1 /*
2  *  PS3 flash memory os area.
3  *
4  *  Copyright (C) 2006 Sony Computer Entertainment Inc.
5  *  Copyright 2006 Sony Corp.
6  *
7  *  This program is free software; you can redistribute it and/or modify
8  *  it under the terms of the GNU General Public License as published by
9  *  the Free Software Foundation; version 2 of the License.
10  *
11  *  This program is distributed in the hope that it will be useful,
12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  *  GNU General Public License for more details.
15  *
16  *  You should have received a copy of the GNU General Public License
17  *  along with this program; if not, write to the Free Software
18  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
19  */
20 
21 #include <linux/kernel.h>
22 #include <linux/io.h>
23 #include <linux/workqueue.h>
24 #include <linux/fs.h>
25 #include <linux/syscalls.h>
26 #include <linux/ctype.h>
27 #include <linux/lmb.h>
28 #include <linux/of.h>
29 #include <linux/slab.h>
30 
31 #include <asm/prom.h>
32 
33 #include "platform.h"
34 
35 enum {
36 	OS_AREA_SEGMENT_SIZE = 0X200,
37 };
38 
39 enum os_area_ldr_format {
40 	HEADER_LDR_FORMAT_RAW = 0,
41 	HEADER_LDR_FORMAT_GZIP = 1,
42 };
43 
44 #define OS_AREA_HEADER_MAGIC_NUM "cell_ext_os_area"
45 
46 /**
47  * struct os_area_header - os area header segment.
48  * @magic_num: Always 'cell_ext_os_area'.
49  * @hdr_version: Header format version number.
50  * @db_area_offset: Starting segment number of other os database area.
51  * @ldr_area_offset: Starting segment number of bootloader image area.
52  * @ldr_format: HEADER_LDR_FORMAT flag.
53  * @ldr_size: Size of bootloader image in bytes.
54  *
55  * Note that the docs refer to area offsets.  These are offsets in units of
56  * segments from the start of the os area (top of the header).  These are
57  * better thought of as segment numbers.  The os area of the os area is
58  * reserved for the os image.
59  */
60 
61 struct os_area_header {
62 	u8 magic_num[16];
63 	u32 hdr_version;
64 	u32 db_area_offset;
65 	u32 ldr_area_offset;
66 	u32 _reserved_1;
67 	u32 ldr_format;
68 	u32 ldr_size;
69 	u32 _reserved_2[6];
70 };
71 
72 enum os_area_boot_flag {
73 	PARAM_BOOT_FLAG_GAME_OS = 0,
74 	PARAM_BOOT_FLAG_OTHER_OS = 1,
75 };
76 
77 enum os_area_ctrl_button {
78 	PARAM_CTRL_BUTTON_O_IS_YES = 0,
79 	PARAM_CTRL_BUTTON_X_IS_YES = 1,
80 };
81 
82 /**
83  * struct os_area_params - os area params segment.
84  * @boot_flag: User preference of operating system, PARAM_BOOT_FLAG flag.
85  * @num_params: Number of params in this (params) segment.
86  * @rtc_diff: Difference in seconds between 1970 and the ps3 rtc value.
87  * @av_multi_out: User preference of AV output, PARAM_AV_MULTI_OUT flag.
88  * @ctrl_button: User preference of controller button config, PARAM_CTRL_BUTTON
89  *	flag.
90  * @static_ip_addr: User preference of static IP address.
91  * @network_mask: User preference of static network mask.
92  * @default_gateway: User preference of static default gateway.
93  * @dns_primary: User preference of static primary dns server.
94  * @dns_secondary: User preference of static secondary dns server.
95  *
96  * The ps3 rtc maintains a read-only value that approximates seconds since
97  * 2000-01-01 00:00:00 UTC.
98  *
99  * User preference of zero for static_ip_addr means use dhcp.
