1 files changed, 433 insertions, 0 deletions
diff --git a/arch/sh/kernel/entry-common.S b/arch/sh/kernel/entry-common.S
new file mode 100644
index 000000000000..29136a35d7c7
--- /dev/null
+++ b/arch/sh/kernel/entry-common.S
@@ -0,0 +1,433 @@
+/* $Id: entry.S,v 1.37 2004/06/11 13:02:46 doyu Exp $
+ *
+ *  linux/arch/sh/entry.S
+ *
+ *  Copyright (C) 1999, 2000, 2002  Niibe Yutaka
+ *  Copyright (C) 2003  Paul Mundt
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ */
+! NOTE:
+! GNU as (as of 2.9.1) changes bf/s into bt/s and bra, when the address
+! to be jumped is too far, but it causes illegal slot exception.
+/*      
+ * entry.S contains the system-call and fault low-level handling routines.
+ * This also contains the timer-interrupt handler, as well as all interrupts
+ * and faults that can result in a task-switch.
+ *
+ * NOTE: This code handles signal-recognition, which happens every time
+ * after a timer-interrupt and after each system call.
+ *
+ * NOTE: This code uses a convention that instructions in the delay slot
+ * of a transfer-control instruction are indented by an extra space, thus:
+ *
+ *    jmp       @k0         ! control-transfer instruction
+ *     ldc      k1, ssr     ! delay slot
+ *
+ * Stack layout in 'ret_from_syscall':
+ *      ptrace needs to have all regs on the stack.
+ *      if the order here is changed, it needs to be
+ *      updated in ptrace.c and ptrace.h
+ *
+ *      r0
+ *      ...
+ *      r15 = stack pointer
+ *      spc
+ *      pr
+ *      ssr
+ *      gbr
+ *      mach
+ *      macl
+ *      syscall #
+ *
+ */
+#if defined(CONFIG_PREEMPT)
+#  define preempt_stop()        cli
+#else
+#  define preempt_stop()
+#  define resume_kernel         __restore_all
+#endif
+#if defined(CONFIG_SH_STANDARD_BIOS) || defined(CONFIG_SH_KGDB)
+! Handle kernel debug if either kgdb (SW) or gdb-stub (FW) is present.
+! If both are configured, handle the debug traps (breakpoints) in SW,
+! but still allow BIOS traps to FW.
+        .align  2
+debug_kernel:
+#if defined(CONFIG_SH_STANDARD_BIOS) && defined(CONFIG_SH_KGDB)
+        /* Force BIOS call to FW (debug_trap put TRA in r8) */
+        mov     r8,r0
+        shlr2   r0
+        cmp/eq  #0x3f,r0
+        bt      debug_kernel_fw
+#endif /* CONFIG_SH_STANDARD_BIOS && CONFIG_SH_KGDB */
+debug_enter:            
+#if defined(CONFIG_SH_KGDB)
+        /* Jump to kgdb, pass stacked regs as arg */
+debug_kernel_sw:
+        mov.l   3f, r0
+        jmp     @r0
+         mov    r15, r4
+        .align  2
+3:      .long   kgdb_handle_exception
+#endif /* CONFIG_SH_KGDB */
+#endif /* CONFIG_SH_STANDARD_BIOS || CONFIG_SH_KGDB */
+        .align  2
+debug_trap:     
+#if defined(CONFIG_SH_STANDARD_BIOS) || defined(CONFIG_SH_KGDB)
+        mov     #OFF_SR, r0
+        mov.l   @(r0,r15), r0           ! get status register
+        shll    r0
+        shll    r0                      ! kernel space?
+        bt/s    debug_kernel
+#endif
+         mov.l  @r15, r0                ! Restore R0 value
+        mov.l   1f, r8
+        jmp     @r8
+         nop
+        .align  2
+ENTRY(exception_error)
+        !
+#ifdef CONFIG_TRACE_IRQFLAGS
+        mov.l   3f, r0
+        jsr     @r0
+         nop
+#endif
+        sti
+        mov.l   2f, r0
+        jmp     @r0
+         nop
+!
+        .align  2
+1:      .long   break_point_trap_software
+2:      .long   do_exception_error
+#ifdef CONFIG_TRACE_IRQFLAGS
+3:      .long   trace_hardirqs_on
+#endif
+        .align  2
+ret_from_exception:
+        preempt_stop()
+#ifdef CONFIG_TRACE_IRQFLAGS
+        mov.l   4f, r0
+        jsr     @r0
+         nop
+#endif
+ENTRY(ret_from_irq)
+        !
