*
* Copyright (C) 1996,1997,1998 Russell King.
* ARM700 fix by Matthew Godbolt (linux-user@willothewisp.demon.co.uk)
+ * nommu support by Hyok S. Choi (hyok.choi@samsung.com)
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
*/
#include <linux/config.h>
+#include <asm/memory.h>
#include <asm/glue.h>
#include <asm/vfpmacros.h>
-#include <asm/hardware.h> /* should be moved into entry-macro.S */
-#include <asm/arch/irqs.h> /* should be moved into entry-macro.S */
#include <asm/arch/entry-macro.S>
#include "entry-header.S"
+/*
+ * Interrupt handling. Preserves r7, r8, r9
+ */
+ .macro irq_handler
+1: get_irqnr_and_base r0, r6, r5, lr
+ movne r1, sp
+ @
+ @ routine called with r0 = irq number, r1 = struct pt_regs *
+ @
+ adrne lr, 1b
+ bne asm_do_IRQ
+
+#ifdef CONFIG_SMP
+ /*
+ * XXX
+ *
+ * this macro assumes that irqstat (r6) and base (r5) are
+ * preserved from get_irqnr_and_base above
+ */
+ test_for_ipi r0, r6, r5, lr
+ movne r0, sp
+ adrne lr, 1b
+ bne do_IPI
+
+#ifdef CONFIG_LOCAL_TIMERS
+ test_for_ltirq r0, r6, r5, lr
+ movne r0, sp
+ adrne lr, 1b
+ bne do_local_timer
+#endif
+#endif
+
+ .endm
+
/*
* Invalid mode handlers
*/
- .macro inv_entry, sym, reason
- sub sp, sp, #S_FRAME_SIZE @ Allocate frame size in one go
- stmia sp, {r0 - lr} @ Save XXX r0 - lr
- ldr r4, .LC\sym
+ .macro inv_entry, reason
+ sub sp, sp, #S_FRAME_SIZE
+ stmib sp, {r1 - lr}
mov r1, #\reason
.endm
__pabt_invalid:
- inv_entry abt, BAD_PREFETCH
- b 1f
+ inv_entry BAD_PREFETCH
+ b common_invalid
__dabt_invalid:
- inv_entry abt, BAD_DATA
- b 1f
+ inv_entry BAD_DATA
+ b common_invalid
__irq_invalid:
- inv_entry irq, BAD_IRQ
- b 1f
+ inv_entry BAD_IRQ
+ b common_invalid
__und_invalid:
- inv_entry und, BAD_UNDEFINSTR
+ inv_entry BAD_UNDEFINSTR
+
+ @
+ @ XXX fall through to common_invalid
+ @
+
+@
+@ common_invalid - generic code for failed exception (re-entrant version of handlers)
+@
+common_invalid:
+ zero_fp
+
+ ldmia r0, {r4 - r6}
+ add r0, sp, #S_PC @ here for interlock avoidance
+ mov r7, #-1 @ "" "" "" ""
+ str r4, [sp] @ save preserved r0
+ stmia r0, {r5 - r7} @ lr_<exception>,
+ @ cpsr_<exception>, "old_r0"
-1: zero_fp
- ldmia r4, {r5 - r7} @ Get XXX pc, cpsr, old_r0
- add r4, sp, #S_PC
- stmia r4, {r5 - r7} @ Save XXX pc, cpsr, old_r0
mov r0, sp
- and r2, r6, #31 @ int mode
+ and r2, r6, #0x1f
b bad_mode
/*
* SVC mode handlers
*/
- .macro svc_entry, sym
+
+#if defined(CONFIG_AEABI) && (__LINUX_ARM_ARCH__ >= 5)
+#define SPFIX(code...) code
+#else
+#define SPFIX(code...)
