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_msg.h b/drivers/tee/optee/optee_msg.h
new file mode 100644
index 0000000..24c6096
--- /dev/null
+++ b/drivers/tee/optee/optee_msg.h
@@ -0,0 +1,425 @@
+/* SPDX-License-Identifier: BSD-2-Clause */
+/*
+ * Copyright (c) 2015-2018, Linaro Limited
+ */
+
+#ifndef _OPTEE_MSG_H
+#define _OPTEE_MSG_H
+
+#include <linux/bitops.h>
+#include <linux/types.h>
+
+/*
+ * This file defines the OP-TEE message protocol used to communicate with
+ * an instance of OP-TEE running in secure world. This file is based on
+ * https://github.com/OP-TEE/optee_os/blob/master/core/include/optee_msg.h
+ * and may need to be updated when introducing new features.
+ *
+ * This file is divided into three sections.
+ * 1. Formatting of messages.
+ * 2. Requests from normal world
+ * 3. Requests from secure world, Remote Procedure Call (RPC), handled by
+ *    tee-supplicant.
+ */
+
+/*****************************************************************************
+ * Part 1 - formatting of messages
+ *****************************************************************************/
+
+#define OPTEE_MSG_ATTR_TYPE_NONE		0x0
+#define OPTEE_MSG_ATTR_TYPE_VALUE_INPUT		0x1
+#define OPTEE_MSG_ATTR_TYPE_VALUE_OUTPUT	0x2
+#define OPTEE_MSG_ATTR_TYPE_VALUE_INOUT		0x3
+#define OPTEE_MSG_ATTR_TYPE_RMEM_INPUT		0x5
+#define OPTEE_MSG_ATTR_TYPE_RMEM_OUTPUT		0x6
+#define OPTEE_MSG_ATTR_TYPE_RMEM_INOUT		0x7
+#define OPTEE_MSG_ATTR_TYPE_TMEM_INPUT		0x9
+#define OPTEE_MSG_ATTR_TYPE_TMEM_OUTPUT		0xa
+#define OPTEE_MSG_ATTR_TYPE_TMEM_INOUT		0xb
+
+#define OPTEE_MSG_ATTR_TYPE_MASK		GENMASK(7, 0)
+
+/*
+ * Meta parameter to be absorbed by the Secure OS and not passed
+ * to the Trusted Application.
+ *
+ * Currently only used with OPTEE_MSG_CMD_OPEN_SESSION.
+ */
+#define OPTEE_MSG_ATTR_META			BIT(8)
+
+/*
+ * Pointer to a list of pages used to register user-defined SHM buffer.
+ * Used with OPTEE_MSG_ATTR_TYPE_TMEM_*.
+ * buf_ptr should point to the beginning of the buffer. Buffer will contain
+ * list of page addresses. OP-TEE core can reconstruct contiguous buffer from
+ * that page addresses list. Page addresses are stored as 64 bit values.
+ * Last entry on a page should point to the next page of buffer.
+ * Every entry in buffer should point to a 4k page beginning (12 least
+ * significant bits must be equal to zero).
+ *
+ * 12 least significant bints of optee_msg_param.u.tmem.buf_ptr should hold page
+ * offset of the user buffer.
+ *
+ * So, entries should be placed like members of this structure:
+ *
+ * struct page_data {
+ *   uint64_t pages_array[OPTEE_MSG_NONCONTIG_PAGE_SIZE/sizeof(uint64_t) - 1];
+ *   uint64_t next_page_data;
+ * };
+ *
+ * Structure is designed to exactly fit into the page size
+ * OPTEE_MSG_NONCONTIG_PAGE_SIZE which is a standard 4KB page.
+ *
+ * The size of 4KB is chosen because this is the smallest page size for ARM
+ * architectures. If REE uses larger pages, it should divide them to 4KB ones.
