[U-Boot] Standalone application on secondary cores

[James Chargin <jimccrown@gmail.com>]

Dear Francesco Teodoro.

On 05/30/2014 01:35 PM, Francesco Teodoro wrote:
> I'm using a SABRE SD board (from Freescale) based on i.MX6 and the u-boot version is the 2014.04 one. What I've been trying to do is to activate the secondary cores so that I would be able to use them. First of all I've imported the commands cpu status/release/reset, then I checked if they were working in this way:
> U-boot > cpu 1 status (which gives as result: core1 disabled ...)
> U-boot > cpu 1 release 0x12000000 0
> U-boot > cpu 1 status (which gives as result: core1 enabled ...)
>
> Next step was to run a standalone application on secondary cores. First I checked the hello_world application, but it seems that the serial debug for secondary cores is not set (but I'm not sure). So I wrote an application to check if I could get changes in memory. This is the simple application (I just modified the hello_world one):
>

Please refer to 
http://www.denx.de/wiki/view/DULG/UBootStandalone#Section_5.12.4.

One of the first things done by the example stand alone application is 
to attempt to call back into U-Boot. This will not work correctly for 
cores other than 0.

Regards,
Jim Chargin