diff options
| -rw-r--r-- | drivers/mtd/nand/gpmi-nand/gpmi-nand.c | 96 |
1 files changed, 96 insertions, 0 deletions
diff --git a/drivers/mtd/nand/gpmi-nand/gpmi-nand.c b/drivers/mtd/nand/gpmi-nand/gpmi-nand.c index 5aaa7f541ea1..bb77f750e75a 100644 --- a/drivers/mtd/nand/gpmi-nand/gpmi-nand.c +++ b/drivers/mtd/nand/gpmi-nand/gpmi-nand.c @@ -27,6 +27,7 @@ #include <linux/of_device.h> #include <linux/of_mtd.h> #include "gpmi-nand.h" +#include "bch-regs.h" /* Resource names for the GPMI NAND driver. */ #define GPMI_NAND_GPMI_REGS_ADDR_RES_NAME "gpmi-nand" @@ -1049,6 +1050,90 @@ static int gpmi_ecc_read_page(struct mtd_info *mtd, struct nand_chip *chip, return max_bitflips; } +/* Fake a virtual small page for the subpage read */ +static int gpmi_ecc_read_subpage(struct mtd_info *mtd, struct nand_chip *chip, + uint32_t offs, uint32_t len, uint8_t *buf, int page) +{ + struct gpmi_nand_data *this = chip->priv; + void __iomem *bch_regs = this->resources.bch_regs; + struct bch_geometry old_geo = this->bch_geometry; + struct bch_geometry *geo = &this->bch_geometry; + int size = chip->ecc.size; /* ECC chunk size */ + int meta, n, page_size; + u32 r1_old, r2_old, r1_new, r2_new; + unsigned int max_bitflips; + int first, last, marker_pos; + int ecc_parity_size; + int col = 0; + + /* The size of ECC parity */ + ecc_parity_size = geo->gf_len * geo->ecc_strength / 8; + + /* Align it with the chunk size */ + first = offs / size; + last = (offs + len - 1) / size; + + /* + * Find the chunk which contains the Block Marker. If this chunk is + * in the range of [first, last], we have to read out the whole page. + * Why? since we had swapped the data at the position of Block Marker + * to the metadata which is bound with the chunk 0. + */ + marker_pos = geo->block_mark_byte_offset / size; + if (last >= marker_pos && first <= marker_pos) { + dev_dbg(this->dev, "page:%d, first:%d, last:%d, marker at:%d\n", + page, first, last, marker_pos); + return gpmi_ecc_read_page(mtd, chip, buf, 0, page); + } + + meta = geo->metadata_size; + if (first) { + col = meta + (size + ecc_parity_size) * first; + chip->cmdfunc(mtd, NAND_CMD_RNDOUT, col, -1); + + meta = 0; + buf = buf + first * size; + } + + /* Save the old environment */ + r1_old = r1_new = readl(bch_regs + HW_BCH_FLASH0LAYOUT0); + r2_old = r2_new = readl(bch_regs + HW_BCH_FLASH0LAYOUT1); + + /* change the BCH registers and bch_geometry{} */ + n = last - first + 1; + page_size = meta + (size + ecc_parity_size) * n; + + r1_new &= ~(BM_BCH_FLASH0LAYOUT0_NBLOCKS | + BM_BCH_FLASH0LAYOUT0_META_SIZE); + r1_new |= BF_BCH_FLASH0LAYOUT0_NBLOCKS(n - 1) + | BF_BCH_FLASH0LAYOUT0_META_SIZE(meta); + writel(r1_new, bch_regs + HW_BCH_FLASH0LAYOUT0); + + r2_new &= ~BM_BCH_FLASH0LAYOUT1_PAGE_SIZE; + r2_new |= BF_BCH_FLASH0LAYOUT1_PAGE_SIZE(page_size); + writel(r2_new, bch_regs + HW_BCH_FLASH0LAYOUT1); + + geo->ecc_chunk_count = n; + geo->payload_size = n * size; + geo->page_size = page_size; + geo->auxiliary_status_offset = ALIGN(meta, 4); + + dev_dbg(this->dev, "page:%d(%d:%d)%d, chunk:(%d:%d), BCH PG size:%d\n", + page, offs, len, col, first, n, page_size); + + /* Read the subpage now */ + this->swap_block_mark = false; + max_bitflips = gpmi_ecc_read_page(mtd, chip, buf, 0, page); + + /* Restore */ + writel(r1_old, bch_regs + HW_BCH_FLASH0LAYOUT0); + writel(r2_old, bch_regs + HW_BCH_FLASH0LAYOUT1); + this->bch_geometry = old_geo; + this->swap_block_mark = true; + + return max_bitflips; +} + static int gpmi_ecc_write_page(struct mtd_info *mtd, struct nand_chip *chip, const uint8_t *buf, int oob_required) { @@ -1566,6 +1651,17 @@ static int gpmi_init_last(struct gpmi_nand_data *this) ecc->layout = &gpmi_hw_ecclayout; /* + * We only enable the subpage read when: + * (1) the chip is imx6, and + * (2) the size of the ECC parity is byte aligned. + */ + if (GPMI_IS_MX6Q(this) && + ((bch_geo->gf_len * bch_geo->ecc_strength) % 8) == 0) { + ecc->read_subpage = gpmi_ecc_read_subpage; + chip->options |= NAND_SUBPAGE_READ; + } + + /* * Can we enable the extra features? such as EDO or Sync mode. * * We do not check the return value now. That's means if we fail in |