x86, setup: "glove box" BIOS interrupts in the video code (cf06de7b) · Commits · e / devices / android_kernel_oneplus_sm8150

arch/x86/boot/video-bios.c

+13 −14

Original line number	Original line	Diff line number	Diff line
	@@ -2,6 +2,7 @@
	*		*
	* Copyright (C) 1991, 1992 Linus Torvalds		* Copyright (C) 1991, 1992 Linus Torvalds
	* Copyright 2007 rPath, Inc. - All Rights Reserved		* 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		* This file is part of the Linux kernel, and is made available under
	* the terms of the GNU General Public License version 2.		* the terms of the GNU General Public License version 2.
	@@ -29,21 +30,21 @@ static int bios_set_mode(struct mode_info *mi)

	static int set_bios_mode(u8 mode)		static int set_bios_mode(u8 mode)
	{		{
	u16 ax;		struct biosregs ireg, oreg;
	u8 new_mode;		u8 new_mode;

	ax = mode; /* AH=0x00 Set Video Mode */		initregs(&ireg);
	asm volatile(INT10		ireg.al = mode; /* AH=0x00 Set Video Mode */
	: "+a" (ax)		intcall(0x10, &ireg, NULL);
	: : "ebx", "ecx", "edx", "esi", "edi");

	ax = 0x0f00; /* Get Current Video Mode */
	asm volatile(INT10		ireg.ah = 0x0f; /* Get Current Video Mode */
	: "+a" (ax)		intcall(0x10, &ireg, &oreg);
	: : "ebx", "ecx", "edx", "esi", "edi");

	do_restore = 1; /* Assume video contents were lost */		do_restore = 1; /* Assume video contents were lost */
	new_mode = ax & 0x7f; /* Not all BIOSes are clean with the top bit */
			/* Not all BIOSes are clean with the top bit */
			new_mode = ireg.al & 0x7f;

	if (new_mode == mode)		if (new_mode == mode)
	return 0; /* Mode change OK */		return 0; /* Mode change OK */
	@@ -53,10 +54,8 @@ static int set_bios_mode(u8 mode)
	/* Mode setting failed, but we didn't end up where we		/* Mode setting failed, but we didn't end up where we
	started. That's bad. Try to revert to the original		started. That's bad. Try to revert to the original
	video mode. */		video mode. */
	ax = boot_params.screen_info.orig_video_mode;		ireg.ax = boot_params.screen_info.orig_video_mode;
	asm volatile(INT10		intcall(0x10, &ireg, NULL);
	: "+a" (ax)
	: : "ebx", "ecx", "edx", "esi", "edi");
	}		}
	#endif		#endif
	return -1;		return -1;

arch/x86/boot/video-vesa.c

+60 −77

Original line number	Original line	Diff line number	Diff line
	@@ -2,6 +2,7 @@
	*		*
	* Copyright (C) 1991, 1992 Linus Torvalds		* Copyright (C) 1991, 1992 Linus Torvalds
	* Copyright 2007 rPath, Inc. - All Rights Reserved		* 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		* This file is part of the Linux kernel, and is made available under
	* the terms of the GNU General Public License version 2.		* the terms of the GNU General Public License version 2.
	@@ -31,7 +32,7 @@ static inline void vesa_store_mode_params_graphics(void) {}
	static int vesa_probe(void)		static int vesa_probe(void)
	{		{
	#if defined(CONFIG_VIDEO_VESA) \|\| defined(CONFIG_FIRMWARE_EDID)		#if defined(CONFIG_VIDEO_VESA) \|\| defined(CONFIG_FIRMWARE_EDID)
	u16 ax, cx, di;		struct biosregs ireg, oreg;
	u16 mode;		u16 mode;
	addr_t mode_ptr;		addr_t mode_ptr;
	struct mode_info *mi;		struct mode_info *mi;
	@@ -39,13 +40,12 @@ static int vesa_probe(void)

	video_vesa.modes = GET_HEAP(struct mode_info, 0);		video_vesa.modes = GET_HEAP(struct mode_info, 0);

	ax = 0x4f00;		initregs(&ireg);
	di = (size_t)&vginfo;		ireg.ax = 0x4f00;
	asm(INT10		ireg.di = (size_t)&vginfo;
	: "+a" (ax), "+D" (di), "=m" (vginfo)		intcall(0x10, &ireg, &oreg);
	: : "ebx", "ecx", "edx", "esi");