+ */
+#define OPTEE_MSG_ATTR_NONCONTIG		BIT(9)
+
+/*
+ * Memory attributes for caching passed with temp memrefs. The actual value
+ * used is defined outside the message protocol with the exception of
+ * OPTEE_MSG_ATTR_CACHE_PREDEFINED which means the attributes already
+ * defined for the memory range should be used. If optee_smc.h is used as
+ * bearer of this protocol OPTEE_SMC_SHM_* is used for values.
+ */
+#define OPTEE_MSG_ATTR_CACHE_SHIFT		16
+#define OPTEE_MSG_ATTR_CACHE_MASK		GENMASK(2, 0)
+#define OPTEE_MSG_ATTR_CACHE_PREDEFINED		0
+
+/*
+ * Same values as TEE_LOGIN_* from TEE Internal API
+ */
+#define OPTEE_MSG_LOGIN_PUBLIC			0x00000000
+#define OPTEE_MSG_LOGIN_USER			0x00000001
+#define OPTEE_MSG_LOGIN_GROUP			0x00000002
+#define OPTEE_MSG_LOGIN_APPLICATION		0x00000004
+#define OPTEE_MSG_LOGIN_APPLICATION_USER	0x00000005
+#define OPTEE_MSG_LOGIN_APPLICATION_GROUP	0x00000006
+
+/*
+ * Page size used in non-contiguous buffer entries
+ */
+#define OPTEE_MSG_NONCONTIG_PAGE_SIZE		4096
+
+/**
+ * struct optee_msg_param_tmem - temporary memory reference parameter
+ * @buf_ptr:	Address of the buffer
+ * @size:	Size of the buffer
+ * @shm_ref:	Temporary shared memory reference, pointer to a struct tee_shm
+ *
+ * Secure and normal world communicates pointers as physical address
+ * instead of the virtual address. This is because secure and normal world
+ * have completely independent memory mapping. Normal world can even have a
+ * hypervisor which need to translate the guest physical address (AKA IPA
+ * in ARM documentation) to a real physical address before passing the
+ * structure to secure world.
+ */
+struct optee_msg_param_tmem {
+	u64 buf_ptr;
+	u64 size;
+	u64 shm_ref;
+};
+
+/**
+ * struct optee_msg_param_rmem - registered memory reference parameter
+ * @offs:	Offset into shared memory reference
+ * @size:	Size of the buffer
+ * @shm_ref:	Shared memory reference, pointer to a struct tee_shm
+ */
+struct optee_msg_param_rmem {
+	u64 offs;
+	u64 size;
+	u64 shm_ref;
+};
+
+/**
+ * struct optee_msg_param_value - opaque value parameter
+ *
+ * Value parameters are passed unchecked between normal and secure world.
+ */
+struct optee_msg_param_value {
+	u64 a;
+	u64 b;
+	u64 c;
+};
+
+/**
+ * struct optee_msg_param - parameter used together with struct optee_msg_arg
+ * @attr:	attributes
+ * @tmem:	parameter by temporary memory reference
+ * @rmem:	parameter by registered memory reference
+ * @value:	parameter by opaque value
+ *
+ * @attr & OPTEE_MSG_ATTR_TYPE_MASK indicates if tmem, rmem or value is used in
+ * the union. OPTEE_MSG_ATTR_TYPE_VALUE_* indicates value,
+ * OPTEE_MSG_ATTR_TYPE_TMEM_* indicates @tmem and
+ * OPTEE_MSG_ATTR_TYPE_RMEM_* indicates @rmem,
+ * OPTEE_MSG_ATTR_TYPE_NONE indicates that none of the members are used.
