x86, setup: "glove box" BIOS interrupts in the video code
Impact: BIOS proofing
"Glove box" off BIOS interrupts in the video code.
LKML-Reference: <49DE7F79.4030106@zytor.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
diff --git a/arch/x86/boot/video.c b/arch/x86/boot/video.c
index 3bef2c1..bad728b 100644
--- a/arch/x86/boot/video.c
+++ b/arch/x86/boot/video.c
@@ -2,6 +2,7 @@
*
* Copyright (C) 1991, 1992 Linus Torvalds
* Copyright 2007 rPath, Inc. - All Rights Reserved
+ * Copyright 2009 Intel Corporation; author H. Peter Anvin
*
* This file is part of the Linux kernel, and is made available under
* the terms of the GNU General Public License version 2.
@@ -18,33 +19,29 @@
static void store_cursor_position(void)
{
- u16 curpos;
- u16 ax, bx;
+ struct biosregs ireg, oreg;
- ax = 0x0300;
- bx = 0;
- asm(INT10
- : "=d" (curpos), "+a" (ax), "+b" (bx)
- : : "ecx", "esi", "edi");
+ initregs(&ireg);
+ ireg.ah = 0x03;
+ intcall(0x10, &ireg, &oreg);
- boot_params.screen_info.orig_x = curpos;
- boot_params.screen_info.orig_y = curpos >> 8;
+ boot_params.screen_info.orig_x = oreg.dl;
+ boot_params.screen_info.orig_y = oreg.dh;
}
static void store_video_mode(void)
{
- u16 ax, page;
+ struct biosregs ireg, oreg;
/* N.B.: the saving of the video page here is a bit silly,
since we pretty much assume page 0 everywhere. */
- ax = 0x0f00;
- asm(INT10
- : "+a" (ax), "=b" (page)
- : : "ecx", "edx", "esi", "edi");
+ initregs(&ireg);
+ ireg.ah = 0x0f;
+ intcall(0x10, &ireg, &oreg);
/* Not all BIOSes are clean with respect to the top bit */
- boot_params.screen_info.orig_video_mode = ax & 0x7f;
- boot_params.screen_info.orig_video_page = page >> 8;
+ boot_params.screen_info.orig_video_mode = oreg.al & 0x7f;
+ boot_params.screen_info.orig_video_page = oreg.bh;
}
/*
@@ -257,7 +254,7 @@
int y;
addr_t dst = 0;
u16 *src = saved.data;
- u16 ax, bx, dx;
+ struct biosregs ireg;
if (graphic_mode)
return; /* Can't restore onto a graphic mode */
@@ -296,12 +293,11 @@
}
/* Restore cursor position */
- ax = 0x0200; /* Set cursor position */
- bx = 0; /* Page number (<< 8) */
- dx = (saved.cury << 8)+saved.curx;
- asm volatile(INT10
- : "+a" (ax), "+b" (bx), "+d" (dx)
- : : "ecx", "esi", "edi");
+ initregs(&ireg);
+ ireg.ah = 0x02; /* Set cursor position */
+ ireg.dh = saved.cury;
+ ireg.dl = saved.curx;
+ intcall(0x10, &ireg, NULL);
}
#else
#define save_screen() ((void)0)