	if (ax != 0x004f \|\|		if (ireg.ax != 0x004f \|\|
	vginfo.signature != VESA_MAGIC \|\|		vginfo.signature != VESA_MAGIC \|\|
	vginfo.version < 0x0102)		vginfo.version < 0x0102)
	return 0; /* Not present */		return 0; /* Not present */
	@@ -65,14 +65,12 @@ static int vesa_probe(void)

	memset(&vminfo, 0, sizeof vminfo); /* Just in case... */		memset(&vminfo, 0, sizeof vminfo); /* Just in case... */

	ax = 0x4f01;		ireg.ax = 0x4f01;
	cx = mode;		ireg.cx = mode;
	di = (size_t)&vminfo;		ireg.di = (size_t)&vminfo;
	asm(INT10		intcall(0x10, &ireg, &oreg);
	: "+a" (ax), "+c" (cx), "+D" (di), "=m" (vminfo)
	: : "ebx", "edx", "esi");

	if (ax != 0x004f)		if (ireg.ax != 0x004f)
	continue;		continue;

	if ((vminfo.mode_attr & 0x15) == 0x05) {		if ((vminfo.mode_attr & 0x15) == 0x05) {
	@@ -111,20 +109,19 @@ static int vesa_probe(void)

	static int vesa_set_mode(struct mode_info *mode)		static int vesa_set_mode(struct mode_info *mode)
	{		{
	u16 ax, bx, cx, di;		struct biosregs ireg, oreg;
	int is_graphic;		int is_graphic;
	u16 vesa_mode = mode->mode - VIDEO_FIRST_VESA;		u16 vesa_mode = mode->mode - VIDEO_FIRST_VESA;

	memset(&vminfo, 0, sizeof vminfo); /* Just in case... */		memset(&vminfo, 0, sizeof vminfo); /* Just in case... */

	ax = 0x4f01;		initregs(&ireg);
	cx = vesa_mode;		ireg.ax = 0x4f01;
	di = (size_t)&vminfo;		ireg.cx = vesa_mode;
	asm(INT10		ireg.di = (size_t)&vminfo;
	: "+a" (ax), "+c" (cx), "+D" (di), "=m" (vminfo)		intcall(0x10, &ireg, &oreg);
	: : "ebx", "edx", "esi");

	if (ax != 0x004f)		if (oreg.ax != 0x004f)
	return -1;		return -1;

	if ((vminfo.mode_attr & 0x15) == 0x05) {		if ((vminfo.mode_attr & 0x15) == 0x05) {
	@@ -141,14 +138,12 @@ static int vesa_set_mode(struct mode_info *mode)
	}		}


	ax = 0x4f02;		initregs(&ireg);
	bx = vesa_mode;		ireg.ax = 0x4f02;
	di = 0;		ireg.bx = vesa_mode;
	asm volatile(INT10		intcall(0x10, &ireg, &oreg);
	: "+a" (ax), "+b" (bx), "+D" (di)
	: : "ecx", "edx", "esi");

	if (ax != 0x004f)		if (oreg.ax != 0x004f)
	return -1;		return -1;

	graphic_mode = is_graphic;		graphic_mode = is_graphic;
	@@ -171,20 +166,17 @@ static int vesa_set_mode(struct mode_info *mode)
	/* Switch DAC to 8-bit mode */		/* Switch DAC to 8-bit mode */
	static void vesa_dac_set_8bits(void)		static void vesa_dac_set_8bits(void)
	{		{
			struct biosregs ireg, oreg;
	u8 dac_size = 6;		u8 dac_size = 6;

