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-rw-r--r--arch/i386/boot/video-vga.c260
1 files changed, 260 insertions, 0 deletions
diff --git a/arch/i386/boot/video-vga.c b/arch/i386/boot/video-vga.c
new file mode 100644
index 000000000000..700d09a9c9b3
--- /dev/null
+++ b/arch/i386/boot/video-vga.c
@@ -0,0 +1,260 @@
+/* -*- 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(INT10
+ : : "a" (0x1202), "b" (0x0030)
+ : "ecx", "edx", "esi", "edi");
+ }
+#endif
+
+ ax = 0x0f00;
+ asm(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 */
+ asm volatile(INT10
+ : : "a" (mode)
+ : "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,
+};
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