+        mov     #OFF_SR, r0
+        mov.l   @(r0,r15), r0   ! get status register
+        shll    r0
+        shll    r0              ! kernel space?
+        get_current_thread_info r8, r0
+        bt      resume_kernel   ! Yes, it's from kernel, go back soon
+#ifdef CONFIG_PREEMPT
+        bra     resume_userspace
+         nop
+ENTRY(resume_kernel)
+        mov.l   @(TI_PRE_COUNT,r8), r0  ! current_thread_info->preempt_count
+        tst     r0, r0
+        bf      noresched
+need_resched:
+        mov.l   @(TI_FLAGS,r8), r0      ! current_thread_info->flags
+        tst     #_TIF_NEED_RESCHED, r0  ! need_resched set?
+        bt      noresched
+        mov     #OFF_SR, r0
+        mov.l   @(r0,r15), r0           ! get status register
+        and     #0xf0, r0               ! interrupts off (exception path)?
+        cmp/eq  #0xf0, r0
+        bt      noresched
+        mov.l   1f, r0
+        mov.l   r0, @(TI_PRE_COUNT,r8)
+#ifdef CONFIG_TRACE_IRQFLAGS
+        mov.l   3f, r0
+        jsr     @r0
+         nop
+#endif
+        sti
+        mov.l   2f, r0
+        jsr     @r0
+         nop
+        mov     #0, r0
+        mov.l   r0, @(TI_PRE_COUNT,r8)
+        cli
+#ifdef CONFIG_TRACE_IRQFLAGS
+        mov.l   4f, r0
+        jsr     @r0
+         nop
+#endif
+        bra     need_resched
+         nop
+noresched:
+        bra     __restore_all
+         nop
+        .align 2
+1:      .long   PREEMPT_ACTIVE
+2:      .long   schedule
+#ifdef CONFIG_TRACE_IRQFLAGS
+3:      .long   trace_hardirqs_on
+4:      .long   trace_hardirqs_off
+#endif
+#endif
+ENTRY(resume_userspace)
+        ! r8: current_thread_info
+        cli
+#ifdef CONFIG_TRACE_IRQFLAGS
+        mov.l   5f, r0
+        jsr     @r0
+         nop
+#endif
+        mov.l   @(TI_FLAGS,r8), r0              ! current_thread_info->flags
+        tst     #_TIF_WORK_MASK, r0
+        bt/s    __restore_all
+         tst    #_TIF_NEED_RESCHED, r0
+        .align  2
+work_pending:
+        ! r0: current_thread_info->flags
+        ! r8: current_thread_info
+        ! t:  result of "tst    #_TIF_NEED_RESCHED, r0"
+        bf/s    work_resched
+         tst    #(_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK), r0
+work_notifysig:
+        bt/s    __restore_all
+         mov    r15, r4
+        mov     r12, r5         ! set arg1(save_r0)
+        mov     r0, r6
+        mov.l   2f, r1
+        mov.l   3f, r0
+        jmp     @r1
+         lds    r0, pr
+work_resched:
+#ifndef CONFIG_PREEMPT
+        ! gUSA handling
+        mov.l   @(OFF_SP,r15), r0       ! get user space stack pointer
+        mov     r0, r1
+        shll    r0
+        bf/s    1f
+         shll   r0
+        bf/s    1f
+         mov    #OFF_PC, r0
+        !                                 SP >= 0xc0000000 : gUSA mark
+        mov.l   @(r0,r15), r2           ! get user space PC (program counter)
+        mov.l   @(OFF_R0,r15), r3       ! end point
+        cmp/hs  r3, r2                  ! r2 >= r3? 
+        bt      1f
+        add     r3, r1                  ! rewind point #2
+        mov.l   r1, @(r0,r15)           ! reset PC to rewind point #2
+        !
+1:
+#endif
+        mov.l   1f, r1
+        jsr     @r1                             ! schedule
+         nop
+        cli
+#ifdef CONFIG_TRACE_IRQFLAGS
+        mov.l   5f, r0
+        jsr     @r0
+         nop
+#endif
+        !
