Add vga bios repost support. Fetched from the NetBSD tree mostly.

Tested on multiple i386 and it works, amd64 works also with a few
exceptions that will get fixed.

The initial effort of importing was done by oga@, thanks!

Lots of testing and debugging by mlarkin@ and me.
Okay deraadt@, oga@, mlarkin@.

1 files changed, 158 insertions, 0 deletions

diff --git a/sys/dev/x86emu/x86emu_util.c b/sys/dev/x86emu/x86emu_util.c
new file mode 100644
index 00000000000..f9d5761a46f
--- /dev/null
+++ b/sys/dev/x86emu/x86emu_util.c
@@ -0,0 +1,158 @@
+/*	$NetBSD: x86emu_util.c,v 1.2 2007/12/04 17:32:22 joerg Exp $	*/
+/* $OpenBSD */
+
+/****************************************************************************
+*
+*  Realmode X86 Emulator Library
+*
+*  Copyright (C) 1996-1999 SciTech Software, Inc.
+*  Copyright (C) David Mosberger-Tang
+*  Copyright (C) 1999 Egbert Eich
+*  Copyright (C) 2007 Joerg Sonnenberger
+*
+*  ========================================================================
+*
+*  Permission to use, copy, modify, distribute, and sell this software and
+*  its documentation for any purpose is hereby granted without fee,
+*  provided that the above copyright notice appear in all copies and that
+*  both that copyright notice and this permission notice appear in
+*  supporting documentation, and that the name of the authors not be used
+*  in advertising or publicity pertaining to distribution of the software
+*  without specific, written prior permission.  The authors makes no
+*  representations about the suitability of this software for any purpose.
+*  It is provided "as is" without express or implied warranty.
+*
+*  THE AUTHORS DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
+*  INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
+*  EVENT SHALL THE AUTHORS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
+*  CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF
+*  USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
+*  OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+*  PERFORMANCE OF THIS SOFTWARE.
+*
+****************************************************************************/
+
+#include <sys/param.h>
+#include <sys/endian.h>
+
+#include <lib/libkern/x86emu.h>
+#include <lib/libkern/x86emu_regs.h>
+
+
+/****************************************************************************
+PARAMETERS:
+addr	- Emulator memory address to read
+
+RETURNS:
+Byte value read from emulator memory.
+
+REMARKS:
+Reads a byte value from the emulator memory.
+****************************************************************************/
+static uint8_t
+rdb(struct X86EMU *emu, uint32_t addr)
+{
+	if (addr > emu->mem_size - 1)
+		X86EMU_halt_sys(emu);
+	return emu->mem_base[addr];
+}
+/****************************************************************************
+PARAMETERS:
+addr	- Emulator memory address to read
+
+RETURNS:
+Word value read from emulator memory.
+
+REMARKS:
+Reads a word value from the emulator memory.
+****************************************************************************/
+static uint16_t
+rdw(struct X86EMU *emu, uint32_t addr)
+{
+	if (addr > emu->mem_size - 2)
+		X86EMU_halt_sys(emu);
+	/* XXX alignment *sigh* */
+	return *(u_int16_t *)(emu->mem_base + addr);
+}
+/****************************************************************************
+PARAMETERS:
+addr	- Emulator memory address to read
+
+RETURNS:
+Long value read from emulator memory.
+REMARKS:
+Reads a long value from the emulator memory.
+****************************************************************************/
+static uint32_t
+rdl(struct X86EMU *emu, uint32_t addr)
+{
+	if (addr > emu->mem_size - 4)
+		X86EMU_halt_sys(emu);
+	/* XXX alignment *sigh* */
+	return *(u_int32_t *)(emu->mem_base + addr);
+}
+/****************************************************************************
+PARAMETERS:
+addr	- Emulator memory address to read
+val		- Value to store
+
+REMARKS:
+Writes a byte value to emulator memory.
+****************************************************************************/
+static void
+wrb(struct X86EMU *emu, uint32_t addr, uint8_t val)
+{
+	if (addr > emu->mem_size - 1)
+		X86EMU_halt_sys(emu);
+	emu->mem_base[addr] = val;
+}
+/****************************************************************************
+PARAMETERS:
+addr	- Emulator memory address to read
+val		- Value to store
+
+REMARKS:
+Writes a word value to emulator memory.
+****************************************************************************/
+static void
+wrw(struct X86EMU *emu, uint32_t addr, uint16_t val)
+{
+	if (addr > emu->mem_size - 2)
+		X86EMU_halt_sys(emu);
+	/* XXX alignment */
+	*((u_int16_t *)(emu->mem_base + addr)) = val;
+}
+/****************************************************************************
+PARAMETERS:
+addr	- Emulator memory address to read
+val		- Value to store
+
+REMARKS:
+Writes a long value to emulator memory.
+****************************************************************************/
+static void
+wrl(struct X86EMU *emu, uint32_t addr, uint32_t val)
+{
+	if (addr > emu->mem_size - 4)
+		X86EMU_halt_sys(emu);
+	/* XXX alignment *sigh* */
+	*((u_int32_t *)(emu->mem_base + addr)) = val;
+}
+
+/*----------------------------- Setup -------------------------------------*/
+
+void
+X86EMU_init_default(struct X86EMU *emu)
+{
+	int i;
+
+	emu->emu_rdb = rdb;
+	emu->emu_rdw = rdw;
+	emu->emu_rdl = rdl;
+	emu->emu_wrb = wrb;
+	emu->emu_wrw = wrw;
+	emu->emu_wrl = wrl;
+
+	for (i = 0; i < 256; i++)
+		emu->_X86EMU_intrTab[i] = NULL;
+}