	/* If possible, switch the DAC to 8-bit mode */		/* If possible, switch the DAC to 8-bit mode */
	if (vginfo.capabilities & 1) {		if (vginfo.capabilities & 1) {
	u16 ax, bx;		initregs(&ireg);
			ireg.ax = 0x4f08;
	ax = 0x4f08;		ireg.bh = 0x08;
	bx = 0x0800;		intcall(0x10, &ireg, &oreg);
	asm volatile(INT10		if (oreg.ax == 0x004f)
	: "+a" (ax), "+b" (bx)		dac_size = oreg.bh;
	: : "ecx", "edx", "esi", "edi");

	if (ax == 0x004f)
	dac_size = bx >> 8;
	}		}

	/* Set the color sizes to the DAC size, and offsets to 0 */		/* Set the color sizes to the DAC size, and offsets to 0 */
	@@ -202,19 +194,17 @@ static void vesa_dac_set_8bits(void)
	/* Save the VESA protected mode info */		/* Save the VESA protected mode info */
	static void vesa_store_pm_info(void)		static void vesa_store_pm_info(void)
	{		{
	u16 ax, bx, di, es;		struct biosregs ireg, oreg;

	ax = 0x4f0a;		initregs(&ireg);
	bx = di = 0;		ireg.ax = 0x4f0a;
	asm("pushw %%es; "INT10"; movw %%es,%0; popw %%es"		intcall(0x10, &ireg, &oreg);
	: "=d" (es), "+a" (ax), "+b" (bx), "+D" (di)
	: : "ecx", "esi");

	if (ax != 0x004f)		if (oreg.ax != 0x004f)
	return;		return;

	boot_params.screen_info.vesapm_seg = es;		boot_params.screen_info.vesapm_seg = oreg.es;
	boot_params.screen_info.vesapm_off = di;		boot_params.screen_info.vesapm_off = oreg.di;
	}		}

	/*		/*
	@@ -252,7 +242,7 @@ static void vesa_store_mode_params_graphics(void)
	void vesa_store_edid(void)		void vesa_store_edid(void)
	{		{
	#ifdef CONFIG_FIRMWARE_EDID		#ifdef CONFIG_FIRMWARE_EDID
	u16 ax, bx, cx, dx, di;		struct biosregs ireg, oreg;

	/* Apparently used as a nonsense token... */		/* Apparently used as a nonsense token... */
	memset(&boot_params.edid_info, 0x13, sizeof boot_params.edid_info);		memset(&boot_params.edid_info, 0x13, sizeof boot_params.edid_info);
	@@ -260,33 +250,26 @@ void vesa_store_edid(void)
	if (vginfo.version < 0x0200)		if (vginfo.version < 0x0200)
	return; /* EDID requires VBE 2.0+ */		return; /* EDID requires VBE 2.0+ */

	ax = 0x4f15; /* VBE DDC */		initregs(&ireg);
	bx = 0x0000; /* Report DDC capabilities */		ireg.ax = 0x4f15; /* VBE DDC */
	cx = 0; /* Controller 0 */		/* ireg.bx = 0x0000; / / Report DDC capabilities */
	di = 0; /* ES:DI must be 0 by spec */		/* ireg.cx = 0; / / Controller 0 */
			ireg.es = 0; /* ES:DI must be 0 by spec */
	/* Note: The VBE DDC spec is different from the main VESA spec;		intcall(0x10, &ireg, &oreg);
	we genuinely have to assume all registers are destroyed here. */

	asm("pushw %%es; movw %2,%%es; "INT10"; popw %%es"
	: "+a" (ax), "+b" (bx), "+c" (cx), "+D" (di)
	: : "esi", "edx");

	if (ax != 0x004f)		if (oreg.ax != 0x004f)
	return; /* No EDID */		return; /* No EDID */

	/* BH = time in seconds to transfer EDD information */		/* BH = time in seconds to transfer EDD information */
	/* BL = DDC level supported */		/* BL = DDC level supported */

	ax = 0x4f15; /* VBE DDC */		ireg.ax = 0x4f15; /* VBE DDC */
	bx = 0x0001; /* Read EDID */		ireg.bx = 0x0001; /* Read EDID */
	cx = 0; /* Controller 0 */		/* ireg.cx = 0; / / Controller 0 */
	dx = 0; /* EDID block number */		/* ireg.dx = 0; / / EDID block number */
	di =(size_t) &boot_params.edid_info; /* (ES:)Pointer to block */		ireg.es = ds();
	asm(INT10		ireg.di =(size_t)&boot_params.edid_info; /* (ES:)Pointer to block */
	: "+a" (ax), "+b" (bx), "+d" (dx), "=m" (boot_params.edid_info),		intcall(0x10, &ireg, &oreg);
	"+c" (cx), "+D" (di)
	: : "esi");
	#endif /* CONFIG_FIRMWARE_EDID */		#endif /* CONFIG_FIRMWARE_EDID */
	}		}

