mtd: nand: add 'oob_required' argument to NAND {read,write}_page inte…

…rfaces

New NAND controllers can perform read/write via HW engines which don't expose
OOB data in their DMA mode. To reflect this, we should rework the nand_chip /
nand_ecc_ctrl interfaces that assume that drivers will always read/write OOB
data in the nand_chip.oob_poi buffer. A better interface includes a boolean
argument that explicitly tells the callee when OOB data is requested by the
calling layer (for reading/writing to/from nand_chip.oob_poi).

This patch adds the 'oob_required' parameter to each relevant {read,write}_page
interface; all 'oob_required' parameters are left unused for now. The next
patch will set the parameter properly in the nand_base.c callers, and follow-up
patches will make use of 'oob_required' in some of the callee functions.

Note that currently, there is no harm in ignoring the 'oob_required' parameter
and *always* utilizing nand_chip.oob_poi, but there can be
performance/complexity/design benefits from avoiding filling oob_poi in the
common case. I will try to implement this for some drivers which can be ported
easily.

Note: I couldn't compile-test all of these easily, as some had ARCH
dependencies.

[dwmw2: Merge later 1/0 vs. true/false cleanup]
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Reviewed-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
Acked-by: Jiandong Zheng <jdzheng@broadcom.com>
Acked-by: Mike Dunn <mikedunn@newsguy.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

drivers/mtd/nand/atmel_nand.c

@@ -324,9 +324,10 @@ static int atmel_nand_calculate(struct mtd_info *mtd,
  * mtd:        mtd info structure
  * chip:       nand chip info structure
  * buf:        buffer to store read data
+ * oob_required:    caller expects OOB data read to chip->oob_poi
  */
-static int atmel_nand_read_page(struct mtd_info *mtd,
-		struct nand_chip *chip, uint8_t *buf, int page)
+static int atmel_nand_read_page(struct mtd_info *mtd, struct nand_chip *chip,
+				uint8_t *buf, int oob_required, int page)
 {
 	int eccsize = chip->ecc.size;
 	int eccbytes = chip->ecc.bytes;

drivers/mtd/nand/bcm_umi_bch.c

@@ -22,9 +22,9 @@
 
 /* ---- Private Function Prototypes -------------------------------------- */
 static int bcm_umi_bch_read_page_hwecc(struct mtd_info *mtd,
-	struct nand_chip *chip, uint8_t *buf, int page);
+	struct nand_chip *chip, uint8_t *buf, int oob_required, int page);
 static void bcm_umi_bch_write_page_hwecc(struct mtd_info *mtd,
-	struct nand_chip *chip, const uint8_t *buf);
+	struct nand_chip *chip, const uint8_t *buf, int oob_required);
 
 /* ---- Private Variables ------------------------------------------------ */
 
@@ -103,11 +103,12 @@ static struct nand_ecclayout nand_hw_eccoob_4096 = {
 *  @mtd:	mtd info structure
 *  @chip:	nand chip info structure
 *  @buf:	buffer to store read data
+*  @oob_required:	caller expects OOB data read to chip->oob_poi
 *
 ***************************************************************************/
 static int bcm_umi_bch_read_page_hwecc(struct mtd_info *mtd,
 				       struct nand_chip *chip, uint8_t * buf,
-						 int page)
+				       int oob_required, int page)
 {
 	int sectorIdx = 0;
 	int eccsize = chip->ecc.size;
@@ -190,10 +191,11 @@ static int bcm_umi_bch_read_page_hwecc(struct mtd_info *mtd,
 *  @mtd:	mtd info structure
 *  @chip:	nand chip info structure
 *  @buf:	data buffer
+*  @oob_required:	must write chip->oob_poi to OOB
 *
 ***************************************************************************/
 static void bcm_umi_bch_write_page_hwecc(struct mtd_info *mtd,
-	struct nand_chip *chip, const uint8_t *buf)
+	struct nand_chip *chip, const uint8_t *buf, int oob_required)
 {
 	int sectorIdx = 0;
 	int eccsize = chip->ecc.size;

