Re: [PATCH v6 03/72] target/riscv: rvv-1.0: add mstatus VS field

[Alistair Francis]

On Tue, Jan 12, 2021 at 1:48 AM <frank.chang@sifive.com> wrote:
>
> From: LIU Zhiwei <zhiwei_liu@c-sky.com>
>
> Signed-off-by: LIU Zhiwei <zhiwei_liu@c-sky.com>
> Signed-off-by: Frank Chang <frank.chang@sifive.com>
> Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

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

Alistair

> ---
>  target/riscv/cpu.h        |  7 +++++++
>  target/riscv/cpu_bits.h   |  1 +
>  target/riscv/cpu_helper.c | 15 ++++++++++++++-
>  target/riscv/csr.c        | 25 ++++++++++++++++++++++++-
>  4 files changed, 46 insertions(+), 2 deletions(-)
>
> diff --git a/target/riscv/cpu.h b/target/riscv/cpu.h
> index b0281133e09..cd5c77114a4 100644
> --- a/target/riscv/cpu.h
> +++ b/target/riscv/cpu.h
> @@ -325,6 +325,7 @@ int riscv_cpu_gdb_read_register(CPUState *cpu, GByteArray 
> *buf, int reg);
>  int riscv_cpu_gdb_write_register(CPUState *cpu, uint8_t *buf, int reg);
>  bool riscv_cpu_exec_interrupt(CPUState *cs, int interrupt_request);
>  bool riscv_cpu_fp_enabled(CPURISCVState *env);
> +bool riscv_cpu_vector_enabled(CPURISCVState *env);
>  bool riscv_cpu_virt_enabled(CPURISCVState *env);
>  void riscv_cpu_set_virt_enabled(CPURISCVState *env, bool enable);
>  bool riscv_cpu_force_hs_excep_enabled(CPURISCVState *env);
> @@ -372,6 +373,7 @@ void riscv_cpu_set_fflags(CPURISCVState *env, 
> target_ulong);
>  #define TB_FLAGS_PRIV_MMU_MASK                3
>  #define TB_FLAGS_PRIV_HYP_ACCESS_MASK   (1 << 2)
>  #define TB_FLAGS_MSTATUS_FS MSTATUS_FS
> +#define TB_FLAGS_MSTATUS_VS MSTATUS_VS
>
>  typedef CPURISCVState CPUArchState;
>  typedef RISCVCPU ArchCPU;
> @@ -426,6 +428,7 @@ static inline void cpu_get_tb_cpu_state(CPURISCVState 
> *env, target_ulong *pc,
>
>  #ifdef CONFIG_USER_ONLY
>      flags |= TB_FLAGS_MSTATUS_FS;
> +    flags |= TB_FLAGS_MSTATUS_VS;
>  #else
>      flags |= cpu_mmu_index(env, 0);
>      if (riscv_cpu_fp_enabled(env)) {
> @@ -440,6 +443,10 @@ static inline void cpu_get_tb_cpu_state(CPURISCVState 
> *env, target_ulong *pc,
>              flags = FIELD_DP32(flags, TB_FLAGS, HLSX, 1);
>          }
>      }
> +
> +    if (riscv_cpu_vector_enabled(env)) {
> +        flags |= env->mstatus & MSTATUS_VS;
> +    }
>  #endif
>
>      *pflags = flags;
> diff --git a/target/riscv/cpu_bits.h b/target/riscv/cpu_bits.h
> index b41e8836c3f..82c48b7b9be 100644
> --- a/target/riscv/cpu_bits.h
> +++ b/target/riscv/cpu_bits.h
> @@ -370,6 +370,7 @@
>  #define MSTATUS_SPIE        0x00000020
>  #define MSTATUS_MPIE        0x00000080
>  #define MSTATUS_SPP         0x00000100
> +#define MSTATUS_VS          0x00000600
>  #define MSTATUS_MPP         0x00001800
>  #define MSTATUS_FS          0x00006000
>  #define MSTATUS_XS          0x00018000
> diff --git a/target/riscv/cpu_helper.c b/target/riscv/cpu_helper.c
> index a2afb95fa11..8f67263a49a 100644
> --- a/target/riscv/cpu_helper.c
> +++ b/target/riscv/cpu_helper.c
> @@ -108,11 +108,24 @@ bool riscv_cpu_fp_enabled(CPURISCVState *env)
>      return false;
>  }
>
> +/* Return true is vector support is currently enabled */
> +bool riscv_cpu_vector_enabled(CPURISCVState *env)
