5c7dd7acc3
repo: https://github.com/T-head-Semi/linux commit: b1313fe517ca3703119dcc99ef3bbf75ab42bcfb Change-Id: I6cbb35294024ea3a66140e311f4bb705fd7fd626
127 lines
3.1 KiB
C
127 lines
3.1 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
/* Copyright (C) 2005-2018 Andes Technology Corporation */
|
|
|
|
#ifndef __ASM_NDS32_FPU_H
|
|
#define __ASM_NDS32_FPU_H
|
|
|
|
#if IS_ENABLED(CONFIG_FPU)
|
|
#ifndef __ASSEMBLY__
|
|
#include <linux/sched/task_stack.h>
|
|
#include <linux/preempt.h>
|
|
#include <asm/ptrace.h>
|
|
|
|
extern bool has_fpu;
|
|
|
|
extern void save_fpu(struct task_struct *__tsk);
|
|
extern void load_fpu(const struct fpu_struct *fpregs);
|
|
extern bool do_fpu_exception(unsigned int subtype, struct pt_regs *regs);
|
|
extern int do_fpuemu(struct pt_regs *regs, struct fpu_struct *fpu);
|
|
|
|
#define test_tsk_fpu(regs) (regs->fucop_ctl & FUCOP_CTL_mskCP0EN)
|
|
|
|
/*
|
|
* Initially load the FPU with signalling NANS. This bit pattern
|
|
* has the property that no matter whether considered as single or as
|
|
* double precision, it still represents a signalling NAN.
|
|
*/
|
|
|
|
#define sNAN64 0xFFFFFFFFFFFFFFFFULL
|
|
#define sNAN32 0xFFFFFFFFUL
|
|
|
|
#if IS_ENABLED(CONFIG_SUPPORT_DENORMAL_ARITHMETIC)
|
|
/*
|
|
* Denormalized number is unsupported by nds32 FPU. Hence the operation
|
|
* is treated as underflow cases when the final result is a denormalized
|
|
* number. To enhance precision, underflow exception trap should be
|
|
* enabled by default and kerenl will re-execute it by fpu emulator
|
|
* when getting underflow exception.
|
|
*/
|
|
#define FPCSR_INIT (FPCSR_mskUDFE | FPCSR_mskIEXE)
|
|
#else
|
|
#define FPCSR_INIT 0x0UL
|
|
#endif
|
|
|
|
extern const struct fpu_struct init_fpuregs;
|
|
|
|
static inline void disable_ptreg_fpu(struct pt_regs *regs)
|
|
{
|
|
regs->fucop_ctl &= ~FUCOP_CTL_mskCP0EN;
|
|
}
|
|
|
|
static inline void enable_ptreg_fpu(struct pt_regs *regs)
|
|
{
|
|
regs->fucop_ctl |= FUCOP_CTL_mskCP0EN;
|
|
}
|
|
|
|
static inline void enable_fpu(void)
|
|
{
|
|
unsigned long fucop_ctl;
|
|
|
|
fucop_ctl = __nds32__mfsr(NDS32_SR_FUCOP_CTL) | FUCOP_CTL_mskCP0EN;
|
|
__nds32__mtsr(fucop_ctl, NDS32_SR_FUCOP_CTL);
|
|
__nds32__isb();
|
|
}
|
|
|
|
static inline void disable_fpu(void)
|
|
{
|
|
unsigned long fucop_ctl;
|
|
|
|
fucop_ctl = __nds32__mfsr(NDS32_SR_FUCOP_CTL) & ~FUCOP_CTL_mskCP0EN;
|
|
__nds32__mtsr(fucop_ctl, NDS32_SR_FUCOP_CTL);
|
|
__nds32__isb();
|
|
}
|
|
|
|
static inline void lose_fpu(void)
|
|
{
|
|
preempt_disable();
|
|
#if IS_ENABLED(CONFIG_LAZY_FPU)
|
|
if (last_task_used_math == current) {
|
|
last_task_used_math = NULL;
|
|
#else
|
|
if (test_tsk_fpu(task_pt_regs(current))) {
|
|
#endif
|
|
save_fpu(current);
|
|
}
|
|
disable_ptreg_fpu(task_pt_regs(current));
|
|
preempt_enable();
|
|
}
|
|
|
|
static inline void own_fpu(void)
|
|
{
|
|
preempt_disable();
|
|
#if IS_ENABLED(CONFIG_LAZY_FPU)
|
|
if (last_task_used_math != current) {
|
|
if (last_task_used_math != NULL)
|
|
save_fpu(last_task_used_math);
|
|
load_fpu(¤t->thread.fpu);
|
|
last_task_used_math = current;
|
|
}
|
|
#else
|
|
if (!test_tsk_fpu(task_pt_regs(current))) {
|
|
load_fpu(¤t->thread.fpu);
|
|
}
|
|
#endif
|
|
enable_ptreg_fpu(task_pt_regs(current));
|
|
preempt_enable();
|
|
}
|
|
|
|
#if !IS_ENABLED(CONFIG_LAZY_FPU)
|
|
static inline void unlazy_fpu(struct task_struct *tsk)
|
|
{
|
|
preempt_disable();
|
|
if (test_tsk_fpu(task_pt_regs(tsk)))
|
|
save_fpu(tsk);
|
|
preempt_enable();
|
|
}
|
|
#endif /* !CONFIG_LAZY_FPU */
|
|
static inline void clear_fpu(struct pt_regs *regs)
|
|
{
|
|
preempt_disable();
|
|
if (test_tsk_fpu(regs))
|
|
disable_ptreg_fpu(regs);
|
|
preempt_enable();
|
|
}
|
|
#endif /* CONFIG_FPU */
|
|
#endif /* __ASSEMBLY__ */
|
|
#endif /* __ASM_NDS32_FPU_H */
|