Merge v4.5-rc1 with MTD -next development

To start from a good base.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
diff --git a/drivers/mtd/bcm47xxpart.c b/drivers/mtd/bcm47xxpart.c
index 8282f47..845dd27 100644
--- a/drivers/mtd/bcm47xxpart.c
+++ b/drivers/mtd/bcm47xxpart.c
@@ -66,11 +66,13 @@
 {
 	uint32_t buf;
 	size_t bytes_read;
+	int err;
 
-	if (mtd_read(master, offset, sizeof(buf), &bytes_read,
-		     (uint8_t *)&buf) < 0) {
-		pr_err("mtd_read error while parsing (offset: 0x%X)!\n",
-			offset);
+	err  = mtd_read(master, offset, sizeof(buf), &bytes_read,
+			(uint8_t *)&buf);
+	if (err && !mtd_is_bitflip(err)) {
+		pr_err("mtd_read error while parsing (offset: 0x%X): %d\n",
+			offset, err);
 		goto out_default;
 	}
 
@@ -95,6 +97,7 @@
 	int trx_part = -1;
 	int last_trx_part = -1;
 	int possible_nvram_sizes[] = { 0x8000, 0xF000, 0x10000, };
+	int err;
 
 	/*
 	 * Some really old flashes (like AT45DB*) had smaller erasesize-s, but
@@ -118,8 +121,8 @@
 	/* Parse block by block looking for magics */
 	for (offset = 0; offset <= master->size - blocksize;
 	     offset += blocksize) {
-		/* Nothing more in higher memory */
-		if (offset >= 0x2000000)
+		/* Nothing more in higher memory on BCM47XX (MIPS) */
+		if (config_enabled(CONFIG_BCM47XX) && offset >= 0x2000000)
 			break;
 
 		if (curr_part >= BCM47XXPART_MAX_PARTS) {
@@ -128,10 +131,11 @@
 		}
 
 		/* Read beginning of the block */
-		if (mtd_read(master, offset, BCM47XXPART_BYTES_TO_READ,
-			     &bytes_read, (uint8_t *)buf) < 0) {
-			pr_err("mtd_read error while parsing (offset: 0x%X)!\n",
-			       offset);
+		err = mtd_read(master, offset, BCM47XXPART_BYTES_TO_READ,
+			       &bytes_read, (uint8_t *)buf);
+		if (err && !mtd_is_bitflip(err)) {
+			pr_err("mtd_read error while parsing (offset: 0x%X): %d\n",
+			       offset, err);
 			continue;
 		}
 
@@ -254,10 +258,11 @@
 		}
 
 		/* Read middle of the block */
-		if (mtd_read(master, offset + 0x8000, 0x4,
-			     &bytes_read, (uint8_t *)buf) < 0) {
-			pr_err("mtd_read error while parsing (offset: 0x%X)!\n",
-			       offset);
+		err = mtd_read(master, offset + 0x8000, 0x4, &bytes_read,
+			       (uint8_t *)buf);
+		if (err && !mtd_is_bitflip(err)) {
+			pr_err("mtd_read error while parsing (offset: 0x%X): %d\n",
+			       offset, err);
 			continue;
 		}
 
@@ -277,10 +282,11 @@
 		}
 
 		offset = master->size - possible_nvram_sizes[i];
-		if (mtd_read(master, offset, 0x4, &bytes_read,
-			     (uint8_t *)buf) < 0) {
-			pr_err("mtd_read error while reading at offset 0x%X!\n",
-			       offset);
+		err = mtd_read(master, offset, 0x4, &bytes_read,
+			       (uint8_t *)buf);
+		if (err && !mtd_is_bitflip(err)) {
+			pr_err("mtd_read error while reading (offset 0x%X): %d\n",
+			       offset, err);
 			continue;
 		}
 
diff --git a/drivers/mtd/nand/atmel_nand.c b/drivers/mtd/nand/atmel_nand.c
index bddcf83..affe7a7 100644
--- a/drivers/mtd/nand/atmel_nand.c
+++ b/drivers/mtd/nand/atmel_nand.c
@@ -825,7 +825,7 @@
 			*(buf + byte_pos) ^= (1 << bit_pos);
 
 			pos = sector_num * host->pmecc_sector_size + byte_pos;
-			dev_info(host->dev, "Bit flip in data area, byte_pos: %d, bit_pos: %d, 0x%02x -> 0x%02x\n",
+			dev_dbg(host->dev, "Bit flip in data area, byte_pos: %d, bit_pos: %d, 0x%02x -> 0x%02x\n",
 				pos, bit_pos, err_byte, *(buf + byte_pos));
 		} else {
 			/* Bit flip in OOB area */
@@ -835,7 +835,7 @@
 			ecc[tmp] ^= (1 << bit_pos);
 
 			pos = tmp + nand_chip->ecc.layout->eccpos[0];
-			dev_info(host->dev, "Bit flip in OOB, oob_byte_pos: %d, bit_pos: %d, 0x%02x -> 0x%02x\n",
+			dev_dbg(host->dev, "Bit flip in OOB, oob_byte_pos: %d, bit_pos: %d, 0x%02x -> 0x%02x\n",
 				pos, bit_pos, err_byte, ecc[tmp]);
 		}
 
