Re: [Qemu-devel] [ARM] Cortex-R4F and VFP3-D16

[Fabien Chouteau]

On 02/28/2013 03:16 PM, Peter Maydell wrote:
> On 28 February 2013 14:01, Fabien Chouteau <address@hidden> wrote:
>> On 02/27/2013 09:49 PM, Paul Brook wrote:
>>> I've got a patch to implement this as a side-effect of a different feature,
>>> I'll look at pushing it out.
>>
>> Great, don't hesitate to ask if you want some help.
>>
>> In the meantime I have another question for you. In
>> helper.c:vfp_gdb_get_reg(), there's a comment:
>>
>>  /* VFP data registers are always little-endian.  */
>>
>> and all the load and store are stfq_le_p and ldfq_le_p. I don't
>> understand why VFP registers should always be little-endian.
> 
> This is a question of how GDB defines these registers to be
> transmitted over the remote protocol -- you'd need to find
> the corresponding gdb docs/code.

I will ask to our GDB experts.

>> In fact I'm
>> working on a big-endian R4F (TMS570) and I have endianness issue in the
>> communication with GDB.
>
> If you're also trying to get big-endian mode to work (linux-user
> mode or system emulation?) you may have more problems than merely
> implementing R4 support or VFP-D16 :-)
>

I already built qemu-system-armeb, and implemented few devices of the
TMS570 (rti, sci, and vim). Besides this GDB issue I have no endianness
problem so far.

> Are you planning to do the v7 PMSA support?
>

I don't know what that is, but I'll take a look :)

Regards,

-- 
Fabien Chouteau