mtd_oobtest fails with GPMI-NAND

[Huang Shijie]

On Sat, Feb 2, 2013 at 3:42 PM, Huang Shijie <shijie8 at gmail.com> wrote:
> On Sat, Feb 2, 2013 at 2:41 PM, Vikram Narayanan <vikram186 at gmail.com> wrote:
>> On 1/30/2013 7:57 AM, Huang Shijie wrote:
>>>
>>> 于 2013年01月30日 00:28, Vikram Narayanan 写道:
>>>>
>>>> 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.
>>>
>>> could you tell the dts file for your board?
>>> are you sure the pinmux settings are right?
>>
>>
>> I'm using the same pinumx settings mentioned in the file
>> "arch/arm/boot/dts/imx6q.dtsi". Hope that is right.
>>
>>
>
> The pinmux  was  set for the arm2 board. So i am  not sure it is
> suitable for your board.
>
> i suggest you check this carefully with your board.
>
>
>>>>
>>>>>> 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?
>>>
>>> the -74 error is the EBADMSG, it's caused by the uncorrectable ECC
>>> failure.
>>> There are many reasons can cause this error:
>>>     [1] the pinmux setting is not right, the gpmi does not works well.
>>
>>
>> As said above, my pinmux settings are right. GPMI detects my NAND, does
>> read/write/erase/mount. At times I'm seeing this -74 issue. Sometimes this
>> error goes off in the next reboot.
>>
>>
>>>     [2] the wrong setting of BCH. for example, the page size is 8K, you
>>> set 4k to BCH.
>>>         so you can set the correct nand geometry parameters for your
>>> nand chip firstly, and then do the debug.
>>
>>
>> From the driver I understood that the geometry are determined according to
>> the data from the read_id bytes. mtd layer detects my NAND as 4K page-sized.
>> So, this shouldn't be a problem I guess.
>>
> yes. i agree.
>
>>>     [3] timings.
>>
>>
>> Should I tweak something specific according to the NAND device that I have?
>> Can you give more hints please?
>>
> Could you make sure that the page write is good?
> You can test it with the mtd_torture.c

sorry.  it should be the mtd_torturetest.c.


>
> thanks
> Huang Shijie
>
>
>
>> Thanks,
>>
>> Vikram
>>
>> ______________________________________________________
>> Linux MTD discussion mailing list
>> http://lists.infradead.org/mailman/listinfo/linux-mtd/