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Date: Tue, 14 May 2013 17:43:14 +0530
From: Sourav Poddar <sourav.poddar@ti.com>
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Subject: Re: Qspi flash device  driver - framework to use?
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On Friday 10 May 2013 04:39 PM, Sourav Poddar wrote:
> Hi,
>
> I am trying to work out a way to write a QSPI serial flash interface 
> driver
> for my IP. The idea is to have an execute in place usecase.
>
> We have a configuration port from which the spi core can be configured 
> and a
> memory mapped port from which the data can be read/write from/to serial
> flash device.
>
> As far as I can understand, I dont think it will be correct/possible 
> to write this
> driver making use of the generice spi framework(drivers/spi/spi.c) as 
> that
> framework is more suited for generic spi use case, where in you can load
> your Image from external SPI devices into DDR and then execute. ?
>
> But for cases, where qspi is connected to serial flash device (XIP is 
> needed) what
> we might need is some framework which just passes the buffers and its 
> length to
> our driver which in turn will configure the qspi to initiate the 
> transfer.
>
> What can be the best framework to use for the above use case?
>
> I saw a device(m25p80) using mtd framework for some similar usecase.
> Is it the mtd which should be used? OR will it be a
> good idea to go for a generic qspi framework(drivers/qspi) which can be
> used by qspi flash devices having a memory mapped interface. ?
>
> Thanks,
> Sourav