1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  *  EFI application console interface
4  *
5  *  Copyright (c) 2016 Alexander Graf
6  */
7 
8 #define LOG_CATEGORY LOGC_EFI
9 
10 #include <ansi.h>
11 #include <common.h>
12 #include <charset.h>
13 #include <malloc.h>
14 #include <time.h>
15 #include <dm/device.h>
16 #include <efi_loader.h>
17 #include <env.h>
18 #include <log.h>
19 #include <stdio_dev.h>
20 #include <video_console.h>
21 #include <linux/delay.h>
22 
23 #define EFI_COUT_MODE_2 2
24 #define EFI_MAX_COUT_MODE 3
25 
26 struct cout_mode {
27 	unsigned long columns;
28 	unsigned long rows;
29 	int present;
30 };
31 
32 __maybe_unused static struct efi_object uart_obj;
33 
34 static struct cout_mode efi_cout_modes[] = {
35 	/* EFI Mode 0 is 80x25 and always present */
36 	{
37 		.columns = 80,
38 		.rows = 25,
39 		.present = 1,
40 	},
41 	/* EFI Mode 1 is always 80x50 */
42 	{
43 		.columns = 80,
44 		.rows = 50,
45 		.present = 0,
46 	},
47 	/* Value are unknown until we query the console */
48 	{
49 		.columns = 0,
50 		.rows = 0,
51 		.present = 0,
52 	},
53 };
54 
55 const efi_guid_t efi_guid_text_input_ex_protocol =
56 			EFI_SIMPLE_TEXT_INPUT_EX_PROTOCOL_GUID;
57 const efi_guid_t efi_guid_text_input_protocol =
58 			EFI_SIMPLE_TEXT_INPUT_PROTOCOL_GUID;
59 const efi_guid_t efi_guid_text_output_protocol =
60 			EFI_SIMPLE_TEXT_OUTPUT_PROTOCOL_GUID;
61 
62 #define cESC '\x1b'
63 #define ESC "\x1b"
64 
65 /*
66  * efi_con_mode - mode information of the Simple Text Output Protocol
67  *
68  * Use safe settings before efi_setup_console_size() is called.
69  * By default enable only the 80x25 mode which must always exist.
70  */
71 static struct simple_text_output_mode efi_con_mode = {
72 	.max_mode = 1,
73 	.mode = 0,
74 	.attribute = 0,
75 	.cursor_column = 0,
76 	.cursor_row = 0,
77 	.cursor_visible = 1,
78 };
79 
80 /**
81  * term_get_char() - read a character from the console
82  *
83  * Wait for up to 100 ms to read a character from the console.
84  *
85  * @c:		pointer to the buffer to receive the character
86  * Return:	0 on success, 1 otherwise
87  */
term_get_char(s32 * c)88 static int term_get_char(s32 *c)
89 {
90 	u64 timeout;
91 
92 	/* Wait up to 100 ms for a character */
93 	timeout = timer_get_us() + 100000;
94 
95 	while (!tstc())
96 		if (timer_get_us() > timeout)
97 			return 1;
98 
99 	*c = getchar();
100 	return 0;
101 }
102 
103 /**
104  * Receive and parse a reply from the terminal.
105  *
106  * @n:		array of return values
107  * @num:	number of return values expected
108  * @end_char:	character indicating end of terminal message
109  * Return:	non-zero indicates error
110  */
term_read_reply(int * n,int num,char end_char)111 static int term_read_reply(int *n, int num, char end_char)
112 {
113 	s32 c;
114 	int i = 0;
115 
116 	if (term_get_char(&c) || c != cESC)
117 		return -1;
118 
119 	if (term_get_char(&c) || c != '[')
120 		return -1;
121 
122 	n[0] = 0;
123 	while (1) {
124 		if (!term_get_char(&c)) {
125 			if (c == ';') {
126 				i++;
127 				if (i >= num)
128 					return -1;
129 				n[i] = 0;
130 				continue;
131 			} else if (c == end_char) {
132 				break;
133 			} else if (c > '9' || c < '0') {
134 				return -1;
135 			}
136 
137 			/* Read one more decimal position */
138 			n[i] *= 10;
139 			n[i] += c - '0';
140 		} else {
141 			return -1;
142 		}
143 	}
144 	if (i != num - 1)
145 		return -1;
146 
147 	return 0;
148 }
149 
150 /**
151  * efi_cout_output_string() - write Unicode string to console
152  *
153  * This function implements the OutputString service of the simple text output
154  * protocol. See the Unified Extensible Firmware Interface (UEFI) specification
155  * for details.
156  *
157  * @this:	simple text output protocol
158  * @string:	u16 string
159  * Return:	status code
160  */
efi_cout_output_string(struct efi_simple_text_output_protocol * this,const u16 * string)161 static efi_status_t EFIAPI efi_cout_output_string(
162 			struct efi_simple_text_output_protocol *this,
163 			const u16 *string)
164 {
165 	struct simple_text_output_mode *con = &efi_con_mode;
166 	struct cout_mode *mode = &efi_cout_modes[con->mode];
167 	char *buf, *pos;
168 	const u16 *p;
169 	efi_status_t ret = EFI_SUCCESS;
170 
171 	EFI_ENTRY("%p, %p", this, string);
172 
173 	if (!this || !string) {
174 		ret = EFI_INVALID_PARAMETER;
175 		goto out;
176 	}
177 
178 	buf = malloc(utf16_utf8_strlen(string) + 1);
179 	if (!buf) {
180 		ret = EFI_OUT_OF_RESOURCES;
181 		goto out;
182 	}
183 	pos = buf;
184 	utf16_utf8_strcpy(&pos, string);
185 	fputs(stdout, buf);
186 	free(buf);
187 
188 	/*
189 	 * Update the cursor position.
190 	 *
191 	 * The UEFI spec provides advance rules for U+0000, U+0008, U+000A,
192 	 * and U000D. All other control characters are ignored. Any non-control
193 	 * character increase the column by one.
194 	 */
195 	for (p = string; *p; ++p) {
196 		switch (*p) {
197 		case '\b':	/* U+0008, backspace */
198 			if (con->cursor_column)
199 				con->cursor_column--;
200 			break;
201 		case '\n':	/* U+000A, newline */
202 			con->cursor_column = 0;
203 			con->cursor_row++;
204 			break;
205 		case '\r':	/* U+000D, carriage-return */
206 			con->cursor_column = 0;
207 			break;
208 		case 0xd800 ... 0xdbff:
209 			/*
210 			 * Ignore high surrogates, we do not want to count a
211 			 * Unicode character twice.
