[V5 PATCH 1/1] driver:mtd:spi-nor: Add quad I/O support for Micron spi nor

bpqw bpqw at micron.com
Thu Nov 13 18:06:04 PST 2014


>> This maybe your spi controller is still extended mode, Once EVCR bit 7 
>> is set to 0, the spi nor device will operate in quad I/O.Command-address-data line is 4-x-4.
>> So after send WRITE EVCR command , spi controller also  must transfer 
>> to quad I/O Mode,and set its Command-address-data line also Should be 4-x-4 .

>Thanks, this helped.  I added some code to snoop the command stream for WRITE EVCR with quad mode, 
>and then set up the quad mode in the controller.  Seems kinda ugly, but working now.

>-Graham

Yes ,if enable spi nor Quad I/O, firstly, must check spi controller if support Quad I/O protocol,
and after enable spi nor Quad I/O mode ,spi controller also must be transferred to Quad I/O protocol.
Their two side must be matched together.
Maybe spi controller can do this changes.

Hi,Brian

Can you give me some tips about this patch? Thanks!

-Bean Huo



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