@@ -1486,8 +1486,6 @@
 		ecc_writel(host->ecc, CR, ATMEL_ECC_RST);
 }
 
-static const struct of_device_id atmel_nand_dt_ids[];
-
 static int atmel_of_init_port(struct atmel_nand_host *host,
 			      struct device_node *np)
 {
@@ -1498,7 +1496,7 @@
 	enum of_gpio_flags flags = 0;
 
 	host->caps = (struct atmel_nand_caps *)
-		of_match_device(atmel_nand_dt_ids, host->dev)->data;
+		of_device_get_match_data(host->dev);
 
 	if (of_property_read_u32(np, "atmel,nand-addr-offset", &val) == 0) {
 		if (val >= 32) {
@@ -1550,7 +1548,7 @@
 		if ((val != 2) && (val != 4) && (val != 8) && (val != 12) &&
 				(val != 24)) {
 			dev_err(host->dev,
-				"Unsupported PMECC correction capability: %d; should be 2, 4, 8, 12 or 24\n",
+				"Required ECC strength not supported: %u\n",
 				val);
 			return -EINVAL;
 		}
@@ -1560,7 +1558,7 @@
 	if (of_property_read_u32(np, "atmel,pmecc-sector-size", &val) == 0) {
 		if ((val != 512) && (val != 1024)) {
 			dev_err(host->dev,
-				"Unsupported PMECC sector size: %d; should be 512 or 1024 bytes\n",
+				"Required ECC sector size not supported: %u\n",
 				val);
 			return -EINVAL;
 		}
diff --git a/drivers/mtd/nand/gpmi-nand/gpmi-nand.c b/drivers/mtd/nand/gpmi-nand/gpmi-nand.c
index 235ddcb..8122c69 100644
--- a/drivers/mtd/nand/gpmi-nand/gpmi-nand.c
+++ b/drivers/mtd/nand/gpmi-nand/gpmi-nand.c
@@ -1,7 +1,7 @@
 /*
  * Freescale GPMI NAND Flash Driver
  *
- * Copyright (C) 2010-2011 Freescale Semiconductor, Inc.
+ * Copyright (C) 2010-2015 Freescale Semiconductor, Inc.
  * Copyright (C) 2008 Embedded Alley Solutions, Inc.
  *
  * This program is free software; you can redistribute it and/or modify
@@ -136,7 +136,7 @@
  *
  * We may have available oob space in this case.
  */
-static bool set_geometry_by_ecc_info(struct gpmi_nand_data *this)
+static int set_geometry_by_ecc_info(struct gpmi_nand_data *this)
 {
 	struct bch_geometry *geo = &this->bch_geometry;
 	struct nand_chip *chip = &this->nand;
@@ -145,7 +145,7 @@
 	unsigned int block_mark_bit_offset;
 
 	if (!(chip->ecc_strength_ds > 0 && chip->ecc_step_ds > 0))
-		return false;
+		return -EINVAL;
 
 	switch (chip->ecc_step_ds) {
 	case SZ_512:
@@ -158,19 +158,19 @@
 		dev_err(this->dev,
 			"unsupported nand chip. ecc bits : %d, ecc size : %d\n",
 			chip->ecc_strength_ds, chip->ecc_step_ds);
-		return false;
+		return -EINVAL;
 	}
 	geo->ecc_chunk_size = chip->ecc_step_ds;
 	geo->ecc_strength = round_up(chip->ecc_strength_ds, 2);
 	if (!gpmi_check_ecc(this))
-		return false;
+		return -EINVAL;
 
 	/* Keep the C >= O */
 	if (geo->ecc_chunk_size < mtd->oobsize) {
 		dev_err(this->dev,
 			"unsupported nand chip. ecc size: %d, oob size : %d\n",
 			chip->ecc_step_ds, mtd->oobsize);
-		return false;
+		return -EINVAL;
 	}
 
 	/* The default value, see comment in the legacy_set_geometry(). */
@@ -242,7 +242,7 @@
 				+ ALIGN(geo->ecc_chunk_count, 4);
 
 	if (!this->swap_block_mark)
-		return true;
+		return 0;
 
 	/* For bit swap. */
 	block_mark_bit_offset = mtd->writesize * 8 -
@@ -251,7 +251,7 @@
 
 	geo->block_mark_byte_offset = block_mark_bit_offset / 8;
 	geo->block_mark_bit_offset  = block_mark_bit_offset % 8;
-	return true;
+	return 0;
 }
 
 static int legacy_set_geometry(struct gpmi_nand_data *this)
@@ -285,7 +285,8 @@
 	geo->ecc_strength = get_ecc_strength(this);
 	if (!gpmi_check_ecc(this)) {
 		dev_err(this->dev,
-			"required ecc strength of the NAND chip: %d is not supported by the GPMI controller (%d)\n",
+			"ecc strength: %d cannot be supported by the controller (%d)\n"
+			"try to use minimum ecc strength that NAND chip required\n",
 			geo->ecc_strength,
 			this->devdata->bch_max_ecc_strength);
 		return -EINVAL;
@@ -366,10 +367,11 @@
 
 int common_nfc_set_geometry(struct gpmi_nand_data *this)
 {
-	if (of_property_read_bool(this->dev->of_node, "fsl,use-minimum-ecc")
-		&& set_geometry_by_ecc_info(this))
-		return 0;
-	return legacy_set_geometry(this);
+	if ((of_property_read_bool(this->dev->of_node, "fsl,use-minimum-ecc"))
+				|| legacy_set_geometry(this))
+		return set_geometry_by_ecc_info(this);
+
+	return 0;
 }
 
 struct dma_chan *get_dma_chan(struct gpmi_nand_data *this)
@@ -2033,9 +2035,54 @@
 	return 0;
 }
 
