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v3.15
 
  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#include "string.h"
 20
 21/* VESA information */
 22static struct vesa_general_info vginfo;
 23static struct vesa_mode_info vminfo;
 24
 25static __videocard video_vesa;
 26
 27#ifndef _WAKEUP
 28static void vesa_store_mode_params_graphics(void);
 29#else /* _WAKEUP */
 30static inline void vesa_store_mode_params_graphics(void) {}
 31#endif /* _WAKEUP */
 32
 33static int vesa_probe(void)
 34{
 35	struct biosregs ireg, oreg;
 36	u16 mode;
 37	addr_t mode_ptr;
 38	struct mode_info *mi;
 39	int nmodes = 0;
 40
 41	video_vesa.modes = GET_HEAP(struct mode_info, 0);
 42
 43	initregs(&ireg);
 44	ireg.ax = 0x4f00;
 45	ireg.di = (size_t)&vginfo;
 46	intcall(0x10, &ireg, &oreg);
 47
 48	if (oreg.ax != 0x004f ||
 49	    vginfo.signature != VESA_MAGIC ||
 50	    vginfo.version < 0x0102)
 51		return 0;	/* Not present */
 52
 53	set_fs(vginfo.video_mode_ptr.seg);
 54	mode_ptr = vginfo.video_mode_ptr.off;
 55
 56	while ((mode = rdfs16(mode_ptr)) != 0xffff) {
 57		mode_ptr += 2;
 58
 59		if (!heap_free(sizeof(struct mode_info)))
 60			break;	/* Heap full, can't save mode info */
 61
 62		if (mode & ~0x1ff)
 63			continue;
 64
 65		memset(&vminfo, 0, sizeof vminfo); /* Just in case... */
 66
 67		ireg.ax = 0x4f01;
 68		ireg.cx = mode;
 69		ireg.di = (size_t)&vminfo;
 70		intcall(0x10, &ireg, &oreg);
 71
 72		if (oreg.ax != 0x004f)
 73			continue;
 74
 75		if ((vminfo.mode_attr & 0x15) == 0x05) {
 76			/* Text Mode, TTY BIOS supported,
 77			   supported by hardware */
 78			mi = GET_HEAP(struct mode_info, 1);
 79			mi->mode  = mode + VIDEO_FIRST_VESA;
 80			mi->depth = 0; /* text */
 81			mi->x     = vminfo.h_res;
 82			mi->y     = vminfo.v_res;
 83			nmodes++;
 84		} else if ((vminfo.mode_attr & 0x99) == 0x99 &&
 85			   (vminfo.memory_layout == 4 ||
 86			    vminfo.memory_layout == 6) &&
 87			   vminfo.memory_planes == 1) {
 88#ifdef CONFIG_FB_BOOT_VESA_SUPPORT
 89			/* Graphics mode, color, linear frame buffer
 90			   supported.  Only register the mode if
 91			   if framebuffer is configured, however,
 92			   otherwise the user will be left without a screen. */
 93			mi = GET_HEAP(struct mode_info, 1);
 94			mi->mode = mode + VIDEO_FIRST_VESA;
 95			mi->depth = vminfo.bpp;
 96			mi->x = vminfo.h_res;
 97			mi->y = vminfo.v_res;
 98			nmodes++;
 99#endif
100		}
101	}
102
103	return nmodes;
104}
105
106static int vesa_set_mode(struct mode_info *mode)
107{
108	struct biosregs ireg, oreg;
109	int is_graphic;
110	u16 vesa_mode = mode->mode - VIDEO_FIRST_VESA;
111
112	memset(&vminfo, 0, sizeof vminfo); /* Just in case... */
113
114	initregs(&ireg);
115	ireg.ax = 0x4f01;
116	ireg.cx = vesa_mode;
117	ireg.di = (size_t)&vminfo;
118	intcall(0x10, &ireg, &oreg);
119
120	if (oreg.ax != 0x004f)
121		return -1;
122
123	if ((vminfo.mode_attr & 0x15) == 0x05) {
124		/* It's a supported text mode */
125		is_graphic = 0;
