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Commit | Line | Data |
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bce495d8 | 1 | #include <linux/init.h> |
1da177e4 LT |
2 | #include <linux/linkage.h> |
3 | ||
4 | #include <asm/assembler.h> | |
e6ae744d | 5 | #include <asm/asm-offsets.h> |
1da177e4 | 6 | #include <asm/errno.h> |
bce495d8 | 7 | #include <asm/thread_info.h> |
1da177e4 LT |
8 | |
9 | @ Bad Abort numbers | |
10 | @ ----------------- | |
11 | @ | |
12 | #define BAD_PREFETCH 0 | |
13 | #define BAD_DATA 1 | |
14 | #define BAD_ADDREXCPTN 2 | |
15 | #define BAD_IRQ 3 | |
16 | #define BAD_UNDEFINSTR 4 | |
17 | ||
1da177e4 | 18 | @ |
925c8a1a RK |
19 | @ Most of the stack format comes from struct pt_regs, but with |
20 | @ the addition of 8 bytes for storing syscall args 5 and 6. | |
2dede2d8 | 21 | @ This _must_ remain a multiple of 8 for EABI. |
1da177e4 | 22 | @ |
1da177e4 LT |
23 | #define S_OFF 8 |
24 | ||
925c8a1a RK |
25 | /* |
26 | * The SWI code relies on the fact that R0 is at the bottom of the stack | |
27 | * (due to slow/fast restore user regs). | |
28 | */ | |
29 | #if S_R0 != 0 | |
30 | #error "Please fix" | |
31 | #endif | |
32 | ||
bce495d8 RK |
33 | .macro zero_fp |
34 | #ifdef CONFIG_FRAME_POINTER | |
35 | mov fp, #0 | |
36 | #endif | |
37 | .endm | |
38 | ||
49f680ea | 39 | .macro alignment_trap, rtemp |
1da177e4 | 40 | #ifdef CONFIG_ALIGNMENT_TRAP |
49f680ea RK |
41 | ldr \rtemp, .LCcralign |
42 | ldr \rtemp, [\rtemp] | |
1da177e4 LT |
43 | mcr p15, 0, \rtemp, c1, c0 |
44 | #endif | |
45 | .endm | |
46 | ||
b86040a5 CM |
47 | @ |
48 | @ Store/load the USER SP and LR registers by switching to the SYS | |
49 | @ mode. Useful in Thumb-2 mode where "stm/ldm rd, {sp, lr}^" is not | |
50 | @ available. Should only be called from SVC mode | |
51 | @ | |
52 | .macro store_user_sp_lr, rd, rtemp, offset = 0 | |
53 | mrs \rtemp, cpsr | |
54 | eor \rtemp, \rtemp, #(SVC_MODE ^ SYSTEM_MODE) | |
55 | msr cpsr_c, \rtemp @ switch to the SYS mode | |
56 | ||
57 | str sp, [\rd, #\offset] @ save sp_usr | |
58 | str lr, [\rd, #\offset + 4] @ save lr_usr | |
59 | ||
60 | eor \rtemp, \rtemp, #(SVC_MODE ^ SYSTEM_MODE) | |
61 | msr cpsr_c, \rtemp @ switch back to the SVC mode | |
62 | .endm | |
63 | ||
64 | .macro load_user_sp_lr, rd, rtemp, offset = 0 | |
65 | mrs \rtemp, cpsr | |
66 | eor \rtemp, \rtemp, #(SVC_MODE ^ SYSTEM_MODE) | |
67 | msr cpsr_c, \rtemp @ switch to the SYS mode | |
68 | ||
69 | ldr sp, [\rd, #\offset] @ load sp_usr | |
70 | ldr lr, [\rd, #\offset + 4] @ load lr_usr | |
71 | ||
72 | eor \rtemp, \rtemp, #(SVC_MODE ^ SYSTEM_MODE) | |
73 | msr cpsr_c, \rtemp @ switch back to the SVC mode | |
74 | .endm | |
75 | ||
76 | #ifndef CONFIG_THUMB2_KERNEL | |
77 | .macro svc_exit, rpsr | |
78 | msr spsr_cxsf, \rpsr | |
7db44c75 | 79 | #if defined(CONFIG_CPU_V6) |
200b812d CM |
80 | ldr r0, [sp] |
81 | strex r1, r2, [sp] @ clear the exclusive monitor | |
82 | ldmib sp, {r1 - pc}^ @ load r1 - pc, cpsr | |
7db44c75 RK |
83 | #elif defined(CONFIG_CPU_32v6K) |
84 | clrex @ clear the exclusive monitor | |
85 | ldmia sp, {r0 - pc}^ @ load r0 - pc, cpsr | |
9e6ec39b NP |
86 | #else |
87 | ldmia sp, {r0 - pc}^ @ load r0 - pc, cpsr | |
200b812d | 88 | #endif |
b86040a5 CM |
89 | .endm |
