arch/i386/boot/video-vesa.c - maze/linux - Git at Google

 /* -*- linux-c -*- ------------------------------------------------------- *
  *
  *   Copyright (C) 1991, 1992 Linus Torvalds
  *   Copyright 2007 rPath, Inc. - All Rights Reserved
  *
  *   This file is part of the Linux kernel, and is made available under
  *   the terms of the GNU General Public License version 2.
  *
  * ----------------------------------------------------------------------- */

 /*
  * arch/i386/boot/video-vesa.c
  *
  * VESA text modes
  */

 #include "boot.h"
 #include "video.h"
 #include "vesa.h"

 /* VESA information */
 static struct vesa_general_info vginfo;
 static struct vesa_mode_info vminfo;

 __videocard video_vesa;

 static void vesa_store_mode_params_graphics(void);

 static int vesa_probe(void)
 {
 #if defined(CONFIG_VIDEO_VESA) || defined(CONFIG_FIRMWARE_EDID)
 	u16 ax, cx, di;
 	u16 mode;
 	addr_t mode_ptr;
 	struct mode_info *mi;
 	int nmodes = 0;

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

 	vginfo.signature = VBE2_MAGIC;

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

 	if (ax != 0x004f ||
 	    vginfo.signature != VESA_MAGIC ||
 	    vginfo.version < 0x0102)
 		return 0;	/* Not present */
 #endif /* CONFIG_VIDEO_VESA || CONFIG_FIRMWARE_EDID */
 #ifdef CONFIG_VIDEO_VESA
 	set_fs(vginfo.video_mode_ptr.seg);
 	mode_ptr = vginfo.video_mode_ptr.off;

 	while ((mode = rdfs16(mode_ptr)) != 0xffff) {
 		mode_ptr += 2;

 		if (heap_free() < sizeof(struct mode_info))
 			break;	/* Heap full, can't save mode info */

 		if (mode & ~0x1ff)
 			continue;

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

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

 		if (ax != 0x004f)
 			continue;

 		if ((vminfo.mode_attr & 0x15) == 0x05) {
 			/* Text Mode, TTY BIOS supported,
 			   supported by hardware */
 			mi = GET_HEAP(struct mode_info, 1);
 			mi->mode = mode + VIDEO_FIRST_VESA;
 			mi->x    = vminfo.h_res;
 			mi->y    = vminfo.v_res;
 			nmodes++;
 		} else if ((vminfo.mode_attr & 0x99) == 0x99) {
 #ifdef CONFIG_FB
 			/* Graphics mode, color, linear frame buffer
 			   supported -- register the mode but hide from
 			   the menu.  Only do this if framebuffer is
 			   configured, however, otherwise the user will
 			   be left without a screen. */
 			mi = GET_HEAP(struct mode_info, 1);
 			mi->mode = mode + VIDEO_FIRST_VESA;
 			mi->x = mi->y = 0;
 			nmodes++;
 #endif
 		}
 	}

 	return nmodes;
 #else
 	return 0;
 #endif /* CONFIG_VIDEO_VESA */
 }

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

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

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

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

 	if ((vminfo.mode_attr & 0x15) == 0x05) {
 		/* It's a supported text mode */
 		is_graphic = 0;
 	} else if ((vminfo.mode_attr & 0x99) == 0x99) {
 		/* It's a graphics mode with linear frame buffer */
 		is_graphic = 1;
 		vesa_mode |= 0x4000; /* Request linear frame buffer */
 	} else {
 		return -1;	/* Invalid mode */
 	}


 	ax = 0x4f02;
 	bx = vesa_mode;
 	di = 0;
 	asm volatile(INT10
 		     : "+a" (ax), "+b" (bx), "+D" (di)
 		     : : "ecx", "edx", "esi");

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

 	graphic_mode = is_graphic;
 	if (!is_graphic) {
 		/* Text mode */
 		force_x = mode->x;
 		force_y = mode->y;
 		do_restore = 1;
 	} else {
 		/* Graphics mode */
 		vesa_store_mode_params_graphics();
 	}

 	return 0;
 }


 /* Switch DAC to 8-bit mode */
 static void vesa_dac_set_8bits(void)
 {
 	u8 dac_size = 6;

 	/* If possible, switch the DAC to 8-bit mode */
 	if (vginfo.capabilities & 1) {
 		u16 ax, bx;

 		ax = 0x4f08;
 		bx = 0x0800;
 		asm volatile(INT10
 			     : "+a" (ax), "+b" (bx)
 			     : : "ecx", "edx", "esi", "edi");

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

 	/* Set the color sizes to the DAC size, and offsets to 0 */
 	boot_params.screen_info.red_size = dac_size;
 	boot_params.screen_info.green_size = dac_size;
 	boot_params.screen_info.blue_size = dac_size;
 	boot_params.screen_info.rsvd_size = dac_size;

 	boot_params.screen_info.red_pos = 0;
 	boot_params.screen_info.green_pos = 0;
 	boot_params.screen_info.blue_pos = 0;
 	boot_params.screen_info.rsvd_pos = 0;
 }

