[PATCH v20 5/6] remoteproc: Add TEE support

Arnaud Pouliquen posted 6 patches 1 month, 3 weeks ago
[PATCH v20 5/6] remoteproc: Add TEE support
Posted by Arnaud Pouliquen 1 month, 3 weeks ago
Add a remoteproc TEE (Trusted Execution Environment) driver that will be
probed by the TEE bus. If the associated Trusted application is supported
on the secure part, this driver offers a client interface to load firmware
by the secure part.
This firmware could be authenticated by the secure trusted application.

A specificity of the implementation is that the firmware has to be
authenticated and optionally decrypted to access the resource table.

Consequently, the boot sequence is:

1) rproc_parse_fw --> rproc_tee_parse_fw
   remoteproc TEE:
   - Requests the TEE application to authenticate and load the firmware
     in the remote processor memories.
   - Requests the TEE application for the address of the resource table.
   - Creates a copy of the resource table stored in rproc->cached_table.

2) rproc_load_segments --> rproc_tee_load_fw
   remoteproc TEE:
   - Requests the TEE application to load the firmware. Nothing is done
     at the TEE application as the firmware is already loaded.
   - In case of recovery, the TEE application has to reload the firmware.

3) rproc_tee_get_loaded_rsc_table
   remoteproc TEE requests the TEE application for the address of the
   resource table.

4) rproc_start --> rproc_tee_start
   - Requests the TEE application to start the remote processor.

The shutdown sequence is:

5) rproc_stop --> rproc_tee_stop
   - Requests the TEE application to stop the remote processor.

6) rproc_tee_release_fw
   This function is used to request the TEE application to perform actions
   to return to the initial state on stop or on error during the boot
   sequence.

Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@foss.st.com>
---
Version 20 updates:
- rework probe. the remoteproc-tee now probe the remoteproc devices
  defined in device tree as child.
  - creation of rproc-service-80a4c275-0a47-4905-8285-1486a9771a08 compatible
  - use of of_find_compatible_node() to find node in DT
  - use of of_platform_populate() to probe remoteproc devices
- remove device_link_add() as now managed by of_platform_populate)
- add "auto_boot" parameter in rproc_tee_register()
- rename TA_RPROC_FW_CMD_* TEE CMD in  TA_RPROC_CMD_* command
- use of DEFINE_MUTEX

Version 19 updates:
- rework/fix function headers
- use memremap instead of ioremap for the resource table.
- realign comments to 80 chars limit, with few exceptions for readability
- replace spinlock by mutex and and protect APIs from concurrent access
- add support of 64-bit address in rproc_tee_get_loaded_rsc_table()
- update copyright year

Version 18 updates:
Fix warning:
warning: EXPORT_SYMBOL() is used, but #include <linux/export.h> is missing
---
 drivers/remoteproc/Kconfig          |  10 +
 drivers/remoteproc/Makefile         |   1 +
 drivers/remoteproc/remoteproc_tee.c | 771 ++++++++++++++++++++++++++++
 include/linux/remoteproc_tee.h      |  89 ++++
 4 files changed, 871 insertions(+)
 create mode 100644 drivers/remoteproc/remoteproc_tee.c
 create mode 100644 include/linux/remoteproc_tee.h

diff --git a/drivers/remoteproc/Kconfig b/drivers/remoteproc/Kconfig
index 48a0d3a69ed0..75265f3f5008 100644
--- a/drivers/remoteproc/Kconfig
+++ b/drivers/remoteproc/Kconfig
@@ -23,6 +23,16 @@ config REMOTEPROC_CDEV
 
 	  It's safe to say N if you don't want to use this interface.
 
