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 static const struct os_area_db_id os_area_db_id_video_mode = {
198 	.owner = OS_AREA_DB_OWNER_LINUX,
199 	.key = OS_AREA_DB_KEY_VIDEO_MODE
200 };
201 
202 #define SECONDS_FROM_1970_TO_2000 946684800LL
203 
204 /**
205  * struct saved_params - Static working copies of data from the PS3 'os area'.
206  *
207  * The order of preference we use for the rtc_diff source:
208  *  1) The database value.
209  *  2) The game os value.
210  *  3) The number of seconds from 1970 to 2000.
211  */
212 
213 struct saved_params {
214 	unsigned int valid;
215 	s64 rtc_diff;
216 	unsigned int av_multi_out;
217 } static saved_params;
218 
219 static struct property property_rtc_diff = {
220 	.name = "linux,rtc_diff",
221 	.length = sizeof(saved_params.rtc_diff),
222 	.value = &saved_params.rtc_diff,
223 };
224 
225 static struct property property_av_multi_out = {
226 	.name = "linux,av_multi_out",
227 	.length = sizeof(saved_params.av_multi_out),
228 	.value = &saved_params.av_multi_out,
229 };
230 
231 
232 static DEFINE_MUTEX(os_area_flash_mutex);
233 
234 static const struct ps3_os_area_flash_ops *os_area_flash_ops;
235 
236 void ps3_os_area_flash_register(const struct ps3_os_area_flash_ops *ops)
237 {
238 	mutex_lock(&os_area_flash_mutex);
239 	os_area_flash_ops = ops;
240 	mutex_unlock(&os_area_flash_mutex);
241 }
242 EXPORT_SYMBOL_GPL(ps3_os_area_flash_register);
243 
244 static ssize_t os_area_flash_read(void *buf, size_t count, loff_t pos)
245 {
246 	ssize_t res = -ENODEV;
247 
248 	mutex_lock(&os_area_flash_mutex);
249 	if (os_area_flash_ops)
250 		res = os_area_flash_ops->read(buf, count, pos);
251 	mutex_unlock(&os_area_flash_mutex);
252 
253 	return res;
254 }
255 
256 static ssize_t os_area_flash_write(const void *buf, size_t count, loff_t pos)
257 {
258 	ssize_t res = -ENODEV;
259 
260 	mutex_lock(&os_area_flash_mutex);
261 	if (os_area_flash_ops)
262 		res = os_area_flash_ops->write(buf, count, pos);
263 	mutex_unlock(&os_area_flash_mutex);
264 
265 	return res;
266 }
267 
268 
269 /**
270  * os_area_set_property - Add or overwrite a saved_params value to the device tree.
271  *
272  * Overwrites an existing property.
273  */
274 
275 static void os_area_set_property(struct device_node *node,
276 	struct property *prop)
277 {
278 	int result;
279 	struct property *tmp = of_find_property(node, prop->name, NULL);
280 
281 	if (tmp) {
282 		pr_debug("%s:%d found %s\n", __func__, __LINE__, prop->name);
283 		of_remove_property(node, tmp);
284 	}
285 
286 	result = of_add_property(node, prop);
287 
288 	if (result)
289 		pr_debug("%s:%d of_set_property failed\n", __func__,
290 			__LINE__);
291 }
292 
293 /**
294  * os_area_get_property - Get a saved_params value from the device tree.
