On 5/17/19 7:40 PM, Peter Maydell wrote:
> Allow the DSP extension to be disabled via a CPU property for
> M-profile CPUs. (A and R-profile CPUs don't have this extension
> as a defined separate optional architecture extension, so
> they don't need the property.)
>
> Signed-off-by: Peter Maydell <peter.mayd...@linaro.org>
> ---
> target/arm/cpu.h | 2 ++
> target/arm/cpu.c | 29 +++++++++++++++++++++++++++++
> 2 files changed, 31 insertions(+)
>
> diff --git a/target/arm/cpu.h b/target/arm/cpu.h
> index 778fb293e7c..b1c7ab3ee94 100644
> --- a/target/arm/cpu.h
> +++ b/target/arm/cpu.h
> @@ -801,6 +801,8 @@ struct ARMCPU {
> bool has_vfp;
> /* CPU has Neon */
> bool has_neon;
> + /* CPU has M-profile DSP extension */
> + bool has_dsp;
>
> /* CPU has memory protection unit */
> bool has_mpu;
> diff --git a/target/arm/cpu.c b/target/arm/cpu.c
> index 406fd360a2a..c43139ba897 100644
> --- a/target/arm/cpu.c
> +++ b/target/arm/cpu.c
> @@ -769,6 +769,9 @@ static Property arm_cpu_has_vfp_property =
> static Property arm_cpu_has_neon_property =
> DEFINE_PROP_BOOL("neon", ARMCPU, has_neon, true);
>
> +static Property arm_cpu_has_dsp_property =
> + DEFINE_PROP_BOOL("dsp", ARMCPU, has_dsp, true);
> +
> static Property arm_cpu_has_mpu_property =
> DEFINE_PROP_BOOL("has-mpu", ARMCPU, has_mpu, true);
>
> @@ -881,6 +884,12 @@ void arm_cpu_post_init(Object *obj)
> }
> }
>
> + if (arm_feature(&cpu->env, ARM_FEATURE_M) &&
> + arm_feature(&cpu->env, ARM_FEATURE_THUMB_DSP)) {
> + qdev_property_add_static(DEVICE(obj), &arm_cpu_has_dsp_property,
> + &error_abort);
TIL qdev_property_add_static, clean.
Reviewed-by: Philippe Mathieu-Daudé <phi...@redhat.com>
> + }
> +
> if (arm_feature(&cpu->env, ARM_FEATURE_PMSA)) {
> qdev_property_add_static(DEVICE(obj), &arm_cpu_has_mpu_property,
> &error_abort);
> @@ -1100,6 +1109,26 @@ static void arm_cpu_realizefn(DeviceState *dev, Error
> **errp)
> cpu->isar.mvfr0 = u;
> }
>
> + if (arm_feature(env, ARM_FEATURE_M) && !cpu->has_dsp) {
> + uint32_t u;
> +
> + unset_feature(env, ARM_FEATURE_THUMB_DSP);
> +
> + u = cpu->isar.id_isar1;
> + u = FIELD_DP32(u, ID_ISAR1, EXTEND, 1);
> + cpu->isar.id_isar1 = u;
> +
> + u = cpu->isar.id_isar2;
> + u = FIELD_DP32(u, ID_ISAR2, MULTU, 1);
> + u = FIELD_DP32(u, ID_ISAR2, MULTS, 1);
> + cpu->isar.id_isar2 = u;
> +
> + u = cpu->isar.id_isar3;
> + u = FIELD_DP32(u, ID_ISAR3, SIMD, 1);
> + u = FIELD_DP32(u, ID_ISAR3, SATURATE, 0);
> + cpu->isar.id_isar3 = u;
> + }
> +
> /* Some features automatically imply others: */
> if (arm_feature(env, ARM_FEATURE_V8)) {
> if (arm_feature(env, ARM_FEATURE_M)) {
>
