1 /*
2  * NAND flash simulator.
3  *
4  * Author: Artem B. Bityuckiy <dedekind@oktetlabs.ru>, <dedekind@infradead.org>
5  *
6  * Copyright (C) 2004 Nokia Corporation
7  *
8  * Note: NS means "NAND Simulator".
9  * Note: Input means input TO flash chip, output means output FROM chip.
10  *
11  * This program is free software; you can redistribute it and/or modify it
12  * under the terms of the GNU General Public License as published by the
13  * Free Software Foundation; either version 2, or (at your option) any later
14  * version.
15  *
16  * This program is distributed in the hope that it will be useful, but
17  * WITHOUT ANY WARRANTY; without even the implied warranty of
18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
19  * Public License for more details.
20  *
21  * You should have received a copy of the GNU General Public License
22  * along with this program; if not, write to the Free Software
23  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA
24  */
25 
26 #include <linux/init.h>
27 #include <linux/types.h>
28 #include <linux/module.h>
29 #include <linux/moduleparam.h>
30 #include <linux/vmalloc.h>
31 #include <asm/div64.h>
32 #include <linux/slab.h>
33 #include <linux/errno.h>
34 #include <linux/string.h>
35 #include <linux/mtd/mtd.h>
36 #include <linux/mtd/nand.h>
37 #include <linux/mtd/nand_bch.h>
38 #include <linux/mtd/partitions.h>
39 #include <linux/delay.h>
40 #include <linux/list.h>
41 #include <linux/random.h>
42 #include <linux/sched.h>
43 #include <linux/fs.h>
44 #include <linux/pagemap.h>
45 
46 /* Default simulator parameters values */
47 #if !defined(CONFIG_NANDSIM_FIRST_ID_BYTE)  || \
48     !defined(CONFIG_NANDSIM_SECOND_ID_BYTE) || \
49     !defined(CONFIG_NANDSIM_THIRD_ID_BYTE)  || \
50     !defined(CONFIG_NANDSIM_FOURTH_ID_BYTE)
51 #define CONFIG_NANDSIM_FIRST_ID_BYTE  0x98
52 #define CONFIG_NANDSIM_SECOND_ID_BYTE 0x39
53 #define CONFIG_NANDSIM_THIRD_ID_BYTE  0xFF /* No byte */
54 #define CONFIG_NANDSIM_FOURTH_ID_BYTE 0xFF /* No byte */
55 #endif
56 
57 #ifndef CONFIG_NANDSIM_ACCESS_DELAY
58 #define CONFIG_NANDSIM_ACCESS_DELAY 25
59 #endif
60 #ifndef CONFIG_NANDSIM_PROGRAMM_DELAY
61 #define CONFIG_NANDSIM_PROGRAMM_DELAY 200
62 #endif
63 #ifndef CONFIG_NANDSIM_ERASE_DELAY
64 #define CONFIG_NANDSIM_ERASE_DELAY 2
65 #endif
66 #ifndef CONFIG_NANDSIM_OUTPUT_CYCLE
67 #define CONFIG_NANDSIM_OUTPUT_CYCLE 40
68 #endif
69 #ifndef CONFIG_NANDSIM_INPUT_CYCLE
70 #define CONFIG_NANDSIM_INPUT_CYCLE  50
71 #endif
72 #ifndef CONFIG_NANDSIM_BUS_WIDTH
73 #define CONFIG_NANDSIM_BUS_WIDTH  8
74 #endif
75 #ifndef CONFIG_NANDSIM_DO_DELAYS
76 #define CONFIG_NANDSIM_DO_DELAYS  0
77 #endif
78 #ifndef CONFIG_NANDSIM_LOG
79 #define CONFIG_NANDSIM_LOG        0
80 #endif
81 #ifndef CONFIG_NANDSIM_DBG
82 #define CONFIG_NANDSIM_DBG        0
83 #endif
84 #ifndef CONFIG_NANDSIM_MAX_PARTS
85 #define CONFIG_NANDSIM_MAX_PARTS  32
86 #endif
87 
88 static uint first_id_byte  = CONFIG_NANDSIM_FIRST_ID_BYTE;
89 static uint second_id_byte = CONFIG_NANDSIM_SECOND_ID_BYTE;
90 static uint third_id_byte  = CONFIG_NANDSIM_THIRD_ID_BYTE;
91 static uint fourth_id_byte = CONFIG_NANDSIM_FOURTH_ID_BYTE;
92 static uint access_delay   = CONFIG_NANDSIM_ACCESS_DELAY;
93 static uint programm_delay = CONFIG_NANDSIM_PROGRAMM_DELAY;
94 static uint erase_delay    = CONFIG_NANDSIM_ERASE_DELAY;
95 static uint output_cycle   = CONFIG_NANDSIM_OUTPUT_CYCLE;
96 static uint input_cycle    = CONFIG_NANDSIM_INPUT_CYCLE;
97 static uint bus_width      = CONFIG_NANDSIM_BUS_WIDTH;
98 static uint do_delays      = CONFIG_NANDSIM_DO_DELAYS;
99 static uint log            = CONFIG_NANDSIM_LOG;
100 static uint dbg            = CONFIG_NANDSIM_DBG;
101 static unsigned long parts[CONFIG_NANDSIM_MAX_PARTS];
102 static unsigned int parts_num;
103 static char *badblocks = NULL;
104 static char *weakblocks = NULL;
105 static char *weakpages = NULL;
106 static unsigned int bitflips = 0;
107 static char *gravepages = NULL;
108 static unsigned int rptwear = 0;
109 static unsigned int overridesize = 0;
110 static char *cache_file = NULL;
111 static unsigned int bbt;
112 static unsigned int bch;
113 
114 module_param(first_id_byte,  uint, 0400);
115 module_param(second_id_byte, uint, 0400);
116 module_param(third_id_byte,  uint, 0400);
117 module_param(fourth_id_byte, uint, 0400);
118 module_param(access_delay,   uint, 0400);
119 module_param(programm_delay, uint, 0400);
120 module_param(erase_delay,    uint, 0400);
121 module_param(output_cycle,   uint, 0400);
122 module_param(input_cycle,    uint, 0400);
123 module_param(bus_width,      uint, 0400);
124 module_param(do_delays,      uint, 0400);
125 module_param(log,            uint, 0400);
126 module_param(dbg,            uint, 0400);
127 module_param_array(parts, ulong, &parts_num, 0400);
128 module_param(badblocks,      charp, 0400);
129 module_param(weakblocks,     charp, 0400);
130 module_param(weakpages,      charp, 0400);
131 module_param(bitflips,       uint, 0400);
132 module_param(gravepages,     charp, 0400);
133 module_param(rptwear,        uint, 0400);
134 module_param(overridesize,   uint, 0400);
135 module_param(cache_file,     charp, 0400);
136 module_param(bbt,	     uint, 0400);
137 module_param(bch,	     uint, 0400);
138 
139 MODULE_PARM_DESC(first_id_byte,  "The first byte returned by NAND Flash 'read ID' command (manufacturer ID)");
140 MODULE_PARM_DESC(second_id_byte, "The second byte returned by NAND Flash 'read ID' command (chip ID)");
141 MODULE_PARM_DESC(third_id_byte,  "The third byte returned by NAND Flash 'read ID' command");
142 MODULE_PARM_DESC(fourth_id_byte, "The fourth byte returned by NAND Flash 'read ID' command");
143 MODULE_PARM_DESC(access_delay,   "Initial page access delay (microseconds)");
144 MODULE_PARM_DESC(programm_delay, "Page programm delay (microseconds");
145 MODULE_PARM_DESC(erase_delay,    "Sector erase delay (milliseconds)");
146 MODULE_PARM_DESC(output_cycle,   "Word output (from flash) time (nanoseconds)");
147 MODULE_PARM_DESC(input_cycle,    "Word input (to flash) time (nanoseconds)");
148 MODULE_PARM_DESC(bus_width,      "Chip's bus width (8- or 16-bit)");
149 MODULE_PARM_DESC(do_delays,      "Simulate NAND delays using busy-waits if not zero");
150 MODULE_PARM_DESC(log,            "Perform logging if not zero");
151 MODULE_PARM_DESC(dbg,            "Output debug information if not zero");
152 MODULE_PARM_DESC(parts,          "Partition sizes (in erase blocks) separated by commas");
153 /* Page and erase block positions for the following parameters are independent of any partitions */
154 MODULE_PARM_DESC(badblocks,      "Erase blocks that are initially marked bad, separated by commas");
155 MODULE_PARM_DESC(weakblocks,     "Weak erase blocks [: remaining erase cycles (defaults to 3)]"
156 				 " separated by commas e.g. 113:2 means eb 113"
157 				 " can be erased only twice before failing");
158 MODULE_PARM_DESC(weakpages,      "Weak pages [: maximum writes (defaults to 3)]"
159 				 " separated by commas e.g. 1401:2 means page 1401"
160 				 " can be written only twice before failing");
161 MODULE_PARM_DESC(bitflips,       "Maximum number of random bit flips per page (zero by default)");
162 MODULE_PARM_DESC(gravepages,     "Pages that lose data [: maximum reads (defaults to 3)]"
163 				 " separated by commas e.g. 1401:2 means page 1401"
164 				 " can be read only twice before failing");
165 MODULE_PARM_DESC(rptwear,        "Number of erases between reporting wear, if not zero");
166 MODULE_PARM_DESC(overridesize,   "Specifies the NAND Flash size overriding the ID bytes. "
167 				 "The size is specified in erase blocks and as the exponent of a power of two"
168 				 " e.g. 5 means a size of 32 erase blocks");
169 MODULE_PARM_DESC(cache_file,     "File to use to cache nand pages instead of memory");
170 MODULE_PARM_DESC(bbt,		 "0 OOB, 1 BBT with marker in OOB, 2 BBT with marker in data area");
171 MODULE_PARM_DESC(bch,		 "Enable BCH ecc and set how many bits should "
172 				 "be correctable in 512-byte blocks");
173 
174 /* The largest possible page size */
175 #define NS_LARGEST_PAGE_SIZE	4096
176 
177 /* The prefix for simulator output */
178 #define NS_OUTPUT_PREFIX "[nandsim]"
179 
180 /* Simulator's output macros (logging, debugging, warning, error) */
181 #define NS_LOG(args...) \
182 	do { if (log) printk(KERN_DEBUG NS_OUTPUT_PREFIX " log: " args); } while(0)
183 #define NS_DBG(args...) \
184 	do { if (dbg) printk(KERN_DEBUG NS_OUTPUT_PREFIX " debug: " args); } while(0)
185 #define NS_WARN(args...) \
186 	do { printk(KERN_WARNING NS_OUTPUT_PREFIX " warning: " args); } while(0)
187 #define NS_ERR(args...) \
188 	do { printk(KERN_ERR NS_OUTPUT_PREFIX " error: " args); } while(0)
189 #define NS_INFO(args...) \
190 	do { printk(KERN_INFO NS_OUTPUT_PREFIX " " args); } while(0)
191 
192 /* Busy-wait delay macros (microseconds, milliseconds) */
193 #define NS_UDELAY(us) \
194         do { if (do_delays) udelay(us); } while(0)
195 #define NS_MDELAY(us) \
196         do { if (do_delays) mdelay(us); } while(0)
197 
198 /* Is the nandsim structure initialized ? */
199 #define NS_IS_INITIALIZED(ns) ((ns)->geom.totsz != 0)
200 
201 /* Good operation completion status */
202 #define NS_STATUS_OK(ns) (NAND_STATUS_READY | (NAND_STATUS_WP * ((ns)->lines.wp == 0)))
203 
204 /* Operation failed completion status */
205 #define NS_STATUS_FAILED(ns) (NAND_STATUS_FAIL | NS_STATUS_OK(ns))
206 
207 /* Calculate the page offset in flash RAM image by (row, column) address */
208 #define NS_RAW_OFFSET(ns) \
209 	(((ns)->regs.row << (ns)->geom.pgshift) + ((ns)->regs.row * (ns)->geom.oobsz) + (ns)->regs.column)
210 
211 /* Calculate the OOB offset in flash RAM image by (row, column) address */
212 #define NS_RAW_OFFSET_OOB(ns) (NS_RAW_OFFSET(ns) + ns->geom.pgsz)
213 
214 /* After a command is input, the simulator goes to one of the following states */
215 #define STATE_CMD_READ0        0x00000001 /* read data from the beginning of page */
216 #define STATE_CMD_READ1        0x00000002 /* read data from the second half of page */
217 #define STATE_CMD_READSTART    0x00000003 /* read data second command (large page devices) */
218 #define STATE_CMD_PAGEPROG     0x00000004 /* start page program */
219 #define STATE_CMD_READOOB      0x00000005 /* read OOB area */
220 #define STATE_CMD_ERASE1       0x00000006 /* sector erase first command */
221 #define STATE_CMD_STATUS       0x00000007 /* read status */
222 #define STATE_CMD_STATUS_M     0x00000008 /* read multi-plane status (isn't implemented) */
223 #define STATE_CMD_SEQIN        0x00000009 /* sequential data input */
224 #define STATE_CMD_READID       0x0000000A /* read ID */
225 #define STATE_CMD_ERASE2       0x0000000B /* sector erase second command */
226 #define STATE_CMD_RESET        0x0000000C /* reset */
227 #define STATE_CMD_RNDOUT       0x0000000D /* random output command */
228 #define STATE_CMD_RNDOUTSTART  0x0000000E /* random output start command */
229 #define STATE_CMD_MASK         0x0000000F /* command states mask */
230 
231 /* After an address is input, the simulator goes to one of these states */
232 #define STATE_ADDR_PAGE        0x00000010 /* full (row, column) address is accepted */
233 #define STATE_ADDR_SEC         0x00000020 /* sector address was accepted */
234 #define STATE_ADDR_COLUMN      0x00000030 /* column address was accepted */
235 #define STATE_ADDR_ZERO        0x00000040 /* one byte zero address was accepted */
236 #define STATE_ADDR_MASK        0x00000070 /* address states mask */
237 
238 /* During data input/output the simulator is in these states */
239 #define STATE_DATAIN           0x00000100 /* waiting for data input */
240 #define STATE_DATAIN_MASK      0x00000100 /* data input states mask */
241 
242 #define STATE_DATAOUT          0x00001000 /* waiting for page data output */
243 #define STATE_DATAOUT_ID       0x00002000 /* waiting for ID bytes output */
244 #define STATE_DATAOUT_STATUS   0x00003000 /* waiting for status output */
245 #define STATE_DATAOUT_STATUS_M 0x00004000 /* waiting for multi-plane status output */
246 #define STATE_DATAOUT_MASK     0x00007000 /* data output states mask */
247 
248 /* Previous operation is done, ready to accept new requests */
249 #define STATE_READY            0x00000000
250 
251 /* This state is used to mark that the next state isn't known yet */
252 #define STATE_UNKNOWN          0x10000000
253 
254 /* Simulator's actions bit masks */
255 #define ACTION_CPY       0x00100000 /* copy page/OOB to the internal buffer */
256 #define ACTION_PRGPAGE   0x00200000 /* program the internal buffer to flash */
257 #define ACTION_SECERASE  0x00300000 /* erase sector */
258 #define ACTION_ZEROOFF   0x00400000 /* don't add any offset to address */
259 #define ACTION_HALFOFF   0x00500000 /* add to address half of page */
260 #define ACTION_OOBOFF    0x00600000 /* add to address OOB offset */
261 #define ACTION_MASK      0x00700000 /* action mask */
262 
263 #define NS_OPER_NUM      13 /* Number of operations supported by the simulator */
264 #define NS_OPER_STATES   6  /* Maximum number of states in operation */
265 
266 #define OPT_ANY          0xFFFFFFFF /* any chip supports this operation */
267 #define OPT_PAGE256      0x00000001 /* 256-byte  page chips */
268 #define OPT_PAGE512      0x00000002 /* 512-byte  page chips */
269 #define OPT_PAGE2048     0x00000008 /* 2048-byte page chips */
270 #define OPT_SMARTMEDIA   0x00000010 /* SmartMedia technology chips */
271 #define OPT_AUTOINCR     0x00000020 /* page number auto incrementation is possible */
272 #define OPT_PAGE512_8BIT 0x00000040 /* 512-byte page chips with 8-bit bus width */
273 #define OPT_PAGE4096     0x00000080 /* 4096-byte page chips */
274 #define OPT_LARGEPAGE    (OPT_PAGE2048 | OPT_PAGE4096) /* 2048 & 4096-byte page chips */
275 #define OPT_SMALLPAGE    (OPT_PAGE256  | OPT_PAGE512)  /* 256 and 512-byte page chips */
276 
277 /* Remove action bits from state */
278 #define NS_STATE(x) ((x) & ~ACTION_MASK)
279 
280 /*
281  * Maximum previous states which need to be saved. Currently saving is
282  * only needed for page program operation with preceded read command
283  * (which is only valid for 512-byte pages).
