1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  PS3 flash memory os area.
4  *
5  *  Copyright (C) 2006 Sony Computer Entertainment Inc.
6  *  Copyright 2006 Sony Corp.
7  */
8 
9 #include <linux/kernel.h>
10 #include <linux/io.h>
11 #include <linux/workqueue.h>
12 #include <linux/fs.h>
13 #include <linux/syscalls.h>
14 #include <linux/export.h>
15 #include <linux/ctype.h>
16 #include <linux/memblock.h>
17 #include <linux/of.h>
18 #include <linux/slab.h>
19 
20 #include "platform.h"
21 
22 enum {
23 	OS_AREA_SEGMENT_SIZE = 0X200,
24 };
25 
26 enum os_area_ldr_format {
27 	HEADER_LDR_FORMAT_RAW = 0,
28 	HEADER_LDR_FORMAT_GZIP = 1,
29 };
30 
31 #define OS_AREA_HEADER_MAGIC_NUM "cell_ext_os_area"
32 
33 /**
34  * struct os_area_header - os area header segment.
35  * @magic_num: Always 'cell_ext_os_area'.
36  * @hdr_version: Header format version number.
37  * @db_area_offset: Starting segment number of other os database area.
38  * @ldr_area_offset: Starting segment number of bootloader image area.
39  * @ldr_format: HEADER_LDR_FORMAT flag.
40  * @ldr_size: Size of bootloader image in bytes.
41  *
42  * Note that the docs refer to area offsets.  These are offsets in units of
43  * segments from the start of the os area (top of the header).  These are
44  * better thought of as segment numbers.  The os area of the os area is
45  * reserved for the os image.
46  */
47 
48 struct os_area_header {
49 	u8 magic_num[16];
50 	u32 hdr_version;
51 	u32 db_area_offset;
52 	u32 ldr_area_offset;
53 	u32 _reserved_1;
54 	u32 ldr_format;
55 	u32 ldr_size;
56 	u32 _reserved_2[6];
57 };
58 
59 enum os_area_boot_flag {
60 	PARAM_BOOT_FLAG_GAME_OS = 0,
61 	PARAM_BOOT_FLAG_OTHER_OS = 1,
62 };
63 
64 enum os_area_ctrl_button {
65 	PARAM_CTRL_BUTTON_O_IS_YES = 0,
66 	PARAM_CTRL_BUTTON_X_IS_YES = 1,
67 };
68 
69 /**
70  * struct os_area_params - os area params segment.
71  * @boot_flag: User preference of operating system, PARAM_BOOT_FLAG flag.
72  * @num_params: Number of params in this (params) segment.
73  * @rtc_diff: Difference in seconds between 1970 and the ps3 rtc value.
74  * @av_multi_out: User preference of AV output, PARAM_AV_MULTI_OUT flag.
75  * @ctrl_button: User preference of controller button config, PARAM_CTRL_BUTTON
76  *	flag.
77  * @static_ip_addr: User preference of static IP address.
78  * @network_mask: User preference of static network mask.
79  * @default_gateway: User preference of static default gateway.
80  * @dns_primary: User preference of static primary dns server.
81  * @dns_secondary: User preference of static secondary dns server.
82  *
83  * The ps3 rtc maintains a read-only value that approximates seconds since
84  * 2000-01-01 00:00:00 UTC.
85  *
86  * User preference of zero for static_ip_addr means use dhcp.
87  */
88 
89 struct os_area_params {
90 	u32 boot_flag;
91 	u32 _reserved_1[3];
92 	u32 num_params;
93 	u32 _reserved_2[3];
94 	/* param 0 */
95 	s64 rtc_diff;
96 	u8 av_multi_out;
97 	u8 ctrl_button;
98 	u8 _reserved_3[6];
99 	/* param 1 */
100 	u8 static_ip_addr[4];
101 	u8 network_mask[4];
102 	u8 default_gateway[4];
103 	u8 _reserved_4[4];
104 	/* param 2 */
105 	u8 dns_primary[4];
106 	u8 dns_secondary[4];
107 	u8 _reserved_5[8];
108 };
109 
110 #define OS_AREA_DB_MAGIC_NUM "-db-"
111 
112 /**
113  * struct os_area_db - Shared flash memory database.