drivers/mtd/nand/bcm_umi_nand.c

@@ -341,7 +341,7 @@ static int bcm_umi_nand_verify_buf(struct mtd_info *mtd, const u_char * buf,
 	 * for MLC parts which may have permanently stuck bits.
 	 */
 	struct nand_chip *chip = mtd->priv;
-	int ret = chip->ecc.read_page(mtd, chip, readbackbuf, 0);
+	int ret = chip->ecc.read_page(mtd, chip, readbackbuf, 0, 0);
 	if (ret < 0)
 		return -EFAULT;
 	else {

drivers/mtd/nand/bf5xx_nand.c

@@ -558,7 +558,7 @@ static void bf5xx_nand_dma_write_buf(struct mtd_info *mtd,
 }
 
 static int bf5xx_nand_read_page_raw(struct mtd_info *mtd, struct nand_chip *chip,
-		uint8_t *buf, int page)
+		uint8_t *buf, int oob_required, int page)
 {
 	bf5xx_nand_read_buf(mtd, buf, mtd->writesize);
 	bf5xx_nand_read_buf(mtd, chip->oob_poi, mtd->oobsize);
@@ -567,7 +567,7 @@ static int bf5xx_nand_read_page_raw(struct mtd_info *mtd, struct nand_chip *chip
 }
 
 static void bf5xx_nand_write_page_raw(struct mtd_info *mtd, struct nand_chip *chip,
-		const uint8_t *buf)
+		const uint8_t *buf, int oob_required)
 {
 	bf5xx_nand_write_buf(mtd, buf, mtd->writesize);
 	bf5xx_nand_write_buf(mtd, chip->oob_poi, mtd->oobsize);

drivers/mtd/nand/cafe_nand.c

@@ -375,12 +375,13 @@ static int cafe_nand_read_oob(struct mtd_info *mtd, struct nand_chip *chip,
  * @mtd:	mtd info structure
  * @chip:	nand chip info structure
  * @buf:	buffer to store read data
+ * @oob_required:	caller expects OOB data read to chip->oob_poi
  *
  * The hw generator calculates the error syndrome automatically. Therefor
  * we need a special oob layout and handling.
  */
 static int cafe_nand_read_page(struct mtd_info *mtd, struct nand_chip *chip,
-			       uint8_t *buf, int page)
+			       uint8_t *buf, int oob_required, int page)
 {
 	struct cafe_priv *cafe = mtd->priv;
 	unsigned int max_bitflips = 0;
@@ -520,7 +521,8 @@ static struct nand_bbt_descr cafe_bbt_mirror_descr_512 = {
 
 
 static void cafe_nand_write_page_lowlevel(struct mtd_info *mtd,
-					  struct nand_chip *chip, const uint8_t *buf)
+					  struct nand_chip *chip,
+					  const uint8_t *buf, int oob_required)
 {
 	struct cafe_priv *cafe = mtd->priv;
 
@@ -532,16 +534,17 @@ static void cafe_nand_write_page_lowlevel(struct mtd_info *mtd,
 }
 
 static int cafe_nand_write_page(struct mtd_info *mtd, struct nand_chip *chip,
-				const uint8_t *buf, int page, int cached, int raw)
+				const uint8_t *buf, int oob_required, int page,
+				int cached, int raw)
 {
 	int status;
 
 	chip->cmdfunc(mtd, NAND_CMD_SEQIN, 0x00, page);
 
 	if (unlikely(raw))
-		chip->ecc.write_page_raw(mtd, chip, buf);
+		chip->ecc.write_page_raw(mtd, chip, buf, oob_required);
 	else
-		chip->ecc.write_page(mtd, chip, buf);
+		chip->ecc.write_page(mtd, chip, buf, oob_required);
 
 	/*
 	 * Cached progamming disabled for now, Not sure if its worth the

drivers/mtd/nand/denali.c

@@ -1087,7 +1087,7 @@ static void write_page(struct mtd_info *mtd, struct nand_chip *chip,
  * by write_page above.
  * */
 static void denali_write_page(struct mtd_info *mtd, struct nand_chip *chip,
-				const uint8_t *buf)
+				const uint8_t *buf, int oob_required)
 {
 	/* for regular page writes, we let HW handle all the ECC
 	 * data written to the device. */
@@ -1099,7 +1099,7 @@ static void denali_write_page(struct mtd_info *mtd, struct nand_chip *chip,
  * write_page() function above.
  */
 static void denali_write_page_raw(struct mtd_info *mtd, struct nand_chip *chip,
-					const uint8_t *buf)
+					const uint8_t *buf, int oob_required)
 {
 	/* for raw page writes, we want to disable ECC and simply write
 	   whatever data is in the buffer. */
@@ -1122,7 +1122,7 @@ static int denali_read_oob(struct mtd_info *mtd, struct nand_chip *chip,
 }
 