+config REMOTEPROC_TEE
+	bool "Remoteproc support by a TEE application"
+	depends on OPTEE
+	help
+	  Support a remote processor that is managed by an application running in a Trusted
+	  Execution Environment (TEE). This application is responsible for loading the remote
+	  processor firmware image and managing its lifecycle.
+
+	  It's safe to say N if the remote processor is not managed by a TEE.
+
 config IMX_REMOTEPROC
 	tristate "i.MX remoteproc support"
 	depends on ARCH_MXC
diff --git a/drivers/remoteproc/Makefile b/drivers/remoteproc/Makefile
index 1c7598b8475d..a1a5201982d4 100644
--- a/drivers/remoteproc/Makefile
+++ b/drivers/remoteproc/Makefile
@@ -11,6 +11,7 @@ remoteproc-y				+= remoteproc_sysfs.o
 remoteproc-y				+= remoteproc_virtio.o
 remoteproc-y				+= remoteproc_elf_loader.o
 obj-$(CONFIG_REMOTEPROC_CDEV)		+= remoteproc_cdev.o
+obj-$(CONFIG_REMOTEPROC_TEE)		+= remoteproc_tee.o
 obj-$(CONFIG_IMX_REMOTEPROC)		+= imx_rproc.o
 obj-$(CONFIG_IMX_DSP_REMOTEPROC)	+= imx_dsp_rproc.o
 obj-$(CONFIG_INGENIC_VPU_RPROC)		+= ingenic_rproc.o
diff --git a/drivers/remoteproc/remoteproc_tee.c b/drivers/remoteproc/remoteproc_tee.c
new file mode 100644
index 000000000000..081420c35c88
--- /dev/null
+++ b/drivers/remoteproc/remoteproc_tee.c
@@ -0,0 +1,771 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) STMicroelectronics 2025
+ * Author: Arnaud Pouliquen <arnaud.pouliquen@foss.st.com>
+ */
+
+#include <linux/firmware.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/mutex.h>
+#include <linux/remoteproc.h>
+#include <linux/remoteproc_tee.h>
+#include <linux/slab.h>
+#include <linux/tee_drv.h>
+
+#include "remoteproc_internal.h"
+
+#define MAX_TEE_PARAM_ARRAY_MEMBER	4
+
+/*
+ * Authentication and load of the firmware image in the remote processor
+ * memories by the TEE. After this step the firmware is installed in destination
+ * memories, which can then be locked to prevent access by Linux.
+ *
+ * [in]  params[0].value.a: remote processor identifier
+ * [in]  params[1].memref:  buffer containing a temporary copy of the signed
+ *			    image to load.
+ */
+#define TA_RPROC_CMD_LOAD_FW		1
+
+/*
+ * Start the remote processor by the TEE
+ *
+ * [in]  params[0].value.a: remote processor identifier
+ */
+#define TA_RPROC_CMD_START		2
+
+/*
+ * Stop the remote processor by the TEE
+ *
+ * [in]  params[0].value.a: remote processor identifier
+ */
+#define TA_RPROC_CMD_STOP		3
+
+/*
+ * Return the address of the resource table, or 0 if not found.
+ *
+ * [in]  params[0].value.a: remote processor identifier
+ * [out] params[1].value.a: 32bit LSB resource table memory address
+ * [out] params[1].value.b: 32bit MSB resource table memory address
+ * [out] params[2].value.a: 32bit LSB resource table memory size
+ * [out] params[2].value.b: 32bit MSB resource table memory size
+ */
+#define TA_RPROC_CMD_GET_RSC_TABLE	4
+
+/*
+ * Release remote processor firmware images and associated resources.
+ * This command should be used in case an error occurs between the loading of
+ * the firmware images (TA_RPROC_CMD_LOAD_FW) and the starting of the remote
+ * processor (TA_RPROC_CMD_START) or after stopping the remote processor
+ * to release associated resources (TA_RPROC_CMD_STOP).
+ *
+ * [in]  params[0].value.a: remote processor identifier
+ */
+#define TA_RPROC_CMD_RELEASE_FW		6
+
+struct rproc_tee_context {
+	struct list_head	rproc_list;
+	struct tee_context	*tee_ctx;
+	struct device		*dev;
+};
+
+/**
+ * struct rproc_tee - TEE remoteproc structure
+ * @node:       Reference in list
+ * @rproc:      Remoteproc reference
+ * @rproc_id:   remote processor identifier
+ * @session_id: TEE session identifier
+ */
+struct rproc_tee {
+	struct list_head node;
+	struct rproc *rproc;
+	u32 rproc_id;
+	u32 session_id;
+};
+
+static struct rproc_tee_context rproc_tee_ctx;
+static DEFINE_MUTEX(ctx_lock); /* Protects concurrent manipulations of the rproc_tee_ctx*/
+
+static struct rproc_tee *rproc_to_trproc(struct rproc *rproc)
+{
+	struct rproc_tee *trproc;
+
+	list_for_each_entry(trproc, &rproc_tee_ctx.rproc_list, node)
+		if (trproc->rproc == rproc)
+			return trproc;
+	return NULL;
+}
+
+static void rproc_tee_prepare_args(struct rproc_tee *trproc, int cmd,
+				   struct tee_ioctl_invoke_arg *arg,
+				   struct tee_param *param,
+				   unsigned int num_params)
+{
+	memset(arg, 0, sizeof(*arg));
+	memset(param, 0, MAX_TEE_PARAM_ARRAY_MEMBER * sizeof(*param));
+
+	arg->func = cmd;
+	arg->session = trproc->session_id;
+	arg->num_params = num_params + 1;
+
+	param[0] = (struct tee_param) {
+		.attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT,
+		.u.value.a = trproc->rproc_id,
+	};
+}
+
+/**
+ * rproc_tee_release_fw() - Release the firmware for a TEE-based remote processor
+ * @rproc: Pointer to the struct rproc representing the remote processor
+ *
+ * This function invokes the TA_RPROC_CMD_RELEASE_FW TEE client function to
+ * release the firmware. It should only be called when the remoteproc state is
+ * RPROC_OFFLINE or RPROC_DETACHED. The function requests the TEE remoteproc
+ * application to release the firmware loaded by rproc_tee_load_fw().
+ * The request is ignored if the rproc state is RPROC_DETACHED as the remote
+ * processor is still running.
+ */
+void rproc_tee_release_fw(struct rproc *rproc)
+{
+	struct tee_param param[MAX_TEE_PARAM_ARRAY_MEMBER];
+	struct rproc_tee *trproc;
+	struct tee_ioctl_invoke_arg arg;
+	int ret;
+
+	ret = mutex_lock_interruptible(&ctx_lock);
+	if (ret)
+		return;
+
+	if (!rproc_tee_ctx.dev)
+		goto out;
+
+	trproc = rproc_to_trproc(rproc);
+	if (!trproc)
+		goto out;
+
+	/*
+	 * If the remote processor state is RPROC_DETACHED, just ignore the
+	 * request, as the remote processor is still running.
+	 */
+	if (rproc->state == RPROC_DETACHED)
+		goto out;
+
+	if (rproc->state != RPROC_OFFLINE) {
+		dev_err(rproc_tee_ctx.dev, "unexpected rproc state: %d\n", rproc->state);
+		goto out;
+	}
+
+	rproc_tee_prepare_args(trproc, TA_RPROC_CMD_RELEASE_FW, &arg, param, 0);
+
+	ret = tee_client_invoke_func(rproc_tee_ctx.tee_ctx, &arg, param);
+	if (ret < 0 || arg.ret != 0) {
+		dev_err(rproc_tee_ctx.dev,
+			"TA_RPROC_CMD_RELEASE_FW invoke failed TEE err: %#x, ret:%d\n",
+			arg.ret, ret);
+	}
+
+out:
+	mutex_unlock(&ctx_lock);
+}
+EXPORT_SYMBOL_GPL(rproc_tee_release_fw);
+
+/**
+ * rproc_tee_load_fw() - Load firmware from TEE application
+ * @rproc: Pointer to the struct rproc representing the remote processor
+ * @fw: Pointer to the firmware structure containing the firmware data and size
+ *
+ * This function invokes the TA_RPROC_CMD_LOAD_FW TEE client function to load
+ * the firmware. It registers the fw->data as a shared memory region with the
+ * TEE, and request the TEE to load the firmware. This function can be called
+ * twice during the remote processor boot, a first by rproc_tee_parse_fw() to
+ * parse the resource table , and a second time by rproc_tee_load_fw().
+ * The TEE application should ignores the command if the firmware
+ * is already loaded by rproc_tee_parse_fw().
+ *
+ * Return: 0 on success, or an error code on failure
+ */
+int rproc_tee_load_fw(struct rproc *rproc, const struct firmware *fw)
+{
+	struct tee_param param[MAX_TEE_PARAM_ARRAY_MEMBER];
+	struct rproc_tee *trproc;
+	struct tee_ioctl_invoke_arg arg;
+	struct tee_shm *fw_shm;
+	int ret;
+
+	ret = mutex_lock_interruptible(&ctx_lock);
+	if (ret)
+		return ret;
+
+	if (!rproc_tee_ctx.dev) {
+		ret = -ENODEV;
+		goto out;
+	}
+
+	trproc = rproc_to_trproc(rproc);
+	if (!trproc) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	fw_shm = tee_shm_register_kernel_buf(rproc_tee_ctx.tee_ctx, (void *)fw->data, fw->size);
+	if (IS_ERR(fw_shm)) {
+		ret = PTR_ERR(fw_shm);
+		goto out;
+	}
+
+	rproc_tee_prepare_args(trproc, TA_RPROC_CMD_LOAD_FW, &arg, param, 1);
+
+	/* Provide the address of the firmware image */
+	param[1] = (struct tee_param) {
+		.attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT,
+		.u.memref = {
+			.shm = fw_shm,
+			.size = fw->size,
+			.shm_offs = 0,
+		},
+	};
+
+	ret = tee_client_invoke_func(rproc_tee_ctx.tee_ctx, &arg, param);
+	if (ret < 0 || arg.ret != 0) {
+		dev_err(rproc_tee_ctx.dev,
+			"TA_RPROC_CMD_LOAD_FW invoke failed TEE err: %#x, ret:%d\n",
+			arg.ret, ret);
+		if (!ret)
+			ret = -EIO;
+	}
+
+	tee_shm_free(fw_shm);
+
+out:
+	mutex_unlock(&ctx_lock);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(rproc_tee_load_fw);
+
+static int rproc_tee_get_loaded_rsc_table(struct rproc *rproc, phys_addr_t *rsc_pa,
+					  size_t *table_sz)
+{
+	struct tee_param param[MAX_TEE_PARAM_ARRAY_MEMBER];
+	struct rproc_tee *trproc;
+	struct tee_ioctl_invoke_arg arg;
+	int ret;
+
+	ret = mutex_lock_interruptible(&ctx_lock);
+	if (ret)
+		return ret;
+
+	if (!rproc_tee_ctx.dev) {
+		ret = -ENODEV;
+		goto out;
+	}
+
+	trproc = rproc_to_trproc(rproc);
+	if (!trproc) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	rproc_tee_prepare_args(trproc, TA_RPROC_CMD_GET_RSC_TABLE, &arg, param, 2);
+
+	param[1].attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT;
+	param[2].attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT;
+
+	ret = tee_client_invoke_func(rproc_tee_ctx.tee_ctx, &arg, param);
+	if (ret < 0 || arg.ret != 0) {
+		dev_err(rproc_tee_ctx.dev,
+			"TA_RPROC_CMD_GET_RSC_TABLE invoke failed TEE err: %#x, ret:%d\n",
+			arg.ret, ret);
+		ret = -EIO;
+		goto out;
+	}
+
+	*table_sz = param[2].u.value.a;
+	if (sizeof(phys_addr_t) == sizeof(u64))
+		*table_sz |= param[2].u.value.b << 32;
+
+	if (*table_sz) {
+		*rsc_pa = param[1].u.value.a;
+		if (sizeof(phys_addr_t) == sizeof(u64))
+			*rsc_pa |= param[1].u.value.b << 32;
+	} else {
+		*rsc_pa = 0;
+	}
+
+out:
+	mutex_unlock(&ctx_lock);
+	return ret;
+}
+
+/**
+ * rproc_tee_parse_fw() - Get the resource table from TEE application
+ * @rproc: Pointer to the struct rproc representing the remote processor
+ * @fw: Pointer to the firmware structure containing the firmware data and size
+ *
+ * This function retrieves the loaded resource table and creates a cached_table
+ * copy. Since the firmware image is signed and potentially encrypted, the
+ * firmware must be loaded first to access the loaded resource table.
+ *
+ * Return: 0 on success, or an error code on failure
+ */
+int rproc_tee_parse_fw(struct rproc *rproc, const struct firmware *fw)
+{
+	phys_addr_t rsc_table;
+	void *rsc_va;
+	size_t table_sz;
+	int ret;
+
+	if (!rproc)
+		return -EINVAL;
+
+	/* We need first to Load the firmware, to be able to get the resource table. */
+	ret = rproc_tee_load_fw(rproc, fw);
+	if (ret)
+		return ret;
+
+	ret = rproc_tee_get_loaded_rsc_table(rproc, &rsc_table, &table_sz);
+	if (ret)
+		goto release_fw;
+
+	/*
+	 * We assume here that the memory mapping is the same between the TEE
+	 * and Linux kernel contexts. Else a new TEE remoteproc service could be
+	 * needed to get a copy of the resource table.
+	 */
+	rsc_va = memremap(rsc_table, table_sz, MEMREMAP_WC);
+	if (!rsc_va) {
+		dev_err(rproc_tee_ctx.dev, "Unable to map memory region: %pa+%zx\n",
+			&rsc_table, table_sz);
+		ret = -ENOMEM;
+		goto release_fw;
+	}
+
+	/*
+	 * Create a copy of the resource table to have the same behavior as the
+	 * ELF loader. This cached table will be used by the remoteproc core
+	 * after the remoteproc stops to free resources and for crash recovery
+	 * to reapply the settings.
+	 * The cached table will be freed by the remoteproc core.
+	 */
+	rproc->cached_table = kmemdup(rsc_va, table_sz, GFP_KERNEL);
+	memunmap(rsc_va);
+
+	if (!rproc->cached_table) {
+		ret = -ENOMEM;
+		goto release_fw;
+	}
+
+	rproc->table_ptr = rproc->cached_table;
+	rproc->table_sz = table_sz;
+
+	return 0;
+
+release_fw:
+	rproc_tee_release_fw(rproc);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(rproc_tee_parse_fw);
+
+/**
+ * rproc_tee_find_loaded_rsc_table() - Find the loaded resource table loaded by
+ *				       the TEE application
+ * @rproc: Pointer to the struct rproc representing the remote processor
+ * @fw: Pointer to the firmware structure containing the firmware data and size
+ *
+ * This function retrieves the physical address and size of the resource table
+ * loaded by the TEE application.
+ *
+ * Return: pointer to the resource table if found, or NULL if not found or size
+ * is 0
+ */
+struct resource_table *rproc_tee_find_loaded_rsc_table(struct rproc *rproc,
+						       const struct firmware *fw)
