[PATCH v2 27/51] mtd: nand: brcm: switch to mtd_ooblayout_ops

Boris Brezillon
2016-02-04T10:19:34Z

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@free-electrons.com>
---
drivers/mtd/nand/brcmnand/brcmnand.c | 258 +++++++++++++++++++++--------------
1 file changed, 157 insertions(+), 101 deletions(-)

diff --git a/drivers/mtd/nand/brcmnand/brcmnand.c b/drivers/mtd/nand/brcmnand/brcmnand.c
index b86882b..169a095 100644
--- a/drivers/mtd/nand/brcmnand/brcmnand.c
+++ b/drivers/mtd/nand/brcmnand/brcmnand.c
@@ -749,127 +749,183 @@ static inline bool is_hamming_ecc(struct brcmnand_cfg *cfg)
}

/*
- * Returns a nand_ecclayout strucutre for the given layout/configuration.
- * Returns NULL on failure.
+ * Set mtd->ooblayout to the appropriate mtd_ooblayout_ops given
+ * the layout/configuration.
+ * Returns -ERRCODE on failure.
*/
-static struct nand_ecclayout *brcmnand_create_layout(int ecc_level,
- struct brcmnand_host *host)
+static int brcmnand_hamming_ooblayout_ecc(struct mtd_info *mtd, int section,
+ struct mtd_oob_region *oobregion)
{
+ struct nand_chip *chip = mtd_to_nand(mtd);
+ struct brcmnand_host *host = nand_get_controller_data(chip);
struct brcmnand_cfg *cfg = &host->hwcfg;
- int i, j;
- struct nand_ecclayout *layout;
- int req;
- int sectors;
- int sas;
- int idx1, idx2;
-
- layout = devm_kzalloc(&host->pdev->dev, sizeof(*layout), GFP_KERNEL);
- if (!layout)
- return NULL;
-
- sectors = cfg->page_size / (512 << cfg->sector_size_1k);
- sas = cfg->spare_area_size << cfg->sector_size_1k;
-
- /* Hamming */
- if (is_hamming_ecc(cfg)) {
- for (i = 0, idx1 = 0, idx2 = 0; i < sectors; i++) {
- /* First sector of each page may have BBI */
- if (i == 0) {
- layout->oobfree[idx2].offset = i * sas + 1;
- /* Small-page NAND use byte 6 for BBI */
- if (cfg->page_size == 512)
- layout->oobfree[idx2].offset--;
- layout->oobfree[idx2].length = 5;
- } else {
- layout->oobfree[idx2].offset = i * sas;
- layout->oobfree[idx2].length = 6;
- }
- idx2++;
- layout->eccpos[idx1++] = i * sas + 6;
- layout->eccpos[idx1++] = i * sas + 7;
- layout->eccpos[idx1++] = i * sas + 8;
- layout->oobfree[idx2].offset = i * sas + 9;
- layout->oobfree[idx2].length = 7;
- idx2++;
- /* Leave zero-terminated entry for OOBFREE */
- if (idx1 >= MTD_MAX_ECCPOS_ENTRIES_LARGE ||
- idx2 >= MTD_MAX_OOBFREE_ENTRIES_LARGE - 1)
- break;
- }
+ int sas = cfg->spare_area_size << cfg->sector_size_1k;
+ int sectors = cfg->page_size / (512 << cfg->sector_size_1k);

- return layout;
- }
+ if (section >= sectors)
+ return -ERANGE;

- /*
- * CONTROLLER_VERSION:
- * < v5.0: ECC_REQ = ceil(BCH_T * 13/8)
- * >= v5.0: ECC_REQ = ceil(BCH_T * 14/8)
- * But we will just be conservative.
- */
- req = DIV_ROUND_UP(ecc_level * 14, 8);
- if (req >= sas) {
- dev_err(&host->pdev->dev,
- "error: ECC too large for OOB (ECC bytes %d, spare sector %d)\n",
- req, sas);
- return NULL;
- }
+ oobregion->offset = (section * sas) + 6;
+ oobregion->length = 3;
+
+ return 0;
+}
+
+static int brcmnand_hamming_ooblayout_free(struct mtd_info *mtd, int section,
+ struct mtd_oob_region *oobregion)
+{
+ struct nand_chip *chip = mtd_to_nand(mtd);
+ struct brcmnand_host *host = nand_get_controller_data(chip);
+ struct brcmnand_cfg *cfg = &host->hwcfg;
+ int sas = cfg->spare_area_size << cfg->sector_size_1k;
+ int sectors = cfg->page_size / (512 << cfg->sector_size_1k);
+
+ if (section >= sectors * 2)
+ return -ERANGE;

