Add HW ECC support for the sunxi NAND Flash Controller.
Signed-off-by: Boris BREZILLON <b.brezillon.dev@xxxxxxxxx>
---
drivers/mtd/nand/sunxi_nand.c | 279 +++++++++++++++++++++++++++++++++++++++--
1 file changed, 266 insertions(+), 13 deletions(-)
diff --git a/drivers/mtd/nand/sunxi_nand.c b/drivers/mtd/nand/sunxi_nand.c
index 1014b2a..b90268f 100644
--- a/drivers/mtd/nand/sunxi_nand.c
+++ b/drivers/mtd/nand/sunxi_nand.c
@@ -163,6 +163,11 @@ struct sunxi_nand_chip_sel {
#define DEFAULT_NAME_FORMAT "nand@%d"
#define MAX_NAME_SIZE (sizeof("nand@") + 2)
+struct sunxi_nand_hw_ecc {
+ int mode;
+ struct nand_ecclayout layout;
+};
+
struct sunxi_nand_chip {
struct list_head node;
struct nand_chip nand;
@@ -402,6 +407,126 @@ static void sunxi_nfc_cmd_ctrl(struct mtd_info *mtd, int dat,
sunxi_nfc_wait_int(nfc, NFC_CMD_INT_FLAG, 0);
}
+static int sunxi_nfc_hwecc_read_page(struct mtd_info *mtd,
+ struct nand_chip *chip, uint8_t *buf,
+ int oob_required, int page)
+{
+ struct sunxi_nand_chip *sunxi_nand = to_sunxi_nand(mtd);
+ struct sunxi_nfc *nfc = to_sunxi_nfc(sunxi_nand->nand.controller);
+ struct nand_ecc_ctrl *ecc = &chip->ecc;
+ struct nand_ecclayout *layout = ecc->layout;
+ struct sunxi_nand_hw_ecc *data = ecc->priv;
+ unsigned int max_bitflips = 0;
+ int offset;
+ u32 tmp;
+ int i;
+
+ tmp = readl(nfc->regs + NFC_REG_ECC_CTL);
+ tmp &= ~(NFC_ECC_MODE | NFC_ECC_PIPELINE | NFC_ECC_BLOCK_SIZE |
+ NFC_ECC_BLOCK_SIZE);
+ tmp |= NFC_ECC_EN | (data->mode << NFC_ECC_MODE_SHIFT);
+ writel(tmp, nfc->regs + NFC_REG_ECC_CTL);
+
+ for (i = 0; i < mtd->writesize / ecc->size; i++) {
+ if (i)
+ chip->cmdfunc(mtd, NAND_CMD_RNDOUT, i * ecc->size, -1);
+ chip->read_buf(mtd, NULL, chip->ecc.size);
+ offset = mtd->writesize + layout->eccpos[i * ecc->bytes] - 4;
+ chip->cmdfunc(mtd, NAND_CMD_RNDOUT, offset, -1);
+ while ((readl(nfc->regs + NFC_REG_ST) & NFC_CMD_FIFO_STATUS))
+ ;
+ tmp = NFC_DATA_TRANS | NFC_DATA_SWAP_METHOD | (1 << 30);
+ writel(tmp, nfc->regs + NFC_REG_CMD);
+ sunxi_nfc_wait_int(nfc, NFC_CMD_INT_FLAG, 0);
+ memcpy_fromio(buf + (i * ecc->size), nfc->regs + NFC_RAM0_BASE,
+ chip->ecc.size);
+
+ if (readl(nfc->regs + NFC_REG_ECC_ST) & 0x1) {
+ mtd->ecc_stats.failed++;
+ } else {
+ tmp = readl(nfc->regs + NFC_REG_ECC_CNT0) & 0xff;
+ mtd->ecc_stats.corrected += tmp;
+ max_bitflips = max_t(unsigned int, max_bitflips, tmp);
+ }
+ }
+
+ if (oob_required) {
+ chip->cmdfunc(mtd, NAND_CMD_RNDOUT, mtd->writesize, -1);
+ chip->read_buf(mtd, chip->oob_poi, mtd->oobsize);
+ }
+
+ tmp = readl(nfc->regs + NFC_REG_ECC_CTL);
+ tmp &= ~NFC_ECC_EN;
+
+ writel(tmp, nfc->regs + NFC_REG_ECC_CTL);
+
+ return max_bitflips;
+}
+
+static int sunxi_nfc_hwecc_write_page(struct mtd_info *mtd,
+ struct nand_chip *chip,
+ const uint8_t *buf,
+ int oob_required)
+{
+ struct sunxi_nand_chip *sunxi_nand = to_sunxi_nand(mtd);
+ struct sunxi_nfc *nfc = to_sunxi_nfc(sunxi_nand->nand.controller);
+ struct nand_ecc_ctrl *ecc = &chip->ecc;
+ struct nand_ecclayout *layout = ecc->layout;
+ struct sunxi_nand_hw_ecc *data = ecc->priv;
+ int offset;
+ u32 tmp;
+ int i;
+ int j;
+
+ tmp = readl(nfc->regs + NFC_REG_ECC_CTL);
+ tmp &= ~(NFC_ECC_MODE | NFC_ECC_PIPELINE | NFC_ECC_BLOCK_SIZE |
+ NFC_ECC_BLOCK_SIZE);
+ tmp |= NFC_ECC_EN | (data->mode << NFC_ECC_MODE_SHIFT);
+
+ writel(tmp, nfc->regs + NFC_REG_ECC_CTL);
+