100  */
101 
102 struct os_area_params {
103 	u32 boot_flag;
104 	u32 _reserved_1[3];
105 	u32 num_params;
106 	u32 _reserved_2[3];
107 	/* param 0 */
108 	s64 rtc_diff;
109 	u8 av_multi_out;
110 	u8 ctrl_button;
111 	u8 _reserved_3[6];
112 	/* param 1 */
113 	u8 static_ip_addr[4];
114 	u8 network_mask[4];
115 	u8 default_gateway[4];
116 	u8 _reserved_4[4];
117 	/* param 2 */
118 	u8 dns_primary[4];
119 	u8 dns_secondary[4];
120 	u8 _reserved_5[8];
121 };
122 
123 #define OS_AREA_DB_MAGIC_NUM "-db-"
124 
125 /**
126  * struct os_area_db - Shared flash memory database.
127  * @magic_num: Always '-db-'.
128  * @version: os_area_db format version number.
129  * @index_64: byte offset of the database id index for 64 bit variables.
130  * @count_64: number of usable 64 bit index entries
131  * @index_32: byte offset of the database id index for 32 bit variables.
132  * @count_32: number of usable 32 bit index entries
133  * @index_16: byte offset of the database id index for 16 bit variables.
134  * @count_16: number of usable 16 bit index entries
135  *
136  * Flash rom storage for exclusive use by guests running in the other os lpar.
137  * The current system configuration allocates 1K (two segments) for other os
138  * use.
139  */
140 
141 struct os_area_db {
142 	u8 magic_num[4];
143 	u16 version;
144 	u16 _reserved_1;
145 	u16 index_64;
146 	u16 count_64;
147 	u16 index_32;
148 	u16 count_32;
149 	u16 index_16;
150 	u16 count_16;
151 	u32 _reserved_2;
152 	u8 _db_data[1000];
153 };
154 
155 /**
156  * enum os_area_db_owner - Data owners.
157  */
158 
159 enum os_area_db_owner {
160 	OS_AREA_DB_OWNER_ANY = -1,
161 	OS_AREA_DB_OWNER_NONE = 0,
162 	OS_AREA_DB_OWNER_PROTOTYPE = 1,
163 	OS_AREA_DB_OWNER_LINUX = 2,
164 	OS_AREA_DB_OWNER_PETITBOOT = 3,
165 	OS_AREA_DB_OWNER_MAX = 32,
166 };
167 
168 enum os_area_db_key {
169 	OS_AREA_DB_KEY_ANY = -1,
170 	OS_AREA_DB_KEY_NONE = 0,
171 	OS_AREA_DB_KEY_RTC_DIFF = 1,
172 	OS_AREA_DB_KEY_VIDEO_MODE = 2,
173 	OS_AREA_DB_KEY_MAX = 8,
174 };
175 
176 struct os_area_db_id {
177 	int owner;
178 	int key;
179 };
180 
181 static const struct os_area_db_id os_area_db_id_empty = {
182 	.owner = OS_AREA_DB_OWNER_NONE,
183 	.key = OS_AREA_DB_KEY_NONE
184 };
185 
186 static const struct os_area_db_id os_area_db_id_any = {
187 	.owner = OS_AREA_DB_OWNER_ANY,
188 	.key = OS_AREA_DB_KEY_ANY
189 };
190 
191 static const struct os_area_db_id os_area_db_id_rtc_diff = {
192 	.owner = OS_AREA_DB_OWNER_LINUX,
193 	.key = OS_AREA_DB_KEY_RTC_DIFF
194 };
195 
196 static const struct os_area_db_id os_area_db_id_video_mode = {
197 	.owner = OS_AREA_DB_OWNER_LINUX,
198 	.key = OS_AREA_DB_KEY_VIDEO_MODE
199 };
200 
201 #define SECONDS_FROM_1970_TO_2000 946684800LL
202 
203 /**
204  * struct saved_params - Static working copies of data from the PS3 'os area'.
205  *
206  * The order of preference we use for the rtc_diff source:
207  *  1) The database value.
208  *  2) The game os value.
209  *  3) The number of seconds from 1970 to 2000.
