This is the mail archive of the
ecos-discuss@sourceware.org
mailing list for the eCos project.
RE: ROMRAM Application on xScale (PXA255)
- From: Mark Salter <msalter at redhat dot com>
- To: jporthouse at toptech dot com
- Cc: ecos-discuss-return-34516-jporthouse=toptech dot com at ecos dot sourceware dot org, "'eCos Discussion'" <ecos-discuss at ecos dot sourceware dot org>
- Date: Fri, 24 Mar 2006 15:53:49 -0500
- Subject: RE: [ECOS] ROMRAM Application on xScale (PXA255)
- References: <MDAEMON-F200603241344.AA4441140md50000000022@toptech.com>
On Fri, 2006-03-24 at 13:49 -0500, Joe Porthouse wrote:
> Mark/All,
>
> Thanks for the reply. I did not find any ROMRAM support in the
> IXDP425 (..._ixdp425_romram.ldi or other support files), but I did find some
> in the uE250 target platform.
Its in CVS...
> I believe I have found all the references I needed to update but I
> am still running into problems getting the application to run.
>
...
> With the ROMRAM startup type the "ldr r2,1f" loads r2 with
> 0x00000xxx, the RAM address to continue execution. Problem is that the
> image is not copied from flash to RAM until later in the startup. Execution
> is suppose to continue in flash at 0x50000000.
...and the ixdp425 port deals with this issue thusly:
// value to load into pc to jump to real runtime address
ldr r0, =1f
#if defined(CYG_HAL_STARTUP_ROMRAM)
// R0 holds a RAM address for ROMRAM startup,
// so convert to a flash address.
orr r0, r0, #IXDP_FLASH_BASE
#endif
--Mark
--
Before posting, please read the FAQ: http://ecos.sourceware.org/fom/ecos
and search the list archive: http://ecos.sourceware.org/ml/ecos-discuss