126#ifdef CONFIG_FB_BOOT_VESA_SUPPORT
127	} else if ((vminfo.mode_attr & 0x99) == 0x99) {
128		/* It's a graphics mode with linear frame buffer */
129		is_graphic = 1;
130		vesa_mode |= 0x4000; /* Request linear frame buffer */
131#endif
132	} else {
133		return -1;	/* Invalid mode */
134	}
135
136
137	initregs(&ireg);
138	ireg.ax = 0x4f02;
139	ireg.bx = vesa_mode;
140	intcall(0x10, &ireg, &oreg);
141
142	if (oreg.ax != 0x004f)
143		return -1;
144
145	graphic_mode = is_graphic;
146	if (!is_graphic) {
147		/* Text mode */
148		force_x = mode->x;
149		force_y = mode->y;
150		do_restore = 1;
151	} else {
152		/* Graphics mode */
153		vesa_store_mode_params_graphics();
154	}
155
156	return 0;
157}
158
159
160#ifndef _WAKEUP
161
162/* Switch DAC to 8-bit mode */
163static void vesa_dac_set_8bits(void)
164{
165	struct biosregs ireg, oreg;
166	u8 dac_size = 6;
167
168	/* If possible, switch the DAC to 8-bit mode */
169	if (vginfo.capabilities & 1) {
170		initregs(&ireg);
171		ireg.ax = 0x4f08;
172		ireg.bh = 0x08;
173		intcall(0x10, &ireg, &oreg);
174		if (oreg.ax == 0x004f)
175			dac_size = oreg.bh;
176	}
177
178	/* Set the color sizes to the DAC size, and offsets to 0 */
179	boot_params.screen_info.red_size   = dac_size;
180	boot_params.screen_info.green_size = dac_size;
181	boot_params.screen_info.blue_size  = dac_size;
182	boot_params.screen_info.rsvd_size  = dac_size;
183
184	boot_params.screen_info.red_pos    = 0;
185	boot_params.screen_info.green_pos  = 0;
186	boot_params.screen_info.blue_pos   = 0;
187	boot_params.screen_info.rsvd_pos   = 0;
188}
189
190/* Save the VESA protected mode info */
191static void vesa_store_pm_info(void)
192{
193	struct biosregs ireg, oreg;
194
195	initregs(&ireg);
196	ireg.ax = 0x4f0a;
197	intcall(0x10, &ireg, &oreg);
198
199	if (oreg.ax != 0x004f)
200		return;
201
202	boot_params.screen_info.vesapm_seg = oreg.es;
203	boot_params.screen_info.vesapm_off = oreg.di;
204}
205
206/*
207 * Save video mode parameters for graphics mode
208 */
209static void vesa_store_mode_params_graphics(void)
210{
211	/* Tell the kernel we're in VESA graphics mode */
212	boot_params.screen_info.orig_video_isVGA = VIDEO_TYPE_VLFB;
213
214	/* Mode parameters */
215	boot_params.screen_info.vesa_attributes = vminfo.mode_attr;
216	boot_params.screen_info.lfb_linelength = vminfo.logical_scan;
217	boot_params.screen_info.lfb_width = vminfo.h_res;
218	boot_params.screen_info.lfb_height = vminfo.v_res;
219	boot_params.screen_info.lfb_depth = vminfo.bpp;
220	boot_params.screen_info.pages = vminfo.image_planes;
221	boot_params.screen_info.lfb_base = vminfo.lfb_ptr;
222	memcpy(&boot_params.screen_info.red_size,
223	       &vminfo.rmask, 8);
224
225	/* General parameters */
226	boot_params.screen_info.lfb_size = vginfo.total_memory;
227
228	if (vminfo.bpp <= 8)
229		vesa_dac_set_8bits();
230
231	vesa_store_pm_info();
232}
233
234/*
235 * Save EDID information for the kernel; this is invoked, separately,
236 * after mode-setting.
