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Date: Mon, 18 Mar 2013 17:13:13 +0100
From: Matthieu CASTET <matthieu.castet@parrot.com>
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To: Marek Vasut <marex@denx.de>
Subject: Re: [PATCH 1/3] mtd: m25p80: utilize dedicated 4-byte addressing
 commands
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Marek Vasut a écrit :
> Dear Matthieu CASTET,
> 
>> What's funny is the other side work :
>>
>> you can have a ROM that use 4-byte mode with 3-byte or 2-byte device as
>> soon as the read command is the same. [1]
> 
> Well, all of these are crap design. The SPI flash shall be power-cycled if the 
> platform reboots no matter what exactly to prevent having it in undefined state.
> 
This side (ROM that use 4-byte mode with 3-byte or 2-byte device) is used to
avoid detection of the flash by the rom (no need to know if spi eeprom or spi nor).