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  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 * Select video mode
 14 */
 15
 16#include "boot.h"
 17#include "video.h"
 18#include "vesa.h"
 19
 20static void store_cursor_position(void)
 21{
 22	struct biosregs ireg, oreg;
 23
 24	initregs(&ireg);
 25	ireg.ah = 0x03;
 26	intcall(0x10, &ireg, &oreg);
 27
 28	boot_params.screen_info.orig_x = oreg.dl;
 29	boot_params.screen_info.orig_y = oreg.dh;
 30
 31	if (oreg.ch & 0x20)
 32		boot_params.screen_info.flags |= VIDEO_FLAGS_NOCURSOR;
 33
 34	if ((oreg.ch & 0x1f) > (oreg.cl & 0x1f))
 35		boot_params.screen_info.flags |= VIDEO_FLAGS_NOCURSOR;
 36}
 37
 38static void store_video_mode(void)
 39{
 40	struct biosregs ireg, oreg;
 41
 42	/* N.B.: the saving of the video page here is a bit silly,
 43	   since we pretty much assume page 0 everywhere. */
 44	initregs(&ireg);
 45	ireg.ah = 0x0f;
 46	intcall(0x10, &ireg, &oreg);
 47
 48	/* Not all BIOSes are clean with respect to the top bit */
 49	boot_params.screen_info.orig_video_mode = oreg.al & 0x7f;
 50	boot_params.screen_info.orig_video_page = oreg.bh;
 51}
 52
 53/*
 54 * Store the video mode parameters for later usage by the kernel.
 55 * This is done by asking the BIOS except for the rows/columns
 56 * parameters in the default 80x25 mode -- these are set directly,
 57 * because some very obscure BIOSes supply insane values.
 58 */
 59static void store_mode_params(void)
 60{
 61	u16 font_size;
 62	int x, y;
 63
 64	/* For graphics mode, it is up to the mode-setting driver
 65	   (currently only video-vesa.c) to store the parameters */
 66	if (graphic_mode)
 67		return;
 68
 69	store_cursor_position();
 70	store_video_mode();
 71
 72	if (boot_params.screen_info.orig_video_mode == 0x07) {
 73		/* MDA, HGC, or VGA in monochrome mode */
 74		video_segment = 0xb000;
 75	} else {
 76		/* CGA, EGA, VGA and so forth */
 77		video_segment = 0xb800;
 78	}
 79
 80	set_fs(0);
 81	font_size = rdfs16(0x485); /* Font size, BIOS area */
 82	boot_params.screen_info.orig_video_points = font_size;
 83
 84	x = rdfs16(0x44a);
 85	y = (adapter == ADAPTER_CGA) ? 25 : rdfs8(0x484)+1;
 86
 87	if (force_x)
 88		x = force_x;
 89	if (force_y)
 90		y = force_y;
 91
 92	boot_params.screen_info.orig_video_cols  = x;
 93	boot_params.screen_info.orig_video_lines = y;
 94}
 95
 96static unsigned int get_entry(void)
 97{
 98	char entry_buf[4];
 99	int i, len = 0;
100	int key;
101	unsigned int v;
102
103	do {
104		key = getchar();
105
106		if (key == '\b') {
107			if (len > 0) {
108				puts("\b \b");
109				len--;
110			}
111		} else if ((key >= '0' && key <= '9') ||
112			   (key >= 'A' && key <= 'Z') ||
113			   (key >= 'a' && key <= 'z')) {
114			if (len < sizeof entry_buf) {
115				entry_buf[len++] = key;
116				putchar(key);
117			}
118		}
119	} while (key != '\r');
120	putchar('\n');
121
122	if (len == 0)
123		return VIDEO_CURRENT_MODE; /* Default */
124
125	v = 0;
126	for (i = 0; i < len; i++) {
127		v <<= 4;
128		key = entry_buf[i] | 0x20;
129		v += (key > '9') ? key-'a'+10 : key-'0';
130	}
131
132	return v;
133}
134