210  */
211 
212 struct saved_params {
213 	unsigned int valid;
214 	s64 rtc_diff;
215 	unsigned int av_multi_out;
216 } static saved_params;
217 
218 static struct property property_rtc_diff = {
219 	.name = "linux,rtc_diff",
220 	.length = sizeof(saved_params.rtc_diff),
221 	.value = &saved_params.rtc_diff,
222 };
223 
224 static struct property property_av_multi_out = {
225 	.name = "linux,av_multi_out",
226 	.length = sizeof(saved_params.av_multi_out),
227 	.value = &saved_params.av_multi_out,
228 };
229 
230 
231 static DEFINE_MUTEX(os_area_flash_mutex);
232 
233 static const struct ps3_os_area_flash_ops *os_area_flash_ops;
234 
235 void ps3_os_area_flash_register(const struct ps3_os_area_flash_ops *ops)
236 {
237 	mutex_lock(&os_area_flash_mutex);
238 	os_area_flash_ops = ops;
239 	mutex_unlock(&os_area_flash_mutex);
240 }
241 EXPORT_SYMBOL_GPL(ps3_os_area_flash_register);
242 
243 static ssize_t os_area_flash_read(void *buf, size_t count, loff_t pos)
244 {
245 	ssize_t res = -ENODEV;
246 
247 	mutex_lock(&os_area_flash_mutex);
248 	if (os_area_flash_ops)
249 		res = os_area_flash_ops->read(buf, count, pos);
250 	mutex_unlock(&os_area_flash_mutex);
251 
252 	return res;
253 }
254 
255 static ssize_t os_area_flash_write(const void *buf, size_t count, loff_t pos)
256 {
257 	ssize_t res = -ENODEV;
258 
259 	mutex_lock(&os_area_flash_mutex);
260 	if (os_area_flash_ops)
261 		res = os_area_flash_ops->write(buf, count, pos);
262 	mutex_unlock(&os_area_flash_mutex);
263 
264 	return res;
265 }
266 
267 
268 /**
269  * os_area_set_property - Add or overwrite a saved_params value to the device tree.
270  *
271  * Overwrites an existing property.
272  */
273 
274 static void os_area_set_property(struct device_node *node,
275 	struct property *prop)
276 {
277 	int result;
278 	struct property *tmp = of_find_property(node, prop->name, NULL);
279 
280 	if (tmp) {
281 		pr_debug("%s:%d found %s\n", __func__, __LINE__, prop->name);
282 		prom_remove_property(node, tmp);
283 	}
284 
285 	result = prom_add_property(node, prop);
286 
287 	if (result)
288 		pr_debug("%s:%d prom_set_property failed\n", __func__,
289 			__LINE__);
290 }
291 
292 /**
293  * os_area_get_property - Get a saved_params value from the device tree.
294  *
295  */
296 
297 static void __init os_area_get_property(struct device_node *node,
298 	struct property *prop)
299 {
300 	const struct property *tmp = of_find_property(node, prop->name, NULL);
301 
302 	if (tmp) {
303 		BUG_ON(prop->length != tmp->length);
304 		memcpy(prop->value, tmp->value, prop->length);
305 	} else
306 		pr_debug("%s:%d not found %s\n", __func__, __LINE__,
307 			prop->name);
308 }
309 
310 static void dump_field(char *s, const u8 *field, int size_of_field)
311 {
312 #if defined(DEBUG)
313 	int i;
314 
315 	for (i = 0; i < size_of_field; i++)
316 		s[i] = isprint(field[i]) ? field[i] : '.';
317 	s[i] = 0;
318 #endif
319 }
320 
321 #define dump_header(_a) _dump_header(_a, __func__, __LINE__)
322 static void _dump_header(const struct os_area_header *h, const char *func,
323 	int line)
324 {
325 	char str[sizeof(h->magic_num) + 1];
326 
327 	dump_field(str, h->magic_num, sizeof(h->magic_num));
328 	pr_debug("%s:%d: h.magic_num:       '%s'\n", func, line,
329 		str);
330 	pr_debug("%s:%d: h.hdr_version:     %u\n", func, line,
