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>
diff --git a/arch/arm/kernel/head.S b/arch/arm/kernel/head.S
index 21e17dc..38ccbe1 100644
--- a/arch/arm/kernel/head.S
+++ b/arch/arm/kernel/head.S
@@ -76,7 +76,7 @@
*/
.section ".text.head", "ax"
ENTRY(stext)
- msr cpsr_c, #PSR_F_BIT | PSR_I_BIT | SVC_MODE @ ensure svc mode
+ setmode PSR_F_BIT | PSR_I_BIT | SVC_MODE, r9 @ ensure svc mode
@ and irqs disabled
mrc p15, 0, r9, c0, c0 @ get processor id
bl __lookup_processor_type @ r5=procinfo r9=cpuid
@@ -97,8 +97,10 @@
*/
ldr r13, __switch_data @ address to jump to after
@ mmu has been enabled
- adr lr, __enable_mmu @ return (PIC) address
- add pc, r10, #PROCINFO_INITFUNC
+ adr lr, BSYM(__enable_mmu) @ return (PIC) address
+ ARM( add pc, r10, #PROCINFO_INITFUNC )
+ THUMB( add r12, r10, #PROCINFO_INITFUNC )
+ THUMB( mov pc, r12 )
ENDPROC(stext)
#if defined(CONFIG_SMP)
@@ -110,7 +112,7 @@
* the processor type - there is no need to check the machine type
* as it has already been validated by the primary processor.
*/
- msr cpsr_c, #PSR_F_BIT | PSR_I_BIT | SVC_MODE
+ setmode PSR_F_BIT | PSR_I_BIT | SVC_MODE, r9
mrc p15, 0, r9, c0, c0 @ get processor id
bl __lookup_processor_type
movs r10, r5 @ invalid processor?
@@ -121,12 +123,15 @@
* Use the page tables supplied from __cpu_up.
*/
adr r4, __secondary_data
- ldmia r4, {r5, r7, r13} @ address to jump to after
+ ldmia r4, {r5, r7, r12} @ address to jump to after
sub r4, r4, r5 @ mmu has been enabled
ldr r4, [r7, r4] @ get secondary_data.pgdir
- adr lr, __enable_mmu @ return address
- add pc, r10, #PROCINFO_INITFUNC @ initialise processor
- @ (return control reg)
+ adr lr, BSYM(__enable_mmu) @ return address
+ mov r13, r12 @ __secondary_switched address
+ ARM( add pc, r10, #PROCINFO_INITFUNC ) @ initialise processor
+ @ (return control reg)
+ THUMB( add r12, r10, #PROCINFO_INITFUNC )
+ THUMB( mov pc, r12 )
ENDPROC(secondary_startup)
/*
@@ -193,8 +198,8 @@
mcr p15, 0, r0, c1, c0, 0 @ write control reg
mrc p15, 0, r3, c0, c0, 0 @ read id reg
mov r3, r3
- mov r3, r3
- mov pc, r13
+ mov r3, r13
+ mov pc, r3
ENDPROC(__turn_mmu_on)
@@ -235,7 +240,8 @@
* will be removed by paging_init(). We use our current program
* counter to determine corresponding section base address.
*/
- mov r6, pc, lsr #20 @ start of kernel section
+ mov r6, pc
+ mov r6, r6, lsr #20 @ start of kernel section
orr r3, r7, r6, lsl #20 @ flags + kernel base
str r3, [r4, r6, lsl #2] @ identity mapping