RE: [ECOS] Re: booting from ROM

[Gary Thomas <gthomas at redhat dot com>]

Note: this is the last time I'm going to respond without your email
being quoted on the list.  Queries sent directly to eCos engineers
that are not also copied to the ecos-discuss list will be ignored.

On Wed, 2001-10-17 at 20:59, Warren Jasper wrote:
> Gary,
> 
> Yes I did change CYG_HAL_STARTUP == ROM in ecos.ecc, and I have special
> linker scripts for
> rom startup.  An yes, I know that RedBoot works as a ROM startup
> application.
> 
> >You can't just take a RAM application and expect it to run from ROM.
> 
> What EXACTLY do you mean by that?  I thought changing CYG_HAL_STARTUP == ROM
> rebuilding ecos, recompiling the app and running objcopy -O binary and
> loading the
> binary image into FLASH and rebooting should be all I need to do.  Is there
> something
> else I'm missing?

No, that should be it.  The key is that you must rerun 'ecosconfig tree'
(or equivalent using the ConfigTool).  Just changing the 'ecos.ecc' file
is not sufficient, you must rebuild the tree.

Other than that it should work.  Certainly if you can build RedBoot for
a given platform and it runs from ROM, any other application will.

> 
> 
> -----Original Message-----
> From: Gary Thomas [mailto:gthomas@redhat.com]
> Sent: Tuesday, October 16, 2001 7:20 PM
> To: Warren Jasper
> Cc: 'Robert Lee'; ecos-discuss@sourceware.cygnus.com
> Subject: RE: [ECOS] Re: booting from ROM
> 
> 
> On Wed, 2001-10-17 at 01:59, Warren Jasper wrote:
> > I posted a similar question a few weeks ago.  I believe the problem is NOT
> > in the linker scripts.  When I tried to run the "hello world"
> > program from ROM (that worked correctly from RAM via gdb),
> > I could not get the UARTS to work correctly.  I even changed
> > printf to diag_printf, but that did not help.  I tried
> > just reading/writing to memory, and that works great, so
> > large parts of the startup is working correctly, only
> > the serial I/O is not. I have a custom board that is VERY
> > similar to the brutus/assabet ports.
> > 
> > If anybody has actually tested the "hello world" program
> > to run out of ROM, I sure would like to know what you configured in
> > the .ecc file and any other files to get it to work.
> > 
> 
> Ever hear of RedBoot? :-)  Honestly, this is just another eCos
> application (although it uses minimal eCos facilities), configured
> to execute from ROM.
> 
> >From the above description, it's not obvious that you've told eCos
> that this application should start from ROM.  You must set
>   CYG_HAL_STARTUP == ROM
> for this to work.  This changes the memory maps to coorespond with
> ROM applications, includes additional system startup code, etc.
> 
> You can't just take a RAM application and expect it to run from ROM.
> 
> > Warren
> > 
> > -----Original Message-----
> > From: Robert Lee [mailto:rlee_1900@yahoo.com]
> > Sent: Tuesday, October 16, 2001 12:47 PM
> > To: ecos-discuss@sourceware.cygnus.com
> > Subject: [ECOS] Re: booting from ROM
> > 
> > 
> > Hello,
> > 
> > I found the following message about running "hello
> > world" from ROM.  
> > 
> > Can anybody tell me what is MLT?  Where can I find
> > more information?  Why jflsh hello.bin to Assabet
> > doesn't work.  Thank you for your help.
> > 
> > 
> > > Tue, 09 Oct 2001 20:56:59 +0100 
> > > 
> > > You need to make new MLT files (.ldi and .h at
> > least) > for your ROM.
> > >
> > > Do a grep for CYG_HAL_STARTUP in the assabet and 
> > > brutus HALs to see what
> > > else is affected by the startup type.
> > >
> > > Jifl
> > 
> > =====
> > Robert Lee
> > Software Engineer
> > 
> > __________________________________________________
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