+ for (i = 0; i < mtd->writesize / ecc->size; i++) {
+ if (i)
+ chip->cmdfunc(mtd, NAND_CMD_RNDIN, i * ecc->size, -1);
+
+ chip->write_buf(mtd, buf + (i * ecc->size), ecc->size);
+ offset = mtd->writesize + layout->eccpos[i * ecc->bytes] - 4;
+ chip->cmdfunc(mtd, NAND_CMD_RNDIN, offset, -1);
+ while ((readl(nfc->regs + NFC_REG_ST) & NFC_CMD_FIFO_STATUS))
+ ;
+
+ /* Fill OOB data in */
+ for (j = 0; j < 4; j++) {
+ if (oob_required) {
+ offset = layout->eccpos[i * ecc->size] - 4;
+ writeb(chip->oob_poi[offset + j],
+ nfc->regs + NFC_REG_USER_DATA_BASE + j);
+ } else {
+ writeb(0xff,
+ nfc->regs + NFC_REG_USER_DATA_BASE + j);
+ }
+ }
+
+ tmp = NFC_DATA_TRANS | NFC_DATA_SWAP_METHOD |
+ NFC_ACCESS_DIR | (1 << 30);
+ writel(tmp, nfc->regs + NFC_REG_CMD);
+ sunxi_nfc_wait_int(nfc, NFC_CMD_INT_FLAG, 0);
+ }
+
+ if (oob_required && chip->ecc.layout->oobfree[0].length > 2) {
+ chip->cmdfunc(mtd, NAND_CMD_RNDIN, mtd->writesize, -1);
+ chip->write_buf(mtd, chip->oob_poi,
+ chip->ecc.layout->oobfree[0].length - 2);
+ }
+
+ tmp = readl(nfc->regs + NFC_REG_ECC_CTL);
+ tmp &= ~(NFC_ECC_EN | NFC_ECC_PIPELINE);
+
+ writel(tmp, nfc->regs + NFC_REG_ECC_CTL);
+
+ return 0;
+}
+
static int sunxi_nand_chip_set_timings(struct sunxi_nand_chip *chip,
const struct nand_sdr_timings *timings)
{
@@ -504,6 +629,144 @@ static int sunxi_nand_chip_init_timings(struct sunxi_nand_chip *chip,
return sunxi_nand_chip_set_timings(chip, timings);
}
+static int sunxi_nand_chip_hwecc_init(struct device *dev,
+ struct sunxi_nand_chip *chip,
+ struct mtd_info *mtd,
+ struct device_node *np)
+{
+ struct nand_chip *nand = &chip->nand;
+ struct nand_ecc_ctrl *ecc = &nand->ecc;
+ struct sunxi_nand_hw_ecc *data;
+ struct nand_ecclayout *layout;
+ int nsectors;
+ int i;
+ int j;
+
+ data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ ecc->read_page = sunxi_nfc_hwecc_read_page;
+ ecc->write_page = sunxi_nfc_hwecc_write_page;
+
+ if (nand->ecc_strength_ds <= 16) {
+ nand->ecc_strength_ds = 16;
+ data->mode = 0;
+ } else if (nand->ecc_strength_ds <= 24) {
+ nand->ecc_strength_ds = 24;
+ data->mode = 1;
+ } else if (nand->ecc_strength_ds <= 28) {
+ nand->ecc_strength_ds = 28;
+ data->mode = 2;
+ } else if (nand->ecc_strength_ds <= 32) {
+ nand->ecc_strength_ds = 32;
+ data->mode = 3;
+ } else if (nand->ecc_strength_ds <= 40) {
+ nand->ecc_strength_ds = 40;
+ data->mode = 4;
+ } else if (nand->ecc_strength_ds <= 48) {
+ nand->ecc_strength_ds = 48;
+ data->mode = 5;
+ } else if (nand->ecc_strength_ds <= 56) {
+ nand->ecc_strength_ds = 56;
+ data->mode = 6;
+ } else if (nand->ecc_strength_ds <= 60) {
+ nand->ecc_strength_ds = 60;
+ data->mode = 7;
+ } else if (nand->ecc_strength_ds <= 64) {
+ nand->ecc_strength_ds = 64;
+ data->mode = 8;
+ } else {
+ dev_err(dev, "unsupported strength\n");
+ return -ENOTSUPP;
+ }
+
+ /* HW ECC always request ECC bytes for 1024 bytes blocks */
+ ecc->bytes = ((nand->ecc_strength_ds * fls(8 * 1024)) + 7) / 8;
+
+ /* HW ECC always work with even numbers of ECC bytes */
+ if (ecc->bytes % 2)
+ ecc->bytes++;
+ ecc->strength = nand->ecc_strength_ds;
+ ecc->size = nand->ecc_step_ds;
+
+ layout = &data->layout;
+ nsectors = mtd->writesize / ecc->size;
+
+ if (mtd->oobsize < ((ecc->bytes + 4) * nsectors))
+ return -EINVAL;
+
+ layout->eccbytes = (ecc->bytes * nsectors);
+
+ /*
+ * The first 2 bytes are used for BB markers.
