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/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
* Copyright (C) 2020 SiFive
*/
#ifndef __ASM_RISCV_VECTOR_H
#define __ASM_RISCV_VECTOR_H
#include <linux/types.h>
#include <uapi/asm-generic/errno.h>
#ifdef CONFIG_RISCV_ISA_V
#include <linux/stringify.h>
#include <linux/sched.h>
#include <linux/sched/task_stack.h>
#include <asm/ptrace.h>
#include <asm/cpufeature.h>
#include <asm/csr.h>
#include <asm/asm.h>
extern unsigned long riscv_v_vsize;
int riscv_v_setup_vsize(void);
bool riscv_v_first_use_handler(struct pt_regs *regs);
void kernel_vector_begin(void);
void kernel_vector_end(void);
void get_cpu_vector_context(void);
void put_cpu_vector_context(void);
void riscv_v_thread_free(struct task_struct *tsk);
void __init riscv_v_setup_ctx_cache(void);
void riscv_v_thread_alloc(struct task_struct *tsk);
static inline u32 riscv_v_flags(void)
{
return READ_ONCE(current->thread.riscv_v_flags);
}
static __always_inline bool has_vector(void)
{
return riscv_has_extension_unlikely(RISCV_ISA_EXT_v);
}
static inline void __riscv_v_vstate_clean(struct pt_regs *regs)
{
regs->status = (regs->status & ~SR_VS) | SR_VS_CLEAN;
}
static inline void __riscv_v_vstate_dirty(struct pt_regs *regs)
{
regs->status = (regs->status & ~SR_VS) | SR_VS_DIRTY;
}
static inline void riscv_v_vstate_off(struct pt_regs *regs)
{
regs->status = (regs->status & ~SR_VS) | SR_VS_OFF;
}
static inline void riscv_v_vstate_on(struct pt_regs *regs)
{
regs->status = (regs->status & ~SR_VS) | SR_VS_INITIAL;
}
static inline bool riscv_v_vstate_query(struct pt_regs *regs)
{
return (regs->status & SR_VS) != 0;
}
static __always_inline void riscv_v_enable(void)
{
csr_set(CSR_SSTATUS, SR_VS);
}
static __always_inline void riscv_v_disable(void)
{
csr_clear(CSR_SSTATUS, SR_VS);
}
static __always_inline void __vstate_csr_save(struct __riscv_v_ext_state *dest)
{
asm volatile (
"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) : :);
}
static __always_inline void __vstate_csr_restore(struct __riscv_v_ext_state *src)
{
asm volatile (
".option push\n\t"
".option arch, +v\n\t"
"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) :);
}
static inline void __riscv_v_vstate_save(struct __riscv_v_ext_state *save_to,
void *datap)
{
unsigned long vl;
riscv_v_enable();
__vstate_csr_save(save_to);
asm volatile (
".option push\n\t"
".option arch, +v\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();
}
static inline void __riscv_v_vstate_restore(struct __riscv_v_ext_state *restore_from,
void *datap)
{
unsigned long vl;
riscv_v_enable();
asm volatile (
".option push\n\t"
".option arch, +v\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);
riscv_v_enable();
asm volatile (
".option push\n\t"
".option arch, +v\n\t"
"vsetvli %0, x0, e8, m8, ta, ma\n\t"
"vmv.v.i v0, -1\n\t"
"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"
".option pop\n\t"
: "=&r" (vl) : "r" (vtype_inval) : "memory");
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);
}
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) {
__riscv_v_vstate_save(vstate, vstate->datap);
__riscv_v_vstate_clean(regs);
}
}
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) {
__riscv_v_vstate_restore(vstate, vstate->datap);
__riscv_v_vstate_clean(regs);
}
}
static inline void riscv_v_vstate_set_restore(struct task_struct *task,
struct pt_regs *regs)
{
if ((regs->status & SR_VS) != SR_VS_OFF) {
set_tsk_thread_flag(task, TIF_RISCV_V_DEFER_RESTORE);
riscv_v_vstate_on(regs);
}
}
#ifdef CONFIG_RISCV_ISA_V_PREEMPTIVE
static inline bool riscv_preempt_v_dirty(struct task_struct *task)
{
return !!(task->thread.riscv_v_flags & RISCV_PREEMPT_V_DIRTY);
}
static inline bool riscv_preempt_v_restore(struct task_struct *task)
{
return !!(task->thread.riscv_v_flags & RISCV_PREEMPT_V_NEED_RESTORE);
}
static inline void riscv_preempt_v_clear_dirty(struct task_struct *task)
{
barrier();
task->thread.riscv_v_flags &= ~RISCV_PREEMPT_V_DIRTY;
}
static inline void riscv_preempt_v_set_restore(struct task_struct *task)
{
barrier();
task->thread.riscv_v_flags |= RISCV_PREEMPT_V_NEED_RESTORE;
}
static inline bool riscv_preempt_v_started(struct task_struct *task)
{
return !!(task->thread.riscv_v_flags & RISCV_PREEMPT_V);
}
#else /* !CONFIG_RISCV_ISA_V_PREEMPTIVE */
static inline bool riscv_preempt_v_dirty(struct task_struct *task) { return false; }
static inline bool riscv_preempt_v_restore(struct task_struct *task) { return false; }
static inline bool riscv_preempt_v_started(struct task_struct *task) { return false; }
#define riscv_preempt_v_clear_dirty(tsk) do {} while (0)
#define riscv_preempt_v_set_restore(tsk) do {} while (0)
#endif /* CONFIG_RISCV_ISA_V_PREEMPTIVE */
static inline void __switch_to_vector(struct task_struct *prev,
struct task_struct *next)
{
struct pt_regs *regs;
if (riscv_preempt_v_started(prev)) {
if (riscv_preempt_v_dirty(prev)) {
__riscv_v_vstate_save(&prev->thread.kernel_vstate,
prev->thread.kernel_vstate.datap);
riscv_preempt_v_clear_dirty(prev);
}
} else {
regs = task_pt_regs(prev);
riscv_v_vstate_save(&prev->thread.vstate, regs);
}
if (riscv_preempt_v_started(next))
riscv_preempt_v_set_restore(next);
else
riscv_v_vstate_set_restore(next, task_pt_regs(next));
}
void riscv_v_vstate_ctrl_init(struct task_struct *tsk);
bool riscv_v_vstate_ctrl_user_allowed(void);
#else /* ! CONFIG_RISCV_ISA_V */
struct pt_regs;
static inline int riscv_v_setup_vsize(void) { return -EOPNOTSUPP; }
static __always_inline bool has_vector(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; }
#define riscv_v_vsize (0)
#define riscv_v_vstate_discard(regs) do {} while (0)
#define riscv_v_vstate_save(vstate, regs) do {} while (0)
#define riscv_v_vstate_restore(vstate, regs) do {} while (0)
#define __switch_to_vector(__prev, __next) do {} while (0)
#define riscv_v_vstate_off(regs) do {} while (0)
#define riscv_v_vstate_on(regs) do {} while (0)
#define riscv_v_thread_free(tsk) do {} while (0)
#define riscv_v_setup_ctx_cache() do {} while (0)
#define riscv_v_thread_alloc(tsk) do {} while (0)
#endif /* CONFIG_RISCV_ISA_V */
#endif /* ! __ASM_RISCV_VECTOR_H */
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