arch/x86/boot/video-vga.c

+59 −36

Original line number	Original line	Diff line number	Diff line
	@@ -2,6 +2,7 @@
	*		*
	* Copyright (C) 1991, 1992 Linus Torvalds		* Copyright (C) 1991, 1992 Linus Torvalds
	* Copyright 2007 rPath, Inc. - All Rights Reserved		* 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		* This file is part of the Linux kernel, and is made available under
	* the terms of the GNU General Public License version 2.		* the terms of the GNU General Public License version 2.
	@@ -39,30 +40,30 @@ static __videocard video_vga;
	/* Set basic 80x25 mode */		/* Set basic 80x25 mode */
	static u8 vga_set_basic_mode(void)		static u8 vga_set_basic_mode(void)
	{		{
			struct biosregs ireg, oreg;
	u16 ax;		u16 ax;
	u8 rows;		u8 rows;
	u8 mode;		u8 mode;

			initregs(&ireg);

	#ifdef CONFIG_VIDEO_400_HACK		#ifdef CONFIG_VIDEO_400_HACK
	if (adapter >= ADAPTER_VGA) {		if (adapter >= ADAPTER_VGA) {
	asm volatile(INT10		ireg.ax = 0x1202;
	: : "a" (0x1202), "b" (0x0030)		ireg.bx = 0x0030;
	: "ecx", "edx", "esi", "edi");		intcall(0x10, &ireg, NULL);
	}		}
	#endif		#endif

	ax = 0x0f00;		ax = 0x0f00;
	asm volatile(INT10		intcall(0x10, &ireg, &oreg);
	: "+a" (ax)		mode = oreg.al;
	: : "ebx", "ecx", "edx", "esi", "edi");

	mode = (u8)ax;

	set_fs(0);		set_fs(0);
	rows = rdfs8(0x484); /* rows minus one */		rows = rdfs8(0x484); /* rows minus one */

	#ifndef CONFIG_VIDEO_400_HACK		#ifndef CONFIG_VIDEO_400_HACK
	if ((ax == 0x5003 \|\| ax == 0x5007) &&		if ((oreg.ax == 0x5003 \|\| oreg.ax == 0x5007) &&
	(rows == 0 \|\| rows == 24))		(rows == 0 \|\| rows == 24))
	return mode;		return mode;
	#endif		#endif
	@@ -71,10 +72,8 @@ static u8 vga_set_basic_mode(void)
	mode = 3;		mode = 3;

	/* Set the mode */		/* Set the mode */
	ax = mode;		ireg.ax = mode; /* AH=0: set mode */
	asm volatile(INT10		intcall(0x10, &ireg, NULL);
	: "+a" (ax)
	: : "ebx", "ecx", "edx", "esi", "edi");
	do_restore = 1;		do_restore = 1;
	return mode;		return mode;
	}		}
	@@ -82,43 +81,69 @@ static u8 vga_set_basic_mode(void)
	static void vga_set_8font(void)		static void vga_set_8font(void)
	{		{
	/* Set 8x8 font - 80x43 on EGA, 80x50 on VGA */		/* Set 8x8 font - 80x43 on EGA, 80x50 on VGA */
			struct biosregs ireg;

			initregs(&ireg);

	/* Set 8x8 font */		/* Set 8x8 font */
	asm volatile(INT10 : : "a" (0x1112), "b" (0));		ireg.ax = 0x1112;
			/* ireg.bl = 0; */
			intcall(0x10, &ireg, NULL);

	/* Use alternate print screen */		/* Use alternate print screen */
	asm volatile(INT10 : : "a" (0x1200), "b" (0x20));		ireg.ax = 0x1200;
			ireg.bl = 0x20;
			intcall(0x10, &ireg, NULL);

	/* Turn off cursor emulation */		/* Turn off cursor emulation */
	asm volatile(INT10 : : "a" (0x1201), "b" (0x34));		ireg.ax = 0x1201;
			ireg.bl = 0x34;
			intcall(0x10, &ireg, NULL);

	/* Cursor is scan lines 6-7 */		/* Cursor is scan lines 6-7 */
	asm volatile(INT10 : : "a" (0x0100), "c" (0x0607));		ireg.ax = 0x0100;
			ireg.cx = 0x0607;
			intcall(0x10, &ireg, NULL);
	}		}

	static void vga_set_14font(void)		static void vga_set_14font(void)
	{		{
	/* Set 9x14 font - 80x28 on VGA */		/* Set 9x14 font - 80x28 on VGA */
			struct biosregs ireg;

			initregs(&ireg);