 static int denali_read_page(struct mtd_info *mtd, struct nand_chip *chip,
-			    uint8_t *buf, int page)
+			    uint8_t *buf, int oob_required, int page)
 {
 	unsigned int max_bitflips;
 	struct denali_nand_info *denali = mtd_to_denali(mtd);
@@ -1175,7 +1175,7 @@ static int denali_read_page(struct mtd_info *mtd, struct nand_chip *chip,
 }
 
 static int denali_read_page_raw(struct mtd_info *mtd, struct nand_chip *chip,
-				uint8_t *buf, int page)
+				uint8_t *buf, int oob_required, int page)
 {
 	struct denali_nand_info *denali = mtd_to_denali(mtd);
 

drivers/mtd/nand/docg4.c

@@ -787,13 +787,13 @@ static int read_page(struct mtd_info *mtd, struct nand_chip *nand,
 
 
 static int docg4_read_page_raw(struct mtd_info *mtd, struct nand_chip *nand,
-			       uint8_t *buf, int page)
+			       uint8_t *buf, int oob_required, int page)
 {
 	return read_page(mtd, nand, buf, page, false);
 }
 
 static int docg4_read_page(struct mtd_info *mtd, struct nand_chip *nand,
-			   uint8_t *buf, int page)
+			   uint8_t *buf, int oob_required, int page)
 {
 	return read_page(mtd, nand, buf, page, true);
 }
@@ -953,13 +953,13 @@ static void write_page(struct mtd_info *mtd, struct nand_chip *nand,
 }
 
 static void docg4_write_page_raw(struct mtd_info *mtd, struct nand_chip *nand,
-				 const uint8_t *buf)
+				 const uint8_t *buf, int oob_required)
 {
 	return write_page(mtd, nand, buf, false);
 }
 
 static void docg4_write_page(struct mtd_info *mtd, struct nand_chip *nand,
-			     const uint8_t *buf)
+			     const uint8_t *buf, int oob_required)
 {
 	return write_page(mtd, nand, buf, true);
 }
@@ -1003,7 +1003,7 @@ static int __init read_factory_bbt(struct mtd_info *mtd)
 		return -ENOMEM;
 
 	read_page_prologue(mtd, g4_addr);
-	status = docg4_read_page(mtd, nand, buf, DOCG4_FACTORY_BBT_PAGE);
+	status = docg4_read_page(mtd, nand, buf, 0, DOCG4_FACTORY_BBT_PAGE);
 	if (status)
 		goto exit;
 
@@ -1080,7 +1080,7 @@ static int docg4_block_markbad(struct mtd_info *mtd, loff_t ofs)
 
 	/* write first page of block */
 	write_page_prologue(mtd, g4_addr);
-	docg4_write_page(mtd, nand, buf);
+	docg4_write_page(mtd, nand, buf, 1);
 	ret = pageprog(mtd);
 	if (!ret)
 		mtd->ecc_stats.badblocks++;

drivers/mtd/nand/fsl_elbc_nand.c

@@ -746,10 +746,8 @@ static int fsl_elbc_chip_init_tail(struct mtd_info *mtd)
 	return 0;
 }
 
-static int fsl_elbc_read_page(struct mtd_info *mtd,
-                              struct nand_chip *chip,
-			      uint8_t *buf,
-			      int page)
+static int fsl_elbc_read_page(struct mtd_info *mtd, struct nand_chip *chip,
+			      uint8_t *buf, int oob_required, int page)
 {
 	struct fsl_elbc_mtd *priv = chip->priv;
 	struct fsl_lbc_ctrl *ctrl = priv->ctrl;
@@ -767,9 +765,8 @@ static int fsl_elbc_read_page(struct mtd_info *mtd,
 /* ECC will be calculated automatically, and errors will be detected in
  * waitfunc.
  */
-static void fsl_elbc_write_page(struct mtd_info *mtd,
-                                struct nand_chip *chip,
-                                const uint8_t *buf)
+static void fsl_elbc_write_page(struct mtd_info *mtd, struct nand_chip *chip,
+				const uint8_t *buf, int oob_required)
 {
 	fsl_elbc_write_buf(mtd, buf, mtd->writesize);
 	fsl_elbc_write_buf(mtd, chip->oob_poi, mtd->oobsize);

drivers/mtd/nand/fsl_ifc_nand.c

@@ -698,9 +698,8 @@ static int fsl_ifc_wait(struct mtd_info *mtd, struct nand_chip *chip)
 	return nand_fsr | NAND_STATUS_WP;
 }
 
