| Message ID | 20240911-xtheadvector-v10-9-8d3930091246@rivosinc.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | riscv: Add support for xtheadvector | expand |
Hi Charlie, Charlie Jenkins <charlie@rivosinc.com> 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 <charlie@rivosinc.com> > Reviewed-by: Conor Dooley <conor.dooley@microchip.com> > --- > 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 = ¤t->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 > linux-riscv@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-riscv For the rest of this patch: Reviewed-by: Andy Chiu <andybnac@gmail.com> Thanks, Andy
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 = ¤t->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;