tee: add OP-TEE driver

Adds a OP-TEE driver.

* Targets ARM and ARM64
* Supports using any U-Boot memory as shared memory
* Probes OP-TEE version using SMCs
* Uses OPTEE message protocol version 2 to communicate with secure world

Reviewed-by: Simon Glass <sjg@chromium.org>
Tested-by: Igor Opaniuk <igor.opaniuk@linaro.org>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
diff --git a/drivers/tee/optee/optee_smc.h b/drivers/tee/optee/optee_smc.h
new file mode 100644
index 0000000..4d643b2
--- /dev/null
+++ b/drivers/tee/optee/optee_smc.h
@@ -0,0 +1,450 @@
+/* SPDX-License-Identifier: BSD-2-Clause */
+/*
+ * Copyright (c) 2015-2018, Linaro Limited
+ */
+
+#ifndef OPTEE_SMC_H
+#define OPTEE_SMC_H
+
+#include <linux/arm-smccc.h>
+#include <linux/bitops.h>
+
+/*
+ * This file is based on
+ * https://github.com/OP-TEE/optee_os/blob/master/core/arch/arm/include/sm/optee_smc.h
+ * and may need to be updated when introducing new features.
+ */
+
+#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. May optionally return a 32-bit build identifier in a2,
+ * with zero meaning unspecified.
+ */
+#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)
+
+struct optee_smc_call_get_os_revision_result {
+	unsigned long major;
+	unsigned long minor;
+	unsigned long build_id;
+	unsigned long reserved1;
+};
+
+/*
+ * 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)
+
+/*
+ * Secure world supports commands "register/unregister shared memory",
+ * secure world accepts command buffers located in any parts of non-secure RAM
+ */
+#define OPTEE_SMC_SEC_CAP_DYNAMIC_SHM		BIT(2)
+
+#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 a foreign interrupt)
+ *
+ * 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 foreign interrupt to normal world.
+ *
+ * "Call" register usage:
+ * a0	OPTEE_SMC_RETURN_RPC_FOREIGN_INTR
+ * 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_FOREIGN_INTR		4
+#define OPTEE_SMC_RETURN_RPC_FOREIGN_INTR \
+	OPTEE_SMC_RPC_VAL(OPTEE_SMC_RPC_FUNC_FOREIGN_INTR)
+
+/*
+ * 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 */