212 			 */
213 			break;
214 		default:
215 			/* Exclude control codes */
216 			if (*p > 0x1f)
217 				con->cursor_column++;
218 			break;
219 		}
220 		if (con->cursor_column >= mode->columns) {
221 			con->cursor_column = 0;
222 			con->cursor_row++;
223 		}
224 		/*
225 		 * When we exceed the row count the terminal will scroll up one
226 		 * line. We have to adjust the cursor position.
227 		 */
228 		if (con->cursor_row >= mode->rows && con->cursor_row)
229 			con->cursor_row--;
230 	}
231 
232 out:
233 	return EFI_EXIT(ret);
234 }
235 
236 /**
237  * efi_cout_test_string() - test writing Unicode string to console
238  *
239  * This function implements the TestString service of the simple text output
240  * protocol. See the Unified Extensible Firmware Interface (UEFI) specification
241  * for details.
242  *
243  * As in OutputString we simply convert UTF-16 to UTF-8 there are no unsupported
244  * code points and we can always return EFI_SUCCESS.
245  *
246  * @this:	simple text output protocol
247  * @string:	u16 string
248  * Return:	status code
249  */
efi_cout_test_string(struct efi_simple_text_output_protocol * this,const u16 * string)250 static efi_status_t EFIAPI efi_cout_test_string(
251 			struct efi_simple_text_output_protocol *this,
252 			const u16 *string)
253 {
254 	EFI_ENTRY("%p, %p", this, string);
255 	return EFI_EXIT(EFI_SUCCESS);
256 }
257 
258 /**
259  * cout_mode_matches() - check if mode has given terminal size
260  *
261  * @mode:	text mode
262  * @rows:	number of rows
263  * @cols:	number of columns
264  * Return:	true if number of rows and columns matches the mode and
265  *		the mode is present
266  */
cout_mode_matches(struct cout_mode * mode,int rows,int cols)267 static bool cout_mode_matches(struct cout_mode *mode, int rows, int cols)
268 {
269 	if (!mode->present)
270 		return false;
271 
272 	return (mode->rows == rows) && (mode->columns == cols);
273 }
274 
275 /**
276  * query_console_serial() - query serial console size
277  *
278  * When using a serial console or the net console we can only devise the
279  * terminal size by querying the terminal using ECMA-48 control sequences.
280  *
281  * @rows:	pointer to return number of rows
282  * @cols:	pointer to return number of columns
283  * Returns:	0 on success
284  */
query_console_serial(int * rows,int * cols)285 static int query_console_serial(int *rows, int *cols)
286 {
287 	int ret = 0;
288 	int n[2];
289 
290 	/* Empty input buffer */
291 	while (tstc())
292 		getchar();
293 
294 	/*
295 	 * Not all terminals understand CSI [18t for querying the console size.
296 	 * We should adhere to escape sequences documented in the console_codes
297 	 * man page and the ECMA-48 standard.
298 	 *
299 	 * So here we follow a different approach. We position the cursor to the
300 	 * bottom right and query its position. Before leaving the function we
301 	 * restore the original cursor position.
302 	 */
303 	printf(ESC "7"		/* Save cursor position */
304 	       ESC "[r"		/* Set scrolling region to full window */
305 	       ESC "[999;999H"	/* Move to bottom right corner */
306 	       ESC "[6n");	/* Query cursor position */
307 
308 	/* Read {rows,cols} */
309 	if (term_read_reply(n, 2, 'R')) {
310 		ret = 1;
311 		goto out;
312 	}
313 
314 	*cols = n[1];
315 	*rows = n[0];
316 out:
317 	printf(ESC "8");	/* Restore cursor position */
318 	return ret;
319 }
320 
321 /**
322  * query_vidconsole() - query video console size
323  *
324  *
325  * @rows:	pointer to return number of rows
326  * @cols:	pointer to return number of columns
327  * Returns:	0 on success
328  */
query_vidconsole(int * rows,int * cols)329 static int __maybe_unused query_vidconsole(int *rows, int *cols)
330 {
331 	const char *stdout_name = env_get("stdout");
332 	struct stdio_dev *stdout_dev;
333 	struct udevice *dev;
334 	struct vidconsole_priv *priv;
335 
336 	if (!stdout_name || strncmp(stdout_name, "vidconsole", 10))
337 		return -ENODEV;
338 	stdout_dev = stdio_get_by_name("vidconsole");
339 	if (!stdout_dev)
340 		return -ENODEV;
341 	dev = stdout_dev->priv;
342 	if (!dev)
343 		return -ENODEV;
344 	priv = dev_get_uclass_priv(dev);
345 	if (!priv)
346 		return -ENODEV;
347 	*rows = priv->rows;
348 	*cols = priv->cols;
349 	return 0;
350 }
351 
352 /**
353  * efi_setup_console_size() - update the mode table.
354  *
355  * By default the only mode available is 80x25. If the console has at least 50
356  * lines, enable mode 80x50. If we can query the console size and it is neither
357  * 80x25 nor 80x50, set it as an additional mode.
358  */
efi_setup_console_size(void)359 void efi_setup_console_size(void)
360 {
361 	int rows = 25, cols = 80;
362 	int ret = -ENODEV;
363 
364 	if (IS_ENABLED(CONFIG_VIDEO))
365 		ret = query_vidconsole(&rows, &cols);
366 	if (ret)
367 		ret = query_console_serial(&rows, &cols);
368 	if (ret)
369 		return;
370 
371 	log_debug("Console size %dx%d\n", rows, cols);
372 
373 	/* Test if we can have Mode 1 */
374 	if (cols >= 80 && rows >= 50) {
375 		efi_cout_modes[1].present = 1;
376 		efi_con_mode.max_mode = 2;
377 	}
378 
379 	/*
380 	 * Install our mode as mode 2 if it is different
381 	 * than mode 0 or 1 and set it as the currently selected mode
382 	 */
383 	if (!cout_mode_matches(&efi_cout_modes[0], rows, cols) &&
384 	    !cout_mode_matches(&efi_cout_modes[1], rows, cols)) {
385 		efi_cout_modes[EFI_COUT_MODE_2].columns = cols;
386 		efi_cout_modes[EFI_COUT_MODE_2].rows = rows;
387 		efi_cout_modes[EFI_COUT_MODE_2].present = 1;
388 		efi_con_mode.max_mode = EFI_MAX_COUT_MODE;
389 		efi_con_mode.mode = EFI_COUT_MODE_2;
390 	}
391 }
392 
393 /**
394  * efi_cout_query_mode() - get terminal size for a text mode
395  *
396  * This function implements the QueryMode service of the simple text output
397  * protocol. See the Unified Extensible Firmware Interface (UEFI) specification
398  * for details.
