[En-Nut-Discussion] Nut/OS Initialization

[Harald Kipp]

Hi Ole,

Ole Reinhardt wrote:
> 
> For example in linux this is done by filling up a struct like this one
> 
> MACHINE_START(TRIZEPS4, "Keith und Koep Trizeps IV module")
>         /* MAINTAINER("Jürgen Schindele") */
>         .phys_io        = 0x40000000,
>         .io_pg_offst    = (io_p2v(0x40000000) >> 18) & 0xfffc,
>         .boot_params    = TRIZEPS4_SDRAM_BASE + 0x100,
>         .init_machine   = trizeps4_init,
>         .map_io         = trizeps4_map_io,
>         .init_irq       = pxa_init_irq,
>         .timer          = &pxa_timer,
> MACHINE_END
> 
> and linking it with the application. Right now I don't know the _exact_
> mechanism, but I should not be that complicate.

I understand the data structure and how it forces the linker to include 
the driver. But I do not understand, how the program code becomes aware 
of this structure to make use of the specified routines. In other words: 
How does the initialization code know that TRIZEPS4 exists and that it 
can call trizeps4_init() via (*init_machine)()?

Btw. not all compilers fully support C99, specifically designated 
structure initializers. But that's no big deal, just a bit more text to 
write.

Harald