+        mov.l   @(TI_FLAGS,r8), r0              ! current_thread_info->flags
+        tst     #_TIF_WORK_MASK, r0
+        bt      __restore_all
+        bra     work_pending
+         tst    #_TIF_NEED_RESCHED, r0
+        .align  2
+1:      .long   schedule
+2:      .long   do_notify_resume
+3:      .long   restore_all
+#ifdef CONFIG_TRACE_IRQFLAGS
+4:      .long   trace_hardirqs_on
+5:      .long   trace_hardirqs_off
+#endif
+        .align  2
+syscall_exit_work:
+        ! r0: current_thread_info->flags
+        ! r8: current_thread_info
+        tst     #_TIF_SYSCALL_TRACE, r0
+        bt/s    work_pending
+         tst    #_TIF_NEED_RESCHED, r0
+#ifdef CONFIG_TRACE_IRQFLAGS
+        mov.l   5f, r0
+        jsr     @r0
+         nop
+#endif
+        sti
+        ! XXX setup arguments...
+        mov.l   4f, r0                  ! do_syscall_trace
+        jsr     @r0
+         nop
+        bra     resume_userspace
+         nop
+        .align  2
+syscall_trace_entry:
+        !                       Yes it is traced.
+        ! XXX setup arguments...
+        mov.l   4f, r11         ! Call do_syscall_trace which notifies
+        jsr     @r11            ! superior (will chomp R[0-7])
+         nop
+        !                       Reload R0-R4 from kernel stack, where the
+        !                       parent may have modified them using
+        !                       ptrace(POKEUSR).  (Note that R0-R2 are
+        !                       used by the system call handler directly
+        !                       from the kernel stack anyway, so don't need
+        !                       to be reloaded here.)  This allows the parent
+        !                       to rewrite system calls and args on the fly.
+        mov.l   @(OFF_R4,r15), r4   ! arg0
+        mov.l   @(OFF_R5,r15), r5
+        mov.l   @(OFF_R6,r15), r6
+        mov.l   @(OFF_R7,r15), r7   ! arg3
+        mov.l   @(OFF_R3,r15), r3   ! syscall_nr
+        !
+        mov.l   2f, r10                 ! Number of syscalls
+        cmp/hs  r10, r3
+        bf      syscall_call
+        mov     #-ENOSYS, r0
+        bra     syscall_exit
+         mov.l  r0, @(OFF_R0,r15)       ! Return value
+__restore_all:
+        mov.l   1f, r0
+        jmp     @r0
+         nop
+        .align  2
+1:      .long   restore_all
+        .align  2
+not_syscall_tra:        
+        bra     debug_trap
+         nop
+        .align  2
+syscall_badsys:                 ! Bad syscall number
+        mov     #-ENOSYS, r0
+        bra     resume_userspace
+         mov.l  r0, @(OFF_R0,r15)       ! Return value
+        
+/*
+ * Syscall interface:
+ *
+ *      Syscall #: R3
+ *      Arguments #0 to #3: R4--R7
+ *      Arguments #4 to #6: R0, R1, R2
+ *      TRA: (number of arguments + 0x10) x 4
+ *
+ * This code also handles delegating other traps to the BIOS/gdb stub
+ * according to:
+ *
+ * Trap number
+ * (TRA>>2)         Purpose
+ * --------         -------
+ * 0x0-0xf          old syscall ABI
+ * 0x10-0x1f        new syscall ABI
+ * 0x20-0xff        delegated through debug_trap to BIOS/gdb stub.
+ *
+ * Note: When we're first called, the TRA value must be shifted
+ * right 2 bits in order to get the value that was used as the "trapa"
+ * argument.
+ */
+        .align  2
+        .globl  ret_from_fork
+ret_from_fork:
+        mov.l   1f, r8
+        jsr     @r8
+         mov    r0, r4
+        bra     syscall_exit
+         nop
+        .align  2
+1:      .long   schedule_tail
+        !
+ENTRY(system_call)
+#if !defined(CONFIG_CPU_SH2)
+        mov.l   1f, r9
+        mov.l   @r9, r8         ! Read from TRA (Trap Address) Register
+#endif
+        !
+        ! Is the trap argument >= 0x20? (TRA will be >= 0x80)
+        mov     #0x7f, r9
+        cmp/hi  r9, r8
+        bt/s    not_syscall_tra
+         mov    #OFF_TRA, r9
+        add     r15, r9
+        mov.l   r8, @r9                 ! set TRA value to tra
+#ifdef CONFIG_TRACE_IRQFLAGS
+        mov.l   5f, r10
+        jsr     @r10
+         nop
+#endif
+        sti
+        !