399  *
400  * @this:		simple text output protocol
401  * @mode_number:	mode number to retrieve information on
402  * @columns:		number of columns
403  * @rows:		number of rows
404  * Return:		status code
405  */
efi_cout_query_mode(struct efi_simple_text_output_protocol * this,unsigned long mode_number,unsigned long * columns,unsigned long * rows)406 static efi_status_t EFIAPI efi_cout_query_mode(
407 			struct efi_simple_text_output_protocol *this,
408 			unsigned long mode_number, unsigned long *columns,
409 			unsigned long *rows)
410 {
411 	EFI_ENTRY("%p, %ld, %p, %p", this, mode_number, columns, rows);
412 
413 	if (mode_number >= efi_con_mode.max_mode)
414 		return EFI_EXIT(EFI_UNSUPPORTED);
415 
416 	if (efi_cout_modes[mode_number].present != 1)
417 		return EFI_EXIT(EFI_UNSUPPORTED);
418 
419 	if (columns)
420 		*columns = efi_cout_modes[mode_number].columns;
421 	if (rows)
422 		*rows = efi_cout_modes[mode_number].rows;
423 
424 	return EFI_EXIT(EFI_SUCCESS);
425 }
426 
427 static const struct {
428 	unsigned int fg;
429 	unsigned int bg;
430 } color[] = {
431 	{ 30, 40 },     /* 0: black */
432 	{ 34, 44 },     /* 1: blue */
433 	{ 32, 42 },     /* 2: green */
434 	{ 36, 46 },     /* 3: cyan */
435 	{ 31, 41 },     /* 4: red */
436 	{ 35, 45 },     /* 5: magenta */
437 	{ 33, 43 },     /* 6: brown, map to yellow as EDK2 does*/
438 	{ 37, 47 },     /* 7: light gray, map to white */
439 };
440 
441 /**
442  * efi_cout_set_attribute() - set fore- and background color
443  *
444  * This function implements the SetAttribute service of the simple text output
445  * protocol. See the Unified Extensible Firmware Interface (UEFI) specification
446  * for details.
447  *
448  * @this:	simple text output protocol
449  * @attribute:	foreground color - bits 0-3, background color - bits 4-6
450  * Return:	status code
451  */
efi_cout_set_attribute(struct efi_simple_text_output_protocol * this,unsigned long attribute)452 static efi_status_t EFIAPI efi_cout_set_attribute(
453 			struct efi_simple_text_output_protocol *this,
454 			unsigned long attribute)
455 {
456 	unsigned int bold = EFI_ATTR_BOLD(attribute);
457 	unsigned int fg = EFI_ATTR_FG(attribute);
458 	unsigned int bg = EFI_ATTR_BG(attribute);
459 
460 	EFI_ENTRY("%p, %lx", this, attribute);
461 
462 	efi_con_mode.attribute = attribute;
463 	if (attribute)
464 		printf(ESC"[%u;%u;%um", bold, color[fg].fg, color[bg].bg);
465 	else
466 		printf(ESC"[0;37;40m");
467 
468 	return EFI_EXIT(EFI_SUCCESS);
469 }
470 
471 /**
472  * efi_clear_screen() - clear screen
473  */
efi_clear_screen(void)474 static void efi_clear_screen(void)
475 {
476 	if (CONFIG_IS_ENABLED(EFI_SCROLL_ON_CLEAR_SCREEN)) {
477 		unsigned int row, screen_rows, screen_columns;
478 
479 		/* Avoid overwriting previous outputs on streaming consoles */
480 		screen_rows = efi_cout_modes[efi_con_mode.mode].rows;
481 		screen_columns = efi_cout_modes[efi_con_mode.mode].columns;
482 		printf(ESC "[%u;%uH", screen_rows, screen_columns);
483 		for (row = 1; row < screen_rows; row++)
484 			printf("\n");
485 	}
486 
487 	/*
488 	 * The Linux console wants both a clear and a home command. The video
489 	 * uclass does not support <ESC>[H without coordinates, yet.
490 	 */
491 	printf(ESC "[2J" ESC "[1;1H");
492 	efi_con_mode.cursor_column = 0;
493 	efi_con_mode.cursor_row = 0;
494 }
495 
496 /**
497  * efi_cout_clear_screen() - clear screen
498  *
499  * This function implements the ClearScreen service of the simple text output
500  * protocol. See the Unified Extensible Firmware Interface (UEFI) specification
501  * for details.
502  *
503  * @this:	pointer to the protocol instance
504  * Return:	status code
505  */
efi_cout_clear_screen(struct efi_simple_text_output_protocol * this)506 static efi_status_t EFIAPI efi_cout_clear_screen(
507 			struct efi_simple_text_output_protocol *this)
508 {
509 	EFI_ENTRY("%p", this);
510 
511 	/* Set default colors if not done yet */
512 	if (efi_con_mode.attribute == 0) {
513 		efi_con_mode.attribute = 0x07;
514 		printf(ESC "[0;37;40m");
515 	}
516 
517 	efi_clear_screen();
518 
519 	return EFI_EXIT(EFI_SUCCESS);
520 }
521 
522 /**
523  * efi_cout_clear_set_mode() - set text model
524  *
525  * This function implements the SetMode service of the simple text output
526  * protocol. See the Unified Extensible Firmware  Interface (UEFI) specification
527  * for details.
528  *
529  * @this:		pointer to the protocol instance
530  * @mode_number:	number of the text mode to set
531  * Return:		status code
532  */
efi_cout_set_mode(struct efi_simple_text_output_protocol * this,unsigned long mode_number)533 static efi_status_t EFIAPI efi_cout_set_mode(
534 			struct efi_simple_text_output_protocol *this,
535 			unsigned long mode_number)
536 {
537 	EFI_ENTRY("%p, %ld", this, mode_number);
538 
539 	if (mode_number >= efi_con_mode.max_mode)
540 		return EFI_EXIT(EFI_UNSUPPORTED);
541 
542 	if (!efi_cout_modes[mode_number].present)
543 		return EFI_EXIT(EFI_UNSUPPORTED);
544 
545 	efi_con_mode.mode = mode_number;
546 	efi_clear_screen();
547 
548 	return EFI_EXIT(EFI_SUCCESS);
549 }
550 
551 /**
552  * efi_cout_reset() - reset the terminal
553  *
554  * This function implements the Reset service of the simple text output
555  * protocol. See the Unified Extensible Firmware  Interface (UEFI) specification
556  * for details.
