diff options
Diffstat (limited to 'drivers/mtd/nand/gpmi-nand/gpmi-nand.c')
| -rw-r--r-- | drivers/mtd/nand/gpmi-nand/gpmi-nand.c | 201 |
1 files changed, 201 insertions, 0 deletions
diff --git a/drivers/mtd/nand/gpmi-nand/gpmi-nand.c b/drivers/mtd/nand/gpmi-nand/gpmi-nand.c index 959cb9b70310..4f3851a24bb2 100644 --- a/drivers/mtd/nand/gpmi-nand/gpmi-nand.c +++ b/drivers/mtd/nand/gpmi-nand/gpmi-nand.c @@ -791,6 +791,7 @@ static void gpmi_free_dma_buffer(struct gpmi_nand_data *this) this->page_buffer_phys); kfree(this->cmd_buffer); kfree(this->data_buffer_dma); + kfree(this->raw_buffer); this->cmd_buffer = NULL; this->data_buffer_dma = NULL; @@ -837,6 +838,9 @@ static int gpmi_alloc_dma_buffer(struct gpmi_nand_data *this) if (!this->page_buffer_virt) goto error_alloc; + this->raw_buffer = kzalloc(mtd->writesize + mtd->oobsize, GFP_KERNEL); + if (!this->raw_buffer) + goto error_alloc; /* Slice up the page buffer. */ this->payload_virt = this->page_buffer_virt; @@ -1347,6 +1351,199 @@ gpmi_ecc_write_oob(struct mtd_info *mtd, struct nand_chip *chip, int page) return status & NAND_STATUS_FAIL ? -EIO : 0; } +/* + * This function reads a NAND page without involving the ECC engine (no HW + * ECC correction). + * The tricky part in the GPMI/BCH controller is that it stores ECC bits + * inline (interleaved with payload DATA), and do not align data chunk on + * byte boundaries. + * We thus need to take care moving the payload data and ECC bits stored in the + * page into the provided buffers, which is why we're using gpmi_copy_bits. + * + * See set_geometry_by_ecc_info inline comments to have a full description + * of the layout used by the GPMI controller. + */ +static int gpmi_ecc_read_page_raw(struct mtd_info *mtd, + struct nand_chip *chip, uint8_t *buf, + int oob_required, int page) +{ + struct gpmi_nand_data *this = chip->priv; + struct bch_geometry *nfc_geo = &this->bch_geometry; + int eccsize = nfc_geo->ecc_chunk_size; + int eccbits = nfc_geo->ecc_strength * nfc_geo->gf_len; + u8 *tmp_buf = this->raw_buffer; + size_t src_bit_off; + size_t oob_bit_off; + size_t oob_byte_off; + uint8_t *oob = chip->oob_poi; + int step; + + chip->read_buf(mtd, tmp_buf, + mtd->writesize + mtd->oobsize); + + /* + * If required, swap the bad block marker and the data stored in the + * metadata section, so that we don't wrongly consider a block as bad. + * + * See the layout description for a detailed explanation on why this + * is needed. + */ + if (this->swap_block_mark) { + u8 swap = tmp_buf[0]; + + tmp_buf[0] = tmp_buf[mtd->writesize]; + tmp_buf[mtd->writesize] = swap; + } + + /* + * Copy the metadata section into the oob buffer (this section is + * guaranteed to be aligned on a byte boundary). + */ + if (oob_required) + memcpy(oob, tmp_buf, nfc_geo->metadata_size); + + oob_bit_off = nfc_geo->metadata_size * 8; + src_bit_off = oob_bit_off; + + /* Extract interleaved payload data and ECC bits */ + for (step = 0; step < nfc_geo->ecc_chunk_count; step++) { + if (buf) + gpmi_copy_bits(buf, step * eccsize * 8, + tmp_buf, src_bit_off, + eccsize * 8); + src_bit_off += eccsize * 8; + + /* Align last ECC block to align a byte boundary */ + if (step == nfc_geo->ecc_chunk_count - 1 && + (oob_bit_off + eccbits) % 8) + eccbits += 8 - ((oob_bit_off + eccbits) % 8); + + if (oob_required) + gpmi_copy_bits(oob, oob_bit_off, + tmp_buf, src_bit_off, + eccbits); + + src_bit_off += eccbits; + oob_bit_off += eccbits; + } + + if (oob_required) { + oob_byte_off = oob_bit_off / 8; + + if (oob_byte_off < mtd->oobsize) + memcpy(oob + oob_byte_off, + tmp_buf + mtd->writesize + oob_byte_off, + mtd->oobsize - oob_byte_off); + } + + return 0; +} + +/* + * This function writes a