295  *
296  */
297 
298 static void __init os_area_get_property(struct device_node *node,
299 	struct property *prop)
300 {
301 	const struct property *tmp = of_find_property(node, prop->name, NULL);
302 
303 	if (tmp) {
304 		BUG_ON(prop->length != tmp->length);
305 		memcpy(prop->value, tmp->value, prop->length);
306 	} else
307 		pr_debug("%s:%d not found %s\n", __func__, __LINE__,
308 			prop->name);
309 }
310 
311 static void dump_field(char *s, const u8 *field, int size_of_field)
312 {
313 #if defined(DEBUG)
314 	int i;
315 
316 	for (i = 0; i < size_of_field; i++)
317 		s[i] = isprint(field[i]) ? field[i] : '.';
318 	s[i] = 0;
319 #endif
320 }
321 
322 #define dump_header(_a) _dump_header(_a, __func__, __LINE__)
323 static void _dump_header(const struct os_area_header *h, const char *func,
324 	int line)
325 {
326 	char str[sizeof(h->magic_num) + 1];
327 
328 	dump_field(str, h->magic_num, sizeof(h->magic_num));
329 	pr_debug("%s:%d: h.magic_num:       '%s'\n", func, line,
330 		str);
331 	pr_debug("%s:%d: h.hdr_version:     %u\n", func, line,
332 		h->hdr_version);
333 	pr_debug("%s:%d: h.db_area_offset:  %u\n", func, line,
334 		h->db_area_offset);
335 	pr_debug("%s:%d: h.ldr_area_offset: %u\n", func, line,
336 		h->ldr_area_offset);
337 	pr_debug("%s:%d: h.ldr_format:      %u\n", func, line,
338 		h->ldr_format);
339 	pr_debug("%s:%d: h.ldr_size:        %xh\n", func, line,
340 		h->ldr_size);
341 }
342 
343 #define dump_params(_a) _dump_params(_a, __func__, __LINE__)
344 static void _dump_params(const struct os_area_params *p, const char *func,
345 	int line)
346 {
347 	pr_debug("%s:%d: p.boot_flag:       %u\n", func, line, p->boot_flag);
348 	pr_debug("%s:%d: p.num_params:      %u\n", func, line, p->num_params);
349 	pr_debug("%s:%d: p.rtc_diff         %lld\n", func, line, p->rtc_diff);
350 	pr_debug("%s:%d: p.av_multi_out     %u\n", func, line, p->av_multi_out);
351 	pr_debug("%s:%d: p.ctrl_button:     %u\n", func, line, p->ctrl_button);
352 	pr_debug("%s:%d: p.static_ip_addr:  %u.%u.%u.%u\n", func, line,
353 		p->static_ip_addr[0], p->static_ip_addr[1],
354 		p->static_ip_addr[2], p->static_ip_addr[3]);
355 	pr_debug("%s:%d: p.network_mask:    %u.%u.%u.%u\n", func, line,
356 		p->network_mask[0], p->network_mask[1],
357 		p->network_mask[2], p->network_mask[3]);
358 	pr_debug("%s:%d: p.default_gateway: %u.%u.%u.%u\n", func, line,
359 		p->default_gateway[0], p->default_gateway[1],
360 		p->default_gateway[2], p->default_gateway[3]);
361 	pr_debug("%s:%d: p.dns_primary:     %u.%u.%u.%u\n", func, line,
362 		p->dns_primary[0], p->dns_primary[1],
363 		p->dns_primary[2], p->dns_primary[3]);
364 	pr_debug("%s:%d: p.dns_secondary:   %u.%u.%u.%u\n", func, line,
365 		p->dns_secondary[0], p->dns_secondary[1],
366 		p->dns_secondary[2], p->dns_secondary[3]);
367 }
368 
369 static int verify_header(const struct os_area_header *header)
370 {
371 	if (memcmp(header->magic_num, OS_AREA_HEADER_MAGIC_NUM,
372 		sizeof(header->magic_num))) {
373 		pr_debug("%s:%d magic_num failed\n", __func__, __LINE__);
374 		return -1;
375 	}
376 
377 	if (header->hdr_version < 1) {
378 		pr_debug("%s:%d hdr_version failed\n", __func__, __LINE__);
379 		return -1;
380 	}
381 
382 	if (header->db_area_offset > header->ldr_area_offset) {
383 		pr_debug("%s:%d offsets failed\n", __func__, __LINE__);
384 		return -1;
385 	}
386 
387 	return 0;
388 }
389 
390 static int db_verify(const struct os_area_db *db)
391 {
392 	if (memcmp(db->magic_num, OS_AREA_DB_MAGIC_NUM,
393 		sizeof(db->magic_num))) {
394 		pr_debug("%s:%d magic_num failed\n", __func__, __LINE__);
395 		return -EINVAL;
396 	}
397 
398 	if (db->version != 1) {
399 		pr_debug("%s:%d version failed\n", __func__, __LINE__);
400 		return -EINVAL;
401 	}
402 
403 	return 0;
404 }
405 
406 struct db_index {
407        uint8_t owner:5;
408        uint8_t key:3;
409 };
410 
411 struct db_iterator {
412 	const struct os_area_db *db;
413 	struct os_area_db_id match_id;
414 	struct db_index *idx;
415 	struct db_index *last_idx;
416 	union {
417 		uint64_t *value_64;
418 		uint32_t *value_32;
419 		uint16_t *value_16;
420 	};
421 };
422 
423 static unsigned int db_align_up(unsigned int val, unsigned int size)
424 {
425 	return (val + (size - 1)) & (~(size - 1));
426 }
427 
428 /**
429  * db_for_each_64 - Iterator for 64 bit entries.
