RE: [ECOS] [PATCH] AEB-1C memory SFR settings...

["Perry Wang" <perrywang at nmnc dot com>]

Hi,

I'm a newbie in embedded programming and eCos/AEB.  Excuse me if my comments
are ignorant.  I like to throw in some discussion.

This is from my hal_platform_setup.h

        .long   0xFFFFA008,0x00008000,0x00028000,0x00007804  /* segment 2 */
;\

It seems to be only using 128KB of SRAM.

I don't see the code handling different AEB revisions.  There's just one
config.  I'm using the latest eCos release from the web.  Should I be
getting latest devel tree from CVS?

Also, I believe the linker script would have to be changed if one wishes to
use more than 128KB or SRAM.  Mine shows:

MEMORY
{
    ram : ORIGIN = 0xc000, LENGTH = 0x1c000
}

This is only using 128KB

Maybe this is all being handled in the newest code in CVS.


QUESTION:

how do I properly map an additional memory device (in my case some FPGA
registers) to another segment at startup, without changing the original
hal_platform_setup.h.  Is it possible to do this in my ecos-work tree?


thanks!


> -----Original Message-----
> From: ecos-discuss-owner@sourceware.cygnus.com
> [mailto:ecos-discuss-owner@sourceware.cygnus.com]On Behalf Of Gary
> Thomas
> Sent: Friday, December 17, 1999 11:49 AM
> To: Srdjan Sobajic
> Cc: srdjans@digitalpersona.com; ecos-discuss@sourceware.cygnus.com
> Subject: RE: [ECOS] [PATCH] AEB-1C memory SFR settings...
>
>
>
> On 17-Dec-99 Srdjan Sobajic wrote:
> > Hi All,
> >
> > Maybe I missed some obvious way of doing this, but after checking out
> > the memory SFR settings on the AEB-1C I have, the board is configured
> > to use only 128 kB of the available RAM...
> >
> > So this patch fixes that problem right at startup, and makes the full
> > 256 kB RAM available.
> >
> > If there's a better way of doing this please let me know- but this works
> > for me.
> >
> > Srdjan
> >
> > (this is for $(BASEPATH)/packages/hal/arm/arch/current/src/vectors.S)
> >
> > --- vectors.S~        Wed Dec  1 13:33:38 1999
> > +++ vectors.S Wed Dec  8 14:50:26 1999
> > @@ -142,6 +142,18 @@
> >          // Come here to reset board
> >  warm_reset:
> >
> > +#ifndef CYGDBG_HAL_DEBUG_GDB_INCLUDE_STUBS
> > +     // Added to have 256 kB RAM available on AEB-1C with weird Flash
> > +     mvn r3, #24320
> > +     sub r3, r3, #243
> > +     mov r2, #294912
> > +     str r2, [r3] // set 0xFFFFA00C (Start3) to 0x48000
> > +     mvn r3, #24320
> > +     sub r3, r3, #215
> > +     mov r2, #294912
> > +     str r2, [r3] // set 0xFFFFA028 (Stop 2) to 0x48000
> > +#endif
> > +
> >  #if defined(CYG_HAL_STARTUP_RAM) && \
> >      !defined(CYGDBG_HAL_DEBUG_GDB_INCLUDE_STUBS)
> >       mrs     r7,cpsr                 // move back to IRQ mode
> >
>
> I don't understand why you think this is necessary.
>
> This setup is already being done in
> <cyg/hal/hal_platform_setup.h>, with code
> to handle the various AEB platforms.
>
> Did you configure your build for the AEB-1C?
> What does the comment "weird flash" mean above?