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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * NAND flash simulator.4 *5 * Author: Artem B. Bityuckiy <dedekind@oktetlabs.ru>, <dedekind@infradead.org>6 *7 * Copyright (C) 2004 Nokia Corporation8 *9 * Note: NS means "NAND Simulator".10 * Note: Input means input TO flash chip, output means output FROM chip.11 */12 13#define pr_fmt(fmt)  "[nandsim]" fmt14 15#include <linux/init.h>16#include <linux/types.h>17#include <linux/module.h>18#include <linux/moduleparam.h>19#include <linux/vmalloc.h>20#include <linux/math64.h>21#include <linux/slab.h>22#include <linux/errno.h>23#include <linux/string.h>24#include <linux/mtd/mtd.h>25#include <linux/mtd/rawnand.h>26#include <linux/mtd/partitions.h>27#include <linux/delay.h>28#include <linux/list.h>29#include <linux/random.h>30#include <linux/sched.h>31#include <linux/sched/mm.h>32#include <linux/fs.h>33#include <linux/pagemap.h>34#include <linux/seq_file.h>35#include <linux/debugfs.h>36 37/* Default simulator parameters values */38#if !defined(CONFIG_NANDSIM_FIRST_ID_BYTE)  || \39    !defined(CONFIG_NANDSIM_SECOND_ID_BYTE) || \40    !defined(CONFIG_NANDSIM_THIRD_ID_BYTE)  || \41    !defined(CONFIG_NANDSIM_FOURTH_ID_BYTE)42#define CONFIG_NANDSIM_FIRST_ID_BYTE  0x9843#define CONFIG_NANDSIM_SECOND_ID_BYTE 0x3944#define CONFIG_NANDSIM_THIRD_ID_BYTE  0xFF /* No byte */45#define CONFIG_NANDSIM_FOURTH_ID_BYTE 0xFF /* No byte */46#endif47 48#ifndef CONFIG_NANDSIM_ACCESS_DELAY49#define CONFIG_NANDSIM_ACCESS_DELAY 2550#endif51#ifndef CONFIG_NANDSIM_PROGRAMM_DELAY52#define CONFIG_NANDSIM_PROGRAMM_DELAY 20053#endif54#ifndef CONFIG_NANDSIM_ERASE_DELAY55#define CONFIG_NANDSIM_ERASE_DELAY 256#endif57#ifndef CONFIG_NANDSIM_OUTPUT_CYCLE58#define CONFIG_NANDSIM_OUTPUT_CYCLE 4059#endif60#ifndef CONFIG_NANDSIM_INPUT_CYCLE61#define CONFIG_NANDSIM_INPUT_CYCLE  5062#endif63#ifndef CONFIG_NANDSIM_BUS_WIDTH64#define CONFIG_NANDSIM_BUS_WIDTH  865#endif66#ifndef CONFIG_NANDSIM_DO_DELAYS67#define CONFIG_NANDSIM_DO_DELAYS  068#endif69#ifndef CONFIG_NANDSIM_LOG70#define CONFIG_NANDSIM_LOG        071#endif72#ifndef CONFIG_NANDSIM_DBG73#define CONFIG_NANDSIM_DBG        074#endif75#ifndef CONFIG_NANDSIM_MAX_PARTS76#define CONFIG_NANDSIM_MAX_PARTS  3277#endif78 79static uint access_delay   = CONFIG_NANDSIM_ACCESS_DELAY;80static uint programm_delay = CONFIG_NANDSIM_PROGRAMM_DELAY;81static uint erase_delay    = CONFIG_NANDSIM_ERASE_DELAY;82static uint output_cycle   = CONFIG_NANDSIM_OUTPUT_CYCLE;83static uint input_cycle    = CONFIG_NANDSIM_INPUT_CYCLE;84static uint bus_width      = CONFIG_NANDSIM_BUS_WIDTH;85static uint do_delays      = CONFIG_NANDSIM_DO_DELAYS;86static uint log            = CONFIG_NANDSIM_LOG;87static uint dbg            = CONFIG_NANDSIM_DBG;88static unsigned long parts[CONFIG_NANDSIM_MAX_PARTS];89static unsigned int parts_num;90static char *badblocks = NULL;91static char *weakblocks = NULL;92static char *weakpages = NULL;93static unsigned int bitflips = 0;94static char *gravepages = NULL;95static unsigned int overridesize = 0;96static char *cache_file = NULL;97static unsigned int bbt;98static unsigned int bch;99static u_char id_bytes[8] = {100	[0] = CONFIG_NANDSIM_FIRST_ID_BYTE,101	[1] = CONFIG_NANDSIM_SECOND_ID_BYTE,102	[2] = CONFIG_NANDSIM_THIRD_ID_BYTE,103	[3] = CONFIG_NANDSIM_FOURTH_ID_BYTE,104	[4 ... 7] = 0xFF,105};106 107module_param_array(id_bytes, byte, NULL, 0400);108module_param_named(first_id_byte, id_bytes[0], byte, 0400);109module_param_named(second_id_byte, id_bytes[1], byte, 0400);110module_param_named(third_id_byte, id_bytes[2], byte, 0400);111module_param_named(fourth_id_byte, id_bytes[3], byte, 0400);112module_param(access_delay,   uint, 0400);113module_param(programm_delay, uint, 0400);114module_param(erase_delay,    uint, 0400);115module_param(output_cycle,   uint, 0400);116module_param(input_cycle,    uint, 0400);117module_param(bus_width,      uint, 0400);118module_param(do_delays,      uint, 0400);119module_param(log,            uint, 0400);120module_param(dbg,            uint, 0400);121module_param_array(parts, ulong, &parts_num, 0400);122module_param(badblocks,      charp, 0400);123module_param(weakblocks,     charp, 0400);124module_param(weakpages,      charp, 0400);125module_param(bitflips,       uint, 0400);126module_param(gravepages,     charp, 0400);127module_param(overridesize,   uint, 0400);128module_param(cache_file,     charp, 0400);129module_param(bbt,	     uint, 0400);130module_param(bch,	     uint, 0400);131 132MODULE_PARM_DESC(id_bytes,       "The ID bytes returned by NAND Flash 'read ID' command");133MODULE_PARM_DESC(first_id_byte,  "The first byte returned by NAND Flash 'read ID' command (manufacturer ID) (obsolete)");134MODULE_PARM_DESC(second_id_byte, "The second byte returned by NAND Flash 'read ID' command (chip ID) (obsolete)");135MODULE_PARM_DESC(third_id_byte,  "The third byte returned by NAND Flash 'read ID' command (obsolete)");136MODULE_PARM_DESC(fourth_id_byte, "The fourth byte returned by NAND Flash 'read ID' command (obsolete)");137MODULE_PARM_DESC(access_delay,   "Initial page access delay (microseconds)");138MODULE_PARM_DESC(programm_delay, "Page programm delay (microseconds");139MODULE_PARM_DESC(erase_delay,    "Sector erase delay (milliseconds)");140MODULE_PARM_DESC(output_cycle,   "Word output (from flash) time (nanoseconds)");141MODULE_PARM_DESC(input_cycle,    "Word input (to flash) time (nanoseconds)");142MODULE_PARM_DESC(bus_width,      "Chip's bus width (8- or 16-bit)");143MODULE_PARM_DESC(do_delays,      "Simulate NAND delays using busy-waits if not zero");144MODULE_PARM_DESC(log,            "Perform logging if not zero");145MODULE_PARM_DESC(dbg,            "Output debug information if not zero");146MODULE_PARM_DESC(parts,          "Partition sizes (in erase blocks) separated by commas");147/* Page and erase block positions for the following parameters are independent of any partitions */148MODULE_PARM_DESC(badblocks,      "Erase blocks that are initially marked bad, separated by commas");149MODULE_PARM_DESC(weakblocks,     "Weak erase blocks [: remaining erase cycles (defaults to 3)]"150				 " separated by commas e.g. 113:2 means eb 113"151				 " can be erased only twice before failing");152MODULE_PARM_DESC(weakpages,      "Weak pages [: maximum writes (defaults to 3)]"153				 " separated by commas e.g. 1401:2 means page 1401"154				 " can be written only twice before failing");155MODULE_PARM_DESC(bitflips,       "Maximum number of random bit flips per page (zero by default)");156MODULE_PARM_DESC(gravepages,     "Pages that lose data [: maximum reads (defaults to 3)]"157				 " separated by commas e.g. 1401:2 means page 1401"158				 " can be read only twice before failing");159MODULE_PARM_DESC(overridesize,   "Specifies the NAND Flash size overriding the ID bytes. "160				 "The size is specified in erase blocks and as the exponent of a power of two"161				 " e.g. 5 means a size of 32 erase blocks");162MODULE_PARM_DESC(cache_file,     "File to use to cache nand pages instead of memory");163MODULE_PARM_DESC(bbt,		 "0 OOB, 1 BBT with marker in OOB, 2 BBT with marker in data area");164MODULE_PARM_DESC(bch,		 "Enable BCH ecc and set how many bits should "165				 "be correctable in 512-byte blocks");166 167/* The largest possible page size */168#define NS_LARGEST_PAGE_SIZE	4096169 170/* Simulator's output macros (logging, debugging, warning, error) */171#define NS_LOG(args...) \172	do { if (log) pr_debug(" log: " args); } while(0)173#define NS_DBG(args...) \174	do { if (dbg) pr_debug(" debug: " args); } while(0)175#define NS_WARN(args...) \176	do { pr_warn(" warning: " args); } while(0)177#define NS_ERR(args...) \178	do { pr_err(" error: " args); } while(0)179#define NS_INFO(args...) \180	do { pr_info(" " args); } while(0)181 182/* Busy-wait delay macros (microseconds, milliseconds) */183#define NS_UDELAY(us) \184        do { if (do_delays) udelay(us); } while(0)185#define NS_MDELAY(us) \186        do { if (do_delays) mdelay(us); } while(0)187 188/* Is the nandsim structure initialized ? */189#define NS_IS_INITIALIZED(ns) ((ns)->geom.totsz != 0)190 191/* Good operation completion status */192#define NS_STATUS_OK(ns) (NAND_STATUS_READY | (NAND_STATUS_WP * ((ns)->lines.wp == 0)))193 194/* Operation failed completion status */195#define NS_STATUS_FAILED(ns) (NAND_STATUS_FAIL | NS_STATUS_OK(ns))196 197/* Calculate the page offset in flash RAM image by (row, column) address */198#define NS_RAW_OFFSET(ns) \199	(((ns)->regs.row * (ns)->geom.pgszoob) + (ns)->regs.column)200 201/* Calculate the OOB offset in flash RAM image by (row, column) address */202#define NS_RAW_OFFSET_OOB(ns) (NS_RAW_OFFSET(ns) + ns->geom.pgsz)203 204/* Calculate the byte shift in the next page to access */205#define NS_PAGE_BYTE_SHIFT(ns) ((ns)->regs.column + (ns)->regs.off)206 207/* After a command is input, the simulator goes to one of the following states */208#define STATE_CMD_READ0        0x00000001 /* read data from the beginning of page */209#define STATE_CMD_READ1        0x00000002 /* read data from the second half of page */210#define STATE_CMD_READSTART    0x00000003 /* read data second command (large page devices) */211#define STATE_CMD_PAGEPROG     0x00000004 /* start page program */212#define STATE_CMD_READOOB      