mtd: nand: raw: gpmi: new bch geometry settings

1/2

---
 drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c | 262 ++++++++++++++++++---
 drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.h |  12 +-
 2 files changed, 231 insertions(+), 43 deletions(-)
index 4d08e4ab5c1b..bb061205679d 100644
@@ -218,7 +218,8 @@ static void gpmi_dump_info(struct gpmi_nand_data *this)
 		"ECC Strength           : %u\n"
 		"Page Size in Bytes     : %u\n"
 		"Metadata Size in Bytes : %u\n"
-		"ECC Chunk Size in Bytes: %u\n"
+		"ECC Chunk0 Size in Bytes: %u\n"
+		"ECC Chunkn Size in Bytes: %u\n"
 		"ECC Chunk Count        : %u\n"
 		"Payload Size in Bytes  : %u\n"
 		"Auxiliary Size in Bytes: %u\n"

@@ -229,7 +230,8 @@ static void gpmi_dump_info(struct gpmi_nand_data *this)
 		geo->ecc_strength,
 		geo->page_size,
 		geo->metadata_size,
-		geo->ecc_chunk_size,
+		geo->ecc_chunk0_size,
+		geo->ecc_chunkn_size,
 		geo->ecc_chunk_count,
 		geo->payload_size,
 		geo->auxiliary_size,

@@ -251,6 +253,37 @@ static inline bool gpmi_check_ecc(struct gpmi_nand_data *this)
 	return geo->ecc_strength <= this->devdata->bch_max_ecc_strength;
 }
 
+static inline bool bbm_in_data_chunk(struct gpmi_nand_data *this,
+			unsigned int *chunk_num)
+{
+	struct bch_geometry *geo = &this->bch_geometry;
+	struct nand_chip *chip = &this->nand;
+	struct mtd_info *mtd = nand_to_mtd(chip);
+	unsigned int i, j;
+
+	if (geo->ecc_chunk0_size != geo->ecc_chunkn_size) {
+		dev_err(this->dev, "The size of chunk0 must equal to chunkn\n");
+		return false;
+	}
+
+	i = (mtd->writesize * 8 - geo->metadata_size * 8) /
+		(geo->gf_len * geo->ecc_strength +
+			geo->ecc_chunkn_size * 8);
+
+	j = (mtd->writesize * 8 - geo->metadata_size * 8) -
+		(geo->gf_len * geo->ecc_strength +
+			geo->ecc_chunkn_size * 8) * i;
+
+	if (j < geo->ecc_chunkn_size * 8) {
+		*chunk_num = i+1;
+		dev_dbg(this->dev, "Set ecc to %d and bbm in chunk %d\n",
+				geo->ecc_strength, *chunk_num);
+		return true;
+	}
+
+	return false;
+}
+
 /*
  * If we can get the ECC information from the nand chip, we do not
  * need to calculate them ourselves.

@@ -280,13 +313,14 @@ static int set_geometry_by_ecc_info(struct gpmi_nand_data *this,
 			nanddev_get_ecc_requirements(&chip->base)->step_size);
 		return -EINVAL;
 	}
-	geo->ecc_chunk_size = ecc_step;
+	geo->ecc_chunk0_size = ecc_step;
+	geo->ecc_chunkn_size = ecc_step;
 	geo->ecc_strength = round_up(ecc_strength, 2);
 	if (!gpmi_check_ecc(this))
 		return -EINVAL;
 
 	/* Keep the C >= O */
-	if (geo->ecc_chunk_size < mtd->oobsize) {
+	if (geo->ecc_chunkn_size < mtd->oobsize) {
 		dev_err(this->dev,
 			"unsupported nand chip. ecc size: %d, oob size : %d\n",
 			ecc_step, mtd->oobsize);

@@ -296,7 +330,7 @@ static int set_geometry_by_ecc_info(struct gpmi_nand_data *this,
 	/* The default value, see comment in the legacy_set_geometry(). */
 	geo->metadata_size = 10;
 
-	geo->ecc_chunk_count = mtd->writesize / geo->ecc_chunk_size;
+	geo->ecc_chunk_count = mtd->writesize / geo->ecc_chunkn_size;
 
 	/*
 	 * Now, the NAND chip with 2K page(data chunk is 512byte) shows below:

