Merge tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Don't destroy user event fields when removal fails

   User event fields are destroyed before the event is removed from
   visibility. But that can fail leaving the still visible event with no
   fields. Move the destroying of the fields to after the event is
   successfully removed from visibility.

 - Initialize function graph state is fork before calling
   copy_exec_state()

   For non-CLONE_VM forks, copy_exec_state() allocates a new
   task_exec_state. If that allocation fails, ftrace_graph_exit_task()
   will free the tasks ret_stack pointer. Since that pointer is still
   using the parent's ret_stack, it mistakenly frees the parent's
   pointer too.

   Call ftrace_graph_init() on the task first which will NULL out the
   new tasks's ret_stack and if the copy fails, it will not free
   anything.

 - Remove FGRAPH_MAX_INDEX

   The macro FGRAPH_MAX_INDEX was added but never used. Remove it.

 - Save ent_size in function graph printing of nested functions

   The function graph tracer needs to look at the next event to see if
   the next event is the return of the current function entry. If it is,
   it prints a single line:

	ktime_get();

   Otherwise it prints it like a nested function:

	tick_nohz_irq_exit() {
	    ktime_get();
	    kcpustat_irq_exit();
	}

   In order to look at the next event, it must save the current event so
   that it has the information to print from it. It saves the event in
   the iterator descriptor called "ent". What it doesn't save is the
   ent_size of the event which is now used to know if the function graph
   arguments are to be printed. The peek doesn't save the size so the
   size used happens to be that of the size of the last event that was
   seen.

   Save the entry event size in the iterator descriptor so that the
   correct size is used.

 - Fix several errors with freeing data in the histogram code

   The histogram code had a lot of leaked or or incorrect accounting
   when failures happen. Correct them.

 - Fix histogram regression of .percent and .graph modifiers

   Up until 6.3 histogram values could have "percent" or "graph"
   modifiers that changed how they were printed. But a change that added
   restricting histograms values from being strings, stack traces and
   other modifiers inadvertently prevented them from using the percent
   and graph modifiers, which were legal use cases for values.

   Put back the percent and graph modifiers.

 - Fix various typos in the comments

 - Set the trace_clock before initializing a histogram with clock
   argument

   The histogram API allows the user to specific which trace clock to
   use via a "clock=" string. The histogram is set up first before the
   clock is checked. If the passed in clock is not valid, it exits
   without fully fixing up the histogram leaving it on the list and a
   use-after-free can trigger.

   Update the clock argument first and if it fails then exit gracefully
   before the histogram trigger is placed on any lists.

 - Restore :mod: trailer after parsing in ftrace_set_clr_event

   The function ftrace_set_clr_event() modifies the parse string and
   needs to put it back to what was passed in. It searches for ":mod:"
   via a strsep() but fails to put back the first ':' in the string.

   Add back the ':' in the passed in string.

 - Take trace_array reference when opening a tracer options file

   The options files are dynamically created and some tracers add their
   own options. When a tracer adds their own list of options, the
   trace_array holding them has an array to hold the list of options for
   each tracer. This array increases in size via a krealloc(), and the
   new entry gets a newly allocated array to hold the options of the new
   tracer being added.

   The element in each entry of the tracer's option array holds a
   pointer back to the trace_array, a pointer to the tracer it is
   associated to, a pointer to the flags of the option.

   The issue is that these arrays are freed when the trace_array is
   freed when its instance it represents is removed from the instances
   directory. There's a race that an open of one of these options files
   can happen when the instance is being removed.

   Add a new helper function to be called by the open function of the
   options file to iterate all existing trace_arrays under a lock and
   find the one that has the given option element in one of it's tracer
   arrays. If found, then update the associated trace_array's reference
   counter to keep it from being freed. If not found, have the open call
   return -ENODEV.

 - Disable interrupts when acquiring the lock in rb_wake_up_waiters()

   The function rb_wake_up_waiters() assumes it will be called in
   interrupt context and does not disable irqs when taking
   cpu_buffer->reader_lock, which can be called in hard interrupt
   context. The issue is in PREEMPT_RT, this function is called in
   thread context leaving this lock open to a deadlock.