 /* Save the VESA protected mode info */
 static void vesa_store_pm_info(void)
 {
 	u16 ax, bx, di, es;

 	ax = 0x4f0a;
 	bx = di = 0;
 	asm("pushw %%es; "INT10"; movw %%es,%0; popw %%es"
 	    : "=d" (es), "+a" (ax), "+b" (bx), "+D" (di)
 	    : : "ecx", "esi");

 	if (ax != 0x004f)
 		return;

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

 /*
  * Save video mode parameters for graphics mode
  */
 static void vesa_store_mode_params_graphics(void)
 {
 	/* Tell the kernel we're in VESA graphics mode */
 	boot_params.screen_info.orig_video_isVGA = 0x23;

 	/* Mode parameters */
 	boot_params.screen_info.vesa_attributes = vminfo.mode_attr;
 	boot_params.screen_info.lfb_linelength = vminfo.logical_scan;
 	boot_params.screen_info.lfb_width = vminfo.h_res;
 	boot_params.screen_info.lfb_height = vminfo.v_res;
 	boot_params.screen_info.lfb_depth = vminfo.bpp;
 	boot_params.screen_info.pages = vminfo.image_planes;
 	boot_params.screen_info.lfb_base = vminfo.lfb_ptr;
 	memcpy(&boot_params.screen_info.red_size,
 	       &vminfo.rmask, 8);

 	/* General parameters */
 	boot_params.screen_info.lfb_size = vginfo.total_memory;

 	if (vminfo.bpp <= 8)
 		vesa_dac_set_8bits();

 	vesa_store_pm_info();
 }

 /*
  * Save EDID information for the kernel; this is invoked, separately,
  * after mode-setting.
  */
 void vesa_store_edid(void)
 {
 #ifdef CONFIG_FIRMWARE_EDID
 	u16 ax, bx, cx, dx, di;

 	/* Apparently used as a nonsense token... */
 	memset(&boot_params.edid_info, 0x13, sizeof boot_params.edid_info);

 	if (vginfo.version < 0x0200)
 		return;		/* EDID requires VBE 2.0+ */

 	ax = 0x4f15;		/* VBE DDC */
 	bx = 0x0000;		/* Report DDC capabilities */
 	cx = 0;			/* Controller 0 */
 	di = 0;			/* ES:DI must be 0 by spec */

 	/* Note: The VBE DDC spec is different from the main VESA spec;
 	   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");

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

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

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

 __videocard video_vesa =
 {
 	.card_name	= "VESA",
 	.probe		= vesa_probe,
 	.set_mode	= vesa_set_mode,
 	.xmode_first	= VIDEO_FIRST_VESA,
 	.xmode_n	= 0x200,
 };
	/* -- linux-c -- ------------------------------------------------------- *
	*
	* Copyright (C) 1991, 1992 Linus Torvalds
	* Copyright 2007 rPath, Inc. - All Rights Reserved
	*
	* This file is part of the Linux kernel, and is made available under
	* the terms of the GNU General Public License version 2.
	*
	* ----------------------------------------------------------------------- */

	/*
	* arch/i386/boot/video-vesa.c
	*
	* VESA text modes
	*/

	#include "boot.h"
	#include "video.h"
	#include "vesa.h"

	/* VESA information */
	static struct vesa_general_info vginfo;
	static struct vesa_mode_info vminfo;

	__videocard video_vesa;

	static void vesa_store_mode_params_graphics(void);

	static int vesa_probe(void)
	{
	#if defined(CONFIG_VIDEO_VESA) \|\| defined(CONFIG_FIRMWARE_EDID)
	u16 ax, cx, di;
	u16 mode;
	addr_t mode_ptr;
	struct mode_info *mi;
	int nmodes = 0;

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

	vginfo.signature = VBE2_MAGIC;

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

	if (ax != 0x004f \|\|
	vginfo.signature != VESA_MAGIC \|\|
	vginfo.version < 0x0102)
	return 0; /* Not present */
	#endif /* CONFIG_VIDEO_VESA \|\| CONFIG_FIRMWARE_EDID */
	#ifdef CONFIG_VIDEO_VESA
	set_fs(vginfo.video_mode_ptr.seg);
	mode_ptr = vginfo.video_mode_ptr.off;

	while ((mode = rdfs16(mode_ptr)) != 0xffff) {
	mode_ptr += 2;

	if (heap_free() < sizeof(struct mode_info))
	break; /* Heap full, can't save mode info */

	if (mode & ~0x1ff)
	continue;