135static void display_menu(void)
136{
137	struct card_info *card;
138	struct mode_info *mi;
139	char ch;
140	int i;
141	int nmodes;
142	int modes_per_line;
143	int col;
144
145	nmodes = 0;
146	for (card = video_cards; card < video_cards_end; card++)
147		nmodes += card->nmodes;
148
149	modes_per_line = 1;
150	if (nmodes >= 20)
151		modes_per_line = 3;
152
153	for (col = 0; col < modes_per_line; col++)
154		puts("Mode: Resolution:  Type: ");
155	putchar('\n');
156
157	col = 0;
158	ch = '0';
159	for (card = video_cards; card < video_cards_end; card++) {
160		mi = card->modes;
161		for (i = 0; i < card->nmodes; i++, mi++) {
162			char resbuf[32];
163			int visible = mi->x && mi->y;
164			u16 mode_id = mi->mode ? mi->mode :
165				(mi->y << 8)+mi->x;
166
167			if (!visible)
168				continue; /* Hidden mode */
169
170			if (mi->depth)
171				sprintf(resbuf, "%dx%d", mi->y, mi->depth);
172			else
173				sprintf(resbuf, "%d", mi->y);
174
175			printf("%c %03X %4dx%-7s %-6s",
176			       ch, mode_id, mi->x, resbuf, card->card_name);
177			col++;
178			if (col >= modes_per_line) {
179				putchar('\n');
180				col = 0;
181			}
182
183			if (ch == '9')
184				ch = 'a';
185			else if (ch == 'z' || ch == ' ')
186				ch = ' '; /* Out of keys... */
187			else
188				ch++;
189		}
190	}
191	if (col)
192		putchar('\n');
193}
194
195#define H(x)	((x)-'a'+10)
196#define SCAN	((H('s')<<12)+(H('c')<<8)+(H('a')<<4)+H('n'))
197
198static unsigned int mode_menu(void)
199{
200	int key;
201	unsigned int sel;
202
203	puts("Press <ENTER> to see video modes available, "
204	     "<SPACE> to continue, or wait 30 sec\n");
205
206	kbd_flush();
207	while (1) {
208		key = getchar_timeout();
209		if (key == ' ' || key == 0)
210			return VIDEO_CURRENT_MODE; /* Default */
211		if (key == '\r')
212			break;
213		putchar('\a');	/* Beep! */
214	}
215
216
217	for (;;) {
218		display_menu();
219
220		puts("Enter a video mode or \"scan\" to scan for "
221		     "additional modes: ");
222		sel = get_entry();
223		if (sel != SCAN)
224			return sel;
225
226		probe_cards(1);
227	}
228}
229
230/* Save screen content to the heap */
231static struct saved_screen {
232	int x, y;
233	int curx, cury;
234	u16 *data;
235} saved;
236
237static void save_screen(void)
238{
239	/* Should be called after store_mode_params() */
240	saved.x = boot_params.screen_info.orig_video_cols;
241	saved.y = boot_params.screen_info.orig_video_lines;
242	saved.curx = boot_params.screen_info.orig_x;
243	saved.cury = boot_params.screen_info.orig_y;
244
245	if (!heap_free(saved.x*saved.y*sizeof(u16)+512))
246		return;		/* Not enough heap to save the screen */
247
248	saved.data = GET_HEAP(u16, saved.x*saved.y);
249
250	set_fs(video_segment);
251	copy_from_fs(saved.data, 0, saved.x*saved.y*sizeof(u16));
252}
253
254static void restore_screen(void)
255{
256	/* Should be called after store_mode_params() */
257	int xs = boot_params.screen_info.orig_video_cols;
258	int ys = boot_params.screen_info.orig_video_lines;
259	int y;
260	addr_t dst = 0;
261	u16 *src = saved.data;
262	struct biosregs ireg;
263
264	if (graphic_mode)