331 		h->hdr_version);
332 	pr_debug("%s:%d: h.db_area_offset:  %u\n", func, line,
333 		h->db_area_offset);
334 	pr_debug("%s:%d: h.ldr_area_offset: %u\n", func, line,
335 		h->ldr_area_offset);
336 	pr_debug("%s:%d: h.ldr_format:      %u\n", func, line,
337 		h->ldr_format);
338 	pr_debug("%s:%d: h.ldr_size:        %xh\n", func, line,
339 		h->ldr_size);
340 }
341 
342 #define dump_params(_a) _dump_params(_a, __func__, __LINE__)
343 static void _dump_params(const struct os_area_params *p, const char *func,
344 	int line)
345 {
346 	pr_debug("%s:%d: p.boot_flag:       %u\n", func, line, p->boot_flag);
347 	pr_debug("%s:%d: p.num_params:      %u\n", func, line, p->num_params);
348 	pr_debug("%s:%d: p.rtc_diff         %lld\n", func, line, p->rtc_diff);
349 	pr_debug("%s:%d: p.av_multi_out     %u\n", func, line, p->av_multi_out);
350 	pr_debug("%s:%d: p.ctrl_button:     %u\n", func, line, p->ctrl_button);
351 	pr_debug("%s:%d: p.static_ip_addr:  %u.%u.%u.%u\n", func, line,
352 		p->static_ip_addr[0], p->static_ip_addr[1],
353 		p->static_ip_addr[2], p->static_ip_addr[3]);
354 	pr_debug("%s:%d: p.network_mask:    %u.%u.%u.%u\n", func, line,
355 		p->network_mask[0], p->network_mask[1],
356 		p->network_mask[2], p->network_mask[3]);
357 	pr_debug("%s:%d: p.default_gateway: %u.%u.%u.%u\n", func, line,
358 		p->default_gateway[0], p->default_gateway[1],
359 		p->default_gateway[2], p->default_gateway[3]);
360 	pr_debug("%s:%d: p.dns_primary:     %u.%u.%u.%u\n", func, line,
361 		p->dns_primary[0], p->dns_primary[1],
362 		p->dns_primary[2], p->dns_primary[3]);
363 	pr_debug("%s:%d: p.dns_secondary:   %u.%u.%u.%u\n", func, line,
364 		p->dns_secondary[0], p->dns_secondary[1],
365 		p->dns_secondary[2], p->dns_secondary[3]);
366 }
367 
368 static int verify_header(const struct os_area_header *header)
369 {
370 	if (memcmp(header->magic_num, OS_AREA_HEADER_MAGIC_NUM,
371 		sizeof(header->magic_num))) {
372 		pr_debug("%s:%d magic_num failed\n", __func__, __LINE__);
373 		return -1;
374 	}
375 
376 	if (header->hdr_version < 1) {
377 		pr_debug("%s:%d hdr_version failed\n", __func__, __LINE__);
378 		return -1;
379 	}
380 
381 	if (header->db_area_offset > header->ldr_area_offset) {
382 		pr_debug("%s:%d offsets failed\n", __func__, __LINE__);
383 		return -1;
384 	}
385 
386 	return 0;
387 }
388 
389 static int db_verify(const struct os_area_db *db)
390 {
391 	if (memcmp(db->magic_num, OS_AREA_DB_MAGIC_NUM,
392 		sizeof(db->magic_num))) {
393 		pr_debug("%s:%d magic_num failed\n", __func__, __LINE__);
394 		return -EINVAL;
395 	}
396 
397 	if (db->version != 1) {
398 		pr_debug("%s:%d version failed\n", __func__, __LINE__);
399 		return -EINVAL;
400 	}
401 
402 	return 0;
403 }
404 
405 struct db_index {
406        uint8_t owner:5;
407        uint8_t key:3;
408 };
409 
410 struct db_iterator {
411 	const struct os_area_db *db;
412 	struct os_area_db_id match_id;
413 	struct db_index *idx;
414 	struct db_index *last_idx;
415 	union {
416 		uint64_t *value_64;
417 		uint32_t *value_32;
418 		uint16_t *value_16;
419 	};
420 };
421 
422 static unsigned int db_align_up(unsigned int val, unsigned int size)
423 {
424 	return (val + (size - 1)) & (~(size - 1));
425 }
426 
427 /**
428  * db_for_each_64 - Iterator for 64 bit entries.