430  *
431  * A NULL value for id can be used to match all entries.
432  * OS_AREA_DB_OWNER_ANY and OS_AREA_DB_KEY_ANY can be used to match all.
433  */
434 
435 static int db_for_each_64(const struct os_area_db *db,
436 	const struct os_area_db_id *match_id, struct db_iterator *i)
437 {
438 next:
439 	if (!i->db) {
440 		i->db = db;
441 		i->match_id = match_id ? *match_id : os_area_db_id_any;
442 		i->idx = (void *)db + db->index_64;
443 		i->last_idx = i->idx + db->count_64;
444 		i->value_64 = (void *)db + db->index_64
445 			+ db_align_up(db->count_64, 8);
446 	} else {
447 		i->idx++;
448 		i->value_64++;
449 	}
450 
451 	if (i->idx >= i->last_idx) {
452 		pr_debug("%s:%d: reached end\n", __func__, __LINE__);
453 		return 0;
454 	}
455 
456 	if (i->match_id.owner != OS_AREA_DB_OWNER_ANY
457 		&& i->match_id.owner != (int)i->idx->owner)
458 		goto next;
459 	if (i->match_id.key != OS_AREA_DB_KEY_ANY
460 		&& i->match_id.key != (int)i->idx->key)
461 		goto next;
462 
463 	return 1;
464 }
465 
466 static int db_delete_64(struct os_area_db *db, const struct os_area_db_id *id)
467 {
468 	struct db_iterator i;
469 
470 	for (i.db = NULL; db_for_each_64(db, id, &i); ) {
471 
472 		pr_debug("%s:%d: got (%d:%d) %llxh\n", __func__, __LINE__,
473 			i.idx->owner, i.idx->key,
474 			(unsigned long long)*i.value_64);
475 
476 		i.idx->owner = 0;
477 		i.idx->key = 0;
478 		*i.value_64 = 0;
479 	}
480 	return 0;
481 }
482 
483 static int db_set_64(struct os_area_db *db, const struct os_area_db_id *id,
484 	uint64_t value)
485 {
486 	struct db_iterator i;
487 
488 	pr_debug("%s:%d: (%d:%d) <= %llxh\n", __func__, __LINE__,
489 		id->owner, id->key, (unsigned long long)value);
490 
491 	if (!id->owner || id->owner == OS_AREA_DB_OWNER_ANY
492 		|| id->key == OS_AREA_DB_KEY_ANY) {
493 		pr_debug("%s:%d: bad id: (%d:%d)\n", __func__,
494 			__LINE__, id->owner, id->key);
495 		return -1;
496 	}
497 
498 	db_delete_64(db, id);
499 
500 	i.db = NULL;
501 	if (db_for_each_64(db, &os_area_db_id_empty, &i)) {
502 
503 		pr_debug("%s:%d: got (%d:%d) %llxh\n", __func__, __LINE__,
504 			i.idx->owner, i.idx->key,
505 			(unsigned long long)*i.value_64);
506 
507 		i.idx->owner = id->owner;
508 		i.idx->key = id->key;
509 		*i.value_64 = value;
510 
511 		pr_debug("%s:%d: set (%d:%d) <= %llxh\n", __func__, __LINE__,
512 			i.idx->owner, i.idx->key,
513 			(unsigned long long)*i.value_64);
514 		return 0;
515 	}
516 	pr_debug("%s:%d: database full.\n",
517 		__func__, __LINE__);
518 	return -1;
519 }
520 
521 static int db_get_64(const struct os_area_db *db,
522 	const struct os_area_db_id *id, uint64_t *value)
523 {
524 	struct db_iterator i;
525 
526 	i.db = NULL;
527 	if (db_for_each_64(db, id, &i)) {
528 		*value = *i.value_64;
529 		pr_debug("%s:%d: found %lld\n", __func__, __LINE__,
530 				(long long int)*i.value_64);
531 		return 0;
532 	}
533 	pr_debug("%s:%d: not found\n", __func__, __LINE__);