557  *
558  * @this:			pointer to the protocol instance
559  * @extended_verification:	if set an extended verification may be executed
560  * Return:			status code
561  */
efi_cout_reset(struct efi_simple_text_output_protocol * this,char extended_verification)562 static efi_status_t EFIAPI efi_cout_reset(
563 			struct efi_simple_text_output_protocol *this,
564 			char extended_verification)
565 {
566 	EFI_ENTRY("%p, %d", this, extended_verification);
567 
568 	/* Set default colors */
569 	efi_con_mode.attribute = 0x07;
570 	printf(ESC "[0;37;40m");
571 	/* Clear screen */
572 	efi_clear_screen();
573 
574 	return EFI_EXIT(EFI_SUCCESS);
575 }
576 
577 /**
578  * efi_cout_set_cursor_position() - reset the terminal
579  *
580  * This function implements the SetCursorPosition service of the simple text
581  * output protocol. See the Unified Extensible Firmware  Interface (UEFI)
582  * specification for details.
583  *
584  * @this:	pointer to the protocol instance
585  * @column:	column to move to
586  * @row:	row to move to
587  * Return:	status code
588  */
efi_cout_set_cursor_position(struct efi_simple_text_output_protocol * this,unsigned long column,unsigned long row)589 static efi_status_t EFIAPI efi_cout_set_cursor_position(
590 			struct efi_simple_text_output_protocol *this,
591 			unsigned long column, unsigned long row)
592 {
593 	efi_status_t ret = EFI_SUCCESS;
594 	struct simple_text_output_mode *con = &efi_con_mode;
595 	struct cout_mode *mode = &efi_cout_modes[con->mode];
596 
597 	EFI_ENTRY("%p, %ld, %ld", this, column, row);
598 
599 	/* Check parameters */
600 	if (!this) {
601 		ret = EFI_INVALID_PARAMETER;
602 		goto out;
603 	}
604 	if (row >= mode->rows || column >= mode->columns) {
605 		ret = EFI_UNSUPPORTED;
606 		goto out;
607 	}
608 
609 	/*
610 	 * Set cursor position by sending CSI H.
611 	 * EFI origin is [0, 0], terminal origin is [1, 1].
612 	 */
613 	printf(ESC "[%d;%dH", (int)row + 1, (int)column + 1);
614 	efi_con_mode.cursor_column = column;
615 	efi_con_mode.cursor_row = row;
616 out:
617 	return EFI_EXIT(ret);
618 }
619 
620 /**
621  * efi_cout_enable_cursor() - enable the cursor
622  *
623  * This function implements the EnableCursor service of the simple text  output
624  * protocol. See the Unified Extensible Firmware  Interface (UEFI) specification
625  * for details.
626  *
627  * @this:	pointer to the protocol instance
628  * @enable:	if true enable, if false disable the cursor
629  * Return:	status code
630  */
efi_cout_enable_cursor(struct efi_simple_text_output_protocol * this,bool enable)631 static efi_status_t EFIAPI efi_cout_enable_cursor(
632 			struct efi_simple_text_output_protocol *this,
633 			bool enable)
634 {
635 	EFI_ENTRY("%p, %d", this, enable);
636 
637 	printf(ESC"[?25%c", enable ? 'h' : 'l');
638 	efi_con_mode.cursor_visible = !!enable;
639 
640 	return EFI_EXIT(EFI_SUCCESS);
641 }
642 
643 struct efi_simple_text_output_protocol efi_con_out = {
644 	.reset = efi_cout_reset,
645 	.output_string = efi_cout_output_string,
646 	.test_string = efi_cout_test_string,
647 	.query_mode = efi_cout_query_mode,
648 	.set_mode = efi_cout_set_mode,
649 	.set_attribute = efi_cout_set_attribute,
650 	.clear_screen = efi_cout_clear_screen,
651 	.set_cursor_position = efi_cout_set_cursor_position,
652 	.enable_cursor = efi_cout_enable_cursor,
653 	.mode = (void*)&efi_con_mode,
654 };
655 
656 /**
657  * struct efi_cin_notify_function - registered console input notify function
658  *
659  * @link:	link to list
660  * @key:	key to notify
661  * @function:	function to call
662  */
663 struct efi_cin_notify_function {
664 	struct list_head link;
665 	struct efi_key_data key;
666 	efi_status_t (EFIAPI *function)
667 		(struct efi_key_data *key_data);
668 };
669 
670 static bool key_available;
671 static struct efi_key_data next_key;
672 static LIST_HEAD(cin_notify_functions);
673 
674 /**
675  * set_shift_mask() - set shift mask
676  *
677  * @mod:	Xterm shift mask
678  * @key_state:  receives the state of the shift, alt, control, and logo keys
679  */
set_shift_mask(int mod,struct efi_key_state * key_state)680 static void set_shift_mask(int mod, struct efi_key_state *key_state)
681 {
682 	key_state->key_shift_state = EFI_SHIFT_STATE_VALID;
683 	if (mod) {
684 		--mod;
685 		if (mod & 1)
686 			key_state->key_shift_state |= EFI_LEFT_SHIFT_PRESSED;
687 		if (mod & 2)
688 			key_state->key_shift_state |= EFI_LEFT_ALT_PRESSED;
689 		if (mod & 4)
690 			key_state->key_shift_state |= EFI_LEFT_CONTROL_PRESSED;
691 		if (!mod || (mod & 8))
692 			key_state->key_shift_state |= EFI_LEFT_LOGO_PRESSED;
693 	}
694 }
695 
696 /**
697  * analyze_modifiers() - analyze modifiers (shift, alt, ctrl) for function keys
698  *
699  * This gets called when we have already parsed CSI.
700  *
701  * @key_state:  receives the state of the shift, alt, control, and logo keys
702  * Return:	the unmodified code
703  */
analyze_modifiers(struct efi_key_state * key_state)704 static int analyze_modifiers(struct efi_key_state *key_state)
705 {
706 	int c, mod = 0, ret = 0;
707 
708 	c = getchar();
709 
710 	if (c != ';') {
711 		ret = c;
712 		if (c == '~')
713 			goto out;
714 		c = getchar();
715 	}
716 	for (;;) {
717 		switch (c) {
718 		case '0'...'9':
719 			mod *= 10;
720 			mod += c - '0';
721 		/* fall through */
722 		case ';':
723 			c = getchar();
724 			break;
725 		default:
726 			goto out;
727 		}
728 	}
729 out:
730 	set_shift_mask(mod, key_state);
731 	if (!ret)
732 		ret = c;
733 	return ret;
734 }
735 
736 /**
737  * efi_cin_read_key() - read a key from the console input
738  *
739  * @key:	- key received
740  * Return:	- status code
741  */
efi_cin_read_key(struct efi_key_data * key)742 static efi_status_t efi_cin_read_key(struct efi_key_data *key)
743 {
744 	struct efi_input_key pressed_key = {
745 		.scan_code = 0,
746 		.unicode_char = 0,
747 	};
748 	s32 ch;
749 
750 	if (console_read_unicode(&ch))
751 		return EFI_NOT_READY;
752 
753 	key->key_state.key_shift_state = EFI_SHIFT_STATE_INVALID;
754 	key->key_state.key_toggle_state = EFI_TOGGLE_STATE_INVALID;
755 
756 	/* We do not support multi-word codes */
757 	if (ch >= 0x10000)
758 		ch = '?';
759 
760 	switch (ch) {
761 	case 0x1b:
762 		/*
763 		 * If a second key is received within 10 ms, assume that we are
764 		 * dealing with an escape sequence. Otherwise consider this the
765 		 * escape key being hit. 10 ms is long enough to work fine at
766 		 * 1200 baud and above.
