summaryrefslogtreecommitdiffstats
path: root/arch/arm/kernel/entry-armv.S
diff options
context:
space:
mode:
authorCatalin Marinas <catalin.marinas@arm.com>2009-07-24 12:32:54 +0100
committerCatalin Marinas <catalin.marinas@arm.com>2009-07-24 12:32:54 +0100
commitb86040a59feb255a8193173caa4d5199464433d5 (patch)
tree89c07450eabc2abb88bb4d6e32d61fd3855f000e /arch/arm/kernel/entry-armv.S
parent0becb088501886f37ade38762c8eaaf4263572cc (diff)
downloadop-kernel-dev-b86040a59feb255a8193173caa4d5199464433d5.zip
op-kernel-dev-b86040a59feb255a8193173caa4d5199464433d5.tar.gz
Thumb-2: Implementation of the unified start-up and exceptions code
This patch implements the ARM/Thumb-2 unified kernel start-up and exception handling code. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Diffstat (limited to 'arch/arm/kernel/entry-armv.S')
-rw-r--r--arch/arm/kernel/entry-armv.S165
1 files changed, 98 insertions, 67 deletions
diff --git a/arch/arm/kernel/entry-armv.S b/arch/arm/kernel/entry-armv.S
index 0befd1c..468425f 100644
--- a/arch/arm/kernel/entry-armv.S
+++ b/arch/arm/kernel/entry-armv.S
@@ -34,7 +34,7 @@
@
@ routine called with r0 = irq number, r1 = struct pt_regs *
@
- adrne lr, 1b
+ adrne lr, BSYM(1b)
bne asm_do_IRQ
#ifdef CONFIG_SMP
@@ -46,13 +46,13 @@
*/
test_for_ipi r0, r6, r5, lr
movne r0, sp
- adrne lr, 1b
+ adrne lr, BSYM(1b)
bne do_IPI
#ifdef CONFIG_LOCAL_TIMERS
test_for_ltirq r0, r6, r5, lr
movne r0, sp
- adrne lr, 1b
+ adrne lr, BSYM(1b)
bne do_local_timer
#endif
#endif
@@ -70,7 +70,10 @@
*/
.macro inv_entry, reason
sub sp, sp, #S_FRAME_SIZE
- stmib sp, {r1 - lr}
+ ARM( stmib sp, {r1 - lr} )
+ THUMB( stmia sp, {r0 - r12} )
+ THUMB( str sp, [sp, #S_SP] )
+ THUMB( str lr, [sp, #S_LR] )
mov r1, #\reason
.endm
@@ -126,17 +129,24 @@ ENDPROC(__und_invalid)
.macro svc_entry, stack_hole=0
UNWIND(.fnstart )
UNWIND(.save {r0 - pc} )
- sub sp, sp, #(S_FRAME_SIZE + \stack_hole)
+ sub sp, sp, #(S_FRAME_SIZE + \stack_hole - 4)
+#ifdef CONFIG_THUMB2_KERNEL
+ SPFIX( str r0, [sp] ) @ temporarily saved
+ SPFIX( mov r0, sp )
+ SPFIX( tst r0, #4 ) @ test original stack alignment
+ SPFIX( ldr r0, [sp] ) @ restored
+#else
SPFIX( tst sp, #4 )
- SPFIX( bicne sp, sp, #4 )
- stmib sp, {r1 - r12}
+#endif
+ SPFIX( subeq sp, sp, #4 )
+ stmia sp, {r1 - r12}
ldmia r0, {r1 - r3}
- add r5, sp, #S_SP @ here for interlock avoidance
+ add r5, sp, #S_SP - 4 @ here for interlock avoidance
mov r4, #-1 @ "" "" "" ""
- add r0, sp, #(S_FRAME_SIZE + \stack_hole)
- SPFIX( addne r0, r0, #4 )
- str r1, [sp] @ save the "real" r0 copied
+ add r0, sp, #(S_FRAME_SIZE + \stack_hole - 4)
+ SPFIX( addeq r0, r0, #4 )