284  */
285 #define NS_MAX_PREVSTATES 1
286 
287 /* Maximum page cache pages needed to read or write a NAND page to the cache_file */
288 #define NS_MAX_HELD_PAGES 16
289 
290 /*
291  * A union to represent flash memory contents and flash buffer.
292  */
293 union ns_mem {
294 	u_char *byte;    /* for byte access */
295 	uint16_t *word;  /* for 16-bit word access */
296 };
297 
298 /*
299  * The structure which describes all the internal simulator data.
300  */
301 struct nandsim {
302 	struct mtd_partition partitions[CONFIG_NANDSIM_MAX_PARTS];
303 	unsigned int nbparts;
304 
305 	uint busw;              /* flash chip bus width (8 or 16) */
306 	u_char ids[4];          /* chip's ID bytes */
307 	uint32_t options;       /* chip's characteristic bits */
308 	uint32_t state;         /* current chip state */
309 	uint32_t nxstate;       /* next expected state */
310 
311 	uint32_t *op;           /* current operation, NULL operations isn't known yet  */
312 	uint32_t pstates[NS_MAX_PREVSTATES]; /* previous states */
313 	uint16_t npstates;      /* number of previous states saved */
314 	uint16_t stateidx;      /* current state index */
315 
316 	/* The simulated NAND flash pages array */
317 	union ns_mem *pages;
318 
319 	/* Slab allocator for nand pages */
320 	struct kmem_cache *nand_pages_slab;
321 
322 	/* Internal buffer of page + OOB size bytes */
323 	union ns_mem buf;
324 
325 	/* NAND flash "geometry" */
326 	struct {
327 		uint64_t totsz;     /* total flash size, bytes */
328 		uint32_t secsz;     /* flash sector (erase block) size, bytes */
329 		uint pgsz;          /* NAND flash page size, bytes */
330 		uint oobsz;         /* page OOB area size, bytes */
331 		uint64_t totszoob;  /* total flash size including OOB, bytes */
332 		uint pgszoob;       /* page size including OOB , bytes*/
333 		uint secszoob;      /* sector size including OOB, bytes */
334 		uint pgnum;         /* total number of pages */
335 		uint pgsec;         /* number of pages per sector */
336 		uint secshift;      /* bits number in sector size */
337 		uint pgshift;       /* bits number in page size */
338 		uint oobshift;      /* bits number in OOB size */
339 		uint pgaddrbytes;   /* bytes per page address */
340 		uint secaddrbytes;  /* bytes per sector address */
341 		uint idbytes;       /* the number ID bytes that this chip outputs */
342 	} geom;
343 
344 	/* NAND flash internal registers */
345 	struct {
346 		unsigned command; /* the command register */
347 		u_char   status;  /* the status register */
348 		uint     row;     /* the page number */
349 		uint     column;  /* the offset within page */
350 		uint     count;   /* internal counter */
351 		uint     num;     /* number of bytes which must be processed */
352 		uint     off;     /* fixed page offset */
353 	} regs;
354 
355 	/* NAND flash lines state */
356         struct {
357                 int ce;  /* chip Enable */
358                 int cle; /* command Latch Enable */
359                 int ale; /* address Latch Enable */
360                 int wp;  /* write Protect */
361         } lines;
362 
363 	/* Fields needed when using a cache file */
364 	struct file *cfile; /* Open file */
365 	unsigned char *pages_written; /* Which pages have been written */
366 	void *file_buf;
367 	struct page *held_pages[NS_MAX_HELD_PAGES];
368 	int held_cnt;
369 };
370 
371 /*
372  * Operations array. To perform any operation the simulator must pass
373  * through the correspondent states chain.
374  */
375 static struct nandsim_operations {
376 	uint32_t reqopts;  /* options which are required to perform the operation */
377 	uint32_t states[NS_OPER_STATES]; /* operation's states */
378 } ops[NS_OPER_NUM] = {
379 	/* Read page + OOB from the beginning */
380 	{OPT_SMALLPAGE, {STATE_CMD_READ0 | ACTION_ZEROOFF, STATE_ADDR_PAGE | ACTION_CPY,
381 			STATE_DATAOUT, STATE_READY}},
382 	/* Read page + OOB from the second half */
383 	{OPT_PAGE512_8BIT, {STATE_CMD_READ1 | ACTION_HALFOFF, STATE_ADDR_PAGE | ACTION_CPY,
384 			STATE_DATAOUT, STATE_READY}},
385 	/* Read OOB */
386 	{OPT_SMALLPAGE, {STATE_CMD_READOOB | ACTION_OOBOFF, STATE_ADDR_PAGE | ACTION_CPY,
387 			STATE_DATAOUT, STATE_READY}},
388 	/* Program page starting from the beginning */
389 	{OPT_ANY, {STATE_CMD_SEQIN, STATE_ADDR_PAGE, STATE_DATAIN,
390 			STATE_CMD_PAGEPROG | ACTION_PRGPAGE, STATE_READY}},
391 	/* Program page starting from the beginning */
392 	{OPT_SMALLPAGE, {STATE_CMD_READ0, STATE_CMD_SEQIN | ACTION_ZEROOFF, STATE_ADDR_PAGE,
393 			      STATE_DATAIN, STATE_CMD_PAGEPROG | ACTION_PRGPAGE, STATE_READY}},
394 	/* Program page starting from the second half */
395 	{OPT_PAGE512, {STATE_CMD_READ1, STATE_CMD_SEQIN | ACTION_HALFOFF, STATE_ADDR_PAGE,
396 			      STATE_DATAIN, STATE_CMD_PAGEPROG | ACTION_PRGPAGE, STATE_READY}},
397 	/* Program OOB */
398 	{OPT_SMALLPAGE, {STATE_CMD_READOOB, STATE_CMD_SEQIN | ACTION_OOBOFF, STATE_ADDR_PAGE,
399 			      STATE_DATAIN, STATE_CMD_PAGEPROG | ACTION_PRGPAGE, STATE_READY}},
400 	/* Erase sector */
401 	{OPT_ANY, {STATE_CMD_ERASE1, STATE_ADDR_SEC, STATE_CMD_ERASE2 | ACTION_SECERASE, STATE_READY}},
402 	/* Read status */
403 	{OPT_ANY, {STATE_CMD_STATUS, STATE_DATAOUT_STATUS, STATE_READY}},
404 	/* Read multi-plane status */
405 	{OPT_SMARTMEDIA, {STATE_CMD_STATUS_M, STATE_DATAOUT_STATUS_M, STATE_READY}},
406 	/* Read ID */
407 	{OPT_ANY, {STATE_CMD_READID, STATE_ADDR_ZERO, STATE_DATAOUT_ID, STATE_READY}},
408 	/* Large page devices read page */
409 	{OPT_LARGEPAGE, {STATE_CMD_READ0, STATE_ADDR_PAGE, STATE_CMD_READSTART | ACTION_CPY,
410 			       STATE_DATAOUT, STATE_READY}},
411 	/* Large page devices random page read */
412 	{OPT_LARGEPAGE, {STATE_CMD_RNDOUT, STATE_ADDR_COLUMN, STATE_CMD_RNDOUTSTART | ACTION_CPY,
413 			       STATE_DATAOUT, STATE_READY}},
414 };
415 
416 struct weak_block {
417 	struct list_head list;
418 	unsigned int erase_block_no;
419 	unsigned int max_erases;
420 	unsigned int erases_done;
421 };
422 
423 static LIST_HEAD(weak_blocks);
424 
425 struct weak_page {
426 	struct list_head list;
427 	unsigned int page_no;
428 	unsigned int max_writes;
429 	unsigned int writes_done;
430 };
431 
432 static LIST_HEAD(weak_pages);
433 
434 struct grave_page {
435 	struct list_head list;
436 	unsigned int page_no;
437 	unsigned int max_reads;
438 	unsigned int reads_done;
439 };
440 
441 static LIST_HEAD(grave_pages);
442 
443 static unsigned long *erase_block_wear = NULL;
444 static unsigned int wear_eb_count = 0;
445 static unsigned long total_wear = 0;
446 static unsigned int rptwear_cnt = 0;
447 
448 /* MTD structure for NAND controller */
449 static struct mtd_info *nsmtd;
450 
451 static u_char ns_verify_buf[NS_LARGEST_PAGE_SIZE];
452 
453 /*
454  * Allocate array of page pointers, create slab allocation for an array
455  * and initialize the array by NULL pointers.
456  *
457  * RETURNS: 0 if success, -ENOMEM if memory alloc fails.