0x00000005 /* read OOB area */213#define STATE_CMD_ERASE1       0x00000006 /* sector erase first command */214#define STATE_CMD_STATUS       0x00000007 /* read status */215#define STATE_CMD_SEQIN        0x00000009 /* sequential data input */216#define STATE_CMD_READID       0x0000000A /* read ID */217#define STATE_CMD_ERASE2       0x0000000B /* sector erase second command */218#define STATE_CMD_RESET        0x0000000C /* reset */219#define STATE_CMD_RNDOUT       0x0000000D /* random output command */220#define STATE_CMD_RNDOUTSTART  0x0000000E /* random output start command */221#define STATE_CMD_MASK         0x0000000F /* command states mask */222 223/* After an address is input, the simulator goes to one of these states */224#define STATE_ADDR_PAGE        0x00000010 /* full (row, column) address is accepted */225#define STATE_ADDR_SEC         0x00000020 /* sector address was accepted */226#define STATE_ADDR_COLUMN      0x00000030 /* column address was accepted */227#define STATE_ADDR_ZERO        0x00000040 /* one byte zero address was accepted */228#define STATE_ADDR_MASK        0x00000070 /* address states mask */229 230/* During data input/output the simulator is in these states */231#define STATE_DATAIN           0x00000100 /* waiting for data input */232#define STATE_DATAIN_MASK      0x00000100 /* data input states mask */233 234#define STATE_DATAOUT          0x00001000 /* waiting for page data output */235#define STATE_DATAOUT_ID       0x00002000 /* waiting for ID bytes output */236#define STATE_DATAOUT_STATUS   0x00003000 /* waiting for status output */237#define STATE_DATAOUT_MASK     0x00007000 /* data output states mask */238 239/* Previous operation is done, ready to accept new requests */240#define STATE_READY            0x00000000241 242/* This state is used to mark that the next state isn't known yet */243#define STATE_UNKNOWN          0x10000000244 245/* Simulator's actions bit masks */246#define ACTION_CPY       0x00100000 /* copy page/OOB to the internal buffer */247#define ACTION_PRGPAGE   0x00200000 /* program the internal buffer to flash */248#define ACTION_SECERASE  0x00300000 /* erase sector */249#define ACTION_ZEROOFF   0x00400000 /* don't add any offset to address */250#define ACTION_HALFOFF   0x00500000 /* add to address half of page */251#define ACTION_OOBOFF    0x00600000 /* add to address OOB offset */252#define ACTION_MASK      0x00700000 /* action mask */253 254#define NS_OPER_NUM      13 /* Number of operations supported by the simulator */255#define NS_OPER_STATES   6  /* Maximum number of states in operation */256 257#define OPT_ANY          0xFFFFFFFF /* any chip supports this operation */258#define OPT_PAGE512      0x00000002 /* 512-byte  page chips */259#define OPT_PAGE2048     0x00000008 /* 2048-byte page chips */260#define OPT_PAGE512_8BIT 0x00000040 /* 512-byte page chips with 8-bit bus width */261#define OPT_PAGE4096     0x00000080 /* 4096-byte page chips */262#define OPT_LARGEPAGE    (OPT_PAGE2048 | OPT_PAGE4096) /* 2048 & 4096-byte page chips */263#define OPT_SMALLPAGE    (OPT_PAGE512) /* 512-byte page chips */264 265/* Remove action bits from state */266#define NS_STATE(x) ((x) & ~ACTION_MASK)267 268/*269 * Maximum previous states which need to be saved. Currently saving is270 * only needed for page program operation with preceded read command271 * (which is only valid for 512-byte pages).272 */273#define NS_MAX_PREVSTATES 1274 275/* Maximum page cache pages needed to read or write a NAND page to the cache_file */276#define NS_MAX_HELD_PAGES 16277 278/*279 * A union to represent flash memory contents and flash buffer.280 */281union ns_mem {282	u_char *byte;    /* for byte access */283	uint16_t *word;  /* for 16-bit word access */284};285 286/*287 * The structure which describes all the internal simulator data.288 */289struct nandsim {290	struct nand_chip chip;291	struct nand_controller base;292	struct mtd_partition partitions[CONFIG_NANDSIM_MAX_PARTS];293	unsigned int nbparts;294 295	uint busw;              /* flash chip bus width (8 or 16) */296	u_char ids[8];          /* chip's ID bytes */297	uint32_t options;       /* chip's characteristic bits */298	uint32_t state;         /* current chip state */299	uint32_t nxstate;       /* next expected state */300 301	uint32_t *op;           /* current operation, NULL operations isn't known yet  */302	uint32_t pstates[NS_MAX_PREVSTATES]; /* previous states */303	uint16_t npstates;      /* number of previous states saved */304	uint16_t stateidx;      /* current state index */305 306	/* The simulated NAND flash pages array */307	union ns_mem *pages;308 309	/* Slab allocator for nand pages */310	struct kmem_cache *nand_pages_slab;311 312	/* Internal buffer of page + OOB size bytes */313	union ns_mem buf;314 315	/* NAND flash "geometry" */316	struct {317		uint64_t totsz;     /* total flash size, bytes */318		uint32_t secsz;     /* flash sector (erase block) size, bytes */319		uint pgsz;          /* NAND flash page size, bytes */320		uint oobsz;         /* page OOB area size, bytes */321		uint64_t totszoob;  /* total flash size including OOB, bytes */322		uint pgszoob;       /* page size including OOB , bytes*/323		uint secszoob;      /* sector size including OOB, bytes */324		uint pgnum;         /* total number of pages */325		uint pgsec;         /* number of pages per sector */326		uint secshift;      /* bits number in sector size */327		uint pgshift;       /* bits number in page size */328		uint pgaddrbytes;   /* bytes per page address */329		uint secaddrbytes;  /* bytes per sector address */330		uint idbytes;       /* the number ID bytes that this chip outputs */331	} geom;332 333	/* NAND flash internal registers */334	struct {335		unsigned command; /* the command register */336		u_char   status;  /* the status register */337		uint     row;     /* the page number */338		uint     column;  /* the offset within page */339		uint     count;   /* internal counter */340		uint     num;     /* number of bytes which must be processed */341		uint     off;     /* fixed page offset */342	} regs;343 344	/* NAND flash lines state */345        struct {346                int ce;  /* chip Enable */347                int cle; /* command Latch Enable */348                int ale; /* address Latch Enable */349                int wp;  /* write Protect */350        } lines;351 352	/* Fields needed when using a cache file */353	struct file *cfile; /* Open file */354	unsigned long *pages_written; /* Which pages have been written */355	void *file_buf;356	struct page *held_pages[NS_MAX_HELD_PAGES];357	int held_cnt;358 359	/* debugfs entry */360	struct dentry *dent;361};362 363/*364 * Operations array. To perform any operation the simulator must pass365 * through the correspondent states chain.366 */367static struct nandsim_operations {368	uint32_t reqopts;  /* options which are required to perform the operation */369	uint32_t states[NS_OPER_STATES]; /* operation's states */370} ops[NS_OPER_NUM] = {371	/* Read page + OOB from the beginning */372	{OPT_SMALLPAGE, {STATE_CMD_READ0 | ACTION_ZEROOFF, STATE_ADDR_PAGE | ACTION_CPY,373			STATE_DATAOUT, STATE_READY}},374	/* Read page + OOB from the second half */375	{OPT_PAGE512_8BIT, {STATE_CMD_READ1 | ACTION_HALFOFF, STATE_ADDR_PAGE | ACTION_CPY,376			STATE_DATAOUT, STATE_READY}},377	/* Read OOB */378	{OPT_SMALLPAGE, {STATE_CMD_READOOB | ACTION_OOBOFF, STATE_ADDR_PAGE | ACTION_CPY,379			STATE_DATAOUT, STATE_READY}},380	/* Program page starting from the beginning */381	{OPT_ANY, {STATE_CMD_SEQIN, STATE_ADDR_PAGE, STATE_DATAIN,382			STATE_CMD_PAGEPROG | ACTION_PRGPAGE, STATE_READY}},383	/* Program page starting from the beginning */384	{OPT_SMALLPAGE, {STATE_CMD_READ0, STATE_CMD_SEQIN | ACTION_ZEROOFF, STATE_ADDR_PAGE,385			      STATE_DATAIN, STATE_CMD_PAGEPROG | ACTION_PRGPAGE, STATE_READY}},386	/* Program page starting from the second half */387	{OPT_PAGE512, {STATE_CMD_READ1, STATE_CMD_SEQIN | ACTION_HALFOFF, STATE_ADDR_PAGE,388			      STATE_DATAIN, STATE_CMD_PAGEPROG | ACTION_PRGPAGE, STATE_READY}},389	/* Program OOB */390	{OPT_SMALLPAGE, {STATE_CMD_READOOB, STATE_CMD_SEQIN | ACTION_OOBOFF, STATE_ADDR_PAGE,391			      STATE_DATAIN, STATE_CMD_PAGEPROG | ACTION_PRGPAGE, STATE_READY}},392	/* Erase sector */393	{OPT_ANY, {STATE_CMD_ERASE1, STATE_ADDR_SEC, STATE_CMD_ERASE2 | ACTION_SECERASE, STATE_READY}},394	/* Read status */395	{OPT_ANY, {STATE_CMD_STATUS, STATE_DATAOUT_STATUS, STATE_READY}},396	/* Read ID */397	{OPT_ANY, {STATE_CMD_READID, STATE_ADDR_ZERO, STATE_DATAOUT_ID, STATE_READY}},398	/* Large page devices read page */399	{OPT_LARGEPAGE, {STATE_CMD_READ0, STATE_ADDR_PAGE, STATE_CMD_READSTART | ACTION_CPY,400			       STATE_DATAOUT, STATE_READY}},401	/* Large page devices random page read */402	{OPT_LARGEPAGE, {STATE_CMD_RNDOUT, STATE_ADDR_COLUMN, STATE_CMD_RNDOUTSTART | ACTION_CPY,403			       STATE_DATAOUT, STATE_READY}},404};405 406struct weak_block {407	struct list_head list;408	unsigned int erase_block_no;409	unsigned int max_erases;410	unsigned int erases_done;411};412 413static LIST_HEAD(weak_blocks);414 415struct weak_page {416	struct list_head list;417	unsigned int page_no;418	unsigned int max_writes;419	unsigned int writes_done;420};421 422static LIST_HEAD(weak_pages);423 424struct grave_page {425	struct list_head