@@ -17,6 +17,12 @@ Required properties:
Optional properties:
- nand-on-flash-bbt: boolean to enable on flash bbt option if not
present false
+ - fsl,use-minimum-ecc: By enabling this boolean property, the gpmi will try
+ to use the datasheet's minimum required ECC provided by
+ the MTD layer (the ecc_strength_ds/ecc_strength_ds fields
+ in the nand_chip{}). So we may have free space in the OOB
+ area by using the minimum ECC, and we may support JFFS2
+ with some SLC NANDs, such as Micron's SLC NAND.
The device tree may optionally contain sub-nodes describing partitions of the
address space. See partition.txt for more detail.
@@ -352,6 +352,10 @@ static int legacy_set_geometry(struct gpmi_nand_data *this)
int common_nfc_set_geometry(struct gpmi_nand_data *this)
{
+ if (of_property_read_bool(this->dev->of_node, "fsl,use-minimum-ecc"))
+ return set_geometry_by_ecc_info(this) ? 0 :
+ legacy_set_geometry(this);
+
return legacy_set_geometry(this) ?
(!set_geometry_by_ecc_info(this)) : 0;
}
In default way, we use the ecc-strength/ecc-step-size calculated by ourselves and use all the OOB area. This patch adds a new property : "fsl,use-minimum-ecc" If we enable it, we will use the datasheet's minimum required ECC provided by the MTD layer (the ecc_strength_ds/ecc_strength_ds fields in the nand_chip{}). So we may have free space in the OOB area by using the minimum ECC, and we may support JFFS2 with some SLC NANDs, such as Micron's SLC NAND. Signed-off-by: Huang Shijie <b32955@freescale.com> --- .../devicetree/bindings/mtd/gpmi-nand.txt | 6 ++++++ drivers/mtd/nand/gpmi-nand/gpmi-nand.c | 4 ++++ 2 files changed, 10 insertions(+), 0 deletions(-)