Re: [Qemu-devel] [PATCH v2 7/9] i.MX: Add i.MX6 SOC implementation.

[Jean-Christophe DUBOIS <jcd@tribudubois.net>]

Le 29/02/2016 22:14, Peter Maydell a écrit :
> On 29 February 2016 at 20:34, Jean-Christophe DUBOIS
> <jcd@tribudubois.net> wrote:
>> Le 29/02/2016 18:58, Peter Maydell a écrit :
>>> To answer the question of "which of these is the correct thing to do"
>>> we need to look at what the real hardware does when it's running Linux:
>>> does it run Linux in Secure or Nonsecure?
>>
>> i.MX6 is definitively able to boot in secure/trustzone mode (there are some
>> demo out there about it) so I guess it might be booting in secure mode.
>
> Mmm. The other question I had about the system reset controller
> is whether it's really purely hardware doing the "start secondary CPU",
> or is it just a funny way of asking the system firmware to start
> things, or is the stuff like the register for startup address
> just a place to leave information that the system firmware
> on the secondary CPU will read as part of its boot sequence?
>
> Is there a datasheet available for this?

Well the SRC device is described in the i.MX6 reference manual.

http://cache.nxp.com/files/32bit/doc/ref_manual/IMX6DQRM.pdf?fpsp=1&WT_TYPE=Reference%20Manuals&WT_VENDOR=FREESCALE&WT_FILE_FORMAT=pdf&WT_ASSET=Documentation&fileExt=.pdf

I believe it is hardware based. Now it might involve some of the 
functions of the internal ROM in the process but we cannot change this 
behavior in any way.

>
> thanks
> -- PMM
>