NAND page without involving the ECC engine (no HW + * ECC generation). + * The tricky part in the GPMI/BCH controller is that it stores ECC bits + * inline (interleaved with payload DATA), and do not align data chunk on + * byte boundaries. + * We thus need to take care moving the OOB area at the right place in the + * final page, which is why we're using gpmi_copy_bits. + * + * See set_geometry_by_ecc_info inline comments to have a full description + * of the layout used by the GPMI controller. + */ +static int gpmi_ecc_write_page_raw(struct mtd_info *mtd, + struct nand_chip *chip, + const uint8_t *buf, + int oob_required) +{ + struct gpmi_nand_data *this = chip->priv; + struct bch_geometry *nfc_geo = &this->bch_geometry; + int eccsize = nfc_geo->ecc_chunk_size; + int eccbits = nfc_geo->ecc_strength * nfc_geo->gf_len; + u8 *tmp_buf = this->raw_buffer; + uint8_t *oob = chip->oob_poi; + size_t dst_bit_off; + size_t oob_bit_off; + size_t oob_byte_off; + int step; + + /* + * Initialize all bits to 1 in case we don't have a buffer for the + * payload or oob data in order to leave unspecified bits of data + * to their initial state. + */ + if (!buf || !oob_required) + memset(tmp_buf, 0xff, mtd->writesize + mtd->oobsize); + + /* + * First copy the metadata section (stored in oob buffer) at the + * beginning of the page, as imposed by the GPMI layout. + */ + memcpy(tmp_buf, oob, nfc_geo->metadata_size); + oob_bit_off = nfc_geo->metadata_size * 8; + dst_bit_off = oob_bit_off; + + /* Interleave payload data and ECC bits */ + for (step = 0; step < nfc_geo->ecc_chunk_count; step++) { + if (buf) + gpmi_copy_bits(tmp_buf, dst_bit_off, + buf, step * eccsize * 8, eccsize * 8); + dst_bit_off += eccsize * 8; + + /* Align last ECC block to align a byte boundary */ + if (step == nfc_geo->ecc_chunk_count - 1 && + (oob_bit_off + eccbits) % 8) + eccbits += 8 - ((oob_bit_off + eccbits) % 8); + + if (oob_required) + gpmi_copy_bits(tmp_buf, dst_bit_off, + oob, oob_bit_off, eccbits); + + dst_bit_off += eccbits; + oob_bit_off += eccbits; + } + + oob_byte_off = oob_bit_off / 8; + + if (oob_required && oob_byte_off < mtd->oobsize) + memcpy(tmp_buf + mtd->writesize + oob_byte_off, + oob + oob_byte_off, mtd->oobsize - oob_byte_off); + + /* + * If required, swap the bad block marker and the first byte of the + * metadata section, so that we don't modify the bad block marker. + * + * See the layout description for a detailed explanation on why this + * is needed. + */ + if (this->swap_block_mark) { + u8 swap = tmp_buf[0]; + + tmp_buf[0] = tmp_buf[mtd->writesize]; + tmp_buf[mtd->writesize] = swap; + } + + chip->write_buf(mtd, tmp_buf, mtd->writesize + mtd->oobsize); + + return 0; +} + +static int gpmi_ecc_read_oob_raw(struct mtd_info *mtd, struct nand_chip *chip, + int page) +{ + chip->cmdfunc(mtd, NAND_CMD_READ0, 0, page); + + return gpmi_ecc_read_page_raw(mtd, chip, NULL, 1, page); +} + +static int gpmi_ecc_write_oob_raw(struct mtd_info *mtd, struct nand_chip *chip, + int page) +{ + chip->cmdfunc(mtd, NAND_CMD_SEQIN, 0, page); + + return gpmi_ecc_write_page_raw(mtd, chip, NULL, 1); +} + static int gpmi_block_markbad(struct mtd_info *mtd, loff_t ofs) { struct nand_chip *chip = mtd->priv; @@ -1664,6 +1861,10 @@ static int gpmi_init_last(struct gpmi_nand_data *this) ecc->write_page = gpmi_ecc_write_page; ecc->read_oob = gpmi_ecc_read_oob; ecc->write_oob = gpmi_ecc_write_oob; + ecc->read_page_raw = gpmi_ecc_read_page_raw; + ecc->write_page_raw = gpmi_ecc_write_page_raw; + ecc->read_oob_raw = gpmi_ecc_read_oob_raw; + ecc->write_oob_raw = gpmi_ecc_write_oob_raw; ecc->mode = NAND_ECC_HW; ecc->size = bch_geo->ecc_chunk_size; ecc->strength = bch_geo->ecc_strength; |
