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 arm₋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

15 files changed, 4357 insertions, 0 deletions

diff --git a/drivers/tee/Kconfig b/drivers/tee/Kconfig
new file mode 100644
index 000000000000..2330a4eb4e8b
--- /dev/null
+++ b/drivers/tee/Kconfig
@@ -0,0 +1,18 @@
+# Generic Trusted Execution Environment Configuration
+config TEE
+	tristate "Trusted Execution Environment support"
+	select DMA_SHARED_BUFFER
+	select GENERIC_ALLOCATOR
+	help
+	  This implements a generic interface towards a Trusted Execution
+	  Environment (TEE).
+
+if TEE
+
+menu "TEE drivers"
+
+source "drivers/tee/optee/Kconfig"
+
+endmenu
+
+endif
diff --git a/drivers/tee/Makefile b/drivers/tee/Makefile
new file mode 100644
index 000000000000..7a4e4a1ac39c
--- /dev/null
+++ b/drivers/tee/Makefile
@@ -0,0 +1,5 @@
+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/
diff --git a/drivers/tee/optee/Kconfig b/drivers/tee/optee/Kconfig
new file mode 100644
index 000000000000..0126de898036
--- /dev/null
+++ b/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.
diff --git a/drivers/tee/optee/Makefile b/drivers/tee/optee/Makefile
new file mode 100644
index 000000000000..92fe5789bcce
--- /dev/null
+++ b/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
diff --git a/drivers/tee/optee/call.c b/drivers/tee/optee/call.c
new file mode 100644
index 000000000000..f7b7b404c990
--- /dev/null
+++ b/drivers/tee/optee/call.c
@@ -0,0 +1,444 @@
+/*
+ * Copyright (c) 2015, Linaro Limited
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+#include <linux/arm-smccc.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/errno.h>
+#include <linux/slab.h>
+#include <linux/tee_drv.h>
+#include <linux/types.h>
+#include <linux/uaccess.h>
+#include "optee_private.h"
+#include "optee_smc.h"
+
+struct optee_call_waiter {
+	struct list_head list_node;
+	struct completion c;
+};
+
+static void optee_cq_wait_init(struct optee_call_queue *cq,
+			       struct optee_call_waiter *w)
+{
+	/*
+	 * We're preparing to make a call to secure world. In case we can't
+	 * allocate a thread in secure world we'll end up waiting in
+	 * optee_cq_wait_for_completion().
+	 *
+	 * Normally if there's no contention in secure world the call will
+	 * complete and we can cleanup directly with optee_cq_wait_final().
+	 */
+	mutex_lock(&cq->mutex);
+
+	/*
+	 * We add ourselves to the queue, but we don't wait. This
+	 * guarantees that we don't lose a completion if secure world
+	 * returns busy and another thread just exited and try to complete
+	 * someone.
+	 */
+	init_completion(&w->c);
+	list_add_tail(&w->list_node, &cq->waiters);
+
+	mutex_unlock(&cq->mutex);
+}
+
+static void optee_cq_wait_for_completion(struct optee_call_queue *cq,
+					 struct optee_call_waiter *w)
+{
+	wait_for_completion(&w->c);
+
+	mutex_lock(&cq->mutex);
+
+	/* Move to end of list to get out of the way for other waiters */
+	list_del(&w->list_node);
+	reinit_completion(&w->c);
+	list_add_tail(&w->list_node, &cq->waiters);
+
+	mutex_unlock(&cq->mutex);
+}
+
+static void optee_cq_complete_one(struct optee_call_queue *cq)
+{
+	struct optee_call_waiter *w;
+
+	list_for_each_entry(w, &cq->waiters, list_node) {
+		if (!completion_done(&w->c)) {
+			complete(&w->c);
+			break;
+		}
+	}
+}
+
+static void optee_cq_wait_final(struct optee_call_queue *cq,
+				struct optee_call_waiter *w)
+{
+	/*
+	 * We're done with the call to secure world. The thread in secure
+	 * world that was used for this call is now available for some
+	 * other task to use.
+	 */
+	mutex_lock(&cq->mutex);
+
+	/* Get out of the list */
+	list_del(&w->list_node);
+
+	/* Wake up one eventual waiting task */
+	optee_cq_complete_one(cq);
+
+	/*
+	 * If we're completed we've got a completion from another task that
+	 * was just done with its call to secure world. Since yet another
+	 * thread now is available in secure world wake up another eventual
+	 * waiting task.
