Digi CCWMX53

[Russell Haley]

Ian,

Thanks for your candid response. I was waiting for this shoe to drop.
I would not say I am discouraged, I would say that my expectations
have been tempered. Let me evaluate what you have said and I will
consider my options.

Thanks,

Russ



On Tue, Oct 7, 2014 at 6:16 AM, Ian Lepore <ian at freebsd.org> wrote:
> On Mon, 2014-10-06 at 21:41 -0700, Russell Haley wrote:
>> Hey,
>>
>> Okay, I lied about waiting till the weekend. I am looking at the atmel
>> files. Should I be replacing the at91 moniker with imx (processor
>> class) or mx53 (implementation)?
>>
>> Thanks,
>>
>> Russ
>
> With a quick glance at the manuals, it appears imx51 and imx53 have the
> same nand controller hardware, but imx6 is completely different, so
> 'imx5' would be the right prefix for file and function/data names.
>
> That said, I want to point out that there's a huge difference between
> the simplistic memory controller for accessing nand in the at91 hardware
> and the much more complex nand hardware in the imx5 series.  I don't
> think you're going to get far by trying to copy the at91 driver.  In
> fact, I think you're going to find it impossible to make the imx5 BCH
> hardware work with the upper layers of the nand software in freebsd
> without some serious redesign of the upper layers (and then of course
> the associated rewriting of existing low-level nfc drivers).
>
> It's not that I want to discourage you from trying, I just want to be
> realistic here.  What you're embarking on isn't a couple days of
> converting an existing driver -- in my estimation, you're looking at
> weeks of work.  I don't mean 3 calendar weeks of a couple hours each
> evening hobbyist work, I'm talking hundreds of hours of development
> time.  The harsh reality is that freebsd doesn't have adequate nand
> flash support for modern hardware.  We don't even have the framework of
> a design that can accomodate things like hardware offload of ECC.
>
> -- Ian
>
>