AW: [ECOS] eCos porting questions

[Jörg Rapka]

Dear Jesper,

Joerg> 2. For the GDB stub I have to implement an exception
Joerg> handling. In the document I read, that the entire processor
Joerg> state must be saved, interrupts must be disabled and then the
Joerg> debugger entry point must be invoked.  What are the entry point
Joerg> for the debugger? Is it function "void __handel_exception
Joerg> (void);" defined in file "/hal/common/generic-stub.c"?  If it
Joerg> is so, how did this function use the saved processor state
Joerg> (since this function has no input parameter)?  In the file
Joerg> "/hal/ARCH/include/hal_arch.h" the structure
Joerg> "HAL_SavedRegisters" is defined.  Did I need a variable of this
Joerg> type to handle the stuff above?

Jesper>Look in powerpc/arch/.../src/hal_misc.c - the true entry point is
Jesper>cyg_hal_exception_handler(HAL_SavedRegisters *regs) which sets the
Jesper>global variable _hal_registers - this is where the stubs get the
Jesper>registers from.

I have found the function "cyg_hal_exception_handler". But for the some 
architectures (e.g. mips, sparclite) the parameters are different. So
my question is: Do I have to use this function or can I also call
"__handle_exception" from an assembler implementation in file "vector.S"?

Another question to the memory regions defined by the linker. If I use
the following assembler statement:
.section ".vectors","ax"
The memory region '.vectors" will be created. I know about the .section
command in as, but the parameters above are different from description.
Can you give me a link to the current documentation.
Why use .vectors in quotation marks and what is the meaning for "ax"?

Thanks in advance for help.

Best regards
Joerg