/* $Id: entry.S,v 1.28 2005/06/20 05:06:30 starvik Exp $
*
* linux/arch/cris/entry.S
*
* Copyright (C) 2000, 2001, 2002 Axis Communications AB
*
* Authors: Bjorn Wesen (bjornw@axis.com)
*
* $Log: entry.S,v $
* Revision 1.28 2005/06/20 05:06:30 starvik
* Remove unnecessary diff to kernel.org tree
*
* Revision 1.27 2005/03/04 08:16:16 starvik
* Merge of Linux 2.6.11.
*
* Revision 1.26 2005/01/11 13:49:47 starvik
* Added NMI handler.
*
* Revision 1.25 2004/12/27 11:18:32 starvik
* Merge of Linux 2.6.10 (not functional yet).
*
* Revision 1.24 2004/12/22 10:41:23 starvik
* Updates to make v10 compile with the latest SMP aware generic code (even
* though v10 will never have SMP).
*
* Revision 1.23 2004/10/19 13:07:37 starvik
* Merge of Linux 2.6.9
*
* Revision 1.22 2004/06/21 10:29:55 starvik
* Merge of Linux 2.6.7
*
* Revision 1.21 2004/06/09 05:30:27 starvik
* Clean up multiple interrupt handling.
* Prevent interrupts from interrupting each other.
* Handle all active interrupts.
*
* Revision 1.20 2004/06/08 08:55:32 starvik
* Removed unused code
*
* Revision 1.19 2004/06/04 11:56:15 starvik
* Implemented page table lookup for refills in assembler for improved performance.
*
* Revision 1.18 2004/05/11 12:28:25 starvik
* Merge of Linux 2.6.6
*
* Revision 1.17 2003/09/11 07:29:49 starvik
* Merge of Linux 2.6.0-test5
*
* Revision 1.16 2003/07/04 08:27:41 starvik
* Merge of Linux 2.5.74
*
* Revision 1.15 2003/04/09 07:32:55 starvik
* resume should return task_struct, not thread_info
*
* Revision 1.14 2003/04/09 05:20:44 starvik
* Merge of Linux 2.5.67
*
* Revision 1.13 2002/12/11 15:42:02 starvik
* Extracted v10 (ETRAX 100LX) specific stuff from arch/cris/kernel/*.c
*
* Revision 1.12 2002/12/10 09:00:10 starvik
* Merge of Linux 2.5.51
*
* Revision 1.11 2002/12/05 07:53:10 starvik
* Corrected constants used with btstq
*
* Revision 1.10 2002/11/27 08:45:10 starvik
* pid is in task_struct, not thread_info
*
* Revision 1.9 2002/11/26 09:52:05 starvik
* Added preemptive kernel scheduling (if CONFIG_PREEMPT)
*
* Revision 1.8 2002/11/20 11:56:11 starvik
* Merge of Linux 2.5.48
*
* Revision 1.7 2002/11/18 13:02:42 starvik
* Added fourth parameter to do_notify_resume
* Minor cleanup
*
* Revision 1.6 2002/11/11 10:37:50 starvik
* Use new asm-offset defines
* Modified for new location of current->work etc
* Removed SYMBOL_NAME from syscalls
* Added some new syscalls
*
* Revision 1.5 2002/11/05 06:45:11 starvik
* Merge of Linux 2.5.45
*
* Revision 1.4 2002/02/05 15:41:31 bjornw
* Rewritten to conform better to current 2.5 code (similar to arch/i386)
*
* Revision 1.3 2002/01/21 15:22:20 bjornw
* NICE_DOGGY fix from 2.4 arch/cris
*
* Revision 1.37 2001/12/07 17:03:55 bjornw
* Call a c-hook called watchdog_bite_hook instead of show_registers directly
*
* Revision 1.36 2001/11/22 13:36:36 bjornw
* * In ret_from_intr, check regs->dccr for usermode reentrance instead of
* DCCR explicitly (because the latter might not reflect current reality)
* * In mmu_bus_fault, set $r9 _after_ calling the C-code instead of before
* since $r9 is call-clobbered and is potentially needed afterwards
*
* Revision 1.35 2001/10/30 17:10:15 bjornw
* Add some syscalls
*
* Revision 1.34 2001/10/01 14:45:03 bjornw
* Removed underscores and added register prefixes
*
* Revision 1.33 2001/08/21 13:48:01 jonashg
* Added fix by HP to avoid oops when doing a hard_reset_now.
*
* Revision 1.32 2001/08/14 04:32:02 hp
* In _resume, add comment why R9 is saved; don't sound like it's call-saved.
*
* Revision 1.31 2001/07/25 16:07:42 bjornw
* softirq_active/mask -> softirq_pending only
*
* Revision 1.30 2001/07/05 01:03:32 hp
* - include asm/errno.h to get ENOSYS.
* - Use ENOSYS, not local constant LENOSYS; tweak comments.
* - Explain why .include, not #include is used.
* - Make oops-register-dump if watchdog bits and it's not expected.
* - Don't jsr, use jump _hard_reset_now, and skip spurious nop.
* - Use correct section attribute for section .rodata.
* - Adjust sys_ni_syscall fill number.
