Re: [ECOS] about porting ecos in S3C4510B development board

[Jonathan Larmour <jifl at eCosCentric dot com>]

Hu, Ying wrote:
> Hi,
>  
>     Actually I don't have a good understanding about those memory 
> SECTIONs stated in the *.ldi files.
> what are the exact meaning for  SECTION_rom_vectors,  SECTION_text,  
> SECTION_fini,  SECTION_rodata, etc.?
>  
> Where can I find the detailed information about those SECTIONs?

These correspond to linker script sections. To get a foundation 
understanding you'll want to read up about how linker scripts work in 
embedded systems.

But you can also probably work out what's meant to happen by comparison 
with other working targets. In particular as Gary said:

>      > SECTIONS
>      > {
>      >     SECTIONS_BEGIN
>      >     SECTION_rom_vectors (rom, 0x2800000, LMA_EQ_VMA)
>      >     SECTION_text (rom, ALIGN (0x1), LMA_EQ_VMA)
>      >     SECTION_fini (rom, ALIGN (0x4), LMA_EQ_VMA)
>      >     SECTION_rodata (rom, ALIGN (0x4), LMA_EQ_VMA)
>      >     SECTION_rodata1 (rom, ALIGN (0x4), LMA_EQ_VMA)
>      >     SECTION_fixup (rom, ALIGN (0x4), LMA_EQ_VMA)
>      >     SECTION_gcc_except_table (rom, ALIGN (0x4), LMA_EQ_VMA)
>      >     SECTION_fixed_vectors (ram, 0x20, LMA_EQ_VMA)
>      >     SECTION_data (ram, 0x30000, FOLLOWING (.gcc_except_table))

The above line should probably have a figure more like 0x1000 than 0x30000. 
Otherwise it directly conflicts with the RAM usage of a loaded application 
of RAM startup type as seen in your quoted ram.ldi file.

You can fine tune the figures later when you know what the real RAM usage 
of RedBoot etc. in your final system is. A 0x30000 gap is probably 
overkill, but this should get things working at least.

Jifl
--
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