Sebastian Huber sebastian.huber at
Tue Jun 23 18:54:14 UTC 2015

See Doxygen comments of Per_CPU_State. The boot_card() must be called by exactly one processor.  For the Cortex-A9 MPCore there is a branch in bsp_start_hook_0() according to the CPU index.

----- Rohini Kulkarni <krohini1593 at> schrieb:
>Hi all,

I am trying to understand boot up for ARM BSPs so as to be able to implement SMP support for Pi 2.

Please correct me where I am wrong. (It is verbose. But I have tried to make things as clear as I could)

[1] From start.S for ARM, all cores start together. They run the bsp_start hook 0 and 1 and then go to boot_card() .
boot_card() calls rtems_data_sructure_initialize() which further does SMP related initilazations.

[2] the bsp_start_hooks include cpu initialization for cache/mmu etc. This is done for all cores before SMP initializations from boot_card(). For 
> Raspberry Pi 2, only primary core, which is core 0, will run after 
> reset, while other cores will wait for a jump address from where to 
> execute.
I need to ensure the sequence remains consistent for Pi 2. So before boot_card is called() , I need to get other cores to do the initialization from start.S while core0 waits. Is there something else that can be done?

[3] Where do the other cores start waiting for an interrupt from primary core. Where does the interprocessor interrupt come into picture.

Rohini Kulkarni

Sebastian Huber, embedded brains GmbH

Address : Dornierstr. 4, D-82178 Puchheim, Germany
Phone   : +49 89 189 47 41-16
Fax     : +49 89 189 47 41-09
E-Mail  : sebastian.huber at
PGP     : Public key available on request.

Diese Nachricht ist keine geschäftliche Mitteilung im Sinne des EHUG.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <>

More information about the devel mailing list