+        get_current_thread_info r8, r10
+        mov.l   @(TI_FLAGS,r8), r8
+        mov     #_TIF_SYSCALL_TRACE, r10
+        tst     r10, r8
+        bf      syscall_trace_entry
+        !
+        mov.l   2f, r8                  ! Number of syscalls
+        cmp/hs  r8, r3
+        bt      syscall_badsys
+        !
+syscall_call:
+        shll2   r3              ! x4
+        mov.l   3f, r8          ! Load the address of sys_call_table
+        add     r8, r3
+        mov.l   @r3, r8
+        jsr     @r8             ! jump to specific syscall handler
+         nop
+        mov.l   @(OFF_R0,r15), r12              ! save r0
+        mov.l   r0, @(OFF_R0,r15)               ! save the return value
+        !
+syscall_exit:
+        cli
+#ifdef CONFIG_TRACE_IRQFLAGS
+        mov.l   6f, r0
+        jsr     @r0
+         nop
+#endif
+        !
+        get_current_thread_info r8, r0
+        mov.l   @(TI_FLAGS,r8), r0              ! current_thread_info->flags
+        tst     #_TIF_ALLWORK_MASK, r0
+        bf      syscall_exit_work
+        bra     __restore_all
+         nop
+        .align  2
+#if !defined(CONFIG_CPU_SH2)
+1:      .long   TRA
+#endif
+2:      .long   NR_syscalls
+3:      .long   sys_call_table
+4:      .long   do_syscall_trace
+#ifdef CONFIG_TRACE_IRQFLAGS
+5:      .long   trace_hardirqs_on
+6:      .long   trace_hardirqs_off
+#endif

diff --git a/arch/sh/kernel/entry-common.S b/arch/sh/kernel/entry-common.S new file mode 100644 index 000000000000..29136a35d7c7 --- /dev/null +++ b/arch/sh/kernel/entry-common.S
@@ -0,0 +1,433 @@
	1	/* $Id: entry.S,v 1.37 2004/06/11 13:02:46 doyu Exp $
	2	*
	3	* linux/arch/sh/entry.S
	4	*
	5	* Copyright (C) 1999, 2000, 2002 Niibe Yutaka
	6	* Copyright (C) 2003 Paul Mundt
	7	*
	8	* This file is subject to the terms and conditions of the GNU General Public
	9	* License. See the file "COPYING" in the main directory of this archive
	10	* for more details.
	11	*
	12	*/
	13
	14	! NOTE:
	15	! GNU as (as of 2.9.1) changes bf/s into bt/s and bra, when the address
	16	! to be jumped is too far, but it causes illegal slot exception.
	17
	18	/*
	19	* entry.S contains the system-call and fault low-level handling routines.
	20	* This also contains the timer-interrupt handler, as well as all interrupts
	21	* and faults that can result in a task-switch.
	22	*
	23	* NOTE: This code handles signal-recognition, which happens every time
	24	* after a timer-interrupt and after each system call.
	25	*
	26	* NOTE: This code uses a convention that instructions in the delay slot
	27	* of a transfer-control instruction are indented by an extra space, thus:
	28	*
	29	* jmp @k0 ! control-transfer instruction
	30	* ldc k1, ssr ! delay slot
	31	*
	32	* Stack layout in 'ret_from_syscall':
	33	* ptrace needs to have all regs on the stack.
	34	* if the order here is changed, it needs to be
	35	* updated in ptrace.c and ptrace.h
	36	*
	37	* r0
	38	* ...
	39	* r15 = stack pointer
	40	* spc
	41	* pr
	42	* ssr
	43	* gbr
	44	* mach
	45	* macl
	46	* syscall #
	47	*
	48	*/
	49
	50	#if defined(CONFIG_PREEMPT)
	51	# define preempt_stop() cli
	52	#else
	53	# define preempt_stop()
	54	# define resume_kernel __restore_all
	55	#endif
	56
	57	#if defined(CONFIG_SH_STANDARD_BIOS) \|\| defined(CONFIG_SH_KGDB)
	58	! Handle kernel debug if either kgdb (SW) or gdb-stub (FW) is present.
	59	! If both are configured, handle the debug traps (breakpoints) in SW,
	60	! but still allow BIOS traps to FW.
