[U-Boot] Problem with attaching UBI partition

[Stefan Roese <sr@denx.de>]

Hi Chin Liang,

On 02.03.2016 13:24, Chin Liang See wrote:
>> On 01.03.2016 14:38, Chin Liang See wrote:
>>> On Tue, 2016-03-01 at 08:23 +0100, Stefan Roese wrote:
>>>> On 01.03.2016 07:53, Chin Liang See wrote:
>>>>> On Mon, 2016-02-29 at 23:55 +0100, Marek Vasut wrote:
>>>>>> On 02/24/2016 09:59 AM, Bakhvalov, Denis (Nokia - PL/Wroclaw)
>>>>>> wrote:
>>>>>>> Hello Heiko,
>>>>>>>
>>>>>>>> Which U-Boot version? Which board?
>>>>>>>
>>>>>>> This is U-Boot v2016.03-rc1. I have custom board with
>>>>>>> socfpga
>>>>>>> Arria5
>>>>>>> onboard.
>>>>>>>
>>>>>>>> Where does this leading 0xff come from? There seems a
>>>>>>>> problem
>>>>>>>> with
>>>>>>>> your spi nor flash driver?
>>>>>>>
>>>>>>> Yes, you're right. I have problems with the driver. As I
>>>>>>> mentioned
>>>>>>> in
>>>>>>> previous mail when I read the contents from the flash some
>>>>>>> data
>>>>>>> is
>>>>>>> corrupted.
>>>>>>>
>>>>>>> How to find out if the problem is because U-Boot has no
>>>>>>> support
>>>>>>> for
>>>>>>> my flash (Spansion S25FL512S NOR flash with SPI) or I have
>>>>>>> not
>>>>>>> proper
>>>>>>> configured SPI in U-Boot?
>>>>>>
>>>>>> I believe there is a problem with caches , which we still
>>>>>> didn't
>>>>>> identify. CCing Dinh and Chin, as they were the last ones
>>>>>> looking
>>>>>> into this problem.
>>>>>>
>>>>>> For now, try doing "dcache off" before using the QSPI NOR.
>>>>>>
>>>>>
>>>>> We managed to get it work for socfpga. One of the issue dragged
>>>>> me
>>>>> long
>>>>> is the CONFIG_SPI_FLASH_USE_4K_SECTORS. Need to ensure its not
>>>>> defined
>>>>> in the defconfig. Hope it helps
>>>>
>>>> This is not clear to me. You mean you were able to reproduce and
>>>> solve this cache (S-bit) related issue by disabling
>>>> CONFIG_SPI_FLASH_USE_4K_SECTORS? This option is disabled for all
>>>> SoCFPGA board in mainline.
>>>>
>>>> Could you please explain in more details what exactly you did to
>>>> solve this issue on SPI NOR?
>>>>
>>>
>>> Nope, I am not replicating the issue. My board is having Micron
>>> instead
>>> of Spansion flash. In previously, CONFIG_SPI_FLASH_USE_4K_SECTORS
>>> is
>>> defined in socfpga as most serial NOR flash are supporting 4k sub
>>> sector. With that, it would be good to ensure the 4K is undefined.
>>>
>>> In this case, wonder any details on the failure? Intermittent?
>>
>> I think we are talking about different things here. I'm referring
>> to Marek mentioning the cache problem (S-bit related) on current
>> SoCFPGA U-Boot mainline. With caches enabled you can experience
>> problems on QSPI and on USB (reported from Marek - I didn't test
>> USB yet).
>>
> 
> For QSPI, wonder the issue is on the read or write?

I'm not 100% sure here if this never happens on read. But it definitely
happens on write. saveeenv to SPI NOR causes serious problems here
for example.
 
>> So do you have any updated on this cache / S-bit problem?
> 
> I am still debugging this as I notice the hub is not able to detect the
> mass storage. This is only for certain pen drive.
> 
>> Or can you
>> use QSPI NOR without any issues on current mainline U-Boot with
>> caches enabled on your platforms?
>>
> 
> The issue I have is on USB only. For NOR, I can ubifsmount and
> ubifsload with Micron NOR flash without issue. This is with dcache
> enabled

Strange. I have Micron here on the SR1500 as well:

=> sf probe     
SF: Detected N25Q128 with page size 256 Bytes, erase size 64 KiB, total 16 MiB

Thanks,
Stefan