265		return;		/* Can't restore onto a graphic mode */
266
267	if (!src)
268		return;		/* No saved screen contents */
269
270	/* Restore screen contents */
271
272	set_fs(video_segment);
273	for (y = 0; y < ys; y++) {
274		int npad;
275
276		if (y < saved.y) {
277			int copy = (xs < saved.x) ? xs : saved.x;
278			copy_to_fs(dst, src, copy*sizeof(u16));
279			dst += copy*sizeof(u16);
280			src += saved.x;
281			npad = (xs < saved.x) ? 0 : xs-saved.x;
282		} else {
283			npad = xs;
284		}
285
286		/* Writes "npad" blank characters to
287		   video_segment:dst and advances dst */
288		asm volatile("pushw %%es ; "
289			     "movw %2,%%es ; "
290			     "shrw %%cx ; "
291			     "jnc 1f ; "
292			     "stosw \n\t"
293			     "1: rep;stosl ; "
294			     "popw %%es"
295			     : "+D" (dst), "+c" (npad)
296			     : "bdS" (video_segment),
297			       "a" (0x07200720));
298	}
299
300	/* Restore cursor position */
301	if (saved.curx >= xs)
302		saved.curx = xs-1;
303	if (saved.cury >= ys)
304		saved.cury = ys-1;
305
306	initregs(&ireg);
307	ireg.ah = 0x02;		/* Set cursor position */
308	ireg.dh = saved.cury;
309	ireg.dl = saved.curx;
310	intcall(0x10, &ireg, NULL);
311
312	store_cursor_position();
313}
314
315void set_video(void)
316{
317	u16 mode = boot_params.hdr.vid_mode;
318
319	RESET_HEAP();
320
321	store_mode_params();
322	save_screen();
323	probe_cards(0);
324
325	for (;;) {
326		if (mode == ASK_VGA)
327			mode = mode_menu();
328
329		if (!set_mode(mode))
330			break;
331
332		printf("Undefined video mode number: %x\n", mode);
333		mode = ASK_VGA;
334	}
335	boot_params.hdr.vid_mode = mode;
336	vesa_store_edid();
337	store_mode_params();
338
339	if (do_restore)
340		restore_screen();
341}
  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 * Select video mode
 12 */
 13
 14#include <uapi/asm/boot.h>
 15
 16#include "boot.h"
 17#include "video.h"
 18#include "vesa.h"
 19
 20static u16 video_segment;
 21
 22static void store_cursor_position(void)
 23{
 24	struct biosregs ireg, oreg;
 25
 26	initregs(&ireg);
 27	ireg.ah = 0x03;
 28	intcall(0x10, &ireg, &oreg);
 29
 30	boot_params.screen_info.orig_x = oreg.dl;
 31	boot_params.screen_info.orig_y = oreg.dh;
 32
 33	if (oreg.ch & 0x20)
 34		boot_params.screen_info.flags |= VIDEO_FLAGS_NOCURSOR;
 35
 36	if ((oreg.ch & 0x1f) > (oreg.cl & 0x1f))
 37		boot_params.screen_info.flags |= VIDEO_FLAGS_NOCURSOR;
 38}
 39
 40static void store_video_mode(void)
 41{
 42	struct biosregs ireg, oreg;
 43
 44	/* N.B.: the saving of the video page here is a bit silly,
 45	   since we pretty much assume page 0 everywhere. */
 46	initregs(&ireg);
 47	ireg.ah = 0x0f;
 48	intcall(0x10, &ireg, &oreg);
 49
 50	/* Not all BIOSes are clean with respect to the top bit */
 51	boot_params.screen_info.orig_video_mode = oreg.al & 0x7f;
 52	boot_params.screen_info.orig_video_page = oreg.bh;
 53}
 54
 55/*
 56 * Store the video mode parameters for later usage by the kernel.
 57 * This is done by asking the BIOS except for the rows/columns
 58 * parameters in the default 80x25 mode -- these are set directly,
 59 * because some very obscure BIOSes supply insane values.
