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Date: Fri, 18 Oct 2013 11:31:14 +0100
From: Mark Brown <broonie@kernel.org>
To: Sourav Poddar <sourav.poddar@ti.com>
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Subject: Re: [PATCH 1/3] spi/qspi: Add memory mapped read support.
Cc: Peter Korsgaard <peter@korsgaard.com>, Trent Piepho <tpiepho@gmail.com>,
 "Balbi, Felipe" <balbi@ti.com>,
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On Fri, Oct 18, 2013 at 12:57:51PM +0530, Sourav Poddar wrote:

> 3. For filling memory mapped register in qspi controller, we can
> pass that information
>     from dt rather than hardcoding as macros.

Or from the flash driver at runtime...

>     4b.
>         Roadblock:
>         Runtime clock management is handle by SPI framework, so while
>         doing memory read, where we bypass SPI framework, clocks will be
>         disable and we will get an abort while doing memcpy.

>        Possible solution:
>            As suggested by Trent, we can keep the SPI controller
> clocks always ON ?

At the SPI layer I would keep the clocks on while the driver has a
region mapped for the flash layer.  The flash layer can then decide when
to keep the region mapped, for example it could do so whenever the
device is opened.

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