- layout->eccbytes = req * sectors;
- for (i = 0, idx1 = 0, idx2 = 0; i < sectors; i++) {
- for (j = sas - req; j < sas && idx1 <
- MTD_MAX_ECCPOS_ENTRIES_LARGE; j++, idx1++)
- layout->eccpos[idx1] = i * sas + j;
+ oobregion->offset = (section / 2) * sas;
+
+ if (section & 1) {
+ oobregion->offset += 9;
+ oobregion->length = 7;
+ } else {
+ oobregion->length = 6;

/* First sector of each page may have BBI */
- if (i == 0) {
- if (cfg->page_size == 512 && (sas - req >= 6)) {
- /* Small-page NAND use byte 6 for BBI */
- layout->oobfree[idx2].offset = 0;
- layout->oobfree[idx2].length = 5;
- idx2++;
- if (sas - req > 6) {
- layout->oobfree[idx2].offset = 6;
- layout->oobfree[idx2].length =
- sas - req - 6;
- idx2++;
- }
- } else if (sas > req + 1) {
- layout->oobfree[idx2].offset = i * sas + 1;
- layout->oobfree[idx2].length = sas - req - 1;
- idx2++;
- }
- } else if (sas > req) {
- layout->oobfree[idx2].offset = i * sas;
- layout->oobfree[idx2].length = sas - req;
- idx2++;
+ if (!section) {
+ /*
+ * Small-page NAND use byte 6 for BBI while large-page
+ * NAND use byte 0.
+ */
+ if (cfg->page_size > 512)
+ oobregion->offset++;
+ oobregion->length--;
}
- /* Leave zero-terminated entry for OOBFREE */
- if (idx1 >= MTD_MAX_ECCPOS_ENTRIES_LARGE ||
- idx2 >= MTD_MAX_OOBFREE_ENTRIES_LARGE - 1)
- break;
}

- return layout;
+ return 0;
+}
+
+static const struct mtd_ooblayout_ops brcmnand_hamming_ooblayout_ops = {
+ .ecc = brcmnand_hamming_ooblayout_ecc,
+ .free = brcmnand_hamming_ooblayout_free,
+};
+
+static int brcmnand_bch_ooblayout_ecc(struct mtd_info *mtd, int section,
+ struct mtd_oob_region *oobregion)
+{
+ struct nand_chip *chip = mtd_to_nand(mtd);
+ struct brcmnand_host *host = nand_get_controller_data(chip);
+ struct brcmnand_cfg *cfg = &host->hwcfg;
+ int sas = cfg->spare_area_size << cfg->sector_size_1k;
+ int sectors = cfg->page_size / (512 << cfg->sector_size_1k);
+
+ if (section >= sectors)
+ return -ERANGE;
+
+ oobregion->offset = (section * (sas + 1)) - chip->ecc.bytes;
+ oobregion->length = chip->ecc.bytes;
+
+ return 0;
}

