1 files changed, 51 insertions, 0 deletions
diff --git a/purgatory/arch/i386/pic.c b/purgatory/arch/i386/pic.c
new file mode 100644
index 0000000..c23c459
--- /dev/null
+++ b/purgatory/arch/i386/pic.c
@@ -0,0 +1,51 @@
+/*
+ * kexec: Linux boots Linux
+ *
+ * Copyright (C) 2003,2004  Eric Biederman (ebiederm@xmission.com)
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation (version 2 of the License).
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+#include <sys/io.h>
+#include <purgatory.h>
+#include "purgatory-x86.h"
+
+
+void x86_setup_legacy_pic(void)
+{
+	/* Load the legacy dos settings into the 8259A pic */
+	outb(0xff, 0x21);	/* mask all of 8259A-1 */
+	outb(0xff, 0xa1);	/* mask all of 8259A-2 */
+
+	outb(0x11, 0x20);	/* ICW1: select 8259A-1 init */
+	outb(0x11, 0x80);	/* A short delay */
+
+	outb(0x08, 0x21);	/* ICW2: 8259A-1 IR0-7 mappend to 0x8-0xf */
+	outb(0x08, 0x80);	/* A short delay */
+
+	outb(0x01, 0x21);	/* Normal 8086 auto EOI mode */
+	outb(0x01, 0x80);	/* A short delay */
+
+	outb(0x11, 0xa0);	/* ICW1: select 8259A-2 init */
+	outb(0x11, 0x80);	/* A short delay */
+
+	outb(0x70, 0xa1);	/* ICW2: 8259A-2 IR0-7 mappend to 0x70-0x77 */
+	outb(0x70, 0x80);	/* A short delay */
+
+	outb(0x01, 0xa1);	/* Normal 8086 auto EOI mode */
+	outb(0x01, 0x80);	/* A short delay */
+
+	outb(0x00, 0x21);	/* Unmask all of 8259A-1 */
+	outb(0x00, 0xa1);	/* Unmask all of 8259A-2 */
+}
+