114  * @magic_num: Always '-db-'.
115  * @version: os_area_db format version number.
116  * @index_64: byte offset of the database id index for 64 bit variables.
117  * @count_64: number of usable 64 bit index entries
118  * @index_32: byte offset of the database id index for 32 bit variables.
119  * @count_32: number of usable 32 bit index entries
120  * @index_16: byte offset of the database id index for 16 bit variables.
121  * @count_16: number of usable 16 bit index entries
122  *
123  * Flash rom storage for exclusive use by guests running in the other os lpar.
124  * The current system configuration allocates 1K (two segments) for other os
125  * use.
126  */
127 
128 struct os_area_db {
129 	u8 magic_num[4];
130 	u16 version;
131 	u16 _reserved_1;
132 	u16 index_64;
133 	u16 count_64;
134 	u16 index_32;
135 	u16 count_32;
136 	u16 index_16;
137 	u16 count_16;
138 	u32 _reserved_2;
139 	u8 _db_data[1000];
140 };
141 
142 /**
143  * enum os_area_db_owner - Data owners.
144  */
145 
146 enum os_area_db_owner {
147 	OS_AREA_DB_OWNER_ANY = -1,
148 	OS_AREA_DB_OWNER_NONE = 0,
149 	OS_AREA_DB_OWNER_PROTOTYPE = 1,
150 	OS_AREA_DB_OWNER_LINUX = 2,
151 	OS_AREA_DB_OWNER_PETITBOOT = 3,
152 	OS_AREA_DB_OWNER_MAX = 32,
153 };
154 
155 enum os_area_db_key {
156 	OS_AREA_DB_KEY_ANY = -1,
157 	OS_AREA_DB_KEY_NONE = 0,
158 	OS_AREA_DB_KEY_RTC_DIFF = 1,
159 	OS_AREA_DB_KEY_VIDEO_MODE = 2,
160 	OS_AREA_DB_KEY_MAX = 8,
161 };
162 
163 struct os_area_db_id {
164 	int owner;
165 	int key;
166 };
167 
168 static const struct os_area_db_id os_area_db_id_empty = {
169 	.owner = OS_AREA_DB_OWNER_NONE,
170 	.key = OS_AREA_DB_KEY_NONE
171 };
172 
173 static const struct os_area_db_id os_area_db_id_any = {
174 	.owner = OS_AREA_DB_OWNER_ANY,
175 	.key = OS_AREA_DB_KEY_ANY
176 };
177 
178 static const struct os_area_db_id os_area_db_id_rtc_diff = {
179 	.owner = OS_AREA_DB_OWNER_LINUX,
180 	.key = OS_AREA_DB_KEY_RTC_DIFF
181 };
182 
183 #define SECONDS_FROM_1970_TO_2000 946684800LL
184 
185 /**
186  * struct saved_params - Static working copies of data from the PS3 'os area'.
187  *
188  * The order of preference we use for the rtc_diff source:
189  *  1) The database value.
190  *  2) The game os value.
191  *  3) The number of seconds from 1970 to 2000.