+	 */
+	if (completion_done(&w->c))
+		optee_cq_complete_one(cq);
+
+	mutex_unlock(&cq->mutex);
+}
+
+/* Requires the filpstate mutex to be held */
+static struct optee_session *find_session(struct optee_context_data *ctxdata,
+					  u32 session_id)
+{
+	struct optee_session *sess;
+
+	list_for_each_entry(sess, &ctxdata->sess_list, list_node)
+		if (sess->session_id == session_id)
+			return sess;
+
+	return NULL;
+}
+
+/**
+ * optee_do_call_with_arg() - Do an SMC to OP-TEE in secure world
+ * @ctx:	calling context
+ * @parg:	physical address of message to pass to secure world
+ *
+ * Does and SMC to OP-TEE in secure world and handles eventual resulting
+ * Remote Procedure Calls (RPC) from OP-TEE.
+ *
+ * Returns return code from secure world, 0 is OK
+ */
+u32 optee_do_call_with_arg(struct tee_context *ctx, phys_addr_t parg)
+{
+	struct optee *optee = tee_get_drvdata(ctx->teedev);
+	struct optee_call_waiter w;
+	struct optee_rpc_param param = { };
+	u32 ret;
+
+	param.a0 = OPTEE_SMC_CALL_WITH_ARG;
+	reg_pair_from_64(&param.a1, &param.a2, parg);
+	/* Initialize waiter */
+	optee_cq_wait_init(&optee->call_queue, &w);
+	while (true) {
+		struct arm_smccc_res res;
+
+		optee->invoke_fn(param.a0, param.a1, param.a2, param.a3,
+				 param.a4, param.a5, param.a6, param.a7,
+				 &res);
+
+		if (res.a0 == OPTEE_SMC_RETURN_ETHREAD_LIMIT) {
+			/*
+			 * Out of threads in secure world, wait for a thread
+			 * become available.
+			 */
+			optee_cq_wait_for_completion(&optee->call_queue, &w);
+		} else if (OPTEE_SMC_RETURN_IS_RPC(res.a0)) {
+			param.a0 = res.a0;
+			param.a1 = res.a1;
+			param.a2 = res.a2;
+			param.a3 = res.a3;
+			optee_handle_rpc(ctx, &param);
+		} else {
+			ret = res.a0;
+			break;
+		}
+	}
+
+	/*
+	 * We're done with our thread in secure world, if there's any
+	 * thread waiters wake up one.
+	 */
+	optee_cq_wait_final(&optee->call_queue, &w);
+
+	return ret;
+}
+
+static struct tee_shm *get_msg_arg(struct tee_context *ctx, size_t num_params,
+				   struct optee_msg_arg **msg_arg,
+				   phys_addr_t *msg_parg)
+{
+	int rc;
+	struct tee_shm *shm;
+	struct optee_msg_arg *ma;
+
+	shm = tee_shm_alloc(ctx, OPTEE_MSG_GET_ARG_SIZE(num_params),
+			    TEE_SHM_MAPPED);
+	if (IS_ERR(shm))
+		return shm;
+
+	ma = tee_shm_get_va(shm, 0);
+	if (IS_ERR(ma)) {
+		rc = PTR_ERR(ma);
+		goto out;
+	}
+
+	rc = tee_shm_get_pa(shm, 0, msg_parg);
+	if (rc)
+		goto out;
+
+	memset(ma, 0, OPTEE_MSG_GET_ARG_SIZE(num_params));
+	ma->num_params = num_params;
+	*msg_arg = ma;
+out:
+	if (rc) {
+		tee_shm_free(shm);
+		return ERR_PTR(rc);
+	}
+
+	return shm;
+}
+
+int optee_open_session(struct tee_context *ctx,
+		       struct tee_ioctl_open_session_arg *arg,
+		       struct tee_param *param)
+{
+	struct optee_context_data *ctxdata = ctx->data;
+	int rc;
+	struct tee_shm *shm;
+	struct optee_msg_arg *msg_arg;
+	phys_addr_t msg_parg;
+	struct optee_session *sess = NULL;
+
+	/* +2 for the meta parameters added below */
+	shm = get_msg_arg(ctx, arg->num_params + 2, &msg_arg, &msg_parg);
+	if (IS_ERR(shm))
+		return PTR_ERR(shm);
+
+	msg_arg->cmd = OPTEE_MSG_CMD_OPEN_SESSION;
+	msg_arg->cancel_id = arg->cancel_id;
+
+	/*
+	 * Initialize and add the meta parameters needed when opening a
+	 * session.