+#ifdef CONFIG_PM_SLEEP
+static int gpmi_pm_suspend(struct device *dev)
+{
+	struct gpmi_nand_data *this = dev_get_drvdata(dev);
+
+	release_dma_channels(this);
+	return 0;
+}
+
+static int gpmi_pm_resume(struct device *dev)
+{
+	struct gpmi_nand_data *this = dev_get_drvdata(dev);
+	int ret;
+
+	ret = acquire_dma_channels(this);
+	if (ret < 0)
+		return ret;
+
+	/* re-init the GPMI registers */
+	this->flags &= ~GPMI_TIMING_INIT_OK;
+	ret = gpmi_init(this);
+	if (ret) {
+		dev_err(this->dev, "Error setting GPMI : %d\n", ret);
+		return ret;
+	}
+
+	/* re-init the BCH registers */
+	ret = bch_set_geometry(this);
+	if (ret) {
+		dev_err(this->dev, "Error setting BCH : %d\n", ret);
+		return ret;
+	}
+
+	/* re-init others */
+	gpmi_extra_init(this);
+
+	return 0;
+}
+#endif /* CONFIG_PM_SLEEP */
+
+static const struct dev_pm_ops gpmi_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(gpmi_pm_suspend, gpmi_pm_resume)
+};
+
 static struct platform_driver gpmi_nand_driver = {
 	.driver = {
 		.name = "gpmi-nand",
+		.pm = &gpmi_pm_ops,
 		.of_match_table = gpmi_nand_id_table,
 	},
 	.probe   = gpmi_nand_probe,
diff --git a/drivers/mtd/nand/mpc5121_nfc.c b/drivers/mtd/nand/mpc5121_nfc.c
index 6b93e89..5d7843f 100644
--- a/drivers/mtd/nand/mpc5121_nfc.c
+++ b/drivers/mtd/nand/mpc5121_nfc.c
@@ -626,7 +626,7 @@
 
 static int mpc5121_nfc_probe(struct platform_device *op)
 {
-	struct device_node *rootnode, *dn = op->dev.of_node;
+	struct device_node *dn = op->dev.of_node;
 	struct clk *clk;
 	struct device *dev = &op->dev;
 	struct mpc5121_nfc_prv *prv;
@@ -712,18 +712,15 @@
 	chip->ecc.mode = NAND_ECC_SOFT;
 
 	/* Support external chip-select logic on ADS5121 board */
-	rootnode = of_find_node_by_path("/");
-	if (of_device_is_compatible(rootnode, "fsl,mpc5121ads")) {
+	if (of_machine_is_compatible("fsl,mpc5121ads")) {
 		retval = ads5121_chipselect_init(mtd);
 		if (retval) {
 			dev_err(dev, "Chipselect init error!\n");
-			of_node_put(rootnode);
 			return retval;
 		}
 
 		chip->select_chip = ads5121_select_chip;
 	}
-	of_node_put(rootnode);
 
 	/* Enable NFC clock */
 	clk = devm_clk_get(dev, "ipg");
diff --git a/drivers/mtd/nand/nand_bbt.c b/drivers/mtd/nand/nand_bbt.c
index 4b6a708..2fbb523 100644
--- a/drivers/mtd/nand/nand_bbt.c
+++ b/drivers/mtd/nand/nand_bbt.c
@@ -1373,5 +1373,3 @@
 
 	return ret;
 }
-
-EXPORT_SYMBOL(nand_scan_bbt);
diff --git a/drivers/mtd/nand/nand_ids.c b/drivers/mtd/nand/nand_ids.c
index a8804a3..ccc05f5 100644
--- a/drivers/mtd/nand/nand_ids.c
+++ b/drivers/mtd/nand/nand_ids.c
@@ -50,8 +50,8 @@
 		  SZ_16K, SZ_8K, SZ_4M, 0, 6, 1280, NAND_ECC_INFO(40, SZ_1K) },
 	{"H27UCG8T2ATR-BC 64G 3.3V 8-bit",
 		{ .id = {0xad, 0xde, 0x94, 0xda, 0x74, 0xc4} },
-		  SZ_8K, SZ_8K, SZ_2M, 0, 6, 640, NAND_ECC_INFO(40, SZ_1K),
-		  4 },
+		  SZ_8K, SZ_8K, SZ_2M, NAND_NEED_SCRAMBLING, 6, 640,
+		  NAND_ECC_INFO(40, SZ_1K), 4 },
 
 	LEGACY_ID_NAND("NAND 4MiB 5V 8-bit",   0x6B, 4, SZ_8K, SP_OPTIONS),
 	LEGACY_ID_NAND("NAND 4MiB 3,3V 8-bit", 0xE3, 4, SZ_8K, SP_OPTIONS),
diff --git a/drivers/mtd/nand/nuc900_nand.c b/drivers/mtd/nand/nuc900_nand.c
index 220ddfc..dbc5b57 100644
--- a/drivers/mtd/nand/nuc900_nand.c
+++ b/drivers/mtd/nand/nuc900_nand.c
@@ -113,7 +113,7 @@
 {
 	unsigned int val;
 	spin_lock(&nand->lock);
-	val = __raw_readl(REG_SMISR);
+	val = __raw_readl(nand->reg + REG_SMISR);
 	val &= READYBUSY;
 	spin_unlock(&nand->lock);
 
diff --git a/drivers/mtd/nand/sunxi_nand.c b/drivers/mtd/nand/sunxi_nand.c
index 51e10a3..b5ea6b3 100644
--- a/drivers/mtd/nand/sunxi_nand.c
+++ b/drivers/mtd/nand/sunxi_nand.c
@@ -60,6 +60,7 @@
 #define NFC_REG_ECC_ERR_CNT(x)	((0x0040 + (x)) & ~0x3)
 #define NFC_REG_USER_DATA(x)	(0x0050 + ((x) * 4))
 #define NFC_REG_SPARE_AREA	0x00A0
+#define NFC_REG_PAT_ID		0x00A4
 #define NFC_RAM0_BASE		0x0400
 #define NFC_RAM1_BASE		0x0800
 
