[MTD] NAND: Fix bad block table scan for small page devices

Scan 1st and 2nd pages of SP devices for BB marker by default.
Fix more then one page scanning in create_bbt.c.

Signed-off-by: Artem B. Bityuckiy <dedekind@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

diff --git a/drivers/mtd/nand/nand_bbt.c b/drivers/mtd/nand/nand_bbt.c
index 5ff6eba..c85c69d 100644 (file)
--- a/drivers/mtd/nand/nand_bbt.c
+++ b/drivers/mtd/nand/nand_bbt.c
@@ -6,7 +6,7 @@
  *   
  *  Copyright (C) 2004 Thomas Gleixner (tglx@linutronix.de)
  *
- * $Id: nand_bbt.c,v 1.30 2005/02/11 10:14:12 dedekind Exp $
+ * $Id: nand_bbt.c,v 1.31 2005/02/16 17:09:36 dedekind Exp $
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
@@ -77,17 +77,17 @@
 */
 static int check_pattern (uint8_t *buf, int len, int paglen, struct nand_bbt_descr *td)
 {
-       int i, end;
+       int i, end = 0;
        uint8_t *p = buf;
 
-       end = paglen + td->offs;
        if (td->options & NAND_BBT_SCANEMPTY) {
+               end = paglen + td->offs;
                for (i = 0; i < end; i++) {
                        if (p[i] != 0xff)
                                return -1;
                }
+               p += end;
        }       
-       p += end;
        
        /* Compare the pattern */
        for (i = 0; i < td->len; i++) {
@@ -95,9 +95,9 @@ static int check_pattern (uint8_t *buf, int len, int paglen, struct nand_bbt_des
                        return -1;
        }
 
-       p += td->len;
-       end += td->len;
        if (td->options & NAND_BBT_SCANEMPTY) {
+               p += td->len;
+               end += td->len;
                for (i = end; i < len; i++) {
                        if (*p++ != 0xff)
                                return -1;
@@ -255,7 +255,7 @@ static int read_abs_bbts (struct mtd_info *mtd, uint8_t *buf, struct nand_bbt_de
 static int create_bbt (struct mtd_info *mtd, uint8_t *buf, struct nand_bbt_descr *bd, int chip)
 {
        struct nand_chip *this = mtd->priv;
-       int i, j, numblocks, len, scanlen, pagelen;
+       int i, j, numblocks, len, scanlen;
        int startblock;
        loff_t from;
        size_t readlen, ooblen;
@@ -270,17 +270,16 @@ static int create_bbt (struct mtd_info *mtd, uint8_t *buf, struct nand_bbt_descr
                else    
                        len = 1;
        }
-       
-       if (bd->options == 0) {
-               /* Memory-based BBT. We may read only needed bytes from the OOB area to
-                * test if block is bad, no need to read the whole page content. */
-               scanlen = ooblen = pagelen = 0;
+
+       if (!(bd->options & NAND_BBT_SCANEMPTY)) {
+               /* We need only read few bytes from the OOB area */
+               scanlen = ooblen = 0;
                readlen = bd->len;
        } else {
+               /* Full page content should be read */
                scanlen = mtd->oobblock + mtd->oobsize;
                readlen = len * mtd->oobblock;
                ooblen = len * mtd->oobsize;
-               pagelen = mtd->oobblock;
        }
 
        if (chip == -1) {
@@ -293,7 +292,7 @@ static int create_bbt (struct mtd_info *mtd, uint8_t *buf, struct nand_bbt_descr
                if (chip >= this->numchips) {
                        printk (KERN_WARNING "create_bbt(): chipnr (%d) > available chips (%d)\n",
                                chip + 1, this->numchips);
-                       return -EINVAL; 
+                       return -EINVAL;
                }
                numblocks = this->chipsize >> (this->bbt_erase_shift - 1);
                startblock = chip * numblocks;
@@ -304,16 +303,21 @@ static int create_bbt (struct mtd_info *mtd, uint8_t *buf, struct nand_bbt_descr
        for (i = startblock; i < numblocks;) {
                int ret;
                
-               if (bd->options == 0) {
-                       size_t retlen;
-                       if ((ret = mtd->read_oob(mtd, from + bd->offs, bd->len, &retlen, &buf[bd->offs])))
-                               return ret;
-               } else {
+               if (bd->options & NAND_BBT_SCANEMPTY)
                        if ((ret = nand_read_raw (mtd, buf, from, readlen, ooblen)))
                                return ret;
-               }
+
                for (j = 0; j < len; j++) {
-                       if (check_pattern (&buf[j * scanlen], scanlen, pagelen, bd)) {
+                       if (!(bd->options & NAND_BBT_SCANEMPTY)) {
+                               size_t retlen;
+                               
+                               /* No need to read pages fully, just read required OOB bytes */
+                               ret = mtd->read_oob(mtd, from + j * mtd->oobblock + bd->offs,
+                                                       readlen, &retlen, &buf[0]);
+                               if (ret)
+                                       return ret;
+                       }
+                       if (check_pattern (&buf[j * scanlen], scanlen, mtd->oobblock, bd)) {
                                this->bbt[i >> 3] |= 0x03 << (i & 0x6);
                                printk (KERN_WARNING "Bad eraseblock %d at 0x%08x\n", 
                                        i >> 1, (unsigned int) from);
@@ -323,6 +327,7 @@ static int create_bbt (struct mtd_info *mtd, uint8_t *buf, struct nand_bbt_descr
                i += 2;
                from += (1 << this->bbt_erase_shift);
        }
+
        return 0;
 }
 
@@ -608,12 +613,11 @@ write:
  * The function creates a memory based bbt by scanning the device 
  * for manufacturer / software marked good / bad blocks
 */
-static int nand_memory_bbt (struct mtd_info *mtd, struct nand_bbt_descr *bd)
+static inline int nand_memory_bbt (struct mtd_info *mtd, struct nand_bbt_descr *bd)
 {
        struct nand_chip *this = mtd->priv;
 
-       /* Ensure that we only scan for the pattern and nothing else */
-       bd->options = 0;
+       bd->options &= ~NAND_BBT_SCANEMPTY;
        return create_bbt (mtd, this->data_buf, bd, -1);
 }
 
@@ -928,14 +932,11 @@ out:
 }
 
 /* Define some generic bad / good block scan pattern which are used 
- * while scanning a device for factory marked good / bad blocks
- * 
- * The memory based patterns just 
- */
+ * while scanning a device for factory marked good / bad blocks. */
 static uint8_t scan_ff_pattern[] = { 0xff, 0xff };
 
 static struct nand_bbt_descr smallpage_memorybased = {
-       .options = 0,
+       .options = NAND_BBT_SCAN2NDPAGE,
        .offs = 5,
        .len = 1,
        .pattern = scan_ff_pattern