+	 */
+	msg_arg->params[0].attr = OPTEE_MSG_ATTR_TYPE_VALUE_INPUT |
+				  OPTEE_MSG_ATTR_META;
+	msg_arg->params[1].attr = OPTEE_MSG_ATTR_TYPE_VALUE_INPUT |
+				  OPTEE_MSG_ATTR_META;
+	memcpy(&msg_arg->params[0].u.value, arg->uuid, sizeof(arg->uuid));
+	memcpy(&msg_arg->params[1].u.value, arg->uuid, sizeof(arg->clnt_uuid));
+	msg_arg->params[1].u.value.c = arg->clnt_login;
+
+	rc = optee_to_msg_param(msg_arg->params + 2, arg->num_params, param);
+	if (rc)
+		goto out;
+
+	sess = kzalloc(sizeof(*sess), GFP_KERNEL);
+	if (!sess) {
+		rc = -ENOMEM;
+		goto out;
+	}
+
+	if (optee_do_call_with_arg(ctx, msg_parg)) {
+		msg_arg->ret = TEEC_ERROR_COMMUNICATION;
+		msg_arg->ret_origin = TEEC_ORIGIN_COMMS;
+	}
+
+	if (msg_arg->ret == TEEC_SUCCESS) {
+		/* A new session has been created, add it to the list. */
+		sess->session_id = msg_arg->session;
+		mutex_lock(&ctxdata->mutex);
+		list_add(&sess->list_node, &ctxdata->sess_list);
+		mutex_unlock(&ctxdata->mutex);
+	} else {
+		kfree(sess);
+	}
+
+	if (optee_from_msg_param(param, arg->num_params, msg_arg->params + 2)) {
+		arg->ret = TEEC_ERROR_COMMUNICATION;
+		arg->ret_origin = TEEC_ORIGIN_COMMS;
+		/* Close session again to avoid leakage */
+		optee_close_session(ctx, msg_arg->session);
+	} else {
+		arg->session = msg_arg->session;
+		arg->ret = msg_arg->ret;
+		arg->ret_origin = msg_arg->ret_origin;
+	}
+out:
+	tee_shm_free(shm);
+
+	return rc;
+}
+
+int optee_close_session(struct tee_context *ctx, u32 session)
+{
+	struct optee_context_data *ctxdata = ctx->data;
+	struct tee_shm *shm;
+	struct optee_msg_arg *msg_arg;
+	phys_addr_t msg_parg;
+	struct optee_session *sess;
+
+	/* Check that the session is valid and remove it from the list */
+	mutex_lock(&ctxdata->mutex);
+	sess = find_session(ctxdata, session);
+	if (sess)
+		list_del(&sess->list_node);
+	mutex_unlock(&ctxdata->mutex);
+	if (!sess)
+		return -EINVAL;
+	kfree(sess);
+
+	shm = get_msg_arg(ctx, 0, &msg_arg, &msg_parg);
+	if (IS_ERR(shm))
+		return PTR_ERR(shm);
+
+	msg_arg->cmd = OPTEE_MSG_CMD_CLOSE_SESSION;
+	msg_arg->session = session;
+	optee_do_call_with_arg(ctx, msg_parg);
+
+	tee_shm_free(shm);
+	return 0;
+}
+
+int optee_invoke_func(struct tee_context *ctx, struct tee_ioctl_invoke_arg *arg,
+		      struct tee_param *param)
+{
+	struct optee_context_data *ctxdata = ctx->data;
+	struct tee_shm *shm;
+	struct optee_msg_arg *msg_arg;
+	phys_addr_t msg_parg;
+	struct optee_session *sess;
+	int rc;
+
+	/* Check that the session is valid */
+	mutex_lock(&ctxdata->mutex);
+	sess = find_session(ctxdata, arg->session);
+	mutex_unlock(&ctxdata->mutex);
+	if (!sess)
+		return -EINVAL;
+
+	shm = get_msg_arg(ctx, arg->num_params, &msg_arg, &msg_parg);
+	if (IS_ERR(shm))
+		return PTR_ERR(shm);
+	msg_arg->cmd = OPTEE_MSG_CMD_INVOKE_COMMAND;
+	msg_arg->func = arg->func;
+	msg_arg->session = arg->session;
+	msg_arg->cancel_id = arg->cancel_id;
+
+	rc = optee_to_msg_param(msg_arg->params, arg->num_params, param);
+	if (rc)
