diff options
Diffstat (limited to 'drivers/mtd/nand/raw/nandsim.c')
| -rw-r--r-- | drivers/mtd/nand/raw/nandsim.c | 2392 |
1 files changed, 2392 insertions, 0 deletions
diff --git a/drivers/mtd/nand/raw/nandsim.c b/drivers/mtd/nand/raw/nandsim.c new file mode 100644 index 000000000000..44322a363ba5 --- /dev/null +++ b/drivers/mtd/nand/raw/nandsim.c @@ -0,0 +1,2392 @@ +/* + * NAND flash simulator. + * + * Author: Artem B. Bityuckiy <dedekind@oktetlabs.ru>, <dedekind@infradead.org> + * + * Copyright (C) 2004 Nokia Corporation + * + * Note: NS means "NAND Simulator". + * Note: Input means input TO flash chip, output means output FROM chip. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2, or (at your option) any later + * version. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General + * Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA + */ + +#include <linux/init.h> +#include <linux/types.h> +#include <linux/module.h> +#include <linux/moduleparam.h> +#include <linux/vmalloc.h> +#include <linux/math64.h> +#include <linux/slab.h> +#include <linux/errno.h> +#include <linux/string.h> +#include <linux/mtd/mtd.h> +#include <linux/mtd/rawnand.h> +#include <linux/mtd/nand_bch.h> +#include <linux/mtd/partitions.h> +#include <linux/delay.h> +#include <linux/list.h> +#include <linux/random.h> +#include <linux/sched.h> +#include <linux/sched/mm.h> +#include <linux/fs.h> +#include <linux/pagemap.h> +#include <linux/seq_file.h> +#include <linux/debugfs.h> + +/* Default simulator parameters values */ +#if !defined(CONFIG_NANDSIM_FIRST_ID_BYTE) || \ + !defined(CONFIG_NANDSIM_SECOND_ID_BYTE) || \ + !defined(CONFIG_NANDSIM_THIRD_ID_BYTE) || \ + !defined(CONFIG_NANDSIM_FOURTH_ID_BYTE) +#define CONFIG_NANDSIM_FIRST_ID_BYTE 0x98 +#define CONFIG_NANDSIM_SECOND_ID_BYTE 0x39 +#define CONFIG_NANDSIM_THIRD_ID_BYTE 0xFF /* No byte */ +#define CONFIG_NANDSIM_FOURTH_ID_BYTE 0xFF /* No byte */ +#endif + +#ifndef CONFIG_NANDSIM_ACCESS_DELAY +#define CONFIG_NANDSIM_ACCESS_DELAY 25 +#endif +#ifndef CONFIG_NANDSIM_PROGRAMM_DELAY +#define CONFIG_NANDSIM_PROGRAMM_DELAY 200 +#endif +#ifndef CONFIG_NANDSIM_ERASE_DELAY +#define CONFIG_NANDSIM_ERASE_DELAY 2 +#endif +#ifndef CONFIG_NANDSIM_OUTPUT_CYCLE +#define CONFIG_NANDSIM_OUTPUT_CYCLE 40 +#endif +#ifndef CONFIG_NANDSIM_INPUT_CYCLE +#define CONFIG_NANDSIM_INPUT_CYCLE 50 +#endif +#ifndef CONFIG_NANDSIM_BUS_WIDTH +#define CONFIG_NANDSIM_BUS_WIDTH 8 +#endif +#ifndef CONFIG_NANDSIM_DO_DELAYS +#define CONFIG_NANDSIM_DO_DELAYS 0 +#endif +#ifndef CONFIG_NANDSIM_LOG +#define CONFIG_NANDSIM_LOG 0 +#endif +#ifndef CONFIG_NANDSIM_DBG +#define CONFIG_NANDSIM_DBG 0 +#endif +#ifndef CONFIG_NANDSIM_MAX_PARTS +#define CONFIG_NANDSIM_MAX_PARTS 32 +#endif + +static uint access_delay = CONFIG_NANDSIM_ACCESS_DELAY; +static uint programm_delay = CONFIG_NANDSIM_PROGRAMM_DELAY; +static uint erase_delay = CONFIG_NANDSIM_ERASE_DELAY; +static uint output_cycle = CONFIG_NANDSIM_OUTPUT_CYCLE; +static uint input_cycle = CONFIG_NANDSIM_INPUT_CYCLE; +static uint bus_width = CONFIG_NANDSIM_BUS_WIDTH; +static uint do_delays = CONFIG_NANDSIM_DO_DELAYS; +static uint log = CONFIG_NANDSIM_LOG; +static uint dbg = CONFIG_NANDSIM_DBG; +static unsigned long parts[CONFIG_NANDSIM_MAX_PARTS]; +static unsigned int parts_num; +static char *badblocks = NULL; +static char *weakblocks = NULL; +static char *weakpages = NULL; +static unsigned int bitflips = 0; +static char *gravepages = NULL; +static unsigned int overridesize = 0; +static char *cache_file = NULL; +static unsigned int bbt; +static unsigned int bch; +static u_char id_bytes[8] = { + [0] = CONFIG_NANDSIM_FIRST_ID_BYTE, + [1] = CONFIG_NANDSIM_SECOND_ID_BYTE, + [2] = CONFIG_NANDSIM_THIRD_ID_BYTE, + [3] = CONFIG_NANDSIM_FOURTH_ID_BYTE, + [4 ... 7] = 0xFF, +}; + +module_param_array(id_bytes, byte, NULL, 0400); +module_param_named(first_id_byte, id_bytes[0], byte, 0400); +module_param_named(second_id_byte, id_bytes[1], byte, 0400); +module_param_named(third_id_byte, id_bytes[2], byte, 0400); +module_param_named(fourth_id_byte, id_bytes[3], byte, 0400); +module_param(access_delay, uint, 0400); +module_param(programm_delay, uint, 0400); +module_param(erase_delay, uint, 0400); +module_param(output_cycle, uint, 0400); +module_param(input_cycle, uint, 0400); +module_param(bus_width, uint, 0400); +module_param(do_delays, uint, 0400); +module_param(log, uint, 0400); +module_param(dbg, uint, 0400); +module_param_array(parts, ulong, &parts_num, 0400); +module_param(badblocks, charp, 0400); +module_param(weakblocks, charp, 0400); +module_param(weakpages, charp, 0400); +module_param(bitflips, uint, 0400); +module_param(gravepages, charp, 0400); +module_param(overridesize, uint, 0400); +module_param(cache_file, charp, 0400); +module_param(bbt, uint, 0400); +module_param(bch, uint, 0400); + +MODULE_PARM_DESC(id_bytes, "The ID bytes returned by NAND Flash 'read ID' command"); +MODULE_PARM_DESC(first_id_byte, "The first byte returned by NAND Flash 'read ID' command (manufacturer ID) (obsolete)"); +MODULE_PARM_DESC(second_id_byte, "The second byte returned by NAND Flash 'read ID' command (chip ID) (obsolete)"); +MODULE_PARM_DESC(third_id_byte, "The third byte returned by NAND Flash 'read ID' command (obsolete)"); +MODULE_PARM_DESC(fourth_id_byte, "The fourth byte returned by NAND Flash 'read ID' command (obsolete)"); +MODULE_PARM_DESC(access_delay, "Initial page access delay (microseconds)"); +MODULE_PARM_DESC(programm_delay, "Page programm delay (microseconds"); +MODULE_PARM_DESC(erase_delay, "Sector erase delay (milliseconds)"); +MODULE_PARM_DESC(output_cycle, "Word output (from flash) time (nanoseconds)"); +MODULE_PARM_DESC(input_cycle, "Word input (to flash) time (nanoseconds)"); +MODULE_PARM_DESC(bus_width, "Chip's bus width (8- or 16-bit)"); +MODULE_PARM_DESC(do_delays, "Simulate NAND delays using busy-waits if not zero"); +MODULE_PARM_DESC(log, "Perform logging if not zero"); +MODULE_PARM_DESC(dbg, "Output debug information if not zero"); +MODULE_PARM_DESC(parts, "Partition sizes (in erase blocks) separated by commas"); +/* Page and erase block positions for the following parameters are independent of any partitions */ +MODULE_PARM_DESC(badblocks, "Erase blocks that are initially marked bad, separated by commas"); +MODULE_PARM_DESC(weakblocks, "Weak erase blocks [: remaining erase cycles (defaults to 3)]" + " separated by commas e.g. 113:2 means eb 113" + " can be erased only twice before failing"); +MODULE_PARM_DESC(weakpages, "Weak pages [: maximum writes (defaults to 3)]" + " separated by commas e.g. 1401:2 means page 1401" + " can be written only twice before failing"); +MODULE_PARM_DESC(bitflips, "Maximum number of random bit flips per page (zero by default)"); +MODULE_PARM_DESC(gravepages, "Pages that lose data [: maximum reads (defaults to 3)]" + " separated by commas e.g. 1401:2 means page 1401" + " can be read only twice before failing"); +MODULE_PARM_DESC(overridesize, "Specifies the NAND Flash size overriding the ID bytes. " + "The size is specified in erase blocks and as the exponent of a power of two" + " e.g. 5 means a size of 32 erase blocks"); +MODULE_PARM_DESC(cache_file, "File to use to cache nand pages instead of memory"); +MODULE_PARM_DESC(bbt, "0 OOB, 1 BBT with marker in OOB, 2 BBT with marker in data area"); +MODULE_PARM_DESC(bch, "Enable BCH ecc and set how many bits should " + "be correctable in 512-byte blocks"); + +/* The largest possible page size */ +#define NS_LARGEST_PAGE_SIZE 4096 + +/* The prefix for simulator output */ +#define NS_OUTPUT_PREFIX "[nandsim]" + +/* Simulator's output macros (logging, debugging, warning, error) */ +#define NS_LOG(args...) \ + do { if (log) printk(KERN_DEBUG NS_OUTPUT_PREFIX " log: " args); } while(0) +#define NS_DBG(args...) \ + do { if (dbg) printk(KERN_DEBUG NS_OUTPUT_PREFIX " debug: " args); } while(0) +#define NS_WARN(args...) \ + do { printk(KERN_WARNING NS_OUTPUT_PREFIX " warning: " args); } while(0) +#define NS_ERR(args...) \ + do { printk(KERN_ERR NS_OUTPUT_PREFIX " error: " args); } while(0) +#define NS_INFO(args...) \ + do { printk(KERN_INFO NS_OUTPUT_PREFIX " " args); } while(0) + +/* Busy-wait delay macros (microseconds, milliseconds) */ +#define NS_UDELAY(us) \ + do { if (do_delays) udelay(us); } while(0) +#define NS_MDELAY(us) \ + do { if (do_delays) mdelay(us); } while(0) + +/* Is the nandsim structure initialized ? */ +#define NS_IS_INITIALIZED(ns) ((ns)->geom.totsz != 0) + +/* Good operation completion status */ +#define NS_STATUS_OK(ns) (NAND_STATUS_READY | (NAND_STATUS_WP * ((ns)->lines.wp == 0))) + +/* Operation failed completion status */ +#define NS_STATUS_FAILED(ns) (NAND_STATUS_FAIL | NS_STATUS_OK(ns)) + +/* Calculate the page offset in flash RAM image by (row, column) address */ +#define NS_RAW_OFFSET(ns) \ + (((ns)->regs.row * (ns)->geom.pgszoob) + (ns)->regs.column) + +/* Calculate the OOB offset in flash RAM image by (row, column) address */ +#define NS_RAW_OFFSET_OOB(ns) (NS_RAW_OFFSET(ns) + ns->geom.pgsz) + +/* After a command is input, the simulator goes to one of the following states */ +#define STATE_CMD_READ0 0x00000001 /* read data from the beginning of page */ +#define STATE_CMD_READ1 0x00000002 /* read data from the second half of page */ +#define STATE_CMD_READSTART 0x00000003 /* read data second command (large page devices) */ +#define STATE_CMD_PAGEPROG 0x00000004 /* start page program */ +#define STATE_CMD_READOOB 0x00000005 /* read OOB area */ +#define STATE_CMD_ERASE1 0x00000006 /* sector erase first command */ +#define STATE_CMD_STATUS 0x00000007 /* read status */ +#define STATE_CMD_SEQIN 0x00000009 /* sequential data input */ +#define STATE_CMD_READID 0x0000000A /* read ID */ +#define STATE_CMD_ERASE2 0x0000000B /* sector erase second command */ +#define STATE_CMD_RESET 0x0000000C /* reset */ +#define STATE_CMD_RNDOUT 0x0000000D /* random output command */ +#define STATE_CMD_RNDOUTSTART 0x0000000E /* random output start command */ +#define STATE_CMD_MASK 0x0000000F /* command states mask */ + +/* After an address is input, the simulator goes to one of these states */ +#define STATE_ADDR_PAGE 0x00000010 /* full (row, column) address is accepted */ +#define STATE_ADDR_SEC 0x00000020 /* sector address was accepted */ +#define STATE_ADDR_COLUMN 0x00000030 /* column address was accepted */ +#define STATE_ADDR_ZERO 0x00000040 /* one byte zero address was accepted */ +#define STATE_ADDR_MASK 0x00000070 /* address states mask */ + +/* During data input/output the simulator is in these states */ +#define STATE_DATAIN 0x00000100 /* waiting for data input */ +#define STATE_DATAIN_MASK 0x00000100 /* data input states mask */ + +#define STATE_DATAOUT 0x00001000 /* waiting for page data output */ +#define STATE_DATAOUT_ID 0x00002000 /* waiting for ID bytes output */ +#define STATE_DATAOUT_STATUS 0x00003000 /* waiting for status output */ +#define STATE_DATAOUT_MASK 0x00007000 /* data output states mask */ + +/* Previous operation is done, ready to accept new requests */ +#define STATE_READY 0x00000000 + +/* This state is used to mark that the next state isn't known yet */ +#define STATE_UNKNOWN 0x10000000 + +/* Simulator's actions bit masks */ +#define ACTION_CPY 0x00100000 /* copy page/OOB to the internal buffer */ +#define ACTION_PRGPAGE 0x00200000 /* program the internal buffer to flash */ +#define ACTION_SECERASE 0x00300000 /* erase sector */ +#define ACTION_ZEROOFF 0x00400000 /* don't add any offset to address */ +#define ACTION_HALFOFF 0x00500000 /* add to address half of page */ +#define ACTION_OOBOFF 0x00600000 /* add to address OOB offset */ +#define ACTION_MASK 0x00700000 /* action mask */ + +#define NS_OPER_NUM 13 /* Number of operations supported by the simulator */ +#define NS_OPER_STATES 6 /* Maximum number of states in operation */ + +#define OPT_ANY 0xFFFFFFFF /* any chip supports this operation */ +#define OPT_PAGE512 0x00000002 /* 512-byte page chips */ +#define OPT_PAGE2048 0x00000008 /* 2048-byte page chips */ +#define OPT_PAGE512_8BIT 0x00000040 /* 512-byte page chips with 8-bit bus width */ +#define OPT_PAGE4096 0x00000080 /* 4096-byte page chips */ +#define OPT_LARGEPAGE (OPT_PAGE2048 | OPT_PAGE4096) /* 2048 & 4096-byte page chips */ +#define OPT_SMALLPAGE (OPT_PAGE512) /* 512-byte page chips */ + +/* Remove action bits from state */ +#define NS_STATE(x) ((x) & ~ACTION_MASK) + +/* + * Maximum previous states which need to be saved. Currently saving is + * only needed for page program operation with preceded read command + * (which is only valid for 512-byte pages). + */ +#define NS_MAX_PREVSTATES 1 + +/* Maximum page cache pages needed to read or write a NAND page to the cache_file */ +#define NS_MAX_HELD_PAGES 16 + +/* + * A union to represent flash memory contents and flash buffer. + */ +union ns_mem { + u_char *byte; /* for byte access */ + uint16_t *word; /* for 16-bit word access */ +}; + +/* + * The structure which describes all the internal simulator data. + */ +struct nandsim { + struct mtd_partition partitions[CONFIG_NANDSIM_MAX_PARTS]; + unsigned int nbparts; + + uint busw; /* flash chip bus width (8 or 16) */ + u_char ids[8]; /* chip's ID bytes */ + uint32_t options; /* chip's characteristic bits */ + uint32_t state; /* current chip state */ + uint32_t nxstate; /* next expected state */ + + uint32_t *op; /* current operation, NULL operations isn't known yet */ + uint32_t pstates[NS_MAX_PREVSTATES]; /* previous states */ + uint16_t npstates; /* number of previous states saved */ + uint16_t stateidx; /* current state index */ + + /* The simulated NAND flash pages array */ + union ns_mem *pages; + + /* Slab allocator for nand pages */ + struct kmem_cache *nand_pages_slab; + + /* Internal buffer of page + OOB size bytes */ + union ns_mem buf; + + /* NAND flash "geometry" */ + struct { + uint64_t totsz; /* total flash size, bytes */ + uint32_t secsz; /* flash sector (erase block) size, bytes */ + uint pgsz; /* NAND flash page size, bytes */ + uint oobsz; /* page OOB area size, bytes */ + uint64_t totszoob; /* total flash size including OOB, bytes */ + uint pgszoob; /* page size including OOB , bytes*/ + uint secszoob; /* sector size including OOB, bytes */ + uint pgnum; /* total number of pages */ + uint pgsec; /* number of pages per sector */ + uint secshift; /* bits number in sector size */ + uint pgshift; /* bits number in page size */ + uint pgaddrbytes; /* bytes per page address */ + uint secaddrbytes; /* bytes per sector address */ + uint idbytes; /* the number ID bytes that this chip outputs */ + } geom; + + /* NAND flash internal registers */ + struct { + unsigned command; /* the command register */ + u_char status; /* the status register */ + uint row; /* the page number */ + uint column; /* the offset within page */ + uint count; /* internal counter */ + uint num; /* number of bytes which must be processed */ + uint off; /* fixed page offset */ + } regs; + + /* NAND flash lines state */ + struct { + int ce; /* chip Enable */ + int cle; /* command Latch Enable */ + int ale; /* address Latch Enable */ + int wp; /* write Protect */ + } lines; + + /* Fields needed when using a cache file */ + struct file *cfile; /* Open file */ + unsigned long *pages_written; /* Which pages have been written */ + void *file_buf; + struct page *held_pages[NS_MAX_HELD_PAGES]; + int held_cnt; +}; + +/* + * Operations array. To perform any operation the simulator must pass + * through the correspondent states chain. + */ +static struct nandsim_operations { + uint32_t reqopts; /* options which are required to perform the operation */ + uint32_t states[NS_OPER_STATES]; /* operation's states */ +} ops[NS_OPER_NUM] = { + /* Read page + OOB from the beginning */ + {OPT_SMALLPAGE, {STATE_CMD_READ0 | ACTION_ZEROOFF, STATE_ADDR_PAGE | ACTION_CPY, + STATE_DATAOUT, STATE_READY}}, + /* Read page + OOB from the second half */ + {OPT_PAGE512_8BIT, {STATE_CMD_READ1 | ACTION_HALFOFF, STATE_ADDR_PAGE | ACTION_CPY, + STATE_DATAOUT, STATE_READY}}, + /* Read OOB */ + {OPT_SMALLPAGE, {STATE_CMD_READOOB | ACTION_OOBOFF, STATE_ADDR_PAGE | ACTION_CPY, + STATE_DATAOUT, STATE_READY}}, + /* Program page starting from the beginning */ + {OPT_ANY, {STATE_CMD_SEQIN, STATE_ADDR_PAGE, STATE_DATAIN, + STATE_CMD_PAGEPROG | ACTION_PRGPAGE, STATE_READY}}, + /* Program page starting from the beginning */ + {OPT_SMALLPAGE, {STATE_CMD_READ0, STATE_CMD_SEQIN | ACTION_ZEROOFF, STATE_ADDR_PAGE, + STATE_DATAIN, STATE_CMD_PAGEPROG | ACTION_PRGPAGE, STATE_READY}}, + /* Program page starting from the second half */ + {OPT_PAGE512, {STATE_CMD_READ1, STATE_CMD_SEQIN | ACTION_HALFOFF, STATE_ADDR_PAGE, + STATE_DATAIN, STATE_CMD_PAGEPROG | ACTION_PRGPAGE, STATE_READY}}, + /* Program OOB */ + {OPT_SMALLPAGE, {STATE_CMD_READOOB, STATE_CMD_SEQIN | ACTION_OOBOFF, STATE_ADDR_PAGE, + STATE_DATAIN, STATE_CMD_PAGEPROG | ACTION_PRGPAGE, STATE_READY}}, + /* Erase sector */ + {OPT_ANY, {STATE_CMD_ERASE1, STATE_ADDR_SEC, STATE_CMD_ERASE2 | ACTION_SECERASE, STATE_READY}}, + /* Read status */ + {OPT_ANY, {STATE_CMD_STATUS, STATE_DATAOUT_STATUS, STATE_READY}}, + /* Read ID */ + {OPT_ANY, {STATE_CMD_READID, STATE_ADDR_ZERO, STATE_DATAOUT_ID, STATE_READY}}, + /* Large page devices read page */ + {OPT_LARGEPAGE, {STATE_CMD_READ0, STATE_ADDR_PAGE, STATE_CMD_READSTART | ACTION_CPY, + STATE_DATAOUT, STATE_READY}}, + /* Large page devices random page read */ + {OPT_LARGEPAGE, {STATE_CMD_RNDOUT, STATE_ADDR_COLUMN, STATE_CMD_RNDOUTSTART | ACTION_CPY, + STATE_DATAOUT, STATE_READY}}, +}; + +struct weak_block { + struct list_head list; + unsigned int erase_block_no; + unsigned int max_erases; + unsigned int erases_done; +}; + +static LIST_HEAD(weak_blocks); + +struct weak_page { + struct list_head list; + unsigned int page_no; + unsigned int max_writes; + unsigned int writes_done; +}; + +static LIST_HEAD(weak_pages); + +struct grave_page { + struct list_head list; + unsigned int page_no; + unsigned int max_reads; + unsigned int reads_done; +}; + +static LIST_HEAD(grave_pages); + +static unsigned long *erase_block_wear = NULL; +static unsigned int wear_eb_count = 0; +static unsigned long total_wear = 0; + +/* MTD structure for NAND controller */ +static struct mtd_info *nsmtd; + +static int nandsim_debugfs_show(struct seq_file *m, void *private) +{ + unsigned long wmin = -1, wmax = 0, avg; + unsigned long deciles[10], decile_max[10], tot = 0; + unsigned int i; + + /* Calc wear stats */ + for (i = 0; i < wear_eb_count; ++i) { + unsigned long wear = erase_block_wear[i]; + if (wear < wmin) + wmin = wear; + if (wear > wmax) + wmax = wear; + tot += wear; + } + + for (i = 0; i < 9; ++i) { + deciles[i] = 0; + decile_max[i] = (wmax * (i + 1) + 5) / 10; + } + deciles[9] = 0; + decile_max[9] = wmax; + for (i = 0; i < wear_eb_count; ++i) { + int d; + unsigned long wear = erase_block_wear[i]; + for (d = 0; d < 10; ++d) + if (wear <= decile_max[d]) { + deciles[d] += 1; + break; + } + } + avg = tot / wear_eb_count; + + /* Output wear report */ + seq_printf(m, "Total numbers of erases: %lu\n", tot); + seq_printf(m, "Number of erase blocks: %u\n", wear_eb_count); + seq_printf(m, "Average number of erases: %lu\n", avg); + seq_printf(m, "Maximum number of erases: %lu\n", wmax); + seq_printf(m, "Minimum number of erases: %lu\n", wmin); + for (i = 0; i < 10; ++i) { + unsigned long from = (i ? decile_max[i - 1] + 1 : 0); + if (from > decile_max[i]) + continue; + seq_printf(m, "Number of ebs with erase counts from %lu to %lu : %lu\n", + from, + decile_max[i], + deciles[i]); + } + + return 0; +} + +static int nandsim_debugfs_open(struct inode *inode, struct file *file) +{ + return single_open(file, nandsim_debugfs_show, inode->i_private); +} + +static const struct file_operations dfs_fops = { + .open = nandsim_debugfs_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + +/** + * nandsim_debugfs_create - initialize debugfs + * @dev: nandsim device description object + * + * This function creates all debugfs files for UBI device @ubi. Returns zero in + * case of success and a negative error code in case of failure. + */ +static int nandsim_debugfs_create(struct nandsim *dev) +{ + struct dentry *root = nsmtd->dbg.dfs_dir; + struct dentry *dent; + + /* + * Just skip debugfs initialization when the debugfs directory is + * missing. + */ + if (IS_ERR_OR_NULL(root)) { + if (IS_ENABLED(CONFIG_DEBUG_FS) && + !IS_ENABLED(CONFIG_MTD_PARTITIONED_MASTER)) + NS_WARN("CONFIG_MTD_PARTITIONED_MASTER must be enabled to expose debugfs stuff\n"); + return 0; + } + + dent = debugfs_create_file("nandsim_wear_report", S_IRUSR, + root, dev, &dfs_fops); + if (IS_ERR_OR_NULL(dent)) { + NS_ERR("cannot create \"nandsim_wear_report\" debugfs entry\n"); + return -1; + } + + return 0; +} + +/* + * Allocate array of page pointers, create slab allocation for an array + * and initialize the array by NULL pointers. + * + * RETURNS: 0 if success, -ENOMEM if memory alloc fails. + */ +static int __init alloc_device(struct nandsim *ns) +{ + struct file *cfile; + int i, err; + + if (cache_file) { + cfile = filp_open(cache_file, O_CREAT | O_RDWR | O_LARGEFILE, 0600); + if (IS_ERR(cfile)) + return PTR_ERR(cfile); + if (!(cfile->f_mode & FMODE_CAN_READ)) { + NS_ERR("alloc_device: cache file not readable\n"); + err = -EINVAL; + goto err_close; + } + if (!(cfile->f_mode & FMODE_CAN_WRITE)) { + NS_ERR("alloc_device: cache file not writeable\n"); + err = -EINVAL; + goto err_close; + } + ns->pages_written = vzalloc(BITS_TO_LONGS(ns->geom.pgnum) * + sizeof(unsigned long)); + if (!ns->pages_written) { + NS_ERR("alloc_device: unable to allocate pages written array\n"); + err = -ENOMEM; + goto err_close; + } + ns->file_buf = kmalloc(ns->geom.pgszoob, GFP_KERNEL); + if (!ns->file_buf) { + NS_ERR("alloc_device: unable to allocate file buf\n"); + err = -ENOMEM; + goto err_free; + } + ns->cfile = cfile; + return 0; + } + + ns->pages = vmalloc(ns->geom.pgnum * sizeof(union ns_mem)); + if (!ns->pages) { + NS_ERR("alloc_device: unable to allocate page array\n"); + return -ENOMEM; + } + for (i = 0; i < ns->geom.pgnum; i++) { + ns->pages[i].byte = NULL; + } + ns->nand_pages_slab = kmem_cache_create("nandsim", + ns->geom.pgszoob, 0, 0, NULL); + if (!ns->nand_pages_slab) { + NS_ERR("cache_create: unable to create kmem_cache\n"); + return -ENOMEM; + } + + return 0; + +err_free: + vfree(ns->pages_written); +err_close: + filp_close(cfile, NULL); + return err; +} + +/* + * Free any allocated pages, and free the array of page pointers. + */ +static void free_device(struct nandsim *ns) +{ + int i; + + if (ns->cfile) { + kfree(ns->file_buf); + vfree(ns->pages_written); + filp_close(ns->cfile, NULL); + return; + } + + if (ns->pages) { + for (i = 0; i < ns->geom.pgnum; i++) { + if (ns->pages[i].byte) + kmem_cache_free(ns->nand_pages_slab, + ns->pages[i].byte); + } + kmem_cache_destroy(ns->nand_pages_slab); + vfree(ns->pages); + } +} + +static char __init *get_partition_name(int i) +{ + return kasprintf(GFP_KERNEL, "NAND simulator partition %d", i); +} + +/* + * Initialize the nandsim structure. + * + * RETURNS: 0 if success, -ERRNO if failure. + */ +static int __init init_nandsim(struct mtd_info *mtd) +{ + struct nand_chip *chip = mtd_to_nand(mtd); + struct nandsim *ns = nand_get_controller_data(chip); + int i, ret = 0; + uint64_t remains; + uint64_t next_offset; + + if (NS_IS_INITIALIZED(ns)) { + NS_ERR("init_nandsim: nandsim is already initialized\n"); + return -EIO; + } + + /* Force mtd to not do delays */ + chip->chip_delay = 0; + + /* Initialize the NAND flash parameters */ + ns->busw = chip->options & NAND_BUSWIDTH_16 ? 16 : 8; + ns->geom.totsz = mtd->size; + ns->geom.pgsz = mtd->writesize; + ns->geom.oobsz = mtd->oobsize; + ns->geom.secsz = mtd->erasesize; + ns->geom.pgszoob = ns->geom.pgsz + ns->geom.oobsz; + ns->geom.pgnum = div_u64(ns->geom.totsz, ns->geom.pgsz); + ns->geom.totszoob = ns->geom.totsz + (uint64_t)ns->geom.pgnum * ns->geom.oobsz; + ns->geom.secshift = ffs(ns->geom.secsz) - 1; + ns->geom.pgshift = chip->page_shift; + ns->geom.pgsec = ns->geom.secsz / ns->geom.pgsz; + ns->geom.secszoob = ns->geom.secsz + ns->geom.oobsz * ns->geom.pgsec; + ns->options = 0; + + if (ns->geom.pgsz == 512) { + ns->options |= OPT_PAGE512; + if (ns->busw == 8) + ns->options |= OPT_PAGE512_8BIT; + } else if (ns->geom.pgsz == 2048) { + ns->options |= OPT_PAGE2048; + } else if (ns->geom.pgsz == 4096) { + ns->options |= OPT_PAGE4096; + } else { + NS_ERR("init_nandsim: unknown page size %u\n", ns->geom.pgsz); + return -EIO; + } + + if (ns->options & OPT_SMALLPAGE) { + if (ns->geom.totsz <= (32 << 20)) { + ns->geom.pgaddrbytes = 3; + ns->geom.secaddrbytes = 2; + } else { + ns->geom.pgaddrbytes = 4; + ns->geom.secaddrbytes = 3; + } + } else { + if (ns->geom.totsz <= (128 << 20)) { + ns->geom.pgaddrbytes = 4; + ns->geom.secaddrbytes = 2; + } else { + ns->geom.pgaddrbytes = 5; + ns->geom.secaddrbytes = 3; + } + } + + /* Fill the partition_info structure */ + if (parts_num > ARRAY_SIZE(ns->partitions)) { + NS_ERR("too many partitions.\n"); + return -EINVAL; + } + remains = ns->geom.totsz; + next_offset = 0; + for (i = 0; i < parts_num; ++i) { + uint64_t part_sz = (uint64_t)parts[i] * ns->geom.secsz; + + if (!part_sz || part_sz > remains) { + NS_ERR("bad partition size.\n"); + return -EINVAL; + } + ns->partitions[i].name = get_partition_name(i); + if (!ns->partitions[i].name) { + NS_ERR("unable to allocate memory.