@@ -399,6 +433,132 @@ static inline int get_ecc_strength(struct gpmi_nand_data *this)
 	return round_down(ecc_strength, 2);
 }
 
+static int set_geometry_for_large_oob(struct gpmi_nand_data *this)
+{
+	struct bch_geometry *geo = &this->bch_geometry;
+	struct nand_chip *chip = &this->nand;
+	struct mtd_info *mtd = nand_to_mtd(chip);
+	const struct nand_ecc_props *requirements =
+		nanddev_get_ecc_requirements(&chip->base);
+	unsigned int block_mark_bit_offset;
+	unsigned int max_ecc;
+	unsigned int bbm_chunk;
+	unsigned int i;
+
+	/* sanity check for the minimum ecc nand required */
+	if (!(requirements->strength > 0 &&
+	      requirements->step_size > 0))
+		return -EINVAL;
+	geo->ecc_strength = requirements->strength;
+
+	/* check if platform can support this nand */
+	if (!gpmi_check_ecc(this)) {
+		dev_err(this->dev,
+			"unsupported NAND chip, minimum ecc required %d\n",
+			geo->ecc_strength);
+		return -EINVAL;
+	}
+
+	/* calculate the maximum ecc platform can support*/
+	geo->metadata_size = 10;
+	geo->gf_len = 14;
+	geo->ecc_chunk0_size = 1024;
+	geo->ecc_chunkn_size = 1024;
+	geo->ecc_chunk_count = mtd->writesize / geo->ecc_chunkn_size;
+	max_ecc = min(get_ecc_strength(this),
+		      this->devdata->bch_max_ecc_strength);
+
+	/* search a supported ecc strength that makes bbm */
+	/* located in data chunk  */
+	geo->ecc_strength = requirements->strength;
+	while (!(geo->ecc_strength > max_ecc)) {
+		if (bbm_in_data_chunk(this, &bbm_chunk))
+			goto geo_setting;
+		geo->ecc_strength += 2;
+	}
+
+	/* if none of them works, keep using the minimum ecc */
+	/* nand required but changing ecc page layout  */
+	geo->ecc_strength = requirements->strength;
+	/* add extra ecc for meta data */
+	geo->ecc_chunk0_size = 0;
+	geo->ecc_chunk_count = (mtd->writesize / geo->ecc_chunkn_size) + 1;
+	geo->ecc_for_meta = 1;
+	/* check if oob can afford this extra ecc chunk */
+	if (mtd->oobsize * 8 < geo->metadata_size * 8 +
+	    geo->gf_len * geo->ecc_strength * geo->ecc_chunk_count) {
+		dev_err(this->dev, "unsupported NAND chip with new layout\n");
+		return -EINVAL;
+	}
+
+	/* calculate in which chunk bbm located */
+	bbm_chunk = (mtd->writesize * 8 - geo->metadata_size * 8 -
+		     geo->gf_len * geo->ecc_strength) /
+		     (geo->gf_len * geo->ecc_strength +
+		     geo->ecc_chunkn_size * 8) + 1;
+
+geo_setting:
+
+	geo->page_size = mtd->writesize + geo->metadata_size +
+		(geo->gf_len * geo->ecc_strength * geo->ecc_chunk_count) / 8;
+	geo->payload_size = mtd->writesize;
+
+	/*
+	 * The auxiliary buffer contains the metadata and the ECC status. The
+	 * metadata is padded to the nearest 32-bit boundary. The ECC status
+	 * contains one byte for every ECC chunk, and is also padded to the
+	 * nearest 32-bit boundary.
+	 */
+	geo->auxiliary_status_offset = ALIGN(geo->metadata_size, 4);
+	geo->auxiliary_size = ALIGN(geo->metadata_size, 4)
+				    + ALIGN(geo->ecc_chunk_count, 4);
+
+	if (!this->swap_block_mark)
+		return 0;
+
+	/* calculate the number of ecc chunk behind the bbm */
+	i = (mtd->writesize / geo->ecc_chunkn_size) - bbm_chunk + 1;
+
+	block_mark_bit_offset = mtd->writesize * 8 -
+		(geo->ecc_strength * geo->gf_len * (geo->ecc_chunk_count - i)
+		+ geo->metadata_size * 8);
+
+	geo->block_mark_byte_offset = block_mark_bit_offset / 8;
+	geo->block_mark_bit_offset  = block_mark_bit_offset % 8;
+
+	dev_dbg(this->dev, "BCH Geometry :\n"
+		"GF length              : %u\n"
+		"ECC Strength           : %u\n"
+		"Page Size in Bytes     : %u\n"
+		"Metadata Size in Bytes : %u\n"
+		"ECC Chunk0 Size in Bytes: %u\n"
+		"ECC Chunkn Size in Bytes: %u\n"
+		"ECC Chunk Count        : %u\n"
+		"Payload Size in Bytes  : %u\n"
+		"Auxiliary Size in Bytes: %u\n"
+		"Auxiliary Status Offset: %u\n"
+		"Block Mark Byte Offset : %u\n"
+		"Block Mark Bit Offset  : %u\n"
+		"Block Mark in chunk	: %u\n"
+		"Ecc for Meta data	: %u\n",
+		geo->gf_len,
+		geo->ecc_strength,
+		geo->page_size,
+		geo->metadata_size,
+		geo->ecc_chunk0_size,
+		geo->ecc_chunkn_size,
+		geo->ecc_chunk_count,
+		geo->payload_size,
+		geo->auxiliary_size,
+		geo->auxiliary_status_offset,
+		geo->block_mark_byte_offset,
+		geo->block_mark_bit_offset,
+		bbm_chunk,
+		geo->ecc_for_meta);
+
+	return 0;
+}
+
 static int legacy_set_geometry(struct gpmi_nand_data *this)
 {
 	struct bch_geometry *geo = &this->bch_geometry;

