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Date: Thu, 20 Mar 2014 14:39:22 -0300
From: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
To: linux-mtd@lists.infradead.org, Brian Norris <computersforpeace@gmail.com>
Subject: Re: [PATCH 1/4] mtd: nand: pxa3xx: Normalize ECC strength for ECC
 scheme selection
Message-ID: <20140320173922.GA1142@arch.cereza>
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Cc: Lior Amsalem <alior@marvell.com>,
 Thomas Petazzoni <thomas.petazzoni@free-electrons.com>,
 Tawfik Bayouk <tawfik@marvell.com>, Seif Mazareeb <seif@marvell.com>,
 Simon Guinot <sguinot@lacie.com>,
 Gregory Clement <gregory.clement@free-electrons.com>, Willy Tarreau <w@1wt.eu>
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On Mar 17, Ezequiel Garcia wrote:
> @@ -1525,8 +1524,8 @@ KEEP_CONFIG:
>  		ecc_step = 512;
>  	}
>  
> -	ret = pxa_ecc_init(info, &chip->ecc, ecc_strength,
> -			   ecc_step, mtd->writesize);
> +	ret = pxa_ecc_init(info, &chip->ecc, (ecc_strength * ecc_step) / 512,
> +			   mtd->writesize);

After a test report from Simon Guinot we found this normalization is horribly
wrong. It should be: (ecc_strength * 512) / ecc_step. I'll prepare a v2 and
make sure to test it properly this time!
-- 
Ezequiel García, Free Electrons
Embedded Linux, Kernel and Android Engineering
http://free-electrons.com