xref: /linux/arch/sh/include/asm/fpu.h (revision 8fa5723aa7e053d498336b48448b292fc2e0458b)
1 #ifndef __ASM_SH_FPU_H
2 #define __ASM_SH_FPU_H
3 
4 #ifndef __ASSEMBLY__
5 #include <linux/preempt.h>
6 #include <asm/ptrace.h>
7 
8 #ifdef CONFIG_SH_FPU
9 static inline void release_fpu(struct pt_regs *regs)
10 {
11 	regs->sr |= SR_FD;
12 }
13 
14 static inline void grab_fpu(struct pt_regs *regs)
15 {
16 	regs->sr &= ~SR_FD;
17 }
18 
19 struct task_struct;
20 
21 extern void save_fpu(struct task_struct *__tsk, struct pt_regs *regs);
22 #else
23 
24 #define release_fpu(regs)	do { } while (0)
25 #define grab_fpu(regs)		do { } while (0)
26 
27 static inline void save_fpu(struct task_struct *tsk, struct pt_regs *regs)
28 {
29 	clear_tsk_thread_flag(tsk, TIF_USEDFPU);
30 }
31 #endif
32 
33 struct user_regset;
34 
35 extern int do_fpu_inst(unsigned short, struct pt_regs *);
36 
37 extern int fpregs_get(struct task_struct *target,
38 		      const struct user_regset *regset,
39 		      unsigned int pos, unsigned int count,
40 		      void *kbuf, void __user *ubuf);
41 
42 static inline void unlazy_fpu(struct task_struct *tsk, struct pt_regs *regs)
43 {
44 	preempt_disable();
45 	if (test_tsk_thread_flag(tsk, TIF_USEDFPU))
46 		save_fpu(tsk, regs);
47 	preempt_enable();
48 }
49 
50 static inline void clear_fpu(struct task_struct *tsk, struct pt_regs *regs)
51 {
52 	preempt_disable();
53 	if (test_tsk_thread_flag(tsk, TIF_USEDFPU)) {
54 		clear_tsk_thread_flag(tsk, TIF_USEDFPU);
55 		release_fpu(regs);
56 	}
57 	preempt_enable();
58 }
59 
60 static inline int init_fpu(struct task_struct *tsk)
61 {
62 	if (tsk_used_math(tsk)) {
63 		if ((boot_cpu_data.flags & CPU_HAS_FPU) && tsk == current)
64 			unlazy_fpu(tsk, task_pt_regs(tsk));
65 		return 0;
66 	}
67 
68 	set_stopped_child_used_math(tsk);
69 	return 0;
70 }
71 
72 #endif /* __ASSEMBLY__ */
73 
74 #endif /* __ASM_SH_FPU_H */
75