patch-2.0.21-2.1.0 linux/arch/m68k/ifpsp060/iskeleton.S

• Lines: 123
• Date: Wed Sep 25 10:47:39 1996
• Orig file: lx2.0/v2.0.21/linux/arch/m68k/ifpsp060/iskeleton.S
• Orig date: Fri Apr 26 12:12:35 1996

diff -u --recursive --new-file lx2.0/v2.0.21/linux/arch/m68k/ifpsp060/iskeleton.S linux/arch/m68k/ifpsp060/iskeleton.S
@@ -34,6 +34,15 @@
 |	(3) example "Call-out" table
 |
 
+#include <linux/linkage.h>
+
+LOFF_ORIG_D0	= 0x20
+
+#define SAVE_ALL				\
+	clrl	%sp@-;     /* stk_adj */	\
+	movel	%d0,%sp@-; /* orig d0 */	\
+	movel	%d0,%sp@-; /* d0 */		\
+	moveml	%d1-%d5/%a0-%a1,%sp@-
 
 |################################
 | (1) EXAMPLE CALL-OUTS 	#
@@ -61,9 +70,22 @@
 | To simply continue execution at the next instruction, just
 | do an "rte".
 |
+| Linux/68k: If returning to user space, check for needed reselections.
+
 	.global		_060_isp_done
 _060_isp_done:
+	btst	#0x5,%sp@		| supervisor bit set in saved SR?
+	beq	Lnotkern
 	rte
+Lnotkern:
+	tstl	SYMBOL_NAME(need_resched)
+	bne	Lmustsched
+	rte
+Lmustsched:
+	SAVE_ALL
+	moveq	#-1,%d0
+	movel	%d0,%sp@(LOFF_ORIG_D0)    | indicate stack frame not for syscall
+	bral	SYMBOL_NAME(ret_from_exception)	| deliver signals, reschedule etc..
 
 |
 | _060_real_chk():
@@ -71,13 +93,15 @@
 | This is an alternate exit point for the Unimplemented Integer
 | Instruction exception handler. If the instruction was a "chk2"
 | and the operand was out of bounds, then _isp_unimp() creates
-| a CHK exception stack frame from the Unimplemented Integer Instruction
+| a CHK exception stack frame from the Unimplemented Integer Instrcution
 | stack frame and branches to this routine.
 |
+| Linux/68k: commented out test for tracing
+
 	.global		_060_real_chk
 _060_real_chk:
-	tst.b		(%sp)			| is tracing enabled?
-	bpls		real_chk_end		| no
+|	tst.b		(%sp)			| is tracing enabled?
+|	bpls		real_chk_end		| no
 
 |
 |	    CHK FRAME		   TRACE FRAME
@@ -92,11 +116,11 @@
 |	*      SR	*	*      SR	*
 |	*****************	*****************
 |
-	move.b		#0x24,0x7(%sp)		| set trace vecno
-	bral		_060_real_trace
+|	move.b		#0x24,0x7(%sp)		| set trace vecno
+|	bral		_060_real_trace
 
 real_chk_end:
-	rte
+	bral		SYMBOL_NAME(trap)	| jump to trap handler
 
 |
 | _060_real_divbyzero:
@@ -112,10 +136,12 @@
 | then it create a Trace exception stack frame from the "chk" exception
 | stack frame and branches to the _real_trace() entry point.
 | 
+| Linux/68k: commented out test for tracing
+
 	.global		_060_real_divbyzero
 _060_real_divbyzero:
-	tst.b		(%sp)			| is tracing enabled?
-	bpls		real_divbyzero_end	| no
+|	tst.b		(%sp)			| is tracing enabled?
+|	bpls		real_divbyzero_end	| no
 
 |
 |	 DIVBYZERO FRAME	   TRACE FRAME
@@ -130,11 +156,11 @@
 |	*      SR	*	*      SR	*
 |	*****************	*****************
 |
-	move.b		#0x24,0x7(%sp)		| set trace vecno
-	bral		_060_real_trace
+|	move.b		#0x24,0x7(%sp)		| set trace vecno
+|	bral		_060_real_trace
 
 real_divbyzero_end:
-	rte
+	bral		SYMBOL_NAME(trap)	| jump to trap handler
 
 |##########################
 
@@ -177,6 +203,9 @@
 | Expected outputs:
 |	d0 = 0 -> success; non-zero -> failure
 |
+| Linux/68k: As long as ints are disabled, no swapping out should
+| occur (hopefully...)
+|
 	.global		_060_real_lock_page
 _060_real_lock_page:
 	clr.l		%d0
@@ -194,6 +223,9 @@
 |	d0 = `xxxxxxff -> supervisor; `xxxxxx00 -> user
 |	d1 = `xxxxxxff -> longword; `xxxxxx00 -> word
 |
+| Linux/68k: As we do no special locking operation, also no unlocking
+| is needed...
+
 	.global		_060_real_unlock_page
 _060_real_unlock_page:
 	clr.l		%d0