+{
+	phys_addr_t rsc_table;
+	size_t table_sz;
+	int ret;
+
+	ret = rproc_tee_get_loaded_rsc_table(rproc, &rsc_table, &table_sz);
+	if (ret)
+		return NULL;
+
+	rproc->table_sz = table_sz;
+	if (!table_sz)
+		return NULL;
+
+	/*
+	 * At this step the memory area that contains the resource table should
+	 * have been registered by the remote proc platform driver and allocated
+	 * by rproc_alloc_registered_carveouts().
+	 */
+	return rproc_pa_to_va(rproc, rsc_table, table_sz, NULL);
+}
+EXPORT_SYMBOL_GPL(rproc_tee_find_loaded_rsc_table);
+
+/**
+ * rproc_tee_start() - Request the TEE application to start the remote processor
+ * @rproc: Pointer to the struct rproc representing the remote processor
+ *
+ * This function invokes the TA_RPROC_CMD_START command to start the remote
+ * processor.
+ *
+ * Return: Returns 0 on success, -EINVAL or -EIO on failure
+ */
+int rproc_tee_start(struct rproc *rproc)
+{
+	struct tee_param param[MAX_TEE_PARAM_ARRAY_MEMBER];
+	struct rproc_tee *trproc;
+	struct tee_ioctl_invoke_arg arg;
+	int ret;
+
+	ret = mutex_lock_interruptible(&ctx_lock);
+	if (ret)
+		return ret;
+
+	if (!rproc_tee_ctx.dev) {
+		ret = -ENODEV;
+		goto out;
+	}
+
+	trproc = rproc_to_trproc(rproc);
+	if (!trproc) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	rproc_tee_prepare_args(trproc, TA_RPROC_CMD_START, &arg, param, 0);
+
+	ret = tee_client_invoke_func(rproc_tee_ctx.tee_ctx, &arg, param);
+	if (ret < 0 || arg.ret != 0) {
+		dev_err(rproc_tee_ctx.dev,
+			"TA_RPROC_CMD_START invoke failed TEE err: %#x, ret:%d\n", arg.ret, ret);
+		if (!ret)
+			ret = -EIO;
+	}
+
+out:
+	mutex_unlock(&ctx_lock);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(rproc_tee_start);
+
+/**
+ * rproc_tee_stop() - Request the TEE application to start the remote processor
+ * @rproc: Pointer to the struct rproc representing the remote processor
+ *
+ * This function invokes the TA_RPROC_CMD_STOP command to stop the remote
+ * processor.
+ *
+ * Return: Returns 0 on success, -EINVAL or -EIO on failure
+ */
+int rproc_tee_stop(struct rproc *rproc)
+{
+	struct tee_param param[MAX_TEE_PARAM_ARRAY_MEMBER];
+	struct rproc_tee *trproc;
+	struct tee_ioctl_invoke_arg arg;
+	int ret;
+
+	ret = mutex_lock_interruptible(&ctx_lock);
+	if (ret)
+		return ret;
+
+	if (!rproc_tee_ctx.dev) {
+		ret = -ENODEV;
+		goto out;
+	}
+
+	trproc = rproc_to_trproc(rproc);
+	if (!trproc) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	rproc_tee_prepare_args(trproc, TA_RPROC_CMD_STOP, &arg, param, 0);
+
+	ret = tee_client_invoke_func(rproc_tee_ctx.tee_ctx, &arg, param);
+	if (ret < 0 || arg.ret != 0) {
+		dev_err(rproc_tee_ctx.dev,
+			"TA_RPROC_CMD_STOP invoke failed TEE err: %#x, ret:%d\n", arg.ret, ret);
+		if (!ret)
+			ret = -EIO;
+	}
+
+out:
+	mutex_unlock(&ctx_lock);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(rproc_tee_stop);
+
+static const struct rproc_ops rproc_tee_default_ops = {
+	.start		= rproc_tee_start,
+	.stop		= rproc_tee_stop,
+	.load		= rproc_tee_load_fw,
+	.parse_fw	= rproc_tee_parse_fw,
+	.find_loaded_rsc_table = rproc_tee_find_loaded_rsc_table,
+	.release_fw	= rproc_tee_release_fw,
+};
+
+static const struct tee_client_device_id rproc_tee_id_table[] = {
+	{UUID_INIT(0x80a4c275, 0x0a47, 0x4905, 0x82, 0x85, 0x14, 0x86, 0xa9, 0x77, 0x1a, 0x08)},
+	{ /* sentinel */ }
+};
+
+/**
+ * rproc_tee_register() - Register a remote processor controlled by the TEE application.
+ * @dev: Pointer to client rproc device
+ * @rproc: Pointer to the struct rproc representing the remote processor
+ * @rproc_id: ID of the remote processor
+ * @auto_boot: flag to indicate if remote processor should be auto-started
+ *
+ * This function registers a remote processor that will be managed by a TEE
+ * application, by opening a session with the TEE client.
+ *
+ * Return: Returns 0 on success, or an error code on failure
+ */
+int rproc_tee_register(struct device *dev, struct rproc **rproc,
+		       unsigned int rproc_id, bool auto_boot)
+{
+	struct tee_param param[MAX_TEE_PARAM_ARRAY_MEMBER];
+	struct tee_ioctl_open_session_arg sess_arg;
+	struct device_node *np = dev->of_node;
+	struct tee_client_device *tee_device;
+	struct rproc *new_rproc;
+	struct rproc_tee *trproc;
+	const char *fw_name;
+	int ret;
+
+	ret = mutex_lock_interruptible(&ctx_lock);
+	if (ret)
+		return ret;
+
+	if (!rproc_tee_ctx.dev) {
+		ret = -ENODEV;
+		goto out;
+	}
+
+	trproc = kzalloc(sizeof(*trproc), GFP_KERNEL);
+	if (!trproc) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	/* Look for an optional firmware name */
+	ret = rproc_of_parse_firmware(dev, 0, &fw_name);
+	if (ret < 0 && ret != -EINVAL)
+		goto free_tproc;
+
+	new_rproc = rproc_alloc(dev, np->name, &rproc_tee_default_ops,
+				fw_name, sizeof(*trproc));
+	if (!new_rproc) {
+		ret = -ENOMEM;
+		goto free_tproc;
+	}
+
+	tee_device = to_tee_client_device(rproc_tee_ctx.dev);
+	memset(&sess_arg, 0, sizeof(sess_arg));
+
+	memcpy(sess_arg.uuid, tee_device->id.uuid.b, TEE_IOCTL_UUID_LEN);
+
+	sess_arg.clnt_login = TEE_IOCTL_LOGIN_REE_KERNEL;
+	sess_arg.num_params = 1;
+
+	param[0] = (struct tee_param) {
+		.attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT,
+		.u.value.a = rproc_id,
+	};
+
+	ret = tee_client_open_session(rproc_tee_ctx.tee_ctx, &sess_arg, param);
+	if (ret < 0 || sess_arg.ret != 0) {
+		dev_err(dev, "tee_client_open_session failed, err: %#x\n", sess_arg.ret);
+		ret = -EINVAL;
+		goto free_rproc;
+	}
+
+	trproc->rproc_id = rproc_id;
+	trproc->session_id = sess_arg.session;
+	new_rproc->auto_boot = auto_boot;
+
+	ret = rproc_add(new_rproc);
+	if (ret)
+		goto close_tee;
+
+	trproc->rproc = new_rproc;
+	*rproc = new_rproc;
+
+	list_add_tail(&trproc->node, &rproc_tee_ctx.rproc_list);
+
+	mutex_unlock(&ctx_lock);
+
+	return 0;
+
+close_tee:
+	if (tee_client_close_session(rproc_tee_ctx.tee_ctx, trproc->session_id))
+		dev_err(rproc_tee_ctx.dev, "tee_client_close_session failed\n");
+free_rproc:
+	rproc_free(new_rproc);
+free_tproc:
+	kfree(trproc);
+out:
+	mutex_unlock(&ctx_lock);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(rproc_tee_register);
+
+/**
+ * rproc_tee_unregister - Unregister a remote processor controlled by the TEE
+ *                        application.
+ * @dev: Pointer to client rproc device
+ * @rproc: Pointer to the struct rproc representing the remote processor
+ *
+ * This function unregisters a remote processor previously registered by the
+ * rproc_tee_register() function.
+ *
+ * Return: Returns 0 on success, or an error code on failure
+ */
+int rproc_tee_unregister(struct device *dev, struct rproc *rproc)
+{
+	struct rproc_tee *trproc;
+	int ret;
+
+	if (!rproc_tee_ctx.dev) {
+		ret = -ENODEV;
+		return ret;
+	}
+
+	trproc = rproc_to_trproc(rproc);
+	if (!trproc) {
+		ret = -EINVAL;
+		return ret;
+	}
+
+	rproc_del(rproc);
+	rproc_free(rproc);
+
+	ret = mutex_lock_interruptible(&ctx_lock);
+	if (ret)
+		return ret;
+
+	ret = tee_client_close_session(rproc_tee_ctx.tee_ctx, trproc->session_id);
+	if (ret < 0)
+		dev_err(rproc_tee_ctx.dev, "tee_client_close_session failed, err: %#x\n", ret);
+	list_del(&trproc->node);
+	kfree(trproc);
+	mutex_unlock(&ctx_lock);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(rproc_tee_unregister);
+
+static int rproc_tee_ctx_match(struct tee_ioctl_version_data *ver, const void *data)
+{
+	/* Today we support only the OP-TEE, could be extend to other tees */
+	return (ver->impl_id == TEE_IMPL_ID_OPTEE);
+}
+
+static const struct of_device_id remoteproc_tee_of_match[] = {
+	{ .compatible = "rproc-service-80a4c275-0a47-4905-8285-1486a9771a08" },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, remoteproc_tee_of_match);
+
+static int rproc_tee_probe(struct device *dev)
+{
+	struct tee_context *tee_ctx;
+	struct device_node *np;
+	int ret;
+
+	pr_err("%s %d", __func__, __LINE__);
+	np = of_find_compatible_node(NULL, NULL,
+				     remoteproc_tee_of_match[0].compatible);
+	if (!np) {
+		dev_err(dev, "Device node not found\n");
+		return -ENODEV;
+	}
+
+	/* Open context with TEE driver */
+	tee_ctx = tee_client_open_context(NULL, rproc_tee_ctx_match, NULL, NULL);
+	if (IS_ERR(tee_ctx)) {
+		ret = PTR_ERR(tee_ctx);
+		goto put_node;
+	}
+
+	ret = mutex_lock_interruptible(&ctx_lock);
+	if (ret)
+		goto close_ctx;
+
+	rproc_tee_ctx.dev = dev;
+	rproc_tee_ctx.tee_ctx = tee_ctx;
+	INIT_LIST_HEAD(&rproc_tee_ctx.rproc_list);
+
+	mutex_unlock(&ctx_lock);
+
+	ret = device_add_of_node(dev, np);
+	if (ret)
+		goto clean_ctx;
+
+	ret = of_platform_populate(np, NULL, NULL, dev);
+	if (ret) {
+		dev_err(dev, "cannot populate node (%d)\n", ret);
+		goto clean_ctx;
+	}
+
+	return 0;
+
+clean_ctx:
+	mutex_lock(&ctx_lock);
+	rproc_tee_ctx.dev = NULL;
+	rproc_tee_ctx.tee_ctx = NULL;
+	mutex_unlock(&ctx_lock);
+
+close_ctx:
+	tee_client_close_context(tee_ctx);
+
+put_node:
+	of_node_put(np);
+	return ret;
+}
+
+static int rproc_tee_remove(struct device *dev)
+{
+	of_platform_depopulate(dev);
+
+	device_remove_of_node(dev);
+
+	mutex_lock(&ctx_lock);
+	tee_client_close_context(rproc_tee_ctx.tee_ctx);
+	rproc_tee_ctx.dev = NULL;
+	rproc_tee_ctx.tee_ctx = NULL;
+	mutex_unlock(&ctx_lock);
+
+	return 0;
+}
+
+MODULE_DEVICE_TABLE(tee, rproc_tee_id_table);
+
+static struct tee_client_driver rproc_tee_fw_driver = {
+	.id_table	= rproc_tee_id_table,
+	.driver		= {
+		.name		= KBUILD_MODNAME,
+		.bus		= &tee_bus_type,
+		.probe		= rproc_tee_probe,
+		.remove		= rproc_tee_remove,
+	},
+};
+
+static int __init rproc_tee_fw_mod_init(void)
+{
+	return driver_register(&rproc_tee_fw_driver.driver);
+}
+
+static void __exit rproc_tee_fw_mod_exit(void)
+{
+	driver_unregister(&rproc_tee_fw_driver.driver);
+}
+
+module_init(rproc_tee_fw_mod_init);
+module_exit(rproc_tee_fw_mod_exit);
+
+MODULE_DESCRIPTION("remote processor TEE module");
+MODULE_LICENSE("GPL");
diff --git a/include/linux/remoteproc_tee.h b/include/linux/remoteproc_tee.h
new file mode 100644
index 000000000000..33150cff7a5a
--- /dev/null
+++ b/include/linux/remoteproc_tee.h
@@ -0,0 +1,89 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright(c) 2025 STMicroelectronics
+ */
+
+#ifndef REMOTEPROC_TEE_H
+#define REMOTEPROC_TEE_H
+
+#include <linux/tee_drv.h>
+#include <linux/firmware.h>
+#include <linux/remoteproc.h>
+
+#if IS_ENABLED(CONFIG_REMOTEPROC_TEE)
+
+int rproc_tee_register(struct device *dev, struct rproc **rproc,
+		       unsigned int rproc_id, bool auto_boot);
+int rproc_tee_unregister(struct device *dev, struct rproc *rproc);
+int rproc_tee_parse_fw(struct rproc *rproc, const struct firmware *fw);
+int rproc_tee_load_fw(struct rproc *rproc, const struct firmware *fw);
+void rproc_tee_release_fw(struct rproc *rproc);
+struct resource_table *rproc_tee_find_loaded_rsc_table(struct rproc *rproc,
+						       const struct firmware *fw);
+int rproc_tee_start(struct rproc *rproc);
+int rproc_tee_stop(struct rproc *rproc);
+int rproc_tee_pa_to_da(struct rproc *rproc, phys_addr_t pa, size_t size, u64 *da);
+#else
+
+static inline int rproc_tee_register(struct device *dev, struct rproc **rproc,
+				     unsigned int rproc_id, bool auto_boot)
+{
+	return -ENODEV;
+}
+
+static inline int rproc_tee_parse_fw(struct rproc *rproc, const struct firmware *fw)
+{
+	/* This shouldn't be possible */
+	WARN_ON(1);
+
+	return 0;
+}
+
+static inline int rproc_tee_unregister(struct device *dev, struct rproc *rproc)
+{
+	/* This shouldn't be possible */
+	WARN_ON(1);
+
+	return 0;
+}
+
+static inline int rproc_tee_load_fw(struct rproc *rproc, const struct firmware *fw)
+{
+	/* This shouldn't be possible */
+	WARN_ON(1);
+
+	return 0;
+}
+
+static inline int rproc_tee_start(struct rproc *rproc)
+{
+	/* This shouldn't be possible */
+	WARN_ON(1);
+
+	return 0;
+}
+
+static inline int rproc_tee_stop(struct rproc *rproc)
+{
+	/* This shouldn't be possible */
+	WARN_ON(1);
+
+	return 0;
+}
+
+static inline void rproc_tee_release_fw(struct rproc *rproc)
+{
+	/* This shouldn't be possible */
+	WARN_ON(1);
+}
+
+static inline struct resource_table *
+rproc_tee_find_loaded_rsc_table(struct rproc *rproc, const struct firmware *fw)
+{
+	/* This shouldn't be possible */
+	WARN_ON(1);
+
+	return NULL;
+}
+#endif /* CONFIG_REMOTEPROC_TEE */
+#endif /* REMOTEPROC_TEE_H */
-- 
2.43.0
Re: [PATCH v20 5/6] remoteproc: Add TEE support
Posted by Sumit Garg 1 month, 1 week ago
On Wed, Dec 17, 2025 at 04:39:16PM +0100, Arnaud Pouliquen wrote:
> Add a remoteproc TEE (Trusted Execution Environment) driver that will be
