--- zzzz-none-000/linux-4.4.60/drivers/mtd/nand/nand_base.c	2017-04-08 07:53:53.000000000 +0000
+++ dragonfly-4020-701/linux-4.4.60/drivers/mtd/nand/nand_base.c	2018-11-08 13:36:17.000000000 +0000
@@ -92,6 +92,26 @@
 		 .length = 78} }
 };
 
+static struct nand_ecclayout nand_oob_256 = {
+	.eccbytes = 96,
+	.eccpos = {
+		160, 161, 162, 163, 164, 165, 166, 167,
+		168, 169, 170, 171, 172, 173, 174, 175,
+		176, 177, 178, 179, 180, 181, 182, 183,
+		184, 185, 186, 187, 188, 189, 190, 191,
+		192, 193, 194, 195, 196, 197, 198, 199,
+		200, 201, 202, 203, 204, 205, 206, 207,
+		208, 209, 210, 211, 212, 213, 214, 215,
+		216, 217, 218, 219, 220, 221, 222, 223,
+		224, 225, 226, 227, 228, 229, 230, 231,
+		232, 233, 234, 235, 236, 237, 238, 239,
+		240, 241, 242, 243, 244, 245, 246, 247,
+		248, 249, 250, 251, 252, 253, 254, 255},
+	.oobfree = {
+		{.offset = 2,
+		 .length = 158} }
+};
+
 static int nand_get_device(struct mtd_info *mtd, int new_state);
 
 static int nand_do_write_oob(struct mtd_info *mtd, loff_t to,
@@ -317,9 +337,9 @@
  *
  * Check, if the block is bad.
  */
-static int nand_block_bad(struct mtd_info *mtd, loff_t ofs, int getchip)
+static int nand_block_bad(struct mtd_info *mtd, loff_t ofs)
 {
-	int page, chipnr, res = 0, i = 0;
+	int page, res = 0, i = 0;
 	struct nand_chip *chip = mtd->priv;
 	u16 bad;
 
@@ -328,15 +348,6 @@
 
 	page = (int)(ofs >> chip->page_shift) & chip->pagemask;
 
-	if (getchip) {
-		chipnr = (int)(ofs >> chip->chip_shift);
-
-		nand_get_device(mtd, FL_READING);
-
-		/* Select the NAND device */
-		chip->select_chip(mtd, chipnr);
-	}
-
 	do {
 		if (chip->options & NAND_BUSWIDTH_16) {
 			chip->cmdfunc(mtd, NAND_CMD_READOOB,
@@ -361,11 +372,6 @@
 		i++;
 	} while (!res && i < 2 && (chip->bbt_options & NAND_BBT_SCAN2NDPAGE));
 
-	if (getchip) {
-		chip->select_chip(mtd, -1);
-		nand_release_device(mtd);
-	}
-
 	return res;
 }
 
@@ -394,7 +400,11 @@
 	} else {
 		ops.len = ops.ooblen = 1;
 	}
-	ops.mode = MTD_OPS_PLACE_OOB;
+
+	if (unlikely(chip->bbt_options & NAND_BBT_ACCESS_BBM_RAW))
+		ops.mode = MTD_OPS_RAW;
+	else
+		ops.mode = MTD_OPS_PLACE_OOB;
 
 	/* Write to first/last page(s) if necessary */
 	if (chip->bbt_options & NAND_BBT_SCANLASTPAGE)
@@ -503,19 +513,17 @@
  * nand_block_checkbad - [GENERIC] Check if a block is marked bad
  * @mtd: MTD device structure
  * @ofs: offset from device start
- * @getchip: 0, if the chip is already selected
  * @allowbbt: 1, if its allowed to access the bbt area
  *
  * Check, if the block is bad. Either by reading the bad block table or
  * calling of the scan function.
  */
-static int nand_block_checkbad(struct mtd_info *mtd, loff_t ofs, int getchip,
-			       int allowbbt)
+static int nand_block_checkbad(struct mtd_info *mtd, loff_t ofs, int allowbbt)
 {
 	struct nand_chip *chip = mtd->priv;
 
 	if (!chip->bbt)
-		return chip->block_bad(mtd, ofs, getchip);
+		return chip->block_bad(mtd, ofs);
 
 	/* Return info from the table */
 	return nand_isbad_bbt(mtd, ofs, allowbbt);
@@ -2023,6 +2031,7 @@
 static int nand_do_read_oob(struct mtd_info *mtd, loff_t from,
 			    struct mtd_oob_ops *ops)
 {
+	unsigned int max_bitflips = 0;
 	int page, realpage, chipnr;
 	struct nand_chip *chip = mtd->priv;
 	struct mtd_ecc_stats stats;
@@ -2083,6 +2092,8 @@
 				nand_wait_ready(mtd);
 		}
 
+		max_bitflips = max_t(unsigned int, max_bitflips, ret);
+
 		readlen -= len;
 		if (!readlen)
 			break;
@@ -2108,7 +2119,7 @@
 	if (mtd->ecc_stats.failed - stats.failed)
 		return -EBADMSG;
 
-	return  mtd->ecc_stats.corrected - stats.corrected ? -EUCLEAN : 0;
+	return max_bitflips;
 }
 
 /**
@@ -2918,7 +2929,7 @@
 	while (len) {
 		/* Check if we have a bad block, we do not erase bad blocks! */
 		if (nand_block_checkbad(mtd, ((loff_t) page) <<
-					chip->page_shift, 0, allowbbt)) {
+					chip->page_shift, allowbbt)) {
 			pr_warn("%s: attempt to erase a bad block at page 0x%08x\n",
 				    __func__, page);
 			instr->state = MTD_ERASE_FAILED;
@@ -3005,7 +3016,20 @@
  */
 static int nand_block_isbad(struct mtd_info *mtd, loff_t offs)
 {
-	return nand_block_checkbad(mtd, offs, 1, 0);
+	struct nand_chip *chip = mtd_to_nand(mtd);
+	int chipnr = (int)(offs >> chip->chip_shift);
+	int ret;
+
+	/* Select the NAND device */
+	nand_get_device(mtd, FL_READING);
+	chip->select_chip(mtd, chipnr);
+
+	ret = nand_block_checkbad(mtd, offs, 0);
+
+	chip->select_chip(mtd, -1);
+	nand_release_device(mtd);
+
+	return ret;
 }
 
 /**
@@ -3741,7 +3765,13 @@
 				 maf_id == NAND_MFR_AMD ||
 				 maf_id == NAND_MFR_MACRONIX)) ||
 			(mtd->writesize == 2048 &&
-			 maf_id == NAND_MFR_MICRON))
+			 maf_id == NAND_MFR_MICRON) ||
+			(mtd->writesize == 2048 &&
+			 maf_id == NAND_MFR_GIGA) ||
+			(mtd->writesize == 2048 &&
+			 maf_id == NAND_MFR_MACRONIX) ||
+			(mtd->writesize == 2048 &&
+			 maf_id == NAND_MFR_WINBOND))
 		chip->bbt_options |= NAND_BBT_SCAN2NDPAGE;
 }
 
@@ -4127,6 +4157,9 @@
 		case 128:
 			ecc->layout = &nand_oob_128;
 			break;
+		case 256:
+			ecc->layout = &nand_oob_256;
+			break;
 		default:
 			pr_warn("No oob scheme defined for oobsize %d\n",
 				   mtd->oobsize);