Re: [PATCH 27/71] target/arm: Add SMIDR_EL1, SMPRI_EL1, SMPRIMAP_EL2

[Peter Maydell]

On Thu, 2 Jun 2022 at 23:28, Richard Henderson
<richard.henderson@linaro.org> wrote:
>
> Implement the streaming mode identification register, and the
> two streaming priority registers.  For QEMU, they are all RES0.
>
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
> ---
>  target/arm/helper.c | 33 +++++++++++++++++++++++++++++++++
>  1 file changed, 33 insertions(+)
>
> diff --git a/target/arm/helper.c b/target/arm/helper.c
> index 4149570b95..f852fd7644 100644
> --- a/target/arm/helper.c
> +++ b/target/arm/helper.c
> @@ -6355,6 +6355,18 @@ static CPAccessResult access_tpidr2(CPUARMState *env, 
> const ARMCPRegInfo *ri,
>      return CP_ACCESS_OK;
>  }
>
> +static CPAccessResult access_esm(CPUARMState *env, const ARMCPRegInfo *ri,
> +                                 bool isread)
> +{
> +    /* TODO: FEAT_FGT for SMPRI_EL1 but not SMPRIMAP_EL2 */
> +    if (arm_current_el(env) < 3
> +        && arm_feature(env, ARM_FEATURE_EL3)
> +        && !FIELD_EX64(env->cp15.cptr_el[3], CPTR_EL3, ESM)) {
> +        return CP_ACCESS_TRAP_EL3;
> +    }
> +    return CP_ACCESS_OK;
> +}
> +
>  static void svcr_write(CPUARMState *env, const ARMCPRegInfo *ri,
>                         uint64_t value)
>  {
> @@ -6412,6 +6424,27 @@ static const ARMCPRegInfo sme_reginfo[] = {
>        .access = PL3_RW, .type = ARM_CP_SME,
>        .fieldoffset = offsetof(CPUARMState, vfp.smcr_el[3]),
>        .writefn = smcr_write, .raw_writefn = raw_write },
> +    { .name = "SMIDR_EL1", .state = ARM_CP_STATE_AA64,
> +      .opc0 = 3, .opc1 = 1, .crn = 0, .crm = 0, .opc2 = 6,
> +      .access = PL1_RW, .accessfn = access_aa64_tid1,

Shouldn't this be PL1_R, not _RW ?

> +      /*
> +       * IMPLEMENTOR = 0 (software)
> +       * REVISION    = 0 (implementation defined)
> +       * SMPS        = 0 (no streaming execution priority in QEMU)
> +       * AFFINITY    = 0 (streaming sve mode not shared with other PEs)
> +       */
> +      .type = ARM_CP_CONST, .resetvalue = 0, },
> +    /*
> +     * Because SMIDR_EL1.SMPS is 0, SMPRI_EL1 and SMPRIMAP_EL2 are RES 0.
> +     */
> +    { .name = "SMPRI_EL1", .state = ARM_CP_STATE_AA64,
> +      .opc0 = 3, .opc1 = 0, .crn = 1, .crm = 2, .opc2 = 4,
> +      .access = PL1_RW, .accessfn = access_esm,
> +      .type = ARM_CP_CONST, .resetvalue = 0 },
> +    { .name = "SMPRIMAP_EL2", .state = ARM_CP_STATE_AA64,
> +      .opc0 = 3, .opc1 = 4, .crn = 1, .crm = 2, .opc2 = 5,
> +      .access = PL2_RW, .accessfn = access_esm,
> +      .type = ARM_CP_CONST, .resetvalue = 0 },
>  };
>  #endif /* TARGET_AARCH64 */

Otherwise
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>

thanks
-- PMM