> probed by the TEE bus. If the associated Trusted application is supported
> on the secure part, this driver offers a client interface to load firmware
> by the secure part.
> This firmware could be authenticated by the secure trusted application.
> 
> A specificity of the implementation is that the firmware has to be
> authenticated and optionally decrypted to access the resource table.
> 
> Consequently, the boot sequence is:
> 
> 1) rproc_parse_fw --> rproc_tee_parse_fw
>    remoteproc TEE:
>    - Requests the TEE application to authenticate and load the firmware
>      in the remote processor memories.
>    - Requests the TEE application for the address of the resource table.
>    - Creates a copy of the resource table stored in rproc->cached_table.
> 
> 2) rproc_load_segments --> rproc_tee_load_fw
>    remoteproc TEE:
>    - Requests the TEE application to load the firmware. Nothing is done
>      at the TEE application as the firmware is already loaded.
>    - In case of recovery, the TEE application has to reload the firmware.
> 
> 3) rproc_tee_get_loaded_rsc_table
>    remoteproc TEE requests the TEE application for the address of the
>    resource table.
> 
> 4) rproc_start --> rproc_tee_start
>    - Requests the TEE application to start the remote processor.
> 
> The shutdown sequence is:
> 
> 5) rproc_stop --> rproc_tee_stop
>    - Requests the TEE application to stop the remote processor.
> 
> 6) rproc_tee_release_fw
>    This function is used to request the TEE application to perform actions
>    to return to the initial state on stop or on error during the boot
>    sequence.
> 
> Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@foss.st.com>
> ---
> Version 20 updates:
> - rework probe. the remoteproc-tee now probe the remoteproc devices
>   defined in device tree as child.
>   - creation of rproc-service-80a4c275-0a47-4905-8285-1486a9771a08 compatible
>   - use of of_find_compatible_node() to find node in DT
>   - use of of_platform_populate() to probe remoteproc devices
> - remove device_link_add() as now managed by of_platform_populate)
> - add "auto_boot" parameter in rproc_tee_register()
> - rename TA_RPROC_FW_CMD_* TEE CMD in  TA_RPROC_CMD_* command
> - use of DEFINE_MUTEX
> 
> Version 19 updates:
> - rework/fix function headers
> - use memremap instead of ioremap for the resource table.
> - realign comments to 80 chars limit, with few exceptions for readability
> - replace spinlock by mutex and and protect APIs from concurrent access
> - add support of 64-bit address in rproc_tee_get_loaded_rsc_table()
> - update copyright year
> 
> Version 18 updates:
> Fix warning:
> warning: EXPORT_SYMBOL() is used, but #include <linux/export.h> is missing
> ---
>  drivers/remoteproc/Kconfig          |  10 +
>  drivers/remoteproc/Makefile         |   1 +
>  drivers/remoteproc/remoteproc_tee.c | 771 ++++++++++++++++++++++++++++
>  include/linux/remoteproc_tee.h      |  89 ++++
>  4 files changed, 871 insertions(+)
>  create mode 100644 drivers/remoteproc/remoteproc_tee.c
>  create mode 100644 include/linux/remoteproc_tee.h
> 
> diff --git a/drivers/remoteproc/Kconfig b/drivers/remoteproc/Kconfig
> index 48a0d3a69ed0..75265f3f5008 100644
> --- a/drivers/remoteproc/Kconfig
> +++ b/drivers/remoteproc/Kconfig
> @@ -23,6 +23,16 @@ config REMOTEPROC_CDEV
>  
>  	  It's safe to say N if you don't want to use this interface.
>  
> +config REMOTEPROC_TEE
> +	bool "Remoteproc support by a TEE application"
> +	depends on OPTEE
> +	help
> +	  Support a remote processor that is managed by an application running in a Trusted
> +	  Execution Environment (TEE). This application is responsible for loading the remote
> +	  processor firmware image and managing its lifecycle.
> +
> +	  It's safe to say N if the remote processor is not managed by a TEE.
> +
>  config IMX_REMOTEPROC
>  	tristate "i.MX remoteproc support"
>  	depends on ARCH_MXC
> diff --git a/drivers/remoteproc/Makefile b/drivers/remoteproc/Makefile
> index 1c7598b8475d..a1a5201982d4 100644
> --- a/drivers/remoteproc/Makefile
> +++ b/drivers/remoteproc/Makefile
> @@ -11,6 +11,7 @@ remoteproc-y				+= remoteproc_sysfs.o
>  remoteproc-y				+= remoteproc_virtio.o
>  remoteproc-y				+= remoteproc_elf_loader.o
>  obj-$(CONFIG_REMOTEPROC_CDEV)		+= remoteproc_cdev.o
> +obj-$(CONFIG_REMOTEPROC_TEE)		+= remoteproc_tee.o
>  obj-$(CONFIG_IMX_REMOTEPROC)		+= imx_rproc.o
>  obj-$(CONFIG_IMX_DSP_REMOTEPROC)	+= imx_dsp_rproc.o
>  obj-$(CONFIG_INGENIC_VPU_RPROC)		+= ingenic_rproc.o
> diff --git a/drivers/remoteproc/remoteproc_tee.c b/drivers/remoteproc/remoteproc_tee.c
> new file mode 100644
> index 000000000000..081420c35c88
> --- /dev/null
> +++ b/drivers/remoteproc/remoteproc_tee.c
> @@ -0,0 +1,771 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later
> +/*
> + * Copyright (C) STMicroelectronics 2025
> + * Author: Arnaud Pouliquen <arnaud.pouliquen@foss.st.com>
> + */
> +
> +#include <linux/firmware.h>
> +#include <linux/io.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_platform.h>
> +#include <linux/mutex.h>
> +#include <linux/remoteproc.h>
> +#include <linux/remoteproc_tee.h>
> +#include <linux/slab.h>
> +#include <linux/tee_drv.h>
> +
> +#include "remoteproc_internal.h"
> +
> +#define MAX_TEE_PARAM_ARRAY_MEMBER	4
> +
> +/*
> + * Authentication and load of the firmware image in the remote processor
> + * memories by the TEE. After this step the firmware is installed in destination
> + * memories, which can then be locked to prevent access by Linux.
> + *
> + * [in]  params[0].value.a: remote processor identifier
> + * [in]  params[1].memref:  buffer containing a temporary copy of the signed
> + *			    image to load.
> + */
> +#define TA_RPROC_CMD_LOAD_FW		1
> +
> +/*
> + * Start the remote processor by the TEE
> + *
> + * [in]  params[0].value.a: remote processor identifier
> + */
> +#define TA_RPROC_CMD_START		2
> +
> +/*
> + * Stop the remote processor by the TEE
> + *
> + * [in]  params[0].value.a: remote processor identifier
> + */
> +#define TA_RPROC_CMD_STOP		3
> +
> +/*
> + * Return the address of the resource table, or 0 if not found.
> + *
> + * [in]  params[0].value.a: remote processor identifier
> + * [out] params[1].value.a: 32bit LSB resource table memory address
> + * [out] params[1].value.b: 32bit MSB resource table memory address
> + * [out] params[2].value.a: 32bit LSB resource table memory size
> + * [out] params[2].value.b: 32bit MSB resource table memory size
> + */
> +#define TA_RPROC_CMD_GET_RSC_TABLE	4
> +
> +/*
> + * Release remote processor firmware images and associated resources.
> + * This command should be used in case an error occurs between the loading of
> + * the firmware images (TA_RPROC_CMD_LOAD_FW) and the starting of the remote
> + * processor (TA_RPROC_CMD_START) or after stopping the remote processor
> + * to release associated resources (TA_RPROC_CMD_STOP).
> + *
> + * [in]  params[0].value.a: remote processor identifier
> + */
> +#define TA_RPROC_CMD_RELEASE_FW		6
> +
> +struct rproc_tee_context {
> +	struct list_head	rproc_list;
> +	struct tee_context	*tee_ctx;
> +	struct device		*dev;
> +};
> +
> +/**
> + * struct rproc_tee - TEE remoteproc structure
> + * @node:       Reference in list
> + * @rproc:      Remoteproc reference
> + * @rproc_id:   remote processor identifier
> + * @session_id: TEE session identifier
> + */
> +struct rproc_tee {
> +	struct list_head node;
> +	struct rproc *rproc;
> +	u32 rproc_id;
> +	u32 session_id;
> +};
> +
> +static struct rproc_tee_context rproc_tee_ctx;
> +static DEFINE_MUTEX(ctx_lock); /* Protects concurrent manipulations of the rproc_tee_ctx*/
> +
> +static struct rproc_tee *rproc_to_trproc(struct rproc *rproc)
> +{
> +	struct rproc_tee *trproc;
> +
> +	list_for_each_entry(trproc, &rproc_tee_ctx.rproc_list, node)
> +		if (trproc->rproc == rproc)
> +			return trproc;
> +	return NULL;
> +}
> +
> +static void rproc_tee_prepare_args(struct rproc_tee *trproc, int cmd,
> +				   struct tee_ioctl_invoke_arg *arg,
> +				   struct tee_param *param,
> +				   unsigned int num_params)
> +{
> +	memset(arg, 0, sizeof(*arg));
> +	memset(param, 0, MAX_TEE_PARAM_ARRAY_MEMBER * sizeof(*param));
> +
> +	arg->func = cmd;
> +	arg->session = trproc->session_id;
> +	arg->num_params = num_params + 1;
> +
> +	param[0] = (struct tee_param) {
> +		.attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT,
> +		.u.value.a = trproc->rproc_id,
> +	};
> +}
> +
> +/**
> + * rproc_tee_release_fw() - Release the firmware for a TEE-based remote processor
> + * @rproc: Pointer to the struct rproc representing the remote processor
> + *
> + * This function invokes the TA_RPROC_CMD_RELEASE_FW TEE client function to
> + * release the firmware. It should only be called when the remoteproc state is
> + * RPROC_OFFLINE or RPROC_DETACHED. The function requests the TEE remoteproc
> + * application to release the firmware loaded by rproc_tee_load_fw().
> + * The request is ignored if the rproc state is RPROC_DETACHED as the remote
> + * processor is still running.
> + */
> +void rproc_tee_release_fw(struct rproc *rproc)
> +{
> +	struct tee_param param[MAX_TEE_PARAM_ARRAY_MEMBER];
> +	struct rproc_tee *trproc;
> +	struct tee_ioctl_invoke_arg arg;
> +	int ret;
> +
> +	ret = mutex_lock_interruptible(&ctx_lock);
> +	if (ret)
> +		return;
> +
> +	if (!rproc_tee_ctx.dev)
> +		goto out;
> +
> +	trproc = rproc_to_trproc(rproc);
> +	if (!trproc)
> +		goto out;
> +
> +	/*
> +	 * If the remote processor state is RPROC_DETACHED, just ignore the
> +	 * request, as the remote processor is still running.
> +	 */
> +	if (rproc->state == RPROC_DETACHED)
> +		goto out;
> +
> +	if (rproc->state != RPROC_OFFLINE) {
> +		dev_err(rproc_tee_ctx.dev, "unexpected rproc state: %d\n", rproc->state);
> +		goto out;
> +	}
> +
> +	rproc_tee_prepare_args(trproc, TA_RPROC_CMD_RELEASE_FW, &arg, param, 0);
> +
> +	ret = tee_client_invoke_func(rproc_tee_ctx.tee_ctx, &arg, param);
> +	if (ret < 0 || arg.ret != 0) {
> +		dev_err(rproc_tee_ctx.dev,
> +			"TA_RPROC_CMD_RELEASE_FW invoke failed TEE err: %#x, ret:%d\n",
> +			arg.ret, ret);
> +	}
> +
> +out:
> +	mutex_unlock(&ctx_lock);
> +}
> +EXPORT_SYMBOL_GPL(rproc_tee_release_fw);
> +
> +/**
> + * rproc_tee_load_fw() - Load firmware from TEE application
> + * @rproc: Pointer to the struct rproc representing the remote processor
> + * @fw: Pointer to the firmware structure containing the firmware data and size
> + *
> + * This function invokes the TA_RPROC_CMD_LOAD_FW TEE client function to load
> + * the firmware. It registers the fw->data as a shared memory region with the
> + * TEE, and request the TEE to load the firmware. This function can be called
> + * twice during the remote processor boot, a first by rproc_tee_parse_fw() to
> + * parse the resource table , and a second time by rproc_tee_load_fw().
> + * The TEE application should ignores the command if the firmware
> + * is already loaded by rproc_tee_parse_fw().
> + *
> + * Return: 0 on success, or an error code on failure
> + */
> +int rproc_tee_load_fw(struct rproc *rproc, const struct firmware *fw)
> +{
> +	struct tee_param param[MAX_TEE_PARAM_ARRAY_MEMBER];
> +	struct rproc_tee *trproc;
> +	struct tee_ioctl_invoke_arg arg;
> +	struct tee_shm *fw_shm;
> +	int ret;
> +
> +	ret = mutex_lock_interruptible(&ctx_lock);
> +	if (ret)
> +		return ret;
> +
> +	if (!rproc_tee_ctx.dev) {
> +		ret = -ENODEV;
> +		goto out;
> +	}
> +
> +	trproc = rproc_to_trproc(rproc);
> +	if (!trproc) {
> +		ret = -EINVAL;
> +		goto out;
> +	}
> +
> +	fw_shm = tee_shm_register_kernel_buf(rproc_tee_ctx.tee_ctx, (void *)fw->data, fw->size);
> +	if (IS_ERR(fw_shm)) {
> +		ret = PTR_ERR(fw_shm);
> +		goto out;
> +	}
> +
> +	rproc_tee_prepare_args(trproc, TA_RPROC_CMD_LOAD_FW, &arg, param, 1);
> +
> +	/* Provide the address of the firmware image */
> +	param[1] = (struct tee_param) {
> +		.attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT,
> +		.u.memref = {
> +			.shm = fw_shm,
> +			.size = fw->size,
> +			.shm_offs = 0,
> +		},
> +	};
> +
> +	ret = tee_client_invoke_func(rproc_tee_ctx.tee_ctx, &arg, param);
> +	if (ret < 0 || arg.ret != 0) {
> +		dev_err(rproc_tee_ctx.dev,
> +			"TA_RPROC_CMD_LOAD_FW invoke failed TEE err: %#x, ret:%d\n",
> +			arg.ret, ret);
> +		if (!ret)
> +			ret = -EIO;
> +	}
> +
> +	tee_shm_free(fw_shm);
> +
> +out:
> +	mutex_unlock(&ctx_lock);
> +	return ret;
> +}
