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authorMark Brown <broonie@opensource.wolfsonmicro.com>2009-10-06 16:01:27 +0100
committerMark Brown <broonie@opensource.wolfsonmicro.com>2009-10-06 16:01:27 +0100
commit907bc6c7fc7071b00083fc11e510e47dd93df45d (patch)
tree0697a608561522c00da9e1814974a2eb051bb96d /arch/arm/kernel/entry-header.S
parentd2b247a8be57647d1745535acd58169fbcbe431a (diff)
parent2a0f5cb32772e9a9560209e241a80bfbbc31dbc3 (diff)
Merge branch 'for-2.6.32' into for-2.6.33
Diffstat (limited to 'arch/arm/kernel/entry-header.S')
-rw-r--r--arch/arm/kernel/entry-header.S108
1 files changed, 103 insertions, 5 deletions
diff --git a/arch/arm/kernel/entry-header.S b/arch/arm/kernel/entry-header.S
index 87ab4e15799..ac34c0d9384 100644
--- a/arch/arm/kernel/entry-header.S
+++ b/arch/arm/kernel/entry-header.S
@@ -36,11 +36,6 @@
#endif
.endm
- .macro get_thread_info, rd
- mov \rd, sp, lsr #13
- mov \rd, \rd, lsl #13
- .endm
-
.macro alignment_trap, rtemp
#ifdef CONFIG_ALIGNMENT_TRAP
ldr \rtemp, .LCcralign
@@ -49,6 +44,109 @@
#endif
.endm
+ @
+ @ Store/load the USER SP and LR registers by switching to the SYS
+ @ mode. Useful in Thumb-2 mode where "stm/ldm rd, {sp, lr}^" is not
+ @ available. Should only be called from SVC mode
+ @
+ .macro store_user_sp_lr, rd, rtemp, offset = 0
+ mrs \rtemp, cpsr
+ eor \rtemp, \rtemp, #(SVC_MODE ^ SYSTEM_MODE)
+ msr cpsr_c, \rtemp @ switch to the SYS mode
+
+ str sp, [\rd, #\offset] @ save sp_usr
+ str lr, [\rd, #\offset + 4] @ save lr_usr
+
+ eor \rtemp, \rtemp, #(SVC_MODE ^ SYSTEM_MODE)
+ msr cpsr_c, \rtemp @ switch back to the SVC mode
+ .endm
+
+ .macro load_user_sp_lr, rd, rtemp, offset = 0
+ mrs \rtemp, cpsr
+ eor \rtemp, \rtemp, #(SVC_MODE ^ SYSTEM_MODE)
+ msr cpsr_c, \rtemp @ switch to the SYS mode
+
+ ldr sp, [\rd, #\offset] @ load sp_usr
+ ldr lr, [\rd, #\offset + 4] @ load lr_usr
+
+ eor \rtemp, \rtemp, #(SVC_MODE ^ SYSTEM_MODE)
+ msr cpsr_c, \rtemp @ switch back to the SVC mode
+ .endm
+
+#ifndef CONFIG_THUMB2_KERNEL
+ .macro svc_exit, rpsr
+ msr spsr_cxsf, \rpsr
+#if defined(CONFIG_CPU_32v6K)
+ clrex @ clear the exclusive monitor
+ ldmia sp, {r0 - pc}^ @ load r0 - pc, cpsr
+#elif defined (CONFIG_CPU_V6)
+ ldr r0, [sp]
+ strex r1, r2, [sp] @ clear the exclusive monitor
+ ldmib sp, {r1 - pc}^ @ load r1 - pc, cpsr
+#else
+ ldmia sp, {r0 - pc}^ @ load r0 - pc, cpsr
+#endif
+ .endm
+
+ .macro restore_user_regs, fast = 0, offset = 0
+ ldr r1, [sp, #\offset + S_PSR] @ get calling cpsr
+ ldr lr, [sp, #\offset + S_PC]! @ get pc
+ msr spsr_cxsf, r1 @ save in spsr_svc
+#if defined(CONFIG_CPU_32v6K)
+ clrex @ clear the exclusive monitor
+#elif defined (CONFIG_CPU_V6)
+ strex r1, r2, [sp] @ clear the exclusive monitor
+#endif
+ .if \fast
+ ldmdb sp, {r1 - lr}^ @ get calling r1 - lr
+ .else
+ ldmdb sp, {r0 - lr}^ @ get calling r0 - lr
+ .endif
+ add sp, sp, #S_FRAME_SIZE - S_PC
+ movs pc, lr @ return & move spsr_svc into cpsr
+ .endm
+
+ .macro get_thread_info, rd
+ mov \rd, sp, lsr #13
+ mov \rd, \rd, lsl #13
+ .endm
+#else /* CONFIG_THUMB2_KERNEL */
+ .macro svc_exit, rpsr
+ clrex @ clear the exclusive monitor
+ ldr r0, [sp, #S_SP] @ top of the stack
+ ldr r1, [sp, #S_PC] @ return address
+ tst r0, #4 @ orig stack 8-byte aligned?
+ stmdb r0, {r1, \rpsr} @ rfe context
+ ldmia sp, {r0 - r12}
+ ldr lr, [sp, #S_LR]
+ addeq sp, sp, #S_FRAME_SIZE - 8 @ aligned
+ addne sp, sp, #S_FRAME_SIZE - 4 @ not aligned
+ rfeia sp!
+ .endm
+
+ .macro restore_user_regs, fast = 0, offset = 0
+ clrex @ clear the exclusive monitor
+ mov r2, sp
+ load_user_sp_lr r2, r3, \offset + S_SP @ calling sp, lr
+ ldr r1, [sp, #\offset + S_PSR] @ get calling cpsr
+ ldr lr, [sp, #\offset + S_PC] @ get pc
+ add sp, sp, #\offset + S_SP
+ msr spsr_cxsf, r1 @ save in spsr_svc
+ .if \fast
+ ldmdb sp, {r1 - r12} @ get calling r1 - r12
+ .else
+ ldmdb sp, {r0 - r12} @ get calling r0 - r12
+ .endif
+ add sp, sp, #S_FRAME_SIZE - S_SP
+ movs pc, lr @ return & move spsr_svc into cpsr
+ .endm
+
+ .macro get_thread_info, rd
+ mov \rd, sp
+ lsr \rd, \rd, #13
+ mov \rd, \rd, lsl #13
+ .endm
+#endif /* !CONFIG_THUMB2_KERNEL */
/*
* These are the registers used in the syscall handler, and allow us to