237 */
238void vesa_store_edid(void)
239{
240#ifdef CONFIG_FIRMWARE_EDID
241	struct biosregs ireg, oreg;
242
243	/* Apparently used as a nonsense token... */
244	memset(&boot_params.edid_info, 0x13, sizeof boot_params.edid_info);
245
246	if (vginfo.version < 0x0200)
247		return;		/* EDID requires VBE 2.0+ */
248
249	initregs(&ireg);
250	ireg.ax = 0x4f15;		/* VBE DDC */
251	/* ireg.bx = 0x0000; */		/* Report DDC capabilities */
252	/* ireg.cx = 0;	*/		/* Controller 0 */
253	ireg.es = 0;			/* ES:DI must be 0 by spec */
254	intcall(0x10, &ireg, &oreg);
255
256	if (oreg.ax != 0x004f)
257		return;		/* No EDID */
258
259	/* BH = time in seconds to transfer EDD information */
260	/* BL = DDC level supported */
261
262	ireg.ax = 0x4f15;		/* VBE DDC */
263	ireg.bx = 0x0001;		/* Read EDID */
264	/* ireg.cx = 0; */		/* Controller 0 */
265	/* ireg.dx = 0;	*/		/* EDID block number */
266	ireg.es = ds();
267	ireg.di =(size_t)&boot_params.edid_info; /* (ES:)Pointer to block */
268	intcall(0x10, &ireg, &oreg);
269#endif /* CONFIG_FIRMWARE_EDID */
270}
271
272#endif /* not _WAKEUP */
273
274static __videocard video_vesa =
275{
276	.card_name	= "VESA",
277	.probe		= vesa_probe,
278	.set_mode	= vesa_set_mode,
279	.xmode_first	= VIDEO_FIRST_VESA,
280	.xmode_n	= 0x200,
281};
v6.2
  1// SPDX-License-Identifier: GPL-2.0-only
  2/* -*- linux-c -*- ------------------------------------------------------- *
  3 *
  4 *   Copyright (C) 1991, 1992 Linus Torvalds
  5 *   Copyright 2007 rPath, Inc. - All Rights Reserved
  6 *   Copyright 2009 Intel Corporation; author H. Peter Anvin
  7 *
 
 
 
  8 * ----------------------------------------------------------------------- */
  9
 10/*
 11 * VESA text modes
 12 */
 13
 14#include "boot.h"
 15#include "video.h"
 16#include "vesa.h"
 17#include "string.h"
 18
 19/* VESA information */
 20static struct vesa_general_info vginfo;
 21static struct vesa_mode_info vminfo;
 22
 23static __videocard video_vesa;
 24
 25#ifndef _WAKEUP
 26static void vesa_store_mode_params_graphics(void);
 27#else /* _WAKEUP */
 28static inline void vesa_store_mode_params_graphics(void) {}
 29#endif /* _WAKEUP */
 30
 31static int vesa_probe(void)
 32{
 33	struct biosregs ireg, oreg;
 34	u16 mode;
 35	addr_t mode_ptr;
 36	struct mode_info *mi;
 37	int nmodes = 0;
 38
 39	video_vesa.modes = GET_HEAP(struct mode_info, 0);
 40
 41	initregs(&ireg);
 42	ireg.ax = 0x4f00;
 43	ireg.di = (size_t)&vginfo;
 44	intcall(0x10, &ireg, &oreg);
 45
 46	if (oreg.ax != 0x004f ||
 47	    vginfo.signature != VESA_MAGIC ||
 48	    vginfo.version < 0x0102)
 49		return 0;	/* Not present */
 50
 51	set_fs(vginfo.video_mode_ptr.seg);
 52	mode_ptr = vginfo.video_mode_ptr.off;
 53
 54	while ((mode = rdfs16(mode_ptr)) != 0xffff) {
 55		mode_ptr += 2;
 56
 57		if (!heap_free(sizeof(struct mode_info)))
 58			break;	/* Heap full, can't save mode info */
 59
 60		if (mode & ~0x1ff)
 61			continue;
 62
 63		memset(&vminfo, 0, sizeof(vminfo)); /* Just in case... */
