Re: NAND review

[Simon Kallweit <simon.kallweit@intefo.ch>]

Andrew Lunn wrote:
>> The philosophical question for us all is whether NAND on its own should be
>> allowed to use malloc, given that a NAND array will probably always be used
>> in conjunction with a log-structured filesystem which will chew up
>> comparatively large amounts of RAM (and, of course, RAM is forever getting
>> cheaper). Is this a corner or even N-dimensional vertex case; will it
>> necessarily always be the case that a device with NAND flash will have
>> enough RAM to support it? Do boards with NAND but not much RAM exist, and if
>> so do we care about them?
> 
> The answer is yes. Simon, could you describe your board. From what i
> understand you don't have much RAM. 

Well yes, our current hardware has 512k on-chip flash, 64k on-chip ram 
and 128k external ram. For additional storage we currently have a 4mb 
NOR flash, but we're planning on replacing this with a NAND flash so we 
can run a tiny filesystem like UFFS. The current software does only use 
static memory with the exception of lwIP, which uses fixed memory pools 
for dynamic allocation.

For upcoming products we were thinking about getting rid of the external 
ram, which would leave us with only 64k. But this certainly would lead 
to problems in other areas as well.

Simon