entry.S
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- /* $Id: entry.S,v 1.39 2002/04/24 00:46:45 bjornw 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 1.39 2002/04/24 00:46:45 bjornw
- * Added sys_tkill
- *
- * Revision 1.38 2002/01/16 15:15:30 bjornw
- * Use a C-code compatible watchdog reset when NICE_DOGGY is enabled
- *
- * 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 explicitely (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/config.h>
- #include <linux/linkage.h>
- #include <linux/sys.h>
- #include <asm/unistd.h>
- #include <asm/sv_addr_ag.h>
- #include <asm/errno.h>
-
- ;; functions exported from this file
-
- .globl system_call
- .globl ret_from_intr
- .globl ret_from_sys_call
- .globl resume
- .globl multiple_interrupt
- .globl hwbreakpoint
- .globl IRQ1_interrupt
- .globl timer_interrupt
- .globl timer_shortcut
- .globl spurious_interrupt
- .globl hw_bp_trigs
- .globl mmu_bus_fault
- .globl do_sigtrap
- .globl gdb_handle_breakpoint
-
- .globl sys_call_table
-
- ;; Get values and offsets into various structs. The file isn't
- ;; suitable for consumption by the preprocessor, so don't use
- ;; #include.
- .include "entryoffsets.s"
- ;; process bits for ptrace. FIXME: Should be in a header file.
- PT_TRACESYS_BIT = 1
- ;; below are various parts of system_call which are not in the fast-path
-
- ;; handle software irqs
-
- _handle_softirq:
- move.d $r9, $r1
- jsr do_softirq ; call the C routine for softirq handling
- move.d $r1, $r9
- ;; fall-through
-
- ret_from_intr:
- ;; check for resched only 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 + LDCCR], $r0; regs->dccr
- btstq 8, $r0 ; U-flag
- bpl _Rexit ; go back directly
- nop
- ba _ret_with_reschedule ; go back but check schedule and signals first
- nop
- _reschedule:
- ;; keep r9 intact
- move.d $r9, $r1
- jsr schedule
- ba ret_from_sys_call
- move.d $r1, $r9
- ;; return but call do_signal first
- _signal_return:
- ei ; we can get here from an interrupt
- move.d $r9, $r10 ; do_signals syscall/irq param
- moveq 0, $r11 ; oldset param - 0 in this case
- move.d $sp, $r12 ; another argument to do_signal (the regs param)
- jsr do_signal ; arch/cris/kernel/signal.c
- 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+LR10] ; 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+LTASK_PTRACE], $r0
- btstq PT_TRACESYS_BIT, $r0
- bmi _tracesys
- nop
- ;; 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+LR10] ; 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
-
- ;; check if any bottom halves need service
-
- test.d [irq_stat] ; softirq_pending
- bne _handle_softirq
- nop
- _ret_with_reschedule:
- ;; first get the current task-struct pointer (see top for defs)
- move.d $sp, $r0
- and.d -8192, $r0 ; THREAD_SIZE == 8192
-
- ;; see if we want to reschedule into another process
-
- test.d [$r0+LTASK_NEEDRESCHED]
- bne _reschedule
- nop
- ;; see if we need to run signal checks (important that r9 is intact here)
- test.d [$r0+LTASK_SIGPENDING]
- bne _signal_return
- 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
- _tracesys:
- ;; this first invocation of syscall_trace _requires_ that
- ;; LR10 in the frame contains -ENOSYS (as is set in the beginning
- ;; of system_call).
- jsr syscall_trace
- ;; now we should more or less do the same things as in the system_call
- ;; but since our argument regs got clobbered during syscall_trace and
- ;; because syscall_trace might want to alter them, we need to reload them
- ;; from the stack-frame as we use them.
- ;; check for sanity in the requested syscall number
- move.d [$sp+LR9], $r9
- movs.w -ENOSYS, $r10
- cmpu.w NR_syscalls, $r9
- bcc 1f
- lslq 2, $r9 ; multiply by 4, in the delay slot
- ;; read the system call vector entry into r9
-
- move.d [$r9+sys_call_table], $r9
- ;; restore r10, r11, r12, r13, mof and srp into the needed registers
- move.d [$sp+LORIG_R10], $r10 ; LR10 is already filled with -ENOSYS.
