[GIT PULL] TEE driver infrastructure and OP-TEE drivers

On Wed, May 10, 2017 at 8:55 PM, Linus Torvalds
[off-list ref] wrote:

On Tue, May 9, 2017 at 12:05 PM, Arnd Bergmann [off-list ref] wrote:

quoted

https://lkml.org/lkml/2017/3/10/1277

Oh well, that wasn't very useful right now..

Hopefully it comes back eventually. For now, the same contents are also at

https://lwn.net/Articles/716737/

quoted

TEE driver infrastructure and OP-TEE drivers

Another note: right now this adds a config question for TEE support,
but the only actual TEE driver has a

        depends on HAVE_ARM_SMCCC

on it.

Until we get more TEE drivers, might I suggest that we perhaps make
the TEE config option have

        depends on HAVE_ARM_SMCCC || COMPILE_TEST

so that the generic tee code still gets the compile test coverage, but
we don't confuse people by asking about infrastructure that they can't
possibly use..

Hmm?

Yes, good idea. I've added this patch to the arm-soc fixes branch that
already contains a couple of other things you will get in a few days:

From efd467ff4f611d67e9009de2391ce484f9436054 Mon Sep 17 00:00:00 2001

From: Arnd Bergmann <arnd@arndb.de>
Date: Wed, 10 May 2017 21:05:16 +0200
Subject: [PATCH] tee: add ARM_SMCCC dependency

For the moment, the tee subsystem only makes sense in combination with
the op-tee driver that depends on ARM_SMCCC, so let's hide the subsystem
from users that can't select that.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

diff --git a/drivers/tee/Kconfig b/drivers/tee/Kconfig
index 2330a4eb4e8b..2824398fc5d6 100644
--- a/drivers/tee/Kconfig
+++ b/drivers/tee/Kconfig

@@ -1,6 +1,7 @@
 # Generic Trusted Execution Environment Configuration
 config TEE
  tristate "Trusted Execution Environment support"
+ depends on HAVE_ARM_SMCCC || COMPILE_TEST # until we have more than one driver
  select DMA_SHARED_BUFFER
  select GENERIC_ALLOCATOR
  help