@@ -538,6 +539,174 @@
 	sunxi_nfc_wait_int(nfc, NFC_CMD_INT_FLAG, 0);
 }
 
+/* These seed values have been extracted from Allwinner's BSP */
+static const u16 sunxi_nfc_randomizer_page_seeds[] = {
+	0x2b75, 0x0bd0, 0x5ca3, 0x62d1, 0x1c93, 0x07e9, 0x2162, 0x3a72,
+	0x0d67, 0x67f9, 0x1be7, 0x077d, 0x032f, 0x0dac, 0x2716, 0x2436,
+	0x7922, 0x1510, 0x3860, 0x5287, 0x480f, 0x4252, 0x1789, 0x5a2d,
+	0x2a49, 0x5e10, 0x437f, 0x4b4e, 0x2f45, 0x216e, 0x5cb7, 0x7130,
+	0x2a3f, 0x60e4, 0x4dc9, 0x0ef0, 0x0f52, 0x1bb9, 0x6211, 0x7a56,
+	0x226d, 0x4ea7, 0x6f36, 0x3692, 0x38bf, 0x0c62, 0x05eb, 0x4c55,
+	0x60f4, 0x728c, 0x3b6f, 0x2037, 0x7f69, 0x0936, 0x651a, 0x4ceb,
+	0x6218, 0x79f3, 0x383f, 0x18d9, 0x4f05, 0x5c82, 0x2912, 0x6f17,
+	0x6856, 0x5938, 0x1007, 0x61ab, 0x3e7f, 0x57c2, 0x542f, 0x4f62,
+	0x7454, 0x2eac, 0x7739, 0x42d4, 0x2f90, 0x435a, 0x2e52, 0x2064,
+	0x637c, 0x66ad, 0x2c90, 0x0bad, 0x759c, 0x0029, 0x0986, 0x7126,
+	0x1ca7, 0x1605, 0x386a, 0x27f5, 0x1380, 0x6d75, 0x24c3, 0x0f8e,
+	0x2b7a, 0x1418, 0x1fd1, 0x7dc1, 0x2d8e, 0x43af, 0x2267, 0x7da3,
+	0x4e3d, 0x1338, 0x50db, 0x454d, 0x764d, 0x40a3, 0x42e6, 0x262b,
+	0x2d2e, 0x1aea, 0x2e17, 0x173d, 0x3a6e, 0x71bf, 0x25f9, 0x0a5d,
+	0x7c57, 0x0fbe, 0x46ce, 0x4939, 0x6b17, 0x37bb, 0x3e91, 0x76db,
+};
+
+/*
+ * sunxi_nfc_randomizer_ecc512_seeds and sunxi_nfc_randomizer_ecc1024_seeds
+ * have been generated using
+ * sunxi_nfc_randomizer_step(seed, (step_size * 8) + 15), which is what
+ * the randomizer engine does internally before de/scrambling OOB data.
+ *
+ * Those tables are statically defined to avoid calculating randomizer state
+ * at runtime.
+ */
+static const u16 sunxi_nfc_randomizer_ecc512_seeds[] = {
+	0x3346, 0x367f, 0x1f18, 0x769a, 0x4f64, 0x068c, 0x2ef1, 0x6b64,
+	0x28a9, 0x15d7, 0x30f8, 0x3659, 0x53db, 0x7c5f, 0x71d4, 0x4409,
+	0x26eb, 0x03cc, 0x655d, 0x47d4, 0x4daa, 0x0877, 0x712d, 0x3617,
+	0x3264, 0x49aa, 0x7f9e, 0x588e, 0x4fbc, 0x7176, 0x7f91, 0x6c6d,
+	0x4b95, 0x5fb7, 0x3844, 0x4037, 0x0184, 0x081b, 0x0ee8, 0x5b91,
+	0x293d, 0x1f71, 0x0e6f, 0x402b, 0x5122, 0x1e52, 0x22be, 0x3d2d,
+	0x75bc, 0x7c60, 0x6291, 0x1a2f, 0x61d4, 0x74aa, 0x4140, 0x29ab,
+	0x472d, 0x2852, 0x017e, 0x15e8, 0x5ec2, 0x17cf, 0x7d0f, 0x06b8,
+	0x117a, 0x6b94, 0x789b, 0x3126, 0x6ac5, 0x5be7, 0x150f, 0x51f8,
+	0x7889, 0x0aa5, 0x663d, 0x77e8, 0x0b87, 0x3dcb, 0x360d, 0x218b,
+	0x512f, 0x7dc9, 0x6a4d, 0x630a, 0x3547, 0x1dd2, 0x5aea, 0x69a5,
+	0x7bfa, 0x5e4f, 0x1519, 0x6430, 0x3a0e, 0x5eb3, 0x5425, 0x0c7a,
+	0x5540, 0x3670, 0x63c1, 0x31e9, 0x5a39, 0x2de7, 0x5979, 0x2891,
+	0x1562, 0x014b, 0x5b05, 0x2756, 0x5a34, 0x13aa, 0x6cb5, 0x2c36,
+	0x5e72, 0x1306, 0x0861, 0x15ef, 0x1ee8, 0x5a37, 0x7ac4, 0x45dd,
+	0x44c4, 0x7266, 0x2f41, 0x3ccc, 0x045e, 0x7d40, 0x7c66, 0x0fa0,
+};
+
+static const u16 sunxi_nfc_randomizer_ecc1024_seeds[] = {
+	0x2cf5, 0x35f1, 0x63a4, 0x5274, 0x2bd2, 0x778b, 0x7285, 0x32b6,
+	0x6a5c, 0x70d6, 0x757d, 0x6769, 0x5375, 0x1e81, 0x0cf3, 0x3982,
+	0x6787, 0x042a, 0x6c49, 0x1925, 0x56a8, 0x40a9, 0x063e, 0x7bd9,
+	0x4dbf, 0x55ec, 0x672e, 0x7334, 0x5185, 0x4d00, 0x232a, 0x7e07,
+	0x445d, 0x6b92, 0x528f, 0x4255, 0x53ba, 0x7d82, 0x2a2e, 0x3a4e,
+	0x75eb, 0x450c, 0x6844, 0x1b5d, 0x581a, 0x4cc6, 0x0379, 0x37b2,
+	0x419f, 0x0e92, 0x6b27, 0x5624, 0x01e3, 0x07c1, 0x44a5, 0x130c,
+	0x13e8, 0x5910, 0x0876, 0x60c5, 0x54e3, 0x5b7f, 0x2269, 0x509f,
+	0x7665, 0x36fd, 0x3e9a, 0x0579, 0x6295, 0x14ef, 0x0a81, 0x1bcc,
+	0x4b16, 0x64db, 0x0514, 0x4f07, 0x0591, 0x3576, 0x6853, 0x0d9e,
+	0x259f, 0x38b7, 0x64fb, 0x3094, 0x4693, 0x6ddd, 0x29bb, 0x0bc8,
+	0x3f47, 0x490e, 0x0c0e, 0x7933, 0x3c9e, 0x5840, 0x398d, 0x3e68,