@@ -407,6 +567,7 @@ static int legacy_set_geometry(struct gpmi_nand_data *this)
 	unsigned int status_size;
 	unsigned int block_mark_bit_offset;
 
+	dev_warn(this->dev, "use legacy bch geometry\n");
 	/*
 	 * The size of the metadata can be changed, though we set it to 10
 	 * bytes now. But it can't be too large, because we have to save

@@ -418,13 +579,15 @@ static int legacy_set_geometry(struct gpmi_nand_data *this)
 	geo->gf_len = 13;
 
 	/* The default for chunk size. */
-	geo->ecc_chunk_size = 512;
-	while (geo->ecc_chunk_size < mtd->oobsize) {
-		geo->ecc_chunk_size *= 2; /* keep C >= O */
+	geo->ecc_chunk0_size = 512;
+	geo->ecc_chunkn_size = 512;
+	while (geo->ecc_chunkn_size < mtd->oobsize) {
+		geo->ecc_chunk0_size *= 2; /* keep C >= O */
+		geo->ecc_chunkn_size *= 2; /* keep C >= O */
 		geo->gf_len = 14;
 	}
 
-	geo->ecc_chunk_count = mtd->writesize / geo->ecc_chunk_size;
+	geo->ecc_chunk_count = mtd->writesize / geo->ecc_chunkn_size;
 
 	/* We use the same ECC strength for all chunks. */
 	geo->ecc_strength = get_ecc_strength(this);

@@ -514,24 +677,23 @@ static int legacy_set_geometry(struct gpmi_nand_data *this)
 static int common_nfc_set_geometry(struct gpmi_nand_data *this)
 {
 	struct nand_chip *chip = &this->nand;
+	struct mtd_info *mtd = nand_to_mtd(&this->nand);
 	const struct nand_ecc_props *requirements =
 		nanddev_get_ecc_requirements(&chip->base);
 
-	if (chip->ecc.strength > 0 && chip->ecc.size > 0)
-		return set_geometry_by_ecc_info(this, chip->ecc.strength,
-						chip->ecc.size);
-
-	if ((of_property_read_bool(this->dev->of_node, "fsl,use-minimum-ecc"))
-				|| legacy_set_geometry(this)) {
-		if (!(requirements->strength > 0 && requirements->step_size > 0))
-			return -EINVAL;
+	/* first check if need to use legacy bch geometry settings */
+	if ((!(requirements->strength > 0 && requirements->step_size > 0) &&
+	    mtd->oobsize < 1024) ||
+	    of_property_read_bool(this->dev->of_node, "fsl,legacy-bch-geometry"))
+		return legacy_set_geometry(this);
 