> +{
> +    if (env->mstatus & MSTATUS_VS) {
> +        if (riscv_cpu_virt_enabled(env) && !(env->mstatus_hs & MSTATUS_VS)) {
> +            return false;
> +        }
> +        return true;
> +    }
> +
> +    return false;
> +}
> +
>  void riscv_cpu_swap_hypervisor_regs(CPURISCVState *env)
>  {
>      uint64_t mstatus_mask = MSTATUS_MXR | MSTATUS_SUM | MSTATUS_FS |
>                              MSTATUS_SPP | MSTATUS_SPIE | MSTATUS_SIE |
> -                            MSTATUS64_UXL;
> +                            MSTATUS64_UXL | MSTATUS_VS;
>      bool current_virt = riscv_cpu_virt_enabled(env);
>
>      g_assert(riscv_has_ext(env, RVH));
> diff --git a/target/riscv/csr.c b/target/riscv/csr.c
> index 10ab82ed1fc..50862df9e82 100644
> --- a/target/riscv/csr.c
> +++ b/target/riscv/csr.c
> @@ -268,6 +268,7 @@ static int write_fcsr(CPURISCVState *env, int csrno, 
> target_ulong val)
>          return -RISCV_EXCP_ILLEGAL_INST;
>      }
>      env->mstatus |= MSTATUS_FS;
> +    env->mstatus |= MSTATUS_VS;
>  #endif
>      env->frm = (val & FSR_RD) >> FSR_RD_SHIFT;
>      if (vs(env, csrno) >= 0) {
> @@ -298,6 +299,13 @@ static int read_vxrm(CPURISCVState *env, int csrno, 
> target_ulong *val)
>
>  static int write_vxrm(CPURISCVState *env, int csrno, target_ulong val)
>  {
> +#if !defined(CONFIG_USER_ONLY)
> +    if (!env->debugger && !riscv_cpu_vector_enabled(env)) {
> +        return -1;
> +    }
> +    env->mstatus |= MSTATUS_VS;
> +#endif
> +
>      env->vxrm = val;
>      return 0;
>  }
> @@ -310,6 +318,13 @@ static int read_vxsat(CPURISCVState *env, int csrno, 
> target_ulong *val)
>
>  static int write_vxsat(CPURISCVState *env, int csrno, target_ulong val)
>  {
> +#if !defined(CONFIG_USER_ONLY)
> +    if (!env->debugger && !riscv_cpu_vector_enabled(env)) {
> +        return -1;
> +    }
> +    env->mstatus |= MSTATUS_VS;
> +#endif
> +
>      env->vxsat = val;
>      return 0;
>  }
> @@ -322,6 +337,13 @@ static int read_vstart(CPURISCVState *env, int csrno, 
> target_ulong *val)
>
>  static int write_vstart(CPURISCVState *env, int csrno, target_ulong val)
>  {
> +#if !defined(CONFIG_USER_ONLY)
> +    if (!env->debugger && !riscv_cpu_vector_enabled(env)) {
> +        return -1;
> +    }
> +    env->mstatus |= MSTATUS_VS;
> +#endif
> +
>      env->vstart = val;
>      return 0;
>  }
> @@ -485,7 +507,7 @@ static int write_mstatus(CPURISCVState *env, int csrno, 
> target_ulong val)
>      mask = MSTATUS_SIE | MSTATUS_SPIE | MSTATUS_MIE | MSTATUS_MPIE |
>          MSTATUS_SPP | MSTATUS_FS | MSTATUS_MPRV | MSTATUS_SUM |
>          MSTATUS_MPP | MSTATUS_MXR | MSTATUS_TVM | MSTATUS_TSR |
> -        MSTATUS_TW;
> +        MSTATUS_TW | MSTATUS_VS;
>
>      if (!riscv_cpu_is_32bit(env)) {
>          /*
> @@ -498,6 +520,7 @@ static int write_mstatus(CPURISCVState *env, int csrno, 
> target_ulong val)
>      mstatus = (mstatus & ~mask) | (val & mask);
>
>      dirty = ((mstatus & MSTATUS_FS) == MSTATUS_FS) |
> +            ((mstatus & MSTATUS_VS) == MSTATUS_VS) |
>              ((mstatus & MSTATUS_XS) == MSTATUS_XS);
>      mstatus = set_field(mstatus, MSTATUS_SD, dirty);
>      env->mstatus = mstatus;
> --
> 2.17.1
>
>