tee: add OP-TEE driver

Adds a OP-TEE driver which also can be compiled as a loadable module.

* Targets ARM and ARM64
* Supports using reserved memory from OP-TEE as shared memory
* Probes OP-TEE version using SMCs
* Accepts requests on privileged and unprivileged device
* Uses OPTEE message protocol version 2 to communicate with secure world

Acked-by: Andreas Dannenberg <dannenberg@ti.com>
Tested-by: Jerome Forissier <jerome.forissier@linaro.org> (HiKey)
Tested-by: Volodymyr Babchuk <vlad.babchuk@gmail.com> (RCAR H3)
Tested-by: Scott Branden <scott.branden@broadcom.com>
Reviewed-by: Javier González <javier@javigon.com>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
(cherry picked from commit 4fb0a5eb364d239722e745c02aef0dbd4e0f1ad2)
Signed-off-by: Alex Shi <alex.shi@linaro.org>

Author: jenswi-linaro

MAINTAINERS

@@ -7935,6 +7935,11 @@ F:	arch/*/oprofile/
 F:	drivers/oprofile/
 F:	include/linux/oprofile.h
 
+OP-TEE DRIVER
+M:	Jens Wiklander <jens.wiklander@linaro.org>
+S:	Maintained
+F:	drivers/tee/optee/
+
 ORACLE CLUSTER FILESYSTEM 2 (OCFS2)
 M:	Mark Fasheh <mfasheh@suse.com>
 M:	Joel Becker <jlbec@evilplan.org>

drivers/tee/Kconfig

@@ -6,3 +6,13 @@ config TEE
 	help
 	  This implements a generic interface towards a Trusted Execution
 	  Environment (TEE).
+
+if TEE
+
+menu "TEE drivers"
+
+source "drivers/tee/optee/Kconfig"
+
+endmenu
+
+endif

drivers/tee/Makefile

@@ -2,3 +2,4 @@ obj-$(CONFIG_TEE) += tee.o
 tee-objs += tee_core.o
 tee-objs += tee_shm.o
 tee-objs += tee_shm_pool.o
+obj-$(CONFIG_OPTEE) += optee/

drivers/tee/optee/Kconfig

@@ -0,0 +1,7 @@
+# OP-TEE Trusted Execution Environment Configuration
+config OPTEE
+	tristate "OP-TEE"
+	depends on HAVE_ARM_SMCCC
+	help
+	  This implements the OP-TEE Trusted Execution Environment (TEE)
+	  driver.

drivers/tee/optee/Makefile

@@ -0,0 +1,5 @@
+obj-$(CONFIG_OPTEE) += optee.o
+optee-objs += core.o
+optee-objs += call.o
+optee-objs += rpc.o
+optee-objs += supp.o