-		return set_geometry_by_ecc_info(this,
-						requirements->strength,
-						requirements->step_size);
-	}
+	/* then check if need to set bch geometry for large oob nand */
+	if (mtd->oobsize > 1024 || requirements->step_size < mtd->oobsize)
+		return set_geometry_for_large_oob(this);
 
-	return 0;
+	/* set bch geometry by nand chip minimum required strength & step size*/
+	return set_geometry_by_ecc_info(this, requirements->strength,
+					requirements->step_size);
 }
 
 /* Configures the geometry for BCH.  */

@@ -806,7 +968,7 @@ static int gpmi_raw_len_to_len(struct gpmi_nand_data *this, int raw_len)
 	 * we are passed in exec_op. Calculate the data length from it.
 	 */
 	if (this->bch)
-		return ALIGN_DOWN(raw_len, this->bch_geometry.ecc_chunk_size);
+		return ALIGN_DOWN(raw_len, this->bch_geometry.ecc_chunkn_size);
 	else
 		return raw_len;
 }

@@ -1212,7 +1374,7 @@ static int gpmi_count_bitflips(struct nand_chip *chip, void *buf, int first,
 
 			/* Read ECC bytes into our internal raw_buffer */
 			offset = nfc_geo->metadata_size * 8;
-			offset += ((8 * nfc_geo->ecc_chunk_size) + eccbits) * (i + 1);
+			offset += ((8 * nfc_geo->ecc_chunkn_size) + eccbits) * (i + 1);
 			offset -= eccbits;
 			bitoffset = offset % 8;
 			eccbytes = DIV_ROUND_UP(offset + eccbits, 8);

@@ -1249,16 +1411,16 @@ static int gpmi_count_bitflips(struct nand_chip *chip, void *buf, int first,
 			if (i == 0) {
 				/* The first block includes metadata */
 				flips = nand_check_erased_ecc_chunk(
-						buf + i * nfc_geo->ecc_chunk_size,
-						nfc_geo->ecc_chunk_size,
+						buf + i * nfc_geo->ecc_chunkn_size,
+						nfc_geo->ecc_chunkn_size,
 						eccbuf, eccbytes,
 						this->auxiliary_virt,
 						nfc_geo->metadata_size,
 						nfc_geo->ecc_strength);
 			} else {
 				flips = nand_check_erased_ecc_chunk(
-						buf + i * nfc_geo->ecc_chunk_size,
-						nfc_geo->ecc_chunk_size,
+						buf + i * nfc_geo->ecc_chunkn_size,
+						nfc_geo->ecc_chunkn_size,
 						eccbuf, eccbytes,
 						NULL, 0,
 						nfc_geo->ecc_strength);

@@ -1287,20 +1449,21 @@ static void gpmi_bch_layout_std(struct gpmi_nand_data *this)
 	struct bch_geometry *geo = &this->bch_geometry;
 	unsigned int ecc_strength = geo->ecc_strength >> 1;
 	unsigned int gf_len = geo->gf_len;
-	unsigned int block_size = geo->ecc_chunk_size;
+	unsigned int block0_size = geo->ecc_chunk0_size;
+	unsigned int blockn_size = geo->ecc_chunkn_size;
 
 	this->bch_flashlayout0 =
 		BF_BCH_FLASH0LAYOUT0_NBLOCKS(geo->ecc_chunk_count - 1) |
 		BF_BCH_FLASH0LAYOUT0_META_SIZE(geo->metadata_size) |
 		BF_BCH_FLASH0LAYOUT0_ECC0(ecc_strength, this) |
 		BF_BCH_FLASH0LAYOUT0_GF(gf_len, this) |
-		BF_BCH_FLASH0LAYOUT0_DATA0_SIZE(block_size, this);
+		BF_BCH_FLASH0LAYOUT0_DATA0_SIZE(block0_size, this);
 
 	this->bch_flashlayout1 =
 		BF_BCH_FLASH0LAYOUT1_PAGE_SIZE(geo->page_size) |
 		BF_BCH_FLASH0LAYOUT1_ECCN(ecc_strength, this) |
 		BF_BCH_FLASH0LAYOUT1_GF(gf_len, this) |
-		BF_BCH_FLASH0LAYOUT1_DATAN_SIZE(block_size, this);
+		BF_BCH_FLASH0LAYOUT1_DATAN_SIZE(blockn_size, this);
 }
 
 static int gpmi_ecc_read_page(struct nand_chip *chip, uint8_t *buf,

@@ -1383,9 +1546,22 @@ static int gpmi_ecc_read_subpage(struct nand_chip *chip, uint32_t offs,
 		}
 	}
 