> +EXPORT_SYMBOL_GPL(rproc_tee_load_fw);
> +
> +static int rproc_tee_get_loaded_rsc_table(struct rproc *rproc, phys_addr_t *rsc_pa,
> +					  size_t *table_sz)
> +{
> +	struct tee_param param[MAX_TEE_PARAM_ARRAY_MEMBER];
> +	struct rproc_tee *trproc;
> +	struct tee_ioctl_invoke_arg arg;
> +	int ret;
> +
> +	ret = mutex_lock_interruptible(&ctx_lock);
> +	if (ret)
> +		return ret;
> +
> +	if (!rproc_tee_ctx.dev) {
> +		ret = -ENODEV;
> +		goto out;
> +	}
> +
> +	trproc = rproc_to_trproc(rproc);
> +	if (!trproc) {
> +		ret = -EINVAL;
> +		goto out;
> +	}
> +
> +	rproc_tee_prepare_args(trproc, TA_RPROC_CMD_GET_RSC_TABLE, &arg, param, 2);
> +
> +	param[1].attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT;
> +	param[2].attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT;
> +
> +	ret = tee_client_invoke_func(rproc_tee_ctx.tee_ctx, &arg, param);
> +	if (ret < 0 || arg.ret != 0) {
> +		dev_err(rproc_tee_ctx.dev,
> +			"TA_RPROC_CMD_GET_RSC_TABLE invoke failed TEE err: %#x, ret:%d\n",
> +			arg.ret, ret);
> +		ret = -EIO;
> +		goto out;
> +	}
> +
> +	*table_sz = param[2].u.value.a;
> +	if (sizeof(phys_addr_t) == sizeof(u64))
> +		*table_sz |= param[2].u.value.b << 32;
> +
> +	if (*table_sz) {
> +		*rsc_pa = param[1].u.value.a;
> +		if (sizeof(phys_addr_t) == sizeof(u64))
> +			*rsc_pa |= param[1].u.value.b << 32;
> +	} else {
> +		*rsc_pa = 0;
> +	}
> +
> +out:
> +	mutex_unlock(&ctx_lock);
> +	return ret;
> +}
> +
> +/**
> + * rproc_tee_parse_fw() - Get the resource table from TEE application
> + * @rproc: Pointer to the struct rproc representing the remote processor
> + * @fw: Pointer to the firmware structure containing the firmware data and size
> + *
> + * This function retrieves the loaded resource table and creates a cached_table
> + * copy. Since the firmware image is signed and potentially encrypted, the
> + * firmware must be loaded first to access the loaded resource table.
> + *
> + * Return: 0 on success, or an error code on failure
> + */
> +int rproc_tee_parse_fw(struct rproc *rproc, const struct firmware *fw)
> +{
> +	phys_addr_t rsc_table;
> +	void *rsc_va;
> +	size_t table_sz;
> +	int ret;
> +
> +	if (!rproc)
> +		return -EINVAL;
> +
> +	/* We need first to Load the firmware, to be able to get the resource table. */
> +	ret = rproc_tee_load_fw(rproc, fw);
> +	if (ret)
> +		return ret;
> +
> +	ret = rproc_tee_get_loaded_rsc_table(rproc, &rsc_table, &table_sz);
> +	if (ret)
> +		goto release_fw;
> +
> +	/*
> +	 * We assume here that the memory mapping is the same between the TEE
> +	 * and Linux kernel contexts. Else a new TEE remoteproc service could be
> +	 * needed to get a copy of the resource table.
> +	 */
> +	rsc_va = memremap(rsc_table, table_sz, MEMREMAP_WC);
> +	if (!rsc_va) {
> +		dev_err(rproc_tee_ctx.dev, "Unable to map memory region: %pa+%zx\n",
> +			&rsc_table, table_sz);
> +		ret = -ENOMEM;
> +		goto release_fw;
> +	}
> +
> +	/*
> +	 * Create a copy of the resource table to have the same behavior as the
> +	 * ELF loader. This cached table will be used by the remoteproc core
> +	 * after the remoteproc stops to free resources and for crash recovery
> +	 * to reapply the settings.
> +	 * The cached table will be freed by the remoteproc core.
> +	 */
> +	rproc->cached_table = kmemdup(rsc_va, table_sz, GFP_KERNEL);
> +	memunmap(rsc_va);
> +
> +	if (!rproc->cached_table) {
> +		ret = -ENOMEM;
> +		goto release_fw;
> +	}
> +
> +	rproc->table_ptr = rproc->cached_table;
> +	rproc->table_sz = table_sz;
> +
> +	return 0;
> +
> +release_fw:
> +	rproc_tee_release_fw(rproc);
> +	return ret;
> +}
> +EXPORT_SYMBOL_GPL(rproc_tee_parse_fw);
> +
> +/**
> + * rproc_tee_find_loaded_rsc_table() - Find the loaded resource table loaded by
> + *				       the TEE application
> + * @rproc: Pointer to the struct rproc representing the remote processor
> + * @fw: Pointer to the firmware structure containing the firmware data and size
> + *
> + * This function retrieves the physical address and size of the resource table
> + * loaded by the TEE application.
> + *
> + * Return: pointer to the resource table if found, or NULL if not found or size
> + * is 0
> + */
> +struct resource_table *rproc_tee_find_loaded_rsc_table(struct rproc *rproc,
> +						       const struct firmware *fw)
> +{
> +	phys_addr_t rsc_table;
> +	size_t table_sz;
> +	int ret;
> +
> +	ret = rproc_tee_get_loaded_rsc_table(rproc, &rsc_table, &table_sz);
> +	if (ret)
> +		return NULL;
> +
> +	rproc->table_sz = table_sz;
> +	if (!table_sz)
> +		return NULL;
> +
> +	/*
> +	 * At this step the memory area that contains the resource table should
> +	 * have been registered by the remote proc platform driver and allocated
> +	 * by rproc_alloc_registered_carveouts().
> +	 */
> +	return rproc_pa_to_va(rproc, rsc_table, table_sz, NULL);
> +}
> +EXPORT_SYMBOL_GPL(rproc_tee_find_loaded_rsc_table);
> +
> +/**
> + * rproc_tee_start() - Request the TEE application to start the remote processor
> + * @rproc: Pointer to the struct rproc representing the remote processor
> + *
> + * This function invokes the TA_RPROC_CMD_START command to start the remote
> + * processor.
> + *
> + * Return: Returns 0 on success, -EINVAL or -EIO on failure
> + */
> +int rproc_tee_start(struct rproc *rproc)
> +{
> +	struct tee_param param[MAX_TEE_PARAM_ARRAY_MEMBER];
> +	struct rproc_tee *trproc;
> +	struct tee_ioctl_invoke_arg arg;
> +	int ret;
> +
> +	ret = mutex_lock_interruptible(&ctx_lock);
> +	if (ret)
> +		return ret;
> +
> +	if (!rproc_tee_ctx.dev) {
> +		ret = -ENODEV;
> +		goto out;
> +	}
> +
> +	trproc = rproc_to_trproc(rproc);
> +	if (!trproc) {
> +		ret = -EINVAL;
> +		goto out;
> +	}
> +
> +	rproc_tee_prepare_args(trproc, TA_RPROC_CMD_START, &arg, param, 0);
> +
> +	ret = tee_client_invoke_func(rproc_tee_ctx.tee_ctx, &arg, param);
> +	if (ret < 0 || arg.ret != 0) {
> +		dev_err(rproc_tee_ctx.dev,
> +			"TA_RPROC_CMD_START invoke failed TEE err: %#x, ret:%d\n", arg.ret, ret);
> +		if (!ret)
> +			ret = -EIO;
> +	}
> +
> +out:
> +	mutex_unlock(&ctx_lock);
> +	return ret;
> +}
> +EXPORT_SYMBOL_GPL(rproc_tee_start);
> +
> +/**
> + * rproc_tee_stop() - Request the TEE application to start the remote processor
> + * @rproc: Pointer to the struct rproc representing the remote processor
> + *
> + * This function invokes the TA_RPROC_CMD_STOP command to stop the remote
> + * processor.
> + *
> + * Return: Returns 0 on success, -EINVAL or -EIO on failure
> + */
> +int rproc_tee_stop(struct rproc *rproc)
> +{
> +	struct tee_param param[MAX_TEE_PARAM_ARRAY_MEMBER];
> +	struct rproc_tee *trproc;
> +	struct tee_ioctl_invoke_arg arg;
> +	int ret;
> +
> +	ret = mutex_lock_interruptible(&ctx_lock);
> +	if (ret)
> +		return ret;
> +
> +	if (!rproc_tee_ctx.dev) {
> +		ret = -ENODEV;
> +		goto out;
> +	}
> +
> +	trproc = rproc_to_trproc(rproc);
> +	if (!trproc) {
> +		ret = -EINVAL;
> +		goto out;
> +	}
> +
> +	rproc_tee_prepare_args(trproc, TA_RPROC_CMD_STOP, &arg, param, 0);
> +
> +	ret = tee_client_invoke_func(rproc_tee_ctx.tee_ctx, &arg, param);
> +	if (ret < 0 || arg.ret != 0) {
> +		dev_err(rproc_tee_ctx.dev,
> +			"TA_RPROC_CMD_STOP invoke failed TEE err: %#x, ret:%d\n", arg.ret, ret);
> +		if (!ret)
> +			ret = -EIO;
> +	}
> +
> +out:
> +	mutex_unlock(&ctx_lock);
> +	return ret;
> +}
> +EXPORT_SYMBOL_GPL(rproc_tee_stop);
> +
> +static const struct rproc_ops rproc_tee_default_ops = {
> +	.start		= rproc_tee_start,
> +	.stop		= rproc_tee_stop,
> +	.load		= rproc_tee_load_fw,
> +	.parse_fw	= rproc_tee_parse_fw,
> +	.find_loaded_rsc_table = rproc_tee_find_loaded_rsc_table,
> +	.release_fw	= rproc_tee_release_fw,
> +};
> +
> +static const struct tee_client_device_id rproc_tee_id_table[] = {
> +	{UUID_INIT(0x80a4c275, 0x0a47, 0x4905, 0x82, 0x85, 0x14, 0x86, 0xa9, 0x77, 0x1a, 0x08)},
> +	{ /* sentinel */ }
> +};
> +
> +/**
> + * rproc_tee_register() - Register a remote processor controlled by the TEE application.
> + * @dev: Pointer to client rproc device
> + * @rproc: Pointer to the struct rproc representing the remote processor
> + * @rproc_id: ID of the remote processor
> + * @auto_boot: flag to indicate if remote processor should be auto-started
> + *
> + * This function registers a remote processor that will be managed by a TEE
> + * application, by opening a session with the TEE client.
> + *
> + * Return: Returns 0 on success, or an error code on failure
> + */
> +int rproc_tee_register(struct device *dev, struct rproc **rproc,
> +		       unsigned int rproc_id, bool auto_boot)
> +{
> +	struct tee_param param[MAX_TEE_PARAM_ARRAY_MEMBER];
> +	struct tee_ioctl_open_session_arg sess_arg;
> +	struct device_node *np = dev->of_node;
> +	struct tee_client_device *tee_device;
> +	struct rproc *new_rproc;
> +	struct rproc_tee *trproc;
> +	const char *fw_name;
> +	int ret;
> +
> +	ret = mutex_lock_interruptible(&ctx_lock);
> +	if (ret)
> +		return ret;
> +
> +	if (!rproc_tee_ctx.dev) {
> +		ret = -ENODEV;
> +		goto out;
> +	}
> +
> +	trproc = kzalloc(sizeof(*trproc), GFP_KERNEL);
> +	if (!trproc) {
> +		ret = -ENOMEM;
> +		goto out;
> +	}
> +
> +	/* Look for an optional firmware name */
> +	ret = rproc_of_parse_firmware(dev, 0, &fw_name);
> +	if (ret < 0 && ret != -EINVAL)
> +		goto free_tproc;
> +
> +	new_rproc = rproc_alloc(dev, np->name, &rproc_tee_default_ops,
> +				fw_name, sizeof(*trproc));
> +	if (!new_rproc) {
> +		ret = -ENOMEM;
> +		goto free_tproc;
> +	}
> +
> +	tee_device = to_tee_client_device(rproc_tee_ctx.dev);
> +	memset(&sess_arg, 0, sizeof(sess_arg));
> +
> +	memcpy(sess_arg.uuid, tee_device->id.uuid.b, TEE_IOCTL_UUID_LEN);
> +
> +	sess_arg.clnt_login = TEE_IOCTL_LOGIN_REE_KERNEL;
> +	sess_arg.num_params = 1;
> +
> +	param[0] = (struct tee_param) {
> +		.attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT,
> +		.u.value.a = rproc_id,
> +	};
> +
> +	ret = tee_client_open_session(rproc_tee_ctx.tee_ctx, &sess_arg, param);
> +	if (ret < 0 || sess_arg.ret != 0) {
> +		dev_err(dev, "tee_client_open_session failed, err: %#x\n", sess_arg.ret);
> +		ret = -EINVAL;
> +		goto free_rproc;
> +	}
> +
> +	trproc->rproc_id = rproc_id;
> +	trproc->session_id = sess_arg.session;
> +	new_rproc->auto_boot = auto_boot;
> +
> +	ret = rproc_add(new_rproc);
> +	if (ret)
> +		goto close_tee;
> +
> +	trproc->rproc = new_rproc;
> +	*rproc = new_rproc;
> +
> +	list_add_tail(&trproc->node, &rproc_tee_ctx.rproc_list);
> +
> +	mutex_unlock(&ctx_lock);
> +
> +	return 0;
> +
> +close_tee:
> +	if (tee_client_close_session(rproc_tee_ctx.tee_ctx, trproc->session_id))
> +		dev_err(rproc_tee_ctx.dev, "tee_client_close_session failed\n");
> +free_rproc:
> +	rproc_free(new_rproc);
> +free_tproc:
> +	kfree(trproc);
> +out:
> +	mutex_unlock(&ctx_lock);
> +	return ret;
> +}
> +EXPORT_SYMBOL_GPL(rproc_tee_register);
> +
> +/**
> + * rproc_tee_unregister - Unregister a remote processor controlled by the TEE
> + *                        application.
> + * @dev: Pointer to client rproc device
> + * @rproc: Pointer to the struct rproc representing the remote processor
> + *
> + * This function unregisters a remote processor previously registered by the
> + * rproc_tee_register() function.
> + *
> + * Return: Returns 0 on success, or an error code on failure
> + */
> +int rproc_tee_unregister(struct device *dev, struct rproc *rproc)
> +{
> +	struct rproc_tee *trproc;
> +	int ret;
> +
> +	if (!rproc_tee_ctx.dev) {
> +		ret = -ENODEV;
> +		return ret;
> +	}
> +
> +	trproc = rproc_to_trproc(rproc);
> +	if (!trproc) {
> +		ret = -EINVAL;
> +		return ret;
> +	}
> +
> +	rproc_del(rproc);
> +	rproc_free(rproc);
> +
> +	ret = mutex_lock_interruptible(&ctx_lock);
> +	if (ret)
> +		return ret;
> +
> +	ret = tee_client_close_session(rproc_tee_ctx.tee_ctx, trproc->session_id);
> +	if (ret < 0)
> +		dev_err(rproc_tee_ctx.dev, "tee_client_close_session failed, err: %#x\n", ret);
> +	list_del(&trproc->node);
> +	kfree(trproc);
> +	mutex_unlock(&ctx_lock);
> +
> +	return ret;
> +}
> +EXPORT_SYMBOL_GPL(rproc_tee_unregister);
> +
> +static int rproc_tee_ctx_match(struct tee_ioctl_version_data *ver, const void *data)
> +{
> +	/* Today we support only the OP-TEE, could be extend to other tees */
> +	return (ver->impl_id == TEE_IMPL_ID_OPTEE);
> +}
> +
> +static const struct of_device_id remoteproc_tee_of_match[] = {
> +	{ .compatible = "rproc-service-80a4c275-0a47-4905-8285-1486a9771a08" },
> +	{ /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(of, remoteproc_tee_of_match);

