This is the mail archive of the ecos-discuss@sources.redhat.com mailing list for the eCos project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Re: Run Time Loader (without RedBoot)


Hi Steve,
Thank you for your response, but I am not exacly in this case.
Actually, the Bios part will always be running, and the application will be running on top of that.
I can manage to have the bios copying the Application from the Flash to the RAM, at a fixed and previously known RAM address. But this limit my architecture to be splitted forever with a bios RAM zone and an application RAM zone, that can not have theire size/location changed in the future.
This is what I want to avoid, as the bios tends to get bigger and bigger, and overlap the application zone wich seems to be oversized (for now) for the application.
But my question was, more precisely, does a kind of run time loader exist under eCos, or does eCos provides facilities to handle position-independent code? It becomes clearer that it does not. I have to think about another solution.
Regards,
Guilly



From: Steve Strublic <SStrublic@Hypercom.com>
To: guilly_work@hotmail.com
Subject: Re: [ECOS] Run Time Loader (without RedBoot)
Date: Thu, 16 Jun 2005 08:57:53 -0700





Hi Guilly,

We did run into a very similar scenario, where we wanted the device to boot without Redboot, and
then be replaced by the application. What we did was create a minimal eCos 'loader' application (no
Ethernet, no serial support, with flash support) that pretty much only knew how to access flash. We
built our run-time application as a RAM image, located at address 0, and loaded the image from flash
to address 0. Once loaded, the application was started, and voila!


The loader was a reasonably small size (under 80k), and you could probably trim that down some. And
as you desire, the application was completely independent of the loader. All drivers were included
in the application, as the loader was no longer in existence when the app was running.


I don't think you'll have much luck with a position-independent image in eCos, but then again I've
never tried to actually build one.


HTH,

Steve

--------

"2 is not equal to 3 - not even for very large values of 2." -- Grabel's Law




guilly_work@hotmail.com
Sent by:
ecos-discuss-owner@ecos.sou To
rceware.org ecos-discuss@sources.redhat.com
cc


06/16/2005 07:10 AM Subject
[ECOS] Run Time Loader (without RedBoot)











Hi,
I'm moving from pSos to eCos. There was a very usefull feature in pSos that
I can't find in eCos, which is the run time loader.
In know that RedBoot can load images from flash to it's RAM location, but I
don't want to use RedBoot, and I need to load a relocatable image, i.e. a
location-independent image.
Actually, my system is composed of 2 parts :
- 1rst part, the "Bios", wich includes eCos and some drivers to the hardware
of our card
- 2nd part, the "Application", wich make use of the bios to access the
hardware features.
I want first to run the Bios, initialize my hardware, then load the
application in RAM to be executed.
But I would like to be able to load this application anywhere int the RAM,
where there is some place left actually, which is not know at link time of
the application. I want to keep the Application as much independent as
possible of the Bios version.
I'm sure somebody has already encoutered this problem, but I did not find
any post about it, and I run out of keyword to get some help through Google.
Thank you for your help
Guilly


_________________________________________________________________
Vidéoconférence plein écran avec MSN Messenger http://g.msn.fr/FR1001/866


-- Before posting, please read the FAQ: http://ecos.sourceware.org/fom/ecos and search the list archive: http://ecos.sourceware.org/ml/ecos-discuss




_________________________________________________________________
MSN Messenger : personnalisez votre messagerie instantanée ! http://g.msn.fr/FR1001/866



-- Before posting, please read the FAQ: http://ecos.sourceware.org/fom/ecos and search the list archive: http://ecos.sourceware.org/ml/ecos-discuss


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]