458  */
alloc_device(struct nandsim * ns)459 static int alloc_device(struct nandsim *ns)
460 {
461 	struct file *cfile;
462 	int i, err;
463 
464 	if (cache_file) {
465 		cfile = filp_open(cache_file, O_CREAT | O_RDWR | O_LARGEFILE, 0600);
466 		if (IS_ERR(cfile))
467 			return PTR_ERR(cfile);
468 		if (!cfile->f_op || (!cfile->f_op->read && !cfile->f_op->aio_read)) {
469 			NS_ERR("alloc_device: cache file not readable\n");
470 			err = -EINVAL;
471 			goto err_close;
472 		}
473 		if (!cfile->f_op->write && !cfile->f_op->aio_write) {
474 			NS_ERR("alloc_device: cache file not writeable\n");
475 			err = -EINVAL;
476 			goto err_close;
477 		}
478 		ns->pages_written = vzalloc(ns->geom.pgnum);
479 		if (!ns->pages_written) {
480 			NS_ERR("alloc_device: unable to allocate pages written array\n");
481 			err = -ENOMEM;
482 			goto err_close;
483 		}
484 		ns->file_buf = kmalloc(ns->geom.pgszoob, GFP_KERNEL);
485 		if (!ns->file_buf) {
486 			NS_ERR("alloc_device: unable to allocate file buf\n");
487 			err = -ENOMEM;
488 			goto err_free;
489 		}
490 		ns->cfile = cfile;
491 		return 0;
492 	}
493 
494 	ns->pages = vmalloc(ns->geom.pgnum * sizeof(union ns_mem));
495 	if (!ns->pages) {
496 		NS_ERR("alloc_device: unable to allocate page array\n");
497 		return -ENOMEM;
498 	}
499 	for (i = 0; i < ns->geom.pgnum; i++) {
500 		ns->pages[i].byte = NULL;
501 	}
502 	ns->nand_pages_slab = kmem_cache_create("nandsim",
503 						ns->geom.pgszoob, 0, 0, NULL);
504 	if (!ns->nand_pages_slab) {
505 		NS_ERR("cache_create: unable to create kmem_cache\n");
506 		return -ENOMEM;
507 	}
508 
509 	return 0;
510 
511 err_free:
512 	vfree(ns->pages_written);
513 err_close:
514 	filp_close(cfile, NULL);
515 	return err;
516 }
517 
518 /*
519  * Free any allocated pages, and free the array of page pointers.
520  */
free_device(struct nandsim * ns)521 static void free_device(struct nandsim *ns)
522 {
523 	int i;
524 
525 	if (ns->cfile) {
526 		kfree(ns->file_buf);
527 		vfree(ns->pages_written);
528 		filp_close(ns->cfile, NULL);
529 		return;
530 	}
531 
532 	if (ns->pages) {
533 		for (i = 0; i < ns->geom.pgnum; i++) {
534 			if (ns->pages[i].byte)
535 				kmem_cache_free(ns->nand_pages_slab,
536 						ns->pages[i].byte);
537 		}
538 		kmem_cache_destroy(ns->nand_pages_slab);
539 		vfree(ns->pages);
540 	}
541 }
542 
get_partition_name(int i)543 static char *get_partition_name(int i)
544 {
545 	char buf[64];
546 	sprintf(buf, "NAND simulator partition %d", i);
547 	return kstrdup(buf, GFP_KERNEL);
548 }
549 
divide(uint64_t n,uint32_t d)550 static uint64_t divide(uint64_t n, uint32_t d)
551 {
552 	do_div(n, d);
553 	return n;
554 }
555 
556 /*
557  * Initialize the nandsim structure.
558  *
559  * RETURNS: 0 if success, -ERRNO if failure.
560  */
init_nandsim(struct mtd_info * mtd)561 static int init_nandsim(struct mtd_info *mtd)
562 {
563 	struct nand_chip *chip = mtd->priv;
564 	struct nandsim   *ns   = chip->priv;
565 	int i, ret = 0;
566 	uint64_t remains;
567 	uint64_t next_offset;
568 
569 	if (NS_IS_INITIALIZED(ns)) {
570 		NS_ERR("init_nandsim: nandsim is already initialized\n");
571 		return -EIO;
572 	}
573 
574 	/* Force mtd to not do delays */
575 	chip->chip_delay = 0;
576 
577 	/* Initialize the NAND flash parameters */
578 	ns->busw = chip->options & NAND_BUSWIDTH_16 ? 16 : 8;
579 	ns->geom.totsz    = mtd->size;
580 	ns->geom.pgsz     = mtd->writesize;
581 	ns->geom.oobsz    = mtd->oobsize;
582 	ns->geom.secsz    = mtd->erasesize;
583 	ns->geom.pgszoob  = ns->geom.pgsz + ns->geom.oobsz;
584 	ns->geom.pgnum    = divide(ns->geom.totsz, ns->geom.pgsz);
585 	ns->geom.totszoob = ns->geom.totsz + (uint64_t)ns->geom.pgnum * ns->geom.oobsz;
586 	ns->geom.secshift = ffs(ns->geom.secsz) - 1;
587 	ns->geom.pgshift  = chip->page_shift;
588 	ns->geom.oobshift = ffs(ns->geom.oobsz) - 1;
589 	ns->geom.pgsec    = ns->geom.secsz / ns->geom.pgsz;
590 	ns->geom.secszoob = ns->geom.secsz + ns->geom.oobsz * ns->geom.pgsec;
591 	ns->options = 0;
592 
593 	if (ns->geom.pgsz == 256) {
594 		ns->options |= OPT_PAGE256;
595 	}
596 	else if (ns->geom.pgsz == 512) {
597 		ns->options |= (OPT_PAGE512 | OPT_AUTOINCR);
598 		if (ns->busw == 8)
599 			ns->options |= OPT_PAGE512_8BIT;
600 	} else if (ns->geom.pgsz == 2048) {
601 		ns->options |= OPT_PAGE2048;
602 	} else if (ns->geom.pgsz == 4096) {
603 		ns->options |= OPT_PAGE4096;
604 	} else {
605 		NS_ERR("init_nandsim: unknown page size %u\n", ns->geom.pgsz);
606 		return -EIO;
607 	}
608 
609 	if (ns->options & OPT_SMALLPAGE) {
610 		if (ns->geom.totsz <= (32 << 20)) {
611 			ns->geom.pgaddrbytes  = 3;
612 			ns->geom.secaddrbytes = 2;
613 		} else {
614 			ns->geom.pgaddrbytes  = 4;
615 			ns->geom.secaddrbytes = 3;
616 		}
617 	} else {
618 		if (ns->geom.totsz <= (128 << 20)) {
619 			ns->geom.pgaddrbytes  = 4;
620 			ns->geom.secaddrbytes = 2;
621 		} else {
622 			ns->geom.pgaddrbytes  = 5;
623 			ns->geom.secaddrbytes = 3;
624 		}
625 	}
626 
627 	/* Fill the partition_info structure */
628 	if (parts_num > ARRAY_SIZE(ns->partitions)) {
629 		NS_ERR("too many partitions.\n");
630 		ret = -EINVAL;
631 		goto error;
632 	}
633 	remains = ns->geom.totsz;
634 	next_offset = 0;
635 	for (i = 0; i < parts_num; ++i) {
636 		uint64_t part_sz = (uint64_t)parts[i] * ns->geom.secsz;
637 
638 		if (!part_sz || part_sz > remains) {
639 			NS_ERR("bad partition size.\n");
640 			ret = -EINVAL;
641 			goto error;
642 		}
643 		ns->partitions[i].name   = get_partition_name(i);
644 		ns->partitions[i].offset = next_offset;
645 		ns->partitions[i].size   = part_sz;
646 		next_offset += ns->partitions[i].size;
647 		remains -= ns->partitions[i].size;
648 	}
649 	ns->nbparts = parts_num;
650 	if (remains) {
651 		if (parts_num + 1 > ARRAY_SIZE(ns->partitions)) {
652 			NS_ERR("too many partitions.\n");
653 			ret = -EINVAL;
654 			goto error;
655 		}
656 		ns->partitions[i].name   = get_partition_name(i);
657 		ns->partitions[i].offset = next_offset;
658 		ns->partitions[i].size   = remains;
659 		ns->nbparts += 1;
660 	}
661 
662 	/* Detect how many ID bytes the NAND chip outputs */
663         for (i = 0; nand_flash_ids[i].name != NULL; i++) {
664                 if (second_id_byte != nand_flash_ids[i].id)
665                         continue;
666 		if (!(nand_flash_ids[i].options & NAND_NO_AUTOINCR))
667 			ns->options |= OPT_AUTOINCR;
668 	}
669 
670 	if (ns->busw == 16)
671 		NS_WARN("16-bit flashes support wasn't tested\n");
672 
673 	printk("flash size: %llu MiB\n",
674 			(unsigned long long)ns->geom.totsz >> 20);
675 	printk("page size: %u bytes\n",         ns->geom.pgsz);
676 	printk("OOB area size: %u bytes\n",     ns->geom.oobsz);
677 	printk("sector size: %u KiB\n",         ns->geom.secsz >> 10);
678 	printk("pages number: %u\n",            ns->geom.pgnum);
679 	printk("pages per sector: %u\n",        ns->geom.pgsec);
680 	printk("bus width: %u\n",               ns->busw);
681 	printk("bits in sector size: %u\n",     ns->geom.secshift);
682 	printk("bits in page size: %u\n",       ns->geom.pgshift);
683 	printk("bits in OOB size: %u\n",	ns->geom.oobshift);
684 	printk("flash size with OOB: %llu KiB\n",
685 			(unsigned long long)ns->geom.totszoob >> 10);
686 	printk("page address bytes: %u\n",      ns->geom.pgaddrbytes);
687 	printk("sector address bytes: %u\n",    ns->geom.secaddrbytes);
688 	printk("options: %#x\n",                ns->options);
689 
690 	if ((ret = alloc_device(ns)) != 0)
691 		goto error;
692 
693 	/* Allocate / initialize the internal buffer */
694 	ns->buf.byte = kmalloc(ns->geom.pgszoob, GFP_KERNEL);
695 	if (!ns->buf.byte) {
696 		NS_ERR("init_nandsim: unable to allocate %u bytes for the internal buffer\n",
697 			ns->geom.pgszoob);
698 		ret = -ENOMEM;
699 		goto error;
700 	}
701 	memset(ns->buf.byte, 0xFF, ns->geom.pgszoob);
702 
703 	return 0;
704 
705 error:
706 	free_device(ns);
707 
708 	return ret;
709 }
710 
711 /*
712  * Free the nandsim structure.