90 | ||
91 | .macro restore_user_regs, fast = 0, offset = 0 | |
92 | ldr r1, [sp, #\offset + S_PSR] @ get calling cpsr | |
93 | ldr lr, [sp, #\offset + S_PC]! @ get pc | |
94 | msr spsr_cxsf, r1 @ save in spsr_svc | |
7db44c75 | 95 | #if defined(CONFIG_CPU_V6) |
200b812d | 96 | strex r1, r2, [sp] @ clear the exclusive monitor |
7db44c75 RK |
97 | #elif defined(CONFIG_CPU_32v6K) |
98 | clrex @ clear the exclusive monitor | |
200b812d | 99 | #endif |
b86040a5 CM |
100 | .if \fast |
101 | ldmdb sp, {r1 - lr}^ @ get calling r1 - lr | |
102 | .else | |
103 | ldmdb sp, {r0 - lr}^ @ get calling r0 - lr | |
104 | .endif | |
8e4971f2 AG |
105 | mov r0, r0 @ ARMv5T and earlier require a nop |
106 | @ after ldm {}^ | |
b86040a5 CM |
107 | add sp, sp, #S_FRAME_SIZE - S_PC |
108 | movs pc, lr @ return & move spsr_svc into cpsr | |
109 | .endm | |
110 | ||
111 | .macro get_thread_info, rd | |
112 | mov \rd, sp, lsr #13 | |
113 | mov \rd, \rd, lsl #13 | |
114 | .endm | |
a771fe6e CM |
115 | |
116 | @ | |
117 | @ 32-bit wide "mov pc, reg" | |
118 | @ | |
119 | .macro movw_pc, reg | |
120 | mov pc, \reg | |
121 | .endm | |
b86040a5 CM |
122 | #else /* CONFIG_THUMB2_KERNEL */ |
123 | .macro svc_exit, rpsr | |
59481062 JM |
124 | ldr lr, [sp, #S_SP] @ top of the stack |
125 | ldrd r0, r1, [sp, #S_LR] @ calling lr and pc | |
200b812d | 126 | clrex @ clear the exclusive monitor |
59481062 | 127 | stmdb lr!, {r0, r1, \rpsr} @ calling lr and rfe context |
b86040a5 | 128 | ldmia sp, {r0 - r12} |
59481062 JM |
129 | mov sp, lr |
130 | ldr lr, [sp], #4 | |
b86040a5 CM |
131 | rfeia sp! |
132 | .endm | |
133 | ||
134 | .macro restore_user_regs, fast = 0, offset = 0 | |
200b812d | 135 | clrex @ clear the exclusive monitor |
b86040a5 CM |
136 | mov r2, sp |
137 | load_user_sp_lr r2, r3, \offset + S_SP @ calling sp, lr | |
138 | ldr r1, [sp, #\offset + S_PSR] @ get calling cpsr | |
139 | ldr lr, [sp, #\offset + S_PC] @ get pc | |
140 | add sp, sp, #\offset + S_SP | |
141 | msr spsr_cxsf, r1 @ save in spsr_svc | |
142 | .if \fast | |
143 | ldmdb sp, {r1 - r12} @ get calling r1 - r12 | |
144 | .else | |
145 | ldmdb sp, {r0 - r12} @ get calling r0 - r12 | |
146 | .endif | |
147 | add sp, sp, #S_FRAME_SIZE - S_SP | |
148 | movs pc, lr @ return & move spsr_svc into cpsr | |
149 | .endm | |
150 | ||
151 | .macro get_thread_info, rd | |
152 | mov \rd, sp | |
153 | lsr \rd, \rd, #13 | |
154 | mov \rd, \rd, lsl #13 | |
155 | .endm | |
a771fe6e CM |
156 | |
157 | @ | |
158 | @ 32-bit wide "mov pc, reg" | |
159 | @ | |
160 | .macro movw_pc, reg | |
161 | mov pc, \reg | |
162 | nop | |
163 | .endm | |
b86040a5 | 164 | #endif /* !CONFIG_THUMB2_KERNEL */ |
1da177e4 LT |
165 | |
166 | /* | |
167 | * These are the registers used in the syscall handler, and allow us to | |
168 | * have in theory up to 7 arguments to a function - r0 to r6. | |
169 | * | |
170 | * r7 is reserved for the system call number for thumb mode. | |
171 | * | |
172 | * Note that tbl == why is intentional. | |
173 | * | |
174 | * We must set at least "tsk" and "why" when calling ret_with_reschedule. | |
175 | */ | |
176 | scno .req r7 @ syscall number | |
177 | tbl .req r8 @ syscall table pointer | |
178 | why .req r8 @ Linux syscall (!= 0) | |
179 | tsk .req r9 @ current thread_info |