Re: [Tee-dev] Persistent filesystem between reboots

Re: [Tee-dev] Persistent filesystem between reboots

[Jens Wiklander]

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Hi Kris,

On Thu, Jan 14, 2021 at 1:37 PM Kris Kwiatkowski <kris@amongbytes.com> wrote:
>
> Hi,
>
> I'm using HiKey 960 for my research project. I've noticed that
> filesystem is not persistent between reboot. Is there a way
> to change it, so that any change to file in the /etc will be
> persistent?

There's no easy way of doing that with our repo based builds I'm aware
of. The purpose of our (OP-TEE team) builds is in principle to be able
to execute xtest and other test programs. For this use case it's
actually an advantage to start from a clean state each time. In your
case I think you need to pick a suitable distribution and update it as
needed to support OP-TEE. It could be worth looking at Yocto as there
is some OP-TEE support already.

Here's a short list of what's needed:
1. TF-A compiled with OP-TEE support (dispatcher in BL31 and load
support in bl2)
2. OP-TEE included in the FIP loaded by TF-A
3. OP-TEE nodes in device tree
4. OP-TEE driver enabled in the kernel (recent upstream kernel should
work in most cases)
5. tee-supplicant and libteec.so installed in the file system
6. tee-supplicant started

With that in place you should be good to go.

Cheers,
Jens

Re: [Tee-dev] Persistent filesystem between reboots

[Joakim Bech]

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On Fri, Jan 15, 2021 at 12:50:27PM +0000, Jens Wiklander via OP-TEE wrote:
> Hi Kris,
> 
> On Thu, Jan 14, 2021 at 1:37 PM Kris Kwiatkowski <kris@amongbytes.com> wrote:
> >
> > Hi,
> >
> > I'm using HiKey 960 for my research project. I've noticed that
> > filesystem is not persistent between reboot. Is there a way
> > to change it, so that any change to file in the /etc will be
> > persistent?
> 
> There's no easy way of doing that with our repo based builds I'm aware
> of. The purpose of our (OP-TEE team) builds is in principle to be able
> to execute xtest and other test programs. For this use case it's
> actually an advantage to start from a clean state each time. In your
> case I think you need to pick a suitable distribution and update it as
> needed to support OP-TEE. It could be worth looking at Yocto as there
> is some OP-TEE support already.
> 
You can also give NFS a try, I tend to use that myself when playing with
OP-TEE and Raspberry Pi3. I.e., I basically just untar the rootfs
created by our setup into a folder that is exposed via NFS. Then in
addition to that I have a couple of helper scripts that copies the files
Jens mentioned below into that NFS folder when I need to update with
changed files (TA's, OP-TEE libs etc).

> Here's a short list of what's needed:
> 1. TF-A compiled with OP-TEE support (dispatcher in BL31 and load
> support in bl2)
> 2. OP-TEE included in the FIP loaded by TF-A
> 3. OP-TEE nodes in device tree
> 4. OP-TEE driver enabled in the kernel (recent upstream kernel should
> work in most cases)
> 5. tee-supplicant and libteec.so installed in the file system
> 6. tee-supplicant started
> 
> With that in place you should be good to go.
> 
> Cheers,
> Jens

-- 
Regards,
Joakim