429  *
430  * A NULL value for id can be used to match all entries.
431  * OS_AREA_DB_OWNER_ANY and OS_AREA_DB_KEY_ANY can be used to match all.
432  */
433 
434 static int db_for_each_64(const struct os_area_db *db,
435 	const struct os_area_db_id *match_id, struct db_iterator *i)
436 {
437 next:
438 	if (!i->db) {
439 		i->db = db;
440 		i->match_id = match_id ? *match_id : os_area_db_id_any;
441 		i->idx = (void *)db + db->index_64;
442 		i->last_idx = i->idx + db->count_64;
443 		i->value_64 = (void *)db + db->index_64
444 			+ db_align_up(db->count_64, 8);
445 	} else {
446 		i->idx++;
447 		i->value_64++;
448 	}
449 
450 	if (i->idx >= i->last_idx) {
451 		pr_debug("%s:%d: reached end\n", __func__, __LINE__);
452 		return 0;
453 	}
454 
455 	if (i->match_id.owner != OS_AREA_DB_OWNER_ANY
456 		&& i->match_id.owner != (int)i->idx->owner)
457 		goto next;
458 	if (i->match_id.key != OS_AREA_DB_KEY_ANY
459 		&& i->match_id.key != (int)i->idx->key)
460 		goto next;
461 
462 	return 1;
463 }
464 
465 static int db_delete_64(struct os_area_db *db, const struct os_area_db_id *id)
466 {
467 	struct db_iterator i;
468 
469 	for (i.db = NULL; db_for_each_64(db, id, &i); ) {
470 
471 		pr_debug("%s:%d: got (%d:%d) %llxh\n", __func__, __LINE__,
472 			i.idx->owner, i.idx->key,
473 			(unsigned long long)*i.value_64);
474 
475 		i.idx->owner = 0;
476 		i.idx->key = 0;
477 		*i.value_64 = 0;
478 	}
479 	return 0;
480 }
481 
482 static int db_set_64(struct os_area_db *db, const struct os_area_db_id *id,
483 	uint64_t value)
484 {
485 	struct db_iterator i;
486 
487 	pr_debug("%s:%d: (%d:%d) <= %llxh\n", __func__, __LINE__,
488 		id->owner, id->key, (unsigned long long)value);
489 
490 	if (!id->owner || id->owner == OS_AREA_DB_OWNER_ANY
491 		|| id->key == OS_AREA_DB_KEY_ANY) {
492 		pr_debug("%s:%d: bad id: (%d:%d)\n", __func__,
493 			__LINE__, id->owner, id->key);
494 		return -1;
495 	}
496 
497 	db_delete_64(db, id);
498 
499 	i.db = NULL;
500 	if (db_for_each_64(db, &os_area_db_id_empty, &i)) {
501 
502 		pr_debug("%s:%d: got (%d:%d) %llxh\n", __func__, __LINE__,
503 			i.idx->owner, i.idx->key,
504 			(unsigned long long)*i.value_64);
505 
506 		i.idx->owner = id->owner;
507 		i.idx->key = id->key;
508 		*i.value_64 = value;
509 
510 		pr_debug("%s:%d: set (%d:%d) <= %llxh\n", __func__, __LINE__,
511 			i.idx->owner, i.idx->key,
512 			(unsigned long long)*i.value_64);
513 		return 0;
514 	}
515 	pr_debug("%s:%d: database full.\n",
516 		__func__, __LINE__);
517 	return -1;
518 }
519 
520 static int db_get_64(const struct os_area_db *db,
521 	const struct os_area_db_id *id, uint64_t *value)
522 {
523 	struct db_iterator i;
524 
525 	i.db = NULL;
526 	if (db_for_each_64(db, id, &i)) {
527 		*value = *i.value_64;
528 		pr_debug("%s:%d: found %lld\n", __func__, __LINE__,
529 				(long long int)*i.value_64);
530 		return 0;
531 	}
532 	pr_debug("%s:%d: not found\n", __func__, __LINE__);
