1/*
2 * Copyright IBM Corp. 1999, 2009
3 *
4 * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
5 */
6
7#ifndef __ASM_SWITCH_TO_H
8#define __ASM_SWITCH_TO_H
9
10#include <linux/thread_info.h>
11#include <asm/ptrace.h>
12
13extern struct task_struct *__switch_to(void *, void *);
14extern void update_cr_regs(struct task_struct *task);
15
16static inline int test_fp_ctl(u32 fpc)
17{
18	u32 orig_fpc;
19	int rc;
20
21	asm volatile(
22		"	efpc    %1\n"
23		"	sfpc	%2\n"
24		"0:	sfpc	%1\n"
25		"	la	%0,0\n"
26		"1:\n"
27		EX_TABLE(0b,1b)
28		: "=d" (rc), "=d" (orig_fpc)
29		: "d" (fpc), "0" (-EINVAL));
30	return rc;
31}
32
33static inline void save_fp_ctl(u32 *fpc)
34{
35	asm volatile(
36		"       stfpc   %0\n"
37		: "+Q" (*fpc));
38}
39
40static inline int restore_fp_ctl(u32 *fpc)
41{
42	int rc;
43
44	asm volatile(
45		"	lfpc    %1\n"
46		"0:	la	%0,0\n"
47		"1:\n"
48		EX_TABLE(0b,1b)
49		: "=d" (rc) : "Q" (*fpc), "0" (-EINVAL));
50	return rc;
51}
52
53static inline void save_fp_regs(freg_t *fprs)
54{
55	asm volatile("std 0,%0" : "=Q" (fprs[0]));
56	asm volatile("std 2,%0" : "=Q" (fprs[2]));
57	asm volatile("std 4,%0" : "=Q" (fprs[4]));
58	asm volatile("std 6,%0" : "=Q" (fprs[6]));
59	asm volatile("std 1,%0" : "=Q" (fprs[1]));
60	asm volatile("std 3,%0" : "=Q" (fprs[3]));
61	asm volatile("std 5,%0" : "=Q" (fprs[5]));
62	asm volatile("std 7,%0" : "=Q" (fprs[7]));
63	asm volatile("std 8,%0" : "=Q" (fprs[8]));
64	asm volatile("std 9,%0" : "=Q" (fprs[9]));
65	asm volatile("std 10,%0" : "=Q" (fprs[10]));
66	asm volatile("std 11,%0" : "=Q" (fprs[11]));
67	asm volatile("std 12,%0" : "=Q" (fprs[12]));
68	asm volatile("std 13,%0" : "=Q" (fprs[13]));
69	asm volatile("std 14,%0" : "=Q" (fprs[14]));
70	asm volatile("std 15,%0" : "=Q" (fprs[15]));
71}
72
73static inline void restore_fp_regs(freg_t *fprs)
74{
75	asm volatile("ld 0,%0" : : "Q" (fprs[0]));
76	asm volatile("ld 2,%0" : : "Q" (fprs[2]));
77	asm volatile("ld 4,%0" : : "Q" (fprs[4]));
78	asm volatile("ld 6,%0" : : "Q" (fprs[6]));
79	asm volatile("ld 1,%0" : : "Q" (fprs[1]));
80	asm volatile("ld 3,%0" : : "Q" (fprs[3]));
81	asm volatile("ld 5,%0" : : "Q" (fprs[5]));
82	asm volatile("ld 7,%0" : : "Q" (fprs[7]));
83	asm volatile("ld 8,%0" : : "Q" (fprs[8]));
84	asm volatile("ld 9,%0" : : "Q" (fprs[9]));
85	asm volatile("ld 10,%0" : : "Q" (fprs[10]));
86	asm volatile("ld 11,%0" : : "Q" (fprs[11]));
87	asm volatile("ld 12,%0" : : "Q" (fprs[12]));
88	asm volatile("ld 13,%0" : : "Q" (fprs[13]));
89	asm volatile("ld 14,%0" : : "Q" (fprs[14]));
90	asm volatile("ld 15,%0" : : "Q" (fprs[15]));
91}
92
93static inline void save_vx_regs(__vector128 *vxrs)
94{
95	typedef struct { __vector128 _[__NUM_VXRS]; } addrtype;
96
97	asm volatile(
98		"	la	1,%0\n"
99		"	.word	0xe70f,0x1000,0x003e\n"	/* vstm 0,15,0(1) */
100		"	.word	0xe70f,0x1100,0x0c3e\n"	/* vstm 16,31,256(1) */
101		: "=Q" (*(addrtype *) vxrs) : : "1");
102}
103
104static inline void save_vx_regs_safe(__vector128 *vxrs)
105{
106	unsigned long cr0, flags;
107
108	flags = arch_local_irq_save();
109	__ctl_store(cr0, 0, 0);
110	__ctl_set_bit(0, 17);
111	__ctl_set_bit(0, 18);
112	save_vx_regs(vxrs);
113	__ctl_load(cr0, 0, 0);
114	arch_local_irq_restore(flags);
115}
116
117static inline void restore_vx_regs(__vector128 *vxrs)
118{
119	typedef struct { __vector128 _[__NUM_VXRS]; } addrtype;
120
121	asm volatile(
122		"	la	1,%0\n"
123		"	.word	0xe70f,0x1000,0x0036\n"	/* vlm 0,15,0(1) */
124		"	.word	0xe70f,0x1100,0x0c36\n"	/* vlm 16,31,256(1) */
125		: : "Q" (*(addrtype *) vxrs) : "1");
126}
127
128static inline void save_fp_vx_regs(struct task_struct *task)
129{
130	if (task->thread.vxrs)
131		save_vx_regs(task->thread.vxrs);
132	else
133		save_fp_regs(task->thread.fp_regs.fprs);
134}
135
136static inline void restore_fp_vx_regs(struct task_struct *task)
137{
138	if (task->thread.vxrs)
139		restore_vx_regs(task->thread.vxrs);
140	else
141		restore_fp_regs(task->thread.fp_regs.fprs);
142}
143
144static inline void save_access_regs(unsigned int *acrs)
145{
146	typedef struct { int _[NUM_ACRS]; } acrstype;
147
148	asm volatile("stam 0,15,%0" : "=Q" (*(acrstype *)acrs));
149}
150
151static inline void restore_access_regs(unsigned int *acrs)
152{
153	typedef struct { int _[NUM_ACRS]; } acrstype;
154
155	asm volatile("lam 0,15,%0" : : "Q" (*(acrstype *)acrs));
156}
157
158#define switch_to(prev,next,last) do {					\
159	if (prev->mm) {							\
160		save_fp_ctl(&prev->thread.fp_regs.fpc);			\
161		save_fp_vx_regs(prev);					\
162		save_access_regs(&prev->thread.acrs[0]);		\
163		save_ri_cb(prev->thread.ri_cb);				\
164	}								\
165	if (next->mm) {							\
166		update_cr_regs(next);					\
167		restore_fp_ctl(&next->thread.fp_regs.fpc);		\
168		restore_fp_vx_regs(next);				\
169		restore_access_regs(&next->thread.acrs[0]);		\
170		restore_ri_cb(next->thread.ri_cb, prev->thread.ri_cb);	\
171	}								\
172	prev = __switch_to(prev,next);					\
173} while (0)
174
175#endif /* __ASM_SWITCH_TO_H */
176