+ str r1, [sp, #-4]! @ save the "real" r0 copied
@ from the exception stack
mov r1, lr
@@ -196,9 +206,8 @@ __dabt_svc:
@
@ restore SPSR and restart the instruction
@
- ldr r0, [sp, #S_PSR]
- msr spsr_cxsf, r0
- ldmia sp, {r0 - pc}^ @ load r0 - pc, cpsr
+ ldr r2, [sp, #S_PSR]
+ svc_exit r2 @ return from exception
UNWIND(.fnend )
ENDPROC(__dabt_svc)
@@ -225,13 +234,12 @@ __irq_svc:
tst r0, #_TIF_NEED_RESCHED
blne svc_preempt
#endif
- ldr r0, [sp, #S_PSR] @ irqs are already disabled
- msr spsr_cxsf, r0
+ ldr r4, [sp, #S_PSR] @ irqs are already disabled
#ifdef CONFIG_TRACE_IRQFLAGS
- tst r0, #PSR_I_BIT
+ tst r4, #PSR_I_BIT
bleq trace_hardirqs_on
#endif
- ldmia sp, {r0 - pc}^ @ load r0 - pc, cpsr
+ svc_exit r4 @ return from exception
UNWIND(.fnend )
ENDPROC(__irq_svc)
@@ -266,7 +274,7 @@ __und_svc:
@ r0 - instruction
@
ldr r0, [r2, #-4]
- adr r9, 1f
+ adr r9, BSYM(1f)
bl call_fpe
mov r0, sp @ struct pt_regs *regs
@@ -280,9 +288,8 @@ __und_svc:
@
@ restore SPSR and restart the instruction
@
- ldr lr, [sp, #S_PSR] @ Get SVC cpsr
- msr spsr_cxsf, lr
- ldmia sp, {r0 - pc}^ @ Restore SVC registers
+ ldr r2, [sp, #S_PSR] @ Get SVC cpsr
+ svc_exit r2 @ return from exception
UNWIND(.fnend )
ENDPROC(__und_svc)
@@ -323,9 +330,8 @@ __pabt_svc:
@
@ restore SPSR and restart the instruction
@
- ldr r0, [sp, #S_PSR]
- msr spsr_cxsf, r0
- ldmia sp, {r0 - pc}^ @ load r0 - pc, cpsr
+ ldr r2, [sp, #S_PSR]
+ svc_exit r2 @ return from exception
UNWIND(.fnend )
ENDPROC(__pabt_svc)
@@ -353,7 +359,8 @@ ENDPROC(__pabt_svc)
UNWIND(.fnstart )
UNWIND(.cantunwind ) @ don't unwind the user space
sub sp, sp, #S_FRAME_SIZE
- stmib sp, {r1 - r12}
+ ARM( stmib sp, {r1 - r12} )
+ THUMB( stmia sp, {r0 - r12} )
ldmia r0, {r1 - r3}
add r0, sp, #S_PC @ here for interlock avoidance
@@ -372,7 +379,8 @@ ENDPROC(__pabt_svc)
@ Also, separately save sp_usr and lr_usr
@
stmia r0, {r2 - r4}
- stmdb r0, {sp, lr}^
+ ARM( stmdb r0, {sp, lr}^ )
+ THUMB( store_user_sp_lr r0, r1, S_SP - S_PC )
@
@ Enable the alignment trap while in kernel mode
@@ -427,7 +435,7 @@ __dabt_usr:
@
enable_irq
mov r2, sp
- adr lr, ret_from_exception
+ adr lr, BSYM(ret_from_exception)
b do_DataAbort
UNWIND(.fnend )
ENDPROC(__dabt_usr)
@@ -452,7 +460,9 @@ __irq_usr:
ldr r0, [tsk, #TI_PREEMPT]
str r8, [tsk, #TI_PREEMPT]
teq r0, r7
- strne r0, [r0, -r0]
+ ARM( strne r0, [r0, -r0] )
+ THUMB( movne r0, #0 )
+ THUMB( strne r0, [r0] )
#endif
#ifdef CONFIG_TRACE_IRQFLAGS
bl trace_hardirqs_on
@@ -476,9 +486,10 @@ __und_usr:
@
@ r0 - instruction
@
- adr r9, ret_from_exception
- adr lr, __und_usr_unknown
+ adr r9, BSYM(ret_from_exception)
+ adr lr, BSYM(__und_usr_unknown)
tst r3, #PSR_T_BIT @ Thumb mode?