 60 */
 61static void store_mode_params(void)
 62{
 63	u16 font_size;
 64	int x, y;
 65
 66	/* For graphics mode, it is up to the mode-setting driver
 67	   (currently only video-vesa.c) to store the parameters */
 68	if (graphic_mode)
 69		return;
 70
 71	store_cursor_position();
 72	store_video_mode();
 73
 74	if (boot_params.screen_info.orig_video_mode == 0x07) {
 75		/* MDA, HGC, or VGA in monochrome mode */
 76		video_segment = 0xb000;
 77	} else {
 78		/* CGA, EGA, VGA and so forth */
 79		video_segment = 0xb800;
 80	}
 81
 82	set_fs(0);
 83	font_size = rdfs16(0x485); /* Font size, BIOS area */
 84	boot_params.screen_info.orig_video_points = font_size;
 85
 86	x = rdfs16(0x44a);
 87	y = (adapter == ADAPTER_CGA) ? 25 : rdfs8(0x484)+1;
 88
 89	if (force_x)
 90		x = force_x;
 91	if (force_y)
 92		y = force_y;
 93
 94	boot_params.screen_info.orig_video_cols  = x;
 95	boot_params.screen_info.orig_video_lines = y;
 96}
 97
 98static unsigned int get_entry(void)
 99{
100	char entry_buf[4];
101	int i, len = 0;
102	int key;
103	unsigned int v;
104
105	do {
106		key = getchar();
107
108		if (key == '\b') {
109			if (len > 0) {
110				puts("\b \b");
111				len--;
112			}
113		} else if ((key >= '0' && key <= '9') ||
114			   (key >= 'A' && key <= 'Z') ||
115			   (key >= 'a' && key <= 'z')) {
116			if (len < sizeof(entry_buf)) {
117				entry_buf[len++] = key;
118				putchar(key);
119			}
120		}
121	} while (key != '\r');
122	putchar('\n');
123
124	if (len == 0)
125		return VIDEO_CURRENT_MODE; /* Default */
126
127	v = 0;
128	for (i = 0; i < len; i++) {
129		v <<= 4;
130		key = entry_buf[i] | 0x20;
131		v += (key > '9') ? key-'a'+10 : key-'0';
132	}
133
134	return v;
135}
136
137static void display_menu(void)
138{
139	struct card_info *card;
140	struct mode_info *mi;
141	char ch;
142	int i;
143	int nmodes;
144	int modes_per_line;
145	int col;
146
147	nmodes = 0;
148	for (card = video_cards; card < video_cards_end; card++)
149		nmodes += card->nmodes;
150
151	modes_per_line = 1;
152	if (nmodes >= 20)
153		modes_per_line = 3;
154
155	for (col = 0; col < modes_per_line; col++)
156		puts("Mode: Resolution:  Type: ");
157	putchar('\n');
158
159	col = 0;
160	ch = '0';
161	for (card = video_cards; card < video_cards_end; card++) {
162		mi = card->modes;
163		for (i = 0; i < card->nmodes; i++, mi++) {
164			char resbuf[32];
165			int visible = mi->x && mi->y;
166			u16 mode_id = mi->mode ? mi->mode :
167				(mi->y << 8)+mi->x;
168
169			if (!visible)
170				continue; /* Hidden mode */
171
172			if (mi->depth)
173				sprintf(resbuf, "%dx%d", mi->y, mi->depth);
174			else
175				sprintf(resbuf, "%d", mi->y);
176
177			printf("%c %03X %4dx%-7s %-6s",
178			       ch, mode_id, mi->x, resbuf, card->card_name);
179			col++;
180			if (col >= modes_per_line) {
181				putchar('\n');
182				col = 0;
183			}
184
185			if (ch == '9')
186				ch = 'a';
187			else if (ch == 'z' || ch == ' ')
188				ch = ' '; /* Out of keys... */
189			else
190				ch++;
191		}
192	}
193	if (col)
194		putchar('\n');
195}
196
197#define H(x)	((x)-'a'+10)
198#define SCAN	((H('s')<<12)+(H('c')<<8)+(H('a')<<4)+H('n'))
199
200static unsigned int mode_menu(void)
201{
202	int key;
203	unsigned int sel;
204
205	puts("Press <ENTER> to see video modes available, "