   Take the lock with interrupts disabled.

 - Use rcu_assign_pointer() for tmp_ops filter hash

   The tmp_ops used in update_ftrace_direct_mod() assigns its
   filter_hash field directly, but that field is annotated as __rcu and
   sparse complains. Assign it with rcu_assign_pointer()

 - Fix use-after-free in enable_trigger_private_data_free()

   The trace_event_call is accessed through the event_trigger_data's
   trace_event_file pointer to put the trace_event_call on freeing. The
   issue is that the trace_event_file data may have been freed already
   causing a use-after-free. Add a field to the event_trigger_data that
   points directly to the trace_event_call so that it can decrement its
   reference directly without needing to go through the
   trace_event_file.

 - Fix accounting of buffer data remote headers

   trace_buffer_desc_size() and trace_remote_alloc_buffer() undercount
   the number of pages is needed for the asked for size as it doesn't
   take into account the meta data on each page. Add a helper function
   to do the calculation properly and use that in these functions.

 - Catch nr_page_va overflow in ring_buffer_desc sizing

   The number of pages per remote ring buffer is capped by
   ring_buffer_desc::nr_page_va (32 bits). A buffer_size large enough to
   overflow that field would silently allocate a descriptor smaller than
   what was asked for.

 - Do not resize the subbuf order if any per_cpu buffer is disabled

   The mmapping of ring buffers disables resizing the subbuffers, but it
   is done per-cpu whereas the subbuf size change is done for all the
   per_cpu buffers under the buffer->mutex. It could change the size of
   some while the mapping is happening on others. Have the resize of the
   subbuf order check all the per_cpu buffers under the lock to see if
   any of them is disabled before starting and causing an inconsistency
   between buffers that are being mapped.

* tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (25 commits)
  ring-buffer: Check resize_disabled before publishing the new subbuf order
  tracing/remotes: Catch nr_page_va overflow in ring_buffer_desc sizing
  tracing/remotes: Account for ring buffer page header in size calculation
  tracing: Don't dereference trace_event_file in deferred trigger free
  ftrace: Use rcu_assign_pointer() for tmp_ops filter hash
  ring-buffer: Acquire the lock with irqsave in rb_wake_up_waiters()
  tracing: Take trace_array reference when opening a tracer options file
  tracing: Fix ring_buffer_read_page_size() kernel-doc
  tracing: Restore :mod: trailer after parsing in ftrace_set_clr_event()
  tracing: Fix memory corruption from a "STACKTRACE" histogram key
  tracing: Fix memory corruption from the histogram stacktrace modifier
  tracing: Undo the registration when enabling the histogram trigger fails
  tracing: Take the reference before publishing the named histogram trigger
  tracing: Set the trace clock before registering the histogram trigger
  tracing: Fix typo "preceeded" in comment
  tracing: Fix typo "availabe" in comment
  tracing: Let histogram values keep the percent and graph modifiers
  tracing: Keep the entry count when the histogram stats allocation fails
  tracing: Free histogram the field rejected for a bad modifier
  tracing: Free histogram the var ref when its initialization fails
  ...