+	0x4af1, 0x71f5, 0x57cf, 0x1121, 0x64eb, 0x3579, 0x15ac, 0x584d,
+	0x5f2a, 0x47e2, 0x6528, 0x6eac, 0x196e, 0x6b96, 0x0450, 0x0179,
+	0x609c, 0x06e1, 0x4626, 0x42c7, 0x273e, 0x486f, 0x0705, 0x1601,
+	0x145b, 0x407e, 0x062b, 0x57a5, 0x53f9, 0x5659, 0x4410, 0x3ccd,
+};
+
+static u16 sunxi_nfc_randomizer_step(u16 state, int count)
+{
+	state &= 0x7fff;
+
+	/*
+	 * This loop is just a simple implementation of a Fibonacci LFSR using
+	 * the x16 + x15 + 1 polynomial.
+	 */
+	while (count--)
+		state = ((state >> 1) |
+			 (((state ^ (state >> 1)) & 1) << 14)) & 0x7fff;
+
+	return state;
+}
+
+static u16 sunxi_nfc_randomizer_state(struct mtd_info *mtd, int page, bool ecc)
+{
+	const u16 *seeds = sunxi_nfc_randomizer_page_seeds;
+	int mod = mtd_div_by_ws(mtd->erasesize, mtd);
+
+	if (mod > ARRAY_SIZE(sunxi_nfc_randomizer_page_seeds))
+		mod = ARRAY_SIZE(sunxi_nfc_randomizer_page_seeds);
+
+	if (ecc) {
+		if (mtd->ecc_step_size == 512)
+			seeds = sunxi_nfc_randomizer_ecc512_seeds;
+		else
+			seeds = sunxi_nfc_randomizer_ecc1024_seeds;
+	}
+
+	return seeds[page % mod];
+}
+
+static void sunxi_nfc_randomizer_config(struct mtd_info *mtd,
+					int page, bool ecc)
+{
+	struct nand_chip *nand = mtd->priv;
+	struct sunxi_nfc *nfc = to_sunxi_nfc(nand->controller);
+	u32 ecc_ctl = readl(nfc->regs + NFC_REG_ECC_CTL);
+	u16 state;
+
+	if (!(nand->options & NAND_NEED_SCRAMBLING))
+		return;
+
+	ecc_ctl = readl(nfc->regs + NFC_REG_ECC_CTL);
+	state = sunxi_nfc_randomizer_state(mtd, page, ecc);
+	ecc_ctl = readl(nfc->regs + NFC_REG_ECC_CTL) & ~NFC_RANDOM_SEED_MSK;
+	writel(ecc_ctl | NFC_RANDOM_SEED(state), nfc->regs + NFC_REG_ECC_CTL);
+}
+
+static void sunxi_nfc_randomizer_enable(struct mtd_info *mtd)
+{
+	struct nand_chip *nand = mtd->priv;
+	struct sunxi_nfc *nfc = to_sunxi_nfc(nand->controller);
+
+	if (!(nand->options & NAND_NEED_SCRAMBLING))
+		return;
+
+	writel(readl(nfc->regs + NFC_REG_ECC_CTL) | NFC_RANDOM_EN,
+	       nfc->regs + NFC_REG_ECC_CTL);
+}
+
+static void sunxi_nfc_randomizer_disable(struct mtd_info *mtd)
+{
+	struct nand_chip *nand = mtd->priv;
+	struct sunxi_nfc *nfc = to_sunxi_nfc(nand->controller);
+
+	if (!(nand->options & NAND_NEED_SCRAMBLING))
+		return;
+
+	writel(readl(nfc->regs + NFC_REG_ECC_CTL) & ~NFC_RANDOM_EN,
+	       nfc->regs + NFC_REG_ECC_CTL);
+}
+
+static void sunxi_nfc_randomize_bbm(struct mtd_info *mtd, int page, u8 *bbm)
+{
+	u16 state = sunxi_nfc_randomizer_state(mtd, page, true);
+
+	bbm[0] ^= state;
+	bbm[1] ^= sunxi_nfc_randomizer_step(state, 8);
+}
+
+static void sunxi_nfc_randomizer_write_buf(struct mtd_info *mtd,
+					   const uint8_t *buf, int len,
+					   bool ecc, int page)
+{
+	sunxi_nfc_randomizer_config(mtd, page, ecc);
+	sunxi_nfc_randomizer_enable(mtd);
+	sunxi_nfc_write_buf(mtd, buf, len);
+	sunxi_nfc_randomizer_disable(mtd);
+}
+
+static void sunxi_nfc_randomizer_read_buf(struct mtd_info *mtd, uint8_t *buf,
+					  int len, bool ecc, int page)
+{
+	sunxi_nfc_randomizer_config(mtd, page, ecc);
+	sunxi_nfc_randomizer_enable(mtd);
+	sunxi_nfc_read_buf(mtd, buf, len);
+	sunxi_nfc_randomizer_disable(mtd);
+}
+
 static void sunxi_nfc_hw_ecc_enable(struct mtd_info *mtd)
 {
 	struct nand_chip *nand = mtd_to_nand(mtd);
@@ -574,18 +743,20 @@
 				       u8 *data, int data_off,
 				       u8 *oob, int oob_off,
 				       int *cur_off,
-				       unsigned int *max_bitflips)
+				       unsigned int *max_bitflips,
+				       bool bbm, int page)
 {
 	struct nand_chip *nand = mtd_to_nand(mtd);
 	struct sunxi_nfc *nfc = to_sunxi_nfc(nand->controller);
 	struct nand_ecc_ctrl *ecc = &nand->ecc;
+	int raw_mode = 0;
 	u32 status;
 	int ret;
 
