[PATCH v4 42/52] mtd: nand: omap2: switch to mtd_ooblayout_ops

From: Boris Brezillon
Date: Mon Mar 07 2016 - 04:55:57 EST

Implementing the mtd_ooblayout_ops interface is the new way of exposing
ECC/OOB layout to MTD users.

Signed-off-by: Boris Brezillon <boris.brezillon@xxxxxxxxxxxxxxxxxx>
---
drivers/mtd/nand/omap2.c | 194 +++++++++++++++++++++++++++--------------------
1 file changed, 113 insertions(+), 81 deletions(-)

diff --git a/drivers/mtd/nand/omap2.c b/drivers/mtd/nand/omap2.c
index 4ebf16b..bca154a 100644
--- a/drivers/mtd/nand/omap2.c
+++ b/drivers/mtd/nand/omap2.c
@@ -169,8 +169,6 @@ struct omap_nand_info {
u_char *buf;
int buf_len;
struct gpmc_nand_regs reg;
- /* generated at runtime depending on ECC algorithm and layout selected */
- struct nand_ecclayout oobinfo;
/* fields specific for BCHx_HW ECC scheme */
struct device *elm_dev;
struct device_node *of_node;
@@ -1639,19 +1637,108 @@ static bool omap2_nand_ecc_check(struct omap_nand_info *info,
return true;
}

+static int omap_ooblayout_ecc(struct mtd_info *mtd, int section,
+ struct mtd_oob_region *oobregion)
+{
+ struct nand_chip *chip = mtd_to_nand(mtd);
+ int off = chip->options & NAND_BUSWIDTH_16 ?
+ BADBLOCK_MARKER_LENGTH : 1;
+
+ if (section)
+ return -ERANGE;
+
+ oobregion->offset = off;
+ oobregion->length = chip->ecc.total;
+
+ return 0;
+}
+
+static int omap_ooblayout_free(struct mtd_info *mtd, int section,
+ struct mtd_oob_region *oobregion)
+{
+ struct nand_chip *chip = mtd_to_nand(mtd);
+ int off = chip->options & NAND_BUSWIDTH_16 ?
+ BADBLOCK_MARKER_LENGTH : 1;
+
+ if (section)
+ return -ERANGE;
+
+ off += chip->ecc.total;
+ if (off >= mtd->oobsize)
+ return -ERANGE;
+
+ oobregion->offset = off;
+ oobregion->length = mtd->oobsize - off;
+
+ return 0;
+}
+
+static const struct mtd_ooblayout_ops omap_ooblayout_ops = {
+ .ecc = omap_ooblayout_ecc,
+ .free = omap_ooblayout_free,
+};
+
+static int omap_sw_ooblayout_ecc(struct mtd_info *mtd, int section,
+ struct mtd_oob_region *oobregion)
+{
+ struct nand_chip *chip = mtd_to_nand(mtd);
+ int off = chip->options & NAND_BUSWIDTH_16 ?
+ BADBLOCK_MARKER_LENGTH : 1;
+
+ if (section >= chip->ecc.steps)
+ return -ERANGE;
+
+ /*
+ * When SW correction is employed, one OMAP specific marker byte is
+ * reserved after each ECC step.
+ */
+ oobregion->offset = off + (section * (chip->ecc.bytes + 1));
+ oobregion->length = chip->ecc.bytes;
+
+ return 0;
+}
+
+static int omap_sw_ooblayout_free(struct mtd_info *mtd, int section,
+ struct mtd_oob_region *oobregion)
+{
+ struct nand_chip *chip = mtd_to_nand(mtd);
+ int off = chip->options & NAND_BUSWIDTH_16 ?
+ BADBLOCK_MARKER_LENGTH : 1;
+
+ if (section)
+ return -ERANGE;
+
+ /*
+ * When SW correction is employed, one OMAP specific marker byte is
+ * reserved after each ECC step.
+ */
+ off += ((chip->ecc.bytes + 1) * chip->ecc.steps);
+ if (off >= mtd->oobsize)
+ return -ERANGE;
+
+ oobregion->offset = off;
+ oobregion->length = mtd->oobsize - off;
+
+ return 0;
+}
+
+static const struct mtd_ooblayout_ops omap_sw_ooblayout_ops = {
+ .ecc = omap_sw_ooblayout_ecc,
+ .free = omap_sw_ooblayout_free,
+};
+
static int omap_nand_probe(struct platform_device *pdev)
{
struct omap_nand_info *info;
struct omap_nand_platform_data *pdata;
struct mtd_info *mtd;
struct nand_chip *nand_chip;
- struct nand_ecclayout *ecclayout;
int err;
- int i;
dma_cap_mask_t mask;
unsigned sig;
- unsigned oob_index;
struct resource *res;
+ int min_oobbytes;
+ int oobbytes_per_step;

pdata = dev_get_platdata(&pdev->dev);
if (pdata == NULL) {
@@ -1810,7 +1897,7 @@ static int omap_nand_probe(struct platform_device *pdev)

