xref: /linux/arch/xtensa/include/asm/traps.h (revision b6ebbac51bedf9e98e837688bc838f400196da5e)
1 /*
2  * arch/xtensa/include/asm/traps.h
3  *
4  * This file is subject to the terms and conditions of the GNU General Public
5  * License.  See the file "COPYING" in the main directory of this archive
6  * for more details.
7  *
8  * Copyright (C) 2012 Tensilica Inc.
9  */
10 #ifndef _XTENSA_TRAPS_H
11 #define _XTENSA_TRAPS_H
12 
13 #include <asm/ptrace.h>
14 
15 /*
16  * handler must be either of the following:
17  *  void (*)(struct pt_regs *regs);
18  *  void (*)(struct pt_regs *regs, unsigned long exccause);
19  */
20 extern void * __init trap_set_handler(int cause, void *handler);
21 extern void do_unhandled(struct pt_regs *regs, unsigned long exccause);
22 void secondary_trap_init(void);
23 
24 static inline void spill_registers(void)
25 {
26 #if XCHAL_NUM_AREGS > 16
27 	__asm__ __volatile__ (
28 		"	call8	1f\n"
29 		"	_j	2f\n"
30 		"	retw\n"
31 		"	.align	4\n"
32 		"1:\n"
33 #if XCHAL_NUM_AREGS == 32
34 		"	_entry	a1, 32\n"
35 		"	addi	a8, a0, 3\n"
36 		"	_entry	a1, 16\n"
37 		"	mov	a12, a12\n"
38 		"	retw\n"
39 #else
40 		"	_entry	a1, 48\n"
41 		"	call12	1f\n"
42 		"	retw\n"
43 		"	.align	4\n"
44 		"1:\n"
45 		"	.rept	(" __stringify(XCHAL_NUM_AREGS) " - 16) / 12\n"
46 		"	_entry	a1, 48\n"
47 		"	mov	a12, a0\n"
48 		"	.endr\n"
49 		"	_entry	a1, 16\n"
50 #if XCHAL_NUM_AREGS % 12 == 0
51 		"	mov	a12, a12\n"
52 #elif XCHAL_NUM_AREGS % 12 == 4
53 		"	mov	a4, a4\n"
54 #elif XCHAL_NUM_AREGS % 12 == 8
55 		"	mov	a8, a8\n"
56 #endif
57 		"	retw\n"
58 #endif
59 		"2:\n"
60 		: : : "a8", "a9", "memory");
61 #else
62 	__asm__ __volatile__ (
63 		"	mov	a12, a12\n"
64 		: : : "memory");
65 #endif
66 }
67 
68 struct debug_table {
69 	/* Pointer to debug exception handler */
70 	void (*debug_exception)(void);
71 	/* Temporary register save area */
72 	unsigned long debug_save[1];
73 #ifdef CONFIG_HAVE_HW_BREAKPOINT
74 	/* Save area for DBREAKC registers */
75 	unsigned long dbreakc_save[XCHAL_NUM_DBREAK];
76 	/* Saved ICOUNT register */
77 	unsigned long icount_save;
78 	/* Saved ICOUNTLEVEL register */
79 	unsigned long icount_level_save;
80 #endif
81 };
82 
83 void debug_exception(void);
84 
85 #endif /* _XTENSA_TRAPS_H */
86