[PATCH v2 00/11] AT91, at91sam9x5ek updates (part II/III)

[Sam Ravnborg]

Hi Andrey.

While trying to port my proprietary at91sam9263 based board
I have stumbled over how the early init works.
And so far I have used at91sam9x5ek as reference.

If I follow the code paths for sam9x5 it looks like this:

	barebox_arm_head  (arch/arm/include/asm/barebox-arm-head.h)
	    _barebox_arm_head
	    b barebox_arm_reset_vector -->

	barebox_arm_reset_vector (arch/arm/mach-at91/at91sam9x5_lowlevel_init.c)
	    arm_cpu_lowlevel_init
	    arm_setup_stack(AT91SAM9X5_SRAM_BASE + AT91SAM9X5_SRAM_SIZE - 16);
	    barebox_arm_entry -->

	barebox_arm_entry (arch/arm/cpu/entry.c)
	    arm_setup_stack(arm_mem_stack_top(membase, membase + memsize) - 16);
	    arm_early_mmu_cache_invalidate
	    barebox_{multi,single,non}_pbl_start

	And then we have:
	ENTRY_FUNCTION(start_at91sam9x5ek, r0, r1, r2)  (arch/arm/boards/at91sam9x5ek/lowlevel.c)
	    arm_cpu_lowlevel_init
	    arm_setup_stack(AT91SAM9X5_SRAM_BASE + AT91SAM9X5_SRAM_SIZE - 16);
	    barebox_arm_entry


And something in this confuses me...
I know at91sam9x5 is built for multi image support.
Which is why start_at91sam9x5ek() is referenced in images/Makefile.at91

But why do we need to call arm_setup_stack() in three different places.
And with different parameters.
And arm_cpu_lowlevel_init is called from two places.

Can someone shed some light on this.

Thanks in advance,

	Sam