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Diffstat (limited to '')
-rw-r--r-- | arch/loongarch/include/asm/fpu.h | 318 |
1 files changed, 318 insertions, 0 deletions
diff --git a/arch/loongarch/include/asm/fpu.h b/arch/loongarch/include/asm/fpu.h new file mode 100644 index 0000000000..c2d8962fda --- /dev/null +++ b/arch/loongarch/include/asm/fpu.h @@ -0,0 +1,318 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Author: Huacai Chen <chenhuacai@loongson.cn> + * Copyright (C) 2020-2022 Loongson Technology Corporation Limited + */ +#ifndef _ASM_FPU_H +#define _ASM_FPU_H + +#include <linux/sched.h> +#include <linux/sched/task_stack.h> +#include <linux/ptrace.h> +#include <linux/thread_info.h> +#include <linux/bitops.h> + +#include <asm/cpu.h> +#include <asm/cpu-features.h> +#include <asm/current.h> +#include <asm/loongarch.h> +#include <asm/processor.h> +#include <asm/ptrace.h> + +struct sigcontext; + +extern void kernel_fpu_begin(void); +extern void kernel_fpu_end(void); + +extern void _init_fpu(unsigned int); +extern void _save_fp(struct loongarch_fpu *); +extern void _restore_fp(struct loongarch_fpu *); + +extern void _save_lsx(struct loongarch_fpu *fpu); +extern void _restore_lsx(struct loongarch_fpu *fpu); +extern void _init_lsx_upper(void); +extern void _restore_lsx_upper(struct loongarch_fpu *fpu); + +extern void _save_lasx(struct loongarch_fpu *fpu); +extern void _restore_lasx(struct loongarch_fpu *fpu); +extern void _init_lasx_upper(void); +extern void _restore_lasx_upper(struct loongarch_fpu *fpu); + +static inline void enable_lsx(void); +static inline void disable_lsx(void); +static inline void save_lsx(struct task_struct *t); +static inline void restore_lsx(struct task_struct *t); + +static inline void enable_lasx(void); +static inline void disable_lasx(void); +static inline void save_lasx(struct task_struct *t); +static inline void restore_lasx(struct task_struct *t); + +/* + * Mask the FCSR Cause bits according to the Enable bits, observing + * that Unimplemented is always enabled. + */ +static inline unsigned long mask_fcsr_x(unsigned long fcsr) +{ + return fcsr & ((fcsr & FPU_CSR_ALL_E) << + (ffs(FPU_CSR_ALL_X) - ffs(FPU_CSR_ALL_E))); +} + +static inline int is_fp_enabled(void) +{ + return (csr_read32(LOONGARCH_CSR_EUEN) & CSR_EUEN_FPEN) ? + 1 : 0; +} + +static inline int is_lsx_enabled(void) +{ + if (!cpu_has_lsx) + return 0; + + return (csr_read32(LOONGARCH_CSR_EUEN) & CSR_EUEN_LSXEN) ? + 1 : 0; +} + +static inline int is_lasx_enabled(void) +{ + if (!cpu_has_lasx) + return 0; + + return (csr_read32(LOONGARCH_CSR_EUEN) & CSR_EUEN_LASXEN) ? + 1 : 0; +} + +static inline int is_simd_enabled(void) +{ + return is_lsx_enabled() | is_lasx_enabled(); +} + +#define enable_fpu() set_csr_euen(CSR_EUEN_FPEN) + +#define disable_fpu() clear_csr_euen(CSR_EUEN_FPEN) + +#define clear_fpu_owner() clear_thread_flag(TIF_USEDFPU) + +static inline int is_fpu_owner(void) +{ + return test_thread_flag(TIF_USEDFPU); +} + +static inline void __own_fpu(void) +{ + enable_fpu(); + set_thread_flag(TIF_USEDFPU); + KSTK_EUEN(current) |= CSR_EUEN_FPEN; +} + +static inline void own_fpu_inatomic(int restore) +{ + if (cpu_has_fpu && !is_fpu_owner()) { + __own_fpu(); + if (restore) + _restore_fp(¤t->thread.fpu); + } +} + +static inline void own_fpu(int restore) +{ + preempt_disable(); + own_fpu_inatomic(restore); + preempt_enable(); +} + +static inline void lose_fpu_inatomic(int save, struct task_struct *tsk) +{ + if (is_fpu_owner()) { + if (!is_simd_enabled()) { + if (save) + _save_fp(&tsk->thread.fpu); + disable_fpu(); + } else { + if (save) { + if (!is_lasx_enabled()) + save_lsx(tsk); + else + save_lasx(tsk); + } + disable_fpu(); + disable_lsx(); + disable_lasx(); + clear_tsk_thread_flag(tsk, TIF_USEDSIMD); + } + clear_tsk_thread_flag(tsk, TIF_USEDFPU); + } + KSTK_EUEN(tsk) &= ~(CSR_EUEN_FPEN | CSR_EUEN_LSXEN | CSR_EUEN_LASXEN); +} + +static inline void lose_fpu(int save) +{ + preempt_disable(); + lose_fpu_inatomic(save, current); + preempt_enable(); +} + +static inline void init_fpu(void) +{ + unsigned int fcsr = current->thread.fpu.fcsr; + + __own_fpu(); + _init_fpu(fcsr); + set_used_math(); +} + +static inline void save_fp(struct task_struct *tsk) +{ + if (cpu_has_fpu) + _save_fp(&tsk->thread.fpu); +} + +static inline void restore_fp(struct task_struct *tsk) +{ + if (cpu_has_fpu) + _restore_fp(&tsk->thread.fpu); +} + +static inline void save_fpu_regs(struct task_struct *tsk) +{ + unsigned int euen; + + if (tsk == current) { + preempt_disable(); + + euen = csr_read32(LOONGARCH_CSR_EUEN); + +#ifdef CONFIG_CPU_HAS_LASX + if (euen & CSR_EUEN_LASXEN) + _save_lasx(¤t->thread.fpu); + else +#endif +#ifdef CONFIG_CPU_HAS_LSX + if (euen & CSR_EUEN_LSXEN) + _save_lsx(¤t->thread.fpu); + else +#endif + if (euen & CSR_EUEN_FPEN) + _save_fp(¤t->thread.fpu); + + preempt_enable(); + } +} + +static inline int is_simd_owner(void) +{ + return test_thread_flag(TIF_USEDSIMD); +} + +#ifdef CONFIG_CPU_HAS_LSX + +static inline void enable_lsx(void) +{ + if (cpu_has_lsx) + csr_xchg32(CSR_EUEN_LSXEN, CSR_EUEN_LSXEN, LOONGARCH_CSR_EUEN); +} + +static inline void disable_lsx(void) +{ + if (cpu_has_lsx) + csr_xchg32(0, CSR_EUEN_LSXEN, LOONGARCH_CSR_EUEN); +} + +static inline void save_lsx(struct task_struct *t) +{ + if (cpu_has_lsx) + _save_lsx(&t->thread.fpu); +} + +static inline void restore_lsx(struct task_struct *t) +{ + if (cpu_has_lsx) + _restore_lsx(&t->thread.fpu); +} + +static inline void init_lsx_upper(void) +{ + if (cpu_has_lsx) + _init_lsx_upper(); +} + +static inline void restore_lsx_upper(struct task_struct *t) +{ + if (cpu_has_lsx) + _restore_lsx_upper(&t->thread.fpu); +} + +#else +static inline void enable_lsx(void) {} +static inline void disable_lsx(void) {} +static inline void save_lsx(struct task_struct *t) {} +static inline void restore_lsx(struct task_struct *t) {} +static inline void init_lsx_upper(void) {} +static inline void restore_lsx_upper(struct task_struct *t) {} +#endif + +#ifdef CONFIG_CPU_HAS_LASX + +static inline void enable_lasx(void) +{ + + if (cpu_has_lasx) + csr_xchg32(CSR_EUEN_LASXEN, CSR_EUEN_LASXEN, LOONGARCH_CSR_EUEN); +} + +static inline void disable_lasx(void) +{ + if (cpu_has_lasx) + csr_xchg32(0, CSR_EUEN_LASXEN, LOONGARCH_CSR_EUEN); +} + +static inline void save_lasx(struct task_struct *t) +{ + if (cpu_has_lasx) + _save_lasx(&t->thread.fpu); +} + +static inline void restore_lasx(struct task_struct *t) +{ + if (cpu_has_lasx) + _restore_lasx(&t->thread.fpu); +} + +static inline void init_lasx_upper(void) +{ + if (cpu_has_lasx) + _init_lasx_upper(); +} + +static inline void restore_lasx_upper(struct task_struct *t) +{ + if (cpu_has_lasx) + _restore_lasx_upper(&t->thread.fpu); +} + +#else +static inline void enable_lasx(void) {} +static inline void disable_lasx(void) {} +static inline void save_lasx(struct task_struct *t) {} +static inline void restore_lasx(struct task_struct *t) {} +static inline void init_lasx_upper(void) {} +static inline void restore_lasx_upper(struct task_struct *t) {} +#endif + +static inline int thread_lsx_context_live(void) +{ + if (!cpu_has_lsx) + return 0; + + return test_thread_flag(TIF_LSX_CTX_LIVE); +} + +static inline int thread_lasx_context_live(void) +{ + if (!cpu_has_lasx) + return 0; + + return test_thread_flag(TIF_LASX_CTX_LIVE); +} + +#endif /* _ASM_FPU_H */ |