+#endif
+
+ .macro svc_entry
sub sp, sp, #S_FRAME_SIZE
- stmia sp, {r0 - r12} @ save r0 - r12
- ldr r2, .LC\sym
- add r0, sp, #S_FRAME_SIZE
- ldmia r2, {r2 - r4} @ get pc, cpsr
- add r5, sp, #S_SP
+ SPFIX( tst sp, #4 )
+ SPFIX( bicne sp, sp, #4 )
+ stmib sp, {r1 - r12}
+
+ ldmia r0, {r1 - r3}
+ add r5, sp, #S_SP @ here for interlock avoidance
+ mov r4, #-1 @ "" "" "" ""
+ add r0, sp, #S_FRAME_SIZE @ "" "" "" ""
+ SPFIX( addne r0, r0, #4 )
+ str r1, [sp] @ save the "real" r0 copied
+ @ from the exception stack
+
mov r1, lr
@
.align 5
__dabt_svc:
- svc_entry abt
+ svc_entry
@
@ get ready to re-enable interrupts if appropriate
.align 5
__irq_svc:
- svc_entry irq
+ svc_entry
+
#ifdef CONFIG_PREEMPT
- get_thread_info r8
- ldr r9, [r8, #TI_PREEMPT] @ get preempt count
- add r7, r9, #1 @ increment it
- str r7, [r8, #TI_PREEMPT]
+ get_thread_info tsk
+ ldr r8, [tsk, #TI_PREEMPT] @ get preempt count
+ add r7, r8, #1 @ increment it
+ str r7, [tsk, #TI_PREEMPT]
#endif
-1: get_irqnr_and_base r0, r6, r5, lr
- movne r1, sp
- @
- @ routine called with r0 = irq number, r1 = struct pt_regs *
- @
- adrne lr, 1b
- bne asm_do_IRQ
+
+ irq_handler
#ifdef CONFIG_PREEMPT
- ldr r0, [r8, #TI_FLAGS] @ get flags
+ ldr r0, [tsk, #TI_FLAGS] @ get flags
tst r0, #_TIF_NEED_RESCHED
blne svc_preempt
preempt_return:
- ldr r0, [r8, #TI_PREEMPT] @ read preempt value
+ ldr r0, [tsk, #TI_PREEMPT] @ read preempt value
+ str r8, [tsk, #TI_PREEMPT] @ restore preempt count
teq r0, r7
- str r9, [r8, #TI_PREEMPT] @ restore preempt count
strne r0, [r0, -r0] @ bug()
#endif
ldr r0, [sp, #S_PSR] @ irqs are already disabled
#ifdef CONFIG_PREEMPT
svc_preempt:
- teq r9, #0 @ was preempt count = 0
+ teq r8, #0 @ was preempt count = 0
ldreq r6, .LCirq_stat
movne pc, lr @ no
ldr r0, [r6, #4] @ local_irq_count
adds r0, r0, r1
movne pc, lr
mov r7, #0 @ preempt_schedule_irq
- str r7, [r8, #TI_PREEMPT] @ expects preempt_count == 0
+ str r7, [tsk, #TI_PREEMPT] @ expects preempt_count == 0
1: bl preempt_schedule_irq @ irq en/disable is done inside
- ldr r0, [r8, #TI_FLAGS] @ get new tasks TI_FLAGS
+ ldr r0, [tsk, #TI_FLAGS] @ get new tasks TI_FLAGS
tst r0, #_TIF_NEED_RESCHED
beq preempt_return @ go again
b 1b
.align 5
__und_svc:
- svc_entry und
+ svc_entry
@
@ call emulation code, which returns using r9 if it has emulated
.align 5
__pabt_svc:
- svc_entry abt
+ svc_entry
@
@ re-enable interrupts if appropriate
ldmia sp, {r0 - pc}^ @ load r0 - pc, cpsr
.align 5
-.LCirq:
- .word __temp_irq
-.LCund:
- .word __temp_und
-.LCabt:
- .word __temp_abt
+.LCcralign:
+ .word cr_alignment
#ifdef MULTI_ABORT
.LCprocfns:
.word processor
/*
* User mode handlers
+ *
+ * EABI note: sp_svc is always 64-bit aligned here, so should S_FRAME_SIZE