-static int fsl_ifc_read_page(struct mtd_info *mtd,
-			      struct nand_chip *chip,
-			      uint8_t *buf, int page)
+static int fsl_ifc_read_page(struct mtd_info *mtd, struct nand_chip *chip,
+			     uint8_t *buf, int oob_required, int page)
 {
 	struct fsl_ifc_mtd *priv = chip->priv;
 	struct fsl_ifc_ctrl *ctrl = priv->ctrl;
@@ -721,9 +720,8 @@ static int fsl_ifc_read_page(struct mtd_info *mtd,
 /* ECC will be calculated automatically, and errors will be detected in
  * waitfunc.
  */
-static void fsl_ifc_write_page(struct mtd_info *mtd,
-				struct nand_chip *chip,
-				const uint8_t *buf)
+static void fsl_ifc_write_page(struct mtd_info *mtd, struct nand_chip *chip,
+			       const uint8_t *buf, int oob_required)
 {
 	fsl_ifc_write_buf(mtd, buf, mtd->writesize);
 	fsl_ifc_write_buf(mtd, chip->oob_poi, mtd->oobsize);

drivers/mtd/nand/fsmc_nand.c

@@ -692,6 +692,7 @@ static void fsmc_write_buf_dma(struct mtd_info *mtd, const uint8_t *buf,
  * @mtd:	mtd info structure
  * @chip:	nand chip info structure
  * @buf:	buffer to store read data
+ * @oob_required:	caller expects OOB data read to chip->oob_poi
  * @page:	page number to read
  *
  * This routine is needed for fsmc version 8 as reading from NAND chip has to be
@@ -701,7 +702,7 @@ static void fsmc_write_buf_dma(struct mtd_info *mtd, const uint8_t *buf,
  * max of 8 bits)
  */
 static int fsmc_read_page_hwecc(struct mtd_info *mtd, struct nand_chip *chip,
-				 uint8_t *buf, int page)
+				 uint8_t *buf, int oob_required, int page)
 {
 	struct fsmc_nand_data *host = container_of(mtd,
 					struct fsmc_nand_data, mtd);

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

@@ -842,7 +842,7 @@ static void block_mark_swapping(struct gpmi_nand_data *this,
 }
 
 static int gpmi_ecc_read_page(struct mtd_info *mtd, struct nand_chip *chip,
-				uint8_t *buf, int page)
+				uint8_t *buf, int oob_required, int page)
 {
 	struct gpmi_nand_data *this = chip->priv;
 	struct bch_geometry *nfc_geo = &this->bch_geometry;
@@ -928,8 +928,8 @@ static int gpmi_ecc_read_page(struct mtd_info *mtd, struct nand_chip *chip,
 	return ret;
 }
 
-static void gpmi_ecc_write_page(struct mtd_info *mtd,
-				struct nand_chip *chip, const uint8_t *buf)
+static void gpmi_ecc_write_page(struct mtd_info *mtd, struct nand_chip *chip,
+				const uint8_t *buf, int oob_required)
 {
 	struct gpmi_nand_data *this = chip->priv;
 	struct bch_geometry *nfc_geo = &this->bch_geometry;
@@ -1309,7 +1309,7 @@ static int mx23_write_transcription_stamp(struct gpmi_nand_data *this)
 		/* Write the first page of the current stride. */
 		dev_dbg(dev, "Writing an NCB fingerprint in page 0x%x\n", page);
 		chip->cmdfunc(mtd, NAND_CMD_SEQIN, 0x00, page);
-		chip->ecc.write_page_raw(mtd, chip, buffer);
+		chip->ecc.write_page_raw(mtd, chip, buffer, 0);
 		chip->cmdfunc(mtd, NAND_CMD_PAGEPROG, -1, -1);
 
 		/* Wait for the write to finish. */