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Re: AW: eCos porting questions


>>>>> "Joerg" == =?iso-8859-1?B?SvZyZyBSYXBrYQ==?=  <iso-8859-1> writes:


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

You mean the contents of the HAL_SavedRegisters structure is
different? Doesn't matter, the stub treats them differently (due to
the architecture stub specific code).

The reason you want to call cyg_hal_exception_handler is that calling
into the debugger doesn't make sense for all configurations. And since
all architectures have the configury in the C function and not
somewhere in the assembly code, you should put it there as well.

But aside from that point (precedent), there's nothing preventing you
from calling the function from vectors.S.

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

From the gas info page:

`.section NAME'
===============
[AOUT data snipped]

   For ELF targets, the `.section' directive is used like this:
     .section NAME[, "FLAGS"[, @TYPE]]
   The optional FLAGS argument is a quoted string which may contain any
combintion of the following characters:
`a'
     section is allocatable

`w'
     section is writable

`x'
     section is executable



Jesper

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