*/
- .macro usr_entry, sym
- sub sp, sp, #S_FRAME_SIZE @ Allocate frame size in one go
- stmia sp, {r0 - r12} @ save r0 - r12
- ldr r7, .LC\sym
- add r5, sp, #S_PC
- ldmia r7, {r2 - r4} @ Get USR pc, cpsr
+
+#if defined(CONFIG_AEABI) && (__LINUX_ARM_ARCH__ >= 5) && (S_FRAME_SIZE & 7)
+#error "sizeof(struct pt_regs) must be a multiple of 8"
+#endif
+
+ .macro usr_entry
+ sub sp, sp, #S_FRAME_SIZE
+ stmib sp, {r1 - r12}
+
+ ldmia r0, {r1 - r3}
+ add r0, sp, #S_PC @ here for interlock avoidance
+ mov r4, #-1 @ "" "" "" ""
+
+ str r1, [sp] @ save the "real" r0 copied
+ @ from the exception stack
#if __LINUX_ARM_ARCH__ < 6 && !defined(CONFIG_NEEDS_SYSCALL_FOR_CMPXCHG)
+#ifndef CONFIG_MMU
+#warning "NPTL on non MMU needs fixing"
+#else
@ make sure our user space atomic helper is aborted
- cmp r2, #VIRT_OFFSET
+ cmp r2, #TASK_SIZE
bichs r3, r3, #PSR_Z_BIT
+#endif
#endif
@
@
@ Also, separately save sp_usr and lr_usr
@
- stmia r5, {r2 - r4}
- stmdb r5, {sp, lr}^
+ stmia r0, {r2 - r4}
+ stmdb r0, {sp, lr}^
@
@ Enable the alignment trap while in kernel mode
@
- alignment_trap r7, r0, __temp_\sym
+ alignment_trap r0
@
@ Clear FP to mark the first stack frame
.align 5
__dabt_usr:
- usr_entry abt
+ usr_entry
@
@ Call the processor-specific abort handler:
.align 5
__irq_usr:
- usr_entry irq
+ usr_entry
+ get_thread_info tsk
#ifdef CONFIG_PREEMPT
- get_thread_info r8
- ldr r9, [r8, #TI_PREEMPT] @ get preempt count
- add r7, r9, #1 @ increment it
- str r7, [r8, #TI_PREEMPT]
+ ldr r8, [tsk, #TI_PREEMPT] @ get preempt count
+ add r7, r8, #1 @ increment it
+ str r7, [tsk, #TI_PREEMPT]
#endif
-1: get_irqnr_and_base r0, r6, r5, lr
- movne r1, sp
- adrne lr, 1b
- @
- @ routine called with r0 = irq number, r1 = struct pt_regs *
- @
- bne asm_do_IRQ
+
+ irq_handler
#ifdef CONFIG_PREEMPT
- ldr r0, [r8, #TI_PREEMPT]
+ ldr r0, [tsk, #TI_PREEMPT]
+ str r8, [tsk, #TI_PREEMPT]
teq r0, r7
- str r9, [r8, #TI_PREEMPT]
strne r0, [r0, -r0]
- mov tsk, r8
-#else
- get_thread_info tsk
#endif
+
mov why, #0
b ret_to_user
.align 5
__und_usr:
- usr_entry und
+ usr_entry
tst r3, #PSR_T_BIT @ Thumb mode?
bne fpundefinstr @ ignore FP
movcss r7, r5, lsr #(TIF_USING_IWMMXT + 1)
bcs iwmmxt_task_enable
#endif
- enable_irq
add pc, pc, r8, lsr #6
mov r0, r0
mov pc, lr @ CP#15 (Control)
do_fpe:
+ enable_irq
ldr r4, .LCfp
add r10, r10, #TI_FPSTATE @ r10 = workspace
ldr pc, [r4] @ Call FP module USR entry point
.align 5
__pabt_usr:
- usr_entry abt
+ usr_entry
enable_irq @ Enable interrupts
mov r0, r2 @ address (pc)
add ip, r1, #TI_CPU_SAVE
ldr r3, [r2, #TI_TP_VALUE]
stmia ip!, {r4 - sl, fp, sp, lr} @ Store most regs on stack
+#ifndef CONFIG_MMU
+ add r2, r2, #TI_CPU_DOMAIN
+#else
ldr r6, [r2, #TI_CPU_DOMAIN]!