4 files changed, 586 insertions, 0 deletions

diff --git a/drivers/tee/tstee/Kconfig b/drivers/tee/tstee/Kconfig
new file mode 100644
index 000000000..d32f91d47
--- /dev/null
+++ b/drivers/tee/tstee/Kconfig
@@ -0,0 +1,11 @@
+# SPDX-License-Identifier: GPL-2.0-only
+config ARM_TSTEE
+	tristate "Arm Trusted Services TEE driver"
+	depends on ARM_FFA_TRANSPORT
+	default n
+	help
+	  The Trusted Services project provides a framework for developing and
+	  deploying device Root of Trust services in FF-A Secure Partitions.
+	  This driver provides an interface to make Trusted Services Secure
+	  Partitions accessible for user space clients, since the FF-A driver
+	  doesn't implement a user space interface directly.
diff --git a/drivers/tee/tstee/Makefile b/drivers/tee/tstee/Makefile
new file mode 100644
index 000000000..5227020eb
--- /dev/null
+++ b/drivers/tee/tstee/Makefile
@@ -0,0 +1,3 @@
+# SPDX-License-Identifier: GPL-2.0-only
+arm-tstee-objs := core.o
+obj-$(CONFIG_ARM_TSTEE) = arm-tstee.o
diff --git a/drivers/tee/tstee/core.c b/drivers/tee/tstee/core.c
new file mode 100644
index 000000000..79ae5d161
--- /dev/null
+++ b/drivers/tee/tstee/core.c
@@ -0,0 +1,480 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2023, Arm Limited
+ */
+
+#include <linux/arm_ffa.h>
+#include <linux/err.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/limits.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/scatterlist.h>
+#include <linux/slab.h>
+#include <linux/tee_core.h>
+#include <linux/types.h>
+#include <linux/uuid.h>
+#include <linux/xarray.h>
+#include "tstee_private.h"
+
+#define FFA_DIRECT_REQ_ARG_NUM 5
+#define FFA_INVALID_MEM_HANDLE U64_MAX
+
+static void arg_list_to_ffa_data(const u32 *args,
+				 struct ffa_send_direct_data *data)
+{
+	data->data0 = args[0];
+	data->data1 = args[1];
+	data->data2 = args[2];
+	data->data3 = args[3];
+	data->data4 = args[4];
+}
+
+static void arg_list_from_ffa_data(const struct ffa_send_direct_data *data,
+				   u32 *args)
+{
+	args[0] = lower_32_bits(data->data0);
+	args[1] = lower_32_bits(data->data1);
+	args[2] = lower_32_bits(data->data2);
+	args[3] = lower_32_bits(data->data3);
+	args[4] = lower_32_bits(data->data4);
+}
+
+static void tstee_get_version(struct tee_device *teedev,
+			      struct tee_ioctl_version_data *vers)
+{
+	struct tstee *tstee = tee_get_drvdata(teedev);
+	struct tee_ioctl_version_data v = {
+		.impl_id = TEE_IMPL_ID_TSTEE,
+		/* FF-A endpoint ID only uses the lower 16 bits */
+		.impl_caps = lower_16_bits(tstee->ffa_dev->vm_id),
+		.gen_caps = 0,
+	};
+
+	*vers = v;
+}
+
+static int tstee_open(struct tee_context *ctx)
+{
+	struct ts_context_data *ctxdata;
+