 	if (*cur_off != data_off)
 		nand->cmdfunc(mtd, NAND_CMD_RNDOUT, data_off, -1);
 
-	sunxi_nfc_read_buf(mtd, NULL, ecc->size);
+	sunxi_nfc_randomizer_read_buf(mtd, NULL, ecc->size, false, page);
 
 	if (data_off + ecc->size != oob_off)
 		nand->cmdfunc(mtd, NAND_CMD_RNDOUT, oob_off, -1);
@@ -594,25 +765,54 @@
 	if (ret)
 		return ret;
 
+	sunxi_nfc_randomizer_enable(mtd);
 	writel(NFC_DATA_TRANS | NFC_DATA_SWAP_METHOD | NFC_ECC_OP,
 	       nfc->regs + NFC_REG_CMD);
 
 	ret = sunxi_nfc_wait_int(nfc, NFC_CMD_INT_FLAG, 0);
+	sunxi_nfc_randomizer_disable(mtd);
 	if (ret)
 		return ret;
 
+	*cur_off = oob_off + ecc->bytes + 4;
+
 	status = readl(nfc->regs + NFC_REG_ECC_ST);
+	if (status & NFC_ECC_PAT_FOUND(0)) {
+		u8 pattern = 0xff;
+
+		if (unlikely(!(readl(nfc->regs + NFC_REG_PAT_ID) & 0x1)))
+			pattern = 0x0;
+
+		memset(data, pattern, ecc->size);
+		memset(oob, pattern, ecc->bytes + 4);
+
+		return 1;
+	}
+
 	ret = NFC_ECC_ERR_CNT(0, readl(nfc->regs + NFC_REG_ECC_ERR_CNT(0)));
 
 	memcpy_fromio(data, nfc->regs + NFC_RAM0_BASE, ecc->size);
 
 	nand->cmdfunc(mtd, NAND_CMD_RNDOUT, oob_off, -1);
-	sunxi_nfc_read_buf(mtd, oob, ecc->bytes + 4);
+	sunxi_nfc_randomizer_read_buf(mtd, oob, ecc->bytes + 4, true, page);
 
 	if (status & NFC_ECC_ERR(0)) {
+		/*
+		 * Re-read the data with the randomizer disabled to identify
+		 * bitflips in erased pages.
+		 */
+		if (nand->options & NAND_NEED_SCRAMBLING) {
+			nand->cmdfunc(mtd, NAND_CMD_RNDOUT, data_off, -1);
+			nand->read_buf(mtd, data, ecc->size);
+			nand->cmdfunc(mtd, NAND_CMD_RNDOUT, oob_off, -1);
+			nand->read_buf(mtd, oob, ecc->bytes + 4);
+		}
+
 		ret = nand_check_erased_ecc_chunk(data,	ecc->size,
 						  oob, ecc->bytes + 4,
 						  NULL, 0, ecc->strength);
+		if (ret >= 0)
+			raw_mode = 1;
 	} else {
 		/*
 		 * The engine protects 4 bytes of OOB data per chunk.
@@ -620,6 +820,10 @@
 		 */
 		sunxi_nfc_user_data_to_buf(readl(nfc->regs + NFC_REG_USER_DATA(0)),
 					   oob);
+
+		/* De-randomize the Bad Block Marker. */
+		if (bbm && nand->options & NAND_NEED_SCRAMBLING)
+			sunxi_nfc_randomize_bbm(mtd, page, oob);
 	}
 
 	if (ret < 0) {
@@ -629,13 +833,12 @@
 		*max_bitflips = max_t(unsigned int, *max_bitflips, ret);
 	}
 