+		goto out;
+
+	if (optee_do_call_with_arg(ctx, msg_parg)) {
+		msg_arg->ret = TEEC_ERROR_COMMUNICATION;
+		msg_arg->ret_origin = TEEC_ORIGIN_COMMS;
+	}
+
+	if (optee_from_msg_param(param, arg->num_params, msg_arg->params)) {
+		msg_arg->ret = TEEC_ERROR_COMMUNICATION;
+		msg_arg->ret_origin = TEEC_ORIGIN_COMMS;
+	}
+
+	arg->ret = msg_arg->ret;
+	arg->ret_origin = msg_arg->ret_origin;
+out:
+	tee_shm_free(shm);
+	return rc;
+}
+
+int optee_cancel_req(struct tee_context *ctx, u32 cancel_id, u32 session)
+{
+	struct optee_context_data *ctxdata = ctx->data;
+	struct tee_shm *shm;
+	struct optee_msg_arg *msg_arg;
+	phys_addr_t msg_parg;
+	struct optee_session *sess;
+
+	/* Check that the session is valid */
+	mutex_lock(&ctxdata->mutex);
+	sess = find_session(ctxdata, session);
+	mutex_unlock(&ctxdata->mutex);
+	if (!sess)
+		return -EINVAL;
+
+	shm = get_msg_arg(ctx, 0, &msg_arg, &msg_parg);
+	if (IS_ERR(shm))
+		return PTR_ERR(shm);
+
+	msg_arg->cmd = OPTEE_MSG_CMD_CANCEL;
+	msg_arg->session = session;
+	msg_arg->cancel_id = cancel_id;
+	optee_do_call_with_arg(ctx, msg_parg);
+
+	tee_shm_free(shm);
+	return 0;
+}
+
+/**
+ * optee_enable_shm_cache() - Enables caching of some shared memory allocation
+ *			      in OP-TEE
+ * @optee:	main service struct
+ */
+void optee_enable_shm_cache(struct optee *optee)
+{
+	struct optee_call_waiter w;
+
+	/* We need to retry until secure world isn't busy. */
+	optee_cq_wait_init(&optee->call_queue, &w);
+	while (true) {
+		struct arm_smccc_res res;
+
+		optee->invoke_fn(OPTEE_SMC_ENABLE_SHM_CACHE, 0, 0, 0, 0, 0, 0,
+				 0, &res);
+		if (res.a0 == OPTEE_SMC_RETURN_OK)
+			break;
+		optee_cq_wait_for_completion(&optee->call_queue, &w);
+	}
+	optee_cq_wait_final(&optee->call_queue, &w);
+}
+
+/**
+ * optee_disable_shm_cache() - Disables caching of some shared memory allocation
+ *			      in OP-TEE
+ * @optee:	main service struct
+ */
+void optee_disable_shm_cache(struct optee *optee)
+{
+	struct optee_call_waiter w;
+
+	/* We need to retry until secure world isn't busy. */
+	optee_cq_wait_init(&optee->call_queue, &w);
+	while (true) {
+		union {
+			struct arm_smccc_res smccc;
+			struct optee_smc_disable_shm_cache_result result;
+		} res;
+
+		optee->invoke_fn(OPTEE_SMC_DISABLE_SHM_CACHE, 0, 0, 0, 0, 0, 0,
+				 0, &res.smccc);
+		if (res.result.status == OPTEE_SMC_RETURN_ENOTAVAIL)
+			break; /* All shm's freed */
+		if (res.result.status == OPTEE_SMC_RETURN_OK) {
+			struct tee_shm *shm;
+
+			shm = reg_pair_to_ptr(res.result.shm_upper32,
+					      res.result.shm_lower32);
+			tee_shm_free(shm);
+		} else {
+			optee_cq_wait_for_completion(&optee->call_queue, &w);
+		}
+	}
+	optee_cq_wait_final(&optee->call_queue, &w);
+}
diff --git a/drivers/tee/optee/core.c b/drivers/tee/optee/core.c
new file mode 100644
index 000000000000..58169e519422
--- /dev/null
+++ b/drivers/tee/optee/core.c
@@ -0,0 +1,622 @@
+/*
+ * Copyright (c) 2015, Linaro Limited
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/arm-smccc.h>
