[PATCH 04/10] bus: introduce an Marvell EBU MBus driver

Jason Gunthorpe jgunthorpe at obsidianresearch.com
Fri Mar 8 13:31:20 EST 2013


On Fri, Mar 08, 2013 at 02:59:27PM -0300, Ezequiel Garcia wrote:

> > I looked through Ezequiel's patch and saw a driver that provided those
> > properties and no user of them at all. Are the patches incomplete? Is
> > there some plan to use these values in the future?

> Leaving aside the review comments that still I haven't addressed yet,
> the patchset is complete.
 
> The timings parameters were not set in device tree files,
> not because I expected the bootloader to set them, but instead because
> SoC default values worked fine for the NOR devices I tested.

? Isn't that the same thing? Were the timing registers the SOC reset
default or were they leftover from the bootloader?

> If this is suboptimal, I can fix the device tree files in v2
> to set proper timings parameter values.

I have no opinion on this for your boards, it depends entirely on what
flash chips you have to be compatible with, and how you feel about
your bootloader.

Also, when looking at the idea from Maxime it occured to me that your
DT binding might be better using ns or ps for the timings, instead of
tclk cycles? That way NAND/NOR datasheet values can be included in the
DT directly and are correct no matter what the tclk frequency is set to.

Cheers,
Jason



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