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