+	ctxdata = kzalloc_obj(*ctxdata);
+	if (!ctxdata)
+		return -ENOMEM;
+
+	xa_init_flags(&ctxdata->sess_list, XA_FLAGS_ALLOC);
+
+	ctx->data = ctxdata;
+
+	return 0;
+}
+
+static void tstee_release(struct tee_context *ctx)
+{
+	struct ts_context_data *ctxdata = ctx->data;
+	struct ts_session *sess;
+	unsigned long idx;
+
+	if (!ctxdata)
+		return;
+
+	xa_for_each(&ctxdata->sess_list, idx, sess) {
+		xa_erase(&ctxdata->sess_list, idx);
+		kfree(sess);
+	}
+
+	xa_destroy(&ctxdata->sess_list);
+
+	kfree(ctxdata);
+	ctx->data = NULL;
+}
+
+static int tstee_open_session(struct tee_context *ctx,
+			      struct tee_ioctl_open_session_arg *arg,
+			      struct tee_param *param __always_unused)
+{
+	struct tstee *tstee = tee_get_drvdata(ctx->teedev);
+	struct ffa_device *ffa_dev = tstee->ffa_dev;
+	struct ts_context_data *ctxdata = ctx->data;
+	struct ffa_send_direct_data ffa_data;
+	struct ts_session *sess = NULL;
+	u32 ffa_args[FFA_DIRECT_REQ_ARG_NUM] = {};
+	u32 sess_id;
+	int rc;
+
+	ffa_args[TS_RPC_CTRL_REG] =
+		TS_RPC_CTRL_PACK_IFACE_OPCODE(TS_RPC_MGMT_IFACE_ID,
+					      TS_RPC_OP_SERVICE_INFO);
+
+	memcpy(ffa_args + TS_RPC_SERVICE_INFO_UUID0, arg->uuid, UUID_SIZE);
+
+	arg_list_to_ffa_data(ffa_args, &ffa_data);
+	rc = ffa_dev->ops->msg_ops->sync_send_receive(ffa_dev, &ffa_data);
+	if (rc)
+		return rc;
+
+	arg_list_from_ffa_data(&ffa_data, ffa_args);
+
+	if (ffa_args[TS_RPC_SERVICE_INFO_RPC_STATUS] != TS_RPC_OK)
+		return -ENODEV;
+
+	if (ffa_args[TS_RPC_SERVICE_INFO_IFACE] > U8_MAX)
+		return -EINVAL;
+
+	sess = kzalloc_obj(*sess);
+	if (!sess)
+		return -ENOMEM;
+
+	sess->iface_id = ffa_args[TS_RPC_SERVICE_INFO_IFACE];
+
+	rc = xa_alloc(&ctxdata->sess_list, &sess_id, sess, xa_limit_32b,
+		      GFP_KERNEL);
+	if (rc) {
+		kfree(sess);
+		return rc;
+	}
+
+	arg->session = sess_id;
+	arg->ret = 0;
+
+	return 0;
+}
+
+static int tstee_close_session(struct tee_context *ctx, u32 session)
+{
+	struct ts_context_data *ctxdata = ctx->data;
+	struct ts_session *sess;
+
+	/* Calls xa_lock() internally */
+	sess = xa_erase(&ctxdata->sess_list, session);
+	if (!sess)
+		return -EINVAL;
+
+	kfree(sess);
+
+	return 0;
+}
+
+static int tstee_invoke_func(struct tee_context *ctx,
+			     struct tee_ioctl_invoke_arg *arg,
+			     struct tee_param *param)
+{
+	struct tstee *tstee = tee_get_drvdata(ctx->teedev);
+	struct ffa_device *ffa_dev = tstee->ffa_dev;
+	struct ts_context_data *ctxdata = ctx->data;
+	struct ffa_send_direct_data ffa_data;
+	struct tee_shm *shm = NULL;
+	struct ts_session *sess;
+	u32 req_len, ffa_args[FFA_DIRECT_REQ_ARG_NUM] = {};
+	int shm_id, rc;
+	u8 iface_id;
+	u64 handle;
+	u16 opcode;
+
+	xa_lock(&ctxdata->sess_list);
