Re: [Qemu-devel] [PATCH v2 11/16] target/arm: Add SVE to migration state

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

Richard Henderson <richard.henderson@linaro.org> writes:

> Save the high parts of the Zregs and all of the Pregs.
> The ZCR_ELx registers are migrated via the CP mechanism.
>
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
> ---
>  target/arm/machine.c | 53 ++++++++++++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 53 insertions(+)
>
> diff --git a/target/arm/machine.c b/target/arm/machine.c
> index cb0e1c92bb..2c8b43062f 100644
> --- a/target/arm/machine.c
> +++ b/target/arm/machine.c
> @@ -122,6 +122,56 @@ static const VMStateDescription vmstate_iwmmxt = {
>      }
>  };
>
> +#ifdef TARGET_AARCH64
> +/* The expression ARM_MAX_VQ - 2 is 0 for pure AArch32 build,
> + * and ARMPredicateReg is actively empty.  This triggers errors
> + * in the expansion of the VMSTATE macros.
> + */

This makes me think that #ifdef-ing out the pregs might be better for
the 32 bit target build.

> +
> +static bool sve_needed(void *opaque)
> +{
> +    ARMCPU *cpu = opaque;
> +    CPUARMState *env = &cpu->env;
> +
> +    return arm_feature(env, ARM_FEATURE_SVE);
> +}
> +
> +/* The first two words of each Zreg is stored in VFP state.  */
> +static const VMStateDescription vmstate_zreg_hi_reg = {
> +    .name = "cpu/sve/zreg_hi",
> +    .version_id = 1,
> +    .minimum_version_id = 1,
> +    .fields = (VMStateField[]) {
> +        VMSTATE_UINT64_SUB_ARRAY(d, ARMVectorReg, 2, ARM_MAX_VQ - 2),
> +        VMSTATE_END_OF_LIST()
> +    }
> +};
> +
> +static const VMStateDescription vmstate_preg_reg = {
> +    .name = "cpu/sve/preg",
> +    .version_id = 1,
> +    .minimum_version_id = 1,
> +    .fields = (VMStateField[]) {
> +        VMSTATE_UINT64_ARRAY(p, ARMPredicateReg, 2 * ARM_MAX_VQ / 8),
> +        VMSTATE_END_OF_LIST()
> +    }
> +};
> +
> +static const VMStateDescription vmstate_sve = {
> +    .name = "cpu/sve",
> +    .version_id = 1,
> +    .minimum_version_id = 1,
> +    .needed = sve_needed,
> +    .fields = (VMStateField[]) {
> +        VMSTATE_STRUCT_ARRAY(env.vfp.zregs, ARMCPU, 32, 0,
> +                             vmstate_zreg_hi_reg, ARMVectorReg),
> +        VMSTATE_STRUCT_ARRAY(env.vfp.pregs, ARMCPU, 17, 0,
> +                             vmstate_preg_reg, ARMPredicateReg),
> +        VMSTATE_END_OF_LIST()
> +    }
> +};
> +#endif /* AARCH64 */
> +
>  static bool m_needed(void *opaque)
>  {
>      ARMCPU *cpu = opaque;
> @@ -586,6 +636,9 @@ const VMStateDescription vmstate_arm_cpu = {
>          &vmstate_pmsav7,
>          &vmstate_pmsav8,
>          &vmstate_m_security,
> +#ifdef TARGET_AARCH64
> +        &vmstate_sve,
> +#endif
>          NULL
>      }
>  };


--
Alex Bennée