Re: [PATCH 01/38] target/riscv: implementation-defined constant parameters

[Alistair Francis <alistair23@gmail.com>]

On Fri, Feb 12, 2021 at 10:05 AM LIU Zhiwei <zhiwei_liu@c-sky.com> wrote:
>
> ext_p64 is whether to support Zp64 extension in RV32, default value is true.
> pext_ver is the packed specification version, default value is v0.9.2.
>
> Signed-off-by: LIU Zhiwei <zhiwei_liu@c-sky.com>

Reviewed-by: Alistair Francis <alistair.francis@wdc.com>

Alistair

> ---
>  target/riscv/cpu.c       | 29 +++++++++++++++++++++++++++++
>  target/riscv/cpu.h       |  6 ++++++
>  target/riscv/translate.c |  2 ++
>  3 files changed, 37 insertions(+)
>
> diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
> index 16f1a34238..1b99f629ec 100644
> --- a/target/riscv/cpu.c
> +++ b/target/riscv/cpu.c
> @@ -132,6 +132,11 @@ static void set_vext_version(CPURISCVState *env, int vext_ver)
>      env->vext_ver = vext_ver;
>  }
>
> +static void set_pext_version(CPURISCVState *env, int pext_ver)
> +{
> +    env->pext_ver = pext_ver;
> +}
> +
>  static void set_feature(CPURISCVState *env, int feature)
>  {
>      env->features |= (1ULL << feature);
> @@ -380,6 +385,7 @@ static void riscv_cpu_realize(DeviceState *dev, Error **errp)
>      RISCVCPUClass *mcc = RISCV_CPU_GET_CLASS(dev);
>      int priv_version = PRIV_VERSION_1_11_0;
>      int vext_version = VEXT_VERSION_0_07_1;
> +    int pext_version = PEXT_VERSION_0_09_2;
>      target_ulong target_misa = env->misa;
>      Error *local_err = NULL;
>
> @@ -404,6 +410,7 @@ static void riscv_cpu_realize(DeviceState *dev, Error **errp)
>
>      set_priv_version(env, priv_version);
>      set_vext_version(env, vext_version);
> +    set_pext_version(env, pext_version);
>
>      if (cpu->cfg.mmu) {
>          set_feature(env, RISCV_FEATURE_MMU);
> @@ -511,6 +518,28 @@ static void riscv_cpu_realize(DeviceState *dev, Error **errp)
>              }
>              set_vext_version(env, vext_version);
>          }
> +        if (cpu->cfg.ext_p) {
> +            target_misa |= RVP;
> +            if (cpu->cfg.pext_spec) {
> +                if (!g_strcmp0(cpu->cfg.pext_spec, "v0.9.2")) {
> +                    pext_version = PEXT_VERSION_0_09_2;
> +                } else {
> +                    error_setg(errp,
> +                               "Unsupported packed spec version '%s'",
> +                               cpu->cfg.pext_spec);
> +                    return;
> +                }
> +            } else {
> +                qemu_log("packed verison is not specified, "
> +                         "use the default value v0.9.2\n");
> +            }
> +            if (!cpu->cfg.ext_p64 && env->misa == RV64) {
> +                error_setg(errp, "For RV64, the Zp64 instructions will be "
> +                                 "included in the baseline P extension.");
> +                return;
> +            }
> +            set_pext_version(env, pext_version);
> +        }
>
>          set_misa(env, target_misa);
>      }
> diff --git a/target/riscv/cpu.h b/target/riscv/cpu.h
> index 02758ae0eb..f458722646 100644
> --- a/target/riscv/cpu.h
> +++ b/target/riscv/cpu.h
> @@ -68,6 +68,7 @@
>  #define RVF RV('F')
>  #define RVD RV('D')
>  #define RVV RV('V')
> +#define RVP RV('P')
>  #define RVC RV('C')
>  #define RVS RV('S')
>  #define RVU RV('U')
> @@ -87,6 +88,7 @@ enum {
>  #define PRIV_VERSION_1_11_0 0x00011100
>
>  #define VEXT_VERSION_0_07_1 0x00000701
> +#define PEXT_VERSION_0_09_2 0x00000902
>
>  enum {
>      TRANSLATE_SUCCESS,
> @@ -134,6 +136,7 @@ struct CPURISCVState {
>
>      target_ulong priv_ver;
>      target_ulong vext_ver;
> +    target_ulong pext_ver;
>      target_ulong misa;
>      target_ulong misa_mask;
>
> @@ -288,13 +291,16 @@ struct RISCVCPU {
>          bool ext_u;
>          bool ext_h;
>          bool ext_v;
> +        bool ext_p;
>          bool ext_counters;
>          bool ext_ifencei;
>          bool ext_icsr;
> +        bool ext_p64;
>
>          char *priv_spec;
>          char *user_spec;
>          char *vext_spec;
> +        char *pext_spec;
>          uint16_t vlen;
>          uint16_t elen;
>          bool mmu;
> diff --git a/target/riscv/translate.c b/target/riscv/translate.c
> index 0f28b5f41e..eb810efec6 100644
> --- a/target/riscv/translate.c
> +++ b/target/riscv/translate.c
> @@ -56,6 +56,7 @@ typedef struct DisasContext {
>         to reset this known value.  */
>      int frm;
>      bool ext_ifencei;
> +    bool ext_p64;
>      bool hlsx;
>      /* vector extension */
>      bool vill;
> @@ -824,6 +825,7 @@ static void riscv_tr_init_disas_context(DisasContextBase *dcbase, CPUState *cs)
>      ctx->lmul = FIELD_EX32(tb_flags, TB_FLAGS, LMUL);
>      ctx->mlen = 1 << (ctx->sew  + 3 - ctx->lmul);
>      ctx->vl_eq_vlmax = FIELD_EX32(tb_flags, TB_FLAGS, VL_EQ_VLMAX);
> +    ctx->ext_p64 = cpu->cfg.ext_p64;
>      ctx->cs = cs;
>  }
>
> --
> 2.17.1
>