question: Why the nand_wait() wait for 20ms for nand program.
Matthieu CASTET
matthieu.castet at parrot.com
Mon Jan 21 03:57:14 EST 2013
Huang Shijie a écrit :
> 于 2013年01月18日 20:26, Matthieu CASTET 写道:
>> Huang Shijie a écrit :
>>> Hi all:
>>> Why the nand_wait() wait for 20ms for nand program. could we
>>> expand this time to 40ms? I have a nand chip : Micron MT29F64G08CBABAWP.
>>> The chip's BUSY/READY pin may needs more then 20ms to become ready,
>>> though its
>>> datasheet tells me the tPROG's max value is 2.5ms.
>>>
>> Don't you have an hardware problem (missing pullup/down on ready busy pin) ?
>>
>> If the datasheet say the max value is 2.5 ms , how it can be more than 20 ms.
>
> I finally found the root cause.
>
> I added the do_gettimeofday() in the nand_wait() to measure the
> READY/BUSY time. The code is like this:
> ---------------------------------------------------- code start
>
Could you dump jiffies and timeo in your code ?
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