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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/arm/kernel/entry-header.S
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'arch/arm/kernel/entry-header.S')
-rw-r--r--arch/arm/kernel/entry-header.S182
1 files changed, 182 insertions, 0 deletions
diff --git a/arch/arm/kernel/entry-header.S b/arch/arm/kernel/entry-header.S
new file mode 100644
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1#include <linux/config.h> /* for CONFIG_ARCH_xxxx */
2#include <linux/linkage.h>
3
4#include <asm/assembler.h>
5#include <asm/constants.h>
6#include <asm/errno.h>
7#include <asm/hardware.h>
8#include <asm/arch/irqs.h>
9#include <asm/arch/entry-macro.S>
10
11#ifndef MODE_SVC
12#define MODE_SVC 0x13
13#endif
14
15 .macro zero_fp
16#ifdef CONFIG_FRAME_POINTER
17 mov fp, #0
18#endif
19 .endm
20
21 .text
22
23@ Bad Abort numbers
24@ -----------------
25@
26#define BAD_PREFETCH 0
27#define BAD_DATA 1
28#define BAD_ADDREXCPTN 2
29#define BAD_IRQ 3
30#define BAD_UNDEFINSTR 4
31
32#define PT_TRACESYS 0x00000002
33
34@ OS version number used in SWIs
35@ RISC OS is 0
36@ RISC iX is 8
37@
38#define OS_NUMBER 9
39#define ARMSWI_OFFSET 0x000f0000
40
41@
42@ Stack format (ensured by USER_* and SVC_*)
43@
44#define S_FRAME_SIZE 72
45#define S_OLD_R0 68
46#define S_PSR 64
47
48#define S_PC 60
49#define S_LR 56
50#define S_SP 52
51#define S_IP 48
52#define S_FP 44
53#define S_R10 40
54#define S_R9 36
55#define S_R8 32
56#define S_R7 28
57#define S_R6 24
58#define S_R5 20
59#define S_R4 16
60#define S_R3 12
61#define S_R2 8
62#define S_R1 4
63#define S_R0 0
64#define S_OFF 8
65
66 .macro set_cpsr_c, reg, mode
67 msr cpsr_c, \mode
68 .endm
69
70#if __LINUX_ARM_ARCH__ >= 6
71 .macro disable_irq, temp
72 cpsid i
73 .endm
74
75 .macro enable_irq, temp
76 cpsie i
77 .endm
78#else
79 .macro disable_irq, temp
80 set_cpsr_c \temp, #PSR_I_BIT | MODE_SVC
81 .endm
82
83 .macro enable_irq, temp
84 set_cpsr_c \temp, #MODE_SVC
85 .endm
86#endif
87
88 .macro save_user_regs
89 sub sp, sp, #S_FRAME_SIZE
90 stmia sp, {r0 - r12} @ Calling r0 - r12
91 add r8, sp, #S_PC
92 stmdb r8, {sp, lr}^ @ Calling sp, lr
93 mrs r8, spsr @ called from non-FIQ mode, so ok.
94 str lr, [sp, #S_PC] @ Save calling PC
95 str r8, [sp, #S_PSR] @ Save CPSR
96 str r0, [sp, #S_OLD_R0] @ Save OLD_R0
97 .endm
98
99 .macro restore_user_regs
100 ldr r1, [sp, #S_PSR] @ Get calling cpsr
101 disable_irq ip @ disable IRQs
102 ldr lr, [sp, #S_PC]! @ Get PC
103 msr spsr_cxsf, r1 @ save in spsr_svc
104 ldmdb sp, {r0 - lr}^ @ Get calling r0 - lr
105 mov r0, r0
106 add sp, sp, #S_FRAME_SIZE - S_PC
107 movs pc, lr @ return & move spsr_svc into cpsr
108 .endm
109
110/*
111 * Must be called with IRQs already disabled.
112 */
113 .macro fast_restore_user_regs
114 ldr r1, [sp, #S_OFF + S_PSR] @ get calling cpsr
115 ldr lr, [sp, #S_OFF + S_PC]! @ get pc
116 msr spsr_cxsf, r1 @ save in spsr_svc
117 ldmdb sp, {r1 - lr}^ @ get calling r1 - lr
118 mov r0, r0
119 add sp, sp, #S_FRAME_SIZE - S_PC
120 movs pc, lr @ return & move spsr_svc into cpsr
121 .endm
122
123/*
124 * Must be called with IRQs already disabled.
125 */
126 .macro slow_restore_user_regs
127 ldr r1, [sp, #S_PSR] @ get calling cpsr
128 ldr lr, [sp, #S_PC]! @ get pc
129 msr spsr_cxsf, r1 @ save in spsr_svc
130 ldmdb sp, {r0 - lr}^ @ get calling r1 - lr
131 mov r0, r0
132 add sp, sp, #S_FRAME_SIZE - S_PC
133 movs pc, lr @ return & move spsr_svc into cpsr
134 .endm
135
136 .macro mask_pc, rd, rm
137 .endm
138
139 .macro get_thread_info, rd
140 mov \rd, sp, lsr #13
141 mov \rd, \rd, lsl #13
142 .endm
143
144 .macro alignment_trap, rbase, rtemp, sym
145#ifdef CONFIG_ALIGNMENT_TRAP
146#define OFF_CR_ALIGNMENT(x) cr_alignment - x
147
148 ldr \rtemp, [\rbase, #OFF_CR_ALIGNMENT(\sym)]
149 mcr p15, 0, \rtemp, c1, c0
150#endif
151 .endm
152
153
154/*
155 * These are the registers used in the syscall handler, and allow us to
156 * have in theory up to 7 arguments to a function - r0 to r6.
157 *
158 * r7 is reserved for the system call number for thumb mode.
159 *
160 * Note that tbl == why is intentional.
161 *
162 * We must set at least "tsk" and "why" when calling ret_with_reschedule.
163 */
164scno .req r7 @ syscall number
165tbl .req r8 @ syscall table pointer
166why .req r8 @ Linux syscall (!= 0)
167tsk .req r9 @ current thread_info
168
169/*
170 * Get the system call number.
171 */
172 .macro get_scno
173#ifdef CONFIG_ARM_THUMB
174 tst r8, #PSR_T_BIT @ this is SPSR from save_user_regs
175 addne scno, r7, #OS_NUMBER << 20 @ put OS number in
176 ldreq scno, [lr, #-4]
177
178#else
179 mask_pc lr, lr
180 ldr scno, [lr, #-4] @ get SWI instruction
181#endif
182 .endm