+ */
+struct optee_msg_param {
+	u64 attr;
+	union {
+		struct optee_msg_param_tmem tmem;
+		struct optee_msg_param_rmem rmem;
+		struct optee_msg_param_value value;
+	} u;
+};
+
+/**
+ * struct optee_msg_arg - call argument
+ * @cmd: Command, one of OPTEE_MSG_CMD_* or OPTEE_MSG_RPC_CMD_*
+ * @func: Trusted Application function, specific to the Trusted Application,
+ *	     used if cmd == OPTEE_MSG_CMD_INVOKE_COMMAND
+ * @session: In parameter for all OPTEE_MSG_CMD_* except
+ *	     OPTEE_MSG_CMD_OPEN_SESSION where it's an output parameter instead
+ * @cancel_id: Cancellation id, a unique value to identify this request
+ * @ret: return value
+ * @ret_origin: origin of the return value
+ * @num_params: number of parameters supplied to the OS Command
+ * @params: the parameters supplied to the OS Command
+ *
+ * All normal calls to Trusted OS uses this struct. If cmd requires further
+ * information than what these field holds it can be passed as a parameter
+ * tagged as meta (setting the OPTEE_MSG_ATTR_META bit in corresponding
+ * attrs field). All parameters tagged as meta has to come first.
+ *
+ * Temp memref parameters can be fragmented if supported by the Trusted OS
+ * (when optee_smc.h is bearer of this protocol this is indicated with
+ * OPTEE_SMC_SEC_CAP_UNREGISTERED_SHM). If a logical memref parameter is
+ * fragmented then has all but the last fragment the
+ * OPTEE_MSG_ATTR_FRAGMENT bit set in attrs. Even if a memref is fragmented
+ * it will still be presented as a single logical memref to the Trusted
+ * Application.
+ */
+struct optee_msg_arg {
+	u32 cmd;
+	u32 func;
+	u32 session;
+	u32 cancel_id;
+	u32 pad;
+	u32 ret;
+	u32 ret_origin;
+	u32 num_params;
+
+	/* num_params tells the actual number of element in params */
+	struct optee_msg_param params[0];
+};
+
+/**
+ * OPTEE_MSG_GET_ARG_SIZE - return size of struct optee_msg_arg
+ *
+ * @num_params: Number of parameters embedded in the struct optee_msg_arg
+ *
+ * Returns the size of the struct optee_msg_arg together with the number
+ * of embedded parameters.
+ */
+#define OPTEE_MSG_GET_ARG_SIZE(num_params) \
+	(sizeof(struct optee_msg_arg) + \
+	 sizeof(struct optee_msg_param) * (num_params))
+
+/*****************************************************************************
+ * Part 2 - requests from normal world
+ *****************************************************************************/
+
+/*
+ * Return the following UID if using API specified in this file without
+ * further extensions:
+ * 384fb3e0-e7f8-11e3-af63-0002a5d5c51b.
+ * Represented in 4 32-bit words in OPTEE_MSG_UID_0, OPTEE_MSG_UID_1,
+ * OPTEE_MSG_UID_2, OPTEE_MSG_UID_3.
+ */
+#define OPTEE_MSG_UID_0			0x384fb3e0
+#define OPTEE_MSG_UID_1			0xe7f811e3
+#define OPTEE_MSG_UID_2			0xaf630002
+#define OPTEE_MSG_UID_3			0xa5d5c51b
+#define OPTEE_MSG_FUNCID_CALLS_UID	0xFF01
+
+/*
+ * Returns 2.0 if using API specified in this file without further
+ * extensions. Represented in 2 32-bit words in OPTEE_MSG_REVISION_MAJOR
+ * and OPTEE_MSG_REVISION_MINOR
+ */
+#define OPTEE_MSG_REVISION_MAJOR	2
+#define OPTEE_MSG_REVISION_MINOR	0
+#define OPTEE_MSG_FUNCID_CALLS_REVISION	0xFF03
+
+/*
+ * 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 4 32-bit words in the same way as
+ * OPTEE_MSG_FUNCID_CALLS_UID described above.