534 	return -1;
535 }
536 
537 static int db_get_rtc_diff(const struct os_area_db *db, int64_t *rtc_diff)
538 {
539 	return db_get_64(db, &os_area_db_id_rtc_diff, (uint64_t*)rtc_diff);
540 }
541 
542 #define dump_db(a) _dump_db(a, __func__, __LINE__)
543 static void _dump_db(const struct os_area_db *db, const char *func,
544 	int line)
545 {
546 	char str[sizeof(db->magic_num) + 1];
547 
548 	dump_field(str, db->magic_num, sizeof(db->magic_num));
549 	pr_debug("%s:%d: db.magic_num:      '%s'\n", func, line,
550 		str);
551 	pr_debug("%s:%d: db.version:         %u\n", func, line,
552 		db->version);
553 	pr_debug("%s:%d: db.index_64:        %u\n", func, line,
554 		db->index_64);
555 	pr_debug("%s:%d: db.count_64:        %u\n", func, line,
556 		db->count_64);
557 	pr_debug("%s:%d: db.index_32:        %u\n", func, line,
558 		db->index_32);
559 	pr_debug("%s:%d: db.count_32:        %u\n", func, line,
560 		db->count_32);
561 	pr_debug("%s:%d: db.index_16:        %u\n", func, line,
562 		db->index_16);
563 	pr_debug("%s:%d: db.count_16:        %u\n", func, line,
564 		db->count_16);
565 }
566 
567 static void os_area_db_init(struct os_area_db *db)
568 {
569 	enum {
570 		HEADER_SIZE = offsetof(struct os_area_db, _db_data),
571 		INDEX_64_COUNT = 64,
572 		VALUES_64_COUNT = 57,
573 		INDEX_32_COUNT = 64,
574 		VALUES_32_COUNT = 57,
575 		INDEX_16_COUNT = 64,
576 		VALUES_16_COUNT = 57,
577 	};
578 
579 	memset(db, 0, sizeof(struct os_area_db));
580 
581 	memcpy(db->magic_num, OS_AREA_DB_MAGIC_NUM, sizeof(db->magic_num));
582 	db->version = 1;
583 	db->index_64 = HEADER_SIZE;
584 	db->count_64 = VALUES_64_COUNT;
585 	db->index_32 = HEADER_SIZE
586 			+ INDEX_64_COUNT * sizeof(struct db_index)
587 			+ VALUES_64_COUNT * sizeof(u64);
588 	db->count_32 = VALUES_32_COUNT;
589 	db->index_16 = HEADER_SIZE
590 			+ INDEX_64_COUNT * sizeof(struct db_index)
591 			+ VALUES_64_COUNT * sizeof(u64)
592 			+ INDEX_32_COUNT * sizeof(struct db_index)
593 			+ VALUES_32_COUNT * sizeof(u32);
594 	db->count_16 = VALUES_16_COUNT;
595 
596 	/* Rules to check db layout. */
597 
598 	BUILD_BUG_ON(sizeof(struct db_index) != 1);
599 	BUILD_BUG_ON(sizeof(struct os_area_db) != 2 * OS_AREA_SEGMENT_SIZE);
600 	BUILD_BUG_ON(INDEX_64_COUNT & 0x7);
601 	BUILD_BUG_ON(VALUES_64_COUNT > INDEX_64_COUNT);
602 	BUILD_BUG_ON(INDEX_32_COUNT & 0x7);
603 	BUILD_BUG_ON(VALUES_32_COUNT > INDEX_32_COUNT);
604 	BUILD_BUG_ON(INDEX_16_COUNT & 0x7);
605 	BUILD_BUG_ON(VALUES_16_COUNT > INDEX_16_COUNT);
606 	BUILD_BUG_ON(HEADER_SIZE
607 			+ INDEX_64_COUNT * sizeof(struct db_index)
608 			+ VALUES_64_COUNT * sizeof(u64)
609 			+ INDEX_32_COUNT * sizeof(struct db_index)
610 			+ VALUES_32_COUNT * sizeof(u32)
611 			+ INDEX_16_COUNT * sizeof(struct db_index)
612 			+ VALUES_16_COUNT * sizeof(u16)
613 			> sizeof(struct os_area_db));
614 }
615 
616 /**
617  * update_flash_db - Helper for os_area_queue_work_handler.