/*
* Bail out earlier to let NAND_ECC_SOFT code create its own
- * ecclayout instead of using ours.
+ * ooblayout instead of using ours.
*/
if (info->ecc_opt == OMAP_ECC_HAM1_CODE_SW) {
nand_chip->ecc.mode = NAND_ECC_SOFT;
@@ -1818,8 +1905,6 @@ static int omap_nand_probe(struct platform_device *pdev)
}

/* populate MTD interface based on ECC scheme */
- ecclayout = &info->oobinfo;
- nand_chip->ecc.layout = ecclayout;
switch (info->ecc_opt) {
case OMAP_ECC_HAM1_CODE_HW:
pr_info("nand: using OMAP_ECC_HAM1_CODE_HW\n");
@@ -1830,19 +1915,8 @@ static int omap_nand_probe(struct platform_device *pdev)
nand_chip->ecc.calculate = omap_calculate_ecc;
nand_chip->ecc.hwctl = omap_enable_hwecc;
nand_chip->ecc.correct = omap_correct_data;
- /* define ECC layout */
- ecclayout->eccbytes = nand_chip->ecc.bytes *
- (mtd->writesize /
- nand_chip->ecc.size);
- if (nand_chip->options & NAND_BUSWIDTH_16)
- oob_index = BADBLOCK_MARKER_LENGTH;
- else
- oob_index = 1;
- for (i = 0; i < ecclayout->eccbytes; i++, oob_index++)
- ecclayout->eccpos[i] = oob_index;
- /* no reserved-marker in ecclayout for this ecc-scheme */
- ecclayout->oobfree->offset =
- ecclayout->eccpos[ecclayout->eccbytes - 1] + 1;
+ mtd_set_ooblayout(mtd, &omap_ooblayout_ops);
+ oobbytes_per_step = nand_chip->ecc.bytes;
break;

case OMAP_ECC_BCH4_CODE_HW_DETECTION_SW:
@@ -1854,19 +1928,9 @@ static int omap_nand_probe(struct platform_device *pdev)
nand_chip->ecc.hwctl = omap_enable_hwecc_bch;
nand_chip->ecc.correct = nand_bch_correct_data;
nand_chip->ecc.calculate = omap_calculate_ecc_bch;
- /* define ECC layout */
- ecclayout->eccbytes = nand_chip->ecc.bytes *
- (mtd->writesize /
- nand_chip->ecc.size);
- oob_index = BADBLOCK_MARKER_LENGTH;
- for (i = 0; i < ecclayout->eccbytes; i++, oob_index++) {
- ecclayout->eccpos[i] = oob_index;
- if (((i + 1) % nand_chip->ecc.bytes) == 0)
- oob_index++;
- }
- /* include reserved-marker in ecclayout->oobfree calculation */
- ecclayout->oobfree->offset = 1 +
- ecclayout->eccpos[ecclayout->eccbytes - 1] + 1;
+ mtd_set_ooblayout(mtd, &omap_sw_ooblayout_ops);
+ /* Reserve one byte for the OMAP marker */
+ oobbytes_per_step = nand_chip->ecc.bytes + 1;
/* software bch library is used for locating errors */
nand_chip->ecc.priv = nand_bch_init(mtd);
if (!nand_chip->ecc.priv) {
@@ -1888,16 +1952,8 @@ static int omap_nand_probe(struct platform_device *pdev)
nand_chip->ecc.calculate = omap_calculate_ecc_bch;
nand_chip->ecc.read_page = omap_read_page_bch;
nand_chip->ecc.write_page = omap_write_page_bch;
- /* define ECC layout */
- ecclayout->eccbytes = nand_chip->ecc.bytes *
- (mtd->writesize /
- nand_chip->ecc.size);
- oob_index = BADBLOCK_MARKER_LENGTH;
- for (i = 0; i < ecclayout->eccbytes; i++, oob_index++)
- ecclayout->eccpos[i] = oob_index;
- /* reserved marker already included in ecclayout->eccbytes */
- ecclayout->oobfree->offset =
- ecclayout->eccpos[ecclayout->eccbytes - 1] + 1;
+ mtd_set_ooblayout(mtd, &omap_ooblayout_ops);
+ oobbytes_per_step = nand_chip->ecc.bytes;