+	/*
+	 * if there is an ECC dedicate for meta:
+	 * - need to add an extra ECC size when calculating col and page_size,
+	 *   if the meta size is NOT zero.
+	 * - chunk0 size need to set to the same size as other chunks,
+	 *   if the meta size is zero.
+	 */
+
 	meta = geo->metadata_size;
 	if (first) {
-		col = meta + (size + ecc_parity_size) * first;
+		if (geo->ecc_for_meta)
+			col = meta + ecc_parity_size
+				+ (size + ecc_parity_size) * first;
+		else
+			col = meta + (size + ecc_parity_size) * first;
+
 		meta = 0;
 		buf = buf + first * size;
 	}

@@ -1393,19 +1569,27 @@ static int gpmi_ecc_read_subpage(struct nand_chip *chip, uint32_t offs,
 	ecc_parity_size = geo->gf_len * geo->ecc_strength / 8;
 
 	n = last - first + 1;
-	page_size = meta + (size + ecc_parity_size) * n;
+
+	if (geo->ecc_for_meta && meta)
+		page_size = meta + ecc_parity_size
+			+ (size + ecc_parity_size) * n;
+	else
+		page_size = meta + (size + ecc_parity_size) * n;
+
 	ecc_strength = geo->ecc_strength >> 1;
 
-	this->bch_flashlayout0 = BF_BCH_FLASH0LAYOUT0_NBLOCKS(n - 1) |
+	this->bch_flashlayout0 = BF_BCH_FLASH0LAYOUT0_NBLOCKS(
+		(geo->ecc_for_meta ? n : n - 1)) |
 		BF_BCH_FLASH0LAYOUT0_META_SIZE(meta) |
 		BF_BCH_FLASH0LAYOUT0_ECC0(ecc_strength, this) |
 		BF_BCH_FLASH0LAYOUT0_GF(geo->gf_len, this) |
-		BF_BCH_FLASH0LAYOUT0_DATA0_SIZE(geo->ecc_chunk_size, this);
+		BF_BCH_FLASH0LAYOUT0_DATA0_SIZE((geo->ecc_for_meta ?
+		0 : geo->ecc_chunk0_size), this);
 
 	this->bch_flashlayout1 = BF_BCH_FLASH0LAYOUT1_PAGE_SIZE(page_size) |
 		BF_BCH_FLASH0LAYOUT1_ECCN(ecc_strength, this) |
 		BF_BCH_FLASH0LAYOUT1_GF(geo->gf_len, this) |
-		BF_BCH_FLASH0LAYOUT1_DATAN_SIZE(geo->ecc_chunk_size, this);
+		BF_BCH_FLASH0LAYOUT1_DATAN_SIZE(geo->ecc_chunkn_size, this);
 
 	this->bch = true;
 

@@ -1577,7 +1761,7 @@ static int gpmi_ecc_read_page_raw(struct nand_chip *chip, uint8_t *buf,
 	struct mtd_info *mtd = nand_to_mtd(chip);
 	struct gpmi_nand_data *this = nand_get_controller_data(chip);
 	struct bch_geometry *nfc_geo = &this->bch_geometry;
-	int eccsize = nfc_geo->ecc_chunk_size;
+	int eccsize = nfc_geo->ecc_chunkn_size;
 	int eccbits = nfc_geo->ecc_strength * nfc_geo->gf_len;
 	u8 *tmp_buf = this->raw_buffer;
 	size_t src_bit_off;

@@ -1662,7 +1846,7 @@ static int gpmi_ecc_write_page_raw(struct nand_chip *chip, const uint8_t *buf,
 	struct mtd_info *mtd = nand_to_mtd(chip);
 	struct gpmi_nand_data *this = nand_get_controller_data(chip);
 	struct bch_geometry *nfc_geo = &this->bch_geometry;
-	int eccsize = nfc_geo->ecc_chunk_size;
+	int eccsize = nfc_geo->ecc_chunkn_size;
 	int eccbits = nfc_geo->ecc_strength * nfc_geo->gf_len;
 	u8 *tmp_buf = this->raw_buffer;
 	uint8_t *oob = chip->oob_poi;

