Initial source

1 files changed, 48 insertions, 0 deletions

diff --git a/i386/i386at/interrupt.S b/i386/i386at/interrupt.S
new file mode 100644
index 0000000..25cd66e
--- /dev/null
+++ b/i386/i386at/interrupt.S
@@ -0,0 +1,48 @@
+/* 
+ * Copyright (c) 1995 Shantanu Goel
+ * All Rights Reserved.
+ * 
+ * Permission to use, copy, modify and distribute this software and its
+ * documentation is hereby granted, provided that both the copyright
+ * notice and this permission notice appear in all copies of the
+ * software, derivative works or modified versions, and any portions
+ * thereof, and that both notices appear in supporting documentation.
+ * 
+ * THE AUTHOR ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
+ * CONDITION.  THE AUTHOR DISCLAIMS ANY LIABILITY OF ANY KIND FOR
+ * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
+ */
+
+#include <mach/machine/asm.h>
+
+#include "ipl.h"
+#include "pic.h"
+#include "i386asm.h"
+
+#define READ_ISR	(OCW_TEMPLATE|READ_NEXT_RD|READ_IS_ONRD)
+
+/*
+ * Generic interrupt handler.
+ *
+ * On entry, %eax contains the irq number.
+ */
+ENTRY(interrupt)
+	movl	%eax,%ecx		/* save irq number */
+	movb	$(NON_SPEC_EOI),%al	/* non-specific EOI */
+	outb	%al,$(PIC_MASTER_ICW)	/* ack interrupt to master */
+	cmpl	$8,%ecx			/* do we need to ack slave? */
+	jl	1f			/* no, skip it */
+	outb	%al,$(PIC_SLAVE_ICW)
+1:
+	shll	$2,%ecx			/* irq * 4 */
+	movl	EXT(intpri)(%ecx),%edx	/* get new ipl */
+	call	spl			/* set ipl */
+	movl	EXT(iunit)(%ecx),%edx	/* get device unit number */
+	pushl	%eax			/* push previous ipl */
+	pushl	%edx			/* push unit number */
+	call	*EXT(ivect)(%ecx)	/* call interrupt handler */
+	addl	$4,%esp			/* pop unit number */
+	call	splx_cli		/* restore previous ipl */
+	cli				/* XXX no more nested interrupts */
+	addl	$4,%esp			/* pop previous ipl */
+	ret				/* return */