- move.d [$sp+LR11], $r11
- move.d [$sp+LR12], $r12
- move.d [$sp+LR13], $r13
- move [$sp+LMOF], $mof
- move [$sp+LSRP], $srp
- ;; as a bonus 7th parameter, we give the location on the stack
- ;; of the register structure itself. some syscalls need this.
- push $sp
-
- ;; the fifth and sixth parameters needs to be put on the stack for
- ;; the system call to find them
- push $srp
- push $mof
- jsr $r9 ; actually call the system-call
- addq 3*4, $sp ; pop the srp, mof and regs parameters
- 1: move.d $r10, [$sp+LR10]; save the return value
- ;; second call of syscall_trace, to let it grab the results
-
- jsr syscall_trace
- moveq 1, $r9 ; "parameter" to ret_from_sys_call to show it was a sys call
- ba ret_from_sys_call
- 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+LTHREAD_DCCR] ; save irq enable state
- di
- move $usp, [$r10+LTHREAD_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+LTHREAD_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 task ptr from stackpointer
- add.d $r12, $r11 ; find the new tasks tss
- move.d [$r11+LTHREAD_KSP], $sp ; switch into the new stackframe by restoring kernel sp
- movem [$sp+], $r9 ; restore non-scratch registers and R9.
- move [$r11+LTHREAD_USP], $usp ; restore user-mode stackpointer
-
- move [$r11+LTHREAD_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:
- sbfs [$sp=$sp-16] ; push the internal CPU status
- ;; 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..
- 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/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
- #if 0
- hwbreakpoint:
- push $dccr
- di
- push $r10
- push $r11
- push $r12
- push $r13
- clearf b
- move $brp,$r11
- move.d [hw_bp_msg],$r10
- jsr printk
- setf b
- pop $r13
- pop $r12
- pop $r11
- pop $r10
- pop $dccr
- retb
- nop
- #else
- hwbreakpoint:
- push $dccr
- di
- #if 1
- push $r10
- push $r11
- move.d [hw_bp_trig_ptr],$r10
- move.d [$r10],$r11
- cmp.d 42,$r11
- beq 1f
- nop
- move $brp,$r11
- move.d $r11,[$r10+]
- move.d $r10,[hw_bp_trig_ptr]
- 1: pop $r11
- pop $r10
- #endif
- pop $dccr
- retb
- nop
- #endif
-
- IRQ1_interrupt:
- #if defined(CONFIG_ETRAX_WATCHDOG) && !defined(CONFIG_SVINTO_SIM)
- ;; If we receive a watchdog interrupt while it is not expected, then set
- ;; up a canonical frame and dump register contents before dying.
- ;; 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
- ;; We don't check that we actually were bit by the watchdog as opposed to
- ;; an external NMI, since there is currently no handler for external NMI.
- ;; 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 watchdogn "
- .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
-
- move.d irq_shortcuts + 8, $r1
- 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
- 1:
- btst $r2, $r0 ; check for the irq given by bit r2
- bmi _do_shortcut ; actually do the shortcut
- nop
- addq 1, $r2 ; next vector bit
- addq 4, $r1 ; next vector
- cmp.b 32, $r2
- bne 1b ; process all irq's up to and including number 31
- nop
-
- ;; strange, we didn't get any set vector bits.. oh well, just return
-
- ba _Rexit
- nop
- _do_shortcut:
- test.d [$r1]
- beq _Rexit
- nop
- jump [$r1] ; jump to the irq handlers shortcut
- 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+LTASK_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
- /*
- * This is the mechanism for creating a new kernel thread.
- *
- * NOTE! Only a kernel-only process (i.e. the swapper or direct descendants
- * who haven't done an "execve()") should use this: it will work within
- * a system call from a "real" process, but the process memory space will
- * not be free'd until both the parent and the child have exited.
