On Tue, Jun 14, 2011 at 9:49 AM, Nick Bane <nickbane1@gmail.com> wrote:
>> On Tue, Jun 14, 2011 at 9:12 AM, David Bisset
>> <david_bisset@btconnect.com>  wrote:
>>>
>>> I feel sure I must be missing the point given the complexity of the
>>> discussion to date.
>>> But my approach would be to punt the MMU page out of the way since it
>>> maps 0 into RAM from early in the Bootloader process.
>>> Then just talk directly to the NOR chip. There are a number of code
>>> blocks out there you could copy the NOR writing code from.
>>> Why try and make it a real NOR partition when it isn't formatted as a FS,
>>> its just a fixed sequence of blocks in a memory device holding a fixed
>>> sequence of binary data.
>>
>> I hadn't thought of that...I just started down the mtd path and never
>> thought to look left or right.
>>
> That was why I was suggesting a kernel firmware loader specific to the fpga.
> The trick here is how to stop and start NAND access while the fpga is being
> reprogrammed.

For my purposes, I don't need to reprogram the FPGA without requiring
a reboot.  I just wanted to be able to reprogram the image from
Linux-land rather than bootldr-land.  So all I need to do is to expose
the NOR flash for writing from userspace while running Linux.  Being
of a somewhat paranoid nature, I'd rather only expose the FPGA
partition of the NOR flash.

Wanting to contribute back to the community. I would like to do this
in such a manner as to allow others to build on it.  But I'm getting
pretty close to the "Hmmm, it works well enough for me to move on"
stage of development that I might just declare victory and move on.

But I'd really rather do something that contributes back.

--wpd