713  */
free_nandsim(struct nandsim * ns)714 static void free_nandsim(struct nandsim *ns)
715 {
716 	kfree(ns->buf.byte);
717 	free_device(ns);
718 
719 	return;
720 }
721 
parse_badblocks(struct nandsim * ns,struct mtd_info * mtd)722 static int parse_badblocks(struct nandsim *ns, struct mtd_info *mtd)
723 {
724 	char *w;
725 	int zero_ok;
726 	unsigned int erase_block_no;
727 	loff_t offset;
728 
729 	if (!badblocks)
730 		return 0;
731 	w = badblocks;
732 	do {
733 		zero_ok = (*w == '0' ? 1 : 0);
734 		erase_block_no = simple_strtoul(w, &w, 0);
735 		if (!zero_ok && !erase_block_no) {
736 			NS_ERR("invalid badblocks.\n");
737 			return -EINVAL;
738 		}
739 		offset = erase_block_no * ns->geom.secsz;
740 		if (mtd_block_markbad(mtd, offset)) {
741 			NS_ERR("invalid badblocks.\n");
742 			return -EINVAL;
743 		}
744 		if (*w == ',')
745 			w += 1;
746 	} while (*w);
747 	return 0;
748 }
749 
parse_weakblocks(void)750 static int parse_weakblocks(void)
751 {
752 	char *w;
753 	int zero_ok;
754 	unsigned int erase_block_no;
755 	unsigned int max_erases;
756 	struct weak_block *wb;
757 
758 	if (!weakblocks)
759 		return 0;
760 	w = weakblocks;
761 	do {
762 		zero_ok = (*w == '0' ? 1 : 0);
763 		erase_block_no = simple_strtoul(w, &w, 0);
764 		if (!zero_ok && !erase_block_no) {
765 			NS_ERR("invalid weakblocks.\n");
766 			return -EINVAL;
767 		}
768 		max_erases = 3;
769 		if (*w == ':') {
770 			w += 1;
771 			max_erases = simple_strtoul(w, &w, 0);
772 		}
773 		if (*w == ',')
774 			w += 1;
775 		wb = kzalloc(sizeof(*wb), GFP_KERNEL);
776 		if (!wb) {
777 			NS_ERR("unable to allocate memory.\n");
778 			return -ENOMEM;
779 		}
780 		wb->erase_block_no = erase_block_no;
781 		wb->max_erases = max_erases;
782 		list_add(&wb->list, &weak_blocks);
783 	} while (*w);
784 	return 0;
785 }
786 
erase_error(unsigned int erase_block_no)787 static int erase_error(unsigned int erase_block_no)
788 {
789 	struct weak_block *wb;
790 
791 	list_for_each_entry(wb, &weak_blocks, list)
792 		if (wb->erase_block_no == erase_block_no) {
793 			if (wb->erases_done >= wb->max_erases)
794 				return 1;
795 			wb->erases_done += 1;
796 			return 0;
797 		}
798 	return 0;
799 }
800 
parse_weakpages(void)801 static int parse_weakpages(void)
802 {
803 	char *w;
804 	int zero_ok;
805 	unsigned int page_no;
806 	unsigned int max_writes;
807 	struct weak_page *wp;
808 
809 	if (!weakpages)
810 		return 0;
811 	w = weakpages;
812 	do {
813 		zero_ok = (*w == '0' ? 1 : 0);
814 		page_no = simple_strtoul(w, &w, 0);
815 		if (!zero_ok && !page_no) {
816 			NS_ERR("invalid weakpagess.\n");
817 			return -EINVAL;
818 		}
819 		max_writes = 3;
820 		if (*w == ':') {
821 			w += 1;
822 			max_writes = simple_strtoul(w, &w, 0);
823 		}
824 		if (*w == ',')
825 			w += 1;
826 		wp = kzalloc(sizeof(*wp), GFP_KERNEL);
827 		if (!wp) {
828 			NS_ERR("unable to allocate memory.\n");
829 			return -ENOMEM;
830 		}
831 		wp->page_no = page_no;
832 		wp->max_writes = max_writes;
833 		list_add(&wp->list, &weak_pages);
834 	} while (*w);
835 	return 0;
836 }
837 
write_error(unsigned int page_no)838 static int write_error(unsigned int page_no)
839 {
840 	struct weak_page *wp;
841 
842 	list_for_each_entry(wp, &weak_pages, list)
843 		if (wp->page_no == page_no) {
844 			if (wp->writes_done >= wp->max_writes)
845 				return 1;
846 			wp->writes_done += 1;
847 			return 0;
848 		}
849 	return 0;
850 }
851 
parse_gravepages(void)852 static int parse_gravepages(void)
853 {
854 	char *g;
855 	int zero_ok;
856 	unsigned int page_no;
857 	unsigned int max_reads;
858 	struct grave_page *gp;
859 
860 	if (!gravepages)
861 		return 0;
862 	g = gravepages;
863 	do {
864 		zero_ok = (*g == '0' ? 1 : 0);
865 		page_no = simple_strtoul(g, &g, 0);
866 		if (!zero_ok && !page_no) {
867 			NS_ERR("invalid gravepagess.\n");
868 			return -EINVAL;
869 		}
870 		max_reads = 3;
871 		if (*g == ':') {
872 			g += 1;
873 			max_reads = simple_strtoul(g, &g, 0);
874 		}
875 		if (*g == ',')
876 			g += 1;
877 		gp = kzalloc(sizeof(*gp), GFP_KERNEL);
878 		if (!gp) {
879 			NS_ERR("unable to allocate memory.\n");
880 			return -ENOMEM;
881 		}
882 		gp->page_no = page_no;
883 		gp->max_reads = max_reads;
884 		list_add(&gp->list, &grave_pages);
885 	} while (*g);
886 	return 0;
887 }
888 
read_error(unsigned int page_no)889 static int read_error(unsigned int page_no)
890 {
891 	struct grave_page *gp;
892 
893 	list_for_each_entry(gp, &grave_pages, list)
894 		if (gp->page_no == page_no) {
895 			if (gp->reads_done >= gp->max_reads)
896 				return 1;
897 			gp->reads_done += 1;
898 			return 0;
899 		}
900 	return 0;
901 }
902 
free_lists(void)903 static void free_lists(void)
904 {
905 	struct list_head *pos, *n;
906 	list_for_each_safe(pos, n, &weak_blocks) {
907 		list_del(pos);
908 		kfree(list_entry(pos, struct weak_block, list));
909 	}
910 	list_for_each_safe(pos, n, &weak_pages) {
911 		list_del(pos);
912 		kfree(list_entry(pos, struct weak_page, list));
913 	}
914 	list_for_each_safe(pos, n, &grave_pages) {
915 		list_del(pos);
916 		kfree(list_entry(pos, struct grave_page, list));
917 	}
918 	kfree(erase_block_wear);
919 }
920 
setup_wear_reporting(struct mtd_info * mtd)921 static int setup_wear_reporting(struct mtd_info *mtd)
922 {
923 	size_t mem;
924 
925 	if (!rptwear)
926 		return 0;
927 	wear_eb_count = divide(mtd->size, mtd->erasesize);
928 	mem = wear_eb_count * sizeof(unsigned long);
929 	if (mem / sizeof(unsigned long) != wear_eb_count) {
930 		NS_ERR("Too many erase blocks for wear reporting\n");
931 		return -ENOMEM;
932 	}
933 	erase_block_wear = kzalloc(mem, GFP_KERNEL);
934 	if (!erase_block_wear) {
935 		NS_ERR("Too many erase blocks for wear reporting\n");
936 		return -ENOMEM;
937 	}
938 	return 0;
939 }
940 
update_wear(unsigned int erase_block_no)941 static void update_wear(unsigned int erase_block_no)
942 {
943 	unsigned long wmin = -1, wmax = 0, avg;
944 	unsigned long deciles[10], decile_max[10], tot = 0;
945 	unsigned int i;
946 
947 	if (!erase_block_wear)
948 		return;
949 	total_wear += 1;
950 	if (total_wear == 0)
951 		NS_ERR("Erase counter total overflow\n");
952 	erase_block_wear[erase_block_no] += 1;
953 	if (erase_block_wear[erase_block_no] == 0)
954 		NS_ERR("Erase counter overflow for erase block %u\n", erase_block_no);
955 	rptwear_cnt += 1;
956 	if (rptwear_cnt < rptwear)
957 		return;
958 	rptwear_cnt = 0;
959 	/* Calc wear stats */
960 	for (i = 0; i < wear_eb_count; ++i) {
961 		unsigned long wear = erase_block_wear[i];
962 		if (wear < wmin)
963 			wmin = wear;
964 		if (wear > wmax)
965 			wmax = wear;
966 		tot += wear;
967 	}
968 	for (i = 0; i < 9; ++i) {
969 		deciles[i] = 0;
970 		decile_max[i] = (wmax * (i + 1) + 5) / 10;
971 	}
972 	deciles[9] = 0;
973 	decile_max[9] = wmax;
974 	for (i = 0; i < wear_eb_count; ++i) {
975 		int d;
976 		unsigned long wear = erase_block_wear[i];
977 		for (d = 0; d < 10; ++d)
978 			if (wear <= decile_max[d]) {
979 				deciles[d] += 1;
980 				break;
981 			}
982 	}
983 	avg = tot / wear_eb_count;
984 	/* Output wear report */
985 	NS_INFO("*** Wear Report ***\n");
986 	NS_INFO("Total numbers of erases:  %lu\n", tot);
987 	NS_INFO("Number of erase blocks:   %u\n", wear_eb_count);
988 	NS_INFO("Average number of erases: %lu\n", avg);
989 	NS_INFO("Maximum number of erases: %lu\n", wmax);
990 	NS_INFO("Minimum number of erases: %lu\n", wmin);
991 	for (i = 0; i < 10; ++i) {
992 		unsigned long from = (i ? decile_max[i - 1] + 1 : 0);
993 		if (from > decile_max[i])
994 			continue;
995 		NS_INFO("Number of ebs with erase counts from %lu to %lu : %lu\n",
996 			from,
997 			decile_max[i],
998 			deciles[i]);
999 	}
1000 	NS_INFO("*** End of Wear Report ***\n");
1001 }
1002 
1003 /*
1004  * Returns the string representation of 'state' state.
1005  */
get_state_name(uint32_t state)1006 static char *get_state_name(uint32_t state)
1007 {
1008 	switch (NS_STATE(state)) {
1009 		case STATE_CMD_READ0:
1010 			return "STATE_CMD_READ0";
1011 		case STATE_CMD_READ1:
1012 			return "STATE_CMD_READ1";
1013 		case STATE_CMD_PAGEPROG:
1014 			return "STATE_CMD_PAGEPROG";
1015 		case STATE_CMD_READOOB:
1016 			return "STATE_CMD_READOOB";
1017 		case STATE_CMD_READSTART:
1018 			return "STATE_CMD_READSTART";
1019 		case STATE_CMD_ERASE1:
1020 			return "STATE_CMD_ERASE1";
1021 		case STATE_CMD_STATUS:
1022 			return "STATE_CMD_STATUS";
1023 		case STATE_CMD_STATUS_M:
1024 			return "STATE_CMD_STATUS_M";
1025 		case STATE_CMD_SEQIN:
1026 			return "STATE_CMD_SEQIN";
1027 		case STATE_CMD_READID:
1028 			return "STATE_CMD_READID";
1029 		case STATE_CMD_ERASE2:
1030 			return "STATE_CMD_ERASE2";
1031 		case STATE_CMD_RESET:
1032 			return "STATE_CMD_RESET";
1033 		case STATE_CMD_RNDOUT:
1034 			return "STATE_CMD_RNDOUT";
1035 		case STATE_CMD_RNDOUTSTART:
1036 			return "STATE_CMD_RNDOUTSTART";
1037 		case STATE_ADDR_PAGE:
1038 			return "STATE_ADDR_PAGE";
1039 		case STATE_ADDR_SEC:
1040 			return "STATE_ADDR_SEC";
1041 		case STATE_ADDR_ZERO:
1042 			return "STATE_ADDR_ZERO";
1043 		case STATE_ADDR_COLUMN:
1044 			return "STATE_ADDR_COLUMN";
1045 		case STATE_DATAIN:
1046 			return "STATE_DATAIN";
1047 		case STATE_DATAOUT:
1048 			return "STATE_DATAOUT";
1049 		case STATE_DATAOUT_ID:
1050 			return "STATE_DATAOUT_ID";
1051 		case STATE_DATAOUT_STATUS:
1052 			return "STATE_DATAOUT_STATUS";
1053 		case STATE_DATAOUT_STATUS_M:
1054 			return "STATE_DATAOUT_STATUS_M";
1055 		case STATE_READY:
1056 			return "STATE_READY";
1057 		case STATE_UNKNOWN:
1058 			return "STATE_UNKNOWN";
1059 	}
1060 
1061 	NS_ERR("get_state_name: unknown state, BUG\n");
1062 	return NULL;
1063 }
1064 
1065 /*
1066  * Check if command is valid.
1067  *
1068  * RETURNS: 1 if wrong command, 0 if right.
1069  */
check_command(int cmd)1070 static int check_command(int cmd)
1071 {
1072 	switch (cmd) {
1073 
1074 	case NAND_CMD_READ0:
1075 	case NAND_CMD_READ1:
1076 	case NAND_CMD_READSTART:
1077 	case NAND_CMD_PAGEPROG:
1078 	case NAND_CMD_READOOB:
1079 	case NAND_CMD_ERASE1:
1080 	case NAND_CMD_STATUS:
1081 	case NAND_CMD_SEQIN:
1082 	case NAND_CMD_READID:
1083 	case NAND_CMD_ERASE2:
1084 	case NAND_CMD_RESET:
1085 	case NAND_CMD_RNDOUT:
1086 	case NAND_CMD_RNDOUTSTART:
1087 		return 0;
1088 
1089 	case NAND_CMD_STATUS_MULTI:
1090 	default:
1091 		return 1;
1092 	}
1093 }
1094 
1095 /*
1096  * Returns state after command is accepted by command number.
1097  */
get_state_by_command(unsigned command)1098 static uint32_t get_state_by_command(unsigned command)
1099 {
1100 	switch (command) {
1101 		case NAND_CMD_READ0:
1102 			return STATE_CMD_READ0;
1103 		case NAND_CMD_READ1:
1104 			return STATE_CMD_READ1;
1105 		case NAND_CMD_PAGEPROG:
1106 			return STATE_CMD_PAGEPROG;
1107 		case NAND_CMD_READSTART:
1108 			return STATE_CMD_READSTART;
1109 		case NAND_CMD_READOOB:
1110 			return STATE_CMD_READOOB;
1111 		case NAND_CMD_ERASE1:
1112 			return STATE_CMD_ERASE1;
1113 		case NAND_CMD_STATUS:
1114 			return STATE_CMD_STATUS;
1115 		case NAND_CMD_STATUS_MULTI:
1116 			return STATE_CMD_STATUS_M;
1117 		case NAND_CMD_SEQIN:
1118 			return STATE_CMD_SEQIN;
1119 		case NAND_CMD_READID:
1120 			return STATE_CMD_READID;
1121 		case NAND_CMD_ERASE2:
1122 			return STATE_CMD_ERASE2;
1123 		case NAND_CMD_RESET:
1124 			return STATE_CMD_RESET;
1125 		case NAND_CMD_RNDOUT:
1126 			return STATE_CMD_RNDOUT;
1127 		case NAND_CMD_RNDOUTSTART:
1128 			return STATE_CMD_RNDOUTSTART;
1129 	}
1130 
1131 	NS_ERR("get_state_by_command: unknown command, BUG\n");
1132 	return 0;
1133 }
1134 
1135 /*
1136  * Move an address byte to the correspondent internal register.
1137  */
accept_addr_byte(struct nandsim * ns,u_char bt)1138 static inline void accept_addr_byte(struct nandsim *ns, u_char bt)
1139 {
1140 	uint byte = (uint)bt;
1141 
1142 	if (ns->regs.count < (ns->geom.pgaddrbytes - ns->geom.secaddrbytes))
1143 		ns->regs.column |= (byte << 8 * ns->regs.count);
1144 	else {
1145 		ns->regs.row |= (byte << 8 * (ns->regs.count -
1146 						ns->geom.pgaddrbytes +
1147 						ns->geom.secaddrbytes));
1148 	}
1149 
1150 	return;
1151 }
1152 
1153 /*
1154  * Switch to STATE_READY state.