- *
- * This *can* be done in C with an single-asm-wrapped-in-a-function, but you
- * get more or less gross code. The safer you make the asm-constraints,
- * the grosser the code, at least with the gcc version in cris-dist-1.13.
- */
- /* int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags) */
- /* r10 r11 r12 */
- .text
- .global kernel_thread
- kernel_thread:
- /* Save ARG for later. */
- move.d $r11, $r13
- /* r11 is argument 2 to clone, the flags */
- move.d $r12, $r11
- or.w LCLONE_VM, $r11
- /* Save FN for later. */
- move.d $r10, $r12
- /* r9 contains syscall number, to sys_clone */
- movu.w __NR_clone, $r9
- /* r10 is argument 1 to clone */
- clear.d $r10
-
- /* call sys_clone, this will fork */
- break 13
- /* parent or child? child returns 0 here. */
- test.d $r10
- /* jump if parent */
- bne 1f
- nop /* delay slot */
- /* set argument to function to call */
- move.d $r13, $r10
- /* call specified function */
- jsr $r12
- /* If we ever return from the function, something bad has happened. */
- /* r9 is sys_exit syscall number */
- movu.w __NR_exit, $r9
- /* Give a really bad exit-value */
- moveq -1, $r10
- /* call sys_exit, killing the child */
- break 13
- 1:
- ret
- nop /* delay slot */
- .section .rodata,"a"
- sys_call_table:
- .long SYMBOL_NAME(sys_ni_syscall) /* 0 - old "setup()" system call*/
- .long SYMBOL_NAME(sys_exit)
- .long SYMBOL_NAME(sys_fork)
- .long SYMBOL_NAME(sys_read)
- .long SYMBOL_NAME(sys_write)
- .long SYMBOL_NAME(sys_open) /* 5 */
- .long SYMBOL_NAME(sys_close)
- .long SYMBOL_NAME(sys_waitpid)
- .long SYMBOL_NAME(sys_creat)
- .long SYMBOL_NAME(sys_link)
- .long SYMBOL_NAME(sys_unlink) /* 10 */
- .long SYMBOL_NAME(sys_execve)
- .long SYMBOL_NAME(sys_chdir)
- .long SYMBOL_NAME(sys_time)
- .long SYMBOL_NAME(sys_mknod)
- .long SYMBOL_NAME(sys_chmod) /* 15 */
- .long SYMBOL_NAME(sys_lchown16)
- .long SYMBOL_NAME(sys_ni_syscall) /* old break syscall holder */
- .long SYMBOL_NAME(sys_stat)
- .long SYMBOL_NAME(sys_lseek)
- .long SYMBOL_NAME(sys_getpid) /* 20 */
- .long SYMBOL_NAME(sys_mount)
- .long SYMBOL_NAME(sys_oldumount)
- .long SYMBOL_NAME(sys_setuid16)
- .long SYMBOL_NAME(sys_getuid16)
- .long SYMBOL_NAME(sys_stime) /* 25 */
- .long SYMBOL_NAME(sys_ptrace)
- .long SYMBOL_NAME(sys_alarm)
- .long SYMBOL_NAME(sys_fstat)
- .long SYMBOL_NAME(sys_pause)
- .long SYMBOL_NAME(sys_utime) /* 30 */
- .long SYMBOL_NAME(sys_ni_syscall) /* old stty syscall holder */
- .long SYMBOL_NAME(sys_ni_syscall) /* old gtty syscall holder */
- .long SYMBOL_NAME(sys_access)
- .long SYMBOL_NAME(sys_nice)
