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Date: Tue, 29 Jan 2013 21:58:09 +0530
From: Vikram Narayanan <vikram186@gmail.com>
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To: Huang Shijie <b32955@freescale.com>
Subject: Re: mtd_oobtest fails with GPMI-NAND
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On 1/29/2013 8:06 AM, Huang Shijie wrote:
>> May I know in what way the driver is restricted for using with other
>> boards?
> The devicetree. Please check the dts file in arch/arm/boot/dts/.
> If there is no dts file for your board, the gpmi will not works very
> well for your board.
> for example, there is arch/arm/boot/dts/imx6q-arm2.dts for the MX6Q-ARM2
> board.

I've a valid dts file for my board which is good enough to probe the 
Toshiba NAND on-board and mount a UBIFS filesystem.

>> You're right and we knew it earlier as the Kernel detects the OOB size
>> as 128 bytes. So, some remaining bytes become unused at the end of
>> each page. i.e., (224-128). Instead of supporting ecc strength as ECC9
>> we end up using ECC8. Should this be a cause for the -74 error?
> no. this is not the cause. even you get the wrong geometry of the nand
> chip. the gpmi still can works.
>
> I think the root cause is the devicetree issue as above.

Something else is causing the issue. Can you give some other pointers 
which can potentially cause this -74 error while mounting?

Regards,
Vikram