FPGA registers userspace interface?

[lavi.kfir@gmail.com (Kfir Lavi)]

On Mon, Jan 3, 2011 at 5:09 PM, Kfir Lavi <lavi.kfir@gmail.com> wrote:

>
>
> On Mon, Jan 3, 2011 at 3:00 PM, Philip Downer <phil@pjd.me.uk> wrote:
>
>> On 03/01/11 12:47, Kfir Lavi wrote:
>>
>>  I have a FPGA that is constantly changing (its on development phase).
>>> I want to let userspace app to update those registers, but don't want to
>>> create an API yet.
>>> What is the best way to open a range of registers to userspace, so no
>>> driver update is required?
>>>
>>
>> When I had to do this recently I used sysfs, I have no idea if it's the
>> best way but it certainly was very effective. Remember in sysfs that each
>> file should only have one value.
>>
>> Once it's setup though you can just write to the sysfs files, I started by
>> writing simple perl scripts to test things before starting to write more
>> complex apps.
>>
>> HTH
>>
>> Phil
>>
> So what do expose in sysfs? for each register - a file of it's own? or you
> get a bulk of data to one file?
>
> Thanks,
> Kfir
>

I thought about using 3 files in sysfs.
1. address of the register
2. data to write to the register
3. trigger that do the write

Please share your comments.
Regards,
Kfir
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.kernelnewbies.org/pipermail/kernelnewbies/attachments/20110103/d9f16f74/attachment.html