[v10,09/14] riscv: vector: Support xtheadvector save/restore

Commit Message

Charlie Jenkins Sept. 12, 2024, 5:55 a.m. UTC

Use alternatives to add support for xtheadvector vector save/restore
routines.

Signed-off-by: Charlie Jenkins <[e-mail]>
Reviewed-by: Conor Dooley <[e-mail]>
---
 arch/riscv/include/asm/csr.h           |   6 +
 arch/riscv/include/asm/switch_to.h     |   2 +-
 arch/riscv/include/asm/vector.h        | 225 +++++++++++++++++++++++++--------
 arch/riscv/kernel/cpufeature.c         |   6 +-
 arch/riscv/kernel/kernel_mode_vector.c |   8 +-
 arch/riscv/kernel/process.c            |   4 +-
 arch/riscv/kernel/signal.c             |   6 +-
 arch/riscv/kernel/vector.c             |  12 +-
 8 files changed, 200 insertions(+), 69 deletions(-)

Comments

Andy Chiu Oct. 8, 2024, 5:34 p.m. UTC | #1

Hi Charlie,

Charlie Jenkins <[e-mail]> 於 2024年9月12日 週四 下午1:57寫道：
>
> Use alternatives to add support for xtheadvector vector save/restore
> routines.
>
> Signed-off-by: Charlie Jenkins <[e-mail]>
> Reviewed-by: Conor Dooley <[e-mail]>
> ---
>  arch/riscv/include/asm/csr.h           |   6 +
>  arch/riscv/include/asm/switch_to.h     |   2 +-
>  arch/riscv/include/asm/vector.h        | 225 +++++++++++++++++++++++++--------
>  arch/riscv/kernel/cpufeature.c         |   6 +-
>  arch/riscv/kernel/kernel_mode_vector.c |   8 +-
>  arch/riscv/kernel/process.c            |   4 +-
>  arch/riscv/kernel/signal.c             |   6 +-
>  arch/riscv/kernel/vector.c             |  12 +-
>  8 files changed, 200 insertions(+), 69 deletions(-)
>
> diff --git a/arch/riscv/include/asm/csr.h b/arch/riscv/include/asm/csr.h
> index c0a60c4ed911..b4b3fcb1d142 100644
> --- a/arch/riscv/include/asm/csr.h
> +++ b/arch/riscv/include/asm/csr.h
> @@ -30,6 +30,12 @@
>  #define SR_VS_CLEAN    _AC(0x00000400, UL)
>  #define SR_VS_DIRTY    _AC(0x00000600, UL)
>
> +#define SR_VS_THEAD            _AC(0x01800000, UL) /* xtheadvector Status */
> +#define SR_VS_OFF_THEAD                _AC(0x00000000, UL)
> +#define SR_VS_INITIAL_THEAD    _AC(0x00800000, UL)
> +#define SR_VS_CLEAN_THEAD      _AC(0x01000000, UL)
> +#define SR_VS_DIRTY_THEAD      _AC(0x01800000, UL)
> +
>  #define SR_XS          _AC(0x00018000, UL) /* Extension Status */
>  #define SR_XS_OFF      _AC(0x00000000, UL)
>  #define SR_XS_INITIAL  _AC(0x00008000, UL)
> diff --git a/arch/riscv/include/asm/switch_to.h b/arch/riscv/include/asm/switch_to.h
> index 7594df37cc9f..f9cbebe372b8 100644
> --- a/arch/riscv/include/asm/switch_to.h
> +++ b/arch/riscv/include/asm/switch_to.h
> @@ -99,7 +99,7 @@ do {                                                  \
>         __set_prev_cpu(__prev->thread);                 \
>         if (has_fpu())                                  \
>                 __switch_to_fpu(__prev, __next);        \
> -       if (has_vector())                                       \
> +       if (has_vector() || has_xtheadvector())         \
>                 __switch_to_vector(__prev, __next);     \
>         if (switch_to_should_flush_icache(__next))      \
>                 local_flush_icache_all();               \
> diff --git a/arch/riscv/include/asm/vector.h b/arch/riscv/include/asm/vector.h
> index be7d309cca8a..6fd05efc6837 100644
> --- a/arch/riscv/include/asm/vector.h
> +++ b/arch/riscv/include/asm/vector.h
> @@ -18,6 +18,27 @@
>  #include <asm/cpufeature.h>
>  #include <asm/csr.h>
>  #include <asm/asm.h>
> +#include <asm/vendorid_list.h>
> +#include <asm/vendor_extensions.h>
> +#include <asm/vendor_extensions/thead.h>
> +
> +#define __riscv_v_vstate_or(_val, TYPE) ({                             \

Rather than __riscv_v_vstate_or, shouldn't  __riscv_v_vstate_set() or
__riscv_v_vstate_assign better suit the semantic below?