*
* Revision 1.29 2001/06/25 14:07:00 hp
* Fix review comment.
* * head.S: Use IO_STATE, IO_FIELD and IO_MASK constructs instead of
* magic numbers. Add comment that -traditional must not be used.
* * entry.S (SYMBOL_NAME): Change redefinition to use ## concatenation.
* Correct and update comment.
* * Makefile (.S.o): Don't use -traditional. Add comment why the
* toplevel rule can't be used (now that there's a reason).
*
* Revision 1.28 2001/06/21 02:00:40 hp
* * entry.S: Include asm/unistd.h.
* (_sys_call_table): Use section .rodata, not .data.
* (_kernel_thread): Move from...
* * process.c: ... here.
* * entryoffsets.c (VAL): Break out from...
* (OF): Use VAL.
* (LCLONE_VM): New asmified value from CLONE_VM.
*
* Revision 1.27 2001/05/29 11:25:27 markusl
* In case of "spurious_interrupt", do hard_reset instead of hanging system in a loop...
*
* Revision 1.26 2001/05/15 15:46:03 bjornw
* Include config.h now that we use some CONFIG_ options
*
* Revision 1.25 2001/05/15 05:38:47 hp
* Tweaked code in _ret_from_sys_call
*
* Revision 1.24 2001/05/15 05:27:49 hp
* Save r9 in r1 over function call rather than on stack.
*
* Revision 1.23 2001/05/15 05:10:00 hp
* Generate entry.S structure offsets from C
*
* Revision 1.22 2001/04/17 13:58:39 orjanf
* * Renamed CONFIG_KGDB to CONFIG_ETRAX_KGDB.
*
* Revision 1.21 2001/04/17 11:33:29 orjanf
* Updated according to review:
* * Included asm/sv_addr_ag.h to get macro for internal register.
* * Corrected comment regarding system call argument passing.
* * Removed comment about instruction being in a delay slot.
* * Added comment about SYMBOL_NAME macro.
*
* Revision 1.20 2001/04/12 08:51:07 hp
* - Add entry for sys_fcntl64. In fact copy last piece from i386 including ...
* - .rept to fill table to safe state with sys_ni_syscall.
*
* Revision 1.19 2001/04/04 09:43:32 orjanf
* * Moved do_sigtrap from traps.c to entry.S.
* * LTASK_PID need not be global anymore.
*
* Revision 1.18 2001/03/26 09:25:02 markusl
* Updated after review, should now handle USB interrupts correctly.
*
* Revision 1.17 2001/03/21 16:12:55 bjornw
* * Always make room for the cpu status record in the frame, in order to
* use the same framelength and layout for both mmu busfaults and normal
* irqs. No need to check for the explicit CRIS_FRAME_FIXUP type anymore.
* * Fixed bug with using addq for popping the stack in the epilogue - it
* destroyed the flag register. Use instructions that don't affect the
* flag register instead.
* * Removed write to R_PORT_PA_DATA during spurious_interrupt
*
* Revision 1.16 2001/03/20 19:43:02 bjornw
* * Get rid of esp0 setting
* * Give a 7th argument to a systemcall - the stackframe
*
* Revision 1.15 2001/03/05 13:14:30 bjornw
* Spelling fix
*
* Revision 1.14 2001/02/23 08:36:36 perf
* New ABI; syscallnr=r9, arg5=mof, arg6=srp.
* Corrected tracesys call check.
*
* Revision 1.13 2001/02/15 08:40:55 perf
* H-P by way of perf;
* - (_system_call): Don't read system call function address into r1.
* - (RBFExit): There is no such thing as a null pop. Adjust sp by addq.
* - (_system_call): Don't use r10 and don't save and restore it.
* - (THREAD_ESP0): New constant.
* - (_system_call): Inline set_esp0.
*
* Revision 1.12 2001/01/31 17:56:25 orjanf
* Added definition of LTASK_PID and made it global.
*
* Revision 1.11 2001/01/10 21:13:29 bjornw
* SYMBOL_NAME is defined incorrectly for the compiler options we currently use
*
* Revision 1.10 2000/12/18 23:47:56 bjornw
* * Added syscall trace support (ptrace), completely untested of course
* * Removed redundant check for NULL entries in syscall_table
*
* Revision 1.9 2000/11/21 16:40:51 bjornw
* * New frame type used when an SBFS frame needs to be popped without
* actually restarting the instruction
* * Enable interrupts in signal_return (they did so in x86, I hope it's a good
* idea)
*
* Revision 1.8 2000/11/17 16:53:35 bjornw
* Added detection of frame-type in Rexit, so that mmu_bus_fault can
* use ret_from_intr in the return-path to check for signals (like SEGV)
* and other foul things that might have occurred during the fault.