-static struct nand_ecclayout *brcmstb_choose_ecc_layout(
- struct brcmnand_host *host)
+static int brcmnand_bch_ooblayout_free_lp(struct mtd_info *mtd, int section,
+ struct mtd_oob_region *oobregion)
+{
+ struct nand_chip *chip = mtd_to_nand(mtd);
+ struct brcmnand_host *host = nand_get_controller_data(chip);
+ struct brcmnand_cfg *cfg = &host->hwcfg;
+ int sas = cfg->spare_area_size << cfg->sector_size_1k;
+ int sectors = cfg->page_size / (512 << cfg->sector_size_1k);
+
+ if (section >= sectors)
+ return -ERANGE;
+
+ if (sas <= chip->ecc.bytes)
+ return 0;
+
+ oobregion->offset = section * sas;
+ oobregion->length = sas - chip->ecc.bytes;
+
+ if (!section) {
+ oobregion->offset++;
+ oobregion->length--;
+ }
+
+ return 0;
+}
+
+static int brcmnand_bch_ooblayout_free_sp(struct mtd_info *mtd, int section,
+ struct mtd_oob_region *oobregion)
+{
+ struct nand_chip *chip = mtd_to_nand(mtd);
+ struct brcmnand_host *host = nand_get_controller_data(chip);
+ struct brcmnand_cfg *cfg = &host->hwcfg;
+ int sas = cfg->spare_area_size << cfg->sector_size_1k;
+
+ if (section > 1 || sas - chip->ecc.bytes < 6 ||
+ (section && sas - chip->ecc.bytes == 6))
+ return -ERANGE;
+
+ if (!section) {
+ oobregion->offset = 0;
+ oobregion->length = 5;
+ } else {
+ oobregion->offset = 6;
+ oobregion->length = sas - chip->ecc.bytes - 6;
+ }
+
+ return 0;
+}
+
+static const struct mtd_ooblayout_ops brcmnand_bch_lp_ooblayout_ops = {
+ .ecc = brcmnand_bch_ooblayout_ecc,
+ .free = brcmnand_bch_ooblayout_free_lp,
+};
+
+static const struct mtd_ooblayout_ops brcmnand_bch_sp_ooblayout_ops = {
+ .ecc = brcmnand_bch_ooblayout_ecc,
+ .free = brcmnand_bch_ooblayout_free_sp,
+};
+
+static int brcmstb_choose_ecc_layout(struct brcmnand_host *host)
{
- struct nand_ecclayout *layout;
struct brcmnand_cfg *p = &host->hwcfg;
+ struct mtd_info *mtd = nand_to_mtd(&host->chip);
+ struct nand_ecc_ctrl *ecc = &host->chip.ecc;
unsigned int ecc_level = p->ecc_level;
+ int sas = p->spare_area_size << p->sector_size_1k;
+ int sectors = p->page_size / (512 << p->sector_size_1k);

if (p->sector_size_1k)
ecc_level <<= 1;

- layout = brcmnand_create_layout(ecc_level, host);
- if (!layout) {
+ if (is_hamming_ecc(p)) {
+ ecc->bytes = 3 * sectors;
+ mtd_set_ooblayout(mtd, &brcmnand_hamming_ooblayout_ops);
+ return 0;
+ }
+
+ /*
+ * CONTROLLER_VERSION:
+ * < v5.0: ECC_REQ = ceil(BCH_T * 13/8)
+ * >= v5.0: ECC_REQ = ceil(BCH_T * 14/8)
+ * But we will just be conservative.
+ */
+ ecc->bytes = DIV_ROUND_UP(ecc_level * 14, 8);
+ if (p->page_size == 512)
+ mtd_set_ooblayout(mtd, &brcmnand_bch_sp_ooblayout_ops);
+ else
+ mtd_set_ooblayout(mtd, &brcmnand_bch_lp_ooblayout_ops);
+
+ if (ecc->bytes >= sas) {
dev_err(&host->pdev->dev,
- "no proper ecc_layout for this NAND cfg\n");
- return NULL;
+ "error: ECC too large for OOB (ECC bytes %d, spare sector %d)\n",
+ ecc->bytes, sas);
+ return -EINVAL;
}

- return layout;
+ return 0;
}

static void brcmnand_wp(struct mtd_info *mtd, int wp)
@@ -1979,9 +2035,9 @@ static int brcmnand_init_cs(struct brcmnand_host *host, struct device_node *dn)
/* only use our internal HW threshold */
mtd->bitflip_threshold = 1;

- chip->ecc.layout = brcmstb_choose_ecc_layout(host);
- if (!chip->ecc.layout)
- return -ENXIO;
+ ret = brcmstb_choose_ecc_layout(host);
+ if (ret)
+ return ret;

if (nand_scan_tail(mtd))
return -ENXIO;
--
2.1.4