x86_64 support?

[Jan Sommer]

Am 2017-02-09 22:07, schrieb Chris Johns:
> On 10/02/2017 02:22, Joel Sherrill wrote:
>> On Feb 9, 2017 7:29 AM, "Jan Sommer" <soja-lists at aries.uberspace.de
>> <mailto:soja-lists at aries.uberspace.de>> wrote:
>> 
>>     Hello,
>> 
>>     As far as I see there is no support for x86_64 yet. I found that
>>     there was a GSoC proposal to add BSP for the architecture, but I 
>> am
>>     not sure if it was accepted.
>> 
>>     Does someone know what is the current status of 64bit support and
>>     what would be missing for a working BSP with a PCI and clock 
>> driver?
>> 
[...]
> 
> I recently updated the x86_64 project ticket and I suggest checking it 
> ...
> 
>  https://devel.rtems.org/ticket/2898
> 

Thank you for all the information. I am not sure that we have the 
experience for such a project available atm.
I am not that familiar with the details of x86, but would it be possible 
to run a i386-BSP-application on a 64bit-CPU (e.g. something like 
http://www.systerra.de/documents/IDAN-CMA24GS_DS1.pdf)?
Given that we don't need any 64bit features, is it much work to start an 
RTEMS application in the 32bit compatibility mode?


Best regards

    Jan

> The project and tasks are listed in the ticket. An important issue is
> support for Intel's ACPICA code. Handling all the tables a modern BIOS
> creates is lots of work without the Intel code. I think FreeBSD's
> version is a good start. The same goes for UEFI run-time support.
> 
> We also need to examine the effect the change has on any hyper-visors
> or partitioning wrappers that support RTEMS. I would like to see the
> 32bit i386 BSP removed from the source tree.
> 
> Chris