mtd: nand: refactor chip->block_markbad interface

The chip->block_markbad pointer should really only be responsible for
writing a bad block marker for new bad blocks. It should not take care
of BBT-related functionality, nor should it handle bookkeeping of bad
block stats.

This patch refactors the 3 users of the block_markbad interface (plus
the default nand_base implementation) so that the common code is kept in
nand_block_markbad_lowlevel(). It removes some inconsistencies between
the various implementations and should allow for more centralized
improvements in the future.

Because gpmi-nand no longer needs the nand_update_bbt() function, let's
stop exporting it as well.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Acked-by: Huang Shijie <b32955@freescale.com> (for gpmi-nand parts)
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

drivers/mtd/nand/docg4.c

@@ -1093,7 +1093,6 @@ static int docg4_block_markbad(struct mtd_info *mtd, loff_t ofs)
 	struct nand_chip *nand = mtd->priv;
 	struct docg4_priv *doc = nand->priv;
 	struct nand_bbt_descr *bbtd = nand->badblock_pattern;
-	int block = (int)(ofs >> nand->bbt_erase_shift);
 	int page = (int)(ofs >> nand->page_shift);
 	uint32_t g4_addr = mtd_to_docg4_address(page, 0);
 
@@ -1108,9 +1107,6 @@ static int docg4_block_markbad(struct mtd_info *mtd, loff_t ofs)
 	if (buf == NULL)
 		return -ENOMEM;
 
-	/* update bbt in memory */
-	nand->bbt[block / 4] |= 0x01 << ((block & 0x03) * 2);
-
 	/* write bit-wise negation of pattern to oob buffer */
 	memset(nand->oob_poi, 0xff, mtd->oobsize);
 	for (i = 0; i < bbtd->len; i++)
@@ -1120,8 +1116,6 @@ static int docg4_block_markbad(struct mtd_info *mtd, loff_t ofs)
 	write_page_prologue(mtd, g4_addr);
 	docg4_write_page(mtd, nand, buf, 1);
 	ret = pageprog(mtd);
-	if (!ret)
-		mtd->ecc_stats.badblocks++;
 
 	kfree(buf);
 

drivers/mtd/nand/gpmi-nand/gpmi-nand.c

@@ -1148,43 +1148,31 @@ static int gpmi_block_markbad(struct mtd_info *mtd, loff_t ofs)
 {
 	struct nand_chip *chip = mtd->priv;
 	struct gpmi_nand_data *this = chip->priv;
-	int block, ret = 0;
+	int ret = 0;
 	uint8_t *block_mark;
 	int column, page, status, chipnr;
 
-	/* Get block number */
-	block = (int)(ofs >> chip->bbt_erase_shift);
-	if (chip->bbt)
-		chip->bbt[block >> 2] |= 0x01 << ((block & 0x03) << 1);
+	chipnr = (int)(ofs >> chip->chip_shift);
+	chip->select_chip(mtd, chipnr);
 
-	/* Do we have a flash based bad block table ? */
-	if (chip->bbt_options & NAND_BBT_USE_FLASH)
-		ret = nand_update_bbt(mtd, ofs);
-	else {
-		chipnr = (int)(ofs >> chip->chip_shift);
-		chip->select_chip(mtd, chipnr);
+	column = this->swap_block_mark ? mtd->writesize : 0;
 
-		column = this->swap_block_mark ? mtd->writesize : 0;
+	/* Write the block mark. */
+	block_mark = this->data_buffer_dma;
+	block_mark[0] = 0; /* bad block marker */
 
-		/* Write the block mark. */
-		block_mark = this->data_buffer_dma;
-		block_mark[0] = 0; /* bad block marker */
+	/* Shift to get page */
+	page = (int)(ofs >> chip->page_shift);
 