@@ -2036,7 +2220,7 @@ static int gpmi_init_last(struct gpmi_nand_data *this)
 	ecc->read_oob_raw = gpmi_ecc_read_oob_raw;
 	ecc->write_oob_raw = gpmi_ecc_write_oob_raw;
 	ecc->engine_type = NAND_ECC_ENGINE_TYPE_ON_HOST;
-	ecc->size	= bch_geo->ecc_chunk_size;
+	ecc->size	= bch_geo->ecc_chunkn_size;
 	ecc->strength	= bch_geo->ecc_strength;
 	mtd_set_ooblayout(mtd, &gpmi_ooblayout_ops);
 

index fdc5ed7de083..e612f5c22293 100644
@@ -30,9 +30,9 @@ struct resources {
  * @page_size:                The size, in bytes, of a physical page, including
  *                            both data and OOB.
  * @metadata_size:            The size, in bytes, of the metadata.
- * @ecc_chunk_size:           The size, in bytes, of a single ECC chunk. Note
- *                            the first chunk in the page includes both data and
- *                            metadata, so it's a bit larger than this value.
+ * @ecc_chunk0_size:          The size, in bytes, of a first ECC chunk.
+ * @ecc_chunkn_size:          The size, in bytes, of a single ECC chunk after
+ *                            the first chunk in the page.
  * @ecc_chunk_count:          The number of ECC chunks in the page,
  * @payload_size:             The size, in bytes, of the payload buffer.
  * @auxiliary_size:           The size, in bytes, of the auxiliary buffer.

@@ -42,19 +42,23 @@ struct resources {
  *                            which the underlying physical block mark appears.
  * @block_mark_bit_offset:    The bit offset into the ECC-based page view at
  *                            which the underlying physical block mark appears.
+ * @ecc_for_meta:             The flag to indicate if there is a dedicate ecc
+ *                            for meta.
  */
 struct bch_geometry {
 	unsigned int  gf_len;
 	unsigned int  ecc_strength;
 	unsigned int  page_size;
 	unsigned int  metadata_size;
-	unsigned int  ecc_chunk_size;
+	unsigned int  ecc_chunk0_size;
+	unsigned int  ecc_chunkn_size;
 	unsigned int  ecc_chunk_count;
 	unsigned int  payload_size;
 	unsigned int  auxiliary_size;
 	unsigned int  auxiliary_status_offset;
 	unsigned int  block_mark_byte_offset;
 	unsigned int  block_mark_bit_offset;
+	unsigned int  ecc_for_meta; /* ECC for meta data */
 };
 
 /**

2.17.1
---
 Documentation/devicetree/bindings/mtd/gpmi-nand.yaml | 9 +++++++++
 1 file changed, 9 insertions(+)
index 9d764e654e1d..5f4eddd132a1 100644
@@ -62,6 +62,7 @@ properties:
 
   fsl,use-minimum-ecc:
     type: boolean
+    deprecated: true
     description: |
       Protect this NAND flash with the minimum ECC strength required.
       The required ECC strength is automatically discoverable for some

@@ -69,6 +70,14 @@ properties:
       if this strength is not discoverable or this property is not enabled,
       the software may chooses an implementation-defined ECC scheme.
 
+  fsl,legacy-bch-geometry:
+    type: boolean
+    description: |
+      Enable the legacy bch geometry setting, which will set the data chunk
+      size larger than oob size and chose the maximum ecc strength oob can
+      hold. This flag was designed for backward compatible or old NAND chip
+      support, should be en/disabled in u-boot and kernel at the same time.
+
   fsl,no-blockmark-swap:
     type: boolean
     description: |

2.17.1

mtd: nand: raw: gpmi: new bch geometry settings

Han Xu

Han Xu

Sean Nyekjaer

Han Xu

Miquel Raynal

Han Xu

Miquel Raynal

Sean Nyekjaer

Han Xu

Sean Nyekjaer

Miquel Raynal