+ itet eq @ explicit IT needed for the 1f label
subeq r4, r2, #4 @ ARM instr at LR - 4
subne r4, r2, #2 @ Thumb instr at LR - 2
1: ldreqt r0, [r4]
@@ -488,7 +499,10 @@ __und_usr:
beq call_fpe
@ Thumb instruction
#if __LINUX_ARM_ARCH__ >= 7
-2: ldrht r5, [r4], #2
+2:
+ ARM( ldrht r5, [r4], #2 )
+ THUMB( ldrht r5, [r4] )
+ THUMB( add r4, r4, #2 )
and r0, r5, #0xf800 @ mask bits 111x x... .... ....
cmp r0, #0xe800 @ 32bit instruction if xx != 0
blo __und_usr_unknown
@@ -577,9 +591,11 @@ call_fpe:
moveq pc, lr
get_thread_info r10 @ get current thread
and r8, r0, #0x00000f00 @ mask out CP number
+ THUMB( lsr r8, r8, #8 )
mov r7, #1
add r6, r10, #TI_USED_CP
- strb r7, [r6, r8, lsr #8] @ set appropriate used_cp[]
+ ARM( strb r7, [r6, r8, lsr #8] ) @ set appropriate used_cp[]
+ THUMB( strb r7, [r6, r8] ) @ set appropriate used_cp[]
#ifdef CONFIG_IWMMXT
@ Test if we need to give access to iWMMXt coprocessors
ldr r5, [r10, #TI_FLAGS]
@@ -587,36 +603,38 @@ call_fpe:
movcss r7, r5, lsr #(TIF_USING_IWMMXT + 1)
bcs iwmmxt_task_enable
#endif
- add pc, pc, r8, lsr #6
- mov r0, r0
-
- mov pc, lr @ CP#0
- b do_fpe @ CP#1 (FPE)
- b do_fpe @ CP#2 (FPE)
- mov pc, lr @ CP#3
+ ARM( add pc, pc, r8, lsr #6 )
+ THUMB( lsl r8, r8, #2 )
+ THUMB( add pc, r8 )
+ nop
+
+ W(mov) pc, lr @ CP#0
+ W(b) do_fpe @ CP#1 (FPE)
+ W(b) do_fpe @ CP#2 (FPE)
+ W(mov) pc, lr @ CP#3
#ifdef CONFIG_CRUNCH
b crunch_task_enable @ CP#4 (MaverickCrunch)
b crunch_task_enable @ CP#5 (MaverickCrunch)
b crunch_task_enable @ CP#6 (MaverickCrunch)
#else
- mov pc, lr @ CP#4
- mov pc, lr @ CP#5
- mov pc, lr @ CP#6
+ W(mov) pc, lr @ CP#4
+ W(mov) pc, lr @ CP#5
+ W(mov) pc, lr @ CP#6
#endif
- mov pc, lr @ CP#7
- mov pc, lr @ CP#8
- mov pc, lr @ CP#9
+ W(mov) pc, lr @ CP#7
+ W(mov) pc, lr @ CP#8
+ W(mov) pc, lr @ CP#9
#ifdef CONFIG_VFP
- b do_vfp @ CP#10 (VFP)
- b do_vfp @ CP#11 (VFP)
+ W(b) do_vfp @ CP#10 (VFP)
+ W(b) do_vfp @ CP#11 (VFP)
#else
- mov pc, lr @ CP#10 (VFP)
- mov pc, lr @ CP#11 (VFP)
+ W(mov) pc, lr @ CP#10 (VFP)
+ W(mov) pc, lr @ CP#11 (VFP)
#endif
- mov pc, lr @ CP#12
- mov pc, lr @ CP#13
- mov pc, lr @ CP#14 (Debug)
- mov pc, lr @ CP#15 (Control)
+ W(mov) pc, lr @ CP#12
+ W(mov) pc, lr @ CP#13
+ W(mov) pc, lr @ CP#14 (Debug)
+ W(mov) pc, lr @ CP#15 (Control)
#ifdef CONFIG_NEON
.align 6
@@ -667,7 +685,7 @@ no_fp: mov pc, lr
__und_usr_unknown:
enable_irq
mov r0, sp
- adr lr, ret_from_exception
+ adr lr, BSYM(ret_from_exception)