+ */
+#define OPTEE_MSG_OS_OPTEE_UUID_0	0x486178e0
+#define OPTEE_MSG_OS_OPTEE_UUID_1	0xe7f811e3
+#define OPTEE_MSG_OS_OPTEE_UUID_2	0xbc5e0002
+#define OPTEE_MSG_OS_OPTEE_UUID_3	0xa5d5c51b
+#define OPTEE_MSG_FUNCID_GET_OS_UUID	0x0000
+
+/*
+ * 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 2 32-bit words in the same way as
+ * OPTEE_MSG_CALLS_REVISION described above.
+ */
+#define OPTEE_MSG_FUNCID_GET_OS_REVISION	0x0001
+
+/*
+ * Do a secure call with struct optee_msg_arg as argument
+ * The OPTEE_MSG_CMD_* below defines what goes in struct optee_msg_arg::cmd
+ *
+ * OPTEE_MSG_CMD_OPEN_SESSION opens a session to a Trusted Application.
+ * The first two parameters are tagged as meta, holding two value
+ * parameters to pass the following information:
+ * param[0].u.value.a-b uuid of Trusted Application
+ * param[1].u.value.a-b uuid of Client
+ * param[1].u.value.c Login class of client OPTEE_MSG_LOGIN_*
+ *
+ * OPTEE_MSG_CMD_INVOKE_COMMAND invokes a command a previously opened
+ * session to a Trusted Application.  struct optee_msg_arg::func is Trusted
+ * Application function, specific to the Trusted Application.
+ *
+ * OPTEE_MSG_CMD_CLOSE_SESSION closes a previously opened session to
+ * Trusted Application.
+ *
+ * OPTEE_MSG_CMD_CANCEL cancels a currently invoked command.
+ *
+ * OPTEE_MSG_CMD_REGISTER_SHM registers a shared memory reference. The
+ * information is passed as:
+ * [in] param[0].attr			OPTEE_MSG_ATTR_TYPE_TMEM_INPUT
+ *					[| OPTEE_MSG_ATTR_FRAGMENT]
+ * [in] param[0].u.tmem.buf_ptr		physical address (of first fragment)
+ * [in] param[0].u.tmem.size		size (of first fragment)
+ * [in] param[0].u.tmem.shm_ref		holds shared memory reference
+ * ...
+ * The shared memory can optionally be fragmented, temp memrefs can follow
+ * each other with all but the last with the OPTEE_MSG_ATTR_FRAGMENT bit set.
+ *
+ * OPTEE_MSG_CMD_UNREGISTER_SHM unregisteres a previously registered shared
+ * memory reference. The information is passed as:
+ * [in] param[0].attr			OPTEE_MSG_ATTR_TYPE_RMEM_INPUT
+ * [in] param[0].u.rmem.shm_ref		holds shared memory reference
+ * [in] param[0].u.rmem.offs		0
+ * [in] param[0].u.rmem.size		0
+ */
+#define OPTEE_MSG_CMD_OPEN_SESSION	0
+#define OPTEE_MSG_CMD_INVOKE_COMMAND	1
+#define OPTEE_MSG_CMD_CLOSE_SESSION	2
+#define OPTEE_MSG_CMD_CANCEL		3
+#define OPTEE_MSG_CMD_REGISTER_SHM	4
+#define OPTEE_MSG_CMD_UNREGISTER_SHM	5
+#define OPTEE_MSG_FUNCID_CALL_WITH_ARG	0x0004
+
+/*****************************************************************************
+ * Part 3 - Requests from secure world, RPC
+ *****************************************************************************/
+
+/*
+ * All RPC is done with a struct optee_msg_arg as bearer of information,
+ * struct optee_msg_arg::arg holds values defined by OPTEE_MSG_RPC_CMD_* below
+ *
+ * RPC communication with tee-supplicant is reversed compared to normal
+ * client communication desribed above. The supplicant receives requests
+ * and sends responses.
