@@ -30,6 +30,9 @@ Optional properties:
command is asserted. Zero means one cycle, 255 means 256
cycles.
- bank: default NAND bank to use (0-3 are valid, 0 is the default).
+- nand-ecc-mode : see nand.txt
+- nand-ecc-strength : see nand.txt
+- nand-ecc-step-size : see nand.txt
Example:
@@ -1023,12 +1023,17 @@ static int __init fsmc_nand_probe(struct platform_device *pdev)
nand->cmd_ctrl = fsmc_cmd_ctrl;
nand->chip_delay = 30;
+ /*
+ * Setup default ECC mode. nand_dt_init() called from nand_scan_init()
+ * can overwrite this value if the DT provides a different value.
+ */
nand->ecc.mode = NAND_ECC_HW;
nand->ecc.hwctl = fsmc_enable_hwecc;
nand->ecc.size = 512;
nand->options = pdata->options;
nand->select_chip = fsmc_select_chip;
nand->badblockbits = 7;
+ nand->dn = np;
if (pdata->width == FSMC_NAND_BW16)
nand->options |= NAND_BUSWIDTH_16;
@@ -1070,11 +1075,6 @@ static int __init fsmc_nand_probe(struct platform_device *pdev)
nand->ecc.correct = fsmc_bch8_correct_data;
nand->ecc.bytes = 13;
nand->ecc.strength = 8;
- } else {
- nand->ecc.calculate = fsmc_read_hwecc_ecc1;
- nand->ecc.correct = nand_correct_data;
- nand->ecc.bytes = 3;
- nand->ecc.strength = 1;
}
/*
@@ -1115,22 +1115,47 @@ static int __init fsmc_nand_probe(struct platform_device *pdev)
goto err_probe;
}
} else {
- switch (host->mtd.oobsize) {
- case 16:
- nand->ecc.layout = &fsmc_ecc1_16_layout;
+ switch (nand->ecc.mode) {
+ case NAND_ECC_HW:
+ dev_info(&pdev->dev, "Using 1-bit HW ECC scheme\n");
+ nand->ecc.calculate = fsmc_read_hwecc_ecc1;
+ nand->ecc.correct = nand_correct_data;
+ nand->ecc.bytes = 3;
+ nand->ecc.strength = 1;
break;
- case 64:
- nand->ecc.layout = &fsmc_ecc1_64_layout;
- break;
- case 128:
- nand->ecc.layout = &fsmc_ecc1_128_layout;
+
+ case NAND_ECC_SOFT_BCH:
+ dev_info(&pdev->dev, "Using 4-bit SW BCH ECC scheme\n");
break;
+
default:
- dev_warn(&pdev->dev, "No oob scheme defined for oobsize %d\n",
- mtd->oobsize);
- ret = -EINVAL;
+ dev_err(&pdev->dev, "Unsupported ECC mode!\n");
goto err_probe;
}
+
+ /*
+ * Don't set layout for BCH4 SW ECC. This will be
+ * generated later in nand_bch_init() later.
+ */
+ if (nand->ecc.mode != NAND_ECC_SOFT_BCH) {
+ switch (host->mtd.oobsize) {
+ case 16:
+ nand->ecc.layout = &fsmc_ecc1_16_layout;
+ break;
+ case 64:
+ nand->ecc.layout = &fsmc_ecc1_64_layout;
+ break;
+ case 128:
+ nand->ecc.layout = &fsmc_ecc1_128_layout;
+ break;
+ default:
+ dev_warn(&pdev->dev,
+ "No oob scheme defined for oobsize %d\n",
+ mtd->oobsize);
+ ret = -EINVAL;
+ goto err_probe;
+ }
+ }
}
/* Second stage of scan to fill MTD data-structures */
This patch adds support for 4-bit ECC BCH4 for the SPEAr600 SoC. This can be used by boards equipped with a NAND chip that requires 4-bit ECC strength. The SPEAr600 HW ECC only supports 1-bit ECC strength. To enable SW BCH4, you need to specify this in your nand controller DT node: nand-ecc-mode = "soft_bch"; nand-ecc-strength = <4>; nand-ecc-step-size = <512>; Tested on a custom SPEAr600 board. Signed-off-by: Stefan Roese <sr@denx.de> Cc: Linus Walleij <linus.walleij@linaro.org> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: Brian Norris <computersforpeace@gmail.com> --- v2: - Used nand_dt_init() to parse the ECC properties - Added optional ECC bindings documentation - Removed whitespace change from this patch, moved to a separate patch - Removed setting of nand_bch_calculate_ecc / nand_bch_correct_data as its already done in nand_scan_tail() - Moved ECC checking after nand_scan_ident() - Removed addition of ecc_mode to platform_data as its not needed anymore .../devicetree/bindings/mtd/fsmc-nand.txt | 3 ++ drivers/mtd/nand/fsmc_nand.c | 57 ++++++++++++++++------ 2 files changed, 44 insertions(+), 16 deletions(-)