Re: [ECOS] Insight 5.1.1 with Angel /serial debugger

[Jonathan Larmour <jlarmour@redhat.com>]

Jing Luo wrote:
> 
> Hi,
> Thanks Jesper. Now I know porting eCos is not that easy.

Porting eCos to work with proprietary ROM monitors may not be as easy, no.

> I choose the second option you suggested - port Redboot.
> 
> I changed the hal-platform-setup.h for hardware initialization.
> 
> I want to start Redboot from RAM, but the problem is the memory layout came
> out is not the way I wanted as the following.
> [mlt_arm_mytarget_ram.ldi]
> // eCos memory layout - Thu Feb 28 18:55:04 2002
> 
> // This is a generated file - do not edit
> 
> #include <cyg/infra/cyg_type.inc>
> 
> MEMORY
> {
>     ram : ORIGIN = 0xc0000000, LENGTH = 0x2000000
> }
> 
> SECTIONS
> {
>     SECTIONS_BEGIN
>     SECTION_fixed_vectors (ram, 0xc0000000, LMA_EQ_VMA)
>     SECTION_rom_vectors (ram, 0xc0020000, LMA_EQ_VMA)
>     SECTION_text (ram, ALIGN (0x4), LMA_EQ_VMA)
>     SECTION_fini (ram, ALIGN (0x4), LMA_EQ_VMA)
>     SECTION_rodata (ram, ALIGN (0x4), LMA_EQ_VMA)
>     SECTION_rodata1 (ram, ALIGN (0x4), LMA_EQ_VMA)
>     SECTION_fixup (ram, ALIGN (0x4), LMA_EQ_VMA)
>     SECTION_gcc_except_table (ram, ALIGN (0x4), LMA_EQ_VMA)
>     SECTION_data (ram, ALIGN (0x4), LMA_EQ_VMA)
>     SECTION_bss (ram, ALIGN (0x4), LMA_EQ_VMA)
>     CYG_LABEL_DEFN(__heap1) = ALIGN (0x8);
>     SECTIONS_END
> }
> 
> After build library and look in the map, __exception_handlers start from
> address 0x20000 which is in the ROM.
> I am confused about that. How can I make it run from RAM?

Compare with other ports and look at their .ldi files. For example, you'll
see that fixed_vectors should be at 0x20 generally.

> Have anyone had experience to run Redboot from RAM?
> 
> Another question about the linker file:
> what LMA_EQ_VMA mean?

Load address is the same as the address the program is expected to run at.
This is correct for RAM startup.

Jifl
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