+ */
+
+/*
+ * Load a TA into memory, defined in tee-supplicant
+ */
+#define OPTEE_MSG_RPC_CMD_LOAD_TA	0
+
+/*
+ * Reserved
+ */
+#define OPTEE_MSG_RPC_CMD_RPMB		1
+
+/*
+ * File system access, defined in tee-supplicant
+ */
+#define OPTEE_MSG_RPC_CMD_FS		2
+
+/*
+ * Get time
+ *
+ * Returns number of seconds and nano seconds since the Epoch,
+ * 1970-01-01 00:00:00 +0000 (UTC).
+ *
+ * [out] param[0].u.value.a	Number of seconds
+ * [out] param[0].u.value.b	Number of nano seconds.
+ */
+#define OPTEE_MSG_RPC_CMD_GET_TIME	3
+
+/*
+ * Wait queue primitive, helper for secure world to implement a wait queue.
+ *
+ * If secure world need to wait for a secure world mutex it issues a sleep
+ * request instead of spinning in secure world. Conversely is a wakeup
+ * request issued when a secure world mutex with a thread waiting thread is
+ * unlocked.
+ *
+ * Waiting on a key
+ * [in] param[0].u.value.a OPTEE_MSG_RPC_WAIT_QUEUE_SLEEP
+ * [in] param[0].u.value.b wait key
+ *
+ * Waking up a key
+ * [in] param[0].u.value.a OPTEE_MSG_RPC_WAIT_QUEUE_WAKEUP
+ * [in] param[0].u.value.b wakeup key
+ */
+#define OPTEE_MSG_RPC_CMD_WAIT_QUEUE	4
+#define OPTEE_MSG_RPC_WAIT_QUEUE_SLEEP	0
+#define OPTEE_MSG_RPC_WAIT_QUEUE_WAKEUP	1
+
+/*
+ * Suspend execution
+ *
+ * [in] param[0].value	.a number of milliseconds to suspend
+ */
+#define OPTEE_MSG_RPC_CMD_SUSPEND	5
+
+/*
+ * Allocate a piece of shared memory
+ *
+ * Shared memory can optionally be fragmented, to support that additional
+ * spare param entries are allocated to make room for eventual fragments.
+ * The spare param entries has .attr = OPTEE_MSG_ATTR_TYPE_NONE when
+ * unused. All returned temp memrefs except the last should have the
+ * OPTEE_MSG_ATTR_FRAGMENT bit set in the attr field.
+ *
+ * [in]  param[0].u.value.a		type of memory one of
+ *					OPTEE_MSG_RPC_SHM_TYPE_* below
+ * [in]  param[0].u.value.b		requested size
+ * [in]  param[0].u.value.c		required alignment
+ *
+ * [out] param[0].u.tmem.buf_ptr	physical address (of first fragment)
+ * [out] param[0].u.tmem.size		size (of first fragment)
+ * [out] param[0].u.tmem.shm_ref	shared memory reference
+ * ...
+ * [out] param[n].u.tmem.buf_ptr	physical address
+ * [out] param[n].u.tmem.size		size
+ * [out] param[n].u.tmem.shm_ref	shared memory reference (same value
+ *					as in param[n-1].u.tmem.shm_ref)
+ */
+#define OPTEE_MSG_RPC_CMD_SHM_ALLOC	6
+/* Memory that can be shared with a non-secure user space application */
+#define OPTEE_MSG_RPC_SHM_TYPE_APPL	0
+/* Memory only shared with non-secure kernel */
+#define OPTEE_MSG_RPC_SHM_TYPE_KERNEL	1
+
+/*
+ * Free shared memory previously allocated with OPTEE_MSG_RPC_CMD_SHM_ALLOC
+ *
+ * [in]  param[0].u.value.a		type of memory one of
+ *					OPTEE_MSG_RPC_SHM_TYPE_* above
+ * [in]  param[0].u.value.b		value of shared memory reference
+ *					returned in param[0].u.tmem.shm_ref
+ *					above
+ */
+#define OPTEE_MSG_RPC_CMD_SHM_FREE	7
+
+#endif /* _OPTEE_MSG_H */