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 typedef void xtensa_exception_handler(struct pt_regs *regs);
16
17 /*
18 * Per-CPU exception handling data structure.
19 * EXCSAVE1 points to it.
20 */
21 struct exc_table {
22 /* Kernel Stack */
23 void *kstk;
24 /* Double exception save area for a0 */
25 unsigned long double_save;
26 /* Fixup handler */
27 void *fixup;
28 /* For passing a parameter to fixup */
29 void *fixup_param;
30 #if XTENSA_HAVE_COPROCESSORS
31 /* Pointers to owner struct thread_info */
32 struct thread_info *coprocessor_owner[XCHAL_CP_MAX];
33 #endif
34 /* Fast user exception handlers */
35 void *fast_user_handler[EXCCAUSE_N];
36 /* Fast kernel exception handlers */
37 void *fast_kernel_handler[EXCCAUSE_N];
38 /* Default C-Handlers */
39 xtensa_exception_handler *default_handler[EXCCAUSE_N];
40 };
41
42 DECLARE_PER_CPU(struct exc_table, exc_table);
43
44 xtensa_exception_handler *
45 __init trap_set_handler(int cause, xtensa_exception_handler *handler);
46
47 asmlinkage void fast_illegal_instruction_user(void);
48 asmlinkage void fast_syscall_user(void);
49 asmlinkage void fast_alloca(void);
50 asmlinkage void fast_load_store(void);
51 asmlinkage void fast_unaligned(void);
52 asmlinkage void fast_second_level_miss(void);
53 asmlinkage void fast_store_prohibited(void);
54 asmlinkage void fast_coprocessor(void);
55
56 asmlinkage void kernel_exception(void);
57 asmlinkage void user_exception(void);
58 asmlinkage void system_call(struct pt_regs *regs);
59
60 void do_IRQ(int hwirq, struct pt_regs *regs);
61 void do_page_fault(struct pt_regs *regs);
62 void do_unhandled(struct pt_regs *regs);
63
64 /* Initialize minimal exc_table structure sufficient for basic paging */
early_trap_init(void)65 static inline void __init early_trap_init(void)
66 {
67 static struct exc_table init_exc_table __initdata = {
68 #ifdef CONFIG_XTENSA_LOAD_STORE
69 .fast_kernel_handler[EXCCAUSE_LOAD_STORE_ERROR] =
70 fast_load_store,
71 #endif
72 #ifdef CONFIG_MMU
73 .fast_kernel_handler[EXCCAUSE_DTLB_MISS] =
74 fast_second_level_miss,
75 #endif
76 };
77 xtensa_set_sr(&init_exc_table, excsave1);
78 }
79
80 void secondary_trap_init(void);
81
spill_registers(void)82 static inline void spill_registers(void)
83 {
84 #if defined(__XTENSA_WINDOWED_ABI__)
85 #if XCHAL_NUM_AREGS > 16
86 __asm__ __volatile__ (
87 " call8 1f\n"
88 " _j 2f\n"
89 " retw\n"
90 " .align 4\n"
91 "1:\n"
92 #if XCHAL_NUM_AREGS == 32
93 " _entry a1, 32\n"
94 " addi a8, a0, 3\n"
95 " _entry a1, 16\n"
96 " mov a12, a12\n"
97 " retw\n"
98 #else
99 " _entry a1, 48\n"
100 " call12 1f\n"
101 " retw\n"
102 " .align 4\n"
103 "1:\n"
104 " .rept (" __stringify(XCHAL_NUM_AREGS) " - 16) / 12\n"
105 " _entry a1, 48\n"
106 " mov a12, a0\n"
107 " .endr\n"
108 " _entry a1, 16\n"
109 #if XCHAL_NUM_AREGS % 12 == 0
110 " mov a12, a12\n"
111 #elif XCHAL_NUM_AREGS % 12 == 4
112 " mov a4, a4\n"
113 #elif XCHAL_NUM_AREGS % 12 == 8
114 " mov a8, a8\n"
115 #endif
116 " retw\n"
117 #endif
118 "2:\n"
119 : : : "a8", "a9", "memory");
120 #else
121 __asm__ __volatile__ (
122 " mov a12, a12\n"
123 : : : "memory");
124 #endif
125 #endif
126 }
127
128 struct debug_table {
129 /* Pointer to debug exception handler */
130 void (*debug_exception)(void);
131 /* Temporary register save area */
132 unsigned long debug_save[1];
133 #ifdef CONFIG_HAVE_HW_BREAKPOINT
134 /* Save area for DBREAKC registers */
135 unsigned long dbreakc_save[XCHAL_NUM_DBREAK];
136 /* Saved ICOUNT register */
137 unsigned long icount_save;
138 /* Saved ICOUNTLEVEL register */
139 unsigned long icount_level_save;
140 #endif
141 };
142
143 void debug_exception(void);
144
145 #endif /* _XTENSA_TRAPS_H */
146