list;426	unsigned int page_no;427	unsigned int max_reads;428	unsigned int reads_done;429};430 431static LIST_HEAD(grave_pages);432 433static unsigned long *erase_block_wear = NULL;434static unsigned int wear_eb_count = 0;435static unsigned long total_wear = 0;436 437/* MTD structure for NAND controller */438static struct mtd_info *nsmtd;439 440static int ns_show(struct seq_file *m, void *private)441{442	unsigned long wmin = -1, wmax = 0, avg;443	unsigned long deciles[10], decile_max[10], tot = 0;444	unsigned int i;445 446	/* Calc wear stats */447	for (i = 0; i < wear_eb_count; ++i) {448		unsigned long wear = erase_block_wear[i];449		if (wear < wmin)450			wmin = wear;451		if (wear > wmax)452			wmax = wear;453		tot += wear;454	}455 456	for (i = 0; i < 9; ++i) {457		deciles[i] = 0;458		decile_max[i] = (wmax * (i + 1) + 5) / 10;459	}460	deciles[9] = 0;461	decile_max[9] = wmax;462	for (i = 0; i < wear_eb_count; ++i) {463		int d;464		unsigned long wear = erase_block_wear[i];465		for (d = 0; d < 10; ++d)466			if (wear <= decile_max[d]) {467				deciles[d] += 1;468				break;469			}470	}471	avg = tot / wear_eb_count;472 473	/* Output wear report */474	seq_printf(m, "Total numbers of erases:  %lu\n", tot);475	seq_printf(m, "Number of erase blocks:   %u\n", wear_eb_count);476	seq_printf(m, "Average number of erases: %lu\n", avg);477	seq_printf(m, "Maximum number of erases: %lu\n", wmax);478	seq_printf(m, "Minimum number of erases: %lu\n", wmin);479	for (i = 0; i < 10; ++i) {480		unsigned long from = (i ? decile_max[i - 1] + 1 : 0);481		if (from > decile_max[i])482			continue;483		seq_printf(m, "Number of ebs with erase counts from %lu to %lu : %lu\n",484			from,485			decile_max[i],486			deciles[i]);487	}488 489	return 0;490}491DEFINE_SHOW_ATTRIBUTE(ns);492 493/**494 * ns_debugfs_create - initialize debugfs495 * @ns: nandsim device description object496 *497 * This function creates all debugfs files for UBI device @ubi. Returns zero in498 * case of success and a negative error code in case of failure.499 */500static int ns_debugfs_create(struct nandsim *ns)501{502	struct dentry *root = nsmtd->dbg.dfs_dir;503 504	/*505	 * Just skip debugfs initialization when the debugfs directory is506	 * missing.507	 */508	if (IS_ERR_OR_NULL(root)) {509		if (IS_ENABLED(CONFIG_DEBUG_FS) &&510		    !IS_ENABLED(CONFIG_MTD_PARTITIONED_MASTER))511			NS_WARN("CONFIG_MTD_PARTITIONED_MASTER must be enabled to expose debugfs stuff\n");512		return 0;513	}514 515	ns->dent = debugfs_create_file("nandsim_wear_report", 0400, root, ns,516				       &ns_fops);517	if (IS_ERR_OR_NULL(ns->dent)) {518		NS_ERR("cannot create \"nandsim_wear_report\" debugfs entry\n");519		return -1;520	}521 522	return 0;523}524 525static void ns_debugfs_remove(struct nandsim *ns)526{527	debugfs_remove_recursive(ns->dent);528}529 530/*531 * Allocate array of page pointers, create slab allocation for an array532 * and initialize the array by NULL pointers.533 *534 * RETURNS: 0 if success, -ENOMEM if memory alloc fails.535 */536static int __init ns_alloc_device(struct nandsim *ns)537{538	struct file *cfile;539	int i, err;540 541	if (cache_file) {542		cfile = filp_open(cache_file, O_CREAT | O_RDWR | O_LARGEFILE, 0600);543		if (IS_ERR(cfile))544			return PTR_ERR(cfile);545		if (!(cfile->f_mode & FMODE_CAN_READ)) {546			NS_ERR("alloc_device: cache file not readable\n");547			err = -EINVAL;548			goto err_close_filp;549		}550		if (!(cfile->f_mode & FMODE_CAN_WRITE)) {551			NS_ERR("alloc_device: cache file not writeable\n");552			err = -EINVAL;553			goto err_close_filp;554		}555		ns->pages_written =556			vzalloc(array_size(sizeof(unsigned long),557					   BITS_TO_LONGS(ns->geom.pgnum)));558		if (!ns->pages_written) {559			NS_ERR("alloc_device: unable to allocate pages written array\n");560			err = -ENOMEM;561			goto err_close_filp;562		}563		ns->file_buf = kmalloc(ns->geom.pgszoob, GFP_KERNEL);564		if (!ns->file_buf) {565			NS_ERR("alloc_device: unable to allocate file buf\n");566			err = -ENOMEM;567			goto err_free_pw;568		}569		ns->cfile = cfile;570 571		return 0;572 573err_free_pw:574		vfree(ns->pages_written);575err_close_filp:576		filp_close(cfile, NULL);577 578		return err;579	}580 581	ns->pages = vmalloc(array_size(sizeof(union ns_mem), ns->geom.pgnum));582	if (!ns->pages) {583		NS_ERR("alloc_device: unable to allocate page array\n");584		return -ENOMEM;585	}586	for (i = 0; i < ns->geom.pgnum; i++) {587		ns->pages[i].byte = NULL;588	}589	ns->nand_pages_slab = kmem_cache_create("nandsim",590						ns->geom.pgszoob, 0, 0, NULL);591	if (!ns->nand_pages_slab) {592		NS_ERR("cache_create: unable to create kmem_cache\n");593		err = -ENOMEM;594		goto err_free_pg;595	}596 597	return 0;598 599err_free_pg:600	vfree(ns->pages);601 602	return err;603}604 605/*606 * Free any allocated pages, and free the array of page pointers.607 */608static void ns_free_device(struct nandsim *ns)609{610	int i;611 612	if (ns->cfile) {613		kfree(ns->file_buf);614		vfree(ns->pages_written);615		filp_close(ns->cfile, NULL);616		return;617	}618 619	if (ns->pages) {620		for (i = 0; i < ns->geom.pgnum; i++) {621			if (ns->pages[i].byte)622				kmem_cache_free(ns->nand_pages_slab,623						ns->pages[i].byte);624		}625		kmem_cache_destroy(ns->nand_pages_slab);626		vfree(ns->pages);627	}628}629 630static char __init *ns_get_partition_name(int i)631{632	return kasprintf(GFP_KERNEL, "NAND simulator partition %d", i);633}634 635/*636 * Initialize the nandsim structure.637 *638 * RETURNS: 0 if success, -ERRNO if failure.639 */640static int __init ns_init(struct mtd_info *mtd)641{642	struct nand_chip *chip = mtd_to_nand(mtd);643	struct nandsim   *ns   = nand_get_controller_data(chip);644	int i, ret = 0;645	uint64_t remains;646	uint64_t next_offset;647 648	if (NS_IS_INITIALIZED(ns)) {649		NS_ERR("init_nandsim: nandsim is already initialized\n");650		return -EIO;651	}652 653	/* Initialize the NAND flash parameters */654	ns->busw = chip->options & NAND_BUSWIDTH_16 ? 16 : 8;655	ns->geom.totsz    = mtd->size;656	ns->geom.pgsz     = mtd->writesize;657	ns->geom.oobsz    = mtd->oobsize;658	ns->geom.secsz    = mtd->erasesize;659	ns->geom.pgszoob  = ns->geom.pgsz + ns->geom.oobsz;660	ns->geom.pgnum    = div_u64(ns->geom.totsz, ns->geom.pgsz);661	ns->geom.totszoob = ns->geom.totsz + (uint64_t)ns->geom.pgnum * ns->geom.oobsz;662	ns->geom.secshift = ffs(ns->geom.secsz) - 1;663	ns->geom.pgshift  = chip->page_shift;664	ns->geom.pgsec    = ns->geom.secsz / ns->geom.pgsz;665	ns->geom.secszoob = ns->geom.secsz + ns->geom.oobsz * ns->geom.pgsec;666	ns->options = 0;667 668	if (ns->geom.pgsz == 512) {669		ns->options |= OPT_PAGE512;670		if (ns->busw == 8)671			ns->options |= OPT_PAGE512_8BIT;672	} else if (ns->geom.pgsz == 2048) {673		ns->options |= OPT_PAGE2048;674	} else if (ns->geom.pgsz == 4096) {675		ns->options |= OPT_PAGE4096;676	} else {677		NS_ERR("init_nandsim: unknown page size %u\n", ns->geom.pgsz);678		return -EIO;679	}680 681	if (ns->options & OPT_SMALLPAGE) {682		if (ns->geom.totsz <= (32 << 20)) {683			ns->geom.pgaddrbytes  = 3;684			ns->geom.secaddrbytes = 2;685		} else {686			ns->geom.pgaddrbytes  = 4;687			ns->geom.secaddrbytes = 3;688		}689	} else {690		if (ns->geom.totsz <= (128 << 20)) {691			ns->geom.pgaddrbytes  = 4;692			ns->geom.secaddrbytes = 2;693		} else {694			ns->geom.pgaddrbytes  = 5;695			ns->geom.secaddrbytes = 3;696		}697	}698 699	/* Fill the partition_info structure */700	if (parts_num > ARRAY_SIZE(ns->partitions)) {701		NS_ERR("too many partitions.\n");702		return -EINVAL;703	}704	remains = ns->geom.totsz;705	next_offset = 0;706	for (i = 0; i < parts_num; ++i) {707		uint64_t part_sz = (uint64_t)parts[i] * ns->geom.secsz;708 709		if (!part_sz || part_sz > remains) {710			NS_ERR("bad partition size.\n");711			return -EINVAL;712		}713		ns->partitions[i].name = ns_get_partition_name(i);714		if (!ns->partitions[i].name) {715			NS_ERR("unable to allocate memory.\n");716			return -ENOMEM;717		}718		ns->partitions[i].offset = next_offset;719		ns->partitions[i].size   = part_sz;720		next_offset += ns->partitions[i].size;721		remains -= ns->partitions[i].size;722	}723	ns->nbparts = parts_num;724	if (remains) {725		if (parts_num + 1 > ARRAY_SIZE(ns->partitions)) {726			NS_ERR("too many partitions.\n");727			ret = -EINVAL;728			goto free_partition_names;729		}730		ns->partitions[i].name = ns_get_partition_name(i);731		if (!ns->partitions[i].name) {732			NS_ERR("unable to allocate memory.