533 	return -1;
534 }
535 
536 static int db_get_rtc_diff(const struct os_area_db *db, int64_t *rtc_diff)
537 {
538 	return db_get_64(db, &os_area_db_id_rtc_diff, (uint64_t*)rtc_diff);
539 }
540 
541 #define dump_db(a) _dump_db(a, __func__, __LINE__)
542 static void _dump_db(const struct os_area_db *db, const char *func,
543 	int line)
544 {
545 	char str[sizeof(db->magic_num) + 1];
546 
547 	dump_field(str, db->magic_num, sizeof(db->magic_num));
548 	pr_debug("%s:%d: db.magic_num:      '%s'\n", func, line,
549 		str);
550 	pr_debug("%s:%d: db.version:         %u\n", func, line,
551 		db->version);
552 	pr_debug("%s:%d: db.index_64:        %u\n", func, line,
553 		db->index_64);
554 	pr_debug("%s:%d: db.count_64:        %u\n", func, line,
555 		db->count_64);
556 	pr_debug("%s:%d: db.index_32:        %u\n", func, line,
557 		db->index_32);
558 	pr_debug("%s:%d: db.count_32:        %u\n", func, line,
559 		db->count_32);
560 	pr_debug("%s:%d: db.index_16:        %u\n", func, line,
561 		db->index_16);
562 	pr_debug("%s:%d: db.count_16:        %u\n", func, line,
563 		db->count_16);
564 }
565 
566 static void os_area_db_init(struct os_area_db *db)
567 {
568 	enum {
569 		HEADER_SIZE = offsetof(struct os_area_db, _db_data),
570 		INDEX_64_COUNT = 64,
571 		VALUES_64_COUNT = 57,
572 		INDEX_32_COUNT = 64,
573 		VALUES_32_COUNT = 57,
574 		INDEX_16_COUNT = 64,
575 		VALUES_16_COUNT = 57,
576 	};
577 
578 	memset(db, 0, sizeof(struct os_area_db));
579 
580 	memcpy(db->magic_num, OS_AREA_DB_MAGIC_NUM, sizeof(db->magic_num));
581 	db->version = 1;
582 	db->index_64 = HEADER_SIZE;
583 	db->count_64 = VALUES_64_COUNT;
584 	db->index_32 = HEADER_SIZE
585 			+ INDEX_64_COUNT * sizeof(struct db_index)
586 			+ VALUES_64_COUNT * sizeof(u64);
587 	db->count_32 = VALUES_32_COUNT;
588 	db->index_16 = HEADER_SIZE
589 			+ INDEX_64_COUNT * sizeof(struct db_index)
590 			+ VALUES_64_COUNT * sizeof(u64)
591 			+ INDEX_32_COUNT * sizeof(struct db_index)
592 			+ VALUES_32_COUNT * sizeof(u32);
593 	db->count_16 = VALUES_16_COUNT;
594 
595 	/* Rules to check db layout. */
596 
597 	BUILD_BUG_ON(sizeof(struct db_index) != 1);
598 	BUILD_BUG_ON(sizeof(struct os_area_db) != 2 * OS_AREA_SEGMENT_SIZE);
599 	BUILD_BUG_ON(INDEX_64_COUNT & 0x7);
600 	BUILD_BUG_ON(VALUES_64_COUNT > INDEX_64_COUNT);
601 	BUILD_BUG_ON(INDEX_32_COUNT & 0x7);
602 	BUILD_BUG_ON(VALUES_32_COUNT > INDEX_32_COUNT);
603 	BUILD_BUG_ON(INDEX_16_COUNT & 0x7);
604 	BUILD_BUG_ON(VALUES_16_COUNT > INDEX_16_COUNT);
605 	BUILD_BUG_ON(HEADER_SIZE
606 			+ INDEX_64_COUNT * sizeof(struct db_index)
607 			+ VALUES_64_COUNT * sizeof(u64)
608 			+ INDEX_32_COUNT * sizeof(struct db_index)
609 			+ VALUES_32_COUNT * sizeof(u32)
610 			+ INDEX_16_COUNT * sizeof(struct db_index)
611 			+ VALUES_16_COUNT * sizeof(u16)
612 			> sizeof(struct os_area_db));
613 }
614 
615 /**
616  * update_flash_db - Helper for os_area_queue_work_handler.