767 		 */
768 		udelay(10000);
769 		if (!tstc()) {
770 			pressed_key.scan_code = 23;
771 			break;
772 		}
773 		/*
774 		 * Xterm Control Sequences
775 		 * https://www.xfree86.org/4.8.0/ctlseqs.html
776 		 */
777 		ch = getchar();
778 		switch (ch) {
779 		case cESC: /* ESC */
780 			pressed_key.scan_code = 23;
781 			break;
782 		case 'O': /* F1 - F4, End */
783 			ch = getchar();
784 			/* consider modifiers */
785 			if (ch == 'F') { /* End */
786 				pressed_key.scan_code = 6;
787 				break;
788 			} else if (ch < 'P') {
789 				set_shift_mask(ch - '0', &key->key_state);
790 				ch = getchar();
791 			}
792 			pressed_key.scan_code = ch - 'P' + 11;
793 			break;
794 		case '[':
795 			ch = getchar();
796 			switch (ch) {
797 			case 'A'...'D': /* up, down right, left */
798 				pressed_key.scan_code = ch - 'A' + 1;
799 				break;
800 			case 'F': /* End */
801 				pressed_key.scan_code = 6;
802 				break;
803 			case 'H': /* Home */
804 				pressed_key.scan_code = 5;
805 				break;
806 			case '1':
807 				ch = analyze_modifiers(&key->key_state);
808 				switch (ch) {
809 				case '1'...'5': /* F1 - F5 */
810 					pressed_key.scan_code = ch - '1' + 11;
811 					break;
812 				case '6'...'9': /* F5 - F8 */
813 					pressed_key.scan_code = ch - '6' + 15;
814 					break;
815 				case 'A'...'D': /* up, down right, left */
816 					pressed_key.scan_code = ch - 'A' + 1;
817 					break;
818 				case 'F': /* End */
819 					pressed_key.scan_code = 6;
820 					break;
821 				case 'H': /* Home */
822 					pressed_key.scan_code = 5;
823 					break;
824 				case '~': /* Home */
825 					pressed_key.scan_code = 5;
826 					break;
827 				}
828 				break;
829 			case '2':
830 				ch = analyze_modifiers(&key->key_state);
831 				switch (ch) {
832 				case '0'...'1': /* F9 - F10 */
833 					pressed_key.scan_code = ch - '0' + 19;
834 					break;
835 				case '3'...'4': /* F11 - F12 */
836 					pressed_key.scan_code = ch - '3' + 21;
837 					break;
838 				case '~': /* INS */
839 					pressed_key.scan_code = 7;
840 					break;
841 				}
842 				break;
843 			case '3': /* DEL */
844 				pressed_key.scan_code = 8;
845 				analyze_modifiers(&key->key_state);
846 				break;
847 			case '5': /* PG UP */
848 				pressed_key.scan_code = 9;
849 				analyze_modifiers(&key->key_state);
850 				break;
851 			case '6': /* PG DOWN */
852 				pressed_key.scan_code = 10;
853 				analyze_modifiers(&key->key_state);
854 				break;
855 			} /* [ */
856 			break;
857 		default:
858 			/* ALT key */
859 			set_shift_mask(3, &key->key_state);
860 		}
861 		break;
862 	case 0x7f:
863 		/* Backspace */
864 		ch = 0x08;
865 	}
866 	if (pressed_key.scan_code) {
867 		key->key_state.key_shift_state |= EFI_SHIFT_STATE_VALID;
868 	} else {
869 		pressed_key.unicode_char = ch;
870 
871 		/*
872 		 * Assume left control key for control characters typically
873 		 * entered using the control key.
874 		 */
875 		if (ch >= 0x01 && ch <= 0x1f) {
876 			key->key_state.key_shift_state |=
877 					EFI_SHIFT_STATE_VALID;
878 			switch (ch) {
879 			case 0x01 ... 0x07:
880 			case 0x0b ... 0x0c:
881 			case 0x0e ... 0x1f:
882 				key->key_state.key_shift_state |=
883 						EFI_LEFT_CONTROL_PRESSED;
884 			}
885 		}
886 	}
887 	key->key = pressed_key;
888 
889 	return EFI_SUCCESS;
890 }
891 
892 /**
893  * efi_cin_notify() - notify registered functions
894  */
efi_cin_notify(void)895 static void efi_cin_notify(void)
896 {
897 	struct efi_cin_notify_function *item;
898 
899 	list_for_each_entry(item, &cin_notify_functions, link) {
900 		bool match = true;
901 
902 		/* We do not support toggle states */
903 		if (item->key.key.unicode_char || item->key.key.scan_code) {
904 			if (item->key.key.unicode_char !=
905 			    next_key.key.unicode_char ||
906 			    item->key.key.scan_code != next_key.key.scan_code)
907 				match = false;
908 		}
909 		if (item->key.key_state.key_shift_state &&
910 		    item->key.key_state.key_shift_state !=
911 		    next_key.key_state.key_shift_state)
912 			match = false;
913 
914 		if (match)
915 			/* We don't bother about the return code */
916 			EFI_CALL(item->function(&next_key));
917 	}
918 }
919 
920 /**
921  * efi_cin_check() - check if keyboard input is available
922  */
efi_cin_check(void)923 static void efi_cin_check(void)
924 {
925 	efi_status_t ret;
926 
927 	if (key_available) {
928 		efi_signal_event(efi_con_in.wait_for_key);
929 		return;
930 	}
931 
932 	if (tstc()) {
933 		ret = efi_cin_read_key(&next_key);
934 		if (ret == EFI_SUCCESS) {
935 			key_available = true;
936 
937 			/* Notify registered functions */
938 			efi_cin_notify();
939 
940 			/* Queue the wait for key event */
941 			if (key_available)
942 				efi_signal_event(efi_con_in.wait_for_key);
943 		}
944 	}
945 }
946 
947 /**
948  * efi_cin_empty_buffer() - empty input buffer
949  */
efi_cin_empty_buffer(void)950 static void efi_cin_empty_buffer(void)
951 {
952 	while (tstc())
953 		getchar();
954 	key_available = false;
955 }
956 
957 /**
958  * efi_cin_reset_ex() - reset console input
959  *
960  * @this:			- the extended simple text input protocol
961  * @extended_verification:	- extended verification
962  *
963  * This function implements the reset service of the
964  * EFI_SIMPLE_TEXT_INPUT_EX_PROTOCOL.
