Re: [PATCH v6 3/5] target/riscv: smstateen check for fcsr

[Mayuresh Chitale <mchitale@ventanamicro.com>]

On Thu, 2022-07-28 at 09:09 +0100, Ben Dooks wrote:
> On 28/07/2022 07:15, Mayuresh Chitale wrote:
> > On Mon, 2022-07-25 at 15:23 +0800, Weiwei Li wrote:
> > > 在 2022/7/24 下午11:49, Mayuresh Chitale 写道:
> > > > On Fri, 2022-07-22 at 09:42 +0800, Weiwei Li wrote:
> > > > > 在 2022/7/21 下午11:31, Mayuresh Chitale 写道:
> > > > > > If smstateen is implemented and sstateen0.fcsr is clear
> > > > > > then
> > > > > > the
> > > > > > floating point operations must return illegal instruction
> > > > > > exception.
> > > > > > 
> > > > > > Signed-off-by: Mayuresh Chitale <mchitale@ventanamicro.com>
> > > > > > ---
> > > > > >    target/riscv/csr.c                        | 23
> > > > > > ++++++++++++++
> > > > > >    target/riscv/insn_trans/trans_rvf.c.inc   | 38
> > > > > > +++++++++++++++++++++--
> > > > > >    target/riscv/insn_trans/trans_rvzfh.c.inc |  4 +++
> > > > > >    3 files changed, 63 insertions(+), 2 deletions(-)
> > > > > > 
> > > > > > diff --git a/target/riscv/csr.c b/target/riscv/csr.c
> > > > > > index ab06b117f9..a597b6cbc7 100644
> > > > > > --- a/target/riscv/csr.c
> > > > > > +++ b/target/riscv/csr.c
> > > > > > @@ -96,6 +96,10 @@ static RISCVException fs(CPURISCVState
> > > > > > *env,
> > > > > > int
> > > > > > csrno)
> > > > > >            !RISCV_CPU(env_cpu(env))->cfg.ext_zfinx) {
> > > > > >            return RISCV_EXCP_ILLEGAL_INST;
> > > > > >        }
> > > > > > +
> > > > > > +    if (!env->debugger && !riscv_cpu_fp_enabled(env)) {
> > > > > > +        return smstateen_acc_ok(env, 0, SMSTATEEN0_FCSR);
> > > > > > +    }
> > > > > >    #endif
> > > > > >        return RISCV_EXCP_NONE;
> > > > > >    }
> > > > > > @@ -1876,6 +1880,9 @@ static RISCVException
> > > > > > write_mstateen0(CPURISCVState *env, int csrno,
> > > > > >                                          target_ulong
> > > > > > new_val)
> > > > > >    {
> > > > > >        uint64_t wr_mask = SMSTATEEN_STATEN |
> > > > > > SMSTATEEN0_HSENVCFG;
> > > > > > +    if (!riscv_has_ext(env, RVF)) {
> > > > > > +        wr_mask |= SMSTATEEN0_FCSR;
> > > > > > +    }
> > > > > >    
> > > > > >        return write_mstateen(env, csrno, wr_mask, new_val);
> > > > > >    }
> > > > > > @@ -1924,6 +1931,10 @@ static RISCVException
> > > > > > write_mstateen0h(CPURISCVState *env, int csrno,
> > > > > >    {
> > > > > >        uint64_t wr_mask = SMSTATEEN_STATEN |
> > > > > > SMSTATEEN0_HSENVCFG;
> > > > > >    
> > > > > > +    if (!riscv_has_ext(env, RVF)) {
> > > > > > +        wr_mask |= SMSTATEEN0_FCSR;
> > > > > > +    }
> > > > > > +
> > > > > >        return write_mstateenh(env, csrno, wr_mask,
> > > > > > new_val);
> > > > > >    }
> > > > > >    
> > > > > > @@ -1973,6 +1984,10 @@ static RISCVException
> > > > > > write_hstateen0(CPURISCVState *env, int csrno,
> > > > > >    {
> > > > > >        uint64_t wr_mask = SMSTATEEN_STATEN |
> > > > > > SMSTATEEN0_HSENVCFG;
> > > > > >    