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

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

	if (ax != 0x004f)
	continue;

	if ((vminfo.mode_attr & 0x15) == 0x05) {
	/* Text Mode, TTY BIOS supported,
	supported by hardware */
	mi = GET_HEAP(struct mode_info, 1);
	mi->mode = mode + VIDEO_FIRST_VESA;
	mi->x = vminfo.h_res;
	mi->y = vminfo.v_res;
	nmodes++;
	} else if ((vminfo.mode_attr & 0x99) == 0x99) {
	#ifdef CONFIG_FB
	/* Graphics mode, color, linear frame buffer
	supported -- register the mode but hide from
	the menu. Only do this if framebuffer is
	configured, however, otherwise the user will
	be left without a screen. */
	mi = GET_HEAP(struct mode_info, 1);
	mi->mode = mode + VIDEO_FIRST_VESA;
	mi->x = mi->y = 0;
	nmodes++;
	#endif
	}
	}

	return nmodes;
	#else
	return 0;
	#endif /* CONFIG_VIDEO_VESA */
	}

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

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

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

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

	if ((vminfo.mode_attr & 0x15) == 0x05) {
	/* It's a supported text mode */
	is_graphic = 0;
	} else if ((vminfo.mode_attr & 0x99) == 0x99) {
	/* It's a graphics mode with linear frame buffer */
	is_graphic = 1;
	vesa_mode \|= 0x4000; /* Request linear frame buffer */
	} else {
	return -1; /* Invalid mode */
	}


	ax = 0x4f02;
	bx = vesa_mode;
	di = 0;
	asm volatile(INT10
	: "+a" (ax), "+b" (bx), "+D" (di)
	: : "ecx", "edx", "esi");

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

	graphic_mode = is_graphic;
	if (!is_graphic) {
	/* Text mode */
	force_x = mode->x;
	force_y = mode->y;
	do_restore = 1;
	} else {
	/* Graphics mode */
	vesa_store_mode_params_graphics();
	}

	return 0;
	}


	/* Switch DAC to 8-bit mode */
	static void vesa_dac_set_8bits(void)
	{
	u8 dac_size = 6;

	/* If possible, switch the DAC to 8-bit mode */
	if (vginfo.capabilities & 1) {
	u16 ax, bx;

	ax = 0x4f08;
	bx = 0x0800;
	asm volatile(INT10
	: "+a" (ax), "+b" (bx)
	: : "ecx", "edx", "esi", "edi");

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

	/* Set the color sizes to the DAC size, and offsets to 0 */
	boot_params.screen_info.red_size = dac_size;
	boot_params.screen_info.green_size = dac_size;
	boot_params.screen_info.blue_size = dac_size;
	boot_params.screen_info.rsvd_size = dac_size;

	boot_params.screen_info.red_pos = 0;
	boot_params.screen_info.green_pos = 0;
	boot_params.screen_info.blue_pos = 0;
	boot_params.screen_info.rsvd_pos = 0;
	}

	/* Save the VESA protected mode info */
	static void vesa_store_pm_info(void)
	{
	u16 ax, bx, di, es;

	ax = 0x4f0a;
	bx = di = 0;
	asm("pushw %%es; "INT10"; movw %%es,%0; popw %%es"
	: "=d" (es), "+a" (ax), "+b" (bx), "+D" (di)
	: : "ecx", "esi");

	if (ax != 0x004f)
	return;

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

	/*
	* Save video mode parameters for graphics mode
	*/
	static void vesa_store_mode_params_graphics(void)
	{
	/* Tell the kernel we're in VESA graphics mode */
	boot_params.screen_info.orig_video_isVGA = 0x23;

	/* Mode parameters */
	boot_params.screen_info.vesa_attributes = vminfo.mode_attr;
	boot_params.screen_info.lfb_linelength = vminfo.logical_scan;
	boot_params.screen_info.lfb_width = vminfo.h_res;
	boot_params.screen_info.lfb_height = vminfo.v_res;
	boot_params.screen_info.lfb_depth = vminfo.bpp;
	boot_params.screen_info.pages = vminfo.image_planes;
	boot_params.screen_info.lfb_base = vminfo.lfb_ptr;
	memcpy(&boot_params.screen_info.red_size,
	&vminfo.rmask, 8);

	/* General parameters */
	boot_params.screen_info.lfb_size = vginfo.total_memory;

	if (vminfo.bpp <= 8)
	vesa_dac_set_8bits();

	vesa_store_pm_info();
	}

	/*
	* Save EDID information for the kernel; this is invoked, separately,
	* after mode-setting.
	*/
	void vesa_store_edid(void)
	{
	#ifdef CONFIG_FIRMWARE_EDID
	u16 ax, bx, cx, dx, di;

	/* Apparently used as a nonsense token... */
	memset(&boot_params.edid_info, 0x13, sizeof boot_params.edid_info);

	if (vginfo.version < 0x0200)
	return; /* EDID requires VBE 2.0+ */

	ax = 0x4f15; /* VBE DDC */
	bx = 0x0000; /* Report DDC capabilities */
	cx = 0; /* Controller 0 */
	di = 0; /* ES:DI must be 0 by spec */

	/* Note: The VBE DDC spec is different from the main VESA spec;
	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");

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

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

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

	__videocard video_vesa =
	{
	.card_name = "VESA",
	.probe = vesa_probe,
	.set_mode = vesa_set_mode,
	.xmode_first = VIDEO_FIRST_VESA,
	.xmode_n = 0x200,
	};