 64
 65		ireg.ax = 0x4f01;
 66		ireg.cx = mode;
 67		ireg.di = (size_t)&vminfo;
 68		intcall(0x10, &ireg, &oreg);
 69
 70		if (oreg.ax != 0x004f)
 71			continue;
 72
 73		if ((vminfo.mode_attr & 0x15) == 0x05) {
 74			/* Text Mode, TTY BIOS supported,
 75			   supported by hardware */
 76			mi = GET_HEAP(struct mode_info, 1);
 77			mi->mode  = mode + VIDEO_FIRST_VESA;
 78			mi->depth = 0; /* text */
 79			mi->x     = vminfo.h_res;
 80			mi->y     = vminfo.v_res;
 81			nmodes++;
 82		} else if ((vminfo.mode_attr & 0x99) == 0x99 &&
 83			   (vminfo.memory_layout == 4 ||
 84			    vminfo.memory_layout == 6) &&
 85			   vminfo.memory_planes == 1) {
 86#ifdef CONFIG_BOOT_VESA_SUPPORT
 87			/* Graphics mode, color, linear frame buffer
 88			   supported.  Only register the mode if
 89			   if framebuffer is configured, however,
 90			   otherwise the user will be left without a screen. */
 91			mi = GET_HEAP(struct mode_info, 1);
 92			mi->mode = mode + VIDEO_FIRST_VESA;
 93			mi->depth = vminfo.bpp;
 94			mi->x = vminfo.h_res;
 95			mi->y = vminfo.v_res;
 96			nmodes++;
 97#endif
 98		}
 99	}
100
101	return nmodes;
102}
103
104static int vesa_set_mode(struct mode_info *mode)
105{
106	struct biosregs ireg, oreg;
107	int is_graphic;
108	u16 vesa_mode = mode->mode - VIDEO_FIRST_VESA;
109
110	memset(&vminfo, 0, sizeof(vminfo)); /* Just in case... */
111
112	initregs(&ireg);
113	ireg.ax = 0x4f01;
114	ireg.cx = vesa_mode;
115	ireg.di = (size_t)&vminfo;
116	intcall(0x10, &ireg, &oreg);
117
118	if (oreg.ax != 0x004f)
119		return -1;
120
121	if ((vminfo.mode_attr & 0x15) == 0x05) {
122		/* It's a supported text mode */
123		is_graphic = 0;
124#ifdef CONFIG_BOOT_VESA_SUPPORT
125	} else if ((vminfo.mode_attr & 0x99) == 0x99) {
126		/* It's a graphics mode with linear frame buffer */
127		is_graphic = 1;
128		vesa_mode |= 0x4000; /* Request linear frame buffer */
129#endif
130	} else {
131		return -1;	/* Invalid mode */
132	}
133
134
135	initregs(&ireg);
136	ireg.ax = 0x4f02;
137	ireg.bx = vesa_mode;
138	intcall(0x10, &ireg, &oreg);
139
140	if (oreg.ax != 0x004f)
141		return -1;
142
143	graphic_mode = is_graphic;
144	if (!is_graphic) {
145		/* Text mode */
146		force_x = mode->x;
147		force_y = mode->y;
148		do_restore = 1;
149	} else {
150		/* Graphics mode */
151		vesa_store_mode_params_graphics();
152	}
153
154	return 0;
155}
156
157
158#ifndef _WAKEUP
159
160/* Switch DAC to 8-bit mode */
161static void vesa_dac_set_8bits(void)
162{
163	struct biosregs ireg, oreg;
164	u8 dac_size = 6;
165
166	/* If possible, switch the DAC to 8-bit mode */
167	if (vginfo.capabilities & 1) {
168		initregs(&ireg);
169		ireg.ax = 0x4f08;
170		ireg.bh = 0x08;
171		intcall(0x10, &ireg, &oreg);
172		if (oreg.ax == 0x004f)
173			dac_size = oreg.bh;
174	}
175
176	/* Set the color sizes to the DAC size, and offsets to 0 */
177	boot_params.screen_info.red_size   = dac_size;
178	boot_params.screen_info.green_size = dac_size;