*
* Revision 1.7 2000/10/06 15:04:28 bjornw
* Include mof in register savings
*
* Revision 1.6 2000/09/12 16:02:44 bjornw
* Linux-2.4.0-test7 derived updates
*
* Revision 1.5 2000/08/17 15:35:15 bjornw
* 2.4.0-test6 changed local_irq_count and friends API
*
* Revision 1.4 2000/08/02 13:59:30 bjornw
* Removed olduname and uname from the syscall list
*
* Revision 1.3 2000/07/31 13:32:58 bjornw
* * Export ret_from_intr
* * _resume updated (prev/last tjohejsan)
* * timer_interrupt obsolete
* * SIGSEGV detection in mmu_bus_fault temporarily disabled
*
*
*/
/*
* entry.S contains the system-call and fault low-level handling routines.
*
* NOTE: This code handles signal-recognition, which happens every time
* after a timer-interrupt and after each system call.
*
* Stack layout in 'ret_from_system_call':
* ptrace needs to have all regs on the stack.
* if the order here is changed, it needs to be
* updated in fork.c:copy_process, signal.c:do_signal,
* ptrace.c and ptrace.h
*
*/
#include <linux/linkage.h>
#include <linux/sys.h>
#include <asm/unistd.h>
#include <asm/arch/sv_addr_ag.h>
#include <asm/errno.h>
#include <asm/thread_info.h>
#include <asm/asm-offsets.h>
#include <asm/page.h>
#include <asm/pgtable.h>
;; functions exported from this file
.globl system_call
.globl ret_from_intr
.globl ret_from_fork
.globl resume
.globl multiple_interrupt
.globl hwbreakpoint
.globl IRQ1_interrupt
.globl spurious_interrupt
.globl hw_bp_trigs
.globl mmu_bus_fault
.globl do_sigtrap
.globl gdb_handle_breakpoint
.globl sys_call_table
;; below are various parts of system_call which are not in the fast-path
#ifdef CONFIG_PREEMPT
; Check if preemptive kernel scheduling should be done
_resume_kernel:
di
; Load current task struct
movs.w -8192, $r0 ; THREAD_SIZE = 8192
and.d $sp, $r0
move.d [$r0+TI_preempt_count], $r10 ; Preemption disabled?
bne _Rexit
nop
_need_resched:
move.d [$r0+TI_flags], $r10
btstq TIF_NEED_RESCHED, $r10 ; Check if need_resched is set
bpl _Rexit
nop
; Ok, lets's do some preemptive kernel scheduling
jsr preempt_schedule_irq
; Load new task struct
movs.w -8192, $r0 ; THREAD_SIZE = 8192
and.d $sp, $r0
; One more time (with new task)
ba _need_resched
nop
#else
#define _resume_kernel _Rexit
#endif
; Called at exit from fork. schedule_tail must be called to drop
; spinlock if CONFIG_PREEMPT
ret_from_fork:
jsr schedule_tail
ba ret_from_sys_call
nop
ret_from_intr:
;; check for resched if preemptive kernel or if we're going back to user-mode
;; this test matches the user_regs(regs) macro
;; we cannot simply test $dccr, because that does not necessarily
;; reflect what mode we'll return into.
move.d [$sp + PT_dccr], $r0; regs->dccr
btstq 8, $r0 ; U-flag
bpl _resume_kernel
; Note that di below is in delay slot
_resume_userspace:
di ; so need_resched and sigpending don't change
movs.w -8192, $r0 ; THREAD_SIZE == 8192
and.d $sp, $r0
move.d [$r0+TI_flags], $r10 ; current->work
and.d _TIF_WORK_MASK, $r10 ; is there any work to be done on return
bne _work_pending
nop
ba _Rexit
nop
;; The system_call is called by a BREAK instruction, which works like
;; an interrupt call but it stores the return PC in BRP instead of IRP.
;; Since we dont really want to have two epilogues (one for system calls
;; and one for interrupts) we push the contents of BRP instead of IRP in the
;; system call prologue, to make it look like an ordinary interrupt on the
;; stackframe.
;;
;; Since we can't have system calls inside interrupts, it should not matter
;; that we don't stack IRP.
;;
;; In r9 we have the wanted syscall number. Arguments come in r10,r11,r12,r13,mof,srp
;;
;; This function looks on the _surface_ like spaghetti programming, but it's
;; really designed so that the fast-path does not force cache-loading of non-used
;; instructions. Only the non-common cases cause the outlined code to run..
system_call:
;; stack-frame similar to the irq heads, which is reversed in ret_from_sys_call
move $brp,[$sp=$sp-16]; instruction pointer and room for a fake SBFS frame
push $srp
push $dccr
push $mof
subq 14*4, $sp ; make room for r0-r13
movem $r13, [$sp] ; push r0-r13
push $r10 ; push orig_r10
clear.d [$sp=$sp-4] ; frametype == 0, normal stackframe
movs.w -ENOSYS, $r0
move.d $r0, [$sp+PT_r10] ; put the default return value in r10 in the frame
;; check if this process is syscall-traced
movs.w -8192, $r0 ; THREAD_SIZE == 8192
and.d $sp, $r0
move.d [$r0+TI_flags], $r0
btstq TIF_SYSCALL_TRACE, $r0
bmi _syscall_trace_entry
nop
_syscall_traced:
;; check for sanity in the requested syscall number
cmpu.w NR_syscalls, $r9
bcc ret_from_sys_call
lslq 2, $r9 ; multiply by 4, in the delay slot
;; as a bonus 7th parameter, we give the location on the stack
;; of the register structure itself. some syscalls need this.
push $sp
;; the parameter carrying registers r10, r11, r12 and 13 are intact.