-	*cur_off = oob_off + ecc->bytes + 4;
-
-	return 0;
+	return raw_mode;
 }
 
 static void sunxi_nfc_hw_ecc_read_extra_oob(struct mtd_info *mtd,
-					    u8 *oob, int *cur_off)
+					    u8 *oob, int *cur_off,
+					    bool randomize, int page)
 {
 	struct nand_chip *nand = mtd_to_nand(mtd);
 	struct nand_ecc_ctrl *ecc = &nand->ecc;
@@ -649,7 +852,11 @@
 		nand->cmdfunc(mtd, NAND_CMD_RNDOUT,
 			      offset + mtd->writesize, -1);
 
-	sunxi_nfc_read_buf(mtd, oob + offset, len);
+	if (!randomize)
+		sunxi_nfc_read_buf(mtd, oob + offset, len);
+	else
+		sunxi_nfc_randomizer_read_buf(mtd, oob + offset, len,
+					      false, page);
 
 	*cur_off = mtd->oobsize + mtd->writesize;
 }
@@ -662,7 +869,8 @@
 static int sunxi_nfc_hw_ecc_write_chunk(struct mtd_info *mtd,
 					const u8 *data, int data_off,
 					const u8 *oob, int oob_off,
-					int *cur_off)
+					int *cur_off, bool bbm,
+					int page)
 {
 	struct nand_chip *nand = mtd_to_nand(mtd);
 	struct sunxi_nfc *nfc = to_sunxi_nfc(nand->controller);
@@ -672,11 +880,20 @@
 	if (data_off != *cur_off)
 		nand->cmdfunc(mtd, NAND_CMD_RNDIN, data_off, -1);
 
-	sunxi_nfc_write_buf(mtd, data, ecc->size);
+	sunxi_nfc_randomizer_write_buf(mtd, data, ecc->size, false, page);
 
 	/* Fill OOB data in */
-	writel(sunxi_nfc_buf_to_user_data(oob),
-	       nfc->regs + NFC_REG_USER_DATA(0));
+	if ((nand->options & NAND_NEED_SCRAMBLING) && bbm) {
+		u8 user_data[4];
+
+		memcpy(user_data, oob, 4);
+		sunxi_nfc_randomize_bbm(mtd, page, user_data);
+		writel(sunxi_nfc_buf_to_user_data(user_data),
+		       nfc->regs + NFC_REG_USER_DATA(0));
+	} else {
+		writel(sunxi_nfc_buf_to_user_data(oob),
+		       nfc->regs + NFC_REG_USER_DATA(0));
+	}
 
 	if (data_off + ecc->size != oob_off)
 		nand->cmdfunc(mtd, NAND_CMD_RNDIN, oob_off, -1);
@@ -685,11 +902,13 @@
 	if (ret)
 		return ret;
 
+	sunxi_nfc_randomizer_enable(mtd);
 	writel(NFC_DATA_TRANS | NFC_DATA_SWAP_METHOD |
 	       NFC_ACCESS_DIR | NFC_ECC_OP,
 	       nfc->regs + NFC_REG_CMD);
 
 	ret = sunxi_nfc_wait_int(nfc, NFC_CMD_INT_FLAG, 0);
+	sunxi_nfc_randomizer_disable(mtd);
 	if (ret)
 		return ret;
 
@@ -699,7 +918,8 @@
 }
 
 static void sunxi_nfc_hw_ecc_write_extra_oob(struct mtd_info *mtd,
-					     u8 *oob, int *cur_off)
+					     u8 *oob, int *cur_off,
+					     int page)
 {
 	struct nand_chip *nand = mtd_to_nand(mtd);
 	struct nand_ecc_ctrl *ecc = &nand->ecc;
@@ -713,7 +933,7 @@
 		nand->cmdfunc(mtd, NAND_CMD_RNDIN,
 			      offset + mtd->writesize, -1);
 
-	sunxi_nfc_write_buf(mtd, oob + offset, len);
+	sunxi_nfc_randomizer_write_buf(mtd, oob + offset, len, false, page);
 
 	*cur_off = mtd->oobsize + mtd->writesize;
 }
@@ -725,6 +945,7 @@
 	struct nand_ecc_ctrl *ecc = &chip->ecc;
 	unsigned int max_bitflips = 0;
 	int ret, i, cur_off = 0;
+	bool raw_mode = false;
 
 	sunxi_nfc_hw_ecc_enable(mtd);
 
@@ -736,13 +957,17 @@
 
 		ret = sunxi_nfc_hw_ecc_read_chunk(mtd, data, data_off, oob,
 						  oob_off + mtd->writesize,
-						  &cur_off, &max_bitflips);
-		if (ret)
+						  &cur_off, &max_bitflips,
+						  !i, page);
+		if (ret < 0)
 			return ret;
+		else if (ret)
+			raw_mode = true;
 	}
 
 	if (oob_required)
-		sunxi_nfc_hw_ecc_read_extra_oob(mtd, chip->oob_poi, &cur_off);
+		sunxi_nfc_hw_ecc_read_extra_oob(mtd, chip->oob_poi, &cur_off,
+						!raw_mode, page);
 
 	sunxi_nfc_hw_ecc_disable(mtd);
 
@@ -767,13 +992,14 @@
 
 		ret = sunxi_nfc_hw_ecc_write_chunk(mtd, data, data_off, oob,
 						   oob_off + mtd->writesize,
-						   &cur_off);
+						   &cur_off, !i, page);
 		if (ret)
 			return ret;
 	}
 