You don't need to define this redundant table but instead...

> +
> +static int rproc_tee_probe(struct device *dev)
> +{
> +	struct tee_context *tee_ctx;
> +	struct device_node *np;
> +	int ret;
> +
> +	pr_err("%s %d", __func__, __LINE__);
> +	np = of_find_compatible_node(NULL, NULL,
> +				     remoteproc_tee_of_match[0].compatible);

...you can get the UUID from device being passed here. With that you
should be able to fetch device specific DT properties.

-Sumit

> +	if (!np) {
> +		dev_err(dev, "Device node not found\n");
> +		return -ENODEV;
> +	}
> +
> +	/* Open context with TEE driver */
> +	tee_ctx = tee_client_open_context(NULL, rproc_tee_ctx_match, NULL, NULL);
> +	if (IS_ERR(tee_ctx)) {
> +		ret = PTR_ERR(tee_ctx);
> +		goto put_node;
> +	}
> +
> +	ret = mutex_lock_interruptible(&ctx_lock);
> +	if (ret)
> +		goto close_ctx;
> +
> +	rproc_tee_ctx.dev = dev;
> +	rproc_tee_ctx.tee_ctx = tee_ctx;
> +	INIT_LIST_HEAD(&rproc_tee_ctx.rproc_list);
> +
> +	mutex_unlock(&ctx_lock);
> +
> +	ret = device_add_of_node(dev, np);
> +	if (ret)
> +		goto clean_ctx;
> +
> +	ret = of_platform_populate(np, NULL, NULL, dev);
> +	if (ret) {
> +		dev_err(dev, "cannot populate node (%d)\n", ret);
> +		goto clean_ctx;
> +	}
> +
> +	return 0;
> +
> +clean_ctx:
> +	mutex_lock(&ctx_lock);
> +	rproc_tee_ctx.dev = NULL;
> +	rproc_tee_ctx.tee_ctx = NULL;
> +	mutex_unlock(&ctx_lock);
> +
> +close_ctx:
> +	tee_client_close_context(tee_ctx);
> +
> +put_node:
> +	of_node_put(np);
> +	return ret;
> +}
> +
> +static int rproc_tee_remove(struct device *dev)
> +{
> +	of_platform_depopulate(dev);
> +
> +	device_remove_of_node(dev);
> +
> +	mutex_lock(&ctx_lock);
> +	tee_client_close_context(rproc_tee_ctx.tee_ctx);
> +	rproc_tee_ctx.dev = NULL;
> +	rproc_tee_ctx.tee_ctx = NULL;
> +	mutex_unlock(&ctx_lock);
> +
> +	return 0;
> +}
> +
> +MODULE_DEVICE_TABLE(tee, rproc_tee_id_table);
> +
> +static struct tee_client_driver rproc_tee_fw_driver = {
> +	.id_table	= rproc_tee_id_table,
> +	.driver		= {
> +		.name		= KBUILD_MODNAME,
> +		.bus		= &tee_bus_type,
> +		.probe		= rproc_tee_probe,
> +		.remove		= rproc_tee_remove,
> +	},
> +};
> +
> +static int __init rproc_tee_fw_mod_init(void)
> +{
> +	return driver_register(&rproc_tee_fw_driver.driver);
> +}
> +
> +static void __exit rproc_tee_fw_mod_exit(void)
> +{
> +	driver_unregister(&rproc_tee_fw_driver.driver);
> +}
> +
> +module_init(rproc_tee_fw_mod_init);
> +module_exit(rproc_tee_fw_mod_exit);
> +
> +MODULE_DESCRIPTION("remote processor TEE module");
> +MODULE_LICENSE("GPL");
> diff --git a/include/linux/remoteproc_tee.h b/include/linux/remoteproc_tee.h
> new file mode 100644
> index 000000000000..33150cff7a5a
> --- /dev/null
> +++ b/include/linux/remoteproc_tee.h
> @@ -0,0 +1,89 @@
> +/* SPDX-License-Identifier: GPL-2.0-or-later */
> +/*
> + * Copyright(c) 2025 STMicroelectronics
> + */
> +
> +#ifndef REMOTEPROC_TEE_H
> +#define REMOTEPROC_TEE_H
> +
> +#include <linux/tee_drv.h>
> +#include <linux/firmware.h>
> +#include <linux/remoteproc.h>
> +
> +#if IS_ENABLED(CONFIG_REMOTEPROC_TEE)
> +
> +int rproc_tee_register(struct device *dev, struct rproc **rproc,
> +		       unsigned int rproc_id, bool auto_boot);
> +int rproc_tee_unregister(struct device *dev, struct rproc *rproc);
> +int rproc_tee_parse_fw(struct rproc *rproc, const struct firmware *fw);
> +int rproc_tee_load_fw(struct rproc *rproc, const struct firmware *fw);
> +void rproc_tee_release_fw(struct rproc *rproc);
> +struct resource_table *rproc_tee_find_loaded_rsc_table(struct rproc *rproc,
> +						       const struct firmware *fw);
> +int rproc_tee_start(struct rproc *rproc);
> +int rproc_tee_stop(struct rproc *rproc);
> +int rproc_tee_pa_to_da(struct rproc *rproc, phys_addr_t pa, size_t size, u64 *da);
> +#else
> +
> +static inline int rproc_tee_register(struct device *dev, struct rproc **rproc,
> +				     unsigned int rproc_id, bool auto_boot)
> +{
> +	return -ENODEV;
> +}
> +
> +static inline int rproc_tee_parse_fw(struct rproc *rproc, const struct firmware *fw)
> +{
> +	/* This shouldn't be possible */
> +	WARN_ON(1);
> +
> +	return 0;
> +}
> +
> +static inline int rproc_tee_unregister(struct device *dev, struct rproc *rproc)
> +{
> +	/* This shouldn't be possible */
> +	WARN_ON(1);
> +
> +	return 0;
> +}
> +
> +static inline int rproc_tee_load_fw(struct rproc *rproc, const struct firmware *fw)
> +{
> +	/* This shouldn't be possible */
> +	WARN_ON(1);
> +
> +	return 0;
> +}
> +
> +static inline int rproc_tee_start(struct rproc *rproc)
> +{
> +	/* This shouldn't be possible */
> +	WARN_ON(1);
> +
> +	return 0;
> +}
> +
> +static inline int rproc_tee_stop(struct rproc *rproc)
> +{
> +	/* This shouldn't be possible */
> +	WARN_ON(1);
> +
> +	return 0;
> +}
> +
> +static inline void rproc_tee_release_fw(struct rproc *rproc)
> +{
> +	/* This shouldn't be possible */
> +	WARN_ON(1);
> +}
> +
> +static inline struct resource_table *
> +rproc_tee_find_loaded_rsc_table(struct rproc *rproc, const struct firmware *fw)
> +{
> +	/* This shouldn't be possible */
> +	WARN_ON(1);
> +
> +	return NULL;
> +}
> +#endif /* CONFIG_REMOTEPROC_TEE */
> +#endif /* REMOTEPROC_TEE_H */
> -- 
> 2.43.0
>
Re: [PATCH v20 5/6] remoteproc: Add TEE support
Posted by Arnaud POULIQUEN 1 month ago