;; the fifth and sixth parameters (if any) was in mof and srp
;; respectively, and we need to put them on the stack.
push $srp
push $mof
jsr [$r9+sys_call_table] ; actually do the system call
addq 3*4, $sp ; pop the mof, srp and regs parameters
move.d $r10, [$sp+PT_r10] ; save the return value
moveq 1, $r9 ; "parameter" to ret_from_sys_call to show it was a sys call
;; fall through into ret_from_sys_call to return
ret_from_sys_call:
;; r9 is a parameter - if >=1 we came from a syscall, if 0, from an irq
;; get the current task-struct pointer (see top for defs)
movs.w -8192, $r0 ; THREAD_SIZE == 8192
and.d $sp, $r0
di ; make sure need_resched and sigpending don't change
move.d [$r0+TI_flags],$r1
and.d _TIF_ALLWORK_MASK, $r1
bne _syscall_exit_work
nop
_Rexit:
;; this epilogue MUST match the prologues in multiple_interrupt, irq.h and ptregs.h
pop $r10 ; frametype
bne _RBFexit ; was not CRIS_FRAME_NORMAL, handle otherwise
addq 4, $sp ; skip orig_r10, in delayslot
movem [$sp+], $r13 ; registers r0-r13
pop $mof ; multiply overflow register
pop $dccr ; condition codes
pop $srp ; subroutine return pointer
;; now we have a 4-word SBFS frame which we do not want to restore
;; using RBF since it was not stacked with SBFS. instead we would like to
;; just get the PC value to restart it with, and skip the rest of
;; the frame.
;; Also notice that it's important to use instructions here that
;; keep the interrupts disabled (since we've already popped DCCR)
move [$sp=$sp+16], $p8; pop the SBFS frame from the sp
jmpu [$sp-16] ; return through the irp field in the sbfs frame
_RBFexit:
movem [$sp+], $r13 ; registers r0-r13, in delay slot
pop $mof ; multiply overflow register
pop $dccr ; condition codes
pop $srp ; subroutine return pointer
rbf [$sp+] ; return by popping the CPU status
;; We get here after doing a syscall if extra work might need to be done
;; perform syscall exit tracing if needed
_syscall_exit_work:
;; $r0 contains current at this point and irq's are disabled
move.d [$r0+TI_flags], $r1
btstq TIF_SYSCALL_TRACE, $r1
bpl _work_pending
nop
ei
move.d $r9, $r1 ; preserve r9
jsr do_syscall_trace
move.d $r1, $r9
ba _resume_userspace
nop
_work_pending:
move.d [$r0+TI_flags], $r1
btstq TIF_NEED_RESCHED, $r1
bpl _work_notifysig ; was neither trace nor sched, must be signal/notify
nop
_work_resched:
move.d $r9, $r1 ; preserve r9
jsr schedule
move.d $r1, $r9
di
move.d [$r0+TI_flags], $r1
and.d _TIF_WORK_MASK, $r1; ignore the syscall trace counter
beq _Rexit
nop
btstq TIF_NEED_RESCHED, $r1
bmi _work_resched ; current->work.need_resched
nop
_work_notifysig:
;; deal with pending signals and notify-resume requests
move.d $r9, $r10 ; do_notify_resume syscall/irq param
moveq 0, $r11 ; oldset param - 0 in this case
move.d $sp, $r12 ; the regs param
move.d $r1, $r13 ; the thread_info_flags parameter
jsr do_notify_resume
ba _Rexit
nop
;; We get here as a sidetrack when we've entered a syscall with the
;; trace-bit set. We need to call do_syscall_trace and then continue
;; with the call.
_syscall_trace_entry:
;; PT_r10 in the frame contains -ENOSYS as required, at this point
jsr do_syscall_trace
;; now re-enter the syscall code to do the syscall itself
;; we need to restore $r9 here to contain the wanted syscall, and
;; the other parameter-bearing registers
move.d [$sp+PT_r9], $r9
move.d [$sp+PT_orig_r10], $r10 ; PT_r10 is already filled with -ENOSYS.
move.d [$sp+PT_r11], $r11
move.d [$sp+PT_r12], $r12
move.d [$sp+PT_r13], $r13
move [$sp+PT_mof], $mof
move [$sp+PT_srp], $srp
ba _syscall_traced
nop
;; resume performs the actual task-switching, by switching stack pointers
;; input arguments: r10 = prev, r11 = next, r12 = thread offset in task struct
;; returns old current in r10
;;
;; TODO: see the i386 version. The switch_to which calls resume in our version
;; could really be an inline asm of this.
resume:
push $srp ; we keep the old/new PC on the stack
add.d $r12, $r10 ; r10 = current tasks tss
move $dccr, [$r10+THREAD_dccr]; save irq enable state
di
move $usp, [$r10+ THREAD_usp] ; save user-mode stackpointer
;; See copy_thread for the reason why register R9 is saved.
subq 10*4, $sp
movem $r9, [$sp] ; save non-scratch registers and R9.
move.d $sp, [$r10+THREAD_ksp] ; save the kernel stack pointer for the old task
move.d $sp, $r10 ; return last running task in r10
and.d -8192, $r10 ; get thread_info from stackpointer
move.d [$r10+TI_task], $r10 ; get task
add.d $r12, $r11 ; find the new tasks tss
move.d [$r11+THREAD_ksp], $sp ; switch into the new stackframe by restoring kernel sp
movem [$sp+], $r9 ; restore non-scratch registers and R9.
move [$r11+THREAD_usp], $usp ; restore user-mode stackpointer
move [$r11+THREAD_dccr], $dccr ; restore irq enable status
jump [$sp+] ; restore PC
;; This is the MMU bus fault handler.
