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Date: Mon, 21 Jan 2013 09:57:14 +0100
From: Matthieu CASTET <matthieu.castet@parrot.com>
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To: Huang Shijie <b32955@freescale.com>
Subject: Re: question: Why the nand_wait() wait for 20ms for nand program.
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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 ?