> +       typeof(_val) _res = _val;                                       \
> +       if (has_xtheadvector()) \
> +               _res = (_res & ~SR_VS_THEAD) | SR_VS_##TYPE##_THEAD;    \
> +       else                                                            \
> +               _res = (_res & ~SR_VS) | SR_VS_##TYPE;                  \
> +       _res;                                                           \
> +})
> +
> +#define __riscv_v_vstate_check(_val, TYPE) ({                          \
> +       bool _res;                                                      \
> +       if (has_xtheadvector()) \
> +               _res = ((_val) & SR_VS_THEAD) == SR_VS_##TYPE##_THEAD;  \
> +       else                                                            \
> +               _res = ((_val) & SR_VS) == SR_VS_##TYPE;                \
> +       _res;                                                           \
> +})
>
>  extern unsigned long riscv_v_vsize;
>  int riscv_v_setup_vsize(void);
> @@ -40,39 +61,62 @@ static __always_inline bool has_vector(void)
>         return riscv_has_extension_unlikely(RISCV_ISA_EXT_ZVE32X);
>  }
>
> +static __always_inline bool has_xtheadvector_no_alternatives(void)
> +{
> +       if (IS_ENABLED(CONFIG_RISCV_ISA_XTHEADVECTOR))
> +               return riscv_isa_vendor_extension_available(THEAD_VENDOR_ID, XTHEADVECTOR);
> +       else
> +               return false;
> +}
> +
> +static __always_inline bool has_xtheadvector(void)
> +{
> +       if (IS_ENABLED(CONFIG_RISCV_ISA_XTHEADVECTOR))
> +               return riscv_has_vendor_extension_unlikely(THEAD_VENDOR_ID,
> +                                                          RISCV_ISA_VENDOR_EXT_XTHEADVECTOR);
> +       else
> +               return false;
> +}
> +
>  static inline void __riscv_v_vstate_clean(struct pt_regs *regs)
>  {
> -       regs->status = (regs->status & ~SR_VS) | SR_VS_CLEAN;
> +       regs->status = __riscv_v_vstate_or(regs->status, CLEAN);
>  }
>
>  static inline void __riscv_v_vstate_dirty(struct pt_regs *regs)
>  {
> -       regs->status = (regs->status & ~SR_VS) | SR_VS_DIRTY;
> +       regs->status = __riscv_v_vstate_or(regs->status, DIRTY);
>  }
>
>  static inline void riscv_v_vstate_off(struct pt_regs *regs)
>  {
> -       regs->status = (regs->status & ~SR_VS) | SR_VS_OFF;
> +       regs->status = __riscv_v_vstate_or(regs->status, OFF);
>  }
>
>  static inline void riscv_v_vstate_on(struct pt_regs *regs)
>  {
> -       regs->status = (regs->status & ~SR_VS) | SR_VS_INITIAL;
> +       regs->status = __riscv_v_vstate_or(regs->status, INITIAL);
>  }
>
>  static inline bool riscv_v_vstate_query(struct pt_regs *regs)
>  {
> -       return (regs->status & SR_VS) != 0;
> +       return !__riscv_v_vstate_check(regs->status, OFF);
>  }
>
>  static __always_inline void riscv_v_enable(void)
>  {
> -       csr_set(CSR_SSTATUS, SR_VS);
> +       if (has_xtheadvector())
> +               csr_set(CSR_SSTATUS, SR_VS_THEAD);
> +       else
> +               csr_set(CSR_SSTATUS, SR_VS);
>  }
>
>  static __always_inline void riscv_v_disable(void)
>  {
> -       csr_clear(CSR_SSTATUS, SR_VS);
> +       if (has_xtheadvector())
> +               csr_clear(CSR_SSTATUS, SR_VS_THEAD);
> +       else
> +               csr_clear(CSR_SSTATUS, SR_VS);
>  }
>
>  static __always_inline void __vstate_csr_save(struct __riscv_v_ext_state *dest)
> @@ -81,10 +125,36 @@ static __always_inline void __vstate_csr_save(struct __riscv_v_ext_state *dest)
>                 "csrr   %0, " __stringify(CSR_VSTART) "\n\t"
>                 "csrr   %1, " __stringify(CSR_VTYPE) "\n\t"
>                 "csrr   %2, " __stringify(CSR_VL) "\n\t"
> -               "csrr   %3, " __stringify(CSR_VCSR) "\n\t"
> -               "csrr   %4, " __stringify(CSR_VLENB) "\n\t"
>                 : "=r" (dest->vstart), "=r" (dest->vtype), "=r" (dest->vl),
> -                 "=r" (dest->vcsr), "=r" (dest->vlenb) : :);
> +               "=r" (dest->vcsr) : :);
> +
> +       if (has_xtheadvector()) {
> +               unsigned long status;
> +
> +               /*
> +                * CSR_VCSR is defined as
> +                * [2:1] - vxrm[1:0]
> +                * [0] - vxsat
> +                * The earlier vector spec implemented by T-Head uses separate
> +                * registers for the same bit-elements, so just combine those
> +                * into the existing output field.
> +                *
> +                * Additionally T-Head cores need FS to be enabled when accessing
> +                * the VXRM and VXSAT CSRs, otherwise ending in illegal instructions.
> +                * Though the cores do not implement the VXRM and VXSAT fields in the
> +                * FCSR CSR that vector-0.7.1 specifies.
> +                */
> +               status = csr_read_set(CSR_STATUS, SR_FS_DIRTY);
> +               dest->vcsr = csr_read(CSR_VXSAT) | csr_read(CSR_VXRM) << CSR_VXRM_SHIFT;
> +
> +               dest->vlenb = riscv_v_vsize / 32;
> +
> +               if ((status & SR_FS) != SR_FS_DIRTY)
> +                       csr_write(CSR_STATUS, status);
> +       } else {
> +               dest->vcsr = csr_read(CSR_VCSR);
> +               dest->vlenb = csr_read(CSR_VLENB);
> +       }
>  }
>
>  static __always_inline void __vstate_csr_restore(struct __riscv_v_ext_state *src)
> @@ -95,9 +165,25 @@ static __always_inline void __vstate_csr_restore(struct __riscv_v_ext_state *src
>                 "vsetvl  x0, %2, %1\n\t"
>                 ".option pop\n\t"
>                 "csrw   " __stringify(CSR_VSTART) ", %0\n\t"
> -               "csrw   " __stringify(CSR_VCSR) ", %3\n\t"
> -               : : "r" (src->vstart), "r" (src->vtype), "r" (src->vl),
> -                   "r" (src->vcsr) :);
> +               : : "r" (src->vstart), "r" (src->vtype), "r" (src->vl));
> +
> +       if (has_xtheadvector()) {
> +               unsigned long status = csr_read(CSR_SSTATUS);
> +
> +               /*
> +                * Similar to __vstate_csr_save above, restore values for the
> +                * separate VXRM and VXSAT CSRs from the vcsr variable.
> +                */
> +               status = csr_read_set(CSR_STATUS, SR_FS_DIRTY);
> +
> +               csr_write(CSR_VXRM, (src->vcsr >> CSR_VXRM_SHIFT) & CSR_VXRM_MASK);
> +               csr_write(CSR_VXSAT, src->vcsr & CSR_VXSAT_MASK);
> +
> +               if ((status & SR_FS) != SR_FS_DIRTY)
> +                       csr_write(CSR_STATUS, status);
> +       } else {
> +               csr_write(CSR_VCSR, src->vcsr);
> +       }
>  }
>
>  static inline void __riscv_v_vstate_save(struct __riscv_v_ext_state *save_to,
> @@ -107,19 +193,33 @@ static inline void __riscv_v_vstate_save(struct __riscv_v_ext_state *save_to,
>
>         riscv_v_enable();
>         __vstate_csr_save(save_to);
> -       asm volatile (
> -               ".option push\n\t"
> -               ".option arch, +zve32x\n\t"
> -               "vsetvli        %0, x0, e8, m8, ta, ma\n\t"
> -               "vse8.v         v0, (%1)\n\t"
> -               "add            %1, %1, %0\n\t"
> -               "vse8.v         v8, (%1)\n\t"
> -               "add            %1, %1, %0\n\t"
> -               "vse8.v         v16, (%1)\n\t"
> -               "add            %1, %1, %0\n\t"
> -               "vse8.v         v24, (%1)\n\t"
