1 /* -*- linux-c -*- ------------------------------------------------------- *
2  *
3  *   Copyright (C) 1991, 1992 Linus Torvalds
4  *   Copyright 2007 rPath, Inc. - All Rights Reserved
5  *   Copyright 2009 Intel Corporation; author H. Peter Anvin
6  *
7  *   This file is part of the Linux kernel, and is made available under
8  *   the terms of the GNU General Public License version 2.
9  *
10  * ----------------------------------------------------------------------- */
11 
12 /*
13  * VESA text modes
14  */
15 
16 #include "boot.h"
17 #include "video.h"
18 #include "vesa.h"
19 
20 /* VESA information */
21 static struct vesa_general_info vginfo;
22 static struct vesa_mode_info vminfo;
23 
24 static __videocard video_vesa;
25 
26 #ifndef _WAKEUP
27 static void vesa_store_mode_params_graphics(void);
28 #else /* _WAKEUP */
vesa_store_mode_params_graphics(void)29 static inline void vesa_store_mode_params_graphics(void) {}
30 #endif /* _WAKEUP */
31 
vesa_probe(void)32 static int vesa_probe(void)
33 {
34 	struct biosregs ireg, oreg;
35 	u16 mode;
36 	addr_t mode_ptr;
37 	struct mode_info *mi;
38 	int nmodes = 0;
39 
40 	video_vesa.modes = GET_HEAP(struct mode_info, 0);
41 
42 	initregs(&ireg);
43 	ireg.ax = 0x4f00;
44 	ireg.di = (size_t)&vginfo;
45 	intcall(0x10, &ireg, &oreg);
46 
47 	if (oreg.ax != 0x004f ||
48 	    vginfo.signature != VESA_MAGIC ||
49 	    vginfo.version < 0x0102)
50 		return 0;	/* Not present */
51 
52 	set_fs(vginfo.video_mode_ptr.seg);
53 	mode_ptr = vginfo.video_mode_ptr.off;
54 
55 	while ((mode = rdfs16(mode_ptr)) != 0xffff) {
56 		mode_ptr += 2;
57 
58 		if (!heap_free(sizeof(struct mode_info)))
59 			break;	/* Heap full, can't save mode info */
60 
61 		if (mode & ~0x1ff)
62 			continue;
63 
64 		memset(&vminfo, 0, sizeof vminfo); /* Just in case... */
65 
66 		ireg.ax = 0x4f01;
67 		ireg.cx = mode;
68 		ireg.di = (size_t)&vminfo;
69 		intcall(0x10, &ireg, &oreg);
70 
71 		if (oreg.ax != 0x004f)
72 			continue;
73 
74 		if ((vminfo.mode_attr & 0x15) == 0x05) {
75 			/* Text Mode, TTY BIOS supported,
76 			   supported by hardware */
77 			mi = GET_HEAP(struct mode_info, 1);
78 			mi->mode  = mode + VIDEO_FIRST_VESA;
79 			mi->depth = 0; /* text */
80 			mi->x     = vminfo.h_res;
81 			mi->y     = vminfo.v_res;
82 			nmodes++;
83 		} else if ((vminfo.mode_attr & 0x99) == 0x99 &&
84 			   (vminfo.memory_layout == 4 ||
85 			    vminfo.memory_layout == 6) &&
86 			   vminfo.memory_planes == 1) {
87 #ifdef CONFIG_FB_BOOT_VESA_SUPPORT
88 			/* Graphics mode, color, linear frame buffer
89 			   supported.  Only register the mode if
90 			   if framebuffer is configured, however,
91 			   otherwise the user will be left without a screen. */
92 			mi = GET_HEAP(struct mode_info, 1);
93 			mi->mode = mode + VIDEO_FIRST_VESA;
94 			mi->depth = vminfo.bpp;
95 			mi->x = vminfo.h_res;
96 			mi->y = vminfo.v_res;
97 			nmodes++;
98 #endif
99 		}
100 	}
101 
102 	return nmodes;
103 }
104 
vesa_set_mode(struct mode_info * mode)105 static int vesa_set_mode(struct mode_info *mode)
106 {
107 	struct biosregs ireg, oreg;
108 	int is_graphic;
109 	u16 vesa_mode = mode->mode - VIDEO_FIRST_VESA;
110 
111 	memset(&vminfo, 0, sizeof vminfo); /* Just in case... */
112 
113 	initregs(&ireg);
114 	ireg.ax = 0x4f01;
115 	ireg.cx = vesa_mode;
116 	ireg.di = (size_t)&vminfo;
117 	intcall(0x10, &ireg, &oreg);
118 
119 	if (oreg.ax != 0x004f)
120 		return -1;
121 
122 	if ((vminfo.mode_attr & 0x15) == 0x05) {
123 		/* It's a supported text mode */
124 		is_graphic = 0;
125 #ifdef CONFIG_FB_BOOT_VESA_SUPPORT
126 	} else if ((vminfo.mode_attr & 0x99) == 0x99) {
127 		/* It's a graphics mode with linear frame buffer */
128 		is_graphic = 1;
129 		vesa_mode |= 0x4000; /* Request linear frame buffer */
130 #endif
131 	} else {
132 		return -1;	/* Invalid mode */
133 	}
134 
135 
136 	initregs(&ireg);
137 	ireg.ax = 0x4f02;
138 	ireg.bx = vesa_mode;
139 	intcall(0x10, &ireg, &oreg);
140 
141 	if (oreg.ax != 0x004f)
142 		return -1;
143 
144 	graphic_mode = is_graphic;