\n"); + return -ENOMEM; + } + ns->partitions[i].offset = next_offset; + ns->partitions[i].size = part_sz; + next_offset += ns->partitions[i].size; + remains -= ns->partitions[i].size; + } + ns->nbparts = parts_num; + if (remains) { + if (parts_num + 1 > ARRAY_SIZE(ns->partitions)) { + NS_ERR("too many partitions.\n"); + return -EINVAL; + } + ns->partitions[i].name = get_partition_name(i); + if (!ns->partitions[i].name) { + NS_ERR("unable to allocate memory.\n"); + return -ENOMEM; + } + ns->partitions[i].offset = next_offset; + ns->partitions[i].size = remains; + ns->nbparts += 1; + } + + if (ns->busw == 16) + NS_WARN("16-bit flashes support wasn't tested\n"); + + printk("flash size: %llu MiB\n", + (unsigned long long)ns->geom.totsz >> 20); + printk("page size: %u bytes\n", ns->geom.pgsz); + printk("OOB area size: %u bytes\n", ns->geom.oobsz); + printk("sector size: %u KiB\n", ns->geom.secsz >> 10); + printk("pages number: %u\n", ns->geom.pgnum); + printk("pages per sector: %u\n", ns->geom.pgsec); + printk("bus width: %u\n", ns->busw); + printk("bits in sector size: %u\n", ns->geom.secshift); + printk("bits in page size: %u\n", ns->geom.pgshift); + printk("bits in OOB size: %u\n", ffs(ns->geom.oobsz) - 1); + printk("flash size with OOB: %llu KiB\n", + (unsigned long long)ns->geom.totszoob >> 10); + printk("page address bytes: %u\n", ns->geom.pgaddrbytes); + printk("sector address bytes: %u\n", ns->geom.secaddrbytes); + printk("options: %#x\n", ns->options); + + if ((ret = alloc_device(ns)) != 0) + return ret; + + /* Allocate / initialize the internal buffer */ + ns->buf.byte = kmalloc(ns->geom.pgszoob, GFP_KERNEL); + if (!ns->buf.byte) { + NS_ERR("init_nandsim: unable to allocate %u bytes for the internal buffer\n", + ns->geom.pgszoob); + return -ENOMEM; + } + memset(ns->buf.byte, 0xFF, ns->geom.pgszoob); + + return 0; +} + +/* + * Free the nandsim structure. + */ +static void free_nandsim(struct nandsim *ns) +{ + kfree(ns->buf.byte); + free_device(ns); + + return; +} + +static int parse_badblocks(struct nandsim *ns, struct mtd_info *mtd) +{ + char *w; + int zero_ok; + unsigned int erase_block_no; + loff_t offset; + + if (!badblocks) + return 0; + w = badblocks; + do { + zero_ok = (*w == '0' ? 1 : 0); + erase_block_no = simple_strtoul(w, &w, 0); + if (!zero_ok && !erase_block_no) { + NS_ERR("invalid badblocks.\n"); + return -EINVAL; + } + offset = (loff_t)erase_block_no * ns->geom.secsz; + if (mtd_block_markbad(mtd, offset)) { + NS_ERR("invalid badblocks.\n"); + return -EINVAL; + } + if (*w == ',') + w += 1; + } while (*w); + return 0; +} + +static int parse_weakblocks(void) +{ + char *w; + int zero_ok; + unsigned int erase_block_no; + unsigned int max_erases; + struct weak_block *wb; + + if (!weakblocks) + return 0; + w = weakblocks; + do { + zero_ok = (*w == '0' ? 1 : 0); + erase_block_no = simple_strtoul(w, &w, 0); + if (!zero_ok && !erase_block_no) { + NS_ERR("invalid weakblocks.\n"); + return -EINVAL; + } + max_erases = 3; + if (*w == ':') { + w += 1; + max_erases = simple_strtoul(w, &w, 0); + } + if (*w == ',') + w += 1; + wb = kzalloc(sizeof(*wb), GFP_KERNEL); + if (!wb) { + NS_ERR("unable to allocate memory.\n"); + return -ENOMEM; + } + wb->erase_block_no = erase_block_no; + wb->max_erases = max_erases; + list_add(&wb->list, &weak_blocks); + } while (*w); + return 0; +} + +static int erase_error(unsigned int erase_block_no) +{ + struct weak_block *wb; + + list_for_each_entry(wb, &weak_blocks, list) + if (wb->erase_block_no == erase_block_no) { + if (wb->erases_done >= wb->max_erases) + return 1; + wb->erases_done += 1; + return 0; + } + return 0; +} + +static int parse_weakpages(void) +{ + char *w; + int zero_ok; + unsigned int page_no; + unsigned int max_writes; + struct weak_page *wp; + + if (!weakpages) + return 0; + w = weakpages; + do { + zero_ok = (*w == '0' ? 1 : 0); + page_no = simple_strtoul(w, &w, 0); + if (!zero_ok && !page_no) { + NS_ERR("invalid weakpages.\n"); + return -EINVAL; + } + max_writes = 3; + if (*w == ':') { + w += 1; + max_writes = simple_strtoul(w, &w, 0); + } + if (*w == ',') + w += 1; + wp = kzalloc(sizeof(*wp), GFP_KERNEL); + if (!wp) { + NS_ERR("unable to allocate memory.\n"); + return -ENOMEM; + } + wp->page_no = page_no; + wp->max_writes = max_writes; + list_add(&wp->list, &weak_pages); + } while (*w); + return 0; +} + +static int write_error(unsigned int page_no) +{ + struct weak_page *wp; + + list_for_each_entry(wp, &weak_pages, list) + if (wp->page_no == page_no) { + if (wp->writes_done >= wp->max_writes) + return 1; + wp->writes_done += 1; + return 0; + } + return 0; +} + +static int parse_gravepages(void) +{ + char *g; + int zero_ok; + unsigned int page_no; + unsigned int max_reads; + struct grave_page *gp; + + if (!gravepages) + return 0; + g = gravepages; + do { + zero_ok = (*g == '0' ? 1 : 0); + page_no = simple_strtoul(g, &g, 0); + if (!zero_ok && !page_no) { + NS_ERR("invalid gravepagess.\n"); + return -EINVAL; + } + max_reads = 3; + if (*g == ':') { + g += 1; + max_reads = simple_strtoul(g, &g, 0); + } + if (*g == ',') + g += 1; + gp = kzalloc(sizeof(*gp), GFP_KERNEL); + if (!gp) { + NS_ERR("unable to allocate memory.\n"); + return -ENOMEM; + } + gp->page_no = page_no; + gp->max_reads = max_reads; + list_add(&gp->list, &grave_pages); + } while (*g); + return 0; +} + +static int read_error(unsigned int page_no) +{ + struct grave_page *gp; + + list_for_each_entry(gp, &grave_pages, list) + if (gp->page_no == page_no) { + if (gp->reads_done >= gp->max_reads) + return 1; + gp->reads_done += 1; + return 0; + } + return 0; +} + +static void free_lists(void) +{ + struct list_head *pos, *n; + list_for_each_safe(pos, n, &weak_blocks) { + list_del(pos); + kfree(list_entry(pos, struct weak_block, list)); + } + list_for_each_safe(pos, n, &weak_pages) { + list_del(pos); + kfree(list_entry(pos, struct weak_page, list)); + } + list_for_each_safe(pos, n, &grave_pages) { + list_del(pos); + kfree(list_entry(pos, struct grave_page, list)); + } + kfree(erase_block_wear); +} + +static int setup_wear_reporting(struct mtd_info *mtd) +{ + size_t mem; + + wear_eb_count = div_u64(mtd->size, mtd->erasesize); + mem = wear_eb_count * sizeof(unsigned long); + if (mem / sizeof(unsigned long) != wear_eb_count) { + NS_ERR("Too many erase blocks for wear reporting\n"); + return -ENOMEM; + } + erase_block_wear = kzalloc(mem, GFP_KERNEL); + if (!erase_block_wear) { + NS_ERR("Too many erase blocks for wear reporting\n"); + return -ENOMEM; + } + return 0; +} + +static void update_wear(unsigned int erase_block_no) +{ + if (!erase_block_wear) + return; + total_wear += 1; + /* + * TODO: Notify this through a debugfs entry, + * instead of showing an error message. + */ + if (total_wear == 0) + NS_ERR("Erase counter total overflow\n"); + erase_block_wear[erase_block_no] += 1; + if (erase_block_wear[erase_block_no] == 0) + NS_ERR("Erase counter overflow for erase block %u\n", erase_block_no); +} + +/* + * Returns the string representation of 'state' state. + */ +static char *get_state_name(uint32_t state) +{ + switch (NS_STATE(state)) { + case STATE_CMD_READ0: + return "STATE_CMD_READ0"; + case STATE_CMD_READ1: + return "STATE_CMD_READ1"; + case STATE_CMD_PAGEPROG: + return "STATE_CMD_PAGEPROG"; + case STATE_CMD_READOOB: + return "STATE_CMD_READOOB"; + case STATE_CMD_READSTART: + return "STATE_CMD_READSTART"; + case STATE_CMD_ERASE1: + return "STATE_CMD_ERASE1"; + case STATE_CMD_STATUS: + return "STATE_CMD_STATUS"; + case STATE_CMD_SEQIN: + return "STATE_CMD_SEQIN"; + case STATE_CMD_READID: + return "STATE_CMD_READID"; + case STATE_CMD_ERASE2: + return "STATE_CMD_ERASE2"; + case STATE_CMD_RESET: + return "STATE_CMD_RESET"; + case STATE_CMD_RNDOUT: + return "STATE_CMD_RNDOUT"; + case STATE_CMD_RNDOUTSTART: + return "STATE_CMD_RNDOUTSTART"; + case STATE_ADDR_PAGE: + return "STATE_ADDR_PAGE"; + case STATE_ADDR_SEC: + return "STATE_ADDR_SEC"; + case STATE_ADDR_ZERO: + return "STATE_ADDR_ZERO"; + case STATE_ADDR_COLUMN: + return "STATE_ADDR_COLUMN"; + case STATE_DATAIN: + return "STATE_DATAIN"; + case STATE_DATAOUT: + return "STATE_DATAOUT"; + case STATE_DATAOUT_ID: + return "STATE_DATAOUT_ID"; + case STATE_DATAOUT_STATUS: + return "STATE_DATAOUT_STATUS"; + case STATE_READY: + return "STATE_READY"; + case STATE_UNKNOWN: + return "STATE_UNKNOWN"; + } + + NS_ERR("get_state_name: unknown state, BUG\n"); + return NULL; +} + +/* + * Check if command is valid. + * + * RETURNS: 1 if wrong command, 0 if right. + */ +static int check_command(int cmd) +{ + switch (cmd) { + + case