965  *
966  * See the Unified Extensible Firmware Interface (UEFI) specification for
967  * details.
968  *
969  * Return: old value of the task priority level
970  */
efi_cin_reset_ex(struct efi_simple_text_input_ex_protocol * this,bool extended_verification)971 static efi_status_t EFIAPI efi_cin_reset_ex(
972 		struct efi_simple_text_input_ex_protocol *this,
973 		bool extended_verification)
974 {
975 	efi_status_t ret = EFI_SUCCESS;
976 
977 	EFI_ENTRY("%p, %d", this, extended_verification);
978 
979 	/* Check parameters */
980 	if (!this) {
981 		ret = EFI_INVALID_PARAMETER;
982 		goto out;
983 	}
984 
985 	efi_cin_empty_buffer();
986 out:
987 	return EFI_EXIT(ret);
988 }
989 
990 /**
991  * efi_cin_read_key_stroke_ex() - read key stroke
992  *
993  * @this:	instance of the EFI_SIMPLE_TEXT_INPUT_PROTOCOL
994  * @key_data:	key read from console
995  * Return:	status code
996  *
997  * This function implements the ReadKeyStrokeEx service of the
998  * EFI_SIMPLE_TEXT_INPUT_EX_PROTOCOL.
999  *
1000  * See the Unified Extensible Firmware Interface (UEFI) specification for
1001  * details.
1002  */
efi_cin_read_key_stroke_ex(struct efi_simple_text_input_ex_protocol * this,struct efi_key_data * key_data)1003 static efi_status_t EFIAPI efi_cin_read_key_stroke_ex(
1004 		struct efi_simple_text_input_ex_protocol *this,
1005 		struct efi_key_data *key_data)
1006 {
1007 	efi_status_t ret = EFI_SUCCESS;
1008 
1009 	EFI_ENTRY("%p, %p", this, key_data);
1010 
1011 	/* Check parameters */
1012 	if (!this || !key_data) {
1013 		ret = EFI_INVALID_PARAMETER;
1014 		goto out;
1015 	}
1016 
1017 	/* We don't do interrupts, so check for timers cooperatively */
1018 	efi_timer_check();
1019 
1020 	/* Enable console input after ExitBootServices */
1021 	efi_cin_check();
1022 
1023 	if (!key_available) {
1024 		memset(key_data, 0, sizeof(struct efi_key_data));
1025 		ret = EFI_NOT_READY;
1026 		goto out;
1027 	}
1028 	/*
1029 	 * CTRL+A - CTRL+Z have to be signaled as a - z.
1030 	 * SHIFT+CTRL+A - SHIFT+CTRL+Z have to be signaled as A - Z.
1031 	 * CTRL+\ - CTRL+_ have to be signaled as \ - _.
1032 	 */
1033 	switch (next_key.key.unicode_char) {
1034 	case 0x01 ... 0x07:
1035 	case 0x0b ... 0x0c:
1036 	case 0x0e ... 0x1a:
1037 		if (!(next_key.key_state.key_toggle_state &
1038 		      EFI_CAPS_LOCK_ACTIVE) ^
1039 		    !(next_key.key_state.key_shift_state &
1040 		      (EFI_LEFT_SHIFT_PRESSED | EFI_RIGHT_SHIFT_PRESSED)))
1041 			next_key.key.unicode_char += 0x40;
1042 		else
1043 			next_key.key.unicode_char += 0x60;
1044 		break;
1045 	case 0x1c ... 0x1f:
1046 			next_key.key.unicode_char += 0x40;
1047 	}
1048 	*key_data = next_key;
1049 	key_available = false;
1050 	efi_con_in.wait_for_key->is_signaled = false;
1051 
1052 out:
1053 	return EFI_EXIT(ret);
1054 }
1055 
1056 /**
1057  * efi_cin_set_state() - set toggle key state
1058  *
1059  * @this:		instance of the EFI_SIMPLE_TEXT_INPUT_PROTOCOL
1060  * @key_toggle_state:	pointer to key toggle state
1061  * Return:		status code
1062  *
1063  * This function implements the SetState service of the
1064  * EFI_SIMPLE_TEXT_INPUT_EX_PROTOCOL.
1065  *
1066  * See the Unified Extensible Firmware Interface (UEFI) specification for
1067  * details.
1068  */
efi_cin_set_state(struct efi_simple_text_input_ex_protocol * this,u8 * key_toggle_state)1069 static efi_status_t EFIAPI efi_cin_set_state(
1070 		struct efi_simple_text_input_ex_protocol *this,
1071 		u8 *key_toggle_state)
1072 {
1073 	EFI_ENTRY("%p, %p", this, key_toggle_state);
1074 	/*
1075 	 * U-Boot supports multiple console input sources like serial and
1076 	 * net console for which a key toggle state cannot be set at all.
1077 	 *
1078 	 * According to the UEFI specification it is allowable to not implement
1079 	 * this service.
1080 	 */
1081 	return EFI_EXIT(EFI_UNSUPPORTED);
1082 }
1083 
1084 /**
1085  * efi_cin_register_key_notify() - register key notification function
1086  *
1087  * @this:			instance of the EFI_SIMPLE_TEXT_INPUT_PROTOCOL
1088  * @key_data:			key to be notified
1089  * @key_notify_function:	function to be called if the key is pressed
1090  * @notify_handle:		handle for unregistering the notification
1091  * Return:			status code
1092  *
1093  * This function implements the SetState service of the
1094  * EFI_SIMPLE_TEXT_INPUT_EX_PROTOCOL.
1095  *
1096  * See the Unified Extensible Firmware Interface (UEFI) specification for
1097  * details.