+	sess = xa_load(&ctxdata->sess_list, arg->session);
+
+	/*
+	 * Do this while holding the lock to make sure that the session wasn't
+	 * closed meanwhile
+	 */
+	if (sess)
+		iface_id = sess->iface_id;
+
+	xa_unlock(&ctxdata->sess_list);
+	if (!sess)
+		return -EINVAL;
+
+	opcode = lower_16_bits(arg->func);
+	shm_id = lower_32_bits(param[0].u.value.a);
+	req_len = lower_32_bits(param[0].u.value.b);
+
+	if (shm_id != 0) {
+		shm = tee_shm_get_from_id(ctx, shm_id);
+		if (IS_ERR(shm))
+			return PTR_ERR(shm);
+
+		if (shm->size < req_len) {
+			dev_err(&ffa_dev->dev,
+				"request doesn't fit into shared memory buffer\n");
+			rc = -EINVAL;
+			goto out;
+		}
+
+		handle = shm->sec_world_id;
+	} else {
+		handle = FFA_INVALID_MEM_HANDLE;
+	}
+
+	ffa_args[TS_RPC_CTRL_REG] = TS_RPC_CTRL_PACK_IFACE_OPCODE(iface_id,
+								  opcode);
+	ffa_args[TS_RPC_SERVICE_MEM_HANDLE_LSW] = lower_32_bits(handle);
+	ffa_args[TS_RPC_SERVICE_MEM_HANDLE_MSW] = upper_32_bits(handle);
+	ffa_args[TS_RPC_SERVICE_REQ_LEN] = req_len;
+	ffa_args[TS_RPC_SERVICE_CLIENT_ID] = 0;
+
+	arg_list_to_ffa_data(ffa_args, &ffa_data);
+	rc = ffa_dev->ops->msg_ops->sync_send_receive(ffa_dev, &ffa_data);
+	if (rc)
+		goto out;
+
+	arg_list_from_ffa_data(&ffa_data, ffa_args);
+
+	if (ffa_args[TS_RPC_SERVICE_RPC_STATUS] != TS_RPC_OK) {
+		dev_err(&ffa_dev->dev, "invoke_func rpc status: %d\n",
+			ffa_args[TS_RPC_SERVICE_RPC_STATUS]);
+		rc = -EINVAL;
+		goto out;
+	}
+
+	arg->ret = ffa_args[TS_RPC_SERVICE_STATUS];
+	if (shm && shm->size >= ffa_args[TS_RPC_SERVICE_RESP_LEN])
+		param[0].u.value.a = ffa_args[TS_RPC_SERVICE_RESP_LEN];
+
+out:
+	if (shm)
+		tee_shm_put(shm);
+
+	return rc;
+}
+
+static int tstee_shm_register(struct tee_context *ctx, struct tee_shm *shm,
+			      struct page **pages, size_t num_pages,
+			      unsigned long start __always_unused)
+{
+	struct tstee *tstee = tee_get_drvdata(ctx->teedev);
+	struct ffa_device *ffa_dev = tstee->ffa_dev;
+	struct ffa_mem_region_attributes mem_attr = {
+		.receiver = tstee->ffa_dev->vm_id,
+		.attrs = FFA_MEM_RW,
+		.flag = 0,
+	};
+	struct ffa_mem_ops_args mem_args = {
+		.attrs = &mem_attr,
+		.use_txbuf = true,
+		.nattrs = 1,
+		.flags = 0,
+	};
+	struct ffa_send_direct_data ffa_data;
+	struct sg_table sgt;
+	u32 ffa_args[FFA_DIRECT_REQ_ARG_NUM] = {};
+	int rc;
+
+	rc = sg_alloc_table_from_pages(&sgt, pages, num_pages, 0,
+				       num_pages * PAGE_SIZE, GFP_KERNEL);
+	if (rc)
+		return rc;
+
+	mem_args.sg = sgt.sgl;
+	rc = ffa_dev->ops->mem_ops->memory_share(&mem_args);
+	sg_free_table(&sgt);
+	if (rc)
+		return rc;
+
+	shm->sec_world_id = mem_args.g_handle;
+
+	ffa_args[TS_RPC_CTRL_REG] =
+			TS_RPC_CTRL_PACK_IFACE_OPCODE(TS_RPC_MGMT_IFACE_ID,
