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authorLinus Torvalds <torvalds@linux-foundation.org>2017-05-10 11:20:09 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2017-05-10 11:20:09 -0700
commita2d9214c730f54ff72c2940bcd7f22d1fccb26ec (patch)
treea50a1187ebba2c345213f27b4372939a3f39987b /drivers/tee/optee/optee_smc.h
parentMerge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip (diff)
parentMerge tag 'tee-drv-for-4.12' of git://git.linaro.org:/people/jens.wiklander/linux-tee into next/tee (diff)
downloadlinux-dev-a2d9214c730f54ff72c2940bcd7f22d1fccb26ec.tar.xz
linux-dev-a2d9214c730f54ff72c2940bcd7f22d1fccb26ec.zip
Merge tag 'armsoc-tee' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull TEE driver infrastructure and OP-TEE drivers from Arnd Bergmann: "This introduces a generic TEE framework in the kernel, to handle trusted environemtns (security coprocessor or software implementations such as OP-TEE/TrustZone). I'm sending it separately from the other arm-soc driver changes to give it a little more visibility, once the subsystem is merged, we will likely keep this in the armâ‚‹soc drivers branch or have the maintainers submit pull requests directly, depending on the patch volume. I have reviewed earlier versions in the past, and have reviewed the latest version in person during Linaro Connect BUD17. Here is my overall assessment of the subsystem: - There is clearly demand for this, both for the generic infrastructure and the specific OP-TEE implementation. - The code has gone through a large number of reviews, and the review comments have all been addressed, but the reviews were not coming up with serious issues any more and nobody volunteered to vouch for the quality. - The user space ioctl interface is sufficient to work with the OP-TEE driver, and it should in principle work with other TEE implementations that follow the GlobalPlatform[1] standards, but it might need to be extended in minor ways depending on specific requirements of future TEE implementations - The main downside of the API to me is how the user space is tied to the TEE implementation in hardware or firmware, but uses a generic way to communicate with it. This seems to be an inherent problem with what it is trying to do, and I could not come up with any better solution than what is implemented here. For a detailed history of the patch series, see https://lkml.org/lkml/2017/3/10/1277" * tag 'armsoc-tee' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: arm64: dt: hikey: Add optee node Documentation: tee subsystem and op-tee driver tee: add OP-TEE driver tee: generic TEE subsystem dt/bindings: add bindings for optee
Diffstat (limited to 'drivers/tee/optee/optee_smc.h')
-rw-r--r--drivers/tee/optee/optee_smc.h450
1 files changed, 450 insertions, 0 deletions
diff --git a/drivers/tee/optee/optee_smc.h b/drivers/tee/optee/optee_smc.h
new file mode 100644
index 000000000000..13b7c98cdf25
--- /dev/null
+++ b/drivers/tee/optee/optee_smc.h
@@ -0,0 +1,450 @@
+/*
+ * Copyright (c) 2015-2016, Linaro Limited
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ * this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+#ifndef OPTEE_SMC_H
+#define OPTEE_SMC_H
+
+#include <linux/arm-smccc.h>
+#include <linux/bitops.h>
+
+#define OPTEE_SMC_STD_CALL_VAL(func_num) \
+ ARM_SMCCC_CALL_VAL(ARM_SMCCC_STD_CALL, ARM_SMCCC_SMC_32, \
+ ARM_SMCCC_OWNER_TRUSTED_OS, (func_num))
+#define OPTEE_SMC_FAST_CALL_VAL(func_num) \
+ ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, ARM_SMCCC_SMC_32, \
+ ARM_SMCCC_OWNER_TRUSTED_OS, (func_num))
+
+/*
+ * Function specified by SMC Calling convention.