\n");733			ret = -ENOMEM;734			goto free_partition_names;735		}736		ns->partitions[i].offset = next_offset;737		ns->partitions[i].size   = remains;738		ns->nbparts += 1;739	}740 741	if (ns->busw == 16)742		NS_WARN("16-bit flashes support wasn't tested\n");743 744	printk("flash size: %llu MiB\n",745			(unsigned long long)ns->geom.totsz >> 20);746	printk("page size: %u bytes\n",         ns->geom.pgsz);747	printk("OOB area size: %u bytes\n",     ns->geom.oobsz);748	printk("sector size: %u KiB\n",         ns->geom.secsz >> 10);749	printk("pages number: %u\n",            ns->geom.pgnum);750	printk("pages per sector: %u\n",        ns->geom.pgsec);751	printk("bus width: %u\n",               ns->busw);752	printk("bits in sector size: %u\n",     ns->geom.secshift);753	printk("bits in page size: %u\n",       ns->geom.pgshift);754	printk("bits in OOB size: %u\n",	ffs(ns->geom.oobsz) - 1);755	printk("flash size with OOB: %llu KiB\n",756			(unsigned long long)ns->geom.totszoob >> 10);757	printk("page address bytes: %u\n",      ns->geom.pgaddrbytes);758	printk("sector address bytes: %u\n",    ns->geom.secaddrbytes);759	printk("options: %#x\n",                ns->options);760 761	ret = ns_alloc_device(ns);762	if (ret)763		goto free_partition_names;764 765	/* Allocate / initialize the internal buffer */766	ns->buf.byte = kmalloc(ns->geom.pgszoob, GFP_KERNEL);767	if (!ns->buf.byte) {768		NS_ERR("init_nandsim: unable to allocate %u bytes for the internal buffer\n",769			ns->geom.pgszoob);770		ret = -ENOMEM;771		goto free_device;772	}773	memset(ns->buf.byte, 0xFF, ns->geom.pgszoob);774 775	return 0;776 777free_device:778	ns_free_device(ns);779free_partition_names:780	for (i = 0; i < ARRAY_SIZE(ns->partitions); ++i)781		kfree(ns->partitions[i].name);782 783	return ret;784}785 786/*787 * Free the nandsim structure.788 */789static void ns_free(struct nandsim *ns)790{791	int i;792 793	for (i = 0; i < ARRAY_SIZE(ns->partitions); ++i)794		kfree(ns->partitions[i].name);795 796	kfree(ns->buf.byte);797	ns_free_device(ns);798 799	return;800}801 802static int ns_parse_badblocks(struct nandsim *ns, struct mtd_info *mtd)803{804	char *w;805	int zero_ok;806	unsigned int erase_block_no;807	loff_t offset;808 809	if (!badblocks)810		return 0;811	w = badblocks;812	do {813		zero_ok = (*w == '0' ? 1 : 0);814		erase_block_no = simple_strtoul(w, &w, 0);815		if (!zero_ok && !erase_block_no) {816			NS_ERR("invalid badblocks.\n");817			return -EINVAL;818		}819		offset = (loff_t)erase_block_no * ns->geom.secsz;820		if (mtd_block_markbad(mtd, offset)) {821			NS_ERR("invalid badblocks.\n");822			return -EINVAL;823		}824		if (*w == ',')825			w += 1;826	} while (*w);827	return 0;828}829 830static int ns_parse_weakblocks(void)831{832	char *w;833	int zero_ok;834	unsigned int erase_block_no;835	unsigned int max_erases;836	struct weak_block *wb;837 838	if (!weakblocks)839		return 0;840	w = weakblocks;841	do {842		zero_ok = (*w == '0' ? 1 : 0);843		erase_block_no = simple_strtoul(w, &w, 0);844		if (!zero_ok && !erase_block_no) {845			NS_ERR("invalid weakblocks.\n");846			return -EINVAL;847		}848		max_erases = 3;849		if (*w == ':') {850			w += 1;851			max_erases = simple_strtoul(w, &w, 0);852		}853		if (*w == ',')854			w += 1;855		wb = kzalloc(sizeof(*wb), GFP_KERNEL);856		if (!wb) {857			NS_ERR("unable to allocate memory.\n");858			return -ENOMEM;859		}860		wb->erase_block_no = erase_block_no;861		wb->max_erases = max_erases;862		list_add(&wb->list, &weak_blocks);863	} while (*w);864	return 0;865}866 867static int ns_erase_error(unsigned int erase_block_no)868{869	struct weak_block *wb;870 871	list_for_each_entry(wb, &weak_blocks, list)872		if (wb->erase_block_no == erase_block_no) {873			if (wb->erases_done >= wb->max_erases)874				return 1;875			wb->erases_done += 1;876			return 0;877		}878	return 0;879}880 881static int ns_parse_weakpages(void)882{883	char *w;884	int zero_ok;885	unsigned int page_no;886	unsigned int max_writes;887	struct weak_page *wp;888 889	if (!weakpages)890		return 0;891	w = weakpages;892	do {893		zero_ok = (*w == '0' ? 1 : 0);894		page_no = simple_strtoul(w, &w, 0);895		if (!zero_ok && !page_no) {896			NS_ERR("invalid weakpages.\n");897			return -EINVAL;898		}899		max_writes = 3;900		if (*w == ':') {901			w += 1;902			max_writes = simple_strtoul(w, &w, 0);903		}904		if (*w == ',')905			w += 1;906		wp = kzalloc(sizeof(*wp), GFP_KERNEL);907		if (!wp) {908			NS_ERR("unable to allocate memory.\n");909			return -ENOMEM;910		}911		wp->page_no = page_no;912		wp->max_writes = max_writes;913		list_add(&wp->list, &weak_pages);914	} while (*w);915	return 0;916}917 918static int ns_write_error(unsigned int page_no)919{920	struct weak_page *wp;921 922	list_for_each_entry(wp, &weak_pages, list)923		if (wp->page_no == page_no) {924			if (wp->writes_done >= wp->max_writes)925				return 1;926			wp->writes_done += 1;927			return 0;928		}929	return 0;930}931 932static int ns_parse_gravepages(void)933{934	char *g;935	int zero_ok;936	unsigned int page_no;937	unsigned int max_reads;938	struct grave_page *gp;939 940	if (!gravepages)941		return 0;942	g = gravepages;943	do {944		zero_ok = (*g == '0' ? 1 : 0);945		page_no = simple_strtoul(g, &g, 0);946		if (!zero_ok && !page_no) {947			NS_ERR("invalid gravepagess.\n");948			return -EINVAL;949		}950		max_reads = 3;951		if (*g == ':') {952			g += 1;953			max_reads = simple_strtoul(g, &g, 0);954		}955		if (*g == ',')956			g += 1;957		gp = kzalloc(sizeof(*gp), GFP_KERNEL);958		if (!gp) {959			NS_ERR("unable to allocate memory.\n");960			return -ENOMEM;961		}962		gp->page_no = page_no;963		gp->max_reads = max_reads;964		list_add(&gp->list, &grave_pages);965	} while (*g);966	return 0;967}968 969static int ns_read_error(unsigned int page_no)970{971	struct grave_page *gp;972 973	list_for_each_entry(gp, &grave_pages, list)974		if (gp->page_no == page_no) {975			if (gp->reads_done >= gp->max_reads)976				return 1;977			gp->reads_done += 1;978			return 0;979		}980	return 0;981}982 983static int ns_setup_wear_reporting(struct mtd_info *mtd)984{985	wear_eb_count = div_u64(mtd->size, mtd->erasesize);986	erase_block_wear = kcalloc(wear_eb_count, sizeof(unsigned long), GFP_KERNEL);987	if (!erase_block_wear) {988		NS_ERR("Too many erase blocks for wear reporting\n");989		return -ENOMEM;990	}991	return 0;992}993 994static void ns_update_wear(unsigned int erase_block_no)995{996	if (!erase_block_wear)997		return;998	total_wear += 1;999	/*1000	 * TODO: Notify this through a debugfs entry,1001	 * instead of showing an error message.1002	 */1003	if (total_wear == 0)1004		NS_ERR("Erase counter total overflow\n");1005	erase_block_wear[erase_block_no] += 1;1006	if (erase_block_wear[erase_block_no] == 0)1007		NS_ERR("Erase counter overflow for erase block %u\n", erase_block_no);1008}1009 1010/*1011 * Returns the string representation of 'state' state.1012 */1013static char *ns_get_state_name(uint32_t state)1014{1015	switch (NS_STATE(state)) {1016		case STATE_CMD_READ0:1017			return "STATE_CMD_READ0";1018		case STATE_CMD_READ1:1019			return "STATE_CMD_READ1";1020		case STATE_CMD_PAGEPROG:1021			return "STATE_CMD_PAGEPROG";1022		case STATE_CMD_READOOB:1023			return "STATE_CMD_READOOB";1024		case STATE_CMD_READSTART:1025			return "STATE_CMD_READSTART";1026		case STATE_CMD_ERASE1:1027			return "STATE_CMD_ERASE1";1028		case STATE_CMD_STATUS:1029			return "STATE_CMD_STATUS";1030		case STATE_CMD_SEQIN:1031			return "STATE_CMD_SEQIN";1032		case STATE_CMD_READID:1033			return "STATE_CMD_READID";1034		case STATE_CMD_ERASE2:1035			return "STATE_CMD_ERASE2";1036		case STATE_CMD_RESET:1037			return "STATE_CMD_RESET";1038		case STATE_CMD_RNDOUT:1039			return "STATE_CMD_RNDOUT";1040		case STATE_CMD_RNDOUTSTART:1041			return "STATE_CMD_RNDOUTSTART";1042		case STATE_ADDR_PAGE:1043			return "STATE_ADDR_PAGE";1044		case STATE_ADDR_SEC:1045			return "STATE_ADDR_SEC";1046		case STATE_ADDR_ZERO:1047			return "STATE_ADDR_ZERO";1048		case STATE_ADDR_COLUMN:1049			return "STATE_ADDR_COLUMN";1050		case STATE_DATAIN:1051			return "STATE_DATAIN";1052		case STATE_DATAOUT:1053			return "STATE_DATAOUT";1054		case STATE_DATAOUT_ID:1055			return "STATE_DATAOUT_ID";1056		case STATE_DATAOUT_STATUS:1057			return "STATE_DATAOUT_STATUS";1058		case STATE_READY:1059			return "STATE_READY";1060		case STATE_UNKNOWN:1061			return "STATE_UNKNOWN";1062	}1063 1064	NS_ERR("get_state_name: unknown state, BUG\n");1065	return NULL;1066}1067 1068/*1069 * Check if command is valid.1070 *1071 * RETURNS: 1 if wrong command, 0 if right.1072 */1073static int ns_check_command(int cmd)1074{1075	switch (cmd) {1076 1077	case NAND_CMD_READ0:1078	case NAND_CMD_READ1:1079	case NAND_CMD_READSTART:1080	case NAND_CMD_PAGEPROG:1081	case NAND_CMD_READOOB:1082	case NAND_CMD_ERASE1:1083	case NAND_CMD_STATUS:1084	case NAND_CMD_SEQIN:1085	case NAND_CMD_READID:1086	case NAND_CMD_ERASE2:1087	case NAND_CMD_RESET:1088	case NAND_CMD_RNDOUT:1089	case NAND_CMD_RNDOUTSTART:1090		return 0;1091 1092	default:1093		return 1;1094	}1095}1096 1097/*1098 * Returns state after command is accepted by command number.1099 */1100static uint32_t ns_get_state_by_command(unsigned command)1101{1102	switch (command) {1103		case NAND_CMD_READ0:1104			return STATE_CMD_READ0;1105		case NAND_CMD_READ1:1106			return STATE_CMD_READ1;1107		case NAND_CMD_PAGEPROG:1108			return STATE_CMD_PAGEPROG;1109		case NAND_CMD_READSTART:1110			return STATE_CMD_READSTART;1111		case NAND_CMD_READOOB:1112			return STATE_CMD_READOOB;1113		case NAND_CMD_ERASE1:1114			return STATE_CMD_ERASE1;1115		case NAND_CMD_STATUS:1116			return STATE_CMD_STATUS;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 */1138static inline void ns_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 */1156static inline void ns_switch_to_ready_state(struct nandsim *ns, u_char status)1157{1158	NS_DBG("switch_to_ready_state: switch to %s state\n",1159	       ns_get_state_name(STATE_READY));1160 1161	ns->state       = STATE_READY;1162	ns->nxstate     = STATE_UNKNOWN;1163	ns->op          = NULL;1164	ns->npstates    = 0;1165	ns->stateidx    = 0;1166	ns->regs.num    = 0;1167	ns->regs.count  = 0;1168	ns->regs.off    = 0;1169	ns->regs.row    = 0;1170	ns->regs.column = 