;; It needs to stack the CPU status and overall is different
;; from the other interrupt handlers.
mmu_bus_fault:
;; For refills we try to do a quick page table lookup. If it is
;; a real fault we let the mm subsystem handle it.
;; the first longword in the sbfs frame was the interrupted PC
;; which fits nicely with the "IRP" slot in pt_regs normally used to
;; contain the return address. used by Oops to print kernel errors.
sbfs [$sp=$sp-16] ; push the internal CPU status
push $dccr
di
subq 2*4, $sp
movem $r1, [$sp]
move.d [R_MMU_CAUSE], $r1
;; ETRAX 100LX TR89 bugfix: if the second half of an unaligned
;; write causes a MMU-fault, it will not be restarted correctly.
;; This could happen if a write crosses a page-boundary and the
;; second page is not yet COW'ed or even loaded. The workaround
;; is to clear the unaligned bit in the CPU status record, so
;; that the CPU will rerun both the first and second halves of
;; the instruction. This will not have any sideeffects unless
;; the first half goes to any device or memory that can't be
;; written twice, and which is mapped through the MMU.
;;
;; We only need to do this for writes.
btstq 8, $r1 ; Write access?
bpl 1f
nop
move.d [$sp+16], $r0 ; Clear unaligned bit in csrinstr
and.d ~(1<<5), $r0
move.d $r0, [$sp+16]
1: btstq 12, $r1 ; Refill?
bpl 2f
lsrq 24, $r1 ; Get PGD index (bit 24-31)
move.d [per_cpu__current_pgd], $r0 ; PGD for the current process
move.d [$r0+$r1.d], $r0 ; Get PMD
beq 2f
nop
and.w PAGE_MASK, $r0 ; Remove PMD flags
move.d [R_MMU_CAUSE], $r1
lsrq PAGE_SHIFT, $r1
and.d 0x7ff, $r1 ; Get PTE index into PGD (bit 13-23)
move.d [$r0+$r1.d], $r1 ; Get PTE
beq 2f
nop
;; Store in TLB
move.d $r1, [R_TLB_LO]
;; Return
movem [$sp+], $r1
pop $dccr
rbf [$sp+] ; return by popping the CPU status
2: ; PMD or PTE missing, let the mm subsystem fix it up.
movem [$sp+], $r1
pop $dccr
; Ok, not that easy, pass it on to the mm subsystem
; The MMU status record is now on the stack
push $srp ; make a stackframe similar to pt_regs
push $dccr
push $mof
di
subq 14*4, $sp
movem $r13, [$sp]
push $r10 ; dummy orig_r10
moveq 1, $r10
push $r10 ; frametype == 1, BUSFAULT frame type
move.d $sp, $r10 ; pt_regs argument to handle_mmu_bus_fault
jsr handle_mmu_bus_fault ; in arch/cris/arch-v10/mm/fault.c
;; now we need to return through the normal path, we cannot just
;; do the RBFexit since we might have killed off the running
;; process due to a SEGV, scheduled due to a page blocking or
;; whatever.
moveq 0, $r9 ; busfault is equivalent to an irq
ba ret_from_intr
nop
;; special handlers for breakpoint and NMI
hwbreakpoint:
push $dccr
di
push $r10
push $r11
move.d [hw_bp_trig_ptr],$r10
move $brp,$r11
move.d $r11,[$r10+]
move.d $r10,[hw_bp_trig_ptr]
1: pop $r11
pop $r10
pop $dccr
retb
nop
IRQ1_interrupt:
;; this prologue MUST match the one in irq.h and the struct in ptregs.h!!!
move $brp,[$sp=$sp-16]; instruction pointer and room for a fake SBFS frame
push $srp
push $dccr
push $mof
di
subq 14*4, $sp
movem $r13, [$sp]
push $r10 ; push orig_r10
clear.d [$sp=$sp-4] ; frametype == 0, normal frame
move.d [R_IRQ_MASK0_RD], $r1 ; External NMI or watchdog?
and.d 0x80000000, $r1
beq wdog
move.d $sp, $r10
jsr handle_nmi
setf m ; Enable NMI again
retb ; Return from NMI
nop
wdog:
#if defined(CONFIG_ETRAX_WATCHDOG) && !defined(CONFIG_SVINTO_SIM)
;; Check if we're waiting for reset to happen, as signalled by
;; hard_reset_now setting cause_of_death to a magic value. If so, just
;; get stuck until reset happens.