+						      TS_RPC_OP_RETRIEVE_MEM);
+	ffa_args[TS_RPC_RETRIEVE_MEM_HANDLE_LSW] =
+			lower_32_bits(shm->sec_world_id);
+	ffa_args[TS_RPC_RETRIEVE_MEM_HANDLE_MSW] =
+			upper_32_bits(shm->sec_world_id);
+	ffa_args[TS_RPC_RETRIEVE_MEM_TAG_LSW] = 0;
+	ffa_args[TS_RPC_RETRIEVE_MEM_TAG_MSW] = 0;
+
+	arg_list_to_ffa_data(ffa_args, &ffa_data);
+	rc = ffa_dev->ops->msg_ops->sync_send_receive(ffa_dev, &ffa_data);
+	if (rc) {
+		(void)ffa_dev->ops->mem_ops->memory_reclaim(shm->sec_world_id,
+							    0);
+		return rc;
+	}
+
+	arg_list_from_ffa_data(&ffa_data, ffa_args);
+
+	if (ffa_args[TS_RPC_RETRIEVE_MEM_RPC_STATUS] != TS_RPC_OK) {
+		dev_err(&ffa_dev->dev, "shm_register rpc status: %d\n",
+			ffa_args[TS_RPC_RETRIEVE_MEM_RPC_STATUS]);
+		ffa_dev->ops->mem_ops->memory_reclaim(shm->sec_world_id, 0);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int tstee_shm_unregister(struct tee_context *ctx, struct tee_shm *shm)
+{
+	struct tstee *tstee = tee_get_drvdata(ctx->teedev);
+	struct ffa_device *ffa_dev = tstee->ffa_dev;
+	struct ffa_send_direct_data ffa_data;
+	u32 ffa_args[FFA_DIRECT_REQ_ARG_NUM] = {};
+	int rc;
+
+	ffa_args[TS_RPC_CTRL_REG] =
+			TS_RPC_CTRL_PACK_IFACE_OPCODE(TS_RPC_MGMT_IFACE_ID,
+						      TS_RPC_OP_RELINQ_MEM);
+	ffa_args[TS_RPC_RELINQ_MEM_HANDLE_LSW] =
+			lower_32_bits(shm->sec_world_id);
+	ffa_args[TS_RPC_RELINQ_MEM_HANDLE_MSW] =
+			upper_32_bits(shm->sec_world_id);
+
+	arg_list_to_ffa_data(ffa_args, &ffa_data);
+	rc = ffa_dev->ops->msg_ops->sync_send_receive(ffa_dev, &ffa_data);
+	if (rc)
+		return rc;
+	arg_list_from_ffa_data(&ffa_data, ffa_args);
+
+	if (ffa_args[TS_RPC_RELINQ_MEM_RPC_STATUS] != TS_RPC_OK) {
+		dev_err(&ffa_dev->dev, "shm_unregister rpc status: %d\n",
+			ffa_args[TS_RPC_RELINQ_MEM_RPC_STATUS]);
+		return -EINVAL;
+	}
+
+	rc = ffa_dev->ops->mem_ops->memory_reclaim(shm->sec_world_id, 0);
+
+	return rc;
+}
+
+static const struct tee_driver_ops tstee_ops = {
+	.get_version = tstee_get_version,
+	.open = tstee_open,
+	.release = tstee_release,
+	.open_session = tstee_open_session,
+	.close_session = tstee_close_session,
+	.invoke_func = tstee_invoke_func,
+};
+
+static const struct tee_desc tstee_desc = {
+	.name = "tstee-clnt",
+	.ops = &tstee_ops,
+	.owner = THIS_MODULE,
+};
+
+static int pool_op_alloc(struct tee_shm_pool *pool, struct tee_shm *shm,
+			 size_t size, size_t align)
+{
+	return tee_dyn_shm_alloc_helper(shm, size, align, tstee_shm_register);
+}
+
+static void pool_op_free(struct tee_shm_pool *pool, struct tee_shm *shm)
+{
+	tee_dyn_shm_free_helper(shm, tstee_shm_unregister);
+}
+
+static void pool_op_destroy_pool(struct tee_shm_pool *pool)
+{
+	kfree(pool);
+}
+
