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Release 4.14 arch/x86/boot/video-vga.c

Directory: arch/x86/boot
/* -*- linux-c -*- ------------------------------------------------------- *
 *
 *   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.
 *
 * ----------------------------------------------------------------------- */

/*
 * Common all-VGA modes
 */

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


static struct mode_info vga_modes[] = {
	{ VIDEO_80x25,  80, 25, 0 },
	{ VIDEO_8POINT, 80, 50, 0 },
	{ VIDEO_80x43,  80, 43, 0 },
	{ VIDEO_80x28,  80, 28, 0 },
	{ VIDEO_80x30,  80, 30, 0 },
	{ VIDEO_80x34,  80, 34, 0 },
	{ VIDEO_80x60,  80, 60, 0 },
};


static struct mode_info ega_modes[] = {
	{ VIDEO_80x25,  80, 25, 0 },
	{ VIDEO_8POINT, 80, 43, 0 },
};


static struct mode_info cga_modes[] = {
	{ VIDEO_80x25,  80, 25, 0 },
};


static __videocard video_vga;

/* Set basic 80x25 mode */

static u8 vga_set_basic_mode(void) { struct biosregs ireg, oreg; u8 mode; initregs(&ireg); /* Query current mode */ ireg.ax = 0x0f00; intcall(0x10, &ireg, &oreg); mode = oreg.al; if (mode != 3 && mode != 7) mode = 3; /* Set the mode */ ireg.ax = mode; /* AH=0: set mode */ intcall(0x10, &ireg, NULL); do_restore = 1; return mode; }

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H. Peter Anvin8497.67%480.00%
Andi Kleen22.33%120.00%
Total86100.00%5100.00%


static void vga_set_8font(void) { /* Set 8x8 font - 80x43 on EGA, 80x50 on VGA */ struct biosregs ireg; initregs(&ireg); /* Set 8x8 font */ ireg.ax = 0x1112; /* ireg.bl = 0; */ intcall(0x10, &ireg, NULL); /* Use alternate print screen */ ireg.ax = 0x1200; ireg.bl = 0x20; intcall(0x10, &ireg, NULL); /* Turn off cursor emulation */ ireg.ax = 0x1201; ireg.bl = 0x34; intcall(0x10, &ireg, NULL); /* Cursor is scan lines 6-7 */ ireg.ax = 0x0100; ireg.cx = 0x0607; intcall(0x10, &ireg, NULL); }

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PersonTokensPropCommitsCommitProp
H. Peter Anvin106100.00%2100.00%
Total106100.00%2100.00%


static void vga_set_14font(void) { /* Set 9x14 font - 80x28 on VGA */ struct biosregs ireg; initregs(&ireg); /* Set 9x14 font */ ireg.ax = 0x1111; /* ireg.bl = 0; */ intcall(0x10, &ireg, NULL); /* Turn off cursor emulation */ ireg.ax = 0x1201; ireg.bl = 0x34; intcall(0x10, &ireg, NULL); /* Cursor is scan lines 11-12 */ ireg.ax = 0x0100; ireg.cx = 0x0b0c; intcall(0x10, &ireg, NULL); }

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H. Peter Anvin83100.00%2100.00%
Total83100.00%2100.00%


static void vga_set_80x43(void) { /* Set 80x43 mode on VGA (not EGA) */ struct biosregs ireg; initregs(&ireg); /* Set 350 scans */ ireg.ax = 0x1201; ireg.bl = 0x30; intcall(0x10, &ireg, NULL); /* Reset video mode */ ireg.ax = 0x0003; intcall(0x10, &ireg, NULL); vga_set_8font(); }

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H. Peter Anvin62100.00%2100.00%
Total62100.00%2100.00%

/* I/O address of the VGA CRTC */
u16 vga_crtc(void) { return (inb(0x3cc) & 1) ? 0x3d4 : 0x3b4; }

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H. Peter Anvin21100.00%1100.00%
Total21100.00%1100.00%


static void vga_set_480_scanlines(void) { u16 crtc; /* CRTC base address */ u8 csel; /* CRTC miscellaneous output register */ crtc = vga_crtc(); out_idx(0x0c, crtc, 0x11); /* Vertical sync end, unlock CR0-7 */ out_idx(0x0b, crtc, 0x06); /* Vertical total */ out_idx(0x3e, crtc, 0x07); /* Vertical overflow */ out_idx(0xea, crtc, 0x10); /* Vertical sync start */ out_idx(0xdf, crtc, 0x12); /* Vertical display end */ out_idx(0xe7, crtc, 0x15); /* Vertical blank start */ out_idx(0x04, crtc, 0x16); /* Vertical blank end */ csel = inb(0x3cc); csel &= 0x0d; csel |= 0xe2; outb(csel, 0x3c2); }