1155  */
switch_to_ready_state(struct nandsim * ns,u_char status)1156 static inline void switch_to_ready_state(struct nandsim *ns, u_char status)
1157 {
1158 	NS_DBG("switch_to_ready_state: switch to %s state\n", get_state_name(STATE_READY));
1159 
1160 	ns->state       = STATE_READY;
1161 	ns->nxstate     = STATE_UNKNOWN;
1162 	ns->op          = NULL;
1163 	ns->npstates    = 0;
1164 	ns->stateidx    = 0;
1165 	ns->regs.num    = 0;
1166 	ns->regs.count  = 0;
1167 	ns->regs.off    = 0;
1168 	ns->regs.row    = 0;
1169 	ns->regs.column = 0;
1170 	ns->regs.status = status;
1171 }
1172 
1173 /*
1174  * If the operation isn't known yet, try to find it in the global array
1175  * of supported operations.
1176  *
1177  * Operation can be unknown because of the following.
1178  *   1. New command was accepted and this is the first call to find the
1179  *      correspondent states chain. In this case ns->npstates = 0;
1180  *   2. There are several operations which begin with the same command(s)
1181  *      (for example program from the second half and read from the
1182  *      second half operations both begin with the READ1 command). In this
1183  *      case the ns->pstates[] array contains previous states.
1184  *
1185  * Thus, the function tries to find operation containing the following
1186  * states (if the 'flag' parameter is 0):
1187  *    ns->pstates[0], ... ns->pstates[ns->npstates], ns->state
1188  *
1189  * If (one and only one) matching operation is found, it is accepted (
1190  * ns->ops, ns->state, ns->nxstate are initialized, ns->npstate is
1191  * zeroed).
1192  *
1193  * If there are several matches, the current state is pushed to the
1194  * ns->pstates.
1195  *
1196  * The operation can be unknown only while commands are input to the chip.
1197  * As soon as address command is accepted, the operation must be known.
1198  * In such situation the function is called with 'flag' != 0, and the
1199  * operation is searched using the following pattern:
1200  *     ns->pstates[0], ... ns->pstates[ns->npstates], <address input>
1201  *
1202  * It is supposed that this pattern must either match one operation or
1203  * none. There can't be ambiguity in that case.
1204  *
1205  * If no matches found, the function does the following:
1206  *   1. if there are saved states present, try to ignore them and search
1207  *      again only using the last command. If nothing was found, switch
1208  *      to the STATE_READY state.
1209  *   2. if there are no saved states, switch to the STATE_READY state.
1210  *
1211  * RETURNS: -2 - no matched operations found.
1212  *          -1 - several matches.
1213  *           0 - operation is found.
1214  */
find_operation(struct nandsim * ns,uint32_t flag)1215 static int find_operation(struct nandsim *ns, uint32_t flag)
1216 {
1217 	int opsfound = 0;
1218 	int i, j, idx = 0;
1219 
1220 	for (i = 0; i < NS_OPER_NUM; i++) {
1221 
1222 		int found = 1;
1223 
1224 		if (!(ns->options & ops[i].reqopts))
1225 			/* Ignore operations we can't perform */
1226 			continue;
1227 
1228 		if (flag) {
1229 			if (!(ops[i].states[ns->npstates] & STATE_ADDR_MASK))
1230 				continue;
1231 		} else {
1232 			if (NS_STATE(ns->state) != NS_STATE(ops[i].states[ns->npstates]))
1233 				continue;
1234 		}
1235 
1236 		for (j = 0; j < ns->npstates; j++)
1237 			if (NS_STATE(ops[i].states[j]) != NS_STATE(ns->pstates[j])
1238 				&& (ns->options & ops[idx].reqopts)) {
1239 				found = 0;
1240 				break;
1241 			}
1242 
1243 		if (found) {
1244 			idx = i;
1245 			opsfound += 1;
1246 		}
1247 	}
1248 
1249 	if (opsfound == 1) {
1250 		/* Exact match */
1251 		ns->op = &ops[idx].states[0];
1252 		if (flag) {
1253 			/*
1254 			 * In this case the find_operation function was
1255 			 * called when address has just began input. But it isn't
1256 			 * yet fully input and the current state must
1257 			 * not be one of STATE_ADDR_*, but the STATE_ADDR_*
1258 			 * state must be the next state (ns->nxstate).
1259 			 */
1260 			ns->stateidx = ns->npstates - 1;
1261 		} else {
1262 			ns->stateidx = ns->npstates;
1263 		}
1264 		ns->npstates = 0;
1265 		ns->state = ns->op[ns->stateidx];
1266 		ns->nxstate = ns->op[ns->stateidx + 1];
1267 		NS_DBG("find_operation: operation found, index: %d, state: %s, nxstate %s\n",
1268 				idx, get_state_name(ns->state), get_state_name(ns->nxstate));
1269 		return 0;
1270 	}
1271 
1272 	if (opsfound == 0) {
1273 		/* Nothing was found. Try to ignore previous commands (if any) and search again */
1274 		if (ns->npstates != 0) {
1275 			NS_DBG("find_operation: no operation found, try again with state %s\n",
1276 					get_state_name(ns->state));
1277 			ns->npstates = 0;
1278 			return find_operation(ns, 0);
1279 
1280 		}
1281 		NS_DBG("find_operation: no operations found\n");
1282 		switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
1283 		return -2;
1284 	}
1285 
1286 	if (flag) {
1287 		/* This shouldn't happen */
1288 		NS_DBG("find_operation: BUG, operation must be known if address is input\n");
1289 		return -2;
1290 	}
1291 
1292 	NS_DBG("find_operation: there is still ambiguity\n");
1293 
1294 	ns->pstates[ns->npstates++] = ns->state;
1295 
1296 	return -1;
1297 }
1298 
put_pages(struct nandsim * ns)1299 static void put_pages(struct nandsim *ns)
1300 {
1301 	int i;
1302 
1303 	for (i = 0; i < ns->held_cnt; i++)
1304 		page_cache_release(ns->held_pages[i]);
1305 }
1306 
1307 /* Get page cache pages in advance to provide NOFS memory allocation */
get_pages(struct nandsim * ns,struct file * file,size_t count,loff_t pos)1308 static int get_pages(struct nandsim *ns, struct file *file, size_t count, loff_t pos)
1309 {
1310 	pgoff_t index, start_index, end_index;
1311 	struct page *page;
1312 	struct address_space *mapping = file->f_mapping;
1313 
1314 	start_index = pos >> PAGE_CACHE_SHIFT;
1315 	end_index = (pos + count - 1) >> PAGE_CACHE_SHIFT;
1316 	if (end_index - start_index + 1 > NS_MAX_HELD_PAGES)
1317 		return -EINVAL;
1318 	ns->held_cnt = 0;
1319 	for (index = start_index; index <= end_index; index++) {
1320 		page = find_get_page(mapping, index);
1321 		if (page == NULL) {
1322 			page = find_or_create_page(mapping, index, GFP_NOFS);
1323 			if (page == NULL) {
1324 				write_inode_now(mapping->host, 1);
1325 				page = find_or_create_page(mapping, index, GFP_NOFS);
1326 			}
1327 			if (page == NULL) {
1328 				put_pages(ns);
1329 				return -ENOMEM;
1330 			}
1331 			unlock_page(page);
1332 		}
1333 		ns->held_pages[ns->held_cnt++] = page;
1334 	}
1335 	return 0;
1336 }
1337 
set_memalloc(void)1338 static int set_memalloc(void)
1339 {
1340 	if (current->flags & PF_MEMALLOC)
1341 		return 0;
1342 	current->flags |= PF_MEMALLOC;
1343 	return 1;
1344 }
1345 
clear_memalloc(int memalloc)1346 static void clear_memalloc(int memalloc)
1347 {
1348 	if (memalloc)
1349 		current->flags &= ~PF_MEMALLOC;
1350 }
1351 
read_file(struct nandsim * ns,struct file * file,void * buf,size_t count,loff_t * pos)1352 static ssize_t read_file(struct nandsim *ns, struct file *file, void *buf, size_t count, loff_t *pos)
1353 {
1354 	mm_segment_t old_fs;
1355 	ssize_t tx;
1356 	int err, memalloc;
1357 
1358 	err = get_pages(ns, file, count, *pos);
1359 	if (err)
1360 		return err;
1361 	old_fs = get_fs();
1362 	set_fs(get_ds());
1363 	memalloc = set_memalloc();
1364 	tx = vfs_read(file, (char __user *)buf, count, pos);
1365 	clear_memalloc(memalloc);
1366 	set_fs(old_fs);
1367 	put_pages(ns);
1368 	return tx;
1369 }
1370 
write_file(struct nandsim * ns,struct file * file,void * buf,size_t count,loff_t * pos)1371 static ssize_t write_file(struct nandsim *ns, struct file *file, void *buf, size_t count, loff_t *pos)
1372 {
1373 	mm_segment_t old_fs;
1374 	ssize_t tx;
1375 	int err, memalloc;
1376 
1377 	err = get_pages(ns, file, count, *pos);
1378 	if (err)
1379 		return err;
1380 	old_fs = get_fs();
1381 	set_fs(get_ds());
1382 	memalloc = set_memalloc();
1383 	tx = vfs_write(file, (char __user *)buf, count, pos);
1384 	clear_memalloc(memalloc);
1385 	set_fs(old_fs);
1386 	put_pages(ns);
1387 	return tx;
1388 }
1389 
1390 /*
1391  * Returns a pointer to the current page.
1392  */
NS_GET_PAGE(struct nandsim * ns)1393 static inline union ns_mem *NS_GET_PAGE(struct nandsim *ns)
1394 {
1395 	return &(ns->pages[ns->regs.row]);
1396 }
1397 
1398 /*
1399  * Retuns a pointer to the current byte, within the current page.
1400  */
NS_PAGE_BYTE_OFF(struct nandsim * ns)1401 static inline u_char *NS_PAGE_BYTE_OFF(struct nandsim *ns)
1402 {
1403 	return NS_GET_PAGE(ns)->byte + ns->regs.column + ns->regs.off;
1404 }
1405 
do_read_error(struct nandsim * ns,int num)1406 int do_read_error(struct nandsim *ns, int num)
1407 {
1408 	unsigned int page_no = ns->regs.row;
1409 
1410 	if (read_error(page_no)) {
1411 		int i;
1412 		memset(ns->buf.byte, 0xFF, num);
1413 		for (i = 0; i < num; ++i)
1414 			ns->buf.byte[i] = random32();
1415 		NS_WARN("simulating read error in page %u\n", page_no);
1416 		return 1;
1417 	}
1418 	return 0;
1419 }
1420 
do_bit_flips(struct nandsim * ns,int num)1421 void do_bit_flips(struct nandsim *ns, int num)
1422 {
1423 	if (bitflips && random32() < (1 << 22)) {
1424 		int flips = 1;
1425 		if (bitflips > 1)
1426 			flips = (random32() % (int) bitflips) + 1;
1427 		while (flips--) {
1428 			int pos = random32() % (num * 8);
1429 			ns->buf.byte[pos / 8] ^= (1 << (pos % 8));
1430 			NS_WARN("read_page: flipping bit %d in page %d "
1431 				"reading from %d ecc: corrected=%u failed=%u\n",
1432 				pos, ns->regs.row, ns->regs.column + ns->regs.off,
1433 				nsmtd->ecc_stats.corrected, nsmtd->ecc_stats.failed);
1434 		}
1435 	}
1436 }
1437 
1438 /*
1439  * Fill the NAND buffer with data read from the specified page.
1440  */
read_page(struct nandsim * ns,int num)1441 static void read_page(struct nandsim *ns, int num)
1442 {
1443 	union ns_mem *mypage;
1444 
1445 	if (ns->cfile) {
1446 		if (!ns->pages_written[ns->regs.row]) {
1447 			NS_DBG("read_page: page %d not written\n", ns->regs.row);
1448 			memset(ns->buf.byte, 0xFF, num);
1449 		} else {
1450 			loff_t pos;
1451 			ssize_t tx;
1452 
1453 			NS_DBG("read_page: page %d written, reading from %d\n",
1454 				ns->regs.row, ns->regs.column + ns->regs.off);
1455 			if (do_read_error(ns, num))
1456 				return;
1457 			pos = (loff_t)ns->regs.row * ns->geom.pgszoob + ns->regs.column + ns->regs.off;
1458 			tx = read_file(ns, ns->cfile, ns->buf.byte, num, &pos);
1459 			if (tx != num) {
1460 				NS_ERR("read_page: read error for page %d ret %ld\n", ns->regs.row, (long)tx);
1461 				return;
1462 			}
1463 			do_bit_flips(ns, num);
1464 		}
1465 		return;
1466 	}
1467 
1468 	mypage = NS_GET_PAGE(ns);
1469 	if (mypage->byte == NULL) {
1470 		NS_DBG("read_page: page %d not allocated\n", ns->regs.row);
1471 		memset(ns->buf.byte, 0xFF, num);
1472 	} else {
1473 		NS_DBG("read_page: page %d allocated, reading from %d\n",
1474 			ns->regs.row, ns->regs.column + ns->regs.off);
1475 		if (do_read_error(ns, num))
1476 			return;
1477 		memcpy(ns->buf.byte, NS_PAGE_BYTE_OFF(ns), num);
1478 		do_bit_flips(ns, num);
1479 	}
1480 }
1481 
1482 /*
1483  * Erase all pages in the specified sector.