+ */
+#define OPTEE_SMC_FUNCID_CALLS_COUNT 0xFF00
+#define OPTEE_SMC_CALLS_COUNT \
+ ARM_SMCCC_CALL_VAL(OPTEE_SMC_FAST_CALL, SMCCC_SMC_32, \
+ SMCCC_OWNER_TRUSTED_OS_END, \
+ OPTEE_SMC_FUNCID_CALLS_COUNT)
+
+/*
+ * Normal cached memory (write-back), shareable for SMP systems and not
+ * shareable for UP systems.
+ */
+#define OPTEE_SMC_SHM_CACHED 1
+
+/*
+ * a0..a7 is used as register names in the descriptions below, on arm32
+ * that translates to r0..r7 and on arm64 to w0..w7. In both cases it's
+ * 32-bit registers.
+ */
+
+/*
+ * Function specified by SMC Calling convention
+ *
+ * Return one of the following UIDs if using API specified in this file
+ * without further extentions:
+ * 65cb6b93-af0c-4617-8ed6-644a8d1140f8
+ * see also OPTEE_SMC_UID_* in optee_msg.h
+ */
+#define OPTEE_SMC_FUNCID_CALLS_UID OPTEE_MSG_FUNCID_CALLS_UID
+#define OPTEE_SMC_CALLS_UID \
+ ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, ARM_SMCCC_SMC_32, \
+ ARM_SMCCC_OWNER_TRUSTED_OS_END, \
+ OPTEE_SMC_FUNCID_CALLS_UID)
+
+/*
+ * Function specified by SMC Calling convention
+ *
+ * Returns 2.0 if using API specified in this file without further extentions.
+ * see also OPTEE_MSG_REVISION_* in optee_msg.h
+ */
+#define OPTEE_SMC_FUNCID_CALLS_REVISION OPTEE_MSG_FUNCID_CALLS_REVISION
+#define OPTEE_SMC_CALLS_REVISION \
+ ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, ARM_SMCCC_SMC_32, \
+ ARM_SMCCC_OWNER_TRUSTED_OS_END, \
+ OPTEE_SMC_FUNCID_CALLS_REVISION)
+
+struct optee_smc_calls_revision_result {
+ unsigned long major;
+ unsigned long minor;
+ unsigned long reserved0;
+ unsigned long reserved1;
+};
+
+/*
+ * Get UUID of Trusted OS.
+ *
+ * Used by non-secure world to figure out which Trusted OS is installed.
+ * Note that returned UUID is the UUID of the Trusted OS, not of the API.
+ *
+ * Returns UUID in a0-4 in the same way as OPTEE_SMC_CALLS_UID
+ * described above.
+ */
+#define OPTEE_SMC_FUNCID_GET_OS_UUID OPTEE_MSG_FUNCID_GET_OS_UUID
+#define OPTEE_SMC_CALL_GET_OS_UUID \
+ OPTEE_SMC_FAST_CALL_VAL(OPTEE_SMC_FUNCID_GET_OS_UUID)
+
+/*
+ * Get revision of Trusted OS.
+ *
+ * Used by non-secure world to figure out which version of the Trusted OS
+ * is installed. Note that the returned revision is the revision of the
+ * Trusted OS, not of the API.
+ *
+ * Returns revision in a0-1 in the same way as OPTEE_SMC_CALLS_REVISION
+ * described above.