1098  */
efi_cin_register_key_notify(struct efi_simple_text_input_ex_protocol * this,struct efi_key_data * key_data,efi_status_t (EFIAPI * key_notify_function)(struct efi_key_data * key_data),void ** notify_handle)1099 static efi_status_t EFIAPI efi_cin_register_key_notify(
1100 		struct efi_simple_text_input_ex_protocol *this,
1101 		struct efi_key_data *key_data,
1102 		efi_status_t (EFIAPI *key_notify_function)(
1103 			struct efi_key_data *key_data),
1104 		void **notify_handle)
1105 {
1106 	efi_status_t ret = EFI_SUCCESS;
1107 	struct efi_cin_notify_function *notify_function;
1108 
1109 	EFI_ENTRY("%p, %p, %p, %p",
1110 		  this, key_data, key_notify_function, notify_handle);
1111 
1112 	/* Check parameters */
1113 	if (!this || !key_data || !key_notify_function || !notify_handle) {
1114 		ret = EFI_INVALID_PARAMETER;
1115 		goto out;
1116 	}
1117 
1118 	EFI_PRINT("u+%04x, sc %04x, sh %08x, tg %02x\n",
1119 		  key_data->key.unicode_char,
1120 	       key_data->key.scan_code,
1121 	       key_data->key_state.key_shift_state,
1122 	       key_data->key_state.key_toggle_state);
1123 
1124 	notify_function = calloc(1, sizeof(struct efi_cin_notify_function));
1125 	if (!notify_function) {
1126 		ret = EFI_OUT_OF_RESOURCES;
1127 		goto out;
1128 	}
1129 	notify_function->key = *key_data;
1130 	notify_function->function = key_notify_function;
1131 	list_add_tail(&notify_function->link, &cin_notify_functions);
1132 	*notify_handle = notify_function;
1133 out:
1134 	return EFI_EXIT(ret);
1135 }
1136 
1137 /**
1138  * efi_cin_unregister_key_notify() - unregister key notification function
1139  *
1140  * @this:			instance of the EFI_SIMPLE_TEXT_INPUT_PROTOCOL
1141  * @notification_handle:	handle received when registering
1142  * Return:			status code
1143  *
1144  * This function implements the SetState service of the
1145  * EFI_SIMPLE_TEXT_INPUT_EX_PROTOCOL.
1146  *
1147  * See the Unified Extensible Firmware Interface (UEFI) specification for
1148  * details.
1149  */
efi_cin_unregister_key_notify(struct efi_simple_text_input_ex_protocol * this,void * notification_handle)1150 static efi_status_t EFIAPI efi_cin_unregister_key_notify(
1151 		struct efi_simple_text_input_ex_protocol *this,
1152 		void *notification_handle)
1153 {
1154 	efi_status_t ret = EFI_INVALID_PARAMETER;
1155 	struct efi_cin_notify_function *item, *notify_function =
1156 			notification_handle;
1157 
1158 	EFI_ENTRY("%p, %p", this, notification_handle);
1159 
1160 	/* Check parameters */
1161 	if (!this || !notification_handle)
1162 		goto out;
1163 
1164 	list_for_each_entry(item, &cin_notify_functions, link) {
1165 		if (item == notify_function) {
1166 			ret = EFI_SUCCESS;
1167 			break;
1168 		}
1169 	}
1170 	if (ret != EFI_SUCCESS)
1171 		goto out;
1172 
1173 	/* Remove the notify function */
1174 	list_del(&notify_function->link);
1175 	free(notify_function);
1176 out:
1177 	return EFI_EXIT(ret);
1178 }
1179 
1180 
1181 /**
1182  * efi_cin_reset() - drain the input buffer
1183  *
1184  * @this:			instance of the EFI_SIMPLE_TEXT_INPUT_PROTOCOL
1185  * @extended_verification:	allow for exhaustive verification
1186  * Return:			status code
1187  *
1188  * This function implements the Reset service of the
1189  * EFI_SIMPLE_TEXT_INPUT_PROTOCOL.
1190  *
1191  * See the Unified Extensible Firmware Interface (UEFI) specification for
1192  * details.
1193  */
efi_cin_reset(struct efi_simple_text_input_protocol * this,bool extended_verification)1194 static efi_status_t EFIAPI efi_cin_reset
1195 			(struct efi_simple_text_input_protocol *this,
1196 			 bool extended_verification)
1197 {
1198 	efi_status_t ret = EFI_SUCCESS;
1199 
1200 	EFI_ENTRY("%p, %d", this, extended_verification);
1201 
1202 	/* Check parameters */
1203 	if (!this) {
1204 		ret = EFI_INVALID_PARAMETER;
1205 		goto out;
1206 	}
1207 
1208 	efi_cin_empty_buffer();
1209 out:
1210 	return EFI_EXIT(ret);
1211 }
1212 
1213 /**
1214  * efi_cin_read_key_stroke() - read key stroke
1215  *
1216  * @this:	instance of the EFI_SIMPLE_TEXT_INPUT_PROTOCOL
1217  * @key:	key read from console
1218  * Return:	status code
1219  *
1220  * This function implements the ReadKeyStroke service of the
1221  * EFI_SIMPLE_TEXT_INPUT_PROTOCOL.
1222  *
1223  * See the Unified Extensible Firmware Interface (UEFI) specification for
1224  * details.
1225  */
efi_cin_read_key_stroke(struct efi_simple_text_input_protocol * this,struct efi_input_key * key)1226 static efi_status_t EFIAPI efi_cin_read_key_stroke
1227 			(struct efi_simple_text_input_protocol *this,
1228 			 struct efi_input_key *key)
1229 {
1230 	efi_status_t ret = EFI_SUCCESS;
1231 
1232 	EFI_ENTRY("%p, %p", this, key);
1233 
1234 	/* Check parameters */
1235 	if (!this || !key) {
1236 		ret = EFI_INVALID_PARAMETER;
1237 		goto out;
1238 	}
1239 
1240 	/* We don't do interrupts, so check for timers cooperatively */
1241 	efi_timer_check();
1242 
1243 	/* Enable console input after ExitBootServices */
1244 	efi_cin_check();
1245 
1246 	if (!key_available) {
1247 		ret = EFI_NOT_READY;
1248 		goto out;
1249 	}
1250 	*key = next_key.key;
1251 	key_available = false;
1252 	efi_con_in.wait_for_key->is_signaled = false;
1253 out:
1254 	return EFI_EXIT(ret);
1255 }
1256 
1257 static struct efi_simple_text_input_ex_protocol efi_con_in_ex = {
1258 	.reset = efi_cin_reset_ex,
1259 	.read_key_stroke_ex = efi_cin_read_key_stroke_ex,
1260 	.wait_for_key_ex = NULL,
1261 	.set_state = efi_cin_set_state,
1262 	.register_key_notify = efi_cin_register_key_notify,
1263 	.unregister_key_notify = efi_cin_unregister_key_notify,
1264 };
1265 
1266 struct efi_simple_text_input_protocol efi_con_in = {
1267 	.reset = efi_cin_reset,
1268 	.read_key_stroke = efi_cin_read_key_stroke,
1269 	.wait_for_key = NULL,
1270 };
1271 
1272 static struct efi_event *console_timer_event;
1273 
1274 /*
1275  * efi_console_timer_notify() - notify the console timer event
1276  *
1277  * @event:	console timer event
1278  * @context:	not used
1279  */
efi_console_timer_notify(struct efi_event * event,void * context)1280 static void EFIAPI efi_console_timer_notify(struct efi_event *event,
1281 					    void *context)
1282 {
1283 	EFI_ENTRY("%p, %p", event, context);
1284 	efi_cin_check();
1285 	EFI_EXIT(EFI_SUCCESS);
1286 }
1287 
1288 /**
1289  * efi_key_notify() - notify the wait for key event
1290  *
1291  * @event:	wait for key event
1292  * @context:	not used
1293  */
efi_key_notify(struct efi_event * event,void * context)1294 static void EFIAPI efi_key_notify(struct efi_event *event, void *context)
1295 {
1296 	EFI_ENTRY("%p, %p", event, context);
1297 	efi_cin_check();
1298 	EFI_EXIT(EFI_SUCCESS);
1299 }
1300 
1301 /**
1302  * efi_console_register() - install the console protocols
1303  *
1304  * This function is called from do_bootefi_exec().
