add hercules support.

stage2/hercules.h

@@ -0,0 +1,38 @@
+/* hercules.h - hercules console interface */
+/*
+ *  GRUB  --  GRand Unified Bootloader
+ *  Copyright (C) 2001  Free Software Foundation, Inc.
+ *
+ *  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; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  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.
+ */
+
+#ifndef GRUB_HERCULES_HEADER
+#define GRUB_HERCULES_HEADER	1
+
+/* Macros.  */
+#define HERCULES_VIDEO_ADDR	RAW_ADDR (0xB0000)
+#define HERCULES_WIDTH		80
+#define HERCULES_HEIGHT		25
+#define HERCULES_INDEX_REG	0x3b4
+#define HERCULES_DATA_REG	0x3b5
+
+/* Functions.  */
+void herc_putchar (int c);
+void herc_cls (void);
+int herc_getxy (void);
+void herc_gotoxy (int x, int y);
+void herc_set_attrib (int attr);
+
+#endif /* ! GRUB_HERCULES_HEADER */