+ */
+#define OPTEE_SMC_FUNCID_GET_OS_REVISION OPTEE_MSG_FUNCID_GET_OS_REVISION
+#define OPTEE_SMC_CALL_GET_OS_REVISION \
+ OPTEE_SMC_FAST_CALL_VAL(OPTEE_SMC_FUNCID_GET_OS_REVISION)
+
+/*
+ * Call with struct optee_msg_arg as argument
+ *
+ * Call register usage:
+ * a0 SMC Function ID, OPTEE_SMC*CALL_WITH_ARG
+ * a1 Upper 32bit of a 64bit physical pointer to a struct optee_msg_arg
+ * a2 Lower 32bit of a 64bit physical pointer to a struct optee_msg_arg
+ * a3 Cache settings, not used if physical pointer is in a predefined shared
+ * memory area else per OPTEE_SMC_SHM_*
+ * a4-6 Not used
+ * a7 Hypervisor Client ID register
+ *
+ * Normal return register usage:
+ * a0 Return value, OPTEE_SMC_RETURN_*
+ * a1-3 Not used
+ * a4-7 Preserved
+ *
+ * OPTEE_SMC_RETURN_ETHREAD_LIMIT return register usage:
+ * a0 Return value, OPTEE_SMC_RETURN_ETHREAD_LIMIT
+ * a1-3 Preserved
+ * a4-7 Preserved
+ *
+ * RPC return register usage:
+ * a0 Return value, OPTEE_SMC_RETURN_IS_RPC(val)
+ * a1-2 RPC parameters
+ * a3-7 Resume information, must be preserved
+ *
+ * Possible return values:
+ * OPTEE_SMC_RETURN_UNKNOWN_FUNCTION Trusted OS does not recognize this
+ * function.
+ * OPTEE_SMC_RETURN_OK Call completed, result updated in
+ * the previously supplied struct
+ * optee_msg_arg.
+ * OPTEE_SMC_RETURN_ETHREAD_LIMIT Number of Trusted OS threads exceeded,
+ * try again later.
+ * OPTEE_SMC_RETURN_EBADADDR Bad physcial pointer to struct
+ * optee_msg_arg.
+ * OPTEE_SMC_RETURN_EBADCMD Bad/unknown cmd in struct optee_msg_arg
+ * OPTEE_SMC_RETURN_IS_RPC() Call suspended by RPC call to normal
+ * world.
+ */
+#define OPTEE_SMC_FUNCID_CALL_WITH_ARG OPTEE_MSG_FUNCID_CALL_WITH_ARG
+#define OPTEE_SMC_CALL_WITH_ARG \
+ OPTEE_SMC_STD_CALL_VAL(OPTEE_SMC_FUNCID_CALL_WITH_ARG)
+
+/*
+ * Get Shared Memory Config
+ *
+ * Returns the Secure/Non-secure shared memory config.
+ *
+ * Call register usage:
+ * a0 SMC Function ID, OPTEE_SMC_GET_SHM_CONFIG
+ * a1-6 Not used
+ * a7 Hypervisor Client ID register
+ *
+ * Have config return register usage:
+ * a0 OPTEE_SMC_RETURN_OK
+ * a1 Physical address of start of SHM
+ * a2 Size of of SHM
+ * a3 Cache settings of memory, as defined by the
+ * OPTEE_SMC_SHM_* values above
+ * a4-7 Preserved
+ *
+ * Not available register usage:
+ * a0 OPTEE_SMC_RETURN_ENOTAVAIL
+ * a1-3 Not used
+ * a4-7 Preserved
+ */
+#define OPTEE_SMC_FUNCID_GET_SHM_CONFIG 7
+#define OPTEE_SMC_GET_SHM_CONFIG \
+ OPTEE_SMC_FAST_CALL_VAL(OPTEE_SMC_FUNCID_GET_SHM_CONFIG)
+
+struct optee_smc_get_shm_config_result {
+ unsigned long status;
+ unsigned long start;
+ unsigned long size;
+ unsigned long settings;
+};
+
+/*
+ * Exchanges capabilities between normal world and secure world
+ *
+ * Call register usage:
+ * a0 SMC Function ID, OPTEE_SMC_EXCHANGE_CAPABILITIES
+ * a1 bitfield of normal world capabilities OPTEE_SMC_NSEC_CAP_*
+ * a2-6 Not used
+ * a7 Hypervisor Client ID register
+ *
+ * Normal return register usage:
+ * a0 OPTEE_SMC_RETURN_OK
+ * a1 bitfield of secure world capabilities OPTEE_SMC_SEC_CAP_*
+ * a2-7 Preserved
+ *
+ * Error return register usage:
