Re: [Tee-dev] eMMC driver in OP-TEE?

Le 22 nov. 2017 10:35 PM, "Stuart Yoder" stuart.yoder@arm.com a écrit :

On 11/22/17 2:53 PM, Jerome Forissier wrote:

Hi Stuart,

Le 22 nov. 2017 9:28 PM, "Stuart Yoder" <stuart.yoder@arm.com mailto: stuart.yoder@arm.com> a écrit :

There is no storage controller driver in OP-TEE, as pointed out in the

RPMB doc:

    There is no eMMC controller driver in OP-TEE. The device

operations all have to go through the normal world. They are handled by the tee-supplicant process which further relies on the kernel's ioctl() interface to access the device.

Correct.

Is doing this a roadmap (or potential roadmap) item for OP-TEE?

I don't think it is at the moment.

I'm wondering
what discussions might have happened in the past, and if the idea has

been rejected for some reason. Or, is it a potential future to do item?

There are some technical challenges, but we have certainly not rejected the idea!

Anything you can share about what you see the challenges being?

Sure. The main difficulty I see is how to share device/controller between Normal and Secure World (configuration via DT, synchronisation). Indeed, for some platforms it might not be reasonable to consider that SW has exclusive access? Then, there is the amount of code needed. Quite a lot AFAICT. Could we find some existing code with a BSD-compatible license?