1484  */
erase_sector(struct nandsim * ns)1485 static void erase_sector(struct nandsim *ns)
1486 {
1487 	union ns_mem *mypage;
1488 	int i;
1489 
1490 	if (ns->cfile) {
1491 		for (i = 0; i < ns->geom.pgsec; i++)
1492 			if (ns->pages_written[ns->regs.row + i]) {
1493 				NS_DBG("erase_sector: freeing page %d\n", ns->regs.row + i);
1494 				ns->pages_written[ns->regs.row + i] = 0;
1495 			}
1496 		return;
1497 	}
1498 
1499 	mypage = NS_GET_PAGE(ns);
1500 	for (i = 0; i < ns->geom.pgsec; i++) {
1501 		if (mypage->byte != NULL) {
1502 			NS_DBG("erase_sector: freeing page %d\n", ns->regs.row+i);
1503 			kmem_cache_free(ns->nand_pages_slab, mypage->byte);
1504 			mypage->byte = NULL;
1505 		}
1506 		mypage++;
1507 	}
1508 }
1509 
1510 /*
1511  * Program the specified page with the contents from the NAND buffer.
1512  */
prog_page(struct nandsim * ns,int num)1513 static int prog_page(struct nandsim *ns, int num)
1514 {
1515 	int i;
1516 	union ns_mem *mypage;
1517 	u_char *pg_off;
1518 
1519 	if (ns->cfile) {
1520 		loff_t off, pos;
1521 		ssize_t tx;
1522 		int all;
1523 
1524 		NS_DBG("prog_page: writing page %d\n", ns->regs.row);
1525 		pg_off = ns->file_buf + ns->regs.column + ns->regs.off;
1526 		off = (loff_t)ns->regs.row * ns->geom.pgszoob + ns->regs.column + ns->regs.off;
1527 		if (!ns->pages_written[ns->regs.row]) {
1528 			all = 1;
1529 			memset(ns->file_buf, 0xff, ns->geom.pgszoob);
1530 		} else {
1531 			all = 0;
1532 			pos = off;
1533 			tx = read_file(ns, ns->cfile, pg_off, num, &pos);
1534 			if (tx != num) {
1535 				NS_ERR("prog_page: read error for page %d ret %ld\n", ns->regs.row, (long)tx);
1536 				return -1;
1537 			}
1538 		}
1539 		for (i = 0; i < num; i++)
1540 			pg_off[i] &= ns->buf.byte[i];
1541 		if (all) {
1542 			pos = (loff_t)ns->regs.row * ns->geom.pgszoob;
1543 			tx = write_file(ns, ns->cfile, ns->file_buf, ns->geom.pgszoob, &pos);
1544 			if (tx != ns->geom.pgszoob) {
1545 				NS_ERR("prog_page: write error for page %d ret %ld\n", ns->regs.row, (long)tx);
1546 				return -1;
1547 			}
1548 			ns->pages_written[ns->regs.row] = 1;
1549 		} else {
1550 			pos = off;
1551 			tx = write_file(ns, ns->cfile, pg_off, num, &pos);
1552 			if (tx != num) {
1553 				NS_ERR("prog_page: write error for page %d ret %ld\n", ns->regs.row, (long)tx);
1554 				return -1;
1555 			}
1556 		}
1557 		return 0;
1558 	}
1559 
1560 	mypage = NS_GET_PAGE(ns);
1561 	if (mypage->byte == NULL) {
1562 		NS_DBG("prog_page: allocating page %d\n", ns->regs.row);
1563 		/*
1564 		 * We allocate memory with GFP_NOFS because a flash FS may
1565 		 * utilize this. If it is holding an FS lock, then gets here,
1566 		 * then kernel memory alloc runs writeback which goes to the FS
1567 		 * again and deadlocks. This was seen in practice.
1568 		 */
1569 		mypage->byte = kmem_cache_alloc(ns->nand_pages_slab, GFP_NOFS);
1570 		if (mypage->byte == NULL) {
1571 			NS_ERR("prog_page: error allocating memory for page %d\n", ns->regs.row);
1572 			return -1;
1573 		}
1574 		memset(mypage->byte, 0xFF, ns->geom.pgszoob);
1575 	}
1576 
1577 	pg_off = NS_PAGE_BYTE_OFF(ns);
1578 	for (i = 0; i < num; i++)
1579 		pg_off[i] &= ns->buf.byte[i];
1580 
1581 	return 0;
1582 }
1583 
1584 /*
1585  * If state has any action bit, perform this action.
1586  *
1587  * RETURNS: 0 if success, -1 if error.
1588  */
do_state_action(struct nandsim * ns,uint32_t action)1589 static int do_state_action(struct nandsim *ns, uint32_t action)
1590 {
1591 	int num;
1592 	int busdiv = ns->busw == 8 ? 1 : 2;
1593 	unsigned int erase_block_no, page_no;
1594 
1595 	action &= ACTION_MASK;
1596 
1597 	/* Check that page address input is correct */
1598 	if (action != ACTION_SECERASE && ns->regs.row >= ns->geom.pgnum) {
1599 		NS_WARN("do_state_action: wrong page number (%#x)\n", ns->regs.row);
1600 		return -1;
1601 	}
1602 
1603 	switch (action) {
1604 
1605 	case ACTION_CPY:
1606 		/*
1607 		 * Copy page data to the internal buffer.
1608 		 */
1609 
1610 		/* Column shouldn't be very large */
1611 		if (ns->regs.column >= (ns->geom.pgszoob - ns->regs.off)) {
1612 			NS_ERR("do_state_action: column number is too large\n");
1613 			break;
1614 		}
1615 		num = ns->geom.pgszoob - ns->regs.off - ns->regs.column;
1616 		read_page(ns, num);
1617 
1618 		NS_DBG("do_state_action: (ACTION_CPY:) copy %d bytes to int buf, raw offset %d\n",
1619 			num, NS_RAW_OFFSET(ns) + ns->regs.off);
1620 
1621 		if (ns->regs.off == 0)
1622 			NS_LOG("read page %d\n", ns->regs.row);
1623 		else if (ns->regs.off < ns->geom.pgsz)
1624 			NS_LOG("read page %d (second half)\n", ns->regs.row);
1625 		else
1626 			NS_LOG("read OOB of page %d\n", ns->regs.row);
1627 
1628 		NS_UDELAY(access_delay);
1629 		NS_UDELAY(input_cycle * ns->geom.pgsz / 1000 / busdiv);
1630 
1631 		break;
1632 
1633 	case ACTION_SECERASE:
1634 		/*
1635 		 * Erase sector.
1636 		 */
1637 
1638 		if (ns->lines.wp) {
1639 			NS_ERR("do_state_action: device is write-protected, ignore sector erase\n");
1640 			return -1;
1641 		}
1642 
1643 		if (ns->regs.row >= ns->geom.pgnum - ns->geom.pgsec
1644 			|| (ns->regs.row & ~(ns->geom.secsz - 1))) {
1645 			NS_ERR("do_state_action: wrong sector address (%#x)\n", ns->regs.row);
1646 			return -1;
1647 		}
1648 
1649 		ns->regs.row = (ns->regs.row <<
1650 				8 * (ns->geom.pgaddrbytes - ns->geom.secaddrbytes)) | ns->regs.column;
1651 		ns->regs.column = 0;
1652 
1653 		erase_block_no = ns->regs.row >> (ns->geom.secshift - ns->geom.pgshift);
1654 
1655 		NS_DBG("do_state_action: erase sector at address %#x, off = %d\n",
1656 				ns->regs.row, NS_RAW_OFFSET(ns));
1657 		NS_LOG("erase sector %u\n", erase_block_no);
1658 
1659 		erase_sector(ns);
1660 
1661 		NS_MDELAY(erase_delay);
1662 
1663 		if (erase_block_wear)
1664 			update_wear(erase_block_no);
1665 
1666 		if (erase_error(erase_block_no)) {
1667 			NS_WARN("simulating erase failure in erase block %u\n", erase_block_no);
1668 			return -1;
1669 		}
1670 
1671 		break;
1672 
1673 	case ACTION_PRGPAGE:
1674 		/*
1675 		 * Program page - move internal buffer data to the page.
1676 		 */
1677 
1678 		if (ns->lines.wp) {
1679 			NS_WARN("do_state_action: device is write-protected, programm\n");
1680 			return -1;
1681 		}
1682 
1683 		num = ns->geom.pgszoob - ns->regs.off - ns->regs.column;
1684 		if (num != ns->regs.count) {
1685 			NS_ERR("do_state_action: too few bytes were input (%d instead of %d)\n",
1686 					ns->regs.count, num);
1687 			return -1;
1688 		}
1689 
1690 		if (prog_page(ns, num) == -1)
1691 			return -1;
1692 
1693 		page_no = ns->regs.row;
1694 
1695 		NS_DBG("do_state_action: copy %d bytes from int buf to (%#x, %#x), raw off = %d\n",
1696 			num, ns->regs.row, ns->regs.column, NS_RAW_OFFSET(ns) + ns->regs.off);
1697 		NS_LOG("programm page %d\n", ns->regs.row);
1698 
1699 		NS_UDELAY(programm_delay);
1700 		NS_UDELAY(output_cycle * ns->geom.pgsz / 1000 / busdiv);
1701 
1702 		if (write_error(page_no)) {
1703 			NS_WARN("simulating write failure in page %u\n", page_no);
1704 			return -1;
1705 		}
1706 
1707 		break;
1708 
1709 	case ACTION_ZEROOFF:
1710 		NS_DBG("do_state_action: set internal offset to 0\n");
1711 		ns->regs.off = 0;
1712 		break;
1713 
1714 	case ACTION_HALFOFF:
1715 		if (!(ns->options & OPT_PAGE512_8BIT)) {
1716 			NS_ERR("do_state_action: BUG! can't skip half of page for non-512"
1717 				"byte page size 8x chips\n");
1718 			return -1;
1719 		}
1720 		NS_DBG("do_state_action: set internal offset to %d\n", ns->geom.pgsz/2);
1721 		ns->regs.off = ns->geom.pgsz/2;
1722 		break;
1723 
1724 	case ACTION_OOBOFF:
1725 		NS_DBG("do_state_action: set internal offset to %d\n", ns->geom.pgsz);
1726 		ns->regs.off = ns->geom.pgsz;
1727 		break;
1728 
1729 	default:
1730 		NS_DBG("do_state_action: BUG! unknown action\n");
1731 	}
1732 
1733 	return 0;
1734 }
1735 
1736 /*
1737  * Switch simulator's state.
1738  */
switch_state(struct nandsim * ns)1739 static void switch_state(struct nandsim *ns)
1740 {
1741 	if (ns->op) {
1742 		/*
1743 		 * The current operation have already been identified.
1744 		 * Just follow the states chain.
1745 		 */
1746 
1747 		ns->stateidx += 1;
1748 		ns->state = ns->nxstate;
1749 		ns->nxstate = ns->op[ns->stateidx + 1];
1750 
1751 		NS_DBG("switch_state: operation is known, switch to the next state, "
1752 			"state: %s, nxstate: %s\n",
1753 			get_state_name(ns->state), get_state_name(ns->nxstate));
1754 
1755 		/* See, whether we need to do some action */
1756 		if ((ns->state & ACTION_MASK) && do_state_action(ns, ns->state) < 0) {
1757 			switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
1758 			return;
1759 		}
1760 
1761 	} else {
1762 		/*
1763 		 * We don't yet know which operation we perform.
1764 		 * Try to identify it.
1765 		 */
1766 
1767 		/*
1768 		 *  The only event causing the switch_state function to
1769 		 *  be called with yet unknown operation is new command.