On 12/29/25 06:50, Sumit Garg wrote:
> On Wed, Dec 17, 2025 at 04:39:16PM +0100, Arnaud Pouliquen wrote:
>> Add a remoteproc TEE (Trusted Execution Environment) driver that will be
>> probed by the TEE bus. If the associated Trusted application is supported
>> on the secure part, this driver offers a client interface to load firmware
>> by the secure part.
>> This firmware could be authenticated by the secure trusted application.
>>
>> A specificity of the implementation is that the firmware has to be
>> authenticated and optionally decrypted to access the resource table.
>>
>> Consequently, the boot sequence is:
>>
>> 1) rproc_parse_fw --> rproc_tee_parse_fw
>>     remoteproc TEE:
>>     - Requests the TEE application to authenticate and load the firmware
>>       in the remote processor memories.
>>     - Requests the TEE application for the address of the resource table.
>>     - Creates a copy of the resource table stored in rproc->cached_table.
>>
>> 2) rproc_load_segments --> rproc_tee_load_fw
>>     remoteproc TEE:
>>     - Requests the TEE application to load the firmware. Nothing is done
>>       at the TEE application as the firmware is already loaded.
>>     - In case of recovery, the TEE application has to reload the firmware.
>>
>> 3) rproc_tee_get_loaded_rsc_table
>>     remoteproc TEE requests the TEE application for the address of the
>>     resource table.
>>
>> 4) rproc_start --> rproc_tee_start
>>     - Requests the TEE application to start the remote processor.
>>
>> The shutdown sequence is:
>>
>> 5) rproc_stop --> rproc_tee_stop
>>     - Requests the TEE application to stop the remote processor.
>>
>> 6) rproc_tee_release_fw
>>     This function is used to request the TEE application to perform actions
>>     to return to the initial state on stop or on error during the boot
>>     sequence.
>>
>> Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@foss.st.com>
>> ---
>> Version 20 updates:
>> - rework probe. the remoteproc-tee now probe the remoteproc devices
>>    defined in device tree as child.
>>    - creation of rproc-service-80a4c275-0a47-4905-8285-1486a9771a08 compatible
>>    - use of of_find_compatible_node() to find node in DT
>>    - use of of_platform_populate() to probe remoteproc devices
>> - remove device_link_add() as now managed by of_platform_populate)
>> - add "auto_boot" parameter in rproc_tee_register()
>> - rename TA_RPROC_FW_CMD_* TEE CMD in  TA_RPROC_CMD_* command
>> - use of DEFINE_MUTEX
>>
>> Version 19 updates:
>> - rework/fix function headers
>> - use memremap instead of ioremap for the resource table.
>> - realign comments to 80 chars limit, with few exceptions for readability
>> - replace spinlock by mutex and and protect APIs from concurrent access
>> - add support of 64-bit address in rproc_tee_get_loaded_rsc_table()
>> - update copyright year
>>
>> Version 18 updates:
>> Fix warning:
>> warning: EXPORT_SYMBOL() is used, but #include <linux/export.h> is missing
>> ---
>>   drivers/remoteproc/Kconfig          |  10 +
>>   drivers/remoteproc/Makefile         |   1 +
>>   drivers/remoteproc/remoteproc_tee.c | 771 ++++++++++++++++++++++++++++
>>   include/linux/remoteproc_tee.h      |  89 ++++
>>   4 files changed, 871 insertions(+)
>>   create mode 100644 drivers/remoteproc/remoteproc_tee.c
>>   create mode 100644 include/linux/remoteproc_tee.h
>>
>> diff --git a/drivers/remoteproc/Kconfig b/drivers/remoteproc/Kconfig
>> index 48a0d3a69ed0..75265f3f5008 100644
>> --- a/drivers/remoteproc/Kconfig
>> +++ b/drivers/remoteproc/Kconfig
>> @@ -23,6 +23,16 @@ config REMOTEPROC_CDEV
>>   
>>   	  It's safe to say N if you don't want to use this interface.
>>   
>> +config REMOTEPROC_TEE
>> +	bool "Remoteproc support by a TEE application"
>> +	depends on OPTEE
>> +	help
>> +	  Support a remote processor that is managed by an application running in a Trusted
>> +	  Execution Environment (TEE). This application is responsible for loading the remote
>> +	  processor firmware image and managing its lifecycle.
>> +
>> +	  It's safe to say N if the remote processor is not managed by a TEE.
>> +
>>   config IMX_REMOTEPROC
>>   	tristate "i.MX remoteproc support"
>>   	depends on ARCH_MXC
>> diff --git a/drivers/remoteproc/Makefile b/drivers/remoteproc/Makefile
>> index 1c7598b8475d..a1a5201982d4 100644
>> --- a/drivers/remoteproc/Makefile
>> +++ b/drivers/remoteproc/Makefile
>> @@ -11,6 +11,7 @@ remoteproc-y				+= remoteproc_sysfs.o
>>   remoteproc-y				+= remoteproc_virtio.o
>>   remoteproc-y				+= remoteproc_elf_loader.o
>>   obj-$(CONFIG_REMOTEPROC_CDEV)		+= remoteproc_cdev.o
>> +obj-$(CONFIG_REMOTEPROC_TEE)		+= remoteproc_tee.o
>>   obj-$(CONFIG_IMX_REMOTEPROC)		+= imx_rproc.o
>>   obj-$(CONFIG_IMX_DSP_REMOTEPROC)	+= imx_dsp_rproc.o
>>   obj-$(CONFIG_INGENIC_VPU_RPROC)		+= ingenic_rproc.o
>> diff --git a/drivers/remoteproc/remoteproc_tee.c b/drivers/remoteproc/remoteproc_tee.c
>> new file mode 100644
>> index 000000000000..081420c35c88
>> --- /dev/null
>> +++ b/drivers/remoteproc/remoteproc_tee.c
>> @@ -0,0 +1,771 @@
>> +// SPDX-License-Identifier: GPL-2.0-or-later
>> +/*
>> + * Copyright (C) STMicroelectronics 2025
>> + * Author: Arnaud Pouliquen <arnaud.pouliquen@foss.st.com>
>> + */
>> +
>> +#include <linux/firmware.h>
>> +#include <linux/io.h>
>> +#include <linux/module.h>
>> +#include <linux/of.h>
>> +#include <linux/of_platform.h>
>> +#include <linux/mutex.h>
>> +#include <linux/remoteproc.h>
>> +#include <linux/remoteproc_tee.h>
>> +#include <linux/slab.h>
>> +#include <linux/tee_drv.h>
>> +
>> +#include "remoteproc_internal.h"
>> +
>> +#define MAX_TEE_PARAM_ARRAY_MEMBER	4
>> +
>> +/*
>> + * Authentication and load of the firmware image in the remote processor
>> + * memories by the TEE. After this step the firmware is installed in destination
>> + * memories, which can then be locked to prevent access by Linux.
>> + *
>> + * [in]  params[0].value.a: remote processor identifier
>> + * [in]  params[1].memref:  buffer containing a temporary copy of the signed
>> + *			    image to load.
>> + */
>> +#define TA_RPROC_CMD_LOAD_FW		1
>> +
>> +/*
>> + * Start the remote processor by the TEE
>> + *
>> + * [in]  params[0].value.a: remote processor identifier
>> + */
>> +#define TA_RPROC_CMD_START		2
>> +
>> +/*
>> + * Stop the remote processor by the TEE
>> + *
>> + * [in]  params[0].value.a: remote processor identifier
>> + */
>> +#define TA_RPROC_CMD_STOP		3
>> +
>> +/*
>> + * Return the address of the resource table, or 0 if not found.
>> + *
>> + * [in]  params[0].value.a: remote processor identifier
>> + * [out] params[1].value.a: 32bit LSB resource table memory address
>> + * [out] params[1].value.b: 32bit MSB resource table memory address
>> + * [out] params[2].value.a: 32bit LSB resource table memory size
>> + * [out] params[2].value.b: 32bit MSB resource table memory size
>> + */
>> +#define TA_RPROC_CMD_GET_RSC_TABLE	4
>> +
>> +/*
>> + * Release remote processor firmware images and associated resources.
>> + * This command should be used in case an error occurs between the loading of
>> + * the firmware images (TA_RPROC_CMD_LOAD_FW) and the starting of the remote
>> + * processor (TA_RPROC_CMD_START) or after stopping the remote processor
>> + * to release associated resources (TA_RPROC_CMD_STOP).
>> + *
>> + * [in]  params[0].value.a: remote processor identifier
>> + */
>> +#define TA_RPROC_CMD_RELEASE_FW		6
>> +
>> +struct rproc_tee_context {
>> +	struct list_head	rproc_list;
>> +	struct tee_context	*tee_ctx;
>> +	struct device		*dev;
>> +};
>> +
>> +/**
>> + * struct rproc_tee - TEE remoteproc structure
>> + * @node:       Reference in list
>> + * @rproc:      Remoteproc reference
>> + * @rproc_id:   remote processor identifier
>> + * @session_id: TEE session identifier
>> + */
>> +struct rproc_tee {
>> +	struct list_head node;
>> +	struct rproc *rproc;
>> +	u32 rproc_id;
>> +	u32 session_id;
>> +};
>> +
>> +static struct rproc_tee_context rproc_tee_ctx;
>> +static DEFINE_MUTEX(ctx_lock); /* Protects concurrent manipulations of the rproc_tee_ctx*/
>> +
>> +static struct rproc_tee *rproc_to_trproc(struct rproc *rproc)
>> +{
>> +	struct rproc_tee *trproc;
>> +
>> +	list_for_each_entry(trproc, &rproc_tee_ctx.rproc_list, node)
>> +		if (trproc->rproc == rproc)
>> +			return trproc;
>> +	return NULL;
>> +}
>> +
>> +static void rproc_tee_prepare_args(struct rproc_tee *trproc, int cmd,
>> +				   struct tee_ioctl_invoke_arg *arg,
>> +				   struct tee_param *param,
>> +				   unsigned int num_params)
>> +{
>> +	memset(arg, 0, sizeof(*arg));
>> +	memset(param, 0, MAX_TEE_PARAM_ARRAY_MEMBER * sizeof(*param));
>> +
>> +	arg->func = cmd;
>> +	arg->session = trproc->session_id;
>> +	arg->num_params = num_params + 1;
>> +
>> +	param[0] = (struct tee_param) {
>> +		.attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT,
>> +		.u.value.a = trproc->rproc_id,
>> +	};
>> +}
>> +
>> +/**
>> + * rproc_tee_release_fw() - Release the firmware for a TEE-based remote processor
>> + * @rproc: Pointer to the struct rproc representing the remote processor
>> + *
>> + * This function invokes the TA_RPROC_CMD_RELEASE_FW TEE client function to
>> + * release the firmware. It should only be called when the remoteproc state is
>> + * RPROC_OFFLINE or RPROC_DETACHED. The function requests the TEE remoteproc
>> + * application to release the firmware loaded by rproc_tee_load_fw().
>> + * The request is ignored if the rproc state is RPROC_DETACHED as the remote
>> + * processor is still running.
>> + */
>> +void rproc_tee_release_fw(struct rproc *rproc)
>> +{
>> +	struct tee_param param[MAX_TEE_PARAM_ARRAY_MEMBER];
>> +	struct rproc_tee *trproc;
>> +	struct tee_ioctl_invoke_arg arg;
>> +	int ret;
>> +
>> +	ret = mutex_lock_interruptible(&ctx_lock);
>> +	if (ret)
>> +		return;
>> +
>> +	if (!rproc_tee_ctx.dev)
>> +		goto out;
>> +
>> +	trproc = rproc_to_trproc(rproc);
>> +	if (!trproc)
>> +		goto out;
>> +
>> +	/*
>> +	 * If the remote processor state is RPROC_DETACHED, just ignore the
>> +	 * request, as the remote processor is still running.
>> +	 */
>> +	if (rproc->state == RPROC_DETACHED)
>> +		goto out;
>> +
>> +	if (rproc->state != RPROC_OFFLINE) {
>> +		dev_err(rproc_tee_ctx.dev, "unexpected rproc state: %d\n", rproc->state);
>> +		goto out;
>> +	}
>> +
>> +	rproc_tee_prepare_args(trproc, TA_RPROC_CMD_RELEASE_FW, &arg, param, 0);
>> +
>> +	ret = tee_client_invoke_func(rproc_tee_ctx.tee_ctx, &arg, param);
>> +	if (ret < 0 || arg.ret != 0) {
>> +		dev_err(rproc_tee_ctx.dev,
>> +			"TA_RPROC_CMD_RELEASE_FW invoke failed TEE err: %#x, ret:%d\n",
>> +			arg.ret, ret);
>> +	}
>> +
>> +out:
>> +	mutex_unlock(&ctx_lock);
>> +}
>> +EXPORT_SYMBOL_GPL(rproc_tee_release_fw);
>> +
>> +/**
>> + * rproc_tee_load_fw() - Load firmware from TEE application
>> + * @rproc: Pointer to the struct rproc representing the remote processor
>> + * @fw: Pointer to the firmware structure containing the firmware data and size
>> + *
>> + * This function invokes the TA_RPROC_CMD_LOAD_FW TEE client function to load
>> + * the firmware. It registers the fw->data as a shared memory region with the
>> + * TEE, and request the TEE to load the firmware. This function can be called
>> + * twice during the remote processor boot, a first by rproc_tee_parse_fw() to
>> + * parse the resource table , and a second time by rproc_tee_load_fw().
>> + * The TEE application should ignores the command if the firmware
>> + * is already loaded by rproc_tee_parse_fw().
>> + *
>> + * Return: 0 on success, or an error code on failure
>> + */
>> +int rproc_tee_load_fw(struct rproc *rproc, const struct firmware *fw)
>> +{
>> +	struct tee_param param[MAX_TEE_PARAM_ARRAY_MEMBER];
>> +	struct rproc_tee *trproc;
>> +	struct tee_ioctl_invoke_arg arg;
>> +	struct tee_shm *fw_shm;
>> +	int ret;
>> +
>> +	ret = mutex_lock_interruptible(&ctx_lock);
>> +	if (ret)
>> +		return ret;
>> +
>> +	if (!rproc_tee_ctx.dev) {
>> +		ret = -ENODEV;
>> +		goto out;
>> +	}
>> +
>> +	trproc = rproc_to_trproc(rproc);
>> +	if (!trproc) {
>> +		ret = -EINVAL;
>> +		goto out;
>> +	}
>> +
>> +	fw_shm = tee_shm_register_kernel_buf(rproc_tee_ctx.tee_ctx, (void *)fw->data, fw->size);
>> +	if (IS_ERR(fw_shm)) {
>> +		ret = PTR_ERR(fw_shm);
>> +		goto out;
>> +	}
>> +
>> +	rproc_tee_prepare_args(trproc, TA_RPROC_CMD_LOAD_FW, &arg, param, 1);
>> +
>> +	/* Provide the address of the firmware image */
>> +	param[1] = (struct tee_param) {
>> +		.attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT,
>> +		.u.memref = {
>> +			.shm = fw_shm,
>> +			.size = fw->size,
>> +			.shm_offs = 0,
>> +		},
>> +	};
>> +
>> +	ret = tee_client_invoke_func(rproc_tee_ctx.tee_ctx, &arg, param);
>> +	if (ret < 0 || arg.ret != 0) {
>> +		dev_err(rproc_tee_ctx.dev,
>> +			"TA_RPROC_CMD_LOAD_FW invoke failed TEE err: %#x, ret:%d\n",
>> +			arg.ret, ret);
>> +		if (!ret)
>> +			ret = -EIO;
>> +	}
>> +
>> +	tee_shm_free(fw_shm);
>> +
>> +out:
>> +	mutex_unlock(&ctx_lock);
>> +	return ret;
>> +}
>> +EXPORT_SYMBOL_GPL(rproc_tee_load_fw);
>> +
>> +static int rproc_tee_get_loaded_rsc_table(struct rproc *rproc, phys_addr_t *rsc_pa,
>> +					  size_t *table_sz)
>> +{
>> +	struct tee_param param[MAX_TEE_PARAM_ARRAY_MEMBER];
>> +	struct rproc_tee *trproc;
>> +	struct tee_ioctl_invoke_arg arg;
>> +	int ret;
>> +
>> +	ret = mutex_lock_interruptible(&ctx_lock);
>> +	if (ret)
>> +		return ret;
>> +
>> +	if (!rproc_tee_ctx.dev) {
>> +		ret = -ENODEV;
>> +		goto out;
>> +	}
>> +
>> +	trproc = rproc_to_trproc(rproc);
>> +	if (!trproc) {
>> +		ret = -EINVAL;
>> +		goto out;
>> +	}
>> +
>> +	rproc_tee_prepare_args(trproc, TA_RPROC_CMD_GET_RSC_TABLE, &arg, param, 2);
>> +
>> +	param[1].attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT;
>> +	param[2].attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT;
>> +
>> +	ret = tee_client_invoke_func(rproc_tee_ctx.tee_ctx, &arg, param);
>> +	if (ret < 0 || arg.ret != 0) {
>> +		dev_err(rproc_tee_ctx.dev,
>> +			"TA_RPROC_CMD_GET_RSC_TABLE invoke failed TEE err: %#x, ret:%d\n",
>> +			arg.ret, ret);
>> +		ret = -EIO;
>> +		goto out;
>> +	}
>> +
>> +	*table_sz = param[2].u.value.a;
>> +	if (sizeof(phys_addr_t) == sizeof(u64))
>> +		*table_sz |= param[2].u.value.b << 32;
>> +
>> +	if (*table_sz) {
>> +		*rsc_pa = param[1].u.value.a;
>> +		if (sizeof(phys_addr_t) == sizeof(u64))
>> +			*rsc_pa |= param[1].u.value.b << 32;
>> +	} else {
>> +		*rsc_pa = 0;
>> +	}
>> +
>> +out:
>> +	mutex_unlock(&ctx_lock);
>> +	return ret;
>> +}
>> +
>> +/**
>> + * rproc_tee_parse_fw() - Get the resource table from TEE application
>> + * @rproc: Pointer to the struct rproc representing the remote processor
>> + * @fw: Pointer to the firmware structure containing the firmware data and size
>> + *
>> + * This function retrieves the loaded resource table and creates a cached_table
>> + * copy. Since the firmware image is signed and potentially encrypted, the
>> + * firmware must be loaded first to access the loaded resource table.
>> + *
>> + * Return: 0 on success, or an error code on failure
>> + */
>> +int rproc_tee_parse_fw(struct rproc *rproc, const struct firmware *fw)
>> +{
>> +	phys_addr_t rsc_table;
>> +	void *rsc_va;
>> +	size_t table_sz;
>> +	int ret;
>> +
>> +	if (!rproc)
>> +		return -EINVAL;
>> +
>> +	/* We need first to Load the firmware, to be able to get the resource table. */
>> +	ret = rproc_tee_load_fw(rproc, fw);
>> +	if (ret)
>> +		return ret;
>> +
>> +	ret = rproc_tee_get_loaded_rsc_table(rproc, &rsc_table, &table_sz);
>> +	if (ret)
>> +		goto release_fw;
>> +
>> +	/*
>> +	 * We assume here that the memory mapping is the same between the TEE
>> +	 * and Linux kernel contexts. Else a new TEE remoteproc service could be
>> +	 * needed to get a copy of the resource table.
>> +	 */
>> +	rsc_va = memremap(rsc_table, table_sz, MEMREMAP_WC);
>> +	if (!rsc_va) {
>> +		dev_err(rproc_tee_ctx.dev, "Unable to map memory region: %pa+%zx\n",
>> +			&rsc_table, table_sz);
>> +		ret = -ENOMEM;
>> +		goto release_fw;
>> +	}
>> +
>> +	/*
>> +	 * Create a copy of the resource table to have the same behavior as the
>> +	 * ELF loader. This cached table will be used by the remoteproc core
>> +	 * after the remoteproc stops to free resources and for crash recovery
>> +	 * to reapply the settings.
>> +	 * The cached table will be freed by the remoteproc core.
>> +	 */
>> +	rproc->cached_table = kmemdup(rsc_va, table_sz, GFP_KERNEL);
>> +	memunmap(rsc_va);
>> +
>> +	if (!rproc->cached_table) {
>> +		ret = -ENOMEM;
>> +		goto release_fw;
>> +	}
>> +
>> +	rproc->table_ptr = rproc->cached_table;
>> +	rproc->table_sz = table_sz;
>> +
>> +	return 0;
>> +
>> +release_fw:
>> +	rproc_tee_release_fw(rproc);
>> +	return ret;
>> +}
>> +EXPORT_SYMBOL_GPL(rproc_tee_parse_fw);
>> +
>> +/**
>> + * rproc_tee_find_loaded_rsc_table() - Find the loaded resource table loaded by
>> + *				       the TEE application
>> + * @rproc: Pointer to the struct rproc representing the remote processor
>> + * @fw: Pointer to the firmware structure containing the firmware data and size
>> + *
>> + * This function retrieves the physical address and size of the resource table
>> + * loaded by the TEE application.
>> + *
>> + * Return: pointer to the resource table if found, or NULL if not found or size
>> + * is 0
>> + */
>> +struct resource_table *rproc_tee_find_loaded_rsc_table(struct rproc *rproc,
>> +						       const struct firmware *fw)
>> +{
>> +	phys_addr_t rsc_table;
>> +	size_t table_sz;
>> +	int ret;
>> +
>> +	ret = rproc_tee_get_loaded_rsc_table(rproc, &rsc_table, &table_sz);
>> +	if (ret)
>> +		return NULL;
>> +
>> +	rproc->table_sz = table_sz;
>> +	if (!table_sz)
>> +		return NULL;
>> +
>> +	/*
>> +	 * At this step the memory area that contains the resource table should
>> +	 * have been registered by the remote proc platform driver and allocated
>> +	 * by rproc_alloc_registered_carveouts().
>> +	 */
>> +	return rproc_pa_to_va(rproc, rsc_table, table_sz, NULL);
>> +}
>> +EXPORT_SYMBOL_GPL(rproc_tee_find_loaded_rsc_table);
>> +
>> +/**
>> + * rproc_tee_start() - Request the TEE application to start the remote processor
>> + * @rproc: Pointer to the struct rproc representing the remote processor
>> + *
>> + * This function invokes the TA_RPROC_CMD_START command to start the remote
>> + * processor.
>> + *
>> + * Return: Returns 0 on success, -EINVAL or -EIO on failure
>> + */
>> +int rproc_tee_start(struct rproc *rproc)
>> +{
>> +	struct tee_param param[MAX_TEE_PARAM_ARRAY_MEMBER];
>> +	struct rproc_tee *trproc;
>> +	struct tee_ioctl_invoke_arg arg;
>> +	int ret;
>> +
>> +	ret = mutex_lock_interruptible(&ctx_lock);
>> +	if (ret)
>> +		return ret;
>> +
>> +	if (!rproc_tee_ctx.dev) {
>> +		ret = -ENODEV;
>> +		goto out;
>> +	}
>> +
>> +	trproc = rproc_to_trproc(rproc);
>> +	if (!trproc) {
>> +		ret = -EINVAL;
>> +		goto out;
>> +	}
>> +
>> +	rproc_tee_prepare_args(trproc, TA_RPROC_CMD_START, &arg, param, 0);
>> +
>> +	ret = tee_client_invoke_func(rproc_tee_ctx.tee_ctx, &arg, param);
>> +	if (ret < 0 || arg.ret != 0) {
>> +		dev_err(rproc_tee_ctx.dev,
>> +			"TA_RPROC_CMD_START invoke failed TEE err: %#x, ret:%d\n", arg.ret, ret);
>> +		if (!ret)
>> +			ret = -EIO;
>> +	}
>> +
>> +out:
>> +	mutex_unlock(&ctx_lock);
>> +	return ret;
>> +}
>> +EXPORT_SYMBOL_GPL(rproc_tee_start);
>> +
>> +/**
>> + * rproc_tee_stop() - Request the TEE application to start the remote processor
>> + * @rproc: Pointer to the struct rproc representing the remote processor
>> + *
>> + * This function invokes the TA_RPROC_CMD_STOP command to stop the remote
>> + * processor.
>> + *
>> + * Return: Returns 0 on success, -EINVAL or -EIO on failure
>> + */
>> +int rproc_tee_stop(struct rproc *rproc)
>> +{
>> +	struct tee_param param[MAX_TEE_PARAM_ARRAY_MEMBER];
>> +	struct rproc_tee *trproc;
>> +	struct tee_ioctl_invoke_arg arg;
>> +	int ret;
>> +
>> +	ret = mutex_lock_interruptible(&ctx_lock);
>> +	if (ret)
>> +		return ret;
>> +
>> +	if (!rproc_tee_ctx.dev) {
>> +		ret = -ENODEV;
>> +		goto out;
>> +	}
>> +
>> +	trproc = rproc_to_trproc(rproc);
>> +	if (!trproc) {
>> +		ret = -EINVAL;
>> +		goto out;
>> +	}
>> +
>> +	rproc_tee_prepare_args(trproc, TA_RPROC_CMD_STOP, &arg, param, 0);
>> +
>> +	ret = tee_client_invoke_func(rproc_tee_ctx.tee_ctx, &arg, param);
>> +	if (ret < 0 || arg.ret != 0) {
>> +		dev_err(rproc_tee_ctx.dev,
>> +			"TA_RPROC_CMD_STOP invoke failed TEE err: %#x, ret:%d\n", arg.ret, ret);
>> +		if (!ret)
>> +			ret = -EIO;
>> +	}
>> +
>> +out:
>> +	mutex_unlock(&ctx_lock);
>> +	return ret;
>> +}
>> +EXPORT_SYMBOL_GPL(rproc_tee_stop);
>> +
>> +static const struct rproc_ops rproc_tee_default_ops = {
>> +	.start		= rproc_tee_start,
>> +	.stop		= rproc_tee_stop,
>> +	.load		= rproc_tee_load_fw,
>> +	.parse_fw	= rproc_tee_parse_fw,
>> +	.find_loaded_rsc_table = rproc_tee_find_loaded_rsc_table,
>> +	.release_fw	= rproc_tee_release_fw,
>> +};
>> +
>> +static const struct tee_client_device_id rproc_tee_id_table[] = {
>> +	{UUID_INIT(0x80a4c275, 0x0a47, 0x4905, 0x82, 0x85, 0x14, 0x86, 0xa9, 0x77, 0x1a, 0x08)},
>> +	{ /* sentinel */ }
>> +};
>> +
>> +/**
>> + * rproc_tee_register() - Register a remote processor controlled by the TEE application.
>> + * @dev: Pointer to client rproc device
>> + * @rproc: Pointer to the struct rproc representing the remote processor
>> + * @rproc_id: ID of the remote processor
>> + * @auto_boot: flag to indicate if remote processor should be auto-started
>> + *
>> + * This function registers a remote processor that will be managed by a TEE
>> + * application, by opening a session with the TEE client.
>> + *
>> + * Return: Returns 0 on success, or an error code on failure
>> + */
>> +int rproc_tee_register(struct device *dev, struct rproc **rproc,
>> +		       unsigned int rproc_id, bool auto_boot)
>> +{
>> +	struct tee_param param[MAX_TEE_PARAM_ARRAY_MEMBER];
>> +	struct tee_ioctl_open_session_arg sess_arg;
>> +	struct device_node *np = dev->of_node;
>> +	struct tee_client_device *tee_device;
>> +	struct rproc *new_rproc;
>> +	struct rproc_tee *trproc;
>> +	const char *fw_name;
>> +	int ret;
>> +
>> +	ret = mutex_lock_interruptible(&ctx_lock);
>> +	if (ret)
>> +		return ret;
>> +
>> +	if (!rproc_tee_ctx.dev) {
>> +		ret = -ENODEV;
>> +		goto out;
>> +	}
>> +
>> +	trproc = kzalloc(sizeof(*trproc), GFP_KERNEL);
>> +	if (!trproc) {
>> +		ret = -ENOMEM;
>> +		goto out;
>> +	}
>> +
>> +	/* Look for an optional firmware name */
>> +	ret = rproc_of_parse_firmware(dev, 0, &fw_name);
>> +	if (ret < 0 && ret != -EINVAL)
>> +		goto free_tproc;
>> +
>> +	new_rproc = rproc_alloc(dev, np->name, &rproc_tee_default_ops,
>> +				fw_name, sizeof(*trproc));
>> +	if (!new_rproc) {
>> +		ret = -ENOMEM;
>> +		goto free_tproc;
>> +	}
>> +
>> +	tee_device = to_tee_client_device(rproc_tee_ctx.dev);
>> +	memset(&sess_arg, 0, sizeof(sess_arg));
>> +
>> +	memcpy(sess_arg.uuid, tee_device->id.uuid.b, TEE_IOCTL_UUID_LEN);
>> +
>> +	sess_arg.clnt_login = TEE_IOCTL_LOGIN_REE_KERNEL;
>> +	sess_arg.num_params = 1;
>> +
>> +	param[0] = (struct tee_param) {
>> +		.attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT,
>> +		.u.value.a = rproc_id,
>> +	};
>> +
>> +	ret = tee_client_open_session(rproc_tee_ctx.tee_ctx, &sess_arg, param);
>> +	if (ret < 0 || sess_arg.ret != 0) {
>> +		dev_err(dev, "tee_client_open_session failed, err: %#x\n", sess_arg.ret);
>> +		ret = -EINVAL;
>> +		goto free_rproc;
>> +	}
>> +
>> +	trproc->rproc_id = rproc_id;
>> +	trproc->session_id = sess_arg.session;
>> +	new_rproc->auto_boot = auto_boot;
>> +
>> +	ret = rproc_add(new_rproc);
>> +	if (ret)
>> +		goto close_tee;
>> +
>> +	trproc->rproc = new_rproc;
>> +	*rproc = new_rproc;
>> +
>> +	list_add_tail(&trproc->node, &rproc_tee_ctx.rproc_list);
>> +
>> +	mutex_unlock(&ctx_lock);
>> +
>> +	return 0;
>> +
>> +close_tee:
>> +	if (tee_client_close_session(rproc_tee_ctx.tee_ctx, trproc->session_id))
>> +		dev_err(rproc_tee_ctx.dev, "tee_client_close_session failed\n");
>> +free_rproc:
>> +	rproc_free(new_rproc);
>> +free_tproc:
>> +	kfree(trproc);
>> +out:
>> +	mutex_unlock(&ctx_lock);
>> +	return ret;
>> +}
>> +EXPORT_SYMBOL_GPL(rproc_tee_register);
>> +
>> +/**
>> + * rproc_tee_unregister - Unregister a remote processor controlled by the TEE
>> + *                        application.
>> + * @dev: Pointer to client rproc device
>> + * @rproc: Pointer to the struct rproc representing the remote processor
>> + *
>> + * This function unregisters a remote processor previously registered by the
>> + * rproc_tee_register() function.
>> + *
>> + * Return: Returns 0 on success, or an error code on failure
>> + */
>> +int rproc_tee_unregister(struct device *dev, struct rproc *rproc)
>> +{
>> +	struct rproc_tee *trproc;
>> +	int ret;
>> +
>> +	if (!rproc_tee_ctx.dev) {
>> +		ret = -ENODEV;
>> +		return ret;
>> +	}
>> +
>> +	trproc = rproc_to_trproc(rproc);
>> +	if (!trproc) {
>> +		ret = -EINVAL;
>> +		return ret;
>> +	}
>> +
>> +	rproc_del(rproc);
>> +	rproc_free(rproc);
>> +
>> +	ret = mutex_lock_interruptible(&ctx_lock);
>> +	if (ret)
>> +		return ret;
>> +
>> +	ret = tee_client_close_session(rproc_tee_ctx.tee_ctx, trproc->session_id);
>> +	if (ret < 0)
>> +		dev_err(rproc_tee_ctx.dev, "tee_client_close_session failed, err: %#x\n", ret);
>> +	list_del(&trproc->node);
>> +	kfree(trproc);
>> +	mutex_unlock(&ctx_lock);
>> +
>> +	return ret;
>> +}
>> +EXPORT_SYMBOL_GPL(rproc_tee_unregister);
>> +
>> +static int rproc_tee_ctx_match(struct tee_ioctl_version_data *ver, const void *data)
>> +{
>> +	/* Today we support only the OP-TEE, could be extend to other tees */
>> +	return (ver->impl_id == TEE_IMPL_ID_OPTEE);
>> +}
>> +
>> +static const struct of_device_id remoteproc_tee_of_match[] = {
>> +	{ .compatible = "rproc-service-80a4c275-0a47-4905-8285-1486a9771a08" },
>> +	{ /* sentinel */ }
>> +};
>> +MODULE_DEVICE_TABLE(of, remoteproc_tee_of_match);
> 
> You don't need to define this redundant table but instead...
> 
>> +
>> +static int rproc_tee_probe(struct device *dev)
>> +{
>> +	struct tee_context *tee_ctx;
>> +	struct device_node *np;
>> +	int ret;
>> +
>> +	pr_err("%s %d", __func__, __LINE__);
>> +	np = of_find_compatible_node(NULL, NULL,
>> +				     remoteproc_tee_of_match[0].compatible);
> 
> ...you can get the UUID from device being passed here. With that you
> should be able to fetch device specific DT properties.

