1 /* -*- linux-c -*- ------------------------------------------------------- *
2 *
3 * Copyright (C) 1991, 1992 Linus Torvalds
4 * Copyright 2007 rPath, Inc. - All Rights Reserved
5 *
6 * This file is part of the Linux kernel, and is made available under
7 * the terms of the GNU General Public License version 2.
8 *
9 * ----------------------------------------------------------------------- */
10
11 /*
12 * Common all-VGA modes
13 */
14
15 #include "boot.h"
16 #include "video.h"
17
18 static struct mode_info vga_modes[] = {
19 { VIDEO_80x25, 80, 25, 0 },
20 { VIDEO_8POINT, 80, 50, 0 },
21 { VIDEO_80x43, 80, 43, 0 },
22 { VIDEO_80x28, 80, 28, 0 },
23 { VIDEO_80x30, 80, 30, 0 },
24 { VIDEO_80x34, 80, 34, 0 },
25 { VIDEO_80x60, 80, 60, 0 },
26 };
27
28 static struct mode_info ega_modes[] = {
29 { VIDEO_80x25, 80, 25, 0 },
30 { VIDEO_8POINT, 80, 43, 0 },
31 };
32
33 static struct mode_info cga_modes[] = {
34 { VIDEO_80x25, 80, 25, 0 },
35 };
36
37 static __videocard video_vga;
38
39 /* Set basic 80x25 mode */
vga_set_basic_mode(void)40 static u8 vga_set_basic_mode(void)
41 {
42 u16 ax;
43 u8 rows;
44 u8 mode;
45
46 #ifdef CONFIG_VIDEO_400_HACK
47 if (adapter >= ADAPTER_VGA) {
48 asm volatile(INT10
49 : : "a" (0x1202), "b" (0x0030)
50 : "ecx", "edx", "esi", "edi");
51 }
52 #endif
53
54 ax = 0x0f00;
55 asm volatile(INT10
56 : "+a" (ax)
57 : : "ebx", "ecx", "edx", "esi", "edi");
58
59 mode = (u8)ax;
60
61 set_fs(0);
62 rows = rdfs8(0x484); /* rows minus one */
63
64 #ifndef CONFIG_VIDEO_400_HACK
65 if ((ax == 0x5003 || ax == 0x5007) &&
66 (rows == 0 || rows == 24))
67 return mode;
68 #endif
69
70 if (mode != 3 && mode != 7)
71 mode = 3;
72
73 /* Set the mode */
74 ax = mode;
75 asm volatile(INT10
76 : "+a" (ax)
77 : : "ebx", "ecx", "edx", "esi", "edi");
78 do_restore = 1;
79 return mode;
80 }
81
vga_set_8font(void)82 static void vga_set_8font(void)
83 {
84 /* Set 8x8 font - 80x43 on EGA, 80x50 on VGA */
85
86 /* Set 8x8 font */
87 asm volatile(INT10 : : "a" (0x1112), "b" (0));
88
89 /* Use alternate print screen */
90 asm volatile(INT10 : : "a" (0x1200), "b" (0x20));
91
92 /* Turn off cursor emulation */
93 asm volatile(INT10 : : "a" (0x1201), "b" (0x34));
94
95 /* Cursor is scan lines 6-7 */
96 asm volatile(INT10 : : "a" (0x0100), "c" (0x0607));
97 }
98
vga_set_14font(void)99 static void vga_set_14font(void)
100 {
101 /* Set 9x14 font - 80x28 on VGA */
102
103 /* Set 9x14 font */
104 asm volatile(INT10 : : "a" (0x1111), "b" (0));
105
106 /* Turn off cursor emulation */
107 asm volatile(INT10 : : "a" (0x1201), "b" (0x34));
108
109 /* Cursor is scan lines 11-12 */
110 asm volatile(INT10 : : "a" (0x0100), "c" (0x0b0c));
111 }
112
vga_set_80x43(void)113 static void vga_set_80x43(void)
114 {
115 /* Set 80x43 mode on VGA (not EGA) */
116
117 /* Set 350 scans */
118 asm volatile(INT10 : : "a" (0x1201), "b" (0x30));
119
120 /* Reset video mode */
121 asm volatile(INT10 : : "a" (0x0003));
122
123 vga_set_8font();
124 }
125
126 /* I/O address of the VGA CRTC */
vga_crtc(void)127 u16 vga_crtc(void)
128 {
129 return (inb(0x3cc) & 1) ? 0x3d4 : 0x3b4;
130 }
131
vga_set_480_scanlines(int end)132 static void vga_set_480_scanlines(int end)
