[Gumstix-users] Fwd: Sharing the GPMC Bus with other devices. e.g. FPGA

[James <ang...@gm...>]

Hi Philip,

I wonder if you have missing the below earlier message.

Would you be able to share more lights to this mysterious part of
communicating by GPMC on OMAP to/from FPGA?

Many thanks in adv.

James.

---------- Forwarded message ----------
From: JamesAng <ang...@gm...>
Date: Mon, Oct 24, 2011 at 12:15 PM
Subject: Re: [Gumstix-users] Sharing the GPMC Bus with other devices. e.g. FPGA
To: gum...@li...



Hi Philip,


Philip Balister wrote:
>
> On 10/02/2011 10:16 PM, JamesAng wrote:
>>
>> Hi Philip,
>>
>>
>> Philip Balister wrote:
>>>
>>> On 09/28/2011 03:14 AM, JamesAng wrote:
>>>>
>>>> Hi all,
>>>>
>>>> I know there are past discussions on the use of GPMC with FPGA but the
>>>> Nabble's search-engine is getting erratic results.
>>>>
>>>> Does anyone have a simple tutorial or documented guide on the use of a
>>>> simple GPMC driver&   user-land application to communicate (read/write)
>>>> to
>>>> FPGA using Overo? i.e. assuming the FPGA is another memory-storage like
>>>> the
>>>> NAND.
>>>>
>>>> I want to know if the GPMC resource can be shared for both Ethernet/LAN
>>>> and
>>>> other devices.
>>>
>>> Yes, it shares fine.
>>>
>>> This is probably more complex than you want :)
>>>
>>> https://github.com/balister/linux-omap-philip/commits/e100-2.6.38-2
>>>
>>> Philip
>>>
>>
>> Thanks in adv for pointing me to your share on the topic.
>>
>> Do you have some guides/wiki/documentations for newbies like me to start
>> reading from on using the GPMC with simple read/write to FPGA?
>>
>
> No :)
>
>> In that git repo, where should I start looking at to understand the
>> relevant
>> parts of the code used?
>
>
> arch/arm/mach-omap2/board-overo.c has the gpmc configuration code.
> drivers/misc/usrp_e.c has the actual driver code.
>

I'm reading the files and would if you have some documentation such as the
timing diagram, the data-flow, diagrams etc that I can use to x-reference to
the codes to understand it in detail?

Is there a user-land test application that is using the driver?

Many thanks in adv.

James.

-- 
Regards,
James