179	boot_params.screen_info.blue_size  = dac_size;
180	boot_params.screen_info.rsvd_size  = dac_size;
181
182	boot_params.screen_info.red_pos    = 0;
183	boot_params.screen_info.green_pos  = 0;
184	boot_params.screen_info.blue_pos   = 0;
185	boot_params.screen_info.rsvd_pos   = 0;
186}
187
188/* Save the VESA protected mode info */
189static void vesa_store_pm_info(void)
190{
191	struct biosregs ireg, oreg;
192
193	initregs(&ireg);
194	ireg.ax = 0x4f0a;
195	intcall(0x10, &ireg, &oreg);
196
197	if (oreg.ax != 0x004f)
198		return;
199
200	boot_params.screen_info.vesapm_seg = oreg.es;
201	boot_params.screen_info.vesapm_off = oreg.di;
202}
203
204/*
205 * Save video mode parameters for graphics mode
206 */
207static void vesa_store_mode_params_graphics(void)
208{
209	/* Tell the kernel we're in VESA graphics mode */
210	boot_params.screen_info.orig_video_isVGA = VIDEO_TYPE_VLFB;
211
212	/* Mode parameters */
213	boot_params.screen_info.vesa_attributes = vminfo.mode_attr;
214	boot_params.screen_info.lfb_linelength = vminfo.logical_scan;
215	boot_params.screen_info.lfb_width = vminfo.h_res;
216	boot_params.screen_info.lfb_height = vminfo.v_res;
217	boot_params.screen_info.lfb_depth = vminfo.bpp;
218	boot_params.screen_info.pages = vminfo.image_planes;
219	boot_params.screen_info.lfb_base = vminfo.lfb_ptr;
220	memcpy(&boot_params.screen_info.red_size,
221	       &vminfo.rmask, 8);
222
223	/* General parameters */
224	boot_params.screen_info.lfb_size = vginfo.total_memory;
225
226	if (vminfo.bpp <= 8)
227		vesa_dac_set_8bits();
228
229	vesa_store_pm_info();
230}
231
232/*
233 * Save EDID information for the kernel; this is invoked, separately,
234 * after mode-setting.
235 */
236void vesa_store_edid(void)
237{
238#ifdef CONFIG_FIRMWARE_EDID
239	struct biosregs ireg, oreg;
240
241	/* Apparently used as a nonsense token... */
242	memset(&boot_params.edid_info, 0x13, sizeof(boot_params.edid_info));
243
244	if (vginfo.version < 0x0200)
245		return;		/* EDID requires VBE 2.0+ */
246
247	initregs(&ireg);
248	ireg.ax = 0x4f15;		/* VBE DDC */
249	/* ireg.bx = 0x0000; */		/* Report DDC capabilities */
250	/* ireg.cx = 0;	*/		/* Controller 0 */
251	ireg.es = 0;			/* ES:DI must be 0 by spec */
252	intcall(0x10, &ireg, &oreg);
253
254	if (oreg.ax != 0x004f)
255		return;		/* No EDID */
256
257	/* BH = time in seconds to transfer EDD information */
258	/* BL = DDC level supported */
259
260	ireg.ax = 0x4f15;		/* VBE DDC */
261	ireg.bx = 0x0001;		/* Read EDID */
262	/* ireg.cx = 0; */		/* Controller 0 */
263	/* ireg.dx = 0;	*/		/* EDID block number */
264	ireg.es = ds();
265	ireg.di =(size_t)&boot_params.edid_info; /* (ES:)Pointer to block */
266	intcall(0x10, &ireg, &oreg);
267#endif /* CONFIG_FIRMWARE_EDID */
268}
269
270#endif /* not _WAKEUP */
271
272static __videocard video_vesa =
273{
274	.card_name	= "VESA",
275	.probe		= vesa_probe,
276	.set_mode	= vesa_set_mode,
277	.xmode_first	= VIDEO_FIRST_VESA,
278	.xmode_n	= 0x200,
279};