133 {
134 u16 crtc;
135 u8 csel;
136
137 crtc = vga_crtc();
138
139 out_idx(0x0c, crtc, 0x11); /* Vertical sync end, unlock CR0-7 */
140 out_idx(0x0b, crtc, 0x06); /* Vertical total */
141 out_idx(0x3e, crtc, 0x07); /* Vertical overflow */
142 out_idx(0xea, crtc, 0x10); /* Vertical sync start */
143 out_idx(end, crtc, 0x12); /* Vertical display end */
144 out_idx(0xe7, crtc, 0x15); /* Vertical blank start */
145 out_idx(0x04, crtc, 0x16); /* Vertical blank end */
146 csel = inb(0x3cc);
147 csel &= 0x0d;
148 csel |= 0xe2;
149 outb(csel, 0x3cc);
150 }
151
vga_set_80x30(void)152 static void vga_set_80x30(void)
153 {
154 vga_set_480_scanlines(0xdf);
155 }
156
vga_set_80x34(void)157 static void vga_set_80x34(void)
158 {
159 vga_set_14font();
160 vga_set_480_scanlines(0xdb);
161 }
162
vga_set_80x60(void)163 static void vga_set_80x60(void)
164 {
165 vga_set_8font();
166 vga_set_480_scanlines(0xdf);
167 }
168
vga_set_mode(struct mode_info * mode)169 static int vga_set_mode(struct mode_info *mode)
170 {
171 /* Set the basic mode */
172 vga_set_basic_mode();
173
174 /* Override a possibly broken BIOS */
175 force_x = mode->x;
176 force_y = mode->y;
177
178 switch (mode->mode) {
179 case VIDEO_80x25:
180 break;
181 case VIDEO_8POINT:
182 vga_set_8font();
183 break;
184 case VIDEO_80x43:
185 vga_set_80x43();
186 break;
187 case VIDEO_80x28:
188 vga_set_14font();
189 break;
190 case VIDEO_80x30:
191 vga_set_80x30();
192 break;
193 case VIDEO_80x34:
194 vga_set_80x34();
195 break;
196 case VIDEO_80x60:
197 vga_set_80x60();
198 break;
199 }
200
201 return 0;
202 }
203
204 /*
205 * Note: this probe includes basic information required by all
206 * systems. It should be executed first, by making sure
207 * video-vga.c is listed first in the Makefile.
208 */
vga_probe(void)209 static int vga_probe(void)
210 {
211 u16 ega_bx;
212
213 static const char *card_name[] = {
214 "CGA/MDA/HGC", "EGA", "VGA"
215 };
216 static struct mode_info *mode_lists[] = {
217 cga_modes,
218 ega_modes,
219 vga_modes,
220 };
221 static int mode_count[] = {
222 sizeof(cga_modes)/sizeof(struct mode_info),
223 sizeof(ega_modes)/sizeof(struct mode_info),
224 sizeof(vga_modes)/sizeof(struct mode_info),
225 };
226 u8 vga_flag;
227
228 asm(INT10
229 : "=b" (ega_bx)
230 : "a" (0x1200), "b" (0x10) /* Check EGA/VGA */
231 : "ecx", "edx", "esi", "edi");
232
233 #ifndef _WAKEUP
234 boot_params.screen_info.orig_video_ega_bx = ega_bx;
235 #endif
236
237 /* If we have MDA/CGA/HGC then BL will be unchanged at 0x10 */
238 if ((u8)ega_bx != 0x10) {
239 /* EGA/VGA */
240 asm(INT10
241 : "=a" (vga_flag)
242 : "a" (0x1a00)
243 : "ebx", "ecx", "edx", "esi", "edi");
244
245 if (vga_flag == 0x1a) {
246 adapter = ADAPTER_VGA;
247 #ifndef _WAKEUP
248 boot_params.screen_info.orig_video_isVGA = 1;
249 #endif
250 } else {
251 adapter = ADAPTER_EGA;
252 }
253 } else {
254 adapter = ADAPTER_CGA;
255 }
256
257 video_vga.modes = mode_lists[adapter];
258 video_vga.card_name = card_name[adapter];
259 return mode_count[adapter];
260 }
261
262 static __videocard video_vga = {
263 .card_name = "VGA",
264 .probe = vga_probe,
265 .set_mode = vga_set_mode,
266 };
267