATCH 01/14] target/arm: add arm_is_el2_enabled() helper

[Peter Maydell]

On Mon, 2 Nov 2020 at 10:58, <remi.denis.courmont@huawei.com> wrote:
>
> From: Rémi Denis-Courmont <remi.denis.courmont@huawei.com>
>
> This checks if EL2 is enabled (meaning EL2 registers take effects) in
> the current security context.
>
> Signed-off-by: Rémi Denis-Courmont <remi.denis.courmont@huawei.com>
> ---
>  target/arm/cpu.h | 14 ++++++++++++++
>  1 file changed, 14 insertions(+)
>
> diff --git a/target/arm/cpu.h b/target/arm/cpu.h
> index c18a916766..aaf3671806 100644
> --- a/target/arm/cpu.h
> +++ b/target/arm/cpu.h
> @@ -2040,6 +2040,15 @@ static inline bool arm_is_secure(CPUARMState *env)
>      return arm_is_secure_below_el3(env);
>  }
>
> +/* Return true if the current security state has AArch64 EL2 or AArch32 Hyp 
> */
> +static inline bool arm_is_el2_enabled(CPUARMState *env)
> +{
> +    if (arm_feature(env, ARM_FEATURE_EL2)) {
> +        return !arm_is_secure_below_el3(env);
> +    }
> +    return false;

You could usefully add a comment mentioning the EL2Enabled()
pseudocode and that we'll need to adjust this if we implement
Secure EL2 in future.

thanks
-- PMM