.comm cause_of_death, 4 ;; Don't declare this anywhere.
move.d [cause_of_death], $r10
cmp.d 0xbedead, $r10
_killed_by_death:
beq _killed_by_death
nop
;; We'll see this in ksymoops dumps.
Watchdog_bite:
#ifdef CONFIG_ETRAX_WATCHDOG_NICE_DOGGY
;; We just restart the watchdog here to be sure we dont get
;; hit while printing the watchdogmsg below
;; This restart is compatible with the rest of the C-code, so
;; the C-code can keep restarting the watchdog after this point.
;; The non-NICE_DOGGY code below though, disables the possibility
;; to restart since it changes the watchdog key, to avoid any
;; buggy loops etc. keeping the watchdog alive after this.
jsr reset_watchdog
#else
;; We need to extend the 3.3ms after the NMI at watchdog bite, so we have
;; time for an oops-dump over a 115k2 serial wire. Another 100ms should do.
;; Change the watchdog key to an arbitrary 3-bit value and restart the
;; watchdog.
#define WD_INIT 2
moveq IO_FIELD (R_WATCHDOG, key, WD_INIT), $r10
move.d R_WATCHDOG, $r11
move.d $r10, [$r11]
moveq IO_FIELD (R_WATCHDOG, key, \
IO_EXTRACT (R_WATCHDOG, key, \
IO_MASK (R_WATCHDOG, key)) \
^ WD_INIT) \
| IO_STATE (R_WATCHDOG, enable, start), $r10
move.d $r10, [$r11]
#endif
;; Note that we don't do "setf m" here (or after two necessary NOPs),
;; since *not* doing that saves us from re-entrancy checks. We don't want
;; to get here again due to possible subsequent NMIs; we want the watchdog
;; to reset us.
move.d _watchdogmsg,$r10
jsr printk
move.d $sp, $r10
jsr watchdog_bite_hook
;; This nop is here so we see the "Watchdog_bite" label in ksymoops dumps
;; rather than "spurious_interrupt".
nop
;; At this point we drop down into spurious_interrupt, which will do a
;; hard reset.
.section .rodata,"a"
_watchdogmsg:
.ascii "Oops: bitten by watchdog\n\0"
.previous
#endif /* CONFIG_ETRAX_WATCHDOG and not CONFIG_SVINTO_SIM */
spurious_interrupt:
di
jump hard_reset_now
;; this handles the case when multiple interrupts arrive at the same time
;; we jump to the first set interrupt bit in a priority fashion
;; the hardware will call the unserved interrupts after the handler finishes
multiple_interrupt:
;; this prologue MUST match the one in irq.h and the struct in ptregs.h!!!
move $irp,[$sp=$sp-16]; instruction pointer and room for a fake SBFS frame
push $srp
push $dccr
push $mof
di
subq 14*4, $sp
movem $r13, [$sp]
push $r10 ; push orig_r10
clear.d [$sp=$sp-4] ; frametype == 0, normal frame
moveq 2, $r2 ; first bit we care about is the timer0 irq
move.d [R_VECT_MASK_RD], $r0; read the irq bits that triggered the multiple irq
move.d $r0, [R_VECT_MASK_CLR] ; Block all active IRQs
1:
btst $r2, $r0 ; check for the irq given by bit r2
bpl 2f
move.d $r2, $r10 ; First argument to do_IRQ
move.d $sp, $r11 ; second argument to do_IRQ
jsr do_IRQ
2:
addq 1, $r2 ; next vector bit
cmp.b 32, $r2
bne 1b ; process all irq's up to and including number 31
moveq 0, $r9 ; make ret_from_intr realise we came from an ir
move.d $r0, [R_VECT_MASK_SET] ; Unblock all the IRQs
jump ret_from_intr
do_sigtrap:
;;
;; SIGTRAP the process that executed the break instruction.
;; Make a frame that Rexit in entry.S expects.
;;
move $brp, [$sp=$sp-16] ; Push BRP while faking a cpu status record.
push $srp ; Push subroutine return pointer.
push $dccr ; Push condition codes.
push $mof ; Push multiply overflow reg.
di ; Need to disable irq's at this point.
subq 14*4, $sp ; Make room for r0-r13.
movem $r13, [$sp] ; Push the r0-r13 registers.
push $r10 ; Push orig_r10.
clear.d [$sp=$sp-4] ; Frametype - this is a normal stackframe.
movs.w -8192,$r9 ; THREAD_SIZE == 8192
and.d $sp, $r9
move.d [$r9+TI_task], $r10
move.d [$r10+TASK_pid], $r10 ; current->pid as arg1.
moveq 5, $r11 ; SIGTRAP as arg2.
jsr sys_kill
jump ret_from_intr ; Use the return routine for interrupts.
gdb_handle_breakpoint:
push $dccr
push $r0
#ifdef CONFIG_ETRAX_KGDB
move $dccr, $r0 ; U-flag not affected by previous insns.
btstq 8, $r0 ; Test the U-flag.
bmi _ugdb_handle_breakpoint ; Go to user mode debugging.
nop ; Empty delay slot (cannot pop r0 here).
pop $r0 ; Restore r0.
ba kgdb_handle_breakpoint ; Go to kernel debugging.
pop $dccr ; Restore dccr in delay slot.
