--- /dev/null
+/*
+ * 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/nand.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/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
+
+struct nandsim_debug_info {
+ struct dentry *dfs_root;
+ struct dentry *dfs_wear_report;
+};
+
+/*
+ * 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;
+
+ struct nandsim_debug_info dbg;
+};
+
+/*
+ * 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 nandsim_debug_info *dbg = &dev->dbg;
+ struct dentry *dent;
+ int err;
+
+ if (!IS_ENABLED(CONFIG_DEBUG_FS))
+ return 0;
+
+ dent = debugfs_create_dir("nandsim", NULL);
+ if (IS_ERR_OR_NULL(dent)) {
+ int err = dent ? -ENODEV : PTR_ERR(dent);
+
+ NS_ERR("cannot create \"nandsim\" debugfs directory, err %d\n",
+ err);
+ return err;
+ }
+ dbg->dfs_root = dent;
+
+ dent = debugfs_create_file("wear_report", S_IRUSR,
+ dbg->dfs_root, dev, &dfs_fops);
+ if (IS_ERR_OR_NULL(dent))
+ goto out_remove;
+ dbg->dfs_wear_report = dent;
+
+ return 0;
+
+out_remove:
+ debugfs_remove_recursive(dbg->dfs_root);
+ err = dent ? PTR_ERR(dent) : -ENODEV;
+ return err;
+}
+
+/**
+ * nandsim_debugfs_remove - destroy all debugfs files
+ */
+static void nandsim_debugfs_remove(struct nandsim *ns)
+{
+ if (IS_ENABLED(CONFIG_DEBUG_FS))
+ debugfs_remove_recursive(ns->dbg.dfs_root);
+}
+
+/*
+ * 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 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 *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_nandsim(struct mtd_info *mtd)
+{
+ struct nand_chip *chip = mtd->priv;
+ struct nandsim *ns = chip->priv;
+ 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");
+ ret = -EINVAL;
+ goto error;
+ }
+ 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");
+ ret = -EINVAL;
+ goto error;
+ }
+ ns->partitions[i].name = get_partition_name(i);
+ 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");
+ ret = -EINVAL;
+ goto error;
+ }
+ ns->partitions[i].name = get_partition_name(i);
+ 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)
+ goto error;
+
+ /* 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);
+ ret = -ENOMEM;
+ goto error;
+ }
+ memset(ns->buf.byte, 0xFF, ns->geom.pgszoob);
+
+ return 0;
+
+error:
+ free_device(ns);
+
+ return ret;
+}
+
+/*
+ * 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 weakpagess.\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++)
+ page_cache_release(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_CACHE_SHIFT;
+ end_index = (pos + count - 1) >> PAGE_CACHE_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 int set_memalloc(void)
+{
+ if (current->flags & PF_MEMALLOC)
+ return 0;
+ current->flags |= PF_MEMALLOC;
+ return 1;
+}
+
+static void clear_memalloc(int memalloc)
+{
+ if (memalloc)
+ current->flags &= ~PF_MEMALLOC;
+}
+
+static ssize_t read_file(struct nandsim *ns, struct file *file, void *buf, size_t count, loff_t pos)
+{
+ ssize_t tx;
+ int err, memalloc;
+
+ err = get_pages(ns, file, count, pos);
+ if (err)
+ return err;
+ memalloc = set_memalloc();
+ tx = kernel_read(file, pos, buf, count);
+ clear_memalloc(memalloc);
+ 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, memalloc;
+
+ err = get_pages(ns, file, count, pos);
+ if (err)
+ return err;
+ memalloc = set_memalloc();
+ tx = kernel_write(file, buf, count, pos);
+ clear_memalloc(memalloc);
+ 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 nandsim *ns = ((struct nand_chip *)mtd->priv)->priv;
+ 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 nandsim *ns = ((struct nand_chip *)mtd->priv)->priv;
+
+ /* 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 nandsim *ns = ((struct nand_chip *)mtd->priv)->priv;
+
+ 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 = (struct nand_chip *)mtd->priv;
+
+ 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 nandsim *ns = ((struct nand_chip *)mtd->priv)->priv;
+
+ /* 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 nandsim *ns = ((struct nand_chip *)mtd->priv)->priv;
+
+ /* 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] = ((struct nand_chip *)mtd->priv)->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 */
+ nsmtd = kzalloc(sizeof(struct mtd_info) + sizeof(struct nand_chip)
+ + sizeof(struct nandsim), GFP_KERNEL);
+ if (!nsmtd) {
+ NS_ERR("unable to allocate core structures.\n");
+ return -ENOMEM;
+ }
+ chip = (struct nand_chip *)(nsmtd + 1);
+ nsmtd->priv = (void *)chip;
+ nand = (struct nandsim *)(chip + 1);
+ chip->priv = (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;
+ /* 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");
+ if (retval > 0)
+ retval = -ENXIO;
+ 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_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");
+ if (retval > 0)
+ retval = -ENXIO;
+ 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 = nandsim_debugfs_create(nand)) != 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;
+
+ 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(nsmtd);
+ free_lists();
+
+ return retval;
+}
+
+module_init(ns_init_module);
+
+/*
+ * Module clean-up function
+ */
+static void __exit ns_cleanup_module(void)
+{
+ struct nandsim *ns = ((struct nand_chip *)nsmtd->priv)->priv;
+ int i;
+
+ nandsim_debugfs_remove(ns);
+ 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(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");
Code Review / kvmfornfv.git / blobdiff