1770 		 */
1771 		ns->state = get_state_by_command(ns->regs.command);
1772 
1773 		NS_DBG("switch_state: operation is unknown, try to find it\n");
1774 
1775 		if (find_operation(ns, 0) != 0)
1776 			return;
1777 
1778 		if ((ns->state & ACTION_MASK) && do_state_action(ns, ns->state) < 0) {
1779 			switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
1780 			return;
1781 		}
1782 	}
1783 
1784 	/* For 16x devices column means the page offset in words */
1785 	if ((ns->nxstate & STATE_ADDR_MASK) && ns->busw == 16) {
1786 		NS_DBG("switch_state: double the column number for 16x device\n");
1787 		ns->regs.column <<= 1;
1788 	}
1789 
1790 	if (NS_STATE(ns->nxstate) == STATE_READY) {
1791 		/*
1792 		 * The current state is the last. Return to STATE_READY
1793 		 */
1794 
1795 		u_char status = NS_STATUS_OK(ns);
1796 
1797 		/* In case of data states, see if all bytes were input/output */
1798 		if ((ns->state & (STATE_DATAIN_MASK | STATE_DATAOUT_MASK))
1799 			&& ns->regs.count != ns->regs.num) {
1800 			NS_WARN("switch_state: not all bytes were processed, %d left\n",
1801 					ns->regs.num - ns->regs.count);
1802 			status = NS_STATUS_FAILED(ns);
1803 		}
1804 
1805 		NS_DBG("switch_state: operation complete, switch to STATE_READY state\n");
1806 
1807 		switch_to_ready_state(ns, status);
1808 
1809 		return;
1810 	} else if (ns->nxstate & (STATE_DATAIN_MASK | STATE_DATAOUT_MASK)) {
1811 		/*
1812 		 * If the next state is data input/output, switch to it now
1813 		 */
1814 
1815 		ns->state      = ns->nxstate;
1816 		ns->nxstate    = ns->op[++ns->stateidx + 1];
1817 		ns->regs.num   = ns->regs.count = 0;
1818 
1819 		NS_DBG("switch_state: the next state is data I/O, switch, "
1820 			"state: %s, nxstate: %s\n",
1821 			get_state_name(ns->state), get_state_name(ns->nxstate));
1822 
1823 		/*
1824 		 * Set the internal register to the count of bytes which
1825 		 * are expected to be input or output
1826 		 */
1827 		switch (NS_STATE(ns->state)) {
1828 			case STATE_DATAIN:
1829 			case STATE_DATAOUT:
1830 				ns->regs.num = ns->geom.pgszoob - ns->regs.off - ns->regs.column;
1831 				break;
1832 
1833 			case STATE_DATAOUT_ID:
1834 				ns->regs.num = ns->geom.idbytes;
1835 				break;
1836 
1837 			case STATE_DATAOUT_STATUS:
1838 			case STATE_DATAOUT_STATUS_M:
1839 				ns->regs.count = ns->regs.num = 0;
1840 				break;
1841 
1842 			default:
1843 				NS_ERR("switch_state: BUG! unknown data state\n");
1844 		}
1845 
1846 	} else if (ns->nxstate & STATE_ADDR_MASK) {
1847 		/*
1848 		 * If the next state is address input, set the internal
1849 		 * register to the number of expected address bytes
1850 		 */
1851 
1852 		ns->regs.count = 0;
1853 
1854 		switch (NS_STATE(ns->nxstate)) {
1855 			case STATE_ADDR_PAGE:
1856 				ns->regs.num = ns->geom.pgaddrbytes;
1857 
1858 				break;
1859 			case STATE_ADDR_SEC:
1860 				ns->regs.num = ns->geom.secaddrbytes;
1861 				break;
1862 
1863 			case STATE_ADDR_ZERO:
1864 				ns->regs.num = 1;
1865 				break;
1866 
1867 			case STATE_ADDR_COLUMN:
1868 				/* Column address is always 2 bytes */
1869 				ns->regs.num = ns->geom.pgaddrbytes - ns->geom.secaddrbytes;
1870 				break;
1871 
1872 			default:
1873 				NS_ERR("switch_state: BUG! unknown address state\n");
1874 		}
1875 	} else {
1876 		/*
1877 		 * Just reset internal counters.
1878 		 */
1879 
1880 		ns->regs.num = 0;
1881 		ns->regs.count = 0;
1882 	}
1883 }
1884 
ns_nand_read_byte(struct mtd_info * mtd)1885 static u_char ns_nand_read_byte(struct mtd_info *mtd)
1886 {
1887 	struct nandsim *ns = ((struct nand_chip *)mtd->priv)->priv;
1888 	u_char outb = 0x00;
1889 
1890 	/* Sanity and correctness checks */
1891 	if (!ns->lines.ce) {
1892 		NS_ERR("read_byte: chip is disabled, return %#x\n", (uint)outb);
1893 		return outb;
1894 	}
1895 	if (ns->lines.ale || ns->lines.cle) {
1896 		NS_ERR("read_byte: ALE or CLE pin is high, return %#x\n", (uint)outb);
1897 		return outb;
1898 	}
1899 	if (!(ns->state & STATE_DATAOUT_MASK)) {
1900 		NS_WARN("read_byte: unexpected data output cycle, state is %s "
1901 			"return %#x\n", get_state_name(ns->state), (uint)outb);
1902 		return outb;
1903 	}
1904 
1905 	/* Status register may be read as many times as it is wanted */
1906 	if (NS_STATE(ns->state) == STATE_DATAOUT_STATUS) {
1907 		NS_DBG("read_byte: return %#x status\n", ns->regs.status);
1908 		return ns->regs.status;
1909 	}
1910 
1911 	/* Check if there is any data in the internal buffer which may be read */
1912 	if (ns->regs.count == ns->regs.num) {
1913 		NS_WARN("read_byte: no more data to output, return %#x\n", (uint)outb);
1914 		return outb;
1915 	}
1916 
1917 	switch (NS_STATE(ns->state)) {
1918 		case STATE_DATAOUT:
1919 			if (ns->busw == 8) {
1920 				outb = ns->buf.byte[ns->regs.count];
1921 				ns->regs.count += 1;
1922 			} else {
1923 				outb = (u_char)cpu_to_le16(ns->buf.word[ns->regs.count >> 1]);
1924 				ns->regs.count += 2;
1925 			}
1926 			break;
1927 		case STATE_DATAOUT_ID:
1928 			NS_DBG("read_byte: read ID byte %d, total = %d\n", ns->regs.count, ns->regs.num);
1929 			outb = ns->ids[ns->regs.count];
1930 			ns->regs.count += 1;
1931 			break;
1932 		default:
1933 			BUG();
1934 	}
1935 
1936 	if (ns->regs.count == ns->regs.num) {
1937 		NS_DBG("read_byte: all bytes were read\n");
1938 
1939 		/*
1940 		 * The OPT_AUTOINCR allows to read next consecutive pages without
1941 		 * new read operation cycle.
1942 		 */
1943 		if ((ns->options & OPT_AUTOINCR) && NS_STATE(ns->state) == STATE_DATAOUT) {
1944 			ns->regs.count = 0;
1945 			if (ns->regs.row + 1 < ns->geom.pgnum)
1946 				ns->regs.row += 1;
1947 			NS_DBG("read_byte: switch to the next page (%#x)\n", ns->regs.row);
1948 			do_state_action(ns, ACTION_CPY);
1949 		}
1950 		else if (NS_STATE(ns->nxstate) == STATE_READY)
1951 			switch_state(ns);
1952 
1953 	}
1954 
1955 	return outb;
1956 }
1957 
ns_nand_write_byte(struct mtd_info * mtd,u_char byte)1958 static void ns_nand_write_byte(struct mtd_info *mtd, u_char byte)
1959 {
1960 	struct nandsim *ns = ((struct nand_chip *)mtd->priv)->priv;
1961 
1962 	/* Sanity and correctness checks */
1963 	if (!ns->lines.ce) {
1964 		NS_ERR("write_byte: chip is disabled, ignore write\n");
1965 		return;
1966 	}
1967 	if (ns->lines.ale && ns->lines.cle) {
1968 		NS_ERR("write_byte: ALE and CLE pins are high simultaneously, ignore write\n");
1969 		return;
1970 	}
1971 
1972 	if (ns->lines.cle == 1) {
1973 		/*
1974 		 * The byte written is a command.
1975 		 */
1976 
1977 		if (byte == NAND_CMD_RESET) {
1978 			NS_LOG("reset chip\n");
1979 			switch_to_ready_state(ns, NS_STATUS_OK(ns));
1980 			return;
1981 		}
1982 
1983 		/* Check that the command byte is correct */
1984 		if (check_command(byte)) {
1985 			NS_ERR("write_byte: unknown command %#x\n", (uint)byte);
1986 			return;
1987 		}
1988 
1989 		if (NS_STATE(ns->state) == STATE_DATAOUT_STATUS
1990 			|| NS_STATE(ns->state) == STATE_DATAOUT_STATUS_M
1991 			|| NS_STATE(ns->state) == STATE_DATAOUT) {
1992 			int row = ns->regs.row;
1993 
1994 			switch_state(ns);
1995 			if (byte == NAND_CMD_RNDOUT)
1996 				ns->regs.row = row;
1997 		}
1998 
1999 		/* Check if chip is expecting command */
2000 		if (NS_STATE(ns->nxstate) != STATE_UNKNOWN && !(ns->nxstate & STATE_CMD_MASK)) {
2001 			/* Do not warn if only 2 id bytes are read */
2002 			if (!(ns->regs.command == NAND_CMD_READID &&
2003 			    NS_STATE(ns->state) == STATE_DATAOUT_ID && ns->regs.count == 2)) {
2004 				/*
2005 				 * We are in situation when something else (not command)
2006 				 * was expected but command was input. In this case ignore
2007 				 * previous command(s)/state(s) and accept the last one.
2008 				 */
2009 				NS_WARN("write_byte: command (%#x) wasn't expected, expected state is %s, "
2010 					"ignore previous states\n", (uint)byte, get_state_name(ns->nxstate));
2011 			}
2012 			switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2013 		}
2014 
2015 		NS_DBG("command byte corresponding to %s state accepted\n",
2016 			get_state_name(get_state_by_command(byte)));
2017 		ns->regs.command = byte;
2018 		switch_state(ns);
2019 
2020 	} else if (ns->lines.ale == 1) {
2021 		/*
2022 		 * The byte written is an address.
2023 		 */
2024 
2025 		if (NS_STATE(ns->nxstate) == STATE_UNKNOWN) {
2026 
2027 			NS_DBG("write_byte: operation isn't known yet, identify it\n");
2028 
2029 			if (find_operation(ns, 1) < 0)
2030 				return;
2031 
2032 			if ((ns->state & ACTION_MASK) && do_state_action(ns, ns->state) < 0) {
2033 				switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2034 				return;
2035 			}
2036 
2037 			ns->regs.count = 0;
2038 			switch (NS_STATE(ns->nxstate)) {
2039 				case STATE_ADDR_PAGE:
2040 					ns->regs.num = ns->geom.pgaddrbytes;
2041 					break;
2042 				case STATE_ADDR_SEC:
2043 					ns->regs.num = ns->geom.secaddrbytes;
2044 					break;
2045 				case STATE_ADDR_ZERO:
2046 					ns->regs.num = 1;
2047 					break;
2048 				default:
2049 					BUG();
2050 			}
2051 		}
2052 
2053 		/* Check that chip is expecting address */
2054 		if (!(ns->nxstate & STATE_ADDR_MASK)) {
2055 			NS_ERR("write_byte: address (%#x) isn't expected, expected state is %s, "
2056 				"switch to STATE_READY\n", (uint)byte, get_state_name(ns->nxstate));
2057 			switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2058 			return;
2059 		}
2060 
2061 		/* Check if this is expected byte */
2062 		if (ns->regs.count == ns->regs.num) {
2063 			NS_ERR("write_byte: no more address bytes expected\n");
2064 			switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2065 			return;
2066 		}
2067 
2068 		accept_addr_byte(ns, byte);
2069 
2070 		ns->regs.count += 1;
2071 
2072 		NS_DBG("write_byte: address byte %#x was accepted (%d bytes input, %d expected)\n",
2073 				(uint)byte, ns->regs.count, ns->regs.num);
2074 
2075 		if (ns->regs.count == ns->regs.num) {
2076 			NS_DBG("address (%#x, %#x) is accepted\n", ns->regs.row, ns->regs.column);
2077 			switch_state(ns);
2078 		}
2079 
2080 	} else {
2081 		/*
2082 		 * The byte written is an input data.