618  *
619  */
620 
621 static int update_flash_db(void)
622 {
623 	const unsigned int buf_len = 8 * OS_AREA_SEGMENT_SIZE;
624 	struct os_area_header *header;
625 	ssize_t count;
626 	int error;
627 	loff_t pos;
628 	struct os_area_db* db;
629 
630 	/* Read in header and db from flash. */
631 
632 	header = kmalloc(buf_len, GFP_KERNEL);
633 	if (!header) {
634 		pr_debug("%s: kmalloc failed\n", __func__);
635 		return -ENOMEM;
636 	}
637 
638 	count = os_area_flash_read(header, buf_len, 0);
639 	if (count < 0) {
640 		pr_debug("%s: os_area_flash_read failed %zd\n", __func__,
641 			 count);
642 		error = count;
643 		goto fail;
644 	}
645 
646 	pos = header->db_area_offset * OS_AREA_SEGMENT_SIZE;
647 	if (count < OS_AREA_SEGMENT_SIZE || verify_header(header) ||
648 	    count < pos) {
649 		pr_debug("%s: verify_header failed\n", __func__);
650 		dump_header(header);
651 		error = -EINVAL;
652 		goto fail;
653 	}
654 
655 	/* Now got a good db offset and some maybe good db data. */
656 
657 	db = (void *)header + pos;
658 
659 	error = db_verify(db);
660 	if (error) {
661 		pr_notice("%s: Verify of flash database failed, formatting.\n",
662 			  __func__);
663 		dump_db(db);
664 		os_area_db_init(db);
665 	}
666 
667 	/* Now got good db data. */
668 
669 	db_set_64(db, &os_area_db_id_rtc_diff, saved_params.rtc_diff);
670 
671 	count = os_area_flash_write(db, sizeof(struct os_area_db), pos);
672 	if (count < sizeof(struct os_area_db)) {
673 		pr_debug("%s: os_area_flash_write failed %zd\n", __func__,
674 			 count);
675 		error = count < 0 ? count : -EIO;
676 	}
677 
678 fail:
679 	kfree(header);
680 	return error;
681 }
682 
683 /**
684  * os_area_queue_work_handler - Asynchronous write handler.
685  *
686  * An asynchronous write for flash memory and the device tree.  Do not
687  * call directly, use os_area_queue_work().
688  */
689 
690 static void os_area_queue_work_handler(struct work_struct *work)
691 {
692 	struct device_node *node;
693 	int error;
694 
695 	pr_debug(" -> %s:%d\n", __func__, __LINE__);
696 
697 	node = of_find_node_by_path("/");
698 	if (node) {
699 		os_area_set_property(node, &property_rtc_diff);
700 		of_node_put(node);
701 	} else
702 		pr_debug("%s:%d of_find_node_by_path failed\n",
703 			__func__, __LINE__);
704 
705 	error = update_flash_db();
706 	if (error)
707 		pr_warning("%s: Could not update FLASH ROM\n", __func__);
708 
709 	pr_debug(" <- %s:%d\n", __func__, __LINE__);
710 }
711 
712 static void os_area_queue_work(void)
713 {
714 	static DECLARE_WORK(q, os_area_queue_work_handler);
715 
716 	wmb();
717 	schedule_work(&q);
718 }
719 
720 /**
721  * ps3_os_area_save_params - Copy data from os area mirror to @saved_params.
722  *
723  * For the convenience of the guest the HV makes a copy of the os area in
724  * flash to a high address in the boot memory region and then puts that RAM
725  * address and the byte count into the repository for retrieval by the guest.
726  * We copy the data we want into a static variable and allow the memory setup
727  * by the HV to be claimed by the memblock manager.
728  *
729  * The os area mirror will not be available to a second stage kernel, and
730  * the header verify will fail.  In this case, the saved_params values will
731  * be set from flash memory or the passed in device tree in ps3_os_area_init().