+#endif
+#if __LINUX_ARM_ARCH__ >= 6
+#ifdef CONFIG_CPU_32v6K
+ clrex
+#else
+ strex r5, r4, [ip] @ Clear exclusive monitor
+#endif
+#endif
#if defined(CONFIG_CPU_XSCALE) && !defined(CONFIG_IWMMXT)
mra r4, r5, acc0
stmia ip, {r4, r5}
mov r4, #0xffff0fff
str r3, [r4, #-15] @ TLS val at 0xffff0ff0
#endif
+#ifdef CONFIG_MMU
mcr p15, 0, r6, c3, c0, 0 @ Set domain register
+#endif
#ifdef CONFIG_VFP
@ Always disable VFP so we can lazily save/restore the old
@ state. This occurs in the context of the previous thread.
.globl __kuser_helper_start
__kuser_helper_start:
+/*
+ * Reference prototype:
+ *
+ * void __kernel_memory_barrier(void)
+ *
+ * Input:
+ *
+ * lr = return address
+ *
+ * Output:
+ *
+ * none
+ *
+ * Clobbered:
+ *
+ * the Z flag might be lost
+ *
+ * Definition and user space usage example:
+ *
+ * typedef void (__kernel_dmb_t)(void);
+ * #define __kernel_dmb (*(__kernel_dmb_t *)0xffff0fa0)
+ *
+ * Apply any needed memory barrier to preserve consistency with data modified
+ * manually and __kuser_cmpxchg usage.
+ *
+ * This could be used as follows:
+ *
+ * #define __kernel_dmb() \
+ * asm volatile ( "mov r0, #0xffff0fff; mov lr, pc; sub pc, r0, #95" \
+ * : : : "r0", "lr","cc" )
+ */
+
+__kuser_memory_barrier: @ 0xffff0fa0
+
+#if __LINUX_ARM_ARCH__ >= 6 && defined(CONFIG_SMP)
+ mcr p15, 0, r0, c7, c10, 5 @ dmb
+#endif
+ mov pc, lr
+
+ .align 5
+
/*
* Reference prototype:
*
* The C flag is also set if *ptr was changed to allow for assembly
* optimization in the calling code.
*
+ * Notes:
+ *
+ * - This routine already includes memory barriers as needed.
+ *
+ * - A failure might be transient, i.e. it is possible, although unlikely,
+ * that "failure" be returned even if *ptr == oldval.
+ *
* For example, a user space atomic_add implementation could look like this:
*
* #define atomic_add(ptr, val) \
* The kernel itself must perform the operation.
* A special ghost syscall is used for that (see traps.c).
*/
+ stmfd sp!, {r7, lr}
+ mov r7, #0xff00 @ 0xfff0 into r7 for EABI
+ orr r7, r7, #0xf0
swi #0x9ffff0
- mov pc, lr
+ ldmfd sp!, {r7, pc}
#elif __LINUX_ARM_ARCH__ < 6
* exception happening just after the str instruction which would
* clear the Z flag although the exchange was done.
*/
+#ifdef CONFIG_MMU
teq ip, ip @ set Z flag
ldr ip, [r2] @ load current val
add r3, r2, #1 @ prepare store ptr
teqeq ip, r0 @ compare with oldval if still allowed
streq r1, [r3, #-1]! @ store newval if still allowed
subs r0, r2, r3 @ if r2 == r3 the str occured
+#else
+#warning "NPTL on non MMU needs fixing"
+ mov r0, #-1
+ adds r0, r0, #0
+#endif
mov pc, lr
#else
+#ifdef CONFIG_SMP
+ mcr p15, 0, r0, c7, c10, 5 @ dmb
+#endif
ldrex r3, [r2]
subs r3, r3, r0
strexeq r3, r1, [r2]
rsbs r0, r3, #0
+#ifdef CONFIG_SMP
+ mcr p15, 0, r0, c7, c10, 5 @ dmb
+#endif
mov pc, lr
#endif
*
* Common stub entry macro:
* Enter in IRQ mode, spsr = SVC/USR CPSR, lr = SVC/USR PC
+ *
+ * SP points to a minimal amount of processor-private memory, the address
+ * of which is copied into r0 for the mode specific abort handler.