206	     "<SPACE> to continue, or wait 30 sec\n");
207
208	kbd_flush();
209	while (1) {
210		key = getchar_timeout();
211		if (key == ' ' || key == 0)
212			return VIDEO_CURRENT_MODE; /* Default */
213		if (key == '\r')
214			break;
215		putchar('\a');	/* Beep! */
216	}
217
218
219	for (;;) {
220		display_menu();
221
222		puts("Enter a video mode or \"scan\" to scan for "
223		     "additional modes: ");
224		sel = get_entry();
225		if (sel != SCAN)
226			return sel;
227
228		probe_cards(1);
229	}
230}
231
232/* Save screen content to the heap */
233static struct saved_screen {
234	int x, y;
235	int curx, cury;
236	u16 *data;
237} saved;
238
239static void save_screen(void)
240{
241	/* Should be called after store_mode_params() */
242	saved.x = boot_params.screen_info.orig_video_cols;
243	saved.y = boot_params.screen_info.orig_video_lines;
244	saved.curx = boot_params.screen_info.orig_x;
245	saved.cury = boot_params.screen_info.orig_y;
246
247	if (!heap_free(saved.x*saved.y*sizeof(u16)+512))
248		return;		/* Not enough heap to save the screen */
249
250	saved.data = GET_HEAP(u16, saved.x*saved.y);
251
252	set_fs(video_segment);
253	copy_from_fs(saved.data, 0, saved.x*saved.y*sizeof(u16));
254}
255
256static void restore_screen(void)
257{
258	/* Should be called after store_mode_params() */
259	int xs = boot_params.screen_info.orig_video_cols;
260	int ys = boot_params.screen_info.orig_video_lines;
261	int y;
262	addr_t dst = 0;
263	u16 *src = saved.data;
264	struct biosregs ireg;
265
266	if (graphic_mode)
267		return;		/* Can't restore onto a graphic mode */
268
269	if (!src)
270		return;		/* No saved screen contents */
271
272	/* Restore screen contents */
273
274	set_fs(video_segment);
275	for (y = 0; y < ys; y++) {
276		int npad;
277
278		if (y < saved.y) {
279			int copy = (xs < saved.x) ? xs : saved.x;
280			copy_to_fs(dst, src, copy*sizeof(u16));
281			dst += copy*sizeof(u16);
282			src += saved.x;
283			npad = (xs < saved.x) ? 0 : xs-saved.x;
284		} else {
285			npad = xs;
286		}
287
288		/* Writes "npad" blank characters to
289		   video_segment:dst and advances dst */
290		asm volatile("pushw %%es ; "
291			     "movw %2,%%es ; "
292			     "shrw %%cx ; "
293			     "jnc 1f ; "
294			     "stosw \n\t"
295			     "1: rep;stosl ; "
296			     "popw %%es"
297			     : "+D" (dst), "+c" (npad)
298			     : "bdS" (video_segment),
299			       "a" (0x07200720));
300	}
301
302	/* Restore cursor position */
303	if (saved.curx >= xs)
304		saved.curx = xs-1;
305	if (saved.cury >= ys)
306		saved.cury = ys-1;
307
308	initregs(&ireg);
309	ireg.ah = 0x02;		/* Set cursor position */
310	ireg.dh = saved.cury;
311	ireg.dl = saved.curx;
312	intcall(0x10, &ireg, NULL);
313
314	store_cursor_position();
315}
316
317void set_video(void)
318{
319	u16 mode = boot_params.hdr.vid_mode;
320
321	RESET_HEAP();
322
323	store_mode_params();
324	save_screen();
325	probe_cards(0);
326
327	for (;;) {
328		if (mode == ASK_VGA)
329			mode = mode_menu();
330
331		if (!set_mode(mode))
332			break;
333
334		printf("Undefined video mode number: %x\n", mode);
335		mode = ASK_VGA;
336	}
337	boot_params.hdr.vid_mode = mode;
338	vesa_store_edid();
339	store_mode_params();
340
341	if (do_restore)
342		restore_screen();
343}