	/* Set 9x14 font */		/* Set 9x14 font */
	asm volatile(INT10 : : "a" (0x1111), "b" (0));		ireg.ax = 0x1111;
			/* ireg.bl = 0; */
			intcall(0x10, &ireg, NULL);

	/* Turn off cursor emulation */		/* Turn off cursor emulation */
	asm volatile(INT10 : : "a" (0x1201), "b" (0x34));		ireg.ax = 0x1201;
			ireg.bl = 0x34;
			intcall(0x10, &ireg, NULL);

	/* Cursor is scan lines 11-12 */		/* Cursor is scan lines 11-12 */
	asm volatile(INT10 : : "a" (0x0100), "c" (0x0b0c));		ireg.ax = 0x0100;
			ireg.cx = 0x0b0c;
			intcall(0x10, &ireg, NULL);
	}		}

	static void vga_set_80x43(void)		static void vga_set_80x43(void)
	{		{
	/* Set 80x43 mode on VGA (not EGA) */		/* Set 80x43 mode on VGA (not EGA) */
			struct biosregs ireg;

			initregs(&ireg);

	/* Set 350 scans */		/* Set 350 scans */
	asm volatile(INT10 : : "a" (0x1201), "b" (0x30));		ireg.ax = 0x1201;
			ireg.bl = 0x30;
			intcall(0x10, &ireg, NULL);

	/* Reset video mode */		/* Reset video mode */
	asm volatile(INT10 : : "a" (0x0003));		ireg.ax = 0x0003;
			intcall(0x10, &ireg, NULL);

	vga_set_8font();		vga_set_8font();
	}		}
	@@ -225,8 +250,6 @@ static int vga_set_mode(struct mode_info *mode)
	*/		*/
	static int vga_probe(void)		static int vga_probe(void)
	{		{
	u16 ega_bx;

	static const char *card_name[] = {		static const char *card_name[] = {
	"CGA/MDA/HGC", "EGA", "VGA"		"CGA/MDA/HGC", "EGA", "VGA"
	};		};
	@@ -240,26 +263,26 @@ static int vga_probe(void)
	sizeof(ega_modes)/sizeof(struct mode_info),		sizeof(ega_modes)/sizeof(struct mode_info),
	sizeof(vga_modes)/sizeof(struct mode_info),		sizeof(vga_modes)/sizeof(struct mode_info),
	};		};
	u8 vga_flag;

	asm(INT10		struct biosregs ireg, oreg;
	: "=b" (ega_bx)
	: "a" (0x1200), "b" (0x10) /* Check EGA/VGA */		initregs(&ireg);
	: "ecx", "edx", "esi", "edi");
			ireg.ax = 0x1200;
			ireg.bl = 0x10; /* Check EGA/VGA */
			intcall(0x10, &ireg, &oreg);

	#ifndef _WAKEUP		#ifndef _WAKEUP
	boot_params.screen_info.orig_video_ega_bx = ega_bx;		boot_params.screen_info.orig_video_ega_bx = oreg.bx;
	#endif		#endif

	/* If we have MDA/CGA/HGC then BL will be unchanged at 0x10 */		/* If we have MDA/CGA/HGC then BL will be unchanged at 0x10 */
	if ((u8)ega_bx != 0x10) {		if (oreg.bl != 0x10) {
	/* EGA/VGA */		/* EGA/VGA */
	asm(INT10		ireg.ax = 0x1a00;
	: "=a" (vga_flag)		intcall(0x10, &ireg, &oreg);
	: "a" (0x1a00)
	: "ebx", "ecx", "edx", "esi", "edi");

	if (vga_flag == 0x1a) {		if (oreg.al == 0x1a) {
	adapter = ADAPTER_VGA;		adapter = ADAPTER_VGA;
	#ifndef _WAKEUP		#ifndef _WAKEUP
	boot_params.screen_info.orig_video_isVGA = 1;		boot_params.screen_info.orig_video_isVGA = 1;