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H. Peter Anvin113100.00%3100.00%
Total113100.00%3100.00%


static void vga_set_vertical_end(int lines) { u16 crtc; /* CRTC base address */ u8 ovfw; /* CRTC overflow register */ int end = lines-1; crtc = vga_crtc(); ovfw = 0x3c | ((end >> (8-1)) & 0x02) | ((end >> (9-6)) & 0x40); out_idx(ovfw, crtc, 0x07); /* Vertical overflow */ out_idx(end, crtc, 0x12); /* Vertical display end */ }

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H. Peter Anvin81100.00%1100.00%
Total81100.00%1100.00%


static void vga_set_80x30(void) { vga_set_480_scanlines(); vga_set_vertical_end(30*16); }

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H. Peter Anvin18100.00%3100.00%
Total18100.00%3100.00%


static void vga_set_80x34(void) { vga_set_480_scanlines(); vga_set_14font(); vga_set_vertical_end(34*14); }

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H. Peter Anvin21100.00%3100.00%
Total21100.00%3100.00%


static void vga_set_80x60(void) { vga_set_480_scanlines(); vga_set_8font(); vga_set_vertical_end(60*8); }

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H. Peter Anvin21100.00%3100.00%
Total21100.00%3100.00%


static int vga_set_mode(struct mode_info *mode) { /* Set the basic mode */ vga_set_basic_mode(); /* Override a possibly broken BIOS */ force_x = mode->x; force_y = mode->y; switch (mode->mode) { case VIDEO_80x25: break; case VIDEO_8POINT: vga_set_8font(); break; case VIDEO_80x43: vga_set_80x43(); break; case VIDEO_80x28: vga_set_14font(); break; case VIDEO_80x30: vga_set_80x30(); break; case VIDEO_80x34: vga_set_80x34(); break; case VIDEO_80x60: vga_set_80x60(); break; } return 0; }

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PersonTokensPropCommitsCommitProp
H. Peter Anvin85100.00%1100.00%
Total85100.00%1100.00%

/* * Note: this probe includes basic information required by all * systems. It should be executed first, by making sure * video-vga.c is listed first in the Makefile. */
static int vga_probe(void) { static const char *card_name[] = { "CGA/MDA/HGC", "EGA", "VGA" }; static struct mode_info *mode_lists[] = { cga_modes, ega_modes, vga_modes, }; static int mode_count[] = { sizeof(cga_modes)/sizeof(struct mode_info), sizeof(ega_modes)/sizeof(struct mode_info), sizeof(vga_modes)/sizeof(struct mode_info), }; struct biosregs ireg, oreg; initregs(&ireg); ireg.ax = 0x1200; ireg.bl = 0x10; /* Check EGA/VGA */ intcall(0x10, &ireg, &oreg); #ifndef _WAKEUP boot_params.screen_info.orig_video_ega_bx = oreg.bx; #endif /* If we have MDA/CGA/HGC then BL will be unchanged at 0x10 */ if (oreg.bl != 0x10) { /* EGA/VGA */ ireg.ax = 0x1a00; intcall(0x10, &ireg, &oreg); if (oreg.al == 0x1a) { adapter = ADAPTER_VGA; #ifndef _WAKEUP boot_params.screen_info.orig_video_isVGA = 1; #endif } else { adapter = ADAPTER_EGA; } } else { adapter = ADAPTER_CGA; } video_vga.modes = mode_lists[adapter]; video_vga.card_name = card_name[adapter]; return mode_count[adapter]; }

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PersonTokensPropCommitsCommitProp
H. Peter Anvin20692.38%266.67%
Pavel Machek177.62%133.33%
Total223100.00%3100.00%

static __videocard video_vga = { .card_name = "VGA", .probe = vga_probe, .set_mode = vga_set_mode, };

Overall Contributors

PersonTokensPropCommitsCommitProp
H. Peter Anvin105897.96%763.64%
Pavel Machek171.57%19.09%
Hannes Eder20.19%19.09%
Andi Kleen20.19%19.09%
Américo Wang10.09%19.09%
Total1080100.00%11100.00%
Directory: arch/x86/boot
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