0;1171	ns->regs.status = status;1172}1173 1174/*1175 * If the operation isn't known yet, try to find it in the global array1176 * of supported operations.1177 *1178 * Operation can be unknown because of the following.1179 *   1. New command was accepted and this is the first call to find the1180 *      correspondent states chain. In this case ns->npstates = 0;1181 *   2. There are several operations which begin with the same command(s)1182 *      (for example program from the second half and read from the1183 *      second half operations both begin with the READ1 command). In this1184 *      case the ns->pstates[] array contains previous states.1185 *1186 * Thus, the function tries to find operation containing the following1187 * states (if the 'flag' parameter is 0):1188 *    ns->pstates[0], ... ns->pstates[ns->npstates], ns->state1189 *1190 * If (one and only one) matching operation is found, it is accepted (1191 * ns->ops, ns->state, ns->nxstate are initialized, ns->npstate is1192 * zeroed).1193 *1194 * If there are several matches, the current state is pushed to the1195 * ns->pstates.1196 *1197 * The operation can be unknown only while commands are input to the chip.1198 * As soon as address command is accepted, the operation must be known.1199 * In such situation the function is called with 'flag' != 0, and the1200 * operation is searched using the following pattern:1201 *     ns->pstates[0], ... ns->pstates[ns->npstates], <address input>1202 *1203 * It is supposed that this pattern must either match one operation or1204 * none. There can't be ambiguity in that case.1205 *1206 * If no matches found, the function does the following:1207 *   1. if there are saved states present, try to ignore them and search1208 *      again only using the last command. If nothing was found, switch1209 *      to the STATE_READY state.1210 *   2. if there are no saved states, switch to the STATE_READY state.1211 *1212 * RETURNS: -2 - no matched operations found.1213 *          -1 - several matches.1214 *           0 - operation is found.1215 */1216static int ns_find_operation(struct nandsim *ns, uint32_t flag)1217{1218	int opsfound = 0;1219	int i, j, idx = 0;1220 1221	for (i = 0; i < NS_OPER_NUM; i++) {1222 1223		int found = 1;1224 1225		if (!(ns->options & ops[i].reqopts))1226			/* Ignore operations we can't perform */1227			continue;1228 1229		if (flag) {1230			if (!(ops[i].states[ns->npstates] & STATE_ADDR_MASK))1231				continue;1232		} else {1233			if (NS_STATE(ns->state) != NS_STATE(ops[i].states[ns->npstates]))1234				continue;1235		}1236 1237		for (j = 0; j < ns->npstates; j++)1238			if (NS_STATE(ops[i].states[j]) != NS_STATE(ns->pstates[j])1239				&& (ns->options & ops[idx].reqopts)) {1240				found = 0;1241				break;1242			}1243 1244		if (found) {1245			idx = i;1246			opsfound += 1;1247		}1248	}1249 1250	if (opsfound == 1) {1251		/* Exact match */1252		ns->op = &ops[idx].states[0];1253		if (flag) {1254			/*1255			 * In this case the find_operation function was1256			 * called when address has just began input. But it isn't1257			 * yet fully input and the current state must1258			 * not be one of STATE_ADDR_*, but the STATE_ADDR_*1259			 * state must be the next state (ns->nxstate).1260			 */1261			ns->stateidx = ns->npstates - 1;1262		} else {1263			ns->stateidx = ns->npstates;1264		}1265		ns->npstates = 0;1266		ns->state = ns->op[ns->stateidx];1267		ns->nxstate = ns->op[ns->stateidx + 1];1268		NS_DBG("find_operation: operation found, index: %d, state: %s, nxstate %s\n",1269		       idx, ns_get_state_name(ns->state),1270		       ns_get_state_name(ns->nxstate));1271		return 0;1272	}1273 1274	if (opsfound == 0) {1275		/* Nothing was found. Try to ignore previous commands (if any) and search again */1276		if (ns->npstates != 0) {1277			NS_DBG("find_operation: no operation found, try again with state %s\n",1278			       ns_get_state_name(ns->state));1279			ns->npstates = 0;1280			return ns_find_operation(ns, 0);1281 1282		}1283		NS_DBG("find_operation: no operations found\n");1284		ns_switch_to_ready_state(ns, NS_STATUS_FAILED(ns));1285		return -2;1286	}1287 1288	if (flag) {1289		/* This shouldn't happen */1290		NS_DBG("find_operation: BUG, operation must be known if address is input\n");1291		return -2;1292	}1293 1294	NS_DBG("find_operation: there is still ambiguity\n");1295 1296	ns->pstates[ns->npstates++] = ns->state;1297 1298	return -1;1299}1300 1301static void ns_put_pages(struct nandsim *ns)1302{1303	int i;1304 1305	for (i = 0; i < ns->held_cnt; i++)1306		put_page(ns->held_pages[i]);1307}1308 1309/* Get page cache pages in advance to provide NOFS memory allocation */1310static int ns_get_pages(struct nandsim *ns, struct file *file, size_t count,1311			loff_t pos)1312{1313	pgoff_t index, start_index, end_index;1314	struct page *page;1315	struct address_space *mapping = file->f_mapping;1316 1317	start_index = pos >> PAGE_SHIFT;1318	end_index = (pos + count - 1) >> PAGE_SHIFT;1319	if (end_index - start_index + 1 > NS_MAX_HELD_PAGES)1320		return -EINVAL;1321	ns->held_cnt = 0;1322	for (index = start_index; index <= end_index; index++) {1323		page = find_get_page(mapping, index);1324		if (page == NULL) {1325			page = find_or_create_page(mapping, index, GFP_NOFS);1326			if (page == NULL) {1327				write_inode_now(mapping->host, 1);1328				page = find_or_create_page(mapping, index, GFP_NOFS);1329			}1330			if (page == NULL) {1331				ns_put_pages(ns);1332				return -ENOMEM;1333			}1334			unlock_page(page);1335		}1336		ns->held_pages[ns->held_cnt++] = page;1337	}1338	return 0;1339}1340 1341static ssize_t ns_read_file(struct nandsim *ns, struct file *file, void *buf,1342			    size_t count, loff_t pos)1343{1344	ssize_t tx;1345	int err;1346	unsigned int noreclaim_flag;1347 1348	err = ns_get_pages(ns, file, count, pos);1349	if (err)1350		return err;1351	noreclaim_flag = memalloc_noreclaim_save();1352	tx = kernel_read(file, buf, count, &pos);1353	memalloc_noreclaim_restore(noreclaim_flag);1354	ns_put_pages(ns);1355	return tx;1356}1357 1358static ssize_t ns_write_file(struct nandsim *ns, struct file *file, void *buf,1359			     size_t count, loff_t pos)1360{1361	ssize_t tx;1362	int err;1363	unsigned int noreclaim_flag;1364 1365	err = ns_get_pages(ns, file, count, pos);1366	if (err)1367		return err;1368	noreclaim_flag = memalloc_noreclaim_save();1369	tx = kernel_write(file, buf, count, &pos);1370	memalloc_noreclaim_restore(noreclaim_flag);1371	ns_put_pages(ns);1372	return tx;1373}1374 1375/*1376 * Returns a pointer to the current page.1377 */1378static inline union ns_mem *NS_GET_PAGE(struct nandsim *ns)1379{1380	return &(ns->pages[ns->regs.row]);1381}1382 1383/*1384 * Returns a pointer to the current byte, within the current page.1385 */1386static inline u_char *NS_PAGE_BYTE_OFF(struct nandsim *ns)1387{1388	return NS_GET_PAGE(ns)->byte + NS_PAGE_BYTE_SHIFT(ns);1389}1390 1391static int ns_do_read_error(struct nandsim *ns, int num)1392{1393	unsigned int page_no = ns->regs.row;1394 1395	if (ns_read_error(page_no)) {1396		get_random_bytes(ns->buf.byte, num);1397		NS_WARN("simulating read error in page %u\n", page_no);1398		return 1;1399	}1400	return 0;1401}1402 1403static void ns_do_bit_flips(struct nandsim *ns, int num)1404{1405	if (bitflips && get_random_u16() < (1 << 6)) {1406		int flips = 1;1407		if (bitflips > 1)1408			flips = get_random_u32_inclusive(1, bitflips);1409		while (flips--) {1410			int pos = get_random_u32_below(num * 8);1411			ns->buf.byte[pos / 8] ^= (1 << (pos % 8));1412			NS_WARN("read_page: flipping bit %d in page %d "1413				"reading from %d ecc: corrected=%u failed=%u\n",1414				pos, ns->regs.row, NS_PAGE_BYTE_SHIFT(ns),1415				nsmtd->ecc_stats.corrected, nsmtd->ecc_stats.failed);1416		}1417	}1418}1419 1420/*1421 * Fill the NAND buffer with data read from the specified page.1422 */1423static void ns_read_page(struct nandsim *ns, int num)1424{1425	union ns_mem *mypage;1426 1427	if (ns->cfile) {1428		if (!test_bit(ns->regs.row, ns->pages_written)) {1429			NS_DBG("read_page: page %d not written\n", ns->regs.row);1430			memset(ns->buf.byte, 0xFF, num);1431		} else {1432			loff_t pos;1433			ssize_t tx;1434 1435			NS_DBG("read_page: page %d written, reading from %d\n",1436				ns->regs.row, NS_PAGE_BYTE_SHIFT(ns));1437			if (ns_do_read_error(ns, num))1438				return;1439			pos = (loff_t)NS_RAW_OFFSET(ns) + ns->regs.off;1440			tx = ns_read_file(ns, ns->cfile, ns->buf.byte, num,1441					  pos);1442			if (tx != num) {1443				NS_ERR("read_page: read error for page %d ret %ld\n", ns->regs.row, (long)tx);1444				return;1445			}1446			ns_do_bit_flips(ns, num);1447		}1448		return;1449	}1450 1451	mypage = NS_GET_PAGE(ns);1452	if (mypage->byte == NULL) {1453		NS_DBG("read_page: page %d not allocated\n", ns->regs.row);1454		memset(ns->buf.byte, 0xFF, num);1455	} else {1456		NS_DBG("read_page: page %d allocated, reading from %d\n",1457			ns->regs.row, NS_PAGE_BYTE_SHIFT(ns));1458		if (ns_do_read_error(ns, num))1459			return;1460		memcpy(ns->buf.byte, NS_PAGE_BYTE_OFF(ns), num);1461		ns_do_bit_flips(ns, num);1462	}1463}1464 1465/*1466 * Erase all pages in the specified sector.1467 */1468static void ns_erase_sector(struct nandsim *ns)1469{1470	union ns_mem *mypage;1471	int i;1472 1473	if (ns->cfile) {1474		for (i = 0; i < ns->geom.pgsec; i++)1475			if (__test_and_clear_bit(ns->regs.row + i,1476						 ns->pages_written)) {1477				NS_DBG("erase_sector: freeing page %d\n", ns->regs.row + i);1478			}1479		return;1480	}1481 1482	mypage = NS_GET_PAGE(ns);1483	for (i = 0; i < ns->geom.pgsec; i++) {1484		if (mypage->byte != NULL) {1485			NS_DBG("erase_sector: freeing page %d\n", ns->regs.row+i);1486			kmem_cache_free(ns->nand_pages_slab, mypage->byte);1487			mypage->byte = NULL;1488		}1489		mypage++;1490	}1491}1492 1493/*1494 * Program the specified page with the contents from the NAND buffer.1495 */1496static int ns_prog_page(struct nandsim *ns, int num)1497{1498	int i;1499	union ns_mem *mypage;1500	u_char *pg_off;1501 1502	if (ns->cfile) {1503		loff_t off;1504		ssize_t tx;1505		int all;1506 1507		NS_DBG("prog_page: writing page %d\n", ns->regs.row);1508		pg_off = ns->file_buf + NS_PAGE_BYTE_SHIFT(ns);1509		off = (loff_t)NS_RAW_OFFSET(ns) + ns->regs.off;1510		if (!test_bit(ns->regs.row, ns->pages_written)) {1511			all = 1;1512			memset(ns->file_buf, 0xff, ns->geom.pgszoob);1513		} else {1514			all = 0;1515			tx = ns_read_file(ns, ns->cfile, pg_off, num, off);1516			if (tx != num) {1517				NS_ERR("prog_page: read error for page %d ret %ld\n", ns->regs.row, (long)tx);1518				return -1;1519			}1520		}1521		for (i = 0; i < num; i++)1522			pg_off[i] &= ns->buf.byte[i];1523		if (all) {1524			loff_t pos = (loff_t)ns->regs.row * ns->geom.pgszoob;1525			tx = ns_write_file(ns, ns->cfile, ns->file_buf,1526					   ns->geom.pgszoob, pos);1527			if (tx != ns->geom.pgszoob) {1528				NS_ERR("prog_page: write error for page %d ret %ld\n", ns->regs.row, (long)tx);1529				return -1;1530			}1531			__set_bit(ns->regs.row, ns->pages_written);1532		} else {1533			tx = ns_write_file(ns, ns->cfile, pg_off, num, off);1534			if (tx != num) {1535				NS_ERR("prog_page: write error for page %d ret %ld\n", ns->regs.row, (long)tx);1536				return -1;1537			}1538		}1539		return 0;1540	}1541 1542	mypage = NS_GET_PAGE(ns);1543	if (mypage->byte == NULL) {1544		NS_DBG("prog_page: allocating page %d\n", ns->regs.row);1545		/*1546		 * We allocate memory with GFP_NOFS because a flash FS may1547		 * utilize this. If it is holding an FS lock, then gets here,1548		 * then kernel memory alloc runs writeback which goes to the FS1549		 * again and deadlocks. This was seen in practice.1550		 */1551		mypage->byte = kmem_cache_alloc(ns->nand_pages_slab, GFP_NOFS);1552		if (mypage->byte == NULL) {1553			NS_ERR("prog_page: error allocating memory for page %d\n", ns->regs.row);1554			return -1;1555		}1556		memset(mypage->byte, 0xFF, ns->geom.pgszoob);1557	}1558 1559	pg_off = NS_PAGE_BYTE_OFF(ns);1560	for (i = 0; i < num; i++)1561		pg_off[i] &= ns->buf.byte[i];1562 1563	return 0;1564}1565 1566/*1567 * If state has any action bit, perform this action.1568 *1569 * RETURNS: 0 if success, -1 if error.1570 */1571static int ns_do_state_action(struct nandsim *ns, uint32_t action)1572{1573	int num;1574	int busdiv = ns->busw == 8 ? 1 : 2;1575	unsigned int erase_block_no, page_no;1576 1577	action &= ACTION_MASK;1578 1579	/* Check that page address input is correct */1580	if (action != ACTION_SECERASE && ns->regs.row >= ns->geom.pgnum) {1581		NS_WARN("do_state_action: wrong page number (%#x)\n", ns->regs.row);1582		return -1;1583	}1584 1585	switch (action) {1586 1587	case ACTION_CPY:1588		/*1589		 * Copy page data to the internal buffer.1590		 */1591 1592		/* Column shouldn't be very large */1593		if (ns->regs.column >= (ns->geom.pgszoob - ns->regs.off)) {1594			NS_ERR("do_state_action: column number is too large\n");1595			break;1596		}1597		num = ns->geom.pgszoob - NS_PAGE_BYTE_SHIFT(ns);1598		ns_read_page(ns, num);1599 1600		NS_DBG("do_state_action: (ACTION_CPY:) copy %d bytes to int buf, raw offset %d\n",1601			num, NS_RAW_OFFSET(ns) + ns->regs.off);1602 1603		if (ns->regs.off == 0)1604			NS_LOG("read page %d\n", ns->regs.row);1605		else if (ns->regs.off < ns->geom.pgsz)1606			NS_LOG("read page %d (second half)\n", ns->regs.row);1607		else1608			NS_LOG("read OOB of page %d\n", ns->regs.row);1609 1610		NS_UDELAY(access_delay);1611		NS_UDELAY(input_cycle * ns->geom.pgsz / 1000 / busdiv);1612 1613		break;1614 1615	case ACTION_SECERASE:1616		/*1617		 * Erase sector.1618		 */1619 1620		if (ns->lines.wp) {1621			NS_ERR("do_state_action: device is write-protected, ignore sector erase\n");1622			return -1;1623		}1624 1625		if (ns->regs.row >= ns->geom.pgnum - ns->geom.pgsec1626			|| (ns->regs.row & ~(ns->geom.secsz - 1))) {1627			NS_ERR("do_state_action: wrong sector address (%#x)\n", ns->regs.row);1628			return -1;1629		}1630 1631		ns->regs.row = (ns->regs.row <<1632				8 * (ns->geom.pgaddrbytes - ns->geom.secaddrbytes)) | ns->regs.column;1633		ns->regs.column = 0;1634 1635		erase_block_no = ns->regs.row >> (ns->geom.secshift - ns->geom.pgshift);1636 1637		NS_DBG("do_state_action: erase sector at address %#x, off = %d\n",1638				ns->regs.row, NS_RAW_OFFSET(ns));1639		NS_LOG("erase sector %u\n", erase_block_no);1640 1641		ns_erase_sector(ns);1642 1643		NS_MDELAY(erase_delay);1644 1645		if (erase_block_wear)1646			ns_update_wear(erase_block_no);1647 1648		if (ns_erase_error(erase_block_no)) {1649			NS_WARN("simulating erase failure in erase block %u\n", erase_block_no);1650			return -1;1651		}1652 1653		break;1654 1655	case ACTION_PRGPAGE:1656		/*1657		 * Program page - move internal buffer data to the page.1658		 */1659 1660		if (ns->lines.wp) {1661			NS_WARN("do_state_action: device is write-protected, programm\n");1662			return -1;1663		}1664 1665		num = ns->geom.pgszoob - NS_PAGE_BYTE_SHIFT(ns);1666		if (num != ns->regs.count) {1667			NS_ERR("do_state_action: too few bytes were input (%d instead of %d)\n",1668					ns->regs.count, num);1669			return -1;1670		}1671 1672		if (ns_prog_page(ns, num) == -1)1673			return -1;1674 1675		page_no = ns->regs.row;1676 1677		NS_DBG("do_state_action: copy %d bytes from int buf to (%#x, %#x), raw off = %d\n",1678			num, ns->regs.row, ns->regs.column, NS_RAW_OFFSET(ns) + ns->regs.off);1679		NS_LOG("programm page %d\n", ns->regs.row);1680 1681		NS_UDELAY(programm_delay);1682		NS_UDELAY(output_cycle * ns->geom.pgsz / 1000 / busdiv);1683 1684		if (ns_write_error(page_no)) {1685			NS_WARN("simulating write failure in page %u\n", page_no);1686			return -1;1687		}1688 1689		break;1690 1691	case ACTION_ZEROOFF:1692		NS_DBG("do_state_action: set internal offset to 0\n");1693		ns->regs.off = 0;1694		break;1695 1696	case ACTION_HALFOFF:1697		if (!(ns->options & OPT_PAGE512_8BIT)) {1698			NS_ERR("do_state_action: BUG! can't skip half of page for non-512"1699				"byte page size 8x chips\n");1700			return -1;1701		}1702		NS_DBG("do_state_action: set internal offset to %d\n", ns->geom.pgsz/2);1703		ns->regs.off = ns->geom.pgsz/2;1704		break;1705 1706	case ACTION_OOBOFF:1707		NS_DBG("do_state_action: set internal offset to %d\n", ns->geom.pgsz);1708		ns->regs.off = ns->geom.pgsz;1709		break;1710 1711	default:1712		NS_DBG("do_state_action: BUG! unknown action\n");1713	}1714 1715	return 0;1716}1717 1718/*1719 * Switch simulator's state.1720 */1721static void ns_switch_state(struct nandsim *ns)1722{1723	if (ns->op) {1724		/*1725		 * The current operation have already been identified.1726		 * Just follow the states chain.1727		 */1728 1729		ns->stateidx += 1;1730		ns->state = ns->nxstate;1731		ns->nxstate = ns->op[ns->stateidx + 1];1732 1733		NS_DBG("switch_state: operation is known, switch to the next state, "1734			"state: %s, nxstate: %s\n",1735		       ns_get_state_name(ns->state),1736		       ns_get_state_name(ns->nxstate));1737	} else {1738		/*1739		 * We don't yet know which operation we perform.1740		 * Try to identify it.1741		 */1742 1743		/*1744		 *  The only event causing the switch_state function to1745		 *  be called with yet unknown operation is new command.1746		 */1747		ns->state = ns_get_state_by_command(ns->regs.command);1748 1749		NS_DBG("switch_state: operation is unknown, try to find it\n");1750 1751		if (ns_find_operation(ns, 0))1752			return;1753	}1754 1755	/* See, whether we need to do some action */1756	if ((ns->state & ACTION_MASK) &&1757	    ns_do_state_action(ns, ns->state) < 0) {1758		ns_switch_to_ready_state(ns, NS_STATUS_FAILED(ns));1759		return;1760	}1761 1762	/* For 16x devices column means the page offset in words */1763	if ((ns->nxstate & STATE_ADDR_MASK) && ns->busw == 16) {1764		NS_DBG("switch_state: double the column number for 16x device\n");1765		ns->regs.column <<= 1;1766	}1767 1768	if (NS_STATE(ns->nxstate) == STATE_READY) {1769		/*1770		 * The current state is the last. Return to STATE_READY1771		 */1772 1773		u_char status = NS_STATUS_OK(ns);1774 1775		/* In case of data states, see if all bytes were input/output */1776		if ((ns->state & (STATE_DATAIN_MASK | STATE_DATAOUT_MASK))1777			&& ns->regs.count != ns->regs.num) {1778			NS_WARN("switch_state: not all bytes were processed, %d left\n",1779					ns->regs.num - ns->regs.count);1780			status = NS_STATUS_FAILED(ns);1781		}1782 1783		NS_DBG("switch_state: operation complete, switch to STATE_READY state\n");1784 1785		ns_switch_to_ready_state(ns, status);1786 1787		return;1788	} else if (ns->nxstate & (STATE_DATAIN_MASK | STATE_DATAOUT_MASK)) {1789		/*1790		 * If the next state is data input/output, switch to it now1791		 */1792 1793		ns->state      = ns->nxstate;1794		ns->nxstate    = ns->op[++ns->stateidx + 1];1795		ns->regs.num   = ns->regs.count = 0;1796 1797		NS_DBG("switch_state: the next state is data I/O, switch, "1798			"state: %s, nxstate: %s\n",1799		       ns_get_state_name(ns->state),1800		       ns_get_state_name(ns->nxstate));1801 1802		/*1803		 * Set the internal register to the count of bytes which1804		 * are expected to be input or output1805		 */1806		switch (NS_STATE(ns->state)) {1807			case STATE_DATAIN:1808			case STATE_DATAOUT:1809				ns->regs.num = ns->geom.pgszoob - NS_PAGE_BYTE_SHIFT(ns);1810				break;1811 1812			case STATE_DATAOUT_ID:1813				ns->regs.num = ns->geom.idbytes;1814				break;1815 1816			case STATE_DATAOUT_STATUS:1817				ns->regs.count = ns->regs.num = 0;1818				break;1819 1820			default:1821				NS_ERR("switch_state: BUG! unknown data state\n");1822		}1823 1824	} else if (ns->nxstate & STATE_ADDR_MASK) {1825		/*1826		 * If the next state is address input, set the internal1827		 * register to the number of expected address bytes1828		 */1829 1830		ns->regs.count = 0;1831 1832		switch (NS_STATE(ns->nxstate)) {1833			case STATE_ADDR_PAGE:1834				ns->regs.num = ns->geom.pgaddrbytes;1835 1836				break;1837			case STATE_ADDR_SEC:1838				ns->regs.num = ns->geom.secaddrbytes;1839				break;1840 1841			case STATE_ADDR_ZERO:1842				ns->regs.num = 1;1843				break;1844 1845			case STATE_ADDR_COLUMN:1846				/* Column address is always 2 bytes */1847				ns->regs.num = ns->geom.pgaddrbytes - ns->geom.secaddrbytes;1848				break;1849 1850			default:1851				NS_ERR("switch_state: BUG! unknown address state\n");1852		}1853	} else {1854		/*1855		 * Just reset internal counters.1856		 */1857 1858		ns->regs.num = 0;1859		ns->regs.count = 0;1860	}1861}1862 1863static u_char ns_nand_read_byte(struct nand_chip *chip)1864{1865	struct nandsim *ns = nand_get_controller_data(chip);1866	u_char outb = 0x00;1867 1868	/* Sanity and correctness checks */1869	if (!ns->lines.ce) {1870		NS_ERR("read_byte: chip is disabled, return %#x\n", (uint)outb);1871		return outb;1872	}1873	if (ns->lines.ale || ns->lines.cle) {1874		NS_ERR("read_byte: ALE or CLE pin is high, return %#x\n", (uint)outb);1875		return outb;1876	}1877	if (!(ns->state & STATE_DATAOUT_MASK)) {1878		NS_WARN("read_byte: unexpected data output cycle, state is %s return %#x\n",1879			ns_get_state_name(ns->state), (uint)outb);1880		return outb;1881	}1882 1883	/* Status register may be read as many times as it is wanted */1884	if (NS_STATE(ns->state) == STATE_DATAOUT_STATUS) {1885		NS_DBG("read_byte: return %#x status\n", ns->regs.status);1886		return ns->regs.status;1887	}1888 1889	/* Check if there is any data in the internal buffer which may be read */1890	if (ns->regs.count == ns->regs.num) {1891		NS_WARN("read_byte: no more data to output, return %#x\n", (uint)outb);1892		return outb;1893	}1894 1895	switch (NS_STATE(ns->state)) {1896		case STATE_DATAOUT:1897			if (ns->busw == 8) {1898				outb = ns->buf.byte[ns->regs.count];1899				ns->regs.count += 1;1900			} else {1901				outb = (u_char)cpu_to_le16(ns->buf.word[ns->regs.count >> 1]);1902				ns->regs.count += 2;1903			}1904			break;1905		case STATE_DATAOUT_ID:1906			NS_DBG("read_byte: read ID byte %d, total = %d\n", ns->regs.count, ns->regs.num);1907			outb = ns->ids[ns->regs.count];1908			ns->regs.count += 1;1909			break;1910		default:1911			BUG();1912	}1913 1914	if (ns->regs.count == ns->regs.num) {1915		NS_DBG("read_byte: all bytes were read\n");1916 1917		if (NS_STATE(ns->nxstate) == STATE_READY)1918			ns_switch_state(ns);1919	}1920 1921	return outb;1922}1923 1924static void ns_nand_write_byte(struct nand_chip *chip, u_char byte)1925{1926	struct nandsim *ns = nand_get_controller_data(chip);1927 1928	/* Sanity and correctness checks */1929	if (!ns->lines.ce) {1930		NS_ERR("write_byte: chip is disabled, ignore write\n");1931		return;1932	}1933	if (ns->lines.ale && ns->lines.cle) {1934		NS_ERR("write_byte: ALE and CLE pins are high simultaneously, ignore write\n");1935		return;1936	}1937 1938	if (ns->lines.cle == 1) {1939		/*1940		 * The byte written is a command.1941		 */1942 1943		if (byte == NAND_CMD_RESET) {1944			NS_LOG("reset chip\n");1945			ns_switch_to_ready_state(ns, NS_STATUS_OK(ns));1946			return;1947		}1948 1949		/* Check that the command byte is correct */1950		if (ns_check_command(byte)) {1951			NS_ERR("write_byte: unknown command %#x\n", (uint)byte);1952			return;1953		}1954 1955		if (NS_STATE(ns->state) == STATE_DATAOUT_STATUS1956			|| NS_STATE(ns->state) == STATE_DATAOUT) {1957			int row = ns->regs.row;1958 1959			ns_switch_state(ns);1960			if (byte == NAND_CMD_RNDOUT)1961				ns->regs.row = row;1962		}1963 1964		/* Check if chip is expecting command */1965		if (NS_STATE(ns->nxstate) != STATE_UNKNOWN && !(ns->nxstate & STATE_CMD_MASK)) {1966			/* Do not warn if only 2 id bytes are read */1967			if (!(ns->regs.command == NAND_CMD_READID &&1968			    NS_STATE(ns->state) == STATE_DATAOUT_ID && ns->regs.count == 2)) {1969				/*1970				 * We are in situation when something else (not command)1971				 * was expected but command was input. In this case ignore1972				 * previous command(s)/state(s) and accept the last one.1973				 */1974				NS_WARN("write_byte: command (%#x) wasn't expected, expected state is %s, ignore previous states\n",1975					(uint)byte,1976					ns_get_state_name(ns->nxstate));1977			}1978			ns_switch_to_ready_state(ns, NS_STATUS_FAILED(ns));1979		}1980 1981		NS_DBG("command byte corresponding to %s state accepted\n",1982			ns_get_state_name(ns_get_state_by_command(byte)));1983		ns->regs.command = byte;1984		ns_switch_state(ns);1985 1986	} else if (ns->lines.ale == 1) {1987		/*1988		 * The byte written is an address.1989		 */1990 1991		if (NS_STATE(ns->nxstate) == STATE_UNKNOWN) {1992 1993			NS_DBG("write_byte: operation isn't known yet, identify it\n");1994 1995			if (ns_find_operation(ns, 1) < 0)1996				return;1997 1998			if ((ns->state & ACTION_MASK) &&1999			    ns_do_state_action(ns, ns->state) < 0) {2000				ns_switch_to_ready_state(ns,2001							 NS_STATUS_FAILED(ns));2002				return;2003			}2004 2005			ns->regs.count = 0;2006			switch (NS_STATE(ns->nxstate)) {2007				case STATE_ADDR_PAGE:2008					ns->regs.num = ns->geom.pgaddrbytes;2009					break;2010				case STATE_ADDR_SEC:2011					ns->regs.num = ns->geom.secaddrbytes;2012					break;2013				case STATE_ADDR_ZERO:2014					ns->regs.num = 1;2015					break;2016				default:2017					BUG();2018			}2019		}2020 2021		/* Check that chip is expecting address */2022		if (!(ns->nxstate & STATE_ADDR_MASK)) {2023			NS_ERR("write_byte: address (%#x) isn't expected, expected state is %s, switch to STATE_READY\n",2024			       (uint)byte, ns_get_state_name(ns->nxstate));2025			ns_switch_to_ready_state(ns, NS_STATUS_FAILED(ns));2026			return;2027		}2028 2029		/* Check if this is expected byte */2030		if (ns->regs.count == ns->regs.num) {2031			NS_ERR("write_byte: no more address bytes expected\n");2032			ns_switch_to_ready_state(ns, NS_STATUS_FAILED(ns));2033			return;2034		}2035 2036		ns_accept_addr_byte(ns, byte);2037 2038		ns->regs.count += 1;2039 2040		NS_DBG("write_byte: address byte %#x was accepted (%d bytes input, %d expected)\n",2041				(uint)byte, ns->regs.count, ns->regs.num);2042 2043		if (ns->regs.count == ns->regs.num) {2044			NS_DBG("address (%#x, %#x) is accepted\n", ns->regs.row, ns->regs.column);2045			ns_switch_state(ns);2046		}2047 2048	} else {2049		/*2050		 * The byte written is an input data.2051		 */2052 2053		/* Check that chip is expecting data input */2054		if (!(ns->state & STATE_DATAIN_MASK)) {2055			NS_ERR("write_byte: data input (%#x) isn't expected, state is %s, switch to %s\n",2056			       (uint)byte, ns_get_state_name(ns->state),2057			       ns_get_state_name(STATE_READY));2058			ns_switch_to_ready_state(ns, NS_STATUS_FAILED(ns));2059			return;2060		}2061 2062		/* Check if this is expected byte */2063		if (ns->regs.count == ns->regs.num) {2064			NS_WARN("write_byte: %u input bytes has already been accepted, ignore write\n",2065					ns->regs.num);2066			return;2067		}2068 2069		if (ns->busw == 8) {2070			ns->buf.byte[ns->regs.count] = byte;2071			ns->regs.count += 1;2072		} else {2073			ns->buf.word[ns->regs.count >> 1] = cpu_to_le16((uint16_t)byte);2074			ns->regs.count += 2;2075		}2076	}2077 2078	return;2079}2080 2081static void ns_nand_write_buf(struct nand_chip *chip, const u_char *buf,2082			      int len)2083{2084	struct nandsim *ns = nand_get_controller_data(chip);2085 2086	/* Check that chip is expecting data input */2087	if (!(ns->state & STATE_DATAIN_MASK)) {2088		NS_ERR("write_buf: data input isn't expected, state is %s, switch to STATE_READY\n",2089		       ns_get_state_name(ns->state));2090		ns_switch_to_ready_state(ns, NS_STATUS_FAILED(ns));2091		return;2092	}2093 2094	/* Check if these are expected bytes */2095	if (ns->regs.count + len > ns->regs.num) {2096		NS_ERR("write_buf: too many input bytes\n");2097		ns_switch_to_ready_state(ns, NS_STATUS_FAILED(ns));2098		return;2099	}2100 2101	memcpy(ns->buf.byte + ns->regs.count, buf, len);2102	ns->regs.count += len;2103 2104	if (ns->regs.count == ns->regs.num) {2105		NS_DBG("write_buf: %d bytes were written\n", ns->regs.count);2106	}2107}2108 2109static void ns_nand_read_buf(struct nand_chip *chip, u_char *buf, int len)2110{2111	struct nandsim *ns = nand_get_controller_data(chip);2112 2113	/* Sanity and correctness checks */2114	if (!ns->lines.ce) {2115		NS_ERR("read_buf: chip is disabled\n");2116		return;2117	}2118	if (ns->lines.ale || ns->lines.cle) {2119		NS_ERR("read_buf: ALE or CLE pin is high\n");2120		return;2121	}2122	if (!