Yes that makes sense, if the compatible in DT is the UUID

Thanks,

Arnaud

> 
> -Sumit
> 
>> +	if (!np) {
>> +		dev_err(dev, "Device node not found\n");
>> +		return -ENODEV;
>> +	}
>> +
>> +	/* Open context with TEE driver */
>> +	tee_ctx = tee_client_open_context(NULL, rproc_tee_ctx_match, NULL, NULL);
>> +	if (IS_ERR(tee_ctx)) {
>> +		ret = PTR_ERR(tee_ctx);
>> +		goto put_node;
>> +	}
>> +
>> +	ret = mutex_lock_interruptible(&ctx_lock);
>> +	if (ret)
>> +		goto close_ctx;
>> +
>> +	rproc_tee_ctx.dev = dev;
>> +	rproc_tee_ctx.tee_ctx = tee_ctx;
>> +	INIT_LIST_HEAD(&rproc_tee_ctx.rproc_list);
>> +
>> +	mutex_unlock(&ctx_lock);
>> +
>> +	ret = device_add_of_node(dev, np);
>> +	if (ret)
>> +		goto clean_ctx;
>> +
>> +	ret = of_platform_populate(np, NULL, NULL, dev);
>> +	if (ret) {
>> +		dev_err(dev, "cannot populate node (%d)\n", ret);
>> +		goto clean_ctx;
>> +	}
>> +
>> +	return 0;
>> +
>> +clean_ctx:
>> +	mutex_lock(&ctx_lock);
>> +	rproc_tee_ctx.dev = NULL;
>> +	rproc_tee_ctx.tee_ctx = NULL;
>> +	mutex_unlock(&ctx_lock);
>> +
>> +close_ctx:
>> +	tee_client_close_context(tee_ctx);
>> +
>> +put_node:
>> +	of_node_put(np);
>> +	return ret;
>> +}
>> +
>> +static int rproc_tee_remove(struct device *dev)
>> +{
>> +	of_platform_depopulate(dev);
>> +
>> +	device_remove_of_node(dev);
>> +
>> +	mutex_lock(&ctx_lock);
>> +	tee_client_close_context(rproc_tee_ctx.tee_ctx);
>> +	rproc_tee_ctx.dev = NULL;
>> +	rproc_tee_ctx.tee_ctx = NULL;
>> +	mutex_unlock(&ctx_lock);
>> +
>> +	return 0;
>> +}
>> +
>> +MODULE_DEVICE_TABLE(tee, rproc_tee_id_table);
>> +
>> +static struct tee_client_driver rproc_tee_fw_driver = {
>> +	.id_table	= rproc_tee_id_table,
>> +	.driver		= {
>> +		.name		= KBUILD_MODNAME,
>> +		.bus		= &tee_bus_type,
>> +		.probe		= rproc_tee_probe,
>> +		.remove		= rproc_tee_remove,
>> +	},
>> +};
>> +
>> +static int __init rproc_tee_fw_mod_init(void)
>> +{
>> +	return driver_register(&rproc_tee_fw_driver.driver);
>> +}
>> +
>> +static void __exit rproc_tee_fw_mod_exit(void)
>> +{
>> +	driver_unregister(&rproc_tee_fw_driver.driver);
>> +}
>> +
>> +module_init(rproc_tee_fw_mod_init);
>> +module_exit(rproc_tee_fw_mod_exit);
>> +
>> +MODULE_DESCRIPTION("remote processor TEE module");
>> +MODULE_LICENSE("GPL");
>> diff --git a/include/linux/remoteproc_tee.h b/include/linux/remoteproc_tee.h
>> new file mode 100644
>> index 000000000000..33150cff7a5a
>> --- /dev/null
>> +++ b/include/linux/remoteproc_tee.h
>> @@ -0,0 +1,89 @@
>> +/* SPDX-License-Identifier: GPL-2.0-or-later */
>> +/*
>> + * Copyright(c) 2025 STMicroelectronics
>> + */
>> +
>> +#ifndef REMOTEPROC_TEE_H
>> +#define REMOTEPROC_TEE_H
>> +
>> +#include <linux/tee_drv.h>
>> +#include <linux/firmware.h>
>> +#include <linux/remoteproc.h>
>> +
>> +#if IS_ENABLED(CONFIG_REMOTEPROC_TEE)
>> +
>> +int rproc_tee_register(struct device *dev, struct rproc **rproc,
>> +		       unsigned int rproc_id, bool auto_boot);
>> +int rproc_tee_unregister(struct device *dev, struct rproc *rproc);
>> +int rproc_tee_parse_fw(struct rproc *rproc, const struct firmware *fw);
>> +int rproc_tee_load_fw(struct rproc *rproc, const struct firmware *fw);
>> +void rproc_tee_release_fw(struct rproc *rproc);
>> +struct resource_table *rproc_tee_find_loaded_rsc_table(struct rproc *rproc,
>> +						       const struct firmware *fw);
>> +int rproc_tee_start(struct rproc *rproc);
>> +int rproc_tee_stop(struct rproc *rproc);
>> +int rproc_tee_pa_to_da(struct rproc *rproc, phys_addr_t pa, size_t size, u64 *da);
>> +#else
>> +
>> +static inline int rproc_tee_register(struct device *dev, struct rproc **rproc,
>> +				     unsigned int rproc_id, bool auto_boot)
>> +{
>> +	return -ENODEV;
>> +}
>> +
>> +static inline int rproc_tee_parse_fw(struct rproc *rproc, const struct firmware *fw)
>> +{
>> +	/* This shouldn't be possible */
>> +	WARN_ON(1);
>> +
>> +	return 0;
>> +}
>> +
>> +static inline int rproc_tee_unregister(struct device *dev, struct rproc *rproc)
>> +{
>> +	/* This shouldn't be possible */
>> +	WARN_ON(1);
>> +
>> +	return 0;
>> +}
>> +
>> +static inline int rproc_tee_load_fw(struct rproc *rproc, const struct firmware *fw)
>> +{
>> +	/* This shouldn't be possible */
>> +	WARN_ON(1);
>> +
>> +	return 0;
>> +}
>> +
>> +static inline int rproc_tee_start(struct rproc *rproc)
>> +{
>> +	/* This shouldn't be possible */
>> +	WARN_ON(1);
>> +
>> +	return 0;
>> +}
>> +
>> +static inline int rproc_tee_stop(struct rproc *rproc)
>> +{
>> +	/* This shouldn't be possible */
>> +	WARN_ON(1);
>> +
>> +	return 0;
>> +}
>> +
>> +static inline void rproc_tee_release_fw(struct rproc *rproc)
>> +{
>> +	/* This shouldn't be possible */
>> +	WARN_ON(1);
>> +}
>> +
>> +static inline struct resource_table *
>> +rproc_tee_find_loaded_rsc_table(struct rproc *rproc, const struct firmware *fw)
>> +{
>> +	/* This shouldn't be possible */
>> +	WARN_ON(1);
>> +
>> +	return NULL;
>> +}
>> +#endif /* CONFIG_REMOTEPROC_TEE */
>> +#endif /* REMOTEPROC_TEE_H */
>> -- 
>> 2.43.0
>>