NAND_CMD_READ0: + case NAND_CMD_READ1: + case NAND_CMD_READSTART: + case NAND_CMD_PAGEPROG: + case NAND_CMD_READOOB: + case NAND_CMD_ERASE1: + case NAND_CMD_STATUS: + case NAND_CMD_SEQIN: + case NAND_CMD_READID: + case NAND_CMD_ERASE2: + case NAND_CMD_RESET: + case NAND_CMD_RNDOUT: + case NAND_CMD_RNDOUTSTART: + return 0; + + default: + return 1; + } +} + +/* + * Returns state after command is accepted by command number. + */ +static uint32_t get_state_by_command(unsigned command) +{ + switch (command) { + case NAND_CMD_READ0: + return STATE_CMD_READ0; + case NAND_CMD_READ1: + return STATE_CMD_READ1; + case NAND_CMD_PAGEPROG: + return STATE_CMD_PAGEPROG; + case NAND_CMD_READSTART: + return STATE_CMD_READSTART; + case NAND_CMD_READOOB: + return STATE_CMD_READOOB; + case NAND_CMD_ERASE1: + return STATE_CMD_ERASE1; + case NAND_CMD_STATUS: + return STATE_CMD_STATUS; + case NAND_CMD_SEQIN: + return STATE_CMD_SEQIN; + case NAND_CMD_READID: + return STATE_CMD_READID; + case NAND_CMD_ERASE2: + return STATE_CMD_ERASE2; + case NAND_CMD_RESET: + return STATE_CMD_RESET; + case NAND_CMD_RNDOUT: + return STATE_CMD_RNDOUT; + case NAND_CMD_RNDOUTSTART: + return STATE_CMD_RNDOUTSTART; + } + + NS_ERR("get_state_by_command: unknown command, BUG\n"); + return 0; +} + +/* + * Move an address byte to the correspondent internal register. + */ +static inline void accept_addr_byte(struct nandsim *ns, u_char bt) +{ + uint byte = (uint)bt; + + if (ns->regs.count < (ns->geom.pgaddrbytes - ns->geom.secaddrbytes)) + ns->regs.column |= (byte << 8 * ns->regs.count); + else { + ns->regs.row |= (byte << 8 * (ns->regs.count - + ns->geom.pgaddrbytes + + ns->geom.secaddrbytes)); + } + + return; +} + +/* + * Switch to STATE_READY state. + */ +static inline void switch_to_ready_state(struct nandsim *ns, u_char status) +{ + NS_DBG("switch_to_ready_state: switch to %s state\n", get_state_name(STATE_READY)); + + ns->state = STATE_READY; + ns->nxstate = STATE_UNKNOWN; + ns->op = NULL; + ns->npstates = 0; + ns->stateidx = 0; + ns->regs.num = 0; + ns->regs.count = 0; + ns->regs.off = 0; + ns->regs.row = 0; + ns->regs.column = 0; + ns->regs.status = status; +} + +/* + * If the operation isn't known yet, try to find it in the global array + * of supported operations. + * + * Operation can be unknown because of the following. + * 1. New command was accepted and this is the first call to find the + * correspondent states chain. In this case ns->npstates = 0; + * 2. There are several operations which begin with the same command(s) + * (for example program from the second half and read from the + * second half operations both begin with the READ1 command). In this + * case the ns->pstates[] array contains previous states. + * + * Thus, the function tries to find operation containing the following + * states (if the 'flag' parameter is 0): + * ns->pstates[0], ... ns->pstates[ns->npstates], ns->state + * + * If (one and only one) matching operation is found, it is accepted ( + * ns->ops, ns->state, ns->nxstate are initialized, ns->npstate is + * zeroed). + * + * If there are several matches, the current state is pushed to the + * ns->pstates. + * + * The operation can be unknown only while commands are input to the chip. + * As soon as address command is accepted, the operation must be known. + * In such situation the function is called with 'flag' != 0, and the + * operation is searched using the following pattern: + * ns->pstates[0], ... ns->pstates[ns->npstates], <address input> + * + * It is supposed that this pattern must either match one operation or + * none. There can't be ambiguity in that case. + * + * If no matches found, the function does the following: + * 1. if there are saved states present, try to ignore them and search + * again only using the last command. If nothing was found, switch + * to the STATE_READY state. + * 2. if there are no saved states, switch to the STATE_READY state. + * + * RETURNS: -2 - no matched operations found. + * -1 - several matches. + * 0 - operation is found. + */ +static int find_operation(struct nandsim *ns, uint32_t flag) +{ + int opsfound = 0; + int i, j, idx = 0; + + for (i = 0; i < NS_OPER_NUM; i++) { + + int found = 1; + + if (!(ns->options & ops[i].reqopts)) + /* Ignore operations we can't perform */ + continue; + + if (flag) { + if (!(ops[i].states[ns->npstates] & STATE_ADDR_MASK)) + continue; + } else { + if (NS_STATE(ns->state) != NS_STATE(ops[i].states[ns->npstates])) + continue; + } + + for (j = 0; j < ns->npstates; j++) + if (NS_STATE(ops[i].states[j]) != NS_STATE(ns->pstates[j]) + && (ns->options & ops[idx].reqopts)) { + found = 0; + break; + } + + if (found) { + idx = i; + opsfound += 1; + } + } + + if (opsfound == 1) { + /* Exact match */ + ns->op = &ops[idx].states[0]; + if (flag) { + /* + * In this case the find_operation function was + * called when address has just began input. But it isn't + * yet fully input and the current state must + * not be one of STATE_ADDR_*, but the STATE_ADDR_* + * state must be the next state (ns->nxstate). + */ + ns->stateidx = ns->npstates - 1; + } else { + ns->stateidx = ns->npstates; + } + ns->npstates = 0; + ns->state = ns->op[ns->stateidx]; + ns->nxstate = ns->op[ns->stateidx + 1]; + NS_DBG("find_operation: operation found, index: %d, state: %s, nxstate %s\n", + idx, get_state_name(ns->state), get_state_name(ns->nxstate)); + return 0; + } + + if (opsfound == 0) { + /* Nothing was found. Try to ignore previous commands (if any) and search again */ + if (ns->npstates != 0) { + NS_DBG("find_operation: no operation found, try again with state %s\n", + get_state_name(ns->state)); + ns->npstates = 0; + return find_operation(ns, 0); + + } + NS_DBG("find_operation: no operations found\n"); + switch_to_ready_state(ns, NS_STATUS_FAILED(ns)); + return -2; + } + + if (flag) { + /* This shouldn't happen */ + NS_DBG("find_operation: BUG, operation must be known if address is input\n"); + return -2; + } + + NS_DBG("find_operation: there is still ambiguity\n"); + + ns->pstates[ns->npstates++] = ns->state; + + return -1; +} + +static void put_pages(struct nandsim *ns) +{ + int i; + + for (i = 0; i < ns->held_cnt; i++) + put_page(ns->held_pages[i]); +} + +/* Get page cache pages in advance to provide NOFS memory allocation */ +static int get_pages(struct nandsim *ns, struct file *file, size_t count, loff_t pos) +{ + pgoff_t index, start_index, end_index; + struct page *page; + struct address_space *mapping = file->f_mapping; + + start_index = pos >> PAGE_SHIFT; + end_index = (pos + count - 1) >> PAGE_SHIFT; + if (end_index - start_index + 1 > NS_MAX_HELD_PAGES) + return -EINVAL; + ns->held_cnt = 0; + for (index = start_index; index <= end_index; index++) { + page = find_get_page(mapping, index); + if (page == NULL) { + page = find_or_create_page(mapping, index, GFP_NOFS); + if (page == NULL) { + write_inode_now(mapping->host, 1); + page = find_or_create_page(mapping, index, GFP_NOFS); + } + if (page == NULL) { + put_pages(ns); + return -ENOMEM; + } + unlock_page(page); + } + ns->held_pages[ns->held_cnt++] = page; + } + return 0; +} + +static ssize_t read_file(struct nandsim *ns, struct file *file, void *buf, size_t count, loff_t pos) +{ + ssize_t tx; + int err; + unsigned int noreclaim_flag; + + err = get_pages(ns, file, count, pos); + if (err) + return err; + noreclaim_flag = memalloc_noreclaim_save(); + tx = kernel_read(file, buf, count, &pos); + memalloc_noreclaim_restore(noreclaim_flag); + put_pages(ns); + return tx; +} + +static ssize_t write_file(struct nandsim *ns, struct file *file, void *buf, size_t count, loff_t pos) +{ + ssize_t tx; + int err; + unsigned int noreclaim_flag; + + err = get_pages(ns, file, count, pos); + if (err) + return err; + noreclaim_flag = memalloc_noreclaim_save(); + tx = kernel_write(file, buf, count, &pos); + memalloc_noreclaim_restore(noreclaim_flag); + put_pages(ns); + return tx; +} + +/* + * Returns a pointer to the current page. + */ +static inline union ns_mem *NS_GET_PAGE(struct nandsim *ns) +{ + return &(ns->pages[ns->regs.row]); +} + +/* + * Retuns a pointer to the current byte, within the current page. + */ +static inline u_char *NS_PAGE_BYTE_OFF(struct nandsim *ns) +{ + return NS_GET_PAGE(ns)->byte + ns->regs.column + ns->regs.off; +} + +static int do_read_error(struct nandsim *ns, int num) +{ + unsigned int page_no = ns->regs.row; + + if (read_error(page_no)) { + prandom_bytes(ns->buf.byte, num); + NS_WARN("simulating read error in page %u\n", page_no); + return 1; + } + return 0; +} + +static void do_bit_flips(struct nandsim *ns, int num) +{ + if (bitflips && prandom_u32() < (1 << 22)) { + int flips = 1; + if (bitflips > 1) + flips = (prandom_u32() % (int) bitflips) + 1; + while (flips--) { + int pos = prandom_u32() % (num * 8); + ns->buf.byte[pos / 8] ^= (1 << (pos % 8)); + NS_WARN("read_page: flipping bit %d in page %d " + "reading from %d ecc: corrected=%u failed=%u\n", + pos, ns->regs.row, ns->regs.column + ns->regs.off, + nsmtd->ecc_stats.corrected, nsmtd->ecc_stats.failed); + } + } +} + +/* + * Fill the NAND buffer with data read from the specified page. + */ +static void read_page(struct nandsim *ns, int num) +{ + union ns_mem *mypage; + + if (ns->cfile) { + if (!test_bit(ns->regs.row, ns->pages_written)) { + NS_DBG("read_page: page %d not written\n", ns->regs.row); + memset(ns->buf.byte, 0xFF, num); + } else { + loff_t pos; + ssize_t tx; + + NS_DBG("read_page: page %d written, reading from %d\n", + ns->regs.row, ns->regs.column + ns->regs.off); + if (do_read_error(ns, num)) + return; + pos = (loff_t)NS_RAW_OFFSET(ns) + ns->regs.off; + tx = read_file(ns, ns->cfile, ns->buf.byte, num, pos); + if (tx != num) { + NS_ERR("read_page: read error for page %d ret %ld\n", ns->regs.row, (long)tx); + return; + } + do_bit_flips(ns, num); + } + return; + } + + mypage = NS_GET_PAGE(ns); + if (mypage->byte == NULL) { + NS_DBG("read_page: page %d not allocated\n", ns->regs.row); + memset(ns->buf.byte, 0xFF, num); + } else { + NS_DBG("read_page: page %d allocated, reading from %d\n", + ns->regs.row, ns->regs.column + ns->regs.off); + if (do_read_error(ns, num)) + return; + memcpy(ns->buf.byte, NS_PAGE_BYTE_OFF(ns), num); + do_bit_flips(ns, num); + } +} + +/* + * Erase all pages in the specified sector. + */ +static void erase_sector(struct nandsim *ns) +{ + union ns_mem *mypage; + int i; + + if (ns->cfile) { + for (i = 0; i < ns->geom.pgsec; i++) + if (__test_and_clear_bit(ns->regs.row + i, + ns->pages_written)) { + NS_DBG("erase_sector: freeing page %d\n", ns->regs.row + i); + } + return; + } + + mypage = NS_GET_PAGE(ns); + for (i = 0; i < ns->geom.pgsec; i++) { + if (mypage->byte != NULL) { + NS_DBG("erase_sector: freeing page %d\n", ns->regs.row+i); + kmem_cache_free(ns->nand_pages_slab, mypage->byte); + mypage->byte = NULL; + } + mypage++; + } +} + +/* + * Program the specified page with the contents from the NAND buffer. + */ +static int prog_page(struct nandsim *ns, int num) +{ + int i; + union ns_mem *mypage; + u_char *pg_off; + + if (ns->cfile) { + loff_t off; + ssize_t tx; + int all; + + NS_DBG("prog_page: writing page %d\n", ns->regs.row); + pg_off = ns->file_buf + ns->regs.column + ns->regs.off; + off = (loff_t)NS_RAW_OFFSET(ns) + ns->regs.off; + if (!test_bit(ns->regs.row, ns->pages_written)) { + all = 1; + memset(ns->file_buf, 0xff, ns->geom.pgszoob); + } else { + all = 0; + tx = read_file(ns, ns->cfile, pg_off, num, off); + if (tx != num) { + NS_ERR("prog_page: read error for page %d ret %ld\n", ns->regs.row, (long)tx); + return -1; + } + } + for (i = 0; i < num; i++) + pg_off[i] &= ns->buf.byte[i]; + if (all) { + loff_t pos = (loff_t)ns->regs.row * ns->geom.pgszoob; + tx = write_file(ns, ns->cfile, ns->file_buf, ns->geom.pgszoob, pos); + if (tx != ns->geom.pgszoob) { + NS_ERR("prog_page: write error for page %d ret %ld\n", ns->regs.row, (long)tx); + return -1; + } + __set_bit(ns->regs.row, ns->pages_written); + } else { + tx = write_file(ns, ns->cfile, pg_off, num, off); + if (tx != num) { + NS_ERR("prog_page: write error for page %d ret %ld\n", ns->regs.row, (long)tx); + return -1; + } + } + return 0; + } + + mypage = NS_GET_PAGE(ns); + if (mypage->byte == NULL) { + NS_DBG("prog_page: allocating page %d\n", ns->regs.row); + /* + * We allocate memory with GFP_NOFS because a flash FS may + * utilize this. If it is holding an FS lock, then gets here, + * then kernel memory alloc runs writeback which goes to the FS + * again and deadlocks. This was seen in practice. + */ + mypage->byte = kmem_cache_alloc(ns->nand_pages_slab, GFP_NOFS); + if (mypage->byte == NULL) { + NS_ERR("prog_page: error allocating memory for page %d\n", ns->regs.row); + return -1; + } + memset(mypage->byte, 0xFF, ns->geom.pgszoob); + } + + pg_off = NS_PAGE_BYTE_OFF(ns); + for (i = 0; i < num; i++) + pg_off[i] &= ns->buf.byte[i]; + + return 0; +} + +/* + * If state has any action bit, perform this action. + * + * RETURNS: 0 if success, -1 if error. + */ +static int do_state_action(struct nandsim *ns, uint32_t action) +{ + int num; + int busdiv = ns->busw == 8 ? 1 : 2; + unsigned int erase_block_no, page_no; + + action &= ACTION_MASK; + + /* Check that page address input is correct */ + if (action != ACTION_SECERASE && ns->regs.row >= ns->geom.pgnum) { + NS_WARN("do_state_action: wrong page number (%#x)\n", ns->regs.row); + return -1; + } + + switch (action) { + + case ACTION_CPY: + /* + * Copy page data to the internal buffer. + */ + + /* Column shouldn't be very large */ + if (ns->regs.column >= (ns->geom.pgszoob - ns->regs.off)) { + NS_ERR("do_state_action: column number is too large\n"); + break; + } + num = ns->geom.pgszoob - ns->regs.off - ns->regs.column; + read_page(ns, num); + + NS_DBG("do_state_action: (ACTION_CPY:) copy %d bytes to int buf, raw offset %d\n", + num, NS_RAW_OFFSET(ns) + ns->regs.off); + + if (ns->regs.off == 0) + NS_LOG("read page %d\n", ns->regs.row); + else if (ns->regs.off < ns->geom.pgsz) + NS_LOG("read page %d (second half)\n", ns->regs.row); + else + NS_LOG("read OOB of page %d\n", ns->regs.row); + + NS_UDELAY(access_delay); + NS_UDELAY(input_cycle * ns->geom.pgsz / 1000 / busdiv); + + break; + + case ACTION_SECERASE: + /* + * Erase sector. + */ + + if (ns->lines.wp) { + NS_ERR("do_state_action: device is write-protected, ignore sector erase\n"); + return -1; + } + + if (ns->regs.row >= ns->geom.pgnum - ns->geom.pgsec + || (ns->regs.row & ~(ns->geom.secsz - 1))) { + NS_ERR("do_state_action: wrong sector address (%#x)\n", ns->regs.row); + return -1; + } + + ns->regs.row = (ns->regs.row << + 8 * (ns->geom.pgaddrbytes - ns->geom.secaddrbytes)) | ns->regs.column; + ns->regs.column = 0; + + erase_block_no = ns->regs.row >> (ns->geom.secshift - ns->geom.pgshift); + + NS_DBG("do_state_action: erase sector at address %#x, off = %d\n", + ns->regs.row, NS_RAW_OFFSET(ns)); + NS_LOG("erase sector %u\n", erase_block_no); + + erase_sector(ns); + + NS_MDELAY(erase_delay); + + if (erase_block_wear) + update_wear(erase_block_no); + + if (erase_error(erase_block_no)) { + NS_WARN("simulating erase failure in erase block %u\n", erase_block_no); + return -1; + } + + break; + + case ACTION_PRGPAGE: + /* + * Program page - move internal buffer data to the page. + */ + + if (ns->lines.wp) { + NS_WARN("do_state_action: device is write-protected, programm\n"); + return -1; + } + + num = ns->geom.pgszoob - ns->regs.off - ns->regs.column; + if (num != ns->regs.count) { + NS_ERR("do_state_action: too few bytes were input (%d instead of %d)\n", + ns->regs.count, num); + return -1; + } + + if (prog_page(ns, num) == -1) + return -1; + + page_no = ns->regs.row; + + NS_DBG("do_state_action: copy %d bytes from int buf to (%#x, %#x), raw off = %d\n", + num, ns->regs.row, ns->regs.column, NS_RAW_OFFSET(ns) + ns->regs.off); + NS_LOG("programm page %d\n", ns->regs.row); + + NS_UDELAY(programm_delay); + NS_UDELAY(output_cycle * ns->geom.pgsz / 1000 / busdiv); + + if (write_error(page_no)) { + NS_WARN("simulating write failure in page %u\n", page_no); + return -1; + } + + break; + + case ACTION_ZEROOFF: + NS_DBG("do_state_action: set internal offset to 0\n"); + ns->regs.off = 0; + break; + + case ACTION_HALFOFF: + if (!