- .long SYMBOL_NAME(sys_ni_syscall) /* 35 old ftime syscall holder */
- .long SYMBOL_NAME(sys_sync)
- .long SYMBOL_NAME(sys_kill)
- .long SYMBOL_NAME(sys_rename)
- .long SYMBOL_NAME(sys_mkdir)
- .long SYMBOL_NAME(sys_rmdir) /* 40 */
- .long SYMBOL_NAME(sys_dup)
- .long SYMBOL_NAME(sys_pipe)
- .long SYMBOL_NAME(sys_times)
- .long SYMBOL_NAME(sys_ni_syscall) /* old prof syscall holder */
- .long SYMBOL_NAME(sys_brk) /* 45 */
- .long SYMBOL_NAME(sys_setgid16)
- .long SYMBOL_NAME(sys_getgid16)
- .long SYMBOL_NAME(sys_signal)
- .long SYMBOL_NAME(sys_geteuid16)
- .long SYMBOL_NAME(sys_getegid16) /* 50 */
- .long SYMBOL_NAME(sys_acct)
- .long SYMBOL_NAME(sys_umount) /* recycled never used phys() */
- .long SYMBOL_NAME(sys_ni_syscall) /* old lock syscall holder */
- .long SYMBOL_NAME(sys_ioctl)
- .long SYMBOL_NAME(sys_fcntl) /* 55 */
- .long SYMBOL_NAME(sys_ni_syscall) /* old mpx syscall holder */
- .long SYMBOL_NAME(sys_setpgid)
- .long SYMBOL_NAME(sys_ni_syscall) /* old ulimit syscall holder */
- .long SYMBOL_NAME(sys_ni_syscall) /* old sys_olduname holder */
- .long SYMBOL_NAME(sys_umask) /* 60 */
- .long SYMBOL_NAME(sys_chroot)
- .long SYMBOL_NAME(sys_ustat)
- .long SYMBOL_NAME(sys_dup2)
- .long SYMBOL_NAME(sys_getppid)
- .long SYMBOL_NAME(sys_getpgrp) /* 65 */
- .long SYMBOL_NAME(sys_setsid)
- .long SYMBOL_NAME(sys_sigaction)
- .long SYMBOL_NAME(sys_sgetmask)
- .long SYMBOL_NAME(sys_ssetmask)
- .long SYMBOL_NAME(sys_setreuid16) /* 70 */
- .long SYMBOL_NAME(sys_setregid16)
- .long SYMBOL_NAME(sys_sigsuspend)
- .long SYMBOL_NAME(sys_sigpending)
- .long SYMBOL_NAME(sys_sethostname)
- .long SYMBOL_NAME(sys_setrlimit) /* 75 */
- .long SYMBOL_NAME(sys_old_getrlimit)
- .long SYMBOL_NAME(sys_getrusage)
- .long SYMBOL_NAME(sys_gettimeofday)
- .long SYMBOL_NAME(sys_settimeofday)
- .long SYMBOL_NAME(sys_getgroups16) /* 80 */
- .long SYMBOL_NAME(sys_setgroups16)
- .long SYMBOL_NAME(sys_select) /* was old_select in Linux/E100 */
- .long SYMBOL_NAME(sys_symlink)
- .long SYMBOL_NAME(sys_lstat)
- .long SYMBOL_NAME(sys_readlink) /* 85 */
- .long SYMBOL_NAME(sys_uselib)
- .long SYMBOL_NAME(sys_swapon)
- .long SYMBOL_NAME(sys_reboot)
- .long SYMBOL_NAME(old_readdir)
- .long SYMBOL_NAME(old_mmap) /* 90 */
- .long SYMBOL_NAME(sys_munmap)
- .long SYMBOL_NAME(sys_truncate)
- .long SYMBOL_NAME(sys_ftruncate)
- .long SYMBOL_NAME(sys_fchmod)
- .long SYMBOL_NAME(sys_fchown16) /* 95 */
- .long SYMBOL_NAME(sys_getpriority)
- .long SYMBOL_NAME(sys_setpriority)
- .long SYMBOL_NAME(sys_ni_syscall) /* old profil syscall holder */