	61
	62	.align 2
	63	debug_kernel:
	64	#if defined(CONFIG_SH_STANDARD_BIOS) && defined(CONFIG_SH_KGDB)
	65	/* Force BIOS call to FW (debug_trap put TRA in r8) */
	66	mov r8,r0
	67	shlr2 r0
	68	cmp/eq #0x3f,r0
	69	bt debug_kernel_fw
	70	#endif /* CONFIG_SH_STANDARD_BIOS && CONFIG_SH_KGDB */
	71
	72	debug_enter:
	73	#if defined(CONFIG_SH_KGDB)
	74	/* Jump to kgdb, pass stacked regs as arg */
	75	debug_kernel_sw:
	76	mov.l 3f, r0
	77	jmp @r0
	78	mov r15, r4
	79	.align 2
	80	3: .long kgdb_handle_exception
	81	#endif /* CONFIG_SH_KGDB */
	82
	83	#endif /* CONFIG_SH_STANDARD_BIOS \|\| CONFIG_SH_KGDB */
	84
	85
	86	.align 2
	87	debug_trap:
	88	#if defined(CONFIG_SH_STANDARD_BIOS) \|\| defined(CONFIG_SH_KGDB)
	89	mov #OFF_SR, r0
	90	mov.l @(r0,r15), r0 ! get status register
	91	shll r0
	92	shll r0 ! kernel space?
	93	bt/s debug_kernel
	94	#endif
	95	mov.l @r15, r0 ! Restore R0 value
	96	mov.l 1f, r8
	97	jmp @r8
	98	nop
	99
	100	.align 2
	101	ENTRY(exception_error)
	102	!
	103	#ifdef CONFIG_TRACE_IRQFLAGS
	104	mov.l 3f, r0
	105	jsr @r0
	106	nop
	107	#endif
	108	sti
	109	mov.l 2f, r0
	110	jmp @r0
	111	nop
	112
	113	!
	114	.align 2
	115	1: .long break_point_trap_software
	116	2: .long do_exception_error
	117	#ifdef CONFIG_TRACE_IRQFLAGS
	118	3: .long trace_hardirqs_on
	119	#endif
	120
	121	.align 2
	122	ret_from_exception:
	123	preempt_stop()
	124	#ifdef CONFIG_TRACE_IRQFLAGS
	125	mov.l 4f, r0
	126	jsr @r0
	127	nop
	128	#endif
	129	ENTRY(ret_from_irq)
	130	!
	131	mov #OFF_SR, r0
	132	mov.l @(r0,r15), r0 ! get status register
	133	shll r0
	134	shll r0 ! kernel space?
	135	get_current_thread_info r8, r0
	136	bt resume_kernel ! Yes, it's from kernel, go back soon
	137
	138	#ifdef CONFIG_PREEMPT
	139	bra resume_userspace
	140	nop
	141	ENTRY(resume_kernel)
	142	mov.l @(TI_PRE_COUNT,r8), r0 ! current_thread_info->preempt_count
	143	tst r0, r0
	144	bf noresched
	145	need_resched:
	146	mov.l @(TI_FLAGS,r8), r0 ! current_thread_info->flags
	147	tst #_TIF_NEED_RESCHED, r0 ! need_resched set?
	148	bt noresched
	149
	150	mov #OFF_SR, r0
	151	mov.l @(r0,r15), r0 ! get status register
	152	and #0xf0, r0 ! interrupts off (exception path)?
