Forums

porting linux to arm

Started by renjith_rohin April 22, 2011
Dear all,
I am new on porting linux to arm.i want to port the linux kernel to ARM platform ,but i don't know how to begin.I am having an embedded kit in which ARM7TDMI-S(philips LPC 2362) is the core.But I think i am having only 128 kB on-chip flash and 32KB SRAM on LPC2362.Is it enough for porting linux.If no which controller I should take for starting my project??
Please give your valid suggestions.
Thank you all.

An Engineer's Guide to the LPC2100 Series

On 22/4/2011 7:34 AM, renjith_rohin wrote:
> Dear all,
> I am new on porting linux to arm.i want to port the linux kernel to ARM
> platform ,but i don't know how to begin.I am having an embedded kit in
> which ARM7TDMI-S(philips LPC 2362) is the core.But I think i am having
> only 128 kB on-chip flash and 32KB SRAM on LPC2362.Is it enough

128k flash / 32k RAM won't do for Linux. Think more like 64M RAM. Flash
is less of an issue because you can use USB stick or SD card. You won't
find this amount of memory on a single-chip uC. Better look at a
board-level solution. I love my FriendlyARM SDK board:
http://www.friendlyarm.net/products/micro2440 I payed E 120 for a
Linux/Android/WinCE board with graphic+touchschreen. ~ E 60 for a
serial-line only board.

--

Wouter van Ooijen

-- -------
Van Ooijen Technische Informatica: www.voti.nl
consultancy, development, PICmicro products
docent Hogeschool van Utrecht: www.voti.nl/hvu

--- In l..., Wouter van Ooijen wrote:
>
> On 22/4/2011 7:34 AM, renjith_rohin wrote:
> > Dear all,
> > I am new on porting linux to arm.i want to port the linux kernel to ARM
> > platform ,but i don't know how to begin.I am having an embedded kit in
> > which ARM7TDMI-S(philips LPC 2362) is the core.But I think i am having
> > only 128 kB on-chip flash and 32KB SRAM on LPC2362.Is it enough
>

You will probably want to move to an ARM9 chip as the ARM7s don't have the memory management unit (MMU). If you don't want to go that far, you MIGHT be able to port uClinux (a derivative of Linux) as it doesn't require an MMU.

The Hammer is a pretty small platform that supports full Linux:
http://tincantools.com/

The gumstix is another:
http://gumstix.com/

Sparkfun has boards like:
http://www.sparkfun.com/products/9047

Here is an app note on porting uClinux to the LPC22xx series of ARM7 devices:
http://ics.nxp.com/support/documents/microcontrollers/pdf/an10389.pdf

The Blackfin BF537 Stamp is a very fast 16 bit uClinux board:
https://docs.blackfin.uclinux.org/doku.php?id=hw:boards:bf537-stamp

Google for 'ARM9 Linux' for more

Richard

On Friday 22 April 2011 16:46:47 Wouter van Ooijen wrote:

> On 22/4/2011 7:34 AM, renjith_rohin wrote:
> > Dear all,
> > I am new on porting linux to arm.i want to port the linux kernel
> > to ARM platform ,but i don't know how to begin.I am having an
> > embedded kit in which ARM7TDMI-S(philips LPC 2362) is the
> > core.But I think i am having only 128 kB on-chip flash and 32KB
> > SRAM on LPC2362.Is it enough
>
> 128k flash / 32k RAM won't do for Linux. Think more like 64M RAM.

4Mb flash and 2mb ram with xip uClinux.

> Flash is less of an issue because you can use USB stick or SD card.
> You won't find this amount of memory on a single-chip uC. Better
> look at a board-level solution. I love my FriendlyARM SDK board:
> http://www.friendlyarm.net/products/micro2440 I payed E 120 for a
> Linux/Android/WinCE board with graphic+touchschreen. ~ E 60 for a
> serial-line only board.
--
Rgds
JTD
--- In l..., jtd wrote:
>
> On Friday 22 April 2011 16:46:47 Wouter van Ooijen wrote:
>
> > On 22/4/2011 7:34 AM, renjith_rohin wrote:
> > > Dear all,
> > > I am new on porting linux to arm.i want to port the linux kernel
> > > to ARM platform ,but i don't know how to begin.I am having an
> > > embedded kit in which ARM7TDMI-S(philips LPC 2362) is the
> > > core.But I think i am having only 128 kB on-chip flash and 32KB
> > > SRAM on LPC2362.Is it enough
> >
> > 128k flash / 32k RAM won't do for Linux. Think more like 64M RAM.
>
> 4Mb flash and 2mb ram with xip uClinux.
>
> > Flash is less of an issue because you can use USB stick or SD card.
> > You won't find this amount of memory on a single-chip uC. Better
> > look at a board-level solution. I love my FriendlyARM SDK board:
> > http://www.friendlyarm.net/products/micro2440 I payed E 120 for a
> > Linux/Android/WinCE board with graphic+touchschreen. ~ E 60 for a
> > serial-line only board.
> --
> Rgds
> JTD
>

You should start at www.LPCLinux.com for Linux or uCLinux. You can also check out Rowebots for a small Linux port.
http://www.rowebots.com/embedded_processors_supported/arm_cortex_m3_nxp_1700

Gene

Can I use the SDCard or a USB Flash drive as a virtual RAM?
At first I googled it and I think it is possible with PCs now.
Waiting for the valid suggestions.
try

l...

regards

Jean-Jacques
--- In l..., renjith ks wrote:
>
> Can I use the SDCard or a USB Flash drive as a virtual RAM?
> At first I googled it and I think it is possible with PCs now.
> Waiting for the valid suggestions.
>

--- In l..., renjith ks wrote:
>
> Can I use the SDCard or a USB Flash drive as a virtual RAM?
> At first I googled it and I think it is possible with PCs now.
> Waiting for the valid suggestions.
>

Of course it will work. My Win 7 machine uses a Compact Flash as a cache.

It might be better to use an ARM9 with the MMU (Memory Management Unit) to implement virtual memory. There are a lot of Linux ports running on ARM9s. There are also uCLinux implementations which don't require the MMU running on ARM7s.

http://www.uclinux.org/pub/uClinux/ports/arm7tdmi/

Creating a virtual memory system from scratch might be a lot of work. Older computers such as the IBM 1130 implemented it at a trivial level by having features such as LOCAL (Load On Call) and SOCAL (System Load On Call) where a fixed chunk of memory was set aside for transient code and there was a modest scheduler that loaded the area with subroutines retrieved from disk as they were called, This all ran well in a machine with as little as 4k words. It was up to the user to specify which routines would be overlayed.

Richard

--- In l..., "rtstofer" wrote:
>
> --- In l..., renjith ks wrote:
> >
> > Can I use the SDCard or a USB Flash drive as a virtual RAM?
> > At first I googled it and I think it is possible with PCs now.
> > Waiting for the valid suggestions.
> > Of course it will work. My Win 7 machine uses a Compact Flash as a cache.

Wow, it would seem to me that this would be slow to program and have a limited life !

Does this really work on a daily basis ?
What Win 7 machine are you using ?

Wouldn't real RAM be better for this type of thing ?
A Win 7 64-bit machine with lots of GBs of RAM would be far faster/cheaper and more reliable, right ?

don

On Thu, May 5, 2011 at 9:12 PM, renjith ks wrote:

> Can I use the SDCard or a USB Flash drive as a virtual RAM?
> At first I googled it and I think it is possible with PCs now.
> Waiting for the valid suggestions.
>

Any reason you can't set it up as disk swap?