- .long SYMBOL_NAME(sys_statfs)
- .long SYMBOL_NAME(sys_fstatfs) /* 100 */
- .long SYMBOL_NAME(sys_ni_syscall) /* sys_ioperm in i386 */
- .long SYMBOL_NAME(sys_socketcall)
- .long SYMBOL_NAME(sys_syslog)
- .long SYMBOL_NAME(sys_setitimer)
- .long SYMBOL_NAME(sys_getitimer) /* 105 */
- .long SYMBOL_NAME(sys_newstat)
- .long SYMBOL_NAME(sys_newlstat)
- .long SYMBOL_NAME(sys_newfstat)
- .long SYMBOL_NAME(sys_ni_syscall) /* old sys_uname holder */
- .long SYMBOL_NAME(sys_ni_syscall) /* sys_iopl in i386 */
- .long SYMBOL_NAME(sys_vhangup)
- .long SYMBOL_NAME(sys_ni_syscall) /* old "idle" system call */
- .long SYMBOL_NAME(sys_ni_syscall) /* vm86old in i386 */
- .long SYMBOL_NAME(sys_wait4)
- .long SYMBOL_NAME(sys_swapoff) /* 115 */
- .long SYMBOL_NAME(sys_sysinfo)
- .long SYMBOL_NAME(sys_ipc)
- .long SYMBOL_NAME(sys_fsync)
- .long SYMBOL_NAME(sys_sigreturn)
- .long SYMBOL_NAME(sys_clone) /* 120 */
- .long SYMBOL_NAME(sys_setdomainname)
- .long SYMBOL_NAME(sys_newuname)
- .long SYMBOL_NAME(sys_ni_syscall) /* TODO sys_modify_ldt - do something ?*/
- .long SYMBOL_NAME(sys_adjtimex)
- .long SYMBOL_NAME(sys_mprotect) /* 125 */
- .long SYMBOL_NAME(sys_sigprocmask)
- .long SYMBOL_NAME(sys_create_module)
- .long SYMBOL_NAME(sys_init_module)
- .long SYMBOL_NAME(sys_delete_module)
- .long SYMBOL_NAME(sys_get_kernel_syms) /* 130 */
- .long SYMBOL_NAME(sys_quotactl)
- .long SYMBOL_NAME(sys_getpgid)
- .long SYMBOL_NAME(sys_fchdir)
- .long SYMBOL_NAME(sys_bdflush)
- .long SYMBOL_NAME(sys_sysfs) /* 135 */
- .long SYMBOL_NAME(sys_personality)
- .long SYMBOL_NAME(sys_ni_syscall) /* for afs_syscall */
- .long SYMBOL_NAME(sys_setfsuid16)
- .long SYMBOL_NAME(sys_setfsgid16)
- .long SYMBOL_NAME(sys_llseek) /* 140 */
- .long SYMBOL_NAME(sys_getdents)
- .long SYMBOL_NAME(sys_select)
- .long SYMBOL_NAME(sys_flock)
- .long SYMBOL_NAME(sys_msync)
- .long SYMBOL_NAME(sys_readv) /* 145 */
- .long SYMBOL_NAME(sys_writev)
- .long SYMBOL_NAME(sys_getsid)
- .long SYMBOL_NAME(sys_fdatasync)
- .long SYMBOL_NAME(sys_sysctl)
- .long SYMBOL_NAME(sys_mlock) /* 150 */
- .long SYMBOL_NAME(sys_munlock)
- .long SYMBOL_NAME(sys_mlockall)
- .long SYMBOL_NAME(sys_munlockall)
- .long SYMBOL_NAME(sys_sched_setparam)
- .long SYMBOL_NAME(sys_sched_getparam) /* 155 */
- .long SYMBOL_NAME(sys_sched_setscheduler)
- .long SYMBOL_NAME(sys_sched_getscheduler)
- .long SYMBOL_NAME(sys_sched_yield)
- .long SYMBOL_NAME(sys_sched_get_priority_max)
- .long SYMBOL_NAME(sys_sched_get_priority_min) /* 160 */
- .long SYMBOL_NAME(sys_sched_rr_get_interval)
