Hi Mason, Mason Yang <masonccyang@xxxxxxxxxxx> wrote on Thu, 24 Oct 2019 15:40:06 +0800: > Macronix NANDs support randomizer operation for user data scrambled, > which can be enabled with a SET_FEATURE. > > User data written to the NAND device without randomizer is still readable > after randomizer function enabled. > The penalty of randomizer are subpage accesses prohibited and more time > period is needed in program operation and entering deep power-down mode. > i.e., tPROG 300us to 340us(randomizer enabled) > > For more high-reliability concern, if subpage write not available with > hardware ECC and then to enable randomizer is recommended by default. > Driver checks byte 167 of Vendor Blocks in ONFI parameter page table > to see if this high-reliability function is supported. By adding a new > specific DT property in children nodes to enable randomizer function. > > Signed-off-by: Mason Yang <masonccyang@xxxxxxxxxxx> > --- > drivers/mtd/nand/raw/nand_macronix.c | 69 ++++++++++++++++++++++++++++++++++++ > 1 file changed, 69 insertions(+) > > diff --git a/drivers/mtd/nand/raw/nand_macronix.c b/drivers/mtd/nand/raw/nand_macronix.c > index 58511ae..89101fa 100644 > --- a/drivers/mtd/nand/raw/nand_macronix.c > +++ b/drivers/mtd/nand/raw/nand_macronix.c > @@ -11,6 +11,14 @@ > #define MACRONIX_READ_RETRY_BIT BIT(0) > #define MACRONIX_NUM_READ_RETRY_MODES 6 > > +#define MACRONIX_RANDOMIZER_BIT BIT(1) > +#define ONFI_FEATURE_ADDR_MXIC_RANDOMIZER 0xB0 > +#define ENPGM BIT(0) > +#define RANDEN BIT(1) > +#define RANDOPT BIT(2) I forgot: please be consistent with the naming. Thanks, Miquèl