	153	cmp/eq #0xf0, r0
	154	bt noresched
	155
	156	mov.l 1f, r0
	157	mov.l r0, @(TI_PRE_COUNT,r8)
	158
	159	#ifdef CONFIG_TRACE_IRQFLAGS
	160	mov.l 3f, r0
	161	jsr @r0
	162	nop
	163	#endif
	164	sti
	165	mov.l 2f, r0
	166	jsr @r0
	167	nop
	168	mov #0, r0
	169	mov.l r0, @(TI_PRE_COUNT,r8)
	170	cli
	171	#ifdef CONFIG_TRACE_IRQFLAGS
	172	mov.l 4f, r0
	173	jsr @r0
	174	nop
	175	#endif
	176
	177	bra need_resched
	178	nop
	179
	180	noresched:
	181	bra __restore_all
	182	nop
	183
	184	.align 2
	185	1: .long PREEMPT_ACTIVE
	186	2: .long schedule
	187	#ifdef CONFIG_TRACE_IRQFLAGS
	188	3: .long trace_hardirqs_on
	189	4: .long trace_hardirqs_off
	190	#endif
	191	#endif
	192
	193	ENTRY(resume_userspace)
	194	! r8: current_thread_info
	195	cli
	196	#ifdef CONFIG_TRACE_IRQFLAGS
	197	mov.l 5f, r0
	198	jsr @r0
	199	nop
	200	#endif
	201	mov.l @(TI_FLAGS,r8), r0 ! current_thread_info->flags
	202	tst #_TIF_WORK_MASK, r0
	203	bt/s __restore_all
	204	tst #_TIF_NEED_RESCHED, r0
	205
	206	.align 2
	207	work_pending:
	208	! r0: current_thread_info->flags
	209	! r8: current_thread_info
	210	! t: result of "tst #_TIF_NEED_RESCHED, r0"
	211	bf/s work_resched
	212	tst #(_TIF_SIGPENDING \| _TIF_RESTORE_SIGMASK), r0
	213	work_notifysig:
	214	bt/s __restore_all
	215	mov r15, r4
	216	mov r12, r5 ! set arg1(save_r0)
	217	mov r0, r6
	218	mov.l 2f, r1
	219	mov.l 3f, r0
	220	jmp @r1
	221	lds r0, pr
	222	work_resched:
	223	#ifndef CONFIG_PREEMPT
	224	! gUSA handling
	225	mov.l @(OFF_SP,r15), r0 ! get user space stack pointer
	226	mov r0, r1
	227	shll r0
	228	bf/s 1f
	229	shll r0
	230	bf/s 1f
	231	mov #OFF_PC, r0
	232	! SP >= 0xc0000000 : gUSA mark
	233	mov.l @(r0,r15), r2 ! get user space PC (program counter)
	234	mov.l @(OFF_R0,r15), r3 ! end point
	235	cmp/hs r3, r2 ! r2 >= r3?
	236	bt 1f
	237	add r3, r1 ! rewind point #2
	238	mov.l r1, @(r0,r15) ! reset PC to rewind point #2
	239	!
	240	1:
	241	#endif
	242	mov.l 1f, r1
	243	jsr @r1 ! schedule
	244	nop
	245	cli
	246	#ifdef CONFIG_TRACE_IRQFLAGS
	247	mov.l 5f, r0
	248	jsr @r0
	249	nop
	250	#endif
	251	!
	252	mov.l @(TI_FLAGS,r8), r0 ! current_thread_info->flags
	253	tst #_TIF_WORK_MASK, r0
	254	bt __restore_all
	255	bra work_pending
	256	tst #_TIF_NEED_RESCHED, r0
	257
	258	.align 2
	259	1: .long schedule
	260	2: .long do_notify_resume
	261	3: .long restore_all
	262	#ifdef CONFIG_TRACE_IRQFLAGS
	263	4: .long trace_hardirqs_on
	264	5: .long trace_hardirqs_off
	265	#endif
	266
	267	.align 2
	268	syscall_exit_work:
	269	! r0: current_thread_info->flags
	270	! r8: current_thread_info
	271	tst #_TIF_SYSCALL_TRACE, r0
	272	bt/s work_pending
	273	tst #_TIF_NEED_RESCHED, r0
	274	#ifdef CONFIG_TRACE_IRQFLAGS
	275	mov.l 5f, r0
	276	jsr @r0
	277	nop
	278	#endif
	279	sti
	280	! XXX setup arguments...
	281	mov.l 4f, r0 ! do_syscall_trace
	282	jsr @r0
	283	nop
	284	bra resume_userspace
	285	nop
	286
	287	.align 2
	288	syscall_trace_entry:
	289	! Yes it is traced.
	290	! XXX setup arguments...
	291	mov.l 4f, r11 ! Call do_syscall_trace which notifies
	292	jsr @r11 ! superior (will chomp R[0-7])
	293	nop
	294	! Reload R0-R4 from kernel stack, where the
	295	! parent may have modified them using
	296	! ptrace(POKEUSR). (Note that R0-R2 are
	297	! used by the system call handler directly
	298	! from the kernel stack anyway, so don't need
	299	! to be reloaded here.) This allows the parent
	300	! to rewrite system calls and args on the fly.
	301	mov.l @(OFF_R4,r15), r4 ! arg0
	302	mov.l @(OFF_R5,r15), r5
	303	mov.l @(OFF_R6,r15), r6
	304	mov.l @(OFF_R7,r15), r7 ! arg3
	305	mov.l @(OFF_R3,r15), r3 ! syscall_nr
	306	!