+#include <linux/errno.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/tee_drv.h>
+#include <linux/types.h>
+#include <linux/uaccess.h>
+#include "optee_private.h"
+#include "optee_smc.h"
+
+#define DRIVER_NAME "optee"
+
+#define OPTEE_SHM_NUM_PRIV_PAGES	1
+
+/**
+ * optee_from_msg_param() - convert from OPTEE_MSG parameters to
+ *			    struct tee_param
+ * @params:	subsystem internal parameter representation
+ * @num_params:	number of elements in the parameter arrays
+ * @msg_params:	OPTEE_MSG parameters
+ * Returns 0 on success or <0 on failure
+ */
+int optee_from_msg_param(struct tee_param *params, size_t num_params,
+			 const struct optee_msg_param *msg_params)
+{
+	int rc;
+	size_t n;
+	struct tee_shm *shm;
+	phys_addr_t pa;
+
+	for (n = 0; n < num_params; n++) {
+		struct tee_param *p = params + n;
+		const struct optee_msg_param *mp = msg_params + n;
+		u32 attr = mp->attr & OPTEE_MSG_ATTR_TYPE_MASK;
+
+		switch (attr) {
+		case OPTEE_MSG_ATTR_TYPE_NONE:
+			p->attr = TEE_IOCTL_PARAM_ATTR_TYPE_NONE;
+			memset(&p->u, 0, sizeof(p->u));
+			break;
+		case OPTEE_MSG_ATTR_TYPE_VALUE_INPUT:
+		case OPTEE_MSG_ATTR_TYPE_VALUE_OUTPUT:
+		case OPTEE_MSG_ATTR_TYPE_VALUE_INOUT:
+			p->attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT +
+				  attr - OPTEE_MSG_ATTR_TYPE_VALUE_INPUT;
+			p->u.value.a = mp->u.value.a;
+			p->u.value.b = mp->u.value.b;
+			p->u.value.c = mp->u.value.c;
+			break;
+		case OPTEE_MSG_ATTR_TYPE_TMEM_INPUT:
+		case OPTEE_MSG_ATTR_TYPE_TMEM_OUTPUT:
+		case OPTEE_MSG_ATTR_TYPE_TMEM_INOUT:
+			p->attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT +
+				  attr - OPTEE_MSG_ATTR_TYPE_TMEM_INPUT;
+			p->u.memref.size = mp->u.tmem.size;
+			shm = (struct tee_shm *)(unsigned long)
+				mp->u.tmem.shm_ref;
+			if (!shm) {
+				p->u.memref.shm_offs = 0;
+				p->u.memref.shm = NULL;
+				break;
+			}
+			rc = tee_shm_get_pa(shm, 0, &pa);
+			if (rc)
+				return rc;
+			p->u.memref.shm_offs = mp->u.tmem.buf_ptr - pa;
+			p->u.memref.shm = shm;
+
+			/* Check that the memref is covered by the shm object */
+			if (p->u.memref.size) {
+				size_t o = p->u.memref.shm_offs +
+					   p->u.memref.size - 1;
+
+				rc = tee_shm_get_pa(shm, o, NULL);
+				if (rc)
+					return rc;
+			}
+			break;
+		default:
+			return -EINVAL;
+		}
+	}
+	return 0;
+}
+
+/**
+ * optee_to_msg_param() - convert from struct tee_params to OPTEE_MSG parameters
+ * @msg_params:	OPTEE_MSG parameters
+ * @num_params:	number of elements in the parameter arrays
+ * @params:	subsystem itnernal parameter representation
+ * Returns 0 on success or <0 on failure
+ */
+int optee_to_msg_param(struct optee_msg_param *msg_params, size_t num_params,
+		       const struct tee_param *params)
+{
+	int rc;
+	size_t n;
+	phys_addr_t pa;
+
+	for (n = 0; n < num_params; n++) {
+		const struct tee_param *p = params + n;
+		struct optee_msg_param *mp = msg_params + n;
+
+		switch (p->attr) {
+		case TEE_IOCTL_PARAM_ATTR_TYPE_NONE:
