This is the mail archive of the
ecos-discuss@sources.redhat.com
mailing list for the eCos project.
ROMRAM start for ARM
- To: eCos Disuss <ecos-discuss at sourceware dot cygnus dot com>
- Subject: [ECOS] ROMRAM start for ARM
- From: Andrew Lunn <andrew dot lunn at ascom dot ch>
- Date: Tue, 5 Jun 2001 17:55:04 +0200
Hi Folks
Im trying to figure out how to make the ARM family ROMRAM start. In
particular im interested in the EBSA285.
I have to modify PLATFORM_SETUP1 so that after its setup the DRAM it
copies the image from ROM into RAM. My question is, what exactly do i
have to copy from where to where?
I need to copy the text, rodata sections. What about the rom_vectors
and fixed_vectors section? I assume these also need copying. It looks
like i just have to copy the image to address 0x0.
I assume a ROMRAM application is linked using the RAM memory layout?
So all symbols will have the RAM values. How do i get the address the
code is currently in ROM? Does the linker know this or do i just have
to hard code it? It looks like the MIPs has the FLASH address
hardcoded into it. Is there is symbol i can use the find out how much
i have to copy? __rom_data_end?
At the moment it looks like i need to do the equivelent of
memcpy(0,FLASH_START,__rom_data_end);
goto ram
ram: nop;
Does this seem right?
Thanks
Andrew