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Date: Tue, 1 Apr 2014 15:49:18 +0200
From: Gerhard Sittig <gsi@denx.de>
To: Brian Norris <computersforpeace@gmail.com>
Subject: Re: [RFC] mtd: nand: Preparatory patch for adding on-die ECC
 controller support. This patch adds NAND_ECC_HW_ON_DIE and all other changes
 to generic code.
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On Tue, 2014-04-01 at 02:12 -0700, Brian Norris wrote:
> 
> BTW, do these flash power on in any particular default mode? Can you
> order versions that have on-die ECC enabeld/disabled by default? Is that
> perhaps what the READ_ID "Internal ECC" flag actually means
> (disabled/enabled by default)?

According to the datasheet the chips come out of RESET with
on-die-ECC disabled.  The setup that I have seen does enable the
in-chip feature within an early loader.  Subsequently running
bootloaders and OSes (here: U-Boot and Linux) find the chip with
on-die-ECC enabled.

I understand that READ_ID will tell you whether on-die-ECC is
supported by the chip.  The GETFEATURE request tells you whether
it's enabled.  And SETFEATURE allows you to control whether it's
enabled or disabled.


virtually yours
Gerhard Sittig
-- 
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