1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Copyright (C) 1999 Cort Dougan <cort@cs.nmt.edu>
4  */
5 #ifndef _ASM_POWERPC_SWITCH_TO_H
6 #define _ASM_POWERPC_SWITCH_TO_H
7 
8 #include <linux/sched.h>
9 #include <asm/reg.h>
10 
11 struct thread_struct;
12 struct task_struct;
13 struct pt_regs;
14 
15 extern struct task_struct *__switch_to(struct task_struct *,
16 	struct task_struct *);
17 #define switch_to(prev, next, last)	((last) = __switch_to((prev), (next)))
18 
19 extern struct task_struct *_switch(struct thread_struct *prev,
20 				   struct thread_struct *next);
21 
22 extern void switch_booke_debug_regs(struct debug_reg *new_debug);
23 
24 extern int emulate_altivec(struct pt_regs *);
25 
26 #ifdef CONFIG_PPC_BOOK3S_64
27 void restore_math(struct pt_regs *regs);
28 #else
restore_math(struct pt_regs * regs)29 static inline void restore_math(struct pt_regs *regs)
30 {
31 }
32 #endif
33 
34 void restore_tm_state(struct pt_regs *regs);
35 
36 extern void flush_all_to_thread(struct task_struct *);
37 extern void giveup_all(struct task_struct *);
38 
39 #ifdef CONFIG_PPC_FPU
40 extern void enable_kernel_fp(void);
41 extern void flush_fp_to_thread(struct task_struct *);
42 extern void giveup_fpu(struct task_struct *);
43 extern void save_fpu(struct task_struct *);
disable_kernel_fp(void)44 static inline void disable_kernel_fp(void)
45 {
46 	msr_check_and_clear(MSR_FP);
47 }
48 #else
save_fpu(struct task_struct * t)49 static inline void save_fpu(struct task_struct *t) { }
flush_fp_to_thread(struct task_struct * t)50 static inline void flush_fp_to_thread(struct task_struct *t) { }
51 #endif
52 
53 #ifdef CONFIG_ALTIVEC
54 extern void enable_kernel_altivec(void);
55 extern void flush_altivec_to_thread(struct task_struct *);
56 extern void giveup_altivec(struct task_struct *);
57 extern void save_altivec(struct task_struct *);
disable_kernel_altivec(void)58 static inline void disable_kernel_altivec(void)
59 {
60 	msr_check_and_clear(MSR_VEC);
61 }
62 #else
save_altivec(struct task_struct * t)63 static inline void save_altivec(struct task_struct *t) { }
__giveup_altivec(struct task_struct * t)64 static inline void __giveup_altivec(struct task_struct *t) { }
65 #endif
66 
67 #ifdef CONFIG_VSX
68 extern void enable_kernel_vsx(void);
69 extern void flush_vsx_to_thread(struct task_struct *);
disable_kernel_vsx(void)70 static inline void disable_kernel_vsx(void)
71 {
72 	msr_check_and_clear(MSR_FP|MSR_VEC|MSR_VSX);
73 }
74 #else
enable_kernel_vsx(void)75 static inline void enable_kernel_vsx(void)
76 {
77 	BUILD_BUG();
78 }
79 
disable_kernel_vsx(void)80 static inline void disable_kernel_vsx(void)
81 {
82 	BUILD_BUG();
83 }
84 #endif
85 
86 #ifdef CONFIG_SPE
87 extern void enable_kernel_spe(void);
88 extern void flush_spe_to_thread(struct task_struct *);
89 extern void giveup_spe(struct task_struct *);
90 extern void __giveup_spe(struct task_struct *);
disable_kernel_spe(void)91 static inline void disable_kernel_spe(void)
92 {
93 	msr_check_and_clear(MSR_SPE);
94 }
95 #else
__giveup_spe(struct task_struct * t)96 static inline void __giveup_spe(struct task_struct *t) { }
97 #endif
98 
clear_task_ebb(struct task_struct * t)99 static inline void clear_task_ebb(struct task_struct *t)
100 {
101 #ifdef CONFIG_PPC_BOOK3S_64
102     /* EBB perf events are not inherited, so clear all EBB state. */
103     t->thread.ebbrr = 0;
104     t->thread.ebbhr = 0;
105     t->thread.bescr = 0;
106     t->thread.mmcr2 = 0;
107     t->thread.mmcr0 = 0;
108     t->thread.siar = 0;
109     t->thread.sdar = 0;
110     t->thread.sier = 0;
111     t->thread.used_ebb = 0;
112 #endif
113 }
114 
115 extern int set_thread_tidr(struct task_struct *t);
116 
117 #endif /* _ASM_POWERPC_SWITCH_TO_H */
118