err = elm_config(info->elm_dev, BCH4_ECC,
mtd->writesize / nand_chip->ecc.size,
@@ -1915,19 +1971,9 @@ static int omap_nand_probe(struct platform_device *pdev)
nand_chip->ecc.hwctl = omap_enable_hwecc_bch;
nand_chip->ecc.correct = nand_bch_correct_data;
nand_chip->ecc.calculate = omap_calculate_ecc_bch;
- /* define ECC layout */
- ecclayout->eccbytes = nand_chip->ecc.bytes *
- (mtd->writesize /
- nand_chip->ecc.size);
- oob_index = BADBLOCK_MARKER_LENGTH;
- for (i = 0; i < ecclayout->eccbytes; i++, oob_index++) {
- ecclayout->eccpos[i] = oob_index;
- if (((i + 1) % nand_chip->ecc.bytes) == 0)
- oob_index++;
- }
- /* include reserved-marker in ecclayout->oobfree calculation */
- ecclayout->oobfree->offset = 1 +
- ecclayout->eccpos[ecclayout->eccbytes - 1] + 1;
+ mtd_set_ooblayout(mtd, &omap_sw_ooblayout_ops);
+ /* Reserve one byte for the OMAP marker */
+ oobbytes_per_step = nand_chip->ecc.bytes + 1;
/* software bch library is used for locating errors */
nand_chip->ecc.priv = nand_bch_init(mtd);
if (!nand_chip->ecc.priv) {
@@ -1949,6 +1995,8 @@ static int omap_nand_probe(struct platform_device *pdev)
nand_chip->ecc.calculate = omap_calculate_ecc_bch;
nand_chip->ecc.read_page = omap_read_page_bch;
nand_chip->ecc.write_page = omap_write_page_bch;
+ mtd_set_ooblayout(mtd, &omap_ooblayout_ops);
+ oobbytes_per_step = nand_chip->ecc.bytes;

err = elm_config(info->elm_dev, BCH8_ECC,
mtd->writesize / nand_chip->ecc.size,
@@ -1956,16 +2004,6 @@ static int omap_nand_probe(struct platform_device *pdev)
if (err < 0)
goto return_error;

- /* define ECC layout */
- ecclayout->eccbytes = nand_chip->ecc.bytes *
- (mtd->writesize /
- nand_chip->ecc.size);
- oob_index = BADBLOCK_MARKER_LENGTH;
- for (i = 0; i < ecclayout->eccbytes; i++, oob_index++)
- ecclayout->eccpos[i] = oob_index;
- /* reserved marker already included in ecclayout->eccbytes */
- ecclayout->oobfree->offset =
- ecclayout->eccpos[ecclayout->eccbytes - 1] + 1;
break;

case OMAP_ECC_BCH16_CODE_HW:
@@ -1979,6 +2017,8 @@ static int omap_nand_probe(struct platform_device *pdev)
nand_chip->ecc.calculate = omap_calculate_ecc_bch;
nand_chip->ecc.read_page = omap_read_page_bch;
nand_chip->ecc.write_page = omap_write_page_bch;
+ mtd_set_ooblayout(mtd, &omap_ooblayout_ops);
+ oobbytes_per_step = nand_chip->ecc.bytes;

err = elm_config(info->elm_dev, BCH16_ECC,
mtd->writesize / nand_chip->ecc.size,
@@ -1986,16 +2026,6 @@ static int omap_nand_probe(struct platform_device *pdev)
if (err < 0)
goto return_error;

- /* define ECC layout */
- ecclayout->eccbytes = nand_chip->ecc.bytes *
- (mtd->writesize /
- nand_chip->ecc.size);
- oob_index = BADBLOCK_MARKER_LENGTH;
- for (i = 0; i < ecclayout->eccbytes; i++, oob_index++)
- ecclayout->eccpos[i] = oob_index;
- /* reserved marker already included in ecclayout->eccbytes */
- ecclayout->oobfree->offset =
- ecclayout->eccpos[ecclayout->eccbytes - 1] + 1;
break;
default:
dev_err(&info->pdev->dev, "invalid or unsupported ECC scheme\n");
@@ -2003,13 +2033,15 @@ static int omap_nand_probe(struct platform_device *pdev)
goto return_error;
}

- /* all OOB bytes from oobfree->offset till end off OOB are free */
- ecclayout->oobfree->length = mtd->oobsize - ecclayout->oobfree->offset;
/* check if NAND device's OOB is enough to store ECC signatures */
- if (mtd->oobsize < (ecclayout->eccbytes + BADBLOCK_MARKER_LENGTH)) {
+ min_oobbytes = (oobbytes_per_step *
+ (mtd->writesize / nand_chip->ecc.size)) +
+ (nand_chip->options & NAND_BUSWIDTH_16 ?
+ BADBLOCK_MARKER_LENGTH : 1);
+ if (mtd->oobsize < min_oobbytes) {
dev_err(&info->pdev->dev,
"not enough OOB bytes required = %d, available=%d\n",
- ecclayout->eccbytes, mtd->oobsize);
+ min_oobbytes, mtd->oobsize);
err = -EINVAL;
goto return_error;
}
--
2.1.4