Re: mtd_oobtest fails with GPMI-NAND

[Huang Shijie <b32955@freescale.com>]

于 2013年01月29日 10:26, Vikram Narayanan 写道:
> On 1/29/2013 7:36 AM, Huang Shijie wrote:
>> 于 2013年01月29日 01:04, Vikram Narayanan 写道:
>>> On 1/28/2013 8:50 AM, Huang Shijie wrote:
>>>> 于 2013年01月28日 10:39, Vikram Narayanan 写道:
>>>>> Hello Huang,
>>>>>
>>>>> On 1/21/2013 7:42 AM, Huang Shijie wrote:
>>>>>> 于 2013年01月19日 00:52, Vikram Narayanan 写道:
>>>>>>> Hi,
>>>>>>>
>>>>>>> When I try to run the mtd_oobtest on an i.Mx6Q board, it results 
>>>>>>> in a
>> Which mx6q' board are you using? the mx6q-arm2 or mx6q-ard?
>
> I'm using a custom board.
ok.
>
>> The kernel only supports the mx6q-arm2 now.
>
> 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.

>
>>>
>>> Toshiba, 4 Gbit, (4096 +224) bytes ×64 pages ×2048blocks
>>
>> The Toshiba's nand is not well supported by the kernel.
>> Are you sure the kernel parse out the correct geometry for the toshiba's
>> nand?
>> Please recheck the page size and oob size with "mtdinfo /dev/mtd0".
>>
>
> 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.

thanks
Huang Shijie
>
> Regards,
> Vikram
>