> -               ".option pop\n\t"
> -               : "=&r" (vl) : "r" (datap) : "memory");
> +       if (has_xtheadvector()) {
> +               asm volatile (
> +                       "mv t0, %0\n\t"
> +                       THEAD_VSETVLI_T4X0E8M8D1
> +                       THEAD_VSB_V_V0T0
> +                       "add            t0, t0, t4\n\t"
> +                       THEAD_VSB_V_V0T0
> +                       "add            t0, t0, t4\n\t"
> +                       THEAD_VSB_V_V0T0
> +                       "add            t0, t0, t4\n\t"
> +                       THEAD_VSB_V_V0T0
> +                       : : "r" (datap) : "memory", "t0", "t4");
> +       } else {
> +               asm volatile (
> +                       ".option push\n\t"
> +                       ".option arch, +zve32x\n\t"
> +                       "vsetvli        %0, x0, e8, m8, ta, ma\n\t"
> +                       "vse8.v         v0, (%1)\n\t"
> +                       "add            %1, %1, %0\n\t"
> +                       "vse8.v         v8, (%1)\n\t"
> +                       "add            %1, %1, %0\n\t"
> +                       "vse8.v         v16, (%1)\n\t"
> +                       "add            %1, %1, %0\n\t"
> +                       "vse8.v         v24, (%1)\n\t"
> +                       ".option pop\n\t"
> +                       : "=&r" (vl) : "r" (datap) : "memory");
> +       }
>         riscv_v_disable();
>  }
>
> @@ -129,28 +229,51 @@ static inline void __riscv_v_vstate_restore(struct __riscv_v_ext_state *restore_
>         unsigned long vl;
>
>         riscv_v_enable();
> -       asm volatile (
> -               ".option push\n\t"
> -               ".option arch, +zve32x\n\t"
> -               "vsetvli        %0, x0, e8, m8, ta, ma\n\t"
> -               "vle8.v         v0, (%1)\n\t"
> -               "add            %1, %1, %0\n\t"
> -               "vle8.v         v8, (%1)\n\t"
> -               "add            %1, %1, %0\n\t"
> -               "vle8.v         v16, (%1)\n\t"
> -               "add            %1, %1, %0\n\t"
> -               "vle8.v         v24, (%1)\n\t"
> -               ".option pop\n\t"
> -               : "=&r" (vl) : "r" (datap) : "memory");
> +       if (has_xtheadvector()) {
> +               asm volatile (
> +                       "mv t0, %0\n\t"
> +                       THEAD_VSETVLI_T4X0E8M8D1
> +                       THEAD_VLB_V_V0T0
> +                       "add            t0, t0, t4\n\t"
> +                       THEAD_VLB_V_V0T0
> +                       "add            t0, t0, t4\n\t"
> +                       THEAD_VLB_V_V0T0
> +                       "add            t0, t0, t4\n\t"
> +                       THEAD_VLB_V_V0T0
> +                       : : "r" (datap) : "memory", "t0", "t4");
> +       } else {
> +               asm volatile (
> +                       ".option push\n\t"
> +                       ".option arch, +zve32x\n\t"
> +                       "vsetvli        %0, x0, e8, m8, ta, ma\n\t"
> +                       "vle8.v         v0, (%1)\n\t"
> +                       "add            %1, %1, %0\n\t"
> +                       "vle8.v         v8, (%1)\n\t"
> +                       "add            %1, %1, %0\n\t"
> +                       "vle8.v         v16, (%1)\n\t"
> +                       "add            %1, %1, %0\n\t"
> +                       "vle8.v         v24, (%1)\n\t"
> +                       ".option pop\n\t"
> +                       : "=&r" (vl) : "r" (datap) : "memory");
> +       }
>         __vstate_csr_restore(restore_from);
>         riscv_v_disable();
>  }
>
>  static inline void __riscv_v_vstate_discard(void)
>  {
> -       unsigned long vl, vtype_inval = 1UL << (BITS_PER_LONG - 1);
> +       unsigned long vtype_inval = 1UL << (BITS_PER_LONG - 1);
>
>         riscv_v_enable();
> +       if (has_xtheadvector())
> +               asm volatile (THEAD_VSETVLI_X0X0E8M8D1);
> +       else
> +               asm volatile (
> +                       ".option push\n\t"
> +                       ".option arch, +v\n\t"
> +                       "vsetvli        x0, x0, e8, m8, ta, ma\n\t"
> +                       ".option pop\n\t");
> +
>         asm volatile (
>                 ".option push\n\t"
>                 ".option arch, +zve32x\n\t"
> @@ -159,25 +282,25 @@ static inline void __riscv_v_vstate_discard(void)
>                 "vmv.v.i        v8, -1\n\t"
>                 "vmv.v.i        v16, -1\n\t"
>                 "vmv.v.i        v24, -1\n\t"
> -               "vsetvl         %0, x0, %1\n\t"
> +               "vsetvl         x0, x0, %0\n\t"
>                 ".option pop\n\t"
> -               : "=&r" (vl) : "r" (vtype_inval) : "memory");
> +               : : "r" (vtype_inval));
> +
>         riscv_v_disable();
>  }
>
>  static inline void riscv_v_vstate_discard(struct pt_regs *regs)
>  {
> -       if ((regs->status & SR_VS) == SR_VS_OFF)
> -               return;
> -
> -       __riscv_v_vstate_discard();
> -       __riscv_v_vstate_dirty(regs);
> +       if (riscv_v_vstate_query(regs)) {
> +               __riscv_v_vstate_discard();
> +               __riscv_v_vstate_dirty(regs);
> +       }
>  }
>
>  static inline void riscv_v_vstate_save(struct __riscv_v_ext_state *vstate,
>                                        struct pt_regs *regs)
>  {
> -       if ((regs->status & SR_VS) == SR_VS_DIRTY) {
> +       if (__riscv_v_vstate_check(regs->status, DIRTY)) {
>                 __riscv_v_vstate_save(vstate, vstate->datap);
>                 __riscv_v_vstate_clean(regs);
>         }
> @@ -186,7 +309,7 @@ static inline void riscv_v_vstate_save(struct __riscv_v_ext_state *vstate,
>  static inline void riscv_v_vstate_restore(struct __riscv_v_ext_state *vstate,
>                                           struct pt_regs *regs)
>  {
> -       if ((regs->status & SR_VS) != SR_VS_OFF) {
> +       if (riscv_v_vstate_query(regs)) {
>                 __riscv_v_vstate_restore(vstate, vstate->datap);
>                 __riscv_v_vstate_clean(regs);
>         }
> @@ -195,7 +318,7 @@ static inline void riscv_v_vstate_restore(struct __riscv_v_ext_state *vstate,
>  static inline void riscv_v_vstate_set_restore(struct task_struct *task,
>                                               struct pt_regs *regs)
>  {
> -       if ((regs->status & SR_VS) != SR_VS_OFF) {
> +       if (riscv_v_vstate_query(regs)) {
>                 set_tsk_thread_flag(task, TIF_RISCV_V_DEFER_RESTORE);
>                 riscv_v_vstate_on(regs);
>         }
> @@ -268,6 +391,8 @@ struct pt_regs;
>
>  static inline int riscv_v_setup_vsize(void) { return -EOPNOTSUPP; }
>  static __always_inline bool has_vector(void) { return false; }
> +static __always_inline bool has_xtheadvector_no_alternatives(void) { return false; }
> +static __always_inline bool has_xtheadvector(void) { return false; }
>  static inline bool riscv_v_first_use_handler(struct pt_regs *regs) { return false; }
>  static inline bool riscv_v_vstate_query(struct pt_regs *regs) { return false; }
>  static inline bool riscv_v_vstate_ctrl_user_allowed(void) { return false; }
> diff --git a/arch/riscv/kernel/cpufeature.c b/arch/riscv/kernel/cpufeature.c
> index 9340efd79af9..56b5054b8f86 100644
> --- a/arch/riscv/kernel/cpufeature.c
> +++ b/arch/riscv/kernel/cpufeature.c