+static const struct tee_shm_pool_ops pool_ops = {
+	.alloc = pool_op_alloc,
+	.free = pool_op_free,
+	.destroy_pool = pool_op_destroy_pool,
+};
+
+static struct tee_shm_pool *tstee_create_shm_pool(void)
+{
+	struct tee_shm_pool *pool = kzalloc_obj(*pool);
+
+	if (!pool)
+		return ERR_PTR(-ENOMEM);
+
+	pool->ops = &pool_ops;
+
+	return pool;
+}
+
+static bool tstee_check_rpc_compatible(struct ffa_device *ffa_dev)
+{
+	struct ffa_send_direct_data ffa_data;
+	u32 ffa_args[FFA_DIRECT_REQ_ARG_NUM] = {};
+
+	ffa_args[TS_RPC_CTRL_REG] =
+			TS_RPC_CTRL_PACK_IFACE_OPCODE(TS_RPC_MGMT_IFACE_ID,
+						      TS_RPC_OP_GET_VERSION);
+
+	arg_list_to_ffa_data(ffa_args, &ffa_data);
+	if (ffa_dev->ops->msg_ops->sync_send_receive(ffa_dev, &ffa_data))
+		return false;
+
+	arg_list_from_ffa_data(&ffa_data, ffa_args);
+
+	return ffa_args[TS_RPC_GET_VERSION_RESP] == TS_RPC_PROTOCOL_VERSION;
+}
+
+static int tstee_probe(struct ffa_device *ffa_dev)
+{
+	struct tstee *tstee;
+	int rc;
+
+	ffa_dev->ops->msg_ops->mode_32bit_set(ffa_dev);
+
+	if (!tstee_check_rpc_compatible(ffa_dev))
+		return -EINVAL;
+
+	tstee = kzalloc_obj(*tstee);
+	if (!tstee)
+		return -ENOMEM;
+
+	tstee->ffa_dev = ffa_dev;
+
+	tstee->pool = tstee_create_shm_pool();
+	if (IS_ERR(tstee->pool)) {
+		rc = PTR_ERR(tstee->pool);
+		tstee->pool = NULL;
+		goto err_free_tstee;
+	}
+
+	tstee->teedev = tee_device_alloc(&tstee_desc, NULL, tstee->pool, tstee);
+	if (IS_ERR(tstee->teedev)) {
+		rc = PTR_ERR(tstee->teedev);
+		tstee->teedev = NULL;
+		goto err_free_pool;
+	}
+
+	rc = tee_device_register(tstee->teedev);
+	if (rc)
+		goto err_unreg_teedev;
+
+	ffa_dev_set_drvdata(ffa_dev, tstee);
+
+	return 0;
+
+err_unreg_teedev:
+	tee_device_unregister(tstee->teedev);
+err_free_pool:
+	tee_shm_pool_free(tstee->pool);
+err_free_tstee:
+	kfree(tstee);
+	return rc;
+}
+
+static void tstee_remove(struct ffa_device *ffa_dev)
+{
+	struct tstee *tstee = ffa_dev->dev.driver_data;
+
+	tee_device_unregister(tstee->teedev);
+	tee_shm_pool_free(tstee->pool);
+	kfree(tstee);
+}
+
+static const struct ffa_device_id tstee_device_ids[] = {
+	/* TS RPC protocol UUID: bdcd76d7-825e-4751-963b-86d4f84943ac */
+	{ TS_RPC_UUID },
+	{}
+};
+
+static struct ffa_driver tstee_driver = {
+	.name = "arm_tstee",
+	.probe = tstee_probe,
+	.remove = tstee_remove,
+	.id_table = tstee_device_ids,
+};
+
+module_ffa_driver(tstee_driver);
+
+MODULE_AUTHOR("Balint Dobszay <balint.dobszay@arm.com>");
+MODULE_DESCRIPTION("Arm Trusted Services TEE driver");
+MODULE_LICENSE("GPL");
diff --git a/drivers/tee/tstee/tstee_private.h b/drivers/tee/tstee/tstee_private.h
new file mode 100644
index 000000000..8e58725b5
--- /dev/null
