Re: [Qemu-devel] [Qemu-arm] [PATCH 2/2] target/arm: Fix ATS1Hx instructions

["Alex Bennée" <alex.bennee@linaro.org>]

Peter Maydell <peter.maydell@linaro.org> writes:

> ATS1HR and ATS1HW (which allow AArch32 EL2 to do address translations
> on the EL2 translation regime) were implemented in commit 14db7fe09a2c8.
> However, we got them wrong: these should do stage 1 address translations
> as defined for NS-EL2, which is ARMMMUIdx_S1E2. We were incorrectly
> making them perform stage 2 translations.
>
> A few years later in commit 1313e2d7e2cd we forgot entirely that
> we'd implemented ATS1Hx, and added a comment that ATS1Hx were
> "not supported yet". Remove the comment; there is no extra code
> needed to handle these operations in do_ats_write(), because
> arm_s1_regime_using_lpae_format() returns true for ARMMMUIdx_S1E2,
> which forces 64-bit PAR format.
>
> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>

> ---
>  target/arm/helper.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/target/arm/helper.c b/target/arm/helper.c
> index dc849b09893..903a832f1fa 100644
> --- a/target/arm/helper.c
> +++ b/target/arm/helper.c
> @@ -2316,7 +2316,7 @@ static uint64_t do_ats_write(CPUARMState *env, uint64_t value,
>           *
>           * (Note that HCR.DC makes HCR.VM behave as if it is 1.)
>           *
> -         * ATS1Hx always uses the 64bit format (not supported yet).
> +         * ATS1Hx always uses the 64bit format.
>           */
>          format64 = arm_s1_regime_using_lpae_format(env, mmu_idx);
>
> @@ -2441,7 +2441,7 @@ static void ats1h_write(CPUARMState *env, const ARMCPRegInfo *ri,
>      MMUAccessType access_type = ri->opc2 & 1 ? MMU_DATA_STORE : MMU_DATA_LOAD;
>      uint64_t par64;
>
> -    par64 = do_ats_write(env, value, access_type, ARMMMUIdx_S2NS);
> +    par64 = do_ats_write(env, value, access_type, ARMMMUIdx_S1E2);
>
>      A32_BANKED_CURRENT_REG_SET(env, par, par64);
>  }


--
Alex Bennée