	307	mov.l 2f, r10 ! Number of syscalls
	308	cmp/hs r10, r3
	309	bf syscall_call
	310	mov #-ENOSYS, r0
	311	bra syscall_exit
	312	mov.l r0, @(OFF_R0,r15) ! Return value
	313
	314	__restore_all:
	315	mov.l 1f, r0
	316	jmp @r0
	317	nop
	318
	319	.align 2
	320	1: .long restore_all
	321
	322	.align 2
	323	not_syscall_tra:
	324	bra debug_trap
	325	nop
	326
	327	.align 2
	328	syscall_badsys: ! Bad syscall number
	329	mov #-ENOSYS, r0
	330	bra resume_userspace
	331	mov.l r0, @(OFF_R0,r15) ! Return value
	332
	333
	334	/*
	335	* Syscall interface:
	336	*
	337	* Syscall #: R3
	338	* Arguments #0 to #3: R4--R7
	339	* Arguments #4 to #6: R0, R1, R2
	340	* TRA: (number of arguments + 0x10) x 4
	341	*
	342	* This code also handles delegating other traps to the BIOS/gdb stub
	343	* according to:
	344	*
	345	* Trap number
	346	* (TRA>>2) Purpose
	347	* -------- -------
	348	* 0x0-0xf old syscall ABI
	349	* 0x10-0x1f new syscall ABI
	350	* 0x20-0xff delegated through debug_trap to BIOS/gdb stub.
	351	*
	352	* Note: When we're first called, the TRA value must be shifted
	353	* right 2 bits in order to get the value that was used as the "trapa"
	354	* argument.
	355	*/
	356
	357	.align 2
	358	.globl ret_from_fork
	359	ret_from_fork:
	360	mov.l 1f, r8
	361	jsr @r8
	362	mov r0, r4
	363	bra syscall_exit
	364	nop
	365	.align 2
	366	1: .long schedule_tail
	367	!
	368	ENTRY(system_call)
	369	#if !defined(CONFIG_CPU_SH2)
	370	mov.l 1f, r9
	371	mov.l @r9, r8 ! Read from TRA (Trap Address) Register
	372	#endif
	373	!
	374	! Is the trap argument >= 0x20? (TRA will be >= 0x80)
	375	mov #0x7f, r9
	376	cmp/hi r9, r8
	377	bt/s not_syscall_tra
	378	mov #OFF_TRA, r9
	379	add r15, r9
	380	mov.l r8, @r9 ! set TRA value to tra
	381	#ifdef CONFIG_TRACE_IRQFLAGS
	382	mov.l 5f, r10
	383	jsr @r10
	384	nop
	385	#endif
	386	sti
	387
	388	!
	389	get_current_thread_info r8, r10
	390	mov.l @(TI_FLAGS,r8), r8
	391	mov #_TIF_SYSCALL_TRACE, r10
	392	tst r10, r8
	393	bf syscall_trace_entry
	394	!
	395	mov.l 2f, r8 ! Number of syscalls
	396	cmp/hs r8, r3
	397	bt syscall_badsys
	398	!
	399	syscall_call:
	400	shll2 r3 ! x4
	401	mov.l 3f, r8 ! Load the address of sys_call_table
	402	add r8, r3
	403	mov.l @r3, r8
	404	jsr @r8 ! jump to specific syscall handler
	405	nop
	406	mov.l @(OFF_R0,r15), r12 ! save r0
	407	mov.l r0, @(OFF_R0,r15) ! save the return value
	408	!
	409	syscall_exit:
	410	cli
	411	#ifdef CONFIG_TRACE_IRQFLAGS
	412	mov.l 6f, r0
	413	jsr @r0
	414	nop
	415	#endif
	416	!
	417	get_current_thread_info r8, r0
	418	mov.l @(TI_FLAGS,r8), r0 ! current_thread_info->flags
	419	tst #_TIF_ALLWORK_MASK, r0
	420	bf syscall_exit_work
	421	bra __restore_all
	422	nop
	423	.align 2
	424	#if !defined(CONFIG_CPU_SH2)
	425	1: .long TRA
	426	#endif
	427	2: .long NR_syscalls
	428	3: .long sys_call_table
	429	4: .long do_syscall_trace
	430	#ifdef CONFIG_TRACE_IRQFLAGS
	431	5: .long trace_hardirqs_on
	432	6: .long trace_hardirqs_off
	433	#endif