192  */
193 
194 static struct saved_params {
195 	unsigned int valid;
196 	s64 rtc_diff;
197 	unsigned int av_multi_out;
198 } saved_params;
199 
200 static struct property property_rtc_diff = {
201 	.name = "linux,rtc_diff",
202 	.length = sizeof(saved_params.rtc_diff),
203 	.value = &saved_params.rtc_diff,
204 };
205 
206 static struct property property_av_multi_out = {
207 	.name = "linux,av_multi_out",
208 	.length = sizeof(saved_params.av_multi_out),
209 	.value = &saved_params.av_multi_out,
210 };
211 
212 
213 static DEFINE_MUTEX(os_area_flash_mutex);
214 
215 static const struct ps3_os_area_flash_ops *os_area_flash_ops;
216 
ps3_os_area_flash_register(const struct ps3_os_area_flash_ops * ops)217 void ps3_os_area_flash_register(const struct ps3_os_area_flash_ops *ops)
218 {
219 	mutex_lock(&os_area_flash_mutex);
220 	os_area_flash_ops = ops;
221 	mutex_unlock(&os_area_flash_mutex);
222 }
223 EXPORT_SYMBOL_GPL(ps3_os_area_flash_register);
224 
os_area_flash_read(void * buf,size_t count,loff_t pos)225 static ssize_t os_area_flash_read(void *buf, size_t count, loff_t pos)
226 {
227 	ssize_t res = -ENODEV;
228 
229 	mutex_lock(&os_area_flash_mutex);
230 	if (os_area_flash_ops)
231 		res = os_area_flash_ops->read(buf, count, pos);
232 	mutex_unlock(&os_area_flash_mutex);
233 
234 	return res;
235 }
236 
os_area_flash_write(const void * buf,size_t count,loff_t pos)237 static ssize_t os_area_flash_write(const void *buf, size_t count, loff_t pos)
238 {
239 	ssize_t res = -ENODEV;
240 
241 	mutex_lock(&os_area_flash_mutex);
242 	if (os_area_flash_ops)
243 		res = os_area_flash_ops->write(buf, count, pos);
244 	mutex_unlock(&os_area_flash_mutex);
245 
246 	return res;
247 }
248 
249 
250 /**
251  * os_area_set_property - Add or overwrite a saved_params value to the device tree.
252  *
253  * Overwrites an existing property.
254  */
255 
os_area_set_property(struct device_node * node,struct property * prop)256 static void os_area_set_property(struct device_node *node,
257 	struct property *prop)
258 {
259 	int result;
260 	struct property *tmp = of_find_property(node, prop->name, NULL);
261 
262 	if (tmp) {
263 		pr_debug("%s:%d found %s\n", __func__, __LINE__, prop->name);
264 		of_remove_property(node, tmp);
265 	}
266 
267 	result = of_add_property(node, prop);
268 
269 	if (result)
270 		pr_debug("%s:%d of_set_property failed\n", __func__,
271 			__LINE__);
272 }
273 
274 /**
275  * os_area_get_property - Get a saved_params value from the device tree.
276  *
277  */
278 
os_area_get_property(struct device_node * node,struct property * prop)279 static void __init os_area_get_property(struct device_node *node,
280 	struct property *prop)
281 {
282 	const struct property *tmp = of_find_property(node, prop->name, NULL);
283 
284 	if (tmp) {
285 		BUG_ON(prop->length != tmp->length);
286 		memcpy(prop->value, tmp->value, prop->length);
287 	} else
288 		pr_debug("%s:%d not found %s\n", __func__, __LINE__,
289 			prop->name);
290 }
291 
dump_field(char * s,const u8 * field,int size_of_field)292 static void dump_field(char *s, const u8 *field, int size_of_field)
293 {
294 #if defined(DEBUG)
295 	int i;
296 
297 	for (i = 0; i < size_of_field; i++)
298 		s[i] = isprint(field[i]) ? field[i] : '.';
299 	s[i] = 0;
300 #endif
301 }
302 
303 #define dump_header(_a) _dump_header(_a, __func__, __LINE__)
_dump_header(const struct os_area_header * h,const char * func,int line)304 static void _dump_header(const struct os_area_header *h, const char *func,
305 	int line)
306 {
307 	char str[sizeof(h->magic_num) + 1];
308 
309 	dump_field(str, h->magic_num, sizeof(h->magic_num));
310 	pr_debug("%s:%d: h.magic_num:       '%s'\n", func, line,