+			mp->attr = TEE_IOCTL_PARAM_ATTR_TYPE_NONE;
+			memset(&mp->u, 0, sizeof(mp->u));
+			break;
+		case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT:
+		case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT:
+		case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT:
+			mp->attr = OPTEE_MSG_ATTR_TYPE_VALUE_INPUT + p->attr -
+				   TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT;
+			mp->u.value.a = p->u.value.a;
+			mp->u.value.b = p->u.value.b;
+			mp->u.value.c = p->u.value.c;
+			break;
+		case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT:
+		case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
+		case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
+			mp->attr = OPTEE_MSG_ATTR_TYPE_TMEM_INPUT +
+				   p->attr -
+				   TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT;
+			mp->u.tmem.shm_ref = (unsigned long)p->u.memref.shm;
+			mp->u.tmem.size = p->u.memref.size;
+			if (!p->u.memref.shm) {
+				mp->u.tmem.buf_ptr = 0;
+				break;
+			}
+			rc = tee_shm_get_pa(p->u.memref.shm,
+					    p->u.memref.shm_offs, &pa);
+			if (rc)
+				return rc;
+			mp->u.tmem.buf_ptr = pa;
+			mp->attr |= OPTEE_MSG_ATTR_CACHE_PREDEFINED <<
+					OPTEE_MSG_ATTR_CACHE_SHIFT;
+			break;
+		default:
+			return -EINVAL;
+		}
+	}
+	return 0;
+}
+
+static void optee_get_version(struct tee_device *teedev,
+			      struct tee_ioctl_version_data *vers)
+{
+	struct tee_ioctl_version_data v = {
+		.impl_id = TEE_IMPL_ID_OPTEE,
+		.impl_caps = TEE_OPTEE_CAP_TZ,
+		.gen_caps = TEE_GEN_CAP_GP,
+	};
+	*vers = v;
+}
+
+static int optee_open(struct tee_context *ctx)
+{
+	struct optee_context_data *ctxdata;
+	struct tee_device *teedev = ctx->teedev;
+	struct optee *optee = tee_get_drvdata(teedev);
+
+	ctxdata = kzalloc(sizeof(*ctxdata), GFP_KERNEL);
+	if (!ctxdata)
+		return -ENOMEM;
+
+	if (teedev == optee->supp_teedev) {
+		bool busy = true;
+
+		mutex_lock(&optee->supp.ctx_mutex);
+		if (!optee->supp.ctx) {
+			busy = false;
+			optee->supp.ctx = ctx;
+		}
+		mutex_unlock(&optee->supp.ctx_mutex);
+		if (busy) {
+			kfree(ctxdata);
+			return -EBUSY;
+		}
+	}
+
+	mutex_init(&ctxdata->mutex);
+	INIT_LIST_HEAD(&ctxdata->sess_list);
+
+	ctx->data = ctxdata;
+	return 0;
+}
+
+static void optee_release(struct tee_context *ctx)
+{
+	struct optee_context_data *ctxdata = ctx->data;
+	struct tee_device *teedev = ctx->teedev;
+	struct optee *optee = tee_get_drvdata(teedev);
+	struct tee_shm *shm;
+	struct optee_msg_arg *arg = NULL;
+	phys_addr_t parg;
+	struct optee_session *sess;
+	struct optee_session *sess_tmp;
+
+	if (!ctxdata)
+		return;
+
+	shm = tee_shm_alloc(ctx, sizeof(struct optee_msg_arg), TEE_SHM_MAPPED);
+	if (!IS_ERR(shm)) {
+		arg = tee_shm_get_va(shm, 0);
+		/*
+		 * If va2pa fails for some reason, we can't call
+		 * optee_close_session(), only free the memory. Secure OS
+		 * will leak sessions and finally refuse more sessions, but
+		 * we will at least let normal world reclaim its memory.