#endif
_ugdb_handle_breakpoint:
move $brp, $r0 ; Use r0 temporarily for calculation.
subq 2, $r0 ; Set to address of previous instruction.
move $r0, $brp
pop $r0 ; Restore r0.
ba do_sigtrap ; SIGTRAP the offending process.
pop $dccr ; Restore dccr in delay slot.
.data
hw_bp_trigs:
.space 64*4
hw_bp_trig_ptr:
.dword hw_bp_trigs
.section .rodata,"a"
sys_call_table:
.long sys_restart_syscall /* 0 - old "setup()" system call, used for restarting */
.long sys_exit
.long sys_fork
.long sys_read
.long sys_write
.long sys_open /* 5 */
.long sys_close
.long sys_waitpid
.long sys_creat
.long sys_link
.long sys_unlink /* 10 */
.long sys_execve
.long sys_chdir
.long sys_time
.long sys_mknod
.long sys_chmod /* 15 */
.long sys_lchown16
.long sys_ni_syscall /* old break syscall holder */
.long sys_stat
.long sys_lseek
.long sys_getpid /* 20 */
.long sys_mount
.long sys_oldumount
.long sys_setuid16
.long sys_getuid16
.long sys_stime /* 25 */
.long sys_ptrace
.long sys_alarm
.long sys_fstat
.long sys_pause
.long sys_utime /* 30 */
.long sys_ni_syscall /* old stty syscall holder */
.long sys_ni_syscall /* old gtty syscall holder */
.long sys_access
.long sys_nice
.long sys_ni_syscall /* 35 old ftime syscall holder */
.long sys_sync
.long sys_kill
.long sys_rename
.long sys_mkdir
.long sys_rmdir /* 40 */
.long sys_dup
.long sys_pipe
.long sys_times
.long sys_ni_syscall /* old prof syscall holder */
.long sys_brk /* 45 */
.long sys_setgid16
.long sys_getgid16
.long sys_signal
.long sys_geteuid16
.long sys_getegid16 /* 50 */
.long sys_acct
.long sys_umount /* recycled never used phys( */
.long sys_ni_syscall /* old lock syscall holder */
.long sys_ioctl
.long sys_fcntl /* 55 */
.long sys_ni_syscall /* old mpx syscall holder */
.long sys_setpgid
.long sys_ni_syscall /* old ulimit syscall holder */
.long sys_ni_syscall /* old sys_olduname holder */
.long sys_umask /* 60 */
.long sys_chroot
.long sys_ustat
.long sys_dup2
.long sys_getppid
.long sys_getpgrp /* 65 */
.long sys_setsid
.long sys_sigaction
.long sys_sgetmask
.long sys_ssetmask
.long sys_setreuid16 /* 70 */
.long sys_setregid16
.long sys_sigsuspend
.long sys_sigpending
.long sys_sethostname
.long sys_setrlimit /* 75 */
.long sys_old_getrlimit
.long sys_getrusage
.long sys_gettimeofday
.long sys_settimeofday
.long sys_getgroups16 /* 80 */
.long sys_setgroups16
.long sys_select /* was old_select in Linux/E100 */
.long sys_symlink
.long sys_lstat
.long sys_readlink /* 85 */
.long sys_uselib
.long sys_swapon
.long sys_reboot
.long old_readdir
.long old_mmap /* 90 */
.long sys_munmap
.long sys_truncate
.long sys_ftruncate
.long sys_fchmod
.long sys_fchown16 /* 95 */
.long sys_getpriority
.long sys_setpriority
.long sys_ni_syscall /* old profil syscall holder */
.long sys_statfs
.long sys_fstatfs /* 100 */
.long sys_ni_syscall /* sys_ioperm in i386 */
.long sys_socketcall
.long sys_syslog
.long sys_setitimer
.long sys_getitimer /* 105 */
.long sys_newstat
.long sys_newlstat
.long sys_newfstat
.long sys_ni_syscall /* old sys_uname holder */
.long sys_ni_syscall /* sys_iopl in i386 */
.long sys_vhangup
.long sys_ni_syscall /* old "idle" system call */
.long sys_ni_syscall /* vm86old in i386 */
.long sys_wait4
.long sys_swapoff /* 115 */
.long sys_sysinfo
.long sys_ipc
.long sys_fsync
.long sys_sigreturn
.long sys_clone /* 120 */
.long sys_setdomainname
.long sys_newuname
.long sys_ni_syscall /* sys_modify_ldt */
.long sys_adjtimex
.long sys_mprotect /* 125 */
.long sys_sigprocmask
.long sys_ni_syscall /* old "create_module" */
.long sys_init_module
.long sys_delete_module
.long sys_ni_syscall /* 130: old "get_kernel_syms" */
.long sys_quotactl
.long sys_getpgid
.long sys_fchdir
.long sys_bdflush
.long sys_sysfs /* 135 */
.long sys_personality
.long sys_ni_syscall /* for afs_syscall */
.long sys_setfsuid16
.long sys_setfsgid16
.long sys_llseek /* 140 */
.long sys_getdents