> @@ -867,8 +867,7 @@ static int __init riscv_fill_hwcap_from_ext_list(unsigned long *isa2hwcap)
>                 riscv_fill_vendor_ext_list(cpu);
>         }
>
> -       if (riscv_isa_vendor_extension_available(THEAD_VENDOR_ID, XTHEADVECTOR) &&
> -           has_thead_homogeneous_vlenb() < 0) {
> +       if (has_xtheadvector_no_alternatives() && has_thead_homogeneous_vlenb() < 0) {
>                 pr_warn("Unsupported heterogeneous vlenb detected, vector extension disabled.\n");
>                 disable_xtheadvector();
>         }
> @@ -925,7 +924,8 @@ void __init riscv_fill_hwcap(void)
>                 elf_hwcap &= ~COMPAT_HWCAP_ISA_F;
>         }
>
> -       if (__riscv_isa_extension_available(NULL, RISCV_ISA_EXT_ZVE32X)) {
> +       if (__riscv_isa_extension_available(NULL, RISCV_ISA_EXT_ZVE32X) ||
> +           has_xtheadvector_no_alternatives()) {
>                 /*
>                  * This cannot fail when called on the boot hart
>                  */
> diff --git a/arch/riscv/kernel/kernel_mode_vector.c b/arch/riscv/kernel/kernel_mode_vector.c
> index 6afe80c7f03a..99972a48e86b 100644
> --- a/arch/riscv/kernel/kernel_mode_vector.c
> +++ b/arch/riscv/kernel/kernel_mode_vector.c
> @@ -143,7 +143,7 @@ static int riscv_v_start_kernel_context(bool *is_nested)
>
>         /* Transfer the ownership of V from user to kernel, then save */
>         riscv_v_start(RISCV_PREEMPT_V | RISCV_PREEMPT_V_DIRTY);
> -       if ((task_pt_regs(current)->status & SR_VS) == SR_VS_DIRTY) {
> +       if (__riscv_v_vstate_check(task_pt_regs(current)->status, DIRTY)) {
>                 uvstate = &current->thread.vstate;
>                 __riscv_v_vstate_save(uvstate, uvstate->datap);
>         }
> @@ -160,7 +160,7 @@ asmlinkage void riscv_v_context_nesting_start(struct pt_regs *regs)
>                 return;
>
>         depth = riscv_v_ctx_get_depth();
> -       if (depth == 0 && (regs->status & SR_VS) == SR_VS_DIRTY)
> +       if (depth == 0 && __riscv_v_vstate_check(regs->status, DIRTY))
>                 riscv_preempt_v_set_dirty();
>
>         riscv_v_ctx_depth_inc();
> @@ -208,7 +208,7 @@ void kernel_vector_begin(void)
>  {
>         bool nested = false;
>
> -       if (WARN_ON(!has_vector()))
> +       if (WARN_ON(!(has_vector() || has_xtheadvector())))
>                 return;
>
>         BUG_ON(!may_use_simd());
> @@ -236,7 +236,7 @@ EXPORT_SYMBOL_GPL(kernel_vector_begin);
>   */
>  void kernel_vector_end(void)
>  {
> -       if (WARN_ON(!has_vector()))
> +       if (WARN_ON(!(has_vector() || has_xtheadvector())))
>                 return;
>
>         riscv_v_disable();
> diff --git a/arch/riscv/kernel/process.c b/arch/riscv/kernel/process.c
> index e4bc61c4e58a..191023decd16 100644
> --- a/arch/riscv/kernel/process.c
> +++ b/arch/riscv/kernel/process.c
> @@ -176,7 +176,7 @@ void flush_thread(void)
>  void arch_release_task_struct(struct task_struct *tsk)
>  {
>         /* Free the vector context of datap. */
> -       if (has_vector())
> +       if (has_vector() || has_xtheadvector())
>                 riscv_v_thread_free(tsk);
>  }
>
> @@ -222,7 +222,7 @@ int copy_thread(struct task_struct *p, const struct kernel_clone_args *args)
>                 p->thread.s[0] = 0;
>         }
>         p->thread.riscv_v_flags = 0;
> -       if (has_vector())
> +       if (has_vector() || has_xtheadvector())
>                 riscv_v_thread_alloc(p);
>         p->thread.ra = (unsigned long)ret_from_fork;
>         p->thread.sp = (unsigned long)childregs; /* kernel sp */
> diff --git a/arch/riscv/kernel/signal.c b/arch/riscv/kernel/signal.c
> index dcd282419456..94e905eea1de 100644
> --- a/arch/riscv/kernel/signal.c
> +++ b/arch/riscv/kernel/signal.c
> @@ -189,7 +189,7 @@ static long restore_sigcontext(struct pt_regs *regs,
>
>                         return 0;
>                 case RISCV_V_MAGIC:
> -                       if (!has_vector() || !riscv_v_vstate_query(regs) ||
> +                       if (!(has_vector() || has_xtheadvector()) || !riscv_v_vstate_query(regs) ||
>                             size != riscv_v_sc_size)
>                                 return -EINVAL;
>
> @@ -211,7 +211,7 @@ static size_t get_rt_frame_size(bool cal_all)
>
>         frame_size = sizeof(*frame);
>
> -       if (has_vector()) {
> +       if (has_vector() || has_xtheadvector()) {
>                 if (cal_all || riscv_v_vstate_query(task_pt_regs(current)))
>                         total_context_size += riscv_v_sc_size;
>         }
> @@ -284,7 +284,7 @@ static long setup_sigcontext(struct rt_sigframe __user *frame,
>         if (has_fpu())
>                 err |= save_fp_state(regs, &sc->sc_fpregs);
>         /* Save the vector state. */
> -       if (has_vector() && riscv_v_vstate_query(regs))
> +       if ((has_vector() || has_xtheadvector()) && riscv_v_vstate_query(regs))
>                 err |= save_v_state(regs, (void __user **)&sc_ext_ptr);
>         /* Write zero to fp-reserved space and check it on restore_sigcontext */
>         err |= __put_user(0, &sc->sc_extdesc.reserved);
> diff --git a/arch/riscv/kernel/vector.c b/arch/riscv/kernel/vector.c
> index 9775d6a9c8ee..f3e1de574050 100644
> --- a/arch/riscv/kernel/vector.c
> +++ b/arch/riscv/kernel/vector.c
> @@ -63,7 +63,7 @@ int riscv_v_setup_vsize(void)
>
>  void __init riscv_v_setup_ctx_cache(void)
>  {
> -       if (!has_vector())
> +       if (!(has_vector() || has_xtheadvector()))
>                 return;
>
>         riscv_v_user_cachep = kmem_cache_create_usercopy("riscv_vector_ctx",
> @@ -183,7 +183,7 @@ bool riscv_v_first_use_handler(struct pt_regs *regs)
>         u32 __user *epc = (u32 __user *)regs->epc;
>         u32 insn = (u32)regs->badaddr;
>
> -       if (!has_vector())
> +       if (!(has_vector() || has_xtheadvector()))
>                 return false;
>
>         /* Do not handle if V is not supported, or disabled */
> @@ -226,7 +226,7 @@ void riscv_v_vstate_ctrl_init(struct task_struct *tsk)
>         bool inherit;
>         int cur, next;
>
> -       if (!has_vector())
> +       if (!(has_vector() || has_xtheadvector()))
>                 return;
>
>         next = riscv_v_ctrl_get_next(tsk);
> @@ -248,7 +248,7 @@ void riscv_v_vstate_ctrl_init(struct task_struct *tsk)
>
>  long riscv_v_vstate_ctrl_get_current(void)
>  {
> -       if (!has_vector())
> +       if (!(has_vector() || has_xtheadvector()))
>                 return -EINVAL;
>
>         return current->thread.vstate_ctrl & PR_RISCV_V_VSTATE_CTRL_MASK;
> @@ -259,7 +259,7 @@ long riscv_v_vstate_ctrl_set_current(unsigned long arg)
>         bool inherit;
>         int cur, next;
>
> -       if (!has_vector())
> +       if (!(has_vector() || has_xtheadvector()))
>                 return -EINVAL;
>
>         if (arg & ~PR_RISCV_V_VSTATE_CTRL_MASK)
> @@ -309,7 +309,7 @@ static struct ctl_table riscv_v_default_vstate_table[] = {
>
>  static int __init riscv_v_sysctl_init(void)
>  {
> -       if (has_vector())
> +       if (has_vector() || has_xtheadvector())
>                 if (!register_sysctl("abi", riscv_v_default_vstate_table))
>                         return -EINVAL;
>         return 0;
>
> --
> 2.45.0
>
>
> _______________________________________________
> linux-riscv mailing list
> [e-mail]
> http://lists.infradead.org/mailman/listinfo/linux-riscv