+ * a0 OPTEE_SMC_RETURN_ENOTAVAIL, can't use the capabilities from normal world
+ * a1 bitfield of secure world capabilities OPTEE_SMC_SEC_CAP_*
+ * a2-7 Preserved
+ */
+/* Normal world works as a uniprocessor system */
+#define OPTEE_SMC_NSEC_CAP_UNIPROCESSOR BIT(0)
+/* Secure world has reserved shared memory for normal world to use */
+#define OPTEE_SMC_SEC_CAP_HAVE_RESERVED_SHM BIT(0)
+/* Secure world can communicate via previously unregistered shared memory */
+#define OPTEE_SMC_SEC_CAP_UNREGISTERED_SHM BIT(1)
+#define OPTEE_SMC_FUNCID_EXCHANGE_CAPABILITIES 9
+#define OPTEE_SMC_EXCHANGE_CAPABILITIES \
+ OPTEE_SMC_FAST_CALL_VAL(OPTEE_SMC_FUNCID_EXCHANGE_CAPABILITIES)
+
+struct optee_smc_exchange_capabilities_result {
+ unsigned long status;
+ unsigned long capabilities;
+ unsigned long reserved0;
+ unsigned long reserved1;
+};
+
+/*
+ * Disable and empties cache of shared memory objects
+ *
+ * Secure world can cache frequently used shared memory objects, for
+ * example objects used as RPC arguments. When secure world is idle this
+ * function returns one shared memory reference to free. To disable the
+ * cache and free all cached objects this function has to be called until
+ * it returns OPTEE_SMC_RETURN_ENOTAVAIL.
+ *
+ * Call register usage:
+ * a0 SMC Function ID, OPTEE_SMC_DISABLE_SHM_CACHE
+ * a1-6 Not used
+ * a7 Hypervisor Client ID register
+ *
+ * Normal return register usage:
+ * a0 OPTEE_SMC_RETURN_OK
+ * a1 Upper 32bit of a 64bit Shared memory cookie
+ * a2 Lower 32bit of a 64bit Shared memory cookie
+ * a3-7 Preserved
+ *
+ * Cache empty return register usage:
+ * a0 OPTEE_SMC_RETURN_ENOTAVAIL
+ * a1-7 Preserved
+ *
+ * Not idle return register usage:
+ * a0 OPTEE_SMC_RETURN_EBUSY
+ * a1-7 Preserved
+ */
+#define OPTEE_SMC_FUNCID_DISABLE_SHM_CACHE 10
+#define OPTEE_SMC_DISABLE_SHM_CACHE \
+ OPTEE_SMC_FAST_CALL_VAL(OPTEE_SMC_FUNCID_DISABLE_SHM_CACHE)
+
+struct optee_smc_disable_shm_cache_result {
+ unsigned long status;
+ unsigned long shm_upper32;
+ unsigned long shm_lower32;
+ unsigned long reserved0;
+};
+
+/*
+ * Enable cache of shared memory objects
+ *
+ * Secure world can cache frequently used shared memory objects, for
+ * example objects used as RPC arguments. When secure world is idle this
+ * function returns OPTEE_SMC_RETURN_OK and the cache is enabled. If
+ * secure world isn't idle OPTEE_SMC_RETURN_EBUSY is returned.
+ *
+ * Call register usage:
+ * a0 SMC Function ID, OPTEE_SMC_ENABLE_SHM_CACHE
+ * a1-6 Not used
+ * a7 Hypervisor Client ID register
+ *
+ * Normal return register usage:
+ * a0 OPTEE_SMC_RETURN_OK
+ * a1-7 Preserved
+ *
+ * Not idle return register usage:
+ * a0 OPTEE_SMC_RETURN_EBUSY
+ * a1-7 Preserved
+ */
+#define OPTEE_SMC_FUNCID_ENABLE_SHM_CACHE 11
+#define OPTEE_SMC_ENABLE_SHM_CACHE \
+ OPTEE_SMC_FAST_CALL_VAL(OPTEE_SMC_FUNCID_ENABLE_SHM_CACHE)
+
+/*
+ * Resume from RPC (for example after processing an IRQ)
+ *
+ * Call register usage:
+ * a0 SMC Function ID, OPTEE_SMC_CALL_RETURN_FROM_RPC
+ * a1-3 Value of a1-3 when OPTEE_SMC_CALL_WITH_ARG returned
+ * OPTEE_SMC_RETURN_RPC in a0
+ *
+ * Return register usage is the same as for OPTEE_SMC_*CALL_WITH_ARG above.
