mtd: nand: Drop unused cached programming support

Cached programming is always skipped, so drop the associated code until
we decide to really support it.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
[Linux commit: 0b4773fd1649e0d418275557723a7ef54f769dc9]
[masahiro: modify davinci_nand.c for U-Boot]
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

drivers/mtd/nand/davinci_nand.c

@@ -358,13 +358,12 @@ static struct nand_ecclayout nand_keystone_rbl_4bit_layout_oobfirst = {
  * @buf: the data to write
  * @oob_required: must write chip->oob_poi to OOB
  * @page: page number to write
- * @cached: cached programming
  * @raw: use _raw version of write_page
  */
 static int nand_davinci_write_page(struct mtd_info *mtd, struct nand_chip *chip,
 				   uint32_t offset, int data_len,
 				   const uint8_t *buf, int oob_required,
-				   int page, int cached, int raw)
+				   int page, int raw)
 {
 	int status;
 	int ret = 0;

drivers/mtd/nand/nand_base.c

@@ -2409,12 +2409,11 @@ static int nand_write_page_syndrome(struct mtd_info *mtd,
  * @buf: the data to write
  * @oob_required: must write chip->oob_poi to OOB
  * @page: page number to write
- * @cached: cached programming
  * @raw: use _raw version of write_page
  */
 static int nand_write_page(struct mtd_info *mtd, struct nand_chip *chip,
 		uint32_t offset, int data_len, const uint8_t *buf,
-		int oob_required, int page, int cached, int raw)
+		int oob_required, int page, int raw)
 {
 	int status, subpage;
 
@@ -2440,31 +2439,19 @@ static int nand_write_page(struct mtd_info *mtd, struct nand_chip *chip,
 	if (status < 0)
 		return status;
 
+	if (nand_standard_page_accessors(&chip->ecc))
+		chip->cmdfunc(mtd, NAND_CMD_PAGEPROG, -1, -1);
+	status = chip->waitfunc(mtd, chip);
 	/*
-	 * Cached progamming disabled for now. Not sure if it's worth the
-	 * trouble. The speed gain is not very impressive. (2.3->2.6Mib/s).
+	 * See if operation failed and additional status checks are
+	 * available.
 	 */
-	cached = 0;
-
-	if (!cached || !NAND_HAS_CACHEPROG(chip)) {
-
-		if (nand_standard_page_accessors(&chip->ecc))
-			chip->cmdfunc(mtd, NAND_CMD_PAGEPROG, -1, -1);
-		status = chip->waitfunc(mtd, chip);
-		/*
-		 * See if operation failed and additional status checks are
-		 * available.
-		 */
-		if ((status & NAND_STATUS_FAIL) && (chip->errstat))
-			status = chip->errstat(mtd, chip, FL_WRITING, status,
-					       page);
+	if ((status & NAND_STATUS_FAIL) && (chip->errstat))
+		status = chip->errstat(mtd, chip, FL_WRITING, status,
+				       page);
 
-		if (status & NAND_STATUS_FAIL)
-			return -EIO;
-	} else {
-		chip->cmdfunc(mtd, NAND_CMD_CACHEDPROG, -1, -1);
-		status = chip->waitfunc(mtd, chip);
-	}
+	if (status & NAND_STATUS_FAIL)
+		return -EIO;
 
 	return 0;
 }
@@ -2538,7 +2525,7 @@ static uint8_t *nand_fill_oob(struct mtd_info *mtd, uint8_t *oob, size_t len,
 static int nand_do_write_ops(struct mtd_info *mtd, loff_t to,
 			     struct mtd_oob_ops *ops)
 {
-	int chipnr, realpage, page, blockmask, column;
+	int chipnr, realpage, page, column;
 	struct nand_chip *chip = mtd_to_nand(mtd);
 	uint32_t writelen = ops->len;
 
@@ -2574,7 +2561,6 @@ static int nand_do_write_ops(struct mtd_info *mtd, loff_t to,
 
 	realpage = (int)(to >> chip->page_shift);
 	page = realpage & chip->pagemask;
-	blockmask = (1 << (chip->phys_erase_shift - chip->page_shift)) - 1;
 
 	/* Invalidate the page cache, when we write to the cached page */
 	if (to <= ((loff_t)chip->pagebuf << chip->page_shift) &&
@@ -2589,7 +2575,6 @@ static int nand_do_write_ops(struct mtd_info *mtd, loff_t to,
 
 	while (1) {
 		int bytes = mtd->writesize;
-		int cached = writelen > bytes && page != blockmask;
 		uint8_t *wbuf = buf;
 		int use_bufpoi;
 		int part_pagewr = (column || writelen < mtd->writesize);
@@ -2604,7 +2589,6 @@ static int nand_do_write_ops(struct mtd_info *mtd, loff_t to,
 		if (use_bufpoi) {
 			pr_debug("%s: using write bounce buffer for buf@%p\n",
 					 __func__, buf);
-			cached = 0;
 			if (part_pagewr)
 				bytes = min_t(int, bytes - column, writelen);
 			chip->pagebuf = -1;
@@ -2622,7 +2606,7 @@ static int nand_do_write_ops(struct mtd_info *mtd, loff_t to,
 			memset(chip->oob_poi, 0xff, mtd->oobsize);
 		}
 		ret = chip->write_page(mtd, chip, column, bytes, wbuf,
-					oob_required, page, cached,
+					oob_required, page,
 					(ops->mode == MTD_OPS_RAW));
 		if (ret)
 			break;

include/linux/mtd/nand.h

@@ -849,7 +849,7 @@ struct nand_chip {
 			int status, int page);
 	int (*write_page)(struct mtd_info *mtd, struct nand_chip *chip,
 			uint32_t offset, int data_len, const uint8_t *buf,
-			int oob_required, int page, int cached, int raw);
+			int oob_required, int page, int raw);
 	int (*onfi_set_features)(struct mtd_info *mtd, struct nand_chip *chip,
 			int feature_addr, uint8_t *subfeature_para);
 	int (*onfi_get_features)(struct mtd_info *mtd, struct nand_chip *chip,