For the rest of this patch:

Reviewed-by: Andy Chiu <[e-mail]>

Thanks,
Andy

Patch

diff --git a/arch/riscv/include/asm/csr.h b/arch/riscv/include/asm/csr.h
index c0a60c4ed911..b4b3fcb1d142 100644
--- a/arch/riscv/include/asm/csr.h
+++ b/arch/riscv/include/asm/csr.h
@@ -30,6 +30,12 @@ 
 #define SR_VS_CLEAN	_AC(0x00000400, UL)
 #define SR_VS_DIRTY	_AC(0x00000600, UL)
 
+#define SR_VS_THEAD		_AC(0x01800000, UL) /* xtheadvector Status */
+#define SR_VS_OFF_THEAD		_AC(0x00000000, UL)
+#define SR_VS_INITIAL_THEAD	_AC(0x00800000, UL)
+#define SR_VS_CLEAN_THEAD	_AC(0x01000000, UL)
+#define SR_VS_DIRTY_THEAD	_AC(0x01800000, UL)
+
 #define SR_XS		_AC(0x00018000, UL) /* Extension Status */
 #define SR_XS_OFF	_AC(0x00000000, UL)
 #define SR_XS_INITIAL	_AC(0x00008000, UL)
diff --git a/arch/riscv/include/asm/switch_to.h b/arch/riscv/include/asm/switch_to.h
index 7594df37cc9f..f9cbebe372b8 100644
--- a/arch/riscv/include/asm/switch_to.h
+++ b/arch/riscv/include/asm/switch_to.h
@@ -99,7 +99,7 @@  do {							\
 	__set_prev_cpu(__prev->thread);			\
 	if (has_fpu())					\
 		__switch_to_fpu(__prev, __next);	\
-	if (has_vector())					\
+	if (has_vector() || has_xtheadvector())		\
 		__switch_to_vector(__prev, __next);	\
 	if (switch_to_should_flush_icache(__next))	\
 		local_flush_icache_all();		\
diff --git a/arch/riscv/include/asm/vector.h b/arch/riscv/include/asm/vector.h
index be7d309cca8a..6fd05efc6837 100644
--- a/arch/riscv/include/asm/vector.h
+++ b/arch/riscv/include/asm/vector.h
@@ -18,6 +18,27 @@ 
 #include <asm/cpufeature.h>
 #include <asm/csr.h>
 #include <asm/asm.h>
+#include <asm/vendorid_list.h>
+#include <asm/vendor_extensions.h>
+#include <asm/vendor_extensions/thead.h>
+
+#define __riscv_v_vstate_or(_val, TYPE) ({				\
+	typeof(_val) _res = _val;					\
+	if (has_xtheadvector()) \
+		_res = (_res & ~SR_VS_THEAD) | SR_VS_##TYPE##_THEAD;	\
+	else								\
+		_res = (_res & ~SR_VS) | SR_VS_##TYPE;			\
+	_res;								\
+})
+
+#define __riscv_v_vstate_check(_val, TYPE) ({				\
+	bool _res;							\
+	if (has_xtheadvector()) \
+		_res = ((_val) & SR_VS_THEAD) == SR_VS_##TYPE##_THEAD;	\
+	else								\
+		_res = ((_val) & SR_VS) == SR_VS_##TYPE;		\
+	_res;								\
+})
 
 extern unsigned long riscv_v_vsize;
 int riscv_v_setup_vsize(void);
@@ -40,39 +61,62 @@  static __always_inline bool has_vector(void)
 	return riscv_has_extension_unlikely(RISCV_ISA_EXT_ZVE32X);
 }
 
+static __always_inline bool has_xtheadvector_no_alternatives(void)
+{
+	if (IS_ENABLED(CONFIG_RISCV_ISA_XTHEADVECTOR))
+		return riscv_isa_vendor_extension_available(THEAD_VENDOR_ID, XTHEADVECTOR);
+	else
+		return false;
+}
+
+static __always_inline bool has_xtheadvector(void)
+{
+	if (IS_ENABLED(CONFIG_RISCV_ISA_XTHEADVECTOR))
+		return riscv_has_vendor_extension_unlikely(THEAD_VENDOR_ID,
+							   RISCV_ISA_VENDOR_EXT_XTHEADVECTOR);
+	else
+		return false;
+}
+
 static inline void __riscv_v_vstate_clean(struct pt_regs *regs)
 {
-	regs->status = (regs->status & ~SR_VS) | SR_VS_CLEAN;
+	regs->status = __riscv_v_vstate_or(regs->status, CLEAN);
 }
 
 static inline void __riscv_v_vstate_dirty(struct pt_regs *regs)
 {
-	regs->status = (regs->status & ~SR_VS) | SR_VS_DIRTY;
+	regs->status = __riscv_v_vstate_or(regs->status, DIRTY);
 }
 
 static inline void riscv_v_vstate_off(struct pt_regs *regs)
 {
-	regs->status = (regs->status & ~SR_VS) | SR_VS_OFF;
+	regs->status = __riscv_v_vstate_or(regs->status, OFF);
 }
 
 static inline void riscv_v_vstate_on(struct pt_regs *regs)
 {
-	regs->status = (regs->status & ~SR_VS) | SR_VS_INITIAL;
+	regs->status = __riscv_v_vstate_or(regs->status, INITIAL);
 }
 