311 		str);
312 	pr_debug("%s:%d: h.hdr_version:     %u\n", func, line,
313 		h->hdr_version);
314 	pr_debug("%s:%d: h.db_area_offset:  %u\n", func, line,
315 		h->db_area_offset);
316 	pr_debug("%s:%d: h.ldr_area_offset: %u\n", func, line,
317 		h->ldr_area_offset);
318 	pr_debug("%s:%d: h.ldr_format:      %u\n", func, line,
319 		h->ldr_format);
320 	pr_debug("%s:%d: h.ldr_size:        %xh\n", func, line,
321 		h->ldr_size);
322 }
323 
324 #define dump_params(_a) _dump_params(_a, __func__, __LINE__)
_dump_params(const struct os_area_params * p,const char * func,int line)325 static void _dump_params(const struct os_area_params *p, const char *func,
326 	int line)
327 {
328 	pr_debug("%s:%d: p.boot_flag:       %u\n", func, line, p->boot_flag);
329 	pr_debug("%s:%d: p.num_params:      %u\n", func, line, p->num_params);
330 	pr_debug("%s:%d: p.rtc_diff         %lld\n", func, line, p->rtc_diff);
331 	pr_debug("%s:%d: p.av_multi_out     %u\n", func, line, p->av_multi_out);
332 	pr_debug("%s:%d: p.ctrl_button:     %u\n", func, line, p->ctrl_button);
333 	pr_debug("%s:%d: p.static_ip_addr:  %u.%u.%u.%u\n", func, line,
334 		p->static_ip_addr[0], p->static_ip_addr[1],
335 		p->static_ip_addr[2], p->static_ip_addr[3]);
336 	pr_debug("%s:%d: p.network_mask:    %u.%u.%u.%u\n", func, line,
337 		p->network_mask[0], p->network_mask[1],
338 		p->network_mask[2], p->network_mask[3]);
339 	pr_debug("%s:%d: p.default_gateway: %u.%u.%u.%u\n", func, line,
340 		p->default_gateway[0], p->default_gateway[1],
341 		p->default_gateway[2], p->default_gateway[3]);
342 	pr_debug("%s:%d: p.dns_primary:     %u.%u.%u.%u\n", func, line,
343 		p->dns_primary[0], p->dns_primary[1],
344 		p->dns_primary[2], p->dns_primary[3]);
345 	pr_debug("%s:%d: p.dns_secondary:   %u.%u.%u.%u\n", func, line,
346 		p->dns_secondary[0], p->dns_secondary[1],
347 		p->dns_secondary[2], p->dns_secondary[3]);
348 }
349 
verify_header(const struct os_area_header * header)350 static int verify_header(const struct os_area_header *header)
351 {
352 	if (memcmp(header->magic_num, OS_AREA_HEADER_MAGIC_NUM,
353 		sizeof(header->magic_num))) {
354 		pr_debug("%s:%d magic_num failed\n", __func__, __LINE__);
355 		return -1;
356 	}
357 
358 	if (header->hdr_version < 1) {
359 		pr_debug("%s:%d hdr_version failed\n", __func__, __LINE__);
360 		return -1;
361 	}
362 
363 	if (header->db_area_offset > header->ldr_area_offset) {
364 		pr_debug("%s:%d offsets failed\n", __func__, __LINE__);
365 		return -1;
366 	}
367 
368 	return 0;
369 }
370 
db_verify(const struct os_area_db * db)371 static int db_verify(const struct os_area_db *db)
372 {
373 	if (memcmp(db->magic_num, OS_AREA_DB_MAGIC_NUM,
374 		sizeof(db->magic_num))) {
375 		pr_debug("%s:%d magic_num failed\n", __func__, __LINE__);
376 		return -EINVAL;
377 	}
378 
379 	if (db->version != 1) {
380 		pr_debug("%s:%d version failed\n", __func__, __LINE__);
381 		return -EINVAL;
382 	}
383 
384 	return 0;
385 }
386 
387 struct db_index {
388        uint8_t owner:5;
389        uint8_t key:3;
390 };
391 
392 struct db_iterator {
393 	const struct os_area_db *db;
394 	struct os_area_db_id match_id;
395 	struct db_index *idx;
396 	struct db_index *last_idx;
397 	union {
398 		uint64_t *value_64;
399 		uint32_t *value_32;
400 		uint16_t *value_16;
401 	};
402 };
403 
db_align_up(unsigned int val,unsigned int size)404 static unsigned int db_align_up(unsigned int val, unsigned int size)
405 {
406 	return (val + (size - 1)) & (~(size - 1));
407 }
408 
409 /**
410  * db_for_each_64 - Iterator for 64 bit entries.
411  *
412  * A NULL value for id can be used to match all entries.
413  * OS_AREA_DB_OWNER_ANY and OS_AREA_DB_KEY_ANY can be used to match all.