b do_undefinstr
ENDPROC(__und_usr_unknown)
@@ -711,7 +729,10 @@ ENTRY(__switch_to)
UNWIND(.cantunwind )
add ip, r1, #TI_CPU_SAVE
ldr r3, [r2, #TI_TP_VALUE]
- stmia ip!, {r4 - sl, fp, sp, lr} @ Store most regs on stack
+ ARM( stmia ip!, {r4 - sl, fp, sp, lr} ) @ Store most regs on stack
+ THUMB( stmia ip!, {r4 - sl, fp} ) @ Store most regs on stack
+ THUMB( str sp, [ip], #4 )
+ THUMB( str lr, [ip], #4 )
#ifdef CONFIG_MMU
ldr r6, [r2, #TI_CPU_DOMAIN]
#endif
@@ -736,8 +757,12 @@ ENTRY(__switch_to)
ldr r0, =thread_notify_head
mov r1, #THREAD_NOTIFY_SWITCH
bl atomic_notifier_call_chain
+ THUMB( mov ip, r4 )
mov r0, r5
- ldmia r4, {r4 - sl, fp, sp, pc} @ Load all regs saved previously
+ ARM( ldmia r4, {r4 - sl, fp, sp, pc} ) @ Load all regs saved previously
+ THUMB( ldmia ip!, {r4 - sl, fp} ) @ Load all regs saved previously
+ THUMB( ldr sp, [ip], #4 )
+ THUMB( ldr pc, [ip] )
UNWIND(.fnend )
ENDPROC(__switch_to)
@@ -772,6 +797,7 @@ ENDPROC(__switch_to)
* if your compiled code is not going to use the new instructions for other
* purpose.
*/
+ THUMB( .arm )
.macro usr_ret, reg
#ifdef CONFIG_ARM_THUMB
@@ -1020,6 +1046,7 @@ __kuser_helper_version: @ 0xffff0ffc
.globl __kuser_helper_end
__kuser_helper_end:
+ THUMB( .thumb )
/*
* Vector stubs.
@@ -1054,15 +1081,17 @@ vector_\name:
@ Prepare for SVC32 mode. IRQs remain disabled.
@
mrs r0, cpsr
- eor r0, r0, #(\mode ^ SVC_MODE)
+ eor r0, r0, #(\mode ^ SVC_MODE | PSR_ISETSTATE)
msr spsr_cxsf, r0
@
@ the branch table must immediately follow this code
@
and lr, lr, #0x0f
+ THUMB( adr r0, 1f )
+ THUMB( ldr lr, [r0, lr, lsl #2] )
mov r0, sp
- ldr lr, [pc, lr, lsl #2]
+ ARM( ldr lr, [pc, lr, lsl #2] )
movs pc, lr @ branch to handler in SVC mode
ENDPROC(vector_\name)
@@ -1206,14 +1235,16 @@ __stubs_end:
.globl __vectors_start
__vectors_start:
- swi SYS_ERROR0
- b vector_und + stubs_offset
- ldr pc, .LCvswi + stubs_offset
- b vector_pabt + stubs_offset
- b vector_dabt + stubs_offset
- b vector_addrexcptn + stubs_offset
- b vector_irq + stubs_offset
- b vector_fiq + stubs_offset
+ ARM( swi SYS_ERROR0 )
+ THUMB( svc #0 )
+ THUMB( nop )
+ W(b) vector_und + stubs_offset
+ W(ldr) pc, .LCvswi + stubs_offset
+ W(b) vector_pabt + stubs_offset
+ W(b) vector_dabt + stubs_offset
+ W(b) vector_addrexcptn + stubs_offset
+ W(b) vector_irq + stubs_offset
+ W(b) vector_fiq + stubs_offset
.globl __vectors_end
__vectors_end:
OpenPOWER on IntegriCloud