 static inline bool riscv_v_vstate_query(struct pt_regs *regs)
 {
-	return (regs->status & SR_VS) != 0;
+	return !__riscv_v_vstate_check(regs->status, OFF);
 }
 
 static __always_inline void riscv_v_enable(void)
 {
-	csr_set(CSR_SSTATUS, SR_VS);
+	if (has_xtheadvector())
+		csr_set(CSR_SSTATUS, SR_VS_THEAD);
+	else
+		csr_set(CSR_SSTATUS, SR_VS);
 }
 
 static __always_inline void riscv_v_disable(void)
 {
-	csr_clear(CSR_SSTATUS, SR_VS);
+	if (has_xtheadvector())
+		csr_clear(CSR_SSTATUS, SR_VS_THEAD);
+	else
+		csr_clear(CSR_SSTATUS, SR_VS);
 }
 
 static __always_inline void __vstate_csr_save(struct __riscv_v_ext_state *dest)
@@ -81,10 +125,36 @@  static __always_inline void __vstate_csr_save(struct __riscv_v_ext_state *dest)
 		"csrr	%0, " __stringify(CSR_VSTART) "\n\t"
 		"csrr	%1, " __stringify(CSR_VTYPE) "\n\t"
 		"csrr	%2, " __stringify(CSR_VL) "\n\t"
-		"csrr	%3, " __stringify(CSR_VCSR) "\n\t"
-		"csrr	%4, " __stringify(CSR_VLENB) "\n\t"
 		: "=r" (dest->vstart), "=r" (dest->vtype), "=r" (dest->vl),
-		  "=r" (dest->vcsr), "=r" (dest->vlenb) : :);
+		"=r" (dest->vcsr) : :);
+
+	if (has_xtheadvector()) {
+		unsigned long status;
+
+		/*
+		 * CSR_VCSR is defined as
+		 * [2:1] - vxrm[1:0]
+		 * [0] - vxsat
+		 * The earlier vector spec implemented by T-Head uses separate
+		 * registers for the same bit-elements, so just combine those
+		 * into the existing output field.
+		 *
+		 * Additionally T-Head cores need FS to be enabled when accessing
+		 * the VXRM and VXSAT CSRs, otherwise ending in illegal instructions.
+		 * Though the cores do not implement the VXRM and VXSAT fields in the
+		 * FCSR CSR that vector-0.7.1 specifies.
+		 */
+		status = csr_read_set(CSR_STATUS, SR_FS_DIRTY);
+		dest->vcsr = csr_read(CSR_VXSAT) | csr_read(CSR_VXRM) << CSR_VXRM_SHIFT;
+
+		dest->vlenb = riscv_v_vsize / 32;
+
+		if ((status & SR_FS) != SR_FS_DIRTY)
+			csr_write(CSR_STATUS, status);
+	} else {
+		dest->vcsr = csr_read(CSR_VCSR);
+		dest->vlenb = csr_read(CSR_VLENB);
+	}
 }
 
 static __always_inline void __vstate_csr_restore(struct __riscv_v_ext_state *src)
@@ -95,9 +165,25 @@  static __always_inline void __vstate_csr_restore(struct __riscv_v_ext_state *src
 		"vsetvl	 x0, %2, %1\n\t"
 		".option pop\n\t"
 		"csrw	" __stringify(CSR_VSTART) ", %0\n\t"
-		"csrw	" __stringify(CSR_VCSR) ", %3\n\t"
-		: : "r" (src->vstart), "r" (src->vtype), "r" (src->vl),
-		    "r" (src->vcsr) :);
+		: : "r" (src->vstart), "r" (src->vtype), "r" (src->vl));
+
+	if (has_xtheadvector()) {
+		unsigned long status = csr_read(CSR_SSTATUS);
+
+		/*
+		 * Similar to __vstate_csr_save above, restore values for the
+		 * separate VXRM and VXSAT CSRs from the vcsr variable.
+		 */
+		status = csr_read_set(CSR_STATUS, SR_FS_DIRTY);
+
+		csr_write(CSR_VXRM, (src->vcsr >> CSR_VXRM_SHIFT) & CSR_VXRM_MASK);
+		csr_write(CSR_VXSAT, src->vcsr & CSR_VXSAT_MASK);
+
+		if ((status & SR_FS) != SR_FS_DIRTY)
+			csr_write(CSR_STATUS, status);
+	} else {
+		csr_write(CSR_VCSR, src->vcsr);
+	}
 }
 
 static inline void __riscv_v_vstate_save(struct __riscv_v_ext_state *save_to,
@@ -107,19 +193,33 @@  static inline void __riscv_v_vstate_save(struct __riscv_v_ext_state *save_to,
 
 	riscv_v_enable();
 	__vstate_csr_save(save_to);
-	asm volatile (
-		".option push\n\t"
-		".option arch, +zve32x\n\t"
-		"vsetvli	%0, x0, e8, m8, ta, ma\n\t"
-		"vse8.v		v0, (%1)\n\t"
-		"add		%1, %1, %0\n\t"
-		"vse8.v		v8, (%1)\n\t"
-		"add		%1, %1, %0\n\t"
-		"vse8.v		v16, (%1)\n\t"
-		"add		%1, %1, %0\n\t"
-		"vse8.v		v24, (%1)\n\t"
-		".option pop\n\t"
-		: "=&r" (vl) : "r" (datap) : "memory");
+	if (has_xtheadvector()) {
+		asm volatile (
+			"mv t0, %0\n\t"
+			THEAD_VSETVLI_T4X0E8M8D1
+			THEAD_VSB_V_V0T0
+			"add		t0, t0, t4\n\t"
+			THEAD_VSB_V_V0T0
+			"add		t0, t0, t4\n\t"
+			THEAD_VSB_V_V0T0
+			"add		t0, t0, t4\n\t"
+			THEAD_VSB_V_V0T0
+			: : "r" (datap) : "memory", "t0", "t4");
+	} else {
+		asm volatile (
+			".option push\n\t"
+			".option arch, +zve32x\n\t"
+			"vsetvli	%0, x0, e8, m8, ta, ma\n\t"
+			"vse8.v		v0, (%1)\n\t"
+			"add		%1, %1, %0\n\t"
+			"vse8.v		v8, (%1)\n\t"
+			"add		%1, %1, %0\n\t"
+			"vse8.v		v16, (%1)\n\t"
+			"add		%1, %1, %0\n\t"
+			"vse8.v		v24, (%1)\n\t"
+			".option pop\n\t"
+			: "=&r" (vl) : "r" (datap) : "memory");
+	}
 	riscv_v_disable();
 }
 