-		/* Shift to get page */
-		page = (int)(ofs >> chip->page_shift);
+	chip->cmdfunc(mtd, NAND_CMD_SEQIN, column, page);
+	chip->write_buf(mtd, block_mark, 1);
+	chip->cmdfunc(mtd, NAND_CMD_PAGEPROG, -1, -1);
 
-		chip->cmdfunc(mtd, NAND_CMD_SEQIN, column, page);
-		chip->write_buf(mtd, block_mark, 1);
-		chip->cmdfunc(mtd, NAND_CMD_PAGEPROG, -1, -1);
+	status = chip->waitfunc(mtd, chip);
+	if (status & NAND_STATUS_FAIL)
+		ret = -EIO;
 
-		status = chip->waitfunc(mtd, chip);
-		if (status & NAND_STATUS_FAIL)
-			ret = -EIO;
-
-		chip->select_chip(mtd, -1);
-	}
-	if (!ret)
-		mtd->ecc_stats.badblocks++;
+	chip->select_chip(mtd, -1);
 
 	return ret;
 }

drivers/mtd/nand/nand_base.c

@@ -324,13 +324,58 @@ static int nand_block_bad(struct mtd_info *mtd, loff_t ofs, int getchip)
 }
 
 /**
- * nand_default_block_markbad - [DEFAULT] mark a block bad
+ * nand_default_block_markbad - [DEFAULT] mark a block bad via bad block marker
  * @mtd: MTD device structure
  * @ofs: offset from device start
  *
  * This is the default implementation, which can be overridden by a hardware
- * specific driver. We try operations in the following order, according to our
- * bbt_options (NAND_BBT_NO_OOB_BBM and NAND_BBT_USE_FLASH):
+ * specific driver. It provides the details for writing a bad block marker to a
+ * block.
+ */
+static int nand_default_block_markbad(struct mtd_info *mtd, loff_t ofs)
+{
+	struct nand_chip *chip = mtd->priv;
+	struct mtd_oob_ops ops;
+	uint8_t buf[2] = { 0, 0 };
+	int ret = 0, res, i = 0;
+
+	ops.datbuf = NULL;
+	ops.oobbuf = buf;
+	ops.ooboffs = chip->badblockpos;
+	if (chip->options & NAND_BUSWIDTH_16) {
+		ops.ooboffs &= ~0x01;
+		ops.len = ops.ooblen = 2;
+	} else {
+		ops.len = ops.ooblen = 1;
+	}
+	ops.mode = MTD_OPS_PLACE_OOB;
+
+	/* Write to first/last page(s) if necessary */
+	if (chip->bbt_options & NAND_BBT_SCANLASTPAGE)
+		ofs += mtd->erasesize - mtd->writesize;
+	do {
+		res = nand_do_write_oob(mtd, ofs, &ops);
+		if (!ret)
+			ret = res;
+
+		i++;
+		ofs += mtd->writesize;
+	} while ((chip->bbt_options & NAND_BBT_SCAN2NDPAGE) && i < 2);
+
+	return ret;
+}
+
+/**
+ * nand_block_markbad_lowlevel - mark a block bad
+ * @mtd: MTD device structure
+ * @ofs: offset from device start
+ *
+ * This function performs the generic NAND bad block marking steps (i.e., bad
+ * block table(s) and/or marker(s)). We only allow the hardware driver to
+ * specify how to write bad block markers to OOB (chip->block_markbad).
+ *
+ * We try operations in the following order, according to our bbt_options
+ * (NAND_BBT_NO_OOB_BBM and NAND_BBT_USE_FLASH):
  *  (1) erase the affected block, to allow OOB marker to be written cleanly
  *  (2) update in-memory BBT
  *  (3) write bad block marker to OOB area of affected block
@@ -338,11 +383,10 @@ static int nand_block_bad(struct mtd_info *mtd, loff_t ofs, int getchip)
  * Note that we retain the first error encountered in (3) or (4), finish the
  * procedures, and dump the error in the end.
 */
-static int nand_default_block_markbad(struct mtd_info *mtd, loff_t ofs)
+static int nand_block_markbad_lowlevel(struct mtd_info *mtd, loff_t ofs)
 {
 	struct nand_chip *chip = mtd->priv;
-	uint8_t buf[2] = { 0, 0 };
-	int block, res, ret = 0, i = 0;
+	int block, res, ret = 0;
 	int write_oob = !(chip->bbt_options & NAND_BBT_NO_OOB_BBM);
 