414  */
415 
db_for_each_64(const struct os_area_db * db,const struct os_area_db_id * match_id,struct db_iterator * i)416 static int db_for_each_64(const struct os_area_db *db,
417 	const struct os_area_db_id *match_id, struct db_iterator *i)
418 {
419 next:
420 	if (!i->db) {
421 		i->db = db;
422 		i->match_id = match_id ? *match_id : os_area_db_id_any;
423 		i->idx = (void *)db + db->index_64;
424 		i->last_idx = i->idx + db->count_64;
425 		i->value_64 = (void *)db + db->index_64
426 			+ db_align_up(db->count_64, 8);
427 	} else {
428 		i->idx++;
429 		i->value_64++;
430 	}
431 
432 	if (i->idx >= i->last_idx) {
433 		pr_debug("%s:%d: reached end\n", __func__, __LINE__);
434 		return 0;
435 	}
436 
437 	if (i->match_id.owner != OS_AREA_DB_OWNER_ANY
438 		&& i->match_id.owner != (int)i->idx->owner)
439 		goto next;
440 	if (i->match_id.key != OS_AREA_DB_KEY_ANY
441 		&& i->match_id.key != (int)i->idx->key)
442 		goto next;
443 
444 	return 1;
445 }
446 
db_delete_64(struct os_area_db * db,const struct os_area_db_id * id)447 static int db_delete_64(struct os_area_db *db, const struct os_area_db_id *id)
448 {
449 	struct db_iterator i;
450 
451 	for (i.db = NULL; db_for_each_64(db, id, &i); ) {
452 
453 		pr_debug("%s:%d: got (%d:%d) %llxh\n", __func__, __LINE__,
454 			i.idx->owner, i.idx->key,
455 			(unsigned long long)*i.value_64);
456 
457 		i.idx->owner = 0;
458 		i.idx->key = 0;
459 		*i.value_64 = 0;
460 	}
461 	return 0;
462 }
463 
db_set_64(struct os_area_db * db,const struct os_area_db_id * id,uint64_t value)464 static int db_set_64(struct os_area_db *db, const struct os_area_db_id *id,
465 	uint64_t value)
466 {
467 	struct db_iterator i;
468 
469 	pr_debug("%s:%d: (%d:%d) <= %llxh\n", __func__, __LINE__,
470 		id->owner, id->key, (unsigned long long)value);
471 
472 	if (!id->owner || id->owner == OS_AREA_DB_OWNER_ANY
473 		|| id->key == OS_AREA_DB_KEY_ANY) {
474 		pr_debug("%s:%d: bad id: (%d:%d)\n", __func__,
475 			__LINE__, id->owner, id->key);
476 		return -1;
477 	}
478 
479 	db_delete_64(db, id);
480 
481 	i.db = NULL;
482 	if (db_for_each_64(db, &os_area_db_id_empty, &i)) {
483 
484 		pr_debug("%s:%d: got (%d:%d) %llxh\n", __func__, __LINE__,
485 			i.idx->owner, i.idx->key,
486 			(unsigned long long)*i.value_64);
487 
488 		i.idx->owner = id->owner;
489 		i.idx->key = id->key;
490 		*i.value_64 = value;
491 
492 		pr_debug("%s:%d: set (%d:%d) <= %llxh\n", __func__, __LINE__,
493 			i.idx->owner, i.idx->key,
494 			(unsigned long long)*i.value_64);
495 		return 0;
496 	}
497 	pr_debug("%s:%d: database full.\n",
498 		__func__, __LINE__);
499 	return -1;
500 }
501 
db_get_64(const struct os_area_db * db,const struct os_area_db_id * id,uint64_t * value)502 static int __init db_get_64(const struct os_area_db *db,
503 	const struct os_area_db_id *id, uint64_t *value)
504 {
505 	struct db_iterator i;
506 
507 	i.db = NULL;
508 	if (db_for_each_64(db, id, &i)) {
509 		*value = *i.value_64;
510 		pr_debug("%s:%d: found %lld\n", __func__, __LINE__,
511 				(long long int)*i.value_64);
512 		return 0;
513 	}
514 	pr_debug("%s:%d: not found\n", __func__, __LINE__);
