===================================================================
RCS file: /cvs/funnyos/arch/testarm/boot/loader.S,v
retrieving revision 1.3
retrieving revision 1.5
diff -u -r1.3 -r1.5
--- funnyos/arch/testarm/boot/loader.S	2007/11/04 22:39:27	1.3
+++ funnyos/arch/testarm/boot/loader.S	2007/11/23 13:37:42	1.5
@@ -1,5 +1,5 @@
 /*
- * $Id: loader.S,v 1.3 2007/11/04 22:39:27 init Exp $
+ * $Id: loader.S,v 1.5 2007/11/23 13:37:42 nbrk Exp $
  */
 /*
  *	FunnyOS loader
@@ -61,13 +61,25 @@
 	nop
 
 _vector_irq:
+	/* decrement pc by one insn */
+	sub lr, lr, #4
 
-	bl irq_trampoline
+	/* store all system mode registers */
+	stmdb sp!, {r0-r12, lr}
 
-	mrs r0, spsr
-	msr cpsr, r0
+	/* store sys_mode's cpsr */
+//	mrs r1, spsr
+//	stmdb sp!, {r1}
 
-	subs pc, r14, #4
+	/* pass sp (which now contains struct pcb of interrupted task) to irq_trampoline */
+	mov r0, sp
+
+	bl irq_trampoline
+
+	/* load r0-r12 and pc from the stack */
+	/* note ^ that copies SPSR into CPSR */
+	/** here we may return to different task (if pcb was changed in the stack memory) **/
+	ldmia sp!, {r0-r12, pc}^
 
 _vector_fiq:
 	nop