617  *
618  */
619 
620 static int update_flash_db(void)
621 {
622 	const unsigned int buf_len = 8 * OS_AREA_SEGMENT_SIZE;
623 	struct os_area_header *header;
624 	ssize_t count;
625 	int error;
626 	loff_t pos;
627 	struct os_area_db* db;
628 
629 	/* Read in header and db from flash. */
630 
631 	header = kmalloc(buf_len, GFP_KERNEL);
632 	if (!header) {
633 		pr_debug("%s: kmalloc failed\n", __func__);
634 		return -ENOMEM;
635 	}
636 
637 	count = os_area_flash_read(header, buf_len, 0);
638 	if (count < 0) {
639 		pr_debug("%s: os_area_flash_read failed %zd\n", __func__,
640 			 count);
641 		error = count;
642 		goto fail;
643 	}
644 
645 	pos = header->db_area_offset * OS_AREA_SEGMENT_SIZE;
646 	if (count < OS_AREA_SEGMENT_SIZE || verify_header(header) ||
647 	    count < pos) {
648 		pr_debug("%s: verify_header failed\n", __func__);
649 		dump_header(header);
650 		error = -EINVAL;
651 		goto fail;
652 	}
653 
654 	/* Now got a good db offset and some maybe good db data. */
655 
656 	db = (void *)header + pos;
657 
658 	error = db_verify(db);
659 	if (error) {
660 		pr_notice("%s: Verify of flash database failed, formatting.\n",
661 			  __func__);
662 		dump_db(db);
663 		os_area_db_init(db);
664 	}
665 
666 	/* Now got good db data. */
667 
668 	db_set_64(db, &os_area_db_id_rtc_diff, saved_params.rtc_diff);
669 
670 	count = os_area_flash_write(db, sizeof(struct os_area_db), pos);
671 	if (count < sizeof(struct os_area_db)) {
672 		pr_debug("%s: os_area_flash_write failed %zd\n", __func__,
673 			 count);
674 		error = count < 0 ? count : -EIO;
675 	}
676 
677 fail:
678 	kfree(header);
679 	return error;
680 }
681 
682 /**
683  * os_area_queue_work_handler - Asynchronous write handler.
684  *
685  * An asynchronous write for flash memory and the device tree.  Do not
686  * call directly, use os_area_queue_work().
687  */
688 
689 static void os_area_queue_work_handler(struct work_struct *work)
690 {
691 	struct device_node *node;
692 	int error;
693 
694 	pr_debug(" -> %s:%d\n", __func__, __LINE__);
695 
696 	node = of_find_node_by_path("/");
697 	if (node) {
698 		os_area_set_property(node, &property_rtc_diff);
699 		of_node_put(node);
700 	} else
701 		pr_debug("%s:%d of_find_node_by_path failed\n",
702 			__func__, __LINE__);
703 
704 	error = update_flash_db();
705 	if (error)
706 		pr_warning("%s: Could not update FLASH ROM\n", __func__);
707 
708 	pr_debug(" <- %s:%d\n", __func__, __LINE__);
709 }
710 
711 static void os_area_queue_work(void)
712 {
713 	static DECLARE_WORK(q, os_area_queue_work_handler);
714 
715 	wmb();
716 	schedule_work(&q);
717 }
718 
719 /**
720  * ps3_os_area_save_params - Copy data from os area mirror to @saved_params.
721  *
722  * For the convenience of the guest the HV makes a copy of the os area in
723  * flash to a high address in the boot memory region and then puts that RAM
724  * address and the byte count into the repository for retrieval by the guest.
725  * We copy the data we want into a static variable and allow the memory setup
726  * by the HV to be claimed by the lmb manager.
727  *
728  * The os area mirror will not be available to a second stage kernel, and
729  * the header verify will fail.  In this case, the saved_params values will
730  * be set from flash memory or the passed in device tree in ps3_os_area_init().
