xref: /openbmc/linux/arch/sh/include/asm/switch_to_32.h (revision 55fd7e02)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __ASM_SH_SWITCH_TO_32_H
3 #define __ASM_SH_SWITCH_TO_32_H
4 
5 #ifdef CONFIG_SH_DSP
6 
7 #define is_dsp_enabled(tsk)						\
8 	(!!(tsk->thread.dsp_status.status & SR_DSP))
9 
10 #define __restore_dsp(tsk)						\
11 do {									\
12 	register u32 *__ts2 __asm__ ("r2") =				\
13 			(u32 *)&tsk->thread.dsp_status;			\
14 	__asm__ __volatile__ (						\
15 		".balign 4\n\t"						\
16 		"movs.l	@r2+, a0\n\t"					\
17 		"movs.l	@r2+, a1\n\t"					\
18 		"movs.l	@r2+, a0g\n\t"					\
19 		"movs.l	@r2+, a1g\n\t"					\
20 		"movs.l	@r2+, m0\n\t"					\
21 		"movs.l	@r2+, m1\n\t"					\
22 		"movs.l	@r2+, x0\n\t"					\
23 		"movs.l	@r2+, x1\n\t"					\
24 		"movs.l	@r2+, y0\n\t"					\
25 		"movs.l	@r2+, y1\n\t"					\
26 		"lds.l	@r2+, dsr\n\t"					\
27 		"ldc.l	@r2+, rs\n\t"					\
28 		"ldc.l	@r2+, re\n\t"					\
29 		"ldc.l	@r2+, mod\n\t"					\
30 		: : "r" (__ts2));					\
31 } while (0)
32 
33 #define __save_dsp(tsk)							\
34 do {									\
35 	register u32 *__ts2 __asm__ ("r2") =				\
36 			(u32 *)&tsk->thread.dsp_status + 14;		\
37 									\
38 	__asm__ __volatile__ (						\
39 		".balign 4\n\t"						\
40 		"stc.l	mod, @-r2\n\t"					\
41 		"stc.l	re, @-r2\n\t"					\
42 		"stc.l	rs, @-r2\n\t"					\
43 		"sts.l	dsr, @-r2\n\t"					\
44 		"movs.l	y1, @-r2\n\t"					\
45 		"movs.l	y0, @-r2\n\t"					\
46 		"movs.l	x1, @-r2\n\t"					\
47 		"movs.l	x0, @-r2\n\t"					\
48 		"movs.l	m1, @-r2\n\t"					\
49 		"movs.l	m0, @-r2\n\t"					\
50 		"movs.l	a1g, @-r2\n\t"					\
51 		"movs.l	a0g, @-r2\n\t"					\
52 		"movs.l	a1, @-r2\n\t"					\
53 		"movs.l	a0, @-r2\n\t"					\
54 		: : "r" (__ts2));					\
55 } while (0)
56 
57 #else
58 
59 #define is_dsp_enabled(tsk)	(0)
60 #define __save_dsp(tsk)		do { } while (0)
61 #define __restore_dsp(tsk)	do { } while (0)
62 #endif
63 
64 struct task_struct *__switch_to(struct task_struct *prev,
65 				struct task_struct *next);
66 
67 /*
68  *	switch_to() should switch tasks to task nr n, first
69  */
70 #define switch_to(prev, next, last)				\
71 do {								\
72 	register u32 *__ts1 __asm__ ("r1");			\
73 	register u32 *__ts2 __asm__ ("r2");			\
74 	register u32 *__ts4 __asm__ ("r4");			\
75 	register u32 *__ts5 __asm__ ("r5");			\
76 	register u32 *__ts6 __asm__ ("r6");			\
77 	register u32 __ts7 __asm__ ("r7");			\
78 	struct task_struct *__last;				\
79 								\
80 	if (is_dsp_enabled(prev))				\
81 		__save_dsp(prev);				\
82 	if (is_dsp_enabled(next))				\
83 		__restore_dsp(next);				\
84 								\
85 	__ts1 = (u32 *)&prev->thread.sp;			\
86 	__ts2 = (u32 *)&prev->thread.pc;			\
87 	__ts4 = (u32 *)prev;					\
88 	__ts5 = (u32 *)next;					\
89 	__ts6 = (u32 *)&next->thread.sp;			\
90 	__ts7 = next->thread.pc;				\
91 								\
92 	__asm__ __volatile__ (					\
93 		".balign 4\n\t"					\
94 		"stc.l	gbr, @-r15\n\t"				\
95 		"sts.l	pr, @-r15\n\t"				\
96 		"mov.l	r8, @-r15\n\t"				\
97 		"mov.l	r9, @-r15\n\t"				\
98 		"mov.l	r10, @-r15\n\t"				\
99 		"mov.l	r11, @-r15\n\t"				\
100 		"mov.l	r12, @-r15\n\t"				\
101 		"mov.l	r13, @-r15\n\t"				\
102 		"mov.l	r14, @-r15\n\t"				\
103 		"mov.l	r15, @r1\t! save SP\n\t"		\
104 		"mov.l	@r6, r15\t! change to new stack\n\t"	\
105 		"mova	1f, %0\n\t"				\
106 		"mov.l	%0, @r2\t! save PC\n\t"			\
107 		"mov.l	2f, %0\n\t"				\
108 		"jmp	@%0\t! call __switch_to\n\t"		\
109 		" lds	r7, pr\t!  with return to new PC\n\t"	\
110 		".balign	4\n"				\
111 		"2:\n\t"					\
112 		".long	__switch_to\n"				\
113 		"1:\n\t"					\
114 		"mov.l	@r15+, r14\n\t"				\
115 		"mov.l	@r15+, r13\n\t"				\
116 		"mov.l	@r15+, r12\n\t"				\
117 		"mov.l	@r15+, r11\n\t"				\
118 		"mov.l	@r15+, r10\n\t"				\
119 		"mov.l	@r15+, r9\n\t"				\
120 		"mov.l	@r15+, r8\n\t"				\
121 		"lds.l	@r15+, pr\n\t"				\
122 		"ldc.l	@r15+, gbr\n\t"				\
123 		: "=z" (__last)					\
124 		: "r" (__ts1), "r" (__ts2), "r" (__ts4),	\
125 		  "r" (__ts5), "r" (__ts6), "r" (__ts7)		\
126 		: "r3", "t");					\
127 								\
128 	last = __last;						\
129 } while (0)
130 
131 #endif /* __ASM_SH_SWITCH_TO_32_H */
132