> > > > > > +    if (!riscv_has_ext(env, RVF)) {
> > > > > > +        wr_mask |= SMSTATEEN0_FCSR;
> > > > > > +    }
> > > > > > +
> > > > > >        return write_hstateen(env, csrno, wr_mask, new_val);
> > > > > >    }
> > > > > >    
> > > > > > @@ -2024,6 +2039,10 @@ static RISCVException
> > > > > > write_hstateen0h(CPURISCVState *env, int csrno,
> > > > > >    {
> > > > > >        uint64_t wr_mask = SMSTATEEN_STATEN |
> > > > > > SMSTATEEN0_HSENVCFG;
> > > > > >    
> > > > > > +    if (!riscv_has_ext(env, RVF)) {
> > > > > > +        wr_mask |= SMSTATEEN0_FCSR;
> > > > > > +    }
> > > > > > +
> > > > > >        return write_hstateenh(env, csrno, wr_mask,
> > > > > > new_val);
> > > > > >    }
> > > > > >    
> > > > > > @@ -2083,6 +2102,10 @@ static RISCVException
> > > > > > write_sstateen0(CPURISCVState *env, int csrno,
> > > > > >    {
> > > > > >        uint64_t wr_mask = SMSTATEEN_STATEN |
> > > > > > SMSTATEEN0_HSENVCFG;
> > > > > >    
> > > > > > +    if (!riscv_has_ext(env, RVF)) {
> > > > > > +        wr_mask |= SMSTATEEN0_FCSR;
> > > > > > +    }
> > > > > > +
> > > > > >        return write_sstateen(env, csrno, wr_mask, new_val);
> > > > > >    }
> > > > > >    
> > > > > > diff --git a/target/riscv/insn_trans/trans_rvf.c.inc
> > > > > > b/target/riscv/insn_trans/trans_rvf.c.inc
> > > > > > index a1d3eb52ad..c43c48336b 100644
> > > > > > --- a/target/riscv/insn_trans/trans_rvf.c.inc
> > > > > > +++ b/target/riscv/insn_trans/trans_rvf.c.inc
> > > > > > @@ -24,9 +24,43 @@
> > > > > >                return false; \
> > > > > >    } while (0)
> > > > > >    
> > > > > > +#ifndef CONFIG_USER_ONLY
> > > > > > +#define SMSTATEEN_CHECK(ctx) do {\
> > > > > > +    CPUState *cpu = ctx->cs; \
> > > > > > +    CPURISCVState *env = cpu->env_ptr; \
> > > > > > +    if (ctx->cfg_ptr->ext_smstateen && \
> > > > > > +        (env->priv < PRV_M)) { \
> > > > > > +        uint64_t stateen = env->mstateen[0]; \
> > > > > > +        uint64_t hstateen = env->hstateen[0]; \
> > > > > > +        uint64_t sstateen = env->sstateen[0]; \
> > > > > > +        if (!(stateen & SMSTATEEN_STATEN)) {\
> > > > > > +            hstateen = 0; \
> > > > > > +            sstateen = 0; \
> > > > > > +        } \
> > > > > > +        if (ctx->virt_enabled) { \
> > > > > > +            stateen &= hstateen; \
> > > > > > +            if (!(hstateen & SMSTATEEN_STATEN)) {\
> > > > > > +                sstateen = 0; \
> > > > > > +            } \
> > > > > > +        } \
> > > > > > +        if (env->priv == PRV_U && has_ext(ctx, RVS))
> > > > > > {\eventually
> > > > > > meaning
> > > > > > +            stateen &= sstateen; \
> > > > > > +        } \
> > > > > > +        if (!(stateen & SMSTATEEN0_FCSR)) { \
> > > > > > +            return false; \
> > > > > > +        } \
> > > > > > +    } \
> 
> given the size of that I would have thought an "static inline"
> function would be easier to write and maintain for SMSTATEEN_CHECK
Ok. I will update in the next version.
> 
>