145 	if (!is_graphic) {
146 		/* Text mode */
147 		force_x = mode->x;
148 		force_y = mode->y;
149 		do_restore = 1;
150 	} else {
151 		/* Graphics mode */
152 		vesa_store_mode_params_graphics();
153 	}
154 
155 	return 0;
156 }
157 
158 
159 #ifndef _WAKEUP
160 
161 /* Switch DAC to 8-bit mode */
vesa_dac_set_8bits(void)162 static void vesa_dac_set_8bits(void)
163 {
164 	struct biosregs ireg, oreg;
165 	u8 dac_size = 6;
166 
167 	/* If possible, switch the DAC to 8-bit mode */
168 	if (vginfo.capabilities & 1) {
169 		initregs(&ireg);
170 		ireg.ax = 0x4f08;
171 		ireg.bh = 0x08;
172 		intcall(0x10, &ireg, &oreg);
173 		if (oreg.ax == 0x004f)
174 			dac_size = oreg.bh;
175 	}
176 
177 	/* Set the color sizes to the DAC size, and offsets to 0 */
178 	boot_params.screen_info.red_size   = dac_size;
179 	boot_params.screen_info.green_size = dac_size;
180 	boot_params.screen_info.blue_size  = dac_size;
181 	boot_params.screen_info.rsvd_size  = dac_size;
182 
183 	boot_params.screen_info.red_pos    = 0;
184 	boot_params.screen_info.green_pos  = 0;
185 	boot_params.screen_info.blue_pos   = 0;
186 	boot_params.screen_info.rsvd_pos   = 0;
187 }
188 
189 /* Save the VESA protected mode info */
vesa_store_pm_info(void)190 static void vesa_store_pm_info(void)
191 {
192 	struct biosregs ireg, oreg;
193 
194 	initregs(&ireg);
195 	ireg.ax = 0x4f0a;
196 	intcall(0x10, &ireg, &oreg);
197 
198 	if (oreg.ax != 0x004f)
199 		return;
200 
201 	boot_params.screen_info.vesapm_seg = oreg.es;
202 	boot_params.screen_info.vesapm_off = oreg.di;
203 }
204 
205 /*
206  * Save video mode parameters for graphics mode
207  */
vesa_store_mode_params_graphics(void)208 static void vesa_store_mode_params_graphics(void)
209 {
210 	/* Tell the kernel we're in VESA graphics mode */
211 	boot_params.screen_info.orig_video_isVGA = VIDEO_TYPE_VLFB;
212 
213 	/* Mode parameters */
214 	boot_params.screen_info.vesa_attributes = vminfo.mode_attr;
215 	boot_params.screen_info.lfb_linelength = vminfo.logical_scan;
216 	boot_params.screen_info.lfb_width = vminfo.h_res;
217 	boot_params.screen_info.lfb_height = vminfo.v_res;
218 	boot_params.screen_info.lfb_depth = vminfo.bpp;
219 	boot_params.screen_info.pages = vminfo.image_planes;
220 	boot_params.screen_info.lfb_base = vminfo.lfb_ptr;
221 	memcpy(&boot_params.screen_info.red_size,
222 	       &vminfo.rmask, 8);
223 
224 	/* General parameters */
225 	boot_params.screen_info.lfb_size = vginfo.total_memory;
226 
227 	if (vminfo.bpp <= 8)
228 		vesa_dac_set_8bits();
229 
230 	vesa_store_pm_info();
231 }
232 
233 /*
234  * Save EDID information for the kernel; this is invoked, separately,
235  * after mode-setting.
236  */
vesa_store_edid(void)237 void vesa_store_edid(void)
238 {
239 #ifdef CONFIG_FIRMWARE_EDID
240 	struct biosregs ireg, oreg;
241 
242 	/* Apparently used as a nonsense token... */
243 	memset(&boot_params.edid_info, 0x13, sizeof boot_params.edid_info);
244 
245 	if (vginfo.version < 0x0200)
246 		return;		/* EDID requires VBE 2.0+ */
247 
248 	initregs(&ireg);
249 	ireg.ax = 0x4f15;		/* VBE DDC */
250 	/* ireg.bx = 0x0000; */		/* Report DDC capabilities */
251 	/* ireg.cx = 0;	*/		/* Controller 0 */
252 	ireg.es = 0;			/* ES:DI must be 0 by spec */
253 	intcall(0x10, &ireg, &oreg);
254 
255 	if (oreg.ax != 0x004f)
256 		return;		/* No EDID */
257 
258 	/* BH = time in seconds to transfer EDD information */
259 	/* BL = DDC level supported */
260 
261 	ireg.ax = 0x4f15;		/* VBE DDC */
262 	ireg.bx = 0x0001;		/* Read EDID */
263 	/* ireg.cx = 0; */		/* Controller 0 */
264 	/* ireg.dx = 0;	*/		/* EDID block number */
265 	ireg.es = ds();
266 	ireg.di =(size_t)&boot_params.edid_info; /* (ES:)Pointer to block */
267 	intcall(0x10, &ireg, &oreg);
268 #endif /* CONFIG_FIRMWARE_EDID */
269 }
270 
271 #endif /* not _WAKEUP */
272 
273 static __videocard video_vesa =
274 {
275 	.card_name	= "VESA",
276 	.probe		= vesa_probe,
277 	.set_mode	= vesa_set_mode,
278 	.xmode_first	= VIDEO_FIRST_VESA,
279 	.xmode_n	= 0x200,
280 };
281