@@ -129,28 +229,51 @@  static inline void __riscv_v_vstate_restore(struct __riscv_v_ext_state *restore_
 	unsigned long vl;
 
 	riscv_v_enable();
-	asm volatile (
-		".option push\n\t"
-		".option arch, +zve32x\n\t"
-		"vsetvli	%0, x0, e8, m8, ta, ma\n\t"
-		"vle8.v		v0, (%1)\n\t"
-		"add		%1, %1, %0\n\t"
-		"vle8.v		v8, (%1)\n\t"
-		"add		%1, %1, %0\n\t"
-		"vle8.v		v16, (%1)\n\t"
-		"add		%1, %1, %0\n\t"
-		"vle8.v		v24, (%1)\n\t"
-		".option pop\n\t"
-		: "=&r" (vl) : "r" (datap) : "memory");
+	if (has_xtheadvector()) {
+		asm volatile (
+			"mv t0, %0\n\t"
+			THEAD_VSETVLI_T4X0E8M8D1
+			THEAD_VLB_V_V0T0
+			"add		t0, t0, t4\n\t"
+			THEAD_VLB_V_V0T0
+			"add		t0, t0, t4\n\t"
+			THEAD_VLB_V_V0T0
+			"add		t0, t0, t4\n\t"
+			THEAD_VLB_V_V0T0
+			: : "r" (datap) : "memory", "t0", "t4");
+	} else {
+		asm volatile (
+			".option push\n\t"
+			".option arch, +zve32x\n\t"
+			"vsetvli	%0, x0, e8, m8, ta, ma\n\t"
+			"vle8.v		v0, (%1)\n\t"
+			"add		%1, %1, %0\n\t"
+			"vle8.v		v8, (%1)\n\t"
+			"add		%1, %1, %0\n\t"
+			"vle8.v		v16, (%1)\n\t"
+			"add		%1, %1, %0\n\t"
+			"vle8.v		v24, (%1)\n\t"
+			".option pop\n\t"
+			: "=&r" (vl) : "r" (datap) : "memory");
+	}
 	__vstate_csr_restore(restore_from);
 	riscv_v_disable();
 }
 
 static inline void __riscv_v_vstate_discard(void)
 {
-	unsigned long vl, vtype_inval = 1UL << (BITS_PER_LONG - 1);
+	unsigned long vtype_inval = 1UL << (BITS_PER_LONG - 1);
 
 	riscv_v_enable();
+	if (has_xtheadvector())
+		asm volatile (THEAD_VSETVLI_X0X0E8M8D1);
+	else
+		asm volatile (
+			".option push\n\t"
+			".option arch, +v\n\t"
+			"vsetvli	x0, x0, e8, m8, ta, ma\n\t"
+			".option pop\n\t");
+
 	asm volatile (
 		".option push\n\t"
 		".option arch, +zve32x\n\t"
@@ -159,25 +282,25 @@  static inline void __riscv_v_vstate_discard(void)
 		"vmv.v.i	v8, -1\n\t"
 		"vmv.v.i	v16, -1\n\t"
 		"vmv.v.i	v24, -1\n\t"
-		"vsetvl		%0, x0, %1\n\t"
+		"vsetvl		x0, x0, %0\n\t"
 		".option pop\n\t"
-		: "=&r" (vl) : "r" (vtype_inval) : "memory");
+		: : "r" (vtype_inval));
+
 	riscv_v_disable();
 }
 
 static inline void riscv_v_vstate_discard(struct pt_regs *regs)
 {
-	if ((regs->status & SR_VS) == SR_VS_OFF)
-		return;
-
-	__riscv_v_vstate_discard();
-	__riscv_v_vstate_dirty(regs);
+	if (riscv_v_vstate_query(regs)) {
+		__riscv_v_vstate_discard();
+		__riscv_v_vstate_dirty(regs);
+	}
 }
 
 static inline void riscv_v_vstate_save(struct __riscv_v_ext_state *vstate,
 				       struct pt_regs *regs)
 {
-	if ((regs->status & SR_VS) == SR_VS_DIRTY) {
+	if (__riscv_v_vstate_check(regs->status, DIRTY)) {
 		__riscv_v_vstate_save(vstate, vstate->datap);
 		__riscv_v_vstate_clean(regs);
 	}
@@ -186,7 +309,7 @@  static inline void riscv_v_vstate_save(struct __riscv_v_ext_state *vstate,
 static inline void riscv_v_vstate_restore(struct __riscv_v_ext_state *vstate,
 					  struct pt_regs *regs)
 {
-	if ((regs->status & SR_VS) != SR_VS_OFF) {
+	if (riscv_v_vstate_query(regs)) {
 		__riscv_v_vstate_restore(vstate, vstate->datap);
 		__riscv_v_vstate_clean(regs);
 	}
@@ -195,7 +318,7 @@  static inline void riscv_v_vstate_restore(struct __riscv_v_ext_state *vstate,
 static inline void riscv_v_vstate_set_restore(struct task_struct *task,
 					      struct pt_regs *regs)
 {
-	if ((regs->status & SR_VS) != SR_VS_OFF) {
+	if (riscv_v_vstate_query(regs)) {
 		set_tsk_thread_flag(task, TIF_RISCV_V_DEFER_RESTORE);
 		riscv_v_vstate_on(regs);
 	}
@@ -268,6 +391,8 @@  struct pt_regs;
 
 static inline int riscv_v_setup_vsize(void) { return -EOPNOTSUPP; }
 static __always_inline bool has_vector(void) { return false; }
+static __always_inline bool has_xtheadvector_no_alternatives(void) { return false; }
+static __always_inline bool has_xtheadvector(void) { return false; }
 static inline bool riscv_v_first_use_handler(struct pt_regs *regs) { return false; }
 static inline bool riscv_v_vstate_query(struct pt_regs *regs) { return false; }
 static inline bool riscv_v_vstate_ctrl_user_allowed(void) { return false; }
diff --git a/arch/riscv/kernel/cpufeature.c b/arch/riscv/kernel/cpufeature.c
index 9340efd79af9..56b5054b8f86 100644
--- a/arch/riscv/kernel/cpufeature.c
+++ b/arch/riscv/kernel/cpufeature.c
@@ -867,8 +867,7 @@  static int __init riscv_fill_hwcap_from_ext_list(unsigned long *isa2hwcap)
 		riscv_fill_vendor_ext_list(cpu);
 	}
 
-	if (riscv_isa_vendor_extension_available(THEAD_VENDOR_ID, XTHEADVECTOR) &&
-	    has_thead_homogeneous_vlenb() < 0) {
+	if (has_xtheadvector_no_alternatives() && has_thead_homogeneous_vlenb() < 0) {
 		pr_warn("Unsupported heterogeneous vlenb detected, vector extension disabled.\n");
 		disable_xtheadvector();
 	}
@@ -925,7 +924,8 @@  void __init riscv_fill_hwcap(void)
 		elf_hwcap &= ~COMPAT_HWCAP_ISA_F;
 	}
 
-	if (__riscv_isa_extension_available(NULL, RISCV_ISA_EXT_ZVE32X)) {
+	if (__riscv_isa_extension_available(NULL, RISCV_ISA_EXT_ZVE32X) ||
+	    has_xtheadvector_no_alternatives()) {
 		/*
 		 * This cannot fail when called on the boot hart
 		 */
diff --git a/arch/riscv/kernel/kernel_mode_vector.c b/arch/riscv/kernel/kernel_mode_vector.c
index 6afe80c7f03a..99972a48e86b 100644
--- a/arch/riscv/kernel/kernel_mode_vector.c
+++ b/arch/riscv/kernel/kernel_mode_vector.c
@@ -143,7 +143,7 @@  static int riscv_v_start_kernel_context(bool *is_nested)
 
