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Diffstat (limited to 'arch/x86/boot/video-vga.c')
| -rw-r--r-- | arch/x86/boot/video-vga.c | 261 |
1 files changed, 261 insertions, 0 deletions
diff --git a/arch/x86/boot/video-vga.c b/arch/x86/boot/video-vga.c new file mode 100644 index 00000000000..aef02f9ec0c --- /dev/null +++ b/arch/x86/boot/video-vga.c @@ -0,0 +1,261 @@ +/* -*- 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-vga.c + * + * Common all-VGA modes + */ + +#include "boot.h" +#include "video.h" + +static struct mode_info vga_modes[] = { + { VIDEO_80x25, 80, 25 }, + { VIDEO_8POINT, 80, 50 }, + { VIDEO_80x43, 80, 43 }, + { VIDEO_80x28, 80, 28 }, + { VIDEO_80x30, 80, 30 }, + { VIDEO_80x34, 80, 34 }, + { VIDEO_80x60, 80, 60 }, +}; + +static struct mode_info ega_modes[] = { + { VIDEO_80x25, 80, 25 }, + { VIDEO_8POINT, 80, 43 }, +}; + +static struct mode_info cga_modes[] = { + { VIDEO_80x25, 80, 25 }, +}; + +__videocard video_vga; + +/* Set basic 80x25 mode */ +static u8 vga_set_basic_mode(void) +{ + u16 ax; + u8 rows; + u8 mode; + +#ifdef CONFIG_VIDEO_400_HACK + if (adapter >= ADAPTER_VGA) { + asm volatile(INT10 + : : "a" (0x1202), "b" (0x0030) + : "ecx", "edx", "esi", "edi"); + } +#endif + + ax = 0x0f00; + asm volatile(INT10 + : "+a" (ax) + : : "ebx", "ecx", "edx", "esi", "edi"); + + mode = (u8)ax; + + set_fs(0); + rows = rdfs8(0x484); /* rows minus one */ + +#ifndef CONFIG_VIDEO_400_HACK + if ((ax == 0x5003 || ax == 0x5007) && + (rows == 0 || rows == 24)) + return mode; +#endif + + if (mode != 3 && mode != 7) + mode = 3; + + /* Set the mode */ + ax = mode; + asm volatile(INT10 + : "+a" (ax) + : : "ebx", "ecx", "edx", "esi", "edi"); + do_restore = 1; + return mode; +} + +static void vga_set_8font(void) +{ + /* Set 8x8 font - 80x43 on EGA, 80x50 on VGA */ + + /* Set 8x8 font */ + asm volatile(INT10 : : "a" (0x1112), "b" (0)); + + /* Use alternate print screen */ + asm volatile(INT10 : : "a" (0x1200), "b" (0x20)); + + /* Turn off cursor emulation */ + asm volatile(INT10 : : "a" (0x1201), "b" (0x34)); + + /* Cursor is scan lines 6-7 */ + asm volatile(INT10 : : "a" (0x0100), "c" (0x0607)); +} + +static void vga_set_14font(void) +{ + /* Set 9x14 font - 80x28 on VGA */ + + /* Set 9x14 font */ + asm volatile(INT10 : : "a" (0x1111), "b" (0)); + + /* Turn off cursor emulation */ + asm volatile(INT10 : : "a" (0x1201), "b" (0x34)); + + /* Cursor is scan lines 11-12 */ + asm volatile(INT10 : : "a" (0x0100), "c" (0x0b0c)); +} + +static void vga_set_80x43(void) +{ + /* Set 80x43 mode on VGA (not EGA) */ + + /* Set 350 scans */ + asm volatile(INT10 : : "a" (0x1201), "b" (0x30)); + + /* Reset video mode */ + asm volatile(INT10 : : "a" (0x0003)); + + vga_set_8font(); +} + +/* I/O address of the VGA CRTC */ +u16 vga_crtc(void) +{ + return (inb(0x3cc) & 1) ? 0x3d4 : 0x3b4; +} + +static void vga_set_480_scanlines(int end) +{ + u16 crtc; + u8 csel; + + 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(end, 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, 0x3cc); +} + +static void vga_set_80x30(void) +{ + vga_set_480_scanlines(0xdf); +} + +static void vga_set_80x34(void) +{ + vga_set_14font(); + vga_set_480_scanlines(0xdb); +} + +static void vga_set_80x60(void) +{ + vga_set_8font(); + vga_set_480_scanlines(0xdf); +} + +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; +} + +/* + * 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), + }; + u8 vga_flag; + + asm(INT10 + : "=b" (boot_params.screen_info.orig_video_ega_bx) + : "a" (0x1200), "b" (0x10) /* Check EGA/VGA */ + : "ecx", "edx", "esi", "edi"); + + /* If we have MDA/CGA/HGC then BL will be unchanged at 0x10 */ + if ((u8)boot_params.screen_info.orig_video_ega_bx != 0x10) { + /* EGA/VGA */ + asm(INT10 + : "=a" (vga_flag) + : "a" (0x1a00) + : "ebx", "ecx", "edx", "esi", "edi"); + + if (vga_flag == 0x1a) { + adapter = ADAPTER_VGA; + boot_params.screen_info.orig_video_isVGA = 1; + } 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]; +} + +__videocard video_vga = +{ + .card_name = "VGA", + .probe = vga_probe, + .set_mode = vga_set_mode, +}; |