2083 		 */
2084 
2085 		/* Check that chip is expecting data input */
2086 		if (!(ns->state & STATE_DATAIN_MASK)) {
2087 			NS_ERR("write_byte: data input (%#x) isn't expected, state is %s, "
2088 				"switch to %s\n", (uint)byte,
2089 				get_state_name(ns->state), get_state_name(STATE_READY));
2090 			switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2091 			return;
2092 		}
2093 
2094 		/* Check if this is expected byte */
2095 		if (ns->regs.count == ns->regs.num) {
2096 			NS_WARN("write_byte: %u input bytes has already been accepted, ignore write\n",
2097 					ns->regs.num);
2098 			return;
2099 		}
2100 
2101 		if (ns->busw == 8) {
2102 			ns->buf.byte[ns->regs.count] = byte;
2103 			ns->regs.count += 1;
2104 		} else {
2105 			ns->buf.word[ns->regs.count >> 1] = cpu_to_le16((uint16_t)byte);
2106 			ns->regs.count += 2;
2107 		}
2108 	}
2109 
2110 	return;
2111 }
2112 
ns_hwcontrol(struct mtd_info * mtd,int cmd,unsigned int bitmask)2113 static void ns_hwcontrol(struct mtd_info *mtd, int cmd, unsigned int bitmask)
2114 {
2115 	struct nandsim *ns = ((struct nand_chip *)mtd->priv)->priv;
2116 
2117 	ns->lines.cle = bitmask & NAND_CLE ? 1 : 0;
2118 	ns->lines.ale = bitmask & NAND_ALE ? 1 : 0;
2119 	ns->lines.ce = bitmask & NAND_NCE ? 1 : 0;
2120 
2121 	if (cmd != NAND_CMD_NONE)
2122 		ns_nand_write_byte(mtd, cmd);
2123 }
2124 
ns_device_ready(struct mtd_info * mtd)2125 static int ns_device_ready(struct mtd_info *mtd)
2126 {
2127 	NS_DBG("device_ready\n");
2128 	return 1;
2129 }
2130 
ns_nand_read_word(struct mtd_info * mtd)2131 static uint16_t ns_nand_read_word(struct mtd_info *mtd)
2132 {
2133 	struct nand_chip *chip = (struct nand_chip *)mtd->priv;
2134 
2135 	NS_DBG("read_word\n");
2136 
2137 	return chip->read_byte(mtd) | (chip->read_byte(mtd) << 8);
2138 }
2139 
ns_nand_write_buf(struct mtd_info * mtd,const u_char * buf,int len)2140 static void ns_nand_write_buf(struct mtd_info *mtd, const u_char *buf, int len)
2141 {
2142 	struct nandsim *ns = ((struct nand_chip *)mtd->priv)->priv;
2143 
2144 	/* Check that chip is expecting data input */
2145 	if (!(ns->state & STATE_DATAIN_MASK)) {
2146 		NS_ERR("write_buf: data input isn't expected, state is %s, "
2147 			"switch to STATE_READY\n", get_state_name(ns->state));
2148 		switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2149 		return;
2150 	}
2151 
2152 	/* Check if these are expected bytes */
2153 	if (ns->regs.count + len > ns->regs.num) {
2154 		NS_ERR("write_buf: too many input bytes\n");
2155 		switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2156 		return;
2157 	}
2158 
2159 	memcpy(ns->buf.byte + ns->regs.count, buf, len);
2160 	ns->regs.count += len;
2161 
2162 	if (ns->regs.count == ns->regs.num) {
2163 		NS_DBG("write_buf: %d bytes were written\n", ns->regs.count);
2164 	}
2165 }
2166 
ns_nand_read_buf(struct mtd_info * mtd,u_char * buf,int len)2167 static void ns_nand_read_buf(struct mtd_info *mtd, u_char *buf, int len)
2168 {
2169 	struct nandsim *ns = ((struct nand_chip *)mtd->priv)->priv;
2170 
2171 	/* Sanity and correctness checks */
2172 	if (!ns->lines.ce) {
2173 		NS_ERR("read_buf: chip is disabled\n");
2174 		return;
2175 	}
2176 	if (ns->lines.ale || ns->lines.cle) {
2177 		NS_ERR("read_buf: ALE or CLE pin is high\n");
2178 		return;
2179 	}
2180 	if (!(ns->state & STATE_DATAOUT_MASK)) {
2181 		NS_WARN("read_buf: unexpected data output cycle, current state is %s\n",
2182 			get_state_name(ns->state));
2183 		return;
2184 	}
2185 
2186 	if (NS_STATE(ns->state) != STATE_DATAOUT) {
2187 		int i;
2188 
2189 		for (i = 0; i < len; i++)
2190 			buf[i] = ((struct nand_chip *)mtd->priv)->read_byte(mtd);
2191 
2192 		return;
2193 	}
2194 
2195 	/* Check if these are expected bytes */
2196 	if (ns->regs.count + len > ns->regs.num) {
2197 		NS_ERR("read_buf: too many bytes to read\n");
2198 		switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2199 		return;
2200 	}
2201 
2202 	memcpy(buf, ns->buf.byte + ns->regs.count, len);
2203 	ns->regs.count += len;
2204 
2205 	if (ns->regs.count == ns->regs.num) {
2206 		if ((ns->options & OPT_AUTOINCR) && NS_STATE(ns->state) == STATE_DATAOUT) {
2207 			ns->regs.count = 0;
2208 			if (ns->regs.row + 1 < ns->geom.pgnum)
2209 				ns->regs.row += 1;
2210 			NS_DBG("read_buf: switch to the next page (%#x)\n", ns->regs.row);
2211 			do_state_action(ns, ACTION_CPY);
2212 		}
2213 		else if (NS_STATE(ns->nxstate) == STATE_READY)
2214 			switch_state(ns);
2215 	}
2216 
2217 	return;
2218 }
2219 
ns_nand_verify_buf(struct mtd_info * mtd,const u_char * buf,int len)2220 static int ns_nand_verify_buf(struct mtd_info *mtd, const u_char *buf, int len)
2221 {
2222 	ns_nand_read_buf(mtd, (u_char *)&ns_verify_buf[0], len);
2223 
2224 	if (!memcmp(buf, &ns_verify_buf[0], len)) {
2225 		NS_DBG("verify_buf: the buffer is OK\n");
2226 		return 0;
2227 	} else {
2228 		NS_DBG("verify_buf: the buffer is wrong\n");
2229 		return -EFAULT;
2230 	}
2231 }
2232 
2233 /*
2234  * Module initialization function
2235  */
ns_init_module(void)2236 static int __init ns_init_module(void)
2237 {
2238 	struct nand_chip *chip;
2239 	struct nandsim *nand;
2240 	int retval = -ENOMEM, i;
2241 
2242 	if (bus_width != 8 && bus_width != 16) {
2243 		NS_ERR("wrong bus width (%d), use only 8 or 16\n", bus_width);
2244 		return -EINVAL;
2245 	}
2246 
2247 	/* Allocate and initialize mtd_info, nand_chip and nandsim structures */
2248 	nsmtd = kzalloc(sizeof(struct mtd_info) + sizeof(struct nand_chip)
2249 				+ sizeof(struct nandsim), GFP_KERNEL);
2250 	if (!nsmtd) {
2251 		NS_ERR("unable to allocate core structures.\n");
2252 		return -ENOMEM;
2253 	}
2254 	chip        = (struct nand_chip *)(nsmtd + 1);
2255         nsmtd->priv = (void *)chip;
2256 	nand        = (struct nandsim *)(chip + 1);
2257 	chip->priv  = (void *)nand;
2258 
2259 	/*
2260 	 * Register simulator's callbacks.
2261 	 */
2262 	chip->cmd_ctrl	 = ns_hwcontrol;
2263 	chip->read_byte  = ns_nand_read_byte;
2264 	chip->dev_ready  = ns_device_ready;
2265 	chip->write_buf  = ns_nand_write_buf;
2266 	chip->read_buf   = ns_nand_read_buf;
2267 	chip->verify_buf = ns_nand_verify_buf;
2268 	chip->read_word  = ns_nand_read_word;
2269 	chip->ecc.mode   = NAND_ECC_SOFT;
2270 	/* The NAND_SKIP_BBTSCAN option is necessary for 'overridesize' */
2271 	/* and 'badblocks' parameters to work */
2272 	chip->options   |= NAND_SKIP_BBTSCAN;
2273 
2274 	switch (bbt) {
2275 	case 2:
2276 		 chip->bbt_options |= NAND_BBT_NO_OOB;
2277 	case 1:
2278 		 chip->bbt_options |= NAND_BBT_USE_FLASH;
2279 	case 0:
2280 		break;
2281 	default:
2282 		NS_ERR("bbt has to be 0..2\n");
2283 		retval = -EINVAL;
2284 		goto error;
2285 	}
2286 	/*
2287 	 * Perform minimum nandsim structure initialization to handle
2288 	 * the initial ID read command correctly
2289 	 */
2290 	if (third_id_byte != 0xFF || fourth_id_byte != 0xFF)
2291 		nand->geom.idbytes = 4;
2292 	else
2293 		nand->geom.idbytes = 2;
2294 	nand->regs.status = NS_STATUS_OK(nand);
2295 	nand->nxstate = STATE_UNKNOWN;
2296 	nand->options |= OPT_PAGE256; /* temporary value */
2297 	nand->ids[0] = first_id_byte;
2298 	nand->ids[1] = second_id_byte;
2299 	nand->ids[2] = third_id_byte;
2300 	nand->ids[3] = fourth_id_byte;
2301 	if (bus_width == 16) {
2302 		nand->busw = 16;
2303 		chip->options |= NAND_BUSWIDTH_16;
2304 	}
2305 
2306 	nsmtd->owner = THIS_MODULE;
2307 
2308 	if ((retval = parse_weakblocks()) != 0)
2309 		goto error;
2310 
2311 	if ((retval = parse_weakpages()) != 0)
2312 		goto error;
2313 
2314 	if ((retval = parse_gravepages()) != 0)
2315 		goto error;
2316 
2317 	retval = nand_scan_ident(nsmtd, 1, NULL);
2318 	if (retval) {
2319 		NS_ERR("cannot scan NAND Simulator device\n");
2320 		if (retval > 0)
2321 			retval = -ENXIO;
2322 		goto error;
2323 	}
2324 
2325 	if (bch) {
2326 		unsigned int eccsteps, eccbytes;
2327 		if (!mtd_nand_has_bch()) {
2328 			NS_ERR("BCH ECC support is disabled\n");
2329 			retval = -EINVAL;
2330 			goto error;
2331 		}
2332 		/* use 512-byte ecc blocks */
2333 		eccsteps = nsmtd->writesize/512;
2334 		eccbytes = (bch*13+7)/8;
2335 		/* do not bother supporting small page devices */
2336 		if ((nsmtd->oobsize < 64) || !eccsteps) {
2337 			NS_ERR("bch not available on small page devices\n");
2338 			retval = -EINVAL;
2339 			goto error;
2340 		}
2341 		if ((eccbytes*eccsteps+2) > nsmtd->oobsize) {
2342 			NS_ERR("invalid bch value %u\n", bch);
2343 			retval = -EINVAL;
2344 			goto error;
2345 		}
2346 		chip->ecc.mode = NAND_ECC_SOFT_BCH;
2347 		chip->ecc.size = 512;
2348 		chip->ecc.bytes = eccbytes;
2349 		NS_INFO("using %u-bit/%u bytes BCH ECC\n", bch, chip->ecc.size);
2350 	}
2351 
2352 	retval = nand_scan_tail(nsmtd);
2353 	if (retval) {
2354 		NS_ERR("can't register NAND Simulator\n");
2355 		if (retval > 0)
2356 			retval = -ENXIO;
2357 		goto error;
2358 	}
2359 
2360 	if (overridesize) {
2361 		uint64_t new_size = (uint64_t)nsmtd->erasesize << overridesize;
2362 		if (new_size >> overridesize != nsmtd->erasesize) {
2363 			NS_ERR("overridesize is too big\n");
2364 			goto err_exit;
2365 		}
2366 		/* N.B. This relies on nand_scan not doing anything with the size before we change it */
2367 		nsmtd->size = new_size;
2368 		chip->chipsize = new_size;
2369 		chip->chip_shift = ffs(nsmtd->erasesize) + overridesize - 1;
2370 		chip->pagemask = (chip->chipsize >> chip->page_shift) - 1;
2371 	}
2372 
2373 	if ((retval = setup_wear_reporting(nsmtd)) != 0)
2374 		goto err_exit;
2375 
2376 	if ((retval = init_nandsim(nsmtd)) != 0)
2377 		goto err_exit;
2378 
2379 	if ((retval = nand_default_bbt(nsmtd)) != 0)
2380 		goto err_exit;
2381 
2382 	if ((retval = parse_badblocks(nand, nsmtd)) != 0)
2383 		goto err_exit;
2384 
2385 	/* Register NAND partitions */
2386 	retval = mtd_device_register(nsmtd, &nand->partitions[0],
2387 				     nand->nbparts);
2388 	if (retval != 0)
2389 		goto err_exit;
2390 
2391         return 0;
2392 
2393 err_exit:
2394 	free_nandsim(nand);
2395 	nand_release(nsmtd);
2396 	for (i = 0;i < ARRAY_SIZE(nand->partitions); ++i)
2397 		kfree(nand->partitions[i].name);
2398 error:
2399 	kfree(nsmtd);
2400 	free_lists();
2401 
2402 	return retval;
2403 }
2404 
2405 module_init(ns_init_module);
2406 
2407 /*
2408  * Module clean-up function
2409  */
ns_cleanup_module(void)2410 static void __exit ns_cleanup_module(void)
2411 {
2412 	struct nandsim *ns = ((struct nand_chip *)nsmtd->priv)->priv;
2413 	int i;
2414 
2415 	free_nandsim(ns);    /* Free nandsim private resources */
2416 	nand_release(nsmtd); /* Unregister driver */
2417 	for (i = 0;i < ARRAY_SIZE(ns->partitions); ++i)
2418 		kfree(ns->partitions[i].name);
2419 	kfree(nsmtd);        /* Free other structures */
2420 	free_lists();
2421 }
2422 
2423 module_exit(ns_cleanup_module);
2424 
2425 MODULE_LICENSE ("GPL");
2426 MODULE_AUTHOR ("Artem B. Bityuckiy");
2427 MODULE_DESCRIPTION ("The NAND flash simulator");
2428