 	/* Transfer the ownership of V from user to kernel, then save */
 	riscv_v_start(RISCV_PREEMPT_V | RISCV_PREEMPT_V_DIRTY);
-	if ((task_pt_regs(current)->status & SR_VS) == SR_VS_DIRTY) {
+	if (__riscv_v_vstate_check(task_pt_regs(current)->status, DIRTY)) {
 		uvstate = &current->thread.vstate;
 		__riscv_v_vstate_save(uvstate, uvstate->datap);
 	}
@@ -160,7 +160,7 @@  asmlinkage void riscv_v_context_nesting_start(struct pt_regs *regs)
 		return;
 
 	depth = riscv_v_ctx_get_depth();
-	if (depth == 0 && (regs->status & SR_VS) == SR_VS_DIRTY)
+	if (depth == 0 && __riscv_v_vstate_check(regs->status, DIRTY))
 		riscv_preempt_v_set_dirty();
 
 	riscv_v_ctx_depth_inc();
@@ -208,7 +208,7 @@  void kernel_vector_begin(void)
 {
 	bool nested = false;
 
-	if (WARN_ON(!has_vector()))
+	if (WARN_ON(!(has_vector() || has_xtheadvector())))
 		return;
 
 	BUG_ON(!may_use_simd());
@@ -236,7 +236,7 @@  EXPORT_SYMBOL_GPL(kernel_vector_begin);
  */
 void kernel_vector_end(void)
 {
-	if (WARN_ON(!has_vector()))
+	if (WARN_ON(!(has_vector() || has_xtheadvector())))
 		return;
 
 	riscv_v_disable();
diff --git a/arch/riscv/kernel/process.c b/arch/riscv/kernel/process.c
index e4bc61c4e58a..191023decd16 100644
--- a/arch/riscv/kernel/process.c
+++ b/arch/riscv/kernel/process.c
@@ -176,7 +176,7 @@  void flush_thread(void)
 void arch_release_task_struct(struct task_struct *tsk)
 {
 	/* Free the vector context of datap. */
-	if (has_vector())
+	if (has_vector() || has_xtheadvector())
 		riscv_v_thread_free(tsk);
 }
 
@@ -222,7 +222,7 @@  int copy_thread(struct task_struct *p, const struct kernel_clone_args *args)
 		p->thread.s[0] = 0;
 	}
 	p->thread.riscv_v_flags = 0;
-	if (has_vector())
+	if (has_vector() || has_xtheadvector())
 		riscv_v_thread_alloc(p);
 	p->thread.ra = (unsigned long)ret_from_fork;
 	p->thread.sp = (unsigned long)childregs; /* kernel sp */
diff --git a/arch/riscv/kernel/signal.c b/arch/riscv/kernel/signal.c
index dcd282419456..94e905eea1de 100644
--- a/arch/riscv/kernel/signal.c
+++ b/arch/riscv/kernel/signal.c
@@ -189,7 +189,7 @@  static long restore_sigcontext(struct pt_regs *regs,
 
 			return 0;
 		case RISCV_V_MAGIC:
-			if (!has_vector() || !riscv_v_vstate_query(regs) ||
+			if (!(has_vector() || has_xtheadvector()) || !riscv_v_vstate_query(regs) ||
 			    size != riscv_v_sc_size)
 				return -EINVAL;
 
@@ -211,7 +211,7 @@  static size_t get_rt_frame_size(bool cal_all)
 
 	frame_size = sizeof(*frame);
 
-	if (has_vector()) {
+	if (has_vector() || has_xtheadvector()) {
 		if (cal_all || riscv_v_vstate_query(task_pt_regs(current)))
 			total_context_size += riscv_v_sc_size;
 	}
@@ -284,7 +284,7 @@  static long setup_sigcontext(struct rt_sigframe __user *frame,
 	if (has_fpu())
 		err |= save_fp_state(regs, &sc->sc_fpregs);
 	/* Save the vector state. */
-	if (has_vector() && riscv_v_vstate_query(regs))
+	if ((has_vector() || has_xtheadvector()) && riscv_v_vstate_query(regs))
 		err |= save_v_state(regs, (void __user **)&sc_ext_ptr);
 	/* Write zero to fp-reserved space and check it on restore_sigcontext */
 	err |= __put_user(0, &sc->sc_extdesc.reserved);
diff --git a/arch/riscv/kernel/vector.c b/arch/riscv/kernel/vector.c
index 9775d6a9c8ee..f3e1de574050 100644
--- a/arch/riscv/kernel/vector.c
+++ b/arch/riscv/kernel/vector.c
@@ -63,7 +63,7 @@  int riscv_v_setup_vsize(void)
 
 void __init riscv_v_setup_ctx_cache(void)
 {
-	if (!has_vector())
+	if (!(has_vector() || has_xtheadvector()))
 		return;
 
 	riscv_v_user_cachep = kmem_cache_create_usercopy("riscv_vector_ctx",
@@ -183,7 +183,7 @@  bool riscv_v_first_use_handler(struct pt_regs *regs)
 	u32 __user *epc = (u32 __user *)regs->epc;
 	u32 insn = (u32)regs->badaddr;
 
-	if (!has_vector())
+	if (!(has_vector() || has_xtheadvector()))
 		return false;
 
 	/* Do not handle if V is not supported, or disabled */
@@ -226,7 +226,7 @@  void riscv_v_vstate_ctrl_init(struct task_struct *tsk)
 	bool inherit;
 	int cur, next;
 
-	if (!has_vector())
+	if (!(has_vector() || has_xtheadvector()))
 		return;
 
 	next = riscv_v_ctrl_get_next(tsk);
@@ -248,7 +248,7 @@  void riscv_v_vstate_ctrl_init(struct task_struct *tsk)
 
 long riscv_v_vstate_ctrl_get_current(void)
 {
-	if (!has_vector())
+	if (!(has_vector() || has_xtheadvector()))
 		return -EINVAL;
 
 	return current->thread.vstate_ctrl & PR_RISCV_V_VSTATE_CTRL_MASK;
@@ -259,7 +259,7 @@  long riscv_v_vstate_ctrl_set_current(unsigned long arg)
 	bool inherit;
 	int cur, next;
 
-	if (!has_vector())
+	if (!(has_vector() || has_xtheadvector()))
 		return -EINVAL;
 
 	if (arg & ~PR_RISCV_V_VSTATE_CTRL_MASK)
@@ -309,7 +309,7 @@  static struct ctl_table riscv_v_default_vstate_table[] = {
 
 static int __init riscv_v_sysctl_init(void)
 {
-	if (has_vector())
+	if (has_vector() || has_xtheadvector())
 		if (!register_sysctl("abi", riscv_v_default_vstate_table))
 			return -EINVAL;
 	return 0;