*/
- .macro vector_stub, name, sym, correction=0
+ .macro vector_stub, name, mode, correction=0
.align 5
vector_\name:
- ldr r13, .LCs\sym
.if \correction
sub lr, lr, #\correction
.endif
- str lr, [r13] @ save lr_IRQ
+
+ @
+ @ Save r0, lr_<exception> (parent PC) and spsr_<exception>
+ @ (parent CPSR)
+ @
+ stmia sp, {r0, lr} @ save r0, lr
mrs lr, spsr
- str lr, [r13, #4] @ save spsr_IRQ
+ str lr, [sp, #8] @ save spsr
+
@
- @ now branch to the relevant MODE handling routine
+ @ Prepare for SVC32 mode. IRQs remain disabled.
@
- mrs r13, cpsr
- bic r13, r13, #MODE_MASK
- orr r13, r13, #SVC_MODE
- msr spsr_cxsf, r13 @ switch to SVC_32 mode
+ mrs r0, cpsr
+ eor r0, r0, #(\mode ^ SVC_MODE)
+ msr spsr_cxsf, r0
- and lr, lr, #15
+ @
+ @ the branch table must immediately follow this code
+ @
+ and lr, lr, #0x0f
+ mov r0, sp
ldr lr, [pc, lr, lsl #2]
- movs pc, lr @ Changes mode and branches
+ movs pc, lr @ branch to handler in SVC mode
.endm
.globl __stubs_start
/*
* Interrupt dispatcher
*/
- vector_stub irq, irq, 4
+ vector_stub irq, IRQ_MODE, 4
.long __irq_usr @ 0 (USR_26 / USR_32)
.long __irq_invalid @ 1 (FIQ_26 / FIQ_32)
* Data abort dispatcher
* Enter in ABT mode, spsr = USR CPSR, lr = USR PC
*/
- vector_stub dabt, abt, 8
+ vector_stub dabt, ABT_MODE, 8
.long __dabt_usr @ 0 (USR_26 / USR_32)
.long __dabt_invalid @ 1 (FIQ_26 / FIQ_32)
* Prefetch abort dispatcher
* Enter in ABT mode, spsr = USR CPSR, lr = USR PC
*/
- vector_stub pabt, abt, 4
+ vector_stub pabt, ABT_MODE, 4
.long __pabt_usr @ 0 (USR_26 / USR_32)
.long __pabt_invalid @ 1 (FIQ_26 / FIQ_32)
* Undef instr entry dispatcher
* Enter in UND mode, spsr = SVC/USR CPSR, lr = SVC/USR PC
*/
- vector_stub und, und
+ vector_stub und, UND_MODE
.long __und_usr @ 0 (USR_26 / USR_32)
.long __und_invalid @ 1 (FIQ_26 / FIQ_32)
.LCvswi:
.word vector_swi
-.LCsirq:
- .word __temp_irq
-.LCsund:
- .word __temp_und
-.LCsabt:
- .word __temp_abt
-
.globl __stubs_end
__stubs_end:
.data
-/*
- * Do not reorder these, and do not insert extra data between...
- */
-
-__temp_irq:
- .word 0 @ saved lr_irq
- .word 0 @ saved spsr_irq
- .word -1 @ old_r0
-__temp_und:
- .word 0 @ Saved lr_und
- .word 0 @ Saved spsr_und
- .word -1 @ old_r0
-__temp_abt:
- .word 0 @ Saved lr_abt
- .word 0 @ Saved spsr_abt
- .word -1 @ old_r0
-
.globl cr_alignment
.globl cr_no_alignment
cr_alignment:
git://git.onelab.eu / linux-2.6.git / blobdiff