+ *
+ * Possible return values
+ * OPTEE_SMC_RETURN_UNKNOWN_FUNCTION Trusted OS does not recognize this
+ * function.
+ * OPTEE_SMC_RETURN_OK Original call completed, result
+ * updated in the previously supplied.
+ * struct optee_msg_arg
+ * OPTEE_SMC_RETURN_RPC Call suspended by RPC call to normal
+ * world.
+ * OPTEE_SMC_RETURN_ERESUME Resume failed, the opaque resume
+ * information was corrupt.
+ */
+#define OPTEE_SMC_FUNCID_RETURN_FROM_RPC 3
+#define OPTEE_SMC_CALL_RETURN_FROM_RPC \
+ OPTEE_SMC_STD_CALL_VAL(OPTEE_SMC_FUNCID_RETURN_FROM_RPC)
+
+#define OPTEE_SMC_RETURN_RPC_PREFIX_MASK 0xFFFF0000
+#define OPTEE_SMC_RETURN_RPC_PREFIX 0xFFFF0000
+#define OPTEE_SMC_RETURN_RPC_FUNC_MASK 0x0000FFFF
+
+#define OPTEE_SMC_RETURN_GET_RPC_FUNC(ret) \
+ ((ret) & OPTEE_SMC_RETURN_RPC_FUNC_MASK)
+
+#define OPTEE_SMC_RPC_VAL(func) ((func) | OPTEE_SMC_RETURN_RPC_PREFIX)
+
+/*
+ * Allocate memory for RPC parameter passing. The memory is used to hold a
+ * struct optee_msg_arg.
+ *
+ * "Call" register usage:
+ * a0 This value, OPTEE_SMC_RETURN_RPC_ALLOC
+ * a1 Size in bytes of required argument memory
+ * a2 Not used
+ * a3 Resume information, must be preserved
+ * a4-5 Not used
+ * a6-7 Resume information, must be preserved
+ *
+ * "Return" register usage:
+ * a0 SMC Function ID, OPTEE_SMC_CALL_RETURN_FROM_RPC.
+ * a1 Upper 32bits of 64bit physical pointer to allocated
+ * memory, (a1 == 0 && a2 == 0) if size was 0 or if memory can't
+ * be allocated.
+ * a2 Lower 32bits of 64bit physical pointer to allocated
+ * memory, (a1 == 0 && a2 == 0) if size was 0 or if memory can't
+ * be allocated
+ * a3 Preserved
+ * a4 Upper 32bits of 64bit Shared memory cookie used when freeing
+ * the memory or doing an RPC
+ * a5 Lower 32bits of 64bit Shared memory cookie used when freeing
+ * the memory or doing an RPC
+ * a6-7 Preserved
+ */
+#define OPTEE_SMC_RPC_FUNC_ALLOC 0
+#define OPTEE_SMC_RETURN_RPC_ALLOC \
+ OPTEE_SMC_RPC_VAL(OPTEE_SMC_RPC_FUNC_ALLOC)
+
+/*
+ * Free memory previously allocated by OPTEE_SMC_RETURN_RPC_ALLOC
+ *
+ * "Call" register usage:
+ * a0 This value, OPTEE_SMC_RETURN_RPC_FREE
+ * a1 Upper 32bits of 64bit shared memory cookie belonging to this
+ * argument memory
+ * a2 Lower 32bits of 64bit shared memory cookie belonging to this
+ * argument memory
+ * a3-7 Resume information, must be preserved
+ *
+ * "Return" register usage:
+ * a0 SMC Function ID, OPTEE_SMC_CALL_RETURN_FROM_RPC.