(ns->options & OPT_PAGE512_8BIT)) { + NS_ERR("do_state_action: BUG! can't skip half of page for non-512" + "byte page size 8x chips\n"); + return -1; + } + NS_DBG("do_state_action: set internal offset to %d\n", ns->geom.pgsz/2); + ns->regs.off = ns->geom.pgsz/2; + break; + + case ACTION_OOBOFF: + NS_DBG("do_state_action: set internal offset to %d\n", ns->geom.pgsz); + ns->regs.off = ns->geom.pgsz; + break; + + default: + NS_DBG("do_state_action: BUG! unknown action\n"); + } + + return 0; +} + +/* + * Switch simulator's state. + */ +static void switch_state(struct nandsim *ns) +{ + if (ns->op) { + /* + * The current operation have already been identified. + * Just follow the states chain. + */ + + ns->stateidx += 1; + ns->state = ns->nxstate; + ns->nxstate = ns->op[ns->stateidx + 1]; + + NS_DBG("switch_state: operation is known, switch to the next state, " + "state: %s, nxstate: %s\n", + get_state_name(ns->state), get_state_name(ns->nxstate)); + + /* See, whether we need to do some action */ + if ((ns->state & ACTION_MASK) && do_state_action(ns, ns->state) < 0) { + switch_to_ready_state(ns, NS_STATUS_FAILED(ns)); + return; + } + + } else { + /* + * We don't yet know which operation we perform. + * Try to identify it. + */ + + /* + * The only event causing the switch_state function to + * be called with yet unknown operation is new command. + */ + ns->state = get_state_by_command(ns->regs.command); + + NS_DBG("switch_state: operation is unknown, try to find it\n"); + + if (find_operation(ns, 0) != 0) + return; + + if ((ns->state & ACTION_MASK) && do_state_action(ns, ns->state) < 0) { + switch_to_ready_state(ns, NS_STATUS_FAILED(ns)); + return; + } + } + + /* For 16x devices column means the page offset in words */ + if ((ns->nxstate & STATE_ADDR_MASK) && ns->busw == 16) { + NS_DBG("switch_state: double the column number for 16x device\n"); + ns->regs.column <<= 1; + } + + if (NS_STATE(ns->nxstate) == STATE_READY) { + /* + * The current state is the last. Return to STATE_READY + */ + + u_char status = NS_STATUS_OK(ns); + + /* In case of data states, see if all bytes were input/output */ + if ((ns->state & (STATE_DATAIN_MASK | STATE_DATAOUT_MASK)) + && ns->regs.count != ns->regs.num) { + NS_WARN("switch_state: not all bytes were processed, %d left\n", + ns->regs.num - ns->regs.count); + status = NS_STATUS_FAILED(ns); + } + + NS_DBG("switch_state: operation complete, switch to STATE_READY state\n"); + + switch_to_ready_state(ns, status); + + return; + } else if (ns->nxstate & (STATE_DATAIN_MASK | STATE_DATAOUT_MASK)) { + /* + * If the next state is data input/output, switch to it now + */ + + ns->state = ns->nxstate; + ns->nxstate = ns->op[++ns->stateidx + 1]; + ns->regs.num = ns->regs.count = 0; + + NS_DBG("switch_state: the next state is data I/O, switch, " + "state: %s, nxstate: %s\n", + get_state_name(ns->state), get_state_name(ns->nxstate)); + + /* + * Set the internal register to the count of bytes which + * are expected to be input or output + */ + switch (NS_STATE(ns->state)) { + case STATE_DATAIN: + case STATE_DATAOUT: + ns->regs.num = ns->geom.pgszoob - ns->regs.off - ns->regs.column; + break; + + case STATE_DATAOUT_ID: + ns->regs.num = ns->geom.idbytes; + break; + + case STATE_DATAOUT_STATUS: + ns->regs.count = ns->regs.num = 0; + break; + + default: + NS_ERR("switch_state: BUG! unknown data state\n"); + } + + } else if (ns->nxstate & STATE_ADDR_MASK) { + /* + * If the next state is address input, set the internal + * register to the number of expected address bytes + */ + + ns->regs.count = 0; + + switch (NS_STATE(ns->nxstate)) { + case STATE_ADDR_PAGE: + ns->regs.num = ns->geom.pgaddrbytes; + + break; + case STATE_ADDR_SEC: + ns->regs.num = ns->geom.secaddrbytes; + break; + + case STATE_ADDR_ZERO: + ns->regs.num = 1; + break; + + case STATE_ADDR_COLUMN: + /* Column address is always 2 bytes */ + ns->regs.num = ns->geom.pgaddrbytes - ns->geom.secaddrbytes; + break; + + default: + NS_ERR("switch_state: BUG! unknown address state\n"); + } + } else { + /* + * Just reset internal counters. + */ + + ns->regs.num = 0; + ns->regs.count = 0; + } +} + +static u_char ns_nand_read_byte(struct mtd_info *mtd) +{ + struct nand_chip *chip = mtd_to_nand(mtd); + struct nandsim *ns = nand_get_controller_data(chip); + u_char outb = 0x00; + + /* Sanity and correctness checks */ + if (!ns->lines.ce) { + NS_ERR("read_byte: chip is disabled, return %#x\n", (uint)outb); + return outb; + } + if (ns->lines.ale || ns->lines.cle) { + NS_ERR("read_byte: ALE or CLE pin is high, return %#x\n", (uint)outb); + return outb; + } + if (!(ns->state & STATE_DATAOUT_MASK)) { + NS_WARN("read_byte: unexpected data output cycle, state is %s " + "return %#x\n", get_state_name(ns->state), (uint)outb); + return outb; + } + + /* Status register may be read as many times as it is wanted */ + if (NS_STATE(ns->state) == STATE_DATAOUT_STATUS) { + NS_DBG("read_byte: return %#x status\n", ns->regs.status); + return ns->regs.status; + } + + /* Check if there is any data in the internal buffer which may be read */ + if (ns->regs.count == ns->regs.num) { + NS_WARN("read_byte: no more data to output, return %#x\n", (uint)outb); + return outb; + } + + switch (NS_STATE(ns->state)) { + case STATE_DATAOUT: + if (ns->busw == 8) { + outb = ns->buf.byte[ns->regs.count]; + ns->regs.count += 1; + } else { + outb = (u_char)cpu_to_le16(ns->buf.word[ns->regs.count >> 1]); + ns->regs.count += 2; + } + break; + case STATE_DATAOUT_ID: + NS_DBG("read_byte: read ID byte %d, total = %d\n", ns->regs.count, ns->regs.num); + outb = ns->ids[ns->regs.count]; + ns->regs.count += 1; + break; + default: + BUG(); + } + + if (ns->regs.count == ns->regs.num) { + NS_DBG("read_byte: all bytes were read\n"); + + if (NS_STATE(ns->nxstate) == STATE_READY) + switch_state(ns); + } + + return outb; +} + +static void ns_nand_write_byte(struct mtd_info *mtd, u_char byte) +{ + struct nand_chip *chip = mtd_to_nand(mtd); + struct nandsim *ns = nand_get_controller_data(chip); + + /* Sanity and correctness checks */ + if (!ns->lines.ce) { + NS_ERR("write_byte: chip is disabled, ignore write\n"); + return; + } + if (ns->lines.ale && ns->lines.cle) { + NS_ERR("write_byte: ALE and CLE pins are high simultaneously, ignore write\n"); + return; + } + + if (ns->lines.cle == 1) { + /* + * The byte written is a command. + */ + + if (byte == NAND_CMD_RESET) { + NS_LOG("reset chip\n"); + switch_to_ready_state(ns, NS_STATUS_OK(ns)); + return; + } + + /* Check that the command byte is correct */ + if (check_command(byte)) { + NS_ERR("write_byte: unknown command %#x\n", (uint)byte); + return; + } + + if (NS_STATE(ns->state) == STATE_DATAOUT_STATUS + || NS_STATE(ns->state) == STATE_DATAOUT) { + int row = ns->regs.row; + + switch_state(ns); + if (byte == NAND_CMD_RNDOUT) + ns->regs.row = row; + } + + /* Check if chip is expecting command */ + if (NS_STATE(ns->nxstate) != STATE_UNKNOWN && !(ns->nxstate & STATE_CMD_MASK)) { + /* Do not warn if only 2 id bytes are read */ + if (!(ns->regs.command == NAND_CMD_READID && + NS_STATE(ns->state) == STATE_DATAOUT_ID && ns->regs.count == 2)) { + /* + * We are in situation when something else (not command) + * was expected but command was input. In this case ignore + * previous command(s)/state(s) and accept the last one. + */ + NS_WARN("write_byte: command (%#x) wasn't expected, expected state is %s, " + "ignore previous states\n", (uint)byte, get_state_name(ns->nxstate)); + } + switch_to_ready_state(ns, NS_STATUS_FAILED(ns)); + } + + NS_DBG("command byte corresponding to %s state accepted\n", + get_state_name(get_state_by_command(byte))); + ns->regs.command = byte; + switch_state(ns); + + } else if (ns->lines.ale == 1) { + /* + * The byte written is an address. + */ + + if (NS_STATE(ns->nxstate) == STATE_UNKNOWN) { + + NS_DBG("write_byte: operation isn't known yet, identify it\n"); + + if (find_operation(ns, 1) < 0) + return; + + if ((ns->state & ACTION_MASK) && do_state_action(ns, ns->state) < 0) { + switch_to_ready_state(ns, NS_STATUS_FAILED(ns)); + return; + } + + ns->regs.count = 0; + switch (NS_STATE(ns->nxstate)) { + case STATE_ADDR_PAGE: + ns->regs.num = ns->geom.pgaddrbytes; + break; + case STATE_ADDR_SEC: + ns->regs.num = ns->geom.secaddrbytes; + break; + case STATE_ADDR_ZERO: + ns->regs.num = 1; + break; + default: + BUG(); + } + } + + /* Check that chip is expecting address */ + if (!(ns->nxstate & STATE_ADDR_MASK)) { + NS_ERR("write_byte: address (%#x) isn't expected, expected state is %s, " + "switch to STATE_READY\n", (uint)byte, get_state_name(ns->nxstate)); + switch_to_ready_state(ns, NS_STATUS_FAILED(ns)); + return; + } + + /* Check if this is expected byte */ + if (ns->regs.count == ns->regs.num) { + NS_ERR("write_byte: no more address bytes expected\n"); + switch_to_ready_state(ns, NS_STATUS_FAILED(ns)); + return; + } + + accept_addr_byte(ns, byte); + + ns->regs.count += 1; + + NS_DBG("write_byte: address byte %#x was accepted (%d bytes input, %d expected)\n", + (uint)byte, ns->regs.count, ns->regs.num); + + if (ns->regs.count == ns->regs.num) { + NS_DBG("address (%#x, %#x) is accepted\n", ns->regs.row, ns->regs.column); + switch_state(ns); + } + + } else { + /* + * The byte written is an input data. + */ + + /* Check that chip is expecting data input */ + if (!