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	if (!MACHINE_HAS_IEEE)
22		return 0;
23
24	asm volatile(
25		"	efpc    %1\n"
26		"	sfpc	%2\n"
27		"0:	sfpc	%1\n"
28		"	la	%0,0\n"
29		"1:\n"
30		EX_TABLE(0b,1b)
31		: "=d" (rc), "=d" (orig_fpc)
32		: "d" (fpc), "0" (-EINVAL));
33	return rc;
34}
35
36static inline void save_fp_ctl(u32 *fpc)
37{
38	if (!MACHINE_HAS_IEEE)
39		return;
40
41	asm volatile(
42		"       stfpc   %0\n"
43		: "+Q" (*fpc));
44}
45
46static inline int restore_fp_ctl(u32 *fpc)
47{
48	int rc;
49
50	if (!MACHINE_HAS_IEEE)
51		return 0;
52
53	asm volatile(
54		"	lfpc    %1\n"
55		"0:	la	%0,0\n"
56		"1:\n"
57		EX_TABLE(0b,1b)
58		: "=d" (rc) : "Q" (*fpc), "0" (-EINVAL));
59	return rc;
60}
61
62static inline void save_fp_regs(freg_t *fprs)
63{
64	asm volatile("std 0,%0" : "=Q" (fprs[0]));
65	asm volatile("std 2,%0" : "=Q" (fprs[2]));
66	asm volatile("std 4,%0" : "=Q" (fprs[4]));
67	asm volatile("std 6,%0" : "=Q" (fprs[6]));
68	if (!MACHINE_HAS_IEEE)
69		return;
70	asm volatile("std 1,%0" : "=Q" (fprs[1]));
71	asm volatile("std 3,%0" : "=Q" (fprs[3]));
72	asm volatile("std 5,%0" : "=Q" (fprs[5]));
73	asm volatile("std 7,%0" : "=Q" (fprs[7]));
74	asm volatile("std 8,%0" : "=Q" (fprs[8]));
75	asm volatile("std 9,%0" : "=Q" (fprs[9]));
76	asm volatile("std 10,%0" : "=Q" (fprs[10]));
77	asm volatile("std 11,%0" : "=Q" (fprs[11]));
78	asm volatile("std 12,%0" : "=Q" (fprs[12]));
79	asm volatile("std 13,%0" : "=Q" (fprs[13]));
80	asm volatile("std 14,%0" : "=Q" (fprs[14]));
81	asm volatile("std 15,%0" : "=Q" (fprs[15]));
82}
83
84static inline void restore_fp_regs(freg_t *fprs)
85{
86	asm volatile("ld 0,%0" : : "Q" (fprs[0]));
87	asm volatile("ld 2,%0" : : "Q" (fprs[2]));
88	asm volatile("ld 4,%0" : : "Q" (fprs[4]));
89	asm volatile("ld 6,%0" : : "Q" (fprs[6]));
90	if (!MACHINE_HAS_IEEE)
91		return;
92	asm volatile("ld 1,%0" : : "Q" (fprs[1]));
93	asm volatile("ld 3,%0" : : "Q" (fprs[3]));
94	asm volatile("ld 5,%0" : : "Q" (fprs[5]));
95	asm volatile("ld 7,%0" : : "Q" (fprs[7]));
96	asm volatile("ld 8,%0" : : "Q" (fprs[8]));
97	asm volatile("ld 9,%0" : : "Q" (fprs[9]));
98	asm volatile("ld 10,%0" : : "Q" (fprs[10]));
99	asm volatile("ld 11,%0" : : "Q" (fprs[11]));
100	asm volatile("ld 12,%0" : : "Q" (fprs[12]));
101	asm volatile("ld 13,%0" : : "Q" (fprs[13]));
102	asm volatile("ld 14,%0" : : "Q" (fprs[14]));
103	asm volatile("ld 15,%0" : : "Q" (fprs[15]));
104}
105
106static inline void save_vx_regs(__vector128 *vxrs)
107{
108	typedef struct { __vector128 _[__NUM_VXRS]; } addrtype;
109
110	asm volatile(
111		"	la	1,%0\n"
112		"	.word	0xe70f,0x1000,0x003e\n"	/* vstm 0,15,0(1) */
113		"	.word	0xe70f,0x1100,0x0c3e\n"	/* vstm 16,31,256(1) */
114		: "=Q" (*(addrtype *) vxrs) : : "1");
115}
116
117static inline void save_vx_regs_safe(__vector128 *vxrs)
118{
119	unsigned long cr0, flags;
120
121	flags = arch_local_irq_save();
122	__ctl_store(cr0, 0, 0);
123	__ctl_set_bit(0, 17);
124	__ctl_set_bit(0, 18);
125	save_vx_regs(vxrs);
126	__ctl_load(cr0, 0, 0);
127	arch_local_irq_restore(flags);
128}
129
130static inline void restore_vx_regs(__vector128 *vxrs)
131{
132	typedef struct { __vector128 _[__NUM_VXRS]; } addrtype;
133
134	asm volatile(
135		"	la	1,%0\n"
136		"	.word	0xe70f,0x1000,0x0036\n"	/* vlm 0,15,0(1) */
137		"	.word	0xe70f,0x1100,0x0c36\n"	/* vlm 16,31,256(1) */
138		: : "Q" (*(addrtype *) vxrs) : "1");
139}
140
141static inline void save_fp_vx_regs(struct task_struct *task)
142{
143#ifdef CONFIG_64BIT
144	if (task->thread.vxrs)
145		save_vx_regs(task->thread.vxrs);
146	else
147#endif
148	save_fp_regs(task->thread.fp_regs.fprs);
149}
150
151static inline void restore_fp_vx_regs(struct task_struct *task)
152{
153#ifdef CONFIG_64BIT
154	if (task->thread.vxrs)
155		restore_vx_regs(task->thread.vxrs);
156	else
157#endif
158	restore_fp_regs(task->thread.fp_regs.fprs);
159}
160
161static inline void save_access_regs(unsigned int *acrs)
162{
163	typedef struct { int _[NUM_ACRS]; } acrstype;
164
165	asm volatile("stam 0,15,%0" : "=Q" (*(acrstype *)acrs));
166}
167
168static inline void restore_access_regs(unsigned int *acrs)
169{
170	typedef struct { int _[NUM_ACRS]; } acrstype;
171
172	asm volatile("lam 0,15,%0" : : "Q" (*(acrstype *)acrs));
173}
174
175#define switch_to(prev,next,last) do {					\
176	if (prev->mm) {							\
177		save_fp_ctl(&prev->thread.fp_regs.fpc);			\
178		save_fp_vx_regs(prev);					\
179		save_access_regs(&prev->thread.acrs[0]);		\
180		save_ri_cb(prev->thread.ri_cb);				\
181	}								\
182	if (next->mm) {							\
183		update_cr_regs(next);					\
184		restore_fp_ctl(&next->thread.fp_regs.fpc);		\
185		restore_fp_vx_regs(next);				\
186		restore_access_regs(&next->thread.acrs[0]);		\
187		restore_ri_cb(next->thread.ri_cb, prev->thread.ri_cb);	\
188	}								\
189	prev = __switch_to(prev,next);					\
190} while (0)
191
192#endif /* __ASM_SWITCH_TO_H */
193