arch/x86/boot/video.c

+19 −23

Original line number	Original line	Diff line number	Diff line
	@@ -2,6 +2,7 @@
	*		*
	* Copyright (C) 1991, 1992 Linus Torvalds		* Copyright (C) 1991, 1992 Linus Torvalds
	* Copyright 2007 rPath, Inc. - All Rights Reserved		* 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		* This file is part of the Linux kernel, and is made available under
	* the terms of the GNU General Public License version 2.		* the terms of the GNU General Public License version 2.
	@@ -18,33 +19,29 @@

	static void store_cursor_position(void)		static void store_cursor_position(void)
	{		{
	u16 curpos;		struct biosregs ireg, oreg;
	u16 ax, bx;

	ax = 0x0300;		initregs(&ireg);
	bx = 0;		ireg.ah = 0x03;
	asm(INT10		intcall(0x10, &ireg, &oreg);
	: "=d" (curpos), "+a" (ax), "+b" (bx)
	: : "ecx", "esi", "edi");

	boot_params.screen_info.orig_x = curpos;		boot_params.screen_info.orig_x = oreg.dl;
	boot_params.screen_info.orig_y = curpos >> 8;		boot_params.screen_info.orig_y = oreg.dh;
	}		}

	static void store_video_mode(void)		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,		/* N.B.: the saving of the video page here is a bit silly,
	since we pretty much assume page 0 everywhere. */		since we pretty much assume page 0 everywhere. */
	ax = 0x0f00;		initregs(&ireg);
	asm(INT10		ireg.ah = 0x0f;
	: "+a" (ax), "=b" (page)		intcall(0x10, &ireg, &oreg);
	: : "ecx", "edx", "esi", "edi");

	/* Not all BIOSes are clean with respect to the top bit */		/* 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_mode = oreg.al & 0x7f;
	boot_params.screen_info.orig_video_page = page >> 8;		boot_params.screen_info.orig_video_page = oreg.bh;
	}		}

	/*		/*
	@@ -257,7 +254,7 @@ static void restore_screen(void)
	int y;		int y;
	addr_t dst = 0;		addr_t dst = 0;
	u16 *src = saved.data;		u16 *src = saved.data;
	u16 ax, bx, dx;		struct biosregs ireg;

	if (graphic_mode)		if (graphic_mode)
	return; /* Can't restore onto a graphic mode */		return; /* Can't restore onto a graphic mode */
	@@ -296,12 +293,11 @@ static void restore_screen(void)
	}		}

	/* Restore cursor position */		/* Restore cursor position */
	ax = 0x0200; /* Set cursor position */		initregs(&ireg);
	bx = 0; /* Page number (<< 8) */		ireg.ah = 0x02; /* Set cursor position */
	dx = (saved.cury << 8)+saved.curx;		ireg.dh = saved.cury;
	asm volatile(INT10		ireg.dl = saved.curx;
	: "+a" (ax), "+b" (bx), "+d" (dx)		intcall(0x10, &ireg, NULL);
	: : "ecx", "esi", "edi");
	}		}
	#else		#else
	#define save_screen() ((void)0)		#define save_screen() ((void)0)

arch/x86/boot/video.h

+0 −14

Original line number	Original line	Diff line number	Diff line
	@@ -112,20 +112,6 @@ extern int force_x, force_y; /* Don't query the BIOS for cols/rows */
	extern int do_restore; /* Restore screen contents */		extern int do_restore; /* Restore screen contents */
	extern int graphic_mode; /* Graphics mode with linear frame buffer */		extern int graphic_mode; /* Graphics mode with linear frame buffer */

	/*
	* int $0x10 is notorious for touching registers it shouldn't.
	* gcc doesn't like %ebp being clobbered, so define it as a push/pop
	* sequence here.
	*
	* A number of systems, including the original PC can clobber %bp in
	* certain circumstances, like when scrolling. There exists at least
	* one Trident video card which could clobber DS under a set of
	* circumstances that we are unlikely to encounter (scrolling when
	* using an extended graphics mode of more than 800x600 pixels), but
	* it's cheap insurance to deal with that here.
	*/
	#define INT10 "pushl %%ebp; pushw %%ds; int $0x10; popw %%ds; popl %%ebp"

	/* Accessing VGA indexed registers */		/* Accessing VGA indexed registers */
	static inline u8 in_idx(u16 port, u8 index)		static inline u8 in_idx(u16 port, u8 index)
	{		{