(ns->state & STATE_DATAOUT_MASK)) {2123		NS_WARN("read_buf: unexpected data output cycle, current state is %s\n",2124			ns_get_state_name(ns->state));2125		return;2126	}2127 2128	if (NS_STATE(ns->state) != STATE_DATAOUT) {2129		int i;2130 2131		for (i = 0; i < len; i++)2132			buf[i] = ns_nand_read_byte(chip);2133 2134		return;2135	}2136 2137	/* Check if these are expected bytes */2138	if (ns->regs.count + len > ns->regs.num) {2139		NS_ERR("read_buf: too many bytes to read\n");2140		ns_switch_to_ready_state(ns, NS_STATUS_FAILED(ns));2141		return;2142	}2143 2144	memcpy(buf, ns->buf.byte + ns->regs.count, len);2145	ns->regs.count += len;2146 2147	if (ns->regs.count == ns->regs.num) {2148		if (NS_STATE(ns->nxstate) == STATE_READY)2149			ns_switch_state(ns);2150	}2151 2152	return;2153}2154 2155static int ns_exec_op(struct nand_chip *chip, const struct nand_operation *op,2156		      bool check_only)2157{2158	int i;2159	unsigned int op_id;2160	const struct nand_op_instr *instr = NULL;2161	struct nandsim *ns = nand_get_controller_data(chip);2162 2163	if (check_only) {2164		/* The current implementation of nandsim needs to know the2165		 * ongoing operation when performing the address cycles. This2166		 * means it cannot make the difference between a regular read2167		 * and a continuous read. Hence, this hack to manually refuse2168		 * supporting sequential cached operations.2169		 */2170		for (op_id = 0; op_id < op->ninstrs; op_id++) {2171			instr = &op->instrs[op_id];2172			if (instr->type == NAND_OP_CMD_INSTR &&2173			    (instr->ctx.cmd.opcode == NAND_CMD_READCACHEEND ||2174			     instr->ctx.cmd.opcode == NAND_CMD_READCACHESEQ))2175				return -EOPNOTSUPP;2176		}2177 2178		return 0;2179	}2180 2181	ns->lines.ce = 1;2182 2183	for (op_id = 0; op_id < op->ninstrs; op_id++) {2184		instr = &op->instrs[op_id];2185		ns->lines.cle = 0;2186		ns->lines.ale = 0;2187 2188		switch (instr->type) {2189		case NAND_OP_CMD_INSTR:2190			ns->lines.cle = 1;2191			ns_nand_write_byte(chip, instr->ctx.cmd.opcode);2192			break;2193		case NAND_OP_ADDR_INSTR:2194			ns->lines.ale = 1;2195			for (i = 0; i < instr->ctx.addr.naddrs; i++)2196				ns_nand_write_byte(chip, instr->ctx.addr.addrs[i]);2197			break;2198		case NAND_OP_DATA_IN_INSTR:2199			ns_nand_read_buf(chip, instr->ctx.data.buf.in, instr->ctx.data.len);2200			break;2201		case NAND_OP_DATA_OUT_INSTR:2202			ns_nand_write_buf(chip, instr->ctx.data.buf.out, instr->ctx.data.len);2203			break;2204		case NAND_OP_WAITRDY_INSTR:2205			/* we are always ready */2206			break;2207		}2208	}2209 2210	return 0;2211}2212 2213static int ns_attach_chip(struct nand_chip *chip)2214{2215	unsigned int eccsteps, eccbytes;2216 2217	chip->ecc.engine_type = NAND_ECC_ENGINE_TYPE_SOFT;2218	chip->ecc.algo = bch ? NAND_ECC_ALGO_BCH : NAND_ECC_ALGO_HAMMING;2219 2220	if (!bch)2221		return 0;2222 2223	if (!IS_ENABLED(CONFIG_MTD_NAND_ECC_SW_BCH)) {2224		NS_ERR("BCH ECC support is disabled\n");2225		return -EINVAL;2226	}2227 2228	/* Use 512-byte ecc blocks */2229	eccsteps = nsmtd->writesize / 512;2230	eccbytes = ((bch * 13) + 7) / 8;2231 2232	/* Do not bother supporting small page devices */2233	if (nsmtd->oobsize < 64 || !eccsteps) {2234		NS_ERR("BCH not available on small page devices\n");2235		return -EINVAL;2236	}2237 2238	if (((eccbytes * eccsteps) + 2) > nsmtd->oobsize) {2239		NS_ERR("Invalid BCH value %u\n", bch);2240		return -EINVAL;2241	}2242 2243	chip->ecc.size = 512;2244	chip->ecc.strength = bch;2245	chip->ecc.bytes = eccbytes;2246 2247	NS_INFO("Using %u-bit/%u bytes BCH ECC\n", bch, chip->ecc.size);2248 2249	return 0;2250}2251 2252static const struct nand_controller_ops ns_controller_ops = {2253	.attach_chip = ns_attach_chip,2254	.exec_op = ns_exec_op,2255};2256 2257/*2258 * Module initialization function2259 */2260static int __init ns_init_module(void)2261{2262	struct list_head *pos, *n;2263	struct nand_chip *chip;2264	struct nandsim *ns;2265	int ret;2266 2267	if (bus_width != 8 && bus_width != 16) {2268		NS_ERR("wrong bus width (%d), use only 8 or 16\n", bus_width);2269		return -EINVAL;2270	}2271 2272	ns = kzalloc(sizeof(struct nandsim), GFP_KERNEL);2273	if (!ns) {2274		NS_ERR("unable to allocate core structures.\n");2275		return -ENOMEM;2276	}2277	chip	    = &ns->chip;2278	nsmtd       = nand_to_mtd(chip);2279	nand_set_controller_data(chip, (void *)ns);2280 2281	/* The NAND_SKIP_BBTSCAN option is necessary for 'overridesize' */2282	/* and 'badblocks' parameters to work */2283	chip->options   |= NAND_SKIP_BBTSCAN;2284 2285	switch (bbt) {2286	case 2:2287		chip->bbt_options |= NAND_BBT_NO_OOB;2288		fallthrough;2289	case 1:2290		chip->bbt_options |= NAND_BBT_USE_FLASH;2291		fallthrough;2292	case 0:2293		break;2294	default:2295		NS_ERR("bbt has to be 0..2\n");2296		ret = -EINVAL;2297		goto free_ns_struct;2298	}2299	/*2300	 * Perform minimum nandsim structure initialization to handle2301	 * the initial ID read command correctly2302	 */2303	if (id_bytes[6] != 0xFF || id_bytes[7] != 0xFF)2304		ns->geom.idbytes = 8;2305	else if (id_bytes[4] != 0xFF || id_bytes[5] != 0xFF)2306		ns->geom.idbytes = 6;2307	else if (id_bytes[2] != 0xFF || id_bytes[3] != 0xFF)2308		ns->geom.idbytes = 4;2309	else2310		ns->geom.idbytes = 2;2311	ns->regs.status = NS_STATUS_OK(ns);2312	ns->nxstate = STATE_UNKNOWN;2313	ns->options |= OPT_PAGE512; /* temporary value */2314	memcpy(ns->ids, id_bytes, sizeof(ns->ids));2315	if (bus_width == 16) {2316		ns->busw = 16;2317		chip->options |= NAND_BUSWIDTH_16;2318	}2319 2320	nsmtd->owner = THIS_MODULE;2321 2322	ret = ns_parse_weakblocks();2323	if (ret)2324		goto free_ns_struct;2325 2326	ret = ns_parse_weakpages();2327	if (ret)2328		goto free_wb_list;2329 2330	ret = ns_parse_gravepages();2331	if (ret)2332		goto free_wp_list;2333 2334	nand_controller_init(&ns->base);2335	ns->base.ops = &ns_controller_ops;2336	chip->controller = &ns->base;2337 2338	ret = nand_scan(chip, 1);2339	if (ret) {2340		NS_ERR("Could not scan NAND Simulator device\n");2341		goto free_gp_list;2342	}2343 2344	if (overridesize) {2345		uint64_t new_size = (uint64_t)nsmtd->erasesize << overridesize;2346		struct nand_memory_organization *memorg;2347		u64 targetsize;2348 2349		memorg = nanddev_get_memorg(&chip->base);2350 2351		if (new_size >> overridesize != nsmtd->erasesize) {2352			NS_ERR("overridesize is too big\n");2353			ret = -EINVAL;2354			goto cleanup_nand;2355		}2356 2357		/* N.B. This relies on nand_scan not doing anything with the size before we change it */2358		nsmtd->size = new_size;2359		memorg->eraseblocks_per_lun = 1 << overridesize;2360		targetsize = nanddev_target_size(&chip->base);2361		chip->chip_shift = ffs(nsmtd->erasesize) + overridesize - 1;2362		chip->pagemask = (targetsize >> chip->page_shift) - 1;2363	}2364 2365	ret = ns_setup_wear_reporting(nsmtd);2366	if (ret)2367		goto cleanup_nand;2368 2369	ret = ns_init(nsmtd);2370	if (ret)2371		goto free_ebw;2372 2373	ret = nand_create_bbt(chip);2374	if (ret)2375		goto free_ns_object;2376 2377	ret = ns_parse_badblocks(ns, nsmtd);2378	if (ret)2379		goto free_ns_object;2380 2381	/* Register NAND partitions */2382	ret = mtd_device_register(nsmtd, &ns->partitions[0], ns->nbparts);2383	if (ret)2384		goto free_ns_object;2385 2386	ret = ns_debugfs_create(ns);2387	if (ret)2388		goto unregister_mtd;2389 2390        return 0;2391 2392unregister_mtd:2393	WARN_ON(mtd_device_unregister(nsmtd));2394free_ns_object:2395	ns_free(ns);2396free_ebw:2397	kfree(erase_block_wear);2398cleanup_nand:2399	nand_cleanup(chip);2400free_gp_list:2401	list_for_each_safe(pos, n, &grave_pages) {2402		list_del(pos);2403		kfree(list_entry(pos, struct grave_page, list));2404	}2405free_wp_list:2406	list_for_each_safe(pos, n, &weak_pages) {2407		list_del(pos);2408		kfree(list_entry(pos, struct weak_page, list));2409	}2410free_wb_list:2411	list_for_each_safe(pos, n, &weak_blocks) {2412		list_del(pos);2413		kfree(list_entry(pos, struct weak_block, list));2414	}2415free_ns_struct:2416	kfree(ns);2417 2418	return ret;2419}2420 2421module_init(ns_init_module);2422 2423/*2424 * Module clean-up function2425 */2426static void __exit ns_cleanup_module(void)2427{2428	struct nand_chip *chip = mtd_to_nand(nsmtd);2429	struct nandsim *ns = nand_get_controller_data(chip);2430	struct list_head *pos, *n;2431 2432	ns_debugfs_remove(ns);2433	WARN_ON(mtd_device_unregister(nsmtd));2434	ns_free(ns);2435	kfree(erase_block_wear);2436	nand_cleanup(chip);2437 2438	list_for_each_safe(pos, n, &grave_pages) {2439		list_del(pos);2440		kfree(list_entry(pos, struct grave_page, list));2441	}2442 2443	list_for_each_safe(pos, n, &weak_pages) {2444		list_del(pos);2445		kfree(list_entry(pos, struct weak_page, list));2446	}2447 2448	list_for_each_safe(pos, n, &weak_blocks) {2449		list_del(pos);2450		kfree(list_entry(pos, struct weak_block, list));2451	}2452 2453	kfree(ns);2454}2455 2456module_exit(ns_cleanup_module);2457 2458MODULE_LICENSE ("GPL");2459MODULE_AUTHOR ("Artem B. Bityuckiy");2460MODULE_DESCRIPTION ("The NAND flash simulator");2461