Re: [PATCH] Add support for Macronix NAND randomizer

From: Miquel Raynal
Date: Sat Aug 24 2019 - 07:03:43 EST

Hi Mason,

Mason Yang <masonccyang@xxxxxxxxxxx> wrote on Tue, 20 Aug 2019 13:53:48

> 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 NOP = 1 instead of NOP = 4 and more time period

please don't use 'NOP' here, use 'subpage accesses' instead, otherwise
people might not understand what it means while it has a real impact.

> is needed in program operation and entering deep power-down mode.
> i.e., tPROG 300us to 340us(randomizer enabled)
> If subpage write not available with hardware ECC, for example,
> NAND chip options NAND_NO_SUBPAGE_WRITE be set in driver and
> randomizer function is recommended for high-reliability.
> Driver checks byte 167 of Vendor Blocks in ONFI parameter page table
> to see if this high-reliability function is supported.

You did not flagged this patch as a v2 and forgot about the changelog.
You did not listen to our comments in the last version neither. I was
open to a solution with a specific DT property for warned users but I
don't see it coming.