+		 */
+		if (!IS_ERR(arg))
+			tee_shm_va2pa(shm, arg, &parg);
+	}
+
+	list_for_each_entry_safe(sess, sess_tmp, &ctxdata->sess_list,
+				 list_node) {
+		list_del(&sess->list_node);
+		if (!IS_ERR_OR_NULL(arg)) {
+			memset(arg, 0, sizeof(*arg));
+			arg->cmd = OPTEE_MSG_CMD_CLOSE_SESSION;
+			arg->session = sess->session_id;
+			optee_do_call_with_arg(ctx, parg);
+		}
+		kfree(sess);
+	}
+	kfree(ctxdata);
+
+	if (!IS_ERR(shm))
+		tee_shm_free(shm);
+
+	ctx->data = NULL;
+
+	if (teedev == optee->supp_teedev) {
+		mutex_lock(&optee->supp.ctx_mutex);
+		optee->supp.ctx = NULL;
+		mutex_unlock(&optee->supp.ctx_mutex);
+	}
+}
+
+static struct tee_driver_ops optee_ops = {
+	.get_version = optee_get_version,
+	.open = optee_open,
+	.release = optee_release,
+	.open_session = optee_open_session,
+	.close_session = optee_close_session,
+	.invoke_func = optee_invoke_func,
+	.cancel_req = optee_cancel_req,
+};
+
+static struct tee_desc optee_desc = {
+	.name = DRIVER_NAME "-clnt",
+	.ops = &optee_ops,
+	.owner = THIS_MODULE,
+};
+
+static struct tee_driver_ops optee_supp_ops = {
+	.get_version = optee_get_version,
+	.open = optee_open,
+	.release = optee_release,
+	.supp_recv = optee_supp_recv,
+	.supp_send = optee_supp_send,
+};
+
+static struct tee_desc optee_supp_desc = {
+	.name = DRIVER_NAME "-supp",
+	.ops = &optee_supp_ops,
+	.owner = THIS_MODULE,
+	.flags = TEE_DESC_PRIVILEGED,
+};
+
+static bool optee_msg_api_uid_is_optee_api(optee_invoke_fn *invoke_fn)
+{
+	struct arm_smccc_res res;
+
+	invoke_fn(OPTEE_SMC_CALLS_UID, 0, 0, 0, 0, 0, 0, 0, &res);
+
+	if (res.a0 == OPTEE_MSG_UID_0 && res.a1 == OPTEE_MSG_UID_1 &&
+	    res.a2 == OPTEE_MSG_UID_2 && res.a3 == OPTEE_MSG_UID_3)
+		return true;
+	return false;
+}
+
+static bool optee_msg_api_revision_is_compatible(optee_invoke_fn *invoke_fn)
+{
+	union {
+		struct arm_smccc_res smccc;
+		struct optee_smc_calls_revision_result result;
+	} res;
+
+	invoke_fn(OPTEE_SMC_CALLS_REVISION, 0, 0, 0, 0, 0, 0, 0, &res.smccc);
+
+	if (res.result.major == OPTEE_MSG_REVISION_MAJOR &&
+	    (int)res.result.minor >= OPTEE_MSG_REVISION_MINOR)
+		return true;
+	return false;
+}
+
+static bool optee_msg_exchange_capabilities(optee_invoke_fn *invoke_fn,
+					    u32 *sec_caps)
+{
+	union {
+		struct arm_smccc_res smccc;
+		struct optee_smc_exchange_capabilities_result result;
+	} res;
+	u32 a1 = 0;
+
+	/*
+	 * TODO This isn't enough to tell if it's UP system (from kernel
+	 * point of view) or not, is_smp() returns the the information
+	 * needed, but can't be called directly from here.