+ * a1-2 Not used
+ * a3-7 Preserved
+ */
+#define OPTEE_SMC_RPC_FUNC_FREE 2
+#define OPTEE_SMC_RETURN_RPC_FREE \
+ OPTEE_SMC_RPC_VAL(OPTEE_SMC_RPC_FUNC_FREE)
+
+/*
+ * Deliver an IRQ in normal world.
+ *
+ * "Call" register usage:
+ * a0 OPTEE_SMC_RETURN_RPC_IRQ
+ * a1-7 Resume information, must be preserved
+ *
+ * "Return" register usage:
+ * a0 SMC Function ID, OPTEE_SMC_CALL_RETURN_FROM_RPC.
+ * a1-7 Preserved
+ */
+#define OPTEE_SMC_RPC_FUNC_IRQ 4
+#define OPTEE_SMC_RETURN_RPC_IRQ \
+ OPTEE_SMC_RPC_VAL(OPTEE_SMC_RPC_FUNC_IRQ)
+
+/*
+ * Do an RPC request. The supplied struct optee_msg_arg tells which
+ * request to do and the parameters for the request. The following fields
+ * are used (the rest are unused):
+ * - cmd the Request ID
+ * - ret return value of the request, filled in by normal world
+ * - num_params number of parameters for the request
+ * - params the parameters
+ * - param_attrs attributes of the parameters
+ *
+ * "Call" register usage:
+ * a0 OPTEE_SMC_RETURN_RPC_CMD
+ * a1 Upper 32bit of a 64bit Shared memory cookie holding a
+ * struct optee_msg_arg, must be preserved, only the data should
+ * be updated
+ * a2 Lower 32bit of a 64bit Shared memory cookie holding a
+ * struct optee_msg_arg, must be preserved, only the data should
+ * be updated
+ * a3-7 Resume information, must be preserved
+ *
+ * "Return" register usage:
+ * a0 SMC Function ID, OPTEE_SMC_CALL_RETURN_FROM_RPC.
+ * a1-2 Not used
+ * a3-7 Preserved
+ */
+#define OPTEE_SMC_RPC_FUNC_CMD 5
+#define OPTEE_SMC_RETURN_RPC_CMD \
+ OPTEE_SMC_RPC_VAL(OPTEE_SMC_RPC_FUNC_CMD)
+
+/* Returned in a0 */
+#define OPTEE_SMC_RETURN_UNKNOWN_FUNCTION 0xFFFFFFFF
+
+/* Returned in a0 only from Trusted OS functions */
+#define OPTEE_SMC_RETURN_OK 0x0
+#define OPTEE_SMC_RETURN_ETHREAD_LIMIT 0x1
+#define OPTEE_SMC_RETURN_EBUSY 0x2
+#define OPTEE_SMC_RETURN_ERESUME 0x3
+#define OPTEE_SMC_RETURN_EBADADDR 0x4
+#define OPTEE_SMC_RETURN_EBADCMD 0x5
+#define OPTEE_SMC_RETURN_ENOMEM 0x6
+#define OPTEE_SMC_RETURN_ENOTAVAIL 0x7
+#define OPTEE_SMC_RETURN_IS_RPC(ret) __optee_smc_return_is_rpc((ret))
+
+static inline bool __optee_smc_return_is_rpc(u32 ret)
+{
+ return ret != OPTEE_SMC_RETURN_UNKNOWN_FUNCTION &&
+ (ret & OPTEE_SMC_RETURN_RPC_PREFIX_MASK) ==
+ OPTEE_SMC_RETURN_RPC_PREFIX;
+}
+
+#endif /* OPTEE_SMC_H */