+++ b/drivers/tee/tstee/tstee_private.h
@@ -0,0 +1,92 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (c) 2023, Arm Limited
+ */
+
+#ifndef TSTEE_PRIVATE_H
+#define TSTEE_PRIVATE_H
+
+#include <linux/arm_ffa.h>
+#include <linux/bitops.h>
+#include <linux/tee_core.h>
+#include <linux/types.h>
+#include <linux/uuid.h>
+#include <linux/xarray.h>
+
+/*
+ * The description of the ABI implemented in this file is available at
+ * https://trusted-services.readthedocs.io/en/v1.0.0/developer/service-access-protocols.html#abi
+ */
+
+/* UUID of this protocol */
+#define TS_RPC_UUID UUID_INIT(0xbdcd76d7, 0x825e, 0x4751, \
+			      0x96, 0x3b, 0x86, 0xd4, 0xf8, 0x49, 0x43, 0xac)
+
+/* Protocol version*/
+#define TS_RPC_PROTOCOL_VERSION		(1)
+
+/* Status codes */
+#define TS_RPC_OK			(0)
+
+/* RPC control register */
+#define TS_RPC_CTRL_REG			(0)
+#define OPCODE_MASK			GENMASK(15, 0)
+#define IFACE_ID_MASK			GENMASK(23, 16)
+#define TS_RPC_CTRL_OPCODE(x)		((u16)(FIELD_GET(OPCODE_MASK, (x))))
+#define TS_RPC_CTRL_IFACE_ID(x)		((u8)(FIELD_GET(IFACE_ID_MASK, (x))))
+#define TS_RPC_CTRL_PACK_IFACE_OPCODE(i, o)	\
+	(FIELD_PREP(IFACE_ID_MASK, (i)) | FIELD_PREP(OPCODE_MASK, (o)))
+#define TS_RPC_CTRL_SAP_RC		BIT(30)
+#define TS_RPC_CTRL_SAP_ERR		BIT(31)
+
+/* Interface ID for RPC management operations */
+#define TS_RPC_MGMT_IFACE_ID		(0xff)
+
+/* Management calls */
+#define TS_RPC_OP_GET_VERSION		(0x0000)
+#define TS_RPC_GET_VERSION_RESP		(1)
+
+#define TS_RPC_OP_RETRIEVE_MEM		(0x0001)
+#define TS_RPC_RETRIEVE_MEM_HANDLE_LSW	(1)
+#define TS_RPC_RETRIEVE_MEM_HANDLE_MSW	(2)
+#define TS_RPC_RETRIEVE_MEM_TAG_LSW	(3)
+#define TS_RPC_RETRIEVE_MEM_TAG_MSW	(4)
+#define TS_RPC_RETRIEVE_MEM_RPC_STATUS	(1)
+
+#define TS_RPC_OP_RELINQ_MEM		(0x0002)
+#define TS_RPC_RELINQ_MEM_HANDLE_LSW	(1)
+#define TS_RPC_RELINQ_MEM_HANDLE_MSW	(2)
+#define TS_RPC_RELINQ_MEM_RPC_STATUS	(1)
+
+#define TS_RPC_OP_SERVICE_INFO		(0x0003)
+#define TS_RPC_SERVICE_INFO_UUID0	(1)
+#define TS_RPC_SERVICE_INFO_UUID1	(2)
+#define TS_RPC_SERVICE_INFO_UUID2	(3)
+#define TS_RPC_SERVICE_INFO_UUID3	(4)
+#define TS_RPC_SERVICE_INFO_RPC_STATUS	(1)
+#define TS_RPC_SERVICE_INFO_IFACE	(2)
+
+/* Service call */
+#define TS_RPC_SERVICE_MEM_HANDLE_LSW	(1)
+#define TS_RPC_SERVICE_MEM_HANDLE_MSW	(2)
+#define TS_RPC_SERVICE_REQ_LEN		(3)
+#define TS_RPC_SERVICE_CLIENT_ID	(4)
+#define TS_RPC_SERVICE_RPC_STATUS	(1)
+#define TS_RPC_SERVICE_STATUS		(2)
+#define TS_RPC_SERVICE_RESP_LEN		(3)
+
+struct tstee {
+	struct ffa_device *ffa_dev;
+	struct tee_device *teedev;
+	struct tee_shm_pool *pool;
+};
+
+struct ts_session {
+	u8 iface_id;
+};
+
+struct ts_context_data {
+	struct xarray sess_list;
+};
+
+#endif /* TSTEE_PRIVATE_H */