(ns->state & STATE_DATAIN_MASK)) { + NS_ERR("write_byte: data input (%#x) isn't expected, state is %s, " + "switch to %s\n", (uint)byte, + get_state_name(ns->state), get_state_name(STATE_READY)); + switch_to_ready_state(ns, NS_STATUS_FAILED(ns)); + return; + } + + /* Check if this is expected byte */ + if (ns->regs.count == ns->regs.num) { + NS_WARN("write_byte: %u input bytes has already been accepted, ignore write\n", + ns->regs.num); + return; + } + + if (ns->busw == 8) { + ns->buf.byte[ns->regs.count] = byte; + ns->regs.count += 1; + } else { + ns->buf.word[ns->regs.count >> 1] = cpu_to_le16((uint16_t)byte); + ns->regs.count += 2; + } + } + + return; +} + +static void ns_hwcontrol(struct mtd_info *mtd, int cmd, unsigned int bitmask) +{ + struct nand_chip *chip = mtd_to_nand(mtd); + struct nandsim *ns = nand_get_controller_data(chip); + + ns->lines.cle = bitmask & NAND_CLE ? 1 : 0; + ns->lines.ale = bitmask & NAND_ALE ? 1 : 0; + ns->lines.ce = bitmask & NAND_NCE ? 1 : 0; + + if (cmd != NAND_CMD_NONE) + ns_nand_write_byte(mtd, cmd); +} + +static int ns_device_ready(struct mtd_info *mtd) +{ + NS_DBG("device_ready\n"); + return 1; +} + +static uint16_t ns_nand_read_word(struct mtd_info *mtd) +{ + struct nand_chip *chip = mtd_to_nand(mtd); + + NS_DBG("read_word\n"); + + return chip->read_byte(mtd) | (chip->read_byte(mtd) << 8); +} + +static void ns_nand_write_buf(struct mtd_info *mtd, const u_char *buf, int len) +{ + struct nand_chip *chip = mtd_to_nand(mtd); + struct nandsim *ns = nand_get_controller_data(chip); + + /* Check that chip is expecting data input */ + if (!(ns->state & STATE_DATAIN_MASK)) { + NS_ERR("write_buf: data input isn't expected, state is %s, " + "switch to STATE_READY\n", get_state_name(ns->state)); + switch_to_ready_state(ns, NS_STATUS_FAILED(ns)); + return; + } + + /* Check if these are expected bytes */ + if (ns->regs.count + len > ns->regs.num) { + NS_ERR("write_buf: too many input bytes\n"); + switch_to_ready_state(ns, NS_STATUS_FAILED(ns)); + return; + } + + memcpy(ns->buf.byte + ns->regs.count, buf, len); + ns->regs.count += len; + + if (ns->regs.count == ns->regs.num) { + NS_DBG("write_buf: %d bytes were written\n", ns->regs.count); + } +} + +static void ns_nand_read_buf(struct mtd_info *mtd, u_char *buf, int len) +{ + struct nand_chip *chip = mtd_to_nand(mtd); + struct nandsim *ns = nand_get_controller_data(chip); + + /* Sanity and correctness checks */ + if (!ns->lines.ce) { + NS_ERR("read_buf: chip is disabled\n"); + return; + } + if (ns->lines.ale || ns->lines.cle) { + NS_ERR("read_buf: ALE or CLE pin is high\n"); + return; + } + if (!(ns->state & STATE_DATAOUT_MASK)) { + NS_WARN("read_buf: unexpected data output cycle, current state is %s\n", + get_state_name(ns->state)); + return; + } + + if (NS_STATE(ns->state) != STATE_DATAOUT) { + int i; + + for (i = 0; i < len; i++) + buf[i] = mtd_to_nand(mtd)->read_byte(mtd); + + return; + } + + /* Check if these are expected bytes */ + if (ns->regs.count + len > ns->regs.num) { + NS_ERR("read_buf: too many bytes to read\n"); + switch_to_ready_state(ns, NS_STATUS_FAILED(ns)); + return; + } + + memcpy(buf, ns->buf.byte + ns->regs.count, len); + ns->regs.count += len; + + if (ns->regs.count == ns->regs.num) { + if (NS_STATE(ns->nxstate) == STATE_READY) + switch_state(ns); + } + + return; +} + +/* + * Module initialization function + */ +static int __init ns_init_module(void) +{ + struct nand_chip *chip; + struct nandsim *nand; + int retval = -ENOMEM, i; + + if (bus_width != 8 && bus_width != 16) { + NS_ERR("wrong bus width (%d), use only 8 or 16\n", bus_width); + return -EINVAL; + } + + /* Allocate and initialize mtd_info, nand_chip and nandsim structures */ + chip = kzalloc(sizeof(struct nand_chip) + sizeof(struct nandsim), + GFP_KERNEL); + if (!chip) { + NS_ERR("unable to allocate core structures.\n"); + return -ENOMEM; + } + nsmtd = nand_to_mtd(chip); + nand = (struct nandsim *)(chip + 1); + nand_set_controller_data(chip, (void *)nand); + + /* + * Register simulator's callbacks. + */ + chip->cmd_ctrl = ns_hwcontrol; + chip->read_byte = ns_nand_read_byte; + chip->dev_ready = ns_device_ready; + chip->write_buf = ns_nand_write_buf; + chip->read_buf = ns_nand_read_buf; + chip->read_word = ns_nand_read_word; + chip->ecc.mode = NAND_ECC_SOFT; + chip->ecc.algo = NAND_ECC_HAMMING; + /* The NAND_SKIP_BBTSCAN option is necessary for 'overridesize' */ + /* and 'badblocks' parameters to work */ + chip->options |= NAND_SKIP_BBTSCAN; + + switch (bbt) { + case 2: + chip->bbt_options |= NAND_BBT_NO_OOB; + case 1: + chip->bbt_options |= NAND_BBT_USE_FLASH; + case 0: + break; + default: + NS_ERR("bbt has to be 0..2\n"); + retval = -EINVAL; + goto error; + } + /* + * Perform minimum nandsim structure initialization to handle + * the initial ID read command correctly + */ + if (id_bytes[6] != 0xFF || id_bytes[7] != 0xFF) + nand->geom.idbytes = 8; + else if (id_bytes[4] != 0xFF || id_bytes[5] != 0xFF) + nand->geom.idbytes = 6; + else if (id_bytes[2] != 0xFF || id_bytes[3] != 0xFF) + nand->geom.idbytes = 4; + else + nand->geom.idbytes = 2; + nand->regs.status = NS_STATUS_OK(nand); + nand->nxstate = STATE_UNKNOWN; + nand->options |= OPT_PAGE512; /* temporary value */ + memcpy(nand->ids, id_bytes, sizeof(nand->ids)); + if (bus_width == 16) { + nand->busw = 16; + chip->options |= NAND_BUSWIDTH_16; + } + + nsmtd->owner = THIS_MODULE; + + if ((retval = parse_weakblocks()) != 0) + goto error; + + if ((retval = parse_weakpages()) != 0) + goto error; + + if ((retval = parse_gravepages()) != 0) + goto error; + + retval = nand_scan_ident(nsmtd, 1, NULL); + if (retval) { + NS_ERR("cannot scan NAND Simulator device\n"); + goto error; + } + + if (bch) { + unsigned int eccsteps, eccbytes; + if (!mtd_nand_has_bch()) { + NS_ERR("BCH ECC support is disabled\n"); + retval = -EINVAL; + goto error; + } + /* use 512-byte ecc blocks */ + eccsteps = nsmtd->writesize/512; + eccbytes = (bch*13+7)/8; + /* do not bother supporting small page devices */ + if ((nsmtd->oobsize < 64) || !eccsteps) { + NS_ERR("bch not available on small page devices\n"); + retval = -EINVAL; + goto error; + } + if ((eccbytes*eccsteps+2) > nsmtd->oobsize) { + NS_ERR("invalid bch value %u\n", bch); + retval = -EINVAL; + goto error; + } + chip->ecc.mode = NAND_ECC_SOFT; + chip->ecc.algo = NAND_ECC_BCH; + chip->ecc.size = 512; + chip->ecc.strength = bch; + chip->ecc.bytes = eccbytes; + NS_INFO("using %u-bit/%u bytes BCH ECC\n", bch, chip->ecc.size); + } + + retval = nand_scan_tail(nsmtd); + if (retval) { + NS_ERR("can't register NAND Simulator\n"); + goto error; + } + + if (overridesize) { + uint64_t new_size = (uint64_t)nsmtd->erasesize << overridesize; + if (new_size >> overridesize != nsmtd->erasesize) { + NS_ERR("overridesize is too big\n"); + retval = -EINVAL; + goto err_exit; + } + /* N.B. This relies on nand_scan not doing anything with the size before we change it */ + nsmtd->size = new_size; + chip->chipsize = new_size; + chip->chip_shift = ffs(nsmtd->erasesize) + overridesize - 1; + chip->pagemask = (chip->chipsize >> chip->page_shift) - 1; + } + + if ((retval = setup_wear_reporting(nsmtd)) != 0) + goto err_exit; + + if ((retval = init_nandsim(nsmtd)) != 0) + goto err_exit; + + if ((retval = chip->scan_bbt(nsmtd)) != 0) + goto err_exit; + + if ((retval = parse_badblocks(nand, nsmtd)) != 0) + goto err_exit; + + /* Register NAND partitions */ + retval = mtd_device_register(nsmtd, &nand->partitions[0], + nand->nbparts); + if (retval != 0) + goto err_exit; + + if ((retval = nandsim_debugfs_create(nand)) != 0) + goto err_exit; + + return 0; + +err_exit: + free_nandsim(nand); + nand_release(nsmtd); + for (i = 0;i < ARRAY_SIZE(nand->partitions); ++i) + kfree(nand->partitions[i].name); +error: + kfree(chip); + free_lists(); + + return retval; +} + +module_init(ns_init_module); + +/* + * Module clean-up function + */ +static void __exit ns_cleanup_module(void) +{ + struct nand_chip *chip = mtd_to_nand(nsmtd); + struct nandsim *ns = nand_get_controller_data(chip); + int i; + + free_nandsim(ns); /* Free nandsim private resources */ + nand_release(nsmtd); /* Unregister driver */ + for (i = 0;i < ARRAY_SIZE(ns->partitions); ++i) + kfree(ns->partitions[i].name); + kfree(mtd_to_nand(nsmtd)); /* Free other structures */ + free_lists(); +} + +module_exit(ns_cleanup_module); + +MODULE_LICENSE ("GPL"); +MODULE_AUTHOR ("Artem B. Bityuckiy"); +MODULE_DESCRIPTION ("The NAND flash simulator"); |