+ * We merge the 4 user available bytes from HW ECC with this
+ * first section, hence why the + 2 operation (- 2 + 4).
+ */
+ layout->oobfree[0].length = mtd->oobsize + 2 -
+ ((ecc->bytes + 4) * nsectors);
+ layout->oobfree[0].offset = 2;
+ for (i = 0; i < nsectors; i++) {
+ /*
+ * The first 4 ECC block bytes are already counted in the first
+ * obbfree entry.
+ */
+ if (i) {
+ layout->oobfree[i].offset =
+ layout->oobfree[i - 1].offset +
+ layout->oobfree[i - 1].length +
+ ecc->bytes;
+ layout->oobfree[i].length = 4;
+ }
+
+ for (j = 0; j < ecc->bytes; j++)
+ layout->eccpos[(ecc->bytes * i) + j] =
+ layout->oobfree[i].offset +
+ layout->oobfree[i].length + j;
+ }
+
+ ecc->layout = layout;
+ ecc->priv = data;
+
+ return 0;
+}
+
+static int sunxi_nand_chip_ecc_init(struct device *dev,
+ struct sunxi_nand_chip *chip,
+ struct mtd_info *mtd,
+ struct device_node *np)
+{
+ struct nand_chip *nand = &chip->nand;
+ u32 strength;
+ u32 blk_size;
+ int ret;
+
+ nand->ecc.mode = of_get_nand_ecc_mode(np);
+
+ if (!of_get_nand_ecc_level(np, &strength, &blk_size)) {
+ nand->ecc_step_ds = blk_size;
+ nand->ecc_strength_ds = strength;
+ }
+
+ switch (nand->ecc.mode) {
+ case NAND_ECC_SOFT_BCH:
+ nand->ecc.size = nand->ecc_step_ds;
+ nand->ecc.bytes = ((nand->ecc_strength_ds *
+ fls(8 * nand->ecc_step_ds)) + 7) / 8;
+ break;
+ case NAND_ECC_HW:
+ ret = sunxi_nand_chip_hwecc_init(dev, chip, mtd, np);
+ if (ret)
+ return ret;
+ break;
+ case NAND_ECC_NONE:
+ default:
+ break;
+ }
+
+ return 0;
+}
+
static int sunxi_nand_chip_init(struct device *dev, struct sunxi_nfc *nfc,
struct device_node *np)
{
@@ -512,8 +775,6 @@ static int sunxi_nand_chip_init(struct device *dev, struct sunxi_nfc *nfc,
struct mtd_part_parser_data ppdata;
struct mtd_info *mtd;
struct nand_chip *nand;
- u32 strength;
- u32 blk_size;
int nsels;
int ret;
int i;
@@ -586,7 +847,6 @@ static int sunxi_nand_chip_init(struct device *dev, struct sunxi_nfc *nfc,
nand->write_buf = sunxi_nfc_write_buf;
nand->read_byte = sunxi_nfc_read_byte;
- nand->ecc.mode = of_get_nand_ecc_mode(np);
if (of_get_nand_on_flash_bbt(np))
nand->bbt_options |= NAND_BBT_USE_FLASH;
@@ -602,16 +862,9 @@ static int sunxi_nand_chip_init(struct device *dev, struct sunxi_nfc *nfc,
if (ret)
return ret;
- if (nand->ecc.mode == NAND_ECC_SOFT_BCH) {
- if (!of_get_nand_ecc_level(np, &strength, &blk_size)) {
- nand->ecc_step_ds = blk_size;
- nand->ecc_strength_ds = strength;
- }
-
- nand->ecc.size = nand->ecc_step_ds;
- nand->ecc.bytes = (((nand->ecc_strength_ds *
- fls(8 * nand->ecc_step_ds)) + 7) / 8);
- }
+ ret = sunxi_nand_chip_ecc_init(dev, chip, mtd, np);
+ if (ret)
+ return ret;
ret = nand_scan_tail(mtd);
if (ret)
--
1.7.9.5
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