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path: root/drivers/mtd/nand/gpmi-nand/gpmi-nand.c
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Diffstat (limited to 'drivers/mtd/nand/gpmi-nand/gpmi-nand.c')
-rw-r--r--drivers/mtd/nand/gpmi-nand/gpmi-nand.c201
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;
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