732  */
733 
734 void __init ps3_os_area_save_params(void)
735 {
736 	int result;
737 	u64 lpar_addr;
738 	unsigned int size;
739 	struct os_area_header *header;
740 	struct os_area_params *params;
741 	struct os_area_db *db;
742 
743 	pr_debug(" -> %s:%d\n", __func__, __LINE__);
744 
745 	result = ps3_repository_read_boot_dat_info(&lpar_addr, &size);
746 
747 	if (result) {
748 		pr_debug("%s:%d ps3_repository_read_boot_dat_info failed\n",
749 			__func__, __LINE__);
750 		return;
751 	}
752 
753 	header = (struct os_area_header *)__va(lpar_addr);
754 	params = (struct os_area_params *)__va(lpar_addr
755 		+ OS_AREA_SEGMENT_SIZE);
756 
757 	result = verify_header(header);
758 
759 	if (result) {
760 		/* Second stage kernels exit here. */
761 		pr_debug("%s:%d verify_header failed\n", __func__, __LINE__);
762 		dump_header(header);
763 		return;
764 	}
765 
766 	db = (struct os_area_db *)__va(lpar_addr
767 		+ header->db_area_offset * OS_AREA_SEGMENT_SIZE);
768 
769 	dump_header(header);
770 	dump_params(params);
771 	dump_db(db);
772 
773 	result = db_verify(db) || db_get_rtc_diff(db, &saved_params.rtc_diff);
774 	if (result)
775 		saved_params.rtc_diff = params->rtc_diff ? params->rtc_diff
776 			: SECONDS_FROM_1970_TO_2000;
777 	saved_params.av_multi_out = params->av_multi_out;
778 	saved_params.valid = 1;
779 
780 	memset(header, 0, sizeof(*header));
781 
782 	pr_debug(" <- %s:%d\n", __func__, __LINE__);
783 }
784 
785 /**
786  * ps3_os_area_init - Setup os area device tree properties as needed.
787  */
788 
789 void __init ps3_os_area_init(void)
790 {
791 	struct device_node *node;
792 
793 	pr_debug(" -> %s:%d\n", __func__, __LINE__);
794 
795 	node = of_find_node_by_path("/");
796 
797 	if (!saved_params.valid && node) {
798 		/* Second stage kernels should have a dt entry. */
799 		os_area_get_property(node, &property_rtc_diff);
800 		os_area_get_property(node, &property_av_multi_out);
801 	}
802 
803 	if(!saved_params.rtc_diff)
804 		saved_params.rtc_diff = SECONDS_FROM_1970_TO_2000;
805 
806 	if (node) {
807 		os_area_set_property(node, &property_rtc_diff);
808 		os_area_set_property(node, &property_av_multi_out);
809 		of_node_put(node);
810 	} else
811 		pr_debug("%s:%d of_find_node_by_path failed\n",
812 			__func__, __LINE__);
813 
814 	pr_debug(" <- %s:%d\n", __func__, __LINE__);
815 }
816 
817 /**
818  * ps3_os_area_get_rtc_diff - Returns the rtc diff value.
819  */
820 
821 u64 ps3_os_area_get_rtc_diff(void)
822 {
823 	return saved_params.rtc_diff;
824 }
825 EXPORT_SYMBOL_GPL(ps3_os_area_get_rtc_diff);
826 
827 /**
828  * ps3_os_area_set_rtc_diff - Set the rtc diff value.
829  *
830  * An asynchronous write is needed to support writing updates from
831  * the timer interrupt context.
832  */
833 
834 void ps3_os_area_set_rtc_diff(u64 rtc_diff)
835 {
836 	if (saved_params.rtc_diff != rtc_diff) {
837 		saved_params.rtc_diff = rtc_diff;
838 		os_area_queue_work();
839 	}
840 }
841 EXPORT_SYMBOL_GPL(ps3_os_area_set_rtc_diff);
842 
843 /**
844  * ps3_os_area_get_av_multi_out - Returns the default video mode.
845  */
846 
847 enum ps3_param_av_multi_out ps3_os_area_get_av_multi_out(void)
848 {
849     return saved_params.av_multi_out;
850 }
851 EXPORT_SYMBOL_GPL(ps3_os_area_get_av_multi_out);
852