.long sys_select
.long sys_flock
.long sys_msync
.long sys_readv /* 145 */
.long sys_writev
.long sys_getsid
.long sys_fdatasync
.long sys_sysctl
.long sys_mlock /* 150 */
.long sys_munlock
.long sys_mlockall
.long sys_munlockall
.long sys_sched_setparam
.long sys_sched_getparam /* 155 */
.long sys_sched_setscheduler
.long sys_sched_getscheduler
.long sys_sched_yield
.long sys_sched_get_priority_max
.long sys_sched_get_priority_min /* 160 */
.long sys_sched_rr_get_interval
.long sys_nanosleep
.long sys_mremap
.long sys_setresuid16
.long sys_getresuid16 /* 165 */
.long sys_ni_syscall /* sys_vm86 */
.long sys_ni_syscall /* Old sys_query_module */
.long sys_poll
.long sys_nfsservctl
.long sys_setresgid16 /* 170 */
.long sys_getresgid16
.long sys_prctl
.long sys_rt_sigreturn
.long sys_rt_sigaction
.long sys_rt_sigprocmask /* 175 */
.long sys_rt_sigpending
.long sys_rt_sigtimedwait
.long sys_rt_sigqueueinfo
.long sys_rt_sigsuspend
.long sys_pread64 /* 180 */
.long sys_pwrite64
.long sys_chown16
.long sys_getcwd
.long sys_capget
.long sys_capset /* 185 */
.long sys_sigaltstack
.long sys_sendfile
.long sys_ni_syscall /* streams1 */
.long sys_ni_syscall /* streams2 */
.long sys_vfork /* 190 */
.long sys_getrlimit
.long sys_mmap2
.long sys_truncate64
.long sys_ftruncate64
.long sys_stat64 /* 195 */
.long sys_lstat64
.long sys_fstat64
.long sys_lchown
.long sys_getuid
.long sys_getgid /* 200 */
.long sys_geteuid
.long sys_getegid
.long sys_setreuid
.long sys_setregid
.long sys_getgroups /* 205 */
.long sys_setgroups
.long sys_fchown
.long sys_setresuid
.long sys_getresuid
.long sys_setresgid /* 210 */
.long sys_getresgid
.long sys_chown
.long sys_setuid
.long sys_setgid
.long sys_setfsuid /* 215 */
.long sys_setfsgid
.long sys_pivot_root
.long sys_mincore
.long sys_madvise
.long sys_getdents64 /* 220 */
.long sys_fcntl64
.long sys_ni_syscall /* reserved for TUX */
.long sys_ni_syscall
.long sys_gettid
.long sys_readahead /* 225 */
.long sys_setxattr
.long sys_lsetxattr
.long sys_fsetxattr
.long sys_getxattr
.long sys_lgetxattr /* 230 */
.long sys_fgetxattr
.long sys_listxattr
.long sys_llistxattr
.long sys_flistxattr
.long sys_removexattr /* 235 */
.long sys_lremovexattr
.long sys_fremovexattr
.long sys_tkill
.long sys_sendfile64
.long sys_futex /* 240 */
.long sys_sched_setaffinity
.long sys_sched_getaffinity
.long sys_ni_syscall /* sys_set_thread_area */
.long sys_ni_syscall /* sys_get_thread_area */
.long sys_io_setup /* 245 */
.long sys_io_destroy
.long sys_io_getevents
.long sys_io_submit
.long sys_io_cancel
.long sys_fadvise64 /* 250 */
.long sys_ni_syscall
.long sys_exit_group
.long sys_lookup_dcookie
.long sys_epoll_create
.long sys_epoll_ctl /* 255 */
.long sys_epoll_wait
.long sys_remap_file_pages
.long sys_set_tid_address
.long sys_timer_create
.long sys_timer_settime /* 260 */
.long sys_timer_gettime
.long sys_timer_getoverrun
.long sys_timer_delete
.long sys_clock_settime
.long sys_clock_gettime /* 265 */
.long sys_clock_getres
.long sys_clock_nanosleep
.long sys_statfs64
.long sys_fstatfs64
.long sys_tgkill /* 270 */
.long sys_utimes
.long sys_fadvise64_64
.long sys_ni_syscall /* sys_vserver */
.long sys_ni_syscall /* sys_mbind */
.long sys_ni_syscall /* 275 sys_get_mempolicy */
.long sys_ni_syscall /* sys_set_mempolicy */
.long sys_mq_open
.long sys_mq_unlink
.long sys_mq_timedsend
.long sys_mq_timedreceive /* 280 */
.long sys_mq_notify
.long sys_mq_getsetattr
.long sys_ni_syscall /* reserved for kexec */
.long sys_waitid
.long sys_ni_syscall /* 285 */ /* available */
.long sys_add_key
.long sys_request_key
.long sys_keyctl
/*
* NOTE!! This doesn't have to be exact - we just have
* to make sure we have _enough_ of the "sys_ni_syscall"
* entries. Don't panic if you notice that this hasn't
* been shrunk every time we add a new system call.
*/
.rept NR_syscalls-(.-sys_call_table)/4
.long sys_ni_syscall
.endr