1305  *
1306  * Return:	status code
1307  */
efi_console_register(void)1308 efi_status_t efi_console_register(void)
1309 {
1310 	efi_status_t r;
1311 	struct efi_device_path *dp;
1312 
1313 	/* Install protocols on root node */
1314 	r = efi_install_multiple_protocol_interfaces(&efi_root,
1315 						     &efi_guid_text_output_protocol,
1316 						     &efi_con_out,
1317 						     &efi_guid_text_input_protocol,
1318 						     &efi_con_in,
1319 						     &efi_guid_text_input_ex_protocol,
1320 						     &efi_con_in_ex,
1321 						     NULL);
1322 
1323 	/* Create console node and install device path protocols */
1324 	if (CONFIG_IS_ENABLED(DM_SERIAL)) {
1325 		dp = efi_dp_from_uart();
1326 		if (!dp)
1327 			goto out_of_memory;
1328 
1329 		/* Hook UART up to the device list */
1330 		efi_add_handle(&uart_obj);
1331 
1332 		/* Install device path */
1333 		r = efi_add_protocol(&uart_obj, &efi_guid_device_path, dp);
1334 		if (r != EFI_SUCCESS)
1335 			goto out_of_memory;
1336 	}
1337 
1338 	/* Create console events */
1339 	r = efi_create_event(EVT_NOTIFY_WAIT, TPL_CALLBACK, efi_key_notify,
1340 			     NULL, NULL, &efi_con_in.wait_for_key);
1341 	if (r != EFI_SUCCESS) {
1342 		printf("ERROR: Failed to register WaitForKey event\n");
1343 		return r;
1344 	}
1345 	efi_con_in_ex.wait_for_key_ex = efi_con_in.wait_for_key;
1346 	r = efi_create_event(EVT_TIMER | EVT_NOTIFY_SIGNAL, TPL_CALLBACK,
1347 			     efi_console_timer_notify, NULL, NULL,
1348 			     &console_timer_event);
1349 	if (r != EFI_SUCCESS) {
1350 		printf("ERROR: Failed to register console event\n");
1351 		return r;
1352 	}
1353 	/* 5000 ns cycle is sufficient for 2 MBaud */
1354 	r = efi_set_timer(console_timer_event, EFI_TIMER_PERIODIC, 50);
1355 	if (r != EFI_SUCCESS)
1356 		printf("ERROR: Failed to set console timer\n");
1357 	return r;
1358 out_of_memory:
1359 	printf("ERROR: Out of memory\n");
1360 	return r;
1361 }
1362 
1363 /**
1364  * efi_console_get_u16_string() - get user input string
1365  *
1366  * @cin:		protocol interface to EFI_SIMPLE_TEXT_INPUT_PROTOCOL
1367  * @buf:		buffer to store user input string in UTF16
1368  * @count:		number of u16 string including NULL terminator that buf has
1369  * @filter_func:	callback to filter user input
1370  * @row:		row number to locate user input form
1371  * @col:		column number to locate user input form
1372  * Return:		status code
1373  */
efi_console_get_u16_string(struct efi_simple_text_input_protocol * cin,u16 * buf,efi_uintn_t count,efi_console_filter_func filter_func,int row,int col)1374 efi_status_t efi_console_get_u16_string(struct efi_simple_text_input_protocol *cin,
1375 					u16 *buf, efi_uintn_t count,
1376 					efi_console_filter_func filter_func,
1377 					int row, int col)
1378 {
1379 	efi_status_t ret;
1380 	efi_uintn_t len = 0;
1381 	struct efi_input_key key;
1382 
1383 	printf(ANSI_CURSOR_POSITION
1384 	       ANSI_CLEAR_LINE_TO_END
1385 	       ANSI_CURSOR_SHOW, row, col);
1386 
1387 	efi_cin_empty_buffer();
1388 
1389 	for (;;) {
1390 		do {
1391 			ret = EFI_CALL(cin->read_key_stroke(cin, &key));
1392 			mdelay(10);
1393 		} while (ret == EFI_NOT_READY);
1394 
1395 		if (key.unicode_char == u'\b') {
1396 			if (len > 0)
1397 				buf[--len] = u'\0';
1398 
1399 			printf(ANSI_CURSOR_POSITION
1400 			       "%ls"
1401 			       ANSI_CLEAR_LINE_TO_END, row, col, buf);
1402 			continue;
1403 		} else if (key.unicode_char == u'\r') {
1404 			buf[len] = u'\0';
1405 			return EFI_SUCCESS;
1406 		} else if (key.unicode_char == 0x3 || key.scan_code == 23) {
1407 			return EFI_ABORTED;
1408 		} else if (key.unicode_char < 0x20) {
1409 			/* ignore control codes other than Ctrl+C, '\r' and '\b' */
1410 			continue;
1411 		} else if (key.scan_code != 0) {
1412 			/* only accept single ESC press for cancel */
1413 			continue;
1414 		}
1415 
1416 		if (filter_func) {
1417 			if (filter_func(&key) != EFI_SUCCESS)
1418 				continue;
1419 		}
1420 
1421 		if (len >= (count - 1))
1422 			continue;
1423 
1424 		buf[len] = key.unicode_char;
1425 		len++;
1426 		printf(ANSI_CURSOR_POSITION "%ls", row, col, buf);
1427 	}
1428 }
1429