515 	return -1;
516 }
517 
db_get_rtc_diff(const struct os_area_db * db,int64_t * rtc_diff)518 static int __init db_get_rtc_diff(const struct os_area_db *db, int64_t *rtc_diff)
519 {
520 	return db_get_64(db, &os_area_db_id_rtc_diff, (uint64_t*)rtc_diff);
521 }
522 
523 #define dump_db(a) _dump_db(a, __func__, __LINE__)
_dump_db(const struct os_area_db * db,const char * func,int line)524 static void _dump_db(const struct os_area_db *db, const char *func,
525 	int line)
526 {
527 	char str[sizeof(db->magic_num) + 1];
528 
529 	dump_field(str, db->magic_num, sizeof(db->magic_num));
530 	pr_debug("%s:%d: db.magic_num:      '%s'\n", func, line,
531 		str);
532 	pr_debug("%s:%d: db.version:         %u\n", func, line,
533 		db->version);
534 	pr_debug("%s:%d: db.index_64:        %u\n", func, line,
535 		db->index_64);
536 	pr_debug("%s:%d: db.count_64:        %u\n", func, line,
537 		db->count_64);
538 	pr_debug("%s:%d: db.index_32:        %u\n", func, line,
539 		db->index_32);
540 	pr_debug("%s:%d: db.count_32:        %u\n", func, line,
541 		db->count_32);
542 	pr_debug("%s:%d: db.index_16:        %u\n", func, line,
543 		db->index_16);
544 	pr_debug("%s:%d: db.count_16:        %u\n", func, line,
545 		db->count_16);
546 }
547 
os_area_db_init(struct os_area_db * db)548 static void os_area_db_init(struct os_area_db *db)
549 {
550 	enum {
551 		HEADER_SIZE = offsetof(struct os_area_db, _db_data),
552 		INDEX_64_COUNT = 64,
553 		VALUES_64_COUNT = 57,
554 		INDEX_32_COUNT = 64,
555 		VALUES_32_COUNT = 57,
556 		INDEX_16_COUNT = 64,
557 		VALUES_16_COUNT = 57,
558 	};
559 
560 	memset(db, 0, sizeof(struct os_area_db));
561 
562 	memcpy(db->magic_num, OS_AREA_DB_MAGIC_NUM, sizeof(db->magic_num));
563 	db->version = 1;
564 	db->index_64 = HEADER_SIZE;
565 	db->count_64 = VALUES_64_COUNT;
566 	db->index_32 = HEADER_SIZE
567 			+ INDEX_64_COUNT * sizeof(struct db_index)
568 			+ VALUES_64_COUNT * sizeof(u64);
569 	db->count_32 = VALUES_32_COUNT;
570 	db->index_16 = HEADER_SIZE
571 			+ INDEX_64_COUNT * sizeof(struct db_index)
572 			+ VALUES_64_COUNT * sizeof(u64)
573 			+ INDEX_32_COUNT * sizeof(struct db_index)
574 			+ VALUES_32_COUNT * sizeof(u32);
575 	db->count_16 = VALUES_16_COUNT;
576 
577 	/* Rules to check db layout. */
578 
579 	BUILD_BUG_ON(sizeof(struct db_index) != 1);
580 	BUILD_BUG_ON(sizeof(struct os_area_db) != 2 * OS_AREA_SEGMENT_SIZE);
581 	BUILD_BUG_ON(INDEX_64_COUNT & 0x7);
582 	BUILD_BUG_ON(VALUES_64_COUNT > INDEX_64_COUNT);
583 	BUILD_BUG_ON(INDEX_32_COUNT & 0x7);
584 	BUILD_BUG_ON(VALUES_32_COUNT > INDEX_32_COUNT);
585 	BUILD_BUG_ON(INDEX_16_COUNT & 0x7);
586 	BUILD_BUG_ON(VALUES_16_COUNT > INDEX_16_COUNT);
587 	BUILD_BUG_ON(HEADER_SIZE
588 			+ INDEX_64_COUNT * sizeof(struct db_index)
589 			+ VALUES_64_COUNT * sizeof(u64)
590 			+ INDEX_32_COUNT * sizeof(struct db_index)
591 			+ VALUES_32_COUNT * sizeof(u32)
592 			+ INDEX_16_COUNT * sizeof(struct db_index)
593 			+ VALUES_16_COUNT * sizeof(u16)
594 			> sizeof(struct os_area_db));
595 }
596 
597 /**
598  * update_flash_db - Helper for os_area_queue_work_handler.