- .long SYMBOL_NAME(sys_nanosleep)
- .long SYMBOL_NAME(sys_mremap)
- .long SYMBOL_NAME(sys_setresuid16)
- .long SYMBOL_NAME(sys_getresuid16) /* 165 */
- .long SYMBOL_NAME(sys_ni_syscall) /* sys_vm86 */
- .long SYMBOL_NAME(sys_query_module)
- .long SYMBOL_NAME(sys_poll)
- .long SYMBOL_NAME(sys_nfsservctl)
- .long SYMBOL_NAME(sys_setresgid16) /* 170 */
- .long SYMBOL_NAME(sys_getresgid16)
- .long SYMBOL_NAME(sys_prctl)
- .long SYMBOL_NAME(sys_rt_sigreturn)
- .long SYMBOL_NAME(sys_rt_sigaction)
- .long SYMBOL_NAME(sys_rt_sigprocmask) /* 175 */
- .long SYMBOL_NAME(sys_rt_sigpending)
- .long SYMBOL_NAME(sys_rt_sigtimedwait)
- .long SYMBOL_NAME(sys_rt_sigqueueinfo)
- .long SYMBOL_NAME(sys_rt_sigsuspend)
- .long SYMBOL_NAME(sys_pread) /* 180 */
- .long SYMBOL_NAME(sys_pwrite)
- .long SYMBOL_NAME(sys_chown16)
- .long SYMBOL_NAME(sys_getcwd)
- .long SYMBOL_NAME(sys_capget)
- .long SYMBOL_NAME(sys_capset) /* 185 */
- .long SYMBOL_NAME(sys_sigaltstack)
- .long SYMBOL_NAME(sys_sendfile)
- .long SYMBOL_NAME(sys_ni_syscall) /* streams1 */
- .long SYMBOL_NAME(sys_ni_syscall) /* streams2 */
- .long SYMBOL_NAME(sys_vfork) /* 190 */
- .long SYMBOL_NAME(sys_getrlimit)
- .long SYMBOL_NAME(sys_mmap2)
- .long SYMBOL_NAME(sys_truncate64)
- .long SYMBOL_NAME(sys_ftruncate64)
- .long SYMBOL_NAME(sys_stat64) /* 195 */
- .long SYMBOL_NAME(sys_lstat64)
- .long SYMBOL_NAME(sys_fstat64)
- .long SYMBOL_NAME(sys_lchown)
- .long SYMBOL_NAME(sys_getuid)
- .long SYMBOL_NAME(sys_getgid) /* 200 */
- .long SYMBOL_NAME(sys_geteuid)
- .long SYMBOL_NAME(sys_getegid)
- .long SYMBOL_NAME(sys_setreuid)
- .long SYMBOL_NAME(sys_setregid)
- .long SYMBOL_NAME(sys_getgroups) /* 205 */
- .long SYMBOL_NAME(sys_setgroups)
- .long SYMBOL_NAME(sys_fchown)
- .long SYMBOL_NAME(sys_setresuid)
- .long SYMBOL_NAME(sys_getresuid)
- .long SYMBOL_NAME(sys_setresgid) /* 210 */
- .long SYMBOL_NAME(sys_getresgid)
- .long SYMBOL_NAME(sys_chown)
- .long SYMBOL_NAME(sys_setuid)
- .long SYMBOL_NAME(sys_setgid)
- .long SYMBOL_NAME(sys_setfsuid) /* 215 */
- .long SYMBOL_NAME(sys_setfsgid)
- .long SYMBOL_NAME(sys_pivot_root)
- .long SYMBOL_NAME(sys_mincore)
- .long SYMBOL_NAME(sys_madvise)
- .long SYMBOL_NAME(sys_getdents64) /* 220 */
- .long SYMBOL_NAME(sys_fcntl64)
- .long SYMBOL_NAME(sys_ni_syscall) /* reserved for TUX */
- .long SYMBOL_NAME(sys_ni_syscall) /* Reserved for Security */
- .long SYMBOL_NAME(sys_gettid)
- .long SYMBOL_NAME(sys_readahead) /* 225 */
- .long SYMBOL_NAME(sys_tkill)
-
- /*
- * 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 SYMBOL_NAME(sys_ni_syscall)
- .endr
-