-	if (oob_required)
-		sunxi_nfc_hw_ecc_write_extra_oob(mtd, chip->oob_poi, &cur_off);
+	if (oob_required || (chip->options & NAND_NEED_SCRAMBLING))
+		sunxi_nfc_hw_ecc_write_extra_oob(mtd, chip->oob_poi,
+						 &cur_off, page);
 
 	sunxi_nfc_hw_ecc_disable(mtd);
 
@@ -788,6 +1014,7 @@
 	struct nand_ecc_ctrl *ecc = &chip->ecc;
 	unsigned int max_bitflips = 0;
 	int ret, i, cur_off = 0;
+	bool raw_mode = false;
 
 	sunxi_nfc_hw_ecc_enable(mtd);
 
@@ -799,13 +1026,16 @@
 
 		ret = sunxi_nfc_hw_ecc_read_chunk(mtd, data, data_off, oob,
 						  oob_off, &cur_off,
-						  &max_bitflips);
-		if (ret)
+						  &max_bitflips, !i, page);
+		if (ret < 0)
 			return ret;
+		else if (ret)
+			raw_mode = true;
 	}
 
 	if (oob_required)
-		sunxi_nfc_hw_ecc_read_extra_oob(mtd, chip->oob_poi, &cur_off);
+		sunxi_nfc_hw_ecc_read_extra_oob(mtd, chip->oob_poi, &cur_off,
+						!raw_mode, page);
 
 	sunxi_nfc_hw_ecc_disable(mtd);
 
@@ -829,13 +1059,15 @@
 		const u8 *oob = chip->oob_poi + (i * (ecc->bytes + 4));
 
 		ret = sunxi_nfc_hw_ecc_write_chunk(mtd, data, data_off,
-						   oob, oob_off, &cur_off);
+						   oob, oob_off, &cur_off,
+						   false, page);
 		if (ret)
 			return ret;
 	}
 
-	if (oob_required)
-		sunxi_nfc_hw_ecc_write_extra_oob(mtd, chip->oob_poi, &cur_off);
+	if (oob_required || (chip->options & NAND_NEED_SCRAMBLING))
+		sunxi_nfc_hw_ecc_write_extra_oob(mtd, chip->oob_poi,
+						 &cur_off, page);
 
 	sunxi_nfc_hw_ecc_disable(mtd);
 
@@ -1345,6 +1577,9 @@
 	if (nand->bbt_options & NAND_BBT_USE_FLASH)
 		nand->bbt_options |= NAND_BBT_NO_OOB;
 
+	if (nand->options & NAND_NEED_SCRAMBLING)
+		nand->options |= NAND_NO_SUBPAGE_WRITE;
+
 	ret = sunxi_nand_chip_init_timings(chip, np);
 	if (ret) {
 		dev_err(dev, "could not configure chip timings: %d\n", ret);
diff --git a/drivers/mtd/onenand/onenand_bbt.c b/drivers/mtd/onenand/onenand_bbt.c
index 08d0085..680188a 100644
--- a/drivers/mtd/onenand/onenand_bbt.c
+++ b/drivers/mtd/onenand/onenand_bbt.c
@@ -179,7 +179,7 @@
  * by the onenand_release function.
  *
  */
-int onenand_scan_bbt(struct mtd_info *mtd, struct nand_bbt_descr *bd)
+static int onenand_scan_bbt(struct mtd_info *mtd, struct nand_bbt_descr *bd)
 {
 	struct onenand_chip *this = mtd->priv;
 	struct bbm_info *bbm = this->bbm;
@@ -247,6 +247,3 @@
 
 	return onenand_scan_bbt(mtd, bbm->badblock_pattern);
 }
-
-EXPORT_SYMBOL(onenand_scan_bbt);
-EXPORT_SYMBOL(onenand_default_bbt);
diff --git a/drivers/mtd/spi-nor/mtk-quadspi.c b/drivers/mtd/spi-nor/mtk-quadspi.c
index d5f850d..8bed1a4c 100644
--- a/drivers/mtd/spi-nor/mtk-quadspi.c
+++ b/drivers/mtd/spi-nor/mtk-quadspi.c
@@ -371,8 +371,8 @@
 	return ret;
 }
 
-static int __init mtk_nor_init(struct mt8173_nor *mt8173_nor,
-			       struct device_node *flash_node)
+static int mtk_nor_init(struct mt8173_nor *mt8173_nor,
+			struct device_node *flash_node)
 {
 	int ret;
 	struct spi_nor *nor;
diff --git a/include/linux/mtd/bbm.h b/include/linux/mtd/bbm.h
index 36bb6a5..3bf8f954 100644
--- a/include/linux/mtd/bbm.h
+++ b/include/linux/mtd/bbm.h
@@ -166,7 +166,6 @@
 };
 
 /* OneNAND BBT interface */
-extern int onenand_scan_bbt(struct mtd_info *mtd, struct nand_bbt_descr *bd);
 extern int onenand_default_bbt(struct mtd_info *mtd);
 
 #endif	/* __LINUX_MTD_BBM_H */
diff --git a/include/linux/mtd/nand.h b/include/linux/mtd/nand.h
index bdd68e2..a13dfd5 100644
--- a/include/linux/mtd/nand.h
+++ b/include/linux/mtd/nand.h
@@ -168,6 +168,12 @@
 /* Device supports subpage reads */
 #define NAND_SUBPAGE_READ	0x00001000
 
+/*
+ * Some MLC NANDs need data scrambling to limit bitflips caused by repeated
+ * patterns.
+ */
+#define NAND_NEED_SCRAMBLING	0x00002000
+
 /* Options valid for Samsung large page devices */
 #define NAND_SAMSUNG_LP_OPTIONS NAND_CACHEPRG