+	 */
+	if (!IS_ENABLED(CONFIG_SMP) || nr_cpu_ids == 1)
+		a1 |= OPTEE_SMC_NSEC_CAP_UNIPROCESSOR;
+
+	invoke_fn(OPTEE_SMC_EXCHANGE_CAPABILITIES, a1, 0, 0, 0, 0, 0, 0,
+		  &res.smccc);
+
+	if (res.result.status != OPTEE_SMC_RETURN_OK)
+		return false;
+
+	*sec_caps = res.result.capabilities;
+	return true;
+}
+
+static struct tee_shm_pool *
+optee_config_shm_memremap(optee_invoke_fn *invoke_fn, void **memremaped_shm)
+{
+	union {
+		struct arm_smccc_res smccc;
+		struct optee_smc_get_shm_config_result result;
+	} res;
+	struct tee_shm_pool *pool;
+	unsigned long vaddr;
+	phys_addr_t paddr;
+	size_t size;
+	phys_addr_t begin;
+	phys_addr_t end;
+	void *va;
+	struct tee_shm_pool_mem_info priv_info;
+	struct tee_shm_pool_mem_info dmabuf_info;
+
+	invoke_fn(OPTEE_SMC_GET_SHM_CONFIG, 0, 0, 0, 0, 0, 0, 0, &res.smccc);
+	if (res.result.status != OPTEE_SMC_RETURN_OK) {
+		pr_info("shm service not available\n");
+		return ERR_PTR(-ENOENT);
+	}
+
+	if (res.result.settings != OPTEE_SMC_SHM_CACHED) {
+		pr_err("only normal cached shared memory supported\n");
+		return ERR_PTR(-EINVAL);
+	}
+
+	begin = roundup(res.result.start, PAGE_SIZE);
+	end = rounddown(res.result.start + res.result.size, PAGE_SIZE);
+	paddr = begin;
+	size = end - begin;
+
+	if (size < 2 * OPTEE_SHM_NUM_PRIV_PAGES * PAGE_SIZE) {
+		pr_err("too small shared memory area\n");
+		return ERR_PTR(-EINVAL);
+	}
+
+	va = memremap(paddr, size, MEMREMAP_WB);
+	if (!va) {
+		pr_err("shared memory ioremap failed\n");
+		return ERR_PTR(-EINVAL);
+	}
+	vaddr = (unsigned long)va;
+
+	priv_info.vaddr = vaddr;
+	priv_info.paddr = paddr;
+	priv_info.size = OPTEE_SHM_NUM_PRIV_PAGES * PAGE_SIZE;
+	dmabuf_info.vaddr = vaddr + OPTEE_SHM_NUM_PRIV_PAGES * PAGE_SIZE;
+	dmabuf_info.paddr = paddr + OPTEE_SHM_NUM_PRIV_PAGES * PAGE_SIZE;
+	dmabuf_info.size = size - OPTEE_SHM_NUM_PRIV_PAGES * PAGE_SIZE;
+
+	pool = tee_shm_pool_alloc_res_mem(&priv_info, &dmabuf_info);
+	if (IS_ERR(pool)) {
+		memunmap(va);
+		goto out;
+	}
+
+	*memremaped_shm = va;
+out:
+	return pool;
+}
+
+/* Simple wrapper functions to be able to use a function pointer */
+static void optee_smccc_smc(unsigned long a0, unsigned long a1,
+			    unsigned long a2, unsigned long a3,
+			    unsigned long a4, unsigned long a5,
+			    unsigned long a6, unsigned long a7,
+			    struct arm_smccc_res *res)
+{
+	arm_smccc_smc(a0, a1, a2, a3, a4, a5, a6, a7, res);
+}
+
+static void optee_smccc_hvc(unsigned long a0, unsigned long a1,
+			    unsigned long a2, unsigned long a3,
+			    unsigned long a4, unsigned long a5,
+			    unsigned long a6, unsigned long a7,
+			    struct arm_smccc_res *res)
+{
+	arm_smccc_hvc(a0, a1, a2, a3, a4, a5, a6, a7, res);
+}
+
+static optee_invoke_fn *get_invoke_func(struct device_node *np)
+{
+	const char *method;
+
+	pr_info("probing for conduit method from DT.\n");
+
+	if (of_property_read_string(np, "method", &method)) {
+		pr_warn("missing \"method\" property\n");
+		return ERR_PTR(-ENXIO);
+	}
+
+	if (!strcmp("hvc", method))
+		return optee_smccc_hvc;
+	else if (!strcmp("smc", method))
+		return optee_smccc_smc;
+
+	pr_warn("invalid \"method\" property: %s\n", method);
+	return ERR_PTR(-EINVAL);
+}
+
+static struct optee *optee_probe(struct device_node *np)
+{
+	optee_invoke_fn *invoke_fn;
+	struct tee_shm_pool *pool;
+	struct optee *optee = NULL;
+	void *memremaped_shm = NULL;
+	struct tee_device *teedev;
+	u32 sec_caps;