599  *
600  */
601 
update_flash_db(void)602 static int update_flash_db(void)
603 {
604 	const unsigned int buf_len = 8 * OS_AREA_SEGMENT_SIZE;
605 	struct os_area_header *header;
606 	ssize_t count;
607 	int error;
608 	loff_t pos;
609 	struct os_area_db* db;
610 
611 	/* Read in header and db from flash. */
612 
613 	header = kmalloc(buf_len, GFP_KERNEL);
614 	if (!header)
615 		return -ENOMEM;
616 
617 	count = os_area_flash_read(header, buf_len, 0);
618 	if (count < 0) {
619 		pr_debug("%s: os_area_flash_read failed %zd\n", __func__,
620 			 count);
621 		error = count;
622 		goto fail;
623 	}
624 
625 	pos = header->db_area_offset * OS_AREA_SEGMENT_SIZE;
626 	if (count < OS_AREA_SEGMENT_SIZE || verify_header(header) ||
627 	    count < pos) {
628 		pr_debug("%s: verify_header failed\n", __func__);
629 		dump_header(header);
630 		error = -EINVAL;
631 		goto fail;
632 	}
633 
634 	/* Now got a good db offset and some maybe good db data. */
635 
636 	db = (void *)header + pos;
637 
638 	error = db_verify(db);
639 	if (error) {
640 		pr_notice("%s: Verify of flash database failed, formatting.\n",
641 			  __func__);
642 		dump_db(db);
643 		os_area_db_init(db);
644 	}
645 
646 	/* Now got good db data. */
647 
648 	db_set_64(db, &os_area_db_id_rtc_diff, saved_params.rtc_diff);
649 
650 	count = os_area_flash_write(db, sizeof(struct os_area_db), pos);
651 	if (count < 0 || count < sizeof(struct os_area_db)) {
652 		pr_debug("%s: os_area_flash_write failed %zd\n", __func__,
653 			 count);
654 		error = count < 0 ? count : -EIO;
655 	}
656 
657 fail:
658 	kfree(header);
659 	return error;
660 }
661 
662 /**
663  * os_area_queue_work_handler - Asynchronous write handler.
664  *
665  * An asynchronous write for flash memory and the device tree.  Do not
666  * call directly, use os_area_queue_work().
667  */
668 
os_area_queue_work_handler(struct work_struct * work)669 static void os_area_queue_work_handler(struct work_struct *work)
670 {
671 	struct device_node *node;
672 	int error;
673 
674 	pr_debug(" -> %s:%d\n", __func__, __LINE__);
675 
676 	node = of_find_node_by_path("/");
677 	if (node) {
678 		os_area_set_property(node, &property_rtc_diff);
679 		of_node_put(node);
680 	} else
681 		pr_debug("%s:%d of_find_node_by_path failed\n",
682 			__func__, __LINE__);
683 
684 	error = update_flash_db();
685 	if (error)
686 		pr_warn("%s: Could not update FLASH ROM\n", __func__);
687 
688 	pr_debug(" <- %s:%d\n", __func__, __LINE__);
689 }
690 
os_area_queue_work(void)691 static void os_area_queue_work(void)
692 {
693 	static DECLARE_WORK(q, os_area_queue_work_handler);
694 
695 	wmb();
696 	schedule_work(&q);
697 }
698 
699 /**
700  * ps3_os_area_save_params - Copy data from os area mirror to @saved_params.
701  *
702  * For the convenience of the guest the HV makes a copy of the os area in
703  * flash to a high address in the boot memory region and then puts that RAM
704  * address and the byte count into the repository for retrieval by the guest.
705  * We copy the data we want into a static variable and allow the memory setup
706  * by the HV to be claimed by the memblock manager.
707  *
708  * The os area mirror will not be available to a second stage kernel, and
709  * the header verify will fail.  In this case, the saved_params values will
710  * be set from flash memory or the passed in device tree in ps3_os_area_init().
