On Thu, 2022-09-29 at 09:09 +0800, weiwei wrote:
> On 2022/9/19 14:29, Mayuresh Chitale wrote:
> > If smstateen is implemented and sstateen0.fcsr is clear then the
> > floating point
> > operations must return illegal instruction exception or virtual
> > instruction
> > trap, if relevant.
> >
> > Signed-off-by: Mayuresh Chitale <mchit...@ventanamicro.com>
> > ---
> > target/riscv/csr.c | 23 +++++++++++++
> > target/riscv/insn_trans/trans_rvf.c.inc | 40
> > +++++++++++++++++++++--
> > target/riscv/insn_trans/trans_rvzfh.c.inc | 12 +++++++
> > 3 files changed, 72 insertions(+), 3 deletions(-)
> >
> > diff --git a/target/riscv/csr.c b/target/riscv/csr.c
> > index 59d5aa74ee..edaecf53ce 100644
> > --- a/target/riscv/csr.c
> > +++ b/target/riscv/csr.c
> > @@ -84,6 +84,10 @@ 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;
> > }
> > @@ -2024,6 +2028,9 @@ static RISCVException
> > write_mstateen0(CPURISCVState *env, int csrno,
> > target_ulong new_val)
> > {
> > uint64_t wr_mask = SMSTATEEN_STATEEN | SMSTATEEN0_HSENVCFG;
> > + if (!riscv_has_ext(env, RVF)) {
> > + wr_mask |= SMSTATEEN0_FCSR;
> > + }
> >
> > return write_mstateen(env, csrno, wr_mask, new_val);
> > }
> > @@ -2072,6 +2079,10 @@ static RISCVException
> > write_mstateen0h(CPURISCVState *env, int csrno,
> > {
> > uint64_t wr_mask = SMSTATEEN_STATEEN | SMSTATEEN0_HSENVCFG;
> >
> > + if (!riscv_has_ext(env, RVF)) {
> > + wr_mask |= SMSTATEEN0_FCSR;
> > + }
> > +
> > return write_mstateenh(env, csrno, wr_mask, new_val);
> > }
> >
> > @@ -2121,6 +2132,10 @@ static RISCVException
> > write_hstateen0(CPURISCVState *env, int csrno,
> > {
> > uint64_t wr_mask = SMSTATEEN_STATEEN | SMSTATEEN0_HSENVCFG;
> >
> > + if (!riscv_has_ext(env, RVF)) {
> > + wr_mask |= SMSTATEEN0_FCSR;
> > + }
> > +
> > return write_hstateen(env, csrno, wr_mask, new_val);
> > }
> >
> > @@ -2172,6 +2187,10 @@ static RISCVException
> > write_hstateen0h(CPURISCVState *env, int csrno,
> > {
> > uint64_t wr_mask = SMSTATEEN_STATEEN | SMSTATEEN0_HSENVCFG;
> >
> > + if (!riscv_has_ext(env, RVF)) {
> > + wr_mask |= SMSTATEEN0_FCSR;
> > + }
> > +
> > return write_hstateenh(env, csrno, wr_mask, new_val);
> > }
> >
> > @@ -2231,6 +2250,10 @@ static RISCVException
> > write_sstateen0(CPURISCVState *env, int csrno,
> > {
> > uint64_t wr_mask = SMSTATEEN_STATEEN | 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..ce8a0cc34b 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)
> >
> > -#define REQUIRE_ZFINX_OR_F(ctx) do {\
> > - if (!ctx->cfg_ptr->ext_zfinx) { \
> > - REQUIRE_EXT(ctx, RVF); \
> > +#ifndef CONFIG_USER_ONLY
> > +static inline bool smstateen_check(DisasContext *ctx, int index)
> > +{
> > + CPUState *cpu = ctx->cs;
> > + CPURISCVState *env = cpu->env_ptr;
> > + uint64_t stateen = env->mstateen[index];
> > +
> > + if (!ctx->cfg_ptr->ext_smstateen || env->priv == PRV_M) {
> > + return true;
> > + }
> > +
> > + if (ctx->virt_enabled) {
> > + stateen &= env->hstateen[index];
> > + }
> > +
> > + if (env->priv == PRV_U && has_ext(ctx, RVS)) {
> > + stateen &= env->sstateen[index];
> > + }
> > +
> > + if (!(stateen & SMSTATEEN0_FCSR)) {
> > + return false;
> > + }
> > +
> > + return true;
> > +}
> > +#else
> > +#define smstateen_check(ctx, index) (true)
> > +#endif
> > +
> > +#define REQUIRE_ZFINX_OR_F(ctx) do { \
> > + if (!has_ext(ctx, RVF)) { \
> > + if (!ctx->cfg_ptr->ext_zfinx) { \
> > + return false; \
> > + } \
> > + if (!smstateen_check(ctx, 0)) { \
> > + return false; \
> > + } \
> > } \
> > } while (0)
>
> I think the potential exception triggered by smstateen_check is not
> correct here:
>
> "return false" can only trigger illegal instruction exception.
>
> However, smstateen_check is for accessing fcsr CSR, It may trigger
> illegal or virtual instruction exception
>
> based on the privilege mode and Xstateen CSRs.
>
> Regards,
>
> Weiwei Li
Ok. Need to check on how to do it.
>
> >
> > diff --git a/target/riscv/insn_trans/trans_rvzfh.c.inc
> > b/target/riscv/insn_trans/trans_rvzfh.c.inc
> > index 5d07150cd0..44d962c920 100644
> > --- a/target/riscv/insn_trans/trans_rvzfh.c.inc
> > +++ b/target/riscv/insn_trans/trans_rvzfh.c.inc
> > @@ -20,18 +20,27 @@
> > if (!ctx->cfg_ptr->ext_zfh) { \
> > return false; \
> > } \
> > + if (!smstateen_check(ctx, 0)) { \
> > + return false; \
> > + } \
> > } while (0)
> >
> > #define REQUIRE_ZHINX_OR_ZFH(ctx) do { \
> > if (!ctx->cfg_ptr->ext_zhinx && !ctx->cfg_ptr->ext_zfh) { \
> > return false; \
> > } \
> > + if (!smstateen_check(ctx, 0)) { \
> > + return false; \
> > + } \
> > } while (0)
> >
> > #define REQUIRE_ZFH_OR_ZFHMIN(ctx) do { \
> > if (!(ctx->cfg_ptr->ext_zfh || ctx->cfg_ptr->ext_zfhmin)) { \
> > return false; \
> > } \
> > + if (!smstateen_check(ctx, 0)) { \
> > + return false; \
> > + } \
> > } while (0)
> >
> > #define REQUIRE_ZFH_OR_ZFHMIN_OR_ZHINX_OR_ZHINXMIN(ctx) do { \
> > @@ -39,6 +48,9 @@
> > ctx->cfg_ptr->ext_zhinx || ctx->cfg_ptr->ext_zhinxmin))
> > { \
> > return false; \
> > } \
> > + if (!smstateen_check(ctx, 0)) { \
> > + return false; \
> > + } \
> > } while (0)
> >
> > static bool trans_flh(DisasContext *ctx, arg_flh *a)