 	if (write_oob) {
@@ -364,34 +408,8 @@ static int nand_default_block_markbad(struct mtd_info *mtd, loff_t ofs)
 
 	/* Write bad block marker to OOB */
 	if (write_oob) {
-		struct mtd_oob_ops ops;
-		loff_t wr_ofs = ofs;
-
 		nand_get_device(mtd, FL_WRITING);
-
-		ops.datbuf = NULL;
-		ops.oobbuf = buf;
-		ops.ooboffs = chip->badblockpos;
-		if (chip->options & NAND_BUSWIDTH_16) {
-			ops.ooboffs &= ~0x01;
-			ops.len = ops.ooblen = 2;
-		} else {
-			ops.len = ops.ooblen = 1;
-		}
-		ops.mode = MTD_OPS_PLACE_OOB;
-
-		/* Write to first/last page(s) if necessary */
-		if (chip->bbt_options & NAND_BBT_SCANLASTPAGE)
-			wr_ofs += mtd->erasesize - mtd->writesize;
-		do {
-			res = nand_do_write_oob(mtd, wr_ofs, &ops);
-			if (!ret)
-				ret = res;
-
-			i++;
-			wr_ofs += mtd->writesize;
-		} while ((chip->bbt_options & NAND_BBT_SCAN2NDPAGE) && i < 2);
-
+		ret = chip->block_markbad(mtd, ofs);
 		nand_release_device(mtd);
 	}
 
@@ -2683,7 +2701,6 @@ static int nand_block_isbad(struct mtd_info *mtd, loff_t offs)
  */
 static int nand_block_markbad(struct mtd_info *mtd, loff_t ofs)
 {
-	struct nand_chip *chip = mtd->priv;
 	int ret;
 
 	ret = nand_block_isbad(mtd, ofs);
@@ -2694,7 +2711,7 @@ static int nand_block_markbad(struct mtd_info *mtd, loff_t ofs)
 		return ret;
 	}
 
-	return chip->block_markbad(mtd, ofs);
+	return nand_block_markbad_lowlevel(mtd, ofs);
 }
 
 /**

drivers/mtd/nand/nand_bbt.c

@@ -1392,4 +1392,3 @@ int nand_isbad_bbt(struct mtd_info *mtd, loff_t offs, int allowbbt)
 
 EXPORT_SYMBOL(nand_scan_bbt);
 EXPORT_SYMBOL(nand_default_bbt);
-EXPORT_SYMBOL_GPL(nand_update_bbt);

drivers/mtd/nand/sm_common.c

@@ -42,7 +42,7 @@ static int sm_block_markbad(struct mtd_info *mtd, loff_t ofs)
 {
 	struct mtd_oob_ops ops;
 	struct sm_oob oob;
-	int ret, error = 0;
+	int ret;
 
 	memset(&oob, -1, SM_OOB_SIZE);
 	oob.block_status = 0x0F;
@@ -61,11 +61,10 @@ static int sm_block_markbad(struct mtd_info *mtd, loff_t ofs)
 		printk(KERN_NOTICE
 			"sm_common: can't mark sector at %i as bad\n",
 								(int)ofs);
-		error = -EIO;
-	} else
-		mtd->ecc_stats.badblocks++;
+		return -EIO;
+	}
 
-	return error;
+	return 0;
 }
 
 static struct nand_flash_dev nand_smartmedia_flash_ids[] = {