731  */
732 
733 void __init ps3_os_area_save_params(void)
734 {
735 	int result;
736 	u64 lpar_addr;
737 	unsigned int size;
738 	struct os_area_header *header;
739 	struct os_area_params *params;
740 	struct os_area_db *db;
741 
742 	pr_debug(" -> %s:%d\n", __func__, __LINE__);
743 
744 	result = ps3_repository_read_boot_dat_info(&lpar_addr, &size);
745 
746 	if (result) {
747 		pr_debug("%s:%d ps3_repository_read_boot_dat_info failed\n",
748 			__func__, __LINE__);
749 		return;
750 	}
751 
752 	header = (struct os_area_header *)__va(lpar_addr);
753 	params = (struct os_area_params *)__va(lpar_addr
754 		+ OS_AREA_SEGMENT_SIZE);
755 
756 	result = verify_header(header);
757 
758 	if (result) {
759 		/* Second stage kernels exit here. */
760 		pr_debug("%s:%d verify_header failed\n", __func__, __LINE__);
761 		dump_header(header);
762 		return;
763 	}
764 
765 	db = (struct os_area_db *)__va(lpar_addr
766 		+ header->db_area_offset * OS_AREA_SEGMENT_SIZE);
767 
768 	dump_header(header);
769 	dump_params(params);
770 	dump_db(db);
771 
772 	result = db_verify(db) || db_get_rtc_diff(db, &saved_params.rtc_diff);
773 	if (result)
774 		saved_params.rtc_diff = params->rtc_diff ? params->rtc_diff
775 			: SECONDS_FROM_1970_TO_2000;
776 	saved_params.av_multi_out = params->av_multi_out;
777 	saved_params.valid = 1;
778 
779 	memset(header, 0, sizeof(*header));
780 
781 	pr_debug(" <- %s:%d\n", __func__, __LINE__);
782 }
783 
784 /**
785  * ps3_os_area_init - Setup os area device tree properties as needed.
786  */
787 
788 void __init ps3_os_area_init(void)
789 {
790 	struct device_node *node;
791 
792 	pr_debug(" -> %s:%d\n", __func__, __LINE__);
793 
794 	node = of_find_node_by_path("/");
795 
796 	if (!saved_params.valid && node) {
797 		/* Second stage kernels should have a dt entry. */
798 		os_area_get_property(node, &property_rtc_diff);
799 		os_area_get_property(node, &property_av_multi_out);
800 	}
801 
802 	if(!saved_params.rtc_diff)
803 		saved_params.rtc_diff = SECONDS_FROM_1970_TO_2000;
804 
805 	if (node) {
806 		os_area_set_property(node, &property_rtc_diff);
807 		os_area_set_property(node, &property_av_multi_out);
808 		of_node_put(node);
809 	} else
810 		pr_debug("%s:%d of_find_node_by_path failed\n",
811 			__func__, __LINE__);
812 
813 	pr_debug(" <- %s:%d\n", __func__, __LINE__);
814 }
815 
816 /**
817  * ps3_os_area_get_rtc_diff - Returns the rtc diff value.
818  */
819 
820 u64 ps3_os_area_get_rtc_diff(void)
821 {
822 	return saved_params.rtc_diff;
823 }
824 EXPORT_SYMBOL_GPL(ps3_os_area_get_rtc_diff);
825 
826 /**
827  * ps3_os_area_set_rtc_diff - Set the rtc diff value.
828  *
829  * An asynchronous write is needed to support writing updates from
830  * the timer interrupt context.
831  */
832 
833 void ps3_os_area_set_rtc_diff(u64 rtc_diff)
834 {
835 	if (saved_params.rtc_diff != rtc_diff) {
836 		saved_params.rtc_diff = rtc_diff;
837 		os_area_queue_work();
838 	}
839 }
840 EXPORT_SYMBOL_GPL(ps3_os_area_set_rtc_diff);
841 
842 /**
843  * ps3_os_area_get_av_multi_out - Returns the default video mode.
844  */
845 
846 enum ps3_param_av_multi_out ps3_os_area_get_av_multi_out(void)
847 {
848     return saved_params.av_multi_out;
849 }
850 EXPORT_SYMBOL_GPL(ps3_os_area_get_av_multi_out);
851