[PATCH 4/4] mtd: spinand: micron: Support for new Micron SPI NAND flashes

[Shivamurthy Shastri (sshivamurthy)]

Driver is redesigned using parameter page to support Micron SPI NAND
flashes.

Support for selecting die is enabled for multi-die flashes.
Turn OOB layout generic.

Fixup some of the parameter page data as per Micron datasheet.

Signed-off-by: Shivamurthy Shastri <sshivamurthy@xxxxxxxxxx>
---
 drivers/mtd/nand/spi/micron.c | 109 +++++++++++++++++++++++++---------
 1 file changed, 80 insertions(+), 29 deletions(-)

diff --git a/drivers/mtd/nand/spi/micron.c b/drivers/mtd/nand/spi/micron.c
index 7d7b1f7fcf71..663bb2809036 100644
--- a/drivers/mtd/nand/spi/micron.c
+++ b/drivers/mtd/nand/spi/micron.c
@@ -14,7 +14,7 @@
 
 #define MICRON_STATUS_ECC_MASK		GENMASK(7, 4)
 #define MICRON_STATUS_ECC_NO_BITFLIPS	(0 << 4)
-#define MICRON_STATUS_ECC_1TO3_BITFLIPS	(1 << 4)
+#define MICRON_STATUS_ECC_1TO3_BITFLIPS	BIT(4)
 #define MICRON_STATUS_ECC_4TO6_BITFLIPS	(3 << 4)
 #define MICRON_STATUS_ECC_7TO8_BITFLIPS	(5 << 4)
 
@@ -34,38 +34,38 @@ static SPINAND_OP_VARIANTS(update_cache_variants,
 		SPINAND_PROG_LOAD_X4(false, 0, NULL, 0),
 		SPINAND_PROG_LOAD(false, 0, NULL, 0));
 
-static int mt29f2g01abagd_ooblayout_ecc(struct mtd_info *mtd, int section,
-					struct mtd_oob_region *region)
+static int ooblayout_ecc(struct mtd_info *mtd, int section,
+			 struct mtd_oob_region *region)
 {
 	if (section)
 		return -ERANGE;
 
-	region->offset = 64;
-	region->length = 64;
+	region->offset = mtd->oobsize / 2;
+	region->length = mtd->oobsize / 2;
 
 	return 0;
 }
 
-static int mt29f2g01abagd_ooblayout_free(struct mtd_info *mtd, int section,
-					 struct mtd_oob_region *region)
+static int ooblayout_free(struct mtd_info *mtd, int section,
+			  struct mtd_oob_region *region)
 {
 	if (section)
 		return -ERANGE;
 
 	/* Reserve 2 bytes for the BBM. */
 	region->offset = 2;
-	region->length = 62;
+	region->length = (mtd->oobsize / 2) - 2;
 
 	return 0;
 }
 
-static const struct mtd_ooblayout_ops mt29f2g01abagd_ooblayout = {
-	.ecc = mt29f2g01abagd_ooblayout_ecc,
-	.free = mt29f2g01abagd_ooblayout_free,
+static const struct mtd_ooblayout_ops ooblayout = {
+	.ecc = ooblayout_ecc,
+	.free = ooblayout_free,
 };
 
-static int mt29f2g01abagd_ecc_get_status(struct spinand_device *spinand,
-					 u8 status)
+static int ecc_get_status(struct spinand_device *spinand,
+			  u8 status)
 {
 	switch (status & MICRON_STATUS_ECC_MASK) {
 	case STATUS_ECC_NO_BITFLIPS:
@@ -90,22 +90,23 @@ static int mt29f2g01abagd_ecc_get_status(struct spinand_device *spinand,
 	return -EINVAL;
 }
 
-static const struct spinand_info micron_spinand_table[] = {
-	SPINAND_INFO("MT29F2G01ABAGD", 0x24,
-		     NAND_MEMORG(1, 2048, 128, 64, 2048, 40, 2, 1, 1),
-		     NAND_ECCREQ(8, 512),
-		     SPINAND_INFO_OP_VARIANTS(&read_cache_variants,
-					      &write_cache_variants,
-					      &update_cache_variants),
-		     0,
-		     SPINAND_ECCINFO(&mt29f2g01abagd_ooblayout,
-				     mt29f2g01abagd_ecc_get_status)),
-};
+static int mt29f8g_select_target(struct spinand_device *spinand,
+				 unsigned int target)
+{
+	struct spi_mem_op op = SPINAND_SET_FEATURE_OP(0xd0,
+							spinand->scratchbuf);
+
+	if (target == 1)
+		target = 0x40;
+
+	*spinand->scratchbuf = target;
+	return spi_mem_exec_op(spinand->spimem, &op);
+}
 
 static int micron_spinand_detect(struct spinand_device *spinand)
 {
+	const struct spi_mem_op *op;
 	u8 *id = spinand->id.data;
-	int ret;
 
 	/*
 	 * Micron SPI NAND read ID need a dummy byte,
@@ -114,16 +115,66 @@ static int micron_spinand_detect(struct spinand_device *spinand)
 	if (id[1] != SPINAND_MFR_MICRON)
 		return 0;
 
-	ret = spinand_match_and_init(spinand, micron_spinand_table,
-				     ARRAY_SIZE(micron_spinand_table), id[2]);
-	if (ret)
-		return ret;
+	spinand->flags = 0;
+	spinand->eccinfo.get_status = ecc_get_status;
+	spinand->eccinfo.ooblayout = &ooblayout;
+	spinand->select_target = mt29f8g_select_target;
+
+	op = spinand_select_op_variant(spinand,
+				       &read_cache_variants);
+	if (!op)
+		return -ENOTSUPP;
+
+	spinand->op_templates.read_cache = op;
+
+	op = spinand_select_op_variant(spinand,
+				       &write_cache_variants);
+	if (!op)
+		return -ENOTSUPP;
+
+	spinand->op_templates.write_cache = op;
+
+	op = spinand_select_op_variant(spinand,
+				       &update_cache_variants);
+	spinand->op_templates.update_cache = op;
 
 	return 1;
 }
 
+static int micron_spinand_init(struct spinand_device *spinand)
+{
+	/*
+	 * Some of the Micron flashes enable this BIT by default,
+	 * and there is a chance of read failure due to this.
+	 */
+	return spinand_upd_cfg(spinand, CFG_QUAD_ENABLE, 0);
+}
+
+static void micron_fixup_param_page(struct spinand_device *spinand,
+				    struct nand_onfi_params *p)
+{
+	/**
+	 * As per Micron datasheets vendor[88] is defined as
+	 * die_select_feature
+	 */
+	if (p->vendor[83] && !p->interleaved_bits)
+		spinand->base.memorg.planes_per_lun = 1 << p->vendor[0];
+
+	spinand->base.memorg.ntargets = p->lun_count;
+	spinand->base.memorg.luns_per_target = 1;
+
+	/**
+	 * As per Micron datasheets,
+	 * vendor[82] is ECC maximum correctability
+	 */
+	spinand->base.ecc.requirements.strength = p->vendor[82];
+	spinand->base.ecc.requirements.step_size = 512;
+}
+
 static const struct spinand_manufacturer_ops micron_spinand_manuf_ops = {
 	.detect = micron_spinand_detect,
+	.init = micron_spinand_init,
+	.fixup_param_page = micron_fixup_param_page,
 };
 
 const struct spinand_manufacturer micron_spinand_manufacturer = {
-- 
2.17.1