(toppers-users 4448) Re: FMP Programming Model

[Daniel Sangorrin]

Hi Pieter,

It's a bit hard to answer with so little information.
You should start by isolating the problem. For example:

- Does the problem exist when running FMP alone, or only when FMP runs on SafeG?
- What type of exception is it?
- Which part of the code is generating the exception?
- Are your functions using some instructions not supported by your
processor (in case of
  an undefined instruction exception) ?
- Do they require some coprocessor (VFP, SIMD) that is not supported
by the SoC or by FMP itself?

Regards,
Daniel







On Sat, Nov 7, 2015 at 1:32 AM, Pieter Maene
<pieter.maene ＠ esat.kuleuven.be> wrote:
> Hi,
>
> We are currently building a TrustZone application for a course at the
> University of Leuven. We use SafeG, with FMP in the secure world and Linux
> as the untrusted OS. A signature module is running in the trusted world and
> can be invoked to sign a message sent by the untrusted OS. The communication
> between the OSs works perfectly, but when a complicated function is invoked
> (e.g. the signing operation or deriving the public/private keypair), the CPU
> crashes with an "unregistered exception".
>
> I think I am missing a key concept of programming for FMP, or maybe
> misconfigured a setting for the kernel.
> Do you have an idea of what might be going wrong?
>
> Thanks in advance!
>
> Kind regards,
>
> Pieter Maene