On Thu, Mar 12, 2020 at 8:05 AM LIU Zhiwei <zhiwei_liu@c-sky.com> wrote:
>
> The v0.7.1 specification does not define vector status within mstatus.
> A future revision will define the privileged portion of the vector status.
>
> Signed-off-by: LIU Zhiwei <zhiwei_liu@c-sky.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Alistair
> ---
> target/riscv/cpu_bits.h | 15 +++++++++
> target/riscv/csr.c | 75 ++++++++++++++++++++++++++++++++++++++++-
> 2 files changed, 89 insertions(+), 1 deletion(-)
>
> diff --git a/target/riscv/cpu_bits.h b/target/riscv/cpu_bits.h
> index 7f64ee1174..8117e8b5a7 100644
> --- a/target/riscv/cpu_bits.h
> +++ b/target/riscv/cpu_bits.h
> @@ -29,6 +29,14 @@
> #define FSR_NXA (FPEXC_NX << FSR_AEXC_SHIFT)
> #define FSR_AEXC (FSR_NVA | FSR_OFA | FSR_UFA | FSR_DZA | FSR_NXA)
>
> +/* Vector Fixed-Point round model */
> +#define FSR_VXRM_SHIFT 9
> +#define FSR_VXRM (0x3 << FSR_VXRM_SHIFT)
> +
> +/* Vector Fixed-Point saturation flag */
> +#define FSR_VXSAT_SHIFT 8
> +#define FSR_VXSAT (0x1 << FSR_VXSAT_SHIFT)
> +
> /* Control and Status Registers */
>
> /* User Trap Setup */
> @@ -48,6 +56,13 @@
> #define CSR_FRM 0x002
> #define CSR_FCSR 0x003
>
> +/* User Vector CSRs */
> +#define CSR_VSTART 0x008
> +#define CSR_VXSAT 0x009
> +#define CSR_VXRM 0x00a
> +#define CSR_VL 0xc20
> +#define CSR_VTYPE 0xc21
> +
> /* User Timers and Counters */
> #define CSR_CYCLE 0xc00
> #define CSR_TIME 0xc01
> diff --git a/target/riscv/csr.c b/target/riscv/csr.c
> index 11d184cd16..d71c49dfff 100644
> --- a/target/riscv/csr.c
> +++ b/target/riscv/csr.c
> @@ -46,6 +46,10 @@ void riscv_set_csr_ops(int csrno, riscv_csr_operations *ops)
> static int fs(CPURISCVState *env, int csrno)
> {
> #if !defined(CONFIG_USER_ONLY)
> + /* loose check condition for fcsr in vector extension */
> + if ((csrno == CSR_FCSR) && (env->misa & RVV)) {
> + return 0;
> + }
> if (!env->debugger && !riscv_cpu_fp_enabled(env)) {
> return -1;
> }
> @@ -53,6 +57,14 @@ static int fs(CPURISCVState *env, int csrno)
> return 0;
> }
>
> +static int vs(CPURISCVState *env, int csrno)
> +{
> + if (env->misa & RVV) {
> + return 0;
> + }
> + return -1;
> +}
> +
> static int ctr(CPURISCVState *env, int csrno)
> {
> #if !defined(CONFIG_USER_ONLY)
> @@ -174,6 +186,10 @@ static int read_fcsr(CPURISCVState *env, int csrno, target_ulong *val)
> #endif
> *val = (riscv_cpu_get_fflags(env) << FSR_AEXC_SHIFT)
> | (env->frm << FSR_RD_SHIFT);
> + if (vs(env, csrno) >= 0) {
> + *val |= (env->vxrm << FSR_VXRM_SHIFT)
> + | (env->vxsat << FSR_VXSAT_SHIFT);
> + }
> return 0;
> }
>
> @@ -186,10 +202,62 @@ static int write_fcsr(CPURISCVState *env, int csrno, target_ulong val)
> env->mstatus |= MSTATUS_FS;
> #endif
> env->frm = (val & FSR_RD) >> FSR_RD_SHIFT;
> + if (vs(env, csrno) >= 0) {
> + env->vxrm = (val & FSR_VXRM) >> FSR_VXRM_SHIFT;
> + env->vxsat = (val & FSR_VXSAT) >> FSR_VXSAT_SHIFT;
> + }
> riscv_cpu_set_fflags(env, (val & FSR_AEXC) >> FSR_AEXC_SHIFT);
> return 0;
> }
>
> +static int read_vtype(CPURISCVState *env, int csrno, target_ulong *val)
> +{
> + *val = env->vtype;
> + return 0;
> +}
> +
> +static int read_vl(CPURISCVState *env, int csrno, target_ulong *val)
> +{
> + *val = env->vl;
> + return 0;
> +}
> +
> +static int read_vxrm(CPURISCVState *env, int csrno, target_ulong *val)
> +{
> + *val = env->vxrm;
> + return 0;
> +}
> +
> +static int write_vxrm(CPURISCVState *env, int csrno, target_ulong val)
> +{
> + env->vxrm = val;
> + return 0;
> +}
> +
> +static int read_vxsat(CPURISCVState *env, int csrno, target_ulong *val)
> +{
> + *val = env->vxsat;
> + return 0;
> +}
> +
> +static int write_vxsat(CPURISCVState *env, int csrno, target_ulong val)
> +{
> + env->vxsat = val;
> + return 0;
> +}
> +
> +static int read_vstart(CPURISCVState *env, int csrno, target_ulong *val)
> +{
> + *val = env->vstart;
> + return 0;
> +}
> +
> +static int write_vstart(CPURISCVState *env, int csrno, target_ulong val)
> +{
> + env->vstart = val;
> + return 0;
> +}
> +
> /* User Timers and Counters */
> static int read_instret(CPURISCVState *env, int csrno, target_ulong *val)
> {
> @@ -1269,7 +1337,12 @@ static riscv_csr_operations csr_ops[CSR_TABLE_SIZE] = {
> [CSR_FFLAGS] = { fs, read_fflags, write_fflags },
> [CSR_FRM] = { fs, read_frm, write_frm },
> [CSR_FCSR] = { fs, read_fcsr, write_fcsr },
> -
> + /* Vector CSRs */
> + [CSR_VSTART] = { vs, read_vstart, write_vstart },
> + [CSR_VXSAT] = { vs, read_vxsat, write_vxsat },
> + [CSR_VXRM] = { vs, read_vxrm, write_vxrm },
> + [CSR_VL] = { vs, read_vl },
> + [CSR_VTYPE] = { vs, read_vtype },
> /* User Timers and Counters */
> [CSR_CYCLE] = { ctr, read_instret },
> [CSR_INSTRET] = { ctr, read_instret },
> --
> 2.23.0
>