711  */
712 
ps3_os_area_save_params(void)713 void __init ps3_os_area_save_params(void)
714 {
715 	int result;
716 	u64 lpar_addr;
717 	unsigned int size;
718 	struct os_area_header *header;
719 	struct os_area_params *params;
720 	struct os_area_db *db;
721 
722 	pr_debug(" -> %s:%d\n", __func__, __LINE__);
723 
724 	result = ps3_repository_read_boot_dat_info(&lpar_addr, &size);
725 
726 	if (result) {
727 		pr_debug("%s:%d ps3_repository_read_boot_dat_info failed\n",
728 			__func__, __LINE__);
729 		return;
730 	}
731 
732 	header = (struct os_area_header *)__va(lpar_addr);
733 	params = (struct os_area_params *)__va(lpar_addr
734 		+ OS_AREA_SEGMENT_SIZE);
735 
736 	result = verify_header(header);
737 
738 	if (result) {
739 		/* Second stage kernels exit here. */
740 		pr_debug("%s:%d verify_header failed\n", __func__, __LINE__);
741 		dump_header(header);
742 		return;
743 	}
744 
745 	db = (struct os_area_db *)__va(lpar_addr
746 		+ header->db_area_offset * OS_AREA_SEGMENT_SIZE);
747 
748 	dump_header(header);
749 	dump_params(params);
750 	dump_db(db);
751 
752 	result = db_verify(db) || db_get_rtc_diff(db, &saved_params.rtc_diff);
753 	if (result)
754 		saved_params.rtc_diff = params->rtc_diff ? params->rtc_diff
755 			: SECONDS_FROM_1970_TO_2000;
756 	saved_params.av_multi_out = params->av_multi_out;
757 	saved_params.valid = 1;
758 
759 	memset(header, 0, sizeof(*header));
760 
761 	pr_debug(" <- %s:%d\n", __func__, __LINE__);
762 }
763 
764 /**
765  * ps3_os_area_init - Setup os area device tree properties as needed.
766  */
767 
ps3_os_area_init(void)768 void __init ps3_os_area_init(void)
769 {
770 	struct device_node *node;
771 
772 	pr_debug(" -> %s:%d\n", __func__, __LINE__);
773 
774 	node = of_find_node_by_path("/");
775 
776 	if (!saved_params.valid && node) {
777 		/* Second stage kernels should have a dt entry. */
778 		os_area_get_property(node, &property_rtc_diff);
779 		os_area_get_property(node, &property_av_multi_out);
780 	}
781 
782 	if(!saved_params.rtc_diff)
783 		saved_params.rtc_diff = SECONDS_FROM_1970_TO_2000;
784 
785 	if (node) {
786 		os_area_set_property(node, &property_rtc_diff);
787 		os_area_set_property(node, &property_av_multi_out);
788 		of_node_put(node);
789 	} else
790 		pr_debug("%s:%d of_find_node_by_path failed\n",
791 			__func__, __LINE__);
792 
793 	pr_debug(" <- %s:%d\n", __func__, __LINE__);
794 }
795 
796 /**
797  * ps3_os_area_get_rtc_diff - Returns the rtc diff value.
798  */
799 
ps3_os_area_get_rtc_diff(void)800 u64 ps3_os_area_get_rtc_diff(void)
801 {
802 	return saved_params.rtc_diff;
803 }
804 EXPORT_SYMBOL_GPL(ps3_os_area_get_rtc_diff);
805 
806 /**
807  * ps3_os_area_set_rtc_diff - Set the rtc diff value.
808  *
809  * An asynchronous write is needed to support writing updates from
810  * the timer interrupt context.
811  */
812 
ps3_os_area_set_rtc_diff(u64 rtc_diff)813 void ps3_os_area_set_rtc_diff(u64 rtc_diff)
814 {
815 	if (saved_params.rtc_diff != rtc_diff) {
816 		saved_params.rtc_diff = rtc_diff;
817 		os_area_queue_work();
818 	}
819 }
820 EXPORT_SYMBOL_GPL(ps3_os_area_set_rtc_diff);
821 
822 /**
823  * ps3_os_area_get_av_multi_out - Returns the default video mode.
824  */
825 
ps3_os_area_get_av_multi_out(void)826 enum ps3_param_av_multi_out ps3_os_area_get_av_multi_out(void)
827 {
828     return saved_params.av_multi_out;
829 }
830 EXPORT_SYMBOL_GPL(ps3_os_area_get_av_multi_out);
831